Can Physical Activity Support the Endocannabinoid System in the Preventive and Therapeutic Approach to Neurological Disorders?

ijms-logo“The worldwide prevalence of neurological and neurodegenerative disorders, such as depression or Alzheimer’s disease, has spread extensively throughout the last decades, becoming an enormous health issue.

Numerous data indicate a distinct correlation between the altered endocannabinoid signaling and different aspects of brain physiology, such as memory or neurogenesis. Moreover, the endocannabinoid system is widely regarded as a crucial factor in the development of neuropathologies. Thus, targeting those disorders via synthetic cannabinoids, as well as phytocannabinoids, becomes a widespread research issue.

Over the last decade, the endocannabinoid system has been extensively studied for its correlation with physical activity. Recent data showed that physical activity correlates with elevated endocannabinoid serum concentrations and increased cannabinoid receptor type 1 (CB1R) expression in the brain, which results in positive neurological effects including antidepressant effect, ameliorated memory, neuroplasticity development, and reduced neuroinflammation. However, none of the prior reviews presented a comprehensive correlation between physical activity, the endocannabinoid system, and neuropathologies.

Thus, our review provides a current state of knowledge of the endocannabinoid system, its action in physical activity, as well as neuropathologies and a possible correlation between all those fields. We believe that this might contribute to finding a new preventive and therapeutic approach to both neurological and neurodegenerative disorders.”

https://pubmed.ncbi.nlm.nih.gov/32545780/

https://www.mdpi.com/1422-0067/21/12/4221

Effects of Chronic Cannabidiol Treatment in the Rat Chronic Unpredictable Mild Stress Model of Depression

biomolecules-logo“Several neuropharmacological actions of cannabidiol (CBD) due to the modulation of the endocannabinoid system as well as direct serotonergic and gamma-aminobutyric acidergic actions have recently been identified.

The current study aimed to reveal the effect of a long-term CBD treatment in the chronic unpredictable mild stress (CUMS) model of depression.

Adult male Wistar rats (n = 24) were exposed to various stressors on a daily basis in order to induce anhedonia and anxiety-like behaviors. CBD (10 mg/kg body weight) was administered by daily intraperitoneal injections for 28 days (n = 12). The effects of the treatment were assessed on body weight, sucrose preference, and exploratory and anxiety-related behavior in the open field (OF) and elevated plus maze (EPM) tests. Hair corticosterone was also assayed by liquid chromatography-mass spectrometry.

At the end of the experiment, CBD-treated rats showed a higher rate of body weight gain (5.94% vs. 0.67%) and sucrose preference compared to controls. A significant increase in vertical exploration and a trend of increase in distance traveled in the OF test were observed in the CBD-treated group compared to the vehicle-treated group. The EPM test did not reveal any differences between the groups. Hair corticosterone levels increased in the CBD-treated group, while they decreased in controls compared to baseline (+36.01% vs. -45.91%). In conclusion, CBD exerted a prohedonic effect in rats subjected to CUMS, demonstrated by the increased sucrose preference after three weeks of treatment.

The reversal of the effect of CUMS on hair corticosterone concentrations might also point toward an anxiolytic or antidepressant-like effect of CBD, but this needs further confirmation.”

https://pubmed.ncbi.nlm.nih.gov/32455953/

https://www.mdpi.com/2218-273X/10/5/801

Two-weeks treatment with cannabidiol improves biophysical and behavioral deficits associated with experimental type-1 diabetes.

Neuroscience Letters“The prevalence rates of depression and anxiety are at least two times higher in diabetic patients, increasing morbidity and mortality.

Cannabidiol (CBD) has been identified as a therapeutic agent viable to treat diverse psychiatric disorders. Thus, this study aimed to investigate the effect of CBD treatment (once a day for 14 days starting two weeks after diabetes induction; at doses of 0, 3, 10 or 30 mg/kg, i.p.) on depression- and anxiety-like behaviors associated with experimental diabetes induced by streptozotocin (60 mg/kg; i.p.) in rats.

