Cannabinoids for Behavioral Symptoms in Dementia: An Overview

pubmed logo

“Dementia, with loss of memory, cognitive abilities, and independent daily functioning, is increasing worldwide, related to an aging population. Currently, there is no curative treatment for dementia. Treatment of the frequently occurring behavioral and psychological symptoms of dementia (BPSD) is partially effective and associated with significant side effects.

Cannabinoids are lipophilic molecules acting on the CB1 end CB2 receptors, essential for main biological processes such as sleep, appetite, memory, and pain. Cannabinoids might have a positive impact on amyloid formation in Alzheimer’s disease, the main form of dementia, and on BPSD symptoms. Most knowledge currently concerns delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD).

In the context of dementia and BPSD, THC might be beneficial for associated spasticity and possible pain or lack of appetite and CBD probably works better on sleep, agitation, and anxiety. This overview of prospective clinical studies and randomized clinical trials, published between 2005 and April 2023, using cannabinoids for BPSD suggests that older studies using low-dose oral synthetic THC showed no positive results.

Still, more recent studies using THC/CBD-based oral medication at higher doses show promising results and are feasible and safe in this elderly polymedicated population. Several RCTs are ongoing and planned worldwide, and we hope other trials will follow to establish clinical efficiency and optimal dosing, as well as other outcomes such as deprescribing other medications and facilitation of care. We suggest that researchers also address the more sociological aspects of prescribing cannabinoids for dementia and BPSD in their specific context.”

https://pubmed.ncbi.nlm.nih.gov/38447959/

https://www.thieme-connect.de/products/ejournals/abstract/10.1055/a-2262-7837

Cannabidiol improves memory and decreases IL-1β serum levels in rats with lipopolysaccharide-induced inflammation

pubmed logo

“Memory improving and anti-inflammatory properties of cannabidiol (CBD) were investigated in an experimental model of lipopolysaccharide (LPS)-induced inflammation.”

https://pubmed.ncbi.nlm.nih.gov/38351784/

“Cannabis sativa is a plant that has been cultivated by humans and utilized in medicine since ancient times.”

“Cannabidiol (CBD) is one of the most important Cannabis-derived molecules,”

“CBD improved spatial working and recognition memory in rats with LPS-induced inflammation. Suppression of IL-1β production could be attributed to the observed effect.”

https://foliamedica.bg/article/107259/

Identification of Anti-Neuroinflammatory Bioactive Compounds in Essential Oils and Aqueous Distillation Residues Obtained from Commercial Varieties of Cannabis sativa L

pubmed logo

“Neuroinflammation, which is mainly triggered by microglia, is a key contributor to multiple neurodegenerative diseases.

Natural products, and in particular Cannabis sativa L., due to its richness in phytochemical components, represent ideal candidates to counteract neuroinflammation.

We previously characterized different C. sativa commercial varieties which showed significantly different chemical profiles. On these bases, the aim of this study was to evaluate essential oils and aqueous distillation residues from the inflorescences of three different hemp varieties for their anti-neuroinflammatory activity in BV-2 microglial cells. Cells were pretreated with aqueous residues or essential oils and then activated with LPS. Unlike essential oils, aqueous residues showed negligible effects in terms of anti-inflammatory activity. Among the essential oils, the one obtained from ‘Gorilla Glue’ was the most effective in inhibiting pro-inflammatory mediators and in upregulating anti-inflammatory ones through the modulation of the p38 MAPK/NF-κB pathway. Moreover, the sesquiterpenes (E)-caryophyllene, α-humulene, and caryophyllene oxide were identified as the main contributors to the essential oils’ anti-inflammatory activity. To our knowledge, the anti-neuroinflammatory activity of α-humulene has not been previously described.

In conclusion, our work shows that C. sativa essential oils characterized by high levels of sesquiterpenes can be promising candidates in the prevention/counteraction of neuroinflammation.”

https://pubmed.ncbi.nlm.nih.gov/38068924/

https://www.mdpi.com/1422-0067/24/23/16601

Characterizing cannabis-prevalent terpenes for neuroprotection reveal a role for α and β-pinenes in mitigating amyloid β-evoked neurotoxicity and aggregation in vitro

pubmed logo

Background: Cannabis Sativa L. (C. sativa) can efficiently synthesize of over 200 terpenes, including monoterpenes, sesquiterpenes and triterpenes that may contribute to the known biological activities of phytocannabinoids of relevance for the burgeoning access to medicinal cannabis formulations globally; however, to date have been uncharacterized. We assessed twelve predominant terpenes in C. sativa for neuroprotective and anti-aggregative properties in semi-differentiated PC12 neuronal cell line that is robust and validated as a cell model responsive to amyloid β (Aβ1-42) protein exposure and oxidative stress.

