Synergistic action of CB1 and 5-HT2B receptors in preventing pilocarpine-induced status epilepticus in rats.

Neurobiology of Disease

“Endocannabinoids (eCBs) and serotonin (5-HT) play a neuromodulatory role in the central nervous system. Both eCBs and 5-HT regulate neuronal excitability and their pharmacological potentiation has been shown to control seizures in pre-clinical and human studies.

Compelling evidence indicates that eCB and 5-HT systems interact to modulate several physiological and pathological brain functions, such as food intake, pain, drug addiction, depression, and anxiety.

Nevertheless, there is no evidence of an eCB/5-HT interaction in experimental and human epilepsies, including status epilepticus (SE). Here, we performed video-EEG recording in behaving rats treated with the pro-convulsant agent pilocarpine (PILO), in order to study the effect of the activation of CB1/5-HT2receptors and their interaction on SE.

Synthetic cannabinoid agonist WIN55,212-2 (WIN) decreased behavioral seizure severity of PILO-induced SE at 2 mg/kg (but not at 1 and 5 mg/kg, i.p.), while 5-HT2B/2C receptor agonist RO60-0175 (RO; 1, 3, 10 mg/kg, i.p.) was devoid of any effect. RO 3 mg/kg was instead capable of potentiating the effect of WIN 2 mg/kg on the Racine scale score.

Surprisingly, neither WIN 2 mg/kg nor RO 3 mg/kg had any effect on the incidence and the intensity of EEG seizures when administered alone. However, WIN+RO co-administration reduced the incidence and the severity of EEG SE and increased the latency to SE onset after PILO injection. WIN+RO effects were blocked by the selective CB1R antagonist AM251 and the 5-HT2BR antagonist RS127445, but not by the 5-HT2CR antagonist SB242084 or the 5-HT2AR antagonist MDL11,939.

These data revealed a synergistic interaction between CB1R/5-HT2BR in the expression of PILO-induced SE.”

https://www.ncbi.nlm.nih.gov/pubmed/30716469

https://www.sciencedirect.com/science/article/pii/S0969996119300336?via%3Dihub

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Ketamine induces central antinociception mediated by endogenous cannabinoids and activation of CB1 receptors.

Neuroscience Letters

“The participation of endocannabinoids in central and peripheral antinociception induced by several compounds has been shown by our group.

In this study, we investigated the effect of endocannabinoids on the central antinociception induced by ketamine.

It was concluded that central antinociception induced by ketamine involves the activation of CB1 cannabinoidreceptors.

Mobilization of cannabinoids might be required for the activation of those receptors, since inhibitors of the endogenous cannabinoids potentiate the effect of Ketamine.”

https://www.ncbi.nlm.nih.gov/pubmed/30716423

https://www.sciencedirect.com/science/article/abs/pii/S0304394019300771?via%3Dihub

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Synthetic Cannabinoids Influence the Invasion of Glioblastoma Cell Lines in a Cell- and Receptor-Dependent Manner.

cancers-logo

“The current treatment of glioblastoma is not sufficient, since they are heterogeneous and often resistant to chemotherapy.

Earlier studies demonstrated effects of specific cannabinoid receptor (CB) agonists on the invasiveness of glioblastoma cell lines, but the exact mechanism remained unclear.

Three human glioblastoma cell lines were treated with synthetic CB ligands. The effect of cannabinoids on microRNAs (miRs), Akt, and on the expression of proliferation and apoptosis markers were analyzed.

Furthermore, in a model of organotypic hippocampal slice cultures cannabinoid mediated changes in the invasiveness were assessed. MicroRNAs and the activation of Akt which are related to cell migration, apoptosis, and proliferation were evaluated and found not to be associated with changes in the invasiveness after treatment with CB ligands.

Also proliferation and/or apoptosis were not altered after treatment. The effects of cannabinoids on invasiveness could be blocked by the application of receptor antagonists and are likely mediated via CB₁/CB₂.

In conclusion, our results suggest that cannabinoids can influence glioblastoma cell invasion in a receptor and cell type specific manner that is independent of proliferation and apoptosis. Thus, cannabinoids can potentially be used in the future as an addition to current therapy.”