Levels of plasma insulin, blood glucose, and weight gain were evaluated in all experimental groups, including a positive control group treated with imipramine. The rats were tested in the modified forced swimming test (mFST) and elevated plus maze (EPM) test. Besides, the levels of serotonin (5-HT), noradrenaline (NA) and dopamine (DA) in two emotion-related brain regions, the prefrontal cortex (PFC) and hippocampus (HIP) were evaluated using high-pressure liquid chromatography.

Our results showed that CBD treatment (only at the higher dose of 30 mg/kg) reduced the exaggerated depressive- and anxiogenic-like behaviors of diabetic (DBT) rats, which may be associated with altered 5-HT, NA and/or DA levels observed in the PFC and HIP. Treatment with CBD (higher dose) also induced a significant increase in weight gain and the insulin levels (and consequently reduced glycemia) in DBT rats. The long-term CBD effects gave rise to novel therapeutic strategies to limit the physiological and neurobehavioral deficits in DBT rats.

This approach provided evidence that CBD can be useful for treating psychiatry comorbidities in diabetic patients.”

https://www.ncbi.nlm.nih.gov/pubmed/32360935

“Treatment of diabetic rats with cannabidiol induced antidepressant- and anxiolytic-like behaviors.”

https://www.sciencedirect.com/science/article/abs/pii/S0304394020302901?via%3Dihub

CBD modulates DNA methylation in mice prefrontal cortex and hippocampus of mice exposed to forced swim.

Behavioural Brain Research“Cannabidiol (CBD), a non-psychotomimetic component of Cannabis sativa plant, shows therapeutic potential in psychiatric disorders, including depression.

The molecular mechanisms underlying the antidepressant-like effects of CBD are not yet understood. Previous studies in differentiated skin cells demonstrated that CBD regulates DNA methylation, an overall repressive epigenetic mechanism. Both stress exposure and antidepressant treatment can modulate DNA methylation in the brain, and lead to gene expression changes associated with depression neurobiology.

We investigated herein if the antidepressant effect of CBD could be associated with changes in DNA methylation in the prefrontal cortex (PFC) and hippocampus (HPC) of mice submitted to the forced swimming test (FST).

Altogether, our results indicate that CBD regulates DNA methylation in brain regions relevant for depression neurobiology, suggesting that this mechanism could be related to CBD-induced antidepressant effects.”

https://www.ncbi.nlm.nih.gov/pubmed/32348868

“Cannabidiol (CBD) shows antidepressant-like properties in mice.”

https://www.sciencedirect.com/science/article/pii/S0166432820303260?via%3Dihub

Decreased sensitivity in adolescent versus adult rats to the antidepressant-like effects of cannabidiol.

SpringerLink“Cannabidiol is a non-psychoactive phytocannabinoid with great therapeutic potential in diverse psychiatric disorders; however, its antidepressant potential has been mainly ascertained in adult rats.

OBJECTIVES:

To compare the antidepressant-like response induced by cannabidiol in adolescent and adult rats and the possible parallel modulation of hippocampal neurogenesis.

RESULTS:

Cannabidiol induced differential effects depending on the age and dose administered, with a decreased sensitivity observed in adolescent rats: (1) cannabidiol (30 mg/kg) decreased body weight only in adult rats; (2) cannabidiol ameliorated behavioral despair in adolescent and adult rats, but with a different dose sensitivity (10 vs. 30 mg/kg), and with a different extent (2 vs. 21 days post-treatment); (3) cannabidiol did not modulate anxiety-like behavior at any dose tested in adolescent or adult rats; and (4) cannabidiol increased sucrose intake in adult rats.

CONCLUSIONS:

Our findings support the notion that cannabidiol exerts antidepressant- and anorexigenic-like effects in adult rats and demonstrate a decreased potential when administered in adolescent rats. Moreover, since cannabidiol did not modulate hippocampal neurogenesis (cell proliferation and early neuronal survival) in adolescent or adult rats, the results revealed potential antidepressant-like effects induced by cannabidiol without the need of regulating hippocampal neurogenesis.”

https://www.ncbi.nlm.nih.gov/pubmed/32086540

https://link.springer.com/article/10.1007%2Fs00213-020-05481-4

Possible therapeutic applications of cannabis in the neuropsychopharmacology field.

