Effect of peroxisome proliferator activated receptor gamma agonist on the osteoblasts metabolism in vitro

Objective To explore the effect of peroxisome proliferator activated receptor gamma agonist pioglitazone on the osteoblasts metabolism in rats in vitro.Methods Osteoblasts were obtained from calvaria.After identified as osteoblasts,methyl tetrazolium (MTT) assay and alkaline phosphatase (ALP) detection were used to observe the proliferation and differentiation of osteoblasts stimulated pioglitazone (0,2.5.0,5.0,10.0,20.0 μmoL/L).The protein expression of Smad2/3 and p-Smad3 of osteoblasts induced by transforming growth factor-β1 (TGF-β1) (5 μg/L) was observed by Western blotting.Results Pioglitazone had no effect on stimulating cell proliferation,but the activity of ALP declined from 0.0731 ±0.0041 to 0.0204 ±0.0029 103 U/gprot.Compared to TGF-β1 (5 μg/L),the protein expression of Smad2/3 and p-Smad3 were declined (P ＜ 0.01).Conclusion Peroxisome proliferator activated receptor gamma can inhibit differentiation,and may influence the bone metabolism by regulating the Smad2/3 protein and mRNA expression. Key words: Peroxisome proliferator activated receptor gamma; Osteoblast; Transforming growing factor; Smad