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Cannabinoids control spasticity and tremor in a MS model

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Abstract

Chronic relapsing experimental allergic encephalomyelitis (CREAE) is an autoimmune model of multiple sclerosis. Although both these diseases are typified by relapsing-remitting paralytic episodes, after CREAE induction by sensitization to myelin antigens Biozzi ABH mice also develop spasticity and tremor. These symptoms also occur during multiple sclerosis and are difficult to control. This has prompted some patients to find alternative medicines, and to perceive benefit from cannabis use. Although this benefit has been backed up by small clinical studies, mainly with non-quantifiable outcomes, the value of cannabis use in multiple sclerosis remains anecdotal. Here we show that cannabinoid (CB) receptor agonism using R(+)-WIN 55,212, delta9-tetrahydrocannabinol, methanandamide and JWH-133 (ref. 8) quantitatively ameliorated both tremor and spasticity in diseased mice. The exacerbation of these signs after antagonism of the CB1 and CB2 receptors, notably the CB1 receptor, using SR141716A and SR144528 (ref. 8) indicate that the endogenous cannabinoid system may be tonically active in the control of tremor and spasticity. This provides a rationale for patients' indications of the therapeutic potential of cannabis in the control of the symptoms of multiple sclerosis, and provides a means of evaluating more selective cannabinoids in the future.

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... Studies utilizing explant or organotypic culture systems have been proved useful in determining whether cannabinoids/endocannabinoids can reduce excitotoxicity in ex vivo models of epileptic activity. CBD attenuated kainite mediated CA3 injury in rat organotypic hippocampal slice cultures (OHSCs) Leweke et al., 2007;Webb et al., 2008;Montgomery et al., 2016;Cui et al., 2017;Campbell et al., 20212-Arachidonoylglycerol 2-AG CB1, CB2 Cabral et al., 2008Hohmann et al., 2019;Campbell et al., 2021 N- Webb et al., 2008;Duncan et al., 2009;Garg et al., 2010;Hohmann et al., 2019;Im, 2021 Howlett et al., 1984;Hampson et al., 1998;Baker et al., 2000;van der Stelt et al., 2001;Kozela et al., 2013;Aguado et al., 2021;Landucci et al., 2021;Lana et al., 2022 Cannabidiol CBD CB2, GPR55, PPARγ, TRPV2, 5HTA1, direct antioxidant Hampson et al., 1998;Jones et al., 2010;Ruiz-Valdepeñas et al., 2011;Kozela et al., 2013;Sun et al., 2017;da Silva et al., 2018;Hohmann et al., 2019;Bouskila et al., 2021;Landucci et al., 2021Landucci et al., , 2022Lana et al., 2022;Patel et al., 2022 Levonantradol (CP 50,556- Nagayama et al., 1999;Baker, et al., 2000;Bilsland et al., 2006;Solbrig et al., 2010 ...
... Studies utilizing explant or organotypic culture systems have been proved useful in determining whether cannabinoids/endocannabinoids can reduce excitotoxicity in ex vivo models of epileptic activity. CBD attenuated kainite mediated CA3 injury in rat organotypic hippocampal slice cultures (OHSCs) Leweke et al., 2007;Webb et al., 2008;Montgomery et al., 2016;Cui et al., 2017;Campbell et al., 20212-Arachidonoylglycerol 2-AG CB1, CB2 Cabral et al., 2008Hohmann et al., 2019;Campbell et al., 2021 N- Webb et al., 2008;Duncan et al., 2009;Garg et al., 2010;Hohmann et al., 2019;Im, 2021 Howlett et al., 1984;Hampson et al., 1998;Baker et al., 2000;van der Stelt et al., 2001;Kozela et al., 2013;Aguado et al., 2021;Landucci et al., 2021;Lana et al., 2022 Cannabidiol CBD CB2, GPR55, PPARγ, TRPV2, 5HTA1, direct antioxidant Hampson et al., 1998;Jones et al., 2010;Ruiz-Valdepeñas et al., 2011;Kozela et al., 2013;Sun et al., 2017;da Silva et al., 2018;Hohmann et al., 2019;Bouskila et al., 2021;Landucci et al., 2021Landucci et al., , 2022Lana et al., 2022;Patel et al., 2022 Levonantradol (CP 50,556- Nagayama et al., 1999;Baker, et al., 2000;Bilsland et al., 2006;Solbrig et al., 2010 ...
... THC remyelinating activity was dependent on the differentiation of oligodendrocyte precursor via CB1 (Aguado et al., 2021). In mouse models, cannabinoid receptor agonists reduce spasticity associated with multiple sclerosis (MS) (Baker, et al., 2000). THC administration can prevent the onset of a chronic relapsing experimental allergic encephalomyelitis model of MS in rodents. ...
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Cannabinoids are lipophilic substances derived from Cannabis sativa that can exert a variety of effects in the human body. They have been studied in cellular and animal models as well as in human clinical trials for their therapeutic benefits in several human diseases. Some of these include central nervous system (CNS) diseases and dysfunctions such as forms of epilepsy, multiple sclerosis, Parkinson’s disease, pain and neuropsychiatric disorders. In addition, the endogenously produced cannabinoid lipids, endocannabinoids, are critical for normal CNS function, and if controlled or modified, may represent an additional therapeutic avenue for CNS diseases. This review discusses in vitro cellular, ex vivo tissue and in vivo animal model studies on cannabinoids and their utility as therapeutics in multiple CNS pathologies. In addition, the review provides an overview on the use of cannabinoids in human clinical trials for a variety of CNS diseases. Cannabinoids and endocannabinoids hold promise for use as disease modifiers and therapeutic agents for the prevention or treatment of neurodegenerative diseases and neurological disorders.
... Regarding MS, there are two representative preclinical studies performed in Biozzi ABH mice. In the first study [97] several cannabinoids namely the Δ 9 -THC (10 mg/kg) was intravenously injected, WIN 55-212-2 (5 mg/kg), Dimethylbutyl-deoxy-Δ 8 -THC (JWH-133) (1.5 mg/ kg), and methanandamide (AEA analogue) (5 mg/kg) that were administered intraperitoneally. These cannabinoids were administered once, and the authors saw results in 10-30 min. ...
... These cannabinoids were administered once, and the authors saw results in 10-30 min. The administration of these compounds reduced tremor and spasticity which are associated to this pathology [97]. The authors suggested that the mechanism of action involves cannabinoid receptors because the use of specific antagonists of these receptors has led to higher tremor and spasticity when comparing to the effect observed in rats injected with an agonist and for rats that received an antagonist. ...
... The authors suggested that the mechanism of action involves cannabinoid receptors because the use of specific antagonists of these receptors has led to higher tremor and spasticity when comparing to the effect observed in rats injected with an agonist and for rats that received an antagonist. These in vivo results were more marked with CB1 receptor blocking [97]. In the second example CBD at a dose of 20 mg/ kg was injected once intraperitoneally in rats induced with MS and after this step the spasticity was measured. ...
Article
There has been an increased interest of the scientific community in cannabis and its constituents for therapeutic purposes. Although it is believed that cannabinoids can be effective for a few different conditions and syndromes, there are little objective data that clearly support the use of cannabis, cannabis extracts or even cannabidiol (CBD) oil. This review aims to explore the therapeutic potential of phytocannabinoids and synthetic cannabinoids for the treatment of several diseases. A broad search covering the past five years, was performed in PubMed and ClinicalTrial.gov databases, to identify papers focusing on the use of medical phytocannabinoids in terms of tolerability, efficacy and safety. Accordingly, there are preclinical data supporting the use of phytocannabinoids and synthetic cannabinoids for the management of neurological pathologies, acute and chronical pain, cancer, psychiatric disorders and chemotherapy-induced emetic symptoms. However, regarding the clinical trials, most of the collected data do not fully support the use of cannabinoids in the treatment of such conditions. Consequently, more studies are still needed to clarify ascertain if the use of these compounds is useful in the management of different pathologies.
... Experimental autoimmune encephalomyelitis (EAE) is an experimental autoimmune disease of the CNS that serves as an animal model for MS (Bjelobaba et al. 2018). For example, Baker et al. (2000), showed improvement in tremor and spasticity in EAE model mice when treated with plant cannabinoids, analogs, and CBRs agonists. By contrast, selective antagonists to these receptors inhibited clinical effects, indicating a possible involvement of the endocannabinoid system (Baker et al. 2000). ...
... For example, Baker et al. (2000), showed improvement in tremor and spasticity in EAE model mice when treated with plant cannabinoids, analogs, and CBRs agonists. By contrast, selective antagonists to these receptors inhibited clinical effects, indicating a possible involvement of the endocannabinoid system (Baker et al. 2000). In addition to treating symptoms, cannabinoids also contributed to neuronal protection through the CB 1 R and slowed down the neurodegenerative process (Pryce et al. 2003). ...
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Introduction: Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system characterized by neuroinflammation, demyelination and axonal loss. Cannabis, an immunomodulating agent, is known for its ability to treat MS effectively. However, due to variations in the profile of secondary metabolites, especially cannabinoids, among cannabis cultivars, the effectiveness of cannabis treatment can vary, with significant variability in the effects on different biological parameters. For screening available cultivars, cellular in vitro as well as pre-clinical in vivo assays, are required to evaluate the effectiveness of the wide range of chemical variability that exists in cannabis cultivars. This study evaluated comparatively three chemically diverse cannabis cultivars, CN2, CN4 and CN6, containing different ratios of phytocannabinoids, for their neuroinflammatory activity in MS model. Materials and methods: In vitro experiments were performed with lipopolysaccharide (LPS)-activated BV-2 microglia and primary glial cells to evaluate the effect of different cannabis cultivars on nitric oxide (NO) and inflammatory cytokines, as well as inducible nitric oxide synthase (iNOS) protein expression. An in vivo experiment using the experimental autoimmune encephalomyelitis (EAE) MS model was conducted using Myelin oligodendrocyte glycoprotein (MOG) as the activating peptide. The cannabis extracts of the cultivars CN2, CN4, CN6 or vehicle, were intraperitoneally injected with clinical scores given based on observed symptoms over the course of study. At the end of the experiment, the mice were sacrificed, and splenocyte cytokine secretion was measured using ELISA. Lumbar sections from the spinal cord of treated MS mice were evaluated for microglia, astrocytes and CD4+ cells. Results: Extracts of the CN2 cultivar contained tetrahydrocannabinolic acid (THCA) and tetrahydrocannabinol (THC) without cannabidiol (CBD), and a number of monoterpenes. CN4 contained cannabidiolic acid (CBDA) and tetrahydrocannabidiolic acid (THCA), with significant amounts of THC: CBD in a 1:1 ratio, as well as sesquiterpenes and some monoterpenes; and CN6 contained primarily CBDA and THCA, as well as THC and CBD in a 2:1 ratio, with some sesquiterpenes and no monoterpenes. All extracts were not cytotoxic in glial cells up to 50 µg/ml. Dose dependent inhibition of LPS-induced BV2 as well as primary microglial NO secretion confirmed the anti-inflammatory and anti-oxidative activity of the three cannabis cultivars. CN2 but not CN4 reduced both astrocytosis and microglial activation in lumbar sections of EAE mice. In contrast, CN4 but not CN2 significantly decreased the secretion of TNFα and Interferon γ (IFNγ) in primary splenocytes extracted from EAE mice. Conclusions: While both cannabis cultivars, CN2 and CN4, significantly reduced the severity of the clinical signs throughout the course of the study, they modulated different inflammatory mediators and pathways, probably due to differences in their phytocannabinoid composition. This demonstrates the differential potential of cannabis cultivars differing in chemotype to regulate neuroinflammation and their potential to treat MS.
