Researchers at the University of Queensland found that toxins from the ongaonga nettle activate pain receptors in a new way compared to other nettles they were familiar with.
The tree nettle is one of New Zealand’s most poisonous plants, causing stings that can last for days.
The stinging nettles can grow up to 3 meters in height and are usually quickly removed from gardens and paddocks, despite being an essential food for the caterpillar of the beloved native red admiral butterfly, which lays its eggs on the plants, and is believed to decay.
A researcher for the study, Dr. Sam Robinson, said the tree may have evolved its strong stinging toxin to ward off hungry moa.
“We found that the New Zealand nettle tree toxins target the same receptor as their Australian counterparts, but they cause pain in a different way.
“The Australian stinging nettle and New Zealand stinging nettle are both members of the stinging nettle family, but they separated millions of years ago and evolved differently.”
Director of the university’s Center for Pain Research, Irina Vetter, said studying different mechanisms that plants use to hurt the human body could help scientists better understand pain pathways, which could give them clues to develop pain pathways. better medicines to control pain.
“Animal venom has been studied for decades, but plants have evolved toxins differently, and this gives us the opportunity to find molecules that work in a unique way,” she said.
“Our goal is to manage pain more effectively, without side effects and addiction.”
International travel restrictions due to Covid-19 initially made it difficult for the Queensland team to obtain ongaonga, but they were able to obtain seeds from New Zealand and grow the plant in quarantine in a lab.
They now plan to expand the study to look at how stings are inflicted by other nettles from different countries.
“There are hundreds of stinging nettles in the Urticaceae family of stinging hairs around the world — we’d like to compare how they evolved and whether they all use the same toxins,” said Dr Edward Gilding, another researcher on the stinging nettle project.
They are now planning trips to Vietnam, Madagascar and South America to examine more diverse nettle examples.
The research is published in the Journal of Biological Chemistry.
Ongaonga or New Zealand nettle is covered with spines that cause a painful sting when someone strokes it.