piperidines and 1-6-bis(cyclohexyloximinocarbonyl)hexane

Earlier reports suggest that the endocannabinoids may play a role of endogenous tumor growth modulators. In this study, we investigated whether inhibition of the enzymes involved in the synthesis and degradation of endocannabinoids may reduce colorectal cancer cell invasion and migration. The human colon adenocarcinoma Colo-205 cells were incubated with PF-3845, JZL-184 and RHC-80267 (fatty acid amide hydrolase (FAAH), mono- (MAGL) and diacylglycerol lipase (DAGL) inhibitors, respectively) for 48 h. The MTT colorimetric assay was performed to quantify cell viability. Next, Colo-205 cells were incubated with PF-3845 alone or with PF-3845 together with selected antagonists: AM 251, AM 630, SB 366791, RN 1734 and G-15 (CB

Topics: Adenocarcinoma; Amidohydrolases; Antineoplastic Agents; Benzodioxoles; Cell Line, Tumor; Cell Movement; Cell Survival; Colonic Neoplasms; Cyclohexanones; Enzyme Inhibitors; Humans; Piperidines; Pyridines; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2

Secretory diarrhoea is a leading cause of mortality and morbidity worldwide. Our aim was to characterize the effect of inhibition of selected enzymes involved in the synthesis or degradation of endocannabinoids on electrolyte equilibrium in the mouse colonic tissue. The aim of this study was to evaluate the effects of PF-3845, JZL-184 and RHC-80267, as inhibitors of fatty acid amide hydrolase (FAAH), monoacylglycerol (MAGL) and diacylglycerol lipase (DAGL), respectively on epithelial ion transport in isolated mouse colon stimulated by forskolin (FSK), veratridine (VER) and bethanechol (BET). Next, colonic tissue was co-incubated with selected inhibitors and cannabinoid receptor antagonists: AM 251 and AM 630 (CB

Topics: Amidohydrolases; Animals; Benzodioxoles; Cannabinoid Receptor Agonists; Cannabinoid Receptor Antagonists; Cyclohexanones; Diarrhea; Endocannabinoids; Enzyme Inhibitors; Indoles; Lipoprotein Lipase; Male; Mice; Monoglycerides; Piperidines; Pyrazoles; Pyridines; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2

It remains unclear how infantile febrile seizures (FS) enhance adult seizure susceptibility. Here we showed that the transient increase of interleukin-1β (IL-1β) after prolonged FS promoted adult seizure susceptibility, which was blocked by interleukin-1 receptor antagonist (IL-1Ra) within a critical time window. Postnatal administered IL-1β alone mimicked the effect of FS on adult seizure susceptibility. IL-1R1 knockout mice were not susceptible to adult seizure after prolonged FS or IL-1β treatment. Prolonged FS or early-life IL-1β treatment increased the expression of cannabinoid type 1 receptor (CB1R) for over 50 days, which was blocked by IL-1Ra or was absent in IL-1R1 knockout mice. CB1R antagonist, knockdown and endocannabinoid synthesis inhibitor abolished FS or IL-1β-enhanced seizure susceptibility. Thus, this work identifies a pathogenic role of postnatal IL-1β/IL-1R1 pathway and subsequent prolonged prominent increase of endocannabinoid signaling in adult seizure susceptibility following prolonged FS, and highlights IL-1R1 as a potential therapeutic target for preventing the development of epilepsy after infantile FS.

Topics: Aging; Animals; Benzoxazines; Cannabinoid Receptor Antagonists; Cyclohexanones; Gene Expression Regulation; Hippocampus; Humans; Interleukin 1 Receptor Antagonist Protein; Interleukin-1beta; Lipoprotein Lipase; Mice; Mice, Knockout; Morpholines; Naphthalenes; Piperidines; Pyrazoles; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB1; Rimonabant; RNA, Small Interfering; Seizures; Seizures, Febrile; Signal Transduction; Tissue Culture Techniques

