Research Article Details
Article ID: | A24922 |
PMID: | 22359625 |
Source: | PLoS One |
Title: | Liver and muscle in morbid obesity: the interplay of fatty liver and insulin resistance. |
Abstract: | INTRODUCTION: Nonalcoholic fatty liver disease (NAFLD) can be seen as a manifestation of overnutrition. The muscle is a central player in the adaptation to energy overload, and there is an association between fatty-muscle and -liver. We aimed to correlate muscle morphology, mitochondrial function and insulin signaling with NAFLD severity in morbid obese patients. METHODS: Liver and deltoid muscle biopsies were collected during bariatric surgery in NAFLD patients. NAFLD Activity Score and Younossi's classification for nonalcoholic steatohepatitis (NASH) were applied to liver histology. Muscle evaluation included morphology studies, respiratory chain complex I to IV enzyme assays, and analysis of the insulin signaling cascade. A healthy lean control group was included for muscle morphology and mitochondrial function analyses. RESULTS: Fifty one NAFLD patients were included of whom 43% had NASH. Intramyocellular lipids (IMCL) were associated with the presence of NASH (OR 12.5, p<0.001), progressive hepatic inflammation (p = 0.029) and fibrosis severity (p = 0.010). There was a trend to an association between IMCL and decreased Akt phosphorylation (p = 0.059), despite no association with insulin resistance. In turn, hepatic steatosis (p = 0.015) and inflammation (p = 0.013) were associated with decreased Akt phosphoryation. Citrate synthase activity was lower in obese patients (p = 0.047) whereas complex I (p = 0.040) and III (p = 0.036) activities were higher, compared with controls. Finally, in obese patients, complex I activity increased with progressive steatosis (p = 0.049) and with a trend with fibrosis severity (p = 0.056). CONCLUSIONS: In morbid obese patients, presence of IMCL associates with NASH and advanced fibrosis. Muscle mitochondrial dysfunction does not appear to be a major driving force contributing to muscle fat accumulation, insulin resistance or liver disease. Importantly, insulin resistance in muscle might occur at a late point in the insulin signaling cascade and be associated with IMCL and NAFLD severity. |
DOI: | 10.1371/journal.pone.0031738 |

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 |
S09 | Bariatric surgery | Metabolic surgery | -- | -- | 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 | |
---|---|---|---|---|---|---|---|
D080 | Citrulline | Chemical drug | DB00155 | -- | -- | Under clinical trials | Details |
D545 | Pig placenta extract | Biological extract | -- | -- | -- | Under clinical trials | Details |
D083 | CLA | Chemical drug | DB01211 | KCNH2; SLCO1B1; SLCO1B3 | -- | Under clinical trials | Details |
D182 | Insulin | Biological drug | DB00030 | INSR agonist; CPE modulator&product of | -- | Under clinical trials | Details |