Interrelationship between diabetes and homocysteine metabolism: hormonal regulation of cystathionine beta-synthase.

Plasma homocysteine levels are elevated during diabetes when there is atherosclerosis or insufficient renal function; however, diminished plasma homocysteine concentrations are observed in diabetes without complications. Recent studies have demonstrated that under diabetic conditions, the catabolism of homocysteine was enhanced by transcriptional regulation of hepatic cystathionine beta-synthase and these changes were prevented by treatment with insulin.