Cannabis use in patients with multiple sclerosis

Differential migratory properties of monocytes isolated from human subjects naïve and non-naïve to Cannabis

This study evaluates the migratory potential of monocytes isolated from two groups of human subjects: naïve and non-naïve to Cannabis. Phytocannabinoids (pCB), the bioactive agents produced by the plant Cannabis, regulate the phenotype and function of immune cells by interacting with CB1 and CB2 receptors. It has been shown that agents influencing the phenotype of circulating monocytes influence the phenotype of macrophages and the outcome of immune responses. To date, nothing is known about the acute and long-term effects of pCB on human circulating monocytes. Healthy subjects were recruited for a single blood draw. Monocytes were isolated, fluorescently labeled and their migration quantified using a validated assay that employs near infrared fluorescence and modified Boyden chambers. CB1 and CB2 receptor mRNA expression was quantified by qPCR. Monocytes from all subjects (n = 10) responded to chemokine (c-c motif) ligand 2 (CCL2) and human serum stimuli. Acute application of pCB significantly inhibited both the basal and CCL2-stimulated migration of monocytes, but only in subjects non-naïve to Cannabis. qPCR analysis indicates that monocytes from subjects non-naïve to Cannabis express significantly more CB1 mRNA. The phenotype of monocytes isolated from subjects non-naïve to Cannabis is significantly different from monocytes isolated from subjects naïve to Cannabis. Only monocytes from subjects non-naïve to Cannabis respond to acute exposure to pCB by reducing their overall migratory capacity. Our study suggests that chronic exposure to Cannabis affects the phenotype of circulating monocytes and accordingly could influence outcome of inflammatory responses occurring in injured tissues.

THC and CBD oromucosal spray (Sativex®) in the management of spasticity associated with multiple sclerosis

People with multiple sclerosis may present with a wide range of disease symptoms during the evolution of the disease; among these, spasticity can have a marked impact on their well-being and quality of life. Symptom control, including spasticity, remains a key management strategy to improve the patient's well-being and functional status. However, available drug therapies for spasticity sometimes have limited benefit and they are often associated with poor tolerability. Sativex is a 1:1 mix of 9-delta-tetrahydrocannabinol and cannabidiol extracted from cloned Cannabis sativa chemovars, which is available as an oromucosal spray. Clinical experience with Sativex in patients with multiple sclerosis is accumulating steadily. Results from randomized, controlled trials have reported a reduction in the severity of symptoms associated with spasticity, leading to a better ability to perform daily activities and an improved perception of patients and their carers regarding functional status when Sativex was added to the current treatment regimen. Adverse events such as dizziness, diarrhea, fatigue, nausea, headache and somnolence occur quite frequently with Sativex, but they are generally of mild-to-moderate intensity and their incidence can be markedly reduced by gradual 'uptitration'. In summary, initial well-controlled studies with Sativex oromucosal spray administered as an add-on to usual therapy have produced promising results and highlight encouraging avenues for future research.

Acute and chronic cannabinoid extracts administration affects motor function in a CREAE model of multiple sclerosis

AIM OF THE STUDY

The multiple sclerosis is an immuno-mediated disorder of the Central Nervous System characterized by inflammatory processes and neurodegenerative changes. It has been shown that the endocannabinoid system is altered in this disease and that the exogenous cannabinoids may play a possible role in its therapeutic management. The aim of the present study was to investigate the efficacy of crude extracts of Cannabis sativa on motor symptoms in the chronic relapsing experimental autoimmune encephalomyelitis (CREAE), a murine model of multiple sclerosis.

MATERIALS AND METHODS

CREAE-induced mice were injected by different crude ethanolic extracts from Cannabis sativa, containing Δ⁹-tetrahydrocannabinol, cannabidiol, or cannabinoid-free, respectively. The effect of the combined treatment with Δ⁹-tetrahydrocannabinol and cannabidiol extracts has also been investigated. All extracts were administered in acute and chronic experimental protocols.

RESULTS

The chronic administration of Δ⁹-tetrahydrocannabinol-rich extract resulted in a significant reduction of neurological deficits that lasted until the end of the observations. The acute and chronic treatments with the cannabidiol-rich extract resulted unable to induce changes of neurological signs. However, during the relapse phase a significant decrease of neurological scores was observed. The combined treatment with Δ⁹-tetrahydrocannabinol and cannabidiol extracts was ineffective, whereas the acute administration of the cannabinoid-free extract showed a significant improvement.

CONCLUSIONS

Our study shows a patchy effect of different cannabinoid extracts on CREAE-induced motor deficits. Although the effect of crude extracts of Cannabis sativa here reported need to be further investigated to define the exact therapeutic target of each cannabinoid, it may represent a possible therapeutic approach for the management of the multiple sclerosis.

