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Rationale: Weight gain is a frequent side effect of treatment with SGAs (second-generation antipsychotics) and a leading cause for nonadherence. Several candidate genes have been identified that could influence the amount of AIWG (antipsychotic-induced weight gain). The polymorphism rs17782313 near the MC4R (human melanocortin 4 receptor gene) was strongly associated with obesity in a large scale GWAS (genome wide association study), yet previous studies investigating its impact on AIWG did not lead to a definite conclusion regarding its effect. In particular, they were all relatively short and had a naturalistic design. Objective: We therefore examined the influence of the rs17782313 polymorphism on SGA-related weight gain. Methods: Participants of a multicenter randomized, controlled, double-blind study comparing two treatment strategies in individuals with schizophrenia or schizoaffective disorder were genotyped using a rapid-cycle polymerase chain reaction. Up to 252 individuals completed the first 2 weeks (phase I), 212 the entire 8 weeks (hence 'completers'). Patients received either amisulpride or olanzapine or both consecutively. Thirty-seven had their first episode. Weight gain occurring in different genotypes was statistically compared and confounding factors were adjusted by stepwise multiple linear regression. A correction for multiple testing was included. Results: Within 212 'completers', carriers of the C allele had a higher absolute weight gain than those homozygous for the T allele (2.6 kg vs. 1.2 kg), though this observation was not significant (P = 0.063). In the amisulpride subpopulation, this association appeared stronger and reached significance (2.5 kg vs. 0.7 kg, P = 0.043), though failed to remain significant after correction for multiple testing. A stepwise multiple linear regression showed a significant association in both the whole study population (P < 0.001) and the amisulpride subpopulation (P < 0.001). Conclusion: Our results indicate that the rs17782313 polymorphism might influence antipsychotic-induced weight gain and therefore confirm some of the earlier conclusions. [ABSTRACT FROM AUTHOR]

Rationale: Inadequate responses to current schizophrenia treatments have accelerated research into novel therapeutic approaches. Objectives: This study investigated the efficacy and tolerability of adjunctive L-theanine, an ingredient with neuroimmunomodulatory and neuroprotective properties, for chronic schizophrenia. Methods: Eighty chronic schizophrenia inpatients were equally assigned to receive risperidone (6 mg/day) plus either L-theanine (400 mg/day) or matched placebo in this 8-week, randomized, parallel-group, double-blind, placebo-controlled trial. The participants were assessed using the Positive and Negative Syndrome Scale (PANSS) by recording the results of subscales at baseline and weeks 4 and 8 to measure treatment efficacy. Additionally, the participants were assessed for the Hamilton Depression Rating Scale (HDRS) and adverse events, including the Extrapyramidal Symptom Rating Scale (ESRS). Results: Sixty patients, 30 in each group, were included in the analyses. All baseline demographic and clinical characteristics were comparable between the groups (p-values > 0.05). The reduction rates from baseline to endpoint in negative, general psychopathology, and total scores of PANSS were greater in the L-theanine group (p-values = 0.03, 0.01, and 0.04, respectively). Regarding general psychopathology scores, the reduction in the L-theanine group was also greater until week 4 (p-value < 0.01). The time × treatment interaction effect was significant on negative (p-value = 0.03), general psychopathology (p-value < 0.01), and total (p-value = 0.04) scores of PANSS, indicating additional improvements in the L-theanine group. The HDRS and side effects were comparable between the groups (p-values > 0.05). Conclusions: L-Theanine adjunct to risperidone safely and tolerably outperformed adjunctive placebo for schizophrenia, and promising evidence indicated its effects on primary negative symptoms, which need to be scrutinized in further studies. Trial registration: The study protocol was registered and published prospectively in the Iranian Registry of Clinical Trials (http://www.irct.ir; registration number: IRCT20090117001556N133) on 2020–12-12. [ABSTRACT FROM AUTHOR]

