Serotonin 5-HT1A Receptor Research Articles

Purpurascenines A-C, Azepino-Indole Alkaloids from Cortinarius purpurascens: Isolation, Biosynthesis, and Activity Studies on the 5-HT2A Receptor.

Three previously undescribed azepino-indole alkaloids, named purpurascenines A-C (1-3), together with the new-to-nature 7-hydroxytryptophan (4) as well as two known compounds, adenosine (5) and riboflavin (6), were isolated from fruiting bodies of Cortinarius purpurascens Fr. (Cortinariaceae). The structures of 1-3 were elucidated based on spectroscopic analyses and ECD calculations. Furthermore, the biosynthesis of purpurascenine A (1) was investigated by in vivo experiments using 13C-labeled sodium pyruvate, alanine, and sodium acetate incubated with fruiting bodies of C. purpurascens. The incorporation of 13C into 1 was analyzed using 1D NMR and HRESIMS methods. With [3-13C]-pyruvate, a dramatic enrichment of 13C was observed, and hence a biosynthetic route via a direct Pictet-Spengler reaction between α-keto acids and 7-hydroxytryptophan (4) is suggested for the biosynthesis of purpurascenines A-C (1-3). Compound 1 exhibits no antiproliferative or cytotoxic effects against human prostate (PC-3), colorectal (HCT-116), and breast (MCF-7) cancer cells. An in silico docking study confirmed the hypothesis that purpurascenine A (1) could bind to the 5-HT2A serotonin receptor's active site. A new functional 5-HT2A receptor activation assay showed no functional agonistic but some antagonistic effects of 1 against the 5-HT-dependent 5-HT2A activation and likely antagonistic effects on putative constitutive activity of the 5-HT2A receptor.

0642 Effect of Iloperidone on Sleep Symptoms in Bipolar Patients with Manic and Mixed Episodes: A Randomized, Placebo Controlled Study

Abstract Introduction Iloperidone, a dopamine D2 receptor and serotonin 5HT2A receptor antagonist, was evaluated for the treatment of acute manic and mixed episodes associated with bipolar I disorder in adults in a phase 3 clinical trial. A core symptom of bipolar I disorder is disturbance in sleep. During manic episodes this commonly presents as reduced need for sleep with studies finding that 69%–99% of bipolar individuals report a lessened need for sleep or difficulties in falling and/or staying asleep. Here we present a post hoc analysis evaluating iloperidone effects on the sleep component of the Young Mania Rating Scale (YMRS) in patients with bipolar I disorder which addresses both sleep and the reduced need for sleep in that component. Methods This was a multicenter, randomized, double-blind, placebo-controlled, parallel-group study of iloperidone in patients with acute manic or mixed episodes associated with bipolar I disorder. Patients received four weeks of double-blind treatment. The primary analysis demonstrating an overall improvement from baseline YMRS score in iloperidone assigned patients versus placebo assigned patients (p = 0.000008) at the end of the study (week 4). A YMRS item level analysis evaluated changes on YMRS single items including the sleep component in the intent-to-treat population (N = 392) using a mixed-effects model for repeated measures approach. Results The least squares mean difference (LSMD) in change from baseline to day 28 was statistically significant on the YMRS sleep component in favor of iloperidone versus placebo (iloperidone = -1.26, placebo = -0.95; p = 0.008). Conclusion In addition to improving overall mania symptoms as reported by the YMRS, improvements were also seen in iloperidone treated patients in the sleep component which at baseline included assessments of both decreased sleep and decreased need or denial of the need for sleep. Support (if any) This work was supported by Vanda Pharmaceuticals Inc.

Cannabidiol and mitragynine exhibit differential interactive effects in the attenuation of paclitaxel-induced mechanical allodynia, acute antinociception, and schedule-controlled responding in mice.

For many chemotherapy patients peripheral neuropathy is a debilitating side effect. Mitragyna speciosa (kratom) contains the alkaloid mitragynine (MG), which produces analgesia in multiple preclinical pain models. In humans, anecdotal reports suggest cannabidiol (CBD) may enhance kratom-related analgesia. We examined the interactive activity of MG and CBD in a mouse chemotherapy-induced peripheral neuropathy (CIPN) model. We also examined MG + CBD in acute antinociception and schedule-controlled responding assays, as well as examined underlying receptor mechanisms. Male and female C57BL/6J mice received a cycle of intraperitoneal (ip) paclitaxel injections (cumulative dose 32mg/kg). The von Frey assay was utilized to assess CIPN allodynia. In paclitaxel-naïve mice, schedule-controlled responding for food was conducted under a fixed ratio (FR)-10, and hot plate antinociception was examined. MG dose-relatedly attenuated CIPN allodynia (ED50 102.96mg/kg, ip), reduced schedule-controlled responding (ED50 46.04mg/kg, ip), and produced antinociception (ED50 68.83mg/kg, ip). CBD attenuated allodynia (ED50 85.14mg/kg, ip) but did not decrease schedule-controlled responding or produce antinociception. Isobolographic analysis revealed 1:1, 3:1 MG + CBD mixture ratios additively attenuated CIPN allodynia. All combinations decreased schedule-controlled responding and produced antinociception. WAY-100635 (serotonin 5-HT1A receptor antagonist) pretreatment (0.01mg/kg, ip) antagonized CBD anti-allodynia. Naltrexone (pan opioid receptor antagonist) pretreatment (0.032mg/kg, ip) antagonized MG anti-allodynia and acute antinociception but produced no change in MG-induced decreased schedule-controlled behavior. Yohimbine (α2 receptor antagonist) pretreatment (3.2mg/kg, ip) antagonized MG anti-allodynia and produced no change in MG-induced acute antinociception or decreased schedule-controlled behavior. Although more optimization is needed, these data suggest CBD combined with MG may be useful as a novel CIPN therapeutic.

