How’s this for hilariously depressing: male fruit flies who have their sexual advances rejected drink alcohol far more heavily than males who are regularly having sex.
Yes, you read that right. New research from a team at UC San Francisco has discovered that a tiny molecule in flies’ brains, called neuropeptide F, acts as a link between sexual rejection and excessive drinking. A similar molecule, neuropeptide Y, exists in humans, and as such the research helps shed light on what triggers human addiction.
“If neuropeptide Y turns out to be the transducer between the state of the psyche and the drive to abuse alcohol and drugs, one could develop therapies to inhibit neuropeptide Y receptors,” UCSF professor Ulrike Heberlein, who led the research, said in a release.
The paper, published this week in Science, outlines just how the researchers set up an experimental fruit fly nightclub. Male flies were placed in a container with either virgin females or females that had already mated. Oddly enough, a substance injected by male flies along with their sperm makes females reject the loving passes of other guys.
What’s really goofball is that rejected males apparently lose all of their confidence, and quit trying to mate, even when placed back with willing virgin females. Not only did they give up on women, they hit the booze hard: The team placed the jilted males into a container with a pair of straws, one with food and one with food mixed with 15 percent (30 proof) alcohol.
The flies who struck out unfailingly favored the booze, while males that had succeeded in getting it on were less likely to touch the sauce. A fly’s choice of hooch or not was not only correlated with its sexual success, but also the levels of neuropeptide F in its brain, which the team found fluctuated based on whether or not the fly was getting laid.
The team confirmed the correlation between neuropeptide F and binge drinking by artificially manipulating neuropeptide F levels in the flies’ brains. When they took flies that had given up on women and increased their amounts of neuropeptide F, the former drunks voluntarily quit drinking. The opposite happened as well: a fly Adonis had his neuropeptide F levels artificially lowered, he immediately began hitting the bottle like one of his depressed, lonely colleagues.
Apparently, getting blackfaded is pretty common for lab-based flies; the report mentions that flies will normally drink “to intoxication” if given the chance. But male flies who’d had a lot of success with the fairer sex – and thus had higher levels of neuropeptide F in their brains – drank less. In other words, flies who were happily mating were less likely to seek out other rewarding experiences.
That correlation, based on neuropeptide levels, may translate to humans, where we may connecting socially rewarding experiences with binge drinking. Additionally, lower levels of neuropeptide Y have been found in people battling depression and PTSD.
Could manipulating neuropeptide Y in humans help cure addiction? Well, the authors suggest it’s possible, but extremely difficult as the molecule is spread all throughout our sensitive brains. So, while the paper doesn’t offer a cure-all for depressed binge-drinking, it does offer one rock-solid conclusion: a genetic-research themed club called BarFlies would kick ass.
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