Cannabidiol inhibits sucrose self-administration by CB1 and CB2 receptor mechanisms in rodents.

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“A growing number of studies suggest therapeutic applications of cannabidiol (CBD), a recently U.S. Food and Drug Administration (FDA)-approved medication for epilepsy, in treatment of many other neuropsychological disorders. However, pharmacological action and the mechanisms by which CBD exerts its effects are not fully understood.

Here, we examined the effects of CBD on oral sucrose self-administration in rodents and explored the receptor mechanisms underlying CBD-induced behavioral effects using pharmacological and transgenic approaches.

Systemic administration of CBD produced a dose-dependent reduction in sucrose self-administration in rats and in wild-type (WT) and CB1-/- mice but not in CB2-/- mice. CBD appeared to be more efficacious in CB1-/- mice than in WT mice.

Similarly, pretreatment with AM251, a CB1R antagonist, potentiated, while AM630, a selective CB2R antagonist, blocked CBD-induced reduction in sucrose self-administration, suggesting the involvement of CB1 and CB2 receptors.

Taken together, the present findings suggest that CBD may have therapeutic potential in reducing binge eating and the development of obesity.”

https://www.ncbi.nlm.nih.gov/pubmed/31215752

https://onlinelibrary.wiley.com/doi/abs/10.1111/adb.12783

Safety and effectiveness of cannabinoids for the treatment of neuropsychiatric symptoms in dementia: a systematic review.

SAGE Journals“Neuropsychiatric symptoms (NPS) in dementia impact profoundly on the quality of life of people living with dementia and their care givers. Evidence for the effectiveness and safety of current therapeutic options is varied.

Cannabinoids have been proposed as an alternative therapy, mainly due to their activity on CB1 receptors in the central nervous system. However, little is known regarding the safety and effectiveness of cannabinoid therapy in people with dementia.

A literature review was undertaken to identify, describe and critically appraise studies investigating cannabinoid use in treating NPS in dementia.

RESULTS:

Twelve studies met the inclusion criteria. There was considerable variability across the studies with respect to study design (50% randomized controlled trials), intervention [dronabinol (33%), nabilone (25%) or delta-9 tetrahydrocannabinol (THC; 42%)] and outcome measures.

Dronabinol (three studies) and THC (one study) were associated with significant improvements in a range of neuropsychiatric scores.

The most common adverse drug event (ADE) reported was sedation. A high risk of bias was found in eight studies. The highest-quality trial found no significant improvement in symptoms or difference in ADE rate between treatment arms. Included studies used low doses of oral cannabinoids and this may have contributed to the lack of demonstrated efficacy.

CONCLUSION:

While the efficacy of cannabinoids was not proven in a robust randomized control trial, observational studies showed promising results, especially for patients whose symptoms were refractory. In addition, the safety profile is favourable as most of the ADEs reported were mild. Future trials may want to consider dose escalation and formulations with improved bioavailability.”

https://www.ncbi.nlm.nih.gov/pubmed/31205674

https://journals.sagepub.com/doi/10.1177/2042098619846993

Effect of cannabidiol on endocannabinoid, glutamatergic and GABAergic signalling markers in male offspring of a maternal immune activation (poly I:C) model relevant to schizophrenia.

Progress in Neuro-Psychopharmacology and Biological Psychiatry

“The mainstay treatment for schizophrenia is antipsychotic drugs (APDs), which are mostly effective against the positive symptoms (e.g. hallucinations), but provide minimal benefits for the negative symptoms (e.g. social withdrawal) and cognitive deficits.

We have recently shown that treatment with the non-intoxicating phytocannabinoid, cannabidiol (CBD), can improve cognition and social interaction deficits in a maternal immune activation (MIA) model relevant to the aetiology of schizophrenia, however, the mechanisms underlying this effect are unknown.

