脂联素通过激活p38MAPK信号通路调节大鼠肝星状细胞MMP-13及TIMP-1表达

目的观察外源性脂联素对体外培养的大鼠肝星状细胞系(HSC-T6)细胞脂联素受体1(AdipoR1)表达的调节作用及对细胞内p38MAPK信号通路的影响,并观察该通路是否参与调节脂联素对HSC细胞基质金属蛋白酶-13(MMP-13)、基质金属蛋白酶抑制因子-1(TIMP-1)表达的影响。方法 MTT法观察不同浓度脂联素对HSC生长的影响。荧光定量PCR法检测脂联素作用下HSC-T6细胞AdipoR1、MMP-13、TIMP-1的mRNA表达情况。Western blotting方法检测脂联素作用下HSC-T6细胞信号蛋白p38MAPK的活化及活性和AdipoR1、MMP-13、TIMP-1的蛋白表达情况。结果 0.5μg/mL～2.0μg/mL脂联素处理HSC细胞,各组细胞增生无明显变化。0.5μg/mL、1.0μg/mL、1.5μg/mL脂联素作用下AdipoR1mRNA和蛋白表达增加。1.0μg/mL脂联素处理HSC后,p38MAPK激酶磷酸化水平随时间增加而增高,在120min达最大值,之后又开始下降。不同浓度脂联素处理HSC120min后,p38MAPK激酶磷酸化水平均增加,并具有浓度依赖性。p38MAPK抑制剂SB203580可抑制p38MAPK激酶的磷酸化及活性。脂联素处理组HSC细胞MMP-13mRNA及蛋白表达均较对照组明显增加,而TIMP-1mRNA及蛋白表达较对照组降低,而SB203580可以抑制这种效应。结论脂联素可上调活化肝星状细胞AdipoR1的表达,通过激活p38MAPK信号通路,调节HSC细胞MMP-13及TIMP-1的表达。

Adiponectin Modulates MMP-13 and TIMP-1 Expression via p38MAPK Pathway in Rat Hepatic Stellate Cell Line

Objective To investigate the effects of adiponectin on adiponectin receptor 1(AdipoR1) gene and protein expression in hepatic stellate cells(HSCs), and to evaluated the changes of p38MAPK pathway and its influence on matrix metalloproteinase-13(MMP-13) and tissue inhibitor of metalloproteinase-1(TIMP-1） expression in HSCs on the treatment of adiponectin. Methods HSCs proliferation was detected by MTT assay. AdipoR1, MMP-13 and TIMP-1 mRNA levels were detected by real-time RT-PCR. Western blotting was used to detect AdipoR1, MMP-13, TIMP-1, phospho-p38MAPK and phospho-pATF-2 protein expressions in HSCs. Results Adiponectin at concentrations 0.5 μg/mL-2.0 μg/mL had no effect on HSCs proliferation, however, AdipoR1 gene and protein expressions was up-regulated in adiponectin groups compared with control group. Adiponectin could increase phospho-p38MAPK protein expressions in dose and time dependent manners and had a maximal effect after 120 min treatment with adiponectin. Compared with control group, adiponectin could significantly increase MMP-13 gene and protein expressions, moreover, the blocker of p38MAPK could inhibit this effect of adiponectin in HSCs. The mRNA and protein level of TIMP-1 was decreased on the treatment with adiponectin, and this effect of adiponectin could be inhibited by p38MAPK's blocker. Conclusion Adiponectin could up-regulate AdipoR1 expression in HSCs. MMP-13 and TIMP-1 expressions in HSCs could be regulated by adiponectin through activation of p38MAPK pathway.