How Estrogen Protects Women from Heart Disease

Pre-menopausal women receive heart and blood vessel protection from estrogen

(RxWiki News) Women may be getting an added boost of protection from heart disease. Natural hormones might explain why men have higher rates of heart disease yet post-menopausal women experience a spike in cardiovascular disease.

Estrogen may protect women from cardiovascular disease by keeping the body's immune system in check. The hormone keeps white blood cells from sticking to the interior of blood vessels, which can lead to dangerous plaque blockages.

"Talk to your doctor about natural estrogen supplements."

Dr Suchita Nadkarni, study leader and a physician at the William Harvey Research Institute at the Queen Mary University of London, said that researchers have long known that estrogen protects pre-menopausal women from heart disease, but were not sure why.

He said the study provides insight into how estrogen may protect blood vessels, which could be vital in developing new treatments.

Investigators compared white blood cells from men and pre-menopausal women blood donors. They discovered that cells from pre-menopausal women have considerably higher levels of protein annexin-A1 on the surface of white blood cells, which are key to protecting from infection. They also observed that annexin-A1 and estrogen were strongly linked to a woman's menstrual cycle.

Scientists found that the estrogen can move annexin-A1 from inside the white blood cells, its usual location, to the surface of cells. This helps prevent the cells from sticking to blood vessel walls where it causes vascular damage.

When activated, white blood cells stick to blood vessel walls to aid with infection, but if it happens too often, it can damage blood vessels, leading to heart disease. However, when annexin-A1 remained on the surface of the white blood cells, it prevented the sticking.

Dr Nadkarni said the research showed a clear relationship between estrogen levels and how the white blood cells behaved. He said that suggests the hormone must maintain a delicate balance between fighting infections and protecting arteries from heart disease.

The study is published in American Heart Association journal Arteriosclerosis, Thrombosis and Vascular Biology.

Review Date: 
August 12, 2011