Avaliação pré-clínica da atividade antipsicótica de derivados N-fenilpiperazínicos e N-benziltiazolidínicos

Considerando a necessidade de antipsicóticos mais seguros e eficazes, uma série de derivados N-fenilpiperazínicos funcionalizados e N-benziltiazolidínicos foi planejada e sintetizada pelo Laboratório de Avaliação e Síntese de Substâncias Bioativas (LASSBio-UFRJ) (LASSBio-1412, LASSBio-1413, LASSBio-1414, LASSBio-1415 e LASSBio-1422) e pelo Grupo de Pesquisa em Inovação Terapêutica (GPIT-UFPe) (FPY-1, FPY-2, FPY-3, FPY-5, FPY-6, FPT-1, FPT-2, FPT-4, FPW-1), respectivamente. Objetivos: selecionar os derivados com potencial atividade antipsicótica através do ensaio de climbing induzido por apomorfina, um modelo preditivo de sintomas positivos da esquizofrenia. Avaliar a ocorrência de efeitos motores e neurotoxicidade por catatonia e rota-rod. Avaliar possíveis efeitos adversos por locomoção e tempo de sono barbitúrico. Verificar o perfil de afinidade a receptores através de ensaios de binding. Métodos: para os ensaios de binding foram utilizados cérebros de ratos Wistar para os receptores D2-like, 5-HT1A e 5-HT2A e fígado de coelho e rato para os receptores α1A e α1B. Camundongos CF1 machos foram utilizados para os testes in vivo. As substâncias foram testadas no modelo de climbing induzido por apomorfina e apenas às substâncias capazes de inibir climbing foi dado continuidade ao estudo. Resultados: LASSBio-1412, LASSBio-1413, LASSBio-1422, FPT-2, FPT-4 e FPY-3 inibiram climbing, sem induzir sinais de catatonia, comprometimento motor, alteração do comportamento exploratório e efeito hipnótico-sedativo. Um estudo dose-resposta (0,5 - 30 mg/kg, v.o.) dessas substâncias indicou LASSBio-1412 como o composto mais potente in vivo. In vitro, observou-se que os derivados N-fenilpiperazínicos possuem uma moderada afinidade pelos receptores estudados, demonstrando um perfil de ligação multirreceptor; semelhante aos antipsicóticos atípicos. Por outro lado, os derivados N-benziltiazolidínicos possuem baixa afinidade por esses receptores, sugerindo um mecanismo de ação diferente. Conclusão: Essas moléculas podem representar protótipos promissores para o desenvolvimento de novos antipsicóticos.Considering that more effective and safer drugs to treat schizophrenia are still needed a series of functionalized N-phenylpiperazines and N-benziltiazolidines derivatives were planned and synthesized by Avaliação e Síntese de Substâncias Bioativas Group (LASSBio/UFRJ): (LASSBio-1412, LASSBio-1413, LASSBio-1414, LASSBio-1415 and LASSBio-1422), and Núcleo de Pesquisa em Inovação Terapêutica Group/UFPE: (FPY-1, FPY-2, FPY-3, FPY-5, FPY-6, FPT-1, FPT-2, FPT-4, FPW-1), respectively. The aim of this study was to search the derivatives with potential antipsychotic activity through apomorphine-induced climbing test and binding receptor assaying as well as to evaluate their potential extrapyramidal sideeffects and neurotoxicity by catatonia and rota-rod tests. Adverse effects were also evaluated by open-field test and barbiturate sleeping time. Methods: Binding assays to D2-like, 5-HT1A, and 5-HT2A receptors were performed in brain rat regions and binding to α1A and α1B receptors were performed in rabbit and rat liver, respectively. All compounds were initially tested by mice apomorphine-induced climbing and only those able to inhibit climbing were selected to further studies. Results: LASSBio- 1412, LASSBio-1413, LASSBio-1422, FPT-2, FPT-4 and FPY-3 inhibited climbing without inducing catatonic behavior, general motor impairment, exploratory behavior alterations or hypnotic-sedative effect. A dose-responde study pointed LASSBio- 1412 as the most potent compound in vivo. In vitro, the N-fenilpiperazines derivatives demonstrated a moderate affinity to the studied receptors, demonstrating a multireceptor profile characteristic of atypical antipsychotics. In a different way, the Nbenziltizolidines derivatives have a low affinity to these receptors, suggesting that these compounds could be acting through a different action mechanism. Conclusion: These compounds are promising molecules to antipsychotics development