Ulotaront: review of preliminary evidence for the efficacy and safety of a TAAR1 agonist in schizophrenia.

Ulotaront is a trace amine-associated receptor 1 (TAAR1) agonist in Phase 3 clinical development for the treatment of schizophrenia. Ulotaront was discovered through a unique, target-agnostic approach optimized to identify drug candidates lacking D2 and 5-HT2A receptor antagonism, while demonstrating an antipsychotic-like phenotypic profile in vivo. The mechanism of action (MOA) of ulotaront is thought to be mediated by agonism at TAAR1 and serotonin 5-HT1A receptors. Ulotaront has completed two Phase 2 trials (4-week acute study and 26-week open-label extension) which led to Breakthrough Therapy Designation from the US Food and Drug Administration for the treatment of schizophrenia. In the double-blind, placebo-controlled, acute study, ulotaront was associated with significant (p < 0.001) improvement in Positive and Negative Syndrome Scale (PANSS) total score (effect size [ES]: 0.45), with improvements vs. placebo also observed across secondary endpoints. Post-hoc analyses of the acute trial revealed additional evidence to support the effect of ulotaront on negative symptoms. In the 4-week study, ulotaront was well-tolerated, with an incidence of adverse events (AEs) numerically lower compared to placebo (45.8% vs. 50.4%; with a number needed to harm [NNH] for individual ulotaront AEs all > 40). The open-label extension demonstrated further improvement across schizophrenia symptoms and confirmed the tolerability of ulotaront, with a 6-month completion rate of 67%. Based on current data, ulotaront shows potential to be a first-in-class TAAR1 agonist for the treatment of schizophrenia with a safety and efficacy profile distinct from current antipsychotics.

Psychedelics as Transformative Therapeutics.

Over the past decade, psychedelic compounds have emerged as potentially transformative therapeutics for a variety of intractable neuropsychiatric conditions. However, historically most of the basic science has utilized these compounds as probes to interrogate various endogenous neurotransmitter systems-mainly the serotonin 5-HT2A receptor. With the renewed interest in utilizing these compounds as therapeutics and the explosion in clinical trials, psychedelics have been purported to treat many neuropsychiatric disorders, including depression, cluster headaches, migraines, anxiety, and obsessive-compulsive disorder. It is therefore imperative to understand the biology and pharmacology behind their therapeutic mechanisms as well as expose any potential pitfalls in their widespread use as treatments. This review covers the latest advances in understanding the biological mechanisms, the newest efforts in drug discovery, and potential pitfalls when it comes to utilizing this class of compounds as emerging therapeutics.

A multicenter, double-blind, placebo-controlled, randomized, Phase 1b crossover trial comparing two doses of ulotaront with placebo in the treatment of narcolepsy-cataplexy

BackgroundUlotaront (SEP-363856) is a novel agonist at trace amine-associated receptor 1 and serotonin 5-HT1A receptors in clinical development for the treatment of schizophrenia. Previous studies demonstrated ulotaront suppresses rapid eye movement (REM) sleep in both rodents and healthy volunteers. We assessed acute and sustained treatments of ulotaront on REM sleep and symptoms of cataplexy and alertness in subjects with narcolepsy-cataplexy. MethodsIn a multicenter, double-blind, placebo-controlled, randomized, 3-way crossover study, ulotaront was evaluated in 16 adults with narcolepsy-cataplexy. Two oral doses of ulotaront (25 mg and 50 mg) were administered daily for 2 weeks and compared with matching placebo (6-treatment sequence, 3-period, 3-treatment). ResultsAcute treatment with both 25 mg and 50 mg of ulotaront reduced minutes spent in nighttime REM compared to placebo. A sustained 2-week administration of both doses of ulotaront reduced the mean number of short-onset REM periods (SOREMPs) during daytime multiple sleep latency test (MSLT) compared to placebo. Although cataplexy events decreased from the overall mean baseline during the 2-week treatment period, neither dose of ulotaront statistically separated from placebo (p = 0.76, 25 mg; p = 0.82, 50 mg), and no significant improvement in patient and clinician measures of sleepiness from baseline to end of the 2-week treatment period occurred in any treatment group. ConclusionsAcute and sustained treatment with ulotaront reduced nighttime REM duration and daytime SOREMPs, respectively. The effect of ulotaront on suppression of REM did not demonstrate a statistical or clinically meaningful effect in narcolepsy-cataplexy. RegistrationClinicalTrials.gov identifier: NCT05015673.

