Mechanisms of action of cannabidiol in adoptively transferred experimental autoimmune encephalomyelitis

Cannabidiol Attenuates In Vivo Leukocyte Recruitment to the Spinal Cord Microvasculature at Peak Disease of Experimental Autoimmune Encephalomyelitis

Introduction: Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system characterized by neuroinflammation leading to demyelination. The associated symptoms lead to a devastating decrease in quality of life. The cannabinoids and their derivatives have emerged as an encouraging alternative due to their management of symptom in MS. Objective: The aim of the study was to investigate the mechanism of action of cannabidiol (CBD), a nonpsychoactive cannabinoid, on molecular and cellular events associated with leukocyte recruitment induced by experimental autoimmune encephalomyelitis (EAE). Materials and Methods: C57BL/6 female mice were randomly assigned to the four experimental groups: C (control group), CBD (cannabidiol-treated group, 5 mg/kg i.p.; 14 days), EAE (experimental autoimmune encephalomyelitis-induced group), and EAE+CBD (experimental autoimmune encephalomyelitis-induced plus cannabidiol-treated group). Results: The results indicated that 5 mg/kg of CBD injected intraperitoneally between the 1st and 14th days of EAE could reduce the leukocyte rolling and adhesion into the spinal cord microvasculature as well cellular tissue infiltration. These results were supported by a decreased mRNA expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in the spinal cord. Conclusion: Purified CBD reduces in vivo VCAM and ICAM-mediated leukocyte recruitment to the spinal cord microvasculature at EAE peak disease.

Development of an in vitro peptide-stimulated T cell assay to evaluate immune effects by cannabinoid compounds

Previous studies demonstrated that cannabinoids exhibit immunosuppressive effects in experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis (MS). To ask questions about treatment timing and investigate mechanisms for immune suppression by the plant-derived cannabinoids, cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC), an in vitro peptide stimulation of naive splenocytes (SPLC) was developed to mimic T cell activation in EAE. The peptide was derived from the myelin oligodendrocyte glycoprotein (MOG) protein, which is one component of the myelin sheath. MOG peptide is typically used with an immune adjuvant to trigger MOG-reactive T cells that attack MOG-containing tissues, causing demyelination and clinical disease in EAE. To develop the in vitro model, naïve SPLC were stimulated with MOG peptide on day 0 and restimulated on day 4. Cytokine analyses revealed that CBD and THC suppressed MOG peptide-stimulated cytokine production. Flow cytometric analysis showed that intracellular cytokines could be detected in CD4+ and CD8+ T cells. To determine if intracellular calcium was altered in the cultures, cells were stimulated for 4 days to assess the state of the cells at the time of MOG peptide restimulation. Both cannabinoid-treated cultures had a smaller population of the calcium-positive population as compared to vehicle-treated cells. These results demonstrate the establishment of an in vitro model that can be used to mimic MOG-reactive T cell stimulation in vivo.

Unveiling the Potential of Cannabinoids in Multiple Sclerosis and the Dawn of Nano-Cannabinoid Medicine

Multiple sclerosis is the predominant autoimmune disorder affecting the central nervous system in adolescents and adults. Specific treatments are categorized as disease-modifying, whereas others are symptomatic treatments to alleviate painful symptoms. Currently, no singular conventional therapy is universally effective for all patients across all stages of the illness. Nevertheless, cannabinoids exhibit significant promise in their capacity for neuroprotection, anti-inflammation, and immunosuppression. This review will examine the traditional treatment for multiple sclerosis, the increasing interest in using cannabis as a treatment method, its role in protecting the nervous system and regulating the immune system, commercially available therapeutic cannabinoids, and the emerging use of cannabis in nanomedicine. In conclusion, cannabinoids exhibit potential as a disease-modifying treatment rather than merely symptomatic relief. However, further research is necessary to unveil their role and establish the safety and advancements in nano-cannabinoid medicine, offering the potential for reduced toxicity and fewer adverse effects, thereby maximizing the benefits of cannabinoids.

