Cannabinoids for the Treatment of Agitation and Aggression in Alzheimer's Disease

Medical cannabinoids for painful symptoms in patients with severe dementia: a randomized, double-blind cross-over placebo-controlled trial protocol

Background

In an observational study in Geneva (Switzerland), we found that administering a standardized THC/CBD oil was feasible, safe, and beneficial in an elderly polymedicated population with severe dementia, behavioral troubles, and pain. Those findings need to be confirmed in a randomized clinical trial.

Objectives

The MedCanDem trial is a randomized, double-blind cross-over placebo-controlled trial to study the efficacy of cannabinoids in improving painful symptoms during severe dementia disorders in patients living in long-term care facilities in Geneva. This manuscript describes the MedCanDem trial protocol.

Materials and methods

Participants will be patients suffering from severe dementia associated with pain and behavioral troubles and living in long-term care facilities. We selected five facilities specialized in caring for severely demented patients in Geneva (Switzerland). A total of 24 subjects will be randomized 1:1 to the sequence study intervention/placebo or the sequence placebo/study intervention. Patients will receive study intervention treatment or placebo for eight weeks, and then after a one-week wash-out, treatments will be inversed for another eight weeks. The intervention will be a standardized THC/CBD 1:2 oil extract, and the placebo will be a hemp seed oil. The primary outcome is the reduction from the baseline of the Cohen-Mansfield score; secondary outcomes include the reduction in the Doloplus scale, the reduction of rigidity, the monitoring of concomitant drugs prescription and de-prescription, the safety assessment, and a pharmacokinetic evaluation. The primary and secondary outcomes will be assessed at the baseline, after 28 days, and at the end of both study periods. In addition, safety laboratory analysis, pharmacokinetic evaluation, and therapeutic drug monitoring for the cannabinoids will be evaluated through a blood sample analysis conducted at the beginning and the end of both study periods.

Discussion and conclusion

This study will allow us to confirm the clinical results observed during the observational study. It represents one of the few studies aiming to prove natural medical cannabis efficacy in a population of non-communicating patients with severe dementia, experimenting with behavioral troubles, pain, and rigidity.

Trial registration

The trial has Swissethics authorization (BASEC 2022-00999), and it is registered on clinicaltrials.gov (NCT05432206) and the SNCTP (000005168).

Promising candidates from drug clinical trials: Implications for clinical treatment of Alzheimer's disease in China

Alzheimer's disease is the most common neurodegenerative disease. Prior to 2017, National Medical Products Administration approved only four drugs to treat Alzheimer's disease, including three cholinesterase inhibitors and one N-methyl-D-aspartate receptor antagonist. We queried ClinicalTrials.gov to better understand Alzheimer's drug development over the past 5 years and found 16 promising candidates that have entered late-stage trials and analyzed their impact on clinical treatment of Alzheimer's disease in China. The 16 compounds selected include disease-modifying therapies and symptomatic therapies. The research and development pipeline now focuses on disease-modifying therapies such as gantenerumab, aducanumab, ALZ-801, ALZT-OP1, donanemab, lecanemab, simufilam, NE3107, semaglutide, and GV-971, which could put an end to the situation where Alzheimer's patients in China have no effective treatment alternatives. The reuse of drugs or combinations currently under investigation for the psychiatric treatment of Alzheimer's disease, including AXS-05, AVP-786, nabilone, brexpiprazole, methylphenidate, and pimavanserin, could provide physicians with additional treatment options. Although most of these drugs have not been explored in China yet, due to the current development trend in this field in China, it is expected that China will be involved in research on these drugs in the future.

Risks and benefits of current and novel drugs to treat agitation in Alzheimer's disease

INTRODUCTION

At present, no pharmacological interventions have been approved for the treatment of agitation in Alzheimer's disease (AD), an important neuropsychiatric symptom that has been linked to increased mortality and greater caregiver burden. Antipsychotics offer some benefit, but increase the risk of adverse events such as falls, extrapyramidal symptoms, stroke, and mortality. Over the past 10 years, several new and repurposed medications have shown promise for treating AD-associated agitation.

AREAS COVERED

We review the risks and benefits of emerging therapies for agitation in AD, which include newer atypical antipsychotics, selective serotonin reuptake inhibitors, cannabinoids, and dextromethorphan combination products. Other drugs such as mirtazapine, prazosin, and lithium are also discussed. Clinicaltrials.gov, PubMed/MEDLINE, EMBASE and Cochrane Central databases were searched for relevant studies from 1 January 2012 to 1 May 2022.

EXPERT OPINION

At the present time, there are no pharmacological interventions for the treatment of agitation in AD whose benefits clearly outweigh their potential safety concerns. Therefore, management of agitation in AD should primarily be based on non-pharmacological approaches. When medications are considered necessary, they should only be initiated with the caregiver's appreciation of their risks and benefits and with careful and ongoing assessment of their safety.

Cannabinoid extract in microdoses ameliorates mnemonic and nonmnemonic Alzheimer's disease symptoms: a case report

BACKGROUND

Cannabinoid-based therapy has been shown to be promising and is emerging as crucial for the treatment of cognitive deficits, mental illnesses, and many diseases considered incurable. There is a need to find an appropriate therapy for Alzheimer's disease, and cannabinoid-based therapy appears to be a feasible possibility.

CASE PRESENTATION

This report addresses the beneficial effect of cannabinoids in microdoses on improving memory and brain functions of a patient with mild-stage Alzheimer's disease. The patient is a 75-year-old white man presenting with main symptoms of memory deficit, spatial and temporal disorientation, and limited daily activity. The experimental therapeutic intervention was carried out for 22 months with microdoses of a cannabis extract containing cannabinoids. Clinical evaluations using Mini-Mental State Examination and Alzheimer's Disease Assessment Scale-Cognitive Subscale were performed.

