Endocannabinoid system alterations in schizophrenia: association with cannabis use and antipsychotic medication.

Determining peripheral modulation of the endocannabinoid system (ECS) may be important for differentiating individuals with schizophrenia. Such differentiation can also be extended to subgroups of individuals, those who use cannabis and antipsychotic medications, particularly those who are treatment resistant. Patients and controls were recruited from the outpatient clinic of the Psychosis Group of the University of São Paulo, Brazil. A final sample of 93 individuals was divided into 3 groups: patients with schizophrenia using clozapine (treatment-resistant) (n = 29), patients with schizophrenia using another antipsychotic (n = 31), and controls (n = 33). By measuring the proteins and metabolites involved in the ECS pathways in the peripheral blood, AEA (anandamide), 2-AG (2-arachidonoyl ethanolamine), and CB2 receptor (peripheral) were quantified. Individuals reporting lifetime cannabis use had lower 2-AG plasma levels (p = 0.011). Regarding the CB2 receptor, the values of patients with schizophrenia and controls were similar, but those of patients using antipsychotics other than clozapine differed (p = 0.022). In generalized linear models to control for confounders, the use of cannabis remained the only factor that significantly influenced 2-AG levels. The relationship for non-clozapine antipsychotics as the only factor related to CB2 changes was marginally significant. We found for the first time that cannabis use and non-clozapine antipsychotic medication are potentially involved in the modulation of the ECS, specifically influencing 2-AG endocannabinoid and CB2 receptor levels. More studies regarding the ECS are needed since it has been increasingly related to the physiopathology of schizophrenia.

Sex- and age-specific respiratory alterations induced by prenatal exposure to the cannabinoid receptor agonist WIN 55,212-2 in rats.

BACKGROUND AND PURPOSE: Cannabis legalization has risen in many countries, and its use during pregnancy has increased. The endocannabinoid system is present in the CNS at early stages of embryonic development, and regulates functional brain maturation including areas responsible for respiratory control, data on the influence of external cannabinoids on the development of the respiratory system and possible consequences during postnatal life are limited. EXPERIMENTAL APPROACH: We evaluated the effects of prenatal exposure to synthetic cannabinoid (WIN 55,212-2 [WIN], 0.5 mg·kg-1 ·day-1 ) on the respiratory control system in neonatal (P0, P6-7 and P12-13) and juvenile (P27-28) male and female rats. KEY RESULTS: WIN administration to pregnant rats interfered sex-specifically with breathing regulation of offspring, promoting a greater sensitivity to CO2 at all ages in males (except P6-7) and in juvenile females. An altered hypoxic chemoreflex was observed in P0 (hyperventilation) and P6-7 (hypoventilation) males, which was absent in females. Along with breathing alterations, brainstem analysis showed an increase in the number of catecholaminergic neurons and cannabinoid receptor type 1 (CB1 ) and changes in tissue respiration in the early males. A reduction in pulmonary compliance was observed in juvenile male rats. Preexposure to WIN enhanced spontaneous apnoea and reduced the number of serotoninergic (5-HT) neurons in the raphe magnus nucleus of P0 females. CONCLUSIONS AND IMPLICATIONS: These data demonstrate that excess stimulation of the endocannabinoid system during gestation has prolonged and sex-specific consequences for the respiratory control system.

A PLS study on the psychotropic activity for a series of cannabinoid compounds.

INTRODUCTION: The use of the Cannabis sativa plant by man has been common for centuries due to its numerous therapeutic properties resulting from the compounds present in it, called cannabinoids. However, the use of these compounds as drugs is still limited due to the psychotropic effects caused by them. The proteins that act as receptors of cannabinoid compounds were identified and characterized, being called CB1 and CB2 receptors. There is a series of 50 cannabinoid compounds that was studied through quantum and chemometric methods in order to obtain a mathematical model that could relate the structure of these compounds to their psychotropic activity. That model proved to be effective by predicting the psychoactivity of the 50 compounds from the series and elucidating relevant characteristics that imply in psychoactivity. However, most of these 50 compounds do not have experimental data of biological activity with CB1 and CB2 receptors. OBJECTIVES: This study aims to generate QSAR models in order to predict the biological activity of the 50 cannabinoid compounds and then relate the predicted biological activity values to the already known psychoactivity. METHODS: Another series of cannabinoid compounds was selected to generate and validate QSAR models, aiming to predict the biological activity of the 50 cannabinoid compounds with both CB1 and CB2 receptors. RESULTS: The PLS-CB1 and PLS-CB2 QSAR models were generated and validated in this work, proving to be highly predictive, and the biological activities (pK ) of the 50 cannabinoid compounds were predicted by them. It is important to highlight compounds Ic14, Ic18, and Ic19 (psychotropic inactive) which presented higher predicted pK values than the main cannabinoid compounds (Δ9-THC and Δ8-THC). Also, compound Ic21 stood out as the highest value of the predicted biological activities in the interaction with the CB2 receptor. CONCLUSION: The generated PLS models and the predicted pKi values of the 50 cannabinoid compounds can provide valuable information in the drug design of new cannabinoid compounds that can interact with CB1 and CB2 receptors in a therapeutic way with no psychotropic effects.

