Prevention of high-fat diet-induced muscular lipid accumulation in rats by α lipoic acid is not mediated by AMPK activation

• DOI: 10.1194/jlr.m000992
• Publication Date: 2009-08-19T04:29:19Z
• Authors: Silvie Timmers; Johan de Vogel-va...; Mhairi C. Towler; Gert Schaart; Esther Moonen-Kor...; Ronald P. Mensink; Matthijs K. Hesse...; D. Grahame Hardie; Patrick Schrauwen
• Keywords: AMP-Activated Protein Kinase

Skeletal muscle triglyceride accumulation is associated with insulin resistance in obesity. Recently, it has been suggested that α lipoic acid (ALA) improves sensitivity by lowering nonadipose tissues via activation of skeletal AMP-activated protein kinase (AMPK). We examined whether chronic ALA supplementation prevents muscular lipid high-fat diets AMPK. In addition, we tested if was able to improve rats fed low- and (LFD, HFD). Supplementing male Wistar 0.5% for 8 weeks significantly reduced body weight, both on LFD HFD (−24% LFD+ALA vs. LFD, P < 0.01, −29% HFD+ALA HFD, 0.001). Oil red O staining revealed a 3-fold higher content after compared ALA-supplemented groups (P 0.05). improved whole glucose tolerance (∼20% lower total area under the curve (AUC) supplemented controls, These effects were not mediated increased AMPK or ALA-induced improvement sensitivity. To conclude, prevention HFD-induced are likely secondary due anorexic nature ALA. 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