Cannabidiol for Rapid Eye Movement Sleep Behavior Disorder.

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.

Mononitrate Isosorbide as an Adjunctive Therapy in Schizophrenia: A Randomized Controlled Crossover Trial.

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.

Rimonabant effects on anxiety induced by simulated public speaking in healthy humans: a preliminary report.

OBJECTIVE: We investigated the hypothesis that rimonabant, a cannabinoid antagonist/inverse agonist, would increase anxiety in healthy subjects during a simulation of the public speaking test. METHODS: Participants were randomly allocated to receive oral placebo or 90 mg rimonabant in a double-blind design. Subjective effects were measured by Visual Analogue Mood Scale. Physiological parameters, namely arterial blood pressure and heart rate, also were monitored. RESULTS: Twelve participants received oral placebo and 12 received 90 mg rimonabant. Rimonabant increased self-reported anxiety levels during the anticipatory speech and performance phase compared with placebo. Interestingly, rimonabant did not modulate anxiety prestress and was not associated with sedation, cognitive impairment, discomfort, or blood pressure changes. CONCLUSIONS: Cannabinoid-1 antagonism magnifies the responses to an anxiogenic stimulus without interfering with the prestress phase. These data suggest that the endocannabinoid system may work on-demand to counteract the consequences of anxiogenic stimuli in healthy humans.

DNA methylation in regulatory elements of the FKBP5 and NR3C1 gene in mother-child binomials with depression.

BACKGROUND: The FKBP5 and NR3C1 genes play an important role in stress response, thus impacting mental health. Stress factor exposure in early life, such as maternal depression, may contribute to epigenetic modifications in stress response genes, increasing the susceptibility to different psychopathologies. The present study aimed to evaluate the DNA methylation profile in maternal-infant depression in regulatory regions of the FKBP5 gene and the alternative promoter of the NR3C1 gene. METHODS: We evaluated 60 mother-infant pairs. The levels of DNA methylation were analyzed by the MSRED-qPCR technique. RESULTS: We observed an increased DNA methylation profile in the NR3C1 gene promoter in children with depression and children exposed to maternal depression (p < 0.05). In addition, we observed a correlation of DNA methylation between mothers and offspring exposed to maternal depression. This correlation shows a possible intergenerational effect of maternal MDD exposure on the offspring. For FKBP5, we found a decrease in DNA methylation at intron 7 in children exposed to maternal MDD during pregnancy and a correlation of DNA methylation between mothers and children exposed to maternal MDD (p < 0.05). LIMITATIONS: Although the individuals of this study are a rare group, the sample size of the study was small, and we evaluated the DNA methylation of only one CpG site for each region. CONCLUSION: These results indicate changes in DNA methylation levels in regulatory regions of FKBP5 and NR3C1 in the mother-child MDD context and represent a potential target of studies to understand the depression etiology and how it occurs between generations.

Harmine impairs memory performance of treated rats and nontreated cagemates.

The interest in psychedelic substances as potential treatments for psychiatric disorders is increasing. The ß-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) 2022 APA, all rights reserved).

Cannabidiol for the treatment of autism spectrum disorder: hope or hype?

RATIONALE: Autism spectrum disorder (ASD) is defined as a group of neurodevelopmental disorders whose symptoms include impaired communication and social interaction, restricted and repetitive patterns of behavior, and varying levels of intellectual disability. ASD is observed in early childhood and is one of the most severe chronic childhood disorders in prevalence, morbidity, and impact on society. It is usually accompanied by attention deficit hyperactivity disorder, anxiety, depression, sleep disorders, and epilepsy. The treatment of ASD has low efficacy, possibly because it has a heterogeneous nature, and its neurobiological basis is not clearly understood. Drugs such as risperidone and aripiprazole are the only two drugs available that are recognized by the Food and Drug Administration, primarily for treating the behavioral symptoms of this disorder. These drugs have limited efficacy and a high potential for inducing undesirable effects, compromising treatment adherence. Therefore, there is great interest in exploring the endocannabinoid system, which modulates the activity of other neurotransmitters, has actions in social behavior and seems to be altered in patients with ASD. Thus, cannabidiol (CBD) emerges as a possible strategy for treating ASD symptoms since it has relevant pharmacological actions on the endocannabinoid system and shows promising results in studies related to disorders in the central nervous system. OBJECTIVES: Review the preclinical and clinical data supporting CBD's potential as a treatment for the symptoms and comorbidities associated with ASD, as well as discuss and provide information with the purpose of not trivializing the use of this drug.

Potential cannabidiol (CBD) repurposing as antibacterial and promising therapy of CBD plus polymyxin B (PB) against PB-resistant gram-negative bacilli.

