Spinal cannabinoid CB1 or CB2 receptors activation attenuates mechanical allodynia in streptozotocin-induced diabetic rats

 Behavioural Pharmacology“Diabetes is a chronic disease associated with a high number of complications such as peripheral neuropathy, which causes sensorial disturbances and may lead to the development of diabetic neuropathic pain (DNP). The current treatment for DNP is just palliative and the drugs may cause severe adverse effects, leading to discontinuation of treatment. Thus, new therapeutic targets need to be urgently investigated.

Studies have shown that cannabinoids have promising effects in the treatment of several pathological conditions, including chronic pain.

Thus, we aimed to investigate the acute effect of the intrathecal injection of CB1 or CB2 cannabinoid receptor agonists N-(2-chloroethyl)-5Z, 8Z, 11Z, 14Z-eicosatetraenamide (ACEA) or JWH 133, respectively (10, 30 or 100 μg/rat) on the mechanical allodynia associated with experimental diabetes induced by streptozotocin (60 mg/kg; intraperitoneal) in rats.

Cannabinoid receptor antagonists CB1 AM251 or CB2 AM630 (1 mg/kg) were given before treatment with respective agonists to confirm the involvement of cannabinoid CB1 or CB2 receptors. Rats with diabetes exhibited a significant reduction on the paw mechanical threshold 2 weeks after diabetes induction, having the maximum effect observed 4 weeks after the streptozotocin injection. This mechanical allodynia was significantly improved by intrathecal treatment with ACEA or JWH 133 (only at the higher dose of 100 μg). Pre-treatment with AM251 or AM630 significantly reverted the anti-allodynic effect of the ACEA or JWH 133, respectively.

Considering the clinical challenge that the treatment of DPN represents, this study showed for the first time, that the intrathecal cannabinoid receptors agonists may represent an alternative for the treatment of DNP.”

https://pubmed.ncbi.nlm.nih.gov/32804775/

Substance use disorders and risk of severe maternal morbidity in the United States

Drug and Alcohol Dependence “The contribution of substance use disorders to the burden of severe maternal morbidity in the United States is poorly understood. The objective was to estimate the independent association between substance use disorders during pregnancy and risk of severe maternal morbidity.

Results: Pregnant women with an opioid use disorder had an increased risk of severe maternal morbidity compared with women without an opioid use disorder (18-34 years: aOR: 1.51; 95 % CI: 1.41,1.61, >34 years: aOR: 1.17; 95 % CI: 1.00,1.38). Compared with their counterparts without stimulant use disorders, pregnant women with a simulant use disorder (amphetamines, cocaine) had an increased risk of severe maternal morbidity (18-34 years: aOR: 1.92; 95 % CI: 1.80,2.0, >34 years: aOR: 1.85; 95 % CI: 1.66,2.06). Cannabis use disorders were not associated with an increased risk of severe maternal morbidity.

Conclusion: Substance use disorders during pregnancy, particularly opioids, amphetamines, and cocaine use disorders, may contribute to severe maternal morbidity in the United States.”

https://pubmed.ncbi.nlm.nih.gov/32846369/

“Cannabis use disorder was not associated with increased risk of severe maternal morbidity.”

https://www.sciencedirect.com/science/article/abs/pii/S0376871620304014?via%3Dihub

Cannabis Improves Obsessive-Compulsive Disorder-Case Report and Review of the Literature

Archive of "Frontiers in Psychiatry". “Although several lines of evidence support the hypothesis of a dysregulation of serotoninergic neurotransmission in the pathophysiology of obsessive-compulsive disorder (OCD), there is also evidence for an involvement of other pathways such as the GABAergic, glutamatergic, and dopaminergic systems.

Only recently, data obtained from a small number of animal studies alternatively suggested an involvement of the endocannabinoid system in the pathophysiology of OCD reporting beneficial effects in OCD-like behavior after use of substances that stimulate the endocannabinoid system.

In humans, until today, only two case reports are available reporting successful treatment with dronabinol (tetrahydrocannabinol, THC), an agonist at central cannabinoid CB1 receptors, in patients with otherwise treatment refractory OCD. In addition, data obtained from a small open uncontrolled trial using the THC analogue nabilone suggest that the combination of nabilone plus exposure-based psychotherapy is more effective than each treatment alone.

