Bamboo Leaf Flavonoids Suppress Oxidative Stress-Induced Senescence of HaCaT Cells and UVB-Induced Photoaging of Mice through p38 MAPK and Autophagy Signaling

With the global escalation of the aging process, the research on aging mechanisms and anti-aging strategies has become a hot spot. As the most external organ of the human body, skin can be used as an ideal organ for the study of endogenous and exogenous aging. Bamboo leaf flavonoids (BLF) possess a variety of biological effects such as antioxidant, anti-bacterial, anti-inflammatory, lipid-lowering, anti-radiation, and anti-aging. However, it is still unclear whether they can delay skin aging. This study aimed to analyze the inhibitory effect of BLF on skin aging and explore their molecular mechanisms. We found that 10-40 μg/mL BLF significantly inhibited the senescence of HaCaT cells induced by AAPH, which might be related to their antioxidant and anti-inflammatory abilities. Further mechanism studies showed that mitogen-activated protein kinase (MAPK), especially the p38 MAPK pathway, was the key to BLF to alleviate the senescence of HaCaT cells. In addition, autophagy was also involved in the anti-senescence effect of BLF. The results were also verified in UVB-induced photoaging mice. Therefore, BLF can be used as a potential therapeutic agent to intervene skin aging in vitro and in vivo.