人脐带间质干细胞培养上清液可下调肝星状细胞转化生长因子β的表达

背景：人脐带间质干细胞有望成为治疗肝纤维化新的种子细胞,但目前相关的体外实验报道较少。目的：探讨人脐带间质干细胞培养液上清对大鼠肝星状细胞纤维化形成生物学活性的影响及可能的作用靶点。方法：将肝星状细胞以1.0×108L-1接种于六孔板内,无血清培养24h后,加入2mL脐带间质干细胞培养液上清处理肝星状细胞,设为实验组;对照组为加入等量完全培养基处理肝星状细胞;RT-PCR法检测肝星状细胞内转化生长因子β1、collagen-α1、TIMP-2 mRNA表达;Western blot法检测肝星状细胞内转化生长因子β1蛋白表达。结果与结论：实验组中肝星状细胞内转化生长因子β1、collagen-α1、TIMP-2 mRNA表达较对照组明显下调,且随处理时间的延长,mRNA表达的下调程度亦随之增强（实验组72h〉实验组48h〉对照组）;实验组肝星状细胞内转化生长因子β1蛋白表达较对照组下调,同时具有时间依赖性（对照组〉实验组48h〉实验组72h,P〈0.05）。提示脐带间质干细胞可抑制肝星状细胞纤维化形成的生物学活性,并可能是通过针对转化生长因子β靶点及其下游基因产物起作用。

Human umbilical cord stromal stem cells-conditioned medium down-regulated the expression of transforming growth factor beta in rat hepatic stellate cells

BACKGROUND：Human umbilical cord stromal stem cells are expected to become a new seed cell in the treatment of live cirrhosis.However,few studies of in vitro experiment have been reported.OBJECTIVE：To explore the effect of human umbilical cord stromal stem cells-conditioned medium（USSC-CM） on the biological activity of fibrosis in rat hepatic stellate cells（HSCs）,and the acting target.METHODS：HSCs were seeded in the six orifice plate in proportion（1.0×105 /mL）,then cultured without serum for 24 hours;2 mL USSC-CM were added to treat HSCs as experimental group;while HSCs were treated with equivalent fresh medium as control group.The expression of transforming growth factor β1（TGF-β1）,collagen-α1 and TIMP-2 mRNA in HSCs were detected by RT-PCR.The expression of TGF-β1 protein was determined by Western blot.RESULTS AND CONCLUTION：The expression of TGF-β1,collagen-α1 and TIMP-2 mRNA in HSCs were down-regulated in experimental group compared to control group,and the tendency enhanced with time（USSC-CM treated 72 h USSC-CM treated 48 h control group）.And the expression of TGFβ1 protein in HSCs were down-regulated in experimental group compared to control group and showed time dependent manner（control group USSC-CM treated 48 h group USSC-CM treated 72 h group,P 0.05）.Human umbilical cord stromal stem cells can inhibit biological activity of HSCs.And it may carry its point by focusing on the acting target related to TGF-β together with downstream production.