Huijuan, Z., Fan, J., Han, J. ...
· biochemistry
· Fudan University
· biorxiv
Immunoglobulin G (IgG) N-glycans have been identified as associated with aging; however, previous studies predominantly quantified changes based on the relative percentages of each glycan within the total glycan pool, neglecting the absolute concentration changes of individual gl...
Immunoglobulin G (IgG) N-glycans have been identified as associated with aging; however, previous studies predominantly quantified changes based on the relative percentages of each glycan within the total glycan pool, neglecting the absolute concentration changes of individual glycans. Additionally, relative quantification can limit practical applications, as these often require absolute concentration measurements for consistent and interpretable biomarker values. In this study, we introduce a novel strategy for discovering aging-associated IgG glycans and establishing a prediction model based on their absolute concentration alteration. We employed a glycome quantification technology to identify the alteration in IgG glycan amount in natural aging and anti-aging (caloric restriction) models, discovering aging-related glycans. The glycomics analysis revealed key features: downregulation of bisected glycan GP3 (F(6)A2B) and upregulation of digalactosylated glycan GP8 (F(6)A2G2). These glycan changes showed significant fold changes from an early stage. Using external standards of these two glycans, we subsequently measured the absolute concentrations of them, allowing us to establish a predictive model, abGlycoAge, for biological aging. The abGlycoAge index suggested a younger state under caloric restriction, with an average age reduction of 3.9-14 weeks. Additionally, we performed RNA sequencing on splenic B cells of mice, suggesting Derl3, Smarcb1, Ankrd55, Tbkbp1 and Slc38a10 could contribute to the alteration of GP3 and GP8 in aging. This analysis enhances our understanding of glycan alterations, accounts for individual variability, and aids in designing effective anti-aging strategies. These findings highlight the crucial roles of the GP3 and GP8 as potential biomarkers for aging and health.
Longevity Relevance Analysis
(4)
The paper addresses the quantification of aging-associated glycans in IgG, which is directly related to biological aging and has implications for understanding the mechanisms of aging. By focusing on absolute concentrations rather than relative percentages, the study provides a more robust framework for identifying biomarkers of aging, which could aid in developing anti-aging strategies. However, while the findings are solid and contribute to the field, they do not represent a major breakthrough or transformative advancement, hence the moderate impact score.
Goran Papenberg, Nina Karalija, Alireza Salami ...
· Cerebral cortex (New York, N.Y. : 1991)
· Aging Research Center, Karolinska Institutet and Stockholm University, Tomtebodavägen 18 A, SE-171 65 Solna, Sweden.
· pubmed
Although age differences in the dopamine system have been suggested to contribute to age-related cognitive decline based on cross-sectional data, recent large-scale cross-sectional studies reported only weak evidence for a correlation among aging, dopamine receptor availability, ...
Although age differences in the dopamine system have been suggested to contribute to age-related cognitive decline based on cross-sectional data, recent large-scale cross-sectional studies reported only weak evidence for a correlation among aging, dopamine receptor availability, and cognition. Regardless, longitudinal data remain essential to make robust statements about dopamine losses as a basis for cognitive aging. We present correlations between changes in D2/3 dopamine receptor availability and changes in working memory measured over 5 yr in healthy, older adults (n = 128, ages 64 to 68 yr at baseline). Greater decline in D2/3 dopamine receptor availability in working memory-relevant regions (caudate, middle frontal cortex, hippocampus) was related to greater decline in working memory performance in individuals who exhibited working memory reductions across time (n = 43; caudate: rs = 0.494; middle frontal cortex: rs = 0.506; hippocampus; rs = 0.423), but not in individuals who maintained performance (n = 41; caudate: rs = 0.052; middle frontal cortex: rs = 0.198; hippocampus; rs = 0.076). The dopamine-working memory link in decliners was not observed in the orbitofrontal cortex, which does not belong to the core working memory network. Our longitudinal analyses support the notion that aging-related changes in the dopamine system contribute to working memory decline in aging.
Longevity Relevance Analysis
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The paper investigates the relationship between dopamine D2/3 receptor availability and working memory decline in aging, contributing to the understanding of cognitive aging mechanisms. While it provides valuable longitudinal data, its findings are somewhat incremental and primarily focus on correlational aspects rather than addressing root causes of aging or proposing interventions for lifespan extension. Thus, it has solid research value but limited broader impact on the field of longevity.
Marques, E., Burr, S. P., Casey, A. M. ...
· immunology
· University of Cambridge
· biorxiv
Impaired mitochondrial bioenergetics in macrophages can drive hyperinflammatory cytokine responses, but whether this may also be caused by inherited mtDNA mutations is unknown. Here, we address this question using a multi-omic approach that integrates super-resolution imaging and...
Impaired mitochondrial bioenergetics in macrophages can drive hyperinflammatory cytokine responses, but whether this may also be caused by inherited mtDNA mutations is unknown. Here, we address this question using a multi-omic approach that integrates super-resolution imaging and metabolic analyses to profile macrophages from a mouse model of mitochondrial disease arising from a heteroplasmic mutation (m.5019A>G) in the mitochondrial tRNA for alanine. These m.5019A>G macrophages exhibit defects in respiratory chain complexes and oxidative phosphorylation (OxPhos) due to decreased intra-mitochondrial translation. To adapt to this metabolic stress, mitochondrial fusion, reductive glutamine metabolism, and aerobic glycolysis are all increased. Upon inflammatory activation, type I interferon (IFN-I) release is enhanced, while the production of pro-inflammatory cytokines and oxylipins are restrained in m.5019A>G macrophages. Finally, an in vivo endotoxemia model using m.5019A>G mice reveal elevated IFN-I levels and sickness behaviour. In conclusion, our study identifies an unexpected imbalance in innate immune signalling in response to a pathogenic mtDNA mutation, with important implications for the progression of pathology in patients with mtDNA diseases.
Longevity Relevance Analysis
(4)
The paper investigates the effects of inherited mitochondrial DNA mutations on inflammatory responses in macrophages, which can be linked to aging and age-related diseases due to the role of mitochondrial dysfunction in the aging process. However, while it presents solid research and contributes to understanding the mechanisms of inflammation related to mitochondrial mutations, it does not directly address root causes of aging or lifespan extension. Thus, its impact is solid but limited.
Boquet-Pujadas, A., Anagnostakis, F., Duggan, M. ...
· health informatics
· Columbia University
· medrxiv
Multiorgan research investigates interconnections among multiple human organ systems, enhancing our understanding of human aging and disease mechanisms. Here, we used multiorgan imaging (N=105,433), individual and summary level genetics, and proteomics (N=53,940) from the UK Biob...
Multiorgan research investigates interconnections among multiple human organ systems, enhancing our understanding of human aging and disease mechanisms. Here, we used multiorgan imaging (N=105,433), individual and summary level genetics, and proteomics (N=53,940) from the UK Biobank, Baltimore Longitudinal Study of Aging, FinnGen, and Psychiatric Genomics Consortium to delineate a brain-heart-eye axis via 2003 brain patterns of structural covariance (PSC), 82 heart imaging-derived phenotypes (IDP) and 84 eye IDPs. Cross-organ phenotypic associations highlight the central autonomic network between the brain and heart and the central visual pathway between the brain and eye. Proteome wide associations of the PSCs and IDPs show both within organ specificity and cross-organ interconnections, verified by the RNA and protein expression profiles of the 2923 plasma proteins. Pleiotropic effects of common genetic variants are observed across multiple organs, and key genetic parameters, such as SNP-based heritability, polygenicity, and selection signatures, are comparatively evaluated among the three organs. A gene-drug-disease network shows the potential of drug repurposing for cross-organ diseases. Colocalization and causal analyses reveal cross-organ causal relationships between PSC/IDP and chronic diseases, such as Alzheimer's disease, heart failure, and glaucoma. Finally, integrating multi-organ/omics features improves prediction for systemic disease categories and cognition compared to single-organ/omics features. This study depicts a detailed brain-heart-eye axis and highlights future avenues for modeling human aging and disease across multiple scales. All results are publicly available at https://labs-laboratory.com/medicine/.
Longevity Relevance Analysis
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The paper explores the interconnections among multiple organ systems and their implications for chronic diseases, which is relevant to understanding aging mechanisms. However, it primarily focuses on associations and potential drug repurposing rather than addressing the root causes of aging or lifespan extension directly. The findings contribute solid insights into the relationships between organs but do not present a major breakthrough or transformative implications for the field of longevity research.
Gang Xu, Youhua Wang
· Tendons
· Department of Orthopaedics, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China; Department of Orthopaedics, The Eighth People's Hospital of Tongzhou, Nantong, Jiangsu, China.
· pubmed
Age-related diseases are often linked to chronic inflammation. Senescent cells secrete inflammatory cytokines, chemokines and matrix metalloproteinases, collectively referred to as the senescence-associated secretory phenotype (SASP). The current study discovered that aging leads...
Age-related diseases are often linked to chronic inflammation. Senescent cells secrete inflammatory cytokines, chemokines and matrix metalloproteinases, collectively referred to as the senescence-associated secretory phenotype (SASP). The current study discovered that aging leads to the accumulation of senescent tendon stem/progenitor cells (TSPCs) in tendon tissue, resulting in the development of a SASP. Conditioned medium from aged TSPCs induced cellular inflammation in young TSPCs. In addition, we found that Canopy homolog 2 (CNPY2) expression is reduced during tendon aging. CNPY2 deficiency causes TSPCs senescence and SASP. Our findings showed that the NF-κB signaling pathway is activated in CNPY2 knockdown TSPCs, pharmacological inhibition of NF-κB signaling pathway with BMS-345541 attenuated SASP of senescent TSPCs, which indicated that CNPY2 regulates TSPCs SASP might through NF-κB signaling pathway. Our findings suggested that CNPY2 plays an important role in TSPCs senescence and SASP, CNPY2 could be a promising target for age-related tendon disorders.
Longevity Relevance Analysis
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CNPY2 deficiency leads to senescence and the senescence-associated secretory phenotype in tendon stem/progenitor cells, suggesting a potential target for age-related tendon disorders. The study addresses the mechanisms of cellular senescence and inflammation, which are central to the aging process and age-related diseases.
Chee Hoe Kong, Chris Steffi, Yanli Cai ...
· Strontium
· Department of Orthopaedic Surgery, National University of Singapore, NUHS Tower Block, Level 11, 1E Kent Ridge Road, Singapore 119228, Singapore. Electronic address: [email protected].
· pubmed
Osteoporosis, characterized by reduced bone mineral density and increased fracture risk, poses a significant health challenge, particularly for aging populations. Systemic treatments often lead to adverse side effects, emphasizing the need for localized solutions. This study intr...
