miR-214通过对BMP-2和Smad4的靶向调控作用对骨质疏松的影响

目的探究miR-214能否靶向调控BMP-2和Smad4对骨质疏松症产生影响。方法将大鼠分为2组(假手术组、手术组),对手术组进行手术构建去卵巢骨质疏松模型,对两组大鼠血清中相关因子、骨密度、股骨进行病理学染色观察,同时将各组大鼠骨髓间充质干细胞(BMSCs)进行体外培养,使用q PCR检测其miR-214表达水平,Western blot检测其BMP-2和Smad4相关蛋白表达水平。体外培养大鼠成骨细胞,将细胞分为3组(对照组、过表达组和抑制组),向过表达组和抑制组分别转染miR-214 mimics及anti-miR-214,对各组大鼠成骨细胞的增殖能力、细胞凋亡情况和BMP-2和Smad4相关蛋白表达水平进行检测。结果与假手术组相比,手术组大鼠血钙、碱性磷酸酶(ALP)水平及骨密度(BMD)明显下降,血磷水平明显上升,差异具有统计学意义(P0.05)。两组大鼠的BMSCs增长速率相比差异无统计学意义(P0.05),同时假手术组大鼠BMSCs ALP水平显著高于手术组,差异具有统计学意义(P0.05)。手术组与假手术组的BMSCs相比较,细胞中miR-214表达明显上升,BMP-2及Smad4表达水平明显下降,差异具有统计学意义(P0.05)。对转染后各组大鼠成骨细胞检测,与对照组相比,过表达组细胞增殖能力明显下降,细胞凋亡情况显著增高,BMP-2及Smad4水平下降,抑制组细胞增殖能力显著升高,细胞凋亡数量明显下调,BMP-2及Smad4表达水平升高,差异具有统计学意义(P0.05)。结论 miR-214可能通过靶向调控BMP-2与Smad4抑制成骨细胞的增殖,从而发生或发展成骨质疏松症。

Effects of miR-214 on osteoporosis through targeted regulation of BMP-2 and Smad4

Objective To investigate whether miR-214 can regulate BMP-2 and Smad4 in osteoporosis. Methods The Rats were divided into two groups (control group, surgery group), the surgery treatment of osteoporosis rats model was established, and the related factor in serum of two groups of rats, bone density, femur dyeing for pathology observation, at the same time each group of rat bone marrow mesenchymal stem cells (BMSCs) were cultured in vitro, and the expression levels of miR-214 were detected by qPCR, and the expression levels of BMP-2 and Smad4 related proteins were detected by Western blot.Rat osteoblasts were cultured in vitro and divided into 3 groups (control group, overexpressed group and inhibited group). miR-214 mimics and anti-miR-214 were transfected into the overexpressed group and the inhibited group, respectively. The proliferation ability, apoptosis, and expression levels of BMP-2 and smad4-related proteins in rat osteoblasts in each group were tested. Results Compared with the sham group, serum calcium, alkaline phosphatase (ALP) concentration and bone mineral density (BMD) of the rats in the operation group were significantly decreased, and serum phosphorus content was significantly increased, with statistically significant differences(P<0.05).Meanwhile, the BMSCs ALP content in the sham group was significantly higher than that in the operation group. Compared with the BMSCs of the surgery group and the sham surgery group, the expression of mirR-214 in the cells was significantly increased, with statistically significant differences (P<0.05).Detection of each rat osteoblast after transfection, compared with control group, the expression group cell proliferation capacity decreased obviously, cell apoptosis was significantly increased, BMP-2 and Smad4 expression levels, and inhibiting group increased cell proliferation, apoptosis, a significant reduction in BMP-2 and Smad4 expression levels, statistically significant difference (P<0.05).Conclusion miR-214 may inhibit the proliferation of osteoblasts by targeting BMP-2 and Smad4, leading to the occurrence or development of osteoporosis.