Research Article Details

Article ID: A08745
PMID: 32003601
Source: Am J Physiol Gastrointest Liver Physiol
Title: Dysregulated FXR-FGF19 signaling and choline metabolism are associated with gut dysbiosis and hyperplasia in a novel pig model of pediatric NASH.
Abstract: To investigate the role of bile acids (BAs) in the pathogenesis of diet-induced nonalcoholic steatohepatitis (NASH), we fed a "Western-style diet" [high fructose, high fat (HFF)] enriched with fructose, cholesterol, and saturated fat for 10 wk to juvenile Iberian pigs. We also supplemented probiotics with in vitro BA deconjugating activity to evaluate their potential therapeutic effect in NASH. Liver lipid and function, cytokines, and hormones were analyzed using commercially available kits. Metabolites, BAs, and fatty acids were measured by liquid chromatography-mass spectrometry. Histology and gene and protein expression analyses were performed using standard protocols. HFF-fed pigs developed NASH, cholestasis, and impaired enterohepatic Farnesoid-X receptor (FXR)-fibroblast growth factor 19 (FGF19) signaling in the absence of obesity and insulin resistance. Choline depletion in HFF livers was associated with decreased lipoprotein and cholesterol in serum and an increase of choline-containing phospholipids in colon contents and trimethylamine-N-oxide in the liver. Additionally, gut dysbiosis and hyperplasia increased with the severity of NASH, and were correlated with increased colonic levels of choline metabolites and secondary BAs. Supplementation of probiotics in the HFF diet enhanced NASH, inhibited hepatic autophagy, increased excretion of taurine and choline, and decreased gut microbial diversity. In conclusion, dysregulation of BA homeostasis was associated with injury and choline depletion in the liver, as well as increased biliary secretion, gut metabolism and excretion of choline-based phospholipids. Choline depletion limited lipoprotein synthesis, resulting in hepatic steatosis, whereas secondary BAs and choline-containing phospholipids in colon may have promoted dysbiosis, hyperplasia, and trimethylamine synthesis, causing further damage to the liver.NEW & NOTEWORTHY Impaired Farnesoid-X receptor (FXR)-fibroblast growth factor 19 (FGF19) signaling and cholestasis has been described in nonalcoholic fatty liver disease (NAFLD) patients. However, therapeutic interventions with FXR agonists have produced contradictory results. In a swine model of pediatric nonalcoholic steatohepatitis (NASH), we show that the uncoupling of intestinal FXR-FGF19 signaling and a decrease in FGF19 levels are associated with a choline-deficient phenotype of NASH and increased choline excretion in the gut, with the subsequent dysbiosis, colonic hyperplasia, and accumulation of trimethylamine-N-oxide in the liver.
DOI: 10.1152/ajpgi.00344.2019

Strategy ID Therapy Strategy Synonyms Therapy Targets Therapy Drugs
S01 Improve insulin resistance insulin sensitizer; insulin resistance; glucose tolerance Biguanide: increases 5-AMP activated protein kinase signaling; SGLT-2 inhibitor; Thiazalidinedione: selective PPAR-γ agonists; GLP-1 agonist Metformin; Empagliflozin; Canagliflozin; Rosiglitazone; Pioglitazone; Liraglutide Details
S13 Anti-apoptosis hepatocyte apoptosis; hepatic autophagy; apoptosis Pan-caspase inhibitor Emricasan Details

Target ID Target Name GENE Action Class UniProtKB ID Entry Name
T17 Farnesoid X-activated receptor NR1H4 agonist Nuclear hormone receptor Q96RI1 NR1H4_HUMAN Details
T18 Acetyl-CoA carboxylase 1 ACACA inhibitor Enzyme Q13085 ACACA_HUMAN Details
T29 Fibroblast growth factor 19 FGF19 variant Secreted O95750 FGF19_HUMAN Details
T07 Bile acid receptor NR1H4 agonist Nuclear hormone receptor Q96RI1 NR1H4_HUMAN Details

Diseases ID DO ID Disease Name Definition Class
I05 9352 Type 2 diabetes mellitus A diabetes that is characterized by chronic hyperglycaemia with disturbances of carbohydrate, fat and protein metabolism resulting from defects in insulin secretion, insulin action, or both. A diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. http://en.wikipedia.org/wiki/Diabetes, http://en.wikipedia.org/wiki/Diabetes_mellitus_type_2 disease of metabolism/inherited metabolic disorder/ carbohydrate metabolic disorder/glucose metabolism disease/diabetes/ diabetes mellitus Details
I14 9970 Obesity An overnutrition that is characterized by excess body fat, traditionally defined as an elevated ratio of weight to height (specifically 30 kilograms per meter squared), has_material_basis_in a multifactorial etiology related to excess nutrition intake, decreased caloric utilization, and genetic susceptibility, and possibly medications and certain disorders of metabolism, endocrine function, and mental illness. https://en.wikipedia.org/wiki/Obesity disease of metabolism/acquired metabolic disease/ nutrition disease/overnutrition Details

Drug ID Drug Name Type DrugBank ID Targets Category Latest Progress
D258 Omega 3 PUFA Chemical drug DB11133 PPARG ligand; PPARA activator Hypolipidemic drug Under clinical trials Details
D328 Serine Chemical drug DB00133 SRR Improve insulin resistance Under clinical trials Details
D075 Choline Supplement DB00122 PLD2 product of; PLD1 product of -- Under clinical trials Details
D142 Fructose Chemical drug DB04173 -- Intravenous nutrition drug Under clinical trials Details
D182 Insulin Biological drug DB00030 INSR agonist; CPE modulator&product of -- Under clinical trials Details
D284 Probiotic Supplement -- -- -- Under clinical trials Details
D125 Epanova Chemical drug DB11133 PPARG ligand; PPARA activator Enhance lipid metabolism Under clinical trials Details
D094 Cysteamine Chemical drug DB00847 GSS stimulant Renal drug Under clinical trials Details
D095 Cysteamine bitartrate Chemical drug DB00847 -- -- Under clinical trials Details