Endocannabinoid system and periodontitis: mechanisms and therapeutic implications / Sistema endocanabinoide e periodontite: mecanismos e implicações terapêuticas

Introdução: A periodontite é um importante problema de saúde pública. Embora o princípio da terapia da periodontite esteja focado principalmente na remoção do biofilme dental e dos fatores associados, sua fisiopatologia registra diferentes eventos moleculares e inflamatórios relacionados ao sistema imunológico do hospedeiro, como a participação do sistema endocanabinoide. Objetivo: Esta revisão teve como objetivo explorar e elucidar os mecanismos e papéis do sistema endocanabinoide na fisiopatologia da periodontite e suas possibilidades para futuras terapias relacionadas. Material e método: Realizou-se uma busca eletrônica na plataforma PubMed por estudos envolvendo a ação do sistema endocanabinoide sobre a periodontite. Resultado: Dezenove estudos clínicos e pré-clínicos foram incluídos nesta revisão narrativa. Conclusão: Os receptores canabinoides tipo 1 e 2 são componentes integrais do sistema endocanabinoide e manifestam-se de várias formas nos tecidos periodontais. As ações e mecanismos através dos quais os receptores canabinoides são ativados em locais saudáveis ou inflamados continuam a ser o foco de investigações em curso. Além disso, os fitocanabinoides e canabinoides sintéticos apresentam potencial como tratamentos, com estudos pré-clínicos indicando benefícios na redução da inflamação e na facilitação da reparação dos tecidos.

Introduction: Periodontitis is a major public health problem. Although the principle of periodontitis therapy is mainly focused on removing dental biofilm and associated factors, its physiopathology enrolls different molecular and inflammatory events related to the host immune system, as the participation of the endocannabinoid system. Objective: This review aimed to explore and elucidate the mechanisms and roles of the endocannabinoid system on periodontitis physiopathology and its possibilities for future related therapies. Material and method: An electronic search was carried out on the PubMed platform for studies involving the action of the endocannabinoid system on periodontitis. Result: Nineteen clinical and preclinical studies were included in this narrative review. Conclusion: Cannabinoid receptors type 1 and 2 are integral components of the endocannabinoid system, manifesting in various forms in the periodontal tissues. The actions and mechanisms through which cannabinoid receptors are activated in healthy or inflamed sites remain the focus of ongoing investigations. Moreover, phytocannabinoids and synthetic cannabinoids show therapeutic potential, with pre-clinical studies indicating benefits in reducing inflammation and facilitating tissue repair

ZnO Nanoparticles Induce Dyslipidemia and Atherosclerotic Lesions Leading to Changes in Vascular Contractility and Cannabinoid Receptors Expression as Well as Increased Blood Pressure.

ZnO nanoparticles (ZnONPs) have been shown to have therapeutic potential in some diseases such as diabetes and cancer. However, concentration-dependent adverse effects have also been reported. Studies which evaluate the effects of ZnONPs on the cardiovascular system are scarce. This study aimed to evaluate the cardiovascular effects of a low dose of ZnONPs administered chronically in healthy rats. Changes in dyslipidemia biomarkers, blood pressure, aortic wall structure, vascular contractility, and expression of cannabinoid receptors in the aorta wall were evaluated. Healthy rats were divided into two groups: control or treated (one, two, and three months). The treated rats received an oral dose of 10 mg/kg/day. The results showed that treatment with ZnONPs induced dyslipidemia from the first month, increasing atherosclerosis risk, which was confirmed by presence of atherosclerotic alterations revealed by aorta histological analysis. In in vitro assays, ZnONPs modified the aorta contractile activity in response to the activation of cannabinoid receptors (CB1 and CB2). The expression of CB1 and CB2 was modified as well. Moreover, ZnONPs elicited an increase in blood pressure. In conclusion, long-time oral administration of ZnONPs induce dyslipidemia and atherosclerosis eliciting alterations in aorta contractility, CB1 and CB2 receptors expression, and an increase in blood pressure in healthy rats.

