Medical

Frogs' resistance to their own poison could offer lessons for pain relief

Frogs' resistance to their own...
The sequenced the genes of a variety of frogs, including  the phantasmal poison frog
The sequenced the genes of a variety of frogs, including  the phantasmal poison frog
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Toxins found in some frogs, such as the phantasmal poison frog, could hold important lessons for pain relief in humans
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Toxins found in some frogs, such as the phantasmal poison frog, could hold important lessons for pain relief in humans
The phantasmal poison frog may hold some clues for pain relief in humans
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The phantasmal poison frog may hold some clues for pain relief in humans
The sequenced the genes of a variety of frogs, including  the phantasmal poison frog
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The sequenced the genes of a variety of frogs, including  the phantasmal poison frog

How is it that some frogs are able to flush toxins through their bodies that poison would-be predators without causing any harm to themselves? Scientists have pinpointed the mechanism that enables some types of frog to dodge the danger, identifying a very subtle genetic mutation that could inform the development of new drugs to treat pain and even nicotine addiction.

With opioid addiction already a huge problem, scientists are on the lookout for alternative forms of pain relief, and a lot of that work focuses on the receptors that determine which signals make their way through the body. These receptor proteins live on the outside of cells and decide which molecules are allowed in, and by studying this process researchers have uncovered potential pain relievers in the form of snail venom, green lights and even the power of love.

When it comes to poisonous frogs, medical scientists have long been intrigued by something called epibatidine. This neurotoxin binds to predator's receptors and triggers effects like hypertension, seizures and death, while leaving the frog itself unharmed. Hundreds of experimental compounds have been developed from epibatidine, but have ultimately failed to deliver due to adverse side effects.

A research team led by scientists at the University of Texas gathered tissue samples from 28 species of frog, made up of some that use epibatidine such as the phantasmal poison frog, some that use other toxins and some that use none at all. They then sequenced a gene responsible for encoding a particular receptor, the same involved in pain and nicotine addiction in humans, and built an evolutionary tree demonstrating how the gene had evolved to shield the frog from its owns toxins.

Toxins found in some frogs, such as the phantasmal poison frog, could hold important lessons for pain relief in humans
Toxins found in some frogs, such as the phantasmal poison frog, could hold important lessons for pain relief in humans

The team identified a small genetic mutation, which changed just three of the 2,500 amino acids making up the receptor, which stops the toxin from binding to it, in effect making the frog immune to its effects. And while these frogs have developed the capability to block the toxin, the receptors otherwise work in the normal, healthy way. Better understanding this process may hold invaluable lessons for scientists developing drugs that block pain and nicotine addiction, without adverse side effects.

"Every bit of information we can gather on how these receptors are interacting with the drugs gets us a step closer to designing better drugs," said Cecilia Borghese, a research associate at the University of Texas' Waggoner Center for Alcohol and Addiction Research and co-first author of the study.

The team has published its research in the journal Science.

Source: University of Texas at Austin

2 comments
ljaques
FORGET drugs, whose costs are borne -only- by US citizens, to our great chagrin. And whose side-effects can also kill. Give us a way to quickly evolve receptors so we can become pain-free beings, please! Many of my pain issues were food allergies, so I've been able to reduce problems a great deal, but some remain. Please put this on the top burner, folks! Thanks.
noteugene
Oh cool, either new receptors or a new drug.