Summary: Cannabis use in children may lead to thinning of the cerebral brain, a crucial mental area for mental performance. Scientists found that THC, the active ingredient in hemp, causes the receding of neurons, which are important for nerve interaction.
This atrophy does change the brain’s ability to learn, deal, and converse politically, increasing risk during a crucial period of brain development. The researches emphasize the need for more research into how cannabis affects adolescent mental development.
Important Information:
- THC in hemp causes a thinning of the cortical brain in young people.
- Dendrites, necessary for neuron communication, reduce according to cannabis use.
- This drying may impede learning, social conversation, and coping abilities.
Origin: University of Montreal
Cannabis usage may lead to drying of the cortical brain in children according to a recent investigation led by , Graciela Pineyro , and , Tomas Paus,, experts at CHU Sainte-Justine and professors at the Université de Montréal Faculty of Medicine.  ,
A collaborative effort between two research laboratories with comparable approaches, the research demonstrates that THC – or tetrahydrocannabinol, an active element in cannabis – causes deformation of the terminal arborization, neurons ‘ “network of antennae” whose function is essential for connection between neurons.
At a time when the mind is developing, some areas of the cerebral cortex are atrophying as a result.  ,  ,  ,
” If we take the comparison of the mind as a laptop, the neurons would be the main computer, receiving all information via the synapses through the dendritic network”, explains Tomas Paus, who is also a professor of psychiatry and neuroscience at Université de Montréal.
” So a decrease in the data input by dendrites makes it more difficult for the brain to learn new things, communicate with others, deal with new situations, etc.,” according to the statement. In other words, it makes the brain more prone to everything that can occur in a young person’s life.
A multi-level approach to better comprehend the impact on people
This project is notable for the complementary, multi-level nature of the methods used.
We already discovered that young people who used cannabis before the age of 16 had a thinner cerebral cortex by analyzing magnetic resonance imaging ( MRI ) scans of a cohort of teenagers, according to Tomas Paus.
” However, this research method does n’t allow us to draw any conclusions about causality, or to really understand THC’s effect on the brain cells”.  ,
The development of the mouse model by Graciela Pineyro’s team was crucial given the limitations of MRI.
Graciela Pineyro, a professor in the Department of Pharmacology and Physiology at the Université de Montréal, claims that the model allowed it to demonstrate that THC modifies the expression of some genes that affect the function and structure of synapses and dendrites.
The result is” a dendritic arborescence atrophy that could explain the thinning observed in some of the cortex’s regions.”
Interestingly, these genes were also found in humans, particularly in the thinner cortical regions of the cohort adolescents who experimented with cannabis.
The two teams were able to ascertain with a high degree of certainty that the genes targeted by THC in the mouse model were also related to the cortical thinning observed in adolescents by combining their distinct research methods.  ,
It’s crucial that we improve our understanding of how cannabis use affects brain maturation and cognition, especially with commercial cannabis products containing increasing amounts of THC.
This cutting-edge collaboration study, which incorporated cutting-edge methods in cellular and molecular biology, imaging, and bioinformatics analysis, is a step in the right direction for the creation of effective public health measures.
About this news about neurodevelopment and CUD
Author: Julie Gazaille
Source: University of Montreal
Contact: Julie Gazaille – University of Montreal
Image: The image is credited to Neuroscience News
Original Research: Closed access.
” Cells and Molecules Underpinning Cannabis-Related Variations in Cortical Thickness during Adolescence” by Graciela Pineyro et al. Journal of Neuroscience
Abstract
Cells and Molecules Underpinning Cannabis-Related Variations in Cortical Thickness during Adolescence
During adolescence, cannabis experimentation is common, and its association with interindividual variations in brain maturation well studied. Cellular and molecular underpinnings of these system-level relationships are, however, unclear. We thus conducted a three-step study.
First, we exposed adolescent male mice to Δ-9-tetrahydrocannabinol ( THC ) or a synthetic cannabinoid WIN 55, 212-2 ( WIN ) and assessed differentially expressed genes ( DEGs ), spine numbers, and dendritic complexity in their frontal cortex. Second, in human ( male ) adolescents, we examined group differences in cortical thickness in 34 brain regions, using magnetic resonance imaging, between those who experimented with cannabis before age 16 ( n = 140 ) and those who did not ( n = 327 ).
Finally, we correlated these group differences spatially with gene expression of mouse-identified DEGs that were human homologs. The spatial expression of 13 THC-related human homologs of DEGs correlated with cannabis-related variations in cortical thickness, and virtual histology revealed coexpression patterns of these 13 genes with cell-specific markers of astrocytes, microglia, and a type of pyramidal cells enriched in dendrite-regulating genes.
In the same way, the spatial expression of 18 DEG-related WINs was related to differences in cortical thickness across groups and revealed coexpression patterns across all three cell types.
According to gene ontology analysis, 33 WIN-related homologs are more abundant in learning and memory processes, while 37 THC-related homologs are more abundant in neuron projection development.
In mice, we observed lower dendritic complexity and spine loss in pyramidal cells from controls and animals exposed to THC. Glutamatergic synapses and dendritic arborization may be affected by cannabis use during adolescence by influencing cortical thickness.
