The role of cannabis in treating anxiety: an update.

Image result for ovid journals “Cannabis use for medical purposes has become increasingly common, including as treatment for mental health disorders such as anxiety. Unfortunately, the evidence examining its use in mental health has been slow to evolve, but is emerging. Given the widespread use of cannabis, it is important for both clinicians and those who suffer with anxiety to understand the effects of cannabis on symptoms of anxiety. In this review, we present recent, available evidence from animal models, clinical trials, and survey studies and evaluate the contribution of these studies to the current understanding of the role of cannabis in treating anxiety.

RECENT FINDINGS:

In reviewing recent evidence, we observed significant inconsistencies across findings from preclinical studies. Large-scale surveys suggest that cannabis may be effective in reducing anxiety, however, these results stand in contrast to equivocal findings from clinical trials.

SUMMARY:

The literature evaluating the efficacy of cannabis in anxiety disorders is in its infancy. The survey data is generally positive. Although, while some animal studies posit cannabis constituents to have anxiolytic effects, others suggest the opposite or null results. Few new clinical trials have been conducted recently, and the extant trials have significant flaws in methodology. Although anecdotal evidence from survey studies, and a small signal found in animal studies and single-dose clinical trials provide early support that cannabis may be effective for alleviating anxiety, ultimately, the current evidence is equivocal. More high-quality clinical trials must be published before sound conclusions regarding the efficacy of cannabis for treating anxiety can be drawn.”

https://www.ncbi.nlm.nih.gov/pubmed/31688192

https://insights.ovid.com/crossref?an=00001504-900000000-99166

Structure of an allosteric modulator bound to the CB1 cannabinoid receptor.

Image result for nature chemical biology“The CB1 receptor mediates the central nervous system response to cannabinoids, and is a drug target for pain, anxiety and seizures.

CB1 also responds to allosteric modulators, which influence cannabinoid binding and efficacy.

To understand the mechanism of these compounds, we solved the crystal structure of CB1 with the negative allosteric modulator (NAM) ORG27569 and the agonist CP55940.

The structure reveals that the NAM binds to an extrahelical site within the inner leaflet of the membrane, which overlaps with a conserved site of cholesterol interaction in many G protein-coupled receptors (GPCRs).

The ternary structure with ORG27569 and CP55940 captures an intermediate state of the receptor, in which aromatic residues at the base of the agonist-binding pocket adopt an inactive conformation despite the large contraction of the orthosteric pocket.

The structure illustrates a potential strategy for drug modulation of CB1 and other class A GPCRs.”

https://www.ncbi.nlm.nih.gov/pubmed/31659318

https://www.nature.com/articles/s41589-019-0387-2

Cannabinoid receptor type 1 modulates the effects of polyunsaturated fatty acids on memory of stressed rats.

 Publication Cover“Memory and GABAergic activity in the hippocampus of stressed rats improve after n-3 polyunsaturated fatty acid (PUFA) supplementation.

On the other hand, cannabinoid receptor type 1 (CB1) strongly regulates inhibitory neurotransmission in the hippocampus. Speculation about a possible relation between stress, endocannabinoids, and PUFAs.

Here, we examined whether the effects of PUFAs on memory of chronically stressed rats depends on pharmacological manipulation of CB1 receptors.

Memory improved in the stressed rats that were treated with AM251 and/or n-3 PUFAs. Supplementation with n-6 PUFAs did not affect memory of stressed rats, but co-treatment with AM251 improved it, while co-treatment with WIN55,212-2 did not affect memory.

Our results demonstrate that activity of the CB1 receptors may modulate the effects of PUFAs on memory of stressed rats. This study suggests that endocannabinoids and PUFAs can both become a singular system by being self-regulated in limbic areas, so they control the effects of stress on the brain.”

https://www.ncbi.nlm.nih.gov/pubmed/31637966

https://www.tandfonline.com/doi/abs/10.1080/1028415X.2019.1659561?journalCode=ynns20

Neuropeptide Y and cannabinoids interaction in the amygdala after exposure to shock and reminders model of PTSD.

Neuropharmacology“Modulation of cannabinoid and neuropeptide Y (NPY) receptors may offer therapeutic benefits for post-traumatic stress disorder (PTSD).

In this study, we aimed to investigate the functional interaction between these systems in the basolateral amygdala (BLA) in a rat model of PTSD.

