Protective Effects of Centella asiatica Against Senescence and Apoptosis in Epidermal Cells

Centella asiatica, a traditional medicinal plant, possesses potent antioxidant activity and may therefore prevent cellular aging and exert antiapoptotic effects. However, these effects remain to be fully elucidated. This study aimed to investigate the protective effects of C. asiatica extract against cellular senescence and apoptosis caused by hydrogen peroxide (H₂O₂)-induced oxidative stress in human epidermal keratinocytes (HaCaT cells). To evaluate the effects of H₂O₂ and C. asiatica on HaCaT cells, we measured cell viability as a marker of cell death; reactive oxygen species (ROS), radical scavenging, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase activities as markers of oxidative stress; senescence-associated β-galactosidase (SA-β-gal) activity as a marker of cellular senescence; and caspase-3/9 activities and apoptotic cells as markers of apoptosis. H₂O₂ induced cell death (decreased cell viability), oxidative stress (increased ROS activity, decreased radical scavenging, SOD, GPx, and catalase activities), cellular senescence (increased SA-β-gal activity), and apoptosis (increased early/late apoptotic cells and increased caspase-3/9 activities). C. asiatica significantly decreased all markers of H₂O₂-induced cell death, oxidative stress, cellular senescence, and apoptosis, suggesting its ability to prevent cellular senescence and apoptosis through its antioxidant activity. This mechanism of action may contribute to the prevention and improvement of skin aging.