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1.
Int J Mol Sci ; 23(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36555423

RESUMO

Antimicrobial resistance is an old and silent pandemic. Resistant organisms emerge in parallel with new antibiotics, leading to a major global public health crisis over time. Antibiotic resistance may be due to different mechanisms and against different classes of drugs. These mechanisms are usually found in the same organism, giving rise to multidrug-resistant (MDR) and extensively drug-resistant (XDR) bacteria. One resistance mechanism that is closely associated with the emergence of MDR and XDR bacteria is the efflux of drugs since the same pump can transport different classes of drugs. In Gram-negative bacteria, efflux pumps are present in two configurations: a transmembrane protein anchored in the inner membrane and a complex formed by three proteins. The tripartite complex has a transmembrane protein present in the inner membrane, a periplasmic protein, and a porin associated with the outer membrane. In Pseudomonas aeruginosa, one of the main pathogens associated with respiratory tract infections, four main sets of efflux pumps have been associated with antibiotic resistance: MexAB-OprM, MexXY, MexCD-OprJ, and MexEF-OprN. In this review, the function, structure, and regulation of these efflux pumps in P. aeruginosa and their actions as resistance mechanisms are discussed. Finally, a brief discussion on the potential of efflux pumps in P. aeruginosa as a target for new drugs is presented.


Assuntos
Antibacterianos , Proteínas de Membrana Transportadoras , Proteínas de Membrana Transportadoras/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Pseudomonas aeruginosa/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/metabolismo
2.
Front Immunol ; 13: 867630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464433

RESUMO

Erythroferrone is a recently identified erythroid regulator produced by erythroblasts in the mammalian bone marrow and extramedullary sites, known to be induced in conditions of anemia or blood loss. Iron metabolism is affected by erythroferrone through its capacity to inhibit hepcidin production, leading to the increase of iron availability required for erythropoiesis. However, little is known about erythroferrone function in other vertebrates, in particular teleost fish, that unlike mammals, present two different functional types of hepcidin, one type mostly involved in iron metabolism and the other in antimicrobial response. The study of erythroferrone evolution and its biological role in teleost fish can give us valuably new insights into its function. To address these questions, we characterized erythroferrone in the European sea bass (Dicentrarchus labrax), a species presenting two hepcidin types, and evaluated variations in its expression levels in response to different experimental conditions. During experimental anemia, erythroferrone responds by increasing its expression and suppressing hepcidin production, following the pattern observed in mammals, but it is not influenced by iron overload. However, during bacterial infection, erythroferrone is downregulated and hepcidin levels increase. Furthermore, administration of Hamp1 but not of Hamp2 peptides suppresses erythroferrone expression. In conclusion, in dual hepcidin teleost fish erythroferrone seems to only interact with type 1 hepcidin, known to be involved in iron homeostasis, but not with type 2, which has an almost exclusive antimicrobial role.


Assuntos
Anemia , Anti-Infecciosos , Bass , Anemia/metabolismo , Animais , Anti-Infecciosos/metabolismo , Bass/microbiologia , Hepcidinas/metabolismo , Ferro/metabolismo , Mamíferos/metabolismo
3.
Front Immunol ; 12: 754437, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34646277

RESUMO

The current treatments applied in aquaculture to limit disease dissemination are mostly based on the use of antibiotics, either as prophylactic or therapeutic agents, with vaccines being available for a limited number of fish species and pathogens. Antimicrobial peptides are considered as promising novel substances to be used in aquaculture, due to their antimicrobial and immunomodulatory activities. Hepcidin, the major iron metabolism regulator, is found as a single gene in most mammals, but in certain fish species, including the European sea bass (Dicentrarchus labrax), two different hepcidin types are found, with specialized roles: the single type 1 hepcidin is involved in iron homeostasis trough the regulation of ferroportin, the only known iron exporter; and the various type 2 hepcidins present antimicrobial activity against a number of different pathogens. In this study, we tested the administration of sea bass derived hepcidins in models of infection and iron overload. Administration with hamp2 substantially reduced fish mortalities and bacterial loads, presenting itself as a viable alternative to the use of antibiotics. On the other hand, hamp1 seems to attenuate the effects of iron overload. Further studies are necessary to test the potential protective effects of hamp2 against other pathogens, as well as to understand how hamp2 stimulate the inflammatory responses, leading to an increased fish survival upon infection.


