“The cannabinoid system exerts functional regulation of neural stem cell (NSC) proliferation and adult neurogenesis, yet not all effects of cannabinoid-like compounds seen can be attributed to the cannabinoid 1 receptor (CB1 R) or cannabinoid 2 receptor (CB2 R). The recently de-orphaned GPR55 has been shown to be activated by numerous cannabinoid ligands suggesting that GPR55 is a third cannabinoid receptor. Here we examined the role of GPR55 activation in NSC proliferation and early adult neurogenesis.
Author Archives: David Worrell
Probing the endocannabinoid system in healthy volunteers: Cannabidiol alters fronto-striatal resting-state connectivity.
“Tetrahydrocannabinol (THC) and Cannabidiol (CBD) are two substances from cannabis sativa that have been implicated in the treatment of mental and neurological disorders.
We concentrated on a previously validated neuroimaging phenotype, fronto-striatal connectivity across different striatal seeds, because of this loop’s relevance to executive functioning, decision making, salience generation and motivation and its link to various neuropsychiatric conditions. Therefore, we studied the effect of THC and CBD on fronto-striatal circuitry by a seed-voxel connectivity approach using seeds from the caudate and the putamen.
We conducted a cross-over pharmaco-fMRI study in 16 healthy male volunteers with placebo, 10 mg oral THC and 600 mg oral CBD. Resting state was measured in a 3 T scanner. CBD lead to an increase of fronto-striatal connectivity in comparison to placebo.
In contrast to our expectation that THC and CBD show opposing effects, THC versus placebo did not show any significant effects, probably due to insufficient concentration of THC during scanning.
The effect of CBD on enhancing fronto-striatal connectivity is of interest because it might be a neural correlate of its anti-psychotic effect in patients.”
A cannabinoid receptor 2 agonist reduces blood-brain barrier damage via induction of MKP-1 after intracerebral hemorrhage in rats.
“The blood-brain barrier (BBB) disruption and the following development of brain edema, is the most life-threatening secondary injury after intracerebral hemorrhage (ICH). This study is to investigate a potential role and mechanism of JWH133, a selected cannabinoid receptor type2 (CB2R) agonist, on protecting blood-brain barrier integrity after ICH.
CONCLUSIONS:
CB2R agonist alleviated neuroinflammation and protected blood-brain barrier permeability in a rat ICH model. Further molecular mechanisms revealed which is probably mediated by enhancing the expression of MKP-1, then inhibited MAPKs signal transduction.” https://www.ncbi.nlm.nih.gov/pubmed/29886251]]>The relationship of endocannabinoidome lipid mediators with pain and psychological stress in women with fibromyalgia – a case control study.
“Characterized by chronic widespread pain, generalized hyperalgesia, and psychological stress fibromyalgia (FM) is difficult to diagnose and lacks effective treatments. The endocannabinoids – arachidonoylethanolamide (AEA), 2-arachidonoylglycerol (2-AG), and the related oleoylethanolamide (OEA), palmitoylethanolamide (PEA), and stearoylethanolamide (SEA) – are endogenous lipid mediators with analgesic and anti-inflammatory characteristics, in company with psychological modulating properties (e.g., stress and anxiety), and are included in a new emerging “ome”, the endocannabinoidome. This case -control study compared the concentration differences of AEA, OEA, PEA, SEA, and 2-AG in 104 women with FM and 116 healthy controls (CON). All participants OEArated their pain, anxiety, depression, and current health status. The relationships between the lipid concentrations and the clinical assessments were investigated using powerful multivariate data analysis and traditional bivariate statistics. The concentrations of OEA, PEA, SEA, and 2-AG were significantly higher in FM than in CON; significance remained for OEA and SEA after controlling for BMI and age. 2-AG correlated positively with FM duration and BMI, and to some extent negatively with pain, anxiety, depression, and health status. In FM, AEA correlated positively with depression ratings. The elevated circulating levels of endocannabinoidome lipids suggest that these lipids play a role in the complex pathophysiology of FM and might be signs of ongoing low-grade inflammation in FM. Although the investigated lipids are significantly altered in FM their biological roles are uncertain with respect to the clinical manifestations of FM. Thus, plasma lipids alone are not good biomarkers for FM.
PERSPECTIVE:
This study reports about elevated plasma levels of endocannabinoidome lipid mediators in FM. The lipids suitability to work as biomarkers for FM in the clinic were low, however their altered levels indicate that a metabolic asymmetry is ongoing in FM, which could serve as basis during explorative FM pain management.” https://www.ncbi.nlm.nih.gov/pubmed/29885369 https://www.jpain.org/article/S1526-5900(18)30197-4/fulltext]]>Cannabinoid receptor type 1 in the brain regulates the affective component of visceral pain in mice.
“Endocannabinoids acting through cannabinoid receptor type 1 (CB1) are major modulators of peripheral somatic and visceral nociception. Although only partially studied, some evidence suggests a particular role of CB1 within the brain in nociceptive processes.
As the endocannabinoid system regulates affect and emotional behaviors, we hypothesized that cerebral CB1 influences affective processing of visceral pain-related behaviors in laboratory animals.
To study nocifensive responses modulated by supraspinal CB1, we used conditional knock-out mice lacking CB1 either in cortical glutamatergic neurons (Glu-CB1-KO), or in forebrain GABAergic neurons (GABA-CB1-KO), or in principle neurons of the forebrain (CaMK-CB1-KO). These mutant mice and mice treated with the CB1 antagonist SR141716 were tested for different pain-related behaviors. In an acetic acid-induced abdominal constriction test, supraspinal CB1 deletions did not affect nocifensive responses. In the cerulein-model of acute pancreatitis, mechanical allodynia or hyperalgesia were not changed, but Glu-CB1- and CaMK-CB1-KO mice showed significantly increased facial grimacing scores indicating increased affective responses to this noxious visceral stimulus. Similarly, these brain-specific CB1 KO mice also showed significantly changed thermal nociception in a hot-plate test.
These results reveal a novel, and important role of CB1 expressed by cortical glutamatergic neurons in the affective component of visceral nociception.”
https://www.ncbi.nlm.nih.gov/pubmed/29885522
“Cannabidiol (CBD) is a compound of 
“Depression associated with diabetes has been described as a highly debilitating comorbidity. Due to its complex and multifactorial mechanisms, the treatment of depression associated with diabetes represents a clinical challenge.
Cannabidiol (CBD), the non-psychotomimetic compound derived from 
“The 
“The endocannabinoid system (ECS) is composed of cannabinoid receptors, their endogenous ligands, and the enzymes involved in endocannabinoid turnover.
Modulating the activity of the ECS may influence a variety of physiological and pathophysiological processes.
A growing body of evidence indicates that activation of cannabinoid receptors by endogenous, plant-derived, or synthetic cannabinoids may exert beneficial effects on gastrointestinal inflammation and visceral pain.
The present ex vivo study aimed to investigate immunohistochemically the distribution of cannabinoid receptors CB1, CB2, G protein-coupled receptor 55 (GPR55), and peroxisome proliferation activation receptor alpha (PPARα) in the canine gastrointestinal tract.
Cannabinoid receptors showed a wide distribution in the gastrointestinal tract of the dog.
Since cannabinoid receptors have a protective role in inflammatory bowel disease, the present research provides an anatomical basis supporting the therapeutic use of cannabinoid receptor agonists in relieving motility disorders and visceral hypersensitivity in canine acute or chronic enteropathies.”