... b, Intrathecal injection of a vehicle had no effect on harmaline-induced tremor. c, Area under the power spectra curve (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25). Each dot pair corresponds to one animal. ...
... e, Pretreatment with AM281 and subsequent intrathecal injection of a vehicle had no effect on tremor. f, Area under the power spectra curve (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25). Each dot pair corresponds to one animal. ...
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Cannabinoids reduce tremor associated with motor disorders induced by injuries and neurodegenerative disease. Here we show that this effect is mediated by cannabinoid receptors on astrocytes in the ventral horn of the spinal cord, where alternating limb movements are initiated. We first demonstrate that tremor is reduced in a mouse model of essential tremor after intrathecal injection of the cannabinoid analog WIN55,212-2. We investigate the underlying mechanism using electrophysiological recordings in spinal cord slices and show that endocannabinoids released from depolarized interneurons activate astrocytic cannabinoid receptors, causing an increase in intracellular Ca2+, subsequent release of purines and inhibition of excitatory neurotransmission. Finally, we show that the anti-tremor action of WIN55,212-2 in the spinal cords of mice is suppressed after knocking out CB1 receptors in astrocytes. Our data suggest that cannabinoids reduce tremor via their action on spinal astrocytes. Astrocytes regulate synaptic transmission. Carlsen et al. report that spinal astrocytes activated by endocannabinoids inhibit excitatory synaptic transmission and, thereby, decrease tremor.
... In this model, it was observed, in parallel with the entrance in the chronic phase, a profound neurodegeneration leading to hind-limb spasticity, elevated levels in the brain and spinal cord of AEA, its congener palmitoylethanolamide (3, PEA, Figure 3), and 2-AG, with respect to non-spastic EAE mice and healthy controls. [96,97,98,99,100] Interestingly, spasticity was rapidly increased after administration of a CB1R agonist, thus supporting the evidence that mitigation of hind limb spasticity is CB1R dependent and possibly derives from an endogenous compensatory mechanism mediated by the elevated ECs levels. [101,102] However, already three decades ago and even before EC description and categorization, the efficacy of Δ9-tetrahydrocannabinol (4, Δ9-THC, Figure 3), the psychoactive component of marijuana, to suppress EAE symptoms was reported [103] and, soon after, the efficacy of Δ8-THC (5, Figure 3), its less psychotropic analogue, was established in the same model. ...
... [101,102] However, already three decades ago and even before EC description and categorization, the efficacy of Δ9-tetrahydrocannabinol (4, Δ9-THC, Figure 3), the psychoactive component of marijuana, to suppress EAE symptoms was reported [103] and, soon after, the efficacy of Δ8-THC (5, Figure 3), its less psychotropic analogue, was established in the same model. [104] Later on, Baker and coworkers demonstrated that CBRs agonism using R-(+)-WIN 55,212 (6), Δ9-THC, methanandamide (7) and JWH-133 (8) (Figure 3) quantitatively ameliorated both tremor and spasticity in EAE mice thus providing a rationale for the therapeutic potential of cannabis in the control of the symptoms of MS. [105,96,106] The crucial role of ECs in neuroinflammation-derived neurodegeneration was also confirmed in CB1R-null mice, in which the rate of degeneration was increased with respect to wild-type EAE mice. In particular, these studies clearly indicate that the lack of CB1R is associated with an augmented caspase activation and with the loss of myelin proteins. ...
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Multiple sclerosis (MS) is a chronic, immune‐mediated disease of the central nervous system. At present, there is no definitive cure, and the few available disease‐modifying options display either poor efficacy or life‐threatening side effects. There is clear evidence that relapsing‐remitting clinical attacks in MS are driven by inflammatory demyelination and that the subsequent disease steps, being irresponsive to immunotherapy, result from neurodegeneration. The endocannabinoid system (ECS) stands halfway between three key pathomechanisms underlying MS, namely inflammation, neurodegeneration and oxidative stress, thus representing a kingpin for the identification of novel therapeutic targets in MS. This review summarizes the current state of the art in the field of endocannabinoid metabolism modulators and their in vivo effects on relevant animal models. We also highlight key molecular underpinnings of their therapeutic efficacy as well as the potential to turn them into promising clinical candidates.
... 16 Within Cannabis sativa, tetrahydrocannabinol (THC) is known for its muscle-relaxing, appetite-stimulating, and analgesic effects, while cannabidiol (CBD) is recognized for amplifying antispastic activity properties. [17][18][19] Recent research highlights the potential benefits of cannabidiol (CBD) in managing psoriasis through its immunomodulatory and anti-inflammatory effects. Studies indicate that CBD might play a role in lowering cytokine production and inflammatory responses within psoriatic cells, which could help alleviate the symptoms associated with the disease. ...
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Psoriasis is a chronic skin condition that can significantly impact the quality of life of those affected. As an autoimmune disease, it can lead to itchy, painful, and scaly patches on the skin. Although various treatments, including topical creams, phototherapy, and systemic medications, are currently available, they may not always offer effective relief and can have side effects. Researchers have thus been exploring the potential benefits of non-psychoactive compounds such as CBD, found in Cannabis sativa plants, for treating psoriasis. CBD treatment may reduce inflammation, oxidative stress, itching, abnormal proliferation of keratinocytes, and may increase hydration. This review aims to provide an overview of the existing literature on the potential uses of CBD for psoriasis treatment.
... However, addressing factors causing secondary fatigue can mitigate its severity (Farhadi et al., 2022;Ghabaae M et al., 2007;Gottberg et al., 2000;Hauser et al., 2008). Factors such as sleep disorders (Black et al., 2014;Côté et al., 2013;Iranzo et al., 2019;Taylor et al., 2007), reduced activity and excessive rest (Farhadi et al., 2022;Krupp et al., 1988;Mohr & Cox, 2001;Wood et al., 2013), psychological factors and depression (Mohr & Cox, 2001;Wood et al., 2013), and medications (Baker et al., 2000;Hauser et al., 2008;Schwartz et al., 1996) are considered potential contributors to secondary fatigue in these patients. ...
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Objective: The present study aimed to compare the effect of schema therapy and mindfulness technique on existential anxiety in individuals with multiple sclerosis. Methods and Materials: Based on its objective, the present study is of an applied type. The research design was quasi-experimental with a pre-test, post-test design with a control group. Participants were randomly assigned to two experimental groups and one control group. The statistical population of the study included all individuals with MS in Tehran. Using purposive sampling, individuals present in the MS Society were selected based on their pre-test scores on each variable and randomly assigned to three groups, including two experimental groups and one control group (15 individuals per group). The Good Existential Anxiety Scale was used to measure the research variables. Mindfulness training sessions were conducted according to Baer's (2006) protocol, and schema therapy was based on the proposed protocol by Young et al. (2003). The intervention was implemented over 8 consecutive weeks, with each session lasting 90 minutes. In the inferential statistics section, covariance analysis was used to examine the effectiveness of the therapeutic methods. Findings: The results indicated that the impact of schema therapy and mindfulness technique on dimensions of existential anxiety (e.g., purposelessness of tasks, worthlessness of life's meaning, inability to persuade others, disinterest in activities, and lack of responsibility towards others) was significant at the level of (p < 0.05). Conclusion: The results showed that there is a significant difference between the effectiveness of schema therapy and mindfulness technique in terms of their impact on existential anxiety in individuals with multiple sclerosis. The mindfulness technique was found to be more effective than schema therapy for individuals with multiple sclerosis.
... Cannabidiol (CBD) is a naturally occurring non-psychoactive cannabinoid compound that is found in the cannabis plant (Cannabis sativa L.). CBD was previously explored for various medical conditions and gained significant attention in recent years for its potential analgesic [127,128], anti-inflammatory [129][130][131], neuroprotective [132], anticonvulsant [129], antiemetic [133], and spasmolytic [134] properties. CBD emerged as a prospective candidate for the treatment of neuropathic pain due to its potential analgesic and anti-inflammatory effects [127][128][129][130][131]. CBD interacts with the endocannabinoid system (ECS) in the body, which plays a role in regulating various physiological processes, including pain perception [18,135,136]. ...
Article
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Neuropathic pain is a debilitating condition characterized by abnormal signaling within the nervous system, resulting in persistent and often intense sensations of pain. It can arise from various causes, including traumatic nerve injury, neuropathy, and certain diseases. We present an overview of current and emerging pharmacotherapies for neuropathic pain, focusing on novel drug targets and potential therapeutic agents. Current pharmacotherapies, including tricyclic antidepressants, gabapentinoids, and serotonin norepinephrine re-uptake inhibitors, are discussed, as are emerging treatments, such as ambroxol, cannabidiol, and N-acetyl-L-cysteine. Additionally, the article highlights the need for further research in this field to identify new targets and develop more effective and targeted therapies for neuropathic pain management.
... In addition to a favorable safety and tolerability profile in humans (Machado Bergamaschi et al., 2011), CBD has shown analgesic (Karst et al., 2003), neuroprotective (Patricio et al., 2020), anticonvulsant (Mccarberg and Barkin, 2007;Arumugam et al., 2011), antiemetic (Rock et al., 2012), antispasmodic (Baker et al., 2000) and anti-inflammatory properties (Mccarberg and Barkin, 2007;van den Elsen et al., 2014). Its neuroprotective effect is mainly associated with antioxidant and antiinflammatory action as well as the modulation of multiple brain biological targets. ...
Article
Nanotechnology has been widely used to improve stability, efficacy, release control and biopharmaceutical aspects of natural and synthetic cannabinoids. In this review, the main types of cannabinoid-based nanoparticles (NPs) reported so far are addressed, taking into account the advantages and disadvantages of each system. Formulation, preclinical and clinical studies performed with colloidal carriers were individually analyzed. Lipid-based nanocarriers have been recognized for their high biocompatibility and ability to improve both solubility and bioavailability. Δ9-tetrahydrocannabinol-loaded lipid systems designed to treat glaucoma, for example, showed superior in vivo efficacy in comparison to market formulations. The analyzed studies have shown that product performance can be modulated by varying particle size and composition. In the case of self-nano-emulsifying drug delivery systems, the reduced particle size shortens the time to reach high plasma concentrations while the incorporation of metabolism inhibitors extend the plasma circulation time. The use of long alkyl chain lipids in NP formulations, in turn, is strategized to achieve intestinal lymphatic absorption. Polymer NPs have been prioritized when a sustained or site-specific cannabinoid release is desirable (e.g., CNS-affecting diseases/cancer). The functionalization of the surface of polymer NPs makes their action even more selective whereas surface charge modulation is highlighted to provide mucoadhesion. The present study identified promising systems for targeted applications, making the process of optimizing new formulations more effective and faster. Although NPs have shown a promising role in the treatment of several difficult-to-treat diseases, more translational studies should be performed to confirm the benefits reported here.
