咖啡因对肝星形细胞活性和分泌功能的影响

Effects of caffeine on viability and secretion of hepatic stellate cells

目的:研究咖啡因对肝星形细胞活化状态和分泌功能的影响及其潜在机制。方法:选取人肝星形细胞LX-2进行体外实验。经浓度为0、5、10、20、30、40 m M的咖啡因处理后,通过Western印迹法分别检测不同浓度的咖啡因对肝星形细胞中α-平滑肌肌动蛋白和凋亡蛋白cleaved-PARP表达量的影响;分别用CCK-8实验和流式细胞仪检测咖啡因对肝星形细胞活性和凋亡的影响。结果:在咖啡因作用下,肝星形细胞表达α平滑肌肌动蛋白的量与对照组相比显著减少,表示其分泌功能受到明显抑制。CCK-8实验表明咖啡因可抑制肝星形细胞的活性,并呈现时间和浓度依赖性。流式细胞技术显示咖啡因作用浓度增高,凋亡细胞的比例随之增高,同时,cleaved-PARP的表达量与对照组相比明显增多,提示咖啡因可诱导肝星形细胞凋亡。结论:咖啡因可通过诱导凋亡降低肝星形细胞的活性,减少肝星形细胞中α平滑肌肌动蛋白的表达量,从而抑制肝星形细胞分泌胶原纤维的功能。

Objective To investigate the effects of caffeine on viability and secretion of hepatic stellate cells（HSC）and the mechanisms.Methods Human HSC cell line LX-2 was used in in vitro study.LX-2 cells were incubated with caffeine at various concentrations（0,5,10,20,30 and 40 m M） and the expression of α-smooth muscle actin（α-SMA）and cleaved-PARP in HSC was detected by Western blot.The effect of caffeine on viability and apoptosis of LX-2 cell was analyzed by CCK-8 assay and flow cytometry respectively.Results Compared to control group,caffeine decreased the expression of α-SMA in LX-2 cell significantly indicating the secretion of HSC was inhibited.Caffeine was shown by CCK-8 assay to inhibit the viability of LX-2 cell in a dose-and time-dependent manner.It was indicated by flow cytometry that caffeine increased the number of apoptotic cells dose-dependently.Furthermore,it was also showed by Western blot the significant increase in the expression of cleaved-PARP of LX-2 cell compared with control group,suggesting caffeine could induce the apoptosis of LX-2 cell.Conclusions The results demonstrate that caffeine inhibits the viability of HSC via inducing apoptosis of HSC and reduces the expression of α-SMA in HSC,which inhibits the secretion of collagen fiber in HSC.