Atypical Antipsychotic Profile Research Articles

Design, Synthesis, Molecular Docking, and Preliminary Pharmacological Screening of some New Benzo[d]thiazol-2-ylamino Containing Chromen-2- one Derivatives with Atypical Antipsychotic Profile.

Mental disorders are very serious complicated disorders. Schizophrenia is one of the most baffling mental disorders. The new series 7-(2-(benzo[d]thiazol-2- ylamino)ethoxy)-4-methyl-2H-chromen-2- synthesized in search of newer compounds for Schizophrenia. Synthesis is done by refluxing in dry pyridine with various substituted 2-amino benzothiazoles derivatives (3a-3k) and 7-(2-Chloroethoxy)-4-methyl-2H-chromen-2-one (2). The molecular docking approach was used to screen these generated derivatives. Chem Bio Draw Ultra 12 was used to draw the compounds, which were then exposed to all potential conformations of compounds interacting with receptors. The Glide 7.6, Schrodinger 2017 Maestro 11.3 was used to achieve molecular docking. The Dopamine receptor 6CM4 serotonin 5TUD PDBs were acquired from the database of Brookhaven Protein. Using the OPLS 2005 force field, the ligand-protein hydrogen-bond network was acquired, along with the overall energy reduced. A glide score was used to rate the docking poses. The produced compounds have been identified with the use of analytical and spectral data. All of the produced substances were tested and analyzed for serotonin 5HT2 antagonistic and dopamine D2 activity, which can be considered as a measure of typical antipsychotic properties. Compounds 4b, 4c, 4e, 4g & 4i have demonstrated promising pharmacological action in preliminary studies. According to the preceding findings, compounds with electronwithdrawing substitutions, such as 4e & 4b, have a good atypical profile of antipsychotics.

Cannabidiol Displays Proteomic Similarities to Antipsychotics in Cuprizone-Exposed Human Oligodendrocytic Cell Line MO3.13.

Cannabidiol, a compound of Cannabis sativa, has been proposed as an alternative treatment of schizophrenia. Preclinical and clinical data have suggested that cannabidiol shares more similarity with atypical antipsychotics than typical, both of which are customarily used to manage schizophrenia symptoms. While oligodendrocytes are known to be relevant targets of antipsychotics, the biochemical knowledge in this regard is still limited. Here we evaluated the molecular pathways modulated by cannabidiol compared to the antipsychotics clozapine (atypical) and haloperidol (typical), additionally evaluating the effects of benztropine, a muscarinic receptor antagonist that displays a protective effect in oligodendrocytes and myelination. For this purpose, we employed nano-chromatography coupled with mass spectrometry to investigate the proteomic response to these drugs both in healthy oligodendrocytic cells and in a cuprizone-based toxicity model, using the human oligodendrocyte precursor cell line MO3.13. Cannabidiol shares similarities of biochemical pathways with clozapine and benztropine, in agreement with other studies that indicated an atypical antipsychotic profile. All drugs tested affected metabolic and gene expression pathways and cannabidiol, benztropine, and clozapine modulated cell proliferation and apoptosis when administered after cuprizone-induced toxicity. These general pathways are associated with cuprizone-induced cytotoxicity in MO3.13 cells, indicating a possible proteomic approach when acting against the toxic effects of cuprizone. In conclusion, although modeling oligodendrocytic cytotoxicity with cuprizone does not represent the entirety of the pathophysiology of oligodendrocyte impairments, these results provide insight into the mechanisms associated with the effects of cannabidiol and antipsychotics against cuprizone toxicity, offering new directions of study for myelin-related processes and deficits.

