Regulation of noradrenergic and serotonergic systems by cannabinoids: relevance to cannabinoid-induced effects.

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“The cannabinoid system is composed of Gi/o protein-coupled cannabinoid type 1 receptor (CB1) and cannabinoid type 2 (CB2) receptor and endogenous compounds. The CB1 receptor is widely distributed in the central nervous system (CNS) and it is involved in the regulation of common physiological functions. At the neuronal level, the CB1 receptor is mainly placed at GABAergic and glutamatergic axon terminals, where it modulates excitatory and inhibitory synapses. To date, the involvement of CB2 receptor in the regulation of neurotransmission in the CNS has not been clearly shown. The majority of noradrenergic (NA) cells in mammalian tissues are located in the locus coeruleus (LC) while serotonergic (5-HT) cells are mainly distributed in the raphe nuclei including the dorsal raphe nucleus (DRN). In the CNS, NA and 5-HT systems play a crucial role in the control of pain, mood, arousal, sleep-wake cycle, learning/memory, anxiety, and rewarding behaviour. This review summarizes the electrophysiological, neurochemical and behavioural evidences for modulation of the NA/5-HT systems by cannabinoids and the CB1 receptor. Cannabinoids regulate the neuronal activity of NA and 5-HT cells and the release of NA and 5-HT by direct and indirect mechanisms. The interaction between cannabinoid and NA/5-HT systems may underlie several behavioural changes induced by cannabis such as anxiolytic and antidepressant effects or side effects (e.g. disruption of attention). Further research is needed to better understand different aspects of NA and 5-HT systems regulation by cannabinoids, which would be relevant for their use in therapeutics.”

https://www.ncbi.nlm.nih.gov/pubmed/29169951

http://www.sciencedirect.com/science/article/pii/S0024320517306069

Pharmacological Foundations of Cannabis Chemovars.

“An advanced Mendelian Cannabis breeding program has been developed utilizing chemical markers to maximize the yield of phytocannabinoids and terpenoids with the aim to improve therapeutic efficacy and safety.

Cannabis is often divided into several categories based on cannabinoid content. Type I, Δ9-tetrahydrocannabinol-predominant, is the prevalent offering in both medical and recreational marketplaces. In recent years, the therapeutic benefits of cannabidiol have been better recognized, leading to the promotion of additional chemovars: Type II, Cannabis that contains both Δ9-tetrahydrocannabinol and cannabidiol, and cannabidiol-predominant Type III Cannabis.

While high-Δ9-tetrahydrocannabinol and high-myrcene chemovars dominate markets, these may not be optimal for patients who require distinct chemical profiles to achieve symptomatic relief. Type II Cannabis chemovars that display cannabidiol- and terpenoid-rich profiles have the potential to improve both efficacy and minimize adverse events associated with Δ9-tetrahydrocannabinol exposure. Cannabis samples were analyzed for cannabinoid and terpenoid content, and analytical results are presented via PhytoFacts, a patent-pending method of graphically displaying phytocannabinoid and terpenoid content, as well as scent, taste, and subjective therapeutic effect data.

Examples from the breeding program are highlighted and include Type I, II, and III Cannabis chemovars, those highly potent in terpenoids in general, or single components, for example, limonene, pinene, terpinolene, and linalool. Additionally, it is demonstrated how Type I - III chemovars have been developed with conserved terpenoid proportions. Specific chemovars may produce enhanced analgesia, anti-inflammatory, anticonvulsant, antidepressant, and anti-anxiety effects, while simultaneously reducing sequelae of Δ9-tetrahydrocannabinol such as panic, toxic psychosis, and short-term memory impairment.”

https://www.ncbi.nlm.nih.gov/pubmed/29161743

https://www.thieme-connect.de/DOI/DOI?10.1055/s-0043-122240

Cannabinoid Receptor Type 1 Agonist ACEA Protects Neurons from Death and Attenuates Endoplasmic Reticulum Stress-Related Apoptotic Pathway Signaling.

Neurotoxicity Research

“Neurodegeneration is the result of progressive destruction of neurons in the central nervous system, with unknown causes and pathological mechanisms not yet fully elucidated. Several factors contribute to neurodegenerative processes, including neuroinflammation, accumulation of neurotoxic factors, and misfolded proteins in the lumen of the endoplasmic reticulum (ER).

Endocannabinoid signaling has been pointed out as an important modulatory system in several neurodegeneration-related processes, inhibiting the inflammatory response and increasing neuronal survival. Thus, we investigated the presumptive protective effect of the selective cannabinoid type 1 (CB1) receptor agonist) against inflammatory (lipopolysaccharide, LPS) and ER stress (tunicamycin) stimuli in an in vitro neuronal model (Neuro-2a neuroblastoma cells). Cell viability analysis revealed that ACEA was able to protect against cell death induced by LPS and tunicamycin.

This neuroprotective effect occurs via the CB1 receptor in the inflammation process and via the transient receptor potential of vanilloid type-1 (TRPV1) channel in ER stress. Furthermore, the immunoblotting analyses indicated that the neuroprotective effect of ACEA seems to involve the modulation of eukaryotic initiation factor 2 (eIF2α), transcription factor C/EBP homologous protein (CHOP), and caspase 12, as well as the survival/death p44/42 MAPK, ERK1/2-related signaling pathways.

