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Objectives: In view of the neuroprotective characteristic of cannabidiol (CBD) and its beneficial action on aversive memory in non-diabetic animals, we aimed to investigate in animals with experimentally induced type-1 diabetes mellitus (T1DM) whether CBD treatment would be able to impair the contextual fear memory consolidation, its generalisation and whether the effect would be lasting. We also investigated the CBD effect on anxiety-like responses. Methods: After T1DM induction, animals received single or more prolonged treatment with CBD and were submitted to the contextual fear conditioning test. As expression of activity-regulated cytoskeletal-associated (Arc) protein is necessary for memory consolidation, we evaluated its expression in the dorsal hippocampus (DH). For evaluating anxiety-related responses, animals were submitted to the elevated plus maze test (EPMT), in which the time and number of entries in the open arms were used as anxiety index. Results: A single injection of CBD impaired the contextual fear memory consolidation and its generalisation, which was evaluated by exposing the animal in a neutral context. This single injection was able to reduce the elevated expression of Arc in the DH from these animals. Interestingly, more prolonged treatment with CBD also impaired the persistence of context-conditioned fear memory and induced an anxiolytic-like effect, as the treated group spent more time in the open arms of the EPMT. Conclusion: CBD interferes with contextual fear memory and the dosage regimen of treatment seems to be important. Moreover, we cannot rule out the involvement of emotional aspects in these processes related to fear memory.

Oxaliplatin-induced neurotoxicity is expressed as a dose-limiting peripheral sensory neuropathy (PSN). Cannabinoid substances have been investigated for the analgesic effect. This study aimed to investigate the role of cannabinoid receptors in oxaliplatin-associated PSN. Swiss male mice received nine oxaliplatin injections (2 mg/kg, i.v.). Mechanical and thermal nociceptive tests were performed for 56 days. CB1, CB2, and c-Fos expression were assessed in dorsal root ganglia (DRG), spinal cord (SC), trigeminal ganglia (TG), spinal trigeminal nucleus caudalis (Sp5C), and periaqueductal gray (PAG). Iba-1 expression was assessed in DRG and ATF3 in TG. Cannabidiol (10 mg/kg, p.o.) or a CB1/CB2 non-selective agonist (WIN 55,212–2; 0.5 mg/kg, s.c.) or AM251 (CB1 antagonist) or AM630 (CB2 antagonist) (3 mg/kg, i.p.) were injected before oxaliplatin. Oxaliplatin increased CB1 in DRG, SC, TG, Sp5C, and ventrolateral PAG, with no interference in CB2 expression. Cannabidiol increased CB1 in DRG, reduced mechanical hyperalgesia and c-Fos expression in DRG and SC. Additionally, WIN 55,212–2 increased CB1 in DRG, reduced mechanical hyperalgesia, cold allodynia and c-Fos expression in DRG and SC. CB1 blockage hastened the cold allodynia response, but the CB2 antagonist failed to modulate the oxaliplatin-induced nociceptive behavior. Oxaliplatin also increased Iba-1 in DRG, suggesting immune response modulation which was reduced by cannabidiol and enhanced by AM630. The modulation of the endocannabinoid system, through the CB1 receptor, attenuates the oxaliplatin-associated PNS. The activation of the endocannabinoid system could be considered as a therapeutic target for controlling oxaliplatin-associated neuropathy.

Background Brain magnetic resonance imaging studies have not investigated the cortical surface comprehensively in schizophrenia subjects by assessing thickness, surface area and gyrification separately during the first-episode of psychosis (FEP) or chronic schizophrenia (ChSch). Methods We investigated cortical surface abnormalities in 137 FEP patients and 240 ChSch subjects compared to 297 Healthy Controls (HC) contributed by five cohorts. Maps showing results of vertexwise between-group comparisons of cortical thickness, area, and gyrification were produced using T1-weighted datasets processed using FreeSurfer 5.3, followed by validated quality control protocols. Results FEP subjects showed large clusters of increased area and gyrification relative to HC in prefrontal and insuli cortices (Cohen's d: 0.049 to 0.28). These between-group differences occurred partially beyond the effect of sample. ChSch subjects displayed reduced cortical thickness relative to HC in smaller fronto-temporal foci (d: −0.73 to −0.35), but not beyond the effect of sample. Differences between FEP and HC subjects were associated with male gender, younger age, and earlier illness onset, while differences between ChSch and HC were associated with treatment-resistance and first-generation antipsychotic (FGA) intake independently of sample effect. Conclusions Separate assessments of FEP and ChSch revealed abnormalities that differed in regional distribution, phenotypes affected and effect size. In FEP, associations of greater cortical area and gyrification abnormalities with earlier age of onset suggest an origin on anomalous neurodevelopment, while thickness reductions in ChSch are at least partially explained by treatment-resistance and FGA intake. Associations of between-group differences with clinical variables retained statistical significance beyond the effect of sample.

