Category Archives: Endocannabinoid System

Radioligands for Positron Emission Tomography Imaging of Cannabinoid type 2 Receptor.

Posted on by

Journal of Labelled Compounds and Radiopharmaceuticals

“The cannabinoid type 2 (CB2) receptor is an immunomodulatory receptor mainly expressed in peripheral cells and organs of the immune system. The expression level of CB2 in the central nervous system under physiological conditions is negligible, however under neuroinflammatory conditions an upregulation of CB2 protein or mRNA mainly co-localized with activated microglial cells has been reported.

Consequently, CB2 agonists have been confirmed to play a role in neuroprotective and anti-inflammatory processes.

A suitable PET radioligand for imaging CB2 would provide an invaluable research tool to explore the role of CB2 receptor expression in inflammatory disorders. In this review, we provide a summary of so far published CB2 radioligands as well as their in vitro and in vivo binding characteristics.”

https://www.ncbi.nlm.nih.gov/pubmed/29110331

http://onlinelibrary.wiley.com/doi/10.1002/jlcr.3579/abstract

Cannabinoid-1 receptor neutral antagonist reduces binge-like alcohol consumption and alcohol-induced accumbal dopaminergic signaling.

Posted on by

Image result for Neuropharmacology.

“Binge alcohol (ethanol) drinking is associated with profound adverse effects on our health and society. Rimonabant (SR141716A), a CB1 receptor inverse agonist, was previously shown to be effective for nicotine cessation and obesity. However, studies using rimonabant were discontinued as it was associated with an increased risk of depression and anxiety.

In the present study, we examined the pharmacokinetics and effects of AM4113, a novel CB1 receptor neutral antagonist on binge-like ethanol drinking in C57BL/6J mice using a two-bottle choice drinking-in-dark (DID) paradigm.

The results indicated a slower elimination of AM4113 in the brain than in plasma. AM4113 suppressed ethanol consumption and preference without having significant effects on body weight, ambulatory activity, preference for tastants (saccharin and quinine) and ethanol metabolism. AM4113 pretreatment reduced ethanol-induced increase in dopamine release in nucleus accumbens.

Collectively, these data suggest an important role of CB1 receptor-mediated regulation of binge-like ethanol consumption and mesolimbic dopaminergic signaling, and further points to the potential utility of CB1 neutral antagonists for the treatment of binge ethanol drinking.”

https://www.ncbi.nlm.nih.gov/pubmed/29109060

 

Increased expression of type 1 cannabinoid (CB1) receptor among patients with rotator cuff lesions and shoulder stiffness.

Posted on by

:Journal of Shoulder and Elbow Surgery Home

“Shoulder stiffness is a disease manifested by pain, limited range of motion, and functional disability. The inflammatory and fibrosis processes play a substantial role in the pathogenesis of shoulder stiffness. The CB1 receptor has been recognized to mediate the processes of pathologic fibrosis.

This study investigated the role of the CB1 pathway in pathogenesis of rotator cuff lesions with shoulder stiffness.

The CB1 pathway is involved in the pathogenesis of shoulder stiffness. It may be a promising target for the treatment of rotator cuff lesions with shoulder stiffness.”

https://www.ncbi.nlm.nih.gov/pubmed/29108858

http://www.jshoulderelbow.org/article/S1058-2746(17)30589-X/fulltext

Cannabinoid receptor 1/2 double-knockout mice develop epilepsy.

Posted on by

Epilepsia

“The endocannabinoid system has gained attention as an important modulator of activity in the central nervous system. Initial studies focused on cannabinoid receptor 1 (CB1), which is widely expressed in the brain, but recent work also implicates cannabinoidreceptor 2 (CB2) in modulating neuronal activity.

Both receptors are capable of reducing neuronal activity, generating interest in cannabinoid receptor agonists as potential anticonvulsants.

CB1 (Cnr1) and CB2 (Cnr2) single-knockout mice have been generated, with the former showing heightened seizure sensitivity, but not overt seizures. Given overlapping and complementary functions of CB1 and CB2 receptors, we queried whether double-knockout mice would show an exacerbated neurological phenotype.

