“Displacement binding assays are nonfunctional assays mostly used with the aim of determining whether a certain compound (plant-derived or synthetic) is able to bind to a specific receptor with high affinity. Here, we describe the displacement binding assay that is carried out with a radioligand and CHO (Chinese Hamster Ovarian) cells stably transfected with the human cannabinoid CB2 receptor.”
Category Archives: Endocannabinoid System
Assay of CB1 Receptor Binding.
“Type-1 cannabinoid receptor (CB1), one of the main targets of endocannabinoids, plays a key role in several pathophysiological conditions that affect both central nervous system and peripheral tissues. Today, its biochemical identification and pharmacological characterization, as well as the screening of thousands of novel ligands that might be useful for developing CB1-based therapies, are the subject of intense research. Among available techniques that allow the analysis of CB1 binding activity, radioligand-based assays represent one of the best, fast, and reliable methods.Here, we describe radioligand binding methods standardized in our laboratory to assess CB1 binding in both tissues and cultured cells. We also report a high-throughput radioligand binding assay that allows to evaluate efficacy and potency of different compounds, which might represent the basis for the development of new drugs that target CB1 receptor-dependent human diseases.”
Need for Methods to Investigate Endocannabinoid Signaling.
“Endocannabinoids (eCBs) are endogenous lipids able to activate cannabinoid receptors, the primary molecular targets of the cannabis (Cannabis sativa) active principle Δ(9)-tetrahydrocannabinol. During the last 20 years, several N-acylethanolamines and acylesters have been shown to act as eCBs, and a complex array of receptors, metabolic enzymes, and transporters (that altogether form the so-called eCB system) has been shown to finely tune their manifold biological activities. It appears now urgent to develop methods and protocols that allow to assay in a specific and quantitative manner the distinct components of the eCB system, and that can properly localize them within the cell. A brief overview of eCBs and of the proteins that bind, transport, and metabolize these lipids is presented here, in order to put in a better perspective the relevance of methodologies that help to disclose molecular details of eCB signaling in health and disease. Proper methodological approaches form also the basis for a more rationale and effective drug design and therapeutic strategy to combat human disorders.”
Endocannabinoid system: a promising therapeutic target for the treatment of haematological malignancies?
“The therapeutic properties of cannabinoids are well-known since ancient years.
Growing evidence exist on endocannabinoid system (ECS) modulation related with human tumorigenesis.
Taking into account the substantial role of ECS on immune cell regulation, the present review is aimed to summarize the emerging evidence concerning cannabinoid receptor (CBR) expression and cannabinoid ligand effects on haematological malignancies.
CONCLUSIONS:
Most of cannabinoid actions, mainly CB2R-mediated against haematopoietic malignant cells, seems promising, as inhibition of cell proliferation and apoptosis and paraptosis induction have been documented.
Cannabinoid ligands appear to activate rudimentary pathways for cell survival, such as ERK, JNK, p38 MAPK, and to induce caspase synthesis, in vitro. Such data are strongly recommended to be confirmed by in vivo experiments with emphasis on cannabinoid ligands’ bioavailability and phytocannabinoid psychotropic properties.
The preliminary antitumoral ECS effects and their relative lack of important side effects render ECS a promising therapeutic target for the treatment of haematological malignancies.”
Endocannabinoid Modulation of Orbitostriatal Circuits Gates Habit Formation.
“Everyday function demands efficient and flexible decision-making that allows for habitual and goal-directed action control. An inability to shift has been implicated in disorders with impaired decision-making, including obsessive-compulsive disorder and addiction. Despite this, our understanding of the specific molecular mechanisms and circuitry involved in shifting action control remains limited. Here we identify an endogenous molecular mechanism in a specific cortical-striatal pathway that mediates the transition between goal-directed and habitual action strategies. Deletion of cannabinoid type 1 (CB1) receptors from cortical projections originating in the orbital frontal cortex (OFC) prevents mice from shifting from goal-directed to habitual instrumental lever pressing. Activity of OFC neurons projecting to dorsal striatum (OFC-DS) and, specifically, activity of OFC-DS terminals is necessary for goal-directed action control. Lastly, CB1 deletion from OFC-DS neurons prevents the shift from goal-directed to habitual action control. These data suggest that the emergence of habits depends on endocannabinoid-mediated attenuation of a competing circuit controlling goal-directed behaviors.”
