An international research conducted by the University of Maastricht (Netherlands), with the participation of the Autonomous University of Madrid (UAM) has discovered why, compared to other body organs, the brain has an extreme sensitivity to oxygen deprivation. The study found that NOX4 enzyme plays a crucial role in cerebral infarcts.  The finding opens new perspectives to prevent brain damage after suffering a heart attack.

The study, published in PNAS, shows that NOX4 increases its expression in various organs when a lack of oxygen occurs. Although this causes few adverse effects on most organs, the increase of this enzyme in the brain is devastating.

“For a long time it was known that oxygen deficiency causes damage to the brain, but it was not clarified why. Knowing the crucial role of the enzyme NOX4 opens the door to new treatment possibilities to protect the body during a heart attack,” says Harald Schmidt, a professor at Maastricht and lead author of the article.

Now, with the support of the European Research Council (ERC), researchers are working on developing drugs that fight the devastating effects caused by NOX4 in the brain.

NOX4 and strokes

A stroke is caused when a blood clot blocks a blood vessel in the brain preventing oxygen from getting to some parts of the organ. To avoid the death of the patient, it is essential break up the clot as soon as possible using anticoagulants or a catheter.

Even though a clot is addressed quickly, people who survive a stroke usually have to face the consequences associated with damage, which can include paralysis, speech problems or memory loss.

The experts describe that NOX4 has a crucial role in specific brain infarcts. First, this enzyme causes the breakdown of cells that form the blood brain barrier which, among other functions, serves as a natural division to protect the brain from the blood and other components outside the brain. Second, NOX4 activates a self-destruct mechanism in neurons.

When the NOX4 gene is removed, or its activity is inhibited by the use of drugs, both the blood brain barrier and neurons remain intact and brain damage is prevented. “If there is no presence of NOX4 enzyme, brain cells and the blood brain barrier remain protected without harmful consequences for the brain,” the researchers detail.

 

Source: SINC