This study aimed to assess the ultrapure cannabidiol (CBD) antibacterial activity and to investigate the antibacterial activity of the combination CBD + polymyxin B (PB) against Gram-negative (GN) bacteria, including PB-resistant Gram-negative bacilli (GNB). We used the standard broth microdilution method, checkerboard assay, and time-kill assay. CBD exhibited antibacterial activity against Gram-positive bacteria, lipooligosaccharide (LOS)-expressing GN diplococcus (GND) (Neisseria gonorrhoeae, Neisseria meningitidis, Moraxella catarrhalis), and Mycobacterium tuberculosis, but not against GNB. For most of the GNB studied, our results showed that low concentrations of PB (≤ 2 µg/mL) allow CBD (≤ 4 µg/mL) to exert antibacterial activity against GNB (e.g., Klebsiella pneumoniae, Escherichia coli, Acinetobacter baumannii), including PB-resistant GNB. CBD + PB also showed additive and/or synergistic effect against LOS-expressing GND. Time-kill assays results showed that the combination CBD + PB leads to a greater reduction in the number of colony forming units per milliliter compared to CBD and PB alone, at the same concentration used in combination, and the combination CBD + PB was synergistic for all four PB-resistant K. pneumoniae isolates evaluated. Our results show that CBD has translational potential and should be further explored as a repurposed antibacterial agent in clinical trials. The antibacterial efficacy of the combination CBD + PB against multidrug-resistant and extensively drug-resistant GNB, especially PB-resistant K. pneumoniae, is particularly promising.

Mitral valve prolapse and anxiety disorders.

We investigated whether there is an association between anxiety disorders and mitral valve prolapse. We compared mitral valve prolapse prevalence in individuals with panic disorder (n = 41), social anxiety disorder (n = 89) and in healthy controls (n = 102) in an attempt to overcome the biases of previous studies. Our results show no associations between panic disorder or social anxiety disorder and mitral valve prolapse, regardless of the diagnostic criteria employed, and that the relationship between these conditions seems not to be clinically relevant.

Validity of the PHQ-2 for the screening of major depression in Parkinson's disease: two questions and one important answer.

INTRODUCTION: Depression is the most common psychiatric comorbidity in Parkinson's disease (PD), but is often under-diagnosed and under-recognized. OBJECTIVES: To evaluate and compare the psychometric qualities of the Patient Health Questionnaire (PHQ-2) and the depression item of the Unified Parkinson's Disease Rating Scale (UPDRS). METHOD: Cross-sectional study conducted at a movement disorders outpatient clinic. One hundred ten patients with a diagnosis of PD without dementia were evaluated. A neurologist administered the PHQ-2 and the UPDRS, and the diagnosis of major depression was performed using the structured clinical interview for DSM disorders - clinical version. Two self-rating scales (Zung Self-rating Depression Scale and 15-item Geriatric Depression Scale) were also used. RESULTS: The prevalence of current depression in the sample was 25.5% (n = 28). The scores of the PHQ-2 discriminated between subjects with and without depression, with an area under the receiver operating characteristic curve of 0.90. The sensitivity and specificity for a cut-off score of three were 75% and 89%, respectively. The values for the depression item of the UPDRS were slightly lower. CONCLUSION: The PHQ-2 is a valid tool for screening depression in PD.

Cannabidiol prevents disruptions in sensorimotor gating induced by psychotomimetic drugs that last for 24-h with probable involvement of epigenetic changes in the ventral striatum.

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.

Is the full version of the AUDIT really necessary? Study of the validity and internal construct of its abbreviated versions.

BACKGROUND: This study was aimed at assessing the psychometric qualities of the abbreviated versions of the Alcohol Use Disorders Identification Test (AUDIT-3, AUDIT-4, AUDIT-C, AUDIT-PC, AUDIT-QF, FAST, and Five-Shot) and at comparing them to the 10-item AUDIT and the CAGE in 2 samples of Brazilian adults. METHODS: The validity and internal consistency of the scales were assessed in a sample of 530 subjects attended at an emergency department and at a Psychosocial Care Center for Alcohol and Drugs. The Structured Clinical Interview for DSM-IV was used as the diagnostic comparative measure for the predictive validity assessment. The concurrent validity between the scales was analyzed by means of Pearson's correlation coefficient. RESULTS: The assessment of the predictive validity of the abbreviated versions showed high sensitivity (of 0.78 to 0.96) and specificity (of 0.74 to 0.94) indices, with areas under the curve as elevated as those of the AUDIT (0.89 and 0.92 to screen for abuse and 0.93 and 0.95 in the screening of dependence). The CAGE presented lower indices: 0.81 for abuse and 0.87 for dependence. The analysis of the internal consistency of the AUDIT and its versions exhibited Cronbach's alpha coefficients between 0.83 and 0.94, while the coefficient for the CAGE was 0.78. Significant correlations were found between the 10-item AUDIT and its versions, ranging from 0.91 to 0.99. Again, the results for the CAGE were satisfactory (0.77), although inferior to the other instruments. CONCLUSIONS: The results obtained in this study confirm the validity of the abbreviated versions of the AUDIT for the screening of alcohol use disorders and show that their psychometric properties are as satisfactory as those of the 10-item AUDIT and the CAGE.