CONCLUSIONS

Here we provide original evidence that cannabinoid microdosing could be effective as an Alzheimer's disease treatment while preventing major side effects. This is an important step toward dissociating cannabinoids' health-improving effects from potential narcotic-related limitations.

Cannabinoids in the management of behavioral, psychological, and motor symptoms of neurocognitive disorders: a mixed studies systematic review

Aim

We undertook this systematic review to determine the efficacy and safety of cannabis-based medicine as a treatment for behavioral, psychological, and motor symptoms associated with neurocognitive disorders.

Methods

We conducted a PRISMA-guided systematic review to identify studies using cannabis-based medicine to treat behavioral, psychological, and motor symptoms among individuals with Alzheimer's disease (AD) dementia, Parkinson’s disease (PD), and Huntington’s disease (HD). We considered English-language articles providing original data on three or more participants, regardless of design.

Findings

We identified 25 studies spanning 1991 to 2021 comprised of 14 controlled trials, 5 pilot studies, 5 observational studies, and 1 case series. In most cases, the cannabinoids tested were dronabinol, whole cannabis, and cannabidiol, and the diagnoses included AD (n = 11), PD (n = 11), and HD (n = 3). Primary outcomes were motor symptoms (e.g., dyskinesia), sleep disturbance, cognition, balance, body weight, and the occurrence of treatment-emergent adverse events.

Conclusions

A narrative summary of the findings from the limited number of studies in the area highlights an apparent association between cannabidiol-based products and relief from motor symptoms in HD and PD and an apparent association between synthetic cannabinoids and relief from behavioral and psychological symptoms of dementia across AD, PD, and HD. These preliminary conclusions could guide using plant-based versus synthetic cannabinoids as safe, alternative treatments for managing neuropsychiatric symptoms in neurocognitive vulnerable patient populations.

Cannabinoids for behavioral symptoms in severe dementia: Safety and feasibility in a long-term pilot observational study in nineteen patients

Context

The management of behavioral symptoms and rigidity in patients with dementia constitutes a significant challenge. Short-term studies suggest an interest in the use of medical cannabis, but long-term data are lacking.

Objectives

The objective of this study was to investigate the feasibility and long-term safety of administering tetrahydrocannabinol/cannabidiol (THC/CBD) treatment as an additional drug to a poly medicated population with severe dementia, evaluate clinical improvements, and collect information on the pharmacokinetics of cannabinoids and possible drug-drug interactions.

Methods

A prospective observational study of patients with severe dementia living in a long-term care home to whom the physicians had prescribed a medical cannabis treatment. Data were collected over 2 years. We assessed the changes in medical cannabis dosages, safety parameters, variations in neuropsychiatric problems, agitation, rigidity, the most invalidating daily activity, and disabling behavior trouble scores. We evaluated the pharmacokinetics of cannabinoids by measuring plasma levels and analyzing the enzymatic activity.

Results

We assessed 19 patients (81.4 years-17 women and two men) receiving an average of 12.4 mg THC/24.8 mg CBD per day for up to 13 months, with no reported problems related to the treatment and limited adverse drug reactions. Clinical scores showed a marked improvement that was stable over time, deprescription of other medications, and care facilitated. The pharmacokinetic evaluation showed an expected slight reduction in the enzymatic activity of CYP1A2 and CYP2C19.

Conclusion

A long-term THC/CBD (1:2) medication can be administered safely and with overall positive clinical improvement to poly medicated older adults with severe dementia and associated problems. The results must be confirmed in a randomized trial.

Blood-based biomarkers of agitation in Alzheimer's disease: Advances and future prospects

Agitation is a common neuropsychiatric symptom that becomes more prevalent as Alzheimer's disease (AD) increases in severity. The treatment of agitation is an urgent and unmet need due to the poor outcomes associated with it, its disruptive impact on patients and caregivers, and the lack of efficacious and safe treatments. Recent research on agitation in AD with blood-based biomarkers has advanced the search for its biomarkers beyond the brain and provides new insights to understand its mechanisms and improve treatments. Here, we reviewed studies of blood-based biomarkers of agitation in AD, which show that inflammatory biomarkers are increased in patients with agitation, may predict the development of agitation, and are associated with symptom severity. In addition, they may also track symptom severity and response to treatment. Other biomarkers associated with agitation include markers of oxidative stress, brain cholesterol metabolism, motor activity, and clusterin, a chaperone protein. These results are promising and need to be replicated. Preliminary evidence suggests a role for these biomarkers in interventional studies for agitation to predict and monitor treatment response, which may eventually help enrich study samples and deliver therapy likely to benefit individual patients. Advances in blood-based biomarkers of AD including those identified in "-omic" studies and high sensitivity assays provide opportunities to identify new biomarkers of agitation. Future studies of agitation and its treatment should investigate blood-based biomarkers to yield novel insights into the neurobiological mechanisms of agitation, monitoring symptoms and response to treatment, and to identify patients likely to respond to treatments.