Anxiolytic-like Effects and Quantitative EEG Profile of Palmitone Induces Responses Like Buspirone Rather Than Diazepam as Clinical Drugs.

Anxiety is a mental disorder with a growing worldwide incidence due to the SARS-CoV-2 virus pandemic. Pharmacological therapy includes drugs such as benzodiazepines (BDZs) or azapirones like buspirone (BUSP) or analogs, which unfortunately produce severe adverse effects or no immediate response, respectively. Medicinal plants or their bioactive metabolites are a shared global alternative to treat anxiety. Palmitone is one active compound isolated from Annona species due to its tranquilizing activity. However, its influence on neural activity and possible mechanism of action are unknown. In this study, an electroencephalographic (EEG) spectral power analysis was used to corroborate its depressant activity in comparison with the anxiolytic-like effects of reference drugs such as diazepam (DZP, 1 mg/kg) and BUSP (4 mg/kg) or 8-OH-DPAT (1 mg/kg), alone or in the presence of the GABAA (picrotoxin, PTX, 1 mg/kg) or serotonin 5-HT1A receptor antagonists (WAY100634, WAY, 1 mg/kg). The anxiolytic-like activity was assayed using the behavioral response of mice employing open-field, hole-board, and plus-maze tests. EEG activity was registered in both the frontal and parietal cortex, performing a 10 min baseline and 30 min recording after the treatments. As a result, anxiety-like behavior was significantly decreased in mice administered with palmitone, DZP, BUSP, or 8-OH-DPAT. The effect of palmitone was equivalent to that produced by 5-HT1A receptor agonists but 50% less effective than DZP. The presence of PTX and WAY prevented the anxiolytic-like response of DZP and 8-OH-DPAT, respectively. Whereas only the antagonist of the 5-HT1A receptor (WAY) inhibited the palmitone effects. Palmitone and BUSP exhibited similar changes in the relative power bands after the spectral power analysis. This response was different to the changes induced by DZP. In conclusion, brain electrical activity was associated with the anxiolytic-like effects of palmitone implying a serotoninergic rather than a GABAergic mechanism of action.

5HT1AR-FGFR1 Heteroreceptor Complexes Differently Modulate GIRK Currents in the Dorsal Hippocampus and the Dorsal Raphe Serotonin Nucleus of Control Rats and of a Genetic Rat Model of Depression.

The midbrain raphe serotonin (5HT) neurons provide the main ascending serotonergic projection to the forebrain, including hippocampus, which has a role in the pathophysiology of depressive disorder. Serotonin 5HT1A receptor (R) activation at the soma-dendritic level of serotonergic raphe neurons and glutamatergic hippocampal pyramidal neurons leads to a decrease in neuronal firing by activation of G protein-coupled inwardly-rectifying potassium (GIRK) channels. In this raphe-hippocampal serotonin neuron system, the existence of 5HT1AR-FGFR1 heteroreceptor complexes has been proven, but the functional receptor-receptor interactions in the heterocomplexes have only been investigated in CA1 pyramidal neurons of control Sprague Dawley (SD) rats. In the current study, considering the impact of the receptor interplay in developing new antidepressant drugs, the effects of 5HT1AR-FGFR1 complex activation were investigated in hippocampal pyramidal neurons and in midbrain dorsal raphe serotonergic neurons of SD rats and of a genetic rat model of depression (the Flinders Sensitive Line (FSL) rats of SD origin) using an electrophysiological approach. The results showed that in the raphe-hippocampal 5HT system of SD rats, 5HT1AR-FGFR1 heteroreceptor activation by specific agonists reduced the ability of the 5HT1AR protomer to open the GIRK channels through the allosteric inhibitory interplay produced by the activation of the FGFR1 protomer, leading to increased neuronal firing. On the contrary, in FSL rats, FGFR1 agonist-induced inhibitory allosteric action at the 5HT1AR protomer was not able to induce this effect on GIRK channels, except in CA2 neurons where we demonstrated that the functional receptor-receptor interaction is needed for producing the effect on GIRK. In keeping with this evidence, hippocampal plasticity, evaluated as long-term potentiation induction ability in the CA1 field, was impaired by 5HT1AR activation both in SD and in FSL rats, which did not develop after combined 5HT1AR-FGFR1 heterocomplex activation in SD rats. It is therefore proposed that in the genetic FSL model of depression, there is a significant reduction in the allosteric inhibition exerted by the FGFR1 protomer on the 5HT1A protomer-mediated opening of the GIRK channels in the 5HT1AR-FGFR1 heterocomplex located in the raphe-hippocampal serotonin system. This may result in an enhanced inhibition of the dorsal raphe 5HT nerve cell and glutamatergic hippocampal CA1 pyramidal nerve cell firing, which we propose may have a role in depression.

Unveiling behavioral and molecular neuroadaptations related to the antidepressant action of cannabidiol in the unpredictable chronic mild stress model.