USO DE ANTIDEPRESSIVOS E ANTICONVULSIVANTES NO TRATAMENTO DA NEUROPATIA DIABÉTICA: UMA REVISÃO

Este trabalho tem por objetivo revisar a eficácia de antidepressivos e anticonvulsivantes na neuropatia diabética e estratificá-los. Foi realizada uma revisão de artigos publicados de 2000 a 2015 nas bases de dados PubMed, ScienceDirect, Portal de Periódicos Capes e Scielo. Entre os 34 estudos clínicos revisados, 44,18% estudaram o uso de anticonvulsivantes, 32,35% compararam a eficácia de antidepressivos com anticonvulsivantes e 23,52% estudaram o uso de antidepressivos. Estudos com anticonvulsivantes foram os mais numerosos, reduzindo a dor em 86,67%. Os antidepressivos, apesar do menor número de estudos, demonstraram eficácia no tratamento em 100%. Os estudos com antidepressivos e anticonvulsivantes apontam para uma eficácia semelhante

Plants with potencial antifungal activity employed in Brazilian folk medicine

Neste trabalho foi realizado um levantamento bibliográfico etnobotânico sobre plantas utilizadas pela população brasileira no tratamento de sinais e sintomas relacionados às infecções fúngicas. Foram citadas 409 espécies, distribuídas em 98 famílias, com maior concentração em Fabaceae e Asteraceae. Para as dez espécies mais citadas, foi realizada uma busca relativa a estudos de atividade antifúngica na base de dados MEDLINE-PubMed. Somente foram encontrados estudos para Phytolacca americana L., Rosmarinus officinalis L., Mirabilis jalapa L., Schinus molle L. Entre as dez espécies mais utilizadas, seis correspondem a espécies nativas: Anacardium occidentale L., Cecropia peltata L., Schinus molle L., Schinus terebinthinfolius Raddi, Stryphnodendron adstringens (Mart.) Coville e Tabebuia heptaphylla (Vell.) Toledo.The aim of this work was to draw up a list of plants used by Brazilian population for the treatment of signs and symptoms related to fungal infections and to verify the existence of scientific data related to the antifungal activity in the databasis MEDLINE-PubMed. Four hundread and nine species were listed, which are distributed in ninety eight families, mainly Fabaceae and Asteraceae. Among the more frequently mentioned species (10), only four were evaluated regarding to the antifungal activity: Phytolacca americana L., Rosmarinus officinalis L., Mirabilis jalapa L. and Schinus molle L. From those ten species, six are native (Anacardium occidentale L., Cecropia peltata L., Schinus molle L., Schinus terebinthifolius Raddi, Stryphnodendron adstringens (Mart.) Coville e Tabebuia heptaphylla (Vell.) Toledo

Evaluation of the potential toxicity of haloperidol, clozapine and a new putative antipsychotic molecule, PT-31, in an alternative toxicity model, C. elegans

Schizophrenia is a disabling mental illness that affects approximately 1% of the world population. The treatment of this disorder is based on two generations of substances, typical antipsychotics, such as haloperidol, and atypical antipsychotics, such as clozapine, which can cause severe adverse effects. Therefore, the development of novel molecules that are safe and efficacious to treat the disease is crucial. PT-31 is a putative α2-adrenoceptor agonist effective against schizophrenia positive and cognitive symptoms in mice. C. elegans is an alternative model that has been successfully used to investigate the toxicity of a variety of substances. The present study aimed to evaluate the potential toxicity of the new molecule PT-31 and the antipsychotics haloperidol and clozapine in C. elegans. The evaluation was carried out based on toxicity endpoint tests, survival, developmental and behavioral assays. The antipsychotics haloperidol and clozapine decreased nematode survival by 30 and 40%, respectively, exposing the potential toxicity of these substances whereas PT-31 was safer based on this parameter. Similar results were obtained in the nematode developmental assay: haloperidol and clozapine significantly reduced nematode body length and area, whereas PT-31 preserved the normal development of the nematodes. The behavioral assessment was based on the frequency of body bends; none of the antipsychotics affected the locomotion rate of the nematodes, and PT-31 also did not compromise this parameter, demonstrating the safety of this new compound and reinforcing the recognized toxicity of antipsychotics

Neurotoxicity evaluation of meloxicam in the alternative in vivo model, Caenorhabditis elegans

