Cannabis use linked to thinning cerebral cortex in adolescents

Hashish use might result in thinning of the cerebral cortex in adolescents in response to a current examine led by Graciela Pineyro and Tomas Paus, researchers at CHU Sainte-Justine and professors on the Université de Montréal College of Medication. A collaborative effort between two analysis laboratories with complementary approaches, the examine demonstrates that THC – or tetrahydrocannabinol, an energetic substance in hashish – causes shrinkage of the dendritic arborization, neurons’ “community of antennae” whose function is crucial for communication between neurons. This ends in the atrophy of sure areas of the cerebral cortex – unhealthy information at an age when the mind is maturing. 

If we take the analogy of the mind as a pc, the neurons can be the central processor, receiving all data by way of the synapses via the dendritic community. So a lower within the knowledge enter to the central processor by dendrites makes it more durable for the mind to study new issues, work together with folks, deal with new conditions, and many others. In different phrases, it makes the mind extra weak to every little thing that may occur in a teenager’s life.”

Tomas Paus, professor of psychiatry and neuroscience, Université de Montréal

A multi-level method to higher perceive the impact on people

This challenge is notable for the complementary, multi-level nature of the strategies used. “By analyzing magnetic resonance imaging (MRI) scans of the brains of a cohort of youngsters, we had already proven that younger individuals who used hashish earlier than the age of 16 had a thinner cerebral cortex,” explains Tomas Paus. “Nevertheless, this analysis methodology does not permit us to attract any conclusions about causality, or to essentially perceive THC’s impact on the mind cells.” 

Given the constraints of MRI, the introduction of the mouse mannequin by Graciela Pineyro’s workforce was key. “The mannequin made it doable to display that THC modifies the expression of sure genes affecting the construction and performance of synapses and dendrites,” explains Graciela Pineyro, who can also be a professor within the Division of Pharmacology and Physiology at Université de Montréal. “The result’s atrophy of the dendritic arborescence that might contribute to the thinning noticed in sure areas of the cortex.” 

Apparently, these genes had been additionally present in people, notably within the thinner cortical areas of the cohort adolescents who experimented with hashish. By combining their distinct analysis strategies, the 2 groups had been thus in a position to decide with a excessive diploma of certainty that the genes focused by THC within the mouse mannequin had been additionally related to the cortical thinning noticed in adolescents. 

With hashish use on the rise amongst North American youth, and business hashish merchandise containing rising concentrations of THC, it is crucial that we enhance our understanding of how this substance impacts mind maturation and cognition. This profitable collaborative examine, involving cutting-edge strategies in mobile and molecular biology, imaging and bioinformatics evaluation, is a step in the fitting path for the event of efficient public well being measures.