These reports are in line with data from a limited number of case studies and small controlled trials in patients with Tourette syndrome (TS), a chronic motor and vocal tic disorder often associated with comorbid obsessive compulsive behavior (OCB), reporting not only an improvement of tics, but also of comorbid OCB after use of different kinds of cannabis-based medicines including THC, cannabis extracts, and flowers.

Here we present the case of a 22-year-old male patient, who suffered from severe OCD since childhood and significantly improved after treatment with medicinal cannabis with markedly reduced OCD and depression resulting in a considerable improvement of quality of life. In addition, we give a review of current literature on the effects of cannabinoids in animal models and patients with OCD and suggest a cannabinoid hypothesis of OCD.”

https://pubmed.ncbi.nlm.nih.gov/32848902/

https://www.frontiersin.org/articles/10.3389/fpsyt.2020.00681/full

Effects of ∆ 9-tetrahydrocannabinol on aversive memories and anxiety: a review from human studies

Medscape | BMC Psychiatry - Content Listing“Posttraumatic stress disorder (PTSD) may stem from the formation of aberrant and enduring aversive memories. Some PTSD patients have recreationally used Cannabis, probably aiming at relieving their symptomatology.

Here, we seek to review and discuss the effects of THC on aversive memory extinction and anxiety in healthy humans and PTSD patients.

Results: At low doses, THC can enhance the extinction rate and reduce anxiety responses. Both effects involve the activation of cannabinoid type-1 receptors in discrete components of the corticolimbic circuitry, which could couterbalance the low “endocannabinoid tonus” reported in PTSD patients. The advantage of associating CBD with THC to attenuate anxiety while minimizing the potential psychotic or anxiogenic effect produced by high doses of THC has been reported. The effects of THC either alone or combined with CBD on aversive memory reconsolidation, however, are still unknown.

Conclusions: Current evidence from healthy humans and PTSD patients supports the THC value to suppress anxiety and aversive memory expression without producing significant adverse effects if used in low doses or when associated with CBD. Future studies are guaranteed to address open questions related to their dose ratios, administration routes, pharmacokinetic interactions, sex-dependent differences, and prolonged efficacy.”

https://pubmed.ncbi.nlm.nih.gov/32842985/

“Altogether, the findings encourage future controlled studies evaluating the effects of low doses of THC to attenuate aversive/traumatic memory expression in PTSD patients.”

https://bmcpsychiatry.biomedcentral.com/articles/10.1186/s12888-020-02813-8

The Treatment of Cognitive, Behavioural and Motor Impairments from Brain Injury and Neurodegenerative Diseases through Cannabinoid System Modulation-Evidence from In Vivo Studies

jcm-logo“Neurological disorders such as neurodegenerative diseases or traumatic brain injury are associated with cognitive, motor and behavioural changes that influence the quality of life of the patients. Although different therapeutic strategies have been developed and tried until now to decrease the neurological decline, no treatment has been found to cure these pathologies.

In the last decades, the implication of the endocannabinoid system in the neurological function has been extensively studied, and the cannabinoids have been tried as a new promising potential treatment. In this study, we aimed to overview the recent available literature regarding in vivo potential of natural and synthetic cannabinoids with underlying mechanisms of action for protecting against cognitive decline and motor impairments.

The results of studies on animal models showed that cannabinoids in traumatic brain injury increase neurobehavioral function, working memory performance, and decrease the neurological deficit and ameliorate motor deficit through down-regulation of pro-inflammatory markers, oedema formation and blood-brain barrier permeability, preventing neuronal cell loss and up-regulating the levels of adherence junction proteins.

In neurodegenerative diseases, the cannabinoids showed beneficial effects in decreasing the motor disability and disease progression by a complex mechanism targeting more signalling pathways further than classical receptors of the endocannabinoid system. In light of these results, the use of cannabinoids could be beneficial in traumatic brain injuries and multiple sclerosis treatment, especially in those patients who display resistance to conventional treatment.”

https://pubmed.ncbi.nlm.nih.gov/32726998/

https://www.mdpi.com/2077-0383/9/8/2395

Alleviative effects of Cannabis flower on migraine and headache

 Journal of Integrative Medicine“Few studies to date have measured the real-time effects of consumption of common and commercially available Cannabis products for the treatment of headache and migraine under naturalistic conditions. This study examines, for the first time, the effectiveness of using dried Cannabis flower, the most widely used type of Cannabis product in the United States, in actual time for treatment of headache- and migraine-related pain and the associations between different product characteristics and changes in symptom intensity following Cannabis use.

