[Essential fatty acids and lipid mediators. Endocannabinoids].

“Balance between omega-3 and omega-6 acids has a profound influence on all the body’s inflammatory responses and a raised level of PUFA omega-3 in tissue correlate with a reduced incidence of degenerative cardiovascular disease, some mental illnesses such as depression, and neuro-degenerative diseases such as Alzheimer’s.

Recent advances in the biochemistry and pharmacology of the endocannabinoid system…

will offer the development of novel therapeutic agents.”

http://www.ncbi.nlm.nih.gov/pubmed/22730630

Cannabinoid CB2 receptors and fatty acid amide hydrolase are selectively overexpressed in neuritic plaque-associated glia in Alzheimer’s disease brains.

.”We have studied the status of some of the components of the endocannabinoid system, fatty acid amide hydrolase and cannabinoid CB1 and CB2 receptors, in postmortem brains from patients with Alzheimer’s disease. Our results show that both fatty acid amide hydrolase and cannabinoid CB2 receptors are abundantly and selectively expressed in neuritic plaque-associated astrocytes and microglia, respectively, whereas the expression of CB1 receptors remains unchanged. In addition, the hydrolase activity seems to be elevated in the plaques and surrounding areas.

Thus, some elements of the endocannabinoid system may be postulated as possible modulators of the inflammatory response associated with this neurodegenerative process and as possible targets for new therapeutic approaches.

To our knowledge, this report is the first evidence for the presence of CB2 receptors in the human CNS. Furthermore, these receptors have recently been reported to play an important role in microglial migration. It is important to note that we detected CB2 receptors only in microglial cells, which is in agreement with the well known immunomodulatory effects of CB2 activation. Thus, many studies have shown that CB2 receptor activation leads to a myriad of changes in the production of inflammation-related substances, although with results that vary depending on the experimental model used and the concentration of cannabinoids used.

 In any case, the selective presence of CB2 receptors in microglial cells opens new perspectives on the role of CB2 receptors in the human CNS and suggests that the modulation of their activity may have therapeutic implications.”

http://www.jneurosci.org/content/23/35/11136.long

The development of cannabinoid CBII receptor agonists for the treatment of central neuropathies.

“Cannabinoids have been used in the treatment of nausea and emesis, anorexia and cachexia, tremor and pain associated with multiple sclerosis. These treatments are limited by the psychoactive side-effects of CBI activation. Recently CBII has been described within the CNS, both in microglia and neuronal progenitor cells (NPCs), but with few exceptions, not by neurons within the CNS.

This has suggested that CBII agonists could have potential to treat various conditions without psycho-activity.

This article reviews the potential for CBII agonists as treatments for neurological conditions, with a focus on microglia and NPCs as drug targets. We first discuss the role of microglia in the healthy brain, and then the role of microglia in chronic neuroinflammatory disorders, including Alzheimer’s disease and Parkinson’s disease, as well as in neuroinflammation following acute brain injury such as stroke and global hypoxia. As activation of CBII receptor on microglia results in suppression of the proliferation and activation of microglia, there is potential for the anti-inflammatory properties of CBII agonist to treat neuropathologies that involve heightened microglia activity. In addition, activating CBII receptors may result in an increase in proliferation and affect migration of NPCs.Therefore, it is possible that CBII agonists may assist in the treatment of neuropathologies by increasing neurogenesis…”

http://www.ncbi.nlm.nih.gov/pubmed/20236042

The activation of cannabinoid CB2 receptors stimulates in situ and in vitro beta-amyloid removal by human macrophages.

“The endocannabinoid system is a promising therapeutic target in a wide variety of diseases. However, the non-desirable psychotropic effects of natural and synthetic cannabinoids have largely counteracted their clinical usefulness. These effects are mostly mediated by cannabinoid receptors of the CB(1) type, that exhibit a wide distribution in neuronal elements of the CNS. Thus, the presence of other elements of this system in the CNS, such as CB(2) receptors, may open new possibilities for the development of cannabinoid-based therapies. These receptors are almost absent from the CNS in normal conditions but are up-regulated in glial cells under chronic neuroinflammatory stimuli, as has been described in Alzheimer’s disease. To understand the functional role of these receptors, we tested their role in the process of beta-amyloid removal, that is currently considered as one of the most promising experimental approaches for the treatment of this disease.

Our results show that a CB(2) agonist (JWH-015) is capable of inducing the removal of native beta-amyloid removal from human frozen tissue sections as well as of synthetic pathogenic peptide by a human macrophage cell line (THP-1). Remarkably, this effect was achieved at low doses and was specific for this type of cells, as U373MG astrocytoma cells did not respond to the treatment. The effect was CB(2)-mediated, at least partially, as the selective CB(2) antagonist SR144528 prevented the JWH-015-induced plaque removal in situ.