Neuropathic pain (NP) is a complex health problem that includes sensorial manifestations such as evoked and ongoing pain. Cannabidiol (CBD) has shown potential in the treatment of NP and the combination between opioids and cannabinoids has provided promising results on pain relief. Thus, our study aimed to investigate the effect of treatment combination between CBD and morphine on evoked and ongoing pain, and the effect of CBD on morphine-induced tolerance in the model of chronic constriction injury (CCI) of the sciatic nerve in rats. Mechanical thresholds (i.e., evoked pain) were evaluated before and 7 days after surgery. We also employed a 4-day conditioned place preference (CPP) protocol, to evaluate relief of ongoing pain (6-9 days after surgery). Treatment with morphine (2 and 4 mg/kg) or CBD (30 mg/kg) induced a significant antinociceptive effect on evoked pain. The combination of CBD (30 mg/kg) and morphine (1 mg/kg) produced an enhanced antinociceptive effect, when compared to morphine alone (1 mg/Kg). Treatment with morphine (1 and 2 mg/kg) or CBD (30 mg/kg) alone failed to induce significant scores in the CPP test. However, combined treatment of CBD (30 mg/kg) and morphine (1 mg/kg) provided significant positive scores, increased the number of entrances in the drug-paired chamber in the CPP test and did not alter locomotor activity in rats. Lastly, treatment with CBD partially attenuated morphine-induced tolerance. In summary, our results support the indication of CBD as an adjuvant to opioid therapy for the attenuation of NP and opioid-induced analgesic tolerance.

This manuscript describes the development of magnetic restricted-access carbon nanotubes (M-RACNTs) for use as SPME sorbent to determine cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC) in human plasma samples by UHPLC-MS/MS. The adsorptive phase was immobilized on an SPME device by electromagnetic interactions between the M-RACNTs and a cylindrical neodymium magnet (3-mm diameter x 8-mm height) attached to a stainless-steel rod (3-mm diameter x 40-mm height). The M-RACNTs were synthesized by incorporating Fe

Background REM sleep behaviour disorder (RBD) is a common non-motor feature of Parkinson's disease (PD). Cannabidiol (CBD) is one of the main non-psychoactive components of Cannabis sativa and may represent an alternative route for treating RBD. Objective This study assessed the efficacy and safety of CBD for RBD in PD. Methods We conducted a phase II/III, double-blind, placebo-controlled clinical trial in 33 patients with RBD and PD. Patients were randomized 1:1 to CBD in doses of 75 to 300mg or matched capsules placebo and were followed up for 14 weeks. The primary outcomes were the frequency of nights with RBD, CGI-I, and CGI-S. Results CBD showed no difference to placebo for primary outcomes. Regarding secondary outcomes, we observed a significant improvement in average sleep satisfaction from the 4th to 8th week in the CBD versus placebo group with P = 0.049 and P = 0.038, respectively. Conclusion CBD, as an adjunct therapy, showed no reduction in RBD manifestations in PD patients. A transient improvement in sleep satisfaction with a dose of 300mg has been noted. © 2021 International Parkinson and Movement Disorder Society.

Huntington’s disease (HD) is an inherited neurodegenerative disease characterized by motor, cognitive and behavioral deficits. Some evidence suggests that the endocannabinoid system participates in the pathophysiology of HD. We conducted a cross-sectional study comparing plasma levels of anandamide and 2-arachidonoylglycerol in manifest HD gene-expansion carriers (HDGEC) and healthy controls, finding no difference in endocannabinoid levels between the groups. Correlations between endocannabinoid levels and clinical scales (Mini-Mental State Examination, Hospital Anxiety and Depression Scale, Unified Huntington Disease Rating Scale) were non-significant. We found a significant association between body mass index and anandamide levels in healthy controls but not in HDGEC.

PURPOSE OF REVIEW The two past decades have seen the production of a vast amount of evidence about the genetic and nongenetic factors that contribute to the onset of psychosis from various fields of research. The present article reviews recent evidence from four of these fields that were shown to be strongly associated with psychosis: proneness, urbanicity, trauma, and cannabis use. RECENT FINDINGS The evidence reviewed shows that all four sets of factors investigated here are implicated in the occurrence of psychosis. The specificity and complexity of these associations, however, are not yet clear and recent findings show that the directions of the associations described may be different than we first thought. SUMMARY It is clear that psychosis is strongly affected by a number of environmental determinants that act in concert with genetic determinants to cause psychotic disorders; however, these influences are complex and their actual impact may be difficult to establish because of poor definitions and specificity. Urbanicity in special is a poorly defined concept that seems to encompass different sets of factors in each study, which hinders discussions and conclusions regarding its impact.

