Inhibitory Effect Of Diosgenin On Proliferative Scar In Vivo And In

Purpose: We investigated the effect of dioscin on hypertrophic scar of rabbit ear in vivo and on treating human hypertrophic scar fibroblast(hHSF) in vitro and tried to elucidate the possible mechanisms.Material and method:First, rabbit ear hypertrophic scars model was created, and 6New Zealand white rabbits were randomly divided into two groups. The ears were caused8 mm diameter circular abdominal wound, establishing animal model of hypertrophic scars.Scar formation was observed daily. After 15 days later, the rabbits were given dioscin, the experimental group dose of 5mg/kg, while the control group was given equal normal saline.The number of doses to be administered once a day for consecutive 20 days, and the preparation of samples was drawn at 21 days. H & E staining was used to investigate rabbit’s scar tissue scar index and arrangement of the collagen. Cell viability was determined by MTT assay after treatment with dioscin for 24 h, 48 h and 72 h. Number of viable cell was determined by Trypan blue assay after treatment with dioscin for 12 h and 24 h.Cellular migration abilities were assayed by scratch test. Apoptosis were determined by Annexin V-FITC/PI assay after treatment with dioscin for 24 h. Western blot analysis was performed to study the expression of TGF-β1, caspase3, caspase9, BAX, Bcl-2 and collagen I.Real time RT-PCR was performed to detect the change in TGF-β1 mRNA expression.Results:1. Dioscin markedly improved hypertrophic scars of rabbit ear. Scar index(1.832±0.413) in experiment group was lower than it(2.756±0.405) in control group.2. Dioscin remarkably suppressed hHSF cell proliferation(IC50 of 24 h = 5.6±0.7μg/ml, IC50 of 48h = 2.4±0.3μg/ml, IC50 of 72 h = 1.3±0.2μg/ml).3. Dioscin significantly inhibited cellular migration abilities of hHSF.4. Dioscin increased expressions of BAX, caspase9 and caspase3 and decreased Bcl-2expression leading to increased apoptosis of hHSF.5. Dioscin decreased the expression of TGF-β1 and collagen I in hHSF.Conclusion:1. Dioscin has a good therapeutic effect on hypertrophic scars of rabbit ear.2. Dioscin increased apoptosis of hHSF by Bax/Bcl-2 pathway.3. Dioscin suppressed hHSF proliferation and cellular migration abilities by suppressing TGF-β1 expression.4. Dioscin decreased the expression of TGF-β1 and collagen I to inhibit hypertrophic scar.