Rationale : While meta-analyses of clinical trials found that lurasidone and partial dopamine agonists (brexpiprazole and aripiprazole) were the antipsychotics less likely to cause QTc prolongation, and sertindole, amisulpride, and ziprasidone were the most frequently associated with this adverse drug reaction; no real-world studies have investigated this risk between the different antipsychotics. Objectives and methods: Using data recorded from 1967 to 2019 in VigiBase®, the World Health Organization's Global Individual Case Safety Reports database, we performed disproportionality analysis to investigate the risk of reporting QT prolongation between 20 antipsychotics. Results: Sertindole had the highest risk of reporting QT prolongation, followed by ziprasidone and amisulpride. Lurasidone was associated with the lowest risk. First-generation antipsychotics were associated with a greater QT prolongation reporting risk (ROR, 1.21; 95%CI, 1.10–1.33) than second-generation antipsychotics. A positive correlation was found between the risk of reporting QT prolongation and affinity for hERG channel (R2 = 0.14, slope = Pearson coefficient = 0.41, p value = 0.1945). Conclusions: This large study in a real-world setting suggests that sertindole and ziprasidone were the antipsychotics drugs associated with the highest risk of QT prolongation reporting. Our results suggest that lurasidone is less associated with QT interval prolongation reports. Our study also suggests that antipsychotics with the higher hERG affinity are more associated with to QT prolongations reports. [ABSTRACT FROM AUTHOR]

LB-102 is an N-methylated analogue of amisulpride under development to treat schizophrenia. LB-102 was evaluated in a Phase 1, double-blind, placebo-controlled, clinical study to evaluate safety and pharmacokinetics. This was a first-in-human study examining single and multiple doses of LB-102 administered orally in 64 healthy volunteers. Dosing in the single ascending dose (SAD) portion of the study was initially planned to be 50, 100, 200, and 400 mg, with doses in the multiple ascending dose (MAD) portion to be determined based on observations in the SAD portion. As a result of two cases of EPS (acute dystonia) at 200 mg in the MAD portion of the study, dosing of that arm was discontinued and doses for the remaining cohort were decreased to 150 mg/day. Dose escalation was guided by safety and plasma concentrations of LB-102 compared to a translational model. LB-102 was generally safe and well-tolerated, and clinical lab values were unremarkable at all doses, save for prolactin which was transiently elevated in the majority of subjects treated with LB-102; there were no clinical observations associated with the increases in prolactin elevation. There was evidence of transient QT interval prolongation at the 200 mg dose, none of which resulted in clinical observation or triggered stopping criteria. There were four instances of EPS (acute dystonia), typically associated with dopamine receptor occupancy in excess of 80%, one at 100 mg QD, one at 75 mg BID, and two at 100 mg BID. A phase 2 clinical study of LB-102 in schizophrenia patients with PANSS as primary endpoint is being planned. [ABSTRACT FROM AUTHOR]

Rationale: The precise diagnosis and treatment of cognitive impairment remains a major challenge in the field of schizophrenia (SCZ) research. Synaptic dysfunction and loss are thought to be closely related to the occurrence and development of SCZ and may be involved in cognitive dysfunction. Objectives: The purpose of this study was to investigate whether neuronal pentraxins (NPTXs) plays a role in the etiology of SCZ and provide evidence of its possible therapeutic value a new target for drug development. Methods: We recruited 275 participants, of whom 148 were SCZ from psychiatric hospital and 127 healthy control (HC) subjects from communities. Plasma concentrations of NPTXs were measured in HC and SCZ at baseline and after 8 weeks of antipsychotic treatment. The MATRICS Cognitive Consensus Battery was used to evaluate cognitive function. Furthermore, the brain is parcellated into 246 subregions using the Brainnetome atlas, and we extracted regional white matter volumes from magnetic resonance images of the SCZ groups. Results: Plasma NPTX2 levels were significantly lower in SCZ compared with HC subjects, but were significantly raised in SCZ after 8 weeks of antipsychotic treatment compared to baseline. In addition, baseline plasma NPTX2 levels were positively correlated with cognitive performance. Conclusions: These findings indicate that NPTX2 may reveal novel aspects of disease etiology and act as a promising target for new drug development. [ABSTRACT FROM AUTHOR]

