脱氢表雄酮通过丝裂活化蛋白激酶途径促进成骨细胞增殖的研究

目的研究脱氢表雄酮(DHEA)促进成骨细胞增殖的作用和机制。方法取新生2～4d的BALB/c小鼠颅骨,用酶消化法进行成骨细胞原代培养,以细胞形态学和碱性磷酸酶(ALP)染色鉴定。取传1代成骨细胞给予不同浓度DHEA,在不同培养时间后,应用光镜、电镜、四唑盐(MTT)法及流式细胞术(FCM)检测细胞的生长和增殖;同时用免疫印迹法检测磷酸化细胞外信号调控激酶(p44/42)的表达。结果10-8～10-6mol/L的DHEA可明显促进小鼠成骨细胞的生长和增殖,经10-7mol/LDHEA处理3d后的细胞,增殖指数明显增加(P<001);在10-9～10-6mol/L浓度范围内,DHEA能明显提高p44/42的表达,以10-8mol/L浓度的作用最佳(P<001),该作用可被U0126阻断。结论DHEA能够促进小鼠成骨细胞生长和增殖,其作用与激活丝裂活化蛋白激酶信号途径有关。

Effect of dehydroepiandrosterone on the proliferation of murine osteoblasts through mitogen-activated protein kinase signal pathway

Objective To investigate the effect in vitro of dehydroepiandrosterone on the proliferation of murine osteoblasts (OB) and its mechanisms. Methods Murine OB from neonatal BALB/c mice calvaria were digested by collagenase II and cultured in MEM (10?S). OB were treated by dehydroepiandrosterone in different concentration at different time. The biological characteristics of OB were evaluated by phase contrast microscopy, alkaline phosphatase (ALP) histochemistry, transmission electroscope, flow cytometry(FCM)and thiazolyl blue reagents(MTT). The phospho p44/42 expression of the OB was analyzed by Western blotting. Results DHEA in 10 -8 10 -6 mol/L apparently stimulates the growth and the proliferation of murine OB, and the proliferation index was also improved apparently ( P <0 01) after DHEA stimulation (10 -7 mol/L) for three days. The expression of phospho p44/42 was related to the DHEA concentration; moreover, the expression can be blocked by U0126. Conclusions DHEA improves the osteoblastic growth and proliferation, which is related to the signal pathway of mitogen activated protein kinase.