目的:文献表明,并非所有绝经后妇女都患有骨质疏松症,绝经后骨质疏松症的发生与人群基因的遗传易感性及相关基因的细胞通路密切相关。系统了解SCIMP基因在骨质疏松中的作用,在这项综合研究中,对体外和体内实验进行了深入分析。
方法:从GEO数据库中选择绝经后骨质疏松症(PMOP)患者的显着差异表达基因。同时,还使用ELISA方法在临床招募的个体中确认了主要靶基因;随机招募了50例T评分为-2.5的绝经后骨质疏松症患者;将T评分>-2.5的绝经后女性纳入非骨质疏松组(包括骨质减少和骨矿物质密度正常).通过GO和KEGG富集分析对相关过程和信号通路进行了深入研究。下游信号因素包括Erk-1/2、Akt、使用MG-63细胞系评估潜在基因的IkB相关信号通路;MTT,CCK-8和流式细胞术检测MG-63细胞活力,扩散,以及细胞凋亡,分别,在不同的待遇下。
结果:基于GEO数据库的差异表达基因分析,PMOP患者显示845个差异表达基因,包括709个下调和136个上调。包括SCIMP的10个基因显著差异表达(至少3倍差异)。在PMOP患者标本中,SCIMP下降最明显。使用临床招募的个体,PMOP组的SCIMP浓度为96.6±20.8ng/μL,对照组为168.8±23.5ng/μL(p<0.05)。同时,根据KEGG分析,破骨细胞分化信号通路显著上调,而刺猬及其他信号通路下调.在si-SCIMP处理中Akt的磷酸化水平被显著阻断。SCIMP的上调增加了细胞增殖,抑制细胞凋亡,增强MG-63细胞的细胞活力,AKT磷酸化抑制剂显着挽救。最后,体内实验还证实,SCIMP的上调增强了大鼠骨小梁的结构参数和骨组织的成骨活性。
结论:SCIMP在女性绝经后骨质疏松的发病机制中起关键作用。SCIMP通过akt依赖性分子途径影响破骨细胞功能,进而影响骨代谢的平衡过程。这为绝经后骨质疏松症的发病机制及临床治疗提供了新的思路。
OBJECTIVE: The literature suggests that not all postmenopausal women suffer from osteoporosis, and the occurrence of postmenopausal osteoporosis is closely related to the genetic susceptibility of genes in the population and the cellular pathways of related genes. To systematically understand the functions of
SCIMP gene for osteoporosis, both in vitro and in vivo experiments were analyzed in depth in this integrated study.
METHODS: The significantly differentially expressed genes of postmenopausal osteoporosis (PMOP) patients from GEO database were selected. Meanwhile, the primary target gene was also confirmed in clinically recruited individuals using ELISA method; 50 postmenopausal osteoporosis patients with a T-score of -2.5 were randomly enrolled; postmenopausal women with a T-score > -2.5 were included in the non-osteoporotic group (including osteopenia and normal bone mineral density). The associated processes and signaling pathways were deeply investigated with GO and KEGG enrichment analysis. The downstream signaling factors including Erk-1/2, Akt, and IkB-related signaling pathways for the potential gene were evaluated using MG-63 cell line; the MTT, CCK-8, and flow cytometry assays were performed to exam MG-63 cell viability, proliferation, as well as apoptosis, respectively, under different treatments.
RESULTS: Based on the differentially expressed gene analysis for GEO database, PMOP patients displayed 845 differentially expressed genes, including 709 down-regulated and 136 up-regulated ones. Ten genes including
SCIMP were significantly differentially expressed (at least three-fold difference).
SCIMP was the most markedly decreased in PMOP patients\' specimens. Using clinical recruited individuals, the concentration of SCIMP was 96.6 ± 20.8 ng/μL in the PMOP group compared with 168.8 ± 23.5 ng/μL in the control group (p < 0.05). At the same time, the osteoclast differentiation signaling pathway was significantly up-regulated while hedgehogs as well as other signaling pathways were down-regulated based on the KEGG analysis. The phosphorylation level of Akt was markedly blocked in si-
SCIMP treatment. Up-regulation of SCIMP increased cell proliferation, inhibited cell apoptosis, and enhanced cell viability in MG-63 cells, which was markedly rescued by AKT phosphorylation inhibitor. Finally, in vivo experiments also confirmed that the upregulation of SCIMP enhanced the structural parameters of rat trabecular bone and the osteogenic activity of bone tissue.
CONCLUSIONS: SCIMP plays a critical role in the pathogenesis of postmenopausal osteoporosis in women. SCIMP influences osteoclasts function through an akt-dependent molecular pathway, and subsequently influences the equilibrium process of bone metabolism. This provides a new insight into the pathogenesis of postmenopausal osteoporosis as well as the clinical treatment of osteoporosis.