成骨细胞来源的IL-7通过激活mTORC1信号通路抑制骨形成  

Osteoblast-derived IL-7 Prohibits Bone Formation through Activating mTORC1 Signaling

作　　者：王华磊[1] 

机构地区：[1]南阳市中心医院骨外科,473000

出　　处：《医学研究杂志》2017年第12期157-160,共4页Journal of Medical Research

摘　　要：目的本研究探讨成骨细胞分泌的白介素-7(IL-7)通过哺乳动物雷帕霉素靶蛋白(mammalian target of rapamycin,m TOR)信号来调节骨形成。方法将IL-7基因的编码框构建于慢病毒表达载体,导入MC3 T3-E1成骨细胞中,应用q RT-PCR和ELISA方法检测IL-7基因m RNA和蛋白的表达效率。Western blot方法检测MC3 T3-E1细胞P-S6、S6、Ⅰ型胶原(collagenⅠ,ColⅠ)以及骨钙素(osteocalcin,Ocn)表达情况。用0.1nmol/L m TORC1特异性抑制剂雷帕霉素刺激过表达IL-7基因的MC3T3-E1成骨细胞,Western blot方法检测P-S6、S6、ColⅠ以及Ocn表达情况。结果过表达IL-7基因的慢病毒载体感染MC3T3-E1细胞可使其IL-7 m RNA表达上调4.6倍,ELISA从蛋白水平证实过表达组细胞上清的IL-7含量增加3.9倍;过表达IL-7的MC3T3-E1细胞P-S6蛋白表达显著增强,而ColⅠ和Ocn蛋白表达显著降低;雷帕霉素处理IL-7过表达的MC3T3-E1细胞导致其P-S6蛋白表达显著降低,而ColⅠ和Ocn蛋白表达上调。结论成骨细胞来源的IL-7通过促进m TORC1信号通路抑制其发育成熟。Objective To investigate the regulation of bone formation by osteoblast-derived interleukin-7 （IL-7） trough the mammalian target of rapamycin （mTOR） signaling pathway.Methods The lentiviral vector with encoding frame of IL-7 gene was transfected into mouse MC3T3-E1 osteoblasts, and the expression levels of IL-7 mRNA and protein were detected, respectively, by qRT-PCR and ELISA method. Western blot method was used to detect the expression levels of P-S6, S6, collagen Ⅰ （Col Ⅰ） and Osteocalcin （Ocn） in MC3T3-E1 cells and in MC3T3-E1 cells stimulated by 0.1nmol/L mTORC1-specific inhibitor rapamycin.Results The IL-7 mRNA level of MC3T3-E1 cells transfected with upregulated 4.6 times, and ELISA assay showed an increase of 3.9 times of IL-7 level in osteoblastic supernatants. After transfected using lentiviral vector with encoding frame of IL-7 gene, the expression levels of P-S6 protein increased significantly, while the expression levels of Col Ⅰ and Ocn protein decreased significantly. However, rapamycin treatment of over-expressed-IL-7 MC3T3-E1 cells resulted in a decline of P-S6 protein levels, but an increase of Col Ⅰ and Ocn protein levels.Conclusion Osteoblast-derived IL-7 may inhibit its maturation by promoting mTORC1 signaling pathway.

关 键 词：成骨细胞 白介素-7 MTOR 骨形成 

分 类 号：R34[医药卫生—基础医学]