The Use of Cannabis for Headache Disorders.

Mary Ann Liebert, Inc. publishers

“Headache disorders are common, debilitating, and, in many cases, inadequately managed by existing treatments. Although clinical trials of cannabis for neuropathic pain have shown promising results, there has been limited research on its use, specifically for headache disorders. This review considers historical prescription practices, summarizes the existing reports on the use of cannabis for headache, and examines the preclinical literature exploring the role of exogenous and endogenous cannabinoids to alter headache pathophysiology. Currently, there is not enough evidence from well-designed clinical trials to support the use of cannabis for headache, but there are sufficient anecdotal and preliminary results, as well as plausible neurobiological mechanisms, to warrant properly designed clinical trials. Such trials are needed to determine short- and long-term efficacy for specific headache types, compatibility with existing treatments, optimal administration practices, as well as potential risks.” https://www.ncbi.nlm.nih.gov/pubmed/28861505

“Preclinical studies examining the role of the endocannabinoid system in migraine pathogenesis also suggest a potential therapeutic value for cannabis in the treatment of headache. It has been postulated that a general deficiency in endocannabinoid tone could underlie headache disorders.” http://online.liebertpub.com/doi/10.1089/can.2016.0033

An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies.

Mary Ann Liebert, Inc. publishers

“This literature survey aims to extend the comprehensive survey performed by Bergamaschi et al. in 2011 on cannabidiol (CBD) safety and side effects. Apart from updating the literature, this article focuses on clinical studies and CBD potential interactions with other drugs.

Results: In general, the often described favorable safety profile of CBD in humans was confirmed and extended by the reviewed research. The majority of studies were performed for treatment of epilepsy and psychotic disorders. Here, the most commonly reported side effects were tiredness, diarrhea, and changes of appetite/weight. In comparison with other drugs, used for the treatment of these medical conditions, CBD has a better side effect profile. This could improve patients’ compliance and adherence to treatment. CBD is often used as adjunct therapy. Therefore, more clinical research is warranted on CBD action on hepatic enzymes, drug transporters, and interactions with other drugs and to see if this mainly leads to positive or negative effects, for example, reducing the needed clobazam doses in epilepsy and therefore clobazam’s side effects.

Conclusion: This review also illustrates that some important toxicological parameters are yet to be studied, for example, if CBD has an effect on hormones. Additionally, more clinical trials with a greater number of participants and longer chronic CBD administration are still lacking.”

Tetrahydrocannabinolic acid is a potent PPARγ agonist with neuroprotective activity.

British Journal of Pharmacology

“Phytocannabinoids are produced in Cannabis sativa L. in acidic form and are decarboxylated upon heating, processing, and storage. While the biological effects of decarboxylated cannabinoids such as Δ9 -tetrahydrocannabinol (Δ9 -THC) have been extensively investigated, the bioactivity of Δ9 -THCA is largely unknown, despite its occurrence in different Cannabis preparations. The aim of this study was to determine whether Δ9 -THCA modulates the PPARγ pathway and has neuroprotective activity.

The effects of six phytocannabinoids on PPARγ binding and transcriptional activity were investigated. The effect of Δ9 -THCA on mitochondrial biogenesis and PGC-1α expression was investigated in N2a cells. The neuroprotective effect was analysed in STHdhQ111/Q111 cells expressing a mutated form of the huntingtin protein, and in N2a cells infected with an adenovirus carrying human huntingtin containing 94 polyQ repeats (mHtt-q94). In vivo neuroprotective activity of Δ9 -THCA was investigated in mice intoxicated with the mitochondrial toxin 3-nitropropionic acid (3-NP).

KEY RESULTS:

Cannabinoid acids bind and activate PPARγ with higher potency than their decarboxylated products. Δ9 -THCA increases mitochondrial mass in neuroblastoma N2a cells, and prevents cytotoxicity induced by serum deprivation in STHdhQ111/Q111cells and by mutHtt-q94 in N2a cells. Δ9 -THCA, through a PPARγ-dependent pathway, was neuroprotectant in mice intoxicated with 3-NP, improving motor deficits and preventing striatal degeneration. In addition, Δ9 -THCA attenuated microgliosis, astrogliosis and the upregulation of proinflammatory markers induced by 3-NP.

