Protective Action of Curcumin and Alpha-Lipoic Acid, Against Experimental Ultraviolet-a/B Induced Dermal-Injury in Rats

Abstract

The objective of this study was to examine the therapeutic efficacy of curcumin (CUR) and alpha-lipoic acid (ALA) in mitigating UV-A and UV-B-induced damage (UVAB) in rat dorsal skin. This was achieved through the utilisation of immunohistochemical (TUNEL), biochemical and stereological techniques. The rats in the UVAB, UVAB + CUR, and UVAB + ALA groups were subjected to UVAB irradiation for a period of two hours per day over the course of one month. The UVAB + CUR and UVAB + ALA groups were administered 100 mg/kg/day of curcumin and 100 mg/kg/day of alpha-lipoic acid via gavage 30 min prior to UVAB irradiation. The CUR group was administered 100 mg/kg/day of curcumin via gavage, while the ALA group received the same dose of alpha-lipoic acid. A significant change in the volume ratio of the dorsal skin epidermis and dermis was observed in the stereological findings of the rats in the UVAB group. These changes exhibited a favourable progression as a consequence of the CUR and ALA applications. In the UVAB group, TOS and OSI were significantly elevated as a consequence of the rise in oxidative stress. Conversely, the treatment groups demonstrated a notable reduction in TOS and OSI levels. The study also revealed a substantial increase in the number of apoptotic cells within the UVAB group. However, the treatment groups exhibited a significant decline in apoptotic cells. In conclusion, the findings suggest that CUR and ALA possess a protective effect against UVAB-induced skin damage.Graphical AbstractUltraviolet Irradiation to Rat Dorsal Skin