Activation of cannabinoid CB1 receptors suppresses the ROS-induced hypersensitivity of rat vagal lung C-fiber afferents.

“Reactive oxygen species (ROS), including H2O2, have been shown to induce hypersensitivity of vagal lung C-fibers (VLCFs) mainly through receptor potential ankyrin 1 (TRPA1) and P2X receptors.

Cannabinoids (CBs) exert antinociceptive effects by binding to specific CB receptors, designated CB1 and CB2 (type 2) for type 1 and type 2, respectively.

We investigated whether activation of CB receptors can suppress ROS-mediated VLCF hypersensitivity and, if so, what type(s) of CB receptors are involved.

:Our results suggest that activation of CB1 receptors may suppress the ROS-mediated VLCF hypersensitivity through a mechanism that is at least partly distinct from the function of TRPA1 and P2X receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/27328978

Basolateral amygdala CB1 cannabinoid receptors are involved in cross state-dependent memory retrieval between morphine and ethanol.

“Ethanol and morphine are largely co-abused and affect memory formation.

The present study intended to investigate the involvement of cannabinoid CB1 receptors of the basolateral amygdala (BLA) in cross state-dependent memory retrieval between morphine and ethanol.

Taken together, it can be concluded that morphine and ethanol can induce state-dependent memory retrieval.

In addition, the BLA endocannabinoid system mediates via CB1 receptors the functional interaction of morphine and ethanol state-dependent memory retrieval which may depend on the rewarding effects of the drugs.”

http://www.ncbi.nlm.nih.gov/pubmed/27327764

The multiplicity of spinal AA-5-HT anti-nociceptive action in a rat model of neuropathic pain.

“There is considerable evidence to support the role of anandamide (AEA), an endogenous ligand of cannabinoid receptors, in neuropathic pain modulation. AEA also produces effects mediated by other biological targets, of which the transient receptor potential vanilloid type 1 (TRPV1) has been the most investigated. Both, inhibition of AEA breakdown by fatty acid amide hydrolase (FAAH) and blockage of TRPV1 have been shown to produce anti-nociceptive effects.

Recent research suggests the usefulness of dual-action compounds, which may afford greater anti-allodynic efficacy. Therefore, in the present study, we examined the effect of N-arachidonoyl-serotonin (AA-5-HT), a blocker of FAAH and TRPV1, in a rat model of neuropathic pain after intrathecal administration.

We found that treatment with AA-5-HT increased the pain threshold to mechanical and thermal stimuli, with highest effect at the dose of 500nM, which was most strongly attenuated by AM-630, CB2 antagonist, administration. The single action blockers PF-3845 (1000nM, for FAAH) and I-RTX (1nM, for TRPV1) showed lower efficacy than AA-5-HT. Moreover AA-5-HT (500nM) elevated AEA and palmitoylethanolamide (PEA) levels.

Among the possible targets of these mediators, only the mRNA levels of CB2, GPR18 and GPR55, which are believed to be novel cannabinoid receptors, were upregulated in the spinal cord and/or DRG of CCI rats. It was previously reported that AA-5-HT acts in CB1 and TRPV1-dependent manner after systemic administration, but here for the first time we show that AA-5-HT action at the spinal level involves CB2, with potential contributions from GRP18 and/or GPR55 receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/27326920

The cannabinoid WIN 55,212-2 prevents neuroendocrine differentiation of LNCaP prostate cancer cells.

“Neuroendocrine (NE) differentiation represents a common feature of prostate cancer and is associated with accelerated disease progression and poor clinical outcome. Nowadays, there is no treatment for this aggressive form of prostate cancer.

The aim of this study was to determine the influence of the cannabinoid WIN 55,212-2 (WIN, a non-selective cannabinoid CB1 and CB2 receptor agonist) on the NE differentiation of prostate cancer cells.

Taken together, we demonstrate that PI3K/Akt/AMPK might be an important axis modulating NE differentiation of prostate cancer that is blocked by the cannabinoid WIN, pointing to a therapeutic potential of cannabinoids against NE prostate cancer.”

http://www.ncbi.nlm.nih.gov/pubmed/27324222

Fatty acid amide hydrolase inhibition for the symptomatic relief of Parkinsońs disease.

“Elements of the endocannabinoid system are strongly expressed in the basal ganglia where they suffer profound rearrangements after dopamine depletion.

Modulation of the levels of the endocannabinoid 2-arachidonoyl glycerol by inhibiting monoacylglycerol lipase alters glial phenotypes and provides neuroprotection in a mouse model of Parkinsońs disease.

In this study, we assessed whether inhibiting fatty acid amide hydrolase could also provide beneficial effects on the time course of this disease.

Together, these results demonstrate an effect of fatty acid amide hydrolase inhibition on the motor symptoms of Parkinsońs disease in two distinct experimental models that is mediated by cannabinoid receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/27318096

Cannabinoid receptor agonism suppresses tremor, cognition disturbances and anxiety-like behaviors in a rat model of essential tremor.

“Cognitive and motor disturbances are serious consequences of tremor induced by motor disorders. Despite a lack of effective clinical treatment, some potential therapeutic agents have been used to alleviate the cognitive symptoms in the animal models of tremor.

In the current study, the effects of WIN55, 212-2 (WIN), a cannabinoid receptor (CBR) agonist, on harmaline-induced motor and cognitive impairments was studied.

