The antidepressant and anxiolytic effects of cannabinoids in chronic unpredictable stress: a preclinical systematic review and meta-analysis

Translational Psychiatry

“Neuroscience research presents contradictory evidence in support of both the protective and destructive effects of cannabinoids in depression. Therefore, this systematic review and meta-analysis summarizes the existing preclinical literature on the effects of cannabinoid administration in the chronic unpredictable stress model of depression in order to evaluate the effects of cannabinoids and identify gaps in the literature. After protocol registration (PROSPERO #CRD42020219986), we systematically searched Scopus, Embase, Psychology & Behavioral Sciences Collection, APA PsychINFO, PubMed, CINAHL Complete, and ProQuest Dissertations & Theses Global from the earliest record of the databases, February 1964, to November 2020 for articles that met inclusion criteria (e.g., rodent subjects and administration of a cannabinoid. A total of 26 articles were included representing a sample size estimate of 1132 rodents with the majority of articles administering daily intraperitoneal injections during chronic unpredictable stress. These articles were evaluated using a modified SYRCLE’s risk-of-bias tool. For each continuous behavioral measure, the standardized mean difference was calculated between cannabinoid and vehicle groups in rodents subjected to chronic unpredictable stress. The effects of cannabinoids on depressive-like behavior was evaluated using a multilevel mixed-effects model with effect size weights nested within control groups. Cannabinoid administration moderately improved the pooled negative effects of chronic unpredictable stress on anhedonia, learned helplessness, novelty suppressed feeding, time in the anxiogenic context, and entries into the anxiogenic context. Although the interpretations are limited, these findings suggest that with further investigation, cannabinoids may be a viable long-term treatment for stress-related psychopathologies such as depression.”

https://pubmed.ncbi.nlm.nih.gov/35641487/

https://www.nature.com/articles/s41398-022-01967-1


Modulation of Endocannabinoid System Components in Depression: Pre-Clinical and Clinical Evidence

ijms-logo

“Depression is characterized by continuous low mood and loss of interest or pleasure in enjoyable activities. First-line medications for mood disorders mostly target the monoaminergic system; however, many patients do not find relief with these medications, and those who do suffer from negative side effects and a discouragingly low rate of remission.

Studies suggest that the endocannabinoid system (ECS) may be involved in the etiology of depression and that targeting the ECS has the potential to alleviate depression.

ECS components (such as receptors, endocannabinoid ligands, and degrading enzymes) are key neuromodulators in motivation and cognition as well as in the regulation of stress and emotions. Studies in depressed patients and in animal models for depression have reported deficits in ECS components, which is motivating researchers to identify potential diagnostic and therapeutic biomarkers within the ECS. By understanding the effects of cannabinoids on ECS components in depression, we enhance our understanding of which brain targets they hit, what biological processes they alter, and eventually how to use this information to design better therapeutic options.

In this article, we discuss the literature on the effects of cannabinoids on ECS components of specific depression-like behaviors and phenotypes in rodents and then describe the findings in depressed patients. A better understanding of the effects of cannabinoids on ECS components in depression may direct future research efforts to enhance diagnosis and treatment.”

https://pubmed.ncbi.nlm.nih.gov/35628337/

https://www.mdpi.com/1422-0067/23/10/5526

Medical cannabis use in Canada and its impact on anxiety and depression: A retrospective study

Psychiatry Research

“This was a retrospective study of patients utilizing medical cannabis who received their medical cannabis documentation and allotment from a Harvest Medicine clinic in Canada to determine the impact of medical cannabis on anxiety and depression outcomes. Patients included in the study were at least 18 years of age with completed validated questionnaires for anxiety (GAD-7) and depression (PHQ-9) at their initial evaluation and at least one follow-up visit. There were 7,362 patients included in the sample, of which the average age was 49.8 years, and 53.1% were female.

