Vitamin E Protects Brain After Stroke

A specific kind of vitamin E called tocotrienol can prevent nerve cells from dying following a stroke—at least in mice. Researchers at Ohio State University found that tocotrienol stops an enzyme in the brain from releasing fatty acids that eventually kill neurons.

Vitamin E occurs naturally in eight different forms. The best-known belongs to a variety called tocopherols. The vitamin E used in this study, tocotrienol or TCT, is not abundant in the American diet but is available as a nutritional supplement. The richest source of tocotrienol is palm oil and is a common component of a typical Southeast Asian diet.

"Our research suggests that the different forms of natural vitamin E have distinct functions," Chandan Sen, professor and vice chair for research in Ohio State's Department of Surgery, said in a statement. "The relatively poorly studied tocotrienol form of natural vitamin E targets specific pathways to protect against neural cell death and rescues the brain after stroke injury."

The study found that an enzyme which is always present in the brain is activated by high levels of glutamate following a stroke. The toxic enzyme, called cPLA2, releases a fatty acid called arachidonic acid into the brain that kills neurons. But when Sen and colleagues introduced the tocotrienol vitamin E to cells that had already been exposed to excess glutamate, the release of fatty acids was reduced by 60 percent when compared to cells exposed to glutamate alone. And cells exposed to TCT were almost four times as likely to survive as those cells which were exposed to glutamate alone.

"We found that it can be put in check by very low levels of tocotrienol," Sen said. "So what we have here is a naturally derived nutrient, rather than a drug, that provides this beneficial impact."

The amount of tocotrienol needed to achieve the protective effects is small—about 10 times lower than the average amount of tocotrienol circulating in the blood of those people who consume the vitamin regularly.

The research appears online and is scheduled for later print publication in the Journal of Neurochemistry.

According to the CDC, about 795,000 people suffer strokes each year in the United States. They are a leading cause of long-term disability. While almost 75 percent of strokes occur in people over the age of 65, they can strike at any age.