| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Original Research Communication |
1 From the Department of Surgical Sciences, Section of Forensic Medicine, University of Uppsala, Sweden.
Background: Epidemiologic studies have shown an inverse correlation between acute coronary events and high intake of dietary vitamin E. Recent clinical studies, however, failed to show any beneficial effects of 
-tocopherol on cardiovascular events. Absence of tocopherols other than -tocopherol in the clinical studies may account for the conflicting results.
Objective: This study compared the effect of a mixed tocopherol preparation rich in 
-tocopherol with that of -tocopherol on platelet aggregation in humans and addressed the potential mechanisms of the effect.
Design: Forty-six subjects were randomly divided into 3 groups: -tocopherol, mixed tocopherols, and control. ADP and phorbol 12-myristate 13-acetate–induced platelet aggregation, nitric oxide (NO) release, activation of endothelial constitutive nitric-oxide synthase (ecNOS; EC 1.14.13.39) and of protein kinase C (PKC), and ecNOS, superoxide dismutase (SOD; EC 1.15.1.1), and PKC protein content in platelets were measured before and after 8 wk of administration of tocopherols.
Results: ADP-induced platelet aggregation decreased significantly in the mixed tocopherol group but not in the -tocopherol and control groups. NO release, ecNOS activation, and SOD protein content in platelets increased in the tocopherol-treated groups. PKC activation in platelets was markedly decreased in the tocopherol-treated groups. Mixed tocopherols were more potent than -tocopherol alone in modulating NO release and ecNOS activation but not SOD protein content or PKC activation.
Conclusions: Mixed tocopherols were more potent in preventing platelet aggregation than was -tocopherol alone. Effects of mixed tocopherols were associated with increased NO release, ecNOS activation, and SOD protein content in platelets, which may contribute to the effect on platelet aggregation.
Key Words: Platelets • platelet aggregation • tocopherols • mixed tocopherols • -tocopherol • nitric oxide • endothelial constitutive nitric-oxide synthase • superoxide dismutase • protein kinase C
Related articles in AJCN:
-Tocopherol, the new vitamin E?
This article has been cited by other articles:
|
|
 |
|
  J. Ju, X. Hao, M.-J. Lee, J. D. Lambert, G. Lu, H. Xiao, H. L. Newmark, and C. S. Yang A {gamma}-Tocopherol-Rich Mixture of Tocopherols Inhibits Colon Inflammation and Carcinogenesis in Azoxymethane and Dextran Sulfate Sodium-Treated Mice Cancer Prevention Research, February 1, 2009; 2(2): 143 - 152. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Ravaglia, P. Forti, A. Lucicesare, N. Pisacane, E. Rietti, F. Mangialasche, R. Cecchetti, C. Patterson, and P. Mecocci Plasma tocopherols and risk of cognitive impairment in an elderly Italian cohort Am. J. Clinical Nutrition, May 1, 2008; 87(5): 1306 - 1313. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. H.Y. Wu, N. C. Ward, A. P. Indrawan, C.-A. Almeida, J. M. Hodgson, J. M. Proudfoot, I. B. Puddey, and K. D. Croft Effects of {alpha}-Tocopherol and Mixed Tocopherol Supplementation on Markers of Oxidative Stress and Inflammation in Type 2 Diabetes Clin. Chem., March 1, 2007; 53(3): 511 - 519. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. H. Kang, N. Cook, J. Manson, J. E. Buring, and F. Grodstein A Randomized Trial of Vitamin E Supplementation and Cognitive Function in Women Arch Intern Med, December 11, 2006; 166(22): 2462 - 2468. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. W Clarke, N. C Ward, J. H. Wu, J. M Hodgson, I. B Puddey, and K. D Croft Supplementation with mixed tocopherols increases serum and blood cell {gamma}-tocopherol but does not alter biomarkers of platelet activation in subjects with type 2 diabetes Am. J. Clinical Nutrition, January 1, 2006; 83(1): 95 - 102. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Boullata Natural Health Product Interactions with Medication Nutr Clin Pract, February 1, 2005; 20(1): 33 - 51. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. S. Perona, J. Martinez-Gonzalez, J. M. Sanchez-Dominguez, L. Badimon, and V. Ruiz-Gutierrez The Unsaponifiable Fraction of Virgin Olive Oil in Chylomicrons from Men Improves the Balance between Vasoprotective and Prothrombotic Factors Released by Endothelial Cells J. Nutr., December 1, 2004; 134(12): 3284 - 3289. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. E. Tornwall, J. Virtamo, P. A. Korhonen, M. J. Virtanen, D. Albanes, and J. K. Huttunen Postintervention Effect of Alpha Tocopherol and Beta Carotene on Different Strokes: A 6-Year Follow-Up of the Alpha Tocopherol, Beta Carotene Cancer Prevention Study Stroke, August 1, 2004; 35(8): 1908 - 1913. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. T. Vatassery, Adityanjee, H. T. Quach, W. E. Smith, M. A. Kuskowski, and D. Melnyk Alpha and Gamma Tocopherols in Cerebrospinal Fluid and Serum from Older, Male, Human Subjects J. Am. Coll. Nutr., June 1, 2004; 23(3): 233 - 238. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Devaraj and M. G Traber {gamma}-Tocopherol, the new vitamin E? Am. J. Clinical Nutrition, March 1, 2003; 77(3): 530 - 531. [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