One Pot Synthesis and Pharmacological Evaluation of Aryl Substituted Imidazoles as Potential Atypical Antipsychotics

Background: Second generation or “atypical” antipsychotics demonstrate an improved therapeutic profile over conventional neuroleptics. These are effective in both positive and negative symptoms of the disease and have a lower propensity to induce adverse symptoms. Objective: The main objective of the research was in silico design and synthesis of potential atypical antipsychotics with combined antiserotonergic / antidopaminergic effect. Methods: A one pot synthesis of aryl substituted imidazole derivatives was carried out in green solvent PEG-400 and the prepared compounds were evaluated for atypical antipsychotic activity in animal models for dopaminergic and serotonergic antagonism. The compounds were designed based on their 3D similarity studies to standard drugs and in silico (docking studies) with respect to 5-HT2A and D2 receptors. Results: Results from the docking studies with respect to 5-HT2A and D2 receptors suggested a potential atypical antipsychotic profile for the test compounds. Theoretical ADME profiling of the compounds based on selected physicochemical parameters suggested an excellent compliance with Lipinski’s rules. The potential of these compounds to penetrate the blood brain barrier (log BB) was computed through an online software program and the values obtained for the compounds suggested a good potential for brain permeation. Reversal of apomorphine induced mesh climbing behaviour coupled with inactivity in the stereotypy assay indicates antidopaminergic effect and a potential atypical profile for the test compounds 1-5. Further, the activity of compounds in DOI assay indicated a 5-HT2 antagonistic profile (5-HT2 antagonism). Conclusion: Compound 5 emerged as important lead compound showing combined antidopaminergic and antiserotonergic (5-HT2A) activity with a potential atypical antipsychotic profile.

N-(2-Hydroxyphenyl)-1-[3-(2-oxo-2,3-dihydro-1H- benzimidazol-1-yl)propyl]piperidine-4-Carboxamide (D2AAK4), a Multi-Target Ligand of Aminergic GPCRs, as a Potential Antipsychotic.

N-(2-hydroxyphenyl)-1-[3-(2-oxo-2,3-dihydro-1H-benzimidazol -1-yl)propyl]piperidine-4-carboxamide (D2AAK4) is a multitarget ligand of aminergic G protein-coupled receptors (GPCRs) identified in structure-based virtual screening. Here we present detailed in vitro, in silico and in vivo investigations of this virtual hit. D2AAK4 has an atypical antipsychotic profile and low affinity to off-targets. It interacts with aminergic GPCRs, forming an electrostatic interaction between its protonatable nitrogen atom and the conserved Asp 3.32 of the receptors. At the dose of 100 mg/kg D2AAK4 decreases amphetamine-induced hyperactivity predictive of antipsychotic activity, improves memory consolidation in passive avoidance test and has anxiogenic properties in elevated plus maze test (EPM). Further optimization of the virtual hit D2AAK4 will be aimed to balance its multitarget profile and to obtain analogs with anxiolytic activity.

Synthesis and Biological Evaluation of Five-Atom-Linker-Based Arylpiperazine Derivatives with an Atypical Antipsychotic Profile.

Herein we describe a focused set of new arylpiperazine derivatives as potential broad-spectrum antipsychotics. The general structure contains a quinolinone-like moiety, an arylpiperazine moiety, and a five-atom linker. Among them, 7-(5-(4-(benzo[d]isothiazol-4-yl)piperazin-1-yl)pentyl)quinolin-2(1H)-one (S6) shows a promising preclinical profile. Compound S6, characterized by partial D2 R agonism, 5-HT1A R agonism, 5-HT2A R antagonism, and blockade of SERT activities, was found to decrease psychosis- and depressive-like symptoms in rodents. The polypharmacological profile of S6 could provide opportunities for the treatment of various other central nervous system disorders such as anxiety, depression, and psychoses associated with dementia. Furthermore, S6 demonstrated acceptable safety, toxicology, and pharmacokinetic profiles, and has been selected as a preclinical candidate for further evaluation in schizophrenia.

Synthesis and Evaluation of Aryl Substituted Propyl Piperazines for Potential Atypical Antipsychotic Activity.

Schizophrenia is a disorder with complex etiology with hyperdopaminergia as the leading underlying cause. Atypical antipsychotics are the agents which do not give rise to significant extrapyramidal side effects and are more effective against negative symptoms of schizophrenia. A new series of chloro-substituted substituted aryloxypiperazine derivatives and their indole based derivatives was designed and evaluated for atypical antipsychotic activity based on established models for combined dopaminergic and serotonergic antagonism. The present series of compounds were designed based on 3D similarity studies, synthesized and evaluated for atypical antipsychotic activity in animal models for combined dopaminergic and serotonergic antagonism. The blood-brain barrier penetration potential was assessed from theoretical log BB values computed through an online software program. Theoretical ADME profiling of the designed compounds based on selected physicochemical parameters suggested excellent compliance with Lipinski's rules. The log BB values obtained for the compounds suggested a good potential for brain permeation. Indole substitution contributed towards an improved efficacy over aryloxy analogs. Lead compounds showed a potential for combined dopaminergic and serotonergic antagonism. The 5-methoxy indole based compounds 16 and 17 were identified as the lead compounds displaying a potential atypical antipsychotic profile.