Results

Ninety-four percent of users experienced symptom relief within a two-hour observation window. The average symptom intensity reduction was 3.3 points on a 0−10 scale (standard deviation = 2.28, Cohen’s d = 1.58), with males experiencing greater relief than females (P < 0.001) and a trend that younger users (< 35 years) experience greater relief than older users (P = 0.08). Mixed effects regression models showed that, among the known (i.e., labeled) product characteristics, tetrahydrocannabinol levels 10% and higher are the strongest independent predictors of symptom relief, and this effect is particularly prominent in headache rather than migraine sufferers (P < 0.05), females (P < 0.05) and younger users (P < 0.001). Females and younger users also appear to gain greater symptom relief from flower labeled as “C. indica” rather than “C. sativa” or other hybrid strains.

Conclusion

These results suggest that whole dried Cannabis flower may be an effective medication for treatment of migraine- and headache-related pain, but the effectiveness differs according to characteristics of the Cannabis plant, the combustion methods, and the age and gender of the patient.”

https://www.sciencedirect.com/science/article/abs/pii/S2095496420300741

Protective role of neuronal and lymphoid cannabinoid CB 2 receptors in neuropathic pain

 eLife logo“Cannabinoid CB2 receptor (CB2) agonists are potential analgesics void of psychotropic effects.

Peripheral immune cells, neurons and glia express CB2, however the involvement of CB2 from these cells in neuropathic pain remains unresolved. We explored spontaneous neuropathic pain through on-demand self-administration of the selective CB2 agonist JWH133 in wild-type and knockout mice lacking CB2 in neurons, monocytes or constitutively. Operant self-administration reflected drug-taking to alleviate spontaneous pain, nociceptive and affective manifestations. While constitutive deletion of CB2 disrupted JWH133-taking behavior, this behavior was not modified in monocyte-specific CB2 knockouts and was increased in mice defective in neuronal CB2 knockouts suggestive of increased spontaneous pain. Interestingly, CB2-positive lymphocytes infiltrated the injured nerve and possible CB2transfer from immune cells to neurons was found. Lymphocyte CB2depletion also exacerbated JWH133 self-administration and inhibited antinociception.

This work identifies a simultaneous activity of neuronal and lymphoid CB2that protects against spontaneous and evoked neuropathic pain.”

https://pubmed.ncbi.nlm.nih.gov/32687056/

https://elifesciences.org/articles/55582

Pharmacological activation of CB2 receptor protects against ethanol-induced myocardial injury related to RIP1/RIP3/MLKL-mediated necroptosis

 Molecular and Cellular Biochemistry | Home“Chronic ethanol abuse can lead to harmful consequences for the heart, resulting in systolic dysfunction, variability in the heart rate, arrhythmia, and cardiac remodelling. However, the precise molecular mechanism responsible for ethanol-induced cardiomyopathy is poorly understood. In this regard, the present study aimed to describe the RIP1/RIP3/MLKL-mediated necroptotic cell death that may be involved in ethanol-induced cardiomyopathy and characterize CBR-mediated effects on the signalling pathway and myocardial injury.

We performed an ethanol vapour administration experiment to analyse the effects of ethanol on cardiac structure and function in male C57BL/6J mice. Ethanol induced a significant decline in the cardiac structure and function, as evidenced by a decline in ejection fraction and fractional shortening, and an increase in serum Creatine Kinase levels, myocardial collagen content, and inflammatory reaction. Furthermore, ethanol also upregulated the expression levels of necroptosis-related markers such as p-RIP1, p-RIP3, and p-MLKL in the myocardium. Nec-1 treatment exerted significant cardioprotective effects by salvaging the heart tissue, improving the cardiac function, and mitigating inflammation and necroptosis.

In addition, ethanol abuse caused an imbalance in the endocannabinoid system and regulated two cannabinoid receptors (CB1R and CB2R) in the myocardium. Treatment with selective CB2R agonists, JWH-133 or AM1241, markedly improved the cardiac dysfunction and reduced the ethanol-induced necroptosis in the myocardium.

