Elevated plasma leptin concentrations in early stages of experimental intestinal inflammation in rats

Abstract
Background—Although leptin, an adipocyte derived hormone which regulates food intake and energy balance, is released after injections of tumour necrosis factor (TNF) and interleukin 1, plasma concentrations have not been characterised in chronic inflammation. Leptin may contribute to the anorexia and body weight loss associated particularly with the acute stages of inflammatory bowel disease. Aims—To investigate plasma leptin concentrations during the time course of intestinal inflammation in different animal models. Methods—Plasma leptin was measured at different time points in rats with trinitrobenzene sulphonic acid (TNBS) induced colitis, indomethacin induced ileitis, or endotoxic shock caused by lipopolysaccharide (LPS). Systemic TNF-α was also measured during acute inflammation. Results—Plasma leptin concentrations increased fourfold eight hours after induction of TNBS colitis (pConclusion—Elevated plasma leptin concentrations, correlated with the degree of inflammation and associated with anorexia, were induced in rats during the early stages of experimental intestinal inflammation but proved transient; this might account for discrepancies in recent results concerning concentrations in patients with inflammatory bowel diseases.