MAPK-ERK1/2信号通路调控成骨性基因表达和细胞增殖  

MAPK-ERK1/2 signaling pathway regulates osteogenic gene expression in rat osteoblasts in vitro

作　　者：丁道芳[1,2] 李玲慧[1,2] 宋奕[1,2] 杜国庆[1,2] 卫晓恩[1,2] 曹月龙[1,2] 

机构地区：[1]上海中医药大学附属曙光医院石氏伤科医学中心 [2]上海市中医药研究院骨伤科研究所,上海201203

出　　处：《南方医科大学学报》2013年第10期1432-1436,共5页Journal of Southern Medical University

基　　金：国家自然科学基金(81073114;81072830);上海市教育委员会创新项目(11YZ64);上海市高校青年教师培养资助计划(ZZszy12017)~~

摘　　要：目的观察在不同浓度大鼠血清作用下,激活或抑制MAPK-ERK1/2信号通路对大鼠成骨细胞的成骨性基因表达和增殖的影响。方法原代培养大鼠成骨细胞,进行形态和碱性磷酸酶初步鉴定后,分别用1%和5%的大鼠血清进行培养24 h,WB检测MAPK-ERK1/2信号通路蛋白p-ERK1/2和ERK1/2表达,同时检测成骨性基因(Runx2、Ⅰ型胶原和碱性磷酸酶)和增殖蛋白PCNA的表达;MAPK-ERK1/2信号通路阻断剂PD0325901抑制P-ERK1/2的表达后观察对Runx2、Ⅰ型胶原和碱性磷酸酶和增殖蛋白PCNA的表达。结果 5%大鼠血清激活p-ERK1/2水平明显高于1%大鼠血清(P<0.05),在MAPK-ERK1/2高水平激活状态下,成骨性基因如Runx2、Ⅰ型胶原和碱性磷酸酶的表达水平出现显著的增加及促进PCNA的表达;当抑制MAPK-ERK1/2信号通路时,成骨性基因Runx2、Ⅰ型胶原和碱性磷酸酶的表达水平也随之下调,且PCNA表达也受到抑制。结论激活MAPKERK1/2通路促进成骨基因表达和成骨细胞增殖,抑制此通路将抑制成骨性基因表达和细胞增殖,此通路可能作为治疗骨质疏松症的药物靶点。Objective To investigate the effect of inhibition and activation of MAPK-ERK1/2 pathway on the expression of osteogenic genes and proliferation of rat osteoblasts in vitro. Methods Primarily cultured rat osteoblasts, identified by cell morphology studies and ALP staining, were exposed to 1% or 5% rat serum for 24 h or to the specific MAPK-ERK1/2 inhibitor PD0325901. The downstream molecules of MAPK-ERK1/2 pathway including p-ERK1/2 and ERK1/2, osteogenic genes such as Runx2 and Type I collagen, and proliferating cell nuclear antigen （PCNA） were detected by Western Blotting, and alkaline phosphatase activities were analyzed quantitatively. Results Compared with 1% rat serum-treated ceils, exposure of the cells to a higher concentration （5%） of rat serum caused a significantly increased phosphorylation level of p-ERK1/2 （P〈0.05） and obviously enhanced expressions of the osteogenic genes （Runx2, type I collagen and ALP） and PCNA （P〈0.05）. Inhibition of the MAPK-ERK1/2 pathway with PD0325901 resulted in suppressed expressions of the osteogenic genes and PCNA. Conclusion The activation of MAPK-ERK1/2 pathway promotes the expression of osteogenic genes such as Runx2, type I collagen and ALP and enhances the proliferative activity of the osteoblasts, while inhibition of this pathway suppresses the expressions of these genes and the cell proliferation, suggesting that this pathway may potentially serve as a therapeutic target for osteoporosis.

关 键 词：原代成骨细胞 成骨性基因表达 大鼠血清 信号通路 

分 类 号：R363[医药卫生—病理学]