The role of plasma non-esterified fatty acids during exercise in type 2 diabetes mellitus

• Published in: Diabetic medicine Vol. 10; no. 2; p. 152
• Main Authors: Berrish, T S, Elliott, C, Cooper, B G, Reed, J W, Orskov, H, Alberti, K G, Walker, M
• Format: Journal Article
• Language: English
• Published: England 01.03.1993
• Subjects: 3-Hydroxybutyric Acid; Blood Glucose - metabolism; C-Peptide - blood; Calorimetry; Carbon Dioxide - analysis; Diabetes Mellitus, Type 2 - blood; Diabetes Mellitus, Type 2 - physiopathology; Diabetes Mellitus, Type 2 - urine; Energy Metabolism - drug effects; Exercise; Fatty Acids, Nonesterified - blood; Female; Glucagon - blood; Glycerol - blood; Growth Hormone - blood; Humans; Hydroxybutyrates - blood; Hypolipidemic Agents - pharmacology; Insulin - blood; Lactates - blood; Male; Middle Aged; Nitrogen - urine; Oxygen Consumption - drug effects; Pyrazines - pharmacology; Reference Values
• ISSN: 0742-3071
• DOI: 10.1111/j.1464-5491.1993.tb00033.x

Elevated fasting plasma non-esterified fatty acid (NEFA) levels have been reported in Type 2 diabetes. We examined whether such changes persist during low-grade exercise and influence carbohydrate metabolism. Eight Type 2 diabetic patients with moderate glycaemic control and eight healthy controls received the anti-lipolytic agent, acipimox, or placebo on separate occasions before exercising for 45 min at 35% pre-determined VO2max. Fasting plasma NEFA levels were similar (0.40 +/- 0.06 (SEM) and 0.45 +/- 0.05 mmol l-1; healthy and Type 2 diabetic subjects) following placebo, and increased to comparable levels with exercise (0.73 +/- 0.07 and 0.73 +/- 0.10 mmol l-1). Acipimox lowered basal NEFA levels (0.14 +/- 0.03 and 0.28 +/- 0.04 mmol l-1; both p < 0.05 vs placebo), and prevented the rise with exercise. Blood glucose (p < 0.001) and serum insulin (p < 0.01) levels were higher in the Type 2 diabetic patients (vs controls) for both treatments. Whole body lipid oxidation increased from baseline to a comparable degree with exercise following placebo (3.2 +/- 0.3 and 2.8 +/- 0.3 mg kg-1 min-1; healthy and Type 2 diabetic subjects, both p < 0.02). Although less marked, the same was also observed following acipimox (2.0 +/- 0.4 and 2.1 +/- 0.5 mg kg-1 min-1; both p < 0.05). Carbohydrate oxidation increased with exercise in both subject groups, but with no significant difference between the treatments. Thus, the metabolic response to low-grade exercise was normal in Type 2 diabetic patients with moderate glycaemic control, but occurred against a background of hyperinsulinaemia.