Crosstalk between the M1 muscarinic acetylcholine receptor and the endocannabinoid system: A relevance for Alzheimer’s disease?

Posted on January 25, 2020 by David

Cellular Signalling “Alzheimer’s disease (AD) is a neurodegenerative disorder which accounts for 60-70% of the 50 million worldwide cases of dementia and is characterised by cognitive impairments, many of which have long been associated with dysfunction of the cholinergic system.

Although the M₁ muscarinic acetylcholine receptor (mAChR) is considered a promising drug target for AD, ligands targeting this receptor have so far been unsuccessful in clinical trials.

As modulatory receptors to cholinergic transmission, the endocannabinoid system may be a promising drug target to allow fine tuning of the cholinergic system. Furthermore, disease-related changes have been found in the endocannabinoid system during AD progression and indeed targeting the endocannabinoid system at specific disease stages alleviates cognitive symptoms in numerous mouse models of AD.

Here we review the role of the endocannabinoid system in AD, and its crosstalk with mAChRs as a potential drug target for cholinergic dysfunction.”

https://www.ncbi.nlm.nih.gov/pubmed/31978506

“Targeting the endocannabinoid system could fine tune the cholinergic system”

https://www.sciencedirect.com/science/article/abs/pii/S089865682030022X?via%3Dihub

A Review on Studies of Marijuana for Alzheimer’s Disease – Focusing on CBD, THC.

Posted on January 25, 2020 by David

book “This study was to discuss the research trend of dementia treatment using cannabis for the purpose of providing the basis of cannabis use for medical purposes in the future.

RESULTS:

These results implied that the CBD components of cannabis might be useful to treat and prevent AD because CBD components could suppress the main causal factors of AD.

Moreover, it was suggested that using CBD and THC together could be more useful than using CBD or THC alone.

CONCLUSION:

We hope that there will be a solid foundation to use cannabis for medical use by continuously evaluating the possibility of using cannabis for clinical purposes as a dementia treatment substance and cannabis can be used as a positive tool.”

https://www.ncbi.nlm.nih.gov/pubmed/31970019

“The ideal treatment for Alzheimer’s disease (AD) should be able to modulate the disease through multiple mechanisms rather than targeting a single dysregulated pathway.” http://www.ncbi.nlm.nih.gov/pubmed/25147120

“THC could be a potential therapeutic treatment option for Alzheimer’s disease through multiple functions and pathways.” http://www.ncbi.nlm.nih.gov/pubmed/25024327

“CBD treatment would be in line with preventative, multimodal drug strategies targeting a combination of pathological symptoms, which might be ideal for AD #therapy.” http://www.ncbi.nlm.nih.gov/pubmed/27471947

“Combination of THC and CBD exhibits a better therapeutic profile than each cannabis component alone and support the consideration of a cannabis-based medicine as potential therapy against AD.” http://www.ncbi.nlm.nih.gov/pubmed/25125475

http://www.thctotalhealthcare.com/category/alzheimers-disease-ad/

Targeting Cannabinoid Receptor Activation and BACE-1 Activity Counteracts TgAPP Mice Memory Impairment and Alzheimer’s Disease Lymphoblast Alterations.

Posted on January 8, 2020 by David

“Alzheimer’s disease (AD), the leading cause of dementia in the elderly, is a neurodegenerative disorder marked by progressive impairment of cognitive ability. Patients with AD display neuropathological lesions including senile plaques, neurofibrillary tangles, and neuronal loss.

There are no disease-modifying drugs currently available. With the number of affected individuals increasing dramatically throughout the world, there is obvious urgent need for effective treatment strategy for AD.

The multifactorial nature of AD encouraged the development of multifunctional compounds, able to interact with several putative targets. Here, we have evaluated the effects of two in-house designed cannabinoid receptors (CB) agonists showing inhibitory actions on β-secretase-1 (BACE-1) (NP137) and BACE-1/butyrylcholinesterase (BuChE) (NP148), on cellular models of AD, including immortalized lymphocytes from late-onset AD patients.

We report here that NP137 and NP148 showed neuroprotective effects in amyloid-β-treated primary cortical neurons, and NP137 in particular rescued the cognitive deficit of TgAPP mice. The latter compound was able to blunt the abnormal cell response to serum addition or withdrawal of lymphoblasts derived from AD patients.

