J. Thambyrajah, J. Townend
Jun 1, 2000
Citations
2
Influential Citations
170
Citations
Quality indicators
Journal
European heart journal
Abstract
Homocysteine, a sulphur-containing amino acid, is an intermediate formed during the catabolism of the essential dietary amino acid methionine. Approximately 80% of plasma homocysteine is protein bound. Only a small amount exists as free reduced homocysteine, as the majority of the unbound portion is oxidized to form diamers (homocystine) or combined with cysteine to form mixed disulphides. The ‘homocysteine theory’ of atherosclerosis arose from the observation that diseases such as homozygous homocystinuria, which are characterized by severe hyperhomocysteinaemia (>0·1 mmol . l ), are associated with premature vascular disease. Mildly elevated levels (0·015– 0·03 mmol . l ) have been found in up to 7% of the population. Epidemiological evidence suggests that even such slight elevation of plasma homocysteine is a risk factor and possibly a causative agent for atherosclerotic disease. Evidence for this includes: