Endocannabinoid system and adult neurogenesis: a focused review.

Current Opinion in Pharmacology“The endocannabinoid system (eCB) is a ubiquitous lipid signaling system composed of at least two receptors, their endogenous ligands, and the enzymes responsible for their synthesis and degradation. Within the brain, the eCB system is highly expressed in the hippocampus and controls basic biological processes, including neuronal proliferation, migration and differentiation, which are intimately linked with embryonal neurogenesis. Accumulated preclinical evidence has indicated that eCBs play a major role also in regulating adult neurogenesis. Increased cannabinoid receptor activity, either by increased eCB content or by pharmacological blockade of their degradation, produces neurogenic effects alongside rescue of phenotypes in animal models of different psychiatric and neurological disorders. Therefore, in the light of the higher therapeutic potential of adult neurogenesis compared to the embryonic one, here we sought to summarize the most recent evidence pointing towards a neurogenic role for eCBs in the adult brain, both under normal and pathological conditions.”

https://www.ncbi.nlm.nih.gov/pubmed/31864101

“The endocannabinoid system is involved in all aspects of the biology of neural stem cells. Selective CB1 and CB2 agonism produces pro-neurogenic effects in different models of brain insults. Further research is needed to characterize the eCB system as a new druggable target for neurogenesis-related diseases.”

https://www.sciencedirect.com/science/article/pii/S1471489219301122?via%3Dihub

Endocannabinoid System in the Airways.

molecules-logo“Cannabinoids and the mammalian endocannabinoid system is an important research area of interest and attracted many researchers because of their widespread biological effects. The significant immune-modulatory role of cannabinoids has suggested their therapeutic use in several inflammatory conditions. Airways are prone to environmental irritants and stimulants, and increased inflammation is an important process in most of the respiratory diseases. Therefore, the main strategies for treating airway diseases are suppression of inflammation and producing bronchodilation. The ability of cannabinoids to induce bronchodilation and modify inflammation indicates their importance for airway physiology and pathologies. In this review, the contribution of cannabinoids and the endocannabinoid system in the airways are discussed, and the existing data for their therapeutic use in airway diseases are presented.”

https://www.ncbi.nlm.nih.gov/pubmed/31861200

https://www.mdpi.com/1420-3049/24/24/4626

Stress-induced modulation of endocannabinoid signaling leads to delayed strengthening of synaptic connectivity in the amygdala.

Image result for pnas“Even a brief exposure to severe stress strengthens synaptic connectivity days later in the amygdala, a brain area implicated in the affective symptoms of stress-related psychiatric disorders. However, little is known about the synaptic signaling mechanisms during stress that eventually culminate in its delayed impact on the amygdala. Hence, we investigated early stress-induced changes in amygdalar synaptic signaling in order to prevent its delayed effects.

Whole-cell recordings in basolateral amygdala (BLA) slices from rats revealed higher frequency of miniature excitatory postsynaptic currents (mEPSCs) immediately after 2-h immobilization stress. This was replicated by inhibition of cannabinoid receptors (CB1R), suggesting a role for endocannabinoid (eCB) signaling.

Stress also reduced N-arachidonoylethanolamine (AEA), an endogenous ligand of CB1R. Since stress-induced activation of fatty acid amide hydrolase (FAAH) reduces AEA, we confirmed that oral administration of an FAAH inhibitor during stress prevents the increase in synaptic excitation in the BLA soon after stress.

Although stress also caused an immediate reduction in synaptic inhibition, this was not prevented by FAAH inhibition. Strikingly, FAAH inhibition during the traumatic stressor was also effective 10 d later on the delayed manifestation of synaptic strengthening in BLA neurons, preventing both enhanced mEPSC frequency and increased dendritic spine-density.

Thus, oral administration of an FAAH inhibitor during a brief stress prevents the early synaptic changes that eventually build up to hyperexcitability in the amygdala. This framework is of therapeutic relevance because of growing interest in targeting eCB signaling to prevent the gradual development of emotional symptoms and underlying amygdalar dysfunction triggered by traumatic stress.”

https://www.ncbi.nlm.nih.gov/pubmed/31843894

https://www.pnas.org/content/early/2019/12/13/1910322116

Exploiting cannabinoid and vanilloid mechanisms for epilepsy treatment.

“This review focuses on the possible roles of phytocannabinoids, synthetic cannabinoids, endocannabinoids, and “transient receptor potential cation channel, subfamily V, member 1” (TRPV1) channel blockers in epilepsy treatment.