The neuroprotective and anxiolytic effects of WIN demonstrated in the current study can be offered cannabinoid receptor (CBR) agonism as a potential neuroprotective agent in the treatment of patients with tremor that manifest mental dysfunctions.”

http://www.ncbi.nlm.nih.gov/pubmed/27317835

Upregulation of the cannabinoid CB2 receptor in environmental and viral inflammation-driven rat models of Parkinson’s disease.

“In recent years, it has become evident that Parkinson’s disease is associated with a self-sustaining cycle of neuroinflammation and neurodegeneration, with dying neurons activating microglia, which, once activated, can release several factors that kill further neurons.

One emerging pharmacological target that has the potential to break this cycle is the microglial CB2 receptor which, when activated, can suppress microglial activity and reduce their neurotoxicity.

However, very little is known about CB2 receptor expression in animal models of Parkinson’s disease which is essential for valid preclinical assessment of the anti-Parkinsonian efficacy of drugs targeting the CB2 receptor.

Therefore, the aim of this study was to investigate and compare the changes that occur in CB2 receptor expression in environmental and inflammation-driven models of Parkinson’s disease.

Thus, this study has shown that CB2 receptor expression is dysregulated in animal models of Parkinson’s disease, and has also revealed significant differences in the level of dysregulation between the models themselves.

This study indicates that these models may be useful for further investigation of the CB2 receptor as a target for anti-inflammatory disease modification in Parkinson’s disease.”

http://www.ncbi.nlm.nih.gov/pubmed/27317300

Cannabinoids reverse the effects of early stress on neurocognitive performance in adulthood.

“Early life stress (ES) significantly increases predisposition to psychopathologies. Cannabinoids may cause cognitive deficits and exacerbate the effects of ES.

Nevertheless, the endocannabinoid system has been suggested as a therapeutic target for the treatment of stress- and anxiety-related disorders.

Here we examined whether cannabinoids administered during “late adolescence” (extensive cannabis use in humans at the ages 18-25) could reverse the long-term adverse effects of ES on neurocognitive function in adulthood.

WIN administered during late adolescence prevented these stress-induced impairments and reduced anxiety levels.

There is a crucial role of the endocannabinoid system in the effects of early life stress on behavior at adulthood.”

http://www.ncbi.nlm.nih.gov/pubmed/27317195

Cannabinoids in the Brain: New Vistas on an Old Dilemma

“The use of cannabis as a therapeutic and recreational substance goes back to thousands of years throughout Asia, Middle East, Southern Africa, and South America.

The discovery of Δ-9-tetrahydrocannabinol (Δ9-THC) by Mechoulam and Gaoni in the midsixties as the major psychoactive constituent of cannabis sativa led to another important discovery, namely, its specific binding site that was isolated and cloned in 1990. This first cannabinoid receptor was coined CB1R and triggered a number of investigations on its expression, localization, and function within the body tissue including the brain, in various species. This was followed by the discovery in 1992 of the first endocannabinoid (eCB), anandamide, followed by another cannabinoid receptor CB2R and a second endocannabinoid called 2-arachidonoylglycerol (2-AG). Later on, some of the enzymes responsible for their synthesis (N-acyl phosphatidylethanolamine phospholipase D (NAPE-PLD); diacylglycerol lipase (DAGL)) and degradation (fatty acid amide hydrolase (FAAH); monoacylglycerol lipase (MAGL)) were identified.

Studies on the expression and localization of the cannabinoid receptors in the brain have burgeoned in the last decade and have furnished valuable data on their putative involvement in various sensory-motor and cognitive functions in diverse animal species, including Man. These studies have recently received substantial attention from pharmaceutical companies as a potential source for novel treatments. Additionally, the dilemma of legalizing the use of cannabis in some countries makes the investigation on cannabinoid systems more momentous. This special issue is therefore timely and brings historical and groundbreaking novel research on the role of these cannabinoid receptors in the mammalian central nervous system (CNS).

We hope that the collected papers in this special issue will contribute to the understanding of the various mechanisms involved in the functions of the endocannabinoid system and the development of new pharmaceutical tools to treat visual disorders.”

http://www.hindawi.com/journals/np/2016/9146713/

Inhibition of autophagy and enhancement of endoplasmic reticulum stress increase sensitivity of osteosarcoma Saos-2 cells to cannabinoid receptor agonist WIN55,212-2.

“WIN55,212-2, a cannabinoid receptor agonist, can activate cannabinoid receptors, which has proven anti-tumour effects in several tumour types. Studies showed that WIN can inhibit tumour cell proliferation and induce apoptosis in diverse cancers.

However, the role and mechanism of WIN in osteosarcoma are still unclear. In this study, we examined the effect of WIN55,212-2 on osteosarcoma cell line Saos-2 in terms of cell viability and apoptosis. Meanwhile, we further explored the role of endoplasmic reticulum stress and autophagy in apoptosis induced by WIN55,212-2.

Our results showed that the cell proliferation of Saos-2 was inhibited by WIN55,212-2 in a dose-dependent and time-dependent manner. WIN55,212-2-induced Saos-2 apoptosis through mitochondrial apoptosis pathway. Meanwhile, WIN55,212-2 can induce endoplasmic reticulum stress and autophagy in Saos-2 cells. Inhibition of autophagy and enhancement of endoplasmic reticulum stress increased apoptosis induced by WIN55,212-2 in Saos-2 cells.

These findings indicated that WIN55,212-2 in combination with autophagic inhibitor or endoplasmic reticulum stress activator may shed new light on osteosarcoma treatment.”

http://www.ncbi.nlm.nih.gov/pubmed/27309350