Insulin resistance is present in nearly all patients with liver cirrhosis, but its etiology remains unclear. Recent studies have shown that tumor necrosis factor-alpha (TNF-alpha) system is involved in the insulin resistance of human obesity. Serum concentrations of TNF-alpha, and 2 soluble TNF receptors (sTNF-RI and sTNF-RII) are increased in cirrhotic patients. This study explored whether TNF-a system activity was associated with insulin resistance in liver cirrhosis. A total of 26 male nondiabetic patients with liver cirrhosis (mean age, 59 +/- 3 years; body mass index, 23.7 +/- 0.4 kg/m(2)) and 25 male control subjects (age, 65 +/- 2 years; body mass index, 24.4 +/- 0.5 kg/m(2)) were studied. Serum insulin, c-peptide, TNF-a, sTNF-RI, and sTNF-RII concentrations were determined by immunoassay. The insulin resistance was estimated by homeostasis assessment model (HOMA IR). In cirrhotic patients, serum levels of TNF-alpha, sTNF-RI, and sTNF-RII were all higher than those in the controls, and correlated with disease severity. Also, the serum c-peptide, insulin concentrations, and the HOMA IR were higher in liver cirrhosis with comparable blood glucose to control subjects, indicating a degree of insulin insensitivity. In the whole population, there was a moderate, but statistically significant, correlation between serum sTNF-RI or sTNF-RII, and HOMA IR. Also, body mass index was associated with HOMA IR, but not related to serum TNF-alpha, and sTNF-Rs levels. In multiple regression analysis, both sTNF-RII and body mass index jointly contributed to 30% variance of HOMA IR. Our study demonstrated that elevated sTNF-RII levels were associated with insulin resistance in liver cirrhosis. The data indicated that TNF-alpha system might play a role in modulating insulin action in patients with liver cirrhosis. (C) 2004 Elsevier Inc. All rights reserved.