Exercise training improves vascular endothelial function in patients with type 1 diabetes.
OBJECTIVE-Impaired endothelial function of resistance and conduit arteries can be detected in patients with type 1 diabetes. We studied whether a persistent improvement of endothelial function can be achieved by regular physical training. RESEARCH DESIGN AND METHODS-The study included 26 patients with type 1 diabetes of 20 +/- 10 years' duration and no overt angiopathy; 18 patients (42 +/- 10 years old) participated in a bicycle exercise training program, and 8 patients with type 1 diabetes (33 +/- 11 years old) served as control subjects. Vascular function of conduit arteries was assessed by flow-mediated and endothelium-independent dilation of the brachial artery and of resistance vessels by the response of ocular fundus pulsation amplitudes to intravenous N(G)-monomethyl-L-arginine (L-NMMA) at baseline, after 2 and 4 months of training, and 8 months after cessation of regular exercise. RESULTS-Training increased peak oxygen uptake (VO(2max)) by 13% after 2 months and by 27% after 4 months (P = 0.04). Flow-mediated dilation (FMD) of the brachial artery increased from 6.5 +/- 1.1 to 9.8 +/- 1.1% (P = 0.04) by training. L-NMMA administration decreased fundus pulsation amplitude (FPA) by 9.1 +/- 0.9% before training and by 13.4 +/- 1.5% after 4 months of training (P = 0.02). VO(2max), FMD, and FPA were unchanged in the control group. Vascular effects from training were abrogated 8 months after cessation of exercise. CONCLUSIONS-Our study demonstrates that aerobic exercise training can improve endothelial function in different vascular beds in patients with long-standing type 1 diabetes, who are at considerable risk for diabetic angiopathy. However, the beneficial effect on vascular function is not maintained in the absence of exercise.
D000328:Adult; D001916:Brachial Artery / Q000187:drug effects / Q000503:physiopathology*; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology* / Q000628:therapy; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D015444:Exercise / Q000502:physiology*; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D007537:Isometric Contraction; D008019:Life Style; D008297:Male; D010101:Oxygen Consumption / Q000502:physiology*; D011674:Pulse; D016896:Treatment Outcome; D014664:Vasodilation / Q000502:physiology; D019323:omega-N-Methylarginine / Q000494:pharmacology
D019323:omega-N-Methylarginine