Introduction: Recent studies have suggested that cannabidiol (CBD) could interconvert into Delta-8- and Delta-9- tetrahydrocannabinol. Materials and Methods: Thus, we tested the plasma samples of 120 healthy human subjects (60 male and 60 female), 60 in fasting and the other 60 under normal feeding conditions after acute administration of an oral solution containing CBD 300 mg. To do this, we developed a bioanalytical method to determine CBD and the presence of THC in plasma samples by Ultra-High Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry. Results: The results showed that THC was not detected in plasma after the administration of CBD, and those study participants did not present psychotomimetic effects. Conclusions: The findings presented here are consistent with previous evidence suggesting that the oral administration of CBD in a corn oil formulation is a safe route for the administration of the active substance without bioconversion to THC in humans.

The behavioural effects elicited by chemical constituents of Cannabis sativa, such as cannabidiol (CBD), on the ventromedial hypothalamus (VMH) are not well understood. There is evidence that VMH neurons play a relevant role in the modulation of unconditioned fear-related defensive behavioural reactions displayed by laboratory animals. This study was designed to explore the specific pattern of distribution of the CB1 receptors in the VMH and to investigate the role played by this cannabinoid receptor in the effect of CBD on the control of defensive behaviours and unconditioned fear-induced antinociception. A panic attack-like state was triggered in Wistar rats by intra-VMH microinjections of N-methyl-d-aspartate (NMDA). One of three different doses of CBD was microinjected into the VMH prior to local administration of NMDA. In addition, the most effective dose of CBD was used after pre-treatment with the CB1 receptor selective antagonist AM251, followed by NMDA microinjections in the VMH. The morphological procedures demonstrated distribution of labelled CB1 receptors on neuronal perikarya situated in dorsomedial, central and ventrolateral divisions of the VMH. The neuropharmacological approaches showed that both panic attack-like behaviours and unconditioned fear-induced antinociception decreased after intra-hypothalamic microinjections of CBD at the highest dose (100 nmol). These effects, however, were blocked by the administration of the CB1 receptor antagonist AM251 (100 pmol) in the VMH. These findings suggest that CBD causes panicolytic-like effects and reduces unconditioned fear-induced antinociception when administered in the VMH, and these effects are mediated by the CB1 receptor-endocannabinoid signalling mechanism in VMH.

Importance: Owing to its anti-inflammatory properties and antiviral “in vitro” effect against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), cannabidiol (CBD) has been proposed as a ...

Clinical and preclinical evidence has indicated that estrogen depletion leads to memory impairments and increases the susceptibility to neural damage. Here, we have sought to investigate the effects of Cannabidiol (CBD) a non-psychotomimetic compound from Cannabis sativa, on memory deficits induced by estrogen depletion in rats, and its underlying mechanisms. Adult rats were subjected to bilateral ovariectomy, an established estrogen depletion model in rodents, or sham surgery and allowed to recover for three weeks. After that, they received daily injections of CBD (10 mg/kg) for fourteen days. Rats were tested in the inhibitory avoidance task, a type of emotionally-motivated memory. After behavioral testing they were euthanized, and their hippocampi were isolated for analysis of components of the Akt/GSK3β survival pathway and the antiapoptotic protein Bcl2. Results revealed that ovariectomy impaired avoidance memory, and CBD was able to completely reverse estrogen depletion-induced memory impairment. Ovariectomy also reduced Akt/GSK3β pathway’s activation by decreasing the phosphorylation levels of Akt and GSK3β and Bcl2 levels, which were ameliorated by CBD. The present results indicate that CBD leads to a functional recovery accompanied by the Akt/GSK3β survival pathway’s activation, supporting its potential as a treatment for estrogen decline-induced deterioration of neural functioning and maintenance.

