A Reddit user claims to have regained feeling in their previously numb foot after receiving a bite from a brown recluse spider.
"I had major foot surgery over 10 years ago and lost feeling in two of my toes," the user said. "That was until a friendly brown recluse bit my foot right where my nerve endings were cut off. I woke up this morning and could immediately feel my toes."
The post was met by some skepticism from other users. Brown recluse spiders aren't native to Oregon, where the poster was based, and most spider species are unlikely to bite a human unprovoked.
"The truth is, lots of skin conditions, infections, and even insect bites are misdiagnosed as spider bites all the time," one user said. However, the question still stands: could a brown recluse spider bite fix damaged nerve endings?
The brown recluse spider is one of the most venomous spiders in North America. They are generally found in the central and southern U.S., and can often find their way into people's houses. While they don't tend to bite unprovoked, it's possible for them to get caught up in bedding or clothing, which they may perceive as a threat.
In many cases, the initial bite is totally painless. Symptoms from the venom may take several hours to develop, and then pain, swelling, nausea and fever can set in. A small white blister usually develops and, in severe cases, tissue death can occur around the bite site.
"Spider venoms are complex cocktails that contain hundreds to thousands of compounds that primarily activate or inhibit the activity of neuronal ion channels," Glenn King, a professor and venom expert at the University of Queensland, Australia, told Newsweek. "It is entirely possible that recluse spider venom contains compounds that reactivate lost nerve function. However, in my humble opinion, it would be unlikely for this to be a long-lasting effect."
Irina Vetter, a professor at the University of Queensland who studies pain and the therapeutic applications of animal venom, explained that, based on the information provided in the Reddit post, the results were unlikely to be caused by a spider bite.
"Since the claim is medically and scientifically unsubstantiated it is a bit hard to comment on exactly what happened, or did not happen," she told Newsweek. "It's implausible but perhaps not impossible.
"What I can say is that venoms are a very rich source of bioactive compounds that can target the sensory system. For example, a substance called "nerve growth factor"–which does what the name implies–was originally discovered in snake venom."
While Irina said that nerve growth factor isn't widely used as a treatment today, it appears to play an important role in wound healing, and researchers are working to develop therapeutic treatments based on this molecule.
"However, there is no evidence that venom from the brown recluse spider contains anything similar [to nerve growth factor] or indeed that similar substances could have been what might have helped this person, or others with similar conditions," Vetter said.
Animal venoms are incredibly complex, and several well-known drugs have been based on the chemicals that they contain. "There are already six drugs derived from animal venoms, including the blockbuster antihypertensive drug captopril and the anti-diabetic drug exenatide," King said. "Captopril is actually derived from the venom of a deadly Brazilian viper, Bothrops jararaca."
King has co-founded a company, called Infensa Bioscience, that is developing a spider-venom-based treatment for strokes and heart attacks.
"These outcomes are possible because venoms are highly complex and, even though some venoms might contain one or two compounds that are dangerous to humans, there might be hundreds more that are benign to humans and some that might even be therapeutically useful," he said.
London's Natural History Museum has estimated that there are over 200,000 venomous animal species known to science, including spiders, snakes, bees and jellyfish. Only a small fraction of these have so far been found to have therapeutic value, although many of them have yet to be studied.
"Nobody should ever intentionally get bitten/stung by any venomous animal in an attempt to improve their health," Vetter said. "I would, however, encourage everyone to support venom research as we may one day develop new medicines from venom, as we have already in the past."
Newsweek contacted the poster for comment.
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