Antidepressant effect of atypical antipsychotic ziprasidone in albino rats

Background: Depression is a common psychiatric illness but conventional antidepressants are often shows unpredictable response. Pharmacological profiles of many atypical antipsychotics have potential antidepressant effect. Ziprasidone is an atypical antidepressant with 5HT1A agonistic activity and 5HT1D, 5HT2A and D2 receptors antagonistic activity. It’s a potential candidate for evaluating possible antidepressant activity.Methods: Behavioural despair test are widely used for evaluation of potential antidepressant molecule. Tail suspension test is a variant of behavioural despair test. Healthy male Wistar albino rat 18 in number and weighing between of 150-200 grams were divided in 3 groups with 6 rats in each group. Group A was treated with 0.9% Normal Saline, Group B with Fluoxetine and Group C with Ziprasidone for 28 days. Tail suspension test was done on day 0, 7, 14, 21 and 28 days.Results: In comparison to Normal saline both the drugs shows significant antidepressant activity after 28 days of treatment. While antidepressant activity of fluoxetine started to appear from day 7; that of ziprasidone started to appear from 14th day.Conclusions: Ziprasidone can be suitable candidate for clinical trials of Major Depressive Disorders not responding to conventional antidepressant.

Synthesis and biological investigation of new equatorial (β) stereoisomers of 3-aminotropane arylamides with atypical antipsychotic profile

A series of novel 3β-aminotropane derivatives containing a 2-naphthalene or a 2-quinoline moiety was synthesised and evaluated for their affinity for 5-HT1A, 5-HT2A and D2 receptors. Their affinity for the receptors was in the nanomolar to micromolar range. p-Substitution (6c, 6f, 6i, 6l, 6o), as well as substitution with chlorine atoms (6g, 6h, 6i), led to a significant increase in binding affinity for D2 receptors with compounds 6f (Ki=0.6nM), 6c and 6i (Ki=0.4nM), having the highest binding affinities. m-Substituted derivatives were the most promising ligands in terms of 5-HT2A receptor binding affinity whereas 2-quinoline derivatives (10a, 10b) displayed the highest affinity for 5-HT1AR and were the most selective ligands with Ki=62.7nM and Ki=30.5nM, respectively. Finally, the selected ligands 6b, 6d, 6e, 6g, 6h, 6k, 6n and 6o, with triple binding activity for the D2, 5-HT1A and 5-HT2A receptors, were subjected to in vivo tests, such as those for induced hypothermia, climbing behaviour and the head twitch response, in order to determine their pharmacological profile. The tested ligands presented neither agonist nor antagonist properties for the 5-HT1A receptors in the induced hypothermia and lower lip retraction (LLR) tests. All tested compounds displayed antagonistic activity against 5-HT2A, with 6n and 6o being the most active. Four (6b, 6k, 6n and 6o) out of eight tested compounds could be classified as D2 antagonists. Additionally, evaluation of metabolic stability was performed for selected ligands, and introduction of halogen atoms into the benzene ring of 6h, 6k, 6n and 6o improved their metabolic stability. The project resulted in the selection of the lead compounds 6n and 6o, which had antipsychotic profiles, combining dopamine D2-receptor and 5-HT2A antagonism and metabolic stability.

Targeting dopamine D3 and serotonin 5-HT1A and 5-HT2A receptors for developing effective antipsychotics: synthesis, biological characterization, and behavioral studies.