Cannabis-based medicines in multiple sclerosis--a review of clinical studies

For some years a mixture of anecdotal report and data from animal models have implied a potential role for cannabis-based medicines in ameliorating a variety of symptoms of multiple sclerosis. Only recently however have large randomised controlled trials (RCTs) examined these potential effects rigorously. At present the results of RCTs have lacked a coherent message to the prescribing clinician and reasons for such heterogeneity in cannabinoid trials are discussed.

Do cannabinoids reduce multiple sclerosis-related spasticity?

BACKGROUND

The plant Cannabis sativa contains numerous cannabinoids, which are aromatic hydrocarbons that have central nervous system effects mediated through specific cannabinoid receptors. Some patients with multiple sclerosis (MS) report symptomatic relief from spasticity, pain, and other symptoms when using smoked cannabis, and small trials have suggested some symptomatic benefit.

OBJECTIVE

Do cannabinoids improve spasticity in patients with MS?

METHODS

We addressed the question through the development of a structured, critically appraised topic. Participants included consultant and resident neurologists, clinical epidemiologists, medical librarian, and clinical content experts in the field of MS. Participants started with a clinical scenario and a structured question, devised search strategies, located and compiled the best evidence, performed a critical appraisal, synthesized the results, summarized the evidence, provided commentary, and declared bottom-line conclusions.

RESULTS

The largest randomized, placebo-controlled trial of oral cannabinoid therapy detected no improvement for MS-related spasticity as measured by the Ashworth scale. However, subjective participant reports indicated improvement in spasticity (P = 0.01), spasms (P = 0.038), sleep quality (P = 0.025), and pain (P = 0.002) without detriment to depression, fatigue, irritability, or walk time. A second randomized controlled trial, which used subjective participant report as the primary outcome, revealed the same discrepancy between subjective and objective spasticity outcome measures.

CONCLUSION

Randomized controlled trials have failed to confirm objective evidence for a beneficial effect of cannabinoids on MS-related spasticity. However, improvement in subjective assessments of spasticity and other related symptoms have been consistently noted, raising questions about the sensitivity and validity of current objective outcome instruments. Further research is warranted with regards to both outcome instrument development and the effects of cannabinoids on MS-related spasticity.

Psychopathological and cognitive effects of therapeutic cannabinoids in multiple sclerosis: a double-blind, placebo controlled, crossover study

OBJECTIVES

To study possible psychopathological symptoms and cognitive deficits, abuse induction, as well as general tolerability and effects on quality of life, fatigue and motor function in cannabis-naïve patients with multiple sclerosis (MS) treated with a free-dose cannabis plant extract (Sativex).

METHODS

In an 8-week, randomized, double-blind, placebo-controlled, parallel group crossover trial, 17 cannabis-naïve patients with MS were assessed at baseline and at the end of the cannabis and placebo phases of the trial (each of 3 weeks) by means of Symptom Checklist-90 Revised, Self-rating Anxiety Scale, Multiple Sclerosis Functional Composite (of which 1 dimension is the Paced Auditory Serial Additional Test that was used to evaluate cognition), Visual Analogue Scale on health-related quality of life, Multiple Sclerosis Impact Scale-29, and Fatigue Severity Scale.

RESULTS

Postplacebo versus postcannabinoid scores showed that no significant differences could be detected on all the variables under study. A significant positive correlation was found between Delta-9-tetrahydrocannabinol blood levels and scores at the General Symptomatic Index and at the "interpersonal sensitivity," "aggressive behaviour," and "paranoiac tendencies" subscales of the Symptom Checklist-90 Revised. No serious adverse events, abuse tendencies, or direct withdrawal symptoms were reported. Increased desire for Sativex with secondary depression was reported in 1 subject.

CONCLUSIONS

Cannabinoid treatment did not induce psychopathology and did not impair cognition in cannabis-naïve patients with MS. However, the positive correlation between blood levels of Delta-9-tetrahydrocannabinol and psychopathological scores suggests that at dosages higher than those used in therapeutic settings, interpersonal sensitivity, aggressiveness, and paranoiac features might arise, although greater statistical power would be necessary to confirm this finding.

Cannabis use in Spanish patients with multiple sclerosis: fulfilment of patients' expectations?

OBJECTIVE

Medicinal use of cannabis in chronic neurological diseases is a controversial topic of medical research and the subject of intense public debate. The aim of the study was to evaluate the prevalence of cannabis use, related factors, and degree of satisfaction in Spanish patients with multiple sclerosis (MS) prior to the establishment of medically supervised use.

METHODS

Cross-sectional, questionnaire-based survey provided during routine medical visits to consecutive patients in two university-based neurology clinics.

RESULTS

The questionnaire was returned by 175 MS patients (94.1% response rate). The prevalence of ever-use and medicinal cannabis use were 43% and 17.1%, respectively. At the time of the survey, cannabis was being used by 12.5% (5/45) of recreational and 56.7% (17/30) of medical users (p<0.001). First cannabis consumption was after MS onset in 15 (50%) medicinal users. Clinical improvement was reported by 14 (46.7%) medicinal users. Smoking use, awareness of cannabis potential benefits, pain, higher disability, and lower age were independently associated with the medicinal use of cannabis. Most patients would support a future legalisation of cannabis for the control of their symptoms and were willing to receive cannabis under medical control once legalised (83.4% of never-users, 94.5% of ever-users, p<0.05).

