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Hoeks 2010 Diabetes
Coupling states LEAK  + , OXPHOS  + , ET  +
Diseases Diabetes  +
Has abstract Type 2 diabetes and insulin resistance hav
Type 2 diabetes and insulin resistance have been associated with mitochondrial dysfunction, but it is debated whether this is a primary factor in the pathogenesis of the disease. To test the concept that mitochondrial dysfunction is secondary to the development of insulin resistance, we employed the unique model of prolonged fasting in humans. Prolonged fasting is a physiologic condition in which muscular insulin resistance develops in the presence of increased free fatty acid (FFA) levels, increased fat oxidation and low glucose and insulin levels. It is therefore anticipated that skeletal muscle mitochondrial function is maintained to accommodate increased fat oxidation unless factors secondary to insulin resistance exert negative effects on mitochondrial function. While in a respiration chamber, twelve healthy males were subjected to a 60 h fast and a 60 h normal fed condition in a randomized crossover design. Afterward, insulin sensitivity was assessed using a hyperinsulinemic-euglycemic clamp, and mitochondrial function was quantified ''ex vivo'' in permeabilized muscle fibers using high-resolution respirometry. Indeed, FFA levels were increased approximately ninefold after 60 h of fasting in healthy male subjects, leading to elevated intramuscular lipid levels and decreased muscular insulin sensitivity. Despite an increase in whole-body fat oxidation, we observed an overall reduction in both coupled state 3 respiration and maximally uncoupled respiration in permeabilized skeletal muscle fibers, which could not be explained by changes in mitochondrial density. These findings confirm that the insulin-resistant state has secondary negative effects on mitochondrial function. Given the low insulin and glucose levels after prolonged fasting, hyperglycemia and insulin action per se can be excluded as underlying mechanisms, pointing toward elevated plasma FFA and/or intramuscular fat accumulation as possible causes for the observed reduction in mitochondrial capacity.
erved reduction in mitochondrial capacity.  +
Has info [http://www.ncbi.nlm.nih.gov/pubmed/20573749 PMID: 20573749 Open Access]  +
Has title Hoeks J, van Herpen NA, Mensink M, Moonen-Kornips E, van Beurden D, Hesselink MK, Schrauwen P (2010) Prolonged fasting identifies skeletal muscle mitochondrial dysfunction as consequence rather than cause of human insulin resistance. Diabetes 59:2117-25.  +
Instrument and method Oxygraph-2k  +
Mammal and model Human  +
MiP area Respiration  + , Exercise physiology;nutrition;life style  +
Pathways F  + , N  + , NS  + , Other combinations  +
Preparation Permeabilized tissue  +
Tissue and cell Skeletal muscle  +
Was published by MiPNetLab NL Maastricht Schrauwen P +
Was published in journal Diabetes +
Was published in year 2010  +
Was written by Hoeks J + , Van Herpen NA + , Mensink M + , Moonen-Kornips E + , Van Beurden D + , Hesselink MK + , Schrauwen P +
Categories Publications
Modification date
"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by Semantic MediaWiki.
12:37:53, 13 November 2017  +
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