Cannabinoid Signaling in the Skin: Therapeutic Potential of the “C(ut)annabinoid” System.

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“The endocannabinoid system (ECS) has lately been proven to be an important, multifaceted homeostatic regulator, which influences a wide-variety of physiological processes all over the body. Its members, the endocannabinoids (eCBs; e.g., anandamide), the eCB-responsive receptors (e.g., CB₁, CB₂), as well as the complex enzyme and transporter apparatus involved in the metabolism of the ligands were shown to be expressed in several tissues, including the skin. Although the best studied functions over the ECS are related to the central nervous system and to immune processes, experimental efforts over the last two decades have unambiguously confirmed that cutaneous cannabinoid (“c[ut]annabinoid”) signaling is deeply involved in the maintenance of skin homeostasis, barrier formation and regeneration, and its dysregulation was implicated to contribute to several highly prevalent diseases and disorders, e.g., atopic dermatitis, psoriasis, scleroderma, acne, hair growth and pigmentation disorders, keratin diseases, various tumors, and itch. The current review aims to give an overview of the available skin-relevant endo- and phytocannabinoid literature with a special emphasis on the putative translational potential, and to highlight promising future research directions as well as existing challenges.”

https://www.ncbi.nlm.nih.gov/pubmed/30845666

https://www.mdpi.com/1420-3049/24/5/918

Novel protective effect of O-1602 and abnormal cannabidiol, GPR55 agonists, on ER stress-induced apoptosis in pancreatic β-cells.

Biomedicine & Pharmacotherapy

“Insulin resistance and β-cell dysfunction are the main defects in Type 2 Diabetes Mellitus (T2DM), and β-cell dysfunction and apoptosis is the critical determinant in the progression of T2DM. G-protein coupled receptor 55 (GPR55) is an orphan G-protein coupled receptor, which is activated by endocannabinoids and lipid transmitters. Recently, GPR55 was shown to regulate glucose and energy homeostasis, however its role in β-cell apoptosis was not studied. Therefore, in this study, we investigated the novel effect of GPR55 agonists, O-1602 and abnormal cannabidiol (Abn-CBD), on endoplasmic reticulum (ER) stress-induced apoptosis in mouse pancreatic β-cell lines, MIN6 and Beta-TC-6, and its underlying mechanisms. Our results showed that O-1602 and Abn-CBD reduced ER stress-induced apoptosis in MIN6 and Beta-TC-6 cells. This was through the phosphorylation of 3′-5′-cyclic adenosine monophosphate response element-binding protein (CREB) in β-cells, hence activating CREB downstream anti-apoptotic genes, Bcl-2 and Bcl-xL. Moreover, O-1602 and Abn-CBD directly activated kinases, CaMKIV, Erk1/2 and PKA, to induce CREB phosphorylation. Therefore, our results indicated that GPR55 agonists protected from β-cell apoptosis through CREB activation, thus up-regulating anti-apoptotic genes. In conclusion, our study provided a novel protective effect of GPR55 agonists on ER stress-induced apoptosis in β-cells and its underlying mechanisms mediating this protection, therefore we suggested that GPR55 might be a therapeutic target for T2DM.”

https://www.ncbi.nlm.nih.gov/pubmed/30841431

https://www.sciencedirect.com/science/article/pii/S0753332218375668?via%3Dihub

New Insights of Uterine Leiomyoma Pathogenesis: Endocannabinoid System.

 