There were statistically significant improvements between baseline and follow-up scores for both the GAD-7 and PHQ-9, with larger improvements seen for patients who were actively seeking medical cannabis to treat anxiety or depression. From 12 months on, those reporting anxiety had an average decrease in GAD-7 scores that was greater than the minimum clinically important difference of 4, and the same was seen for patients reporting depression from 18 months on, with the average decrease in PHQ-9 scores more than the MCID minimum clinically important difference of 5. This study provides some evidence to support the effectiveness of medical cannabis as a treatment for anxiety and depression.”

https://pubmed.ncbi.nlm.nih.gov/35598566/

https://www.sciencedirect.com/science/article/abs/pii/S0165178122001834?via%3Dihub

Role and Function of Endocannabinoid System in Major Depressive Disease

“The endocannabinoid system (ECS) is a neuromodulator system with a crucial role in CNS and the reaction to endogenous and exogenous compounds and inflammation. Cannabidiol (CBD) is a basic part of the ECS which is the overwhelming causative and/or protective factor of major depressive disease (MDD). CBD interacts with brain-derived neurotropic factor (BDNF) that responds to inflammation, dysregulations of the hypothalamic-pituitary-adrenal (HPA) axis, and many more imbalances in MDD patients for which the ECS is a vital part to analyze, diagnose, and reflect the treatment. The ECS and MDD appear to have strong connections and interactions, so interest in ECS and CBD use in MDD patients is developing as a rescue resort.”

https://pubmed.ncbi.nlm.nih.gov/34676346/

An investigation of cannabis use for insomnia in depression and anxiety in a naturalistic sample

“Background: Little is known about cannabis use for insomnia in individuals with depression, anxiety, and comorbid depression and anxiety. To develop a better understanding of distinct profiles of cannabis use for insomnia management, a retrospective cohort study was conducted on a large naturalistic sample.

Methods: Data were collected using the medicinal cannabis tracking app, Strainprint®, which allows users to monitor and track cannabis use for therapeutic purposes. The current study examined users managing insomnia symptoms in depression (n = 100), anxiety (n = 463), and comorbid depression and anxiety (n = 114), for a total of 8476 recorded sessions. Inferential analyses used linear mixed effects modeling to examine self-perceived improvement across demographic variables and cannabis product variables.

Results: Overall, cannabis was perceived to be efficacious across all groups, regardless of age and gender. Dried flower and oral oil were reported as the most used and most efficacious product forms. In the depression group, all strains were perceived to be efficacious and comparisons between strains revealed indica-dominant (Mdiff = 1.81, 95% CI 1.26-2.36, Padj < .001), indica hybrid (Mdiff = 1.34, 95% CI 0.46-2.22, Padj = .045), and sativa-dominant (Mdiff = 1.83, 95% CI 0.68-2.99, Padj = .028) strains were significantly more efficacious than CBD-dominant strains. In anxiety and comorbid conditions, all strain categories were perceived to be efficacious with no significant differences between strains.

Conclusions: In terms of perceptions, individuals with depression, anxiety, and both conditions who use cannabis for insomnia report significant improvements in symptom severity after cannabis use. The current study highlights the need for placebo-controlled trials investigating symptom improvement and the safety of cannabinoids for sleep in individuals with mood and anxiety disorders.”

https://pubmed.ncbi.nlm.nih.gov/35484520/

Rapid treatments for depression: Endocannabinoid system as a therapeutic target

“Current first-line treatments for major depressive disorder (MDD), i.e., antidepressant drugs and psychotherapy, show delayed onset of therapeutic effect as late as 2-3 weeks or more. In the clinic, the speed of beginning of the actions of antidepressant drugs or other interventions is vital for many reasons. Late-onset means that depression, its related disability, and the potential danger of suicide remain a threat for some patients. There are some rapid-acting antidepressant interventions, such as sleep deprivation, ketamine, acute exercise, which induce a significant response, ranging from a few hours to maximally one week, and most of them share a common characteristic that is the activation of the endocannabinoid (eCB) system. Activation of this system, i.e., augmentation of eCB signaling, appears to have anti-depressant-like actions. This article puts the idea forward that the activation of eCB signaling represents a critical mechanism of rapid-acting therapeutic interventions in MDD, and this system might contribute to the development of novel rapid-acting treatments for MDD.”

