The anxiolytic effect of cannabidiol depends on the nature of the trauma when patients with post-traumatic stress disorder recall their trigger event

Objectives: We assessed whether administering cannabidiol (CBD) before recalling the traumatic event that triggered their disorder attenuates anxiety in patients with post-traumatic stress disorder (PTSD). As an exploratory pilot analysis, we also investigated whether this effect depends on the nature of the event (sexual vs. nonsexual trauma). Methods: Thirty-three patients of both sexes with PTSD were recruited and randomized 1:1 into two groups. One group received oral CBD (300 mg), and the other received a placebo before listening to a digital audio playback of their previously recorded report of the trigger event. Subjective and physiological measurements were taken before and after recall. We analyzed the data in two subsamples: trigger events involving sexual and nonsexual trauma. Results: In the nonsexual trauma group, the differences between measurements before and after recall were significantly smaller with CBD than placebo; this held true for anxiety and cognitive impairment. However, in the sexual trauma group, the differences were non-significant for both measurements. Conclusion: A single dose of CBD (300mg) attenuated the increased anxiety and cognitive impairment induced by recalling a traumatic event in patients with PTSD when the event involved nonsexual trauma.

Effect of two oral formulations of cannabidiol on responses to emotional stimuli in healthy human volunteers: pharmaceutical vehicle matters

Objective: To compare plasma concentrations of cannabidiol (CBD) following oral administration of two formulations of the drug (powder and dissolved in oil), and to evaluate the effects of these distinct formulations on responses to emotional stimuli in healthy human volunteers. Methods: In a randomized, double-blind, placebo-controlled, parallel-group design, 45 healthy male volunteers were randomly assigned to three groups of 15 subjects that received either 150 mg of CBD powder; 150 mg of CBD dissolved in corn oil; or placebo. Blood samples were collected at different times after administration, and a facial emotion recognition task was completed after 150 min. Results: There were no significant differences across groups in the subjective and physiological measures, nor in the facial emotion recognition task. However, groups that received the drug showed statistically significant differences in baseline measures of plasma CBD, with a significantly greater difference in favor of the oil formulation. Conclusion: When administered as a single 150-mg dose, neither formulation of oral CBD altered responses to emotional stimuli in healthy subjects. The oil-based CBD formulation resulted in more rapid achievement of peak plasma level, with an approximate fourfold increase in oral bioavailability.

Nitrous oxide as an adjunctive therapy in major depressive disorder: a randomized controlled double-blind pilot trial

Objective: Major depressive disorder (MDD) is related to glutamatergic dysfunction. Antagonists of glutamatergic N-methyl-D-aspartate receptor (NMDAR), such as ketamine, have antidepressant properties. Nitrous oxide (N2O) is also a NMDAR antagonist. Thus, this study aimed to evaluate the effects of augmenting antidepressant treatment with N2O. Methods: This double blind, placebo-controlled randomized parallel pilot trial was conducted from June 2016 to June 2018 at the Hospital das Clínicas, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo. Twenty-three subjects with MDD (aged 18 to 65, on antidepressants, with a score > 17 on the 17-item-Hamilton Depression Rating Scale [HAM-D17]) received 50% N2O (n=12; 37.17±13.59 years) or placebo (100% oxygen) (n=11; 37.18±12.77 years) for 60 minutes twice a week for 4 weeks. The primary outcome was changes in HAM-D17 from baseline to week 4. Results: Depressive symptoms improved significantly in the N2O group (N2O: from 22.58±3.83 to 5.92±4.08; placebo: from 22.44±3.54 to 12.89±5.39, p < 0.005). A total of 91.7% and 75% of the N2O group subjects achieved response (≥ 50% reduction in HAM-D17 score) and remission (HAM-D17 < 7), respectively. The predominant adverse effects of N2O treatment were nausea, vomiting, and headache. Conclusion: N2O treatment led to a statistically significant reduction in HAM-D17 scores compared to placebo. Clinical trial registration: Brazilian Register of Clinical Trials, RBR-5rz5ch

Increased body sway in phobic patients exposed to images of spiders

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.

Cannabidiol for the treatment of crack-cocaine craving: an exploratory double-blind study

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.