The longitudinal effects of cannabidiol on brain temperature in patients with treatment-resistant epilepsy

Neuroinflammation (NI) is a key pathophysiological contributor to treatment-resistant epilepsy (TRE) that remains challenging to observe in vivo. Magnetic resonance spectroscopic imaging and thermometry (MRSI-t) is an emerging technique that can be used to non-invasively map brain temperature, whereby brain temperature elevations serve as a surrogate for the cellular and biochemical processes associated with NI. In a previous multimodal imaging study of focal epilepsy patients, we observed MRSI-t-based brain temperature elevations ipsilateral to the seizure onset zone (SOZ) that were concordant with evidence of edema (Sharma et al., 2023). Despite its potential as tool, it is unclear if MRSI-t can monitor changes in brain temperature in response to treatment. We imaged 25 participants approximately 12-weeks apart. Eight patients with TRE were imaged before receiving highly-purified pharmaceutical grade cannabidiol (CBD; pre-CBD) and after 12-weeks of CBD (on-CBD) therapy. Seventeen healthy controls (HCs) were also imaged twice. Repeated measures t-tests computed changes in TRE patients' seizure symptoms, mood, and brain temperature within their respective SOZs. Repeated measures ANOVAs tested Group*Time changes in imaging data. Participants with TRE had abnormally high peak brain temperatures within their SOZs that decreased after CBD initiation (p < 0.0001). Seizure severity scores also improved after CBD initiation (p < 0.001). These findings provide insights into the possible neural effects of CBD, and further demonstrate MRSI-t's potential as a tool for delineating SOZ. Further investigations into MRSI-t as a longitudinal measure of therapy-induced changes in NI are warranted.

An Overview of Cannabidiol as a Multifunctional Drug: Pharmacokinetics and Cellular Effects

Cannabidiol (CBD), a non-psychoactive compound derived from Cannabis Sativa, has garnered increasing attention for its diverse therapeutic potential. This comprehensive review delves into the complex pharmacokinetics of CBD, including factors such as bioavailability, distribution, safety profile, and dosage recommendations, which contribute to the compound's pharmacological profile. CBD's role as a pharmacological inhibitor is explored, encompassing interactions with the endocannabinoid system and ion channels. The compound's anti-inflammatory effects, influencing the Interferon-beta and NF-κB, position it as a versatile candidate for immune system regulation and interventions in inflammatory processes. The historical context of Cannabis Sativa's use for recreational and medicinal purposes adds depth to the discussion, emphasizing CBD's emergence as a pivotal phytocannabinoid. As research continues, CBD's integration into clinical practice holds promise for revolutionizing treatment approaches and enhancing patient outcomes. The evolution in CBD research encourages ongoing exploration, offering the prospect of unlocking new therapeutic utility.

Delimiting MOGAD as a disease entity using translational imaging

The first formal consensus diagnostic criteria for myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) were recently proposed. Yet, the distinction of MOGAD-defining characteristics from characteristics of its important differential diagnoses such as multiple sclerosis (MS) and aquaporin-4 antibody seropositive neuromyelitis optica spectrum disorder (NMOSD) is still obstructed. In preclinical research, MOG antibody-based animal models were used for decades to derive knowledge about MS. In clinical research, people with MOGAD have been combined into cohorts with other diagnoses. Thus, it remains unclear to which extent the generated knowledge is specifically applicable to MOGAD. Translational research can contribute to identifying MOGAD characteristic features by establishing imaging methods and outcome parameters on proven pathophysiological grounds. This article reviews suitable animal models for translational MOGAD research and the current state and prospect of translational imaging in MOGAD.

Cannabinoids in neuroinflammatory disorders: Focusing on multiple sclerosis, Parkinsons, and Alzheimers diseases

The medicinal properties of cannabis and cannabinoid-derivative are entirely investigated and known. In addition, the identification of psychotropic plant cannabinoids has led to more studies regarding the cannabinoid system and its therapeutic features in the treatment and management of clinical symptoms of neuroinflammatory disorders, such as multiple sclerosis (MS), Parkinsons disease (PD), and Alzheimers disease (AD). In fact, cannabinoid agonists are able to control and regulate inflammatory responses. In contrast to the cannabinoid receptor type 1 (CB1) and its unwanted adverse effects, the cannabinoid receptor type 2 (CB2) and its ligands hold promise for new and effective therapeutic approaches. So far, some successes have been achieved in this field. This review will discuss an outline of the endocannabinoid system's involvement in neuroinflammatory disorders. Moreover, the pharmacological efficacy of different natural and synthetic preparations of phytocannabinoids acting on cannabinoid receptors, particularly in MS, PD, and AD, will be updated. Also, the reasons for targeting CB2 for neurodegeneration will be explained.

