Photoprotective effect of Astragalus membranaceus polysaccharide on UVA-induced damage in HaCaT cells

The skin provides a predominant barrier against chemical, physical and microbial incursion. The intemperate exposure to ultraviolet A (UVA) radiation can cause excessive cellular oxidative stress, leading to skin damage, proteins damage and mitochondrial dysfunction. There is sufficient evidences supporting the proposal that mitochondria is highly implicated in skin photo-damage. In the present study, a polysaccharide isolated from Astragalus membranaceus was further purified to be an [alpha]-glucan, which was further investigated its beneficial influence on UVA-induced photo-damage in HaCaT cells. Our results showed that the purified Astragalus membranaceus polysaccharide (AP) can protect HaCaT cells from UVA-induced photo-damage through reducing UVA-induced intracellular ROS production and mitochondrial membrane potential, thereby altering ATP content. It was found that the UVA induced damage in HaCaT cells could be effectively restored by co-treatment with AP. AP exhibited promising potential for advanced application as multifunctional skin care products and drugs.