Cats love catnip because it protects them from mosquitoes, new research finds

When exposed to catnip or silver vines, cats exhibit fairly predictable behaviors, such as licking and chewing leaves, rubbing their head and face against plants, and rolling on the ground. Cats really enjoy these plants, but surprising new research points to a more practical goal than just wanting to get high.

Nepetalactol – the most potent active ingredient in catnip (Nepeta cataria) and silver vine (Actinidia polygama) – provides cats with chemical defense against mosquitoes, news says research published in Science Advances. The discovery could explain why felines, whether domestic cats or large jungle predators, display similar behaviors after being exposed to these plants.

The new research, led by Masao Miyazaki of Iwate University in Japan, offers new insight into nepetalactol and how it affects the behavior of felines and their opioid receptors. This nepetalactol deters mosquitoes is a startling revelation, and it could give rise to a whole new class of insect repellant, researchers say. Nepetalactol had previously been linked to mosquito repellent activity, but “our data is the first to show it,” Miyazaki explained in an email.

In addition, the new article is the “first to show that nepetalactol is a potent bioactive compound for cats”. Indeed, it is no secret that the chemical has some kind of neurological effect on cats, but catnip, a plant in the mint family, and silver vine, a kind of kiwi, contain a plethora of other bioactive compounds, such as isoiridomyrmecine, iridomyrmecine, isodihydronepetalactone and dihydronepetalactone. Miyazaki and his colleagues, including researchers from Nagoya University in Japan and the University of Liverpool in the UK, focused on nepetalactol because of its suspected potency.

After coming into contact with catnip and silver vines, cats engage in stereotypical behaviors, such as rubbing their head and face against plants, rolling on the ground, and appearing euphoric. It lasts about five 15 minutes away and is followed by the crash phase, in which the cats rest for about an hour or more. The effect of these plants on cats has been known for centuries, but scientists don’t fully understand the purpose of all of this, as a biological or evolutionary reason – assuming it is. not just some bizarre coincidence having to do with the feline brain.

For more information, the team studied a group of different felines, including 25 lab cats, 30 feral cats, and several captive big cats, including leopards, jaguars and lynxes. They documented cats’ reactions filter paper laced with nepetalactol. Ahe will cats exhibited the classic behavioral response. reogs and mice exposed chemical presented no response.

Scientists also studied cat reactions to some of the other bioactive agents found in silver vine and found nepetalactol is the most potent.

“This study found that … nepetalactol is the major bioactive compound found in silver grape leaves that induces characteristic friction and rolling in cats,” the authors write in their study. “In addition, nepetalactol had similar bioactivity in the Amur leopard, jaguar and Eurasian lynx. Like most [feline] species tested so far have shown positive responses to catnip (13 of 21 species tested out of a total of 41 living species of this family), it is likely that this characteristic response to nepetalactol will also be common to many [felines]. “

The group also measured the cats’ endorphin levels before and after exposure, finding that the feline reaction to nepetalactol is regulated by their opioid system; elevated endorphins levels were only observed after exposure to nepetalactol. Additionally, when scientists suppressed their opioid receptors with special drugs, cats no longer showed their characteristic behaviors when exposed to the chemical.

As for silver vine’s role as a mosquito repellant, the researchers found that thisthe hairs covered with nepetalactol attracted far fewer mosquitoes, especially the species A. albopictus, that the untreated control group—in some cases, up to half.

“These results show that nepetalactol, transferred to the fur of the face and head by rubbing against the silvery grape leaves, acts as a repellent against A. albopictus in cats ”, write the authors. “This is convincing evidence that the characteristic friction and rolling response works to transfer chemicals from plants that provide mosquito repellency to cats.”

This, according to the authors, could explain why the behavior evolved. Cats get high on these plants, roll around in the leaves, and unwittingly protect themselves against mosquitoes. This theory makes a lot of sense, but scientists now have to explain why this behavior is not seen in other animals, and whether the repellant action actually occurs in nature, not just in a lab. We also need to know if nepetalactol works to regrow A. aegypti, the mosquito responsible for the spread of yellow fever, dengue fever and Zika virus.

Miyazaki said there could be a very good reason why felines developed this special relationship with Catnip and Silver Vine. Many felines “rely on stealth to stalk and ambush their prey,” forcing them to remain silent and still, he said. A repellant which “reduces their susceptibility to both irritation from biting mosquitoes and to diseases carried by these insect vectors is likely to provide a strong selective advantage”. This explains why this characteristic has been retained by many species of cats, but it “does not explain why behavior has only evolved in felines,” Miyazaki said.

One possible explanation is that an ancestor of modern cats developed special olfactory receptors, which Perhaps it was a “crucial pre-adaptation” that gave the opportunity for this behavior to evolve, Miyazaki speculated.

For the future, the team wishes to identify the olfactory receptors linked to nepetalactol, as well as the genes responsible for behavior. Miyazaki said team members tested nepetalactol on their arms and it appeared to repel mosquitoes. But this “relates only to patent data,” he said.

Ah yes, the almighty dollar. But it’s a where good science could lead to a good and welcome commercial product. Indeed, researchers may have stumbled upon a new type of mosquito repellant, but time will tell if it works better than conventional repellents. and whether it is economically and practical to synthesize this compound in large quantities.