Acute methionine loading does not alter arterial stiffness in humans

Area of Science:

• Cardiovascular Medicine
• Nutritional Science
• Physiology

Background:

• Hyperhomocysteinemia is a known cardiovascular disease risk factor.
• Acute elevation of plasma homocysteine impairs endothelial function.
• Vitamin C pretreatment can mitigate these negative effects.

Purpose of the Study:

• To investigate the impact of methionine loading on arterial stiffness.
• To assess the effect of concomitant vitamin C administration with methionine on arterial stiffness.
• To utilize pulse wave analysis for noninvasive assessment of arterial stiffness.

Main Methods:

• Eight healthy males participated in a double-blind, randomized, placebo-controlled study.
• Subjects received oral methionine, methionine plus vitamin C, or placebo.
• Hemodynamic parameters, arterial stiffness, and plasma homocysteine were measured.

Main Results:

• Methionine loading increased plasma homocysteine but did not significantly alter arterial stiffness.
• Combined methionine and vitamin C increased homocysteine similarly but significantly reduced augmentation index.
• Vitamin C's effect on reducing arterial stiffness was observed even with methionine loading.

Conclusions:

• Acute hyperhomocysteinemia alone does not significantly affect arterial stiffness.
• Vitamin C effectively reduces arterial stiffness, independent of methionine loading.
• No significant interaction was found between oral methionine and vitamin C regarding arterial stiffness reduction.