Patients with temporal lobe epilepsy (TLE) often suffer from comorbid psychiatric diagnoses such as depression, anxiety, or impaired cognitive performance. Endocannabinoid (eCB) signaling is a key regulator of synaptic neurotransmission and has been implicated in the mechanisms of epilepsy as well as several mood disorders and cognitive impairments.. We employed a pilocarpine model of TLE in C57/BJ mice to investigate the role of eCB signaling in epileptogenesis and concomitant psychiatric comorbidities.. We sought to alter the neuronal levels of a known eCB receptor ligand, 2-arachidonylglycerol (2-AG), through the use of RHC80267 or JZL184. Pilocarpine-treated mice were treated with RHC80267 (1.3 μmol) or JZL184 (20 mg/kg) immediately after the termination of status epilepticus (SE), which was followed by daily treatment for the next 7 days. Our results indicated that RHC80267 treatment significantly reduced the percentage of mice suffering from spontaneous recurrent seizures (SRS) in addition to decreasing the duration of observed seizures when compared to vehicle treatment. Furthermore, RHC80267 attenuated depression and anxiety-related behaviors, improved previously impaired spatial learning and memory, and inhibited seizure-induced hippocampal neuronal loss during the chronic epileptic period. In contrast, JZL184 administration markedly increased the frequency and the duration of observed SRS, enhanced the previously impaired neuropsychological performance, and increased hippocampal damage following SE.. These findings suggest that RHC80267 treatment after the onset of SE could result in an amelioration of the effects found during the chronic epileptic period and yield an overall decrease in epileptic symptoms and comorbid conditions. Thus, alterations to endocannabinoid signaling may serve as a potential mechanism to prevent epileptogenesis and manipulation of this signaling pathway as a possible drug target.

Topics: Animals; Anticonvulsants; Benzodioxoles; Cyclohexanones; Disease Models, Animal; Electroencephalography; Epilepsy, Temporal Lobe; Exploratory Behavior; Hindlimb Suspension; Hippocampus; Male; Maze Learning; Mice; Mice, Inbred C57BL; Neurodegenerative Diseases; Piperidines

Acute stress reduces pain sensitivity by engaging an endocannabinoid signaling circuit in the midbrain. The neural mechanisms governing this process and molecular identity of the endocannabinoid substance(s) involved are unknown. We combined behavior, pharmacology, immunohistochemistry, RNA interference, quantitative RT-PCR, enzyme assays, and lipidomic analyses of endocannabinoid content to uncover the role of the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG) in controlling pain sensitivity in vivo. Here, we show that footshock stress produces antinociception in rats by activating type 5 metabotropic glutamate receptors (mGlu(5)) in the dorsolateral periaqueductal gray (dlPAG) and mobilizing 2-AG. Stimulation of mGlu(5) in the dlPAG with DHPG [(S)-3,5-dihydroxyphenylglycine] triggered 2-AG formation and enhanced stress-dependent antinociception through a mechanism dependent upon both postsynaptic diacylglycerol lipase (DGL) activity, which releases 2-AG, and presynaptic CB(1) cannabinoid receptors. Pharmacological blockade of DGL activity in the dlPAG with RHC80267 [1,6-bis(cyclohexyloximinocarbonylamino)hexane] and (-)-tetrahydrolipstatin (THL), which inhibit activity of DGL-α and DGL-β isoforms, suppressed stress-induced antinociception. Inhibition of DGL activity in the dlPAG with THL selectively decreased accumulation of 2-AG without altering levels of anandamide. The putative 2-AG-synthesizing enzyme DGL-α colocalized with mGlu(5) at postsynaptic sites of the dlPAG, whereas CB(1) was confined to presynaptic terminals, consistent with a role for 2-AG as a retrograde signaling messenger. Finally, virally mediated silencing of DGL-α, but not DGL-β, transcription in the dlPAG mimicked effects of DGL inhibition in suppressing both endocannabinoid-mediated stress antinociception and 2-AG formation. The results indicate that activation of the postsynaptic mGlu(5)-DGL-α cascade triggers retrograde 2-AG signaling in vivo. This pathway is required for endocannabinoid-mediated stress-induced analgesia.

Topics: Analgesia; Analysis of Variance; Animals; Arachidonic Acids; Cannabinoid Receptor Modulators; Cyclohexanones; Dose-Response Relationship, Drug; Electroconvulsive Therapy; Endocannabinoids; Excitatory Amino Acid Antagonists; Glycerides; Lipoprotein Lipase; Male; Methoxyhydroxyphenylglycol; Mice; Microscopy, Immunoelectron; Pain; Periaqueductal Gray; Piperidines; Protease Inhibitors; Pyrazoles; Pyridines; Rats; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB1; Receptor, Metabotropic Glutamate 5; Receptors, Metabotropic Glutamate; Rimonabant; RNA, Messenger; RNA, Small Interfering; Synapses; Tandem Mass Spectrometry

