Homocysteine, a toxic waste product that results from the metabolism of another amino acid, is used as a marker for cardiovascular disease risk because of its damaging effects on blood vessels. Homocysteine may contribute to heart disease risk in a number of ways. Some health experts regard your homocysteine levels as an important risk factor for heart disease independent of your cholesterol levels, while others feel that homocysteine's effects mainly occur through its interaction with cholesterol.
Blood Clotting
Reducing elevated homocysteine levels improves blood vessel function and prevents blood clot formation associated with elevated cholesterol, according to researchers at the Center for Molecular and Vascular Biology, Leuven, Belgium. In the laboratory animal study, a genetic therapy to inhibit homocysteine formation improved function of the endothelium -- the inner lining of blood vessels, so that blood clotting was inhibited. The homocysteine-lowering therapy did not decrease arterial plaque formation, in this study, published in the June 2011 issue of the "Journal of Molecular Medicine."
Arteriosclerosis
One theory of arteriosclerosis describes a buildup of homocysteine, which promotes arterial plaque formation and damage to the arteries, as a causative factor, according to Kilmer S. McCully, M.D., author of the book, "The Homocysteine Revolution." Homocysteine accumulates when levels of vitamins B6 and folic acid are inadequate, says McCully. The modern Western diet, high in refined and process foods can cause suboptimal levels of these vitamins, with resultant damaging effects. Homocysteine encourages low density lipoprotein, LDL, the bad form of cholesterol, to clump together, forming homocysteine-cholesterol hybrid molecules which initiate atherosclerosis. The homocysteine hypothesis helps explain some cases of atherosclerosis where cholesterol levels are normal or only slightly elevated.
Artery-Damaging
Cholesterol is protective to arteries and only becomes harmful when acted upon by homocysteine, says Art Dash, M.Sc., M.S., Ph.D., author of the book, "Secrets to Lowering Cholesterol with Nutrition and Natural Supplements, Safely." As Dash explains, homocysteine destroys artery walls and the body reacts by using cholesterol to plaster over the damaged areas. Think of homocysteine as a waste product and do what you can, primarily eating a heart-healthy diet low in processed foods, to keep it from accumulating. Supplementing with vitamin B12, folic acid, vitamin B6 and vitamin B2 can also help ensure adequate amounts of these homocystein-inhibiting nutrients.
Genetic Influences
A genetic component of folic acid metabolism may contribute to homocysteine accumulation and cardiovascular risk factors, say researchers of a study published in the May 2011 issue of the journal "Molecular and Cellular Biochemistry." This would imply that a defect in folic acid metabolism may be at fault in causing high homocysteine levels and resulting atherosclerosis, in some people. For individuals with faulty folate genes, folate supplementation, as opposed to cholesterol-lowering, may the key to lowering cardiovascular disease risk. The study was conducted at the Laboratory of Animal and Human Physiology, Department of Animal Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
References
- "Journal of Molecular Medicine"; Correction of Endothelial Dysfunction After Selective Homocysteine Lowering Gene Therapy Reduces Arterial Thrombogenicity but Has No Effect on Atherogenesis; F. Jacobs, et al.; June 2011
- "The Homocysteine Revolution"; Kilmer S. McCully; 1999
- "Secrets to Lowering Cholesterol with Nutrition and Natural Supplements, Safely"; Art T Dash; 2009
- Molecular and Cellular Biochemistry"; "Tetra Primer Arms-pcr Relates Folate/Homocysteine Pathway Genes and Ace Gene Polymorphism with Coronary Artery Disease; R. Masud, et al.; May 2011
- Women's Heart Foundation: Glossary of Terms
