The effect of the resistin-binding peptide (RBP) on the 3T3-L1 adipocyte differentiation,lipid metabolism and GLUT-4 gene expression / 中国糖尿病杂志

ABSTRACT

Objective To investigate the effect of RBP on 3T3-L1 adipocyte differentiation,lipid metabolism and glucose transporter 4(GLUT-4)gene expression.Methods We constructed an expression vector for rat resistin gene and transfected it into 3T3-L1 adipocytes.RBP was added to the medium of 3T3-L1 adipocytes or resistin-overexpressing adipocytes on day 0 of differentiation.Cell differentiation and lipid accumulation were determined by oil red O staining.The mRNA expressions of differentiation marker genes(pref-1,C/EBP?,FAS)and GLUT-4 gene were evaluated by RT-PCR.Triglyceride(TG)and free fatty acids(FFAs)in adipocytes were measured by colorimetric kit.Results(1)When 10-12mol/L RBP was applied,the percent of living cells was high and the shape was unchanged.(2)RBP had no effect on the differentiation of normal adipocytes,but significantly decreased the number of lipid droplets in resistin-overexpressing adipocytes without affecting the lipid droplets-presenting day.(3)C/EBP? and FAS expressions in resistin-overexpressing adipocytes were down-regulated after RBP was applied,without changing their expressions in normal adipocytes.(4)RBP had no effect on the cellular TG and FFAs levels in normal cells,whereas it can significantly decrease the levels in resistin-overexpressing adipocytes.(5)There was no difference in the expression of GLUT-4 gene between 3T3-L1 adipocytes and RBP-applied cells.Conclusions(1)RBP has no effect on the cell differentiation and lipid metabolism in normal 3T3-L1 adipocytes.(2)RBP can inhibit the cell differentiation and lipid metabolism of resistin-overexpressing 3T3-L1 cells.(3)RBP has no effect on the expression of GLUT-4 gene.