Introduction: This study aims to further characterize cannabidiol's pharmacological and molecular profile as an antidepressant. Methods: Effects of cannabidiol (CBD), alone or combined with sertraline (STR), were evaluated in male CD1 mice (n = 48) exposed to an unpredictable chronic mild stress (UCMS) procedure. Once the model was established (4 weeks), mice received CBD (20mg·kg-1, i.p.), STR (10mg·kg-1, p.o.) or its combination for 28days. The efficacy of CBD was evaluated using the light-dark box (LDB), elevated plus maze (EPM), tail suspension (TS), sucrose consumption (SC) and novel object recognition (NOR) tests. Gene expression changes in the serotonin transporter, 5-HT1A and 5-HT2A receptors, BDNF, VGlut1 and PPARdelta, were evaluated in the dorsal raphe, hippocampus (Hipp) and amygdala by real-time PCR. Besides, BDNF, NeuN and caspase-3 immunoreactivity were assessed in the Hipp. Results: CBD exerted anxiolytic and antidepressant-like effects at 4 and 7days of treatment in the LDB and TS tests, respectively. In contrast, STR required 14 days of treatment to show efficacy. CBD improved cognitive impairment and anhedonia more significantly than STR. CBD plus STR showed a similar effect than CBD in the LBD, TST and EPM. However, a worse outcome was observed in the NOR and SI tests. CBD modulates all molecular disturbances induced by UCMS, whereas STR and the combination could not restore 5-HT1A, BDNF and PPARdelta in the Hipp. Discussion: These results pointed out CBD as a potential new antidepressant with faster action and efficiency than STR. Particular attention should be given to the combination of CBD with current SSRI since it appears to produce a negative impact on treatment.

Psilocybin to promote synaptogenesis in the brains of patients with mild cognitive impairment

Amnestic mild cognitive impairment (aMCI) may represent a prodromal stage of Alzheimer's disease dementia (ADD) for which there are no known treatments. There is renewed interest in using psychedelics, including psilocybin, to treat neuropsychiatric disorders. Evidence suggests that psilocybin exerts its psychedelic, and possibly its clinical effects, through 5HT2A serotonin receptor (5HT2A-R) agonism. Intriguingly, reduced 5HT2A-R density in the neocortex is associated with cognitive impairment. Promisingly, the results of preclinical studies suggest psilocybin may promote synaptogenesis in brain regions associated with learning and memory, possibly facilitated by 5HT2A-R agonism. As such, psilocybin is worth exploring as a novel therapeutic for aMCI to counter neurogenerative disease progression. Using a double-blind-placebo controlled design, the proposed positron emission tomography study will assess whether psilocybin increases synaptic density, as measured by the radioligand [18F]SynVesT-1, in the hippocampus and prefrontal cortex of patients with aMCI, and if changes in synaptic vesicular density are associated with improvements in cognition.

Review of the Trace Amine-Associated Receptor 1 (TAAR1) Agonist Ulotaront: Part II—Summary of Initial Clinical Efficacy/Safety Results

AbstractIntroductionUlotaront is a trace amine-associated receptor 1 (TAAR1) agonist with serotonin 5-HT1A agonist activity that has received FDA Breakthrough Therapy Designation for the treatment of schizophrenia. Here we summarize ongoing clinical research characterizing the efficacy and safety of ulotaront as a member of the novel trace amine-associated receptor 1 (TAAR1) agonist class.MethodsSummarized are results from a double-blind, placebo-controlled study to evaluate the efficacy and safety of ulotaront (50 mg or 75 mg) in an acute exacerbation of schizophrenia, and a 6-month, open-label follow-up study. Also summarized are post-hoc analyses evaluating negative symptom efficacy, and key safety and adverse event (AE) outcomes.ResultsIn the short-term study, treatment with ulotaront was associated with significant (p&lt;0.001) endpoint improvement in the PANSS total score (effect size [ES]: 0.45), the CGI-Severity score (ES: 0.52) and the Brief Negative Symptom Scale total score (ES: 0.48). The incidence of any AE was lower on ulotaront versus placebo (45.8% vs. 50.4%), and the number needed to harm (NNH) for individual AEs on ulotaront were all &gt;40. Ulotaront was associated with lower risk for antipsychotic class-related AEs (extrapyramidal symptoms, akathisia, somnolence, nausea/vomiting, increased weight/metabolic labs, prolactinemia). The 6-month study demonstrated further improvement, with a completion rate (67%) that was higher than reported for current dopamine D2 antipsychotics.ConclusionsThe emerging profile of ulotaront is characterized by significant improvement in positive and negative symptoms of schizophrenia. The safety and tolerability profile of ulotaront is markedly different with respect to antipsychotic class-related AEs. The benefit-risk profile of ulotaront, as a member of a novel TAAR1 agonist class, is distinguished from antipsychotics by lack of AEs related to D2 and serotonin 5-HT2A receptor blockade.FundingSunovion Pharmaceuticals, Inc., and Otsuka Pharmaceutical Development &amp; Commercialization, Inc.