... It has been reported that cannabinoid receptor agonists exert neuroprotective effects in mixed cortical cultures exposed to AMPA and NMDA, therefore reducing neuronal death Loría et al., 2010). Additionally, the CB1-mediated signaling is essential for tremor and spasticity control in animal model of chronic relapsing experimental autoimmune encephalomyelitis (CREAE) and EAE in CB1 knockout mice (Baker et al., 2000;Pryce and Baker, 2007). Besides, the dual activation of CB1 and CB2 by WIN 55,212-2, a cannabinoid agonist, improves the clinical score shown by animals, reduces inflammation and restores tolerance to selfmyelin antigen (Arevalo-Martin et al., 2012), while WOBE437, an inhibitor of eCB reuptake, reduces MS severity and infiltration of immune cells into the CNS (Reynoso-Moreno et al., 2021). ...
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Historically, Cannabis is one of the first plants to be domesticated and used in medicine, though only in the last years the amount of Cannabis-based products or medicines has increased worldwide. Previous preclinical studies and few published clinical trials have demonstrated the efficacy and safety of Cannabis-based medicines in humans. Indeed, Cannabis-related medicines are used to treat multiple pathological conditions, including neurodegenerative disorders. In clinical practice, Cannabis products have already been introduced to treatment regimens of Alzheimer’s disease, Parkinson’s disease and Multiple Sclerosis’s patients, and the mechanisms of action behind the reported improvement in the clinical outcome and disease progression are associated with their anti-inflammatory, immunosuppressive, antioxidant, and neuroprotective properties, due to the modulation of the endocannabinoid system. In this review, we describe the role played by the endocannabinoid system in the physiopathology of Alzheimer, Parkinson, and Multiple Sclerosis, mainly at the neuroimmunological level. We also discuss the evidence for the correlation between phytocannabinoids and their therapeutic effects in these disorders, thus describing the main clinical studies carried out so far on the therapeutic performance of Cannabis-based medicines.
... In addition, THC can act as an agonist of G-protein-coupled receptors (GPR55 and GPR18), the peroxisome proliferator-activated receptor (PPARγ), and transient receptor potential channels (TRPA1, TRPV2, TRPV3, and TRPV4), and as an antagonist of transient receptor potential channel TRPM8 and 5-HT3 receptor A, and can increase anandamide and adenosine levels [38,48]. Numerous studies have shown that CBD possesses analgesic [16,49], neuroprotective [40], anticonvulsant [11], antiemetic [50], spasmolytic [51], and anti-inflammatory [11,12,52] properties ( Figure 3). Unlike THC, CBD has a very low affinity for both CB1 and CB2 receptors, with K i of 4359 and 2860 nM, respectively [47]. ...
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Cannabis (Cannabis sativa L.) plants from the family Cannabidaceae have been used since ancient times, to produce fibers, oil, and for medicinal purposes. Psychoactive delta-9-tetrahydrocannabinol (THC) and nonpsychoactive cannabidiol (CBD) are the main pharmacologically active compounds of Cannabis sativa. These compounds have, for a long time, been under extensive investigation, and their potent antioxidant and inflammatory properties have been reported, although the detailed mechanisms of their actions have not been fully clarified. CB1 receptors are suggested to be responsible for the analgesic effect of THC, while CB2 receptors may account for its immunomodulatory properties. Unlike THC, CBD has a very low affinity for both CB1 and CB2 receptors, and behaves as their negative allosteric modulator. CBD activity, as a CB2 receptor inverse agonist, could be important for CBD anti-inflammatory properties. In this review, we discuss the chemical properties and bioavailability of THC and CBD, their main mechanisms of action, and their role in oxidative stress and inflammation.
... In a report done by Baker et al., mice suffering from chronic relapsing EAE were treated with ∆ 9 -THC, methanandamide (analogue of AEA), WIN 55,212-2 (agonist of both CB1R and CB2R) and JWH-133 (agonist of CBR type 2). The treatment reduced motor symptoms, including limb spasticity, tremor and paralysis [203]. It was hypothesized that it could control clinical EAE symptoms through inhibition of synaptic transmission [204]. ...
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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).
... Following THC treatment, some mouse models of MS showed improved spasticity and tremors [116]. In clinical trials of MS patients, THC exerted both decreased urinary incontinence and antispasticity effects [117]. Although THC has its therapeutical effects, it also has psychoactive properties; alternately, CBD is less toxic than THC to humans and has been recognised as a nonpsychoactive compound [115]. ...
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Synthetic Cannabinoids (CBs) are a novel class of psychoactive substances that have rapidly evolved around the world with the addition of diverse structural modifications to existing molecules which produce new structural analogues that can be associated with serious adverse health effects. Synthetic CBs represent the largest class of drugs detected by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) with a total of 207 substances identified from 2008 to October 2020, and 9 compounds being reported for the first time. Synthetic CBs are sprayed on natural harmless herbs with an aim to mimic the euphoric effect of Cannabis. They are sold under different brand names including Black mamba, spice, K2, Bombay Blue, etc. As these synthetic CBs act as full agonists at the CB receptors, they are much more potent than natural Cannabis and have been increasingly associated with acute to chronic intoxications and death. Due to their potential toxicity and abuse, the US government has listed some synthetic CBs under schedule 1 classification. The present review aims to provide a focused overview of the literature concerning the development of synthetic CBs, their abuse, and potential toxicological effects including renal toxicity, respiratory depression, hyperemesis syndrome, cardiovascular effects, and a range of effects on brain function.
... The JWH family of synthetic cannabinoids have also been shown to be effective agonists of the cannabinoid receptors. Indeed, evidence indicates that JWH-133, a selective CB 2 agonist [161], ameliorates spasticity in murine MS [162] and prevents microglial cell activation and inflammation following exposure to -amyloid [163]. Finally, ACEA is a well described synthetic CB 1 agonist and analogue of AEA [164]. ...
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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.
... Clinical studies assessing the therapeutic potential of cannabinoids and neurological disorders have been predominantly in epilepsy, MS and Parkinson's. In a human trial with MS patients, Δ 9 -THC ameliorated urinary incontinence, spasticity and tremors in MS, but no effect on disease progression was observed (Baker et al., 2000;Freeman et al., 2006;Zajicek et al., 2003). So far, CBD alone (Epidiolex, GW Pharmaceuticals, Cambridge, UK) and as a 1:1 formulation with Δ 9 -THC (Sativex, GW Pharmaceuticals, Cambridge, UK) are the only licenced cannabis-based medicines and are prescribed to treat Dravet syndrome and Lennox-Gastaut syndrome, both rare forms of childhood epilepsy. ...
Article
The blood brain barrier (BBB) is central to the neurovascular unit (NVU) where it creates a semi-permeable barrier between neuronal tissue and the vascular networks that feed the brain. In neurodegenerative conditions and ischaemic stroke, the BBB becomes compromised and as a result its permeability increases. This not only exacerbates neuronal damage at the site of injury but also causes unwanted extravasation of peripheral immune cells into the brain, fuelling the overactivation of the immune response. Endocannabinoids and phytocannabinoids have both displayed neuroprotective effects, attenuating damage in a range of models including Parkinson’s, Huntington’s, amyloid lateral sclerosis and ischaemic stroke. The current study aimed to investigate the neuroprotective properties of emerging phytocannabinoids; specifically focusing on the BBB and NVU in the context of ischaemic stroke pathophysiology. A four-cell blood brain barrier model was constructed consisting of; human brain microvascular endothelial cells (HBMECs), astrocytes, pericytes and neurons. Cells were cultured on collagen coated transwell inserts and permeability was assessed using transepithelial resistance (TEER). A systematic review was conducted to examine work on the neuroprotective properties of minor phytocannabinoids, aside from cannabidiol (CBD) and delta 9-tetrahydrocannabinol (Δ9-THC). Following on from this, in vitro experiments were conducted using minor phytocannabinoids with the most neuroprotective potential; cannabidivarin (CBDV), cannabigerol (CBG) and cannabidiolic acid (CBDA). Inserts or monocultures (four cell model and pericyte, HBMECs and neuronal monolayers) were subjected to either a 4 h oxygen-glucose deprivation (OGD) protocol or an 8 h OGD (astrocyte monocultures), to model ischaemic stroke in vitro. Media was analysed for various chemokines and cytokines using enzyme-linked immunoassays or multiplex assays. From the systematic review, emerging phytocannabinoids cannabidivarin (CBDV) and cannabigerol (CBG) were found to display efficacy in various neurogenerative conditions and of the limited available mechanistic data, were found to mediate some of their effects through peroxisome proliferator-activated receptor gamma (PPARy). Data showed CBDV (300 nM-10 µM) attenuated MCP-1 levels in HBMEC monolayers, as well as reducing IL-6 (30 nM, 1 µM and 10 µM; p<0.05) and VEGF (10 nM- 10 µM; p<0.01) levels in astrocyte monocultures post OGD. CBG (10 nM-3 µM; p<0.0001) also reduced levels of IL-6 secreted by astrocytes and decreased levels of DNA damage response proteins including Chk1, Chk2, H2A.X and p53 post OGD. Neither CBG, nor CBDV reduced levels of IL-6, VEG or IL-8 in pericytes compared to the vehicle control post OGD. Cannabidiolic acid (CBDA) was also investigated and was found to decrease IL-6 in pericyte monocultures which was mediated, at least in part, by 5-HT1A activation. In a four-cell model of the BBB, CBDA offset increases in permeability vs the vehicle control and offered direct protection to neurons, as shown by a lack of propidium iodide (PI) staining in CBDA treated cells, indicating live cells are present. Data presented in this thesis show minor phytocannabinoids CBDV, CBG and CBDA provide protection against OGD mediated damage, with CBDA also offering protection against increases in permeability of the BBB post OGD. These novel data warrant further investigation into the neuroprotective properties of phytocannabinoids, particularly in ischaemic stroke.
... This antihyperalgesia was abrogated by co-treatment with AM630, suggesting that CB2R activation on spinal dorsal horn neurons suppresses the hypersensitivity correlated with EAE. Baker et al. (2000) showed that JWH133 mitigated the tremors and spasticity in chronic relapsing EAE model mice. However, treatment with SR144528 exacerbated these symptoms, indicating that tonic CB2R activity may modulate tremor and spasticity. ...
Article
The pharmacological activation of cannabinoid type 2 receptors (CB2R) gained attention due to its ability to mitigate neuroinflammatory events without eliciting psychotropic activities, a limiting factor for the drugs targeting cannabinoid type 1 receptors (CB1R). Therefore, ligands activating CB2R are receiving enormous importance for therapeutic targeting in numerous diseases including neurodegenerative, neuropsychiatric and neurodevelopmental disorders as well as traumatic injuries and neuropathic pain where neuroinflammation is a common accompaniment. Since the characterization of CB2R, many CB2R selective synthetic ligands have been developed with high selectivity and functional activity. Among numerous ligands, JWH133 has been found one of the compounds with high selectivity for CB2R. JWH133 has been reported to exhibit numerous pharmacological activities including antioxidant, anti-inflammatory, anticancer, cardioprotective, hepatoprotective, gastroprotective, nephroprotective, and immunomodulatory. Recent studies have showed that JWH133 possesses potent neuroprotective properties in several neurological disorders, including neuropathic pain, anxiety, epilepsy depression, alcoholism, psychosis, stroke, and neurodegeneration. Additionally, JWH133 protects neurons from oxidative damage and inflammation, promotes neuronal survival and neurogenesis, and serves as an immunomodulatory agent. The present review comprehensively examined neuropharmacological activities of JWH133 in neurological disorders including neurodegenerative, neurodevelopmental and neuropsychiatric using synoptic tables and elucidated pharmacological mechanisms based on reported observations. Considering the available data, JWH133 appears to be a promising CB2R agonist molecule for further evaluation and it can be a prototype agent for a unique class of drugs in drug discovery and development for neurotherapeutics and neuroprotection. Further, regulatory toxicology and pharmacokinetic studies are required to determine safety and proceed for clinical evaluation.