Osteoporosis, characterized by reduced bone mineral density and increased fracture risk, poses a significant health challenge, particularly for aging populations. Systemic treatments often lead to adverse side effects, emphasizing the need for localized solutions. This study introduces a 3D-printed polycaprolactone (PCL) scaffold embedded with strontium-substituted mesoporous bioactive glass nanoparticles (Sr-MBGNPs) and icariin (ICN) for the targeted regeneration of osteoporotic bone. The scaffold was characterized using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), ion release studies, and cellular assays, which confirmed its dual functionality in both enhancing osteoblast proliferation and differentiation and inhibiting osteoclastogenesis. The optimized Sr-MBGNP concentration ensured sustained ion release, superior hydrophilicity, and bioactivity without compromising scaffold integrity. Additionally, e-jet printing provided high precision and uniform pore sizes conducive to cellular activity. This novel scaffold platform demonstrates a promising localized treatment strategy, reducing systemic side effects while improving fixation stability. The innovative integration of Sr-MBGNPs and ICN highlights its potential to revolutionize osteoporosis therapy by promoting bone regeneration and mitigating bone resorption.
Longevity Relevance Analysis
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The study claims that a 3D-printed polycaprolactone scaffold embedded with strontium-substituted mesoporous bioactive glass nanoparticles can enhance osteoblast proliferation and inhibit osteoclastogenesis for bone regeneration. This paper is relevant as it addresses osteoporosis, a significant age-related condition, by proposing a localized treatment strategy that could improve bone health and potentially mitigate the effects of aging on bone density.
Thomas Mortimer, Jacob G Smith, Pura Muñoz-Cánoves ...
· Nature reviews. Molecular cell biology
· Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Barcelona, Spain. [email protected].
· pubmed
Maintaining homeostasis is essential for continued health, and the progressive decay of homeostatic processes is a hallmark of ageing. Daily environmental rhythms threaten homeostasis, and circadian clocks have evolved to execute physiological processes in a manner that anticipat...
Maintaining homeostasis is essential for continued health, and the progressive decay of homeostatic processes is a hallmark of ageing. Daily environmental rhythms threaten homeostasis, and circadian clocks have evolved to execute physiological processes in a manner that anticipates, and thus mitigates, their effects on the organism. Clocks are active in almost all cell types; their rhythmicity and functional output are determined by a combination of tissue-intrinsic and systemic inputs. Numerous inputs for a specific tissue are produced by the activity of circadian clocks of other tissues or cell types, generating a form of crosstalk known as clock communication. In mammals, the central clock in the hypothalamus integrates signals from external light-dark cycles to align peripheral clocks elsewhere in the body. This regulation is complemented by a tissue-specific milieu of external, systemic and niche inputs that modulate and cooperate with the cellular circadian clock machinery of a tissue to tailor its functional output. These mechanisms of clock communication decay during ageing, and growing evidence suggests that this decline might drive ageing-related morbidities. Dietary, behavioural and pharmacological interventions may offer the possibility to overcome these changes and in turn improve healthspan.
Longevity Relevance Analysis
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The paper discusses the role of circadian clocks in maintaining homeostasis and how their dysfunction during aging may contribute to age-related morbidities. This focus on the mechanisms underlying aging processes and potential interventions aligns with longevity research. The findings could advance understanding of how circadian rhythms influence healthspan, making it a significant contribution to the field, though not groundbreaking enough for a higher impact score.
Breen, A. K., Thomas, S., Beckett, D. ...
· molecular biology
· Western University of Health Sciences
· biorxiv
Inhibition of the target of rapamycin (TOR/mTOR) protein kinase by the drug rapamycin extends lifespan and healthspan across diverse species. However, rapamycin has potential off-target and side effects that warrant the discovery of additional TOR inhibitors. TOR was initially di...
Inhibition of the target of rapamycin (TOR/mTOR) protein kinase by the drug rapamycin extends lifespan and healthspan across diverse species. However, rapamycin has potential off-target and side effects that warrant the discovery of additional TOR inhibitors. TOR was initially discovered in Saccharomyces cerevisiae (yeast) which contains two TOR paralogs, TOR1 and TOR2. Yeast lacking functional Tor1 are viable but are hypersensitive to growth inhibition by TORC1 inhibitors, which is a property of yeast that can be exploited to identify TOR inhibitors. Additionally, yeast lacking FK506-sensitive proline rotamase (FPR1) or containing a tor1-1 allele (a mutation in the Fpr1-rapamycin binding domain of Tor1) are robustly and selectively resistant to rapamycin and analogs that allosterically inhibit TOR activity via an FPR1-dependent mechanism. To facilitate the identification of TOR inhibitors, we generated a panel of yeast strains with mutations in TOR pathway genes combined with the removal of 12 additional genes involved in drug efflux. This creates a drug sensitive strain background that can sensitively and effectively identify TOR inhibitors. In a wildtype yeast strain background, 25 micomolar of Torin1 and 100 micomolar of GSK2126458 (omipalisib) are necessary to observe TOR1-dependent growth inhibition by these known TOR inhibitors. In contrast, 100 nM Torin1 and 500 nM GSK2126458 (omipalisib) are sufficient to identify TOR1-dependent growth inhibition in the drug sensitized background. This represents a 200-fold and 250-fold increase in detection sensitivity for Torin1 and GSK2126458, respectively. Additionally, for the TOR inhibitor AZD8055, the drug sensitive system resolves that the compound results in TOR1-dependent growth sensitivity at 100 micomolar, whereas no growth inhibition is observed in a wildtype yeast strain background. Our platform also identifies the caffeine analog aminophylline as a TOR1-dependent growth inhibitor via selective tor1 growth sensitivity. We also tested nebivolol, isoliquiritigenin, canagliflozin, withaferin A, ganoderic acid A, and taurine, and found no evidence for TOR inhibition using our yeast growth-based model. Our results demonstrate that this system is highly effective at identifying compounds that inhibit the TOR pathway. It offers a rapid, cost-efficient, and sensitive tool for drug discovery, with the potential to expedite the identification of new TOR inhibitors that could serve as geroprotective and/or anti-cancer agents.
Longevity Relevance Analysis
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The paper is relevant to longevity research as it focuses on the discovery of new TOR inhibitors, which could potentially extend lifespan and healthspan by targeting the mTOR pathway, a known regulator of aging. However, while the research presents a solid methodology for identifying these inhibitors, it does not provide groundbreaking findings or novel insights that significantly advance the field, thus earning a moderate impact score.
Cathrin E Hansen, Davide Vacondio, Lennart van der Molen ...
· Cell death & disease
· Amsterdam UMC location Vrije Universiteit Amsterdam, Department of Molecular Cell Biology and Immunology, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands. [email protected].
· pubmed
Aging of the brain vasculature plays a key role in the development of neurovascular and neurodegenerative diseases, thereby contributing to cognitive impairment. Among other factors, DNA damage strongly promotes cellular aging, however, the role of genomic instability in brain en...
Aging of the brain vasculature plays a key role in the development of neurovascular and neurodegenerative diseases, thereby contributing to cognitive impairment. Among other factors, DNA damage strongly promotes cellular aging, however, the role of genomic instability in brain endothelial cells (EC) and its potential effect on brain homeostasis is still largely unclear. We here investigated how endothelial aging impacts blood-brain barrier (BBB) function by using excision repair cross complementation group 1 (ERCC1)-deficient human brain ECs and an EC-specific Ercc1 knock out (EC-KO) mouse model. In vitro, ERCC1-deficient brain ECs displayed increased senescence-associated secretory phenotype expression, reduced BBB integrity, and higher sprouting capacities due to an underlying dysregulation of the Dll4-Notch pathway. In line, EC-KO mice showed more P21
Longevity Relevance Analysis
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The paper investigates the role of DNA repair deficiency in brain endothelial cells and its impact on blood-brain barrier dysfunction, which is a significant aspect of aging and neurodegenerative diseases. By focusing on the underlying mechanisms of endothelial aging and its effects on brain homeostasis, it addresses a root cause of age-related decline in cognitive function. However, while the findings are solid and contribute to understanding the aging process, they do not present a major breakthrough or transformative implications for longevity research, thus warranting a moderate impact score.
Anna Ungvari, Rafal Gulej, Roland Patai ...
· GeroScience
· Institute of Preventive Medicine and Public Health, Semmelweis University, Budapest, Hungary. [email protected].
· pubmed
Aging remains the foremost risk factor for cardiovascular and cerebrovascular diseases, surpassing traditional factors in epidemiological significance. This review elucidates the cellular and molecular mechanisms underlying vascular aging, with an emphasis on sex differences that...
Aging remains the foremost risk factor for cardiovascular and cerebrovascular diseases, surpassing traditional factors in epidemiological significance. This review elucidates the cellular and molecular mechanisms underlying vascular aging, with an emphasis on sex differences that influence disease progression and clinical outcomes in older adults. We discuss the convergence of aging processes at the macro- and microvascular levels and their contributions to the pathogenesis of vascular diseases. Critical analysis of both preclinical and clinical studies reveals significant sex-specific variations in these mechanisms, which could be pivotal in understanding the disparity in disease morbidity and mortality between sexes. The review highlights key molecular pathways, including oxidative stress, inflammation, and autophagy, and their differential roles in the vascular aging of males and females. We argue that recognizing these sex-specific differences is crucial for developing targeted therapeutic strategies aimed at preventing and managing age-related vascular pathologies. The implications for personalized medicine and potential areas for future research are also explored, emphasizing the need for a nuanced approach to the study and treatment of vascular aging.
Longevity Relevance Analysis
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The paper addresses the cellular and molecular mechanisms of vascular aging, with a focus on sex-specific differences that influence age-related cardiovascular and cerebrovascular diseases. While it contributes to understanding the complexities of aging and highlights the importance of personalized medicine, it primarily discusses mechanisms related to disease progression rather than directly targeting the root causes of aging or lifespan extension. Thus, it represents solid research but with limited impact on the broader field of longevity.
Runyang Feng, Shuangshuang Chen, Shichao Duan ...
· Sirtuins
· Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Cardiovascular Diseases, 180 Fenglin Road, Shanghai 200032, China.
· pubmed
Angiogenesis plays a pivotal role in ischemic cardiovascular disease, accompanied by epigenetic regulation during this process. Sirtuin 6 (SIRT6) has been implicated in the regulation of DNA repair, transcription and aging, with its deacetylase activity fully studied. However, th...