Rationale: Clozapine is a unique medication with a potential role in the treatment of severe borderline personality disorder (BPD). Objectives: The review examines the effectiveness of clozapine as a medication for management for severe BPD with high risk of suicide, violence or imprisonment, and aims to help guide clinical practice in managing severe BPD. Methods: A database search of the terms "Clozapine" AND "BPD"; "Antipsychotics" AND "BPD"; "Clozapine" AND "Borderline Personality Disorder"; and "Antipsychotics" AND "Borderline Personality Disorder" were performed in CINAHL, Cochrane Library, Embase, Medline, PsychINFO, PubMed, and Web of Science. Full-text articles of clinical clozapine use for BPD were included for review. Results: A total of 24 articles consisting of 1 randomised control trial, 10 non-controlled trials, and 13 case reports were identified. Most of the studies reported benefits from clozapine when used for severe BPD. Many of the studies focused on clozapine use in BPD patients at high risk of suicide. Results from these non-controlled and case reports support the use of clozapine in patients with severe BPD at high risk of suicide. Conclusion: There may be a role for clozapine in treating severe treatment refractory BPD, especially for those patients at high risk of suicide and frequent hospitalisations. [ABSTRACT FROM AUTHOR]

Rationale: We have discovered that rats at the age of 18 months begin to twitch their heads spontaneously (spontaneous head twitching, SHT). To date, no one has described this phenomenon. Objectives: The purpose of this study was to characterize SHT pharmacologically and to assess some possible mechanisms underlying SHT. Methods: Wistar male rats were used in the study. Animals at the age of 18 months were qualified as HSHT (SHT ≥ 7/10 min observations) or LSHT (SHT < 7/10 min observations). Quantitative real-time PCR with TaqMan low-density array (TLDA) approach was adopted to assess the mRNA expression of selected genes in rat's hippocampus. Results: HSHT rats did not differ from LSHT rats in terms of survival time, general health and behavior, water intake, and spontaneous locomotor activity. 2,5-dimethoxy-4-iodoamphetamine (DOI) at a dose of 2.5 mg/kg increased the SHT in HSHT and LSHT rats, while ketanserin dose-dependently abolished the SHT in the HSHT rats. The SHT was reduced or abolished by olanzapine, clozapine, risperidone, and pimavanserin. All these drugs have strong 5-HT2A receptor–inhibiting properties. Haloperidol and amisulpride, as antipsychotic drugs with a mostly dopaminergic mechanism of action, did not influence SHT. Similarly, escitalopram did not affect SHT. An in-depth gene expression analysis did not reveal significant differences between the HSHT and the LSHT rats. Conclusions: SHT appears in some aging rats (about 50%) and is permanent over time and specific to individuals. The 5-HT2A receptor strongly controls SHT. HSHT animals can be a useful animal model for studying 5-HT2A receptor ligands. [ABSTRACT FROM AUTHOR]

Sex-biased differences in schizophrenia are evident in several features of the disease, including symptomatology and response to pharmacological treatments. As a neurodevelopmental disorder, these differences might originate early in life and emerge later during adolescence. Considering that the disruption of the glutamatergic system during development is known to contribute to schizophrenia, we hypothesized that the neonatal phencyclidine model could induce sex-dependent behavioral and neurochemical changes associated with this disorder during adolescence. C57BL/6 mice received either saline or phencyclidine (5, 10, or 20 mg/kg) on postnatal days (PN) 7, 9, and 11. Behavioral assessment occurred in late adolescence (PN48-50), when mice were submitted to the open field, social interaction, and prepulse inhibition tests. Either olanzapine or saline was administered before each test. The NMDAR obligatory GluN1 subunit and the postsynaptic density protein 95 (PSD-95) were evaluated in the frontal cortex and hippocampus at early (PN30) and late (PN50) adolescence. Neonatal phencyclidine evoked dose-dependent deficits in all analyzed behaviors and males were more susceptible. Males also had reduced GluN1 expression in the frontal cortex at PN30. There were late-emergent effects at PN50. Cortical GluN1 was increased in both sexes, while phencyclidine increased cortical and decreased hippocampal PSD-95 in females. Olanzapine failed to mitigate most phencyclidine-evoked alterations. In some instances, this antipsychotic aggravated the deficits or potentiated subthreshold effects. These results lend support to the use of neonatal phencyclidine as a sex-biased neurodevelopmental preclinical model of schizophrenia. Olanzapine null effects and deleterious outcomes suggest that its use during adolescence should be further evaluated. [ABSTRACT FROM AUTHOR]

Presents a study which evaluated the relationship between prolactin plasma concentration and central (striatum,temporal cortex and thalamus) D2/D3 receptor occupancy in amisulpride treated schizophrenic patients. Methods; Results; Conclusions.

