Cannabinoid receptor interacting protein (CRIP1a) attenuates CB1R signaling in neuronal cells.

“CB1 cannabinoid receptors (CB1R) are one of the most abundantly expressed G protein coupled receptors (GPCR) in the CNS and regulate diverse neuronal functions.

The identification of GPCR interacting proteins has provided additional insight into the fine-tuning and regulation of numerous GPCRs.

The cannabinoid receptor interacting protein 1a (CRIP1a) binds to the distal carboxy terminus of CB1R, and has been shown to alter CB1R-mediated neuronal function.

The mechanisms by which CRIP1a regulates CB1R activity have not yet been identified; therefore the focus of this investigation is to examine the cellular effects of CRIP1a on CB1R signaling using neuronal N18TG2 cells stably transfected with CRIP1a over-expressing and CRIP1a knockdown constructs.

These studies suggest a mechanism by which endogenous levels of CRIP1a modulate CB1R-mediated signal transduction by facilitating a Gi/o protein subtype preference for Gi1 and Gi2, accompanied by an overall suppression of G-protein-mediated signaling in neuronal cells.”

http://www.ncbi.nlm.nih.gov/pubmed/25446256

Cannabinoid Receptor Interacting Protein (CRIP1a) suppresses agonist-driven CB1 receptor internalization, and regulates receptor replenishment in an agonist-biased manner.

“Cannabinoid Receptor Interacting Protein1a (CRIP1a) is a CB1 receptor (CB1 R) distal C-terminus-associated protein that modulates CB1 R signaling via G proteins, and CB1 R down-regulation but not desensitization.

In the present study, we determined the involvement of CRIP1a in CB1 R plasma membrane trafficking.

These studies demonstrate a novel role for CRIP1a in agonist-driven CB1 R cell surface regulation postulated to occur by two mechanisms: attenuating agonist-mediated but not internalization in the absence of exogenous agonists, and biased agonist-dependent trafficking of de novo synthesized receptor to the cell surface.”

http://www.ncbi.nlm.nih.gov/pubmed/27513693

Synthesis and Biological Evaluation of Thiophene-Based Cannabinoid Receptor Type 2 Radiotracers for PET Imaging.

“Over the past two decades, our understanding of the endocannabinoid system has greatly improved due to the wealth of results obtained from exploratory studies. Currently, two cannabinoid receptor subtypes have been well-characterized. The cannabinoid receptor type 1 (CB1) is widely expressed in the central nervous system, while the levels of the cannabinoid receptor type 2 (CB2) in the brain and spinal cord of healthy individuals are relatively low.”

http://www.ncbi.nlm.nih.gov/pubmed/27512365

Cross-validated stable-isotope dilution GC-MS and LC-MS/MS assays for monoacylglycerol lipase (MAGL) activity by measuring arachidonic acid released from the endocannabinoid 2-arachidonoyl glycerol.

“2-Arachidonoyl glycerol (2AG) is an endocannabinoid that activates cannabinoid (CB) receptors CB1 and CB2. Monoacylglycerol lipase (MAGL) inactivates 2AG through hydrolysis to arachidonic acid (AA) and glycerol, thus modulating the activity at CB receptors.” http://www.ncbi.nlm.nih.gov/pubmed/27511795

Marijuana users do not have increased healthcare utilization: A National Health and Nutrition Examination Survey (NHANES) study

“There is paucity of data on healthcare utilization due to marijuana use on a national scale.

Our study found no significant association exists between marijuana use and healthcare utilization.

The frequency of marijuana use also does not have significant impact on healthcare utilization.”

http://www.ejinme.com/article/S0953-6205(16)30231-X/fulltext

Effective treatment of spasticity using dronabinol in pediatric palliative care.

“Cannabis extracts have a wide therapeutic potential but in many countries they have not been approved for treatment in children so far.

We conducted an open, uncontrolled, retrospective study on the administration of dronabinol to determine the value, efficacy, and safety of cannabis-based medicines in the treatment of refractory spasticity in pediatric palliative care.

Sixteen children, adolescents and young adults having complex neurological conditions with spasticity (aged 1.3-26.6 years, median 12.7 years) were treated with dronabinol by our specialized pediatric palliative care team between 01.12.2010 and 30.04.2015 in a home-care setting. Therapeutic efficacy and side effects were closely monitored.

RESULTS:

Drops of the 2.5% oily tetrahydrocannabinol solution (dronabinol) were administered. A promising therapeutic effect was seen, mostly due to abolishment or marked improvement of severe, treatment resistant spasticity (n = 12). In two cases the effect could not be determined, two patients did not benefit. The median duration of treatment was 181 days (range 23-1429 days). Dosages to obtain a therapeutic effect varied from 0.08 to 1.0 mg/kg/d with a median of 0.33 mg/kg/d in patients with a documented therapeutic effect. When administered as an escalating dosage scheme, side effects were rare and only consisted in vomiting and restlessness (one patient each).

