The problem with mosquitoes (besides the fact that they bite) is that they just don’t quit, pestering their target over and over again until they’ve had their fill. But suppose there could be a way to satisfy the appetites of mosquitoes before they attack? Researchers at Rockefeller University in New York City believe this might be the case.
If you’ve ever wondered why mosquitoes are so attracted to humans, well, here’s a quick explanation. As disturbing as it might sound, mosquitoes view humans as a source of food. The reason for this is that our blood contains a type of protein that female mosquitoes use to make their eggs. After these insects have extracted all the blood they need, their food cravings all but evaporate – until they get hungry again.
For their study, the Rockefeller University team sought to find an alternative way to satiate these mosquito’s appetites. To accomplish this, the researchers concocted a saline solution designed to activate mosquito neuropeptide Y (NPY) receptors. As in humans, these NPY receptors regulate mosquito food intake. When they activate, the desire to eat rapidly vanishes.
Modern anti-obesity drugs attempt to curb food cravings by targeting NPY receptors, stimulating them and thereby making food appear much less appealing. It was this substance that the authors placed in the solution fed to their mosquitoes. The insects’ attraction to human subjects was measured using a piece of nylon stocking, which had been worn for a sustained period of time by senior author Laura Duvall. If they were still hungry, the mosquitoes would pick up the bodily odors given off by the nylon, and subsequently head towards the clothing. If not, they would simply ignore the scent.
Finding the Off Switch
Sure enough, the mosquitoes acted as if they were full, showing little interest in the nylon. Conversely, after consuming blood samples with NPY-inhibiting drugs, the insects were far more attracted to the nylon stocking piece. The revelations did not end there; further testing revealed the exact identity of the receptor that managed mosquito appetite – NPYLR7.
In light of this finding, the authors attempted to identify a molecule that would trigger NPYLR7 receptors in mosquitoes, while simultaneously leaving humans untouched. Upon sorting through a list of 250,000 possible substances, the research team found a molecule that fit the bill perfectly, one they dubbed “compound 18.” It may be possible for future studies to outline a way to further develop compound 18, allowing it to be used in mosquito traps placed in the wild. The Rockefeller University report appeared in the Journal of Cell Biology.