Snake venom has always been thought as dangerous, but scientists have found a protein in venom that could be an important ingredient for making a safer antiplatelet drug. Pretty soon, snake venom could replace aspirin in thinning blood without the side effects.
According to the study by National Taiwan University in Taipei researchers, a drug based on a protein from the venom of the Tropidolaemus wagleri species, called trowaglerix, effectively prevented the formation of blood clot in mice without excessive bleeding.
Antiplatelet drugs, or medications prescribed to prevent platelets from clumping together, are usually given to patients with heart problems. This would reduce their risk of heart attack or stroke. The drugs act by thinning the blood to let it flow more freely to the brain. Bleeding is the most common side effect of antiplatelet drugs, a class that includes aspirin.
For the drug research, scientists studied the venom from Wagler's pit viper, a species that thrive in the Southeast Asian rainforest. They are usually medium-sized and can grow up to four feet in length. While all pit vipers are venomous, the Wagler's pit viper is not usually aggressive. But once they strike, they can do it in succession rather than a quick motion. Still, their strike is not as rapid as the strike from other viper species.
The snake's venom is potentially deadly -- it's strong, but usually doesn't cause human deaths. Once a person is bitten, he will usually feel a burning sensation, which will progress to swelling then tissue necrosis.
The Wagler's pit vipers mostly live on trees and can be found in southern Thailand, Singapore, peninsular Malaysia, southern Vietnam, and some parts of Indonesia.
With the new findings published Thursday in Arteriosclerosis, Thrombosis and Vascular Biology, the experimental drug based on the snake venom could provide a much safer alternative in the management of blood clots in patients.
Co-lead author of the study, Tur-Fu Huang, explains that there are snake venoms that are neurotoxic, which affects the brain, and those that are hemorrhagic, affecting the coagulation of the platelets. For the new experiment, the researchers used venom that is hemorrhagic, CNN reported.
Huang and the team found that trowaglerix interacted with a protein that is found on the surface of platelets called glycoprotein VI (GPVI) and according to co-lead author Y. Jane Tseng, "Not every snake venom acts in similar mode on platelets."
Previous studies have shown that platelets that are missing the GPVI reduce bleeding and also cannot form blood clots. This led researchers to believe that inhibiting GPVI activity not only prevents the clumping of platelets, but also stop excessive bleeding. Looking at the structure of the new drug, scientists came up with a design that blocks aims at blocking the activity of GPVI.
As researchers tested a new drug for platelets, they found that trowaglerix stopped them from clumping together. They then used mice to test out the drugs and found that mice treated with the drug had a slower formation of blood clots compared to the group that wasn't treated. Also, the treated group did not bleed longer compared to the untreated group.
But even upon learning more about the promising trowaglerix, the team acknowledges the need to do further testing in both animals and humans to ensure its safety and efficacy. The team is now looking for ways to improve the design of the drug.
"In general, this type of molecule design does not last long in the body, so techniques like formulation or delivery system are likely needed to extend the exposure time in the human body," says Dr. Tseng.
"The design must also be optimized to ensure that the molecule only interacts with GPVI and not other proteins which can cause unintended reactions."[Featured Image by reptiles4all/iStock]