ß-Caryophyllene Reduces DNA Oxidation and the Overexpression of Glial Fibrillary Acidic Protein in the Prefrontal Cortex and Hippocampus of d-Galactose-Induced Aged BALB/c Mice.

Aging is associated with detrimental cellular and cognitive changes, making it an important public health concern; yet, many of these changes may be influenced by nutritional interventions. The natural sesquiterpene ß-caryophyllene (BCP) has anti-inflammatory and antioxidant effects that are mediated by cannabinoid type-2 receptor activation, and these actions promote neuroprotection in different animal models that involve a cognitive damage. Consequently, whether chronic administration of BCP might prevent the age-related cellular and cognitive damage in a model of aging induced by chronic d-galactose (GAL) consumption was assessed here. Male BALB/c mice were administered BCP (10 mg/kg, oral), GAL (300 mg/kg, intraperitoneal), or GAL+BCP, and long-term memory and cognitive flexibility were evaluated in the normal and the reverse phases of Morris water maze test. In addition, immunohistochemistry was performed on prefrontal and hippocampal brain slices to detect glial acidic fibrillary protein and DNA oxidation. Although GAL administration reduced cognitive flexibility (P = .0308), this functional damage was not reversed by administering BCP. However, GAL administration also elevated the total number of astrocytes and their interactions in the hippocampus, and increasing DNA oxidation in the prefrontal cortex. BCP administration impeded the rise in the total number of astrocytes (P = .0286) and the DNA oxidation (P = .0286) in mice that received GAL. Hence, although BCP did not improve cognitive flexibility, it did produce a neuroprotective effect at the molecular and cellular level in the GAL model of aging.

Electroacupuncture increases immunoexpression of CB1 and CB2 receptors in experimental model of inflammatory bone loss.

This study evaluated the participation of CB1 and CB2 receptors in the antiresorptive effect of electroacupuncture (EA) on an experimental model of inflammatory bone loss in rats. 30 rats were divided into five groups: C (control); EP (experimental periodontitis); EA (C+ EA); EP-EA (EP+ EA in the acupoints LI4, LG11, ST36, ST44); EP - EA-sham (EP+ EA in sham acupoints). For the EP groups, a ligature was placed around the right mandibular first molars at day 1. Sessions of EA or EA-sham were assigned every other day. Animals were euthanized at day 11. Histometric analysis was performed to evaluate the percentage of bone area in the furcation area. Immunolabeling patterns in the periodontal tissues and immunofluorescent staining in the trigeminal ganglia and in the trigeminal spinal tract for CB1 and CB2 receptors were performed. It was observed increased bone loss in the furcation in the EP and EP-EA-sham groups, in comparison to the other groups (p < 0.05). Enhanced CB2 immunolabeling was observed in the periodontal tissues in the EP-EA group, when compared to the EP and EP-EA-sham groups (p < 0.05). Increased CB1 immunofluorescent staining was observed in the neural tissues in the EA treated group in comparison with the other groups (p < 0.05), while no expression of CB2 was observed in those regions. Our study showed that in the presence of inflammatory bone disease, EA treatment reduced bone erosion and increased the immunoexpression of CB1 in the neural tissues and CB2 in the periodontal tissues.

(-)-ß-Caryophyllene, a CB2 Receptor-Selective Phytocannabinoid, Suppresses Motor Paralysis and Neuroinflammation in a Murine Model of Multiple Sclerosis.

(-)-ß-caryophyllene (BCP), a cannabinoid receptor type 2 (CB2)-selective phytocannabinoid, has already been shown in precedent literature to exhibit both anti-inflammatory and analgesic effects in mouse models of inflammatory and neuropathic pain. Herein, we endeavored to investigate the therapeutic potential of BCP on experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS). Furthermore, we sought to demonstrate some of the mechanisms that underlie the modulation BCP exerts on autoimmune activated T cells, the pro-inflammatory scenery of the central nervous system (CNS), and demyelination. Our findings demonstrate that BCP significantly ameliorates both the clinical and pathological parameters of EAE. In addition, data hereby presented indicates that mechanisms underlying BCP immunomodulatory effect seems to be linked to its ability to inhibit microglial cells, CD4+ and CD8+ T lymphocytes, as well as protein expression of pro-inflammatory cytokines. Furthermore, it diminished axonal demyelination and modulated Th1/Treg immune balance through the activation of CB2 receptor. Altogether, our study represents significant implications for clinical research and strongly supports the effectiveness of BCP as a novel molecule to target in the development of effective therapeutic agents for MS.