Advances and Challenges of Cannabidiol as an Anti-Seizure Strategy: Preclinical Evidence

The use of Cannabis for medicinal purposes has been documented since ancient times, where one of its principal cannabinoids extracted from Cannabis sativa, cannabidiol (CBD), has emerged over the last few years as a promising molecule with anti-seizure potential. Here, we present an overview of recent literature pointing out CBD's pharmacological profile (solubility, metabolism, drug-drug interactions, etc.,), CBD's interactions with multiple molecular targets as well as advances in preclinical research concerning its anti-seizure effect on both acute seizure models and chronic models of epilepsy. We also highlight the recent attention that has been given to other natural cannabinoids and to synthetic derivatives of CBD as possible compounds with therapeutic anti-seizure potential. All the scientific research reviewed here encourages to continue to investigate the probable therapeutic efficacy of CBD and its related compounds not only in epilepsy but also and specially in drug-resistant epilepsy, since there is a dire need for new and effective drugs to treat this disease.

Cannabinoids as Immune System Modulators: Cannabidiol Potential Therapeutic Approaches and Limitations

Introduction: Cannabidiol (CBD) is the second most abundant Phytocannabinoid in Cannabis extracts. CBD has a binding affinity for several cannabinoid and cannabinoid-associated receptors. Epidiolex (oral CBD solution) has been lately licensed by the Food and Drug Administration (FDA) for the treatment of pediatric epileptic seizures. Methods: In this review, we discussed the most promising applications of CBD for chronic inflammatory conditions, namely CBD's anti-inflammatory effects during inflammatory bowel disease, coronavirus disease (antiviral effect), brain pathologies (neuroprotective and anti-inflammatory properties), as well as CBD immunomodulatory and antitumoral activities in the tumor microenvironment. Special focus was shed on the main therapeutic mechanisms of action of CBD, particularly in the control of the immune system and the endocannabinoid system. Results: Findings suggest that CBD is a potent immunomodulatory drug as it has manifested immunosuppressive properties in the context of sterile inflammation (e.g., inflammatory bowel disease, rheumatoid arthritis, and neurodegenerative diseases), and immunoprotective effects during viral infections (e.g. COVID-19) Similarly, CBD has exhibited a selective response toward cancer types by engaging different targets and signaling pathways. These results are in favor of the primary function of the endocannabinoid system which is homeostatic maintenance. Conclusion: The presented evidence suggests that the endocannabinoid system is a prominent target for the treatment of inflammatory and autoimmune diseases, rheumatoid diseases, viral infections, neurological and psychological pathologies, and cancer. Moreover, the antitumoral activities of CBD have been suggested to be potentially used in combination with chemo- or immunotherapy during cancer. However, clinical results are still lacking, which raises a challenge to apply translational cannabis research to the human immune system.

Endocannabinoid Modulation in Neurodegenerative Diseases: In Pursuit of Certainty

Simple Summary

Neurodegenerative diseases represent an important cause of morbidity and mortality worldwide. Existing therapeutic options are limited and focus mostly on improving symptoms and reducing exacerbations. The endocannabinoid system is involved in the pathophysiology of such disorders, an idea which has been highlighted by recent scientific work. The current work focusses its attention on the importance and implications of this system and its synthetic and natural ligands in disorders such as Alzheimer’s, Parkinson’s, Huntington’s and multiple sclerosis.

Abstract

Neurodegenerative diseases are an increasing cause of global morbidity and mortality. They occur in the central nervous system (CNS) and lead to functional and mental impairment due to loss of neurons. Recent evidence highlights the link between neurodegenerative and inflammatory diseases of the CNS. These are typically associated with several neurological disorders. These diseases have fundamental differences regarding their underlying physiology and clinical manifestations, although there are aspects that overlap. The endocannabinoid system (ECS) is comprised of receptors (type-1 (CB1R) and type-2 (CB2R) cannabinoid-receptors, as well as transient receptor potential vanilloid 1 (TRPV1)), endogenous ligands and enzymes that synthesize and degrade endocannabinoids (ECBs). Recent studies revealed the involvement of the ECS in different pathological aspects of these neurodegenerative disorders. The present review will explore the roles of cannabinoid receptors (CBRs) and pharmacological agents that modulate CBRs or ECS activity with reference to Alzheimer’s Disease (AD), Parkinson’s Disease (PD), Huntington’s Disease (HD) and multiple sclerosis (MS).

