2型糖尿病对大鼠长骨结构与骨髓间充质干细胞增殖分化的影响

Effect of type 2 diabetes on long bone and proliferation and differentiation of bone marrow stem cells in rats

目的:探究2型糖尿病对大鼠长骨生长的结构指标与骨髓间充质干细胞增殖、分化的影响。方法:采用高脂食物诱导构建2型糖尿病大鼠模型,取建模成功的2型糖尿病GK大鼠与对照组Wistar大鼠各8只,显微CT扫描检测胫骨形态计量分析;常规培养股骨骨髓间充质干细胞,应用流式细胞仪和CCK-8试验检测细胞增殖与凋亡活性;成骨分化诱导后应用碱性磷酸酶染色试验和qRT-PCR检测成骨分化活性,应用qRT-PCR检测促炎因子和凋亡因子的表达。结果:高脂食物诱导构建2型糖尿病大鼠模型均成功。与对照组比较,糖尿病组大鼠胫骨长度减少、结构模型参数增加(P<0. 05),骨小梁矿物质密度、骨小梁厚度、骨小梁间距及骨体积分数无明显差异(P>0. 05)。糖尿病组骨髓间充质干细胞增殖活性和成骨分化能力降低,凋亡活性增高,促炎因子IL-1β、IL-6、TNF-α与凋亡因子caspase-3、caspase-8 mRNA表达增高(P<0. 05)。结论:2型糖尿病短期内对大鼠长骨结构的生长无骨质疏松样改变;2型糖尿病抑制大鼠骨髓间充质干细胞的增殖活性及成骨分化能力,促进凋亡活性,抑制骨形成代谢活动。

Objective: To investigate the effects of type 2 diabetes on the growth of rat long bone and the proliferation and differentiation of bone marrow mesenchymal stem cells. Methods: All rat models of type 2 diabetes were induced by high-fat diet. 8 GK rats with type 2 diabetes mellitus and 8 Wistar rats from the control group were selected and the tibia morphometric analysis was performed by microscopic CT scanning. After culture of femur bone marrow mesenchymal stem cells, cell proliferation and apoptosis activity were detected by flow cytometry and CCK-8 test. Osteogenic differentiation activity was detected by alkaline phosphatase staining test and q RT-PCR after osteogenic induction. And qRT-PCR was used to detect the m RNA expression of pro-inflammatory and apoptotic factors. Results: The rat model of type 2 diabetes induced by high fat food was successfully established. Compared with the control group, the length of tibia decreased and the SMI index increased in the diabetic group(P<0.05), while BMD, TbTh, TbSp and BV/TV index were not significantly different(P>0.05). The proliferation activity and the osteogenic differentiation activity of bone marrow mesenchymal stem cells in the diabetic group decreased, while the apoptosis activity increased. Pro-inflammatory factors IL-1β, TNF-α, IL-6 and apoptotic factors caspase-3,caspase-8 m RNA expression significantly increased(P<0.05). Conclusion: Type 2 diabetes has no osteoporosis-like changes effect on the growth of rat long bone structure in the short term. Type 2 diabetes inhibits the proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells, promotes apoptosis and inhibits bone formation metabolism.