Inflammatory processes cause changes in the permeability of the blood brain barrier. Non-steroidal anti-inflammatory drugs (NSAID) are most commonly used to treat these inflammatory processes, including meloxicam, and they can reach the central nervous system (CNS) and cause neurotoxicity. Since there are no studies evaluating the neurotoxicity of NSAID in alternative models of toxicity, the aim of this study was to evaluate the acute neurotoxicity (through nematodes changes in behavior) of meloxicam in an alternative in vivo model, Caenorhabditis elegans, as well as, to determine meloxicam toxicity through LD50 and development assessments. Meloxicam LD50 was high (50.03 mg/mL) and only the highest dose (100 mg/mL) caused a decrease in the nematode body size, indicating low toxicity in this alternative model. Besides, a neurological effect was observed only in the highest dose. Meloxicam showed neurotoxicity only at a very high dose, suggesting low potential to cause toxicity in the CNS. However, further studies are necessary to evaluate meloxicam neurotoxicity

Cytotoxicity evaluation of haloperidol, clozapine and a new molecule with antipsychotic potential, PT-31, in NIH-3T3 cells

Schizophrenia is an illness that affects 26 million people worldwide. However, conventional antipsychotics present side effects and toxicity, highlighting the need for new antipsychotics. We aimed to evaluate the cytotoxicity of haloperidol (HAL), clozapine (CLO), and a new molecule with antipsychotic potential, PT-31, in NIH-3T3 cells. The neutral red uptake assay and the MTT assay were performed to evaluate cell viability and mitochondrial activity, morphological changes were assessed, and intracellular reactive oxygen species (ROS) detection was performed. HAL and CLO (0.1 μM) showed a decrease in cell viability in the neutral red uptake assay and in the MTT assay. In addition, cell detachment, content decrease, rounding and cell death were also observed at 0.1 μM for both antipsychotics. An increase in ROS was observed for HAL (0.001, 0.01 and 1 μM) and CLO (0.01 and 1 μM). PT-31 did not alter cell viability in any of the assays, although it increased ROS at 0.01 and 1 μM. HAL and CLO present cytotoxicity at 0.1 μM, possibly through apoptosis and necrosis. In contrast, PT-31 does not present cytotoxicity to NIH-3T3 cells. Further studies must be performed for a better understanding of these mechanisms and the potential risk of conventional antipsychotics

Determination of oxidative stress parameters in fluoxetine users

Fluoxetine (FLU), a selective serotonin reuptake inhibitor, is the first line in depression treatment and it is involved in oxidative stress (OE). Thus, this study aimed to analyze the OE parameters in patients diagnosed with depression and treated with FLU. Were evaluated 121 volunteers divided into two groups: 58 fluoxetine users (with major depression) and 63 non-fluoxetine users (control group, without major depression). The OE was evaluated by determining the levels of malondialdehyde (MDA), total antioxidant power (FRAP) and activity of antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD). MDA, FRAP, GPx and SOD were dosed in plasma. The influence of age, smoking, alcoholism, comorbidities, use of another drugs and antioxidants in the OE were evaluated. The results were compared between the groups. In relation to the fluoxetine daily dose, MDA presented higher levels in patients using 20 mg daily FLU when compared to the control group, as well as the activity of the GPx enzyme and the FRAP levels. In this way, the use of fluoxetine may interfere with the OE parameters, causing an increase in OE levels

Searching for new chemical entities for the development of new antipsychotic drugs : preclinical evaluation of N-phenylpiperazine, N-benziltiazolidine and imidazolidine derivatives