... In patients who suffer from neuropathic pain, it could significantly reduce the intensity of chronic pain and also improve sleep. Cannabis also helps with involuntary muscle tightness and reduces muscle tremors and spasticity (Baker and others 2000;Borgelt and others 2013;Iannotti and others 2019;Pertwee 2008;Ware and others 2010;Wilsey and others 2013;Woodhams and others 2015). In addition to the plant-based phytocannabinoids, much effort has gone into studying the endogenous cannabinoids, 2-arachidonoyl glycerol (2-AG) and arachidonoyl ethanolamide (anandamide), which have important physiological implications (De Petrocellis and others 2011; Iannotti and others 2019). ...
Article
Full-text available
Voltage-gated sodium (Nav) channels initiate action potentials in excitable tissues. Altering these channels’ function can lead to many pathophysiological conditions. Nav channels are composed of several functional and structural domains that could be targeted pharmacologically as potential therapeutic means against various neurological conditions. Mutations in Nav channels have been suggested to underlie various clinical syndromes in different tissues and in association with conditions ranging from epileptic to muscular problems. Treating those mutations that increase the excitability of Nav channels requires inhibitors that could effectively reduce channel firing. The main non-psychotropic constituent of the cannabis plant, cannabidiol (CBD), has recently gained interest as a viable compound to treat some of the conditions that are associated with Nav malfunctions. In this review, we discuss an overview of Nav channels followed by an in-depth description of the interactions of CBD and Nav channels. We conclude with some clinical implications of CBD use against Nav hyperexcitability based on a series of preclinical studies published to date, with a focus on Nav/CBD interactions.
... Different studies in MS mouse models have shown positive effects following the activation of CBRs [14]. In murine Theiler's encephalitis virus-induced demyelinating disease (TMEV-IDD) and chronic relapsing autoimmune encephalomyelitis (CREAE), treatment with CBR agonists revealed a beneficial impact on inflammation, improving tremor and spasticity [39,40]. Immunohistochemical analysis in post-mortem brains of MS patients showed an upregulation of microglia CB2Rs and increased amounts of FAAH metabolites [41]. ...
Article
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Neurodegenerative disorders are a widespread cause of morbidity and mortality worldwide, characterized by neuroinflammation, oxidative stress and neuronal depletion. The broad-spectrum neuroprotective activity of the Mediterranean diet is widely documented, but it is not yet known whether its nutritional and caloric balance can induce a modulation of the endocannabinoid system. In recent decades, many studies have shown how endocannabinoid tone enhancement may be a promising new therapeutic strategy to counteract the main hallmarks of neurodegeneration. From a phylogenetic point of view, the human co-evolution between the endocannabinoid system and dietary habits could play a key role in the pro-homeostatic activity of the Mediterranean lifestyle: this adaptive balance among our ancestors has been compromised by the modern Western diet, resulting in a “clinical endocannabinoid deficiency syndrome”. This review aims to evaluate the evidence accumulated in the literature on the neuroprotective, immunomodulatory and antioxidant properties of the Mediterranean diet related to the modulation of the endocannabinoid system, suggesting new prospects for research and clinical interventions against neurodegenerative diseases in light of a nutraceutical paradigm.
... CBD, along with Δ9-tetrahydrocannabinol (THC), is a major phytocannabinoid and both are well described components of medicines. Unlike THC, CBD is not psychoactive and is now being used to treat epilepsy (O'Connell et al., 2017;Baker et al., 2000). A growing number of studies have demonstrated the anticancer properties of CBD, in both in vitro and in vivo models (Ramer and Hinz, 2017;Kis et al., 2019). ...
Article
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The cannabinoid, cannabidiol (CBD), is part of the plant's natural defense system that when given to animals has many useful medicinal properties, including activity against cancer cells, modulation of the immune system, and efficacy in epilepsy. Although there is no consensus on its precise mode of action as it affects many cellular targets, CBD does appear to influence mitochondrial function. This would suggest that there is a cross-kingdom ability to modulate stress resistance systems that enhance homeostasis. As NAD(P)H autofluorescence can be used as both a metabolic sensor and mitochondrial imaging modality, we assessed the potential of this technique to study the in vitro effects of CBD using 2-photon excitation and fluorescence lifetime imaging microscopy (2P-FLIM) of NAD(P)H against more traditional markers of mitochondrial morphology and cellular stress in MCF7 breast cancer cells. 2P-FLIM analysis revealed that the addition of CBD induced a dose-dependent decrease in bound NAD(P)H, with 20 µM treatments significantly decreased the contribution of bound NAD(P)H by 14.6% relative to the control (p < 0.001). CBD also increased mitochondrial concentrations of reactive oxygen species (ROS) (160 ± 53 vs. 97.6 ± 4.8%, 20 µM CBD vs. control, respectively, p < 0.001) and Ca 2+ (187 ± 78 vs. 105 ± 10%, 20 µM CBD vs. the control, respectively, p < 0.001); this was associated with a significantly decreased mitochondrial branch length and increased fission. These are all suggestive of mitochondrial stress. Our results support the use of NAD(P)H autofluorescence as an investigative tool and provide further evidence that CBD can modulate mitochondrial function and morphology in a dose-dependent manner, with clear evidence of it inducing oxidative stress at higher concentrations. This continues to support emerging data in the literature and may provide further insight into its overall mode of action, not only in cancer, but potentially its function in the plant and why it can act as a medicine.
... There is a need for new treatments for these conditions. Cannabinoids have long been used to alleviate muscular problems (Borgelt et al., 2013;Baker et al., 2000). In this study, we show that CBD reduces skeletal contraction in rat diaphragm muscle. ...
Article
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Cannabidiol (CBD) is the primary nonpsychotropic phytocannabinoid found in Cannabis sativa, which has been proposed to be therapeutic against many conditions, including muscle spasms. Among its putative targets are voltage-gated sodium channels (Navs), which have been implicated in many conditions. We investigated the effects of CBD on Nav1.4, the skeletal muscle Nav subtype. We explored direct effects, involving physical block of the Nav pore, as well as indirect effects, involving modulation of membrane elasticity that contributes to Nav inhibition. MD simulations revealed CBD’s localization inside the membrane and effects on bilayer properties. Nuclear magnetic resonance (NMR) confirmed these results, showing CBD localizing below membrane headgroups. To determine the functional implications of these findings, we used a gramicidin-based fluorescence assay to show that CBD alters membrane elasticity or thickness, which could alter Nav function through bilayer-mediated regulation. Site-directed mutagenesis in the vicinity of the Nav1.4 pore revealed that removing the local anesthetic binding site with F1586A reduces the block of INa by CBD. Altering the fenestrations in the bilayer-spanning domain with Nav1.4-WWWW blocked CBD access from the membrane into the Nav1.4 pore (as judged by MD). The stabilization of inactivation, however, persisted in WWWW, which we ascribe to CBD-induced changes in membrane elasticity. To investigate the potential therapeutic value of CBD against Nav1.4 channelopathies, we used a pathogenic Nav1.4 variant, P1158S, which causes myotonia and periodic paralysis. CBD reduces excitability in both wild-type and the P1158S variant. Our in vitro and in silico results suggest that CBD may have therapeutic value against Nav1.4 hyperexcitability.
... Embora os compostos do vegetal produzam efeitos sobre um determinado número de órgãos, dentre os quais estão incluídos o sistema imunológico e reprodutivo, os efeitos terapêuticos apurados estão relacionados ao sistema nervoso central. Esses efeitos, em seres humanos correspondem à: analgesia (Brooks, 2002), mudança de humor, atua aumentando o apetite em pessoas tratados com quimioterapia (pacientes portadores de HIV e câncer) (Mechoulam, 1973), atividades psicomotoras com alteração, na percepção, na cognição, na memória, no controle da espasticidade em pacientes esclerótico (Baker et al., 2000). ...
... WIN-55,212-2 was reported to reduce inflammatory infiltrates in spinal cord and also induced apoptosis of encephalitogenic Tcell populations, partially via the CB2R in EAE model [548]. However, CB1R-related therapies cannot be disregarded since the CB1R has also been reported to treat various symptoms of MS, such as spasticity [549,550]. Interestingly, CB1Rs expressed on neuronal cells, but not on T cells, were also shown to have a critical role in cannabinoid-mediated attenuation of EAE pathology [551]. ...
Article
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The identification of the human cannabinoid receptors and their roles in health and disease, has been one of the most significant biochemical and pharmacological advancements to have occurred in the past few decades. In spite of the major strides made in furthering endocannabinoid research, therapeutic exploitation of the endocannabinoid system has often been a challenging task. An impaired endocannabinoid tone often manifests as changes in expression and/or functions of type 1 and/or type 2 cannabinoid receptors. It becomes important to understand how alterations in cannabinoid receptor cellular signaling can lead to disruptions in major physiological and biological functions, as they are often associated with the pathogenesis of several neurological, cardiovascular, metabolic, and inflammatory diseases. This review focusses mostly on the pathophysiological roles of type 1 and type 2 cannabinoid receptors, and it attempts to integrate both cellular and physiological functions of the cannabinoid receptors. Apart from an updated review of pre-clinical and clinical studies, the adequacy/inadequacy of cannabinoid-based therapeutics in various pathological conditions is also highlighted. Finally, alternative strategies to modulate endocannabinoid tone, and future directions are also emphasized.
... Cannabis was tried to manage persistent symptoms of MS such as tremor and spasticity. The anti-tremor effect of cannabis could involve the cholinergic, GABAergic, serotonergic, betaadrenergic, and cannabinoid systems [59,60]. Cannabis seemed to be beneficial for spasticity in MS. ...
Article
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Tremor is an important and common symptom in patients with multiple sclerosis (MS). It constituted one of the three core features of MS triad described by Charcot in the last century. Tremor could have a drastic impact on patients' quality of life. This paper provides an overview of tremor in MS and future perspectives with a particular emphasis on its epidemiology (prevalence: 25-58%), clinical characteristics (i.e., large amplitude 2.5-7 Hz predominantly postural or intention tremor vs. exaggerated physiological tremor vs. pseudo-rhythmic activity arising from cerebellar dysfunction vs. psychogenic tremor), pathophysiological mechanisms (potential implication of cerebellum, cerebello-thalamo-cortical pathways, basal ganglia, and brainstem), assessment modalities (e.g., tremor rating scales, Stewart-Holmes maneuver, visual tracking, digitized spirography and accelerometric techniques, accelerometry-electromyography coupling), and therapeutic options (i.e., including pharmacological agents, botulinum toxin A injections; deep brain stimulation or thalamotomy reserved for severe, disabling, or pharmaco-resistant tremors). Some suggestions are provided to help overcome the unmet needs and guide future therapeutic and diagnostic studies in this complex disorder.