Cannabis, a Miracle Drug with Polyvalent Therapeutic Utility: Preclinical and Clinical-Based Evidence

Cannabis sativa L. is an annual herbaceous dioecious plant which was first cultivated by agricultural human societies in Asia. Over the period of time, various parts of the plant like leaf, flower, and seed were used for recreational as well as therapeutic purposes. The main chemical components of Cannabis sativa are termed as cannabinoids, among them the key psychoactive constituent is Δ-9-tetrahydrocannabinol and cannabidiol (CBD) as active nonpsychotic constituent. Upon doing extensive literature review, it was found that cannabis has been widely studied for a number of disorders. Very recently, a pure CBD formulation, named Epidiolex, got a green flag from both United States Food and Drug Administration and Drug Enforcement Administration for 2 rare types of epilepsies. This laid a milestone in medical cannabis research. This review intends to give a basic and extensive assessment, from past till present, of the ethnological, plant, chemical, pharmacological, and legal aspects of C. sativa. Further, this review contemplates the evidence the studies obtained of cannabis components on Alzheimer's, Parkinson's, amyotrophic lateral sclerosis, multiple sclerosis, emesis, epilepsy, chronic pain, and cancer as a cytotoxic agent as well as a palliative therapy. The assessment in this study was done by reviewing in extensive details from studies on historical importance, ethnopharmacological aspects, and legal grounds of C. sativa from extensive literature available on the scientific databases, with a vision for elevating further pharmaceutical research to investigate its total potential as a therapeutic agent.

Cannabinoids for the treatment of dementia

BACKGROUND

Dementia is a common chronic condition, mainly affecting older adults, characterised by a progressive decline in cognitive and functional abilities. Medical treatments for dementia are limited. Cannabinoids are being investigated for the treatment of dementia.

OBJECTIVES

To determine the efficacy and safety of cannabinoids for the treatment of dementia.

SEARCH METHODS

We searched ALOIS - the Cochrane Dementia and Cognitive Improvement Group's Specialised Register - on 8 July 2021, using the terms cannabis or cannabinoid or endocannabinoid or cannabidiol or THC or CBD or dronabinol or delta-9-tetrahydrocannabinol or marijuana or marihuana or hashish. The register contains records from all major healthcare databases (the Cochrane Library, MEDLINE, Embase, PsycINFO, CINAHL, LILACS), as well as from many clinical trials registries and grey literature sources.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) of cannabinoids for the treatment of dementia. We included participants of any age and of either sex with diagnosed dementia of any subtype, or with unspecified dementia of any severity, from any setting. We considered studies of cannabinoids administered by any route, at any dose, for any duration, compared with placebo, no treatment, or any active control intervention.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened and selected studies for inclusion, extracted data, and assessed the risk of bias in included studies. When necessary, other review authors were involved in reaching consensus decisions. We conducted meta-analyses using a generic inverse variance fixed-effect model to derive estimates of effect size. We used GRADE methods to assess our confidence in the effect estimates.

MAIN RESULTS

We included four studies (126 participants) in this review. Most participants had Alzheimer's disease; a few had vascular dementia or mixed dementia. Three studies had low risk of bias across all domains; one study had unclear risk of bias for the majority of domains.  The included studies tested natural delta-9-tetrahydrocannabinol (THC) (Namisol) and two types of synthetic THC analogue (dronabinol and nabilone). Three trials had a cross-over design. Interventions were applied over 3 to 14 weeks; one study reported adverse events over 70 weeks of follow-up. One trial was undertaken in the USA, one in Canada, and two in The Netherlands. Two studies reported non-commercial funding, and two studies were conducted with the support of both commercial and non-commercial funding. Primary outcomes in this review were changes in global and specific cognitive function, overall behavioural and psychological symptoms of dementia (BPSD), and adverse events. We found very low-certainty evidence suggesting there may be little or no clinically important effect of a synthetic THC analogue on cognition assessed with the standardised Mini-Mental State Examination (sMMSE) (mean difference (MD) 1.1 points, 95% confidence interval (CI) 0.1 to 2.1; 1 cross-over trial, 28 participants).  We found low-certainty evidence suggesting there may be little or no clinically important effect of cannabinoids on overall behavioural and psychological symptoms of dementia assessed with the Neuropsychiatric Inventory (or its modified nursing home version) (MD -1.97, 95% CI -3.87 to -0.07; 1 parallel group and 2 cross-over studies, 110 participants). All included studies reported data on adverse events. However, the total number of adverse events, the total numbers of mild and moderate adverse events, and the total number of serious adverse events (SAEs) were not reported in a way that permitted meta-analysis.  There were no clear differences between groups in numbers of adverse events, with the exception of sedation (including lethargy), which was more frequent among participants taking nabilone (N = 17) than placebo (N = 6) (odds ratio (OR) 2.83, 95% CI 1.07 to 7.48; 1 cross-over study, 38 participants). We judged the certainty of evidence for adverse event outcomes to be low or very low due to serious concerns regarding imprecision and indirectness.

AUTHORS' CONCLUSIONS

Based on data from four small, short, and heterogeneous placebo-controlled trials, we cannot be certain whether cannabinoids have any beneficial or harmful effects on dementia. If there are benefits of cannabinoids for people with dementia, the effects may be too small to be clinically meaningful. Adequately powered, methodologically robust trials with longer follow-up are needed to properly assess the effects of cannabinoids in dementia.

Cannabinoid receptors distribution in mouse cortical plasma membrane compartments

The type 1 and type 2 cannabinoid receptors (CB1 and CB2 receptors) are class A G protein-coupled receptors (GPCRs) that are activated by endogenous lipids called endocannabinoids to modulate neuronal excitability and synaptic transmission in neurons throughout the central nervous system (CNS), and inflammatory processes throughout the body. CB1 receptor is one of the most abundant GPCRs in the CNS and is involved in many physiological and pathophysiological processes, including mood, appetite, and nociception. CB2 receptor is primarily found on immunomodulatory cells of both the CNS and the peripheral immune system. In this study, we isolated lipid raft and non-lipid raft fractions of plasma membrane (PM) from mouse cortical tissue by using cold non-ionic detergent and sucrose gradient centrifugation to study the localization of CB1 receptor and CB2 receptor. Lipid raft and non-lipid raft fractions were confirmed by flotillin-1, caveolin-1 and transferrin receptor as their protein biomarkers. Both CB1 receptor and CB2 receptor were found in non-raft compartments that is inconsistent with previous findings in cultured cell lines. This study demonstrates compartmentalization of both CB1 receptor and CB2 receptor in cortical tissue and warrants further investigation of CB1 receptor and CB2 receptor compartmental distribution in various brain regions and cell types.