Evaluation of relationships between presence of adhesio interthalamica and cannabis use in first-episode psychosis: a magnetic resonance imaging investigation

ABSTRACT Recent studies suggested that cannabis use influences on the emergence of psychosis by disrupting neurodevelopmental processes that occur during adolescence and early adulthood and which are reflected on brain anatomical changes detectable with MRI. However, no MRI studies have investigated whether intrauterine neurodevelopmental abnormalities also interact with later cannabis use to influence on psychosis risk. We investigated differences between first-episode psychosis (FEP) patients with history of cannabis use (FEPC+, n=28), FEP subjects without cannabis use (FEPC-, n=78) and healthy controls (n=80) in regard to the frequency of absent or short Adhesio Interthalamica (AI), a well-established marker of intrauterine neurodevelopment. The FEPC+ subgroup had a significantly lower prevalence of absent AI than FEPC- subjects, as well as a lack of a significantly shorter AI length compared to controls (as found in FEPC- subjects). These preliminary results show that psychosis subjects with cannabis use present a low rather than high frequency of absent AI, suggesting that fixed intrauterine neurodevelopmental abnormalities may not be associated with cannabis use later in life to influence on the emergence of psychosis. This is consistent with a view that multiple different etiological processes may lead to similar clinical presentations in patients with FEP.

Biological bases for a possible effect of cannabidiol in Parkinson's disease

Current pharmacotherapy of Parkinson's disease (PD) is palliative and unable to modify the progression of neurodegeneration. Treatments that can improve patients' quality of life with fewer side effects are needed, but not yet available. Cannabidiol (CBD), the major non-psychotomimetic constituent of cannabis, has received considerable research attention in the last decade. In this context, we aimed to critically review the literature on potential therapeutic effects of CBD in PD and discuss clinical and preclinical evidence supporting the putative neuroprotective mechanisms of CBD. We searched MEDLINE (via PubMed) for indexed articles published in English from inception to 2019. The following keywords were used: cannabis; cannabidiol and neuroprotection; endocannabinoids and basal ganglia; Parkinson's animal models; Parkinson's history; Parkinson's and cannabidiol. Few studies addressed the biological bases for the purported effects of CBD on PD. Six preclinical studies showed neuroprotective effects, while three targeted the antidyskinetic effects of CBD. Three human studies have tested CBD in patients with PD: an open-label study, a case series, and a randomized controlled trial. These studies reported therapeutic effects of CBD on non-motor symptoms. Additional research is needed to elucidate the potential effectiveness of CBD in PD and the underlying mechanisms involved.

Personality Inventory for DSM-5 (PID-5): cross-cultural adaptation and content validity in the Brazilian context / Inventário de Personalidade para o DSM-5 (PID-5): adaptação transcultural e validade de conteúdo para o contexto brasileiro

Abstract Objective To describe the process of cross-cultural adaptation of the Personality Inventory for DSM-5 (PID-5) to the Brazilian context. Methods Cross-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. Results All 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. Conclusion The 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.

Resumo Objetivo Apresentar o processo de adaptação transcultural do Personality Inventory for DSM-5 (PID-5) para o contexto brasileiro. Métodos A 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. Resultados Todos 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. Conclusão A 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.

Acute effects of ayahuasca in a juvenile non-human primate model of depression

Objective: The incidence rate of major depression in adolescents reaches approximately 14%. This disorder is usually recurrent, without remission of symptoms even after pharmacological treatment, and persists throughout adult life. Since the effects of antidepressants take approximately 2 weeks to begin, new pharmacological therapies are under continuous exploration. Recent evidence suggests that psychedelics could produce rapid antidepressant effects. In this study, we evaluated the potential antidepressant effects of ayahuasca in a juvenile non-human primate model of depression. Methods: While living with their families, juvenile marmosets (8 males; 7 females) were observed on alternate days for four weeks during a baseline phase. This was followed by 8 weeks of an induced depressive state protocol, the social isolated context (IC), in which the animals were monitored in the first and last weeks. Subsequently, five males and four females were randomly selected for treatment, first with a single administration of saline vehicle (1.67 mL/300 g of body weight, via gavage), followed by a single dose of ayahuasca (1.67 mL/300 g of body weight, via gavage). Both phases lasted 1 week and the animals were monitored daily. A third week of sampling was called the tardive-pharmacological effects phase. In all phases the marmosets were assessed for behavior, fecal cortisol levels, and body weight. Results: After IC, the animals presented typical hypocortisolemia, but cortisol recovered to baseline levels 24 h after an acute dose of ayahuasca; this recovery was not observed in vehicle-treated animals. Additionally, in males, ayahuasca, but not the vehicle, reduced scratching, a stereotypic behavior, and increased feeding. Ayahuasca treatment also improved body weight to baseline levels in both sexes. The ayahuasca-induced behavioral response had long-term effects (14 days). Thus, in this translational juvenile animal model of depression, ayahuasca presented beneficial effects. Conclusions: These results can contribute to the validation of ayahuasca as an antidepressant drug and encourage new studies on psychedelic drugs as a tool for treating mood disorders, including for adolescents with early-onset depression.