Angiogenesis plays a pivotal role in ischemic cardiovascular disease, accompanied by epigenetic regulation during this process. Sirtuin 6 (SIRT6) has been implicated in the regulation of DNA repair, transcription and aging, with its deacetylase activity fully studied. However, the role of SIRT6 demyristoylase activity remains less clear, with even less attention given to its myristoylated substrates. In this study, we report that endothelial specific SIRT6 knockout attenuated angiogenesis in mice, while SIRT6 was observed to promote migration and tube formation in endothelial cell. Notably, we further determined that SIRT6 affects the intracellular VEGFA and global myristoylation level under hypoxia. Moreover, ALK14 (myristic acids analogue) treatment and SIRT6 knockdown results in a significant decrease in VEGFA secretion under hypoxia, implying the involvement of SIRT6 demyristoylase activity in angiogenesis. Mechanistically, CLICK IT assay verified that VEGFA is a myristoylated substrate of SIRT6. Further, overexpression of SIRT6 mutants (R65A, G60A and H133Y) results in profound differences in VEGFA secretion, indicating that SIRT6 promotes VEGFA secretion through demyristoylation but not deacetylation. Finally, overexpression of SIRT6 rescued the diminishment of endothelial migration, tube formation and sprouting caused by ALK14 treatment. Overall, our study demonstrates that SIRT6 regulates angiogenesis by demyristoylating VEGFA and increasing VEGFA secretion. Therefore, modulation of SIRT6 demyristoylase activity may represent a therapeutic strategy for ischemic cardiovascular disease.
Longevity Relevance Analysis
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SIRT6 promotes angiogenesis by enhancing VEGFA secretion through its demyristoylation activity. The study addresses the role of SIRT6 in angiogenesis, which is linked to ischemic cardiovascular disease, a condition that can be influenced by aging processes, thus contributing to understanding mechanisms that may affect longevity.
Shea, J. M., Villeda, S. A.
· neuroscience
· University of California, San Francisco
· biorxiv
During aging, microglia, the resident macrophages of the brain, exhibit altered phenotypes and contribute to age-related neuroinflammation. While numerous hallmarks of age-related microglia have been elucidated, the progression from homeostasis to dysfunction during the aging pro...
During aging, microglia, the resident macrophages of the brain, exhibit altered phenotypes and contribute to age-related neuroinflammation. While numerous hallmarks of age-related microglia have been elucidated, the progression from homeostasis to dysfunction during the aging process remains unresolved. To bridge this gap in knowledge, we undertook complementary cellular and molecular analyses of microglia in the mouse hippocampus across the adult lifespan and in the experimental aging model of heterochronic parabiosis. Single-cell RNA-Seq and pseudotime analysis revealed age-related transcriptional heterogeneity in hippocampal microglia and identified intermediate states of microglial aging that also emerge following heterochronic parabiosis. We tested the functionality of intermediate stress response states via TGFB1 and translational states using pharmacological approaches in vitro to reveal their modulation of the progression to an activated state. Furthermore, we utilized single-cell RNA-Seq in conjunction with in vivo adult microglia-specific Tgfb1 conditional genetic knockout mouse models, to demonstrate that microglia advancement through intermediate aging states drives transcriptional inflammatory activation and hippocampal-dependent cognitive decline.
Longevity Relevance Analysis
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The paper investigates the aging process of microglia in the hippocampus and identifies intermediate states that contribute to cognitive decline, which is directly related to understanding the mechanisms of aging. By exploring the transition from homeostasis to dysfunction in microglia, the research addresses a fundamental aspect of age-related neuroinflammation and cognitive decline, making it relevant to longevity research. The findings provide important insights into the cellular mechanisms of aging, although they may not represent a groundbreaking breakthrough, hence the moderate impact score.
Yanping Ding, Chenxin Jiang, Lili Chen ...
· Saponins
· School of Life Sciences, Northwest Normal University, Lanzhou 730070, Gansu Province, China.
· pubmed
Various factors and mechanisms, including radiation, initiate cellular senescence and are concurrent with the progression of various neurodegenerative diseases. Radiation-induced chromosomal aberrations and DNA integrity damage impact the processes of cellular growth, maturation,...
Various factors and mechanisms, including radiation, initiate cellular senescence and are concurrent with the progression of various neurodegenerative diseases. Radiation-induced chromosomal aberrations and DNA integrity damage impact the processes of cellular growth, maturation, and aging. Astragaloside IV (AS-IV) has been documented to display significant neuroprotective effects on inflammation, oxidative stress, and cellular apoptosis; however, the precise neuroprotective mechanism of AS-IV against neuronal aging remains unclear. In this study, radiation-induced senescence models in C57BL/6 mice, PC12 cells, and primary neuronal cells were established. SA-β-gal histochemistry, flow cytometric analysis, immunofluorescence technique, and Western blotting analysis were employed to investigate the underlying mechanism of AS-IV in mitigating the aging of the brain cells caused by exposure to radiation. Our findings revealed that radiation exposure may activate the ERK pathway, leading to an increase in SA-β-gal-positive cells, elevated p21 levels, and the arrest of neuronal cells in the G1/S phase. However, AS-IV has been observed to mitigate the radiation-driven proliferation of senescent cells, by downregulating p-ERK and CDK2 expression and upregulating p21 and RB expression in treatment, thereby alleviating the aging and cognitive impairment caused by radiation. Additionally, evidence of U0126 treatment further supports these findings. In summary, our study showed that AS-IV could protect mice from radiation-induced cognitive impairment and reduce cellular senescence by regulating the ERK pathway.
Longevity Relevance Analysis
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Astragaloside IV mitigates radiation-induced neuronal senescence by regulating the ERK pathway. The study addresses mechanisms of cellular senescence and neuroprotection, which are directly related to aging processes and potential interventions for age-related cognitive decline.
Lajoyce Mboning, Emma K Costa, Jingxun Chen ...
· GeroScience
· Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, CA, USA.
· pubmed
Aging is a complex biological process influenced by various factors, including genetic and environmental influences. In this study, we present BayesAge 2.0, an upgraded version of our maximum likelihood algorithm designed for predicting transcriptomic age (tAge) from RNA-seq data...
Aging is a complex biological process influenced by various factors, including genetic and environmental influences. In this study, we present BayesAge 2.0, an upgraded version of our maximum likelihood algorithm designed for predicting transcriptomic age (tAge) from RNA-seq data. Building on the original BayesAge framework, which was developed for epigenetic age prediction, BayesAge 2.0 integrates a Poisson distribution to model count-based gene expression data and employs LOWESS smoothing to capture nonlinear gene-age relationships. BayesAge 2.0 provides significant improvements over traditional linear models, such as Elastic Net regression. Specifically, it addresses issues of age bias in predictions, with minimal age-associated bias observed in residuals. Its computational efficiency further distinguishes it from traditional models, as reference construction and cross-validation are completed more quickly compared to Elastic Net regression, which requires extensive hyperparameter tuning. Overall, BayesAge 2.0 represents a step forward in tAge prediction, offering a robust, accurate, and efficient tool for aging research and biomarker development.
Longevity Relevance Analysis
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The paper presents an upgraded algorithm for predicting transcriptomic age, which is directly related to understanding biological aging processes. By improving the accuracy and efficiency of age prediction from RNA-seq data, it contributes to the field of aging research and biomarker development. However, while it offers solid advancements over existing models, it does not introduce groundbreaking concepts or solutions that would significantly alter the trajectory of aging research, thus limiting its overall impact.
Yingxue Han, Zihuan Du, Hao Wu ...
· Aging cell
· State Key Laboratory of Animal Biotech Breeding, National Engineering Laboratory for Animal Breeding, Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture, College of Animal Science and Technology, China Agricultural University, Beijing, China.
· pubmed
With advancing age, significant changes occur in the female reproductive system, the most notable of which is the decline in oocyte quality, a key factor affecting female fertility. However, the mechanisms underlying oocyte aging remain poorly understood. In this study, we obtain...
With advancing age, significant changes occur in the female reproductive system, the most notable of which is the decline in oocyte quality, a key factor affecting female fertility. However, the mechanisms underlying oocyte aging remain poorly understood. In this study, we obtained oocytes from aged and young female mice and performed single-cell transcriptome sequencing, comparing our findings with existing proteomic analyses. Our analysis revealed that one of the primary characteristics of aging oocytes is the disruption of calcium ion homeostasis. Specifically, we identified two key genes involved in the oocyte aging process, Calb1 and Rpl23. Experimental validation demonstrated that knockdown of CALB1 in oocytes led to reduced calcium ion levels in the endoplasmic reticulum and mitochondria, resulting in mitochondrial dysfunction and meiotic defects. Further experiments suggested that RPL23 may function as a downstream gene of CALB1, and its knockdown caused mitochondrial dysfunction, excessive accumulation of reactive oxygen species (ROS), and spindle assembly defects. Notably, overexpression of these two genes in aging oocytes partially rescued the maternal age-related defective phenotypes, underscoring their crucial roles in oocyte aging. This study provides a comprehensive understanding of the specific mechanisms underlying mouse oocyte aging at single-cell resolution, supported by experimental validation, and offers new directions and potential targets for future research into age-related reproductive health issues.
Longevity Relevance Analysis
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The paper addresses the mechanisms underlying oocyte aging, which is a significant aspect of reproductive aging and has implications for female fertility. By identifying key genes involved in the aging process and demonstrating their roles in maintaining oocyte quality, the study contributes to understanding the biological processes of aging. However, while the findings are solid and provide a foundation for future research, they do not present a major breakthrough or transformative implications for the broader field of longevity research.
Frederic Català-Castro, Santiago Ortiz-Vásquez, Carmen Martínez-Fernández ...
· Nature nanotechnology
· ICFO-Institut de Ciències Fotòniques, Castelldefels, The Barcelona Institute of Science and Technology, Barcelona, Spain.
· pubmed
Quantifying the mechanical response of the biological milieu (such as the cell's interior) and complex fluids (such as biomolecular condensates) would enable a better understanding of cellular differentiation and aging and accelerate drug discovery. Here we present time-shared op...
Quantifying the mechanical response of the biological milieu (such as the cell's interior) and complex fluids (such as biomolecular condensates) would enable a better understanding of cellular differentiation and aging and accelerate drug discovery. Here we present time-shared optical tweezer microrheology to determine the frequency- and age-dependent viscoelastic properties of biological materials. Our approach involves splitting a single laser beam into two near-instantaneous time-shared optical traps to carry out simultaneous force and displacement measurements and quantify the mechanical properties ranging from millipascals to kilopascals across five decades of frequency. To create a practical and robust nanorheometer, we leverage both numerical and analytical models to analyse typical deviations from the ideal behaviour and offer solutions to account for these discrepancies. We demonstrate the versatility of the technique by measuring the liquid-solid phase transitions of MEC-2 stomatin and CPEB4 biomolecular condensates, and quantify the complex viscoelastic properties of intracellular compartments of zebrafish progenitor cells. In Caenorhabditis elegans, we uncover how mutations in the nuclear envelope proteins LMN-1 lamin A, EMR-1 emerin and LEM-2 LEMD2, which cause premature aging disorders in humans, soften the cytosol of intestinal cells during organismal age. We demonstrate that time-shared optical tweezer microrheology offers the rapid phenotyping of material properties inside cells and protein blends, which can be used for biomedical and drug-screening applications.