... According to our literature research, there is no standard measure in rodents -especially in mice. Reports of clinical signs of spasticity such as a flexed elbow and forepaw are rare (Baker et al., 2000). Despite the genetic model, i.e., the spastic mice, characterized by a reduced muscle growth compared to wild type mice (Ziv et al., 1984), there are no reports in mice that investigated muscle spasms or increased muscle tone using force measurements and electromyographic recordings, as it has been reported in the well-established spastic rat tail model (Bennett et al., 1999). ...
Article
Although spasticity is one of the most common causes of motor disability worldwide, its precise definition and pathophysiology remain elusive, which to date renders its experimental targeting tricky. At least in part, this difficulty is caused by heterogeneous phenotypes of spasticity-causing neurological disorders, all causing spasticity by involving upper motor neurons. The most common clinical symptoms are a series of rapid muscle contractions (clonus), an increased muscle tone (hypertonia), and augmented tendon reflex activity (hyperreflexia). This muscle overactivity is due to disturbed inhibition of spinal reflexes following upper motor neuron dysfunction. Despite a range of physical and pharmacological therapies ameliorating the symptoms, their targeted application remains difficult. Therefore, to date, spasticity impacts rehabilitative therapy, and no therapy exists that reverses the pathology completely. In contrast to the incidence and importance of spasticity, only very little pre-clinical work in animal models exists, and this research is focused on the cat or the rat spastic tail model to decipher altered reflexes and excitability of the motor neurons in the spinal cord. Meanwhile, the characterization of spasticity in clinically more relevant mouse models of neurological disorders, such as stroke, remains understudied. Here, we provide a brief introduction into the clinical knowledge and therapy of spasticity and an in-depth review of pre-clinical studies of spasticity in mice including the current experimental challenges for clinical translation.
... Cannabinoids have long been used to alleviate muscular problems 59,60 . In this study, we show CBD reduces skeletal contraction in rat diaphragm muscle. ...
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Cannabis sativa contains active constituents called phytocannabinoids. Some phytocannabinoids are psychotropic and others are not. The primary non-psychotropic phytocannabinoid is cannabidiol (CBD), which is proposed to be therapeutic against many conditions, including muscle spasms. Mechanisms have been proposed for the action of CBD on different systems, involving multiple targets, including the voltage-gated sodium channel (Nav) family, which are heavily implicated in many of the conditions CBD has been reported to relieve. In this study, we investigated the modulatory mechanism of CBD on Nav1.4. Based on previous results, we tested the hypothesis that CBD mechanism of action involves: 1) modulation of membrane elasticity, which indirectly contributes to Nav inhibition; and 2) physical block of the Nav pore. We first performed molecular dynamic (MD) simulations to visualize CBD effects and localization inside the membrane, and then performed NMR to verify the MD results, showing CBD localizes below membrane headgroups. Then, we performed a gramicidin-based fluorescence (GFA) assay that showed CBD alters membrane elasticity. Next, we used site-directed mutagenesis in (F1586A) and around (WWWW) the Nav1.4 pore. Removing the local anesthetic binding site with F1586A reduced CBD block of INa. Occluding the fenestrations with WWWW blocked CBD access from the membrane into the Nav1.4 pore. However, stabilization of inactivation, via CBD-induced changes in membrane elasticity persisted, in WWWW. To investigate the potential therapeutic value of CBD against some Nav1.4 channelopathies, we used a pathogenic variant of Nav1.4, P1158S, known to cause myotonia and periodic paralysis. We found CBD reduces excitability in both wild-type and the mixed myotonia/periodic paralysis variant. Our in-vitro/in-silico results suggest that CBD may have therapeutic value against myotonia. Because Nav1.4 is crucial to skeletal muscle contraction, we used rat diaphragm myography and found the presence of saturating levels of CBD reduces skeletal muscle contraction. SUMMARY We used multidisciplinary approaches to show the mechanism and pathway by which CBD inhibits the skeletal muscle, Nav1.4. Our results suggest CBD modulates membrane elasticity and directly interacts with Nav1.4 within its pore.
Article
Cannabis is one of the oldest and widely used substances in the world. Cannabinoids within the cannabis plant, known as phytocannabinoids, mediate cannabis' effects through interactions with the body's endogenous cannabinoid system. This endogenous system, the endocannabinoid system, has important roles in physical and mental health. These roles point to the potential to develop cannabinoids as therapeutic agents, while underscoring the risks related to interfering with the endogenous system during non-medical use. This scoping narrative review synthesizes the current evidence for both the therapeutic and adverse effects of the major (i.e., Δ9-tetrahydrocannabinol and cannabidiol) and lesser studied minor phytocannabinoids, from nonclinical to clinical research. We pay particular attention to the areas where evidence is well-established, including analgesic effects after acute exposures and neurocognitive risks after acute and chronic use. In addition, drug development considerations for cannabinoids as therapeutic agents within the United States are reviewed. The proposed clinical study design considerations encourage methodological standards for greater scientific rigor and reproducibility, ultimately, to extend our knowledge of the risks and benefits of cannabinoids for patients and providers. Significance Statement This work provides a review of prior research related to phytocannabinoids, including therapeutic potential and known risks in the context of drug development within the United States. We also provide study design considerations for future cannabinoid drug development.
Chapter
Multiple sclerosis (MS) is a chronic demyelinating disease of the central and peripheral nervous systems. The symptoms, such as vision problems, muscle weakness, pain, balance problems, and paralysis, are due to the uncontrolled or inappropriate neural transmission that gradually worsens as the disease progresses. During the early stage of the disease, patients may experience long symptom-free periods, and the periods are interrupted by flare-ups that last days to weeks. It has been indicated that Cannabis, delta-9-tetrahydrocannabinol (THC), nabiximols, and oral Cannabis extract (OCE) may diminish spasticity associated with MS [19]. Nabiximols is a mucosal spray containing delta-9-THC and cannabidiol (CBD) in the 1:1 ratio and has been developed for treating MS. The US FDA has approved nabiximols and has also been approved in several European countries, Canada, and New Zealand for treating spasticity associated with MS.
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The human endocannabinoid system regulates a myriad of physiological processes through a complex lipid signaling network involving cannabinoids and their respective receptors, cannabinoid receptor 1 (hCB1R) and cannabinoid receptor 2 (hCB2R). Anandamide (AEA) and cannabidiol (CBD) are classical examples of cannabinoids that elicit a variety of effects, both beneficial and detrimental, through these receptors. Mounting evidence suggested the presence of other potential cannabinoid targets that may be responsible for other observable effects. However, prior pharmacological studies on these cannabinoid compounds provided scant evidence of direct engagement to these proposed targets. Moreover, to the best of our knowledge, no chemoproteomic studies have been demonstrated on CBD. Here we showed that, by taking advantage of a recently developed ‘label‐free’ 2D‐TPP (2 Dimensional‐Thermal Protein Profiling) approach, we have identified several new putative targets of both AEA and CBD. Comparison of these interaction landscapes with those obtained from well‐established affinity‐based protein profiling (AfBPP) platforms has led to the discovery of both shared and unique protein targets. Subsequent target validation of selected proteins led us to conclude that this 2D‐TPP strategy complements well with AfBPP.
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Δ9-tetrahydrocannabinol (THC) and its sibling, cannabidiol (CBD), are produced by the same Cannabis plant and have similar chemical structures but differ dramatically in their mechanisms of action and effects on brain functions. Both THC and CBD exhibit promising therapeutic properties; however, impairments and increased incidence of mental health diseases are associated with acute and chronic THC use, respectively, and significant side effects are associated with chronic use of high-dose CBD. This review covers recent molecular and preclinical discoveries concerning the distinct mechanisms of action and bioactivities of THC and CBD and their impact on human behavior and diseases. These discoveries provide a foundation for the development of cannabinoid-based therapeutics for multiple devastating diseases and to assure their safe use in the growing legal market of Cannabis-based products.
Article
Introduction: : To investigate whether published systematic reviews of randomized controlled trials provide sufficient clarity to inform prescribing of cannabinoid products aimed for medicinal use, we examined their features and findings in two well-researched areas: chronic cancer/noncancer pain and multiple sclerosis (MS)-related symptoms. Areas covered: : Structured searches from January 2011 to 2 February 2021 identified 31 systematic reviews (with/without meta-analyses) that met the inclusion criteria. Support for the efficacy of cannabinoids was minimal in cancer pain, and somewhat stronger in noncancer (especially neuropathic) pain and MS spasticity. All systematic reviews and most meta-analyses grouped cannabinoid products together without appropriate consideration of their differential attributes (active constituent(s), concentration/strength, dosage forms, administration route), dosing regimens or treatment durations. Patient populations and efficacy outcome measures were inhomogeneous, particularly for studies in noncancer pain and MS. Separate results for specific cannabinoid formulations were rarely provided. Expert opinion: : The therapeutic effect of cannabinoids, as already demonstrated for some products, is not reflected clearly in the current range of systematic reviews and meta-analyses in chronic pain and MS. To truly inform evidence-based practice, future publications should aim to present results by individual product from well-conducted clinical trials using appropriate and homogeneous outcome measures in well-defined patient populations.
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Tremor is an involuntary, rhythmic movement disorder. Despite its prevalence, the underlying pathophysiology remains poorly understood and effective treatment options are limited. Animal models are essential in enhancing our understanding of the mechanisms of tremorogenesis and developing new therapeutic interventions. Although tremor is amenable to measurement by automated systems, visual observation is still the most prevalent method for recording tremor in animal studies. This review gives a brief summary of two behavioral methods that enable quantitative measurement of forelimb tremor (the press-while-licking task) and whole-body tremor (the force-plate actometer) in rodents. These methods utilize force transducer and computing technologies to generate high-resolution force-time waveforms for automated detection and characterization of tremor. The focus will be on the sensitive, precise, and quantitative measurement of tremors induced in rodents by low-dose pharmacological agents, brain lesion, physical training, and genetic mutations. The methods reviewed here provide new tools that can facilitate preclinical assessment of treatment strategies for tremor.
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Although μ-opioid peptide (MOP) receptor agonists are effective analgesics available in clinical settings, their serious adverse effects put limits on their use. The marked increase in abuse and misuse of prescription opioids for pain relief and opioid overdose mortality in the past decade has seriously impacted society. Therefore, safe analgesics that produce potent analgesic effects without causing MOP receptor-related adverse effects are needed. This review highlights the potential therapeutic targets for the treatment of opioid abuse and pain based on available evidence generated through preclinical studies and clinical trials. To ameliorate the abuse-related effects of opioids, orexin-1 receptor antagonists and mixed nociceptin/MOP partial agonists have shown promising results in translational aspects of animal models. There are several promising non-opioid targets for selectively inhibiting pain-related responses, including nerve growth factor inhibitors, voltage-gated sodium channel inhibitors, and cannabinoid- and nociceptin-related ligands. We have also discussed several emerging and novel targets. The current medications for opioid abuse are opioid receptor-based ligands. Although neurobiological studies in rodents have discovered several non-opioid targets, there is a translational gap between rodents and primates. Given that the neuroanatomical aspects underlying opioid abuse and pain are different between rodents and primates, it is pivotal to investigate the functional profiles of these non-opioid compounds compared to those of clinically used drugs in non-human primate models before initiating clinical trials. More pharmacological studies of the functional efficacy, selectivity, and tolerability of these newly discovered compounds in non-human primates will accelerate the development of effective medications for opioid abuse and pain.
