Effect of chronic oral supplementation with vitamins on the endothelial function in chronic smokers.
Cigarette smoking has been associated with endothelial dysfunction including impaired endothelium-dependent flow-mediated dilation (FMD). In cigarette smokers, increased oxygen-derived free radicals have been suspected of being one of the major causes of endothelial dysfunction, owing possibly to the inactivation of nitric oxide by free radicals. Vitamins C and E are widely used antioxidant vitamins, which have also been reported to effectively improve the endothelial function in several conditions. To test the effect of moderate-term oral antioxidant vitamin supplementation on the endothelial function in smokers, the authors evaluated the combined effect of vitamins C and E, administered in normal dosages, on FMD in young male smokers. A prospective interventional study was performed. In 15 healthy male subjects (mean age, 24.4 +/-2.5 years old). They studied FMD in the brachial artery by using high-resolution ultrasound. The vascular effects of moderate-term oral supplementation with vitamin C (1.0 g/day) and vitamin E (500 mg/day) were determined during reactive hyperemia, which causes endothelium-dependent FMD. They performed a vascular function study 3 times including before vitamin supplement, after 25 days of vitamin supplement, and 4 weeks after the cessation of the vitamin supplement. The flow-mediated dilator response measurements were repeated twice a day before vitamin supplements, and the repeatability obtained from these measurements was found acceptable (variability of FMD <2%). The oral antioxidant vitamin supplement significantly restored FMD (3.8 +/-2.2% vs 5.9 +/-2.5%; p<0.05), however, this effect disappeared 4 weeks after the vitamin supplementations ended. The combined usual dosage of vitamins C and E supplements was found to improve the endothelial function in chronic smokers.
Takase
Bonpei
B
National Defense Medical College, Saitama, Japan. dui1577@db3.so-net.ne.jp
Etsuda
Hirokuni
H
Matsushima
Yoshihiro
Y
Ayaori
Makoto
M
Kusano
Hiroyuki
H
Hamabe
Akira
A
Uehata
Akimi
A
Ohsuzu
Fumitaka
F
Ishihara
Masayuki
M
Kurita
Akira
A
D000284:Administration, Oral; D000328:Adult; D000975:Antioxidants / Q000008:administration & dosage* / Q000494:pharmacology; D001205:Ascorbic Acid / Q000008:administration & dosage* / Q000494:pharmacology; D001916:Brachial Artery / Q000187:drug effects / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000187:drug effects*; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012907:Smoking / Q000188:drug therapy*; D013997:Time Factors; D014810:Vitamin E / Q000008:administration & dosage* / Q000494:pharmacology
D000975:Antioxidants; D014810:Vitamin E; D001205:Ascorbic Acid