Longevity Relevance Analysis
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The paper presents a novel technique for measuring the viscoelastic properties of biological materials, which could contribute to understanding cellular differentiation and aging processes. However, while it touches on aging through the study of mutations related to premature aging disorders, it primarily focuses on mechanical properties rather than addressing the root causes of aging or lifespan extension. Thus, while it is solid research, its impact on the field of longevity is limited.
Mesa, K. R., O'Connor, K. A., Ng, C. ...
· immunology
· New York University School of Medicine
· biorxiv
All mammalian organs depend upon resident macrophage populations to coordinate repair processes and facilitate tissue-specific functions. Recent work has established that functionally distinct macrophage populations reside in discrete tissue niches and are replenished through som...
All mammalian organs depend upon resident macrophage populations to coordinate repair processes and facilitate tissue-specific functions. Recent work has established that functionally distinct macrophage populations reside in discrete tissue niches and are replenished through some combination of local proliferation and monocyte recruitment. Moreover, decline in macrophage abundance and function in tissues has been shown to contribute to many age-associated pathologies, such as atherosclerosis, cancer, and neurodegeneration. Despite these advances, the cellular mechanisms that coordinate macrophage organization and replenishment within an aging tissue niche remain largely unknown. Here we show that capillary-associated macrophages (CAMs) are selectively lost over time, which contributes to impaired vascular repair and tissue perfusion in older mice. To investigate resident macrophage behavior in vivo, we have employed intravital two-photon microscopy to non-invasively image in live mice the skin capillary plexus, a spatially well-defined model of niche aging that undergoes rarefication and functional decline with age. We find that CAMs are lost with age at a rate that outpaces that of capillary loss, leading to the progressive accumulation of capillary niches without an associated macrophage in both mice and humans. Phagocytic activity of CAMs was locally required to repair obstructed capillary blood flow, leaving macrophage-less niches selectively vulnerable to both homeostatic and injury-induced loss in blood flow. Our work demonstrates that homeostatic renewal of resident macrophages is not as finely tuned as has been previously suggested. Specifically, we found that neighboring macrophages do not proliferate or reorganize sufficiently to maintain an optimal population across the skin capillary niche in the absence of additional cues from acute tissue damage or increased abundance of growth factors, such as colony stimulating factor 1 (CSF1). Such limitations in homeostatic renewal and organization of various niche-resident cell types are potentially early contributors to tissue aging, which may provide novel opportunities for future therapeutic interventions.
Longevity Relevance Analysis
(4)
The paper investigates the loss of capillary-associated macrophages and its implications for vascular repair and tissue aging, addressing a potential root cause of aging-related decline in tissue function. This focus on macrophage behavior and its role in tissue aging is relevant to longevity research. However, while the findings are solid and contribute to understanding macrophage dynamics in aging, they do not present a major breakthrough or transformative implications for the field, thus warranting a moderate impact score.
Lu Mu, Ge Wang, Xuebing Yang ...
· Ovary
· State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing, China.
· pubmed
Ovarian function declines significantly as females enter middle-age, but the mechanisms underlying this decline remain unclear. Here, we utilize whole-organ imaging to observe a notable decrease in ovarian blood vessel (oBV) density and angiogenesis intensity of middle-aged mice....
Ovarian function declines significantly as females enter middle-age, but the mechanisms underlying this decline remain unclear. Here, we utilize whole-organ imaging to observe a notable decrease in ovarian blood vessel (oBV) density and angiogenesis intensity of middle-aged mice. This leads to a diminished blood supply to the ovaries, resulting in inadequate development and maturation of ovarian follicles. Utilizing genetic-modified mouse models, we demonstrate that granulosa cell secreted VEGFA governs ovarian angiogenesis, but the physiological decline in oBV is not attributed to VEGFA insufficiency. Instead, through single-cell sequencing, we identify the aging of the ovarian vascular endothelium as the primary factor contributing to oBV decline. Consequently, the administration of salidroside, a natural compound that is functional to reverse oBV aging and promote ovarian angiogenesis, significantly enhances ovarian blood supply and improve fertility in older females. Our findings highlight that enhancing oBV function is a promising strategy to boost fertility in females.
Longevity Relevance Analysis
(4)
The paper addresses the physiological mechanisms underlying ovarian aging and fertility decline, which are directly related to the aging process. By identifying the aging of ovarian blood vessels as a contributing factor and proposing a potential intervention to enhance fertility, it contributes to understanding and potentially mitigating aspects of aging. However, while the findings are solid and provide valuable insights, they do not represent a major breakthrough or transformative approach in the broader field of longevity research, thus warranting a moderate impact score.
Anastasia Gurinovich, Zeyuan Song, Harold Bae ...
· GeroScience
· Institute for Clinical Research and Health Policy Studies, Tufts Medical Center, Boston, MA, 02111, USA. [email protected].
· pubmed
Using whole-genome sequencing (WGS) might offer insights into rare genetic variants associated with healthy aging and extreme longevity (EL), potentially pointing to useful therapeutic targets. In this study, we conducted a genome-wide association study using WGS data from the Lo...
Using whole-genome sequencing (WGS) might offer insights into rare genetic variants associated with healthy aging and extreme longevity (EL), potentially pointing to useful therapeutic targets. In this study, we conducted a genome-wide association study using WGS data from the Long Life Family Study and identified a novel longevity-associated variant rs6543176 in the SLC9A2 gene. This SNP also showed a significant association with reduced hypertension risk and an increased, though not statistically significant, cancer risk. The association with cancer risk was replicated in the UK Biobank and FinnGen. Metabolomic analyses linked the rs6543176 longevity allele to higher serine levels, potentially associated with delayed mortality. Our findings warrant further investigation of SLC9A2's role in both longevity and cancer susceptibility, and they highlight the need for careful evaluation in developing anti-aging therapies based on EL-associated alleles.
Longevity Relevance Analysis
(4)
The paper identifies a genetic variant associated with extreme longevity and explores its implications for both longevity and cancer risk. While it contributes to the understanding of genetic factors in aging, the findings are primarily associative and do not directly address the mechanisms of aging or propose therapeutic interventions. Thus, it represents solid research but with limited impact on the field of longevity research.
Pradeep Ramalingam, Michael C Gutkin, Michael G Poulos ...
· Thrombospondin 1
· Division of Hematology and Oncology, Department of Medicine, University of Florida, Gainesville, FL 32610, USA.
· pubmed
Chronic low-grade inflammation observed in older adults, termed inflammaging, is a common feature underlying a multitude of aging-associated maladies including a decline in hematopoietic activity. However, whether suppression of inflammaging can preserve hematopoietic health span...
Chronic low-grade inflammation observed in older adults, termed inflammaging, is a common feature underlying a multitude of aging-associated maladies including a decline in hematopoietic activity. However, whether suppression of inflammaging can preserve hematopoietic health span remains unclear, in part because of a lack of tools to measure inflammaging within hematopoietic stem cells (HSCs). Here, we identify thrombospondin-1 (Thbs1) as an essential regulator of inflammaging within HSCs. We describe a transcriptomics-based approach for measuring inflammaging within stem cells and demonstrate that deletion of
Longevity Relevance Analysis
(4)
The paper addresses the role of thrombospondin-1 in regulating inflammaging within hematopoietic stem cells, which is directly related to the mechanisms of aging and longevity. By focusing on the suppression of chronic inflammation as a means to preserve hematopoietic health span, it contributes to understanding the root causes of aging rather than merely treating age-related diseases. However, while the findings are solid and contribute to the field, they do not represent a major breakthrough or transformative implications, thus warranting a moderate impact score.
Zhiqiang Li, Tianxiang Wang, Sijing Du ...
· Aging cell
· MOE Key Laboratory of Bioinformatics, Center for Synthetic and Systematic Biology, School of Life Sciences, Tsinghua University, Beijing, People's Republic of China.
· pubmed
Microglia, as resident immune cells in the central nervous system (CNS), play a crucial role in maintaining homeostasis and phagocytosing metabolic waste in the brain. Senescent microglia exhibit decreased phagocytic capacity and increased neuroinflammation through senescence-ass...
Microglia, as resident immune cells in the central nervous system (CNS), play a crucial role in maintaining homeostasis and phagocytosing metabolic waste in the brain. Senescent microglia exhibit decreased phagocytic capacity and increased neuroinflammation through senescence-associated secretory phenotype (SASP). This process contributes to the development of various neurodegenerative diseases, including Alzheimer's disease (AD). In this study, we found that SASP was elevated in senescent microglia, and proteomics showed that Tgm2 was upregulated. Mechanistically, we revealed that Tgm2-catalyzed covalent cross-linking of IκBα at K22 and Q248 residues in the cytoplasm of microglia, resulting in the reduction of IκBα and nuclear translocation of NF-κB to promote SASP production. Treatment of senescent microglia with Tgm2 inhibitors (Tg2-IN1 and Cys-D) resulted in reduced NF-κB nuclear translocation and decreased SASP. Additionally, oral administration of Cys-D significantly improved the aging phenotype in aged mice. To summarize, Tgm2 is a potential target for antiaging, and inhibitors of Tgm2 can serve as novel prophylactics or senomorphics.
Longevity Relevance Analysis
(4)
The paper investigates the role of Tgm2 in the context of senescent microglia and its impact on the senescence-associated secretory phenotype (SASP), which is relevant to the mechanisms of aging and neurodegeneration. While it identifies a potential target for intervention in aging processes, the findings appear to be more of a solid research contribution rather than a groundbreaking discovery. The implications for anti-aging therapies are promising but still preliminary, limiting the overall impact.
Lucas Paulo de Lima Camillo, Muhammad Haider Asif, Steve Horvath ...
· Aging
· School of Biological Sciences, University of Cambridge, Cambridge, UK.
· pubmed
Aging is a complex and multifaceted process involving many epigenetic alterations. One key area of interest in aging research is the role of histone modifications, which can dynamically regulate gene expression. Here, we conducted a pan-tissue analysis of the dynamics of seven ke...