The phytocannabinoids are compounds produced by the herb Cannabis sativa, from which Δ9-tetrahydrocannabinol (Δ9-THC) is the main active compound. The therapeutic applications of Δ9-THC are limited, whereas cannabidiol (CBD), another phytocannabinoid, induces antiepileptic effects in experimental animals and in patients with refractory epilepsies.

Synthetic CB1 agonists induce mixed effects, which hamper their therapeutic applications. A more promising strategy focuses on compounds that increase the brain levels of anandamide, an endocannabinoid produced on-demand to counteract hyperexcitability. Thus, anandamide hydrolysis inhibitors might represent a future class of antiepileptic drugs. Finally, compounds that block the TRPV1 (“vanilloid”) channel, a possible anandamide target in the brain, have also been investigated.

In conclusion, the therapeutic use of phytocannabinoids (CBD) is already in practice, although its mechanisms of action remain unclear. Endocannabinoid and TRPV1 mechanisms warrant further basic studies to support their potential clinical applications.”

https://www.ncbi.nlm.nih.gov/pubmed/31839498

“Cannabidiol is in clinical use for refractory epilepsies.”

https://www.epilepsybehavior.com/article/S1525-5050(19)30373-7/fulltext

Medicinal Use of Cannabis in Children and Pregnant Women.

 Image result for Rambam Maimonides Med J.“The increasing medicinal use of cannabis during recent years has largely overlooked children and pregnant women due to litigious and ethical concerns.

However, over the last few years medicine has observed increasing numbers of children treated with cannabis for autism spectrum disorder (ASD) and fetal alcohol spectrum disorder (FASD), and pregnant women treated for hyperemesis gravidarum (HG).

This review provides an account of major findings discovered through this research.

Specifically, cannabis may offer therapeutic advantages to behavioral symptoms of autism spectrum disorder and fetal alcohol spectrum disorder, and to the severe nausea and vomiting in hyperemesis gravidarum.

The use of medical cannabis in children and pregnant women should be further discussed and researched in this patient population.”

https://www.ncbi.nlm.nih.gov/pubmed/31826800

Cannabinoids and the expanded endocannabinoid system in neurological disorders.

 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

Therapeutic potential of natural psychoactive drugs for central nervous system disorders: A perspective from polypharmacology.

“In drug development, the creation of highly selective ligands has been unsuccessful for the treatment of central nervous system disorders.

Multi-target ligands, from the polypharmacology paradigm, are being proposed as treatments for these complex disorders, since they offer enhanced efficacy and a strong safety profile.

Natural products are the best examples of multi-target compounds, so they are of high interest within this paradigm.

Additionally, recent research on psychoactive drugs of natural origin, such as ayahuasca and cannabis, has demonstrated promising therapeutic potential for the treatment of some psychiatric and neurological disorders.

In this text, we describe how research on psychoactive drugs can be effectively combined with the polypharmacology paradigm, providing ayahuasca and cannabis research as examples.”

https://www.ncbi.nlm.nih.gov/pubmed/31830883

http://www.eurekaselect.com/177382/article

Cannabis-based medicines and the perioperative physician.

Image result for perioperative medicine

“Cannabis use for medicinal purposes was first documented in 2900 BC in China, when Emperor Shen Nong described benefit for rheumatism and malaria and later in Ancient Egyptian texts.

Discussion in medical journals, the mainstream and social media around the use of cannabis for medicinal and non-medicinal purposes has increased recently, especially following the legalisation of cannabis for recreational use in Canada and the UK government’s decision to make cannabis-based medicines (CBMs) available for prescription by doctors on the specialist register.

The actual, social and economic legitimisation of cannabis and its medicinal derivatives makes it likely increasing numbers of patients will present on this class of medicines. Perioperative physicians will require a sound understanding of their pharmacology and evidence base, and may wish to exploit this group of compounds for therapeutic purposes in the perioperative period.

The increasing availability of cannabis for both recreational and medicinal purposes means that anaesthetists will encounter an increasing number of patients taking cannabis-based medications. The existing evidence base is conflicted and incomplete regarding the indications, interactions and long-term effects of these substances.

Globally, most doctors have had little education regarding the pharmacology of cannabis-based medicines, despite the endocannabinoid system being one of the most widespread in the human body.