Strikingly, 30% of double-knockout mice exhibited provoked behavioral seizures, and 80% were found to be epileptic following 24/7 video-electroencephalographic monitoring. Single-knockout animals did not exhibit seizures. These findings highlight the importance of the endocannabinoid system for maintaining network stability.”

https://www.ncbi.nlm.nih.gov/pubmed/29105060

http://onlinelibrary.wiley.com/doi/10.1111/epi.13930/abstract

The Endocannabinoid System Differentially Regulates Escape Behavior in Mice.

Posted on by

Image result for frontiers in behavioral neuroscience

“Among the hardwired behaviors, fear or survival responses certainly belong to the most evolutionary conserved ones. However, higher animals possess the ability to adapt to certain environments (e.g., novel foraging grounds), and, therefore, those responses need to be plastic. Previous studies revealed a cell-type specific role of the endocannabinoid system in novelty fear, conditioned fear and active vs. passive avoidance in a shuttle box paradigm.

In this study we aim to investigate, whether knocking-out the cannabinoidreceptor type-1 (CB1) on cortical glutamatergic (Glu-CB1-/-) or GABAergic (GABA-CB1-/-) neurons differentially affects the level of behavioral inhibition, which could ultimately lead to differences in escape behavior.

Taken together, we could show that CB1 on cortical glutamatergic terminals is important for the acquisition of active avoidance, as the absence of CB1 on these neurons creates a bias toward inhibitory avoidance. This is the case in situations without punishment such as electric footshocks. On the contrary CB1 receptors on GABAergic neurons mediate the acquisition of passive avoidance, as the absence of CB1 on those neurons establishes a strong bias toward escape behavior.”

https://www.ncbi.nlm.nih.gov/pubmed/29104536

https://www.frontiersin.org/articles/10.3389/fnbeh.2017.00201/full

Parameters of the Endocannabinoid System as Novel Biomarkers in Sepsis and Septic Shock.

Posted on by

metabolites-logo

“Sepsis represents a dysregulated immune response to infection, with a continuum of severity progressing to septic shock. This dysregulated response generally follows a pattern by which an initial hyperinflammatory phase is followed by a state of sepsis-associated immunosuppression.

Major challenges in improving sepsis care include developing strategies to ensure early and accurate identification and diagnosis of the disease process, improving our ability to predict outcomes and stratify patients, and the need for novel sepsis-specific treatments such as immunomodulation.

Biomarkers offer promise with all three of these challenges and are likely also to be the solution to determining a patient’s immune status; something that is critical in guiding effective and safe immunomodulatory therapy. Currently available biomarkers used in sepsis lack sensitivity and specificity, among other significant shortcomings.

The endocannabinoid system (ECS) is an emerging topic of research with evidence suggesting a ubiquitous presence on both central and peripheral tissues, including an intrinsic link with immune function. This review will first discuss the state of sepsis biomarkers and lack of available treatments, followed by an introduction to the ECS and a discussion of its potential to provide novel biomarkers and treatments.”

https://www.ncbi.nlm.nih.gov/pubmed/29104224

http://www.mdpi.com/2218-1989/7/4/55

Maternal high-fat diet induces sex-specific endocannabinoid system changes in newborn rats and programs adiposity, energy expenditure and food preference in adulthood.

Posted on by

The Journal of Nutritional Biochemistry

“Early life inadequate nutrition triggers developmental adaptations and adult chronic disease.

Maternal high-fat (HF) diet promotes visceral obesity and hypothalamic leptin resistance in male rat offspring at weaning and adulthood.

Obesity is related to over active endocannabinoid system (ECS). The ECS consists mainly of endogenous ligands, cannabinoid receptors (CB1 and CB2), and the enzymes fatty acid anandamide hydrolase (FAAH) and monoacylglycerol lipase (MAGL).

We hypothesized that perinatal maternal HF diet would regulate offspring ECS in hypothalamus and brown adipose tissue (BAT) at birth, prior to visceral obesity development, and program food preference and energy expenditure of adult offspring.

