Homocysteine Explained

homocysteine and heart healthHeart health is a hot topic – this February and always—in Western medical culture.

There’s a certain four-syllabled amino acid that greatly impacts those conversations, but it’s likely many of them never even include the word. That word is: Homocysteine.

What is Homocysteine?

Homocysteine is a non-protein amino acid. Our bodies can recycle homocysteine into methionine or convert it to cysteine when aided by specified B vitamins.

Homocysteine is biosynthesized from methionine, not taken into the body via nutrients in the diet. In the biosynthesis process, things get a bit complicated…

…beginning with methionine. First, it must receive an adenosine group from ATP (otherwise known as the energy molecule).

That reaction is catalyzed by S-adenosyl-methionine synthetase, a protein enzyme. SAM, or S-adenosyl-methionine, is the product of that reaction. SAM transfers a methyl group to another molecule called an “acceptor”.

At that point, hydrolysis occurs, yielding L-homocysteine, which can be then converted back into l-methionine or into l-cysteine.

That’s a lot to take in, but the recycling process is a very important action in our bodies, and it’s important to understand it if we are to understand homocysteine’s impact on health.

How is it related to heart health?

That recycling is important. A high blood level of homocysteine, known as hyperhomocysteinemia, makes us more vulnerable to injury of the endothelial cells, which can lead to vessel inflammation and, eventually, death of important tissues. That makes the condition a possible risk factor for coronary artery disease.

artherosclerosis disease

Plaque blocking coronary arteries and blood flow

The coronary arteries supply the heart with necessary oxygenated blood. When that blood flow is blocked by plaque, the disease occurs.

We aren’t sure, still, if high levels of homocysteine are independent risk factors for blood clots, strokes and heart attacks. But we are sure that high levels of homocysteine and cardiovascular disease are linked.

That’s just one reason – of many – it’s important to talk to your practitioner about ways to support your hearth health as you age. Find out what supplements you might want to add to your regimen here.