Cannabidiol (CBD), a major non-psychotomimetic component of the Cannabis sativa plant, shows therapeutic potential in several psychiatric disorders, including schizophrenia. The molecular mechanisms underlying the antipsychotic-like effects of CBD are not fully understood. Schizophrenia and antipsychotic treatment can modulate DNA methylation in the blood and brain, resulting in altered expression of diverse genes associated with this complex disorder. However, to date, the possible involvement of DNA methylation in the antipsychotic-like effects of CBD has not been investigated. Therefore, this study aimed at evaluating in mice submitted to the prepulse inhibition (PPI) model: i) the effects of a single injection of CBD or clozapine followed by AMPH or MK-801 on PPI and global DNA methylation changes in the ventral striatum and prefrontal cortex (PFC); and ii). if the acute antipsychotic-like effects of CBD would last for 24-h. AMPH (5 mg/kg) and MK-801 (0.5 mg/kg) impaired PPI. CBD (30 and 60 mg/kg), similar to clozapine (5 mg/kg), attenuated AMPH- and MK801-induced PPI disruption. AMPH, but not MK-801, increased global DNA methylation in the ventral striatum, an effect prevented by CBD. CBD and clozapine increased, by themselves, DNA methylation in the prefrontal cortex. The acute effects of CBD (30 or 60 mg/kg) on the PPI impairment induced by AMPH or MK-801 was also detectable 24 h later. Altogether, the results show that CBD induces acute antipsychotic-like effects that last for 24-h. It also modulates DNA methylation in the ventral striatum, suggesting a new potential mechanism for its antipsychotic-like effects.

The interest in psychedelic substances as potential treatments for psychiatric disorders is increasing. The β-carboline harmine, an Ayahuasca component, presents hallucinogenic and antidepressant effects. Although Ayuahuasca-and consequently harmine-is usually consumed in rituals, the role of social contexts in the behavioral effects of harmine has not been investigated yet. In this sense, affective states may modulate cohabitants' behavior, including learning/memory. This work investigates the effects of harmine on the learning/memory performance of rats evaluated on the contextual and tone fear conditioning (CFC and TFC) and on the plus-maze discriminative avoidance (PMDAT) tasks. The possible influence of a harmine-treated cohabitant was assessed by evaluating rats housed in homogeneous cages-where all the animals were acutely administered with the same treatment (vehicle, 5, 10, or 15 mg/kg harmine), and in heterogeneous cages-where each animal received a different drug treatment. The main results are: (a) harmine impaired CFC (10 mg/kg) and PMDAT discrimination (all doses); and (b) harmine caused a memory deficit in CFC, TFC, and PMDAT of untreated rats kept in heterogeneous cages. Our results show that harmine induces a memory deficit in tasks with emotional contexts. Further, the cohabitation with animals treated with this drug also seems to impair memory performance of untreated animals. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Made available in DSpace on 2019-10-03T17:32:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2019. Added 1 bitstream(s) on 2019-10-04T16:21:08Z : No. of bitstreams: 1 S2237-60892019005004105.pdf: 138281 bytes, checksum: 82ee0a3bfc7eb2097d959f9248faf11a (MD5) ResumoObjetivoApresentar o processo de adaptação transcultural do Personality Inventory for DSM-5 (PID-5) para o contexto brasileiro.MétodoA adaptação transcultural envolveu as etapas de tradução independente, versão síntese e retrotradução. A validade de conteúdo foi realizada por um comitê multidisciplinar de especialistas, com avaliação quantitativa dos índices de concordância. Por fim, o pré-teste foi conduzido com a população-alvo.ResultadoTodos os estágios da adaptação transcultural foram seguidos, e na maioria das estruturas avaliadas, os valores de concordância foram satisfatórios (≥ 4.75). Grande parte das sugestões de modificações feitas pelos especialistas foram acatadas, sendo as principais relacionadas a ajustes no tempo e concordância verbal e a inclusão de letras e palavras para permitir a flexão de gênero. No pré-teste nenhuma sugestão foi apresentada e o instrumento foi considerado compreensível.ConclusãoA versão brasileira do PID-5 mostrou-se adequada ao contexto brasileiro sob as perspectivas semântica, idiomática, cultural e conceitual. A versão brasileira avaliada é de uso livre, foi aprovada pelas editoras responsáveis pelos direitos autorais do instrumento e é considerada oficial. Novos estudos estão sendo conduzidos para aprimorar a busca por evidencias de validade e confiabilidade. AbstractObjectiveTo describe the process of cross-cultural adaptation of the Personality Inventory for DSM-5 (PID-5) to the Brazilian context.MethodCross-cultural adaptation involved the steps of independent translation of the instrument, synthesis version, and back-translation. Analysis of content validity was conducted by a multidisciplinary expert committee and consisted of quantitative assessment of agreement indicators. The test was then applied to a target population.ResultAll the steps required for a cross-cultural adaptation were followed and satisfactory agreement values (≥ 4.75) were reached for most of the structures assessed. Most of the changes suggested by the experts were followed; these changes consisted primarily of adjustments to verb tense and agreement and the inclusion of letters and words to allow gender inflection. In the pre-test, no suggestions were made and the instrument was considered comprehensible.ConclusionThe Brazilian version of the PID-5 was found to be adequate to the Brazilian context from semantic, idiomatic, cultural, and conceptual perspectives. The Brazilian version assessed here can be freely used, was approved by the publishers who hold the copyright on the instrument, and is considered the official version of the instrument. New studies are underway to determine the validity and reliability of the PID-5. Universidade de São Paulo Faculdade de Medicina de Ribeirão Preto Departamento de Neurociências e Ciências do Comportamento Instituto Nacional de Ciência e Tecnologia Universidade Estadual Paulista Faculdade de Medicina de Botucatu Departamento de Neurologia, Psicologia e Psiquiatria Faculdade Pio Décimo Universidade Federal de São Carlos Centro de Ciências Biológicas e da Saúde Universidade Estadual Paulista Faculdade de Medicina de Botucatu Departamento de Neurologia, Psicologia e Psiquiatria

