title: Regular physical exercise normalizes elevated asymmetrical dimethylarginine concentrations in patients with type 1 diabetes mellitus.
abstract: BACKGROUND
  Levels of the endogenous nitric oxide synthase inhibitor asymmetrical dimethylarginine (ADMA) are elevated in patients with type 1 diabetes mellitus (DM1) and may contribute to vascular complications. In this study we tested the hypothesis that elevated ADMA in patients with DM1 can be reduced by regular physical exercise.
  
  
  METHODS
  Plasma samples for analysis of L-arginine, ADMA, symmetrical dimethylarginine (SDMA) and metabolic parameters were obtained from 11 patients with DM1 who participated in a supervised aerobic exercise program for four months. Samples were collected before the training began, at two and four months after initiation, and eight months after cessation of regular training. Fifteen age- and sex-matched healthy persons who did not exercise regularly were examined once as controls and did not participate in the training program.
  
  
  RESULTS
  The patients with DM1 had higher ADMA levels than the controls before the training program began (0.54 +/- 0.02 vs. 0.44 +/- 0.03 micromol/l; P < 0.05). After two and four months of exercise, ADMA concentrations in the patients decreased to those seen in healthy persons (0.42 +/- 0.02 and 0.43 +/- 0.03 micromol/l; P < 0.001 and P < 0.05 compared with ADMA levels before training began). Eight months after cessation of the exercise program, ADMA levels in the patients reverted to those observed before the start of training. The L-arginine-to-ADMA ratio increased slightly after two months; L-arginine, symmetrical dimethylarginine, blood lipids and HbA1c were not affected by the training program.
  
  
  CONCLUSIONS
  Elevated ADMA levels in patients with DM1, who have a high risk for developing cardiovascular disease, can be lowered to those of healthy persons by regular physical exercise. This favorable effect on ADMA is not sustained when training is discontinued.
authors.affiliation: Department of Clinical Pharmacology, Medical University Vienna, Vienna, Austria.
authors.forename: Friedrich
authors.initials: F
authors.lastname: Mittermayer
authors.forename: Johannes
authors.initials: J
authors.lastname: Pleiner
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Krzyzanowska
authors.forename: Günther F
authors.initials: GF
authors.lastname: Wiesinger
authors.forename: Mario
authors.initials: M
authors.lastname: Francesconi
authors.forename: Michael
authors.initials: M
authors.lastname: Wolzt
mesh_terms: D000328:Adult; D001120:Arginine / Q000031:analogs & derivatives* / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood* / Q000209:etiology / Q000517:prevention & control*; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications / Q000628:therapy*; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D016896:Treatment Outcome
chemical_list: C487735:dimethylarginine; D001120:Arginine