A spider derived peptide, PnPP-19, induces central antinociception mediated by opioid and cannabinoid systems.

BACKGROUND: Some peptides purified from the venom of the spider Phoneutria nigriventer have been identified as potential sources of drugs for pain treatment. In this study, we characterized the antinociceptive effect of the peptide PnPP-19 on the central nervous system and investigated the possible involvement of opioid and cannabinoid systems in its action mechanism. METHODS: Nociceptive threshold to thermal stimulation was measured according to the tail-flick test in Swiss mice. All drugs were administered by the intracerebroventricular route. RESULTS: PnPP-19 induced central antinociception in mice in the doses of 0.5 and 1 µg. The non-selective opioid receptor antagonist naloxone (2.5 and 5 µg), µ-opioid receptor antagonist clocinnamox (2 and 4 µg), δ-opioid receptor antagonist naltrindole (6 and 12 µg) and CB1 receptor antagonist AM251 (2 and 4 µg) partially inhibited the antinociceptive effect of PnPP-19 (1 µg). Additionally, the anandamide amidase inhibitor MAFP (0.2 µg), the anandamide uptake inhibitor VDM11 (4 µg) and the aminopeptidase inhibitor bestatin (20 µg) significantly enhanced the antinociception induced by a low dose of PnPP-19 (0.5 µg). In contrast, the κ-opioid receptor antagonist nor-binaltorphimine (10 µg and 20 µg) and the CB2 receptor antagonist AM630 (2 and 4 µg) do not appear to be involved in this effect. CONCLUSIONS: PnPP-19-induced central antinociception involves the activation of CB1 cannabinoid, µ- and δ-opioid receptors. Mobilization of endogenous opioids and cannabinoids might be required for the activation of those receptors, since inhibitors of endogenous substances potentiate the effect of PnPP-19. Our results contribute to elucidating the action of the peptide PnPP-19 in the antinociceptive pathway.

The cannabinoid 2 receptor agonist ß-caryophyllene modulates the inflammatory reaction induced by Mycobacterium bovis BCG by inhibiting neutrophil migration.

OBJECTIVE AND DESIGN: ß-Caryophyllene (BCP) is a sesquiterpene that binds to the cannabinoid 2 (CB2) receptor and exerts anti-inflammatory effects. In this study, we investigated the anti-inflammatory effect of BCP and another CB2 agonist, GP1a in inflammatory experimental model induced by Mycobacterium bovis (BCG). METHODS: C57Bl/6 mice were pretreated orally with BCP (0.5-50 mg/kg) or intraperitonealy with GP1a (10 mg/kg) 1 h before the induction of pleurisy or pulmonary inflammation by BCG. The direct action of CB2 agonists on neutrophils function was evaluated in vitro. RESULTS: ß-Caryophyllene (50 mg/kg) impaired BCG-induced neutrophil accumulation in pleurisy without affecting mononuclear cells or the production of TNF-α and CCL2/MCP-1. However, BCP inhibited CXCL1/KC, leukotriene B4 (LTB4), IL-12, and nitric oxide production. GP1a had a similar effect to BCP. Preincubation of neutrophils with BCP (10 µM) impaired chemotaxis toward LTB4 and adhesion to endothelial cells stimulated with TNF-α, and both, BCP and GP1a, impaired LTB4-induced actin polymerization. CONCLUSION: These results suggest that the CB2 receptor may represent a new target for modulating the inflammatory reaction induced by mycobacteria.

A spider derived peptide, PnPP-19, induces central antinociception mediated by opioid and cannabinoid systems

