Premium
Acute and chronic effects of vitamin C on endothelial fibrinolytic function in overweight and obese adult humans
Author(s) -
Van Guilder Gary P.,
Hoetzer Greta L.,
Greiner Jared J.,
Stauffer Brian L.,
DeSouza Christopher A.
Publication year - 2008
Publication title -
the journal of physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.802
H-Index - 240
eISSN - 1469-7793
pISSN - 0022-3751
DOI - 10.1113/jphysiol.2008.151555
Subject(s) - overweight , medicine , sodium nitroprusside , endocrinology , bradykinin , obesity , placebo , vitamin , nitric oxide , receptor , alternative medicine , pathology
We determined the effects of acute intra‐arterial vitamin C administration and chronic oral vitamin C supplementation on the capacity of the endothelium to release t‐PA in overweight and obese adults. Net endothelial t‐PA release was determined in vivo in response to intrabrachial infusions of bradykinin and sodium nitroprusside in 33 sedentary adults: 10 normal‐weight (BMI: 23.4 ± 0.5 kg m −2 ; 7M/3F); and 23 overweight/obese (BMI: 31.2 ± 0.8 kg m −2 ; 15M/8F). In 10 normal weight and eight overweight/obese adults the dose–response curves to bradykinin and sodium nitroprusside were repeated with a coinfusion of the antioxidant vitamin C (24 mg min −1 ). Seventeen of the 23 overweight/obese adults completed a 3 month chronic oral vitamin C (500 mg day −1 ) supplementation intervention. Intra‐arterial administration of vitamin C significantly potentiated t‐PA release in overweight/obese adults. Net release of t‐PA was ∼95% higher ( P < 0.01) after (from −0.9 ± 1.1 to 94.6 ± 16.2 ng (100 ml tissue) −1 min −1 ) compared with before (from −0.8 ± 0.8 to 49.9 ± 7.7 ng (100 ml tissue) −1 min −1 ) vitamin C administration. Daily vitamin C supplementation significantly increased t‐PA release in overweight/obese adults (from 0.2 ± 0.9 to 48.2 ± 6.5 ng (100 ml tissue) −1 min −1 ) before supplementation versus (0.3 ± 0.5 to 66.3 ± 8.7 ng (100 ml tissue) −1 min −1 ) after supplementation. These results indicate that the antioxidant vitamin C favourably affects the capacity of the endothelium to release t‐PA in overweight/obese adults. Daily vitamin C supplementation represents an effective lifestyle intervention strategy for improving endothelial fibrinolytic regulation in this at‐risk population.