CONCLUSION AND IMPLICATIONS:

Δ9 -THCA shows potent neuroprotective activity, worth consideration for the treatment of Huntington´s Disease and possibly other neurodegenerative and neuroinflammatory diseases.”

https://www.ncbi.nlm.nih.gov/pubmed/28853159

http://onlinelibrary.wiley.com/doi/10.1111/bph.14019/abstract

Receptor-heteromer mediated regulation of endocannabinoid signaling in activated microglia. Role of CB1 and CB2 receptors and relevance for Alzheimer’s disease and levodopa-induced dyskinesia.

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“Endocannabinoids are important regulators of neurotransmission and, acting on activated microglia, they are postulated as neuroprotective agents. Endocannabinoid action is mediated by CB1 and CB2 receptors, which may form heteromeric complexes (CB1-CB2Hets) with unknown function in microglia.

We aimed at establishing the expression and signaling properties of cannabinoidreceptors in resting and LPS/IFN-γ-activated microglia. Unlike CB1, CB2 receptors and CB1-CB2Hets were upregulated in activated microglia. Resting cell refractory CB2 receptors became robustly coupled to Gi in activated cells, in which CB1-CB2Hets mediated a positive cross-talk. Resting cells were refractory while activated cells were highly responsive to cannabinoids. Interestingly, similar results were obtained in cultures treated with ß-amyloid (Aß1-42). Activation microglial markers were detected in the striatum of a Parkinson’s disease (PD) model and, remarkably, in primary microglia cultures from the hippocampus of mutant β-amyloid precursor protein (APPSw,Ind) mice, a transgenic Alzheimer’s disease (AD) model. Also of note was the similar cannabinoid receptor signaling found in primary cultures of microglia from APPSw,Ind and in cells from control animals activated using LPS plus IFN- γ. Expression of CB1-CB2Hets was increased in the striatum from rats rendered dyskinetic by chronic levodopa treatment.

In summary, our results showed sensitivity of activated microglial cells to cannabinoids, increased CB1-CB2Het expression in activated microglia and in microglia from the hippocampus of an AD model, and a correlation between levodopa-induced dyskinesia and striatal microglial activation in a PD model. Cannabinoid receptors and the CB1-CB2 heteroreceptor complex in activated microglia have potential as targets in the treatment of neurodegenerative diseases.”

https://www.ncbi.nlm.nih.gov/pubmed/28843453

http://www.sciencedirect.com/science/article/pii/S0889159117304038

The potential role of cannabinoids in epilepsy treatment.

Publication Cover

“Epilepsy is one of the world’s oldest recognized and prevalent neurological diseases. It has a great negative impact on patients’ quality of life (QOL) as a consequence of treatment resistant seizures in about 30% of patients together with drugs’ side effects and comorbidities. Therefore, new drugs are needed and cannabinoids, above all cannabidiol, have recently gathered attention.

This review summarizes the scientific data from human and animal studies on the major cannabinoids which have been of interest in the treatment of epilepsy, including drugs acting on the endocannabinoid system.

Despite the fact that cannabis has been used for many purposes over 4 millennia, the development of drugs based on cannabinoids has been very slow. Only recently, research has focused on their potential effects and CBD is the first treatment of this group with clinical evidence of efficacy in children with Dravet syndrome; moreover, other studies are currently ongoing to confirm its effectiveness in patients with epilepsy.

On the other hand, it will be of interest to understand whether drugs acting on the endocannabinoid system will be able to reach the market and prove their known preclinical efficacy also in patients with epilepsy.”

https://www.ncbi.nlm.nih.gov/pubmed/28845714   http://www.tandfonline.com/doi/abs/10.1080/14737175.2017.1373019

 

“The role of cannabinoids and endocannabinoid system in the treatment of epilepsy. Cannabis has been used for thousands of years in the treatment of various diseases. Cannabinoids have been shown in preliminary animal model studies and in studies of patients with epilepsy to have antiepileptic activity. ” https://www.degruyter.com/view/j/joepi.ahead-of-print/joepi-2015-0034/joepi-2015-0034.xml
“Phytocannabinoids produce anticonvulsant effects through the endocannabinoid system, with few adverse effects.”

Cannabinoids as Anticancer Drugs.