 These data corroborate the possible therapeutic interest of CB(2) cannabinoid specific chemicals in the treatment of Alzheimer’s disease.”

http://www.ncbi.nlm.nih.gov/pubmed/19505450

CB(2) receptor and amyloid pathology in frontal cortex of Alzheimer’s disease patients.

“The cannabinoid system seems to play an important role in various neurodegenerative diseases including Alzheimer’s disease (AD). The relationship of cannabinoid receptors (CB(1)R and CB(2)R) to cognitive function and neuropathological markers in AD remains unclear. In the present study, postmortem cortical brain tissues (Brodmann area 10) from a cohort of neuropathologically confirmed AD patients and age-matched controls were used to measure CB(1)R and CB(2)R by immunoblotting. Correlational analyses were performed for the neurochemical and cognitive data. CB(1)R expression was significantly decreased in AD. Levels of CB(1)R correlated with hypophagia, but not with any AD molecular marker or cognitive status (Mini Mental State Examination score). The level of CB(2)R was significantly higher (40%) in AD. Increases in the expression of the glial marker glial fibrillar acidic protein were also found. CB(2)R expression did not correlate with cognitive status. Interestingly, expression levels of CB(2)R correlated with two relevant AD molecular markers, Aβ(42) levels and senile plaque score.

These results may constitute the basis of CB(2)R-based therapies and/or diagnostic approaches.”

http://www.ncbi.nlm.nih.gov/pubmed/22763024

Cannabinoid CB2 receptors in human brain inflammation.

“CB2 receptors in neuroinflammatory conditions of the human brain.

“CB2 receptors have been found to be present in the CNS, thus offering new opportunities for the pharmacological use of cannabinoid agents. Furthermore, the fact that their expression is increased by inflammatory stimuli suggests that they may be involved in the pathogenesis and/or in the endogenous response to injury. Data obtained in vitro and in animal models show that CB2 receptors may be part of the general neuroprotective action of the ECS…

The anti-inflammatory effects triggered by the activation of the CB2 receptor make it an attractive target for the development of novel anti-inflammatory therapies.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2219537/

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/

Pot joins the fight against Alzheimer’s, memory loss

“The researchers ducked the obvious question of whether it might be simpler, faster and cheaper to simply light up a joint. “Could people smoke marijuana to prevent Alzheimer’s disease if the disease is in their family?” Wenk said in a statement. “We’re not saying that, but it might actually work.””

http://www.scientificamerican.com/blog/post.cfm?id=pot-joins-the-fight-against-alzheim-2008-11-19

Cannabidiol in vivo blunts beta-amyloid induced neuroinflammation by suppressing IL-1beta and iNOS expression.

“Pharmacological inhibition of beta-amyloid (Aβ) induced reactive gliosis may represent a novel rationale to develop drugs able to blunt neuronal damage and slow the course of Alzheimer’s disease (AD). Cannabidiol (CBD), the main non-psychotropic natural cannabinoid, exerts in vitro a combination of neuroprotective effects in different models of Aβ neurotoxicity. The present study, performed in a mouse model of AD-related neuroinflammation, was aimed at confirming in vivo the previously reported antiinflammatory properties of CBD.

Cannabidiol (CBD), the main non-psychotropic component of the glandular hairs of Cannabis sativa, exhibits a plethora of actions including anti-convulsive, sedative, hypnotic, anti-psychotic, anti-nausea, anti-inflammatory and anti-hyperalgesic properties. CBD has been proved to exert in vitro a combination of neuroprotective effects in Aβ-induced neurotoxicity, including anti-oxidant and anti-apoptotic effects, tau protein hyperphosphorylation inhibition through the Wnt pathway, and marked decrease of inducible nitric oxide synthase (iNOS) protein expression and nitrite production in Aβ-challenged differentiated rat neuronal cells.

In spite of the large amount of data describing the significant neuroprotective and anti-inflammatory properties of CBD in vitro, to date no evidence has been provided showing similar effects in vivo. To achieve this, the present study investigated the potential anti-inflammatory effect of CBD in a mouse model of AD-related neuroinflammation induced by the intrahippocampal injection of the human Aβ (1–42) fragment.

The results of the present study confirm in vivo anti-inflammatory actions of CBD, emphasizing the importance of this compound as a novel promising pharmacological tool capable of attenuating Aβ evoked neuroinflammatory responses.

 …on the basis of the present results, CBD, a drug well tolerated in humans, may be regarded as an attractive medical alternative for the treatment of AD, because of its lack of psychoactive and cognitive effects.”

Read more: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2189818/