We previously reported that intracerebroventricularly (i.c.v.) administered (±)-epibatidine (a potent agonist of nicotinic acetylcholine receptors) (1, 5 and 10 nmol/animal) dose-dependently elevated plasma levels of noradrenaline and adrenaline and that this response was reduced by i.c.v. administered indomethacin (cyclooxygenase inhibitor) and abolished by bilateral adrenalectomy, indicating the involvement of brain arachidonic acid, as a substrate of cyclooxygenase, in this alkaloid-induced secretion of both catecholamines from the adrenal medulla in rats. Arachidonic acid is mainly released by the action of phospholipase A(2), but is also released by a phospholipase C-, diacylglycerol lipase- and monoacylglycerol lipase-mediated pathway. In the present study, (±)-epibatidine (5 nmol/animal, i.c.v.)-induced elevation of plasma catecholamines was not influenced by pretreatment with mepacrine (phospholipase A(2) inhibitor) (1.1 and 2.2 μmol/animal, i.c.v.), but was effectively reduced by pretreatment with U-73122 (1-[6-[[(17 β)-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione) (phospholipase C inhibitor) (10 and 30 nmol/animal, i.c.v.), RHC-80267 [1,6-bis(cyclohexyloximinocarbonylamino)hexane] (diacylglycerol lipase inhibitor) (1.3 and 2.6 μmol/animal, i.c.v.), MAFP (methyl arachidonoyl fluorophosphonate) (monoacylglycerol lipase inhibitor) (0.7 and 1.4 μmol/animal, i.c.v.) or JZL184 [4-nitrophenyl 4-(dibenzo[d][1,3]dioxol-5-yl(hydroxy)methyl)piperidine-1-carboxylate] (selective monoacylglycerol lipase inhibitor) (0.7 and 1.4 μmol/animal, i.c.v.). Immunohistochemical studies demonstrated that (±)-epibatidine (10 nmol/animal, i.c.v.) activates spinally projecting neurons expressing monoacylglycerol lipase in the rat hypothalamic paraventricular nucleus, a control center of central sympatho-adrenomedullary outflow. Taken together, the brain phospholipase C-, diacylglycerol lipase- and monoacylglycerol lipase-mediated pathway seems to be involved in the centrally administered (±)-epibatidine-induced activation of central adrenomedullary outflow in rats.

Topics: Adrenal Medulla; Animals; Arachidonic Acids; Benzodioxoles; Brain; Bridged Bicyclo Compounds, Heterocyclic; Catecholamines; Cyclohexanones; Esterases; Estrenes; Lipoprotein Lipase; Male; Monoacylglycerol Lipases; Neurons; Nicotinic Agonists; Organophosphonates; Paraventricular Hypothalamic Nucleus; Piperidines; Pyridines; Pyrrolidinones; Rats; Rats, Wistar; Type C Phospholipases

The reason why neurons synthesize more than one endocannabinoid (eCB) and how this is involved in the regulation of synaptic plasticity in a single neuron is not known. We found that 2-arachidonoylglycerol (2-AG) and anandamide mediate different forms of plasticity in the extended amygdala of rats. Dendritic L-type Ca(2+) channels and the subsequent release of 2-AG acting on presynaptic CB1 receptors triggered retrograde short-term depression. Long-term depression was mediated by postsynaptic mGluR5-dependent release of anandamide acting on postsynaptic TRPV1 receptors. In contrast, 2-AG/CB1R-mediated retrograde signaling mediated both forms of plasticity in the striatum. These data illustrate how the eCB system can function as a polymodal signal integrator to allow the diversification of synaptic plasticity in a single neuron.

Topics: Animals; Arachidonic Acids; Biophysics; Calcium; Calcium Channel Blockers; Calcium Channels, L-Type; Cannabinoid Receptor Modulators; Chromones; Cyclohexanones; Electric Stimulation; Endocannabinoids; Enzyme Inhibitors; Excitatory Amino Acid Antagonists; Glycerides; In Vitro Techniques; Long-Term Synaptic Depression; Neurons; Nimodipine; Patch-Clamp Techniques; Piperidines; Pyrazoles; Pyridines; Rats; Rats, Sprague-Dawley; Receptor, Cannabinoid, CB2; Receptor, Metabotropic Glutamate 5; Receptors, Metabotropic Glutamate; Septal Nuclei; Signal Transduction; Synapses; Time Factors; TRPV Cation Channels