Fundamento: A doença de Parkinson (DP) é um transtorno neurodegenerativo crônico caracterizado por sintomas motores (bradicinesia, tremores, rigidez) e não motores (transtornos psicóticos, do humor e do sono). Os tratamentos farmacológicos disponíveis não são eficazes para uma parcela significativa dos pacientes. Pesquisas recentes sugerem que o fitocanabinóide canabidiol (CBD) poderia ser eficaz no tratamento de alguns sintomas da DP. Objetivos: Revisar os estudos pré-clínicos e clínicos dos efeitos do CBD nos sintomas da DP. Métodos: Revisão narrativa dos principais estudos básicos e clínicos sobre os efeitos do CBD nos sintomas da DP. Devido ao número pequeno de estudos clínicos, pesquisas com outros canabinóides também foram incluídas. Resultados: No total, 15 artigos foram incluídos na revisão: 5 estudos pré-clínicos envolvendo a administração de CBD e 10 estudos com pacientes envolvendo a administração de diferentes canabinóides (maconha, nabilona, CBD). A maioria dos estudos básicos mostraram um efeito positivo do CBD em comportamentos ou alterações bioquímicas relacionadas à DP. Estudos observacionais e clínicos com uso de maconha fumada, extrato oral de maconha, nabilona (canabinóide sintético) e CBD sugerem que estes canabinóides podem reduzir sintomas motores (bradicinesia, tremores, rigidez) e não motores (transtornos psicóticos, do humor e do sono, qualidade de vida) da DP. Além disso, são substâncias bem toleradas e com poucos efeitos adversos significativos. Conclusão: Embora o CBD tenha demonstrado resultados favoráveis tanto em estudos pré-clínicos como em estudos clínicos, estas evidências ainda não são suficientes para indicar o uso deste canabinóide em pacientes com distúrbios do DP. Novos estudos controlados devem ser realizados com diferentes dosagens de CBD para replicar estes dados.

Cannabidiol (CBD) is a natural compound with psychoactive therapeutic properties well described. Conversely, the immunological effects of CBD are still poorly explored. In this study, the potential anti-inflammatory effects and underlying mechanisms of CBD and its analog Dimethyl-Heptyl-Cannabidiol (DMH-CBD) were investigated using RAW 264.7 macrophages. CBD and DMH-CBD suppressed LPS-induced TNF production and NF-kB activity in a concentration-dependent manner. Both compounds reduced the NF-kB activity in a μM concentration range: CBD (IC50 = 15 μM) and DMH-CBD (IC50 = 38 μM). However, the concentrations of CBD that mediated NF-kB inhibition were similar to those that cause cytotoxicity (LC50 = 58 μM). Differently, DMH-CBD inhibited the NF-kB activation without cytotoxic effects at the same concentrations, although it provokes cytotoxicity at long-term exposure. The inhibitory action of the DMH-CBD on NF-kB activity was not related to the reduction in IkBα degradation or either p65 (NF-kB) translocation to the nucleus, although it decreased p38 MAP kinase phosphorylation. Additionally, 8-(3-Chlorostyryl) caffeine (CSC), an A2A antagonist, reversed the effect of DMH-CBD on NF-kB activity in a concentration-dependent manner. Collectively, our results demonstrated that CBD reduces NF-kB activity at concentrations intimately associated with those that cause cell death, whereas DMH-CBD decreases NF-kB activity at non-toxic concentrations in an A2A receptor dependent-manner.