Amisulpride is approved for clinical use in treating schizophrenia in a number of European countries and also for treating dysthymia, a mild form of depression, in Italy. Amisulpride has also been demonstrated to be an antidepressant for patients with major depression in many clinical trials. In part because of the selective D2/D3 receptor antagonist properties of amisulpride, it has long been widely assumed that dopaminergic modulation is the proximal event responsible for mediating its antidepressant and antipsychotic properties. The purpose of these studies was to determine if amisulpride’s antidepressant actions are mediated by off-target interactions with other receptors. We performed experiments that: (1) examined the pharmacological profile of amisulpride at a large number of central nervous system (CNS) molecular targets and, (2) after finding high potency antagonist affinity for human 5-HT7a serotonin receptors, characterized the actions of amisulpride as an antidepressant in wild-type and 5-HT7 receptor knockout mice. We discovered that amisulpride was a potent competitive antagonist at 5-HT7a receptors and that interactions with no other molecular target investigated in this paper could explain its antidepressant actions in vivo . Significantly, and in contrast to their wild-type littermates, 5-HT7 receptor knockout mice did not respond to amisulpride in two widely used rodent models of depression, the tail suspension test and the forced swim test. These results indicate that 5-HT7a receptor antagonism, and not D2/D3 receptor antagonism, likely underlies the antidepressant actions of amisulpride. [ABSTRACT FROM AUTHOR]

Reports on a study which investigated the occupancy of atypical antipsychotic drugs, amisulpride and risperidone, would preferentially occupy of D2/D3 dopamine receptors in limbic and associative regions of the striatum. Methods used in the study; Occupancy values for head of caudate and putamen.

Abstract The benzamide amisulpride (ASP) is a selective D[sub 2]-like dopamine antagonist, while flupentixol (FPX), a thioxanthene, blocks D[sub 2]-like, D[sub 1]-like and 5-HT[sub 2] receptors. To evaluate efficacy and safety of ASP and to investigate the importance of an additional D[sub 1]-like antagonism for antipsychotic effects and extrapyramidal tolerability, a randomized double-blind multi-center study versus FPX as reference drug was performed for 6 weeks in 132 patients suffering from acute schizophrenia (DSM-III-R) with predominant positive symptomatology. Doses were initially fixed (ASP: 1000 mg/day; FPX: 25 mg/day) but could be reduced by 40% in case of side effects (mean daily doses: ASP: 956 mg; FPX: 22.6 mg). Intention-to-treat evaluation demonstrated significant improvement under both medications. The difference between the mean BPRS decreases of both treatment groups was 5.6 points (95% CI: 0.55; 10.65) in favour of ASP. According to CGI, 62% of patients in either drug group were treatment responders. ANCOVA analysis showed that reductions of BPRS (ASP: -42%; FPX: -32%) and SAPS (ASP: -78 %; FPX: -65%) were more pronounced under ASP. Due to adverse events, significantly fewer ASP patients (6%) were withdrawn from the study (FPX: 18%). Extrapyramidal tolerability was better in the ASP group, as demonstrated by smaller increases in the Simpson-Angus Scale, the AIMS, and the Barnes Akathisia Scale in ANCOVA analyses with dosage as covariate. ASP appears to be as effective as FPX with regard to antipsychotic effects on positive schizophrenic symptomatology, while extrapyramidal tolerability is better. These conclusions have to... [ABSTRACT FROM AUTHOR]

