Imperial College London
Alternate

ProfessorJohnChambers

Faculty of Medicine, School of Public Health

Professor of Cardiovascular Medicine & Epidemiology
 
 
 
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Contact

 

+44 (0)7866 365 776john.chambers

 
 
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Location

 

172Medical SchoolSt Mary's Campus

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Summary

 

Publications

Citation

BibTex format

@article{Chambers:1999,
author = {Chambers, J and Obeid, OA and Jean-Marie, J and Kooner, JS},
journal = {Heart},
title = {Increments in plasma homocysteine after dietary animal protein are associated with vascular endothelial dysfunction in human subjects},
volume = {81},
year = {1999}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The vascular effects of physiological, diet-induced increments in plasma homocysteine are not known. We hypothesized that there is a graded, inverse relationship between homocysteine concentration and endothelial function, and that physiological increments in plasma homocysteine following methionine or dietary protein induce vascular endothelial dysfunction. We studied 18 healthy volunteers aged 18-59 years. Brachial artery flow-mediated, and glyceryltrinitrate (GTN) induced, dilatation were measured after; i. oral L-methionine (10, 25, 100 mg/kg); ii. dietary animal protein (lean chicken 551±30g, comprising 3.2±0.2g methionine); and iii. methionine-free amino acid mix (100 mg/kg). Methionine (10, 25, 100mg/kg) induced a dose-related increase in homocysteine (9.4±1.3 to 12.2±2.1, 17.6±2.6, and 26.1±4.2 μmol/l, respectively p<0.001), and reduction in flow-mediated dilatation (4.1±0.8 to 2.1±0.8, 0.3±0.8, and -0.7±0.8%, respectively p<0.001) at 4 hours. Compared to usual meal, animal protein increased plasma homocysteine (9.6±0.8 to 11.2±0.9 μmol/l, p=0.005) and reduced flow mediated dilatation (4.5±0.7 to 0.9±0.6%, p=0.003). Methionine-free amino acid mix did not induce any changes. GTN induced dilatation was unchanged throughout. Our results provide evidence of an inverse relationship between homocysteine concentration and endothelial function, and show that physiological increments in plasma homocysteine after low-dose methionine and dietary animal protein are associated with vascular endothelial dysfunction. These results imply that diet related changes in homocysteine may have adverse vascular effects in patients with coronary artery disease.
AU  - Chambers,J
AU  - Obeid,OA
AU  - Jean-Marie,J
AU  - Kooner,JS
PY  - 1999///
SN  - 1355-6037
TI  - Increments in plasma homocysteine after dietary animal protein are associated with vascular endothelial dysfunction in human subjects
T2  - Heart
VL  - 81
ER  -
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