“The aim of this study was to determine if components of the endocannabinoid system are modulated in uterine leiomyomas (fibroids). Components studied included cannabinoid receptors 1 (CB1) and 2 (CB2); the G protein-coupled receptor GPR55; transient potential vanilloid receptor 1 (TRPV1) and the endocannabinoid modulating enzymes N-acylphosphatidylethanolamine-specific phospholipase D (NAPE-PLD) and fatty acid amide hydrolase (FAAH), and their N-acylethanolamine (NAE) ligands: N-arachidonylethanolamine (AEA), N-oleoylethanolamine (OEA), and N-palmityolethanaolamine (PEA). MATERIAL AND METHODS Transcript levels of CB1, CB2, TRPV1, GPR55, NAPE-PLD, and FAAH were measured using RT-PCR and correlated with the tissue levels of the 3 NAEs in myometrial tissues. The tissues studied were: 1) fibroids, 2) myometrium adjacent/juxtaposed to the fibroid lesions, and 3) normal myometrium. Thirty-seven samples were processed for NAE measurements and 28 samples were used for RT-PCR analyses. RESULTS FAAH expression was significantly lower in fibroids, resulting in a NAPE-PLD: FAAH ratio that favors higher AEA levels in pre-menopausal tissues, whilst PEA levels were significantly lower, particularly in post-menopausal women, suggesting PEA protects against fibroid pathogenesis. The CB1: CB2 ratio was lower in fibroids, suggesting that loss of CB1 expression affects the fibroid cell phenotype. Significant correlations between reduced FAAH, CB1, and GPR55 expression and PEA in fibroids indicate that the loss of these endocannabinoid system components are biomarkers of leiomyomata. CONCLUSIONS Loss of expression of CB1, FAAH, GPR55, and PEA production are linked to the pathogenesis of uterine fibroids and further understanding of this might eventually lead to better disease indicators or the development of therapeutic potentials that might eventually be used in the management of uterine fibroids.”

https://www.ncbi.nlm.nih.gov/pubmed/30842391

https://basic.medscimonit.com/abstract/index/idArt/914019

The Endocannabinoid System and Cannabidiol’s Promise for the Treatment of Substance Use Disorder.

 Related image“Substance use disorder is characterized by repeated use of a substance, leading to clinically significant distress, making it a serious public health concern. The endocannabinoid system plays an important role in common neurobiological processes underlying substance use disorder, in particular by mediating the rewarding and motivational effects of substances and substance-related cues. In turn, a number of cannabinoid drugs (e.g., rimonabant, nabiximols) have been suggested for potential pharmacological treatment for substance dependence. Recently, cannabidiol (CBD), a non-psychoactive phytocannabinoid found in the cannabis plant, has also been proposed as a potentially effective treatment for the management of substance use disorder. Animal and human studies suggest that these cannabinoids have the potential to reduce craving and relapse in abstinent substance users, by impairing reconsolidation of drug-reward memory, salience of drug cues, and inhibiting the reward-facilitating effect of drugs. Such functions likely arise through the targeting of the endocannabinoid and serotonergic systems, although the exact mechanism is yet to be elucidated. This article seeks to review the role of the endocannabinoid system in substance use disorder and the proposed pharmacological action supporting cannabinoid drugs’ therapeutic potential in addictions, with a focus on CBD. Subsequently, this article will evaluate the underlying evidence for CBD as a potential treatment for substance use disorder, across a range of substances including nicotine, alcohol, psychostimulants, opioids, and cannabis. While early research supports CBD’s promise, further investigation and validation of CBD’s efficacy, across preclinical and clinical trials will be necessary.”

https://www.ncbi.nlm.nih.gov/pubmed/30837904

https://www.frontiersin.org/articles/10.3389/fpsyt.2019.00063/full

β-Caryophyllene, a natural bicyclic sesquiterpene attenuates doxorubicin-induced cardiotoxicity via activation of myocardial cannabinoid type-2 (CB2) receptors in rats.

Chemico-Biological Interactions

“The cannabinoid type 2 receptor (CB2) has recently emerged as an important therapeutic target for cancer as well as cardiovascular diseases. The CB2 receptor downregulation has been reported in solid tumors and cardiovascular diseases, therefore the CB2receptor activation has been considered as a viable strategy for chemotherapy as well as cardioprotection.

In chemotherapy, doxorubicin (DOX) is an important drug that continues to be the mainstay of chemotherapy in solid tumors, leukemia, and lymphoma. However, the use of DOX is often limited due to its lethal cardiotoxicity. Considering the role of CB2 receptors in cardiovascular diseases and cancer, the activation of CB2 receptors may protect against DOX-induced chronic cardiotoxicity in rats.