It is suggested that NP137 could be a good drug candidate for future treatment of AD.”

https://www.ncbi.nlm.nih.gov/pubmed/31898159

https://link.springer.com/article/10.1007%2Fs12035-019-01813-4

“The ideal treatment for AD should be able to modulate the disease through multiple mechanisms rather than targeting a single dysregulated pathway.” http://www.ncbi.nlm.nih.gov/pubmed/25147120

“These sets of data strongly suggest that THC could be a potential therapeutic treatment option for Alzheimer’s disease through multiple functions and pathways.” http://www.ncbi.nlm.nih.gov/pubmed/25024327

“In fact, exogenous and endogenous cannabinoids seem to be able to modulate multiple processes in AD” http://www.ncbi.nlm.nih.gov/pubmed/25147120

“Our results indicate that cannabinoid receptors are important in the pathology of AD and that cannabinoids succeed in preventing the neurodegenerative process occurring in the disease.” http://www.ncbi.nlm.nih.gov/pubmed/15728830

“Based on the complex pathology of AD, a preventative, multimodal drug approach targeting a combination of pathological AD symptoms appears ideal. Importantly, cannabinoids show anti-inflammatory, neuroprotective and antioxidant properties and have immunosuppressive effects.” http://www.ncbi.nlm.nih.gov/pubmed/22448595

“CBD treatment would be in line with preventative, multimodal drug strategies targeting a combination of pathological symptoms, which might be ideal for AD therapy.” http://www.ncbi.nlm.nih.gov/pubmed/27471947

Cannabinoids for the Neuropsychiatric Symptoms of Dementia: A Systematic Review and Meta-Analysis.

Posted on December 15, 2019 by David

AIM:

To assess the efficacy and acceptability of cannabinoids for the treatment of NPS in individuals with dementia.

FINDINGS:

Cannabinoids led to significant improvements across NPS instruments, including the Cohen Mansfield Agitation Inventory (SMD = -0.80; 95% confidence interval [CI], -1.45 to -0.16), the Neuropsychiatric Inventory (SMD = -0.61; CI, -1.07 to -0.15), and nocturnal actigraphy (SMD = -1.05; CI, -1.56 to -0.54h). Cannabinoids were well-tolerated, with an overall trial completion rate of 93% (193/205) and no serious treatment-related adverse events. Treatment efficacy was associated with baseline dementia severity and dose, but not dementia subtype, age, or sex. The overall study quality was rated as low.

CONCLUSIONS:

There is preliminary evidence for the efficacy and tolerability of cannabinoids as treatments for NPS. Population-based studies are needed to characterize their real-world effectiveness and acceptability.”

https://www.ncbi.nlm.nih.gov/pubmed/31835954

https://journals.sagepub.com/doi/abs/10.1177/0706743719892717?journalCode=cpab

Cannabinoids and the expanded endocannabinoid system in neurological disorders.

Posted on December 14, 2019 by David

Related image “Anecdotal evidence that cannabis preparations have medical benefits together with the discovery of the psychotropic plant cannabinoid Δ⁹-tetrahydrocannabinol (THC) initiated efforts to develop cannabinoid-based therapeutics.

These efforts have been marked by disappointment, especially in relation to the unwanted central effects that result from activation of cannabinoid receptor 1 (CB1), which have limited the therapeutic use of drugs that activate or inactivate this receptor.

The discovery of CB2 and of endogenous cannabinoid receptor ligands (endocannabinoids) raised new possibilities for safe targeting of this endocannabinoid system. However, clinical success has been limited, complicated by the discovery of an expanded endocannabinoid system – known as the endocannabinoidome – that includes several mediators that are biochemically related to the endocannabinoids, and their receptors and metabolic enzymes.

The approvals of nabiximols, a mixture of THC and the non-psychotropic cannabinoid cannabidiol, for the treatment of spasticity and neuropathic pain in multiple sclerosis, and of purified botanical cannabidiol for the treatment of otherwise untreatable forms of paediatric epilepsy, have brought the therapeutic use of cannabinoids and endocannabinoids in neurological diseases into the limelight.