Advances in Pharmacology

“The endocannabinoid system encompassing cannabinoid receptors, endogenous receptor ligands (endocannabinoids), as well as enzymes conferring the synthesis and degradation of endocannabinoids has emerged as a considerable target for pharmacotherapeutical approaches of numerous diseases. Besides palliative effects of cannabinoids used in cancer treatment, phytocannabinoids, synthetic agonists, as well as substances that increase endogenous endocannabinoid levels have gained interest as potential agents for systemic cancer treatment. Accordingly, cannabinoid compounds have been reported to inhibit tumor growth and spreading in numerous rodent models. The underlying mechanisms include induction of apoptosis, autophagy, and cell cycle arrest in tumor cells as well as inhibition of tumor cell invasion and angiogenic features of endothelial cells. In addition, cannabinoids have been shown to suppress epithelial-to-mesenchymal transition, to enhance tumor immune surveillance, and to support chemotherapeutics’ effects on drug-resistant cancer cells. However, unwanted side effects include psychoactivity and possibly pathogenic effects on liver health. Other cannabinoids such as the nonpsychoactive cannabidiol exert a comparatively good safety profile while exhibiting considerable anticancer properties. So far experience with anticarcinogenic effects of cannabinoids is confined to in vitro studies and animal models. Although a bench-to-bedside conversion remains to be established, the current knowledge suggests cannabinoid compounds to serve as a group of drugs that may offer significant advantages for patients suffering from cancer diseases. The present review summarizes the role of the endocannabinoid system and cannabinoid compounds in tumor progression.”

https://www.ncbi.nlm.nih.gov/pubmed/28826542

http://www.sciencedirect.com/science/article/pii/S105435891730039X?via%3Dihub

Cannabis Pharmacology: The Usual Suspects and a Few Promising Leads.

Advances in Pharmacology

“The golden age of cannabis pharmacology began in the 1960s as Raphael Mechoulam and his colleagues in Israel isolated and synthesized cannabidiol, tetrahydrocannabinol, and other phytocannabinoids. Initially, THC garnered most research interest with sporadic attention to cannabidiol, which has only rekindled in the last 15 years through a demonstration of its remarkably versatile pharmacology and synergy with THC. Gradually a cognizance of the potential of other phytocannabinoids has developed. Contemporaneous assessment of cannabis pharmacology must be even far more inclusive. Medical and recreational consumers alike have long believed in unique attributes of certain cannabis chemovars despite their similarity in cannabinoid profiles. This has focused additional research on the pharmacological contributions of mono- and sesquiterpenoids to the effects of cannabis flower preparations. Investigation reveals these aromatic compounds to contribute modulatory and therapeutic roles in the cannabis entourage far beyond expectations considering their modest concentrations in the plant. Synergistic relationships of the terpenoids to cannabinoids will be highlighted and include many complementary roles to boost therapeutic efficacy in treatment of pain, psychiatric disorders, cancer, and numerous other areas. Additional parts of the cannabis plant provide a wide and distinct variety of other compounds of pharmacological interest, including the triterpenoid friedelin from the roots, canniprene from the fan leaves, cannabisin from seed coats, and cannflavin A from seed sprouts. This chapter will explore the unique attributes of these agents and demonstrate how cannabis may yet fulfil its potential as Mechoulam’s professed “pharmacological treasure trove.””

https://www.ncbi.nlm.nih.gov/pubmed/28826544

http://www.sciencedirect.com/science/article/pii/S1054358917300273?via%3Dihub

Is the Cannabinoid CB2 Receptor a Major Regulator of the Neuroinflammatory Axis of the Neurovascular Unit in Humans?

Elsevier

“The central nervous system (CNS) is an immune privileged site where the neurovascular unit (NVU) and the blood-brain barrier (BBB) act as a selectively permeable interface to control the passage of nutrients and inflammatory cells into the brain parenchyma. However, in response to injury, infection, or disease, CNS cells become activated, and release inflammatory mediators to recruit immune cells to the site of inflammation.

Increasing evidence suggests that cannabinoids may have a neuroprotective role in CNS inflammatory conditions.

For many years, it was widely accepted that cannabinoid receptor type 1 (CB1) modulates neurological function centrally, while peripheral cannabinoid receptor type 2 (CB2) modulates immune function.