In the present study, we investigated the cardioprotective effect of a selective CB2 receptor agonist; β-Caryophyllene (BCP), a natural bicyclic sesquiterpene, against DOX-induced chronic cardiotoxicity in rats. AM630, a CB2 receptor antagonist was administered as a pharmacological challenge prior to BCP treatment to demonstrate CB2 receptor mediated cardioprotective mechanism of BCP. DOX (2.5 mg/kg) was injected intraperitoneally once a week for five weeks to induce chronic cardiotoxicity in rats.

BCP was also injected into rats six days a week for a total duration of five weeks. DOX induced a significant decline in cardiac function and oxidative stress evidenced by the depletion of antioxidant enzymes, glutathione, and increased lipid peroxidation. DOX also triggered activation of nuclear factor kappa B (NF-κB) and increased the levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) and expression of the inflammatory mediators (iNOS and COX-2) in the heart.

Furthermore, DOX also upregulated the expression of pro-apoptotic markers such as Bax, p53, cleaved PARP, active caspase-3 and downregulated anti-apoptotic marker Bcl-2 in the myocardium. BCP treatment exerted significant cardioprotective effect by salvaging the heart tissues, improving cardiac function, mitigating oxidative stress, inflammation, and apoptosis. The histological and ultrastructural studies also appear in line with our findings of biochemical and molecular parameters.

The CB2 receptor-mediated cardioprotective mechanism was further confirmed by the abrogation of the beneficial effects of BCP with prior administration of the CB2 receptor antagonist; AM630.

Our study revealed the novel mechanism of BCP in cardioprotection against DOX-induced chronic cardiotoxicity by the activation of CB2 receptors.”

https://www.ncbi.nlm.nih.gov/pubmed/30836069

https://www.sciencedirect.com/science/article/pii/S0009279718316284?via%3Dihub

“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

Expression of Cannabinoid Receptors in Myometrium and its Correlation With Dysmenorrhea in Adenomyosis.

 

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“The myometrium, especially the junctional zone (JZ), is now well documented to have a role in the pathogenesis of adenomyosis. Cannabinoid receptors have been shown to participate in the establishment of endometriosis and its pain perception. However, its relation to adenomyosis has not been identified yet. The aim of this study was to investigate the expression of cannabinoid receptor type I (CB1) and type II (CB2) in myometrium of uteri with and without adenomyosis and determine the correlation between their levels and clinical parameters of adenomyosis. We collected tissue samples of JZ and the outer myometrium from 45 premenopausal women with adenomyosis and 34 women without adenomyosis. CB1 and CB2 messenger RNA (mRNA) and protein expression levels were evaluated by the use of Western blotting and real-time quantitative polymerase chain reaction from all samples. Clinical information on the severity of dysmenorrhea and other data were collected. We found both CB1 and CB2 mRNA and protein levels in women with adenomyosis were significantly higher than those of controls, and CB1 expression levels in JZ were positively correlated with the severity of dysmenorrhea. These data suggest that cannabinoid receptor CB1 may be involved in the pathogenesis of dysmenorrhea in adenomyosis and may be a potential therapeutic target.”

https://www.ncbi.nlm.nih.gov/pubmed/30832539

https://journals.sagepub.com/doi/abs/10.1177/1933719119833483?journalCode=rsxb

Second Cannabinoid Receptor Has the Yin to the First Receptor’s Yang

“Understanding the diverse effects that cannabis has on the human body is imperative if we hope to take advantage of its medicinal properties to treat various disorders. As such, elucidating the molecular structure of the receptors that bind endocannabinoids is a critical step toward developing selective drugs that can differentiate between the two known receptors—CB1 and CB2—for these molecules. Since the structure of the CB1 receptor was resolved a few years ago, an international team of researchers led by scientists at the iHuman Institute within ShanghaiTech University has just published the crystal structure of the human type 2 cannabinoid receptor, CB2.

Findings from the new study—published recently in Cell through an article titled “Crystal Structure of the Human Cannabinoid Receptor CB2”—should be helpful in the development of drugs against inflammatory, neurodegenerative, and other diseases. The study authors compared the newly discovered structure to that of the CB1 receptor, deeming the two receptors to be the “yin and yang” of the human endocannabinoid system.”