Aging is a complex and multifaceted process involving many epigenetic alterations. One key area of interest in aging research is the role of histone modifications, which can dynamically regulate gene expression. Here, we conducted a pan-tissue analysis of the dynamics of seven key histone modifications during human aging. Our histone-specific age prediction models showed surprisingly accurate performance, proving resilient to experimental and artificial noise. Simulation experiments for comparison with DNA methylation age predictors revealed competitive performance. Moreover, gene set enrichment analysis uncovered several critical developmental pathways for age prediction. Different from DNA methylation age predictors, genes known to be involved in aging biology are among the most important ones for the models. Last, we developed a pan-tissue pan-histone age predictor, suggesting that age-related epigenetic information is degenerated across the epigenome. This research highlights the power of histone marks as input for creating robust age predictors and opens avenues for understanding the role of epigenetic changes during aging.
Longevity Relevance Analysis
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The paper investigates the role of histone modifications in aging, which is directly related to understanding the biological mechanisms of aging and potentially addressing its root causes. The development of age prediction models based on histone marks contributes to the field of aging research by providing insights into epigenetic changes associated with aging. However, while the findings are important, they do not represent a major breakthrough or transformative work that could significantly change the landscape of longevity research.
Mohanty, S. K., Sahu, V. K., Singh, B. P. ...
· biochemistry
· North Eastern Hill University
· biorxiv
Chronic kidney disease (CKD) presents a pressing global health challenge, characterized by progressive renal function decline and heightened morbidity and mortality. The interplay between CKD and hypothyroidism, particularly through the non-thyroidal low triiodothyronine (T3) syn...
Chronic kidney disease (CKD) presents a pressing global health challenge, characterized by progressive renal function decline and heightened morbidity and mortality. The interplay between CKD and hypothyroidism, particularly through the non-thyroidal low triiodothyronine (T3) syndrome, exacerbates disease progression and elevates mortality rates. Perturbations in the hypothalamic-pituitary-thyroidal (HPT) axis contribute to this scenario, while fibrotic kidneys exhibit diminished levels of the protective protein Klotho due to abnormal activation of the Wnt/{beta}-catenin pathway. Leveraging our previous findings showcasing T3's ability to downregulate aberrant Wnt/{beta}-catenin pathway activity by enhancing Klotho expression, both in vitro and in vivo, and Baicalein's direct inhibition of the Wnt pathway in C. elegans, we investigated Klotho's potential as a molecular link between CKD and hypothyroidism. Through experiments utilizing an adenine-induced CKD aged mouse model, we aimed to enhance Klotho expression via exogenous T3 administration and bidirectional Wnt pathway blockade using Baicalein (BAI). Our results demonstrate a significant synergistic upregulation of Klotho expression with combined T3 and BAI treatment, surpassing the effects of individual treatments. Moreover, this combination therapy effectively suppressed aberrant signaling molecules such as transforming growth factor beta (TGF), nuclear factor kappa B (NF{kappa}B), and glycogen synthase kinase 3 (GSK3), thus mitigating renal fibrosis. Improvements were observed in CKD-induced complications including cardiovascular disorders, dyslipidemia, and alterations in bone and serum markers. This unique bidirectional approach, targeting Klotho biology directly enhanced by T3 and sustained by T3 coupled with Wnt pathway blockade using BAI, presents a promising strategy for CKD management. Particularly relevant for elderly CKD patients with hypothyroidism, this approach holds potential to ameliorate renal degradation. Our findings underscore the substantial therapeutic promise of hormone and natural chemical interventions in CKD management.
Longevity Relevance Analysis
(4)
The paper addresses chronic kidney disease (CKD) and its relationship with hypothyroidism, focusing on Klotho, a protein associated with aging and longevity. By exploring a dual intervention strategy that targets underlying biological pathways rather than merely treating symptoms, it presents a potential approach to mitigate age-related renal decline. However, while the findings are solid and contribute to the understanding of CKD management in the context of aging, the impact is limited as it primarily focuses on a specific disease rather than broader mechanisms of aging or lifespan extension.
Dong, Z., Sepulveda, H., Vazquez, L. J. A. ...
· cancer biology
· Department of Signaling and Gene Expression, La Jolla Institute for Allergy and Immunology
· biorxiv
ASXL1 is one of the three most frequently mutated genes in age-related clonal hematopoiesis (CH), with the others being DNMT3A and TET2. CH can progress to myeloid malignancies including chronic monomyelocytic leukemia (CMML), and is also strongly associated with inflammatory car...
ASXL1 is one of the three most frequently mutated genes in age-related clonal hematopoiesis (CH), with the others being DNMT3A and TET2. CH can progress to myeloid malignancies including chronic monomyelocytic leukemia (CMML), and is also strongly associated with inflammatory cardiovascular disease and all-cause mortality in humans. DNMT3A and TET2 regulate DNA methylation and demethylation pathways respectively, and DNMT3A and TET2 loss-of-function mutations in CH reduce DNA methylation in heterochromatin, allowing de-repression of silenced elements in heterochromatin. In contrast, the mechanisms that connect mutant ASXL1 and CH are not yet fully understood. CH/CMML-associated ASXL1 mutations encode C-terminally truncated proteins that enhance the deubiquitinase activity of the ASXL-BAP1 ''PR-DUB '' deubiquitinase complex, which removes mono-ubiquitin from H2AK119Ub. Here we show that ASXL1 mutant proteins interact with the EHMT1-EHMT2 methyltransferase complex, which generates H3K9me1 and me2, the latter a repressive modification in constitutive heterochromatin. Compared to cells from age-matched wildtype mice, we found that expanded myeloid cells from old (>18-month-old) Asxl1tm/+ mice, a heterozygous knock-in mouse model of CH, display genome-wide decreases of H3K9me2, H3K9me3 and H2AK119Ub as well as an associated increase in expression of transposable elements (TEs) and satellite repeats. Increased TE expression was also observed in monocytes from ASXL1-mutant CMML patients compared to monocytes from healthy control individuals. Our data suggest that mutant ASXL1 proteins compromise the integrity of both constitutive and facultative heterochromatin in an age-dependent manner, by reducing the levels of H3K9me2/3 and H2AK119Ub respectively. The resulting increase in TE expression can alter the expression of nearby genes and promote the expression of inflammation-associated and interferon-inducible genes (ISGs).
Longevity Relevance Analysis
(4)
The paper investigates the role of mutant ASXL1 in clonal hematopoiesis and its connection to chronic monomyelocytic leukemia, highlighting mechanisms that may contribute to age-related genomic instability and inflammation. While it addresses a significant aspect of aging-related diseases, it primarily focuses on the pathology rather than directly targeting the root causes of aging or lifespan extension. The findings are solid and contribute to understanding the molecular mechanisms involved, but they do not represent a major breakthrough or transformative implications for longevity research.
Masaharu Uno, Masanori Nono, Chika Takahashi ...
· Caenorhabditis elegans
· Laboratory for Molecular Biology of Aging, RIKEN Center for Biosystems Dynamics Research (BDR), Hyogo, Japan.
· pubmed
During embryogenesis, organisms function as a robust system that ensures uniformity within individuals, but they lose robustness and develop variations at advanced ages. However, when and how organisms lose this robustness remains largely elusive. Here, we identified a sharp tran...
During embryogenesis, organisms function as a robust system that ensures uniformity within individuals, but they lose robustness and develop variations at advanced ages. However, when and how organisms lose this robustness remains largely elusive. Here, we identified a sharp transition from interindividual uniformity to diversity in the appearance and transcriptional features of age-matched Caenorhabditis elegans in midlife. Convolutional neural network analysis of individual appearance alterations revealed that the transition occurs in midlife, which coincides with the cessation of egg-laying activity and increased motility defects. This period represents the transition from the young state, marked by shared homogeneous features among same-age individuals, to the old state, marked by shared among old individuals. Transcriptional coherence within the age-matched individuals shows essentially the same transition, coinciding with the appearance features. These findings provide a new framework for understanding the aging trajectory in C. elegans, demonstrating the occurrence of the loss of robust control over appearance and transcriptional homeostasis in midlife.
Longevity Relevance Analysis
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The paper investigates the transition from uniformity to diversity in appearance and transcriptional features in Caenorhabditis elegans at midlife, which is relevant to understanding the aging process. It provides insights into how organisms lose robustness as they age, contributing to the broader field of aging research. However, while the findings are solid, they do not present a major breakthrough or transformative implications for longevity research, thus warranting a moderate impact score.
Chandra, J., Short, S., Rodriguez, F. ...
· radiology and imaging
· Massachusetts General Hospital
· medrxiv
Chronological age is a cornerstone of medical decision-making but is limited because individuals age at different rates. We recently released an open-source deep learning model to assess biological age from chest radiograph images (CXR-Age), which predicts incident all-cause and ...
Chronological age is a cornerstone of medical decision-making but is limited because individuals age at different rates. We recently released an open-source deep learning model to assess biological age from chest radiograph images (CXR-Age), which predicts incident all-cause and cardiovascular mortality better than chronological age. Here, we compare CXR-Age to two established epigenetic aging clocks (First generation- Horvath Age; Second generation- DNAm PhenoAge), to test which is more strongly associated with measures of cardiopulmonary disease. Our cohort consisted of 2,097 participants from the Project Baseline Health Study (PBHS), a prospective cohort study of individuals from four US sites enriched for cardiovascular and cardiometabolic disease risk factors. We found that CXR-Age was most strongly associated with the presence of coronary calcium, cardiovascular risk factors, worsening pulmonary function, increased frailty, and abundance in plasma of two proteins implicated in neuroinflammation and aging. Associations with second generation epigenetic clocks were weaker for pulmonary function and for all outcomes in younger adults. No associations were found with first generation clocks. These results suggest that opportunistic screening using CXR-Age may help identify high risk individuals who could benefit from directed screening and prevention.
Longevity Relevance Analysis
(4)
The paper is relevant to longevity research as it explores biological age assessment through deep learning and its associations with age-related subclinical diseases. It aims to improve risk stratification for cardiovascular and pulmonary conditions, which are significant in the context of aging. However, while the findings are solid and contribute to the understanding of biological age versus chronological age, the impact is limited as it primarily focuses on associations rather than addressing the root causes of aging or lifespan extension.
Cheng, S. F., Yue, W. L., Ng, K. K. ...
· neuroscience
· National University of Singapore
· biorxiv
Brain age has emerged as a powerful tool to understand neuroanatomical aging and its link to health outcomes like cognition. However, there remains a lack of studies investigating the rate of brain aging and its relationship to cognition. Furthermore, most brain age models are tr...