As knowledge about the physiology and pharmacology of the endocannabinoid system advances, there is increasing interest in targeting CB2 as a potential treatment for inflammation-dependent CNS diseases (Ashton & Glass, 2007), where recent rodent and human studies have implicated intervention at the level of the NVU and BBB.

These are incredibly important in brain health and disease. Therefore, this review begins by explaining the cellular and molecular components of these systems, highlighting important molecules potentially regulated by cannabinoid ligands and then takes an unbiased look at the evidence in support (or otherwise) of cannabinoid receptor expression and control of the NVU and BBB function in humans.”

https://www.ncbi.nlm.nih.gov/pubmed/28826541

http://www.sciencedirect.com/science/article/pii/S1054358917300376?via%3Dihub

The effects of cannabinoid receptors activation and glucocorticoid receptors deactivation in the amygdala and hippocampus on the consolidation of a traumatic event.

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“Ample evidence demonstrates that fear learning contributes significantly to many anxiety pathologies including post-traumatic stress disorder (PTSD). The endocannabinoid (eCB) system may offer therapeutic benefits for PTSD and it is a modulator of the hypothalamic pituitary adrenal (HPA) axis.

Here we compared the separated and combined effects of blocking glucocorticoid receptors (GRs) using the GR antagonist RU486 and enhancing CB1r signaling using the CB1/2 receptor agonist WIN55,212-2 in the CA1 and basolateral amygdala (BLA) on the consolidation of traumatic memory. Traumatic memory was formed by exposure to a severe footshock in an inhibitory avoidance apparatus followed by exposure to trauma reminders. Intra-BLA RU486 (10 ng/side) and WIN55,212-2 (5 μg/side) administered immediately after shock exposure dampened the consolidation of the memory about the traumatic event and attenuated the increase in acoustic startle response in rats exposed to shock and reminders. In the CA1, WIN55,212-2 impaired consolidation and attenuated the increase in acoustic startle response whereas RU486 had no effect. The effects of WIN55,212-2 were found to be mediated by CB1 receptors, but not by GRs. Moreover, post-shock systemic WIN55,212-2 (0.5 mg/kg) administration prevented the increase in GRs and CB1 receptor levels in the CA1 and BLA in rats exposed to shock and reminders.

The findings suggest that the BLA is a locus of action of cannabinoids and glucocorticoids in modulating consolidation of traumatic memory in a rat model of PTSD. Also, the findings highlight novel targets for the treatment of emotional disorders and PTSD in particular.”

https://www.ncbi.nlm.nih.gov/pubmed/28818702

http://www.sciencedirect.com/science/article/pii/S1074742717301284

Anticonvulsant effect of cannabidiol in the pentylenetetrazole model: Pharmacological mechanisms, electroencephalographic profile, and brain cytokine levels.

“Cannabidiol (CBD), the main nonpsychotomimetic compound from Cannabis sativa, inhibits experimental seizures in animal models and alleviates certain types of intractable epilepsies in patients.

Here we tested the hypothesis that CBD anticonvulsant mechanisms are prevented by cannabinoid (CB1 and CB2) and vanilloid (TRPV1) receptor blockers. We also investigated its effects on electroencephalographic (EEG) activity and hippocampal cytokines in the pentylenetetrazole (PTZ) model.

Pretreatment with CBD (60mg/kg) attenuated seizures induced by intraperitoneal, subcutaneous, and intravenous PTZ administration in mice. The effects were reversed by CB1, CB2, and TRPV1 selective antagonists (AM251, AM630, and SB366791, respectively). Additionally, CBD delayed seizure sensitization resulting from repeated PTZ administration (kindling). This cannabinoid also prevented PTZ-induced EEG activity and interleukin-6 increase in prefrontal cortex.

In conclusion, the robust anticonvulsant effects of CBD may result from multiple pharmacological mechanisms, including facilitation of endocannabinoid signaling and TRPV1 mechanisms. These findings advance our understanding on CBD inhibition of seizures, EEG activity, and cytokine actions, with potential implications for the development of new treatments for certain epileptic syndromes.”

https://www.ncbi.nlm.nih.gov/pubmed/28821005

http://www.epilepsybehavior.com/article/S1525-5050(17)30322-0/fulltext