Altered fasting and postprandial plasma ghrelin levels in patients with liver failure are normalized after liver transplantation

Context: Anorexia is a problem of paramount importance in patients with advanced liver failure. Ghrelin has important actions on feeding and weight homeostasis. Experimental data exist, which suggest that ghrelin could protect hepatic tissue. Both fasting and post-oral glucose tolerance test (OGTT) ghrelin concentrations are controversial in liver cirrhosis and are unknown after liver transplantation. Objective: Our aim was to study fasting ghrelin concentrations and their response to an OGTT in liver failure patients before and after liver transplantation. Design and methods: We included 21 patients with severe liver failure studied before (pretransplantation, PreT) and 6 months after liver transplantation (posttransplantation, PostT), and 10 age-and body mass index-matched healthy or overweight subjects as the control group (Cont). After an overnight fast, 75 g of oral glucose were administered; glucose, insulin, and ghrelin were obtained at baseline and at times 30, 60, 90, and 120 min. Results: Fasting ghrelin (median and range, pg/ml) levels were lower in PreT: 539 (309-1262) than in Cont: 643 (523-2163), P=0.045. Fasting ghrelin levels increased after liver transplantation, 539 (309-1262) vs 910 (426-3305), for PreT and PostT respectively, P=0.001. The area under the curve (AUC) of ghrelin (pg/ml min) was lower in PreT: 63 900 (37 260-148 410) than in Cont: 76 560 (56 160-206 385), P=0.027. The AUC of ghrelin increased in PostT, 63 900 (37 260-148 410) vs 107 595 (59 535-357 465), for PreT and PostT respectively, P=0.001. Fasting levels and the AUC of ghrelin were similar in PosT and Cont. Conclusions: Decreased fasting and post-OGTT ghrelin levels in liver failure patients were normalized after liver transplantation.