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We performed a structural study followed by a theoretical analysis of the chemical descriptors and the biological activity of a series of 5-thiophen-2-yl pyrazole derivatives as potent and selective Cannabinoid-1...
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Nearly all FDA approved drugs and bioactive small molecules exert their effects by binding to and modulating proteins. Consequently, understanding how small molecules interact with proteins at an molecular level is a central challenge of modern chemical biology and drug development. Complementary to structure-guided approaches, chemoproteomics has emerged as a method capable of high-throughput identification of proteins covalently bound by small molecules. To profile noncovalent interactions, established chemoproteomic workflows typically incorporate photoreactive moieties into small molecule probes, which enable trapping of small molecule-protein interactions (SMPIs). This strategy, termed photoaffinity labelling (PAL), has been utilized to profile an array of small molecule interactions, including for drugs, lipids, metabolites, and cofactors. Herein we describe the discovery of photocrosslinking chemistries, including a comparison of the strengths and limitations of implementation of each chemotype in chemoproteomic workflows. In addition, we highlight key examples where photoaffinity labelling has enabled target deconvolution and interaction site mapping.
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Medical benefi ts of cannabis and related compounds is widely known. Discovery of psychotropic plant cannabinoid Δ9-tetrahydrocannabinol have urged researchers to study more about the cannabinoid system and related therapeutics in the fi eld of neurology and medicine. Where activation of cannabinoid receptor type 1 (CB1R) yielded in unwanted and serious side eff ects, discovery of cannabinoid receptor type 2 (CB2R) and its ligands gave a new hope. Till now there is limited success in this fi eld because of complex expanded endocannabinoid system comprising of receptors, ligands and enzymes. In this review we will update about the role of endocannabinoidome relevant to neurological disorders.
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In the last decades, cannabinoid receptor 2 (CB2R) has continued to receive attention as a key therapeutic target in neuroprotection. Indeed, several findings highlight the neuroprotective effects of CB2R through suppression of both neuronal excitability and reactive microglia. Additionally, CB2R seems to be a more promising target than cannabinoid receptor 1 (CB1R) thanks to the lack of central side effects, its lower expression levels in the central nervous system (CNS), and its inducibility, since its expression enhances quickly in the brain following pathological conditions. This review aims to provide a thorough overview of the main natural and synthetic selective CB2R modulators, their chemical classification and their potential therapeutic usefulness in neuroprotection, a crucial aspect for the treatment of neurodegenerative diseases.
Chapter
Multiple sclerosis (MS) can cause a range of disabling symptoms which may differ greatly from patient to patient and over the course of the disease. While numerous effective immunotherapies are available for MS patients, symptomatic treatment options are scarce. Randomized controlled trials examining symptomatic therapies are lacking and the current data basis is insufficient and inconsistent. This chapter will give an overview of potential pharmacological and nonpharmacological treatment strategies for the most common MS symptoms and present useful multimodal approaches for managing different symptoms in MS patients.
Chapter
Multiple sclerosis is an autoimmune disease with underlying inflammatory and neurodegenerative processes. Future biomarker research is needed to increase our understanding of the pathophysiologic substrates of the disease and thereby enable prediction of disease course and response to immunomodulatory and neuroprotective therapy strategies. Recently developed ultra-sensitive analytic techniques (single molecule array (Simoa)) enable the reliable detection of low levels of protein that are released from the central nervous system (CNS) into the peripheral blood. However, peripheral sources of markers measured with the Simoa technique have to be taken into account, when interpreting CNS-disorders. In this chapter, we provide a detailed overview of the Simoa technique and present emerging and established markers of inflammatory and neurodegenerative processes of multiple sclerosis. We particularly highlight Neurofilament light chain (NfL), a biomarker for neurodegenerative processes in various neurological disorders.
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It has been established that the endogenous cannabinoid (endocannabinoid) system plays key modulatory roles in a wide variety of pathological conditions. The endocannabinoid system comprises both cannabinoid receptors, their endogenous ligands including 2-arachidonoylglycerol (2-AG), N-arachidonylethanolamine (anandamide, AEA), and enzymes that regulate the synthesis and degradation of endogenous ligands which include diacylglycerol lipase alpha (DAGL-α), diacylglycerol lipase beta (DAGL-β), fatty acid amide hydrolase (FAAH), monoacylglycerol lipase (MAGL), α/β hydrolase domain 6 (ABHD6). As the endocannabinoid system exerts considerable involvement in the regulation of homeostasis and disease, much effort has been made towards understanding endocannabinoid-related mechanisms of action at cellular, physiological, and pathological levels as well as harnessing the various components of the endocannabinoid system to produce novel therapeutics. However, drug discovery efforts within the cannabinoid field have been slower than anticipated to reach satisfactory clinical endpoints and raises an important question into the validity of developing novel ligands that therapeutically target the endocannabinoid system. To answer this, we will first examine evidence that supports the existence of an endocannabinoid system role within inflammatory diseases, neurodegeneration, pain, substance use disorders, mood disorders, as well as metabolic diseases. Next, this review will discuss recent clinical studies, within the last 5 years, of cannabinoid compounds in context to these diseases. We will also address some of the challenges and considerations within the cannabinoid field that may be important in the advancement of therapeutics into the clinic.
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The endocannabinoid system (ECS) is a complex physiological network involved in creating homeostasis and maintaining human health. Studies of the last 40 years have shown that endocannabinoids (ECs), a group of bioactive lipids, together with their set of receptors, function as one of the most important physiologic systems in human body. ECs and cannabinoid receptors (CBRs) are found throughout the body: in the brain tissues, immune cells, and in the peripheral organs and tissues as well. In recent years, ECs have emerged as key modulators of affect, neurotransmitter release, immune function, and several other physiological functions. This modulatory homoeostatic system operates in the regulation of brain activity and states of physical health and disease. In several research studies and patents the ECS has been recognised with neuro-protective properties thus it might be a target in neurodegenerative diseases. Most immune cells express these bioactive lipids and their receptors, recent data also highlight the immunomodulatory effects of endocannabinoids. Interplay of immune and nervous system has been recognized in past, recent studies suggest that ECS function as a bridge between neuronal and immune system. In several ongoing clinical trial studies, the ECS has also been placed in the anti-cancer drugs spotlight. This review summarizes the literature of cannabinoid ligands and their biosynthesis, cannabinoid receptors and their distribution, and the signaling pathways initiated by the binding of cannabinoid ligands to cannabinoid receptors. Further, this review highlights the functional role of cannabinoids and ECS in blood cell development, neuroimmune interactions and associated disorders. Moreover, we highlight the current state of knowledge of cannabinoid ligands as the mediators of neuroimmune interactions, which can be therapeutically effective for neuro-immune disorders and several diseases associated with neuroinflammation.
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Background Essential tremor is the most prevalent movement disorder and is thought to be caused by abnormalities in the cerebellar system; however, its underlying neural mechanism is poorly understood. In this study, we found that mice lacking netrin-G2, a cell adhesion molecule which is expressed in neural circuits related to the cerebellar system, exhibited a microtremor resembling an essential tremor. However, it was difficult to quantify microtremors in netrin-G2 KO mice. New Method We developed a new tremor detector which can quantify the intensity and frequency of a tremor. Results Using this system, we were able to characterize both the microtremors in netrin-G2 KO mice and low-dose harmaline-induced tremors which, to date, had been difficult to detect. Alcohol and anti-tremor drugs, which are effective in decreasing the symptoms of essential tremor in patients, were examined in netrin-G2 KO mice. We found that some drugs lowered the tremor frequency, but had little effect on tremor intensity. Forced swim as a stress stimulus in netrin-G2 KO mice dramatically enhanced tremor symptoms. Comparison with Existing Methods The detection performance even for tremors induced by low-dose harmaline was similar to that in previous studies or more sensitive than the others. Conclusions Microtremors in netrin-G2 KO mice are reliably and quantitatively detected by our new tremor detection system. We found different effects of medicines and factors between human essential tremors and microtremors in netrin-G2 KO mice, suggesting that the causations, mechanisms, and symptoms of tremors vary and are heterogeneous, and the objective analyses are required.
Chapter
The emerging role of the endocannabinoid system (ECS) in the control of symptoms and disease progression in multiple sclerosis (MS) has been highlighted by recent studies. MS is a chronic, immune-mediated, and demyelinating disorder of the central nervous system with no cure so far. It is widely reported that cannabinoids might be used to control MS symptoms and that they also might exert neuroprotective effects and slow down disease progression. The aim of this chapter is to give an overview of the main endogenous and synthetic cannabinoids used for the symptomatic amelioration of MS and their beneficial outcomes, providing new possible perspectives for the treatment of this disease.
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Inspired by the medicinal properties of the plant Cannabis sativa and its principal component (−)- trans-Δ ⁹ -tetrahydrocannabinol (THC), researchers have developed a variety of compounds to modulate the endocannabinoid system in the human brain. Inhibitors of fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), which are the enzymes responsible for the inactivation of the endogenous cannabinoids anandamide and 2-arachidonoylglycerol, respectively, may exert therapeutic effects without inducing the adverse side effects associated with direct cannabinoid CB 1 receptor stimulation by THC. Here we review the FAAH and MAGL inhibitors that have reached clinical trials, discuss potential caveats, and provide an outlook on where the field is headed. Expected final online publication date for the Annual Review of Pharmacology and Toxicology, Volume 61 is January 8, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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The spectral density of fluctuations in the audio power of many musical selections and of English speech varies approximately as 1/f (f is the frequency) down to a frequency of 5 multiplied by 10** minus **4 Hz. This result implies that the audio-power fluctuations are correlated over all times in the same manner as ″1/f noise″ in electronic components. The frequency fluctuations of music also have a 1/f spectral density at frequencies down to the inverse of the length of the piece of music. The frequency fluctuations of English speech have a quite different behavior, with a single characteristic time of about 0. 1 s, the average length of a syllable. The observations on music suggest that 1/f noise is a good choice for stochastic composition. Compositions in which the frequency and duration of each note were determined by 1/f noise sources sounded pleasing. Those generated by white-noise sources sounded too random, while those generated by 1/f**2 noise sounded too correlated.
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The widely‐known claim of Voss and Clarke (1978) that much music is well modelled by “1/ƒ noise” is critically examined. Some new data are provided for classical music, yielding mainly negative conclusions. In the course of the investigation some of the problems of the statistical analysis of musical data are discussed.
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This paper introduces the use of magnetic field tomography (MFT), a noninvasive technique based on distributed source analysis of magnetoencephalography data, which makes possible the three-dimensional reconstruction of dynamic brain activity in humans. MFT has a temporal resolution better than 1 msec and a spatial accuracy of 2-5 mm at the cortical level, which deteriorates to 1-3 cm at depths of 6 cm or more. MFT is used here to visualize the origin of a spatiotemporally organized pattern of coherent 40-Hz electrical activity. This coherence, initially observed during auditory input, was proposed to be generated by recurrent corticothalamic oscillation. In support of this hypothesis, we illustrate well-defined 40-Hz coherence between cortical-subcortical sites with a time shift that is consistent with thalamocortical conduction times. Studies on Alzheimer patients indicate that, while a similar activity pattern is present, the cortical component is reduced in these subjects.