Combination of dopamine D3 antagonism, serotonin 5-HT1A partial agonism, and antagonism at 5-HT2A leads to a novel approach to potent atypical antipsychotics. Exploitation of the original structure-activity relationships resulted in the identification of safe and effective antipsychotics devoid of extrapyramidal symptoms liability, sedation, and catalepsy. The potential atypical antipsychotic 5bb was selected for further pharmacological investigation. The distribution of c-fos positive cells in the ventral striatum confirmed the atypical antipsychotic profile of 5bb in agreement with behavioral rodent studies. 5bb administered orally demonstrated a biphasic effect on the MK801-induced hyperactivity at dose levels not able to induce sedation, catalepsy, or learning impairment in passive avoidance. In microdialysis studies, 5bb increased the dopamine efflux in the medial prefrontal cortex. Thus, 5bb represents a valuable lead for the development of atypical antipsychotics endowed with a unique pharmacological profile for addressing negative symptoms and cognitive deficits in schizophrenia.

A systematic microdialysis study of dopamine transmission in the accumbens shell/core and prefrontal cortex after acute antipsychotics.

The only systematic in vivo studies comparing antipsychotic (AP) effects on nucleus accumbens (NAc) shell and core dopamine (DA) transmission are voltammetric studies performed in pargyline-pretreated, halothane-anaesthetized rats. Studies in freely moving rats not pretreated with pargyline are not available. This study was intended to fill this gap by the use of in vivo microdialysis in freely moving rats. Male Sprague-Dawley rats were implanted with microdialysis probes in the NAc shell and core and medial prefrontal cortex (PFCX). The next day, rats were administered intravenously with two or three doses of APs, and dialysate DA was monitored in 10-min samples. Some rats were pretreated with pargyline (75mg/kg i.p.) and after 1h were given clozapine or risperidone. Clozapine, risperidone, quetiapine, raclopride, sulpiride and amisulpride increased DA preferentially in the NAc shell. Such preferential effect on shell DA was not observed after haloperidol, chlorpromazine and olanzapine. In contrast to voltammetric studies, a preferential effect on NAc core DA was not observed after any dose of AP. Pargyline pretreatment did not reduce but actually amplified the preferential effect of clozapine and risperidone on NAc shell DA. Apart from raclopride and olanzapine, the APs with lower extrapyramidal effects could be distinguished from typical APs on the basis of their ability to preferentially stimulate DA transmission in the NAc shell. There was no relationship between stimulation of PFCX DA and atypical APs profile. The differences between this study and voltammetry studies were not attributable to pargyline pretreatment.

The Influence of Antipsychotics on the Quality of Life of Patients with Schizophrenia in a Long-stay Psychiatric Facility

ABSTRACT Introduction: Many factors concomitantly influence the quality of life of patients with schizophrenia in a long-stay psychiatric facility. Th e appropriate selection of antipsychotics and the intensity of their adverse effects exert a significant influence on the quality of life of these patients. Th e aim of this study was to identify the influence of antipsychotic-related factors on the quality of life of patients with schizophrenia. Methods: Th e study included 102 beneficiaries at the Institute for Accommodation of Adults “Male Pčelice” in Kragujevac. Th e patients were interviewed on in one day using the questionnaire issued by the World Health Organization. The specified data were obtained from the health files of the beneficiaries. We performed a comparison between patients receiving only atypical antipsychotics, typical antipsychotics or a combination thereof. Results: Th e patients who were receiving only atypical antipsychotics demonstrated better physical health quality of life scores in comparison to those who received combined antipsychotics (77.14 vs. 68.57; U = 332.0; p = 0.02). A statistically significant difference in the mental health quality of life domain was observed between groups of patients receiving various antipsychotic treatments (31.96 vs. 55.27 vs. 49.46; c2 = 7.02; p = 0.03). Conclusion: Patients in a long-stay psychiatric facility who received atypical antipsychotics demonstrated a better quality of life in comparison to those who received typical antipsychotics, possibly due to the superior safety profile of atypical antipsychotics and a greater feeling of individual contentment.

Role of atypical antipsychotics in the treatment of generalized anxiety disorder.