A esquizofrenia é uma doença que acomete cerca de 1% da população mundial. Existem mais de vinte fármacos antipsicóticos disponíveis no mercado, entretanto, pelo menos um terço dos pacientes é refratário ao tratamento ou descontinuam a terapia devido à baixa tolerabilidade ou eficácia incompleta desses medicamentos. No âmbito desta Tese de Doutorado, inserida em um Programa de Desenvolvimento de Novos Fármacos, novas moléculas com padrões moleculares distintos (LASSBio-1422, derivado Nfenilpiperazínico; FPY-3, derivado N-benziltiazolidínico; PT-31, derivado imidazolidínico) foram estudadas, visando à descoberta de novos agentes terapeuticamente úteis no tratamento da esquizofrenia. Essas moléculas foram avaliadas em modelos animais preditivos de sintomas positivos da esquizofrenia (escalada induzida por apomorfina e hiperlocomoção induzida por cetamina), modelo que avalia o estado pré-atencional (inibição de sobressalto por pré-pulso), modelo de memória (reconhecimento de objeto novo), e modelos animais que avaliam sintomas extrapiramidais, efeitos motores e sedação (catatonia, locomoção, rota-rod e tempo de sono barbitúrico). LASSBio-1422, um antagonista de receptores do tipo D4, mostrou-se eficaz em modelos animais preditivos de sintomas positivos da esquizofrenia, sem causar prejuízo motor nem sedação. Além disso, preveniu o prejuízo pré-atencional induzido por apomorfina, (±)-DOI e cetamina. Ainda, não comprometeu as memórias de curta e longa duração, além de proteger a última contra o prejuízo induzido pela cetamina. FPY-3 também foi efetivo nos modelos animais preditivos de sintomas positivos da esquizofrenia, sem causar efeitos extrapiramidais, motores e sedação. A maior contribuição dessa molécula foi a ausência de toxicidade após 14 dias de tratamento, sugerindo uma melhora no metabolismo lipídico, com menor incidência de síndrome metabólica, um dos principais efeitos adversos da segunda geração de antipsicóticos. FPY-3 também protegeu neurônios primários cerebelares contra a toxicidade induzida pelo glutamato. PT-31, por sua vez, possui um padrão molecular inédito, nunca antes estudado para atividade antipsicótica. PT-31, um agonista α2A-adrenérgico, mostrou-se eficaz no tratamento de sintomas positivos e, principalmente, cognitivos, que ainda representam um dos principais desafios no tratamento da esquizofrenia. Ainda mostrou um efeito neuroprotetor em cultura primária de neurônios. Por fim, sugerimos que LASSBio-1422, FPY-3 e PT-31 possam representar moléculas promissoras para inclusão em estratégias de desenvolvimento de novos fármacos para o tratamento da esquizofrenia.Schizophrenia is a disease that affects around 1% of the world population. There are more than twenty antipsychotic drugs available on the market, however, at least one third of patients are refractory to the treatment or discontinuing therapy due to the poor tolerability or incomplete efficacy of these drugs. In the present Thesis, inserted into a New Drugs Development Program, new molecules with distinct molecular patterns (LASSBio-1422, N-phenylpiperazine derivative; FPY-3, N-benziltiazolidine derivative; PT-31, imidazolidine derivative) were studied, aiming to discover new agents therapeutically useful in the treatment of schizophrenia.These molecules were evaluated in animal models predictive of schizophrenia positive symptoms (apomorphine-induced climbing and ketamine-induced hyperlocomotion), a model that evaluates the preattentional process (prepulse inhibition), a memory model (novel object recognition task), and models that assess extrapyramidal symptoms, sedation and motor effects (catalepsy, locomotion, rota-rod and barbiturate sleeping time). LASSBio-1422, a D4 antagonist, was effective in animal models predictive of schizophrenia positive symptoms without inducing motor impairment or sedation. Furthermore, it prevented the preattentional injury induced by apomorphine, (±)-DOI and ketamine. Still, it did not compromised short neither long-term memories, and protected the latter against the deficit induced by ketamine. FPY-3 was also effective in animal models predictive of schizophrenia positive symptoms without inducing extrapyramidal symptoms, motor impairment and sedation. The major contribution of this molecule was the lack of toxicity after 14 days of treatment, suggesting an improvement in the lipid metabolism and lower incidence of metabolic syndrome, a major adverse effect of the second generation antipsychotics. FPY-3 also protected cerebellum primary cells against the toxicity induced by glutamate. PT-31, in turn, has a distinct molecular pattern, never before studied for the antipsychotic activity. PT-31, an α2A-adrenoceptor agonist, was effective in treating positive symptoms, and especially in treating cognitive symptoms, which remains a major challenge in the treatment of schizophrenia. It still showed a neuroprotective effect in primary cell cultures. Finally, we suggest that LASSBio-1422, FPY-3 and PT-31 may represent promising molecules for inclusion in strategies for the development of new drugs for treating schizophrenia

Searching for new chemical entities for the development of new antipsychotic drugs : preclinical evaluation of N-phenylpiperazine, N-benziltiazolidine and imidazolidine derivatives

