The Protective Effect Of Glycyrrhiza Extract UVB Radiated Photoaging Of BALB/c Mice Skin

Objective:To explore the protective effect and possible mechanism of Glycyrrhiza, Rhodiola rosea, Codonopsis, Astragalus extracts on anti-UVB photoaging mice.①To research the protective effect of extractive of Glycyrrhiza, Rhodiola rosea, Codonopsis, Astragalus on UVB radiated BALB/c mice skin;②To study the four drugs'influence on the expression of SOD, MDA, TNF-a in photoaging model mice;③To observe the effects of apoptosis in skin tissue of UVB radiated BALB/c mice.Methods:66 BALB/c mice were randomly divided into 11 groups,6 mice in each group, mice back hair were shaved for 2 cm×3cm, the shaving area were topical used 5% or 10% water solution of Glycyrrhiza, Rhodiola rosea, Codonopsis, Astragalus extract 0.5ml, after 20min, 500mJ/cm2 UVB was radiated, per day, continue 1 month, the experiment the end, the mouse were sacrificed by cervical dislocation, visual observation the changes of back skin of mice, Histology of skin samples was researched by HE staining; Xanthine oxidase and thiobarbituric acid colorimetry are used respectively measurement SOD and MDA levels of the back skin of mice; TNF-a was measured by ELISA; SOD expression of skin tissues was observed by immunohistochemical staining; Apoptotic cells was detected by TUNEL.Results:After Chronic UV radiation, redness, pigmentation, thickening, shrinkage, scaling changes was appeared on back skin of mice by visual observation; However, these appearances were not obvious in the drug treatment group; the epidermis became parakeratosis and thickening and formation focal sponge, edema was seen under the epidermis and dense lymphocytes are infiltrate in the dermis layer and perivascular by HE staining; but pathological form of the drug treatment group compared with the control group changed little; In the drug treatment groups, SOD activity were higher than that in the ultraviolet radiation group, while MDA content were much lower (P<0.05), especially 5% Glycyrrhiza (P<0.01); The TNF-αexpression and apoptosis index were increased in the only ultraviolet radiation group, however, both of them were decreased in the drug treatment group (P<0.05).Conclusions:Chronic UVB radiation can lead to photoaging phenomenon and apoptosis in BALB/c mice skin; Topical application of the solution of extract of Glycyrrhiza, Rhodiola rosea, Codonopsis and Astragalus have protection effect on photoaging and apoptosis by UV induced mice skin, especially 5% Glycyrrhiza, with Rhodiola rosea followed. The protective effect may be related to the production of SOD, MDA and TNF-a, which can reduce apoptosis.