Vanadyl Complexes (VOp-Dmada) Promote Healthy Aging by Regulating Electron Transport Mediated by Mitochondrial Complex II.

Abstract

Vanadium compounds are promising metallodrug candidates, with well-documented antidiabetic, antitumor, and anti-Alzheimer's activities. In search for the long-term beneficial or adverse effects of antidiabetic vanadyl complexes, we serendipitously discovered that the vanadyl complexes VOp-dmada exerted pro-healthy aging effects across a diverse panel of model organisms, i.e., yeast, C. elegans, and SAMP8 mice. Furthermore, VOp-dmada attenuated replicative senescence in mouse embryonic fibroblasts and alleviated thymic epithelial cell aging while preserving thymic architecture and function in a mouse model of dexamethasone-induced acute thymic atrophy. Mechanistic investigations revealed that VOp-dmada improved the structural integrity and functional capacity of mitochondrial complex II. This effect was mediated by activation of the c-Myc/S-phase kinase-associated protein 2 (SKP2)/sirtuin 3 (SIRT3) signaling axis, which in turn upregulated succinate dehydrogenase subunit A (SDHA) expression. Thus, vanadyl complexes suppressed reactive oxygen species (ROS) generation at the source, disrupted the deleterious ROS-thioredoxin-interacting protein (TXNIP) vicious cycle, and ultimately decelerated the aging process. Our findings highlight the potential application of antidiabetic vanadium complexes in the treatment of other aging-related disorders and corroborate the chronic safety profile. Moreover, these results support the targeting of mitochondrial complex II function and integrity as a novel strategy for the discovery of pro-healthy aging agents.