新橙皮苷治疗骨质疏松症的靶点及对骨髓间充质干细胞成骨分化的作用

Target of neohesperidin in treatment of osteoporosis and its effect on osteogenic differentiation of bone marrow mesenchymal stem cells

背景:前期研究发现新橙皮苷可以延缓去卵巢小鼠的骨丢失,具有治疗骨质疏松症的潜力,但其具体作用机制仍有待探究。目的:基于生物信息学和体外细胞实验探索新橙皮苷治疗骨质疏松症的关键靶点与可能机制。方法:从GEO数据库获得骨质疏松症相关的基因表达数据集,通过R语言筛选和分析差异表达基因,从GeneCards和DisGeNET数据库筛选骨质疏松症的相关靶点,从ChEMBL和PubChem数据库筛选新橙皮苷的相关靶点,三者取交集获得共同靶点,使用String数据库构建交集基因的PPI网络,筛选关键目标靶点,使用DAVID数据库进行GO、KEGG富集分析,运用AutoDock软件对新橙皮苷与目标靶点蛋白进行分子对接验证。检测新橙皮苷对C57小鼠骨髓间充质干细胞成骨分化的影响,以完全培养基为空白对照组、成骨诱导液为对照组,含不同浓度(25,50μmol/L)新橙皮苷的成骨诱导液为实验组,在相应时间检测细胞成骨分化过程中碱性磷酸酶的表达、矿化程度、成骨相关基因及目标靶点基因的表达。结果与结论:(1)筛选出差异表达基因9253个,骨质疏松症相关靶点2161个,新橙皮苷相关靶点326个,三者共同靶点53个,53个基因在骨质疏松症样本中皆上调。PPI网络筛选出具有研究意义的目标靶点基因PRKACA。GO功能与KEGG通路富集分析表明,新橙皮苷通过PRKACA靶点治疗骨质疏松症主要依靠蛋白质磷酸化和蛋白质自身磷酸化等生物过程,作用于内分泌抵抗、癌症中的蛋白聚糖、雌激素信号通路等发挥治疗作用。分子对接结果表明,新橙皮苷与目标靶点PRKACA对应的蛋白有一定的结合能力。(2)碱性磷酸酶染色显示新橙皮苷可以促进间充质干细胞成骨分化早期碱性磷酸酶的表达,茜素红染色显示新橙皮苷可以促进间充质干细胞成骨分化的矿化。RT-qPCR检测结果显示,新橙皮苷可以促进碱性磷酸酶、PRKACA、骨钙素mRNA的表达。(3)结果表明,新橙皮苷可能通过雌激素信号通路上的PRKACA靶点促进成骨分化,从而防治骨质疏松症。

BACKGROUND:Previous studies have found that neohesperidin can delay bone loss in ovariectomized mice and has the potential to treat osteoporosis,but its specific mechanism of action remains to be explored.OBJECTIVE:To explore the key targets and possible mechanisms of neohesperidin in the treatment of osteoporosis based on bioinformatics and cell experiments in vitro.METHODS:The gene expression dataset related to osteoporosis was obtained from GEO database,and the differentially expressed genes were screened and analyzed in R language.The osteoporosis-related targets were screened from GeneCards and DisGeNET databases,and the neohesperidin-related targets were screened from ChEMBL and PubChem databases,and the common targets were obtained by intersection of the three.The String database was used to construct the PPI network of intersection genes,and the key targets were screened.The DAVID database was used for GO and KEGG enrichment analysis.The AutoDock software was used to verify the molecular docking between the neohesperidin and the target protein.The effect of neohesperidin on osteogenic differentiation of C57 mouse bone marrow mesenchymal stem cells was detected.Complete medium was used as blank control group;osteogenic induction medium was used as the control group;and osteogenic induction medium containing different concentrations of neohesperidin(25,50μmol/L)was used as experimental group.The expression of alkaline phosphatase,the degree of mineralization,the expression of osteogenic-related genes and target genes during osteogenic differentiation of cells were measured at corresponding time points.RESULTS AND CONCLUSION:(1)9253 differentially expressed genes,2161 osteoporosis-related targets,and 326 neohesperidin-related targets were screened.There were 53 common targets among the three.All 53 genes were up-regulated in osteoporosis samples.The PPI network screened the target gene PRKACA of research significance.GO function and KEGG pathway enrichment analysis showed that neohesperidin's treatment of osteoporosis through PRKACA target mainly depended on biological processes such as protein phosphorylation and protein autophosphorylation,acting on endocrine resistance,proteoglycan in cancer,and estrogen signaling pathway to play a therapeutic role.Molecular docking results showed that neohesperidin had a certain binding ability to the protein corresponding to the target PRKACA.(2)The results of alkaline phosphatase staining showed that neohesperidin could promote the expression of alkaline phosphatase in the early stage of osteogenic differentiation of mesenchymal stem cells.Alizarin red staining showed that neohesperidin could promote the mineralization of osteogenic differentiation of mesenchymal stem cells.RT-qPCR results showed that neohesperidin could increase the mRNA expression of alkaline phosphatase,PRKACA,and osteocalcin.(3)These results indicate that neohesperidin may promote osteogenic differentiation through PRKACA target on the estrogen signaling pathway to prevent and treat osteoporosis.