Cannabis Use in Older Adults: A Perspective

The prevalence of cannabis use among older adults (aged 65 and above) for both recreational and medicinal purposes has significantly increased in recent years. Information regarding the safety of cannabis in this population is important since aging is associated with metabolic changes, multiple morbidities, increases in prescription medication use, and an overall decline in functioning. In this Perspectives article, we review special considerations pertinent to older adults-specifically, the impact of cannabis on cognition and on falls and injuries, its drug interactions, and its potential medicinal applications for treating the behavioral and psychological symptoms of dementia. Knowledge about the role of cannabis in brain health, injury risk, and drug interactions remains limited since the available evidence stems primarily from adolescent and young adult cohorts, plus a limited number of small observational studies with older adults. In terms of utilizing certain cannabinoids to treat the behavioral and psychological symptoms of dementia, some studies have found promising results, but because of the lack of consistency in the literature, it is premature to draw conclusions. Controlled research trials specifically with geriatric participants are needed to understand the effects of cannabis use in this vulnerable population.

Recent developments in geriatric psychopharmacology

INTRODUCTION

There is a tremendous growing need to address the burden of geriatric psychiatric disorders. Recent developments relevant to geriatric psychiatry have focused on Alzheimer's disease (AD), severe/refractory depression, and cancer/end of life care.

AREAS COVERED

This is a non-systematic, narrative review (databases and websites for search: PubMed, Google Scholar, Medscape, ClinicalTrials.gov; focusing on the last 6 years), and covers developments in disease-modifying therapies for AD, diagnostic radiotracers for AD, medications for neuropsychiatric symptoms of dementia, ketamine/esketamine, psychedelics, and cannabinoids.

EXPERT OPINION

The focus of on-going trials of anti-amyloid agents has been on individuals with very early stage AD; several agents are under phase 3 investigation, and aducanumab is under FDA review. Amyloid and tau PET scans have been approved by the FDA to assist in the diagnoses of AD. Promising pharmaceuticals for neuropsychiatric symptoms of dementia include pimavanserin, brexpiprazole, escitalopram, dextromethorphan/quinidine, and lithium. Esketamine, although approved for treatment-resistant depression in general adults, failed to demonstrate efficacy in elderly patients in a phase 3 trial. There is preliminary evidence for benefit of psychedelic-assisted psychotherapy in end-of-life and cancer-related depression/anxiety. Evidence for the use of cannabinoids is currently lacking.

Recent Advances in the Potential of Cannabinoids for Neuroprotection in Alzheimer's, Parkinson's, and Huntington's Diseases

Three prevalent neurodegenerative diseases, Parkinson's, Alzheimer's, and Huntington's are in need of symptomatic relief of slowing disease progression or both. This chapter focuses on the potential of cannabinoids to afford neuroprotection, i.e. avoid or retard neuronal death. The neuroprotective potential of cannabinoids is known from the work in animal models and is mediated by the two cannabinoid receptors (CB₁/CB₂) and eventually, by their heteromers, GPR55, orphan receptors (GPR3/GPR6/GPR12/GPR18), or PPARγ. Now, there is the time to translate the findings into patients. The chapter takes primarily into account advances since 2016 and addresses the issue of proving neuroprotection in humans. One recent discovery is the existence of activated microglia with neuroprotective phenotype; cannabinoids are good candidates to skew phenotype, especially via glial CB₂ receptors (CB₂R), whose targeting has, a priori, less side effects those targeting the CBs₁ receptor (CB₁R), which are expressed in both neurons and glia. The fact that a cannabis extract (SativexTM) is approved for human therapy, such that cannabis use will likely be legalized in many countries and different possibilities that cannabinoid pharmacology suggests a successful route of cannabinoids (natural or synthetic) all the way to be approved and used in the treatment of neurodegeneration.

Psychiatric Disorders and Cannabinoid Receptors

With the increasing global use of medical and adult recreational use of cannabis and cannabinoids, this chapter provides overview of evidence from animal and human studies on psychiatric disorders and cannabinoid receptors. We review and present evaluation of the relationship between changes in the ECS and psychiatric disorders. Evidence suggests the existence of a relationship between changes in components of the ECS, and some of the symptoms present in psychiatric disorders. Both CB1Rs and CB2Rs are components of the endocannabinoid system with different cellular and tissue localization patterns that are differentially expressed in the CNS and PNS and are emerging targets for the treatment of number psychiatric disorders. As cannabis preparations are widely used for recreation globally, it is predictable that cannabis use disorders (CUDs) will increase and there is currently no available treatment for CUDs. Although major advances have been reported from cannabinoid and ECS research, there are gaps in scientific knowledge on long-term consequences of cannabis use. Adolescent and cannabis use during pregnancy presents further challenges, and more research will uncover the signaling pathways that couple the gut microbiota with the host ECS. Development of cannabis and cannabinoid nanomedicine for nanotherapy will certainly overcome some of the shortcomings and challenges in medicinal and recreational use of cannabis and cannabinoids. Thus, nanotechnology will allow targeted delivery of cannabinoid formulations with the potential to elevate their use to scientifically validated nanotherapeutic applications as the field of cannabis nanoscience matures.

Recognition and management of agitation in acute mental health services: a qualitative evaluation of staff perceptions

BACKGROUND

Agitation among patients is a common and distressing behaviour across a variety of health care settings, particularly inpatient mental health. Unless recognised early and effectively managed it can lead to aggression and personal injury. The aim of this paper is to explore the experiences of mental health nurses in recognising and managing agitation in an inpatient mental health setting and the alignment of these experiences with best practice and person-centred care.

