Intracellular Lipid Accumulation in Liver and Muscle and the Insulin Resistance Syndrome

Department of Nutrition Sciences, University of Alabama at Birmingham, 1675 University Boulevard,Birmingham, AL 35294-3360, USA.
Endocrinology and metabolism clinics of North America (Impact Factor: 3.4). 01/2009; 37(4):841-56. DOI: 10.1016/j.ecl.2008.09.002
Source: PubMed


This article emphasizes intrahepatocellular and intramyocellular lipid accumulation as components of the insulin resistance syndrome. It examines the mechanisms responsible for the interrelationships among ectopic fat deposition, insulin resistance, and associated metabolic traits. These relationships are complex and vary according to diet, exercise, weight loss, and racial identity. Overall, there is a high degree of association of both intrahepatocellular and intramyocellular lipids with insulin resistance and associated cardiometabolic risk factors. It concludes that further research is necessary to determine the orchestrated roles of adipose and nonadipose tissue compartments in the regulation of insulin sensitivity, and mechanisms explaining racial differences in the insulin resistance syndrome-trait cluster.

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    • "The latter is also known as ectopic lipid accumulation and may be linked to insulin resistance and í µí»½ cell dysfunction [4] [5]. In the skeletal muscle and liver, fat deposition has been associated with the development of insulin resistance [6] [7]. In the pancreatic islets, FFA and triglycerides accumulation induce í µí»½ cell functional impairment and lipoapoptosis [8]. "
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