Proneness, urbanicity, trauma, and cannabis triggering psychotic states in large urban centers.

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.

Regional gray matter abnormalities in panic disorder: a voxel-based morphometry study.

Although abnormalities in brain structures involved in the neurobiology of fear and anxiety have been implicated in the pathophysiology of panic disorder (PD), relatively few studies have made use of voxel-based morphometry (VBM) magnetic resonance imaging (MRI) to determine structural brain abnormalities in PD. We have assessed gray matter volume in 19 PD patients and 20 healthy volunteers using VBM. Images were acquired using a 1.5 T MRI scanner, and were spatially normalized and segmented using optimized VBM. Statistical comparisons were performed using the general linear model. A relative increase in gray matter volume was found in the left insula of PD patients compared with controls. Additional structures showing differential increases were the left superior temporal gyrus, the midbrain, and the pons. A relative gray matter deficit was found in the right anterior cingulate cortex. The insula and anterior cingulate abnormalities may be relevant to the pathophysiology of PD, since these structures participate in the evaluation process that ascribes negative emotional meaning to potentially distressing cognitive and interoceptive sensory information. The abnormal brain stem structures may be involved in the generation of panic attacks.

The Influence of DAT1, COMT, and BDNF Genetic Polymorphisms on Total and Subregional Hippocampal Volumes in Early Onset Heavy Cannabis Users.

Introduction: Hippocampal neuroanatomy is affected by genetic variations in dopaminergic candidate genes and environmental insults, such as early onset of chronic cannabis exposure. Here, we examine how hippocampal total and subregional volumes are affected by cannabis use and functional polymorphisms of dopamine-relevant genes, including the catechol-O-methyltransferase (COMT), dopamine transporter (DAT1), and the brain-derived neurotrophic factor (BDNF) genes. Material and Methods: We manually traced total hippocampal volumes and automatically segmented hippocampal subregions using high-resolution MRI images, and performed COMT, DAT1, and BDNF genotyping in 59 male Caucasian young adults aged 18-30 years. These included 30 chronic cannabis users with early-onset (regular use at <16 years) and 29 age-, education-, and intelligence-matched controls. Results: Cannabis use and dopaminergic gene polymorphism had both distinct and interactive effects on the hippocampus. We found emerging alterations of hippocampal total and specific subregional volumes in cannabis users relative to controls (i.e., CA1, CA2/3, and CA4), and associations between cannabis use levels and total and specific subregional volumes. Furthermore, total hippocampal volume and the fissure subregion were affected by cannabis×DAT1 polymorphism (i.e., 9/9R and in 10/10R alleles), reflecting high and low levels of dopamine availability. Conclusion: These findings suggest that cannabis exposure alters the normal relationship between DAT1 polymorphism and the anatomy of total and subregional hippocampal volumes, and that specific hippocampal subregions may be particularly affected.

No Acute Effects of Cannabidiol on the Sleep-Wake Cycle of Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study.

Cannabidiol (CBD) is a component of Cannabis sativa that has a broad spectrum of potential therapeutic effects in neuropsychiatric and other disorders. However, few studies have investigated the possible interference of CBD on the sleep-wake cycle. The aim of the present study was to evaluate the effect of a clinically anxiolytic dose of CBD on the sleep-wake cycle of healthy subjects in a crossover, double-blind design. Twenty-seven healthy volunteers that fulfilled the eligibility criteria were selected and allocated to receive either CBD (300 mg) or placebo in the first night in a double-blind randomized design (one volunteer withdrew from the study). In the second night, the same procedure was performed using the substance that had not been administered in the previous occasion. CBD or placebo were administered 30 min before the start of polysomnography recordings that lasted 8 h. Cognitive and subjective measures were performed immediately after polysomnography to assess possible residual effects of CBD. The drug did not induce any significant effect (p > 0.05). Different from anxiolytic and antidepressant drugs such as benzodiazepines and selective serotonin reuptake inhibitors, acute administration of an anxiolytic dose of CBD does not seem to interfere with the sleep cycle of healthy volunteers. The present findings support the proposal that CBD do not alter normal sleep architecture. Future studies should address the effects of CBD on the sleep-wake cycle of patient populations as well as in clinical trials with larger samples and chronic use of different doses of CBD. Such studies are desirable and opportune.

A Conversion of Oral Cannabidiol to Delta9-Tetrahydrocannabinol Seems Not to Occur in Humans.