Cannabinoid receptor type-1: breaking the dogmas.
“The endocannabinoid system (ECS) is abundantly expressed in the brain. This system regulates a plethora of physiological functions and is composed of cannabinoid receptors, their endogenous ligands (endocannabinoids), and the enzymes involved in the metabolism of endocannabinoids. In this review, we highlight the new advances in cannabinoid signaling, focusing on a key component of the ECS, the type-1cannabinoid receptor (CB 1). In recent years, the development of new imaging and molecular tools has demonstrated that this receptor can be distributed in many cell types (e.g., neuronal or glial cells) and intracellular compartments (e.g., mitochondria). Interestingly, cellular and molecular effects are differentially mediated by CB 1 receptors according to their specific localization (e.g., glutamatergic or GABAergic neurons). Moreover, this receptor is expressed in the periphery, where it can modulate periphery-brain connections. Finally, the better understanding of the CB 1 receptor structure led researchers to propose interesting and new allosteric modulators. Thus, the advances and the new directions of the CB 1 receptor field will provide new insights and better approaches to profit from its interesting therapeutic profile.”
Opioid withdrawal suppression efficacy of oral dronabinol in opioid dependent humans.
:”The cannabinoid (CB) system is a rational novel target for treating opioid dependence, a significant public health problem around the world. This proof-of-concept study examined the potential efficacy of a CB1 receptor partial agonist, dronabinol, in relieving signs and symptoms of opioid withdrawal.
CONCLUSION:
CB1 receptor activation is a reasonable strategy to pursue for the treatment of opioid withdrawal; however, dronabinol is not a likely candidate given its modest withdrawal suppression effects of limited duration and previously reported tachycardia during opioid withdrawal.”
Activation of endocannabinoid system in the rat basolateral amygdala improved scopolamine-induced memory consolidation impairment.
“The current study was designed to examine the involvement of cannabinoid CB1 receptors in the basolateral amygdala (BLA) in scopolamine-induced memory impairment in adult male Wistar rats.
In view of the known actions of the drugs used, the present data pointed to the involvement of the BLA CB1 receptors in scopolamine-induced memory consolidation impairment.
Furthermore, it seems that a functional interaction between the BLA endocannabinoid and cholinergic muscarinic systems may be critical for memory formation.”
http://www.ncbi.nlm.nih.gov/pubmed/27230394
“The most dangerous drug in the world: ‘Devil’s Breath’ chemical from Colombia can block free will, wipe memory and even kill. Scopolamine often blown into faces of victims or added to drinks. Within minutes, victims are like ‘zombies’ – coherent, but with no free will. Drug is made from borrachero tree, which is common in Colombia” http://www.dailymail.co.uk/news/article-2143584/Scopolamine-Powerful-drug-growing-forests-Colombia-ELIMINATES-free-will.html
“Activation of endocannabinoid system in the rat basolateral amygdala improved scopolamine-induced memory consolidation impairment.” http://www.ncbi.nlm.nih.gov/pubmed/27230394
Cannabinoids inhibit fibrogenesis in diffuse systemic sclerosis fibroblasts.
“Recently, it has also been demonstrated that the pleiotropic cannabinoid system is involved in both liver and pancreatic fibrosis. Furthermore, cannabinoids may play a pro- or anti-fibrogenic role depending on their interaction with CB1r or CB2r.
This raises the possibility that pharmacologic modulation of the endocannabinoid system could be a target to limit tissue damage in pathologic fibrosis.
It has been demonstrated that the endocannabinoid system is up-regulated in pathologic fibrosis and that modulation of the cannabinoid receptors might limit the progression of uncontrolled fibrogenesis.
Both CB1 and CB2 receptors were over-expressed in dcSSc fibroblasts compared with healthy controls.
Our preliminary findings suggest that cannabinoids are provided with an anti-fibrotic activity, thereby possibly representing a new class of agents targeting fibrosis diseases.”
http://rheumatology.oxfordjournals.org/content/48/9/1050.long
Cannabinoid receptor 2 (CB2) agonists and antagonists: a patent update.
“Modulation of the CB2 receptor is an interesting approach for pain and inflammation, arthritis, addictions, neuroprotection, and cancer, among other possible therapeutic applications, and is devoid of central side effects.