Li Liu1, Hailun Gu, Jun Yang, Fei Yu. 1. School of Public Health, China Medical University, Shenyang 110001, China. liuli@mail.cmu.edu.cn
Abstract
OBJECTIVE: To study the effect of rat recombinant leptin on expressions of suppressor of cytokine signaling 3 (SOCS-3) mRNA and protein in mature adipocytes . METHODS: Mature adipocytes were separated from epididymal adipose tissues of male SD rats, and the expressions of long-form leptin receptor mRNA were detected. The separated adipocytes were then treated with rat recombinant leptin at the doses of 0.5-500 nmol/L for 0.5 to 6h. The expressions of SOCS-3 mRNA were measured with RT-PCR and proteins were measured with immuniprecipitation combined with Western blot analysis. RESULTS: Low-level expressions of long-form leptin receptor mRNA could be measured in mature adipocytes. The adipocytes expressed small amounts of SOCS-3 mRNA and protein witbout leptin treatment, and no significant changes were observed at 0.5 Snmol/L of leptin. However, tbe expressions of SOCS-3 mRNA and protein increased significantly at the doses of 5-500 nmol/L of leptin in the consistent with treatment time. CONCLUSION: Leptin could have direct effects on adipocytes. High leptin concentration could induce the expressions of SOCS-3 mRNA and protein in mature adipocytes.
OBJECTIVE: To study the effect of rat recombinant leptin on expressions of suppressor of cytokine signaling 3 (SOCS-3) mRNA and protein in mature adipocytes . METHODS: Mature adipocytes were separated from epididymal adipose tissues of male SD rats, and the expressions of long-form leptin receptor mRNA were detected. The separated adipocytes were then treated with rat recombinant leptin at the doses of 0.5-500 nmol/L for 0.5 to 6h. The expressions of SOCS-3 mRNA were measured with RT-PCR and proteins were measured with immuniprecipitation combined with Western blot analysis. RESULTS: Low-level expressions of long-form leptin receptor mRNA could be measured in mature adipocytes. The adipocytes expressed small amounts of SOCS-3 mRNA and protein witbout leptin treatment, and no significant changes were observed at 0.5 Snmol/L of leptin. However, tbe expressions of SOCS-3 mRNA and protein increased significantly at the doses of 5-500 nmol/L of leptin in the consistent with treatment time. CONCLUSION:Leptin could have direct effects on adipocytes. High leptin concentration could induce the expressions of SOCS-3 mRNA and protein in mature adipocytes.