title: No effect of an L-arginine-enriched medical food (HeartBars) on endothelial function and platelet aggregation in subjects with hypercholesterolemia.
abstract: BACKGROUND
  Providing L-arginine as a precursor for nitric oxide has been proposed to improve endothelial function in populations at high risk for cardiovascular events. We studied the effects of dietary L-arginine supplementation with HeartBars (a medical food rich in L-arginine, Cooke Pharma, Belmont, Calif) on flow-mediated dilation and markers of endothelial function in subjects with hypercholesterolemia.
  
  
  METHODS
  We randomly assigned 47 subjects with hypercholesterolemia to receive one HeartBar containing 3.3 g L-arginine each, or a placebo bar, consumed twice daily for 2 weeks. Flow-mediated dilation, platelet aggregation studies, and soluble levels of endothelial and platelet adhesion molecules were obtained before and after the 2-week treatment period.
  
  
  RESULTS
  Baseline and follow-up levels of L-arginine were 78.5 +/- 28.2 micromol/L and 80.7 +/- 26.7 micromol/L, respectively (P =.54). The HeartBar group had no improvement in flow-mediated dilation; changes in brachial artery diameter at baseline and follow-up were 5.52% +/- 3.32% and 4.96% +/- 2.39%, respectively. There were also no changes in the soluble levels of E-selectin and P-selectin by treatment group.
  
  
  CONCLUSIONS
  In our study, 2 weeks of HeartBar supplementation in subjects with hypercholesterolemia showed no favorable effects on endothelial or platelet function.
authors.affiliation: Hypertension and Vascular Disease Center, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
authors.forename: Abdelhamed I
authors.initials: AI
authors.lastname: Abdelhamed
authors.forename: Steven E
authors.initials: SE
authors.lastname: Reis
authors.forename: David C
authors.initials: DC
authors.lastname: Sane
authors.forename: K Bridget
authors.initials: KB
authors.lastname: Brosnihan
authors.forename: Robert B
authors.initials: RB
authors.lastname: Preli
authors.forename: David M
authors.initials: DM
authors.lastname: Herrington
mesh_terms: D000553:Ambulatory Care; D001120:Arginine / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use*; D001916:Brachial Artery / Q000187:drug effects / Q000502:physiology; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology; D005260:Female; D005527:Food, Fortified; D006801:Humans; D006937:Hypercholesterolemia / Q000178:diet therapy*; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000096:biosynthesis / Q000627:therapeutic use; D010974:Platelet Aggregation / Q000187:drug effects* / Q000502:physiology; D011355:Prodrugs / Q000378:metabolism / Q000494:pharmacology / Q000627:therapeutic use; D012039:Regional Blood Flow / Q000187:drug effects / Q000502:physiology; D016896:Treatment Outcome; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology
chemical_list: D011355:Prodrugs; D009569:Nitric Oxide; D001120:Arginine