ErZhiFormula prevents UV-induced skin photoaging by Nrf2/HO-1/NQO1 signaling: An in vitro and in vivo studies

Ethnopharmacological relevance: ErZhiFormula (EZF) is a classical traditional Chinese medicinal formulation. It can be used to treat liver and kidney yin deficiency, dizziness, lumbar debility, insomnia, nocturnal emission, lower extremity weakness, and other aging-related diseases. However, the protective effect of EZF in skin photoaging and its potential mechanism has not been clarified.Aim of the study: This study aims to explore the role of EZF in the skin photoaging mechanism induced by UV radiation.Materials and methods: Ultra Performance Liquid Chromatography (UPLC) was used to identify the fingerprint of EZF. The mice were irradiated with UVA and UVB to establish the photoaging model in vivo. Human immor-talized keratinocytes (HaCaT) were irradiated with UVB to establish the photoaging model in vitro. The activity of cells was detected by CCK-8 and LDH kits, the level of reactive oxygen species was detected by DCF fluorescent probe, and the apoptosis was detected by PE annexin V and 7-Amino-Actinomycin (7-AAD) staining. Comet assay was used to detect cell DNA damage. The antioxidant enzyme levels in cell and mouse serum were detected by antioxidant kit, and Western blot was used to detect protein expression.Results: We found that EZF contain many active ingredients, including salidroside, specnuezhenide, isoquercitrin, etc. EZF can improve the photoaging of HaCaT cells and mouse skin caused by UV radiation. The results of animal experiments are consistent with those of cell experiments. Combined with Western blot analysis, we found that EZF finally played an anti-skin photoaging role by regulating the Nrf2/HO-1/NQO1 pathway.Conclusions: EZF can protect skin from UV-induced photoaging by regulating the Nrf2/HO-1/NQO1 signal pathway. EZF may become a traditional Chinese medicine with the potential to prevent skin photoaging.

Automated summary

This study aims to explore the role of ErZhiFormula (EZF) in the mechanism of skin photoaging induced by UV radiation. The fingerprint of EZF was identified using Ultra Performance Liquid Chromatography (UPLC), and photoaging models were established in mice and human immortalized keratinocytes (HaCaT). The results showed that EZF can improve UV-induced photoaging in HaCaT cells and mouse skin by regulating the Nrf2/HO-1/NQO1 pathway.