Preventive effect of andrographolide against ultraviolet‐B radiation‐induced oxidative stress and apoptotic signaling in human dermal fibroblasts.

Ultraviolet radiation induces oxidative photoaging in the skin cells. In this study, we investigated the ability of andrographolide (ADP) to protect human dermal fibroblasts (HDFa) from UVB radiation‐induced oxidative stress and apoptosis. The HDFa cells were exposed to UVB (19.8 mJ/cm2) radiation in the presence or absence of ADP (7 μM) and then oxidative stress and apoptotic protein expression were analyzed. UVB exposure resulted in a significant decline in the activity of antioxidant enzymes and altered mitochondrial membrane potential (MMP). Furthermore, UVB‐irradiation causes increased intracellular reactive oxygen species (ROS) production, apoptotic morphological changes, and lipid peroxidation levels in the HDFa. Moreover, the pretreatment with ADP reduced the UVB‐induced cytotoxicity, ROS production, and increased antioxidant enzymes activity. Further, the ADP pretreatment prevents the UVB‐induced loss of MMP and apoptotic signaling in HDFa cells. Therefore, the present results suggest that ADP protects HDFa cells from UVB‐induced oxidative stress and apoptotic damage. Significance statement: Andrographolide (ADP) exhibits potent antioxidant in the in vitro free radical scavenging activity and it prevents UVB‐induced oxidative stress and apoptotic signaling in human dermal fibroblasts. Further, we suggest that the ADP pretreatment predominantly protects against UVB‐induced cytotoxicity, lipid peroxidation, antioxidant depletion, and apoptotic molecules. In this study, ADP possesses antioxidant effects; it could help to develop photoprotective and new sunscreen agents. [ABSTRACT FROM AUTHOR]