Israeli Research Shows Cannabidiol May Slow Alzheimer’s Disease

“An Israeli researcher has found that a non-psychoactive component of cannabis may help slow the progression of Alzheimer’s disease. The initial findings of a study at the Hebrew University of Jerusalem show that a non-psychoactive component of cannabis, marijuana, may hold out hope for slowing down the progression of Alzheimer’s disease.The research, still at an early stage, indicates that memory loss, the first and primary symptom of Alzheimer’s disease, can be slowed down significantly in mice by cannabidiol. Alzheimer’s disease, the most common form of dementia, affects some 24.3 million people worldwide.”

Read more: http://www.israelnationalnews.com/News/News.aspx/125564

Cannabidiol Reduces Aβ-Induced Neuroinflammation and Promotes Hippocampal Neurogenesis through PPARγ Involvement

“CBD blunted neuroinflammation sustained by astrocytes through PPARγ selective activation in vitro and in vivo.

Results from the present study prove the selective involvement of PPARγ in the anti-inflammatory and neuroprotective effects of CBD here observed either in vitro and in vivo. In addition, CBD significantly promoted neurogenesis in Aβ injured rat hippocampi, much expanding its already wide spectrum of beneficial actions exerted in AD models, a non negligible effect, due to its capability to activate PPARγ.

In conclusion, results of the present research demonstrate that CBD may exert protective functions through a PPARγ dependent activation, which leads to a reduction in reactive gliosis and consequently in neurodegeneration. Moreover, in the current experimental conditions this phytocannabinoid appears to stimulate neurogenesis since it increases DCX immunopositive cell proliferation rate in rat DG.

Innovative therapeutic approaches which could significantly improve AD course require new molecules that will be able to have an impact on different pathological pathways, which converge at the progressive neurological decline. CBD has shown a capability to profoundly reduce reactive astrogliosis and to guarantee both direct and indirect neuronal protection in Aβ induced neuroinflammation/neurodegeration. So far, the lack of understanding of the precise molecular mechanism involved in CBD pharmacological actions, has had limited interest and has puzzled investigators.

Currently, findings of the present study throw some light on the issue, and frame CBD as a new PPARγ activator.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3230631/

[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

Activation of the CB(2) receptor system reverses amyloid-induced memory deficiency.

“Cannabinoid type 2 (CB(2)) agonists are neuroprotective and appear to play modulatory roles in neurodegenerative processes in Alzheimer’s disease. We have studied the effect of 1-((3-benzyl-3-methyl-2,3-dihydro-1-benzofuran-6-yl) carbonyl) piperidine (MDA7)-a novel selective CB(2) agonist that lacks psychoactivity-on ameliorating the neuroinflammatory process, synaptic dysfunction, and cognitive impairment 

 Our findings suggest that MDA7 is an innovative therapeutic approach for the treatment of Alzheimer’s disease.”

http://www.ncbi.nlm.nih.gov/pubmed/22795792

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

A molecular link between the active component of marijuana and Alzheimer’s disease pathology.

“A link between the endocannabinoid system and Alzheimer’s disease has been discovered which has provided a new therapeutic target for the treatment of patients suffering from Alzheimer’s disease. These studies have demonstrated the ability of cannabinoids to provide neuroprotection against β-amyloid peptide (Aβ) toxicity.

Here, we demonstrate that the active component of marijuana, Δ9-tetrahydrocannabinol (THC), competitively inhibits the enzyme acetylcholinesterase (AChE) as well as prevents AChE-induced amyloid β-peptide (Aβ) aggregation, the key pathological marker of Alzheimer’s disease. 

 Compared to currently approved drugs prescribed for the treatment of Alzheimer’s disease, THC is a considerably superior inhibitor of Aβ aggregation, and this study provides a previously unrecognized molecular mechanism through which cannabinoid molecules may directly impact the progression of this debilitating disease.

Since the characterization of the Cannabis sativa-produced cannabinoid, Δ9-tetrahydrocannabinol (THC), in the 1960’s,1 this natural product has been widely explored as an anti-emetic, anti-convulsive, anti-inflammatory, and analgesic.”

Read more: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2562334/

 

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

The role of phytochemicals in the treatment and prevention of dementia.

Drugs & Aging

“Dementia pathologies such as Alzheimer’s disease (AD) are reaching epidemic proportions, yet they are not successfully managed by effective symptomatic treatments. Only five drugs have been developed to alleviate cognitive symptoms, and more effective and safe treatments are needed for both the cognitive symptoms and behavioural and psychological symptoms of dementia (BPSD). As two of these licensed drugs (cholinesterase inhibitors [ChEIs]) are naturally derived (galantamine and rivastigmine), the potential for plants to yield new therapeutic agents has stimulated extensive research to discover new ChEIs together with plant extracts, phytochemicals and their derivatives with other mechanistic effects relevant to dementia treatment. This review presents the potential and actual therapeutic strategies for dementia in relation to the known mechanisms of dementia pathology. Phytochemicals that have shown mechanistic effects relevant to the pathological targets in dementia are discussed, with an emphasis on those showing positive clinical trial evidence. Those phytochemicals discussed include the alkaloid physostigmine, a ChEI from the calabar bean (Physostigma venenosum), which has been used as a template for the development of synthetic derivatives that inhibit acetylcholinesterase, including the drug rivastigmine. Also discussed are other ChEI alkaloids including huperzine A, from Huperzia serrata, and galantamine, originally from the snowdrop (Galanthus woronowii); both alkaloids improve cognitive functions in AD patients.

Other phytochemicals discussed include cannabinoids (e.g. cannabidiol) from Cannabis sativa, which are emerging as potential therapeutic agents for BPSD, and resveratrol (occurs in various plants) and curcumin (from turmeric [Curcuma longa]), which have been investigated for their pharmacological activities relevant to dementia and their potential effects on delaying dementia progression. The review also discusses plant extracts, and their known constituents, that have shown relevant mechanistic effects for dementia and promising clinical data, but require more evidence for their clinical efficacy and safety. Such plants include Ginkgo biloba, which has been extensively studied in numerous clinical trials, with most outcomes showing positive effects on cognitive functions in dementia patients; however, more reliable and consistent clinical data are needed to confirm efficacy. Other plants and their extracts that have produced promising clinical data in dementia patients, with respect to cognition, include saffron (Crocus sativus), ginseng (Panax species), sage (Salvia species) and lemon balm (Melissa officinalis), although more extensive and reliable clinical data are required. Other plants that are used in traditional practices of medicine have been suggested to improve cognitive functions (e.g. Polygala tenuifolia) or have been associated with alleviation of BPSD (e.g. the traditional prescription yokukansan); such remedies are often prescribed as complex mixtures of different plants, which complicates interpretation of pharmacological and clinical data and introduces additional challenges for quality control. Evidence for the role of natural products in disease prevention, the primary but considerably challenging aim with respect to dementia, is limited, but the available epidemiological and clinical evidence is discussed, with most studies focused on ChEIs, nicotine (from Nicotiana species), curcumin, wine polyphenols such as resveratrol and G. biloba. Challenges for the development of phytochemicals as drugs and for quality control of standardized plant extracts are also considered.”

http://www.ncbi.nlm.nih.gov/pubmed/21639405

https://link.springer.com/article/10.2165%2F11591310-000000000-00000