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The neural correlates of music perception were studied by measuring cerebral blood flow (CBF) changes with positron emission tomography (PET). Twelve volunteers were scanned using the bolus water method under four separate conditions: (1) listening to a sequence of noise bursts, (2) listening to unfamiliar tonal melodies, (3) comparing the pitch of the first two notes of the same set of melodies, and (4) comparing the pitch of the first and last notes of the melodies. The latter two conditions were designed to investigate short-term pitch retention under low or high memory load, respectively. Subtraction of the obtained PET images, superimposed on matched MRI scans, provides anatomical localization of CBF changes associated with specific cognitive functions. Listening to melodies, relative to acoustically matched noise sequences, resulted in CBF increases in the right superior temporal and right occipital cortices. Pitch judgments of the first two notes of each melody, relative to passive listening to the same stimuli, resulted in right frontal-lobe activation. Analysis of the high memory load condition relative to passive listening revealed the participation of a number of cortical and subcortical regions, notably in the right frontal and right temporal lobes, as well as in parietal and insular cortex. Both pitch judgment conditions also revealed CBF decreases within the left primary auditory cortex. We conclude that specialized neural systems in the right superior temporal cortex participate in perceptual analysis of melodies; pitch comparisons are effected via a neural network that includes right prefrontal cortex, but active retention of pitch involves the interaction of right temporal and frontal cortices.
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A series of experiments examined auditory contour formation, investigating listeners' sensitivities to a family of random fractals known as fractional Brownian noises. Experiments 1A and 1B looked at identification of contours when 3 different noises were portrayed using variations in the pitch, duration, or loudness of successive notes of a sequence. Listeners could categorize pitch and loudness encodings, but not duration mappings. Experiment 2 looked at the effect of simultaneous presentation of pitch and loudness information, finding that these dimensions combined additively to increase identification of the noise distributions. Experiment 3 looked at discrimination of pitch contours as a function of changing fractal dimension. Discrimination curves approximated an inverted U shape, a finding that is not understandable in terms of sensitivity to differences in fractal dimension per se, nor in terms of "tuned" perceptual sensitivity to statistical regularities of the environment.
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Averaged event-related potential (ERP) data recorded from the human scalp reveal electroencephalographic (EEG) activity that is reliably time-locked and phase-locked to experimental events. We report here the application of a method based on information theory that decomposes one or more ERPs recorded at multiple scalp sensors into a sum of components with fixed scalp distributions and sparsely activated, maximally independent time courses. Independent component analysis (ICA) decomposes ERP data into a number of components equal to the number of sensors. The derived components have distinct but not necessarily orthogonal scalp projections. Unlike dipole-fitting methods, the algorithm does not model the locations of their generators in the head. Unlike methods that remove second-order correlations, such as principal component analysis (PCA), ICA also minimizes higher-order dependencies. Applied to detected-and undetected-target ERPs from an auditory vigilance experiment, the algorithm derived ten components that decomposed each of the major response peaks into one or more ICA components with relatively simple scalp distributions. Three of these components were active only when the subject detected the targets, three other components only when the target went undetected, and one in both cases. Three additional components accounted for the steady-state brain response to a 39-Hz background click train. Major features of the decomposition proved robust across sessions and changes in sensor number and placement. This method of ERP analysis can be used to compare responses from multiple stimuli, task conditions, and subject states.
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Music processing ability was studied in 65 right-handed patients who had undergone unilateral temporal cortectomy for the relief of intractable epilepsy, and 24 matched normal controls. The ability to recognize changes in note intervals and to distinguish between different rhythms and metres was tested by presentation of sequences of simple musical phrases with variations in either pitch or temporal dimensions. The responses (right or wrong) enabled us to determine in which component of the music processing mechanism the patients had deficits and hence, knowing the positions of the surgical lesions, to identify their separate cerebral locations. The results showed that a right temporal cortectomy impaired the use of both contour and interval information in the discrimination of melodies and a left temporal cortectomy impaired only the use of interval information. Moreover, they underlined the importance of the superior temporal gyrus in melody processing. The excision of a part of the auditory areas (posterior part of the superior temporal gyrus) was found to be most detrimental for pitch and temporal variation processing. In the temporal dimension, we observed a dissociation between metre and rhythm and the critical involvement of the anterior part of the superior temporal gyrus in metric processing. This study highlights the relevance of dissociating musical abilities into their most significant cognitive components in order to identify their separate cerebral locations.
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We measured endogenous cannabinoid release in dorsal striatum of freely moving rats by microdialysis and gas chromatography/mass spectrometry. Neural activity stimulated the release of anandamide, but not of other endogenous cannabinoids such as 2-arachidonylglycerol. Moreover, anandamide release was increased eightfold over baseline after local administration of the D2-like (D2, D3, D4) dopamine receptor agonist quinpirole, a response that was prevented by the D2-like receptor antagonist raclopride. Administration of the D1-like (D1, D5) receptor agonist SKF38393 had no such effect. These results suggest that functional interactions between endocannabinoid and dopaminergic systems may contribute to striatal signaling. In agreement with this hypothesis, pretreatment with the cannabinoid antagonist SR141716A enhanced the stimulation of motor behavior elicited by systemic administration of quinpirole. The endocannabinoid system therefore may act as an inhibitory feedback mechanism countering dopamine-induced facilitation of motor activity.
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We show that, when music pieces are cast in the form of time series of pitch variations, the concepts and tools of dynamical systems theory can be applied to the analysis of temporal dynamics in music. (i) Phase space portraits are constructed from the time series wherefrom the dimensionality is evaluated as a measure of the global dynamics of each piece. (ii) Spectral analysis of the time series yields power spectra ( approximately f(-nu)) close to red noise (nu approximately 2) in the low frequency range. (iii) We define an information entropy which provides a measure of the local dynamics in the musical piece; the entropy can be interpreted as an evaluation of the degree of complexity in the music, but there is no evidence of an analytical relation between local and global dynamics. These findings are based on computations performed on eighty sequences sampled in the music literature from the 18th to the 20th century. (c) 1995 American Institute of Physics.
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Mammalian tissues contain at least two types of cannabinoid receptor, CB1 and CB2 , both coupled to G proteins. CB1 receptors are expressed mainly by neurones of the central and peripheral nervous system whereas CB2 receptors occur in certain non-neuronal tissues, particularly in immune cells. The existence of endogenous ligands for cannabinoid receptors has also been demonstrated. The discovery of this 'endogenous cannabinoid system' has been paralleled by a renewed interest in possible therapeutic applications of cannabinoids, for example in the management of pain and in the suppression of muscle spasticity/spasm associated with multiple sclerosis or spinal cord injury. It has also prompted the development of a range of novel cannabinoid receptor ligands, including several that show marked selectivity for CB1 or CB2 receptors. This review summarizes current knowledge about the in vitro pharmacological properties of important CB1 and CB2 receptor ligands. Particular attention is paid to the binding properties of these ligands, to the efficacies of cannabinoid receptor agonists, as determined using cyclic AMP or [35S]GTPγS binding assays, and to selected examples of how these pharmacological properties can be influenced by chemical structure. The in vitro pharmacological properties of ligands that can potently and selectively oppose the actions of CB1 or CB2 receptor agonists are also described. When administered by themselves, some of these ligands produce effects in certain tissue preparations that are opposite in direction to those produced by cannabinoid receptor agonists and the possibility that the ligands producing such 'inverse cannabimimetic effects' are inverse agonists rather than pure antagonists is discussed.
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The book examines applications of correlation and spectral analysis bridging the gap between the engineering measurements and theoretical results from analytical models. Basic principles of correlation and spectral density analysis based on calculus, Fourier series, and the complex variable theory; procedures for analyzing single input/output relationships; time delay and phase lag estimates; and identification of multiple propagation paths and velocities for dispersive and nondispersive media are presented. Finally, the analysis of multiple input/output applications of multiple and partial coherence functions is given along with the practical statistical error analysis formulas for computing spectral density functions, coherence functions, and frequency response functions.
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Since multiple sclerosis (MS) is believed to be an immune-mediated disease, it follows that its therapies should be directed towards modulating the immune system. Current MS treatments, which include the use of exogenous steroids that are immunosuppressive, do not meet therapeutic objectives. delta 9-Tetrahydrocannabinol (THC), an active component of marijuana, has been shown to be immunosuppressive. To test THC's ability to suppress an immune-mediated disease, experimental autoimmune encephalomyelitis (EAE), the laboratory model of MS, was used. Lewis rats and strain 13 guinea pigs were administered THC either before inoculation for EAE or treated with THC after injection. Control animals received placebo. The effect of dose, in addition to the timing of treatment, was also investigated. All animals treated with placebo developed severe clinical EAE 10-12 days post-injection (d.p.i.) and more than 98% died by 15 d.p.i. THC-treated animals had either no clinical signs or mild signs with delayed onset (13-15 d.p.i.) with survival greater than 95%. Examination of central nervous system tissue revealed a marked reduction of inflammation in the THC-treated animals. Therefore, as THC has been shown to inhibit both clinical and histologic EAE, it may prove to be a new and relatively innocuous agent for the treatment of immune-mediated diseases.
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Steady-state magnetic responses to clicks presented at rates between 10 and 70 Hz have been recorded in healthy humans. The responses were highest in amplitude around 40 Hz. This amplitude enhancement is satisfactorily explained by summation of responses evoked by single clicks. The field maps suggest activation of the auditory cortex at all stimulus frequencies. Similar responses were obtained with gated noise bursts and by pauses in a series of clicks. The mean "apparent latency," determined from the phase lag at rates 30-70 Hz, was 54 ms. The physiological relevance of this quantity is shown to be questionable.
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Marijuana is reported to decrease spasticity in patients with multiple sclerosis. This is a double blind, placebo controlled, crossover clinical trial of delta-9-THC in 13 subjects with clinical multiple sclerosis and spasticity. Subjects received escalating doses of THC in the range of 2.5-15 mg., five days of THC and five days of placebo in randomized order, divided by a two-day washout period. Subjective ratings of spasticity and side effects were completed and semiquantitative neurological examinations were performed. At doses greater than 7.5 mg there was significant improvement in patient ratings of spasticity compared to placebo. These positive findings in a treatment failure population suggest a role for THC in the treatment of spasticity in multiple sclerosis.
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Spasticity is a common neurologic condition in patients with multiple sclerosis, stroke, cerebral palsy or an injured spinal cord. Animal studies suggest that THC has an inhibitory effect on polysynaptic reflexes. Some spastic patients claim improvement after inhaling cannabis. We tested muscle tone, reflexes, strength and performed EMGs before and after double-blinded oral administration of either 10 or 5 mg THC or placebo. The blinded examiner correctly identified the trials in which the patients received THC in seven of nine cases. For the group, 10 mg THC significantly reduced spasticity by clinical measurement (P less than 0.01). Quadriceps EMG interference pattern was reduced in those four patients with primarily extensor spasticity. THC was administered to eight other patients with spasticity and other CNS lesions. Responses varied, but benefit was seen in three of three patients with "tonic spasms." No benefit was noted in patients with cerebellar disease.