Together, these data suggest that the endocannabinoid system is a potential therapeutic target in neurodegenerative processes, especially in ER-related neurodegenerative diseases.”

https://www.ncbi.nlm.nih.gov/pubmed/29134561

https://link.springer.com/article/10.1007%2Fs12640-017-9839-1

Involvement of cannabinoid receptor type 2 in light-induced degeneration of cells from mouse retinal cell line in vitro and mouse photoreceptors in vivo.

Experimental Eye Research

“Earlier studies showed that the expressions of the agonists of the cannabinoid receptors are reduced in the vitreous humor of patients with age-related macular degeneration (AMD), and the cannabinoid type 2 receptor is present in the retinas of rats and monkeys. The purpose of this study was to determine whether the cannabinoid type 2 receptor is involved in the light-induced death of cultured 661W cells, an immortalized murine retinal cell line, and in the light-induced retinal degeneration in mice.

Time-dependent changes in the expression and location of retinal cannabinoid type 2 receptor were determined by Western blot and immunostaining. The cannabinoid type 2 receptor was down-regulated in murine retinae and cone cells. In the in vitro studies, HU-308, a cannabinoidtype 2 receptor agonist, had a protective effect on the light-induced death of 661W cells, and this effect was attenuated by SR144528, a cannabinoid type 2 receptor antagonist.

Because the cannabinoid type 2 receptor is a G-protein coupled receptor and is coupled with Gi/o protein, we investigated the effects of the cAMP-dependent protein kinase (PKA). HU-308 and H89, a PKA inhibitor, deactivated PKA in retinal cone cells, and H89 also suppressed light-induced cell death. For the in vivo studies, a cannabinoid type 2 receptor agonist, HU-308, or an antagonist, SR144528, was injected intravitreally into mouse eyes before the light exposure. Electroretinography was used to determine the physiological status of the retinas. Injection of HU-308 improved the a- and b-waves of the ERGs and also the thickness of the outer nuclear layer of the murine retina after light exposure.

These findings indicate that the cannabinoid type 2 receptor is involved in the light-induced retinal damage through PKA signaling. Thus, activation of cannabinoidtype 2 receptor may be a therapeutic approach for light-associated retinal diseases.”

https://www.ncbi.nlm.nih.gov/pubmed/29133122

http://www.sciencedirect.com/science/article/pii/S0014483516304456?via%3Dihub

Single-Dose Pharmacokinetics of Oral Cannabidiol Following Administration of PTL101: A New Formulation Based on Gelatin Matrix Pellets Technology.

Clinical Pharmacology in Drug Development

“Cannabidiol (CBD) is the main nonpsychoactive component of the cannabis plant. It has been associated with antiseizure, antioxidant, neuroprotective, anxiolytic, anti-inflammatory, antidepressant, and antipsychotic effects.

PTL101 is an oral gelatin matrix pellets technology-based formulation containing highly purified CBD embedded in seamless gelatin matrix beadlets. Study objectives were to evaluate the safety and tolerability of PTL101 containing 10 and 100 mg CBD, following single administrations to healthy volunteers and to compare the pharmacokinetic profiles and relative bioavailability of CBD with Sativex oromucosal spray (the reference product) in a randomized, crossover study design.

Administration of PTL101 containing 10 CBD, led to a 1.7-fold higher Cmax and 1.3-fold higher AUC compared with the oromucosal spray. Tmax following both modes of delivery was 3-3.5 hours postdosing. CBD exhibited about a 1-hour lag in absorption when delivered via PTL101. A 10-fold increase in the dose resulted in an ∼15-fold increase in Cmax and AUC. Bioavailability of CBD in the 10-mg PTL101 dose was 134% relative to the reference spray.

PTL101 is a pharmaceutical-grade, user-friendly oral formulation that demonstrated safe and efficient delivery of CBD and therefore could be an attractive candidate for therapeutic indications.”

https://www.ncbi.nlm.nih.gov/pubmed/29125702

http://onlinelibrary.wiley.com/doi/10.1002/cpdd.408/abstract

Pharmacotherapy of Apnea by Cannabimimetic Enhancement, the PACE Clinical Trial: Effects of Dronabinol in Obstructive Sleep Apnea.

Oxford University Press

“There remains an important and unmet need for fully effective and acceptable treatments in obstructive sleep apnea (OSA). At present, there are no approved drug treatments. Dronabinol has shown promise for OSA pharmacotherapy in a small dose-escalation pilot study.

Here, we present initial findings of the Phase II PACE (Pharmacotherapy of Apnea by Cannabimimetic Enhancement) trial, a fully-blinded parallel groups, placebo-controlled randomized trial of dronabinol in patients with moderate or severe OSA.