The findings suggest that the functional interaction between the eCB and NPY1 systems is complex and provide a rationale for exploring novel therapeutic strategies that target the cannabinoid and NPY systems for stress-related diseases.”

https://www.ncbi.nlm.nih.gov/pubmed/31622603

https://www.sciencedirect.com/science/article/pii/S0028390819303661?via%3Dihub

Modulation of the Endocannabinoid and Oxytocinergic Systems as a Potential Treatment Approach for Social Anxiety Disorder.

 “Social anxiety disorder (SAD), or social phobia, is one of the most common types of anxiety disorder, with a lifetime prevalence that can reach 15%.

Pharmacological treatments for SAD have moderate efficacy and are associated with significant adverse reactions. Therefore, recent studies have focused on searching for new treatments for this disorder.

Preclinical studies and preliminary evidence in humans suggest that the phytocannabinoid cannabidiol and the neuropeptide oxytocin have anxiolytic effects. In the present text, we review this evidence and its implications for pharmacological treatment.

We conclude that although current available studies show promising results regarding both the safety and efficacy of cannabidiol and oxytocin for the treatment of SAD, most studies were performed using single or few doses of these compounds, with small sample sizes.

Therefore, future studies should explore the anxiolytic potential of these compounds using long-term, placebo-controlled designs with larger samples to elucidate the possible use of these compounds in the treatment of SAD.”

https://www.ncbi.nlm.nih.gov/pubmed/31617149

https://link.springer.com/article/10.1007%2Fs40263-019-00669-5

Effects of cannabidiol (CBD) in neuropsychiatric disorders: A review of pre-clinical and clinical findings.

Progress in Molecular Biology and Translational Science“Cannabis sativa (cannabis) is one of the oldest plants cultivated by men. Cannabidiol (CBD) is the major non-psychomimetic compound derived from cannabis. It has been proposed to have a therapeutic potential over a wide range of neuropsychiatric disorders.

In this narrative review, we have summarized a selected number of pre-clinical and clinical studies, examining the effects of CBD in neuropsychiatric disorders. In some pre-clinical studies, CBD was demonstrated to potentially exhibit anti-epileptic, anti-oxidant, anti-inflammatory anti-psychotic, anxiolytic and anti-depressant properties. Moreover, CBD was shown to reduce addictive effects of some drugs of abuse.

In clinical studies, CBD was shown to be safe, well-tolerated and efficacious in mitigating the symptoms associated with several types of seizure disorders and childhood epilepsies.

Given that treatment with CBD alone was insufficient at managing choreic movements in patients with Huntington’s disease, other cannabis-derived treatments are currently being investigated. Patients with Parkinson’s disease (PD) have reported improvements in sleep and better quality of life with CBD; however, to fully elucidate the therapeutic potential of CBD on the symptoms of PD-associated movement disorders, larger scale, randomized, placebo-controlled studies still need to be conducted in the future.

Currently, there are no human studies that investigated the effects of CBD in either Alzheimer’s disease or unipolar depression, warranting further investigation in this area, considering that CBD was shown to have effects in pre-clinical studies.

Although, anxiolytic properties of CBD were reported in the Social Anxiety Disorder, antipsychotic effects in schizophrenia and anti-addictive qualities in alcohol and drug addictions, here too, larger, randomized, placebo-controlled trials are needed to evaluate the therapeutic potential of CBD.”

https://www.ncbi.nlm.nih.gov/pubmed/31601406

https://www.sciencedirect.com/science/article/pii/S187711731930095X?via%3Dihub

Stress and Western diets increase vulnerability to neuropsychiatric disorders: A common mechanism.

Publication Cover“In modern lifestyle, stress and Western diets are two major environmental risk factors involved in the etiology of neuropsychiatric disorders. Lifelong interactions between stress, Western diets, and how they can affect brain physiology, remain unknown.

A possible relation between dietary long chain polyunsaturated fatty acids (PUFA), endocannabinoids, and stress is proposed.

This review suggests that both Western diets and negative stress or distress increase n-6/n-3 PUFA ratio in the phospholipids of the plasma membrane in neurons, allowing an over-activation of the endocannabinoid system in the limbic areas that control emotions. As a consequence, an excitatory/inhibitory imbalance is induced, which may affect the ability to synchronize brain areas involved in the control of stress responses. These alterations increase vulnerability to neuropsychiatric disorders.

Accordingly, dietary intake of n-3 PUFA would counter the effects of stress on the brain of stressed subjects. In conclusion, this article proposes that PUFA, endocannabinoids, and stress form a unique system which is self-regulated in limbic areas which in turn controls the effects of stress on the brain throughout a lifetime.”

Preclinical and Clinical Evidence Supporting Use of Cannabidiol in Psychiatry.