Neurological Benefits, Clinical Challenges, and Neuropathologic Promise of Medical Marijuana: A Systematic Review of Cannabinoid Effects in Multiple Sclerosis and Experimental Models of Demyelination

Despite current therapeutic strategies for immunomodulation and relief of symptoms in multiple sclerosis (MS), remyelination falls short due to dynamic neuropathologic deterioration and relapses, leading to accrual of disability and associated patient dissatisfaction. The potential of cannabinoids includes add-on immunosuppressive, analgesic, neuroprotective, and remyelinative effects. This study evaluates the efficacy of medical marijuana in MS and its experimental animal models. A systematic review was conducted by a literature search through PubMed, ProQuest, and EBSCO electronic databases for studies reported since 2007 on the use of cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) in MS and in experimental autoimmune encephalomyelitis (EAE), Theiler’s murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD), and toxin-induced demyelination models. Study selection and data extraction were performed by 3 reviewers, and 28 studies were selected for inclusion. The certainty of evidence was appraised using the Cochrane GRADE approach. In clinical studies, there was low- and moderate-quality evidence that treatment with ~1:1 CBD/THC mixtures as a nabiximols (Sativex®) oromucosal spray reduced numerical rating scale (NRS) scores for spasticity, pain, and sleep disturbance, diminished bladder overactivity, and decreased proinflammatory cytokine and transcription factor expression levels. Preclinical studies demonstrated decreases in disease severity, hindlimb stiffness, motor function, neuroinflammation, and demyelination. Other experimental systems showed the capacity of cannabinoids to promote remyelination in vitro and by electron microscopy. Modest short-term benefits were realized in MS responders to adjunctive therapy with CBD/THC mixtures. Future studies are recommended to investigate the cellular and molecular mechanisms of cannabinoid effects on MS lesions and to evaluate whether medical marijuana can accelerate remyelination and retard the accrual of disability over the long term.

Cannabidiol modulation of oxidative stress and signalling

Cannabidiol (CBD), one of the primary non-euphoric components in the Cannabis sativa L. plant, has undergone clinical development over the last number of years as a therapeutic for patients with Lennox-Gastaut syndrome and Dravet syndromes. This phytocannabinoid demonstrates functional and pharmacological diversity, and research data indicate that CBD is a comparable antioxidant to common antioxidants. This review gathers the latest knowledge regarding the impact of CBD on oxidative signalling, with focus on the proclivity of CBD to regulate antioxidants and control the production of reactive oxygen species. CBD is considered an attractive therapeutic agent for neuroimmune disorders, and a body of literature indicates that CBD can regulate redox function at multiple levels, with a range of downstream effects on cells and tissues. However, pro-oxidant capacity of CBD has also been reported, and hence caution must be applied when considering CBD from a therapeutic standpoint. Such pro- and antioxidant functions of CBD may be cell- and model-dependent and may also be influenced by CBD dose, the duration of CBD treatment and the underlying pathology.

Δ9 -Tetrahydrocannabinol promotes functional remyelination in the mouse brain

BACKGROUND AND PURPOSE

Research on demyelinating disorders aims to find novel molecules that are able to induce oligodendrocyte precursor cell differentiation to promote central nervous system remyelination and functional recovery. Δ⁹ -Tetrahydrocannabinol (THC), the most prominent active constituent of the hemp plant Cannabis sativa, confers neuroprotection in animal models of demyelination. However, the possible effect of THC on myelin repair has never been studied.

EXPERIMENTAL APPROACH

By using oligodendroglia-specific reporter mouse lines in combination with two models of toxin-induced demyelination, we analysed the effect of THC on the processes of oligodendrocyte regeneration and functional remyelination.

KEY RESULTS

We show that THC administration enhanced oligodendrocyte regeneration, white matter remyelination and motor function recovery. THC also promoted axonal remyelination in organotypic cerebellar cultures. THC remyelinating action relied on the induction of oligodendrocyte precursor differentiation upon cell cycle exit and via CB₁ cannabinoid receptor activation.

CONCLUSIONS AND IMPLICATIONS

Overall, our study identifies THC administration as a promising pharmacological strategy aimed to promote functional CNS remyelination in demyelinating disorders.

