吡格列酮对大鼠骨髓间充质干细胞向成骨细胞分化的影响

Effects of pioglitazone on BMSCs differentiation into osteoblastic lineages

目的体外观察葡萄糖与吡格列酮(PIO)对骨髓间充质干细胞(BMSCs)向成骨细胞(OB)分化的影响,探讨二者对骨代谢的作用机制。方法从大鼠长骨骨髓分离获取间充质干细胞,在不同糖浓度(5.6、25、50mmol.L-1)与PIO(0.1μg.mL-1)干预下向成骨细胞诱导分化培养21d;茜素红染色、光镜计数矿化率;realtime PCR测定OB的标记物碱性磷酸酶(ALP),骨钙素(BGP)及转录因子Runx2 mRNA表达,进行不同糖浓度组间及PIO干预后的变化比较。结果随糖浓度升高,矿化率显著降低,与对照组(5.6mmol.L-1)相比,25mmol.L-1糖浓度组降低了21%,50mmol.L-1糖浓度组降低了55%,差异均有显著性(P<0.01);ALP、BGP、Runx2 mRNA表达也均降低,与对照组(5.6mmol.L-1)相比,25mmol.L-1组的ALP、BGP、Runx2 mRNA表达分别降低了21%、12%、15%,差异均有显著性(P<0.05);50mmol.L-1组的ALP、BGP及Runx2 mRNA表达下降也具有显著性(P<0.05)。在3种糖浓度下,与相应组未加PIO相比,PIO干预组,矿化率明显降低,分别降低了20%、25%、25%,差异均有显著性(P<0.05);ALP,BGP及Runx2 mRNA表达水平也显著降低(P<0.01)。结论高糖抑制BMSCs向OB分化,可能为糖尿病性骨质疏松形成的重要机制之一;在高糖条件下,PIO干预可加强抑制BMSCs向OB分化,这也可能是PIO致骨质疏松的重要机制。

Objective To observe the effects of glucose and pioglitazone on rat bone-marrow stromal cells （BMSCs） differentiation into osteoblastic lineages in vitro and to investigate the mechanism of them, Methods Obtain bone-marrow stromal cells from long bone marrow of rat, and interfere them into osteoblasts with different doses of glucose concentration （5.6, 25, and 50 mmol.L-1 ）, alone, with pioglitazone （0.1 μg.mL-1 ） in the presence of an osteogenic medium. The rate of mineralization would be examined by staining of mineralized nodules with Alizarin red S, and the difference of alkaline phosphatase （ALP）, bone gla protein and Runx2 between interblocks was examined by real time PCR. After 21 d of culture. Results The rate of mineralization cut down significantly in higher concentration glucose. Compared with the control group （5,6 mmol.L-1）. The rate of mineralization decreased 21% in 25 mmol.L-1 glucose group, and it deceased 55 % in 50 mmol.L-1 glucose group （ P 〈 0.01 ）. The mRNA expression of ALP, BGP and Runx2 also cut down significantly in higher concentration glucose. Compared with the control group（5.6 mmol.L-1）, them decreased 21%, 12% and 15% in 25 mmol.L-1 glucose group（ P 〈 0,05 ） ; and them also cut down significantly in 50 mmol.L-1 glucose group（ P 〈 0.05）. In triconcentration of glucose, compared with the corresponding control group, the rate of mineralization decreased 20 %, 25 %, 25 % with pioglitazone （ P 〈 0.05 ）, and the mRNA expression of ALP, BGP and Runx2 also cut down significantly with pioglitazone （ P 〈 0,01 ）. Conclusion High concentration glucose inhibited the differentiation of BMSCs into osteoblastics, this observation provide a potential mechanisms of diabetes-induced osteoporosis. Pioglitazone also inhibited osteoblastic of BMSCs, it causes decrease of bone mass by inhibiting osteoblastic and promoting adipogenesis diffenrentiation and it may be the important potential pathogenisis of pioglitazone caused by osteoporosis.