Evidence-based treatment approaches for generalized anxiety disorder (GAD) comprise psychotherapy, pharmacotherapy, or a combination of the two. First-line pharmacotherapy agents include selective serotonin reuptake inhibitors, selective serotonin-norepinephrine reuptake inhibitors, and, in certain European guidelines, pregabalin, which gained European Commission approval. Although short- and long-term efficacy have been established for these agents in controlled trials, response rates of 60-70 % are insufficient, remission rates are relatively modest, and relapse rates considerable. Moreover, questions increasingly arise regarding tolerability and side-effect profiles. As an alternative, antipsychotics have long been of interest for the treatment of anxiety disorders, but investigation had been tempered by their potential for irreversible side effects. With the improved side-effect profiles of atypical antipsychotics, these agents are increasingly being investigated across Axis I disorders. Atypical antipsychotics such as quetiapine, aripiprazole, olanzapine, and risperidone have been shown to be helpful in addressing a range of anxiety and depressive symptoms in individuals with schizophrenia and schizoaffective disorders, and have since been used in the treatment of a range of mood and anxiety disorders. In this article, we review the efficacy and tolerability of atypical antipsychotics as adjunctive therapy and/or monotherapy for individuals with GAD, a currently off-label indication. The most evidence has accumulated for quetiapine. Findings suggest that approximately 50 % of participants tolerate the side effects, most commonly sedation and fatigue. Among this subset, those who continue treatment demonstrate significant reductions in anxiety when used as adjunctive therapy or monotherapy. The appropriateness of the use of antipsychotics in the treatment of GAD is discussed.

Synthesis and biological evaluation of a series of aminoalkyl-tetralones and tetralols as dual dopamine/serotonin ligands

A series of novel α-tetralone and α-tetralol derivatives was synthesized, and their binding affinities for 5-HT2A and D2 receptors, the most important targets implicated in the anti-schizophrenia drug action, were evaluated to elucidate how substitutions in the aromatic ring of the pharmacophore affect to the affinity or selectivity for these receptors. The replacement of the H-7 in the tetrahydronaphthalene system by an amino group resulted in privileged 5-HT2A affinity of the 6-fluorobenzo[d]isoxazol derivative 36 and the alcohol 25 both showing a pKi value for 5-HT2A higher than 8.3 and good binding affinities for D2 receptor leading to a Meltzer's ratio characteristic of an atypical antipsychotic profile. Additionally, a small collection of 3-aminomethyltetralone derivatives was prepared and examined here for their affinities and selectivities as 5-HT2A/D2 dual ligands. Compound 11 shows the best profile with good pKi values for 5-HT2A and D2 receptors leading to a Meltzer's ratio characteristic of a typical antipsychotic behaviour. These three compounds behaved as competitive antagonists of both 5-HT2A and D2 receptors, and might be promising pharmacological tools for the investigation of the dual function of the 5HT2A-D2 ligands.

Typical and atypical antipsychotics do not differ markedly in their reversibility of antagonism of the dopamine D2 receptor

It has been suggested that the favorable side-effect profiles of atypical antipsychotics (e.g. clozapine and amisulpride) are related to their ∼100-fold faster dissociation from dopamine D2 receptors (D2R) compared with typical antipsychotics (e.g. haloperidol and chlorpromazine). Fast dissociation would entail rapidly reversible antagonism; however, this has not been thoroughly studied using functional assays. We compared the reversibilities of D2R antagonism by 17 compounds using an electrophysiological method to measure dopamine-evoked potassium channel activation via D2R. Varying rates and amplitudes of D2R response recovery were observed following antagonist removal. Whereas recovery rates differed 15-fold between atypical drugs, recovery from clozapine and amisulpride antagonism was, unexpectedly, less than twofold faster than from chlorpromazine. The recovery amplitude correlated with calculated water solubility and lipid/water distribution coefficients, suggesting variable drug partitioning into cell membranes. Our data do not support the notion that the rate of reversibility of D2R antagonism is what distinguishes atypical from typical antipsychotics.

Synthesis, docking and pharmacological evaluation of novel indole based potential atypical antipsychotics

A series of substituted indole derivatives have been synthesized and the target compounds evaluated for atypical antipsychotic activity in apomorphine induced mesh climbing and stereotypy assays in mice. The compounds 11 and 12 have emerged as important lead compounds showing potential atypical antipsychotic profile. In silico (docking studies) have been carried out to postulate a hypothetical binding model for the target compounds with respect to the dopaminergic D2 and 5-HT2A receptors. Theoretical ADME profiling of the compounds based on selected physicochemical parameters has suggested an excellent compliance with Lipinski's rules. The potential of these compounds to penetrate the blood brain barrier (log BB) was computed through an online software program and the values obtained for the compounds suggest good potential for brain permeation.

