title: Effects of combined supplementation with B vitamins and antioxidants on plasma levels of asymmetric dimethylarginine (ADMA) in subjects with elevated risk for cardiovascular disease.
abstract: Elevated plasma asymmetric dimethylarginine (ADMA) concentrations have been suggested as a potential risk factor for cardiovascular disease (CVD). Studies indicate a linkage between hyperhomocysteinemia, oxidative stress and ADMA metabolism. We tested the hypothesis that combined supplementation of B vitamins and antioxidants reduces ADMA concentrations in subjects with at least two CVD risk factors. A total of 123 men and women (58+/-8.1 years) were randomly assigned to take either a preparation including B vitamins and antioxidants (verum) or placebo for 6 months in a double-blind design. Blood concentrations of ADMA, symmetric dimethylarginine (SDMA), L-arginine, B vitamins, total homocysteine (tHcy), alpha-tocopherol, antioxidant capacity (TEAC), and oxLDL were measured pre- and post-intervention. Treatment with verum significantly decreased tHcy (-2.14 micromol/L; P<0.001) and significantly increased TEAC values (+39.3 microM; P<0.022), but no effect on ADMA was observed. OxLDL was significantly reduced in verum (-7.3 U/L; P=0.001) and placebo (-9.2U/L; P<0.001). At baseline, significant correlations were found only between ADMA and SDMA (r=0.281; P=0.002), L-arginine/ADMA and SDMA (r=-0.294; P<0.001), L-arginine/ADMA and oxLDL (r=-0.281; P=0.016), and L-arginine/ADMA and age (r=-0.231; P=0.010). Our results indicate that combined supplementation of B vitamins and antioxidants is not an adequate strategy to reduce ADMA plasma levels in subjects with elevated CVD risk.
authors.affiliation: Nutrition Physiology and Human Nutrition Unit, Institute of Food Science, University of Hannover, Wunstorfer Str. 14, D-30453 Hannover, Germany. birgit.schmitt@lw.uni-hannover.de
authors.forename: B
authors.initials: B
authors.lastname: Schmitt
authors.forename: M
authors.initials: M
authors.lastname: Wolters
authors.forename: G
authors.initials: G
authors.lastname: Kressel
authors.forename: O
authors.initials: O
authors.lastname: Hülsmann
authors.forename: A
authors.initials: A
authors.lastname: Ströhle
authors.forename: W N
authors.initials: WN
authors.lastname: Kühn-Velten
authors.forename: R
authors.initials: R
authors.lastname: Lichtinghagen
authors.forename: A
authors.initials: A
authors.lastname: Bub
authors.forename: S W
authors.initials: SW
authors.lastname: Barth
authors.forename: D O
authors.initials: DO
authors.lastname: Stichtenoth
authors.forename: A
authors.initials: A
authors.lastname: Hahn
mesh_terms: D000328:Adult; D000368:Aged; D000975:Antioxidants / Q000008:administration & dosage*; D001120:Arginine / Q000031:analogs & derivatives* / Q000097:blood; D002318:Cardiovascular Diseases / Q000097:blood* / Q000209:etiology / Q000517:prevention & control*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D014803:Vitamin B Complex / Q000008:administration & dosage*
chemical_list: D000975:Antioxidants; D008055:Lipids; D014803:Vitamin B Complex; C018524:N,N-dimethylarginine; D001120:Arginine