The multiplicity of action of cannabinoids: implications for treating neurodegeneration.

Posted on April 17, 2016 by David

“The cannabinoid (CB) system is widespread in the central nervous system and is crucial for controlling a range of neurophysiological processes such as pain, appetite, and cognition. The endogenous CB molecules, anandamide, and 2-arachidonoyl glycerol, interact with the G-protein coupled CB receptors, CB(1) and CB(2).

These receptors are also targets for the phytocannabinoids isolated from the cannabis plant and synthetic CB receptor ligands.

The CB system is emerging as a key regulator of neuronal cell fate and is capable of conferring neuroprotection by the direct engagement of prosurvival pathways and the control of neurogenesis.

Many neurological conditions feature a neurodegenerative component that is associated with excitotoxicity, oxidative stress, and neuroinflammation, and certain CB molecules have been demonstrated to inhibit these events to halt the progression of neurodegeneration.

Such properties are attractive in the development of new strategies to treat neurodegenerative conditions of diverse etiology, such as Alzheimer’s disease, multiple sclerosis, and cerebral ischemia.

This article will discuss the experimental and clinical evidence supporting a potential role for CB-based therapies in the treatment of certain neurological diseases that feature a neurodegenerative component.”

http://www.ncbi.nlm.nih.gov/pubmed/20875047

MAPPING CANNABINOID RECEPTOR 1 ALLOSTERIC SITE(S): CRITICAL MOLECULAR DETERMINANT AND SIGNALING PROFILE OF GAT100 – A NOVEL, POTENT AND IRREVERSIBLY BINDING PROBE.

Posted on April 6, 2016 by David

“One of the most abundant G-protein coupled receptors (GPCRs) in brain, the cannabinoid 1 receptor (CB1R) is a tractable therapeutic target for treating diverse psychobehavioral and somatic disorders.

Adverse on-target effects associated with small-molecule CB1R orthosteric agonists and inverse agonists/antagonists have plagued their translational potential. Allosteric CB1R modulators offer a potentially safer modality through which CB1R signaling may be directed for therapeutic benefit.

Rational design of candidate, drug-like CB1R allosteric modulators requires greater understanding of the architecture of the CB1R allosteric endodomain(s) and the capacity of CB1R allosteric ligands to tune the receptor’s information output.

These data help inform the engineering of newer-generation, druggable CB1R allosteric modulators and demonstrate the utility of GAT100 as a covalent probe for mapping structure-function correlates characteristic of the druggable CB1R allosteric space.”

http://www.ncbi.nlm.nih.gov/pubmed/27046127

No more pain upon Gq-protein-coupled receptor activation: role of endocannabinoids.

Posted on April 6, 2016 by David

“Marijuana has been used to relieve pain for centuries.

The analgesic mechanism of its constituents, the cannabinoids, was only revealed after the discovery of cannabinoid receptors (CB1 and CB2) two decades ago.”

http://www.ncbi.nlm.nih.gov/pubmed/24494686

Endocannabinoids and Endocannabinoid-Related Mediators: Targets, Metabolism and Role In Neurological Disorders.

Posted on March 12, 2016 by David

“The endocannabinoid system (ECS) is composed of two G protein-coupled receptors (GPCRs), the cannabinoid CB1 and CB2 receptors, and the two main endogenous lipid ligands of such receptors (also known as the “endocannabinoids”), anandamide and 2-arachidonoyl-glycerol. The ECS is a pleiotropic signalling systems involved in all aspects of mammalian physiology and pathology, and for this reason it represents a potential target for the design and development of new therapeutic drugs. However, the endocannabinoids as well as some of their congeners also interact with a much wider range of receptors, including members of the Transient Receptor Potential (TRP) channels, Peroxisome Proliferator-Activated Receptors (PPARs), and other GPCRs. Indeed, following the discovery of the endocannabinoids, endocannabinoid-related lipid mediators, which often share the same metabolic pathways of the endocannabinoids, have also been identified or rediscovered. In this review article, we discuss the role of endocannabinoids and related lipids during physiological functions, as well as their involvement is some of the most common neurological disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/26965148

A Single Intrathecal or Intraperitoneal Injection of CB2 Receptor Agonist Attenuates Bone Cancer Pain and Induces a Time-Dependent Modification of GRK2.

Posted on March 5, 2016 by David

“The objective of this study was to explore the potential role of G-protein-coupled receptor kinase 2 (GRK2) in the progression of cannabinoid 2 receptor (CB2) agonist-induced analgesic effects of bone cancer pain.

The results affirmed CB2 receptor agonists might serve as new treatment targets for bone cancer pain.

Moreover, spinal GRK2 was an important regulator of CB2 receptor agonist-analgesia pathway.”

http://www.ncbi.nlm.nih.gov/pubmed/26935064

The endocannabinoid system: a new approach to control cardiovascular disease.

Posted on February 20, 2016 by David

“The endocannabinoid (EC) system consists of 2 types of G-protein-coupled cannabinoid receptors–cannabinoid type 1 (CB1) and cannabinoid type 2 (CB2)–and their natural ligands.

The EC system plays a key role in the regulation of food intake and fat accumulation, as well as glucose and lipid metabolism.

When overactivated, the EC system triggers dyslipidemia, thrombotic and inflammatory states, and insulin resistance.

Blocking CB1 receptors centrally and peripherally in adipose tissue can help normalize an overactivated EC system. CB1 blockade helps regulate food intake and adipose tissue metabolism, contributing to improved insulin sensitivity and other features of the metabolic syndrome.