Adjunctive Cariprazine in Patients With Major Depressive Disorder: Post Hoc Analysis of Efficacy by Baseline Antidepressant Response

AbstractIntroductionPatients with major depressive disorder (MDD) often have inadequate response to antidepressant treatment (ADT) requiring augmentation with other treatments. Cariprazine is a D3-preferring D3/D2 and serotonin 5-HT1A receptor partial agonist approved to treat schizophrenia and manic, mixed, and depressive episodes of bipolar I disorder. The efficacy of cariprazine as an adjunctive treatment for patients with MDD and inadequate response to ADT alone has been evaluated in phase 2/3 randomized, double-blind, placebo-controlled trials. Post hoc analyses of one phase 3 trial (NCT03738215) evaluated cariprazine + ADT for improving depressive symptoms in subgroups of patients categorized by 1) the level of response to ongoing ADT at baseline and 2) the number of ADTs associated with inadequate response during the current episode.MethodsPatients were randomized to placebo + ADT (n=254), cariprazine 1.5 mg/d + ADT (n=252), or cariprazine 3 mg/d + ADT (n=253) for 6 weeks of double-blind treatment. Post hoc analyses evaluated change from baseline to week 6 in MADRS total score in subgroups of patients who had ≥25%–&lt;50% or &lt;25% response to ongoing ADT at baseline, and in subgroups of patients who had inadequate response to 1 or ≥2 ADTs in the current episode. Analyses used a mixed-effects model for repeated measures; least squares mean differences (LSMD) versus placebo with 95% confidence interval (95% CI) were calculated.ResultsAt baseline, 65.1% (n=486) of patients had an ADT response level between 25%–&lt;50% and 34.9% (n=261) of patients had an ADT response level &lt;25%. Mean MADRS total score reductions were greater for cariprazine 1.5 mg/d + ADT versus placebo + ADT in both ADT response subgroups (25%–&lt;50% ADT response: -14.8 vs -11.9, LSMD [95% CI]=-2.3 [-4.2, -0.3]; &lt;25% response to ADT: (-14.7 vs -11.7, LSMD [95% CI]=-2.6 [-5.5, 0.3]). For cariprazine 3 mg/d + ADT, mean change in MADRS total score was numerically greater versus placebo in both response subgroups (25%–&lt;50% response=-14.2, LSMD [95% CI]=-1.5 [-3.5, 0.4]; &lt;25% response= -12.3, LSMD [95% CI]=-0.74 [-3.6, 2.1]). Approximately 86% (n=644) and 14% (n=105) of patients in this study had inadequate response to 1 ADT or ≥2 ADTs, respectively, during the current episode. The LSMD (95% CI) in MADRS total score change for cariprazine 1.5 mg/d + ADT versus placebo + ADT was -2.3 (-4.1, -0.6) in the subgroup of patients with 1 previous ADT and -3.2 [-7.1, 0.8]) in the subgroup of patients with ≥2 previous ADTs. For cariprazine 3 mg/d + ADT, the LSMD (95% CI) in MADRS total score change versus placebo was -0.7 (-2.5, 1.0) in the 1 previous ADT subgroup and -4.7 (-8.8, -0.6) in the ≥2 previous ADTs subgroup.ConclusionsIn these post hoc analyses, cariprazine + ADT was associated with greater reductions in MADRS total score versus placebo regardless of the level of response to ongoing ADT at baseline or number of prior ADT failures in the current episode.FundingAbbVie

Categorical Improvement in Depressive Symptom Severity: Results From a Randomized Controlled Trial of Cariprazine for Adjunctive Treatment of MDD

AbstractBackgroundPatients with major depressive disorder (MDD) often do not respond to antidepressant (ADT) monotherapy alone and may require adjunctive treatment to provide adequate symptom relief. Cariprazine (CAR) is a dopamine D3-preferring D3/D2 and serotonin 5-HT1A receptor partial agonist approved to treat adults with schizophrenia and manic, mixed, or depressive episodes of bipolar I disorder. Post hoc analysis of data from a randomized controlled trial evaluated clinically relevant improvements in depressive symptom severity with adjunctive cariprazine in patients with MDD and inadequate response to ADT monotherapy.MethodsPost hoc analysis evaluated data from a randomized, double-blind, placebo-controlled MDD trial (NCT03738215) in patients treated with CAR (1.5 mg/d or 3 mg/d) + ADT or placebo + ADT; the primary outcome was change from baseline to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Post hoc analysis evaluated category shifts from baseline to week 6 in MADRS severity (normal &lt;6, mild 7–19, moderate 20–34, severe ≥35). MADRS severity shifts were reported as the percentage of patients with no change or worsened severity, 1 category improvement, ≥1 category improvement, and ≥2 category improvement. Examples of categorical shifts in depressive symptoms at week 6 include change from severe at baseline to moderate (1 category improvement) and change from severe at baseline to mild (2 category improvement).ResultsOf the 751 patients in the intent-to-treat (ITT) population (CAR: 1.5 mg/d=250, 3.0 mg/d=252; placebo=249), baseline MADRS severity was mild in 1.5%, moderate in 64%, and severe in 35%. Fewer CAR + ADT patients compared to placebo + ADT had no change or worsened MADRS severity at week 6 (CAR: 1.5 mg/d=32%, 3.0 mg/d=33%; placebo=42%). Approximately 68% of patients treated with CAR + ADT demonstrated a MADRS severity improvement of 1 category or greater by week 6 (CAR: 1.5 mg/d=68%, 3.0 mg/d=67%; placebo=58%). A greater percentage of patients in the CAR 1.5 mg/d group also had a 2 or greater category improvement versus CAR 3.0 mg/d or placebo 6 (CAR: 1.5 mg/d=28%, 3.0 mg/d=17%; placebo=19%).ConclusionsIn this post hoc analysis, CAR + ADT was associated with a greater proportion of patients with improvements in depressive symptom severity categories compared with placebo + ADT. These results may suggest that CAR + ADT is associated with clinically meaningful depressive symptom improvement in MDD patients.FundingAbbVie

