title: Nonalcoholic steatohepatitis, insulin resistance, and metabolic syndrome: further evidence for an etiologic association.
abstract: This study aims to determine the presence of the components of the metabolic syndrome in primary nonalcoholic steatohepatitis (NASH) and to assess the role of liver disease in the genesis of peripheral hyperinsulinemia. Nineteen patients (18 men and 1 woman; mean age, +/- SD, 38 +/- 10 years; body mass index [BMI], 26 +/- 2 kg/m(2)) with histologic evidence of NASH were enrolled; 19 age- and sex-matched normal subjects were investigated as controls. Plasma glucose, insulin, and C-peptide levels were measured during an oral glucose tolerance test, and a frequently sampled intravenous glucose tolerance test (FSIGT), analyzed by minimal modeling technique, was performed. Compared with controls, the NASH group had lower insulin sensitivity (3.84 +/- 2.44 vs. 7.48 +/- 3.01 10(-4) x min(-1)/microU/mL; P =.0003) and higher total insulin secretion (21 +/- 13 vs. 10 +/- 3 nmol/L in 240 minutes; P =.001). Hepatic insulin extraction was similar in both groups (69.8% +/- 16.1% vs. 70.2% +/- 18.3%; P =.854). According to the results of the oral glucose tolerance test, no patient was classified as diabetic, 5 were classified as glucose intolerant, and 1 was classified as having impaired fasting glycemia. Nine patients (47%) had at least the 2 minimum criteria required to define the metabolic syndrome according to the European Group for the Study of Insulin Resistance (EGIR). In conclusion, hyperinsulinemia and insulin resistance occur frequently in patients with NASH; these conditions do not stem from a reduced hepatic insulin extraction but from an enhanced pancreatic insulin secretion compensatory to reduced insulin sensitivity. The derangement of insulin regulation, often associated with the metabolic syndrome, may play a causal role in the pathogenesis of NASH.
authors.affiliation: Department of Internal Medicine, University of Turin, Turin, Italy.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Pagano
authors.forename: Giovanni
authors.initials: G
authors.lastname: Pacini
authors.forename: Giovanni
authors.initials: G
authors.lastname: Musso
authors.forename: Roberto
authors.initials: R
authors.lastname: Gambino
authors.forename: Fabio
authors.initials: F
authors.lastname: Mecca
authors.forename: Nadia
authors.initials: N
authors.lastname: Depetris
authors.forename: Maurizio
authors.initials: M
authors.lastname: Cassader
authors.forename: Ezio
authors.initials: E
authors.lastname: David
authors.forename: Paolo
authors.initials: P
authors.lastname: Cavallo-Perin
authors.forename: Mario
authors.initials: M
authors.lastname: Rizzetto
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D000886:Anthropometry; D005234:Fatty Liver / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D005260:Female; D005951:Glucose Tolerance Test; D006505:Hepatitis / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D006801:Humans; D007328:Insulin / Q000378:metabolism / Q000502:physiology; D007333:Insulin Resistance; D000078790:Insulin Secretion; D008099:Liver / Q000473:pathology; D008297:Male; D024821:Metabolic Syndrome / Q000502:physiology*; D008875:Middle Aged
chemical_list: D007328:Insulin; D000410:Alanine Transaminase