In this Review, we provide an overview of the endocannabinoid system and the endocannabinoidome before discussing their involvement in and clinical relevance to a variety of neurological disorders, including Parkinson disease, Alzheimer disease, Huntington disease, multiple sclerosis, amyotrophic lateral sclerosis, traumatic brain injury, stroke, epilepsy and glioblastoma.”

https://www.ncbi.nlm.nih.gov/pubmed/31831863

“The existence of the endocannabinoidome explains in part why some non-euphoric cannabinoids, which affect several endocannabinoidome proteins, are useful for the treatment of neurological disorders, such as multiple sclerosis and epilepsy.”

https://www.nature.com/articles/s41582-019-0284-z

The Cannabinoid Receptor Agonist WIN55,212-2 Ameliorates Hippocampal Neuronal Damage After Chronic Cerebral Hypoperfusion Possibly Through Inhibiting Oxidative Stress and ASK1-p38 Signaling.

Posted on December 8, 2019 by David

“Chronic cerebral hypoperfusion (CCH) is a major contributor to cognitive decline and degenerative processes leading to Alzheimer’s disease, vascular dementia, and aging. However, the delicate mechanism of CCH-induced neuronal damage, and therefore proper treatment, remains unclear.

WIN55,212-2 (WIN) is a nonselective cannabinoid receptor agonist that has been shown to have effects on hippocampal neuron survival. In this study, we investigated the potential roles of WIN, as well as its underlying mechanism in a rat CCH model of bilateral common carotid artery occlusion.

These findings indicated that WIN may be a potential therapeutic agent for ischemic neuronal damage, involving a mechanism associated with the suppression of oxidative stress and ASK1-p38 signaling.”

https://www.ncbi.nlm.nih.gov/pubmed/31808139

https://link.springer.com/article/10.1007%2Fs12640-019-00141-8

Kinetics of acetylcholinesterase inhibition by hemp seed protein-derived peptides.

Posted on October 21, 2019 by David

Journal of Food Biochemistry banner “The aim of this work was to enhance the acetylcholinesterase (AChE)-inhibitory activity of a pepsin-produced hemp seed protein hydrolysates (HPH) through reverse-phase HPLC separation followed by identification of peptide sequences present in the most active fraction. The HPH was separated into eight fractions (F1-F8) with F7 exhibiting significantly (p < 0.05) the strongest (97.5%) in vitro inhibition of electric eel AChE (eeAChE) activity in comparison to 53.8% for HPH. The HPH consisted mostly of low molecular weight peptides of < 11 amino acid residues and most contained at least one hydrophobic amino acid. Kinetics of enzyme inhibition revealed a mixed-type inhibition of eeAChE activity by HPH whereas F7 acted through an uncompetitive mode; in contrast inhibition of human AChE by HPH and F7 was uncompetitive. The stronger inhibitory potency of the F7 peptides fraction against both enzymes was confirmed through reduced maximal velocity, catalytic efficiency, and inhibition constant values when compared to the HPH.

PRACTICAL APPLICATIONS: The use of natural products for the prevention or treatment of human diseases continues to be an area of intense research activities. Food protein-derived peptides obtained through enzymatic hydrolysis of hemp seed proteins were shown in vitro to be strong inhibitors of activities of both the eel and human forms of acetylcholinesterase (AChE). AChE is an important therapeutic target because excessive activity of this enzyme is a causative factor of neurodegenerative diseases such as dementia and Alzheimer’s. This work showed that peptides in the most active fraction are small in sizes, which may favor their absorption into blood circulation and possible permeation of the blood-brain barrier. Therefore, the hemp seed peptides are potential agents that can be used to formulate functional foods and nutraceuticals against neurodegenerative diseases.”

https://www.ncbi.nlm.nih.gov/pubmed/31353736

https://onlinelibrary.wiley.com/doi/abs/10.1111/jfbc.12897

Agitation, Oxidative Stress, and Cytokines in Alzheimer Disease: Biomarker Analyses From a Clinical Trial With Nabilone for Agitation.