Brain age has emerged as a powerful tool to understand neuroanatomical aging and its link to health outcomes like cognition. However, there remains a lack of studies investigating the rate of brain aging and its relationship to cognition. Furthermore, most brain age models are trained and tested on cross-sectional data from primarily Caucasian, adult participants. It is thus unclear how well these models generalize to non-Caucasian participants, especially children. Here, we tested a previously published deep learning model on Singaporean elderly participants (55-88 years old) and children (4-11 years old). We found that the model directly generalized to the elderly participants, but model finetuning was necessary for children. After finetuning, we found that the rate of change in brain age gap was associated with future executive function performance in both elderly participants and children. We further found that lateral ventricles and frontal areas contributed to brain age prediction in elderly participants, while white matter and posterior brain regions were more important in predicting brain age of children. Taken together, our results suggest that there is potential for generalizing brain age models to diverse populations. Moreover, the longitudinal change in brain age gap reflects developing and aging processes in the brain, relating to future cognitive function.
Longevity Relevance Analysis
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The paper investigates the rate of brain aging and its association with executive function in diverse populations, which is relevant to understanding cognitive decline and aging processes. However, while it provides solid research on brain age models and their applicability to different age groups, the findings are incremental and do not significantly advance the field of longevity research or address the root causes of aging.
Yuting Wang, Wenhao Zhang, Chao Zhang ...
· Cell research
· Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA.
· pubmed
Aging is a process accompanied by functional decline in tissues and organs with great social and medical consequences. Developing effective anti-aging strategies is of great significance. In this study, we demonstrated that transplantation of young hematopoietic stem cells (HSCs)...
Aging is a process accompanied by functional decline in tissues and organs with great social and medical consequences. Developing effective anti-aging strategies is of great significance. In this study, we demonstrated that transplantation of young hematopoietic stem cells (HSCs) into old mice can mitigate aging phenotypes, underscoring the crucial role of HSCs in the aging process. Through comprehensive molecular and functional analyses, we identified a subset of HSCs in aged mice that exhibit "younger" molecular profiles and functions, marked by low levels of CD150 expression. Mechanistically, CD150
Longevity Relevance Analysis
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The paper addresses the role of hematopoietic stem cells in aging and presents findings that suggest a potential strategy for mitigating aging-related phenotypes through the transplantation of young HSCs. This research contributes to understanding the mechanisms of aging and offers insights into possible interventions, making it a solid contribution to the field. However, while it presents valuable findings, it does not represent a major breakthrough or transformative approach, thus the impact score is limited.
Yann Frey, Majd Haj, Yael Ziv ...
· Nucleic acids research
· The David and Inez Myers Laboratory for Cancer Research, Tel Aviv University, Tel Aviv 6997801, Israel.
· pubmed
Cellular senescence plays a significant role in tissue aging. Senescent cells, which resist apoptosis while remaining metabolically active, generate endogenous DNA-damaging agents, primarily reactive oxygen species. Efficient DNA repair is therefore crucial in these cells, especi...
Cellular senescence plays a significant role in tissue aging. Senescent cells, which resist apoptosis while remaining metabolically active, generate endogenous DNA-damaging agents, primarily reactive oxygen species. Efficient DNA repair is therefore crucial in these cells, especially when they undergo senescence escape, resuming DNA replication and cellular proliferation. To investigate whether senescent cell transcriptomes reflect adequate DNA repair capacity, we conducted a comprehensive meta-analysis of 60 transcriptomic datasets comparing senescent to proliferating cells. Our analysis revealed a striking downregulation of genes encoding essential components across DNA repair pathways in senescent cells. This includes pathways active in different cell cycle phases such as nucleotide excision repair, base excision repair, nonhomologous end joining and homologous recombination repair of double-strand breaks, mismatch repair and interstrand crosslink repair. The downregulation observed suggests a significant accumulation of DNA lesions. Experimental monitoring of DNA repair readouts in cells that underwent radiation-induced senescence supported this conclusion. This phenomenon was consistent across various senescence triggers and was also observed in primary cell lines from aging individuals. These findings highlight the potential of senescent cells as 'ticking bombs' in aging-related diseases and tumors recurring following therapy-induced senescence.
Longevity Relevance Analysis
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The paper addresses the downregulation of DNA repair genes in senescent cells, which is directly related to the mechanisms of aging and cellular senescence. By identifying a potential root cause of cellular dysfunction in aging, it contributes to understanding how senescent cells may influence age-related diseases. However, while the findings are solid and provide valuable insights, they do not represent a major breakthrough or transformative implications for the field, hence the moderate impact score.
Jing Wang, Chunshuang Li, Jinling Han ...
· Journal of biomedical science
· Department of Respiratory Medicine, China-Japan Union Hospital of Jilin University, Changchun, 130031, China.
· pubmed
ROS cause multiple forms of DNA damage, and among them, 8-oxoguanine (8-oxoGua), an oxidized product of guanine, is one of the most abundant. If left unrepaired, 8-oxoGua may pair with A instead of C, leading to a mutation of G: C to T: A during DNA replication. 8-Oxoguanine DNA ...
ROS cause multiple forms of DNA damage, and among them, 8-oxoguanine (8-oxoGua), an oxidized product of guanine, is one of the most abundant. If left unrepaired, 8-oxoGua may pair with A instead of C, leading to a mutation of G: C to T: A during DNA replication. 8-Oxoguanine DNA glycosylase 1 (OGG1) is a tailored repair enzyme that recognizes 8-oxoGua in DNA duplex and initiates the base excision repair (BER) pathway to remove the lesion and ensure the fidelity of the genome. The accumulation of genomic 8-oxoGua and the dysfunction of OGG1 is readily linked to mutagenesis, and subsequently aging-related diseases and tumorigenesis; however, the direct experimental evidence has long been lacking. Recently, a series of studies have shown that guanine oxidation in the genome has a conservative bias, with the tendency to occur in the regulatory regions, thus, 8-oxoGua is not only a lesion to be repaired, but also an epigenetic modification. In this regard, OGG1 is a specific reader of this base modification. Substrate recognition and/or excision by OGG1 can cause DNA conformation changes, affect chromatin modifications, thereby modulating the transcription of genes involved in a variety of cellular processes, including inflammation, cell proliferation, differentiation, and apoptosis. Thus, in addition to the potential mutagenicity, 8-oxoGua may contribute to tumor development and progression through the altered gene expression stemming from its epigenetic effects.
Longevity Relevance Analysis
(4)
The paper discusses the role of oxidative DNA damage, specifically 8-oxoGua, and its repair enzyme OGG1 in the context of tumorigenesis, linking it to mutagenesis and potential epigenetic modifications. While it addresses mechanisms that could contribute to aging-related diseases, it does not directly tackle the root causes of aging or propose solutions for lifespan extension. The findings are solid and contribute to our understanding of DNA repair and its implications in cancer, but the impact is limited as it primarily focuses on a specific aspect of tumorigenesis rather than broader aging mechanisms.
Xianjiang Ye, Ran Yang, Talha Riaz ...
· Caenorhabditis elegans
· College of Food Science, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China; National Research and Development Centre for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, China.
· pubmed
Porphyra haitanensis proteins (PHP) are natural proteins with various nutritional and biological values. This study was to analyze the composition, stability, and antioxidant activity of PHP before and after simulation gastrointestinal digestion (SGD). Caenorhabditis elegans was ...
Porphyra haitanensis proteins (PHP) are natural proteins with various nutritional and biological values. This study was to analyze the composition, stability, and antioxidant activity of PHP before and after simulation gastrointestinal digestion (SGD). Caenorhabditis elegans was used as the model to investigate the functional activity and potential mechanisms of action of the PHP digestion products (PHPDP). The results showed that PHP contained 16 amino acids and exhibited high thermal stability (up to 80 °C), but dimerization or fragmentation occurred in environments with pH 3 and pH 11. After digestion, PHP released 212 bioactive peptides, which significantly enhanced its antioxidant activity and improved the resistance of C. elegans to heat, oxidative, and ultraviolet stress. Furthermore, PHPDP improved oxidative stress in C. elegans and extended its lifespan by increasing antioxidant enzyme activity and reducing malondialdehyde, lipofuscin, and reactive oxygen species levels. The mechanism of action of PHPDP likely involved regulating the insulin signaling pathway through daf-2/daf-16 and modulating the expression of oxidative stress regulators skn-1 and sod-3, thereby enhancing the organism's stress resistance and extending lifespan. This study demonstrated that P. haitanensis could serve as a reliable protein source in daily life and provided a reference for its development and application as a functional food ingredient.
Longevity Relevance Analysis
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Porphyra haitanensis proteins enhance stress resistance and extend lifespan in Caenorhabditis elegans through antioxidant mechanisms. The study investigates the potential of natural proteins to influence aging processes and improve longevity, making it relevant to the field of longevity research.
Juewon Kim, Yunju Jo, Gyumin Lim ...
· Caenorhabditis elegans
· Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju, Republic of Korea.
· pubmed
The mechanisms underlying the impact of probiotic supplementation on health remain largely elusive. While previous studies primarily focus on the discovery of novel bioactive bacteria and alterations in the microbiome environment to explain potential probiotic effects, our resear...
The mechanisms underlying the impact of probiotic supplementation on health remain largely elusive. While previous studies primarily focus on the discovery of novel bioactive bacteria and alterations in the microbiome environment to explain potential probiotic effects, our research delves into the role of living Lactiplantibacillus (formerly known as Lactobacillus) and their conditioned media, highlighting that only the former, not dead bacteria, enhance the healthspan of Caenorhabditis elegans (C. elegans). To elucidate the underlying mechanisms, we conduct transcriptomic profiling through RNA-seq analysis in C. elegans exposed to GTB1, a strain of Lactiplantibacillus plantarum or 3-phenyllactic acid (PLA), mimicking the presence of key candidate metabolites of GTB1 and evaluating healthspan. Our findings reveal that PLA treatment significantly extends the healthspan of C. elegans by promoting energy metabolism and stress resilience in a SKN-1/ATFS-1-dependent manner. Moreover, PLA-mediated longevity is associated with a novel age-related parameter, the Healthy Aging Index (HAI), introduced in this study, which comprises healthspan-related factors such as motility, oxygen consumption rate (OCR), and ATP levels. Extending the relevance of our work to humans, we observe an inverse correlation between blood PLA levels and physical performance in patients with sarcopenia, when compared to age-matched non-sarcopenic controls. Our investigation thus sheds light on the pivotal role of the metabolite PLA in probiotics-mediated enhancement of organismal healthspan, and also hints at its potential involvement in age-associated sarcopenia. These findings warrant further investigation to delineate PLA's role in mitigating age-related declines in healthspan and resilience to external stressors.