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Opposite effects of cannabinoid CB1 and CB2 receptors on antipsychotic clozapine-induced cardiotoxicity.

Publication cover image

“Clozapine is an atypical antipsychotic drug that is very efficacious in treating psychosis but the risk of severe cardiotoxicity limits its clinical use.

The present study investigated the myocardial injury effects of clozapine and assessed the involvement of cannabinoid receptors in clozapine cardiotoxicity.

Our data provided evidence that cannabinoid CB1 and CB2 receptors had opposite effects and selective antagonists of CB1R or agonists of CB2R might confer protective effects against clozapine.”

https://www.ncbi.nlm.nih.gov/pubmed/30707759

https://bpspubs.onlinelibrary.wiley.com/doi/abs/10.1111/bph.14591

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Activation of the cannabinoid CB2 receptor increases renal perfusion.

Physiological Genomics 0 0 cover image

“Acute kidney injury (AKI) is an increasing problem clinically and is associated with chronic kidney disease progression.

Cannabinoid type 2 receptor activation has been shown to mitigate some of the deleterious tubular effects due to AKI, but its role on the renal vasculature has not been fully described.

In this study, we investigated the effects of our novel cannabinoid CB2 receptor agonist, SMM-295, on renal vasculature by assessing cortical perfusion using laser Doppler flowmetry and changes in luminal diameter using isolated afferent arterioles.

These data provide new insight into the potential benefit of SMM-295 by activating vascular and non-vascular CB2 receptors to promote renal vasodilation, and provide a new therapeutic target to treat renal injuries that impact renal blood flow dynamics.”

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Is cannabidiol the ideal drug to treat non-motor Parkinson’s disease symptoms?

 “Parkinson’s disease (PD) is a chronic neurodegenerative disorder characterized by motor symptoms such as bradykinesia, rest tremor, postural disturbances, and rigidity. PD is also characterized by non-motor symptoms such as sleep disturbances, cognitive deficits, and psychiatric disorders such as psychosis, depression, and anxiety. The pharmacological treatment for these symptoms is limited in efficacy and induce significant adverse reactions, highlighting the need for better treatment options.

Cannabidiol (CBD) is a phytocannabinoid devoid of the euphoriant and cognitive effects of tetrahydrocannabinol, and preclinical and preliminary clinical studies suggest that this compound has therapeutic effect in non-motor symptoms of PD.

In the present text, we review the clinical studies of cannabinoids in PD and the preclinical and clinical studies specifically on CBD.

We found four randomized controlled trials (RCTs) involving the administration of agonists/antagonists of the cannabinoid 1 receptor, showing that these compounds were well tolerated, but only one study found positive results (reductions on levodopa-induced dyskinesia).

We found seven preclinical models of PD using CBD, with six studies showing a neuroprotective effect of CBD.

We found three trials involving CBD and PD: an open-label study, a case series, and an RCT. CBD was well tolerated, and all three studies reported significant therapeutic effects in non-motor symptoms (psychosis, rapid eye movement sleep behaviour disorder, daily activities, and stigma). However, sample sizes were small and CBD treatment was short (up to 6 weeks). Large-scale RCTs are needed to try to replicate these results and to assess the long-term safety of CBD.”

https://www.ncbi.nlm.nih.gov/pubmed/30706171

https://link.springer.com/article/10.1007%2Fs00406-019-00982-6

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Potential Use of Cannabinoids for the Treatment of Pancreatic Cancer.

Image result for Journal Pancreatic Cancer

Cannabinoid extracts may have anticancer properties, which can improve cancer treatment outcomes.

The aim of this review is to determine the potentially utility of cannabinoids in the treatment of pancreatic cancer.

Results: Cannabinol receptors have been identified in pancreatic cancer with several studies showing in vitroantiproliferative and proapoptotic effects. The main active substances found in cannabis plants are cannabidiol (CBD) and tetrahydrocannabinol (THC). There effects are predominately mediated through, but not limited to cannabinoid receptor-1, cannabinoid receptor-2, and G-protein-coupled receptor 55 pathways. In vitro studies consistently demonstrated tumor growth-inhibiting effects with CBD, THC, and synthetic derivatives. Synergistic treatment effects have been shown in two studies with the combination of CBD/synthetic cannabinoid receptor ligands and chemotherapy in xenograft and genetically modified spontaneous pancreatic cancer models. There are, however, no clinical studies to date showing treatment benefits in patients with pancreatic cancer.