Endocannabinoids (ECs) act as retrograde messengers that enable postsynaptic cells to regulate the strength of their synaptic inputs. Here, by using physiological and histological techniques, we showed that, unlike in other parts of the brain, excitatory inputs are more sensitive than inhibitory inputs to EC signaling in the dorsal cochlear nucleus (DCN), an auditory brainstem nucleus. The principal cells of the DCN, fusiform cells, integrate acoustic signals through nonplastic synapses located in the deep layer with multimodal sensory signals carried by plastic parallel fibers in the molecular layer. Parallel fibers contact fusiform cells and inhibitory interneurons, the cartwheel cells, which in turn inhibit fusiform cells. Postsynaptic depolarization or pairing of postsynaptic potentials (PSPs) with action potentials (APs) induced EC-mediated modulation of excitatory inputs but did not affect inhibitory inputs. Quantitative electron microscopical studies showed that glutamatergic terminals express more cannabinoid 1 receptors (CB1Rs) than glycinergic terminals. Fusiform and cartwheel cells express diacylglycerol lipase alpha and beta (DGLalpha/beta), the two enzymes involved in the generation of the EC, 2-arachidonoyl-glycerol (2-AG). DGLalpha and DGLbeta are found in the spines of cartwheel but not fusiform cells indicating that the synthesis of ECs is more distant from parallel fiber synapses in fusiform than cartwheel cells. The differential localization and density of DGLalpha/beta and CB1Rs leads to cell- and input-specific EC signaling that favors activity-dependent EC-mediated suppression at synapses between parallel fibers and cartwheel cell spines, thus leading to reduced feedforward inhibition in fusiform cells. We propose that EC signaling is a major modulator of the balance of excitation and inhibition in auditory circuits.

Topics: Animals; Animals, Newborn; Auditory Pathways; Benzoxazines; Biophysics; Calcium Channel Blockers; Cannabinoid Receptor Modulators; Cochlear Nucleus; Cyclohexanones; Dose-Response Relationship, Drug; Electric Stimulation; Endocannabinoids; In Vitro Techniques; Lipoprotein Lipase; Membrane Potentials; Mice; Mice, Inbred ICR; Microscopy, Immunoelectron; Morpholines; Naphthalenes; Neural Inhibition; Neurons; Patch-Clamp Techniques; Piperidines; Protease Inhibitors; Pyrazoles; Receptor, Cannabinoid, CB1; Synaptic Potentials; Time Factors

Previously, we reported that intracerebroventricularly (i.c.v.) administered arginine-vasopressin evokes the secretion of noradrenaline and adrenaline from adrenal medulla through the brain phospholipase C- and diacylglycerol-mediated and cyclooxygenase-mediated mechanisms in rats. Diacylglycerol can be hydrolyzed by diacylglycerol lipase to 2-arachidonoyl-sn-glycerol, which may be further degradated by monoacylglycerol lipase to free arachidonic acid, a representative substrate of cyclooxygenase. Recently, 2-arachidonoyl-sn-glycerol has been recognized as a major endocannabinoid, which can modulate synaptic transmission in the brain. In the present experiment, therefore, we examined (1) a role of the brain 2-arachidonoyl-sn-glycerol as a precursor of arachidonic acid in the centrally administered vasopressin-induced elevation of plasma noradrenaline and adrenaline, and (2) a regulatory role of the brain 2-arachidonoyl-sn-glycerol as an endocannabinoid on the vasopressin-induced response, using urethane-anesthetized rats. The vasopressin (0.2 nmol/animal, i.c.v.)-induced elevation of plasma catecholamines was reduced by RHC-80267 (diacylglycerol lipase inhibitor) (1.3 and 2.6 micromol/animal, i.c.v.) and also reduced by MAFP (monoacylglycerol lipase inhibitor) (0.7 and 1.4 micromol/animal, i.c.v.). MAFP (1.4 micromol/animal, i.c.v.) also attenuated the 2-arachidonoyl-sn-glycerol (0.5 micromol/animal, i.c.v.)-induced elevation of plasma catecholamines. AM 251 (cannabinoid CB(1) receptor antagonist) (90 and 180 nmol/animal, i.c.v.) potentiated the vasopressin (0.2 nmol/animal, i.c.v.)-induced response, while AM 630 (cannabinoid CB(2) receptor antagonist) (198 and 793 nmol/animal, i.c.v.) was largely ineffective. In addition, WIN 55212-2 (cannabinoid CB receptor agonist) (188 and 470 nmol/animal, i.c.v.) dose-dependently reduced the vasopressin-induced response. These results suggest that the brain 2-arachidonoyl-sn-glycerol generated from diacylglycerol plays a role as a precursor of arachidonic acid in the centrally administered vasopressin-induced activation of the adrenomedullary outflow, and also negatively regulates the peptide-induced central response through the brain cannabinoid CB(1) receptors in rats.

Topics: Adrenal Medulla; Animals; Arachidonic Acids; Arginine Vasopressin; Benzoxazines; Brain; Cannabinoid Receptor Agonists; Cannabinoid Receptor Antagonists; Cannabinoid Receptor Modulators; Catecholamines; Cyclohexanones; Dose-Response Relationship, Drug; Endocannabinoids; Enzyme Inhibitors; Epinephrine; Glycerides; Indoles; Injections, Intraventricular; Male; Morpholines; Naphthalenes; Norepinephrine; Organophosphonates; Piperidines; Pyrazoles; Rats; Rats, Wistar