Cariprazine for the Adjunctive Treatment of Major Depressive Disorder: Results of a Randomized Phase 3 Placebo-Controlled Study (Study 301)

AbstractBackgroundPatients with major depressive disorder (MDD) often do not respond to antidepressant (ADT) monotherapy; adjunctive treatment is often used to address this unmet need. Cariprazine (CAR), a dopamine D3-preferring D3/D2 and serotonin 5-HT1A receptor partial agonist approved to treat adults with manic, mixed, or depressive episodes of bipolar I disorder, is under investigation as adjunctive therapy for patients with MDD.MethodsThis randomized, double-blind, phase 3 placebo (PBO)-controlled study assessed the efficacy, safety, and tolerability of CAR 1.5 and 3 mg/d as an adjunct to ADT in adult patients with MDD (18–65 years) and inadequate response to ADT alone (NCT03738215). The primary endpoint was change from baseline to week 6 in Montgomery-Åsberg Depression Rating Scale (MADRS) total score. Hamilton Depression Rating Scale (HAMD-17), Hamilton Anxiety Rating Scale (HAM-A), and Clinical Global Impressions (CGI) were also assessed. Treatment response was defined as at least 50% decrease in MADRS total score at week 6.ResultsPatients (n=751) in the modified intent-to-treat population were randomly assigned to CAR 1.5 mg/d+ADT (n=250), CAR 3 mg/d+ADT (n=252), or PBO+ADT (n=249). Mean age was 44.8 years and 73.4% were female; mean baseline total scores were: MADRS=32.5, HAMD-17=25.9, HAM-A= 21.4. Overall, 89.7% of patients completed the study; rates of discontinuation due to adverse events (AEs) and lack of efficacy were 3.6% and 0.5%, respectively. The difference in MADRS total score change from baseline to week 6 was statistically significant after multiplicity adjustment for CAR 1.5 mg/d vs PBO (-14.1 vs -11.5; adjusted P=.0050), but not for CAR 3 mg/d (-13.1; P=.0727). Differences for CAR 1.5 mg/d vs PBO were observed by week 2 (nominal P=.0453) and maintained at weeks 4 (nominal P&lt;.0001) and 6 (nominal P=.0025). At week 6, more CAR 1.5 mg/d patients (44%) than PBO patients (34.9%) responded to treatment (nominal P=.0446). Greater improvement in the CGI-I scores was observed for CAR 1.5 (nominal P=.0026) and 3 mg/d (nominal P=.0076) vs PBO. At week 6, improvement in HAMD-17 total score reached nominal significance for CAR 1.5 mg/d vs PBO (-13.1 vs -11.1; nominal P=.0017), but not for CAR 3 mg/day (-12.2; P=.0783). HAM-A improvement was greater for CAR 1.5 mg/d vs PBO (nominal P=.0370). There were no deaths; 2 serious AEs occurred in each group (CAR: kidney infection, social stay hospitalization; PBO: depression, multiple sclerosis). The most common CAR AEs (≥5% and twice PBO) were akathisia and nausea.ConclusionCariprazine 1.5 mg/d was effective as adjunctive treatment in adults with MDD and inadequate response to ADT. Cariprazine was generally well tolerated, with a safety profile that was consistent with other indications. Together with results from a prior flex-dose study, these results suggest that adjunctive cariprazine may be an effective option for patients with inadequate response to ADT alone.FundingAbbVie

Expression of the serotonergic system components in the placenta in various types of preeclampsia

