Broccoli Extract Sulforaphane Benefits the Heart
A compound commonly associated with broccoli, cauliflower, and other related vegetables may protect the arteries against damage that leads to heart disease, according to a study just released by researchers from Imperial College London. The compound, sulforaphane, appears to boost the activity of a natural protein that protects the arteries against inflammation.
Sulforaphane is a potent antioxidant that has been widely studied and promoted for its anti-cancer properties and for its ability to lower cholesterol. The richest natural source of sulforaphane is broccoli sprouts, although broccoli also provides excellent amounts. Other cruciferous vegetables, including cabbage, brussel sprouts, kale, bok choy, arugula, and collards, also contain sulforaphane.
In the British study, the scientists noted a critical protein known as Nrf2, which helps protect the integrity of blood vessel walls, is lacking in an active form in the branches and bends of arteries, areas that are highly susceptible to damage. The investigators postulated that the lack of active Nrf2 could be the reason why such arteries are susceptible to inflammation and disease. Their study showed that the broccoli extract sulforaphane reduced inflammation at the high-risk locations by activating Nrf2.
To arrive at this conclusion, the investigators used mice engineered to lack Nrf2 and compared their arteries with those of normal mice. They noted that the presence of Nrf2 in straight sections of arteries prevented inflammation of the lining cells, which is an early indication of atherosclerosis and a major risk factor for cardiovascular disease.
When the scientists examined the lining cells of areas susceptible to disease, they found that Nrf2 was bound to a protein that rendered it inactive, which made it unable to protect the artery walls from inflammation and damage. Exposure to sulforaphane reactivated Nrf2 in the susceptible areas, restoring the lining cells’ ability to avoid inflammation.
Previous studies have shown that people and animals that consume a diet high in cruciferous vegetables such as broccoli have a lower incidence of certain cancers, including lung, breast, colon, ovarian, and bladder cancer. The current study showed that sulforaphane may protect against development of atherosclerosis, but it is not known whether eating broccoli and other cruciferous vegetables will provide the same protection as the compound alone. The authors noted that this question will be the focus of future research, as well as discovering whether sulforaphane can reduce progression of disease in affected arteries.
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