Much is unknown, and much is to be decided, including clarifying definitions and nomenclature, and therapeutic indications and dosing. Anaesthetists, Intensivists, Pain and Perioperative physicians will want to contribute to this evidence base and attempt to harness such therapeutic benefits in terms of pain relief and opiate-avoidance, anti-emesis and seizure control.

We present a summary of the pharmacology of cannabis-based medicines including anaesthetic interactions and implications, to assist colleagues encountering these medicines in clinical practice.”

https://www.ncbi.nlm.nih.gov/pubmed/31827774

“In summary, cannabinoids may improve pain relief as part of multi-modal approach. As the evidence base increases, CBMs could become part of the perioperative teams’ armamentarium to help provide an opiate sparing multimodal analgesia regime as well as having a role in the management of common post-operative complications such as nausea and vomiting.”

 https://perioperativemedicinejournal.biomedcentral.com/articles/10.1186/s13741-019-0127-x

Gastrointestinal Adverse Events of Cannabinoid 1 Receptor Inverse Agonists suggest their Potential Use in Irritable Bowel Syndrome with Constipation: A Systematic Review and Meta-Analysis.

 Image result for J Gastrointestin Liver Dis“Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal (GI) disorders characterized by pain and impaired bowel movements. Currently available drugs show limited efficacy.

Cannabinoid 1 receptor (CB1) inverse agonists (CB1-RAN) cause diarrhea and may be candidates for the treatment of constipation-predominant IBS (IBS-C). We evaluated the effects of CB1-RAN in clinical trials for their potential use in IBS-C.

METHODS:

Database search identified all clinical trials published up to May 2018 that reported rimonabant and taranabant treatment for at least one month and detailed the GI adverse events (AEs). Categorical outcomes (subgroups of AEs) were analyzed using the odds ratio (OR).

RESULTS:

Eighteen trials met the inclusion criteria. Rimonabant 20 mg produced significantly more overall AEs (OR=1.35, CI: 1.19-1.52, p<0.0001), psychiatric events (OR=1.79, CI: 1.46-2.21, p<0.001) and GI AEs (OR=2.05, CI: 1.65-2.55, p<0.001) compared to placebo. Taranabant at doses ranging from 0.5 to 8 mg produced significantly more overall AEs (OR=1.36, CI: 1.13-1.64, p<0.002), psychiatric AEs (1.82, CI: 1.54-2.16, p<0.001) and GI AEs (OR=1.75, CI: 1.29-2.37, p<0.001) compared to placebo.

CONCLUSIONS:

The approach to target CB1 in the gut for the treatment of IBS-C or chronic constipation seems a promising therapeutic option. Prospective clinical trials on the possible targeting of CB1 and the endocannabinoid system are warranted.”

https://www.ncbi.nlm.nih.gov/pubmed/31826058

https://www.jgld.ro/jgld/index.php/jgld/article/view/265

Activation of Cannabinoid Receptors Attenuates Endothelin-1-induced Mitochondrial Dysfunction in Rat Ventricular Myocytes.

Image result for Journal of Cardiovascular Pharmacology.“Evidence suggests that activation of the endocannabinoid system offers cardioprotection.

Aberrant energy production by impaired mitochondria purportedly contributes to various aspects of cardiovascular disease. We investigated whether cannabinoid (CB) receptor activation would attenuate mitochondrial dysfunction induced by endothelin-1 (ET1).

Acute exposure to ET1 (4 h) in the presence of palmitate as primary energy substrate induced mitochondrial membrane depolarization, and decreased mitochondrial bioenergetics and expression of genes related to fatty acid oxidation (i.e. peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1α, a driver of mitochondrial biogenesis, and carnitine palmitoyltransferase (CPT)-1β, facilitator of fatty acid uptake).

A CB1/CB2 dual agonist with limited brain penetration, CB-13, corrected these parameters. AMP-activated protein kinase (AMPK), an important regulator of energy homeostasis, mediated the ability of CB-13 to rescue mitochondrial function. In fact, the ability of CB-13 to rescue fatty acid oxidation-related bioenergetics, as well as expression of PGC-1α and CPT-1β, was abolished by pharmacological inhibition of AMPK using compound C and shRNA knockdown of AMPKα1/α2, respectively.

Interventions that target CB/AMPK signaling might represent a novel therapeutic approach to address the multi-factorial problem of cardiovascular disease.”

https://www.ncbi.nlm.nih.gov/pubmed/31815823

https://insights.ovid.com/crossref?an=00005344-900000000-98463