Increased plasma ghrelin following infliximab in Crohn’s disease

Background Ghrelin, a potent orexigenic peptide produced by the stomach, may be affected by circulating inflammatory mediators. Aim To assess the effect of an anti-TNF alpha antibody on ghrelin in patients with Crohn's disease (CD). Methods Fifteen patients with Crohn's receiving infliximab were studied before and 1 week after infusion. Following an overnight fast, blood was sampled before a meal and then every 20 min for 2 h. Total ghrelin and CRP were measured using ELISA. Acylated ghrelin and TNF alpha, IFN gamma, IL-1 beta and IL-6 were measured with bioplex. Harvey Bradshaw Activity Index was assessed. Results Median (95% CI) 2-h integrated plasma total ghrelin increased from 162 (99-311) before infliximab to 200 (128-387) pg/mL h, (P = 0.02) after. Following infliximab, 20 min postmeal, median acylated ghrelin decreased from 50.3 (24-64) to 38.6 (26-82) pg/mL, (P = 0.04) thus reverting to a traditional meal related ghrelin curve. Median (range) disease activity decreased from 5 (2-28) before to 3 (0-22), (P = 0.0001) and Median (95% CI) TNFa decreased from 2.8 (1.89-4.48) to 1.31 (0.73-2.06) pg/mL (P = 0.002). Conclusions Infliximab increases circulating total ghrelin by 25% in CD and restores the postprandial response of acylated ghrelin to food intake. Acylated and de-sacyl ghrelin remain unchanged, suggesting that an alternate isoform could be affected by infliximab.