Nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease in the Western world. NAFLD is a complex spectrum of liver diseases ranging from benign hepatic steatosis to its more aggressive necroinflammatory manifestation, nonalcoholic steatohepatitis (NASH). NASH pathogenesis is multifactorial and risk factors are almost identical to those of the metabolic syndrome. This has prompted substantial efforts to identify novel drug therapies for correcting underlying metabolic deficits, and to prevent or alleviate hepatic fibrosis in NASH. Available mouse models of NASH address different aspects of the disease, have varying clinical translatability, and, therefore, also show different utility in drug discovery.

Author contributions: Kristiansen MNB, Veidal SS, Rigbolt KTG, Tølbøl KS and Feigh M performed the experiments and analyzed the data; Rigbolt KTG performed the molecular investigations; Kristiansen MNB and Veidal SS performed the histological analysis; Veidal SS, Rigbolt KTG, Roth JD, Jelsing J, Vrang N and Feigh M designed and coordinated the research; Kristiansen MNB, Veidal SS, Rigbolt KTG, Tølbøl KS, Roth JD, Jelsing J, Vrang N and Feigh M wrote the paper.Institutional review board statement: This study includes no data or material from patients. We confirm that all of the required permissions for this study were obtained from our local authorities as mentioned in the Institutional animal care and use committee statement.Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Danish Committee for animal research and covered by a personal license for Jacob Jelsing (2013-15-2934-00784). All of the institutional and national guidelines for the care and use of laboratory animals were followed.Conflict-of-interest statement: There are no patents, products in development or marked products to declare. Abstract AIM: To characterize development of diet-induced nonalcoholic steatohepatitis (NASH) by performing liver biopsy in wild-type and genetically obese mice. METHODS:Male wild-type C57BL/6J (C57) mice (DIO-NASH) and male Lep ob /Lep ob (ob /ob ) mice (ob /ob -NASH) were maintained on a diet high in trans-fat (40%), fructose (22%) and cholesterol (2%) for 26 and 12 wk, respectively. A normal chow diet served as control in C57 mice (lean chow) and ob /ob mice (ob /ob chow).After the diet-induction period, mice were liver biopsied and a blinded histological assessment of steatosis and fibrosis was conducted. Mice were then stratified into groups counterbalanced for steatosis score and fibrosis stage and continued on diet and to receive daily PO dosing of vehicle for 8 wk. Global gene expression in liver tissue was assessed by RNA sequencing and bioinformatics. Metabolic parameters, plasma liver enzymes and lipids (total cholesterol, triglycerides) as well as hepatic lipids and collagen content were measured by biochemical analysis. Non-alcoholic fatty liver disease activity score (NAS) (steatosis/inflammation/ballooning Obese diet-induced mouse models of nonalcoholic steatohepatitis-tracking disease by liver biopsy Basic Study ORIGINAL ARTICLEdegeneration) and fibrosis were scored. Steatosis and fibrosis were also quantified using percent fractional area. RESULTS: Diet-induction for 26 and 12 wk in DIO-NASH and ob /ob -NASH mice, respectively, elicited progressive metabolic perturbations characterized by increased adiposity, total cholesterol and elevated plasma liver enzymes. The diet also induced clear histological features of NASH including hepatosteatosis and fibrosis. Overall, the metabolic NASH phenotype was more pronounced in ob /ob -NASH vs DIO-NASH mice. During the eight week repeated vehicle dosing period, the metabolic phenotype was sustai...

