TGF-β对成骨细胞增殖、分化及OPG基因mRNA表达的影响

Effect of TGF-β on the proliferation and differentiation and gene expression in rat osteoblast

目的 观察不同剂量TGF-β对成骨细胞增殖、分化及OPGmRNA基因表达的影响,明确其作用机理。方法 取新生24h内的Wistar大鼠颅盖骨分离成骨细胞,在TGF-β为Oμg/L、1μg/L、10μg/L、100μg/L的浓度中培养。对细胞的生长及钙结节的形成观察其生长状态,经MTT法测定细胞增殖,细胞分化由碱性磷酸酶(ALP)和骨钙素(OCN)水平测定得到。用RT-PCR技术测定TGF-β对成骨细胞OPC基因mRNA表达的影响。结果 成骨细胞在7d可铺满瓶壁,30d可形成钙结节,TGF-β可促进成骨细胞的增殖、ALP和OCN的分泌,以TGF-β为1μg/L时作用明显。TGF-β可促进OPG基因的表达在为1μg/L时作用明显。结论 1μg/L可促进大鼠成骨细胞的增殖、分化,促进成骨细胞OPG基因mRNA的表达。TGF-β可能通过影响OPG而调节成骨细胞、破骨细胞的平衡,使骨重建。

Objectivc To assess the effect of TGF-β on the proliferation and differentiation and gene expres- sion in rat osteoblast and to investigate the mechanism of OPC in osteoporosis. Methods Osteoblast obtained from the calvariae of newborn rats were cultured in the medium with different concentrations of TGF-β. Cell proliferation was de- tected hy optical microscope and MTT method. The differentiation was determined by measuring alkaline phosphatase (ALP) activity and osteocalcin secretion. OPG gene expression was quantified by RT-PCR. Results TGF-β in low dose (1μg/L P<0.05) obviously increased osteoblast proliferation and differentiation and the gene expression of OPG. Conclusion TGF-β stimulates osteoblast proliferation and differentiation, especially in low dose, so does in the gene expression of OPG. TGF-β regulates the balance between osteoblast and osteoclast by affecting gene expression of OPG