14 DAY TRIAL // A team of investigators from The Scripps Research Institute (SRI) announces the discovery of a neural pathway that dictates precisely how susceptible an individual is of getting hooked on the addictive properties of nicotine.
According to the new study, the mechanism the team identified in the human brain could soon be used as a new target for anti-smoking therapies. This could help make it a lot easier for people who smoke to quit the habit.
Details of the new investigation appear in the January 30 advanced online issue of the esteemed scientific journal Nature, Science Blog reports. In the new paper, experts showcase the methodology they used, and the full conclusions they arrived at.
One of the main focuses of the new investigation was analyzing a subunit pertaining to a receptor that gets activated as nicotine makes its way into the brain. This receptor is in fact a simple protein to which signaling molecules from the tobacco attach.
In experiments they conducted on unsuspecting lab animals, the researchers discovered that inducting genetic mutations in this subunit resulted in the receptor binding to a lot more nicotine than normal.
Conversely, if the subunit's expression patterns were boosted, the receptor as a whole bound to far less nicotine, the research team says.
“We believe that these new data establish a new framework for understanding the motivational drives in nicotine consumption and also the brain pathways that regulate vulnerability to tobacco addiction,” explains scientist Paul Kenny.
“These findings also point to a promising target for the development of potential anti-smoking therapies,” adds the study leader, who is also an associate professor at the Scripps Research Institute.
The structure the team looked at is located in the habenulo-interpeduncular tract, and is called the nicotinic receptor subunit α5.
“It was unexpected that the habenula, and brain structures into which it projects, play such a profound role in controlling the desire to consume nicotine,” says the first author of the study, Christie Fowler.
“The habenula appears to be activated by nicotine when consumption of the drug has reached an adverse level. But if the pathway isn’t functioning properly, you simply take more,” she says.
“Our data may explain recent human data showing that individuals with genetic variation in the α5 nicotinic receptor subunit are far more vulnerable to the addictive properties of nicotine,” adds the expert, who is also a research associate in the Kenny laboratory. “
They may also help explain why variations in the subunit are “far more likely to develop smoking-associated diseases such as lung cancer and chronic obstructive pulmonary disease,” Fowler concludes, quoted by Science Blog.