Immunomodulatory Potential of Cannabidiol in Multiple Sclerosis: a Systematic Review

Multiple sclerosis (MS) is the most common chronic autoimmune disease of the central nervous system. Efficacy of treatments for MS is associated with risk of adverse effects, and effective and well-tolerated drugs remain a major unmet need. Cannabis (Cannabis sativa L., fam. Cannabaceae) and cannabinoids are popular among MS patients to treat spasticity and pain. Cannabinoids are endowed with remarkable immunomodulating properties, and in particular the non-psychotropic cannabinoid cannabidiol (CBD) is increasingly recognized as anti-inflammatory and immunosuppressive, nevertheless with excellent tolerability even at high doses. In this systematic review, we retrieved and critically evaluated available evidence regarding the immune and disease-modifying effects of CBD in experimental autoimmune encephalomyelitis (EAE) and in MS. Evidence in rodent models of EAE strongly supports CBD as effective, while clinical evidence is still limited and usually negative, due to paucity of studies and possibly to the use of suboptimal dosing regimens. Better characterization of targets acted upon by CBD in MS should be obtained in ex vivo/in vitro studies in human immune cells, and higher doses should be tested in well-designed clinical trials with clinically relevant efficacy endpoints. Graphical Abstract.

Therapeutic Prospects of Cannabinoids in the Immunomodulation of Prevalent Autoimmune Diseases

Introduction: Cannabinoids such as ▵-9-THC and CBD can downregulate the immune response by modulating the endocannabinoid system. This modulation is relevant for the treatment of prevalent autoimmune diseases (ADs), such as multiple sclerosis (MS), systemic lupus erythematosus (SLE), diabetes mellitus type 1 (DMT1), and rheumatoid arthritis (RA). These conditions require new therapeutic options with fewer side effects for the control of the autoimmune response. Objective: to conduct a literature review of preclinical scientific evidence that supports further clinical investigations for the use of cannabinoids (natural or synthetic) as potential immunomodulators of the immune response in ADs. Methodology: A systematic search was carried out in different databases using different MeSH terms, such as Cannabis sativa L., cannabinoids, immunomodulation, and ADs. Initially, 677 journal articles were found. After filtering by publication date (from 2000 to 2020 for SLE, DMT1, and RA; and 2010 to 2020 for MS) and removing the duplicate items, 200 articles were selected and analyzed by title and summary associated with the use of cannabinoids as immunomodulatory treatment for those diseases. Results: Evidence of the immunomodulatory effect of cannabinoids in the diseases previously mentioned, but SLE that did not meet the search criteria, was summarized from 24 journal articles. CBD was found to be one of the main modulators of the immune response. This molecule decreased the number of Th1 and Th17 proinflammatory cells and the production of the proinflammatory cytokines, interleukin (IL)-1, IL-12, IL-17, interferon (IFN)-γ, and tumor necrosis factor alpha, in mouse models of MS and DMT1. Additionally, new synthetic cannabinoid-like molecules, with agonist or antagonist activity on CB1, CB2, TRPV1, PPAR-α, and PPAR-γ receptors, have shown anti-inflammatory properties in MS, DMT1, and RA. Conclusion: Data from experimental animal models of AD showed that natural and synthetic cannabinoids downregulate inflammatory responses mediated by immune cells responsible for AD chronicity and progression. Although synthetic cannabinoid-like molecules were evaluated in just two clinical trials, they corroborated the potential use of cannabinoids to treat some ADs. Notwithstanding, new cannabinoid-based approaches are required to provide alternative treatments to patients affected by the large group of ADs.

Molecular Targets of Cannabidiol in Experimental Models of Neurological Disease

Cannabidiol (CBD) is a non-psychoactive phytocannabinoid known for its beneficial effects including antioxidant and anti-inflammatory properties. Moreover, CBD is a compound with antidepressant, anxiolytic, anticonvulsant and antipsychotic effects. Thanks to all these properties, the interest of the scientific community for it has grown. Indeed, CBD is a great candidate for the management of neurological diseases. The purpose of our review is to summarize the in vitro and in vivo studies published in the last 15 years that describe the biochemical and molecular mechanisms underlying the effects of CBD and its therapeutic application in neurological diseases. CBD exerts its neuroprotective effects through three G protein coupled-receptors (adenosine receptor subtype 2A, serotonin receptor subtype 1A and G protein-coupled receptor 55), one ligand-gated ion channel (transient receptor potential vanilloid channel-1) and one nuclear factor (peroxisome proliferator-activated receptor γ). Moreover, the therapeutical properties of CBD are also due to GABAergic modulation. In conclusion, CBD, through multi-target mechanisms, represents a valid therapeutic tool for the management of epilepsy, Alzheimer’s disease, multiple sclerosis and Parkinson’s disease.