BACKGROUND: The serotonergic system plays an important role in the formation and development of the feto-placental complex. The study of the expression of the serotonin system components, including placental 5-HT2A (serotonin receptor) and SERT (serotonin transporter), in preeclampsia will create prerequisites for discovering new ways to correct hypertensive pregnancy complications and methods of influencing pregnancy outcomes.&#x0D; AIM: The aim of this study was to compare the expressions of 5-HT2A and SERT in placental tissue in pure preeclampsia and its combinations with other complications of pregnancy.&#x0D; MATERIALS AND METHODS: A comparative cohort study was conducted among patients with different preeclampsia phenotypes: preeclampsia (n = 6), preeclampsia and gestational diabetes mellitus (n = 6), gestational diabetes mellitus and superimposed preeclampsia (preeclampsia + chronic arterial hypertension) (n = 6), and normal pregnancy without pregnancy complications (n = 6). The expression of 5-HT2A (Abcam, USA) and SERT (BiossAntibodies, USA) was studied in placenta samples from all study groups by immunohistochemical method. Morphometric analysis was performed using the VideoTest-Morphology 5.2 program (Videotest Ltd., Russia). The database was constructed and statistical processing was performed using Microsoft Excel 2007 (Microsoft Corporation, USA) and the StatTech program v. 2.6.4 (Stattech Ltd., Russia).&#x0D; RESULTS: The expression of SERT and 5-HT2A is higher in the studied pregnancy complications when compared to the normal one. The relative 5-HT2A expression area in the placenta among the studied nosologies is higher in preeclampsia without gestational diabetes mellitus or in superimposed preeclampsia in combination with chronic arterial hypertension compared to expression in placentas in preeclampsia in combination with gestational diabetes mellitus or in preeclampsia in combination with gestational diabetes mellitus and chronic arterial hypertension (p = 0.02 and p = 0.017, respectively). The relative area of SERT expression is higher in preeclampsia without gestational diabetes mellitus or chronic arterial hypertension and in preeclampsia in combination with gestational diabetes mellitus compared to preeclampsia in combination with gestational diabetes mellitus and chronic arterial hypertension (p = 0.002 and p = 0.012, respectively).&#x0D; CONCLUSIONS: The highest expressions of 5-HT2A and SERT among the studied preeclampsia phenotypes were found in placentas in preeclampsia without gestational diabetes mellitus or chronic arterial hypertension.

Pharmacological evaluation of the anxiolytic-like effects of an aqueous extract of the Raphanus sativus L. sprouts in mice

Raphanus sativus L. (Brassicaceae), commonly known as radish, is consumed worldwide as a vegetable. However, its benefits on mental health are unknown. The aim of this study was to evaluate its anxiolytic-like effects and safety using different experimental models. An aqueous extract of R. sativus sprouts (AERSS) was pharmacologically evaluated by intraperitoneal route (i.p.) at 10, 30, and 100 mg/kg and orally (p.o.) at 500 mg/kg on behavior by using open-field and plus-maze tests. In addition, its acute toxicity (LD50) was determined by the Lorke's method. Diazepam (1 mg/kg, i.p.) and buspirone (4 mg/kg, i.p.) were the reference drugs. A significant and anxiolytic-like dosage of AERSS (30 mg/kg, i.p.) resembling the effects of reference drugs was chosen to explore the involvement of GABAA/BDZs site (flumazenil, 5 mg/kg, i.p.) and serotonin 5-HT1A receptors (WAY100635, 1 mg/kg, i.p.) as a possible mechanism of action. A 500 mg/kg, p.o. dosage of AERSS produced an anxiolytic-like response equivalent to 100 mg/kg, i.p. No acute toxicity was observed since a LD50 > 2000 mg/kg, i.p. The phytochemical analysis allowed the identification and quantification of major presence of sulforaphene (2500 µM), sulforaphane (15 µM), iberin (0.75 µM), and indol-3-carbinol (0.75 µM), as major constituents. Both the GABAA/BDZs site and serotonin 5-HT1A receptors were involved in the anxiolytic-like activity of AERSS, depending on the pharmacological parameter or the experimental assay tested. Our results demonstrate that the anxiolytic activity of R. sativus sprouts involves GABAA/BDZs site and serotonin 5-HT1A receptors supporting its health benefits in the treatment of anxiety beyond the satisfaction of basic nutritional needs.

Cannabidiol improves haloperidol-induced motor dysfunction in zebrafish: a comparative study with a dopamine activating drug

BackgroundCannabidiol (CBD) extracted from the cannabis plant is believed to have a medicinal value due to its neuroprotective effect via anti-inflammatory and antioxidant action. Recent behavioral studies in rats have reported that CBD mediates serotonin (5-HT1A) receptor action to improve motor dysfunction induced by dopamine (D2) receptor blockade. In particular, its effect on D2 receptor blockade in the striatum is an important function associated with neurological disorders resulting from various extrapyramidal motor dysfunctions. Dopaminergic neurodegeneration associated with this site is known for inducing Parkinson’s disease (PD), which often affects the elderly. It is also known to cause drug-induced Parkinsonism. This study examines the ameliorating effect of CBD, which does not act directly on D2 receptors, against drug-induced motor dysfunction induced by the antipsychotic drug (haloperidol).MethodsWe created a drug-induced Parkinsonism model in zebrafish larvae using an antipsychotic drug (haloperidol). We evaluated the distance traveled and repetitive light-stimulation response. Furthermore, we examined whether administration of several concentrations of CBD ameliorates symptoms of the Parkinsonism model and compared its effects with those of antiparkinsonian drug ropinirole.ResultsCBD concentrations equal to half of haloperidol’s resulted in an almost complete reversal of haloperidol-induced motor dysfunction, as measured by the distance traveled by the zebrafish and their response to light-stimulus. While ropinirole also significantly reversed haloperidol’s effects at the same concentration as CBD, CBD was more effective than ropinirole.ConclusionsCBD-induced motor dysfunction improvement via D2 receptor blockade is a potential novel mechanism for the treatment of haloperidol-induced motor dysfunction.

