Resistin-binding peptide antagonizes role of resistin on white adipose tissue

Aim: To investigate the direct effects of resistin and resistin-binding peptide (RBP) on lipid metabolism and endocrine function in adipose tissue. Methods: Rat white adipose tissue was cultured in vitro and incubated for 24 h with 30 ng/mL recombinant rat resistin protein (rResistin) or combined with RBP of varying concentrations (1×10 -12 mol/L, 1×10 -10 mol/L, 1×10 -8 mol/L). Free fatty acids (FFA) released into medium was measured by a colorimetric kit. The levels of protein secretion and mRNA expression of TNF-α and adiponectin were detected by ELISA kit and RT-PCR respectively. Results: The levels of FFA released into medium were significantly increased after 24 h of exposure to rResistin, but significantly decreased after RBP was applied, although there was no difference between the 3 concentrations. The protein level and gene expression of TNF-α in adipose tissue were significantly increased after 24 h of exposure to rResistin, but only obviously decreased after incubated with 1×10 -8 mol/L RBP. The levels of protein secretion and mRNA expression of adiponectin in adipose tissue were significantly decreased after 24 h of exposure to rResistin, but increased after incubated with RBP with the higher concentrations. Conclusion: RBP can effectively antagonize the role of resistin on the lipid metabolism and endocrine function of adipose tissue.