Visceral adipose tissue is most closely associated with the metabolic syndrome, which is a constellation of conditions that place people at high risk for coronary artery disease.

Targeting the EC system represents a new approach to treating visceral obesity and reducing cardiovascular risk factors.”

http://www.ncbi.nlm.nih.gov/pubmed/16473257

http://www.thctotalhealthcare.com/category/cardiovascular-disease/

Simultaneous Activation of Induced Heterodimerization between CXCR4 Chemokine Receptor and Cannabinoid Receptor 2 (CB2) Reveal a Mechanism for Regulation of Tumor Progression.

Posted on February 5, 2016 by David

“The G-protein-coupled chemokine receptor, CXCR4, generates signals that lead to cell migration, cell proliferation, and other survival mechanisms which result in the metastatic spread of primary tumor cells to distal organs.

Numerous studies have demonstrated that CXCR4 can form homodimers, or can heterodimerize with other GPCRs to form receptor complexes that can amplify or decrease the signaling capacity of each individual receptor.

Using biophysical and biochemical approaches, we found that CXCR4 can form an induced heterodimer with cannabinoid receptor 2 (CB2) in human breast and prostate cancer cells.

Simultaneous, agonist-dependent activation of CXCR4 and CB2 resulted in reduced CXCR4-mediated expression of phosphorylated ERK1/2, and ultimately, reduced cancer cell functions such as calcium mobilization and cellular chemotaxis.

Given that treatment with cannabinoids has been shown to reduce invasiveness of cancer cells, as well as CXCR4-mediated migration of immune cells, it is therefore plausible that CXCR4 signaling can be silenced through a physical heterodimeric association with CB2, thereby inhibiting subsequent functions of CXCR4.

Taken together, the data illustrates a mechanism by which the cannabinoid system can negatively modulate CXCR4 receptor function, and perhaps, tumor progression.”

http://www.ncbi.nlm.nih.gov/pubmed/26841863

Expression and Function of the Endocannabinoid System in the Retina and the Visual Brain.

Posted on February 4, 2016 by David

“Endocannabinoids are important retrograde modulators of synaptic transmission throughout the nervous system.

Cannabinoid receptors are seven transmembrane G-protein coupled receptors favoring Gi/o protein. They are known to play an important role in various processes, including metabolic regulation, craving, pain, anxiety, and immune function.

In the last decade, there has been a growing interest for endocannabinoids in the retina and their role in visual processing.

The purpose of this review is to characterize the expression and physiological functions of the endocannabinoid system in the visual system, from the retina to the primary visual cortex, with a main interest regarding the retina, which is the best-described area in this system so far.

It will show that the endocannabinoid system is widely present in the retina, mostly in the through pathway where it can modulate neurotransmitter release and ion channel activity, although some evidence also indicates possible mechanisms via amacrine, horizontal, and Müller cells.

The presence of multiple endocannabinoid ligands, synthesizing and catabolizing enzymes, and receptors highlights various pharmacological targets for novel therapeutic application to retinal diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/26839718

Cannabinoid receptor 2 and its agonists mediate hematopoiesis and hematopoietic stem and progenitor cell mobilization.

Posted on January 30, 2016 by David

“Endocannabinoids are arachidonic acid derivatives and part of a novel bioactive lipid signaling system, along with their G-coupled cannabinoid receptors (CB₁ and CB₂) and the enzymes involved in their biosynthesis and degradation.

However, their roles in hematopoiesis and hematopoietic stem and progenitor cell (HSPC) functions are not well characterized. Here, we show that bone marrow stromal cells express endocannabinoids (anandamide and 2-arachidonylglycerol), whereas CB₂ receptors are expressed in human and murine HSPCs.

On ligand stimulation with CB₂ agonists, CB₂ receptors induced chemotaxis, migration, and enhanced colony formation of bone marrow cells, which were mediated via ERK, PI3-kinase, and Gαi-Rac1 pathways.

Taken together, these results demonstrate that the endocannabinoid system is involved in hematopoiesis and that CB₂/CB₂ agonist axis mediates repopulation of hematopoiesis and mobilization of HSPCs.

Thus, CB₂ agonists may be therapeutically applied in clinical conditions, such as bone marrow transplantation.”

http://www.ncbi.nlm.nih.gov/pubmed/21063029

RGS proteins as targets in the treatment of intestinal inflammation and visceral pain: New insights and future perspectives.

Posted on January 29, 2016 by David

“Regulators of G protein signaling (RGS) proteins provide timely termination of G protein-coupled receptor (GPCR) responses. Serving as a central control point in GPCR signaling cascades, RGS proteins are promising targets for drug development. In this review, we discuss the involvement of RGS proteins in the pathophysiology of the gastrointestinal inflammation and their potential to become a target for anti-inflammatory drugs. Specifically, we evaluate the emerging evidence for modulation of selected receptor families: opioid, cannabinoid and serotonin by RGS proteins. We discuss how the regulation of RGS protein level and activity may modulate immunological pathways involved in the development of intestinal inflammation. Finally, we propose that RGS proteins may serve as a prognostic factor for survival rate in colorectal cancer. The ideas introduced in this review set a novel conceptual framework for the utilization of RGS proteins in the treatment of gastrointestinal inflammation, a growing major concern worldwide.”

http://www.ncbi.nlm.nih.gov/pubmed/26817719