Conclusions: Cannabinoids may be an effective adjunct for the treatment of pancreatic cancer. Data on the anticancer effectiveness of various cannabinoid formulations, treatment dosing, precise mode of action, and clinical studies are lacking.”

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Cannabinoids and Bone Regeneration.

 Publication Cover“Bone is a complex tissue of the with unique properties such as high strength and regeneration capabilities while carrying out multiple functions. Bone regeneration occurs both in physiological situations (bone turnover) and pathological situations (e.g. fractures), being performed by osteoblasts and osteoclasts. If this process is inadequate, fracture nonunion or aseptic loosening of implants occurs and requires a complex treatment.

Exogenous factors are currently used to increase bone regeneration process when needed, such as bisphosphonates and vitamin D, but limitations do exist. Cannabinoid system has been shown to have positive effects on bone metabolism. Cannabinoids at bone level mainly act on two receptors called CB-1 and CB-2, but GPR55, GPR119, TPRV1, TPRV4 receptors may also be involved. The CB-2 receptors are found in bone cells at higher levels compared to other receptors.

Endocannabinods represented by anandamide and 2-arachidonoylglycerol, can stimulate osteoblast formation, bone formation and osteoclast activity. CB-2 agonists including HU-308, HU-433, JWH133 and JWH015 can stimulate osteoblast proliferation and activity, while CB-2 antagonists such as AM630 and SR144528 can inhibit osteoclast differentiation and function. CB-1 antagonist AM251 has been shown to inhibit osteoclast differentiation and activity, while GPR55 antagonist cannabidiol increases osteoblast activity and decreases osteoclast function.

An optimal correlation of dose, duration, moment of action and affinity can lead to an increased bone regeneration capacity, with important benefits in many pathological situations which involve bone tissue. As adverse reactions of cannabinoids haven’t been described in patients under controlled medication, cannabinoids can represent future treatment for bone regeneration.”

https://www.ncbi.nlm.nih.gov/pubmed/30702341

https://www.tandfonline.com/doi/abs/10.1080/03602532.2019.1574303?journalCode=idmr20

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Diet-Induced Obesity in Cannabinoid-2 Receptor Knockout Mice and Cannabinoid Receptor 1/2 Double-Knockout Mice.

Obesity banner

“Evidence suggests that cannabinoid-1 receptor (CB1R) activation is associated with increased food intake and body weight gain. Human epidemiological studies, however, show decreased prevalence of obesity in cannabis users.

Given the overlapping and complementary functions of the cannabinoid receptors (CB1R and CB2R), mice lacking CB2R and mice lacking both CB1R and CB2R were studied.

These results indicate that lacking both CB1R and CB2R protected mice from diet-induced obesity, possibly through the prominent role of CB1R in obesity or through an interactive effect of both receptors.”

https://www.ncbi.nlm.nih.gov/pubmed/30699233

https://onlinelibrary.wiley.com/doi/abs/10.1002/oby.22403

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous

Cannabinoid Ligands Targeting TRP Channels.

Image result for frontiers in molecular neuroscience

“Many diseases involve Transient receptor potential (TRP) channel dysfunction, including neuropathic pain, inflammation, and respiratory disorders. In the pursuit of new treatments for these disorders, it was discovered that cannabinoids can modulate a certain subset of TRP channels. The TRP vanilloid (TRPV), TRP ankyrin (TRPA), and TRP melastatin (TRPM) subfamilies were all found to contain channels that can be modulated by several endogenous, phytogenic, and synthetic cannabinoids. To date, six TRP channels from the three subfamilies mentioned above have been reported to mediate cannabinoid activity: TRPV1, TRPV2, TRPV3, TRPV4, TRPA1, and TRPM8. The increasing data regarding cannabinoid interactions with these receptors has prompted some researchers to consider these TRP channels to be “ionotropic cannabinoid receptors.””

https://www.ncbi.nlm.nih.gov/pubmed/30697147

https://www.frontiersin.org/articles/10.3389/fnmol.2018.00487/full

Facebook Twitter Pinterest Stumbleupon Tumblr Posterous