Researchers from the Universities of Bonn and Mainz have discovered a previously unknown function of the cannabinoid-1 receptor (CB1): it can protect against aging processes.

Cannabinoids, such as THC (the active agent in Cannabis sativa) and endocannabinoids, and those formed by the body bind to the CB1 receptors. The existence of this receptor is also the reason for the intoxicating effect of hashish and marijuana, the researchers said.

The researchers studied mice in different age categories. They mice had to find a submerged platform in the pool. Once they knew its location, the platform was moved, and the animals had to find it again.

The animals in which the CB1 receptor had been switched off genetically (the “knock-out mice”) showed clearly diminished learning and were less successful in their search for the platform. In addition, they showed a clear loss of nerve cells in the hippocampus, the researchers said.

“If we switch off the receptor using gene technology, mouse brains age much faster,” said Önder Albayram, principal author of the publication and a doctoral student on the team of Professor Dr. Andreas Zimmer from the Institut für Molekulare Psychiatrie at the University of Bonn. “This means that the CB1 signal system has a protective effect for nerve cells.”

Ref.: A. Bilkei-Gorzo, et al., Role of CB1 cannabinoid receptors on GABAergic neurons in brain aging, PNAS, 2011; 108 (27): 11256 [DOI: 10.1073/pnas.1016442108]