An imbalance in the main excitatory (glutamate) and inhibitory (GABA) neurotransmitter systems in the brain plays a role in the pathophysiology of schizophrenia. Therefore, the endocannabinoid system could represent a therapeutic target for schizophrenia as a regulator of glutamate and GABA release via the CB1 receptor (CB1R).

Overall, these findings show that CBD can restore cannabinoid/GABAergic signalling deficits in regions of the brain implicated in schizophrenia pathophysiology following maternal poly I:C exposure. These findings provide novel evidence for the potential mechanisms underlying the therapeutic effects of CBD treatment in the poly I:C model.”

https://www.ncbi.nlm.nih.gov/pubmed/31202911

https://www.sciencedirect.com/science/article/pii/S027858461930106X?via%3Dihub

Endogenous and synthetic cannabinoids induce the downregulation of cannabinoid CB1 receptor in retina.

Experimental Eye Research

“Endogenous and synthetic cannabinoids have been shown to provide neuroprotection to retinal neurons in acute animal models of retinopathy.

Chronic exposure to cannabinoid receptor (CB1R) agonists has been reported to induce downregulation of the CB1R in brain and behavioral tolerance.

The aim of this study was to investigate the effect of subchronic/chronic cannabinoid administration on CB1R downregulation in normal rat retina, its downstream prosurvival signaling and subsequent effect on retinal neuroprotection against AMPA excitotoxicity.

This study provides novel information regarding agonist-induced CB1R downregulation in rat retina after subchronic/chronic cannabinoid treatment, and its effect on downstream prosurvival signaling and neuroprotection.”

https://www.ncbi.nlm.nih.gov/pubmed/31199905

https://www.sciencedirect.com/science/article/pii/S0014483519301216?via%3Dihub

Selective modulation of the cannabinoid type 1 (CB1) receptor as an emerging platform for the treatment of neuropathic pain.

“Neuropathic pain is caused by a lesion or dysfunction in the nervous system, and it may arise from illness, be drug-induced or caused by toxin exposure. Since the discovery of two G-protein-coupled cannabinoid receptors (CB1 and CB2) nearly three decades ago, there has been a rapid expansion in our understanding of cannabinoid pharmacology. This is currently one of the most active fields of neuropharmacology, and interest has emerged in developing cannabinoids and other small molecule modulators of CB1 and CB2 as therapeutics for neuropathic pain. This short review article provides an overview of the chemotypes currently under investigation for the development of novel neuropathic pain treatments targeting CB1 receptors.”

Graphical abstract: Selective modulation of the cannabinoid type 1 (CB1) receptor as an emerging platform for the treatment of neuropathic pain

Novel CB1-ligands maintain homeostasis of the endocannabinoid-system in ω3- and ω6-long chain-PUFA deficiency.

The Journal of Lipid Research“Mammalian ω3- and ω6-PUFAs are synthesized from essential fatty acids (EFAs) or supplied by the diet. PUFAs are constitutive elements of membrane-architecture and precursors of lipid signaling molecules. EFAs and long chain PUFAs are precursors in the synthesis of endocannabinoid-ligands of the Gi/o-protein coupled cannabinoid receptors 1 and 2 in the endocannabinoid-system, which critically regulates energy homeostasis, as metabolic signaling system in hypothalamic neuronal circuits, and behavioral parameters. We utilized the auxotrophic fatty acid desaturase 2 deficient (fads2-/-) mouse, deficient in long chain PUFA-synthesis, to follow the age dependent dynamics of the PUFA pattern in the CNS-phospholipidome in unbiased dietary studies of three cohorts on sustained long chain PUFA-free, ω6-arachidonic and ω3-docosahexaenoic acid supplemented diets and their impact on the precursor pool of CB1 ligands. We discovered the transformation of eicosa-all cis-5,11,14-trienoic acid, uncommon in mammalian lipidomes, into two novel endocannabinoids, 20:35,11,14-ethanolamide and 2-20:35,11,14-glycerol, acting as ligands of CB1 in HEK293-cells. Labeling experiments excluded a Δ8-desaturase activity and proved the position-specificity of FADS2. The fads2 -/- mutant might serve as an unbiased model in vivo in the development of novel CB1-agonists and antagonists.”

https://www.ncbi.nlm.nih.gov/pubmed/31167809

http://www.jlr.org/content/early/2019/06/05/jlr.M094664

Countering the Modern Metabolic Disease Rampage With Ancestral Endocannabinoid System Alignment.

