Glucagon-like peptide 1 decreases lipotoxicity in non-alcoholic steatohepatitis.

Background & Aims Insulin resistance and lipotoxicity are pathognomonic in non-alcoholic steatohepatitis (NASH). Glucagon-like peptide-1 (GLP-1) analogues are licensed for type 2 diabetes, but no prospective experimental data exists in NASH. This study determined the effect of a long-acting GLP-1 analogue, liraglutide, on organ-specific insulin sensitivity, hepatic lipid handling and adipose dysfunction in biopsy-proven NASH. Methods Fourteen patients were randomised to 1.8mg liraglutide or placebo for 12-weeks of the mechanistic component of a double-blind, randomised, placebo-controlled trial (ClinicalTrials.gov-NCT01237119). Patients underwent paired hyperinsulinaemic euglycaemic clamps, stable isotope tracers, adipose microdialysis and serum adipocytokine/metabolic profiling. In vitro isotope experiments on lipid flux were performed on primary human hepatocytes. Results Liraglutide reduced BMI (−1.9 vs . +0.04kg/m 2 ; p 0.001), HbA1c (−0.3 vs . +0.3%; p 0.01), cholesterol-LDL (−0.7 vs . +0.05mmol/L; p 0.01), ALT (−54 vs. −4.0IU/L; p 0.01) and serum leptin, adiponectin, and CCL-2 (all p 0.05). Liraglutide increased hepatic insulin sensitivity (−9.36 vs . −2.54% suppression of hepatic endogenous glucose production with low-dose insulin; p 0.05). Liraglutide increased adipose tissue insulin sensitivity enhancing the ability of insulin to suppress lipolysis both globally (−24.9 vs . +54.8pmol/L insulin required to ½ maximally suppress serum non-esterified fatty acids; p 0.05), and specifically within subcutaneous adipose tissue ( p 0.05). In addition, liraglutide decreased hepatic de novo lipogenesis in vivo (−1.26 vs . +1.30%; p 0.05); a finding endorsed by the effect of GLP-1 receptor agonist on primary human hepatocytes (24.6% decrease in lipogenesis vs . untreated controls; p 0.01). Conclusions Liraglutide reduces metabolic dysfunction, insulin resistance and lipotoxicity in the key metabolic organs in the pathogenesis of NASH. Liraglutide may offer the potential for a disease-modifying intervention in NASH.