Abstract:

 Objective   To investigate the effects of leptin on proliferation of HTR8-SVneo cells in vitro and the level of ID(inhibitor of DNA binding and differentiation), and to explore the regulatory mechanism of leptin underlying HTR8-SVneo cell proliferation. Methods   The proliferation of HTR8-SVneo cells cultured in vitro under diverse concentrations (0, 10, 50, 100, 250 and 500ng/mL) of leptin was tested by means of MTT. Then, HTR8-SVneo cells were treated with leptin (0, 100 and 500ng/mL), and leptin receptor(leptin R) profiling, ID mRNA profiling and the level of the ID2 protein were detected by RT-PCR, real-time PCR and Western blot, respectively. To observe the effect of leptin on HTR8-SVneo cell proliferation after ID2-siRNA treatment, HTR8-SVneo cells were divided into 6 groups: leptin(0ng/mL), leptin(100ng/mL), leptin(500ng/mL), leptin(0ng/mL)+ID2-siRNA, leptin(100ng/mL)+ID2-siRNA and leptin(500ng/mL)+ID2-siRNA. Results   Proliferation of HTR8-SVneo cells was enhanced by high concentrations of leptin (100, 250 and 500ng/mL) compared with leptin (0ng/mL) (P<0.05). Leptin receptor subtypes except HuB219.2 were detected on HTR8-SVneo cells. The up-regulation of ID2 or OB-RL was induced by leptin in a dosedependent manner. ID2-siRNA inhibited expression of the ID2 protein and reversed the enhancement of HTR8-SVneo cell proliferation induced by leptin. Conclusion   Leptin enhances HTR8-SVneo cell proliferation by the pathway of leptin R-ID2, which offers new basal data for elucidating the regulatory mechanism of proliferation of trophocytes.

Key words: Leptin; Leptin receptor; HTR8-SVneo cells; Inhibitor of differentiation 2; Proliferation