Long-term effects of ayahuasca in patients with recurrent depression: a 5-year qualitative follow-up

Background Ayahuasca is a botanical hallucinogenic preparation traditionally used by indigenous populations of Northwestern Amazonian countries for ritual and therapeutic purposes. It is rich in β-carboline alkaloids and N,N-dimethyltryptamine (DMT). Preclinical, observational, and experimental studies suggest that ayahuasca and its alkaloids have anxiolytic and antidepressive effects. We recently reported in an open-label trial that ayahuasca administration was associated with significant decreases in depression symptoms for 2-3 weeks after the experimental session in 17 patients with treatment-resistant major depressive disorder. Objectives To investigate if the experiment had any long-lasting effects on patients Methods Eight patients were interviewed 4 to 7 years after ayahuasca intake. Results Our results suggest that ayahuasca was well tolerated and that symptom reductions were limited to a few weeks. Importantly, most patients believed that the experience was among the most important of their lives, even 4-7 years later. Discussion To the best of our knowledge, this is the first long-term follow-up of a clinical sample that participated in an ayahuasca trial. Further studies with different and repeated dosing should be designed to further explore the antidepressive and anxiolytic effects of ayahuasca.

Effects of sodium nitroprusside in the prevention of schizophrenia-like symptoms induced by ketamine - A translational double-blind study

Abstract Background: Recent evidence has shown improvements in schizophrenia symptoms after the infusion of sodium nitroprusside (SNP), a nitric oxide (NO) donor. In the rat model of schizophrenia using ketamine injection, pretreatment with SNP seems to prevent behavioral changes associated with positive symptoms for up to one week. Objective: We investigated whether SNP would have preventative effects on psychogenic symptoms induced by ketamine in healthy subjects. Methods: Healthy subjects (N = 38) were assigned to distinct groups that received SNP in different doses (0.15, 0.25, and 0.5 mcg/kg/min). First, participants received an infusion of SNP or placebo over 75 minutes. After 10 minutes, they were injected for 1 minute with a bolus of 0.26 mg/kg of ketamine and a maintenance dose was started 5 minutes later, with 0.25 mg/kg/h of ketamine for 50 minutes. Results: Ketamine-induced psychopathological alterations induced were reduced by SNP, as assessed with the Brief Psychological Rating Scale. Scores in the objective subscale of the Clinician-Administered Dissociative States Scale were also lower in SNP sessions compared to placebo. SNP had protective effects against deterioration in facial emotion and identity recognition tasks induced by ketamine. Discussion: Our findings support the view that SNP has preventative properties against psychotic manifestations.

Ayahuasca: what mental health professionals need to know

Abstract Background Ayahuasca is a psychoactive ethnobotanical concoction that has been used for decades by indigenous groups of the Northwestern Amazon and by syncretic religious organizations for ritual and therapeutic purposes. In the last two decades, it is being used worldwide in evolving practices. Ayahuasca seem to therapeutic effects, but controlled studies are lacking. Moreover, its safety and toxicity are not completely understood. Objectives To present an overview of the effects of ayahuasca based on the most recent human studies. Methods Narrative review. Results Ayahuasca administration in controlled settings appears to be safe from a subjective and physiological perspective, with few adverse reactions being reported. More frequent adverse reactions occur in non-controlled settings. Prolonged psychotic reactions are rare and seem to occur especially in susceptible individuals. Ayahuasca showed antidepressive, anxiolytic, and antiaddictive effects in animal models, observational studies, and in open-label and controlled studies. Discussion Ayahuasca administration in controlled settings appear to be safe. Moreover, ayahuasca seem to have therapeutic effects for treatment-resistant psychiatric disorders that should be further investigated in randomized controlled clinical trials. However, medical complications and cases of prolonged psychotic reactions have been reported, and people with personal or family history of psychotic disorders should avoid ayahuasca intake.

