Mechanisms of Disease: hepatic steatosis in type 2 diabetes--pathogenesis and clinical relevance
- PMID: 16932311
- DOI: 10.1038/ncpendmet0190
Mechanisms of Disease: hepatic steatosis in type 2 diabetes--pathogenesis and clinical relevance
Abstract
Hepatic steatosis is defined by an increased content of hepatocellular lipids (HCLs) and is frequently observed in insulin-resistant states including type 2 diabetes mellitus. A dietary excess of saturated fat contributes significantly to HCL accumulation. Elevated HCL levels mainly account for hepatic insulin resistance, which is probably mediated by partitioning of free fatty acids to the liver (fat overflow) and by an imbalance of adipocytokines (decreased adiponectin and/or increased proinflammatory cytokines). Both free fatty acids and adipocytokines activate inflammatory pathways that include protein kinase C, the transcription factor nuclear factor kappaB, and c-Jun N-terminal kinase 1 and can thereby accelerate the progression of hepatic steatosis to nonalcoholic steatohepatitis and cirrhosis. Proton magnetic resonance spectroscopy has made it possible to quantify HCL concentrations and to detect even small changes in these concentrations in clinical settings. Moderately hypocaloric, fat-reduced diets can decrease HCL levels by approximately 40-80% in parallel with loss of up to 8% of body weight. Treatment with thiazolidinediones (e.g. pioglitazone and rosiglitazone) reduces HCL levels by 30-50% by modulating insulin sensitivity and endocrine function of adipose tissue in type 2 diabetes. Metformin improves hepatic insulin action without affecting HCL levels, whereas insulin infusion for 67 h increases HCL levels by approximately 18%; furthermore, HCL levels positively correlate with the insulin dosage in insulin-treated type 2 diabetes. In conclusion, liver fat is a critical determinant of metabolic fluxes and inflammatory processes, thereby representing an important therapeutic target in insulin resistance and type 2 diabetes mellitus.
Similar articles
-
Thiazolidinediones and the liver in humans.Curr Opin Lipidol. 2009 Dec;20(6):477-83. doi: 10.1097/MOL.0b013e3283321d37. Curr Opin Lipidol. 2009. PMID: 19779336 Review.
-
Hepatic dysfunction and insulin insensitivity in type 2 diabetes mellitus: a critical target for insulin-sensitizing agents.Diabetes Obes Metab. 2008 Sep;10(9):699-718. doi: 10.1111/j.1463-1326.2007.00761.x. Epub 2007 Sep 6. Diabetes Obes Metab. 2008. PMID: 17825080 Review.
-
Insulin resistance accelerates a dietary rat model of nonalcoholic steatohepatitis.Gastroenterology. 2007 Jan;132(1):282-93. doi: 10.1053/j.gastro.2006.10.014. Epub 2006 Oct 12. Gastroenterology. 2007. PMID: 17241878
-
Effects of pioglitazone and metformin on intracellular lipid content in liver and skeletal muscle of individuals with type 2 diabetes mellitus.Metabolism. 2007 Oct;56(10):1418-24. doi: 10.1016/j.metabol.2007.06.005. Metabolism. 2007. PMID: 17884455
-
Hepatitis C, insulin resistance and diabetes: clinical and pathogenic data.Liver Int. 2009 Mar;29 Suppl 2:13-25. doi: 10.1111/j.1478-3231.2008.01952.x. Liver Int. 2009. PMID: 19187069 Review.
Cited by
-
Circulating lysophosphatidylcholines are markers of a metabolically benign nonalcoholic fatty liver.Diabetes Care. 2013 Aug;36(8):2331-8. doi: 10.2337/dc12-1760. Epub 2013 Mar 20. Diabetes Care. 2013. PMID: 23514731 Free PMC article.
-
Molecular and immunohistochemical effects of metformin in a rat model of type 2 diabetes mellitus.Exp Ther Med. 2015 May;9(5):1921-1930. doi: 10.3892/etm.2015.2354. Epub 2015 Mar 13. Exp Ther Med. 2015. PMID: 26136915 Free PMC article.
-
Regulation of type 2 diabetes by helminth-induced Th2 immune response.J Vet Med Sci. 2017 Jan 10;78(12):1855-1864. doi: 10.1292/jvms.16-0183. Epub 2016 Sep 22. J Vet Med Sci. 2017. PMID: 27665994 Free PMC article.
-
Daily Treatment of Mice with Type 2 Diabetes with Adropin for Four Weeks Improves Glucolipid Profile, Reduces Hepatic Lipid Content and Restores Elevated Hepatic Enzymes in Serum.Int J Mol Sci. 2022 Aug 29;23(17):9807. doi: 10.3390/ijms23179807. Int J Mol Sci. 2022. PMID: 36077198 Free PMC article.
-
G-quadruplex forming regions in GCK and TM6SF2 are targets for differential DNA methylation in metabolic disease and hepatocellular carcinoma patients.Sci Rep. 2024 Aug 30;14(1):20215. doi: 10.1038/s41598-024-70749-0. Sci Rep. 2024. PMID: 39215018 Free PMC article.
Publication types
MeSH terms
Substances
LinkOut - more resources
Medical
Research Materials
Miscellaneous