A esquizofrenia é uma doença que acomete cerca de 1% da população mundial. Existem mais de vinte fármacos antipsicóticos disponíveis no mercado, entretanto, pelo menos um terço dos pacientes é refratário ao tratamento ou descontinuam a terapia devido à baixa tolerabilidade ou eficácia incompleta desses medicamentos. No âmbito desta Tese de Doutorado, inserida em um Programa de Desenvolvimento de Novos Fármacos, novas moléculas com padrões moleculares distintos (LASSBio-1422, derivado Nfenilpiperazínico; FPY-3, derivado N-benziltiazolidínico; PT-31, derivado imidazolidínico) foram estudadas, visando à descoberta de novos agentes terapeuticamente úteis no tratamento da esquizofrenia. Essas moléculas foram avaliadas em modelos animais preditivos de sintomas positivos da esquizofrenia (escalada induzida por apomorfina e hiperlocomoção induzida por cetamina), modelo que avalia o estado pré-atencional (inibição de sobressalto por pré-pulso), modelo de memória (reconhecimento de objeto novo), e modelos animais que avaliam sintomas extrapiramidais, efeitos motores e sedação (catatonia, locomoção, rota-rod e tempo de sono barbitúrico). LASSBio-1422, um antagonista de receptores do tipo D4, mostrou-se eficaz em modelos animais preditivos de sintomas positivos da esquizofrenia, sem causar prejuízo motor nem sedação. Além disso, preveniu o prejuízo pré-atencional induzido por apomorfina, (±)-DOI e cetamina. Ainda, não comprometeu as memórias de curta e longa duração, além de proteger a última contra o prejuízo induzido pela cetamina. FPY-3 também foi efetivo nos modelos animais preditivos de sintomas positivos da esquizofrenia, sem causar efeitos extrapiramidais, motores e sedação. A maior contribuição dessa molécula foi a ausência de toxicidade após 14 dias de tratamento, sugerindo uma melhora no metabolismo lipídico, com menor incidência de síndrome metabólica, um dos principais efeitos adversos da segunda geração de antipsicóticos. FPY-3 também protegeu neurônios primários cerebelares contra a toxicidade induzida pelo glutamato. PT-31, por sua vez, possui um padrão molecular inédito, nunca antes estudado para atividade antipsicótica. PT-31, um agonista α2A-adrenérgico, mostrou-se eficaz no tratamento de sintomas positivos e, principalmente, cognitivos, que ainda representam um dos principais desafios no tratamento da esquizofrenia. Ainda mostrou um efeito neuroprotetor em cultura primária de neurônios. Por fim, sugerimos que LASSBio-1422, FPY-3 e PT-31 possam representar moléculas promissoras para inclusão em estratégias de desenvolvimento de novos fármacos para o tratamento da esquizofrenia.Schizophrenia is a disease that affects around 1% of the world population. There are more than twenty antipsychotic drugs available on the market, however, at least one third of patients are refractory to the treatment or discontinuing therapy due to the poor tolerability or incomplete efficacy of these drugs. In the present Thesis, inserted into a New Drugs Development Program, new molecules with distinct molecular patterns (LASSBio-1422, N-phenylpiperazine derivative; FPY-3, N-benziltiazolidine derivative; PT-31, imidazolidine derivative) were studied, aiming to discover new agents therapeutically useful in the treatment of schizophrenia.These molecules were evaluated in animal models predictive of schizophrenia positive symptoms (apomorphine-induced climbing and ketamine-induced hyperlocomotion), a model that evaluates the preattentional process (prepulse inhibition), a memory model (novel object recognition task), and models that assess extrapyramidal symptoms, sedation and motor effects (catalepsy, locomotion, rota-rod and barbiturate sleeping time). LASSBio-1422, a D4 antagonist, was effective in animal models predictive of schizophrenia positive symptoms without inducing motor impairment or sedation. Furthermore, it prevented the preattentional injury induced by apomorphine, (±)-DOI and ketamine. Still, it did not compromised short neither long-term memories, and protected the latter against the deficit induced by ketamine. FPY-3 was also effective in animal models predictive of schizophrenia positive symptoms without inducing extrapyramidal symptoms, motor impairment and sedation. The major contribution of this molecule was the lack of toxicity after 14 days of treatment, suggesting an improvement in the lipid metabolism and lower incidence of metabolic syndrome, a major adverse effect of the second generation antipsychotics. FPY-3 also protected cerebellum primary cells against the toxicity induced by glutamate. PT-31, in turn, has a distinct molecular pattern, never before studied for the antipsychotic activity. PT-31, an α2A-adrenoceptor agonist, was effective in treating positive symptoms, and especially in treating cognitive symptoms, which remains a major challenge in the treatment of schizophrenia. It still showed a neuroprotective effect in primary cell cultures. Finally, we suggest that LASSBio-1422, FPY-3 and PT-31 may represent promising molecules for inclusion in strategies for the development of new drugs for treating schizophrenia