Archive for the ‘Multiple Sclerosis’ Category

Over the last decade, the endocannabinoid system (ECS) has emerged as a potential target for multiple sclerosis (MS) management. A growing amount of evidence suggests that cannabinoids may be neuroprotective during CNS inflammation. Advances in the understanding of the physiology and pharmacology of the ECS have potentiated the interest of several components of this system as useful biological targets for disease management. Alterations of the ECS have been recently implicated in a number of neuroinflammatory and neurodegenerative conditions, so that the pharmacological modulation of cannabinoid (CB) receptors and/or of the enzymes controlling synthesis, transport, and degradation of these lipid mediators is considered an option to treat several neurological diseases. This chapter focuses on our current understanding of the function of anandamide (AEA), its biological and therapeutic implications, as well as a description of its effects on neuroimmune modulation.

Cannabinoids have been reported to alter the activities of immune cells in vitro and in vivo. These compounds may serve as ideal agents for adjunct treatment of pathological processes that have a neuroinflammatory component. As highly lipophilic molecules, they readily access the brain. Furthermore, they have relatively low toxicity and can be engineered to selectively target cannabinoid receptors. To date, two cannabinoid receptors have been identified, characterized and designated CB₁ and CB₂. CB₁ appears to be constitutively expressed within the CNS while CB₂ apparently is induced during inflammation. The inducible nature of CB₂ extends to microglia, the resident macrophages of the brain that play a critical role during early stages of inflammation in that compartment. Thus, the cannabinoid-cannabinoid receptor system may prove therapeutically manageable in ablating neuropathogenic disorders such as Alzheimer’s disease, multiple sclerosis, amyotrophic lateral sclerosis, HIV encephalitis, closed head injury, and granulomatous amebic encephalitis.Keywords: Alzheimer’s, amyotrophic lateral sclerosis, cannabinoids, cannabinoid receptors, granulomatous amebic encephalitis, HIV encephalitis, multiple sclerosis, neuroinflam

Marijuana derivatives or “cannabinoids” taken for one year for the treatment of multiple sclerosis (MS) may reduce muscle spasms and other aspects of disability, results of a UK study suggest.

Dr. J. P. Zajicek, from Peninsula Medical School in Plymouth and colleagues previously reported that cannabinoids taken for 14 weeks appeared to improve mobility and patients’ perception of their MS symptoms. In an extension study, 80 percent of subjects agreed to continue on the medication for up to 52 weeks. The results are reported in the Journal of Neurology, Neurosurgery and Psychiatry.

The analysis included more than 500 patients who were randomly assigned to receive various cannabinoids or an inactive “placebo.”

Treatment with delta-9-THC, a synthetic cannabinoid, seemed to relieve muscle spasms. In addition, patients treated with this drug and other cannabinoids reported improvements in sleep and pain.

Zajicek’s group concludes that “there is now an urgent need to construct a long-term study in progressive MS to establish whether delta-9-THC has a role in long-term disease.”

Dr. J. Killestein and Dr. B. M. J. Uitdehaag, writing in a related editorial, agree with Zajicek’s team about the need for more long-term trials.

The editorialists, from VU Medical Centre in Amsterdam, the Netherlands, add that “these trials should also focus on different cannabinoid products.”

SOURCE: Journal of Neurology, Neurosurgery and Psychiatry, December 2005.