Cocaine and Nicotine Create Stronger Connection to Dopamine in Teen's Brains Making Them More at Risk to Substance Abuse, Study Reveals

A previous study at Yale University discovered that drug addiction is considered a developmental disorder that specifically affects adolescents. It is caused by undeveloped part of the brain which is responsible for impulse control, and the part which boosts drug use is already fully formed.

How do drugs affect the development of a teenage brain has been an ongoing question scientists encounter. Scientists explained the answer saying that teens are more at risk for addiction because they are usually exposed in situations where they are more likely to concede to whatever their peer is doing. However, according to eLife, there might be reason to believe that teen addiction is caused by something biological.

Another study also revealed that scientists usually use biology to explain alcohol abuse in teens but has not been commonly used to rationalize drug addiction. "In humans, adolescence, namely the period between the early teenage years and early twenties, is a time of heightened susceptibility to the effects of addictive drugs, but previous studies have struggled to explain why," said senior author Mauro Cosa-Mattioli, in a press release. "Our studies support the idea that regulation of protein synthesis by eIF2 might be the underlying cause."

According to medicaldaily.com, the studies examine the role elF2 α play, which is responsible for the regulation of the production of proteins needed for the connection of neurons. In one study, adolescent and adult mice were injected with a saline solution or a low dose of cocaine. The team observed that the adolescent mice which received cocaine experienced a decrease in eIF2α that resulted in protein regulation changes and strengthened the connections between dopamine-storing neurons.

The research team was also able to confirm their results by changing the number of proteins produced controlled by eIF2α in adult and adolescent mice. The effect was adult mice biologically became adolescent and vice versa. Through that process, the researchers were able to witness changes in the result from the first part of the study.

"This greater communication between dopamine-rich neurons gives a greater sense of pleasure from taking the drug and encourages behaviors related to addiction," said lead author Wei Huang. "Only higher doses of cocaine led to similar responses in adult mice, proving that adolescents have a lower threshold for the effects of cocaine on these neurons."

Now, adolescent mice which have adult protein structures in them showed no changes in the activity of elF2 α, and were more resistant to cocaine, while the adult mice which had adolescent protein structures in them became more sensitive.