Anti-Skin Aging Effect Of Total Flavonoids From Inula Britannica On Aging Mouse Model Induced By D-Galactose

Part one To explore the optimal concentration of D- galactose of aging mice modelObjective: To explore the optimal concentration of D-galactose of aging mice model.Methods:Kunming mice were randomly divided into 5 groups(5 mice in each group): control group, different doses of D- galactose groups(125mg / kg, 250 mg / kg, 500 mg / kg, 1000 mg / kg). Except the control group were subcutaneously injected with 0.3ml saline, the other groups were injected with the same volume but different concentrations of D-galactose, once daily for 8 week. Cell cycle distribution was detected by flow cytometry. Serum superoxide dismutase activity was detected.Results:The SOD activity of mice with different doses of D- galactose group was significantly lower than that in the control group, the difference was statistically significant(P<0.01 resp.); The SOD activity in 500mg/kg D-galactose group was significantly lower than that in 125mg/kg D-galactose, 250mg/kg D-galactose and 1000mg/kg D-galactose groups(P < 0.05 resp.). The number of cells arrested in G0/G1 phase in different doses of D-galactose groups was significantly higher than that in the control group, and the difference was statistically significant(P<0.01 resp.). The number of cells arrested in G0/G1 phase in 500mg/kg D-galactose group was significantly higher than that in 125mg/kg D-galactose, 250mg/kg D-galactose and 1000mg/kg D-galactose groups(P<0.05 resp.).Conclusions:The optimal concentration of D- galactose was 500mg/kg of the subacute aging mice model.Part two Anti-skin aging effect of total flavonoids from Inula Britannica on aging mouse model induced by D-galactoseObjective:Inula britannica flower is a well-known traditional Chinese herb, and its antioxidant activity is related with flavonoids1.The aim of this thesis is to explore the anti-aging effect of Inula britannica flower total flavonoids(IBFTF) on aging mice induced by D-galactose and its mechanism.Methods:In this study, mice were randomly divided into 6 groups(10 mice in each group): control group, model group, Vit E group, low, medium and high doses of IBFTF group. Except the control group were subcutaneously injected with 0.3 ml saline, the other groups were injected with the same volume of D-galactose(500mg/kg),once daily for 8 week.Followed by treatment with 0.5ml 100, 200 or 400mg/kg IBFTF, or a positive control(100mg/kg vitamin E) via intragastric administration once daily for 6 weeks from the third week. The control group and model group were orally administered equal volume of saline once daily for 6 weeks. Activity of antioxidant enzymes such as superoxide dismutase(SOD), malondialdehyde(MDA), catalase(CAT) and glutathione peroxidase(GSH-Px) were determined. And the skin histology index such as skin moisture, hydroxyproline(Hyp) content, collagen content and dermal thickness were detected; Cell cycle distribution was detected by flow cytometry; m RNA expression of senescence-associated target gene(Sirt1, p16, p21 and Cyclin D1) was detected by the RT-q PCR, and the expression of senescence-associated target protein was detected by western blot.Results:The activity of superoxide dismutase(SOD), catalase(CAT) and glutathione peroxidase(GSH-Px) in skin tissue of IBFTF groups was significantly higher than that in model group(P<0.05 resp.), and the content of malondialdehyde(MDA) was lower than that in model group(P<0.05 resp.). The skin moisture content of IBFTF groups was significantly higher than that of model group(P<0.01 resp.); The content of hydroxyproline(Hyp) in IBFTF groups was significantly higher than that in model group(P<0.05 resp.); The dermal thickness of IBFTF groups were significantly improved compared with that of the model group(P<0.01 resp.); The content of collagen fibers in skin tissue of IBFTF groups were significantly increased compared with that of the model group(P<0.01 resp.); The number of cells arrested in G0/G1 phase of IBFTF groups was significantly lower than that in model group(P<0.05 resp.); The m RNA and protein expression of Sirt1 and Cyclin D1 in skin tissue of IBFTF groups was significantly higher than that of the model group(P<0.05 resp.). While compared with model group, the m RNA expression of p16 and p21 in skin tissue of IBFTF groups was significantly lower(P<0.01 resp.), and the protein expression of p16 and p21 was significantly decreased(P<0.05 resp.).Conclusions:Our data indicates that IBFTF is a potential natural anti-skin-aging agent with great antioxidant ability in a Sirt1-dependent manner.