Methods: Cell viability was assessed biochemically using the MTT assay in the presence of myrcene, β-caryophyllene, terpinolene, limonene, linalool, humulene, α-pinene, nerolidol, β-pinene, terpineol, citronellol and friedelin (1-200μM) for 24hr. Sub-toxic threshold test concentrations of each terpene were then applied to cells, alone or with concomitant incubation with the lipid peroxidant tert-butyl hyrdroperoxide (t-BHP; 0-250μM) or amyloid β (Aβ1-42; 0-1μM) to assess neuroprotective effects. Direct effects of each terpene on Aβ fibril formation and aggregation were also evaluated using the Thioflavin T (ThT) fluorometric kinetic assay and transmission electron microscopy (TEM) to visualize fibril and aggregate morphology

Results: Terpenes were intrinsically benign to PC12 cells up to 50μM, with higher concentrations of β-caryophyllene, humulene and nerolidol inducing some loss of PC12 cell viability. No significant protective effects of terpenes were observed following t-BHP (0-200µM) administration, with some enhanced toxicity instead demonstrated from both β-caryophyllene and humulene treatment (each at 50µM). α-pinene and β-pinene demonstrated a significant neuroprotective effect against amyloid β exposure. α-pinene, β-pinene, terpineol, terpinolene and friedelin were associated with a variable inhibition of Aβ1-42 fibril and aggregate density.

Conclusions: The outcomes of this study underline a neuroprotective role of α-pinene and β-pinene against Aβ-mediated neurotoxicity associated with an inhibition of Aβ1-42 fibrilization and density. This demonstrates the bioactive potential of selected terpenes for consideration in the development of medicinal cannabis formulations targeting neurodegenerative diseases.”

https://pubmed.ncbi.nlm.nih.gov/38070653/

“In summary, the outcomes from this study reveal a novel and efficacious neuroprotective and anti-aggregatory effect of α-pinene and β-pinene against β amyloid-mediated toxicity. The modest inhibition of lipid peroxidation from α-pinene, β-pinene, and terpinolene may also contribute to the multifaceted neuroprotection of C. sativa-prevalent terpenes. In addition, limited anti-aggregatory effects were observed from terpineol, terpinolene, α-pinene, β-pinene and friedelin. The outcomes of this study contribute to an emerging body of knowledge towards the potential synergistic bioactivities of selected terpenes for consideration in the development of medicinal cannabis formulations targeting neurodegenerative diseases.”

https://www.sciencedirect.com/science/article/pii/S0161813X23001699?via%3Dihub

The Use of Dispensary-Obtained Tetrahydrocannabinol as a Treatment for Neuropsychiatric Symptoms of Dementia

pubmed logo

“Objective: Neuropsychiatric symptoms (NPS) of dementia represent a large driver of health care costs, caregiver burden, and institutionalization of people with dementia. Management options are limited, and antipsychotics are often used, although they carry a significant side effect profile. One novel option is tetrahydrocannabinol (THC); however, in the US, to obtain THC for patients with dementia, caregivers have to go to a commercial dispensary. We evaluated the effectiveness of dispensary-obtained THC for patients with dementia and NPS.

Methods: Two independent reviewers reviewed charts of patients with diagnosed dementia (N = 50) seen in geriatric psychiatry between 2017 and 2021 for whom dispensary-obtained THC was recommended. The primary outcome was effectiveness in treating NPS; secondary outcomes were the proportion of caregivers who obtained and administered THC (uptake), post-THC antipsychotic use, and adverse reactions leading to treatment discontinuation.

Results: Caregiver uptake of dispensary-obtained THC was high (38/50, 76%). The majority of patients (30/38, 79%) who took THC had an improvement in NPS according to their caregivers. THC was recommended most often for the NPS of agitation, aggression, irritability, lability, anxiety, and insomnia. Among the 20 patients who were taking antipsychotics at baseline and took THC, over half (12/20, 60%) were able to decrease or discontinue the antipsychotic. Adverse reactions to THC included dizziness, worsening of agitation, and worsening of paranoia; two caregivers of patients who took THC reported adverse reactions that led to treatment discontinuation.

