Research Article Details
| Article ID: | A18281 |
| PMID: | 27245430 |
| Source: | J Hepatol |
| Title: | Hepatocyte vitamin D receptor regulates lipid metabolism and mediates experimental diet-induced steatosis. |
| Abstract: | BACKGROUND & AIMS: The pathogenesis and progression of non-alcoholic fatty liver disease (NAFLD) is still incompletely understood. Several nuclear receptors play a role in liver lipid metabolism and can promote hepatosteatosis, but the possible role of vitamin D receptor (VDR) in NAFLD has not been investigated. METHODS: The expression of liver VDR was investigated in apolipoprotein E knockout (apoE(-/-)) mice on a high fat diet, in wild-type mice on methionine and choline deficient diet and in NAFLD patients with hepatosteatosis and non-alcoholic steatohepatitis. The relevance of VDR was assessed in apoE(-/-) mice by deletion of VDR or paricalcitol treatment and in human HepG2 cells by VDR transfection or silencing. The role of VDR in fibrosis was also determined in VDR knockout mice (VDR(-/-)) treated with thioacetamide. RESULTS: Expression of liver VDR was markedly induced in two mouse models of NAFLD, as well as in patients with hepatosteatosis, but decreased in non-alcoholic steatohepatitis. VDR deletion in high fat diet-fed apoE(-/-) mice protected against fatty liver, dyslipidemia and insulin resistance, and caused a decrease in taurine-conjugated bile acids, but did not influence fibrosis by thioacetamide. apoE(-/-)VDR(-/-) mouse livers showed decreased gene expression of CD36, DGAT2, C/EBPα and FGF21, and increased expression of PNPLA2, LIPIN1 and PGC1α. Treatment of apoE(-/-) mice on high fat diet with paricalcitol had modest opposite effects on steatosis and gene expression. Finally, this set of genes showed concordant responses when VDR was overexpressed or silenced in HepG2 cells. CONCLUSIONS: Induced hepatocyte VDR in NAFLD regulates key hepatic lipid metabolism genes and promotes high fat diet-associated liver steatosis. Therapeutic inhibition of liver VDR may reverse steatosis in early NAFLD. LAY SUMMARY: The amount of vitamin D receptor is induced early in the livers of mice and humans when they develop non-alcoholic fatty liver disease. If the gene for the vitamin D receptor is deleted, hepatic lipid metabolism changes and mice do not accumulate fat in the liver. We conclude that the vitamin D receptor can contribute to the fatty liver disease promoted by a high fat diet. |
| DOI: | 10.1016/j.jhep.2016.05.031 |
| 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 |
| S02 | Enhance lipid metabolism | triglyceride-lowering; lipid tolerance; lipid metabolism | 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) inhibitor; Decreases intestinal cholesterol absorption; FXR agonist; ACC inhibitor; FAS inhibitor; DGAT2 inhibitor; SCD-1 inhibitor | Atorvastatin; Ezetimibe; Obeticholic Acid; GS-9674; GS-0976; TVB-2640; IONIS-DGAT2rx; Aramchol; | Details |
| S03 | Anti-fibrosis | fibrosis | Angiotensin Receptor Blocker (ARB); CCR2/CCR5 antagonist; Thyroid receptor β agonist; PEGylated human FGF21 analogue; Monoclonal antibody to lysyl oxidase-like 2 (LOXL2); Galectin-3 inhibitor; FGF19 variant | Losartan; Cenicriviroc; VK-2809; MGL-3196; Pegbelfermin; Simtuzumab; GR-MD-02; NGM282 | Details |
| Target ID | Target Name | GENE | Action | Class | UniProtKB ID | Entry Name | |
|---|---|---|---|---|---|---|---|
| T10 | Caspase-1 | CASP1 | inhibitor | Enzyme | P29466 | CASP1_HUMAN | Details |
| T18 | Acetyl-CoA carboxylase 1 | ACACA | inhibitor | Enzyme | Q13085 | ACACA_HUMAN | Details |
| T28 | Fibroblast growth factor 21 | FGF21 | analogue | Secreted | Q9NSA1 | FGF21_HUMAN | Details |
| T21 | Diacylglycerol O-acyltransferase 2 | DGAT2 | inhibitor | Enzyme | Q96PD7 | DGAT2_HUMAN | Details |
| Diseases ID | DO ID | Disease Name | Definition | Class | |
|---|---|---|---|---|---|
| I13 | 3146 | Lipid metabolism disorder | An inherited metabolic disorder that involves the creation and degradation of lipids. http://en.wikipedia.org/wiki/Lipid_metabolism | disease of metabolism/ inherited metabolic disorder | Details |
| 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 |
| Drug ID | Drug Name | Type | DrugBank ID | Targets | Category | Latest Progress | |
|---|---|---|---|---|---|---|---|
| D387 | Vitamin D | Supplement | DB11094 | -- | Vitamin source drug | Under clinical trials | Details |
| D075 | Choline | Supplement | DB00122 | PLD2 product of; PLD1 product of | -- | Under clinical trials | Details |
| D080 | Citrulline | Chemical drug | DB00155 | -- | -- | Under clinical trials | Details |
| D182 | Insulin | Biological drug | DB00030 | INSR agonist; CPE modulator&product of | -- | Under clinical trials | Details |
| D054 | Calcitriol | Supplement | DB00136 | -- | -- | Under clinical trials | Details |