Scorpion Venom Reduces Heart Bypass Failure

People with severe cardiovascular disease usually need a coronary artery bypass grafting, and researchers from the University of Leeds found that a compound from the venom of the Central American bark scorpion – Centruroides margaritatus, could help reduce the number of heart bypass failures.

The study found that margatoxin in at least 100 times more powerful that any other known compound and it can prevent neointimal hyperplasia (the blood vessel's response to injury, which triggers the growth of new cells and causes chronic obstruction of the interior of the vessel).

During a bypass procedure, the injury response starts as the vein adapts to the different circulatory pressures, and the new environment.

The problem is that by growing on the inside of the vein, the new cells restrict blood flow, causing the failure of the bypass.

The margatoxin inhibits a certain potassium ion channel, which is a pore in the cell membrane that reacts to electrical signals and enhances the delivery of the calcium ion.

Professor Beech from the University‘s Faculty of Biological Sciences, lead author of the study said that “we knew from experimental research in immunology that the ion channel Kv1.3 is involved in activating immune system responses and that it’s linked with chronic inflammation problems in the immune system, such as those you see with multiple sclerosis.

“Since our own studies had identified Kv1.3’s presence in injured blood vessels, which are also often complicated by chronic inflammation, we wanted to see if the same immune system blockers would inhibit neointimal hyperplasia.”

Margatoxin surprised the researchers by its extreme ability of suppressing the injury mechanism response.

They had a few good blockers of this ion channel on their list, some developed from plants and this one, coming from scorpion venom, “but margatoxin was the most potent of all these compounds by a significant margin,” said the professor.

Still he adds that it would probably not be a good idea to swallow, inhale or inject this drug, so instead, it might be used as a spray-on treatment to the vein itself, after it’s been removed, waiting to be grafted onto the heart.

This study, published online in Cardiovascular Research, was funded by the British Heart Foundation, the Wellcome Trust and the Medical Research Council.