Insulin-like growth factor I correlates with MELD and returns to normal level after liver transplantation

Abstract

Insulin-like growth factor I (IGF-I) is produced almost entirely by the liver and is the main promoter of anabolic growth hormone (GH) effects on protein, carbohydrate, and lipid metabolism. IGF-I is significantly decreased in patients with liver cirrhosis. Our objective was to determine the relationship between circulating IGF-I and MELD (Model for End-stage Liver Disease) in cirrhotics subjected to orthotopic liver transplantation (OLT). We also assessed the changes of IGF-I and its major binding protein (IGF-binding protein-3 or IGFBP-3) after OLT. In a prospective study, serum levels of IGF-I and IGFBP-3 of 25 male adult patients with end-stage liver disease were measured 2 to 4 hours before and 6 months after orthotopic liver transplantation. Seven age-matched healthy male volunteers with normal liver enzymes, albumin, and prothrombin time served as controls. MELD was determined on the day of OLT. For this analysis, extra points were not added for patients with hepatocarcinoma. The cirrhotic group had significantly lower IGF-I (46.7±21.6 ng/mL) and IGFBP-3 (1.0±0.9 ng/mL) levels in the pre-transplant period compared with the controls (208.6±76.5 ng/mL and 4.62±0.93 ng/mL, respectively) (p<0.05). There was a negative correlation between IGF-I or IGFBP-3 and MELD (p<0.001) (ß=-1.750; standard error =2.5054 and ß=-0.038; standard error <0.0001, respectively). IGF-I e IGFBP-3 increased to normal levels after OLT (207.7±82.8 and 4.14±1.1 ng/mL, respectively) (p<0.001). Low levels of IGF-I and IGFBP-3 observed in patients with advanced liver cirrhosis are corrected after OLT. IGF-I and IGFBP-3 correlate negatively with MELD.