Stimulation of cannabinoid receptor 2 (CB2) suppresses microglial activation

“Activated microglial cells have been implicated in a number of neurodegenerative disorders, including Alzheimer’s disease (AD), multiple sclerosis (MS), and HIV dementia. Many data reveal that cannabinoids mediate suppression of inflammation in vitro and in vivo through stimulation of cannabinoid receptor 2 (CB2).

Taken together, these results provide mechanistic insight into beneficial effects provided by cannabinoid receptor CB2 modulation in neurodegenerative diseases, particularly AD.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1352348/

Does Smoking Marijuana Prevent Alzheimer’s Disease?

“Maintaining Memories with Marijuana. Research in my laboratory has demonstrated that stimulating the brain’s marijuana receptors may offer protection by reducing brain inflammation and by restoring neurogenesis. Thus, later in life, marijuana might actually help your brain, rather than harm it.

It takes very little marijuana to produce benefits in the older brain; my colleague in France, Dr. Yannick Marchalant, coined the motto “a puff is enough” because it appears as though only a single puff each day is necessary to produce significant benefit.

The challenge for pharmacologists in the future will be to isolate the beneficial effects of the marijuana plant from its psychoactive effects.”

http://www.theweedblog.com/does-smoking-marijuana-prevent-alzheimers-disease/

Endocannabinoid system: emerging role from neurodevelopment to neurodegeneration.

“The endocannabinoid system, including endogenous ligands (‘endocannabinoids’ ECs), their receptors, synthesizing and degrading enzymes, as well as transporter molecules, has been detected from the earliest stages of embryonic development and throughout pre- and postnatal development. ECs are bioactive lipids, which comprise amides, esters and ethers of long chain polyunsaturated fatty acids. Anandamide (N-arachidonoylethanolamine; AEA) and 2-arachidonoylglycerol (2-AG) are the best studied ECs, and act as agonists of cannabinoid receptors.

Thus, AEA and 2-AG mimic several pharmacological effects of the exogenous cannabinoid delta9-tetrahydrocannabinol (Delta(9)-THC), the psychoactive principle of cannabis sativa preparations like hashish and marijuana. Recently, however, several lines of evidence have suggested that the EC system may play an important role in early neuronal development as well as a widespread role in neurodegeneration disorders. Many of the effects of cannabinoids and ECs are mediated by two G protein-coupled receptors (GPCRs), CB1 and CB2, although additional receptors may be implicated. Both CB1 and CB2 couple primarily to inhibitory G proteins and are subject to the same pharmacological influences as other GPCRs. This new system is briefly presented in this review, in order to put in a better perspective the role of the EC pathway from neurodevelopment to neurodegenerative disorders, like Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and multiple sclerosis.

In addition, the potential exploitation of antagonists of CB1 receptors, or of inhibitors of EC metabolism, as next-generation therapeutics is discussed.”

http://www.ncbi.nlm.nih.gov/pubmed/19356123

Cannabidiol and other cannabinoids reduce microglial activation in vitro and in vivo: relevance to Alzheimer’s disease.

“Microglial activation is an invariant feature of Alzheimer’s disease (AD). It is noteworthy that cannabinoids are neuroprotective by preventing β-amyloid (Aβ)-induced microglial activation both in vitro and in vivo… the phytocannabinoid cannabidiol (CBD) has shown anti-inflammatory properties in different paradigms…

Cannabinoids, whether plant-derived, synthetic, or endocannabinoids, exert their functions through activation of cannabinoid receptors, two of which have been well characterized to date: CB1 and CB2. Cannabinoids are neuroprotective against excitotoxicity and acute brain damage, both in vitro and in vivo. Several mechanisms account for the neuroprotection afforded by this type of drug such as blockade of excitotoxicity, reduction of calcium influx, antioxidant properties of the compounds, or enhanced trophic factor support. A decrease in proinflammatory mediators brought about by cannabinoids may be also involved in their neuroprotection… Cannabidiol (CBD), the major plant-derived nonpsychotropic constituent of marijuana, is of potential therapeutic interest in different disease conditions (e.g., inflammation)…

…this kind of drug with neuroprotective and anti-inflammatory effects may be of interest in the prevention of AD inflammation, in particular CB2-selective agonists, which are devoid of psychoactive effects…

Cannabidiol and other cannabinoids reduce microglial activation in vitro and in vivo…

CBD is able to modulate microglial cell function in vitro and induce beneficial effects in an in vivo model of AD.

