Effect of Leptin on the Expression of Chemokine Genes in THP-1 Cells

Choi, Jin Hee; Park, Ho Sun; Lee, Tae Yoon; Kim, Sung Kwang; Kim, Hee Sun

Abstract

BACKGROUND: Leptin is a 16-KDa non-glycosylated peptide hormone synthesized almost exclusively by adipocytes. The well-known function of leptin is regulation of food intake and energy expenditure. Leptin also plays a regulatory role in immune and inflammatory process including cytokine production. The purpose of this study was to investigate the effect of leptin on the expression of several chemokine genes(RANTES, IL-8, MCP-1, IP-10, Mig, MIP-1alpha, MIP-1beta, and GRO-alpha) in THP-1 cells.
MATERIALS AND METHODS
Total RNA of THP-1 cells were prepared by Trizol method, and then stimulated with the leptin(250 ng/microliter) or LPS(100 ng/microliter). We examined the expression patterns of various chemokine mRNAs in THP-1 cell lines by RT-PCR and Northern blot.
RESULTS
Leptin did not induce the expression of chemokine mRNAs in THP-1 cells. The expression patterns of RANTES, IL-8, MCP-1, IP-10, and Mig mRNAs in THP-1 cells stimulated with leptin and LPS simultaneously was almost same to the patterns of LPS alone-induced chemokine mRNAs. RANTES mRNA expression was independent on the concentrations of leptin. Although leptin did not have strong effect on the expression of RANTES, IL-8, MCP-1, IP-10, Mig, MIP-1alpha, MIP-1beta, and GRO-alpha mRNAs in THP-1 cells, leptin could induce the expression of long isoform of leptin receptor(OB-RL) mRNA, and its expression was elevated in simultaneous stimulation of leptin and LPS.
CONCLUSION
These data suggest that leptin is able to induce OB-RL in THP-1 cells, however, leptin has little effect on the expression of pro-inflammatory chemokine genes.