homocysteine

British  

/ ˌhəʊməʊˈsɪstiːn /

noun

1. an amino acid occurring as an intermediate in the metabolism of methionine. Elevated levels in the blood may indicate increased risk of cardiovascular disease

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homocysteine Scientific  

/ hō′mə-sĭs′tə-ēn′,-ĭn,-tē- /

1. An amino acid used normally by the body in cellular metabolism and the manufacture of proteins. Elevated concentrations in the blood are thought to increase the risk for heart disease by damaging the lining of blood vessels and increasing the risk of blood clot formation. High homocysteine levels are associated with certain vitamin deficiencies and metabolic disorders. Chemical formula: C ₄ H ₉ NO ₂ S.

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Example Sentences

The team found that participants with higher homocysteine levels generally had lower levels of folate and vitamin B12, regardless of sex.

From Science Daily • May 29, 2026

“All three of these B vitamins are needed to remove the amino acid homocysteine from your blood,” says Barnard.

From Time • Aug. 1, 2014

Dr. Smith has also found that the astronauts who experienced a shift in vision also had increased levels of the amino acid homocysteine, often a marker for cardiovascular disease.

From New York Times • Jan. 27, 2014

Another potential marker — the level of homocysteine in plasma — could help distinguish between MCI and healthy controls, but not between MCI and Alzheimer's disease.

From Nature • Jul. 13, 2011

For example, a 1991 study that was cited 1,436 times found that patients with a high level of a compound called homocysteine in their blood had a 27.7-fold elevated risk for vascular disease.

From Scientific American • Jun. 1, 2011