Assuntos
Peptídeos Antimicrobianos/uso terapêutico , Bass/imunologia , Doenças dos Peixes/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/veterinária , Hepcidinas/uso terapêutico , Sobrecarga de Ferro/veterinária , Photobacterium , Sequência de Aminoácidos , Animais , Apoferritinas/biossíntese , Apoferritinas/genética , Carga Bacteriana , Bass/microbiologia , Proteínas de Transporte de Cátions/biossíntese , Proteínas de Transporte de Cátions/genética , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Perfilação da Expressão Gênica , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/imunologia , Hepcidinas/biossíntese , Hepcidinas/genética , Ferro/análise , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/genética , Sobrecarga de Ferro/imunologia , Fígado/química , Photobacterium/isolamento & purificação
4.
Pharmaceuticals (Basel) ; 14(6)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198571

RESUMO

Beta-defensins consist in a group of cysteine-rich antimicrobial peptides (AMPs), widely found throughout vertebrate species, including teleost fish, with antimicrobial and immunomodulatory activities. However, although the European sea bass (Dicentrarchus labrax) is one of the most commercially important farmed fish species in the Mediterranean area, the characterization of its beta-defensins and its potential applications are still missing. In this study, we characterized two members of the beta-defensin family in this species. Phylogenetic and synteny analysis places sea bass peptides in the beta-defensin subfamilies 1 and 2, sharing similar features with the other members, including the six cysteines and the tertiary structure, that consists in three antiparallel beta-sheets, with beta-defensin 1 presenting an extra alpha-helix at the N-terminal. Further studies are necessary to uncover the functions of sea bass beta-defensins, particularly their antimicrobial and immunomodulatory properties, in order to develop novel prophylactic or therapeutic compounds to be used in aquaculture production.

5.
Haematologica ; 106(3): 806-818, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31919087

RESUMO

Trypanosomiasis is a parasitic disease affecting both humans and animals in the form of Human African Trypanosomiasis and Nagana disease, respectively. Anemia is one of the most common symptoms of trypanosomiasis, and if left unchecked can cause severe complications and even death. Several factors have been associated with the development of this anemia, including dysregulation of iron homeostasis, but little is known about the molecular mechanisms involved. Here, using murine models, we study the involvement of hepcidin, the key regulator of iron metabolism and an important player in the development of anemia of inflammation. Our data show two stages for the progression of anemia, to which hepcidin contributes a first stage when anemia develops, with a likely cytokine-mediated stimulation of hepcidin and subsequent limitation in iron availability and erythropoiesis, and a second stage of recovery, where the increase in hepcidin then declines due to the reduced inflammatory signal and increased production of erythroid regulators by the kidney, spleen and bone marrow, thus leading to an increase in iron release and availability, and enhanced erythropoiesis. In agreement with this, in hepcidin knockout mice, anemia is much milder and its recovery is complete, in contrast to wild-type animals which have not fully recovered from anemia after 21 days. Besides all other factors known to be involved in the development of anemia during trypanosomiasis, hepcidin clearly makes an important contribution to both its development and recovery.