 Image result for frontiers in endocrinology

“When primitive vertebrates evolved from ancestral members of the animal kingdom and acquired complex locomotive and neurological toolsets, a constant supply of energy became necessary for their continued survival. To help fulfill this need, the endocannabinoid (eCB) system transformed drastically with the addition of the cannabinoid-1 receptor (CB1R) to its gene repertoire. This established an eCB/CB1R signaling mechanism responsible for governing the whole organism’s energy balance, with its activation triggering a shift toward energy intake and storage in the brain and the peripheral organs (i.e., liver and adipose).

Although this function was of primal importance for humans during their pre-historic existence as hunter-gatherers, it became expendable following the successive lifestyle shifts of the Agricultural and Industrial Revolutions. Modernization of the world has further increased food availability and decreased energy expenditure, thus shifting the eCB/CB1R system into a state of hyperactive deregulated signaling that contributes to the 21st century metabolic disease pandemic.

Studies from the literature supporting this perspective come from a variety of disciplines, including biochemistry, human medicine, evolutionary/comparative biology, anthropology, and developmental biology. Consideration of both biological and cultural evolution justifies the design of improved pharmacological treatments for obesity and Type 2 diabetes (T2D) that focus on peripheral CB1R antagonism. Blockade of peripheral CB1Rs, which universally promote energy conservation across the vertebrate lineage, represents an evolutionary medicine strategy for clinical management of present-day metabolic disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/31156558

https://www.frontiersin.org/articles/10.3389/fendo.2019.00311/full

Cannabinoid Receptor 1 Blockade Attenuates Obesity and Adipose Tissue Type 1 Inflammation Through miR-30e-5p Regulation of Delta-Like-4 in Macrophages and Consequently Downregulation of Th1 Cells.

 Image result for frontier in immunology“Obesity is characterized by chronic low-grade inflammation that contributes to development of cardiometabolic disorders. Cannabinoid receptor 1 (CB1) antagonists attenuate diet-induced obesity (DIO) and related inflammation, although the precise anti-inflammatory mechanisms involved have not been fully explored. In the current study we used a mouse model of DIO intervention to determine the microRNA (miRNA, miR)-mediated anti-obesity and anti-inflammatory effects of the CB1 antagonist, AM251. DIO mice that were fed high-fat diet (HFD) for 12 weeks were treated with AM251 (10 mg/kg) for an additional 4 weeks. HFD + AM251 mice experienced rapid and prolonged weight loss and reduced inflammatory M1 adipose tissue macrophage (ATM) infiltration. To investigate miRNA-mediated regulation of ATMs, F4/80+ cells from stromal vascular fractions (SVF) of epididymal fat were subjected to miR microarray analysis. Several miRs were differentially expressed in AM251-treated mice that were independent of calorie restriction. Prominently, miR-30e-5p was upregulated in ATMs from HFD + AM251 mice while the miR-30e-5p target, DLL4, was downregulated. Consistent with a decrease in DLL4-Notch signaling, fat storage and pro-inflammatory cytokine/chemokine expression was reduced following AM251 treatment. Furthermore, we found that AM251-treated macrophages can suppress DLL4-mediated Th1 polarization in CD4+ T cells. Together these data demonstrate that blocking CB1 receptors leads to upregulation of miR-30e-5p and down regulation of DLL4 in ATMs, which in turn suppress DLL4-Notch signaling-induced polarization of inflammatory Th1 cells and adipocyte energy storage. This combined effect of ATMs and T cells leads to an anti-inflammatory state and attenuation of DIO. These data support therapeutic potential of miR-30 in the treatment of cardiometabolic disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/31134094

https://www.frontiersin.org/articles/10.3389/fimmu.2019.01049/full

Retrograde activation of CB1R by muscarinic receptors protects against central organophosphorus toxicity.