Cannabidiol (CBD), a major cannabinoid of hemp, does not bind to CB1 receptors and is therefore devoid of psychotomimetic properties. Under acidic conditions, CBD can be transformed to delta9-tetrahydrocannabinol (THC) and other cannabinoids. It has been argued that this may occur also after oral administration in humans. However, the experimental conversion of CBD to THC and delta8-THC in simulated gastric fluid (SGF) is a highly artificial approach that deviates significantly from physiological conditions in the stomach; therefore, SGF does not allow an extrapolation to in vivo conditions. Unsurprisingly, the conversion of oral CBD to THC and its metabolites has not been observed to occur in vivo, even after high doses of oral CBD. In addition, the typical spectrum of side effects of THC, or of the very similar synthetic cannabinoid nabilone, as listed in the official Summary of Product Characteristics (e.g., dizziness, euphoria/high, thinking abnormal/concentration difficulties, nausea, tachycardia) has not been observed after treatment with CBD in double-blind, randomized, controlled clinical trials. In conclusion, the conversion of CBD to THC in SGF seems to be an in vitro artifact.

Cannabidiol Is a Potential Therapeutic for the Affective-Motivational Dimension of Incision Pain in Rats.

Background: Pain involves different brain regions and is critically determined by emotional processing. Among other areas, the rostral anterior cingulate cortex (rACC) is implicated in the processing of affective pain. Drugs that interfere with the endocannabinoid system are alternatives for the management of clinical pain. Cannabidiol (CBD), a phytocannabinoid found in Cannabis sativa, has been utilized in preclinical and clinical studies for the treatment of pain. Herein, we evaluate the effects of CBD, injected either systemically or locally into the rACC, on mechanical allodynia in a postoperative pain model and on the negative reinforcement produced by relief of spontaneous incision pain. Additionally, we explored whether CBD underlies the reward of pain relief after systemic or rACC injection. Methods and Results: Male Wistar rats were submitted to a model of incision pain. All rats had mechanical allodynia, which was less intense after intraperitoneal CBD (3 and 10 mg/kg). Conditioned place preference (CPP) paradigm was used to assess negative reinforcement. Intraperitoneal CBD (1 and 3 mg/kg) inverted the CPP produced by peripheral nerve block even at doses that do not change mechanical allodynia. CBD (10 to 40 nmol/0.25 µL) injected into the rACC reduced mechanical allodynia in a dose-dependent manner. CBD (5 nmol/0.25 µL) did not change mechanical allodynia, but reduced peripheral nerve block-induced CPP, and the higher doses inverted the CPP. Additionally, CBD injected systemically or into the rACC at doses that did not change the incision pain evoked by mechanical stimulation significantly produced CPP by itself. Therefore, a non-rewarding dose of CBD in sham-incised rats becomes rewarding in incised rats, presumably because of pain relief or reduction of pain aversiveness. Conclusion: The study provides evidence that CBD influences different dimensions of the response of rats to a surgical incision, and the results establish the rACC as a brain area from which CBD evokes antinociceptive effects in a manner similar to the systemic administration of CBD. In addition, the study gives further support to the notion that the sensorial and affective dimensions of pain may be differentially modulated by CBD.

Inverted U-Shaped Dose-Response Curve of the Anxiolytic Effect of Cannabidiol during Public Speaking in Real Life.

The purpose of this study was to investigate whether the anxiolytic effect of cannabidiol (CBD) in humans follows the same pattern of an inverted U-shaped dose-effect curve observed in many animal studies. Sixty healthy subjects of both sexes aged between 18 and 35 years were randomly assigned to five groups that received placebo, clonazepam (1 mg), and CBD (100, 300, and 900 mg). The subjects were underwent a test of public speaking in a real situation (TPSRS) where each subject had to speak in front of a group formed by the remaining participants. Each subject completed the anxiety and sedation factors of the Visual Analog Mood Scale and had their blood pressure and heart rate recorded. These measures were obtained in five experimental sessions with 12 volunteers each. Each session had four steps at the following times (minutes) after administration of the drug/placebo, as time 0: -5 (baseline), 80 (pre-test), 153 (speech), and 216 (post-speech). Repeated-measures analyses of variance showed that the TPSRS increased the subjective measures of anxiety, heart rate, and blood pressure. Student-Newman-Keuls test comparisons among the groups in each phase showed significant attenuation in anxiety scores relative to the placebo group in the group treated with clonazepam during the speech phase, and in the clonazepam and CBD 300 mg groups in the post-speech phase. Clonazepam was more sedative than CBD 300 and 900 mg and induced a smaller increase in systolic and diastolic blood pressure than CBD 300 mg. The results confirmed that the acute administration of CBD induced anxiolytic effects with a dose-dependent inverted U-shaped curve in healthy subjects, since the subjective anxiety measures were reduced with CBD 300 mg, but not with CBD 100 and 900 mg, in the post-speech phase.