Conclusions: Our results suggest that dispensary-obtained THC can be effective in managing a subset of NPS in patients with dementia and may decrease the requirement for antipsychotics.”

https://pubmed.ncbi.nlm.nih.gov/37728481/

https://www.psychiatrist.com/jcp/neurologic/dementia/dispensary-obtained-tetrahydrocannabinol-treatment-neuropsychiatric-symptoms-dementia/

Cannabis reduces anxiety in dementia

MMW - Advances in Medicine 14/2023

“Neuropsychiatric symptoms occur in almost 90% of people with dementia. Agitated and aggressive behavior significantly reduces the quality of life of those affected and those around them, but it is difficult to access therapy. One option could be medicinal cannabis. The results of a double-blind, placebo-controlled study indicate that a full-spectrum cannabis extract with a high content of cannabidiol (CBD) can reduce dementia-related agitation [1]. In the study, 60 patients with severe neurocognitive disorder and associated behavioral disorders received a full-spectrum cannabis extract with 1% tetrahydrocannabinol (THC) and 30% CBD (Re:cannis) or a placebo oil. After 16 weeks, sleep disturbances, Agitation and aggression significantly improved compared to the placebo group. Since the effects only became apparent in the 14th week, patience is required.”

https://www.springermedizin.de/agitiertheit/demenz/cannabis-daempft-die-unruhe-bei-demenz/25883850?fulltextView=true&doi=10.1007%2Fs15006-023-2867-2

Hippocampal differential expression underlying the neuroprotective effect of delta-9-tetrahydrocannabinol microdose on old mice

pubmed logo

“Delta-9-tetrahydrocannabinol (THC) is the primary psychoactive compound of the cannabis plant and an exogenous ligand of the endocannabinoid system. In previous studies, we demonstrated that a single microdose of THC (0.002 mg/kg, 3-4 orders of magnitude lower than the standard dose for rodents) exerts distinct, long-term neuroprotection in model mice subjected to acute neurological insults. When administered to old, healthy mice, the THC microdose induced remarkable long-lasting (weeks) improvement in a wide range of cognitive functions, including significant morphological and biochemical brain alterations. To elucidate the mechanisms underlying these effects, we analyzed the gene expression of hippocampal samples from the model mice. Samples taken 5 days after THC treatment showed significant differential expression of genes associated with neurogenesis and brain development. In samples taken 5 weeks after treatment, the transcriptional signature was shifted to that of neuronal differentiation and survival. This study demonstrated the use of hippocampal transcriptome profiling in uncovering the molecular basis of the atypical, anti-aging effects of THC microdose treatment in old mice.”

https://pubmed.ncbi.nlm.nih.gov/37534036/

“Our findings imply that the THC microdose treatment alleviates age-dependent cognitive deficits by modulating multiple hallmarks of brain aging, supporting past hypotheses regarding the relation between aging and the endocannabinoid system.”

https://www.frontiersin.org/articles/10.3389/fnins.2023.1182932/full

The role of cannabidiol in aging

pubmed logo

“Aging is usually considered a key risk factor associated with multiple diseases, such as neurodegenerative diseases, cardiovascular diseases and cancer. Furthermore, the burden of age-related diseases has become a global challenge. It is of great significance to search for drugs to extend lifespan and healthspan. Cannabidiol (CBD), a natural nontoxic phytocannabinoid, has been regarded as a potential candidate drug for antiaging. An increasing number of studies have suggested that CBD could benefit healthy longevity. Herein, we summarized the effect of CBD on aging and analyzed the possible mechanism. All these conclusions may provide a perspective for further study of CBD on aging.”

https://pubmed.ncbi.nlm.nih.gov/37418976/

“CBD is a potential antiaging candidate. CBD possesses antioxidant, anti-inflammatory and autophagy-inducing properties. CBD has potentially beneficial therapeutic effects for several age-related diseases.”

https://www.sciencedirect.com/science/article/pii/S075333222300865X?via%3Dihub


Examining the use of cannabidiol and delta-9-tetrahydrocannabinol-based medicine among individuals diagnosed with dementia living within residential aged care facilities: Results of a double-blind randomised crossover trial

pubmed logo

“Objective: Dementia affects individuals older than 65 years. Currently, residential aged care facilities (RACF) use psychotropic medications to manage behavioural and neuropsychiatric symptoms of dementia (BPSD), which are recommended for short-term use and have substantial side effects, including increased mortality. Cannabinoid-based medicines (CBM) have some benefits that inhibit BPSD and cause minimal adverse effects (AEs), yet limited research has been considered with this population. The study aimed to determine a tolerable CBM dose (3:2 delta-9-tetrahydrocannabinol:cannabidiol), and assessed its effect on BPSD, quality of life (QoL) and perceived pain.