In conclusion, maternal HF diet alters ECS components and energy metabolism targets in hypothalamus and BAT of offspring at birth, in a sex-specific manner, which may contribute for hyperphagia, food preference and higher adiposity later in life.”

https://www.ncbi.nlm.nih.gov/pubmed/29102876

http://www.sciencedirect.com/science/article/pii/S0955286317303042?via%3Dihub

Translating Endocannabinoid Biology into Clinical Practice: Cannabidiol for Stroke Prevention.

Posted on by

Mary Ann Liebert, Inc. publishers

“Introduction: The endocannabinoid system (ECS) regulates functions throughout human physiology, including neuropsychiatric, cardiovascular, autonomic, metabolic, and inflammatory states. The complex cellular interactions regulated by the ECS suggest a potential for vascular disease and stroke prevention by augmenting central nervous and immune cell endocannabinoid signaling.

Discussion: The endocannabinoid N-arachidonoylethanolamine (anandamide) plays a central role in augmenting these processes in cerebrovascular and neurometabolic disease. Furthermore, cannabidiol (CBD), a nonpsychoactive constituent of Cannabis, is an immediate therapeutic candidate both for potentiating endocannabinoid signaling and for acting at multiple pharmacological targets.

Conclusion: This speculative synthesis explores the current state of knowledge of the ECS and suggests CBD as a therapeutic candidate for stroke prevention by exerting favorable augmentation of the homeostatic effects of the ECS and, in turn, improving the metabolic syndrome, while simultaneously stalling the development of atherosclerosis.”

https://www.ncbi.nlm.nih.gov/pubmed/29098188
http://online.liebertpub.com/doi/10.1089/can.2017.0033

Review: The Role of Cannabinoids on Esophageal Function-What We Know Thus Far.

Posted on by

Mary Ann Liebert, Inc. publishers

“The endocannabinoid system (ECS) primarily consists of cannabinoid receptors (CBRs), endogenous ligands, and enzymes for endocannabinoid biosynthesis and inactivation. Although the presence of CBRs, both CB1 and CB2, as well as a third receptor (G-protein receptor 55 [GPR55]), has been established in the gastrointestinal (GI) tract, few studies have focused on the role of cannabinoids on esophageal function. To date, studies have shown their effect on GI motility, inflammation and immunity, intestinal and gastric acid secretion, nociception and emesis pathways, and appetite control. Given the varying and sometimes limited efficacy of current medical therapies for diseases of the esophagus, further understanding and investigation into the interplay of the ECS on esophageal health and disease may present new therapeutic modalities that may help advance current treatment options. In this brief review, the current understanding of the ECS role in various esophageal functions and disorders is presented.”

https://www.ncbi.nlm.nih.gov/pubmed/29098187

http://online.liebertpub.com/doi/10.1089/can.2017.0031

The endocannabinoid system and its therapeutic exploitation in multiple sclerosis: clues for other neuroinflammatory diseases.

Posted on by

Cover image

“Multiple sclerosis is the most common inflammatory demyelinating disease of the central nervous system, caused by an autoimmune response against myelin that eventually leads to progressive neurodegeneration and disability. Although the knowledge on its underlying neurobiological mechanisms has considerably improved, there is a still unmet need for new treatment options, especially for the progressive forms of the disease.

Both preclinical and clinical data suggest that cannabinoids, derived from the Cannabis sativa plant, may be used to control symptoms such as spasticity and chronic pain, whereas only preclinical data indicate that these compounds and their endogenous counterparts, i.e. the endocannabinoids, may also exert neuroprotective effects and slow down disease progression.

Here, we review the preclinical and clinical studies that could explain the therapeutic action of cannabinoid-based medicines, as well as the medical potential of modulating endocannabinoid signaling in multiple sclerosis, with a link to other neuroinflammatory disorders that share common hallmarks and pathogenetic features.”

https://www.ncbi.nlm.nih.gov/pubmed/29097192

http://www.sciencedirect.com/science/article/pii/S0301008217300709