AimsTo characterize the pharmacology of MEDI0382, a peptide dual agonist of glucagon‐like peptide‐1 (GLP‐1) and glucagon receptors.Materials and methods MEDI0382 was evaluated in vitro for its ability to stimulate cAMP accumulation in cell lines expressing transfected recombinant or endogenous GLP‐1 or glucagon receptors, to potentiate glucose‐stimulated insulin secretion (GSIS) in pancreatic β‐cell lines and stimulate hepatic glucose output (HGO) by primary hepatocytes. The ability of MEDI0382 to reduce body weight and improve energy balance (i.e. food intake and energy expenditure), as well as control blood glucose, was evaluated in mouse models of obesity and healthy cynomolgus monkeys following single and repeated daily subcutaneous administration for up to 2 months.Results MEDI0382 potently activated rodent, cynomolgus and human GLP‐1 and glucagon receptors and exhibited a fivefold bias for activation of GLP‐1 receptor versus the glucagon receptor. MEDI0382 produced superior weight loss and comparable glucose lowering to the GLP‐1 peptide analogue liraglutide when administered daily at comparable doses in DIO mice. The additional fat mass reduction elicited by MEDI0382 probably results from a glucagon receptor‐mediated increase in energy expenditure, whereas food intake suppression results from activation of the GLP‐1 receptor. Notably, the significant weight loss elicited by MEDI0382 in DIO mice was recapitulated in cynomolgus monkeys.ConclusionsRepeated administration of MEDI0382 elicits profound weight loss in DIO mice and non‐human primates, produces robust glucose control and reduces hepatic fat content and fasting insulin and glucose levels. The balance of activities at the GLP‐1 and glucagon receptors is considered to be optimal for achieving weight and glucose control in overweight or obese Type 2 diabetic patients.

AIMTo evaluate the pharmacodynamics of compounds in clinical development for nonalcoholic steatohepatitis (NASH) in obese mouse models of biopsy-confirmed NASH.METHODSMale wild-type C57BL/6J mice (DIO-NASH) and Lepob/ob (ob/ob-NASH) mice were fed a diet high in trans-fat (40%), fructose (20%) and cholesterol (2%) for 30 and 21 wk, respectively. Prior to treatment, all mice underwent liver biopsy for confirmation and stratification of liver steatosis and fibrosis, using the nonalcoholic fatty liver disease activity score (NAS) and fibrosis staging system. The mice were kept on the diet and received vehicle, liraglutide (0.2 mg/kg, SC, BID), obeticholic acid (OCA, 30 mg/kg PO, QD), or elafibranor (30 mg/kg PO, QD) for eight weeks. Within-subject comparisons were performed on changes in steatosis, inflammation, ballooning degeneration, and fibrosis scores. In addition, compound effects were evaluated by quantitative liver histology, including percent fractional area of liver fat, galectin-3, and collagen 1a1.RESULTSLiraglutide and elafibranor, but not OCA, reduced body weight in both models. Liraglutide improved steatosis scores in DIO-NASH mice only. Elafibranor and OCA reduced histopathological scores of hepatic steatosis and inflammation in both models, but only elafibranor reduced fibrosis severity. Liraglutide and OCA reduced total liver fat, collagen 1a1, and galectin-3 content, driven by significant reductions in liver weight. The individual drug effects on NASH histological endpoints were supported by global gene expression (RNA sequencing) and liver lipid biochemistry.CONCLUSIONDIO-NASH and ob/ob-NASH mouse models show distinct treatment effects of liraglutide, OCA, and elafibranor, being in general agreement with corresponding findings in clinical trials for NASH. The present data therefore further supports the clinical translatability and utility of DIO-NASH and ob/ob-NASH mouse models of NASH for probing the therapeutic efficacy of compounds in preclinical drug development for NASH.

Non-alcoholic fatty liver disease and steatohepatitis are highly associated with obesity and type 2 diabetes mellitus. Cotadutide, a GLP-1R/GcgR agonist, was shown to reduce blood glycemia, body weight and hepatic steatosis in patients with T2DM. Here, we demonstrate that the effects of Cotadutide to reduce body weight, food intake and improve glucose control are predominantly mediated through the GLP-1 signaling, while, its action on the liver to reduce lipid content, drive glycogen flux and improve mitochondrial turnover and function are directly mediated through Gcg signaling. This was confirmed by the identification of phosphorylation sites on key lipogenic and glucose metabolism enzymes in liver of mice treated with Cotadutide. Complementary metabolomic and transcriptomic analyses implicated lipogenic, fibrotic and inflammatory pathways, which are consistent with a unique therapeutic contribution of GcgR agonism by Cotadutide in vivo . Significantly, Cotadutide also alleviated fibrosis to a greater extent than Liraglutide or Obeticholic acid (OCA), despite adjusting dose to achieve similar weight loss in 2 preclinical mouse models of NASH. Thus Cotadutide, via direct hepatic (GcgR) and extra-hepatic (GLP-1R) effects, exerts multi-factorial improvement in liver function and is a promising therapeutic option for the treatment of steatohepatitis.