Some peptides purified from the venom of the spider Phoneutria nigriventer have been identified as potential sources of drugs for pain treatment. In this study, we characterized the antinociceptive effect of the peptide PnPP-19 on the central nervous system and investigated the possible involvement of opioid and cannabinoid systems in its action mechanism. Methods Nociceptive threshold to thermal stimulation was measured according to the tail-flick test in Swiss mice. All drugs were administered by the intracerebroventricular route. Results PnPP-19 induced central antinociception in mice in the doses of 0.5 and 1 g. The non-selective opioid receptor antagonist naloxone (2.5 and 5 g), -opioid receptor antagonist clocinnamox (2 and 4 g), -opioid receptor antagonist naltrindole (6 and 12 g) and CB1 receptor antagonist AM251 (2 and 4 g) partially inhibited the antinociceptive effect of PnPP-19 (1 g). Additionally, the anandamide amidase inhibitor MAFP (0.2 g), the anandamide uptake inhibitor VDM11 (4 g) and the aminopeptidase inhibitor bestatin (20 g) significantly enhanced the antinociception induced by a low dose of PnPP-19 (0.5 g). In contrast, the -opioid receptor antagonist nor-binaltorphimine (10 g and 20 g) and the CB2 receptor antagonist AM630 (2 and 4 g) do not appear to be involved in this effect. Conclusions PnPP-19-induced central antinociception involves the activation of CB1 cannabinoid, - and -opioid receptors. Mobilization of endogenous opioids and cannabinoids might be required for the activation of those receptors, since inhibitors of endogenous substances potentiate the effect of PnPP-19. Our results contribute to elucidating the action of the peptide PnPP-19 in the antinociceptive pathway.

A spider derived peptide, PnPP-19, induces central antinociception mediated by opioid and cannabinoid systems

Background: Some peptides purified from the venom of the spider Phoneutria nigriventer have been identified as potential sources of drugs for pain treatment. In this study, we characterized the antinociceptive effect of the peptide PnPP-19 on the central nervous system and investigated the possible involvement of opioid and cannabinoid systems in its action mechanism. Methods: Nociceptive threshold to thermal stimulation was measured according to the tail-flick test in Swiss mice. All drugs were administered by the intracerebroventricular route.Results: PnPP-19 induced central antinociception in mice in the doses of 0.5 and 1 µg. The non-selective opioid receptor antagonist naloxone (2.5 and 5 µg), µ-opioid receptor antagonist clocinnamox (2 and 4 µg), δ-opioid receptor antagonist naltrindole (6 and 12 µg) and CB1 receptor antagonist AM251 (2 and 4 µg) partially inhibited the antinociceptive effect of PnPP-19 (1 µg). Additionally, the anandamide amidase inhibitor MAFP (0.2 µg), the anandamide uptake inhibitor VDM11 (4 µg) and the aminopeptidase inhibitor bestatin (20 µg) significantly enhanced the antinociception induced by a low dose of PnPP-19 (0.5 µg). In contrast, the κ-opioid receptor antagonist nor-binaltorphimine (10 µg and 20 µg) and the CB2 receptor antagonist AM630 (2 and 4 µg) do not appear to be involved in this effect. Conclusions: PnPP-19-induced central antinociception involves the activation of CB1 cannabinoid, µ- and δ-opioid receptors. Mobilization of endogenous opioids and cannabinoids might be required for the activation of those receptors, since inhibitors of endogenous substances potentiate the effect of PnPP-19. Our results contribute to elucidating the action of the peptide PnPP-19 in the antinociceptive pathway.(AU)

A spider derived peptide, PnPP-19, induces central antinociception mediated by opioid and cannabinoid systems

Some peptides purified from the venom of the spider Phoneutria nigriventer have been identified as potential sources of drugs for pain treatment. In this study, we characterized the antinociceptive effect of the peptide PnPP-19 on the central nervous system and investigated the possible involvement of opioid and cannabinoid systems in its action mechanism. Methods Nociceptive threshold to thermal stimulation was measured according to the tail-flick test in Swiss mice. All drugs were administered by the intracerebroventricular route. Results PnPP-19 induced central antinociception in mice in the doses of 0.5 and 1 g. The non-selective opioid receptor antagonist naloxone (2.5 and 5 g), -opioid receptor antagonist clocinnamox (2 and 4 g), -opioid receptor antagonist naltrindole (6 and 12 g) and CB1 receptor antagonist AM251 (2 and 4 g) partially inhibited the antinociceptive effect of PnPP-19 (1 g). Additionally, the anandamide amidase inhibitor MAFP (0.2 g), the anandamide uptake inhibitor VDM11 (4 g) and the aminopeptidase inhibitor bestatin (20 g) significantly enhanced the antinociception induced by a low dose of PnPP-19 (0.5 g). In contrast, the -opioid receptor antagonist nor-binaltorphimine (10 g and 20 g) and the CB2 receptor antagonist AM630 (2 and 4 g) do not appear to be involved in this effect. Conclusions PnPP-19-induced central antinociception involves the activation of CB1 cannabinoid, - and -opioid receptors. Mobilization of endogenous opioids and cannabinoids might be required for the activation of those receptors, since inhibitors of endogenous substances potentiate the effect of PnPP-19. Our results contribute to elucidating the action of the peptide PnPP-19 in the antinociceptive pathway.(AU)