European Neuropsychopharmacology“Cannabis use induces a plethora of actions on the CNS via its active chemical ingredients, the so-called phytocannabinoids.

These compounds have been frequently associated with the intoxicating properties of cannabis preparations. However, not all phytocannabinoids are psychotropic, and, irrespective of whether they are psychotropic or not, they have also shown numerous therapeutic properties.

These properties are mostly associated with their ability to modulate the activity of an intercellular communication system, the so-called endocannabinoid system, which is highly active in the CNS and has been found altered in many neurological disorders.

Specifically, this includes the neuropsychopharmacology field, with diseases such as schizophrenia and related psychoses, anxiety-related disorders, mood disorders, addiction, sleep disorders, post-traumatic stress disorder, anorexia nervosa and other feeding-related disorders, dementia, epileptic syndromes, as well as autism, fragile X syndrome and other neurodevelopment-related disorders.

Here, we gather, from a pharmacological and biochemical standpoint, the recent advances in the study of the therapeutic relevance of the endocannabinoid system in the CNS, with especial emphasis on the neuropsychopharmacology field. We also illustrate the efforts that are currently being made to investigate at the clinical level the potential therapeutic benefits derived from elevating or inhibiting endocannabinoid signaling in animal models of neuropsychiatric disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/32057592

https://www.sciencedirect.com/science/article/abs/pii/S0924977X20300365?via%3Dihub

Antidepressant-like effects of β-caryophyllene on restraint plus stress-induced depression.

Behavioural Brain Research“Chronic stress is depressogenic by altering neurotrophic and neuroinflammatory environments of the organism. The endocannabinoid system controls cognitive and emotional responses related with stress through the interaction with endocannabinoid receptors. β-Caryophyllene (BCP) is a CB2 agonist that exhibited anti-inflammatory, analgesic effects but minimal psychoactive effects. To test if BCP exhibits antidepressant-like action, animals were chronically restrained with additional stressors for 28 days, and BCP (25, 50, 100 mg/kg) was intraperitoneally injected once a day during the stress inflicting period. Then despair related behaviors and hippocampal expression of neurotrophic, inflammatory and cannabinoid receptor levels were measured. To test the effect of BCP on long-term depression, field potentials were measured during the application of lipopolysaccharide and low frequency stimulation. In the tail suspension test and forced swim test, chronic stress-induced despair behaviors were reduced by BCP. Also BCP improved the stress-related changes in the hippocampal expression of COX-2, BDNF, and CB2 receptor expression. In organotypic hippocampal slices, BCP reduced the lipopolysaccharide-induced intensification of the long-term depression. In conclusion, BCP improved chronic stress related behavioral and biochemical changes. These results suggest that BCP may be effective in treating depression and stress related mental illnesses.”

https://www.ncbi.nlm.nih.gov/pubmed/31862467

https://linkinghub.elsevier.com/retrieve/pii/S0166432819313348

“β-caryophyllene (BCP) is a common constitute of the essential oils of numerous spice, food plants and major component in Cannabis.”   http://www.ncbi.nlm.nih.gov/pubmed/23138934

“Beta-caryophyllene is a dietary cannabinoid.”    https://www.ncbi.nlm.nih.gov/pubmed/18574142

Influence of the CB1 and CB2 cannabinoid receptor ligands on the activity of atypical antidepressant drugs in the behavioural tests in mice.

Pharmacology Biochemistry and Behavior“Available data support the notion that cannabinoids, whose therapeutic value is limited due to severe adverse reactions, could be beneficial as adjunctive agents in the management of mood disorders.

Polytherapy, which is superior to monotherapy in the terms of effectiveness, usually requires lower doses of the individual components. Therefore, the main objective of our study was to determine whether administration of cannabinoid (CB) receptor ligands would enhance the antidepressant activity of atypical antidepressant drugs, i.e. agomelatine and tianeptine.