Altogether, our data provide evidence that ethanol abuse-induced cardiotoxicity can possibly be attributed to the RIP1/RIP3/MLKL-mediated necroptosis. Moreover, pharmacological activation of CB2R may represent a new cardioprotective strategy against ethanol-induced cardiotoxicity.”

https://pubmed.ncbi.nlm.nih.gov/32681290/

https://link.springer.com/article/10.1007%2Fs11010-020-03828-1

Structural basis of signaling of cannabinoids receptors: paving a way for rational drug design in controling mutiple neurological and immune diseases

Dundee University rank & funding : Compute Scotland“Cannabinoids (CBs), analgesic drugs used for thousands of years, were first found in Cannabis sativa, and the multiple CBs used medicinally, such as tetrahydrocannabinol (THC), cannabidiol (CBD) and dozens more, have complex structures. In addition to their production by plants, CBs are naturally present in the nerves and immune systems of humans and animals.

Both exogenous and endogenous CBs carry out a variety of physiological functions by engaging with two CB receptors, the CB1 and CB2 receptors, in the human endocannabinoid system (ECS). Both CB1 and CB2 are G protein-coupled receptors that share a 7-transmembrane (7TM) topology. CB1, known as the central CB receptor, is mainly distributed in the brain, spinal cord, and peripheral nervous system. CB1 activation in the human body typically promotes the release of neurotransmitters, controls pain and memory learning, and regulates metabolism and the cardiovascular system.

Clinically, CB1 is a direct drug target for drug addiction, neurodegenerative diseases, pain, epilepsy, and obesity. Unlike the exclusive expression of CB1 in the nervous system, CB2 is mainly distributed in peripheral immune cells. Selective CB2 agonists would have therapeutic potential in the treatment of inflammation and pain and avoid side effects caused by currently used clinical drugs.

Although significant progress has been made in developing agonists toward CB receptors, efficient clinical drugs targeting CB receptors remain lacking due to their complex signaling mechanisms. The recent structural elucidation of CB receptors has greatly aided our understanding of the activation and signal transduction mechanisms of CB receptors.

Recent structural characterizations of CB receptors will greatly facilitate the design of new ligands to modulate the selective functions of CB receptors. Notably, the CBD was approved by the Food and Drug Administration (FDA) in 2018 to treat epilepsy. We now look forward to more drugs targeting these two CB receptors for clinical usage in the near future.”

https://pubmed.ncbi.nlm.nih.gov/32694501/

https://www.nature.com/articles/s41392-020-00240-5

figure1

The endocannabinoid system

Essays in Biochemistry “Thirty years ago, the discovery of a cannabinoid (CB) receptor that interacts with the psychoactive compound in Cannabis led to the identification of anandamide, an endogenous receptor ligand or endocannabinoid. Research on endocannabinoids has since exploded, and additional receptors along with their lipid mediators and signaling pathways continue to be revealed. Specifically, in humans, the release of endocannabinoids from membrane lipids occurs on demand and the signaling process is rapidly attenuated by the breakdown of the ligand suggesting a tight regulation of the endocannabinoid system (ECS). Additionally, the varying distribution of CB receptors between the central nervous system and other tissues allows for the ECS to participate in a wide range of cognitive and physiological processes. Select plant-derived ‘phyto’cannabinoids such as Δ-9-tetrahydrocannabinol (Δ9-THC) bind to the CB receptors and trigger the ECS, and in the case of Δ9-THC, while it has therapeutic value, can also produce detrimental effects. Current research is aimed at the identification of additional phytocannabinoids with minimal psychotropic effects with potential for therapeutic development. Although decades of research on the ECS and its components have expanded our understanding of the mechanisms and implications of endocannabinoid signaling in mammals, it continues to evolve. Here, we provide a brief overview of the ECS and its overlap with other related lipid-mediated signaling pathways.”

https://pubmed.ncbi.nlm.nih.gov/32648908/

“Therapeutic intervention in the dysregulation of the ECS will no doubt involve new phytocannabinoids and various synthetic CBs with which to control an increasing list of ECS- related pathologies.”

https://portlandpress.com/essaysbiochem/article/doi/10.1042/EBC20190086/225762/The-endocannabinoid-system

Anandamide and 2-AG are the principal endogenous ligands that define the classical endocannabinoid signaling system (ECS).