METHODS

This study used a descriptive qualitative methodology. Semi-structured focus group interviews were conducted with 20 nurses working in a mental health unit in 2018. Nursing staff described their experiences of assessing and managing agitation. Descriptive and Thematic Analysis were undertaken of the transcribed focus group dialogue.

RESULTS

Nurses combined their clinical knowledge, assessment protocols and training with information from patients to make an individualised assessment of agitation. Nurses also adopted an individualised approach to management by engaging patients in decisions about their care. In keeping with best practice recommendations, de-escalation strategies were the first choice option for management, though nurses also described using both coercive restraint and medication under certain circumstances. From the perspective of patient-centred care, the care provided aligned with elements of person-centred care nursing care.

CONCLUSION

The findings suggest that clinical mental health nurses assess and manage agitation, with certain exceptions, in line with best practice and a person-centred care nursing framework.

The positive and negative cardiovascular effects of cannabis

INTRODUCTION

The use of cannabis and its derivatives have increased steadily over the past few decades, prompting patients and clinicians to increasingly inquire about its health effects and safety profile. However, despite promising evidence suggesting therapeutic utilization, cannabis remains a controlled substance in most countries and is largely considered to have no medical or recreational benefit; thus, a lack of observational studies and randomized control trials exist to outline positive and negative health implications. Ultimately, this leaves patients, health-care professionals, and policymakers without necessary evidence required to make informed decisions on cannabis use.

AREAS COVERED

This review outlines cannabis in a clinical setting and delves into specific effects of cannabinoids on cardiovascular health and disease. It discusses positive and negative health implications associated with cannabis, mechanisms in cardiovascular disease, and reveals methods guiding cannabis use in the clinical setting.

EXPERT OPINION

Advances in research are necessary to guide decisions regarding cannabinoid use. Countries that have federally legalized cannabis have a unique opportunity to study cardiovascular implications in an unbiased and comprehensive manner. Ultimately, as cannabis use will inevitably increase, researchers, clinicians, and policymakers must work together to ensure cannabis is utilized in a way that is therapeutically beneficial.

Emerging Promise of Cannabinoids for the Management of Pain and Associated Neuropathological Alterations in Alzheimer's Disease

Alzheimer's disease (AD) is an irreversible chronic neurodegenerative disorder that occurs when neurons in the brain degenerate and die. Pain frequently arises in older patients with neurodegenerative diseases including AD. However, the presence of pain in older people is usually overlooked with cognitive dysfunctions. Most of the times dementia patients experience moderate to severe pain but the development of severe cognitive dysfunctions tremendously affects their capability to express the presence of pain. Currently, there are no effective treatments against AD that emphasize the necessity for increasing research to develop novel drugs for treating or preventing the disease process. Furthermore, the prospective therapeutic use of cannabinoids in AD has been studied for the past few years. In this regard, targeting the endocannabinoid system has considered as a probable therapeutic strategy to control several associated pathological pathways, such as mitochondrial dysfunction, excitotoxicity, oxidative stress, and neuroinflammation for the management of AD. In this review, we focus on recent studies about the role of cannabinoids for the treatment of pain and related neuropathological changes in AD.

Receptor mechanisms mediating the anti-neuroinflammatory effects of endocannabinoid system modulation in a rat model of migraine

Calcitonin gene-related peptide (CGRP), substance P and dural mast cells are main contributors in neurogenic inflammation underlying migraine pathophysiology. Modulation of endocannabinoid system attenuates migraine pain, but its mechanisms of action remain unclear. We investigated receptor mechanisms mediating anti-neuroinflammatory effects of endocannabinoid system modulation in in vivo migraine model and ex vivo hemiskull preparations in rats. To induce acute model of migraine, a single dose of nitroglycerin was intraperitoneally administered to male rats. Moreover, isolated ex vivo rat hemiskulls were prepared to study CGRP and substance P release from meningeal trigeminal afferents. We used methanandamide (cannabinoid agonist), rimonabant (cannabinoid receptor-1 CB1 antagonist), SR144528 (CB2 antagonist) and capsazepine (transient receptor potential vanilloid-1 TRPV1 antagonist) to explore effects of endocannabinoid system modulation on the neurogenic inflammation, and possible involvement of CB1, CB2 and TRPV1 receptors during endocannabinoid effects. Methanandamide attenuated nitroglycerin-induced CGRP increments in in vivo plasma, trigeminal ganglia and brainstem and also in ex vivo hemiskull preparations. Methanandamide also alleviated enhanced number and degranulation of dural mast cells induced by nitroglycerin. Rimonabant, but not capsazepine or SR144528, reversed the attenuating effects of methanandamide on CGRP release in both in vivo and ex vivo experiments. Additionally, SR144528, but not rimonabant or capsazepine, reversed the attenuating effects of methanandamide on dural mast cells. However, neither nitroglycerin nor methanandamide changed substance P levels in both in vivo and ex vivo experiments. Methanandamide modulates CGRP release in migraine-related structures via CB1 receptors and inhibits the degranulation of dural mast cells through CB2 receptors. Selective ligands targeting CB1 and CB2 receptors may provide novel and effective treatment strategies against migraine.

Cannabinoids for the Neuropsychiatric Symptoms of Dementia: A Systematic Review and Meta-Analysis

BACKGROUND

In 2016, the global number of individuals living with dementia was 43.8 million, representing a 117% increase from 1990-mainly due to increases in aging and population growth. Up to 90% of individuals with dementia experience neuropsychiatric symptoms (NPS). However, the limitations of current treatments for NPS have drivent he search for safer pharmacotherapies-including cannabinoids.