https://pubmed.ncbi.nlm.nih.gov/35351488/

Cannabidiol prevents depressive-like behaviors through the modulation of neural stem cell differentiation

“Chronic stress impairs radial neural stem cell (rNSC) differentiation and adult hippocampal neurogenesis (AHN), whereas promoting AHN can increase stress resilience against depression. Therefore, investigating the mechanism of neural differentiation and AHN is of great importance for developing antidepressant drugs. The nonpsychoactive phytocannabinoid cannabidiol (CBD) has been shown to be effective against depression. However, whether CBD can modulate rNSC differentiation and hippocampal neurogenesis is unknown. Here, by using the chronic restraint stress (CRS) mouse model, we showed that hippocampal rNSCs mostly differentiated into astrocytes under stress conditions. Moreover, transcriptome analysis revealed that the FoxO signaling pathway was involved in the regulation of this process. The administration of CBD rescued depressive-like symptoms in CRS mice and prevented rNSCs overactivation and differentiation into astrocyte, which was partly mediated by the modulation of the FoxO signaling pathway. These results revealed a previously unknown neural mechanism for neural differentiation and AHN in depression and provided mechanistic insights into the antidepressive effects of CBD.”

https://pubmed.ncbi.nlm.nih.gov/35212887/

Antidepressant and Anxiolytic Effects of Medicinal Cannabis Use in an Observational Trial

Archive of &quot;Frontiers in Psychiatry&quot;.“Anxiety and depressive disorders are highly prevalent. Patients are increasingly using medicinal cannabis products to treat these disorders, but little is known about the effects of medicinal cannabis use on symptoms of anxiety and depression.

The aim of the present observational study was to assess general health in medicinal cannabis users and non-using controls with anxiety and/or depression. 

Results: Medicinal cannabis use was associated with lower self-reported depression, but not anxiety, at baseline. Medicinal cannabis users also reported superior sleep, quality of life, and less pain on average. Initiation of medicinal cannabis during the follow-up period was associated with significantly decreased anxiety and depressive symptoms, an effect that was not observed in Controls that never initiated cannabis use. 

Conclusions: Medicinal cannabis use may reduce anxiety and depressive symptoms in clinically anxious and depressed populations. Future placebo-controlled studies are necessary to replicate these findings and to determine the route of administration, dose, and product formulation characteristics to optimize clinical outcomes.”

https://pubmed.ncbi.nlm.nih.gov/34566726/

https://www.frontiersin.org/articles/10.3389/fpsyt.2021.729800/full

“Johns Hopkins: New Study Backs Claims That Cannabis Can Reduce Anxiety And Depression”  https://finance.yahoo.com/news/johns-hopkins-study-backs-claims-145005658.html

“Report Shows Cannabis is Effective in Treating Anxiety, Depression”   https://www.legalreader.com/report-shows-cannabis-is-effective-in-treating-anxiety-depression/

The Endocannabinoid System: A Potential Target for the Treatment of Various Diseases

ijms-logo“The Endocannabinoid System (ECS) is primarily responsible for maintaining homeostasis, a balance in internal environment (temperature, mood, and immune system) and energy input and output in living, biological systems.

In addition to regulating physiological processes, the ECS directly influences anxiety, feeding behaviour/appetite, emotional behaviour, depression, nervous functions, neurogenesis, neuroprotection, reward, cognition, learning, memory, pain sensation, fertility, pregnancy, and pre-and post-natal development.

The ECS is also involved in several pathophysiological diseases such as cancer, cardiovascular diseases, and neurodegenerative diseases. In recent years, genetic and pharmacological manipulation of the ECS has gained significant interest in medicine, research, and drug discovery and development.