A Simple, Fast, and Green Oil Sample Preparation Method for Determination of Cannabidioloic Acid and Cannabidiol by HPLC-DAD

Currently, the medical use of food supplements containing Cannabis sativa has attracted the interest of consumers, as well as the medical and scientific community. With the increasing consumption of these products, there is also a risk of their abuse or discrepancy between the actual and declared contents of active substances by the manufacturer in these products. Thus, the development and elaboration of analytical procedures for determination of appropriate phytocannabinoids seems to be important. This work focuses on the development of a simple, fast and environmentally friendly liquid-liquid extraction method combined with fat freezing from an oil sample to isolate two phytocannabinoids: cannabidiol (CBD) and cannabidiolic acid (CBDA). The extraction method was optimized considering efficacy and repeatability of extraction, as well as minimalizing use of organic reagents and sample amount. Under the optimized conditions, extraction recovery for CBD was 97.3–109% and for CBDA was 69.1–69.5% with precision (RSD, %) 5.0–8.4 and 7.1–10.6, respectively. The evaluated main analytical parameters of the developed high pressure liquid chromatography with diode array detector (HPLC-DAD) method for both studied cannabinoids are satisfactory. The usability of the developed method was checked by analysis of real samples of a food supplement–hemp oil enriched with CBD.

A Critical Review of the Role of the Cannabinoid Compounds Δ9-Tetrahydrocannabinol (Δ9-THC) and Cannabidiol (CBD) and their Combination in Multiple Sclerosis Treatment

Many people with MS (pwMS) use unregulated cannabis or cannabis products to treat the symptoms associated with the disease. In line with this, Sativex, a synthetic combination of cannabidiol (CBD) and Δ⁹-tetrahydrocannabinol (Δ⁹-THC) has been approved to treat symptoms of spasticity. In animals, CBD is effective in reducing the amounts of T-cell infiltrates in the spinal cord, suggesting CBD has anti-inflammatory properties. By doing this, CBD has shown to delay symptom onset in animal models of multiple sclerosis and slow disease progression. Importantly, combinations of CBD and Δ⁹-THC appear more effective in treating animal models of multiple sclerosis. While CBD reduces the amounts of cell infiltrates in the spinal cord, Δ⁹-THC reduces scores of spasticity. In human studies, the results are less encouraging and conflict with the findings in animals. Drugs which deliver a combination of Δ⁹-THC and CBD in a 1:1 ratio appear to be only moderately effective in reducing spasticity scores, but appear to be almost as effective as current front-line treatments and cause less severe side effects than other treatments, such as baclofen (a GABA-B receptor agonist) and tizanidine (an α2 adrenergic receptor agonist). The findings of the studies reviewed suggest that cannabinoids may help treat neuropathic pain in pwMS as an add-on therapy to already established pain treatments. It is important to note that treatment with cannabinoid compounds may cause significant cognitive dysfunction. Long term double-blind placebo studies are greatly needed to further our understanding of the role of cannabinoids in multiple sclerosis treatment.

Amifostine ameliorates induction of experimental autoimmune encephalomyelitis: Effect on reactive oxygen species/NLRP3 pathway

Multiple sclerosis (MS) is an autoimmune disease for which conventional treatments have limited efficacy or side effects. Free radicals are primarily involved in blood-brain barrier disruption and induce neuronal and axonal damage, thus promoting the development of MS. Amifostine, a radioprotective drug used as a cytoprotective agent, attenuates oxidative stress and improves radiation damage by acting as a direct scavenger of reactive oxygen and nitrogen species. The aim of this study was to evaluate the effects of amifostine on MS in a mouse model of experimental autoimmune encephalomyelitis (EAE), which was developed by immunizing C57BL/6 mice with myelin oligodendrocyte glycoprotein and pertussis toxin. EAE mice received intraperitoneal injections of amifostine prior to onset of clinical symptoms and were monitored up to day 15 post induction. We observed abnormal clinical behavioral scores and a decrease in body weight. Histological analysis showed severe inflammatory infiltration and demyelination in the brain and spinal cord lumbar enlargements where significant upregulation of the mRNA expression of the pro-inflammatory cytokines interleukin-6 and interleukin-8, downregulation of the anti-inflammatory cytokine interleukin-10, and obvious microgliosis were also observed. Amifostine treatment potently reversed these abnormal changes. The anti-inflammatory effect of amifostine was associated with the inhibition of reactive oxygen species generation. Furthermore, the expression of proteins involved in the NLRP3 signaling pathway and pyroptosis was decreased. In conclusion, our study showed that amifostine ameliorates induction of experimental autoimmune encephalomyelitis via anti-inflammatory and anti-pyroptosis effects, providing further insights into the use of amifostine for the treatment of MS.

