The role of plasma non-esterified fatty acids during exercise in type 2 diabetes mellitus.
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.(ABSTRACT TRUNCATED AT 250 WORDS)
Berrish
T S
TS
Department of Medicine, University of Newcastle upon Tyne, UK.
Elliott
C
C
Cooper
B G
BG
Reed
J W
JW
Orskov
H
H
Alberti
K G
KG
Walker
M
M
D020155:3-Hydroxybutyric Acid; D001786:Blood Glucose / Q000378:metabolism; D002096:C-Peptide / Q000097:blood; D002151:Calorimetry; D002245:Carbon Dioxide / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000503:physiopathology / Q000652:urine; D004734:Energy Metabolism / Q000187:drug effects; D015444:Exercise; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D005934:Glucagon / Q000097:blood; D005990:Glycerol / Q000097:blood; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D006885:Hydroxybutyrates / Q000097:blood; D000960:Hypolipidemic Agents / Q000494:pharmacology*; D007328:Insulin / Q000097:blood; D007773:Lactates / Q000097:blood; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000652:urine; D010101:Oxygen Consumption / Q000187:drug effects; D011719:Pyrazines / Q000494:pharmacology*; D012016:Reference Values
D001786:Blood Glucose; D002096:C-Peptide; D005230:Fatty Acids, Nonesterified; D006885:Hydroxybutyrates; D000960:Hypolipidemic Agents; D007328:Insulin; D007773:Lactates; D011719:Pyrazines; D002245:Carbon Dioxide; D013006:Growth Hormone; D005934:Glucagon; C027696:acipimox; D009584:Nitrogen; D005990:Glycerol; D020155:3-Hydroxybutyric Acid