Iptakalim Preferentially Decreases Nicotine-induced Hyperlocomotion in Phencyclidine-sensitized Rats: A Potential Dual Action against Nicotine Addiction and Psychosis

ObjectiveIptakalim is a putative ATP-sensitive potassium (KATP) channel opener. It is also a novel nicotinic acetylcholine receptor (nAChR) blocker and can antagonize nicotine-induced increase in dopamine release in the nucleus accumbens. Our recent work also shows that iptakalim exhibits a clozapine-like atypical antipsychotic profile, indicating that iptakalim may possess a dual action against nicotine addiction and schizophrenia.MethodsThe present study examined the potential therapeutic effects of iptakalim on nicotine use in schizophrenia. We created an animal model of comorbidity of nicotine addiction and schizophrenia by injecting male Sprague-Dawley rats with nicotine (0.40 mg/kg, subcutaneously[sc]) or saline, in combination with phencyclidine (PCP, 3.0 mg/kg, sc) or saline daily for 14 consecutive days.ResultsDuring the PCP/nicotine sensitization phase, PCP and nicotine independently increased motor activity over time. PCP also disrupted prepulse inhibition (PPI) of acoustic startle response. Acute nicotine treatment attenuated the PCP-induced hyperlocomotion and PCP-induced disruption of PPI, whereas repeated nicotine treatment potentiated these effects. Importantly, pretreatment with iptakalim (10-20 mg/kg, intraperitoneally) reduced nicotine-induced hyperlocomotion in a dose-dependent fashion. This reduction effect was highly selective: it was more effective in rats previously sensitized to the combination of PCP and nicotine, but less effective in rats sensitized to saline, nicotine alone or PCP alone.ConclusionTo the extent that the combined nicotine and PCP sensitization mimics comorbid nicotine addiction in schizophrenia, the preferential inhibitory effect of iptakalim on nicotine-induced hyperlocomotion suggests that iptakalim may be a potential useful drug for the treatment nicotine abuse in schizophrenia.

Synthesis and evaluation of meta substituted 1-(aryloxypropyl)-4-(chloroaryl) piperazines as potential atypical antipsychotics

A series of 1-(aryloxypropyl)-4-(chloroaryl) piperazines have been synthesized based upon their physicochemical similarity with respect to standard atypical antipsychotic drugs and their potential to cross the blood–brain barrier (log BB) as calculated by appropriate software programmes. The target compounds were evaluated for atypical antipsychotic activity in apomorphine-induced mesh climbing and stereotypy assays in mice. The compounds 8, 9 and 10 bearing hydrogen bond acceptor substituents have emerged as important lead compounds showing higher efficacy along with potential atypical antipsychotic profile.

Involvement of histamine receptors in the atypical antipsychotic profile of clozapine: a reassessment in vitro and in vivo

The basis of the unique clinical profile of the antipsychotic clozapine is not yet elucidated. Brain histamine receptors may play a role in schizophrenia and its treatment, but their involvement in the profile of clozapine remained unknown. We explored the properties of clozapine and its two metabolites, N-desmethylclozapine (NDMC) and clozapine N-oxide, at the four human histaminergic receptors. We compared their active concentrations with their blood concentrations in patients treated by clozapine. We investigated the changes in receptor densities induced in rat brain by repeated administration of a therapeutic dose of clozapine. Clozapine and NDMC behaved as very potent, and partial, H(1)-receptor inverse agonists, weak, and full, H(2)-receptor inverse agonists, moderate, and protean, H(3)-receptor agonists, and moderate, and partial, H(4)-receptor agonists. Taking into account their micromolar mean blood concentrations found in 75 treated patients, and assuming that they are enriched in human brain as they are in rat brain, a full occupation of H(1)-, H(3)-, and H(4)-receptors, and a partial occupation of H(2) receptors, is expected. In agreement, repeated administration of clozapine at a therapeutic dose (20 mg/kg/day for 20 days) induced an up-regulation of H(1)- and H(2)-receptors in rat brain. Clozapine and its active metabolite NDMC interact with the four human histamine receptors at clinically relevant concentrations. This interaction may substantiate, at least in part, the atypical antipsychotic profile of clozapine, as well as its central and peripheral side effects such as sedation and weight gain.