AIM

To assess the efficacy and acceptability of cannabinoids for the treatment of NPS in individuals with dementia.

DESIGN

Systematic review and meta-analysis of clinical trials.

SETTING AND PARTICIPANTS

Of 6,902 papers, 9 were eligible (n = 205, 44% female, 78 ± 7 years, 85% Alzheimer disease). Trials were in North America and Europe and explored tetrahydrocannabinol (n = 3), dronabinol (n = 5), or nabilone (n = 1).

MEASUREMENT

Titles/abstracts were independently screened by one reviewer and reviewed by a second. Full-text screening was by two reviewers with discrepancies resolved via a third reviewer. We extracted data on the standardized mean difference (SMD) for several NPS instruments, trial completion, and adverse events. Data were pooled using random-effects models.

FINDINGS

Cannabinoids led to significant improvements across NPS instruments, including the Cohen Mansfield Agitation Inventory (SMD = -0.80; 95% confidence interval [CI], -1.45 to -0.16), the Neuropsychiatric Inventory (SMD = -0.61; CI, -1.07 to -0.15), and nocturnal actigraphy (SMD = -1.05; CI, -1.56 to -0.54h). Cannabinoids were well-tolerated, with an overall trial completion rate of 93% (193/205) and no serious treatment-related adverse events. Treatment efficacy was associated with baseline dementia severity and dose, but not dementia subtype, age, or sex. The overall study quality was rated as low.

CONCLUSIONS

There is preliminary evidence for the efficacy and tolerability of cannabinoids as treatments for NPS. Population-based studies are needed to characterize their real-world effectiveness and acceptability.

Targeting the endocannabinoid system: a predictive, preventive, and personalized medicine-directed approach to the management of brain pathologies

Cannabis-inspired medical products are garnering increasing attention from the scientific community, general public, and health policy makers. A plethora of scientific literature demonstrates intricate engagement of the endocannabinoid system with human immunology, psychology, developmental processes, neuronal plasticity, signal transduction, and metabolic regulation. Despite the therapeutic potential, the adverse psychoactive effects and historical stigma, cannabinoids have limited widespread clinical application. Therefore, it is plausible to weigh carefully the beneficial effects of cannabinoids against the potential adverse impacts for every individual. This is where the concept of "personalized medicine" as a promising approach for disease prediction and prevention may take into the account. The goal of this review is to provide an outline of the endocannabinoid system, including endocannabinoid metabolizing pathways, and will progress to a more in-depth discussion of the therapeutic interventions by endocannabinoids in various neurological disorders.

Cannabinoids in the Older Person: A Literature Review

INTRODUCTION

Medical cannabinoids have received significant mainstream media attention in recent times due to an evolving political and clinical landscape. Whilst the efficacy of cannabinoids in the treatment of some childhood epilepsy syndromes is increasingly recognized, medical cannabinoids may also have potential clinical roles in the treatment of older adults. Prescribing restrictions for medical cannabinoids in certain jurisdictions (including the UK) has recently been relaxed. However, few geriatricians have the detailed knowledge or awareness of the potential risks or rewards of utilizing cannabinoids in the older person; even fewer geriatricians have direct experience of using these drugs in their own clinical practice. Older persons are more likely to suffer from medical illness representing potential indications for medical cannabinoids (e.g., pain); equally they may be more vulnerable to any adverse effects.

AIM

This narrative literature review aims to provide a brief introduction for the geriatrician to the potential indications, evidence-base, contra-indications and side effects of medical cannabinoids in older people.

METHODS

A search was conducted of CENTRAL, Medline, Embase, CINAHL and psycINFO, Cochrane and Web of Science databases. Reference lists were hand searched. Abstracts and titles were screened, followed by a full text reading of relevant articles.

RESULTS

35 studies were identified as relevant for this narrative review.

CONCLUSIONS

Cannabinoids demonstrate some efficacy in the treatment of pain and chemotherapy-related nausea; limited data suggest potential benefits in the treatment of spasticity and anxiety. Risks of cannabinoids in older patients appear to be moderate, and their frequency comparable to other analgesic drug classes. However, the quality of research is weak, and few older patients have been enrolled in cannabinoid studies. Dedicated research is needed to determine the efficiency and safety of cannabinoids in older patients.

Management of Dementia-Related Psychosis, Agitation and Aggression: A Review of the Pharmacology and Clinical Effects of Potential Drug Candidates

Along with cognitive decline, 90% of patients with dementia experience behavioral and psychological symptoms of dementia, such as psychosis, aggression, agitation, and depression. Atypical antipsychotics are commonly prescribed off-label to manage certain symptoms, despite warnings from the regulatory agencies regarding the increased risk of mortality associated with their use in elderly patients. Moreover, these compounds display a limited clinical efficacy, mostly owing to the fact that they were developed to treat schizophrenia, a disease characterized by neurobiological deficits. Thus, to improve clinical efficacy, it has been suggested that patients with dementia should be treated with exclusively designed and developed drugs that interact with pharmacologically relevant targets. Within this context, numerous studies have suggested druggable targets that might achieve therapeutically acceptable pharmacological profiles. Based on this, several different drug candidates have been proposed that are being investigated in clinical trials for behavioral and psychological symptoms of dementia. We highlight the recent advances toward the development of therapeutic agents for dementia-related psychosis and agitation/aggression and discuss the relationship between the relevant biological targets and their etiology. In addition, we review the compounds that are in the early stage of development (discovery or preclinical phase) and those that are currently being investigated in clinical trials for dementia-related psychosis and agitation/aggression. We also discuss the mechanism of action of these compounds and their pharmacological utility in patients with dementia.