Image result for hindawi “Cannabidiol (CBD) is a major chemical compound present in Cannabis sativa.

CBD is a nonpsychotomimetic substance, and it is considered one of the most promising candidates for the treatment of psychiatric disorders.

The aim of this review is to illustrate the state of art about scientific research and the evidence of effectiveness of CBD in psychiatric patients.

RESULTS:

Preclinical and clinical studies on potential role of CBD in psychiatry were collected and further discussed. We found four clinical studies describing the effects of CBD in psychiatric patients: two studies about schizophrenic patients and the other two studies carried out on CBD effects in patients affected by generalized social anxiety disorder (SAD).

CONCLUSION:

Results from these studies are promising and suggest that CBD may have a role in the development of new therapeutic strategies in mental diseases, and they justify an in-depth commitment in this field. However, clinical evidence we show for CBD in psychiatric patients is instead still poor and limited to schizophrenia and anxiety, and it needs to be implemented with further studies carried out on psychiatric patients.”

https://www.ncbi.nlm.nih.gov/pubmed/31558911

“Results of our research, enriched in assessment of methodological quality of the studies, confirm the view of this cannabinoid as a promising molecule especially in particular sectors of psychiatry such as schizophrenia, anxiety, depression, and autism. CBD is considered a safe substance and is one of the most promising candidates for the treatment of psychiatric disorders”.

https://www.hindawi.com/journals/ecam/2019/2509129/

The “entourage effect”: Terpenes coupled with cannabinoids for the treatment of mood disorders and anxiety disorders.

“Mood disorders are the most prevalent mental conditions encountered in psychiatric practice. Numerous patients suffering from mood disorders present with treatment-resistant forms of depression, co-morbid anxiety, other psychiatric disorders and bipolar disorders.

Standardized essential oils (such as that of Lavender officinalis) have been shown to exert clinical efficacy in treating anxiety disorders. As endocannabinoids are suggested to play an important role in major depression, generalized anxiety and bipolar disorders, Cannabis sativa, was suggested for their treatment.

The endocannabinoid system is widely distributed throughout the body including the brain, modulating many functions. It is involved in mood and related disorders, and its activity may be modified by exogenous cannabinoids.

CB1 and CB2 receptors primarily serve as the binding sites for endocannabinoids as well as for phytocannabinoids, produced by cannabis inflorescences. However, ‘cannabis’ is not a single compound product but is known for its complicated molecular profile, producing a plethora of phytocannabinoids alongside a vast array of terpenes.

Thus, the “entourage effect” is the suggested positive contribution derived from the addition of terpenes to cannabinoids. Here we review the literature on the effects of cannabinoids and discuss the possibility of enhancing cannabinoid activity on psychiatric symptoms by the addition of terpenes and terpenoids.

Possible underlying mechanisms for the anti-depressant and anxiolytic effects are reviewed. These natural products may be an important potential source for new medications for the treatment of mood and anxiety disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/31481004

http://www.eurekaselect.com/174648/article

A systematic review of cannabidiol dosing in clinical populations.

British Journal of Clinical Pharmacology banner“Cannabidiol is a cannabis-derived medicinal product with potential application in a wide-variety of contexts, however its effective dose in different disease states remains unclear. This review aimed to investigate what doses have been applied in clinical populations, in order to understand the active range of cannabidiol in a variety of medical contexts.

RESULTS:

A total of 1038 articles were retrieved, of which 35 studies met inclusion criteria covering 13 medical contexts. 23 studies reported a significant improvement in primary outcomes (e.g. psychotic symptoms, anxiety, seizures), with doses ranging between <1 – 50 mg/Kg/day. Plasma concentrations were not provided in any publication. Cannabidiol was reported as well tolerated and epilepsy was the most frequently studied medical condition, with all 11 studies demonstrating positive effects of cannabidiol on reducing seizure frequency or severity (average 15 mg/Kg/day within randomised controlled trials). There was no signal of positive activity of CBD in small randomised controlled trials (range n=6-62) assessing diabetes, Crohn’s disease, ocular hypertension, fatty liver disease or chronic pain. However, low doses (average 2.4 mg/Kg/day) were used in these studies.

CONCLUSION:

This review highlights cannabidiol has a potential wide range of activity in several pathologies. Pharmacokinetic studies as well as conclusive phase III trials to elucidate effective plasma concentrations within medical contexts are severely lacking and highly encouraged.”

https://www.ncbi.nlm.nih.gov/pubmed/31222854

https://bpspubs.onlinelibrary.wiley.com/doi/abs/10.1111/bcp.14038