Background Schizophrenia is a complex disabling mental disorder, and many patients present poor response to available treatments. Accumulating evidence about the role of the glutamate/nitric oxide pathway in mediating the positive and negative symptoms of schizophrenia suggests potential benefits of drugs that modulate this system. The aim of this study was to test the efficacy of isosorbide mononitrate (ISMN) as an adjunctive therapy for symptomatic outpatients with schizophrenia. Methods This was a 2-month randomized, double-blind, placebo-controlled trial with 24 schizophrenia patients. Participants were treated with ISMN 50 mg for 1 month and placebo for another month in a crossover design. The Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression Scale, Global Assessment of Functioning, and MATRICS Cognitive Consensual Battery were used for symptom assessment and arterial spin labeling was used to assess brain activation patterns. Results We found significant differences in the total, general, and positive subscales of the PANSS, Global Assessment of Functioning scores, and Clinical Global Impression scores during treatment with ISMN relative to placebo. No treatment effects were found comparing scores in the MATRICS Cognitive Consensual Battery and the negative subscale of the PANSS between the active and placebo conditions. A post hoc analysis of neuroimaging data showed reduced activity in the thalamus in subgroup of patients with severe psychopathology. Conclusions Schizophrenia patients with persistent symptoms showed significant improvement after 4 weeks of treatment with ISMN 50 mg/d compared with placebo. Isosorbide mononitrate added beneficial effects to antipsychotic treatment in terms of positive symptoms and functioning.

The incidence of chronic pain is high in the general population and it is closely related to anxiety disorders, which promote negative effects on the quality of life. The cannabinoid system has essential participation in the pain sensitivity circuit. In this perspective, cannabidiol (CBD) is considered a promising strategy for treating neuropathic pain. Our study aimed to evaluate the effects of sub-chronic systemic treatment with CBD (0.3, 3, 10, or 30 mg/kg, i.p.) in male in rats submitted to chronic constriction injury of the sciatic nerve (CCI) or not (SHAM) and assessed in nociceptive tests (von Frey, acetone, and hot plate, three days CBD's treatment) and in the open field test (OFT, two days CBD's treatment). We performed a screening immunoreactivity of CB1 and TRPV1 receptors in cortical and limbic regions tissues, which were collected after 1.5 h of behavioral tests on the 24th experimental day. This study presents a dose-response curve to understand better the effects of low doses (3 mg/kg) on CBD's antiallodynic and anxiolytic effects. Also, low doses of CBD were able to (1) reverse mechanical and thermal allodynia (cold) and hyperalgesia, (2) reverse anxious behaviors (reduction of the % of grooming and freezing time, and increase of the % of center time in the OFT) induced by chronic pain. The peripheral neuropathy promoted the increase in the expression of CB1 and TRPV1 receptors in the anterior cingulate cortex (ACC), anterior insular cortex (AIC), basolateral amygdala (BLA), dorsal hippocampus (DH), and ventral hippocampus (VH). CBD potentiated this effect in the ACC, AIC, BLA, DH, and VH regions. These results provide substantial evidence of the role of the ACC–AIC–BLA corticolimbic circuit, and BLA-VH for pain regulation. These results can be clinically relevant since they contribute to the evidence of CBD's beneficial effects on treating chronic pain and associated comorbidities such as anxiety.

Autophagy is a lysosomal catabolic process essential to cell homeostasis and is related to the neuroprotection of the central nervous system. Cannabidiol (CBD) is a non-psychotropic phytocannabinoid present in Cannabis sativa. Many therapeutic actions have been linked to this compound, including autophagy activation. However, the precise underlying molecular mechanisms remain unclear, and the downstream functional significance of these actions has yet to be determined. Here, we investigated CBD-evoked effects on autophagy in human neuroblastoma SH-SY5Y and murine astrocyte cell lines. We found that CBD-induced autophagy was substantially reduced in the presence of CB1, CB2 and TRPV1 receptor antagonists, AM 251, AM 630 and capsazepine, respectively. This result strongly indicates that the activation of these receptors mediates the autophagic flux. Additionally, we demonstrated that CBD activates autophagy through ERK1/2 activation and AKT suppression. Interestingly, CBD-mediated autophagy activation is dependent on the autophagy initiator ULK1, but mTORC1 independent. Thus, it is plausible that a non-canonical pathway is involved. Our findings collectively provide evidence that CBD stimulates autophagy signal transduction via crosstalk between the ERK1/2 and AKT kinases, which represent putative regulators of cell proliferation and survival. Furthermore, our study sheds light on potential therapeutic cannabinoid targets that could be developed for treating neurodegenerative disorders.

