Effect Of Leptin On The Proliferation And Collagen I And Cbfa1 MRNA Expression In Osteoblasts

ObjectiveTo study the effct of leptin on proliferation and expression of CollagenI and CbfalmRNA in primary cultured rat calvarial osteoblasts. And investigate the possible mechanism of action on osteoblasts, provide further theoretical basis for clinical medication.Methods1,Culture rat osteoblasts, and observe their morphology and function.2,The rat osteoblasts are cultured in vitro, the effect of different levels of leptin (O,40,80 and 160ng/ml) on primary cultured rat osteoblasts proliferation is assessed by MTT colorimetry after 24 hours, and then determine their OD mV.3,The osteoblasts are cultured with different dose of leptin (O,40,80 and 160ng/ml). The expression of CollagenI and Cbfal mRNA in primary cultured rat osteoblasts is analyzed by semiquantative RT-PCR.4,Statistical analysis:Data are presented as X±S. All statistical analysis is performed with Windows SPSS 13.0. The differences between the groups are determined by One-way ANOVE. The differences between random two groups are determined by LSD. Differences are considered significant at a value of P<0.05.Results1,Most of primary cultured rat osteoblasts were elongated spindle-shaped. ALP staining was positive. After adding glycerophosphate-βand ascorbic acid-L into the medium, the calcium alizarin red staining was positive.2,Proliferation of primary cultured rat osteoblast was promoted by leptin (0,40,80 and 160ng/ml)after 24 hours. Proliferation of osteoblasts was promoted by leptin; The experimental groups and compared with the control groups were considered significant at a value of P< 0.01.3,Semiquantative RT-PCR examination revealed:leptin promoted CollagenI and Cbfal mRNA expression, in concentration-dependent manner; The experimental groups and compared with the control groups were considered significant at a value of P<0.05.Conclusions1,Leptin promotes proliferation of primary cultured rat osteoblasts.2,Leptin promotes expression of CollagenI and Cbfal mRNA, so as to promote osteoblasts differentiation, accordingly promotes bone formation.