Protection of skin from UVB-induced photoaging: Antioxidant and anti-inflammatory effects of avenanthramide C from oat sprout extract via suppression of MAPK pathways.

Abstract

Ultraviolet B (UVB) radiation contributes to skin aging and damage via increasing oxidative stress and mediating inflammatory process in skin. The identification of effective agents to protect UVB-mediated deterioration against skin is necessitated. This study aims to examine the protective effects and mechanisms of avenanthramide C (AVN C), a phenolic compound enriched in oat sprout extract (Avena sativa), against UVB-induced photoaging in human keratinocyte cells (HaCaT) and a 3D reconstructed human skin model (Neoderm-ED). AVN C reduced oxidative stress by promoting the nuclear translocation of nuclear factor erythroid-2-related factor 2 (Nrf2) and upregulating antioxidant enzyme expression. AVN C also suppressed the production of inflammatory mediators, including COX-2, IL-1β, and TNF-α, through the inhibition of nuclear factor-kappa B (NF-κB) and upstream MAPK signaling. Moreover, AVN C inhibited UVB-induced matrix metalloproteinase (MMP)-1 and MMP-3 expression, thus preventing extracellular matrix degradation and wrinkle formation. In Neoderm-ED, AVN C protected against UVB-induced structural damage and inflammation by suppressing prostaglandin E