New Research Shows How Cannabis Can Potentially Influence Brain Development

New Research Shows How Cannabis Can Potentially Influence Brain Development

Amsterdam UMC’s Neuroscientist Rogier Min has collaborated with Christiaan Levelt’s lab from the Netherlands Institute for Neuroscience and discovered how brain cells may react to Cannabis and its potential impact on our brain’s flexibility.

According to reports, Cannabis binds, also called Cannabinoid receptor 1 (CB1 receptor), is one of the most common receptors in the human brain. CB1 receptors function as switches that can turn various biological processes on or off.

This was thought to have been situated only on nerve cells (neurons), but the team has shown that another is involved – astrocytes. According to reports, Astrocytes, a type of glial cell in the brain and spinal cord, proved this wrong.

The team studied the dynamics of Astrocytes’ important role in the brain’s development, especially in one’s earlier years.

This study exposed the team to the different phases of brain development, such as plasticity, also known as the critical period – how the brain adjusts and changes.

Levelt says, “In earlier studies from the 80s, researchers injected astrocytes from a kitten into the visual cortex of an older cat, the brain area involved in vision.

As a result, the critical period was opened again, meaning the brain could adjust more easily again. We also know that the CB1 receptor in astrocytes is expressed less and less as we age.

Could there be a link here? And could this mean that the CB1 receptor on astrocytes plays a role in this critical period plasticity?”

To ascertain results, the team tested the CB1 receptor and astrocytes to gain deeper knowledge of how they influence the development of the inhibitory system in the brain.

The brain consists of both stimulating and inhibitory nerve cells. We need the inhibitory cells, interneurons, to balance our brain activity. This study focused on the visual cortex, the part of the brain that helps us process what we see.

Min says, “We found this by temporarily covering the eye of a young mouse during the critical period for vision. In normal mice, their brain can adapt by strengthening the connection to the ‘good eye.’

“Mice without CB1 receptors on the interneurons seemed to follow a similar adaptability as the control mice. However, this adaptability didn’t work effectively in mice without CB1 receptors on the astrocytes.

These findings show that astrocytes in particular, and not nerve cells, play an important role in this process, which is surprising.”

Aside from offering a better understanding of how the brain develops, the research can also help explain how cannabis use at a younger age can introduce some risks.

Studies looking at the long-term effects of Cannabis on the brain are not conclusive.

However, there are indicators that if the CB1 receptor is disturbed during brain development, there may be problems with learning, memory, or other brain functions.

While young children usually don’t use Cannabis, teenagers and young adults are a particular risk group. Their brains are still developing, especially the prefrontal cortex, which is involved in planning and decision-making.

Min says, “The CB1 receptor is involved in numerous processes in the brain. It’s actually extraordinary that the binding of Cannabis to the CB1 receptor doesn’t typically result in big problems.

Our research could explain some negative consequences of Cannabis: the CB1 receptor on astrocytes appears to be an important player in early brain development, and disrupting this process can impact the amount that our brain can adjust.

“While Cannabis is often seen as relatively safe, it can still influence brain development at younger ages. Now we have a slightly better impression of how and why that happens.”