One of the World's Deadliest Spider Venoms Could Help Heart Attack Patients

Researchers have reportedly discovered that the venom from one of the world's deadliest spiders may be able to help recovering heart attack patients and extend the lives of procured donor hearts.

According to a study released on Thursday in the peer-reviewed journal Circulation, a group of researchers from the University of Queensland in Australia has found that a molecule in the venom from Australian funnel-web spiders has been linked to improving heart cell viability, and could be used in medical treatments for heart attacks and donation retrieval for transplants.

Professor Glenn King of the University of Queensland and fellow researchers Dr. Nathan Palpant and cardiologist Peter Macdonald explained in their research paper that the venom from the species, also known as the Fraser Island funnel-web spider, contains the protein Hi1a, which reportedly interrupts the message signaling for a cell to die in instances of oxygen deprivation, such as during a heart attack or transplant.

"Ischemia-reperfusion injury [IRI] is one of the major risk factors implicated in morbidity and mortality associated with cardiovascular disease," they write in their report. "During cardiac ischemia, the build-up of acidic metabolites results in decreased intracellular and extracellular pH that can reach as low as 6.0-6.5."

King told Newsweek that he and his team were able to isolate the peptide they isolated from the Australian funnel-web spider, which has "the most complex venom of any terrestrial venomous animal.

"My lab uses venoms as a source of eco-friendly insecticides...and human therapeutics," he said. "We had previously shown that this peptide prevents stroke-induced brain injury. Since stroke is an ischemic event (i.e., it causes loss of oxygen supply to the organ) we wondered whether the peptide might also be beneficial for ischemic injuries of the heart, which along with the brain is the organ most susceptible to ischemic injury."

Palpant also shared with Newsweek that their research into the drug with the venom's molecule "has shown remarkable safety and efficacy.

"Despite decades of research, no drugs have been developed for clinical use that block injury responses of the heart to ischemia, which occurs during heart attacks and heart transplant," he added. "This is a major area of unmet need."

"The problem with the heart is that it has zero capacity to regenerate," King told The Guardian of the project. "People might survive a heart attack but...those muscle cells will never come back, so they've got a very damaged heart. That's why any tissue you can rescue during or after the heart attack is really, really important."

Indeed, according to the University of California, Los Angeles Heart and Vascular Services, cardiac tissue cannot regenerate once damaged. Deterioration of the muscle can thus result in heart failure, which affects 500,000 Americans annually.

"The number one reason why people go to the hospital for cardiovascular complications is related to lack of blood flow to the heart, such as heart attacks," Palpant told Newsweek. "Cardiovascular disease remains the leading cause of death in the world."

The venom of Australian funnel-web spiders also contains delta-hexatoxins, which are the peptides that make the venom dangerous for humans and primates. There have been 13 recorded deaths from funnel-web spiders, though none since anti-venoms became available in the 1980s. It is estimated 30 to 40 people are bitten every year.

When a person is bitten by the spider, the venom blocks nerve impulses to the muscles and causes paralysis of the entire nervous system. This leads to a range of symptoms including muscular twitching, breathing difficulty, fast pulse and increased blood pressure, among others.

"While thousands of molecules are found in the Fraser Island funnel-web venom, only one is known to be capable of killing a human," Palpant emphasized. "The remaining molecules are of particular interest as potential new drugs. Indeed, venom-derived drugs have been successfully developed for clinical use."

The Hi1a molecule's potential has left Macdonald particularly hopeful about the future of cardiac medicine, especially in relation to heart transplants.

"Usually, if the donor heart has stopped beating for more than 30 minutes before retrieval, the heart can't be used," he said in a statement to the Australian Broadcasting Corporation (ABC). "Even if we can buy an extra 10 minutes, that could make the difference between someone having a heart and someone missing out.

"For people who are literally on death's door, this could be life-changing," he added.

"It's always a race for the surgeon to try and keep that heart alive before they get it into the recipient. We think the drug [candidate] will be able to be used to increase the number of donor hearts that are going to be available for transplant," King also shared with The Guardian.

King told the University of Queensland News that he hopes Hi1a could one day be administered by emergency services responding to the scene.

"This is particularly important in rural and remote parts of Australia where patients and treating hospitals can be long distances apart—and when every second counts," he told the outlet. "Also, this could help for the transfer of donor hearts for cardiac transplantation—allowing these donor hearts to be transported over longer distances and therefore increasing the network of available donors and recipients."

Palpant also said that the next step in the research process is to team up with "chemists and clinicians around the world to advance Hi1a into clinical testing hopefully within the next few years."

"So far, we have tested this in rodents and human heart cells derived from stem cells in models of heart attack and heart transplant. Large animal model testing is currently underway."

King confirmed with Newsweek that he, Macdonald and Palpant will also proceed with additional tests in species with myocardial infarction (MI).

"The next steps for us are testing the compound in preclinical pig models of MI and heart transplant, finalizing the safety and toxicity testing, and scaling up the manufacture of the peptide for human clinical trials," he said. "We hope to begin clinical trials for heart transplants in late 2022, MI in 2023, and stroke soon thereafter."

Newsweek reached out to Macdonald for comment but did not hear back in time for publication.

In 2018, Colossus the Australian funnel-web spider made headlines when he was obtained by the Australian Reptile Park in Somersby, New South Wales, and "milked" as part of a project to create additional anti-venom serums and medications.

Updated on 7/19 at 3:15 p.m. to include statements Nathan Palpant made to Newsweek.

Updated on 7/23 at 4:55 p.m. to include statements Glenn King made to Newsweek.