Posted on September 25, 2019 by David

“The endocannabinoid system has been a target of interest for agitation in Alzheimer disease (AD) because of potential behavioral effects and its potential impact on mechanisms implicated in AD such as oxidative stress (OS) and neuroinflammation.

We explored whether serum markers of OS and neuroinflammation were associated with response to the cannabinoid nabilone in agitated patients with AD (N = 38).

These findings suggest that OS and neuroinflammation may be associated with agitation severity, while nabilone may have anti-inflammatory effects.”

https://www.ncbi.nlm.nih.gov/pubmed/31547752

https://journals.sagepub.com/doi/abs/10.1177/0891988719874118?journalCode=jgpb

Novel cannabis flavonoid, cannflavin A displays both a hormetic and neuroprotective profile against amyloid β-mediated neurotoxicity in PC12 cells: comparison with geranylated flavonoids, mimulone and diplacone.

Posted on August 23, 2019 by David

Biochemical Pharmacology

“Flavonoids form a diverse class of naturally occurring polyphenols ascribed various biological activities, including inhibition of amyloid β (Aβ) fibrillisation and neurotoxicity of relevance to Alzheimer’s disease.

Cannabis contains a unique subset of prenylated flavonoids, the cannflavins.

While selected conventional flavonoids have demonstrated anti-amyloid and neuroprotective potential, any neuroprotective bioactivity of prenylated flavonoids has not been determined.

We evaluated the in vitro neuroprotective and anti-aggregative properties of the novel geranylated cannabis-derived flavonoid, cannflavin A against Aβ_1-42 and compared it to two similarly geranylated flavonoids, mimulone and diplacone, to compare the bioactive properties of these unique flavonoids more broadly.

RESULTS:

Cannflavin A demonstrated intrinsic hormetic effects on cell viability, increasing viability by 40% from 1-10µM but displaying neurotoxicity at higher (>10-100µM) concentrations. Neither mimulone nor diplacone exhibited such a biphasic effect, instead showing only concentration-dependent neurotoxicity, with diplacone the more potent (from >1 µM). However at the lower concentrations (<10µM), cannflavin A increased cell viability by up to 40%, while 10µM cannflavin A inhibited the neurotoxicity elicited by Aβ_1-42 (0-2µM), reducing Aβ aggregate adherence to PC-12 cells and associated neurite loss. The neuroprotective effects of cannflavin A were associated with a direct inhibition of Aβ_1-42 fibril and aggregate density, evidenced by attenuated ThT fluorescence kinetics and microscopic evidence of both altered and diminished density of Aβ aggregate and fibril morphology via electron microscopy.

CONCLUSIONS:

These findings highlight a concentration-dependent hormetic and neuroprotective role of cannflavin A against Aβ-mediated neurotoxicity, associated with an inhibition of Aβ fibrillisation. The efficacy of the cannabis flavone may itself direct further lead development targeting neurodegeneration in Alzheimer’s disease. However, the geranylated flavonoids generally displayed a comparatively potent neurotoxicity not observed with many conventional flavonoids in vitro.”

https://www.ncbi.nlm.nih.gov/pubmed/31437460

https://www.sciencedirect.com/science/article/abs/pii/S0006295219302990?via%3Dihub

The Acute Activation of the CB1 Receptor in the Hippocampus Decreases Neurotoxicity and Prevents Spatial Memory Impairment in Rats Lesioned with β-Amyloid 25-35.

Posted on August 11, 2019 by David

Neuroscience “Given their anti-inflammatory properties, cannabinoids have been shown to be neuroprotective agents and to reduce excitotoxicity, through the activation of the Cannabinoid receptor type 1 (CB1r).

These properties have led to CB1r being proposed as pharmacological targets for the treatment of various neurodegenerative diseases.

This study aimed to evaluate the neuroprotective effect of an acute activation of CB1r on spatial memory and its impact on iNOS protein expression, NO● levels, gliosis and the neurodegenerative process induced by the injection of Aβ_(25-35) into the CA1 subfield of the hippocampus.

The data obtained in the present research suggest that the acute early activation of CB1r is crucial for neuroprotection.”

https://www.ncbi.nlm.nih.gov/pubmed/31400487

https://www.sciencedirect.com/science/article/abs/pii/S0306452219305433?via%3Dihub