钙结合蛋白S100A8在扩张皮肤中的实验研究

Experimental study of calcium-binding protein S100A8 in expanded skin

目的探究扩张皮肤中钙结合蛋白S100A8的分布特征及其在皮肤扩张过程中的作用。方法构建大鼠头部皮肤扩张模型,利用免疫荧光染色、qPCR、Western blotting等方法检测皮肤中S100A8的分布及表达水平。随后,体外实验对人角质形成细胞拉伸,模拟扩张皮肤在机械应力下的状态,利用qPCR、酶联免疫吸附测定等实验检测细胞中及其上清液中S100A8的含量。应用S100A8重组蛋白或角质形成细胞拉伸后的上清液对人成纤维细胞增殖、迁移、胶原蛋白合成进行检测。结果大鼠扩张表皮层S100A8表达水平较高(P<0.01);角质形成细胞经体外拉伸后分泌大量S100A8(P<0.05,P<0.01);重组蛋白S100A8能促进成纤维细胞的增殖、迁移及胶原合成(P<0.05,P<0.01),并且角质形成细胞拉伸后的上清液也能促进成纤维细胞胶原合成(P<0.01)。结论机械应力能上调扩张表皮层中S100A8的表达,并通过旁分泌作用促进成纤维细胞增殖、迁移及胶原合成。

Objective To explore the distribution characteristics of calcium-binding protein S100A8 in expanded skin and its role during tissue expansion.Methods The head skin expansion model of rats was constructed,and the distribution and expression level of S100A8 in skin were detected by immunofluorescence staining,qPCR and Western blotting.Then,human keratinocytes were treated by in vitro stretching experiments to simulate the state of expanded skin under mechanical stress,and the content of S100A8 in cells and supernatants was detected by qPCR and enzyme-linked immunosorbent assay.S100A8 recombinant protein or supernatants of stretched keratinocytes were used to detect the proliferation,migration,and collagen synthesis of human fibroblasts.Results The expression level of S100A8 was significantly up-regulated in expanded epidermis of rats(P<0.01).S100A8 could be secreted greatly from stretched keratinocytes(P<0.05,P<0.01).S100A8 recombinant protein promoted the proliferation,migration and collagen synthesis of fibroblasts(P<0.05,P<0.01).In addition,supernatants of stretched keratinocytes also facilitated collagen synthesis of fibroblasts(P<0.01).Conclusion Mechanical stress can up-regulate the expression of S100A8 in expanded epidermis,and promote the proliferation,migration,and collagen synthesis of fibroblasts through paracrine effect.