随机回转模拟失重对成骨细胞MACF1表达和β-catenin信号通路的影响

Effects of Simulated Weightlessness with Random Positioning Machine on Microtubule Actin Crosslinking Factor 1 Expression and β-catenin Pathway in Osteoblast

目的研究随机回转(RPM)模拟失重条件对微管微丝交联因子1(MACF1)表达及β-catenin信号通路的影响,为失重性骨丢失机制研究提供实验依据。方法 RPM条件培养成骨细胞,PCR检测MACF1mRNA表达变化,Western blot检测MACF1以及不同磷酸化位点β-catenin蛋白表达变化,荧光素酶报告基因检测细胞β-catenin荧光素酶活性变化。结果 RPM模拟失重条件下,成骨细胞MACF1表达下降,β-catenin mRNA和不同位点磷酸化蛋白表达量发生改变;MACF1 shRNA抑制了成骨细胞中β-catenin表达,影响了β-catenin蛋白稳定性及活性。结论 RPM模拟失重抑制了MACF1表达和β-catenin表达及活性;MACF1 shRNA影响了β-catenin表达及活性。MACF1可能是一种力敏感分子,通过调控β-catenin参与成骨细胞对力学信号的感知和响应。

Objective To investigate the effects of simulated weightlessness with random positioning machine（ RPM） on microtubule actin crosslinking factor 1（ MACF1） expression and β-catenin signal pathway in osteoblast to provide some evidence for studying the mechanism of bone loss induced by microgravity. Methods After the osteoblasts were cultured in RPM condition for 48 h,PCR and western blot were used to detect the MACF1 and β-catenin expression. Phosphorylated β-catenin expression was also detected with western blot assay. Luciferase activity of β-catenin was examined by report gene detection assay. Results Simulated weightlessness with RPM inhibited MACF1 expression,and affected β-catenin mRNA expression,phosphorylated β-catenin expression and activity in osteoblasts. MACF1 shRNA inhibited β-catenin expression,stability and activity in osteoblasts. Conclusion RPM simulated weightlessness inhibits MACF1 expression,and β-catenin expression and activity. MACF1 shRNA affects β-catenin expression and activity in osteoblasts. It suggests that MACF1 may be sensitive to mechanical stimulus and involved in osteoblast sensing and responding to mechanical stimulus via regulating β-catenin expression and activity.