Longevity Relevance Analysis
(4)
The paper investigates the role of a microbiota-derived metabolite, 3-phenyllactic acid, in enhancing healthspan and mitochondrial function in C. elegans, which is directly related to longevity research. It explores mechanisms that could potentially mitigate age-related declines in healthspan, making it relevant to the field. However, while the findings are solid and contribute to understanding the relationship between probiotics and healthspan, they are somewhat incremental and do not present groundbreaking insights that would significantly alter the current understanding of aging mechanisms.
Runping Duan, Loujing Jiang, Tianfu Wang ...
· Tumor Microenvironment
· State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, 510060, China.
· pubmed
Aging is associated with increased tumor metastasis and poor prognosis. However, how an aging immune system contributes to the process is unclear. Here, single-cell RNA sequencing reveals that in male mice, aging shifts the lung immune microenvironment towards a premetastatic nic...
Aging is associated with increased tumor metastasis and poor prognosis. However, how an aging immune system contributes to the process is unclear. Here, single-cell RNA sequencing reveals that in male mice, aging shifts the lung immune microenvironment towards a premetastatic niche, characterized by an increased proportion of IL-17-expressing γδT (γδ17) and neutrophils. Mechanistically, age-dependent downregulation of the immune trafficking receptor S1pr1 drives the expansion of γδ17. Compared to young mice, expanded γδ17 recruit tumor-promoting neutrophils with lower expression levels of CD62L and higher levels of C-kit and CXCR4. These neutrophils suppress the stemness and tumor-killing functions of CD8+ T cells in aged male mice. Accordingly, antibody-mediated depletion of γδT or neutrophils reduces tumor metastatic foci in aged animals, and the administration of the senolytic agent procyanidin C1 reverses the observed immune-mediated, tumor-promoting effects of aging. Thus, we uncover a γδ17-Neutrophil-CD8 axis that promotes aging-driven tumor metastasis in male mice and provides potential insights for managing metastatic tumors.
Longevity Relevance Analysis
(4)
The paper investigates the role of the aging immune system in promoting tumor metastasis, specifically through the γδ17-Neutrophil-CD8 axis. This research addresses mechanisms that contribute to age-related changes in immune function and their implications for cancer progression, which aligns with the broader goals of understanding aging and its effects on health. However, while the findings are solid and contribute to the understanding of cancer biology in the context of aging, they do not significantly advance the field in a transformative way, hence the moderate impact score.
Shinno, K., Miura, Y., Iijima, K. M. ...
· cell biology
· Tokyo Metropolitan University
· biorxiv
Neuronal aging and neurodegenerative diseases are accompanied by proteostasis collapse, while cellular factors that trigger it are not identified. Impaired mitochondrial transport in the axon is another feature of aging and neurodegenerative diseases. Using Drosophila, we found t...
Neuronal aging and neurodegenerative diseases are accompanied by proteostasis collapse, while cellular factors that trigger it are not identified. Impaired mitochondrial transport in the axon is another feature of aging and neurodegenerative diseases. Using Drosophila, we found that genetic depletion of axonal mitochondria causes dysregulation of protein degradation. Axons with mitochondrial depletion showed abnormal protein accumulation and autophagic defects. Lowering neuronal ATP levels by blocking glycolysis did not reduce autophagy, suggesting that autophagic defects are associated with mitochondrial distribution. We found that eIF2beta was increased by the depletion of axonal mitochondria via proteome analysis. Phosphorylation of eIF2alpha, another subunit of eIF2, was lowered, and global translation was suppressed. Neuronal overexpression of eIF2beta phenocopied the autophagic defects and neuronal dysfunctions, and lowering eIF2beta expression rescued those perturbations caused by depletion of axonal mitochondria. These results indicate the mitochondria-eIF2beta axis maintains proteostasis in the axon, of which disruption may underly the onset and progression of age-related neurodegenerative diseases.
Longevity Relevance Analysis
(4)
The paper addresses the role of mitochondrial distribution in maintaining neuronal autophagy and proteostasis during aging, which is directly related to the mechanisms underlying aging and age-related neurodegenerative diseases. While it provides solid insights into the mitochondrial-eIF2beta axis and its implications for neuronal health, the findings appear to be an incremental advance rather than a groundbreaking discovery. The research contributes to understanding the cellular processes involved in aging but does not propose a novel approach to directly combat aging itself.
Kai Shen, Hao Zhou, Qiang Zuo ...
· Mitochondria
· Department of Orthopaedics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China.
· pubmed
Accumulating evidence indicates that cellular senescence is closely associated with osteoarthritis. However, there is limited research on the mechanisms underlying fibroblast-like synoviocyte senescence and its impact on osteoarthritis progression. Here, we elucidate a positive c...
Accumulating evidence indicates that cellular senescence is closely associated with osteoarthritis. However, there is limited research on the mechanisms underlying fibroblast-like synoviocyte senescence and its impact on osteoarthritis progression. Here, we elucidate a positive correlation between fibroblast-like synoviocyte senescence and osteoarthritis progression and reveal that GATD3A deficiency induces fibroblast-like synoviocyte senescence. Mechanistically, GATD3A deficiency enhances the binding of Sirt3 to MDH2, leading to deacetylation and decreased activity of MDH2. Reduced MDH2 activity impairs tricarboxylic acid cycle flux, resulting in mitochondrial dysfunction and fibroblast-like synoviocyte senescence. Intra-articular injection of recombinant adeno-associated virus carrying GATD3A significantly alleviates the osteoarthritis phenotype in male mice. This study increases our current understanding of GATD3A function. In particular, we reveal a novel mechanism of fibroblast-like synoviocyte senescence, suggesting that targeting GATD3A is a potential therapeutic approach for osteoarthritis.
Longevity Relevance Analysis
(4)
The paper addresses the mechanisms of cellular senescence in fibroblast-like synoviocytes and its role in osteoarthritis progression, which is relevant to aging research as it explores a potential root cause of age-related joint degeneration. However, while it presents a novel mechanism and suggests a therapeutic target, the findings are more incremental than groundbreaking, limiting its overall impact on the field of longevity research.
Valeria Marasco, Winnie Boner, Kate Griffiths ...
· Finches
· Department of Interdisciplinary Life Sciences, Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Vienna, Austria.
· pubmed
Offspring of older breeders frequently show reduced longevity, which has been linked to shorter offspring telomere length. It is currently unknown whether such telomere reduction persists beyond a single generation, as would be the case if germline transmission is involved. In a ...
Offspring of older breeders frequently show reduced longevity, which has been linked to shorter offspring telomere length. It is currently unknown whether such telomere reduction persists beyond a single generation, as would be the case if germline transmission is involved. In a within-grandmother, multi-generational study using zebra finches, we show that the shorter telomeres observed in F1 offspring of older mothers are still present in the F2 generation even when the breeding age of their F1 mothers is young. The effect was substantial: 43% shorter telomeres in grandoffspring from the 'grandmother old at breeding' line compared with those from the 'grandmother young at breeding' line. Shorter telomeres at fledging in this species are associated with a reduction in lifespan. Our data demonstrate the need to look beyond a single generation to explain inter-individual variation in ageing rates and thereby variation in optimal allocation of age-specific reproductive effort.
Longevity Relevance Analysis
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The paper investigates the intergenerational effects of maternal breeding age on offspring telomere length, which is directly related to longevity and aging processes. It provides insights into how telomere length, a known biomarker of biological aging, can be influenced across generations, suggesting a potential root cause of aging variation. However, while the findings are solid and contribute to the understanding of aging mechanisms, they do not present a major breakthrough or transformative implications for the field, hence the moderate impact score.
Li Xu, Shuo Chen, Qiuling Fan ...
· BMC biology
· Department of Laboratory Medicine, The Second Affiliated Hospital of Guangdong Medical University, Zhanjiang, 524003, China.
· pubmed
Age-related kidney impairment, characterized by tubular epithelial cell senescence and renal fibrosis, poses a significant global public health threat. Although N6-methyladenosine (m6A) methylation is implicated in various pathological processes, its regulatory mechanism in kidne...
Age-related kidney impairment, characterized by tubular epithelial cell senescence and renal fibrosis, poses a significant global public health threat. Although N6-methyladenosine (m6A) methylation is implicated in various pathological processes, its regulatory mechanism in kidney aging remains unclear.
Longevity Relevance Analysis
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The paper investigates the role of N6-methyladenosine methylation in kidney aging, focusing on its regulatory mechanisms which could contribute to understanding the biological processes underlying aging and age-related diseases. While it addresses a significant aspect of aging, the findings appear to be more of a solid research contribution rather than a groundbreaking discovery, thus warranting a moderate impact score.
Mauricio Guillen-Parra, Jue Lin, Aric A Prather ...
· Telomerase
· Departamento de Ecología Evolutiva, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, México.
· pubmed
Telomere attrition is a hallmark of biological aging, contributing to cellular replicative senescence. However, few studies have examined the determinants of telomere attrition in vivo in humans. Mitochondrial Health Index (MHI), a composite marker integrating mitochondrial energ...
Telomere attrition is a hallmark of biological aging, contributing to cellular replicative senescence. However, few studies have examined the determinants of telomere attrition in vivo in humans. Mitochondrial Health Index (MHI), a composite marker integrating mitochondrial energy-transformation capacity and content, may be one important mediator of telomere attrition, as it could impact telomerase activity, a direct regulator of telomere maintenance. In this observational longitudinal study, we examined in peripheral blood mononuclear cells (PBMCs), whether MHI predicted changes in telomerase activity over a 9-month period, thus impacting telomere maintenance over this same period of time. We secondarily examined the role of chronic stress, by comparing these relationships in mothers of children with an autism spectrum disorder (caregivers) vs. mothers of a neurotypical child (controls). Here we show that both chronic stress exposure and lower MHI independently predicted decreases in telomerase activity over the subsequent 9 months. Finally, changes in telomere length were directly related with changes in telomerase activity, and indirectly with MHI and chronic stress, as revealed by a path analysis. These results highlight the potential role of chronic stress and MHI as drivers of telomere attrition in human PBMCs, through an impairment of both energy-transformation capacity and telomerase production.
Longevity Relevance Analysis
(4)
The paper investigates the relationship between mitochondrial health, telomerase activity, and telomere attrition, which are all critical factors in the biological aging process. By examining these relationships in the context of chronic stress, it provides insights into potential mechanisms underlying telomere maintenance and aging. However, while the findings are solid and contribute to the understanding of aging, they do not present groundbreaking advancements or novel interventions that could significantly alter the field of longevity research. Thus, the impact is rated as limited but still valuable.
Lucia Leitner, Martina Schultheis, Franziska Hofstetter ...
