title: Effect of α-lipoic acid and exercise training on cardiovascular disease risk in obesity with impaired glucose tolerance.
abstract: Obese subjects with impaired glucose tolerance (IGT) are more susceptible than healthy individuals to oxidative stress and cardiovascular disease. This randomised controlled investigation was designed to test the hypothesis that α-lipoic acid supplementation and exercise training may elicit favourable clinical changes in obese subjects with IGT. All data were collected from 24 obese (BMI ≥ 30 kg/m2) IGT patients. Following participant randomisation into two groups, fasting venous blood samples were obtained at baseline, and before and following intervention. The first group consisted of 12 participants who completed a 12 week control phase followed by 12 weeks of chronic exercise at 65% HRmax for 30 minutes a day, 5 days per week, while ingesting 1 gram per day of α-lipoic acid for 12 weeks. The second group consisted of 12 participants who completed the same 12 week control phase, but this was followed by 12 weeks of 1 gram per day of α-lipoic acid supplementation only (no exercise). The main findings show a comparatively greater rate of low density lipoprotein (LDL) oxidation in the group consisting of α-lipoic acid only (p < 0.05 vs. pre intervention), although total oxidant status was lower post intervention (p < 0.05 vs. baseline) in this group. However, exercise and α-lipoic acid in combination attenuates LDL oxidation. Furthermore, in the α-lipoic acid supplement plus exercise training group, total antioxidant capacity was significantly increased (p < 0.05 vs. baseline and pre intervention). Body fat percentage and waist and hip circumference decreased following exercise training (p < 0.05 vs. post intervention). There were no selective treatment differences for a range of other clinical outcomes including glycaemic regulation (p > 0.05). These findings report that α-lipoic acid ingestion may increase the atherogenicity of LDL when ingested in isolation of exercise, suggesting that in IGT the use of this antioxidant treatment does not ameliorate metabolic disturbances, but instead may detrimentally contribute to the pathogenesis of atherosclerosis and development of CVD. However, when α-lipoic acid is combined with exercise, this atherogenic effect is abolished.
authors: Sport and Exercise Sciences Research Institute, University of Ulster, Jordanstown, BT37 OQB, UK.
authors: Andrea M
authors: AM
authors: McNeilly
authors: Gareth W
authors: GW
authors: Davison
authors: Marie H
authors: MH
authors: Murphy
authors: Nida
authors: N
authors: Nadeem
authors: Tom
authors: T
authors: Trinick
authors: Ellie
authors: E
authors: Duly
authors: Anna
authors: A
authors: Novials
authors: Jane
authors: J
authors: McEneny
mesh_terms: D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use*; D001786:Blood Glucose; D001823:Body Composition / Q000187:drug effects; D002318:Cardiovascular Diseases / Q000209:etiology / Q000517:prevention & control*; D002149:Energy Intake; D005081:Exercise Therapy; D005260:Female; D044882:Glucose Metabolism Disorders / Q000150:complications / Q000628:therapy*; D006442:Glycated Hemoglobin / Q000378:metabolism; D006439:Hemodynamics; D006801:Humans; D008074:Lipoproteins / Q000378:metabolism; D008077:Lipoproteins, LDL / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000628:therapy*; D010084:Oxidation-Reduction; D012307:Risk Factors; D008063:Thioctic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000975:Antioxidants; D001786:Blood Glucose; D006442:Glycated Hemoglobin; D008074:Lipoproteins; D008077:Lipoproteins, LDL; D008063:Thioctic Acid; C099252:oxidized low density lipoprotein