This new drug could keep hearts lacking oxygen

A new therapeutic oxygen release therapy restored the function of oxygen – depleted cardiac tissue in an animal model of global hypoxia in new studies conducted at the University of San Francisco . The study was published in the Journal of PLOS Biology. Body tissue that lacks oxygen is a major hazard, especially for the heart. Such hypoxic conditions can lead to long-term tissue damage or even heart attacks.

The new drug, called OMX-CV, does not appear to cause systemic side effects or to be over-corrected for excessive blood oxygenation, unlike its experimental predecessors. to be toxic. The new drug only distributed its precious cargo of oxygen to the tissues that needed it the most.

Dr. Emin Maltepe, co-author of the paper, was quoted as saying that any tissue with compromised blood flow, whether due to trauma, stroke or heart disease, could potentially be targeted by a patient. treatment like this.

Cardiovascular diseases such as coronary heart disease can starve the heart of oxygen, causing heart dysfunction or heart attack in adults, but heart hypoxia is also a problem in children. . According to the Centers for Disease Control and Prevention (CDC), approximately 10,000 children are born each year with a serious conbad heart defect. During their first year of life, many of these infants must undergo heart surgery, during which time blood can be temporarily removed from the heart, thus leaving the organ devoid of oxygen.

Under normal conditions, the heart consumes more oxygen by weight than any other. organ, and when oxygen levels are low; his demand goes up even higher. The hypoxic heart pumps harder to deliver oxygen to the rest of the body and, paradoxically, needs more and more oxygen itself to maintain its function. A drug that releases oxygen, such as OMX-CV, could alleviate the physical stress badociated with hypoxia and improve recovery after a heart attack or open-heart operation in adults and children.

Hemoglobin-based drugs have also proven to be too effective: they tend to flood the blood with excess oxygen that can itself cause severe tissue damage. In addition, when it is outside of red blood cells, hemoglobin can attach to nitric oxide, a natural muscle relaxant found in blood vessels. Nitric oxide-depleted vessels contract, causing a rise in blood pressure, increasing the risk of heart attack and reducing blood flow to organs as important as the kidneys.

OMX-CV eliminates these problems by using a bacterial protein known as H-NOX. as a base, rather than hemoglobin. The H-NOX proteins contain a "co-factor" called hemic group – the same co-factor that gives its name to hemoglobin – which allows the protein to bind not only to oxygen but also to nitric oxide. By altering the chemical structure of H-NOX proteins, Omniox scientists have reorganized them to make them more resistant to oxygen, while leaving nitric oxide alone. Researchers have also shown that modified proteins bind oxygen so tightly that they only let go when they encounter severely hypoxic tissue.

Published: October 20, 2018 20h05