· Osteonectin
· Max Perutz Labs, Vienna Biocenter Campus (VBC), Vienna, Austria; Medical University of Vienna, Center for Medical Biochemistry, Department of Molecular Biology, Vienna, Austria.
· pubmed
The mammalian heart contains cardiac stem cells throughout life, but it has not been possible to harness or stimulate these cells to repair damaged myocardium in vivo. Assuming physiological relevance of these cells, which have evolved and have been maintained throughout mammalia...
The mammalian heart contains cardiac stem cells throughout life, but it has not been possible to harness or stimulate these cells to repair damaged myocardium in vivo. Assuming physiological relevance of these cells, which have evolved and have been maintained throughout mammalian evolution, we hypothesize that cardiac stem cells may contribute to cardiomyogenesis in an unorthodox manner. Since the intermediate filament protein desmin and the matricellular Secreted Protein Acidic and Rich in Cysteine (SPARC) promote cardiomyogenic differentiation during embryogenesis in a cell-autonomous and paracrine manner, respectively, we focus on their genes and employ mouse embryonic and cardiac stem cell lines as in vitro models to ask whether desmin and SPARC cooperatively influence cardiomyogenesis in cardiac stem and progenitor cells. We show that desmin also promotes cardiomyogenesis in a non-cell autonomous manner by increasing the expression and secretion of SPARC in differentiating embryonic stem cells. SPARC is also secreted by cardiac stem cells where it promotes cardiomyogenesis in an autocrine and concentration-dependent manner by upregulating the expression of myocardial transcription factors and its elicitor desmin. Desmin and SPARC interact genetically, forming a positive feedback loop and secreted autocrine and paracrine SPARC negatively affects sparc mRNA expression. Paracrine SPARC rescues cardiomyogenic desmin-haploinsufficiency in cardiac stem cells in a glycosylation-dependent manner, increases desmin expression, the phosphorylation of Smad2 and induces the expression of gata4, nkx2.5 and mef2C. Demonstration that desmin-induced autocrine secretion of SPARC in cardiac stem cells promotes cardiomyogenesis raises the possibility that a physiological function of cardiac stem cells in the adult and aging heart may be the gland-like secretion of factors such as SPARC that modulate age-related and adverse environmental influences and thereby contribute to cardiac homeostasis throughout life.
Longevity Relevance Analysis
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The paper claims that desmin-induced autocrine secretion of SPARC in cardiac stem cells promotes cardiomyogenesis. This research is relevant as it explores mechanisms that may contribute to cardiac homeostasis and repair in the aging heart, addressing potential root causes of age-related cardiac decline.
Yuanyuan Li, Yuxiu Lin, Zhi Chen ...
· Activating Transcription Factor 2
· State Key Laboratory of Oral & Maxillofacial Reconstruction and Regeneration, Key Laboratory of Oral Biomedicine Ministry of Education, Hubei Key Laboratory of Stomatology, School & Hospital of Stomatology, Wuhan University, Wuhan 430079, China.
· pubmed
The aging process is associated with a loss of bone mass and an accumulation of senescent cells, which is under epigenetic control. Morphological and molecular analysis revealed a notable reduction in bone mass and alveolar crest height in aged mice, accompanied by increased leve...
The aging process is associated with a loss of bone mass and an accumulation of senescent cells, which is under epigenetic control. Morphological and molecular analysis revealed a notable reduction in bone mass and alveolar crest height in aged mice, accompanied by increased levels of senescent mouse jaw bone marrow stem cells (mJBMSCs). To investigate whether specific transcription factors are involved, assay for transposase-accessible chromatin with sequencing (ATAC-seq) was performed on mJBMSCs isolated from 2-, 4-, 8-, and 20-month-old mice. In 20-month-old mJBMSCs, increased chromatin accessibility was observed alongside elevated expression of activating transcription factor 2 (ATF2) in both cells and alveolar bone. Silencing Atf2 in mJBMSCs failed to reverse physiological aging, but delayed replication stress and pamidronate (PAM) induced senescence. The analysis of ATAC-seq and RNA sequencing indicated that the differentially expressed genes upregulated by PAM but downregulated by ATF2 deficiency were related to some key biological processes, including negative regulation of cell proliferation, inflammatory response, adipogenesis, and cellular senescence. The dual-luciferase assay was conducted to demonstrate that ATF2 enhances Cdkn2a transcription by binding to its promoter region. Our findings suggest significant chromatin alterations in aged mJBMSCs, positioning ATF2 as a potential target for combating externally induced senescence.
Longevity Relevance Analysis
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The paper claims that deficiency of ATF2 can delay senescence induced by replication stress and pamidronate in mouse jaw bone marrow stem cells. This research addresses the mechanisms of cellular senescence and potential interventions, which are central to understanding and potentially mitigating aspects of the aging process.
Bass, C., Bharath, A. A., De Paola, V.
· neuroscience
· Imperial College London
· biorxiv
How aging affects axon regeneration and synaptic repair in the brain is poorly understood. To study age-related changes in neural circuits, we developed a model of axonal injury in the aged (> 2 years) mouse somatosensory cortex. By directly tracking fluorescently labelled injure...
How aging affects axon regeneration and synaptic repair in the brain is poorly understood. To study age-related changes in neural circuits, we developed a model of axonal injury in the aged (> 2 years) mouse somatosensory cortex. By directly tracking fluorescently labelled injured axons by multiphoton imaging, we find that while axon degeneration in the aged brain is comparable to the young adult brain, axon regeneration is impaired. We further examine changes in the most common type of cortical synapses, En Passant Boutons (EPBs), and observe a transient and significant increase in the number and size of boutons 6 hours post-lesion. Using a computational model of a recurrent neural network, we examined the functional consequences of these synaptic increases on memory, comparing results to models of the young adult brain. The results suggest that increased synaptic dynamics might enable partial recovery from injury via synaptic re-wiring in the aged brain.
Longevity Relevance Analysis
(4)
The paper investigates age-related changes in axon regeneration and synaptic dynamics, which are critical aspects of understanding the aging process in the brain. While it provides solid research on the mechanisms of neural repair in aged mammals, the findings primarily contribute to the understanding of age-related changes rather than addressing the root causes of aging or lifespan extension. Thus, while it is relevant to longevity research, its impact is limited as it does not propose significant advancements or solutions to aging itself.
Yuan Li, Weiguo Fan, Tzu-Han Lo ...
· Src Homology 2 Domain-Containing, Transforming Protein 1
· Division of Gastroenterology and Hepatology, Stanford University, Stanford, California; Palo Alto VA Medical Center, Palo Alto, California.
· pubmed
Mitochondrial maladaptation and dysfunction contribute to the progression of metabolic dysfunction-associated steatohepatitis (MASH). Induction of Shc is implicated in progressive MASH during aging and the cytoplasmic p52Shc isoform in the activation of redox enzyme NOX2. The mit...
Mitochondrial maladaptation and dysfunction contribute to the progression of metabolic dysfunction-associated steatohepatitis (MASH). Induction of Shc is implicated in progressive MASH during aging and the cytoplasmic p52Shc isoform in the activation of redox enzyme NOX2. The mitochondrial Shc isoform p46Shc represses acetyl-coenzyme A acyltransferase 2 (ACAA2) in vitro. ACAA2 is a key enzyme for lipid β-oxidation; however, the metabolic consequences of in vivo p46Shc induction are unknown. In the current study, p46Shc-inducible mice were generated; these and littermate controls were aged and fed chow or fast-food (high-fat and high-fructose) diet. p46Shc induction increased liver injury, inflammation, and lipid peroxidation. p46Shc overexpression did not significantly change liver triglycerides. On electron microscopy studies, mitochondria were swollen with aberrant cristae. p46Shc induction reduced mitochondrial oxygen consumption as measured by Oroboros, as well as suppressed the production of β-hydroxybutyrate, the central metabolite of therapeutic ketosis. Mitochondria exhibited increased production of reactive oxidative species. By contrast, the expression of dominant negative p46Shc reduced ACAA2 thiolase activity, improved β-oxidation, and reduced lipid peroxidation and production of reactive oxidative species. In summary, these studies support the concept that p46Shc induction in aging represses ACAA2, resulting in decreased mitochondrial β-oxidation and increased lipid peroxidation. Maintaining β-oxidation and ketogenesis could prevent liver injury, and targeting Shc-related maladaptive responses could be a successful therapeutic strategy in aging/MASH.
Longevity Relevance Analysis
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The paper claims that p46Shc induction in aging represses ACAA2, leading to decreased mitochondrial β-oxidation and increased lipid peroxidation. This research is relevant as it addresses the underlying mechanisms of mitochondrial dysfunction in aging, which is a critical aspect of age-related diseases and potential interventions for longevity.
Xinxin Fan, Yu Lu, Yujun Xie ...
· Polysaccharides
· Jiangsu Provincial Key Laboratory of TCM Evaluation and Translational Research, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing 211198, China; Laboratory of Molecular Life Sciences, Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
· pubmed
Anemarrhena asphodeloides Bge. (AAB), a traditional medicinal herb, has a long history of delaying the aging process. Yet, the anti-aging effects of its polysaccharides have not been thoroughly investigated. This study marks the first exploration of the anti-aging activity of Ane...
Anemarrhena asphodeloides Bge. (AAB), a traditional medicinal herb, has a long history of delaying the aging process. Yet, the anti-aging effects of its polysaccharides have not been thoroughly investigated. This study marks the first exploration of the anti-aging activity of Anemarrhena asphodeloides Bge. polysaccharides (AABP). The MW of AABP-1a was determined to be 210.062 kDa, with a composition consisting predominantly of glucose and mannose in a molar ratio of approximately 4:1. The backbone of AABP-1a was mainly composed of →4)-2Ac-β-Man(1→ and →4)-β-Glc(1→ and a small amount of branched →4,6)-β-Glc(1→ and →3,4)-β-Glc(1→, the branching part was composed of →6)-β-Glc(1→ and t-α-Glc(1→. AABP-1a has antioxidant capacity and can improve cell cycle arrest mediated by senescence markers such as p53, p21, p16 and SASP, and reduce the accumulation of damaged DNA. In addition, it could reduce the activity of SA-β-Gal in zebrafish, prolong the lifespan of C. elegans and reduce the expression of lipofuscin. This study found a glucomannan and demonstrated its anti-aging activity in various aging models. These results provide a theoretical basis for further study of the anti-aging effect of AAB.
Longevity Relevance Analysis
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The paper claims that polysaccharides from Anemarrhena asphodeloides Bge. exhibit anti-aging activity by improving cell cycle arrest and reducing markers of senescence. The study investigates a natural compound's potential to influence aging processes, which aligns with longevity research.