Arterial spin labeling in patients with schizophrenia: a systematic review

Abstract Background: Neuroimaging studies are an invaluable source of information about the physiopathology of schizophrenia. Arterial spin labeling (ASL) is a new magnetic resonance technique (MRI) that is able to effectively evaluate brain function without the use of radiation. Objective: To make a systematic review of studies using ASL to compare resting-state regional cerebral blood flow (rCBF) patterns in patients with schizophrenia and healthy controls. Methods: Original articles were searched for on PubMed, Scopus, Web of Science and PsycINFO electronic databases. The search terms used were 'arterial', 'spin', 'labeling', and 'schizophrenia'. Only studies comparing resting-state rCBF were included, a qualitative synthesis was then performed. Results: Ten articles were included in the review among a total of 22. Decreased rCBF in schizophrenia patients was described in the anterior cingulate, cuneus, fusiform gyrus, frontal lobe, left middle frontal gyrus, inferior frontal gyrus, lingual gyrus, middle occipital gyrus, and parietal lobe. The putamen was the only region with increased rCBF in schizophrenia. Discussion: The evidence of the studies reviewed lends support to the concept of hipofrontality in schizophrenia. rCBF alterations were found in regions classically associated with schizophrenia. ASL seems to be valid, and reliable tool to assess schizophrenia.

Antidepressive and anxiolytic effects of ayahuasca: a systematic literature review of animal and human studies

Objective: To conduct a systematic literature review of animal and human studies reporting anxiolytic or antidepressive effects of ayahuasca or some of its isolated alkaloids (dimethyltryptamine, harmine, tetrahydroharmine, and harmaline). Methods: Papers published until 3 April 2015 were retrieved from the PubMed, LILACS and SciELO databases following a comprehensive search strategy and using a predetermined set of criteria for article selection. Results: Five hundred and fourteen studies were identified, of which 21 met the established criteria. Studies in animals have shown anxiolytic and antidepressive effects of ayahuasca, harmine, and harmaline, and experimental studies in humans and mental health assessments of experienced ayahuasca consumers also suggest that ayahuasca is associated with reductions in anxiety and depressive symptoms. A pilot study reported rapid antidepressive effects of a single ayahuasca dose in six patients with recurrent depression. Conclusion: Considering the need for new drugs that produce fewer adverse effects and are more effective in reducing anxiety and depression symptomatology, the described effects of ayahuasca and its alkaloids should be further investigated.

Avaliação do papel do sistema canabidiol em um modelo de lesão renal por isquemia/reperfusão em animais / Evaluation of the role of the cannabidiol system in an animal model of ischemia/reperfusion kidney injury

RESUMO Objetivo: Investigar os efeitos da administração de canabidiol em um modelo de isquemia/reperfusão renal em animais. Métodos: Foi induzida uma lesão renal, por meio de 45 minutos de isquemia renal seguida por reperfusão. Administrou-se canabidiol (5mg/kg) imediatamente após a reperfusão. Resultados: A isquemia/reperfusão aumentou os níveis de interleucina 1 e fator de necrose tumoral, o que foi atenuado pelo tratamento com canabidiol. Além disso, o canabidiol foi capaz de diminuir o dano oxidativo de lipídios e proteínas, mas não os níveis de nitrito/nitrato. A lesão renal após isquemia/reperfusão pareceu ser independente da expressão dos receptores canabidiol-1 e canabidiol-2, já que não houve aumento significante desses receptores após a reperfusão. Conclusão: O tratamento com canabidiol teve um efeito protetor contra a inflamação e o dano oxidativo em um modelo de isquemia/reperfusão renal. Esses efeitos parecem não ocorrer via ativação dos receptores canabidiol-1/canabidiol-2.

ABSTRACT Objective: This work aimed to investigate the effects of the administration of cannabidiol in a kidney ischemia/reperfusion animal model. Methods: Kidney injury was induced by 45 minutes of renal ischemia followed by reperfusion. Cannabidiol (5mg/kg) was administered immediately after reperfusion. Results: Ischemia/reperfusion increased the IL-1 and TNF levels, and these levels were attenuated by cannabidiol treatment. Additionally, cannabidiol was able to decrease lipid and protein oxidative damage, but not the nitrite/nitrate levels. Kidney injury after ischemia/reperfusion seemed to be independent of the cannabidiol receptor 1 and cannabidiol receptor 2 (CB1 and CB2) expression levels, as there was no significant increase in these receptors after reperfusion. Conclusion: The cannabidiol treatment had a protective effect against inflammation and oxidative damage in the kidney ischemia/reperfusion model. These effects seemed to be independent of CB1/CB2 receptor activation.