Given that CBD lacks psychoactivity, it may represent a novel therapeutic approach for this neurological disease.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3102548/

Regulation of cannabinoid CB1 receptors in the central nervous system by chronic cannabinoids.

“The potential therapeutic benefits of certain cannabinoid-mediated effects, as well as the use of marijuana for its psychoactive properties, has raised interest in understanding the cellular adaptations produced by chronic administration of this class of drugs.”

http://www.ncbi.nlm.nih.gov/pubmed/14977366

Intact cannabinoid CB1 receptors in the Alzheimer’s disease cortex.

“The cannabinoid CB1 receptor has gained much attention as a potential pharmacotherapeutic target in various neurodegenerative diseases including Alzheimer’s disease (AD). Our study suggests that CB1 receptors are intact in AD and may play a role in preserving cognitive function.

 Therefore, CB1 receptors should be further assessed as a potential therapeutic target in AD.”

http://www.ncbi.nlm.nih.gov/pubmed/21034788

Molecular reorganization of endocannabinoid signalling in Alzheimer’s disease

“CB1 cannabinoid receptor expression is unchanged in Alzheimer’s disease

Therefore, endocannabinoid signalling networks may represent novel targets to reinstate the precision of synaptic communication under neurodegenerative conditions associated with cognitive deficit.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3069704/

Cannabinoid system in neurodegeneration: new perspectives in Alzheimer’s disease.

“Alzheimer’s disease is a chronic and progressive neurodegenerative disorder. The presence of functional cannabinoid CB2 receptors in central nervous system (CNS) has provoked that this receptor and its agonist ligands are now considered as promising pharmacological targets for neurological diseases. Herein, we review the evidences supporting the potential role of the ECS as a therapeutic target, focused on CB2 receptor and its ligands, for the treatment of Alzheimer’s disease.”

http://www.ncbi.nlm.nih.gov/pubmed/19456285

Cannabinoids and neurodegenerative diseases.

“Although significant advances have taken place in recent years on our understanding of the molecular mechanisms of different neurodegenerative diseases, its translation into effective therapeutic treatments has not been as successful as could be expected. There is still a dramatic lack of curative treatments for the most frequent disorders and only symptomatic relief for many others. Under this perspective, the search for novel therapeutic approaches is demanding and significant attention and efforts have been directed to studying additional neurotransmission systems including the endocannabinoid system (ECS).

The neuroprotective properties of exogenous as well as endogenous cannabinoids have been known for years and the underlying molecular mechanisms have been recently unveiled. As discussed later, antioxidative, antiglutamatergic and antiinflammatory effects are now recognized as derived from cannabinoid action and are known to be of common interest for many neurodegenerative processes.

 Thus, these characteristics make cannabinoids attractive candidates for the development of novel therapeutic strategies.

 The present review will focus on the existing data regarding the possible usefulness of cannabinoid agents for the treatment of relevant neurological pathologies for our society such as Alzheimer’s disease, multiple sclerosis, Huntington’s disease and amyotrophic lateral sclerosis.”

http://www.ncbi.nlm.nih.gov/pubmed/19839933

Cannabinoid CB1 receptor stimulation affords neuroprotection in MPTP-induced neurotoxicity by attenuating S100B up-regulation in vitro.

 “…the involvement of the endocannabinoid system was investigated by using selective inhibitors of endocannabinoid inactivation (cellular re-uptake or enzymatic hydrolysis) and selective cannabinoid CB1 and CB2 receptor antagonists and by silencing the CB1 receptor…

 Our data suggest that selective activation of CB1 receptors by either exogenous or endogenous cannabinoids might afford neuroprotection…”

http://www.ncbi.nlm.nih.gov/pubmed/17639288