辛伐他汀促进大鼠骨髓基质细胞的成骨分化

Stimulation on osteoblastic differentiation in bone marrow stromal cells of rats by simvastatin administration

目的观察辛伐他汀体内给药对去卵巢大鼠骨髓基质细胞(BMSC)增殖和分化的影响,探讨辛伐他汀的成骨作用机制。方法24只12周龄雌性SD大鼠随机分成4组,每组6只:假手术组(G1)和去卵巢组(G2)每天蒸馏水灌胃;去卵巢大鼠10mg·kg-1·d-1辛伐他汀灌胃(G3);去卵巢大鼠20mg·kg-1·d-1辛伐他汀灌胃(G4)。实验持续4周,第29天处死所有大鼠取骨髓细胞培养。用CellCountingKit8(CCK8)法检测成骨细胞的增殖能力;细胞培养第14天用半定量RTPCR和westernblot检测Runx2CbfalmRNA和蛋白的表达、第16天检测碱性磷酸酶活性(ALP)和第21天检测茜素红染色。结果辛伐他汀不能促进去卵巢大鼠成骨细胞增殖。G3组和G4组的Runx2Cbfa1mRNA表达水平和ALP活性都显著高于G2组,给药两组之间无显著差别。G4组的Runx2Cbfal蛋白表达水平比G2组和G3组显著增加,G2组与G3组无明显差别。茜素红染色表明辛伐他汀能促进成骨细胞的矿化能力,两种剂量组之间无明显差别。结论辛伐他汀体内给药能够促进去卵巢大鼠BMSC向成骨细胞分化,但是不能促进细胞增殖。

Objective To investigate the effects of simvastatin on proliferation and differentiation of the cultured bone marrow stromal cells （BMSC） in ovariectiomized （OVX） rats, and to study the mechanism of bone formation stimulative effect by simvastatin administraiton. Methods Twenty-four 12-week-old female Sprague-Dawley rats were randomized into four groups of six animals in each ： sham operated rats （ GI ） and OVX rats （（32） were administered with distilled water vehicle by garage daily;OVX rats （G3） were administered with 10mg·kg^-1·d^-1 of simvastatin by garage; OVX rats （G4） were administered with 20 mg·kg^-1·d^-1 of simvastatin by garage. The experiment lasted for four weeks, and all animals were sacrificed on the 29^th day. BMSC were collected and planted at plate. Cell Counting Kit-8（CCK-8）was used to determine the osteoblastic proliferation. The expression of mRNA and protein of Runx 2/Cbfal were detected by semi-quantiative RT-PCR and Western Blot on the 14^th days of culture Alkaline phosphatase （ALP） activity and Alizarin Red-S staining were perfermed on day of 16 and 21. Results Simvastatin did not stimulate the osteoblastic proliferation in OVX rats. The expression of Runx 2/Cbfal mRNA and ALP activity in G3 and G4 were enhanced significantly compared to （32, but no significant difference was found between G3 and G4.The expression of Runx 2/Cbfal protein in G4 increased significantly in comparison to （32 and G3, but no significant difference was found between （32 and G3. Alizarin Red-S staining showed that simvastatin stimulated osteoblastic mineralization significantly, but no significant difference was found between G3 and G4. Conclusions Simvastatin is able to stimulate osteoblastic differentiation in BMSC, but not proliferation.