No serious and enduring side effects occurred even in young children and/or over a longer period of time.

CONCLUSIONS:

In the majority of pediatric palliative patients the treatment with dronabinol showed promising effects in treatment resistant spasticity.”

http://www.ncbi.nlm.nih.gov/pubmed/27506815

Pure Δ9-tetrahydrocannabivarin and a Cannabis sativa extract with high content in Δ9-tetrahydrocannabivarin inhibit nitrite production in murine peritoneal macrophages.

“Historical and scientific evidence suggests that Cannabis use has immunomodulatory and anti-inflammatory effects.

We have here investigated the effect of the non-psychotropic phytocannabinoid Δ9-tetrahydrocannabivarin (THCV) and of a Cannabis sativa extract with high (64.8%) content in THCV (THCV-BDS) on nitric oxide (NO) production, and on cannabinoid and transient receptor potential (TRP) channel expression in lipopolysaccharide (LPS)-stimulated murine peritoneal macrophages.

THCV-BDS and THCV exhibited similar affinity in radioligand binding assays for CB1 and CB2 receptors, and inhibited, via CB2 but not CB1 cannabinoid receptors, nitrite production evoked by LPS in peritoneal macrophages.

THCV down-regulated the over-expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and interleukin 1β (IL-1β) proteins induced by LPS.

Furthermore, THCV counteracted LPS-induced up-regulation of CB1 receptors, without affecting the changes in CB2, TRPV2 or TRPV4 mRNA expression caused by LPS. Other TRP channels, namely, TRPA1, TRPV1, TRPV3 and TRPM8 were poorly expressed or undetectable in both unstimulated and LPS-challenged macrophages.

It is concluded that THCV – via CB2 receptor activation – inhibits nitrite production in macrophages. The effect of this phytocannabinoid was associated with a down-regulation of CB1, but not CB2 or TRP channel mRNA expression.”

http://www.ncbi.nlm.nih.gov/pubmed/27498155

Cannabinoid signalling in TNF-alpha induced IL-8 release.

“The molecular events mediating the immunomodulatory properties of cannabinoids have remained largely unresolved.

We have therefore investigated the molecular mechanism(s) through which R-(+)-[2,3-dihydro-5-methyl-3-[(morpholinyl)methyl] pyrrolo[1,2,3-de]-1,4-benzoxazinyl]-(1-napthanlenyl) methanone (WIN55212-2) modulate production of interleukin-8 (IL-8) in HT-29 cells.

Release of IL-8 induced by tumor necrosis factor-alpha (TNF-alpha) was determined by enzyme-linked immunosorbent assay (ELISA). Changes in expression of inhibitory kappa B (IkappaB) were monitored by Western blotting and activation of nuclear factor-kappa B (NF-kappaB) was determined in electrophoretic mobility shift assay (EMSAs).

TNF-alpha induced release of IL-8 was inhibited by WIN55212-2 which also blocked the degradation of IkappaB-alpha and activation of NF-kappaB induced by TNF-alpha.

These data provide strong evidence that WIN55212-2 may modulate IL-8 release by negatively regulating the signaling cascade leading to the activation of NF-kappaB.

These findings highlight a potential mechanism for the immunomodulatory properties of cannabinoids and contribute towards acquiring a clear understanding of the role of cannabinoids in inflammation.”

http://www.ncbi.nlm.nih.gov/pubmed/16714014

“Essential involvement of interleukin-8 (IL-8) in acute inflammation.”  http://www.ncbi.nlm.nih.gov/pubmed/7964163

“Cannabinoids as novel anti-inflammatory drugs”  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2828614/

Endocannabinoids: new targets for drug development.

“The possible therapeutic use of marijuana s active principles, the cannabinoids, is currently being debated.

It is now known that these substances exert several of their pharmacological actions by activating specific cell membrane receptors, the CB1 and CB2 cannabinoid receptor subtypes.

This knowledge led to the design of synthetic cannabinoid agonists and antagonists with high therapeutic potential.

The recent discovery of the endocannabinoids, i.e. endogenous metabolites capable of activating the cannabinoid receptors, and the understanding of the molecular mechanisms leading to their biosynthesis and inactivation, opened a new era in research on the pharmaceutical applications of cannabinoids.

Ongoing studies on the pathological and physiological conditions regulating the tissue levels of endocannabinoids, and on the pharmacological activity of these compounds and their derivatives, may provide a lead for the development of new drugs for the treatment of nervous and immune disorders, cardiovascular diseases, pain, inflammation and cancer.

These studies are reviewed in this article with special emphasis on the chemical features that determine the interaction of endocannabinoids with the proteins mediating their activity and degradation.”

http://www.ncbi.nlm.nih.gov/pubmed/10903398