Research Article Details
Article ID: | A43657 |
PMID: | 31168510 |
Source: | Hepatol Commun |
Title: | Protective Function of Mitogen-Activated Protein Kinase Phosphatase 5 in Aging- and Diet-Induced Hepatic Steatosis and Steatohepatitis. |
Abstract: | Nonalcoholic fatty liver disease is currently the most common liver disease and is a leading cause of liver-related morbidity and mortality. However, its pathogenesis remains largely unclear. We previously showed that mice deficient in mitogen-activated protein kinase (MAPK) phosphatase 5 (MKP5) spontaneously developed insulin resistance and glucose intolerance, which are associated with visceral obesity and adipose tissue inflammation. In this study, we discovered that mice deficient in MKP5 developed more severe hepatic steatosis and steatohepatitis with age or with feeding on a high-fat diet (HFD) compared to wild-type (WT) mice, and this was associated with increased expression of proinflammatory cytokines and collagen genes. Increased p38 activation in MKP5 knockout (KO) liver compared to that in WT liver was detected, which contributed to increased expression of lipid droplet-associated protein cell death-inducing DFF45-like effector A (CIDEA) and CIDEC/fat-specific protein 27 but not CIDEB through activating transcription factor 2 (ATF2). In addition, MKP5 KO liver had higher peroxisome proliferator-activated receptor gamma (PPARγ) expression compared with WT liver. On the other hand, overexpression of MKP5 or inhibition of p38 activation in hepatocytes resulted in reduced expression of PPARγ. Inhibition of p38 resulted in alleviation of hepatic steatosis in KO liver in response to HFD feeding, and this was associated with reduced expression of CIDEA, CIDEC, and proinflammatory cytokines. Conclusion: MKP5 prevents the development of nonalcoholic steatohepatitis by suppressing p38-ATF2 and p38-PPARγ to reduce hepatic lipid accumulation, inflammation, and fibrosis. |
DOI: | 10.1002/hep4.1324 |

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 |
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 |
S05 | Anti-inflammatory | inflammatory | Bile acid; TNF-a inhibitor; Dual PPAR-α and -δ agonists; Toll-Like Receptor; (TLR)-4 antagonist; Caspase inhibitor; ASK-1 inhibitor | Ursodeoxycholic Acid; Pentoxifylline; Elafibranor; JKB-121; Emricasan; Selonsertib; | 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 |
T05 | Peroxisome proliferator-activated receptor gamma | PPARG | agonist | Nuclear hormone receptor | P37231 | PPARG_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 |