In summary, the outcomes of the present study showed that activation and inhibition of CB1 receptors as well as inhibition of CB2 receptors may increase the antidepressant activity of tianeptine, whereas only inhibition of CB1 and CB2 receptors has a potential to augment the antidepressant activity of agomelatine.”

https://www.ncbi.nlm.nih.gov/pubmed/31785246

https://www.sciencedirect.com/science/article/pii/S0091305719304873?via%3Dihub

Cannabinoids and the endocannabinoid system in anxiety, depression, and dysregulation of emotion in humans.

Image result for ovid journal“This review is to summarize most recent evidence published in the last 18 months on medical and recreational use of cannabis and cannabinoids in relation to anxiety, depression (unipolar and bipolar), and dysregulation of emotions as part of posttraumatic stress disorders (PTSD) and emotionally instable personality disorders.

It also covers the investigation of endocannabinoids as potential biomarkers in these conditions. This is important with increasing medicinal use of cannabinoids and growing social tolerance towards recreational cannabis use.

RECENT FINDINGS:

There is some recent evidence suggesting cannabinoids, cannabidiol or cannabidiol-enriched cannabis preparations have anxiolytic properties. In addition, depression may be worsened by cannabis use, however, randomized controlled trials (RCT) are lacking.

New evidence also suggests that cannabidiol or cannabidiol-enriched cannabis use for PTSD and emotion regulation can induce hyporesponse to fear and stress. Further, several lines of evidence point to the endocannabinoid system as a key player in some of the reviewed disorders, in particular anxiety and PTSD.

SUMMARY:

The most recent evidence for a therapeutic use of cannabinoids in the reviewed conditions is weak and lacking well designed RCTs. However, there is some indication of the role of the endocannabinoid system in these conditions that warrant further studies.”

https://www.ncbi.nlm.nih.gov/pubmed/31714262

https://insights.ovid.com/crossref?an=00001504-900000000-99165

Antidepressant active ingredients from herbs and nutraceuticals used in TCM: pharmacological mechanisms and prospects for drug discovery.

Pharmacological Research“Depression is a widespread psychological disorder that affects up to 20% of the world’s population. Traditional Chinese medicine (TCM), with its unique curative effect in depression treatment, is gaining increasing attention as the discovery of novel antidepressant drug has become the pursuit of pharmaceutical. This article summarizes the work done on the natural products from TCM that have been reported to conceive antidepressant effects in the past two decades, which can be classified according to various mechanisms including increasing synaptic concentrations of monoamines, alleviating the hypothalamic-pituitary-adrenal (HPA) axis dysfunctions, lightening the impairment of neuroplasticity, fighting towards immune and inflammatory dysregulation. The antidepressant active ingredients identified can be generally divided into saponins, flavonoids, alkaloids, polysaccharides and others. Albiflorin, Baicalein, Berberine chloride, beta-Asarone, cannabidiol, Curcumin, Daidzein, Echinocystic acid (EA), Emodin, Ferulic acid, Gastrodin, Genistein, Ginsenoside Rb1, Ginsenoside Rg1, Ginsenoside Rg3, Hederagenin, Hesperidin, Honokiol, Hyperoside, Icariin, Isoliquiritin, Kaempferol, Liquiritin, L-theanine, Magnolol, Paeoniflorin, Piperine, Proanthocyanidin, Puerarin, Quercetin, Resveratrol (trans), Rosmarinic acid, Saikosaponin A, Senegenin, Tetrahydroxystilbene glucoside and Vanillic acid are Specified in this review. Simultaneously, chemical structures of the active ingredients with antidepressant activities are listed and their sources, models, efficacy and mechanisms are described. Chinese compound prescription and extracts that exert antidepressant effects are also introduced, which may serve as a source of inspiration for further development. In the view of present study, the antidepressant effect of certain TCMs are affirmative and encouraging. However, there are a lot of work needs to be done to evaluate the exact therapeutic effects and mechanisms of those active ingredients, specifically, to establish a unified standard for diagnosis and evaluation of curative effect.”

https://www.ncbi.nlm.nih.gov/pubmed/31706012

https://www.sciencedirect.com/science/article/abs/pii/S1043661819322601?via%3Dihub