Immune Responses Regulated by Cannabidiol

Introduction: Cannabidiol (CBD) as Epidiolex^® (GW Pharmaceuticals) was recently approved by the U.S. Food and Drug Administration (FDA) to treat rare forms of epilepsy in patients 2 years of age and older. Together with the increased societal acceptance of recreational cannabis and CBD oil for putative medical use in many states, the exposure to CBD is increasing, even though all of its biological effects are not understood. Once such example is the ability of CBD to be anti-inflammatory and immune suppressive, so the purpose of this review is to summarize effects and mechanisms of CBD in the immune system. It includes a consideration of reports identifying receptors through which CBD acts, since the “CBD receptor,” if a single one exists, has not been definitively identified for the myriad immune system effects. The review then provides a summary of in vivo and in vitro effects in the immune system, in autoimmune models, with a focus on experimental autoimmune encephalomyelitis, and ends with identification of knowledge gaps.

Conclusion: Overall, the data overwhelmingly support the notion that CBD is immune suppressive and that the mechanisms involve direct suppression of activation of various immune cell types, induction of apoptosis, and promotion of regulatory cells, which, in turn, control other immune cell targets.

NFKF is a synthetic fragment derived from rat hemopressin that protects mice from neurodegeneration

Previous studies suggested the pharmacological potential of rat hemopressin (PVNFKFLSH) and its shorter synthetic peptide NFKF, to protect from pilocarpine-induced seizures in mice. Orally administered NFKF was shown to be hundred times more potent than cannabidiol in delaying the first seizure induced by pilocarpine in mice. Here, using an experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis we have shown that C57BL/6 J mice orally administrated with NFKF (500 μg/kg) presented better EAE clinical scores and improved locomotor activity compared to saline administrated control mice. NFKF blocked the production of IL-1beta and IL-6, and has high scores binding cannabinoid type 2 receptors. Therefore, NFKF is an exciting new possibility to neurodegenerative diseases therapeutics.

Use of Cannabidiol in the Treatment of Epilepsy: Efficacy and Security in Clinical Trials

Cannabidiol (CBD) is one of the cannabinoids with non-psychotropic action, extracted from Cannabis sativa. CBD is a terpenophenol and it has received a great scientific interest thanks to its medical applications. This compound showed efficacy as anti-seizure, antipsychotic, neuroprotective, antidepressant and anxiolytic. The neuroprotective activity appears linked to its excellent anti-inflammatory and antioxidant properties. The purpose of this paper is to evaluate the use of CBD, in addition to common anti-epileptic drugs, in the severe treatment-resistant epilepsy through an overview of recent literature and clinical trials aimed to study the effects of the CBD treatment in different forms of epilepsy. The results of scientific studies obtained so far the use of CBD in clinical applications could represent hope for patients who are resistant to all conventional anti-epileptic drugs.

Case Report: Clinical Outcome and Image Response of Two Patients With Secondary High-Grade Glioma Treated With Chemoradiation, PCV, and Cannabidiol

We describe two patients with a confirmed diagnosis of high-grade gliomas (grades III/IV), both presenting with O6-methylguanine-DNA methyltransferase (MGMT) methylated and isocitrate dehydrogenase (IDH-1) mutated who, after subtotal resection, were submitted to chemoradiation and followed by PCV, a multiple drug regimen (procarbazine, lomustine, and vincristine) associated with cannabidiol (CBD). Both patients presented with satisfactory clinical and imaging responses at periodic evaluations. Immediately after chemoradiation therapy, one of the patients presented with an exacerbated and precocious pseudoprogression (PSD) assessed by magnetic resonance imaging (MRI), which was resolved in a short period. The other patient presented with a marked remission of altered areas compared with the post-operative scans as assessed by MRI. Such aspects are not commonly observed in patients only treated with conventional modalities. This observation might highlight the potential effect of CBD to increase PSD or improve chemoradiation responses that impact survival. Further investigation with more patients and critical molecular analyses should be performed.

