Experimental Study On The Effects Of TET On Fibroblasts Isolated From Human Hypertrophic Scars

Objective To investigate the effects of TET on fibroblasts derived from human hypertrophic scar and explore its mechanisms in vitro so as to provide experimental data for prevention and treatment of hypertrophic scars with TET.Methods Fibroblasts primarily cultured were treated with a series of concentrations of TET(Triamcinolone was taken as positive control), Dm screened by MTT reduction assay then experimental groups designed according to this Dm. In formal experiments, MTT reduction assay, Flow cytometry after propidium iodide staining, improved chloraseptine T oxidizing assay, SDS-PAGE electrophoresis metrod and agarose gel electrophoresis were adopted to detect cellproliferation, cell cycle of fibroblasts and induction of fibroblasts'apoptosis as well as to measure the synthesis of collagen and activity of collagenase after TET treatment.Results ⑴ The cell proliferation was inhibited by TET. It showed thatdivision index and cell number during G0-G1 were decreased, while S and G2-M phases were lengthened with dosage and time dependency in dosages of TET from 2mg/L to 8mg/L; besides, oval-shap cells, karyopyknosis and fragmentation were observed under light microscope. The inhibitory effect in T2 group was statistically similar to that in triamcinolone.⑵ Contents of extracelluar collagen were diminished by TET also in a dosage and time dependent manner, but the effect of triamcinolone was less obvious than that of TET. ⑶ In the concentration below the lever of inhibiting fibroblasts'proliferation(<2mg/L/48h), the total activity of collagenase could be significantly increased by TET with dosage-dependence, while the enhancing effect of triamcinolone was much slighter than that of TET. ⑷ Apoptotic rate of fibroblasts induced by TET rised and apoptotic peak occurred with the increase of treated concentration, apoptotic rate up to 13.49%, and inducing effect in T2 group was a little stronger than that of triamcinolone. Besides, DNA "ladder" phenomenon was found in agarose gel electrophoresis of treatment and triamcinolone groups.Conclusion １The inhibiting effect of TET on proliferation and collagen's synthesis of fibroblasts in a dosage and time dependent manner was remanifested.2 Increasing activity of collagenase of degradation of collagen in adosage-dependent manner even in a lower concentration and Inducing apoptosis of fibroblasts in dosage-dependent manner were also the mechanisms of TET treating hypertrophic scar.3 Superiority of TET to triamcinolone was as follows:⑴ Influence of TET on scar fibroblasts was much stronger than that of triamcinolone, so the of effective dosage of TET could be lower than that of triamcinolone.⑵ Dosage and time dependence by the way TET affected most biological character of fibroblasts made it easy to clinical control.⑶ The dosage of TET coud be decreased, so the side-effect of hormone could be avoided.⑷ TET is the traditional Chinese medicine and it widespreads in many places, moreover it can be extracted easily with low cost price, which makes it easy to popularize in clinical use.