Tetrahydrocannabinol (THC) improves motor and memory deficits in a sporadic Alzheimer-model

Introduction:

The endocannabinoid system (ECS) is connected to several processes of the human body and has among others neuroprotective and anti-inflammatory functions. Cannabinoid-receptors are expressed on pre-synaptic neurons as well as on cells belonging to the immune system. THC is a partial agonist on both cannabinoid-receptors, therefore influencing the ECS with THC could be beneficial for the treatment of Alzheimer's-Disease (AD).

Material and Methods:

In our current project, transgenic Alzheimer-mice (Tg4 – 42) as well as wildtype-mice were injected daily with 100 mg/kg THC for 6 weeks (n = 12 per group). Tg4 – 42 mice express intraneuronal N-truncated Abeta and represent the sporadic form of AD. To analyze the effects of THC motoric as well as memory tests were performed. The Rotarod-test was used to evaluate motoric learning. The Morris-Water-Maze was used to study spatial learning and memory.

Results and Conclusion:

The Rotarod-test showed a significant improvement in motoric learning of THC-treated Tg4 – 42 compared to the placebo-treated mice. Furthermore, THC-treated Tg4 – 42 showed an improved short- and long-term memory in the Morris-Water-Maze.

In summary our results show that chronically THC treatment improves motor and memory deficits in AD mice. Our findings suggest that THC may have therapeutic potential as a treatment for AD patients.

This study was supported by DFG Exzellenzcluster CNMPB 'Mikroskopie im Nanometerbereich und Molekularphysiologie des Gehirns'.