Neuropsychiatric disorders are multifactorial disturbances that encompass several hypotheses, including changes in neurodevelopment. It is known that brain development disturbances during early life can predict psychosis in adulthood. As we have previously demonstrated, rotenone, a mitochondrial complex I inhibitor, could induce psychiatric-like behavior in 60-day-old rats after intraperitoneal injections from the 5th to the 11th postnatal day. Because mitochondrial deregulation is related to psychiatric disorders and the establishment of animal models is a high-value preclinical tool, we investigated the responsiveness of the rotenone (Rot)-treated newborn rats to pharmacological agents used in clinical practice, haloperidol (Hal), and methylphenidate (MPD). Taken together, our data show that Rot-treated animals exhibit hyperlocomotion, decreased social interaction, and diminished contextual fear conditioning response at P60, consistent with positive, negative, and cognitive deficits of schizophrenia (SZ), respectively, that were reverted by Hal, but not MPD. Rot-treated rodents also display a prodromal-related phenotype at P35. Overall, our results seem to present a new SZ animal model as a consequence of mitochondrial inhibition during a critical neurodevelopmental period. Therefore, our study is crucial not only to elucidate the relevance of mitochondrial function in the etiology of SZ but also to fulfill the need for new and trustworthy experimentation models and, likewise, provide possibilities to new therapeutic avenues for this burdensome disorder. [ABSTRACT FROM AUTHOR]

Rationale: Schizophrenia is a mental illness which is characterised by positive and negative symptoms and by cognitive impairments. While the major prevailing hypothesis is that altered dopaminergic and/or glutamatergic transmission contributes to this disease, there is evidence that the noradrenergic system also plays a role in its major symptoms. Objectives: In the present paper, we investigated the pro-cognitive effect of 1-methyl-1,2,3,4-tetrahydroisoquinoline (1MeTIQ) an endogenous neuroprotective compound, on ketamine-modelled schizophrenia in rats. Methods: We used an antagonist of NMDA receptors (ketamine) to model memory deficit symptoms in rats. Using the novel object recognition (NOR) test, we investigated the pro-cognitive effect of 1MeTIQ. Additionally, olanzapine, an atypical antipsychotic drug, was used as a standard to compare the pro-cognitive effects of the substances. In vivo microdialysis studies allowed us to verify the changes in the release of monoamines and their metabolites in the rat striatum. Results: Our study demonstrated that 1MeTIQ, similarly to olanzapine, exhibits a pro-cognitive effect in NOR test and enhances memory disturbed by ketamine treatment. Additionally, in vivo microdialysis studies have shown that ketamine powerfully increased noradrenaline release in the rat striatum, while 1MeTIQ and olanzapine completely antagonised this neurochemical effect. Conclusions: 1MeTIQ, as a possible pro-cognitive drug, in contrast to olanzapine, expresses beneficial neuroprotective activity in the brain, increasing concentration of the extraneuronal dopamine metabolite, 3-methoxytyramine (3-MT), which plays an important physiological role in the brain as an inhibitory regulator of catecholaminergic activity. Moreover, we first demonstrated the essential role of noradrenaline release in memory disturbances observed in the ketamine-model of schizophrenia, and its possible participation in negative symptoms of the schizophrenia. [ABSTRACT FROM AUTHOR]

Background: People with schizophrenia frequently have cognitive dysfunction, which does not respond to pharmacological interventions. Varenicline has been identified as a potential treatment option for nicotinic receptor dysfunction with a potential to treat cognitive impairment in schizophrenia. Methods: We conducted a systematic review of Pubmed, Embase, Psycinfo, CINAHL and the Cochrane Schizophrenia Trial Registry for randomised controlled trials of varenicline in people with schizophrenia for cognitive dysfunction. We excluded trials among people with dementia. We then undertook a meta-analysis with the primary outcome of difference in change of cognitive measures between varenicline and placebo as well as secondary outcomes of difference in rates of adverse events. We conducted a sensitivity analysis on smoking status and study duration. Results: We included four papers in the meta-analysis (n = 339). Varenicline was not superior to placebo for overall cognition (SMD = −0.022, 95% CI −0.154–0.110; Z = −0.333; p = 0.739), attention (SMD = −0.047, 95% CI −0.199–0.104; Z = −0.613; p = 0.540), executive function (SMD = −0.060, 95% CI −0.469–0.348; Z =− 0.290; p = 0.772) or processing speed (SMD = 0.038, 95% CI −0.232–0.308; Z = 0.279; p = 0.780). There was no difference in psychotic symptoms, but varenicline was associated with higher rates of nausea. Sensitivity analyses for smoking status and study duration did not alter the results. Conclusion: Within the present literature, varenicline does not appear to be a useful target compound for improving cognitive impairment in schizophrenia. Based on these results, a trial would need over 2500 participants to be powered to show statistically significant findings. [ABSTRACT FROM AUTHOR]