CONCLUSION

Almost half of our MS patients had tried cannabis at some time. However, medicinal use was low and clinical improvement after cannabis use was only reported by a subset of patients. Overall, MS patients were highly motivated for a future medically controlled use.

Current status of cannabis treatment of multiple sclerosis with an illustrative case presentation of a patient with MS, complex vocal tics, paroxysmal dystonia, and marijuana dependence treated with dronabinol

Pain, spasticity, tremor, spasms, poor sleep quality, and bladder and bowel dysfunction, among other symptoms, contribute significantly to the disability and impaired quality of life of many patients with multiple sclerosis (MS). Motor symptoms referable to the basal ganglia, especially paroxysmal dystonia, occur rarely and contribute to the experience of distress. A substantial percentage of patients with MS report subjective benefit from what is often illicit abuse of extracts of the Cannabis sativa plant; the main cannabinoids include delta-9-tetrahydrocannabinol (delta9-THC) and cannabidiol. Clinical trials of cannabis plant extracts and synthetic delta9-THC provide support for therapeutic benefit on at least some patient self-report measures. An illustrative case is presented of a 52-year-old woman with MS, paroxysmal dystonia, complex vocal tics, and marijuana dependence. The patient was started on an empirical trial of dronabinol, an encapsulated form of synthetic delta9-THC that is usually prescribed as an adjunctive medication for patients undergoing cancer chemotherapy. The patient reported a dramatic reduction of craving and illicit use; she did not experience the "high" on the prescribed medication. She also reported an improvement in the quality of her sleep with diminished awakenings during the night, decreased vocalizations, and the tension associated with their emission, decreased anxiety and a decreased frequency of paroxysmal dystonia.

Psychiatric issues in multiple sclerosis

MDD and anxiety disorders are highly prevalent among persons who have MS and have been associated with decreased adherence to MS treatment and poorer functional status and quality of life. Effective treatment is available for MDD, but this disorder continues to be underdetected and undertreated by MS providers. Treatment with pharmacotherapy is particularly challenging in this patient population, given the somatic symptom overlap between MS and depression and the increased burden of side effects. Larger randomized, controlled trials are needed to elucidate further the effectiveness of pharmacotherapy and to identify subgroups of patients who would benefit from this type of treatment for depression. There have been few rigorous studies of the prevalence and impact of anxiety disorders, substance use disorders, or serious mental illness such as bipolar disorder or schizophrenia, in MS samples.

Cannabinoid control of neuroinflammation related to multiple sclerosis

The cannabis plant (Cannabis sativa) has been known by many names but the question remains 'Can we call it medicine?' There has been renewed interest in the value of cannabis for the control of neuroinflammatory conditions such as multiple sclerosis, where it has been shown to have some effect on spasticity and pain both experimentally and in clinical trials in humans. However, in addition to symptom control potential, the question remains whether cannabinoids can modify the neuroinflammatory element which drives relapsing neurological attacks and the accumulation of progressive disability. In experimental studies it has been recently shown that synthetic cannabinoids can affect the immune response both indirectly via CB1 receptor-mediated signalling nerve centres controlling the systemic release of immunosuppressive molecules and directly by CB2 receptor-mediated inhibition of lymphocyte and macrophage/microglial cell function. However, these immunosuppressive possibilities that would limit the frequency of relapsing attacks will probably not be realized clinically, following use of medical cannabis, due to dose constraints. However, cannabinoids may still affect the glial response within the damaged central nervous system, which facilitate the slow, neurodegenerative processes that account for progressive neurodegeneration, and therefore may have utility in addition to value of cannabis-related drugs for symptom control.

Short- and long-term plasticity of the endocannabinoid system in neuropsychiatric and neurological disorders

The activity of the endocannabinoid system, in terms of the levels of the endocannabinoids and of cannabinoid receptors, or of the functional coupling of the latter to a biological response, undergoes to remodelling during pathological conditions. In the CNS, these changes, depending also on the nature of the disorder, can be transient or long-lasting, occur only in those tissues involved in the pathological condition and usually aim at restoring the physiological homeostasis by reducing excitotoxicity, inflammation and neuronal death. However, during chronic disorders, prolonged activation of the endocannabinoid system might also contribute to the symptoms of the pathology. Whilst acute changes of the tissue levels of the endocannabinoids reflect the "on demand" nature of their biosynthesis and release, and hence are effected mostly through regulation of the biosynthetic enzymes, chronic changes seem to be mostly due to longer-lasting alterations in the expression of anabolic and catabolic enzymes. The possibility of obtaining therapeutic advantage from endocannabinoid plasticity in neuropsychiatric and neurological disorders is discussed in this review article.