Preliminary Exploration Of Licorice Falconoid Protective Effect On UVB Damage And Impact On ERS Related Regulatory Molecules

ObjectiveTo investigate the effects of topical use of licorice flavonoids on photoaging mice skin which is induced by medium-wave ultraviolet B (UVB) irradiation, and its impact on stress related regulatory molecules in the endoplasmic reticulum, and discuss the intervention effect of licorice flavonoids on photoaging mouse skin induced by UVB radiation, find out the possible pathway of endoplasmic reticulum stress.MethodsFiftyBALB/C mice were randomly divided into5groups:photoaging model (A), model plus matrix group (B), licorice flavonoids group (C), sunscreen group(D),normal control group (E).The mouse model of photoaging skin was established by UVB radiation. Matrix cream, licorice falconoid cream, sun screen (SPF30, PA+++) were respectively used on mouse back in groups of B,C and D before UVB radiated. Histological sections stained with HE were used for observing the structural changes in skin, ELISA detect caspasse-3, caspase-12, CHOP.ResultsAfter UVB rays radiate, the group A and B compared with E group in mice skin tissue general morphology:skins manifest photoaging state, rough, thickened, scaling, erythematic; skin biopsy manifest that epidermal structure is not quite complete, stratum corneum ismarked thickening, dermis sebaceous glands show irregular hyperplasia, fibrous tissue is disorganized, often breakage and meanwhile inflammatory cells are infiltrated; the group A and B compared with E group, caspasse-3, caspase-12CHOP expression content in skin tissue increased significantly. The group C and D are compared with E group in mice skin tissue general morphology:The skin surface smooth, group C has a small amount of desquamation and pigmentation uneven; skin tissue biopsy performance is the structural integrity of the epidermis, thin cuticle and clear layers of cells, visible more obvious epidermal papillae, the papillary dermis. Wavy fibrous tissue uniformly distributed in dermis. The differences in caspasse-3, caspase-12and chop expression level has no statistically significant in C, D, and E groups (p>0.05).ConclusionLicorice flavonoids has a protective effect in photoaging mouse skin caused by UVB irradiation. The mechanism may be as follows:Firstly, the licorice flavonoids have antioxidant, can remove free radicals, and secondly, licorice flavonoids inhibits the activation of caspase-12,CHOP, thereby blocks the caspase-3activation, and inhibits cell apoptosis.