Neuropharmacology“The acute toxicity of organophosphorus-based compounds is primarily a result of acetylcholinesterase inhibition in the central and peripheral nervous systems. The resulting cholinergic crisis manifests as seizure, paralysis, respiratory failure and neurotoxicity. Though overstimulation of muscarinic receptors is the mechanistic basis of central organophosphorus (OP) toxicities, short-term changes in synapse physiology that precede OP-induced seizures have not been investigated in detail. To study acute effects of OP exposure on synaptic function, field excitatory postsynaptic potentials (fEPSPs) were recorded from Schaffer collateral synapses in the mouse hippocampus CA1 stratum radiatum during perfusion with various OP compounds. Administration of the OPs paraoxon, soman or VX rapidly and stably depressed fEPSPs via a presynaptic mechanism, while the non-OP proconvulsant tetramethylenedisulfotetramine had no effect on fEPSP amplitudes. OP-induced presynaptic long-term depression manifested prior to interictal spiking, occurred independent of recurrent firing, and did not require NMDA receptor currents, suggesting that it was not mediated by activity-dependent calcium uptake. Pharmacological dissection revealed that the presynaptic endocannabinoid type 1 receptor (CB1R) as well as postsynaptic M1 and M3 muscarinic acetylcholine receptors were necessary for OP-LTD. Administration of CB1R antagonists significantly reduced survival in mice after a soman challenge, revealing an acute protective role for endogenous CB1R signaling during OP exposure. Collectively these data demonstrate that the endocannabinoid system alters glutamatergic synaptic function during the acute response to OP acetylcholinesterase inhibitors.”

https://www.ncbi.nlm.nih.gov/pubmed/31132436

“CB1R activation represents a novel therapy to mitigate acute OP toxicity”

https://www.sciencedirect.com/science/article/pii/S002839081930190X?via%3Dihub

5-Chlorobenzofuran-2-carboxamides: From allosteric CB1 modulators to potential apoptotic antitumor agents.

European Journal of Medicinal Chemistry“Cannabinoids as THC and the CB1 allosteric modulator CBD were reported to have antiproliferative activities with no reports for other CB1 allosteric modulators as the 5-chloroindole-2-carboxamide derivatives and their furan congeners. Based on the antiproliferative activity of two 5-chlorobenzofuran-2-carboxamide allosteric CB1 modulators, a series of novel derivatives was designed and synthesized. The synthesized compounds were tested in a cell viability assay using human mammary gland epithelial cell line (MCF-10A) where all the compounds exhibited no cytotoxic effects and more than 85% cell viability at a concentration of 50 μM. Some derivatives showed good antiproliferative activities against tumor cells as compounds 8, 15, 21 and 22. The most active compound 15 showed equipotent activity to doxorubicin. Compounds 7, 9, 15, 16, 21 and 22 increased the level of active caspase 3 by 4-8 folds, compared to the control cells in MCF-7 cell line and doxorubicin as a reference drug. Compounds 15 and 21, the most activecaspase-3 inducers, increase the levels of caspase 8 and 9 indicating activation of both intrinsic and extrinsic pathways and showed potent induction of Bax, down-regulation of Bcl-2 protein levels and over-expression of Cytochrome C levels in MCF-7 cell lines. Compound 15 exhibited cell cycle arrest at the Pre-G1 and G2/M phases in the cell cycle analysis of MCF-7 cell line. The drug Likeness profile of the synthesized compounds showed that all the compounds were predicted to have high oral absorption complying with different pharmacokinetics filters.”

https://www.ncbi.nlm.nih.gov/pubmed/31128433

https://www.sciencedirect.com/science/article/pii/S0223523419304507?via%3Dihub