A stroke in the body happens when a clot keeps blood from reaching cells in the brain. This causes the brain cells to switch to other metabolic pathways that don't necessarily rely on oxygen. However, these other metabolic pathways create an acidic environment within the brain, which causes the pH to drop drastically - a condition deemed acidosis. The brain cells - in an acidic environment and with no oxygen available - then begin to die off and cause irreparable damage to the brain.
Research in the past has linked a specific ion channel, called acid-sensitive ion channels (ASICs), that activate when the cell looses its connection to oxygen. These ion channels pump out calcium ions which have a toxic effect in the brain when they reach abnormally high levels. Previously, scientists had identified a specific peptide (psalmotoxin 1) in Tarantula venom that specifically blocked ASICs. In the study conducted with the Tarantula venom, the rats that had strokes were much more protected from acidosis in the brain when administered psalmotoxin 1 for treatment.
In this current study, researchers focused on the venom of the Australian Funnel Web Spider (Hadronyche infensa) and a disulfide-rich peptide within the venom called Hi1a. For reference, the Australian Funnel Web Spider Hadronyche infensa is an incredibly venomous spider. Their presynaptic neurotoxins target sodium and ion channels within the body and induce spontaneous, repetitive firing of action potentials in autonomic and motor neurons, thus causing an increase in adrenaline, acetylcholine, and noreprinephrine. The researchers discovered that Hi1a specifically targets ASICs, and does an incredibly fantastic job at doing so. Even so, Hi1a has a faster time getting to the ASICs and inducing an effect on the channels than the peptide found in Tarantula venom. So the researchers in this study induced rats to have strokes and gave them Hi1a to observe the effects. In the rats tested, the Hi1a peptide protected up to 77 percent of the brain cells that were affected. Specifically, it saved brain tissue that was hit the hardest from the lack of oxygen and severely limited peripheral damage to other parts of the brain.
The potential of this discovery is very high, for this peptide gives doctors and medical professionals a greater window to treat and prevent damage from a stroke. As of now, the use of tissue plasminogen activator (tPA) to restore blood flow is the only FDA approved treatment option for strokes. This alternative could now help more patients that suffer strokes and prevent long-term damage. However, the medical world is still a long ways away from venom-based treatment. It will take a lot more research and time to develop a capable drug or treatment that is based on the peptides found in venom. More specifically, more research needs to be done to determine potential problems that may arise using this method of treatment; lethal doses, effective doses, and risk assessments all need to be completed as well as trials for clinical use. But the study does prove that spider venom, although toxic, does contain chemicals that may benefit our lives and our health.
If you want to read more, the story written on this study can be found here:
The published research paper within the PNAS Journal can be found here:
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