Alzheimer's disease; taking the edge off with cannabinoids?
Article first published online: 29 JAN 2009
2007 British Pharmacological Society
British Journal of Pharmacology
Special Issue: Special Issue: Cannabinoid Pharmacology
Volume 152, Issue 5, pages 655–662, November 2007
How to Cite
Campbell, V. A. and Gowran, A. (2007), Alzheimer's disease; taking the edge off with cannabinoids?. British Journal of Pharmacology, 152: 655–662. doi: 10.1038/sj.bjp.0707446
- Issue published online: 29 JAN 2009
- Article first published online: 29 JAN 2009
- (Received May 29, 2007, Revised July 3, 2007, Accepted August 8, 2007)
- Alzheimer's disease;
- CB1 receptor;
- CB2 receptor;
Alzheimer's disease is an age-related neurodegenerative condition associated with cognitive decline. The pathological hallmarks of the disease are the deposition of β-amyloid protein and hyperphosphorylation of tau, which evoke neuronal cell death and impair inter-neuronal communication. The disease is also associated with neuroinflammation, excitotoxicity and oxidative stress. In recent years the proclivity of cannabinoids to exert a neuroprotective influence has received substantial interest as a means to mitigate the symptoms of neurodegenerative conditions. In brains obtained from Alzheimer's patients alterations in components of the cannabinoid system have been reported, suggesting that the cannabinoid system either contributes to, or is altered by, the pathophysiology of the disease. Certain cannabinoids can protect neurons from the deleterious effects of β-amyloid and are capable of reducing tau phosphorylation. The propensity of cannabinoids to reduce β-amyloid-evoked oxidative stress and neurodegeneration, whilst stimulating neurotrophin expression neurogenesis, are interesting properties that may be beneficial in the treatment of Alzheimer's disease. Δ9-tetrahydrocannabinol can also inhibit acetylcholinesterase activity and limit amyloidogenesis which may improve cholinergic transmission and delay disease progression. Targeting cannabinoid receptors on microglia may reduce the neuroinflammation that is a feature of Alzheimer's disease, without causing psychoactive effects. Thus, cannabinoids offer a multi-faceted approach for the treatment of Alzheimer's disease by providing neuroprotection and reducing neuroinflammation, whilst simultaneously supporting the brain's intrinsic repair mechanisms by augmenting neurotrophin expression and enhancing neurogenesis. The evidence supporting a potential role for the cannabinoid system as a therapeutic target for the treatment of Alzheimer's disease will be reviewed herewith.
British Journal of Pharmacology (2007) 152, 655–662; doi:10.1038/sj.bjp.0707446; published online 10 September 2007