Spider Venom Could Be The Cure For This Rare And Deadly Type Of Epilepsy, According To A New Study
The venom showed success in trials with epileptic mice.
Tarantula venom could be used to cure and even reverse the effects of Dravet syndrome, a severe and frequently deadly form of epilepsy that develops in infancy, according to new Australian research.
Dravet syndrome is a rare form of epilepsy that kills at a rate 30 times higher than other types of childhood-onset epilepsies.
Dravet syndrome affects approximately 1% of people who suffer from epilepsy.
The syndrome is associated with long seizures that can last more than 10 minutes and are often initially triggered by changes in temperature, such as being submerged in a warm bath.
The seizures are also unpredictable and generally resistant to anti-epileptic drugs.
Dravet syndrome can also result in developmental problems such as severe intellectual disability and disability of movement.
So, how could tarantula venom help?
The majority of Dravet syndrome cases are caused by a genetic mutation that leads to a loss of function in a gene known as SCN1A.
The gene is important because it produces a protein that controls the electrical properties of neurons in the brain (epileptic seizures are caused by a disturbance in the electrical activity in the brain).
Children with Dravet syndrome do not produce enough of the protein to control the electrical activity and this results in long, severe seizures.
A team of Australian researchers has published a study this week in the Proceedings of the National Academy of Sciences of the United States of America that found the venom of the West African Tarantula contains peptides that make up the deficit in the protein to control the epileptic seizures.
The researchers from the Florey Institute of Neuroscience and the University of Queensland showed that the tarantula venom could reduce the seizures in mice with Dravet syndrome, as well as prolong their lives.
Professor Steven Petrou, director of the Florey Institute of Neuroscience and lead author of the paper, told BuzzFeed News that this was an example of precision medicine (research that looks at the genetic basis of diseases and then designs cures by fixing those specific problems).
"Most treatments for epilepsy are looking at tens of thousands or hundreds of thousands of drugs, hoping to find one that stops the seizures. We did this in one step, which shows how precision medicine works with fundamental knowledge of the disease," said Petrou.
While this study was only performed in mice, Petrou says that new animal models that look at specific genetic changes like this one show higher rates of success when transferred to human trials compared to traditional animal experiments.
The way that the tarantula venom behaves in the brain is no coincidence. The effect that the venom has on the SCN1A-produced protein (keeping sodium channels open) is the same mechanism that would paralyse the small invertebrates it typically preys on.
"We are exploiting this effect for clinical use," said Petrou.
"We know already that biology has spent millions of years fine-tuning the action of these peptides in order to incapacitate prey and we thought, 'Can we use them in a way that might be medically useful?'"
Professor Mark Cook, director of the Graeme Clark Institute at the University of Melbourne and an epilepsy researcher, told BuzzFeed News that this is "very exciting work, showing how detailed understanding of the neurophysiology behind this terribly disabling epilepsy can be understood and approached with a very sophisticated 'precision medicine' view."
Petrou is optimistic the new treatment will not only stop seizures, but reverse all of the developmental disabilities that are associated with Dravet syndrome, such as intellectual disabilities, movement disability, and personality disorders, if applied early enough.
"We've shown a very important proof of concept that if you alter the function of a protein this way with a drug, you can fix seizure controls, you can fix the neurons, and you can fix all of the other things that go wrong related to that."
Petrou and his team will now work with companies to develop the tarantula venom into a drug that can accurately target the protein in the brain for human trials.