Methods: An 18-week randomised, double-blinded, crossover trial was conducted. Four surveys, collected on seven occasions, were used to measure changes in BPSD, QoL and pain. Qualitative data helped to understand attitudes towards CBM. General linear mixed models were used in the analysis, and the qualitative data were synthesised.

Results: Twenty-one participants (77% female participants, mean age 85) took part in the trial. No significant differences were seen between the placebo and CBM for behaviour, QOL or pain, except a decrease in agitation at the end of treatment in favour of CBM. The qualitative findings suggested improved relaxation and sleep among some individuals. Post hoc estimates on the data collected suggested that 50 cases would draw stronger conclusions on the Neuropsychiatric Inventory.

Conclusions: The study design was robust, rigorous and informed by RACF. The medication appeared safe, with minimal AEs experienced with CBM. Further studies incorporating larger samples when considering CBM would allow researchers to investigate the sensitivity of detecting BPSD changes within the complexity of the disease and concomitant with medications.”

https://pubmed.ncbi.nlm.nih.gov/37321847/

https://onlinelibrary.wiley.com/doi/10.1111/ajag.13224

Regulatory role of the endocannabinoid system on glial cells toward cognitive function in Alzheimer’s disease: A systematic review and meta-analysis of animal studies

Frontiers - Crunchbase Company Profile & Funding

“Objective: Over the last decade, researchers have sought to develop novel medications against dementia. One potential agent under investigation is cannabinoids. This review systematically appraised and meta-analyzed published pre-clinical research on the mechanism of endocannabinoid system modulation in glial cells and their effects on cognitive function in animal models of Alzheimer’s disease (AD). 

Methods: A systematic review complying with PRISMA guidelines was conducted. Six databases were searched: EBSCOHost, Scopus, PubMed, CINAHL, Cochrane, and Web of Science, using the keywords AD, cannabinoid, glial cells, and cognition. The methodological quality of each selected pre-clinical study was evaluated using the SYRCLE risk of bias tool. A random-effects model was applied to analyze the data and calculate the effect size, while I2 and p-values were used to assess heterogeneity. 

Results: The analysis included 26 original articles describing (1050 rodents) with AD-like symptoms. Rodents treated with cannabinoid agonists showed significant reductions in escape latency (standard mean difference [SMD] = -1.26; 95% confidence interval [CI]: -1.77 to -0.76, p < 0.00001) and ability to discriminate novel objects (SMD = 1.40; 95% CI: 1.04 to 1.76, p < 0.00001) compared to the control group. Furthermore, a significant decrease in Aβ plaques (SMD = -0.91; 95% CI: -1.55 to -0.27, p = 0.006) was observed in the endocannabinoid-treated group compared to the control group. Trends were observed toward neuroprotection, as represented by decreased levels of glial cell markers including glial fibrillary acid protein (SMD = -1.47; 95% CI: -2.56 to -0.38, p = 0.008) and Iba1 (SMD = -1.67; 95% CI: -2.56 to -0.79, p = 0.0002). Studies on the wild-type mice demonstrated significantly decreased levels of pro-inflammatory markers TNF-α, IL-1, and IL-6 (SMD = -2.28; 95% CI: -3.15 to -1.41, p = 0.00001). Despite the non-significant decrease in pro-inflammatory marker levels in transgenic mice (SMD = -0.47; 95% CI: -1.03 to 0.08, p = 0.09), the result favored the endocannabinoid-treated group over the control group. 

Conclusion: The revised data suggested that endocannabinoid stimulation promotes cognitive function via modulation of glial cells by decreasing pro-inflammatory markers in AD-like rodent models. Thus, cannabinoid agents may be required to modulate the downstream chain of effect to enhance cognitive stability against concurrent neuroinflammation in AD. Population-based studies and well-designed clinical trials are required to characterize the acceptability and real-world effectiveness of cannabinoid agents.”

https://pubmed.ncbi.nlm.nih.gov/36959856/

“Numerous traditional medical applications of cannabis have already been established and are now accepted practices in medicine.”

https://www.frontiersin.org/articles/10.3389/fphar.2023.1053680/full