title: Low body mass index is a risk factor for impaired endothelium-dependent vasodilation in humans: role of nitric oxide and oxidative stress.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the relationship between body mass index (BMI), including low BMIs, and endothelial function.
  
  
  BACKGROUND
  Epidemiologic study has demonstrated that not only obesity but also a low BMI may be a risk factor for cardiovascular disease.
  
  
  METHODS
  The forearm blood flow (FBF) response to acetylcholine (ACh) and isosorbide dinitrate (ISDN) was measured in 87 healthy young men (15 low BMI, 51 normal, 14 obese, and 7 extremely obese).
  
  
  RESULTS
  Plasma concentrations of 8-hydroxy-2'-deoxyguanosine and serum concentrations of malondialdehyde-modified low-density lipoprotein were higher in low BMI, obese, and extremely obese subjects than in normal subjects and were similar among the low BMI, obese, and extremely obese groups. The FBF response to ACh was greater in the normal group than in the other groups (p < 0.001), and was lower in the extremely obese group as compared with the other groups (p < 0.001). The ACh-stimulated vasodilation was similar between the low BMI group and the obese group. The ISDN-stimulated vasodilation was similar in all four groups. There were no significant differences in ACh-stimulated vasodilation between the four groups after the nitric oxide (NO) synthase inhibitor NG-monomethyl-L-arginine infusion. Co-infusion of vitamin C augmented the FBF response to ACh in low BMI, obese, and extremely obese groups--but not in normal BMI group.
  
  
  CONCLUSIONS
  These findings suggest that not only obesity but also a low BMI may be a risk factor for impaired endothelium-dependent vasodilation through the increased oxidative stress, leading to the reduced bioavailability of NO.
authors.affiliation: Department of Cardiovascular Physiology and Medicine, Hiroshima University Graduate School of Biomedical Sciences, Hiroshima, Japan. yhigashi@hiroshima-u.ac.jp
authors.forename: Yukihito
authors.initials: Y
authors.lastname: Higashi
authors.forename: Shota
authors.initials: S
authors.lastname: Sasaki
authors.forename: Keigo
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Masashi
authors.initials: M
authors.lastname: Kimura
authors.forename: Kensuke
authors.initials: K
authors.lastname: Noma
authors.forename: Satoshi
authors.initials: S
authors.lastname: Sasaki
authors.forename: Keiko
authors.initials: K
authors.lastname: Hara
authors.forename: Hideo
authors.initials: H
authors.lastname: Matsuura
authors.forename: Chikara
authors.initials: C
authors.lastname: Goto
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Oshima
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Chayama
authors.forename: Masao
authors.initials: M
authors.lastname: Yoshizumi
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000328:Adult; D000704:Analysis of Variance; D000975:Antioxidants / Q000494:pharmacology; D001205:Ascorbic Acid / Q000494:pharmacology; D001783:Blood Flow Velocity / Q000187:drug effects; D015992:Body Mass Index; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000209:etiology*; D016022:Case-Control Studies; D004730:Endothelium, Vascular / Q000187:drug effects / Q000503:physiopathology*; D005542:Forearm / Q000098:blood supply; D006801:Humans; D007548:Isosorbide Dinitrate / Q000494:pharmacology; D008297:Male; D009569:Nitric Oxide / Q000502:physiology*; D009765:Obesity / Q000150:complications* / Q000503:physiopathology; D018384:Oxidative Stress / Q000187:drug effects; D010991:Plethysmography; D012307:Risk Factors; D013851:Thinness / Q000150:complications* / Q000503:physiopathology; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D014665:Vasodilator Agents; D009569:Nitric Oxide; D007548:Isosorbide Dinitrate; D000109:Acetylcholine; D001205:Ascorbic Acid