Objective: To assess the efficacy of cannabidiol (CBD) in the management of crack-cocaine craving and the treatment of frequent withdrawal symptoms. Methods: Thirty-one men with a diagnosis of crack-cocaine dependence were enrolled in a randomized, double-blind, placebo-controlled trial. We applied neuropsychological tests and assessed craving intensity, anxiety and depression symptoms, and substance use patterns at baseline and at the end of the trial. The participants were treated with CBD 300 mg/day or placebo for 10 days. During this period, we used a technique to induce craving and assessed the intensity of symptoms before and after the induction procedure. Results: Craving levels reduced significantly over the 10 days of the trial, although no differences were found between the CBD and placebo groups. Craving induction was successful in both groups, with no significant differences between them. Indicators of anxiety, depression, and sleep alterations before and after treatment also did not differ across groups. Conclusion: Under the conditions of this trial, CBD was unable to interfere with symptoms of crack-cocaine withdrawal. Further studies with larger outpatient samples involving different doses and treatment periods would be desirable and timely to elucidate the potential of CBD to induce reductions in crack-cocaine self-administration.

Essential tremor (ET) is a common clinical syndrome characterized by action tremors affecting both upper limbs that can compromise manual tasks' execution and impair functional and social performance. The primary pharmacological treatment is symptomatic, but effective medicines are somewhat limited. There is a clear need to find new effective therapies for the treatment of ET. Cannabidiol (CBD) is a modulator of CB1 receptor and CB1 agonists can reduce tremors in experimental models. We hypothesized that a single acute CBD intake would reduce tremors in ET patients. We performed a randomized, controlled, double-blind, crossover study on 19 patients with ET. They were 10 males and 9 females, had mean 63 years of age, and mean 23 years of disease duration and had insufficient control of their tremors with the usual pharmacological treatment. They ingested a single oral dose of CBD (300 mg) or placebo in two experimental sessions performed 2-weeks apart. Patients were evaluated immediately before and after oral ingestion (60 min and 210 min), using the Fahn-Tolosa-Marin clinical scale. There was no carryover effect. There were no significant differences in upper limb tremors score, specific motor task tremor scores (writing and drawing/pouring) or clinical impression of change after treatment with placebo or CBD. In conclusion, a single 300 mg oral dose of CBD had no significant effect on the severity of upper limb tremors of ET patients. Our findings did not exclude the possibility that chronic treatment with CBD could have a symptomatic effect.

Importance Frontline health care professionals who work with patients with COVID-19 have an increased incidence of burnout symptoms. Cannabidiol (CBD) has anxiolytic and antidepressant properties and may be capable of reducing emotional exhaustion and burnout symptoms. Objective To investigate the safety and efficacy of CBD therapy for the reduction of emotional exhaustion and burnout symptoms among frontline health care professionals working with patients with COVID-19. Design, setting, and participants This prospective open-label single-site randomized clinical trial used a 1:1 block randomization design to examine emotional exhaustion and burnout symptoms among frontline health care professionals (physicians, nurses, and physical therapists) working with patients with COVID-19 at the Ribeirao Preto Medical School University Hospital in Sao Paulo, Brazil. Participants were enrolled between June 12 and November 12, 2020. A total of 214 health care professionals were recruited and assessed for eligibility, and 120 participants were randomized in a 1:1 ratio by a researcher who was not directly involved with data collection. Interventions Cannabidiol, 300 mg (150 mg twice per day), plus standard care or standard care alone for 28 days. Main outcomes and measures The primary outcome was emotional exhaustion and burnout symptoms, which were assessed for 28 days using the emotional exhaustion subscale of the Brazilian version of the Maslach Burnout Inventory-Human Services Survey for Medical Personnel. Results A total of 120 participants were randomized to receive either CBD, 300 mg, plus standard care (treatment arm; n = 61) or standard care alone (control arm; n = 59) for 28 days. Of those, 118 participants (59 participants in each arm; 79 women [66.9%]; mean age, 33.6 years [95% CI, 32.3-34.9 years]) received the intervention and were included in the efficacy analysis. In the treatment arm, scores on the emotional exhaustion subscale of the Maslach Burnout Inventory significantly decreased at day 14 (mean difference, 4.14 points; 95% CI, 1.47-6.80 points; partial eta squared [ηp2] = 0.08), day 21 (mean difference, 4.34 points; 95% CI, 0.94-7.73 points; ηp2 = 0.05), and day 28 (mean difference, 4.01 points; 95% CI, 0.43-7.59 points; ηp2 = 0.04). However, 5 participants, all of whom were in the treatment group, experienced serious adverse events: 4 cases of elevated liver enzymes (1 critical and 3 mild, with the mild elevations reported at the final 28-day assessment) and 1 case of severe pharmacodermia. In 2 of those cases (1 with critical elevation of liver enzymes and 1 with severe pharmacodermia), CBD therapy was discontinued, and the participants had a full recovery. Conclusions and relevance In this study, CBD therapy reduced symptoms of burnout and emotional exhaustion among health care professionals working with patients during the COVID-19 pandemic. However, it is necessary to balance the benefits of CBD therapy with potential undesired or adverse effects. Future double-blind placebo-controlled clinical trials are needed to confirm the present findings. Trial registration ClinicalTrials.gov Identifier: NCT04504877.

