Obeticholic Acid Modulates Serum Metabolites and Gene Signatures Characteristic of Human NASH and Attenuates Inflammation and Fibrosis Progression in Ldlr‐/‐.Leiden Mice

Abstract

Concerns have been raised about whether preclinical models sufficiently mimic molecular disease processes observed in nonalcoholic steatohepatitis (NASH) patients, bringing into question their translational value in studies of therapeutic interventions in the process of NASH/fibrosis. We investigated the representation of molecular disease patterns characteristic for human NASH in high‐fat diet (HFD)‐fed Ldlr‐/‐.Leiden mice and studied the effects of obeticholic acid (OCA) on these disease profiles. Multiplatform serum metabolomic profiles and genome‐wide liver transcriptome from HFD‐fed Ldlr‐/‐.Leiden mice were compared with those of NASH patients. Mice were profiled at the stage of mild (24 weeks HFD) and severe (34 weeks HFD) fibrosis, and after OCA intervention (24‐34 weeks; 10 mg/kg/day). Effects of OCA were analyzed histologically, biochemically, by immunohistochemistry, using deuterated water technology (de novo collagen formation), and by its effect on the human‐based transcriptomics and metabolomics signatures. The transcriptomics and metabolomics profile of Ldlr‐/‐.Leiden mice largely reflected the molecular signature of NASH patients. OCA modulated the expression of these molecular profiles and quenched specific proinflammatory‐profibrotic pathways. OCA attenuated specific facets of cellular inflammation in liver (F4/80‐positive cells) and reduced crown‐like structures in adipose tissue. OCA reduced de novo collagen formation and attenuated further progression of liver fibrosis, but did not reduce fibrosis below the level before intervention. Conclusion: HFD‐fed Ldlr‐/‐.Leiden mice recapitulate molecular transcriptomic and metabolomic profiles of NASH patients, and these signatures are modulated by OCA. Intervention with OCA in developing fibrosis reduces collagen deposition and de novo synthesis but does not resolve already manifest fibrosis in the period studied. These data show that human molecular signatures can be used to evaluate the translational character of preclinical models for NASH.

A Microphysiological System for Studying Nonalcoholic Steatohepatitis

“…To evaluate the pharmacological response of the in vitro NASH model, the prototypic anti-NASH compound OCA, currently being evaluated in phase III trials, was repeat-dosed for 1 week. Most prominently we observed OCA to reduce a number of inflammatory markers in the NASH model, corroborating the results by other preclinical studies (18,19,46) and those from phase II clinical trials. (33) Interestingly we observed a significant decrease in IL-6 production, but only a minimal effect on gene expression, suggesting that OCA affects the translation, posttranslational modification, or secretion of this cytokine.…”

“…(47) One reason why OCA appears to be a promising candidate drug is that it affects not only inflammation and fibrosis, but it also affects the metabolic processes associated with NASH. (46,47) Supporting this idea, we observed up-regulation of a number of genes associated with glucose metabolism following OCA dosing, including G6PC, which is reported to be strongly influenced by OCA dosing in other preclinical models. (9) The developed co-culture NASH model should now be explored with a wide range of compounds with varying mechanisms of action to demonstrate its full utility for use in the drug discovery process.…”

A Translational Mouse Model for NASH with Advanced Fibrosis and Atherosclerosis Expressing Key Pathways of Human Pathology

“…There is practically no fibrosis development in wild-type mice fed high-fat diets without cholesterol supplementation. Lobular inflammation in the Ldlr−/−.Leiden model consisted of a mixed inflammatory cell type of mononuclear cells and polymorphonuclear cells that formed aggregates and that have previously been characterized in more detail and stained positive for F4/80 (macrophages), CD-4 (T helper cells), and CD-8 (cytotoxic T cells) [11], as well as MPO (neutrophils) [10]. In the Ldlr−/−.Leiden mice fed a HFD or FFD, hepatic fibrosis was present in a pattern characteristic for dietary induction and resembling the human situation (in contrast to the induction by chemical toxins).…”

“…Data of FFD for 12 weeks were obtained by taking a liver biopsy of the mice that continued on the FFD for 22 weeks and are from a separate group of animals than mice that were fed the different diets for 28 weeks. In addition, mice were fed the FFD and treated with a relatively low dose of obeticholic acid (OCA) ( To validate whether the Ldlr−/−.Leiden mice on FFD respond to treatment with pharmaceutical intervention, Ldlr−/−.Leiden mice were fed the FFD supplemented with an established [11] and relatively low dose of OCA (10 mg/kg/d) from week 18 to 28. OCA treatment did not significantly affect body weight (50.4 ± 2.6 g), food intake (14.0 ± 0.4 kCal/mouse/day), or liver weight (4.0 ± 0.5 g) as compared to the untreated FFD fed animals ( Table 1).…”

“…In the current study, we investigated whether Ldlr−/−.Leiden mice, which are genetically predisposed to develop CVD and that have been extensively characterized for recapitulating features of metabolic syndrome and NASH [7,[10][11][12][13][14][15][16][17], would represent a translational model in which advanced stages of liver fibrosis can be studied in conjunction with atherosclerosis. Ldlr−/−.Leiden mice display histopathological characteristics of NASH, in the context of obesity, hyperlipidemia, and hyperinsulinemia, when fed energy-dense diets with macronutrient composition comparable to human diets [14].…”