Objective: To investigate the effect of resistin overexpression on 3T3-L1 adipocyte lipid and glucose metabolism.
Methods: Expression vector for rat resistin gene was constructed and transfected into 3T3-L1 adipocytes. Cell differentiation and lipid accumulation was determined by Oil Red O staining. Differentiation marker genes (pref-1, C/EBPalpha, FAS) and glucose transporter 4 (GLUT4) gene mRNA expressions were evaluated by reverse transcription-PCR (RT-PCR). Triglyceride (TG) and free fatty acids (FFAs) in adipocytes were measured by colorimetric kit.
Results: (1) In resistin-overexpressed adipocytes, the lipid droplets presented at the second day which was earlier than the control cells. (2) The expression of C/EBPalpha and FAS genes in resistin-overexpressed adipocytes were up-regulated and the pref-1 was down-regulated compared with that of the control cells. (3) In resistin-overexpressed adipocytes, cellular TG and FFAs levels were significantly increased (P<0.05). (4) There was no difference in the expression of GLUT4 gene between 3T3-L1 adipocytes and resistin-overexpressed adipocytes (P> 0.05).
Conclusion: Overexpression of resistin can affect 3T3-L1 adipocyte lipid metabolism and thereby result in obesity and insulin resistance, but have no effect on GLUT4 gene expression.