Cannabidiol (CBD), a phytocannabinoid compound, presents antidepressant and anxiolytic-like effects in the type-1 diabetes mellitus(DM1) animal model. Although the underlying mechanism remains unknown, the type-1A serotonin receptor (5-HT1A) and cannabinoids type-1 (CB1) and type-2 (CB2) receptors seem to play a central role in mediating the beneficial effects on emotional responses. We aimed to study the involvement of these receptors on an antidepressant- and anxiolytic-like effects of CBD and on some parameters of the diabetic condition itself. After 2 weeks of the DM1 induction in male Wistar rats by streptozotocin (60 mg/kg; i.p.), animals were treated continuously for 2-weeks with the 5-HT1A receptor antagonist WAY100635 (0.1 mg/kg, i.p.), CB1 antagonist AM251 (1 mg/kg i.p.) or CB2 antagonist AM630 (1 mg/kg i.p.) before the injection of CBD (30 mg/kg, i.p.) or vehicle (VEH, i.p.) and then, they were submitted to the elevated plus-maze and forced swimming tests. Our findings show the continuous treatment with CBD improved all parameters evaluated in these diabetic animals. The previous treatment with the antagonists − 5-HT1A, CB1, or CB2 - blocked the CBD-induced antidepressant-like effect whereas only the blockade of 5-HT1A or CB1 receptors was able to inhibit the CBD-induced anxiolytic-like effect. Regarding glycemic control, only the blockade of CB2 was able to inhibit the beneficial effect of CBD in reducing the glycemia of diabetic animals. These findings indicated a therapeutic potential for CBD in the treatment of depression/anxiety associated with diabetes pointing out a complex intrinsic mechanism in which 5-HT1A, CB1, and/or CB2 receptors are differently recruited.

Cannabis can synthetize more than 400 compounds, including terpenes, flavonoids, and more than 100 phytocannabinoids. The main phytocannabinoids are Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Cannabis-based products are used as medicines in several countries. In this text, we present an overview of the main neurochemical mechanisms of action of the phytocannabinoids, especially THC and CBD. We also reviewed the indications and adverse effects of the main cannabis-based medicinal products. THC acts as a partial agonist at cannabinoid 1/2 receptors (CB1/2). It is responsible for the characteristic effects of cannabis, such as euphoria, relaxation, and changes in perceptions. THC can also produce dysphoria, anxiety, and psychotic symptoms. THC is used therapeutically in nausea and vomiting due to chemotherapy, as an appetite stimulant, and in chronic pain. CBD acts as a noncompetitive negative allosteric modulator of the CB1 receptor, as an inverse agonist of the CB2 receptor, and as an inhibitor of the reuptake of the endocannabinoid anandamide. Moreover, CBD also activates 5-HT1A serotonergic receptors and vanilloid receptors. Its use in treatment-resistant epilepsy syndromes is approved in some countries. CBD does not produce the typical effects associated with THC and has anxiolytic and antipsychotic effects. Some of the most common adverse effects of CBD are diarrhea, somnolence, nausea, and transaminase elevations (with concomitant use of antiepileptics). The mechanisms of action involved in both the therapeutic and adverse effects of the phytocannabinoids are not fully understood, involving not only the endocannabinoid system. This "promiscuous" pharmacology could be responsible for their wide therapeutic spectrum.

Objective The aim of the present study was to analyze the body sway response in specific phobia (SP) patients and healthy controls while viewing neutral, phobic, and disgusting images. Methods The participants' heart rate (HR) and skin conductance were also recorded during the procedure. Nineteen patients with arachnophobia and 19 healthy volunteers matched by age, gender, and years of education underwent a postural control test on a stabilometric platform. Results The platform recorded increased body sway in the SP group when exposed to spider images (SPI). The SP group presented increases in most parameters (SD, velocity, frequency, area, p ≤ 0.05) when viewing pictures of the SPI category. Psychometric measures of subjective anxiety (State-Trait Anxiety Inventory, STAI) and physiological states (HR; skin conductance responses; spontaneous fluctuations in skin conductance) showed increased anxiety (p ≤ 0.05) in the SP group compared to healthy volunteers. High anxiety levels were observed throughout the assessment, including the task of exposure to SPI (p ≤ 0.05). No significant effect or correlation was found between skin conductance and body sway measures (p > 0.05). Conclusions The results of the postural control test suggest the occurrence of a defensive escape response in SP, in agreement with previous evidence.