Researchers have identified1 a small molecule that inhibits the synthesis of nitric oxide, which leads to the formation of plaques inside the arteries and increases the risk of ischemic stroke. The molecule, known as asymmetric dimethylarginine (ADMA), could be used to indicate the onset of ischemic stroke at an early age.

ADMA's role in assessing the risk of ischemic stroke in young adults was not well understood. The researchers compared blood ADMA levels of 201 ischemic stroke patients aged between 15 and 50 with 217 age- and gender-matched healthy persons. The blood ADMA levels of stroke patients were found to be significantly higher than those of healthy persons.

In stroke patients, higher levels of ADMA impair the synthesis of nitric oxide. A reduction in nitric oxide bioavailability could therefore enhance atherosclerosis of blood vessel walls. This raises the possibility that increased concentrations of ADMA in the blood could be partly responsible for increased risk of ischemic stroke. Small molecules such as ADMA may alter the basic biochemical processes of vascular endothelial cells.

This is the first study of ADMA's role in premature ischemic stroke, suggesting that ADMA may prove a novel biomarker for indicating the onset of stroke in the young, the researchers say.