过表达miR-664a-5p激活Wnt/β-catenin信号通路促进骨质疏松大鼠骨重建

Overexpression of miR-664a-5p activates Wnt/β-Catenin signaling pathway promotes bone remodeling in osteoporosis rats

目的探究过表达miR-664a-5p的脂肪间充质干细胞(miR-664a-5p-ADSCs)通过激活Wnt/β-catenin信号通路对骨质疏松(OP)大鼠骨重建的促进作用。方法将大鼠分为Sham组、OVX组、ADSCs组和miR-664a-5p-ADSCs组。切除卵巢建立OP大鼠模型,Sham组仅切除脂肪组织。3个月后,ADSCs组和miR-664a-5p-ADSCs组分别尾静脉注射miR-664a-5p-ADSCs及其阴性对照ADSCs;Sham组和OVX组注射等量生理盐水。1个月后进行指标检测。micro-CT、HE染色、TRAP染色检测OP大鼠骨重建情况;免疫组化染色、RT-qPCR、Western blot检测Runx2、ALP、OCN、Wnt、β-catenin mRNA和蛋白的表达。结果Sham组骨小梁完整,破骨细胞较少;与Sham组相比,OVX组骨小梁稀疏且变薄,破骨细胞较多;Runx2、ALP、OCN、Wnt、β-catenin mRNA和蛋白水平明显降低(P<0.05);与OVX组相比,ADSCs组、miR-664a-5p-ADSCs组骨小梁增加且增厚,破骨细胞较少;Runx2、ALP、OCN、Wnt、β-catenin mRNA和蛋白水平明显升高,且miR-664a-5p-ADSCs组上述效果强于ADSCs组(P<0.05)。结论过表达miR-664a-5p的ADSCs通过激活Wnt/β-catenin信号通路促进OP大鼠骨重建。

Objective To explore the promoting effect of overexpression of miR-664a-5p in ADSCs(miR-664a-5p-ADSCs)on bone remodeling in osteoporosis(OP)rats via activating Wnt/β-catenin signal pathway.Methods Rats were divided into Sham group,OVX group,ADSCs group,and miR-664a-5p-ADSCs group.OP rat model was established by ovariectomy.Adipose tissue was removed only in Sham group.After 3 months,rats in the ADSCs group and the miR-664a-5p-ADSCs group were injected with ADSCs or miR-664a-5p-ADSCs through tail vein,respectively.Rats in Sham group and OVX group were injected with the same amount of normal saline.Index detection was performed after 1 month.Micro-CT,HE staining,and TRAP staining were used to detect bone remodeling in OP rats.Immunohistochemical staining,RT-qPCR,and Western blotting were used to detect the expressions of Runx2,ALP,OCN,Wnt,andβ-Catenin mRNA and protein.Results In Sham group,the bone trabeculae were complete and osteoclasts were few.Compared with that in Sham group,the bone trabeculae in OVX group were sparse and thin,and there were more osteoclasts.The levels of Runx2,ALP,OCN,Wnt,andβ-Catenin mRNA and protein decreased significantly(P<0.05).Compared with those in OVX group,bone trabeculae in ADSCs group and miR-664a-5p-ADSCs group increased and thickened,and osteoclasts were less.The levels of Runx2,ALP,OCN,Wnt,andβ-Catenin mRNA and protein increased significantly(P<0.05).The above effects in miR-664a-5p-ADSCs group were stronger than those in ADSCs group(P<0.05).Conclusion Overexpression of miR-664a-5p in ADSCs promotes bone remodeling in OP rats via activating Wnt/β-catenin signal pathway.