BACKGROUND: Lipoic acid (LA) is an antioxidant with antiobesity and antidiabetic properties. Adiponectin is an adipokine with potent anti-inflammatory and insulin-sensitizing properties. AMP-activated protein kinase (AMPK) is a key enzyme involved in cellular energy homeostasis. Activation of AMPK has been considered as a target to reverse the metabolic abnormalities associated with obesity and type 2 diabetes. AIM OF THE STUDY: The aim of this study was to determine the effects of LA on AMPK phosphorylation and adiponectin production in adipose tissue of low-fat (control diet) and high-fat diet-fed rats. RESULTS: Dietary supplementation with LA reduced body weight and adiposity in control and high-fat-fed rats. LA also reduced basal hyperinsulinemia as well as the homeostasis model assessment (HOMA) levels, an index of insulin resistance, in high-fat-fed rats, which was in part independent of their food intake lowering actions. Furthermore, AMPK phosphorylation was increased in white adipose tissue (WAT) from LA-treated rats as compared with pair-fed animals. Dietary supplementation with LA also upregulated adiponectin gene expression in WAT, while a negative correlation between adiposity-corrected adiponectin levels and HOMA index was found. Our present data suggest that the ability of LA supplementation to prevent insulin resistance in high-fat diet-fed rats might be related in part to the stimulation of AMPK and adiponectin in WAT.
BACKGROUND:Lipoic acid (LA) is an antioxidant with antiobesity and antidiabetic properties. Adiponectin is an adipokine with potent anti-inflammatory and insulin-sensitizing properties. AMP-activated protein kinase (AMPK) is a key enzyme involved in cellular energy homeostasis. Activation of AMPK has been considered as a target to reverse the metabolic abnormalities associated with obesity and type 2 diabetes. AIM OF THE STUDY: The aim of this study was to determine the effects of LA on AMPK phosphorylation and adiponectin production in adipose tissue of low-fat (control diet) and high-fat diet-fed rats. RESULTS: Dietary supplementation with LA reduced body weight and adiposity in control and high-fat-fed rats. LA also reduced basal hyperinsulinemia as well as the homeostasis model assessment (HOMA) levels, an index of insulin resistance, in high-fat-fed rats, which was in part independent of their food intake lowering actions. Furthermore, AMPK phosphorylation was increased in white adipose tissue (WAT) from LA-treated rats as compared with pair-fed animals. Dietary supplementation with LA also upregulated adiponectin gene expression in WAT, while a negative correlation between adiposity-corrected adiponectin levels and HOMA index was found. Our present data suggest that the ability of LA supplementation to prevent insulin resistance in high-fat diet-fed rats might be related in part to the stimulation of AMPK and adiponectin in WAT.
Authors: E D Targonsky; F Dai; V Koshkin; G T Karaman; A V Gyulkhandanyan; Y Zhang; C B Chan; M B Wheeler Journal: Diabetologia Date: 2006-05-13 Impact factor: 10.122
Authors: Silvie Timmers; Johan de Vogel-van den Bosch; Mhairi C Towler; Gert Schaart; Esther Moonen-Kornips; Ronald P Mensink; Matthijs K Hesselink; D Grahame Hardie; Patrick Schrauwen Journal: J Lipid Res Date: 2009-08-18 Impact factor: 5.922
Authors: T Yamauchi; J Kamon; Y Minokoshi; Y Ito; H Waki; S Uchida; S Yamashita; M Noda; S Kita; K Ueki; K Eto; Y Akanuma; P Froguel; F Foufelle; P Ferre; D Carling; S Kimura; R Nagai; B B Kahn; T Kadowaki Journal: Nat Med Date: 2002-10-07 Impact factor: 53.440
Authors: A E Huerta; P L Prieto-Hontoria; M Fernández-Galilea; N Sáinz; M Cuervo; J A Martínez; M J Moreno-Aliaga Journal: J Physiol Biochem Date: 2015-03-28 Impact factor: 4.158