Rationale: There are many psychotropic drugs available for treatment of schizophrenia. The clinician's choice of the most effective first-line antipsychotic treatment for patients with schizophrenia should balance considerations of differential efficacy of antipsychotics against the relative risk of different side effects., Method: We reviewed recent studies using meta-analytic techniques and additional studies of new antipsychotics which quantitatively evaluate the efficacy of side effects of first- and second-generation antipsychotics and studies of the efficacy on add-on secondary medications. We present an integrated summary of these results to guide a clinician's decision-making., Results: Recent meta-analyses have suggested that antipsychotics are not equivalent in efficacy. Clozapine (effect size [SMD] 0.88 vs. placebo), amisulpride (effect size 0.6 vs placebo), olanzapine (effect size 0.59 vs. placebo), and risperidone (effect size 0.56 vs placebo) show small but statistically significant differences compared to a number of other antipsychotics on measures of overall efficacy (effect sizes 0.33-0.50). However, increasing placebo response remains a concern in interpreting these data. Amisulpride (effect size 0.47 vs placebo) and cariprazine (effect size in one trial compared to risperidone 0.29) have the strongest evidence indicating greater efficacy for treating primary negative symptoms relative to other antipsychotics. In terms of side effects, clozapine and olanzapine have among the highest weight gain potential and sertindole and amisulpride have more effects on QTc prolongation than other commonly used antipsychotics. Prolactin elevation is highest with paliperidone, risperidone, and amisulpride. Adjunctive treatment with an antidepressant drug may improve response in patients with schizophrenia who also have severe depressive or negative symptoms. For multi-episode patients with an inadequate response to an adequate dose and duration of the initial antipsychotic choice, switching to another antipsychotic, with a different receptor profile, may improve response, although evidence is very limited. In first-episode patients, a recent study on switching to another antipsychotic, with a different receptor profile after 4 weeks demonstrated no beneficial effects. There is little evidence to support using doses above the therapeutic range other than in exceptional circumstances., Conclusions: Our review of recent studies using meta-analytic techniques has provided evidence that all antipsychotics are not equal in the severity of different side effects and in some measures of clinical efficacy. Comparative analysis and rankings from network meta-analyses can provide guidance to clinicians in choosing the most appropriate antipsychotic for first-line treatment, if used in conjunction with available information of the patient's history of previous clinical response or higher risks for specific side effects.

Rationale: Psychopharmacology needs novel quantitative measures and theoretical approaches based on computational modelling that can be used to help translate behavioural findings from experimental animals to humans, including patients with neuropsychiatric disorders. Objectives: This brief review exemplifies this approach when applied to recent published studies of the effects of manipulating central dopaminergic and serotoninergic systems in rodents and marmoset monkeys, and possible comparisons with healthy human volunteers receiving systemic agents or patients with depression and schizophrenia. Methods: Behavioural effects of central depletions of dopamine or serotonin in monkeys in probabilistic learning paradigms are characterised further by computational modelling methods and related to rodent and human data. Results: Several examples are provided of the power of computational modelling to derive new measures and reappraise conventional explanations of regional neurotransmitter depletion and other drug effects, whilst enhancing construct validation in patient groups. Specifically, effects are shown on such parameters as 'stimulus stickiness' and 'side stickiness', which occur over and above effects on standard parameters of reinforcement learning, reminiscent of some early innovations in data analysis in psychopharmacology. Conclusions: Computational modelling provides a useful methodology for further detailed analysis of behavioural mechanisms that are affected by pharmacological manipulations across species and will aid the translation of experimental findings to understand the therapeutic effects of medications in neuropsychiatric disorders, as well as facilitating future drug discovery. [ABSTRACT FROM AUTHOR]