Burroughs Wellcome Fund and American Diabetes Association.

The prevalence of NAFLD is much higher than previously believed in overweight/obese patients with T2DM and normal aminotransferases. Moreover, many are at increased risk of NASH. Physicians should have a lower threshold for screening patients with T2DM for NAFLD/NASH.

The role of adipose tissue insulin resistance in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) remains unclear. To evaluate this, we measured in 207 patients with NAFLD (age = 51 ± 1, body mass index = 34.1 ± 0.3 kg/m2) and 22 controls without NAFLD (no NAFLD) adipose tissue insulin resistance by means of a validated index (Adipo‐IRi = plasma free fatty acids [FFA] x insulin [FPI] concentration) and as the suppression of plasma FFA during an oral glucose tolerance test and by a low‐dose insulin infusion. We also explored the relationship between adipose tissue insulin resistance with metabolic and histological parameters by dividing them based on quartiles of adipose tissue insulin resistance (Adipo‐IRi quartiles: Q1 = more sensitive; Q4 = more insulin resistant). Hepatic insulin resistance, measured as an index derived from endogenous glucose production x FPI (HIRi), and muscle insulin sensitivity, were assessed during a euglycemic insulin clamp with 3‐[3H] glucose. Liver fat was measured by magnetic resonance imaging and spectroscopy, and a liver biopsy was performed to assess liver histology. Compared to patients without steatosis, patients with NAFLD were insulin resistant at the level of adipose tissue, liver, and skeletal muscle and had higher plasma aspartate aminotransferase and alanine aminotransferase, triglycerides, and lower high‐density lipoprotein cholesterol and adiponectin levels (all P < 0.01). Metabolic parameters, hepatic insulin resistance, and liver fibrosis (but not necroinflammation) deteriorated as quartiles of adipose tissue insulin resistance worsened (all P < 0.01). Conclusion: Adipose tissue insulin resistance plays a key role in the development of metabolic and histological abnormalities of obese patients with NAFLD. Treatment strategies targeting adipose tissue insulin resistance (e.g., weight loss and thiazolidinediones) may be of value in this population. (HEPATOLOGY 2012)

OBJECTIVE While vitamin E has shown to improve nonalcoholic steatohepatitis (NASH) in patients without diabetes, information on patients with type 2 diabetes mellitus (T2DM) is lacking. The aim of this study was to determine whether vitamin E, alone or combined with pioglitazone, improves histology in patients with T2DM and NASH. RESEARCH DESIGN AND METHODS This was a proof-of-concept, randomized, double-blind, placebo-controlled trial conducted from 2010 to 2016. Patients with T2DM and biopsy-proven NASH (n = 105) were randomized to vitamin E 400 IU b.i.d., vitamin E 400 IU b.i.d. plus pioglitazone 45 mg/day, or placebo. Eighty-six patients completed the 18-month study. The primary end point was a two-point reduction in the nonalcoholic fatty liver disease activity score from two different parameters, without worsening of fibrosis. Secondary outcomes were resolution of NASH without worsening of fibrosis, individual histological scores, and metabolic parameters. RESULTS More patients on combination therapy achieved the primary outcome versus placebo (54% vs. 19%, P = 0.003) but not with vitamin E alone (31% vs. 19%, P = 0.26). Both groups showed improvements in resolution of NASH compared with placebo (combination group: 43% vs. 12%, P = 0.005; vitamin E alone: 33% vs. 12%, P = 0.04). While steatosis assessed by histology improved with combination therapy (P &lt; 0.001) and vitamin E alone (P = 0.018), inflammation (P = 0.018) and ballooning (P = 0.022) only improved with combination therapy. No improvement in fibrosis was observed in any group. CONCLUSIONS In this proof-of-concept study, combination therapy was better than placebo in improving liver histology in patients with NASH and T2DM. Vitamin E alone did not significantly change the primary histological outcome.