Specific mechanism of action of amisulpride in the treatment of schizophrenia and correlation with clinical response and tolerability

Specific mechanism of action of amisulpride in the treatment of schizophrenia and correlation with clinical response and tolerability Mario F Juruena1, Eduardo Pondé de Sena2, Irismar Reis de Oliveira31Stress and Affective Disorders Programme, Department of Neuroscience and Behaviour, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil; 2Department of Pharmacology, Institute of Health Sciences, Federal University of Bahia, Salvador, Brazil; 3Department of Neurosciences and Mental Health, School of Medicine, Federal University of Bahia, Salvador, BA, BrazilAbstract: The treatment of schizophrenia has advanced because the therapeutic efficacy, tolerability, and safety profiles of atypical antipsychotics seem to be superior to those of classical neuroleptics. Amisulpride is an atypical antipsychotic drug with a unique receptor pharmacology, which is dose-dependent. As could be predicted from the pharmacologic profile of a pure D2/D3 receptor blocker, amisulpride is an atypical antipsychotic agent, effective for positive and negative symptoms, which can bring about additional improvement in the social functioning and quality of life of patients with schizophrenia. Amisulpride has one of the lowest potentials for weight gain of all the antipsychotic agents, and is clearly associated with lower use of anti-parkinsonian medication and with fewer dropouts due to adverse events than conventional antipsychotics. Amisulpride is well tolerated in terms of anxiety and insomnia. Amisulpride has a pronounced prolactin-elevating effect which appears to be independent of dosage and duration of administration. Hyperprolactinemia rapidly reverses after amisulpride discontinuation. Amisulpride benefits patients with negative symptoms, and is the only antipsychotic to demonstrate efficacy in patients with predominantly negative symptoms. Amisulpride maintains its efficacy when used for medium-/long-term treatment, as demonstrated in studies of up to 12 months. Amisulpride has the best evidence as an effective adjunct to clozapine treatment. In conclusion, amisulpride is an antipsychotic agent with proven efficacy and good tolerability.Keywords: antipsychotic agents, amisulpride, adverse events, pharmacology

Preclinical assessment of an adjunctive treatment approach for cognitive impairment associated with schizophrenia using the alpha7 nicotinic acetylcholine receptor agonist WYE-103914/SEN34625

α7 nicotinic acetylcholine receptor (nAChR) agonists are proposed as candidate agents for the adjunctive treatment of cognitive deficits associated with schizophrenia. Despite the pursuit of such an approach clinically, it is surprising that the preclinical profile of pro-cognitive agents in conjunction with antipsychotic drugs is currently unexplored. We determined if the memory-enhancing effects of the selective α7 nAChR agonist WYE-103914 were preserved in the presence of the atypical antipsychotic drug risperidone, and if the antipsychotic-like profile of risperidone was preserved in the presence of WYE-103914. Using the rat novel object recognition (NOR) paradigm, the maintenance of memory-enhancing activity of the α7 nAChR agonist WYE-103914 in the presence of risperidone was examined. Similarly, in the standard tests of antipsychotic-like activity, apomorphine-induced climbing (AIC) in mice and conditioned avoidance responding (CAR) in rats, the preservation of antipsychotic-like activity of risperidone was evaluated in the presence of WYE-103914. WYE-103914 exhibited memory-enhancing activity in rat NOR, and this effect of WYE-103914 was retained in the presence of risperidone. In AIC, the atypical antipsychotic profile of risperidone was not significantly altered by WYE-103914. In contrast, WYE-103914 moderately potentiated the efficacy profile of risperidone in CAR, an effect that did not appear to be convincingly linked to a pharmacokinetic interaction. These data underscore the value of a preclinical evaluation of the adjunctive profile of a memory-enhancing agent in combination with antipsychotics and provide further support to augmentation with α7 nAChR agonists to address the cognitive deficits associated with schizophrenia.