“Crystal Structure of the Human Cannabinoid Receptor CB1” https://www.cell.com/fulltext/S0092-8674(16)31385-X
“Crystal Structure of the Human Cannabinoid Receptor CB2” https://www.cell.com/cell/pdf/S0092-8674(18)31625-8.pdf
“This study compares newly discovered structures to those of the CB1 receptor, and deems the two receptors to be the Yin and Yang of the human endocannabinoid system, which is a signalling system that regulates biological processes such as pain, immune function, metabolism, and neuronal activities among others.” https://www.worldhealth.net/news/ying-yang-second-cannabinoid-receptor/

Role of endocannabinoid system in dopamine signalling within the reward circuits affected by chronic pain.

Pharmacological Research

“The association between chronic pain, depression and anxiety has gained particular attention due to high rates of comorbidity. Recent data demonstrated that the mesolimbic reward circuitry is involved in the pathology of chronic pain. Interestingly, the mesolimbic reward circuit participates both in pain perception and in pain relief.

The endocannabinoid system (ECS) has emerged as a highly relevant player involved in both pain perception and reward processing. Targeting ECS could become a novel treatment strategy for chronic pain patients.

However, little is known about the underlying mechanisms of action of cannabinoids at the intersection of neurochemical changes in reward circuits and chronic pain. Because understanding the benefits and risks of cannabinoids is paramount, the aim of this review is to evaluate the state-of-art knowledge about the involvement of the ECS in dopamine signalling within the reward circuits affected by chronic pain.”

https://www.ncbi.nlm.nih.gov/pubmed/30831242

https://www.sciencedirect.com/science/article/abs/pii/S1043661819300088?via%3Dihub

CB2 Receptor Stimulation and Dexamethasone Restore the Anti-Inflammatory and Immune-Regulatory Properties of Mesenchymal Stromal Cells of Children with Immune Thrombocytopenia.

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“Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by antibody-mediated platelet destruction, with a complex and unclear pathogenesis. The impaired immunosuppressive capacity of mesenchymal stromal cells in ITP patients (ITP-MSCs) might play a role in the development of the disease. Correcting the MSC defects could represent an alternative therapeutic approach for ITP.

High-dose dexamethasone (HD-Dexa) is the mainstay of the ITP therapeutic regimen, although it has several side effects. We previously demonstrated a role for cannabinoid receptor 2 (CB₂) as a mediator of anti-inflammatory and immunoregulatory properties of human MSCs.

We analyzed the effects of CB₂ stimulation, with the selective agonist JWH-133, and of Dexa alone and in combination on ITP-MSC survival and immunosuppressive capacity. We provided new insights into the pathogenesis of ITP, suggesting CB₂ receptor involvement in the impairment of ITP-MSC function and confirming MSCs as responsive cellular targets of Dexa. Moreover, we demonstrated that CB₂ stimulation and Dexa attenuate apoptosis, via Bcl2 signaling, and restore the immune-modulatory properties of MSCs derived from ITP patients.

These data suggest the possibility of using Dexa in combination with JWH-133 in ITP, reducing its dose and side effects but maintaining its therapeutic benefits.”

https://www.ncbi.nlm.nih.gov/pubmed/30823385

https://www.mdpi.com/1422-0067/20/5/1049

Plant-Based Modulators of Endocannabinoid Signaling.

Journal of Natural Products

“Extracts from Cannabis species have aided the discovery of the endocannabinoid signaling system (ECSS) and phytocannabinoids that possess broad therapeutic potential. Whereas the reinforcing effects of C. sativa are largely attributed to CB1 receptor agonism by Δ9-tetrahydrocannabinol (Δ9-THC), the observed medicinal effects of Cannabis arise from the combined actions of various compounds. In addition to compounds bearing a classical cannabinoid structure, naturally occurring fatty acid amides and esters resembling anandamide and 2-arachidonoyl glycerol isolated from non- Cannabis species are also valuable tools for studying ECSS function. This review highlights the potential of plant-based secondary metabolites from Cannabis and unrelated species as ECSS modulators.”

https://www.ncbi.nlm.nih.gov/pubmed/30816712

https://pubs.acs.org/doi/10.1021/acs.jnatprod.8b00874