A Systematic Review of the Neurocognitive Effects of Cannabis Use in Older Adults

Purpose of Review

Older adults currently represent the fastest growing demographic of cannabis users, yet few studies have investigated the effects of cannabis use on cognitive functioning in aging. We conducted a systematic review of the recent literature examining cognitive outcomes associated with cannabis use in older adults, with and without neurocognitive disorders, to clarify the potential neuroprotective benefits and risks of cognitive decline in this population.

Recent Findings

We identified 26 studies examining cognitive outcomes associated with medical and recreational use of cannabis in healthy aging, dementia, Parkinson's disease, multiple sclerosis, HIV, and pain populations. Although variability in the cannabis products used, outcomes assessed, and study quality limits the conclusions that can be made, modest reductions in cognitive performance were generally detected with higher doses and heavier lifetime use.

Summary

This review highlights the need for additional high-quality research using standardized, validated assessments of cannabis exposure and cognitive outcomes. Reliable measures and longitudinal data are necessary to better characterize the effects of cannabis use on cognitive aging, as well as differential effects of recreational and medical cannabis.

Current Agents in Development for Treating Behavioral and Psychological Symptoms Associated with Dementia

Behavioral and psychological symptoms associated with dementia are highly prevalent and are associated with an increased risk of institutionalization and mortality. Current pharmacological treatments for these symptoms include cholinesterase inhibitors, antipsychotics, and selective serotonin reuptake inhibitors. When used for treating behavioral and psychological symptoms associated with dementia, they are associated with limited efficacy and/or serious adverse events. As such, there has been extensive research into novel agents with varying mechanisms of action targeting behavioral and psychological symptoms associated with dementia. In this article, we present the results of a comprehensive literature search and review that evaluates current agents that have completed or are currently in clinical trials for treating behavioral and psychological symptoms associated with dementia as a primary outcome. We highlight novel agents from miscellaneous drug classes, such as dextromethorphan/quinidine, bupropion/dextromethorphan, lumateperone, deudextromethorphan/quinidine, methylphenidate and scyllo-inositol, and drugs from various therapeutic classes (including atypical antipsychotics, selective serotonin reuptake inhibitors, and cannabinoids) that have demonstrated promising results and were generally well tolerated. Future research with large appropriately powered studies using validated outcome measures for behavioral and psychological symptoms associated with dementia should be conducted to further establish the clinical utility of these agents.

Safety and effectiveness of cannabinoids for the treatment of neuropsychiatric symptoms in dementia: a systematic review

Background:

Neuropsychiatric symptoms (NPS) in dementia impact profoundly on the quality of life of people living with dementia and their care givers. Evidence for the effectiveness and safety of current therapeutic options is varied. Cannabinoids have been proposed as an alternative therapy, mainly due to their activity on CB1 receptors in the central nervous system. However, little is known regarding the safety and effectiveness of cannabinoid therapy in people with dementia. A literature review was undertaken to identify, describe and critically appraise studies investigating cannabinoid use in treating NPS in dementia.

Methods:

We undertook a systematic review adhering to PRISMA guidelines. Twenty-seven online resources were searched, including Medline, PsycINFO and Embase. Studies assessing the safety and or effectiveness of cannabinoids in treating NPS in dementia in people aged ⩾ 65 years were included. Study quality was assessed using the Johanna Briggs Institute and Cochrane Collaboration critical appraisal tools.

Results:

Twelve studies met the inclusion criteria. There was considerable variability across the studies with respect to study design (50% randomized controlled trials), intervention [dronabinol (33%), nabilone (25%) or delta-9 tetrahydrocannabinol (THC; 42%)] and outcome measures. Dronabinol (three studies) and THC (one study) were associated with significant improvements in a range of neuropsychiatric scores. The most common adverse drug event (ADE) reported was sedation. A high risk of bias was found in eight studies. The highest-quality trial found no significant improvement in symptoms or difference in ADE rate between treatment arms. Included studies used low doses of oral cannabinoids and this may have contributed to the lack of demonstrated efficacy.

Conclusion:

While the efficacy of cannabinoids was not proven in a robust randomized control trial, observational studies showed promising results, especially for patients whose symptoms were refractory. In addition, the safety profile is favourable as most of the ADEs reported were mild. Future trials may want to consider dose escalation and formulations with improved bioavailability.

Cannabinoid Actions on Neural Stem Cells: Implications for Pathophysiology

With the increase of life expectancy, neurodegenerative disorders are becoming not only a health but also a social burden worldwide. However, due to the multitude of pathophysiological disease states, current treatments fail to meet the desired outcomes. Therefore, there is a need for new therapeutic strategies focusing on more integrated, personalized and effective approaches. The prospect of using neural stem cells (NSC) as regenerative therapies is very promising, however several issues still need to be addressed. In particular, the potential actions of pharmacological agents used to modulate NSC activity are highly relevant. With the ongoing discussion of cannabinoid usage for medical purposes and reports drawing attention to the effects of cannabinoids on NSC regulation, there is an enormous, and yet, uncovered potential for cannabinoids as treatment options for several neurological disorders, specifically when combined with stem cell therapy. In this manuscript, we review in detail how cannabinoids act as potent regulators of NSC biology and their potential to modulate several neurogenic features in the context of pathophysiology.