Use of cariprazine as an impulsivity regulator in an adolescent with non suicidal self-injury and suicidal attempts. Case report

IntroductionAdolescents with emotional dysregulation are at risk for self-injury. Antipsychotics are often used to manage these symptoms.ObjectivesThe aim of the present case is to show the use of cariprazine as an effective drug for emotional dysregulation and impulsivity in a 17-year-old adolescent girlMethodsCase reportResultsThe patient was a 17-year-old female admitted to in patient psychiatric unit for a self-harm attempt due to sertraline overdose. She was being followed up for self-injury, anxiety and eating disorder symptoms. Her treatment was sertraline 200 mg, diazepam 20 mg per day and olanzapine 15 mg per day. With this medication she had gained up to 7 kgs in 4 months. A progressive change was made with cariprazine up to 3 mg and olanzapine was reduced to 2.5 mg at night. With this adjustment the patient did not present worsening in anxiety levels, with adequate impulse control and being able to perform emotional regulation strategies.ConclusionsAlthough it has no indication in patients under 18 years of age, it shows a case of good tolerance and efficacy for the management of impulsivity by improving emotional regulation. Cariprazine is an atypical antipsychotic that works through partial agonism on dopaminergic receptors, serotonin 5-HT1A receptors and an antagonist at the 5-HT2B receptors, with moderate affinity for adrenergic, histaminergic, and cholinergic receptors reducing the likelihood of side effectsDisclosure of InterestNone Declared

Pimavanserin and trazodone combination in behavioral disorders in severe dementia with Lewy bodies

Dementia with Lewy bodies (DLB) is characterized by neurocognitive disorders associated with core clinical features including hallucinations. There is currently no cure but a combination of symptomatic treatments: clozapine is commonly used in DLB-related psychosis. Pimavanserin is a serotonin5HT-2A receptor inverse agonist that has recently been shown to reduce psychosis related to dementia. Trazodone is a serotonin reuptake inhibitor and a 5-HT2 receptor antagonist: it is effective in the treatment of the frontal syndrome and is commonly used in frontotemporal degeneration. We describe three patients with DLB, hospitalized in the cognitive-behavioral unit of the University Hospitals of Strasbourg, who presented with major visual hallucinations, delusion, and an orbitofrontal syndrome including disinhibition, agitation, and irritability. The 3 patients were intolerant of low-dose Clozapine (neutropenia for one, somnolence for the other and Pisa syndrome and falls for the last one). We evaluated the Neuropsychiatric Inventory (NPI) before and after the introduction of both treatments. Given their psychotic and frontal symptoms, we used Pimavanserin and Trazodone simultaneously. After 4 to 6 weeks of treatment, a marked improvement was observed in all 3 patients, with a decrease of the NPI scores from a mean of 88 to 38. To our knowledge, there is no previously described combination of these two treatments in DLB. A clinical trial combining these two molecules against pervasive behavioral disorders in DLB would be interesting in view of these preliminary results.

Off-target activity of NBOMes and NBOMe analogs at the µ opioid receptor.

New psychoactive substances (NPS) are introduced on the illicit drug market at a rapid pace. Their molecular targets are often inadequately elucidated, which contributes to the delayed characterization of their pharmacological effects. Inspired by earlier findings, this study set out to investigate the µ opioid receptor (MOR) activation potential of a large set of psychedelics, substances which typically activate the serotonin (5-HT2A) receptor as their target receptor. We observed that some substances carrying the N-benzyl phenethylamine (NBOMe) structure activated MOR, as confirmed by both the NanoBiT® βarr2 recruitment assay and the G protein-based AequoScreen® Ca2+ release assay. The use of two orthogonal systems proved beneficial as some aspecific, receptor independent effects were found for various analogs when using the Ca2+ release assay. The specific 'off-target' effects at MOR could be blocked by the opioid antagonist naloxone, suggesting that these NBOMes occupy the same common opioid binding pocket as conventional opioids. This was corroborated by molecular docking, which revealed the plausibility of multiple interactions of 25I-NBOMe with MOR, similar to those observed for opioids. Additionally, structure-activity relationship findings seen in vitro were rationalized in silico for two 25I-NBOMe isomers. Overall, as MOR activity of these psychedelics was only noticed at high concentrations, we consider it unlikely that for the tested compounds there will be a relevant opioid toxicity in vivo at physiologically relevant concentrations. However, small modifications to the original NBOMe structure may result in a panel of more efficacious and potent MOR agonists, potentially exhibiting a dual MOR/5-HT2A activation potential.