The distribution of the components of the ECS system throughout the body, and the physiological/pathophysiological role of the ECS-signalling pathways in many diseases, all offer promising opportunities for the development of novel cannabinergic, cannabimimetic, and cannabinoid-based therapeutic drugs that genetically or pharmacologically modulate the ECS via inhibition of metabolic pathways and/or agonism or antagonism of the receptors of the ECS. This modulation results in the differential expression/activity of the components of the ECS that may be beneficial in the treatment of a number of diseases.

This manuscript in-depth review will investigate the potential of the ECS in the treatment of various diseases, and to put forth the suggestion that many of these secondary metabolites of Cannabis sativa L. (hereafter referred to as “C. sativa L.” or “medical cannabis”), may also have potential as lead compounds in the development of cannabinoid-based pharmaceuticals for a variety of diseases.”

https://pubmed.ncbi.nlm.nih.gov/34502379/

https://www.mdpi.com/1422-0067/22/17/9472

Efficacy and Safety of Cannabidiol Plus Standard Care vs Standard Care Alone for the Treatment of Emotional Exhaustion and Burnout Among Frontline Health Care Workers During the COVID-19 Pandemic: A Randomized Clinical Trial

Free Download JAMA Network Logo Vector from Tukuz.Com“Importance: Frontline health care professionals who work with patients with COVID-19 have an increased incidence of burnout symptoms. Cannabidiol (CBD) has anxiolytic and antidepressant properties and may be capable of reducing emotional exhaustion and burnout symptoms.

Objective: To investigate the safety and efficacy of CBD therapy for the reduction of emotional exhaustion and burnout symptoms among frontline health care professionals working with patients with COVID-19.

Interventions: Cannabidiol, 300 mg (150 mg twice per day), plus standard care or standard care alone for 28 days.

Main outcomes and measures: The primary outcome was emotional exhaustion and burnout symptoms, which were assessed for 28 days using the emotional exhaustion subscale of the Brazilian version of the Maslach Burnout Inventory-Human Services Survey for Medical Personnel.

Results: A total of 120 participants were randomized to receive either CBD, 300 mg, plus standard care (treatment arm; n = 61) or standard care alone (control arm; n = 59) for 28 days. Of those, 118 participants (59 participants in each arm; 79 women [66.9%]; mean age, 33.6 years [95% CI, 32.3-34.9 years]) received the intervention and were included in the efficacy analysis. In the treatment arm, scores on the emotional exhaustion subscale of the Maslach Burnout Inventory significantly decreased at day 14 (mean difference, 4.14 points; 95% CI, 1.47-6.80 points; partial eta squared [ηp2] = 0.08), day 21 (mean difference, 4.34 points; 95% CI, 0.94-7.73 points; ηp2 = 0.05), and day 28 (mean difference, 4.01 points; 95% CI, 0.43-7.59 points; ηp2 = 0.04). However, 5 participants, all of whom were in the treatment group, experienced serious adverse events: 4 cases of elevated liver enzymes (1 critical and 3 mild, with the mild elevations reported at the final 28-day assessment) and 1 case of severe pharmacodermia. In 2 of those cases (1 with critical elevation of liver enzymes and 1 with severe pharmacodermia), CBD therapy was discontinued, and the participants had a full recovery.

Conclusions and relevance: In this study, CBD therapy reduced symptoms of burnout and emotional exhaustion among health care professionals working with patients during the COVID-19 pandemic. However, it is necessary to balance the benefits of CBD therapy with potential undesired or adverse effects. Future double-blind placebo-controlled clinical trials are needed to confirm the present findings.”

https://pubmed.ncbi.nlm.nih.gov/34387679/

“Daily administration of CBD, 300 mg, combined with standard care reduced the symptoms and diagnoses of anxiety, depression, and emotional exhaustion among frontline health care professionals working with patients with COVID-19. Cannabidiol may act as an effective agent for the reduction of burnout symptoms among a population with important mental health needs worldwide.”

https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2782994