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Based on one patient's enthusiastic report, eight patients with multiple sclerosis, seriously disabled with tremor and ataxia, were given oral tetrahydrocannabinol. Two demonstrated improved motor coordination.
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Electromyographic (EMG) studies were carried out with the genetically spastic mouse (spa, autosomal recessive), obtained from matings of B6C3a/a, spa/+ heterozygotes. Spastic homozygotes exhibited high amplitude repetitive EMG bursts during spontaneous activity. Following an electrical stimulus to hindlimb or forelimb, high amplitude stereotyped EMG bursts were recorded from contralateral limbs in spastic mice, but were not observed in phenotypically unaffected littermates or normal C57BL/6J mice. The timing and latency of this stereotyped response to an electrical stimulus was consistent with the participation of spinal cord neuronal pathways. In normal C57BL/6J mice the administration of strychnine (0.65 mg/kg), but not picrotoxinin (up to convulsant doses), reproduced all of the behavioral and EMG features observed in spastic homozygotes. We hypothesize that the symptoms in the spastic mutant may result from a deficiency of strychnine-sensitive (presumably glycinergic) inhibition in the spinal cord.
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Transient and steady-state auditory evoked fields (AEFs) to brief tone pips were recorded over the left hemisphere at 7 different stimulus rates (0.125-39 Hz) using a 37-channel biomagnetometer. Previous observations of transient auditory gamma band response (GBR) activity were replicated. Similar rate characteristics and equivalent dipole locations supported the suggestion that the steady-state response (SSR) at about 40 Hz represents the summation of successive overlapping (10 Hz) middle latency responses (MLRs). On the other hand, differences in equivalent dipole locations and habituation effects suggest that the magnetically recorded GBR is a separate phenomenon which occurs primarily at low stimulus rates and is unrelated to either the magnetically recorded MRL or SSR.
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Steady-state responses (SSRs) or steady-state fields (SSFs) show maximum amplitude when tone pulses are presented at repetition rates near 40 Hz. This result has led to the hypothesis that the SSR/SSF consists of superimposed transient 'middle latency' responses which display wave periods near 40 Hz and summate with one another when phase locked by 40 Hz steady-state stimulation. We evaluated this hypothesis by comparing the cortical sources of the 40 Hz auditory SSF with sources of the middle latency Pa wave which is prominent in electrical and magnetic recordings, and with the cortical sources of the familiar N1 wave, at different carrier frequencies between 250 and 4000 Hz. SSF sources determined for the different carrier frequencies were found to display a 'medial' tendency tonotopy resembling that of the N1m (sources for the higher frequencies represented more deeply within the supratemporal sulcus), opposite the 'lateral' tendency tonotopy of the middle latency Pam (sources for the higher frequencies situated more laterally). A medial SSF tonotopy was observed in each of the subjects investigated, including three subjects for whom Pam and N1m maps were also available. These findings suggest that the 40 Hz SSF may not consist of summated or entrained middle latency responses, as has previously been proposed. Alternative mechanisms for the SSR are discussed.
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Fifty-three UK and 59 USA people with multiple sclerosis (MS) answered anonymously the first questionnaire on cannabis use and MS. From 97 to 30% of the subjects reported cannabis improved (in descending rank order): spasticity, chronic pain of extremities, acute paroxysmal phenomenon, tremor, emotional dysfunction, anorexia/weight loss, fatigue states, double vision, sexual dysfunction, bowel and bladder dysfunctions, vision dimness, dysfunctions of walking and balance, and memory loss. The MS subjects surveyed have specific therapeutic reasons for smoking cannabis. The survey findings will aid in the design of a clinical trial of cannabis or cannabinoid administration to MS patients or to other patients with similar signs or symptoms.
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There are at least two types of cannabinoid receptors, CB1 and CB2, both coupled to G-proteins. CB1 receptors are present in the central nervous system and CB1 and CB2 receptors in certain peripheral tissues. The existence of endogenous cannabinoid receptor agonists has also been demonstrated. These discoveries have led to the development of selective cannabinoid CB1 and CB2 receptor ligands. This review focuses on the classification, binding properties, effector systems and distribution of cannabinoid receptors. It also describes the various cannabinoid receptor agonists and antagonists now available and considers the main in vivo and in vitro bioassay methods that are generally used.
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The effects of R(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl]pyrrolo[1,2,3-de]-1,4- benzoxazin-yl]-(1-napthalenyl)methanone mesylate (WIN 55,212-2) and N-piperidino-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-3-pyrazo le-carboxamide (SR141716A) on guanosine-5'-O-(3-[35S]thio)triphosphate ([35S]GTPgammaS) binding to membranes isolated from human cannabinoid CB1 receptor-transfected Chinese hamster ovary (CHO) cells were examined. WIN 55,212-2 stimulated [35S]GTPgammaS binding 76.3% above basal levels whereas SR141716A produced a 22.3% decrease in basal [35S]GTPgammaS binding. These findings demonstrate that WIN 55,212-2 is an agonist and SR141716A is an inverse agonist in this system.
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To explore the relationship between the processing of melodic and rhythmic patterns in speech and music, we tested the prosodic and musical discrimination abilities of two "amusic" subjects who suffered from music perception deficits secondary to bilateral brain damage. Prosodic discrimination was assessed with sentence pairs where members of a pair differed by intonation or rhythm, and musical discrimination was tested using musical-phrase pairs derived from the prosody of the sentence pairs. This novel technique was chosen to make task demands as comparable as possible across domains. One amusic subject showed good performance on both linguistic and musical discrimination tasks, while the other had difficulty with both tasks. In both subjects, level of performance was statistically similar across domains, suggesting shared neural resource for prosody and music. Further tests suggested that prosody and music may overlap in the processes used to maintain auditory patterns in working memory.
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The potent analgesic effects of cannabis-like drugs and the presence of CB1-type cannabinoid receptors in pain-processing areas of the brain and spinal cord indicate that endogenous cannabinoids such as anandamide may contribute to the control of pain transmission within the central nervous system (CNS). Here we show that anandamide attenuates the pain behaviour produced by chemical damage to cutaneous tissue by interacting with CB1-like cannabinoid receptors located outside the CNS. Palmitylethanolamide (PEA), which is released together with anandamide from a common phospholipid precursor, exerts a similar effect by activating peripheral CB2-like receptors. When administered together, the two compounds act synergistically, reducing pain responses 100-fold more potently than does each compound alone. Gas-chromatography/mass-spectrometry measurements indicate that the levels of anandamide and PEA in the skin are enough to cause a tonic activation of local cannabinoid receptors. In agreement with this possibility, the CB1 antagonist SR141716A and the CB2 antagonist SR144528 prolong and enhance the pain behaviour produced by tissue damage. These results indicate that peripheral CB1-like and CB2-like receptors participate in the intrinsic control of pain initiation and that locally generated anandamide and PEA may mediate this effect.
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Unprecedented developments in cannabinoid research within the past decade include discovery of a brain (CB1) and peripheral (CB2) receptor; endogenous ligands, anandamide, and 2-arachidonylglycerol; cannabinoid drug-induced partial and inverse agonism at CB1 receptors, antagonism of NMDA receptors and glutamate, and antioxidant activity; and preferential CB1 receptor localization in areas subserving spasticity, pain, abnormal involuntary movements, seizures, and amnesia. These endogenous structures and chemicals and mechanisms are potentially new pathophysiologic substrates, and targets for novel cannabinoid treatments, of several neurological disorders.
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The effects of the primary psychoactive constituent of marijuana, delta 9-tetrahydrocannabinol, are mediated by cannabinoid receptors, CB1 and CB2. The CB1 receptors display a unique central nervous system (CNS) distribution and are present in mammalian brain at higher levels than most other known G-protein-coupled receptors. The highest levels occur in several areas involved in motor control and hippocampus. Cannabinoid effects on CNS activities, including movement, memory, nociception, endocrine regulation, thermoregulation, sensory perception, cognitive functions, and mood, correlate with the regional distribution of cannabinoid receptors and their activation of specific G-protein-mediated signal transduction systems in various brain regions.
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Steady-state auditory evoked fields were recorded from 15 subjects using a whole head MEG system. Stimuli were 800 ms trains of binaural clicks with constant stimulus onset asynchrony (SOA). Seven different SOA settings (19, 21, 23, 25, 27, 29 and 31 ms) were used to give click rates near 40 Hz. Transient responses to each click were reconstructed using a new algorithm that deconvoluted the averaged responses to the different trains. Spatio-temporal multiple dipole modelling in relation to 3D MRI scans revealed two overlapping source components in both the left and right auditory cortex. The primary sources in the medial part of Heschl's gyrus exhibited a N19-P30-N40 m pattern. The secondary, weaker sources at more lateral sites on Heschl's gyrus showed a N24-P36-N46 m pattern. When applied to transient middle latency auditory evoked fields (MAEFs) recorded at SOAs of 95-135 ms, the primary sources imaged activities similar to the deconvoluted steady-state responses, but the secondary source activities were inconsistent. Linear summation of the deconvoluted source waveforms accounted for more than 96% of the steady-state variance. This indicates that the primary activity of the auditory cortex remains constant up to high stimulation rates and is not specifically enhanced around 40 Hz.
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Mammalian tissues contain at least two types of cannabinoid receptor, CB1 and CB2, both coupled to G proteins. CB1 receptors are expressed mainly by neurones of the central and peripheral nervous system whereas CB2 receptors occur in certain non-neuronal tissues, particularly in immune cells. The existence of endogenous ligands for cannabinoid receptors has also been demonstrated. The discovery of this endogenous cannabinoid system has been paralleled by a renewed interest in possible therapeutic applications of cannabinoids, for example in the management of pain and in the suppression of muscle spasticity/spasm associated with multiple sclerosis or spinal cord injury. It has also prompted the development of a range of novel cannabinoid receptor ligands, including several that show marked selectivity for CB1 or CB2 receptors. This review summarizes current knowledge about the in vitro pharmacological properties of important CB1 and CB2 receptor ligands. Particular attention is paid to the binding properties of these ligands, to the efficacies of cannabinoid receptor agonists, as determined using cyclic AMP or [35S]GTPgammaS binding assays, and to selected examples of how these pharmacological properties can be influenced by chemical structure. The in vitro pharmacological properties of ligands that can potently and selectively oppose the actions of CB1 or CB2 receptor agonists are also described. When administered by themselves, some of these ligands produce effects in certain tissue preparations that are opposite in direction to those produced by cannabinoid receptor agonists and the possibility that the ligands producing such inverse cannabimimetic effects are inverse agonists rather than pure antagonists is discussed.
3-(1′,1′-Dimethylbutyl)-1-deoxy-Δ9-THC and related compounds: synthesis of selective ligands for the CB2 receptor
  • J W Huffman
  • JW Huffman
Huffman, J. W. et al. 3-(19,19-Dimethylbutyl)-1-deoxy-D 9 -THC and related compounds: synthesis of selective ligands for the CB2 receptor. Bioorg. Med. Chem. 7, 2905±2914 (1999).