Dietary fish oil augments nitric oxide production or release in patients with type 2 (non-insulin-dependent) diabetes mellitus.
Decreased release of nitric oxide from damaged endothelium is responsible for the impaired endothelium-dependent vasodilator responses found in animal models of vascular disease. Dietary supplementation with fish oils has been shown to augment endothelium-dependent relaxations, principally by improving the release of nitric oxide from injured endothelium. Using forearm venous occlusion plethysmography we studied vascular responses to 60, 120, 180 and 240 nmol/min of acetylcholine (an endothelium-dependent vasodilator) and 3, 6 and 9 nmol/min of glyceryl trinitrate (an endothelium-independent vasodilator) infused into the brachial artery in 23 patients with Type 2 (non-insulin-dependent) diabetes mellitus. NG monomethyl-L-arginine was employed to inhibit stimulated and basal release of nitric oxide from the endothelium. On completion of the baseline studies patients randomly received either fish oil or matching olive oil capsules in a double-blind crossover fashion for 6 weeks followed by a 6-week washout period and a final 6-week treatment phase. Studies, identical to the initial baseline studies, were performed at the end of the active treatment periods at 6 and 18 weeks. Fish oil supplementation significantly improved forearm blood flow responses to each dose of acetylcholine when compared to the vasodilator responses recorded at baseline and after olive oil administration (p < 0.01). Neither fish oil nor olive oil supplementation produced any significant changes in forearm blood flow to the incremental infusions of glyceryl trinitrate when compared with responses recorded during the baseline studies.(ABSTRACT TRUNCATED AT 250 WORDS)
McVeigh
G E
GE
Department of Therapeutics and Pharmacology, Queen's University of Belfast, Northern Ireland.
Brennan
G M
GM
Johnston
G D
GD
McDermott
B J
BJ
McGrath
L T
LT
Henry
W R
WR
Andrews
J W
JW
Hayes
J R
JR
D000109:Acetylcholine / Q000494:pharmacology*; D016718:Arachidonic Acid / Q000097:blood; D001120:Arginine / Q000031:analogs & derivatives* / Q000494:pharmacology; D001786:Blood Glucose / Q000378:metabolism*; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000503:physiopathology*; D004041:Dietary Fats / Q000494:pharmacology*; D004281:Docosahexaenoic Acids / Q000097:blood; D004311:Double-Blind Method; D015118:Eicosapentaenoic Acid / Q000097:blood; D005260:Female; D005395:Fish Oils / Q000494:pharmacology*; D005542:Forearm / Q000098:blood supply; D006442:Glycated Hemoglobin / Q000032:analysis; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008297:Male; D008563:Membrane Lipids / Q000097:blood*; D008875:Middle Aged; D009569:Nitric Oxide / Q000378:metabolism*; D000069463:Olive Oil; D010938:Plant Oils / Q000494:pharmacology*; D014280:Triglycerides / Q000097:blood; D014655:Vascular Resistance / Q000187:drug effects; D019323:omega-N-Methylarginine
D000109:Acetylcholine; D016718:Arachidonic Acid; D001120:Arginine; D001786:Blood Glucose; D002784:Cholesterol; D004041:Dietary Fats; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid; D005395:Fish Oils; D006442:Glycated Hemoglobin; D008563:Membrane Lipids; D009569:Nitric Oxide; D000069463:Olive Oil; D010938:Plant Oils; D014280:Triglycerides; D019323:omega-N-Methylarginine