Comprehensive review of mechanisms of pathogenesis involved in Alzheimer's disease and potential therapeutic strategies

AD is a progressive neurodegenerative disorder and a leading cause of dementia in an aging population worldwide. The enormous challenge which AD possesses to global healthcare makes it as urgent as ever for the researchers to develop innovative treatment strategies to fight this disease. An in-depth analysis of the extensive available data associated with the AD is needed for a more comprehensive understanding of underlying molecular mechanisms and pathophysiological pathways associated with the onset and progression of the AD. The currently understood pathological and biochemical manifestations include cholinergic, Aβ, tau, excitotoxicity, oxidative stress, ApoE, CREB signaling pathways, insulin resistance, etc. However, these hypotheses have been criticized with several conflicting reports for their involvement in the disease progression. Several issues need to be addressed such as benefits to cost ratio with cholinesterase therapy, the dilemma of AChE selectivity over BChE, BBB permeability of peptidic BACE-1 inhibitors, hurdles related to the implementation of vaccination and immunization therapy, and clinical failure of candidates related to newly available targets. The present review provides an insight to the different molecular mechanisms involved in the development and progression of the AD and potential therapeutic strategies, enlightening perceptions into structural information of conventional and novel targets along with the successful applications of computational approaches for the design of target-specific inhibitors.

Cannabinoids for the treatment of neuropsychiatric symptoms, pain and weight loss in dementia

PURPOSE OF REVIEW

Efficacious treatment for neuropsychiatric symptoms (NPS), pain and weight loss for dementia patients is desperately needed. This review presents an up-to-date look at the literature investigating the use of cannabinoid for these symptoms in dementia.

RECENT FINDINGS

We searched electronically for publications regarding cannabinoid use in dementia, with a focus on Alzheimer's disease. Seven studies and one case report have been conducted to examine the use of cannabinoids for the treatment of NPS of dementia, and three of these trials reported on the effect of cannabinoids on weight. Five studies reported decreased agitation or improvements in sleep with cannabinoid use. One crossover trial found that cannabinoids positively impacted weight, whereas a chart review study found no impact on weight with cannabinoids, but an increase in food intake. There were no trials examining the use of cannabinoids for pain in dementia.

SUMMARY

Findings from trials with small sample sizes and various clinical populations suggest that cannabinoid use may be well tolerated and effective for treatment of NPS such as agitation as well as weight and pain management in patients with dementia. Additional studies are necessary to further elucidate the relative risks and benefits of this treatment.

Cannabinoid receptor 2 as a novel target for promotion of renal cell carcinoma prognosis and progression

PURPOSE

Renal cell carcinoma (RCC) is the most common malignancy of urogenital system, and patients with RCC may face a poor prognosis. However, limited curable therapeutic options are currently available. The aim of this study is to investigate the role of Cannabinoid receptor 2 (CB2) in RCC progression.

METHODS

Immunohistochemistry was to investigate the expression pattern of CB2 in 418 RCC tissues and explore its prognostic function in RCC patients. Furthermore, the role of used CB2 si-RNA knockdown and inhibited by AM630, a CB2 inverse agonist, on cell proliferation, migration, and cell cycle of RCC cell lines in vitro was also investigated.

RESULTS

We observed that CB2 was up-regulated in RCC tissues, and presented as an independent prognostic factor for overall survival of RCC patients and higher CB2 expression tends to have poor clinical outcomes in survival analyses. Moreover, we also observed that CB2, incorporated with pN stage, pathological grade, and recurrence or distant metastasis after surgery, could obviously enhance their prognostic accuracy in a predictive nomogram analysis. In addition, knockdown or inhibition by AM630 for the expression of CB2 in vitro could significantly decreased cell proliferation and migration, and obviously induced cell cycle arrest in G2/M of RCC cells.

CONCLUSIONS

CB2 expression is functionally related to cellular proliferation, migration, and cell cycle of RCC cells. Our data suggest that CB2 might be a potential therapeutic target for RCC.

Cannabinoid Receptors in the Central Nervous System: Their Signaling and Roles in Disease

The identification and cloning of the two major cannabinoid (CB₁ and CB₂) receptors together with the discovery of their endogenous ligands in the late 80s and early 90s, resulted in a major effort aimed at understanding the mechanisms and physiological roles of the endocannabinoid system (ECS). Due to its expression and localization in the central nervous system (CNS), the CB₁ receptor together with its endogenous ligands (endocannabinoids (eCB)) and the enzymes involved in their synthesis and degradation, has been implicated in multiple pathophysiological events ranging from memory deficits to neurodegenerative disorders among others. In this review, we will provide a general overview of the ECS with emphasis on the CB₁ receptor in health and disease. We will describe our current understanding of the complex aspects of receptor signaling and trafficking, including the non-canonical signaling pathways such as those mediated by β-arrestins within the context of functional selectivity and ligand bias. Finally, we will highlight some of the disorders in which CB₁ receptors have been implicated. Significant knowledge has been achieved over the last 30 years. However, much more research is still needed to fully understand the complex roles of the ECS, particularly in vivo and to unlock its true potential as a source of therapeutic targets.

From Phytocannabinoids to Cannabinoid Receptors and Endocannabinoids: Pleiotropic Physiological and Pathological Roles Through Complex Pharmacology

Apart from having been used and misused for at least four millennia for, among others, recreational and medicinal purposes, the cannabis plant and its most peculiar chemical components, the plant cannabinoids (phytocannabinoids), have the merit to have led humanity to discover one of the most intriguing and pleiotropic endogenous signaling systems, the endocannabinoid system (ECS). This review article aims to describe and critically discuss, in the most comprehensive possible manner, the multifaceted aspects of 1) the pharmacology and potential impact on mammalian physiology of all major phytocannabinoids, and not only of the most famous one Δ9-tetrahydrocannabinol, and 2) the adaptive pro-homeostatic physiological, or maladaptive pathological, roles of the ECS in mammalian cells, tissues, and organs. In doing so, we have respected the chronological order of the milestones of the millennial route from medicinal/recreational cannabis to the ECS and beyond, as it is now clear that some of the early steps in this long path, which were originally neglected, are becoming important again. The emerging picture is rather complex, but still supports the belief that more important discoveries on human physiology, and new therapies, might come in the future from new knowledge in this field.