These findings support the therapeutic potential of cannabinoids in patients with OSA. In comparison to placebo, dronabinol was associated with lower AHI, improved subjective sleepiness and greater overall treatment satisfaction. Larger scale clinical trials will be necessary to clarify the best potential approach(es) to cannabinoid therapy in OSA”   https://www.ncbi.nlm.nih.gov/pubmed/29121334

“These findings support the therapeutic potential of cannabinoids in patients with obstructive sleep apnea (OSA).” https://academic.oup.com/sleep/article-abstract/doi/10.1093/sleep/zsx184/4600041?redirectedFrom=fulltext

Cannabinoid May Be First Drug for Sleep Apnea” https://www.medscape.com/viewarticle/891821

Efficacy and safety of cannabis for treating children with refractory epilepsy.

Nursing Children and Young People

“The aim of this literature review was to examine the evidence base for the safety and efficacy of cannabis in treating children with refractory epilepsy. Clinical and medical databases were searched and four articles were included in the final analysis, which included retrospective reviews and open-label trials with a total sample size of 424. One clinical trial included administration of cannabidiol, the non-psychoactive compound of cannabis, while the other three articles stated that the compound administered to participants contained tetrahydrocannabidiol, the psychoactive constituent of cannabis.

Cannabis may reduce seizures in some children and young people with refractory epilepsy, however, its success may be affected by aetiology of the epilepsy or concomitant anti-epileptic drug use, and a therapeutic dose has not been found. Positive side effects were also found including improved sleep, alertness and mood. More research is needed on this subject, including randomised controlled trials. Nurses who are aware of patients and families wishing to trial cannabis for refractory epilepsy should have full and frank discussions.”

https://www.ncbi.nlm.nih.gov/pubmed/29115760

https://journals.rcni.com/nursing-children-and-young-people/efficacy-and-safety-of-cannabis-for-treating-children-with-refractory-epilepsy-ncyp.2017.e907

Anti-migraine effect of ∆9-tetrahydrocannabinol in the female rat.

European Journal of Pharmacology

“Current anti-migraine treatments have limited efficacy and many side effects. Although anecdotal evidence suggests that marijuana is useful for migraine, this hypothesis has not been tested in a controlled experiment. Thus, the present study tested whether administration of ∆9-tetrahydrocannabinol (THC) produces anti-migraine effects in the female rat.

These data suggest that: 1) THC reduces migraine-like pain when administered at the right dose (0.32mg/kg) and time (immediately after AITC); 2) THC’s anti-migraine effect is mediated by CB1 receptors; and 3) Wheel running is an effective method to assess migraine treatments because only treatments producing antinociception without disruptive side effects will restore normal activity.

These findings support anecdotal evidence for the use of cannabinoids as a treatment for migraine in humans and implicate the CB1 receptor as a therapeutic target for migraine.”

https://www.ncbi.nlm.nih.gov/pubmed/29111112

http://www.sciencedirect.com/science/article/pii/S0014299917307239?via%3Dihub

Binding and Signaling Studies Disclose a Potential Allosteric Site for Cannabidiol in Cannabinoid CB2 Receptors.

 Image result for frontiers in pharmacology

“The mechanism of action of cannabidiol (CBD), the main non-psychotropic component of Cannabis sativa L., is not completely understood. First assumed that the compound was acting via cannabinoid CB2 receptors (CB2Rs) it is now suggested that it interacts with non-cannabinoid G-protein-coupled receptors (GPCRs); however, CBD does not bind with high affinity to the orthosteric site of any GPCR.

To search for alternative explanations, we tested CBD as a potential allosteric ligand of CB2R. Radioligand and non-radioactive homogeneous binding, intracellular cAMP determination and ERK1/2 phosphorylation assays were undertaken in heterologous systems expressing the human version of CB2R.

These results may help to understand CBD mode of action and may serve to revisit its therapeutic possibilities.”

https://www.ncbi.nlm.nih.gov/pubmed/29109685

https://www.frontiersin.org/articles/10.3389/fphar.2017.00744/full

Oral administration of cannabis with lipids leads to high levels of cannabinoids in the intestinal lymphatic system and prominent immunomodulation.

 

 

“Cannabidiol (CBD) and ∆9-tetrahydrocannabinol (THC) have well documented immunomodulatory effects in vitro, but not following oral administration in humans. Here we show that oral co-administration of cannabinoids with lipids can substantially increase their intestinal lymphatic transport in rats. Moreover, immune cells from MS patients were more susceptible to the immunosuppressive effects of cannabinoids than those from healthy volunteers or cancer patients. Therefore, administering cannabinoids with a high-fat meal or in lipid-based formulations has the potential to be a therapeutic approach to improve the treatment of MS, or indeed other autoimmune disorders.”  https://www.ncbi.nlm.nih.gov/pubmed/29109461

“Cannabis sativa has a very long history of medical use. In summary, it has been demonstrated in this work that oral co-administration of cannabis or cannabis-based medicines with lipids results in extremely high levels of lipophilic cannabinoids in the intestinal lymphatic system and prominent immunomodulatory effects. Therefore, administering cannabinoids with a high-fat meal, as cannabis-containing food, or in lipid-based formulations has the potential to be a therapeutic approach to improve the treatment of MS, or indeed other autoimmune disorders.”  https://www.nature.com/articles/s41598-017-15026-z