Cannabidiol induced apoptosis in human monocytes through mitochondrial permeability transition pore-mediated ROS production

Cannabidiol (CBD) has been reported to induce apoptosis in immune cells through oxidative stress-related mechanisms. The objective of the present study was to investigate the cellular mechanisms for CBD-induced apoptosis and oxidative stress in human monocytes. Exposure of freshly isolated human monocytes to CBD induced apoptosis in a time- and concentration-dependent manner. Time-course analyses revealed the induction of intracellular reactive oxygen species (ROS) at 1-2 h post CBD (16 μM) exposure. By comparison, the CBD treatment rapidly elicited the depolarization of mitochondrial membrane potential (MMP) within 5 min, and the oxidation of cardiolipin, a major lipid component of the mitochondrial inner membrane, within 15 min. Moreover, CBD induced the release of cytochrome c (Cyt c) from mitochondria. Mechanistic studies revealed that CBD-induced ROS production and apoptosis were not associated with the alteration of mitochondrial superoxide dismutase activity, the electron leakage through mitochondrial respiratory chain, and Fe²⁺- and Ca²⁺-mediated mechanisms. In contrast, CBD-induced apoptosis and MMP depolarization were markedly attenuated by the mitochondrial permeability transition pore (MPTP) inhibitor cyclosporin A (CsA), but not the calcineurin inhibitor FK506. Furthermore, CsA prevented cardiolipin oxidation and the MPTP opening induced by CBD. The present study suggests that CBD acts on the mitochondria to elicit ROS generation and apoptosis through MPTP opening and provides critical insights into the cellular mechanisms for CBD-induced oxidative stress in apoptotic monocytes.

Cannabidiol Attenuates Experimental Autoimmune Encephalomyelitis Model of Multiple Sclerosis Through Induction of Myeloid-Derived Suppressor Cells

Multiple sclerosis (MS) is a chronic debilitating autoimmune disease without a cure. While the use of marijuana cannabinoids for MS has recently been approved in some countries, the precise mechanism of action leading to attenuate neuroinflammation is not clear. We used experimental autoimmune encephalomyelitis (EAE), a murine model of MS, to explore the anti-inflammatory properties of cannabidiol (CBD), a non-psychoactive cannabinoid. Treatment with CBD caused attenuation of EAE disease paradigms as indicated by a significant reduction in clinical scores of paralysis, decreased T cell infiltration in the central nervous system, and reduced levels of IL-17 and IFNγ. Interestingly, CBD treatment led to a profound increase in myeloid-derived suppressor cells (MDSCs) in EAE mice when compared to the vehicle-treated EAE controls. These MDSCs caused robust inhibition of MOG-induced proliferation of T cells in vitro. Moreover, adoptive transfer of CBD-induced MDSCs ameliorated EAE while MDSC depletion reversed the beneficial effects of CBD treatment, thereby conclusively demonstrating that MDSCs played a crucial role in CBD-mediated attenuation of EAE. Together, these studies demonstrate for the first time that CBD treatment may ameliorate EAE through induction of immunosuppressive MDSCs.

Evaluation of Marijuana Compounds on Neuroimmune Endpoints in Experimental Autoimmune Encephalomyelitis

Cannabinoid compounds refer to a group of more than 60 plant-derived compounds in Cannabis sativa, more commonly known as marijuana. Exposure to marijuana and cannabinoid compounds has been increasing due to increased societal acceptance for both recreational and possible medical use. Cannabinoid compounds suppress immune function, and while this could compromise one's ability to fight infections, immune suppression is the desired effect for therapies for autoimmune diseases. It is critical, therefore, to understand the effects and mechanisms by which cannabinoid compounds alter immune function, especially immune responses induced in autoimmune disease. Therefore, this unit will describe induction and assessment of the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis (MS), and its potential alteration by cannabinoid compounds. The unit includes three approaches to induce EAE, two of which provide correlations to two forms of MS, and the third specifically addresses the role of autoreactive T cells in EAE. © 2018 by John Wiley & Sons, Inc.