Assuntos
Anemia , Trypanosoma brucei brucei , Anemia/etiologia , Animais , Eritropoese , Hepcidinas/genética , Ferro , Camundongos
6.
Rev. bras. ciênc. vet ; 27(4): 175-182, out./dez. 2020. graf, tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-1491687

RESUMO

Cardiopatias felinas apresentam importante relevância na rotina veterinária, todavia os seus aspectos epidemiológicos em gatos não são conhecidos regionalmente. O objetivo do estudo foi descrever a frequência das cardiopatias na região Norte e Vale do Itajaí no estado de Santa Catarina e determinar a sobrevida de pacientes cardiopatas e não cardiopatas. O estudo contou com a análise retrospectiva de 74 laudos ecocardiográficos e prontuários médicos de gatos oriundos de estabelecimentos veterinários da região, de janeiro de 2017 a dezembro de 2019. Tutores ou veterinários responsáveis foram contatados para averiguar a sobrevida dos animais. Os animais do estudo em sua maioria eram machos (n=40/74) e sem raça definida (n=47/74). Cardiomiopatia foi o diagnóstico mais comum (n=21/74), com destaque para o fenótipo hipertrófica (n=13/21). As cardiomiopatias foram diagnosticadas mais comumente em gatos acima de oito anos de idade. Os principais sinais clínicos nos gatos sintomáticos (n=41/74) foram sopro (n=15/41) e dispneia (n=6/41). Os principais achados ecocardiográficos foram hipertrofia concêntrica da parede livre do ventrículo esquerdo (n=18/41) e dilatação do átrio esquerdo (n=12/41). A mediana de sobrevida dos 74 gatos foi de 303±209.8 dias, estando altamente relacionado com a classe do estadiamento clínico (P=0,006). Gatos com fenótipo dilatada tiveram menor média de sobrevid


Feline cardiopathies are relevant on veterinary practice although lack of regional epidemiogical description. The purpose of this study is to determine cardiopathy prevalence and survival of cardiac and non-cardiac patients on Santa Catarina’s northern and Itajai valley regions. The retrospective study included 74 echocardiographic exams and medical records from January 2017 to December 2019. Veterinarians and owners were contacted to check survival on cardiac and non-cardiac patients. The animals were most male (n=40/74) and mongrel (n=47/74). Cardiomyopathies were the most common diagnosis (n=21/74), specially the hypertrophic phenotype (n=13/21). The cardiomyopathy diagnosis was evidenced in cats above eight years old. The most usual clinical findings on symptomatic patients (n=41/74) were cardiac murmur (n=15/41) and dyspnea (n=6/41). Left ventricular free wall concentric hypertrophy (n=18/41) and left atrium dilation (n=12/41) were the main echocardiographic findings. Median survival from 74 cats was 303±209,8 days and related to clinical staging (p=0,006). Cats with dilated cardiomyopathy phenotype presented lower mean survival (180,5 days). Concomitant diseases included chronic renal disease (n=7/15), systemic arterial hypertension (n=5/15) and/or hyperthyroidism (n=3/15). In conclusion, cats with cardiomyopathies, symptomatic and with more advanced stages of cardiac remodeling, have shown to live less than those in early stage of heart disease. As well as patients with associated concomitant diseases, they had a lower life expectancy.


Assuntos
Animais , Gatos , Cardiomiopatias/mortalidade , Cardiomiopatias/veterinária , Gatos/anormalidades , Gatos/crescimento & desenvolvimento , Análise de Sobrevida
7.
Rev. bras. ciênc. vet ; 27(4): 175-182, out./dez. 2020. il.
Artigo em Português | LILACS, VETINDEX | ID: biblio-1369506

RESUMO

Cardiopatias felinas apresentam importante relevância na rotina veterinária, todavia os seus aspectos epidemiológicos em gatos não são conhecidos regionalmente. O objetivo do estudo foi descrever a frequência das cardiopatias na região Norte e Vale do Itajaí no estado de Santa Catarina e determinar a sobrevida de pacientes cardiopatas e não cardiopatas. O estudo contou com a análise retrospectiva de 74 laudos ecocardiográficos e prontuários médicos de gatos oriundos de estabelecimentos veterinários da região, de janeiro de 2017 a dezembro de 2019. Tutores ou veterinários responsáveis foram contatados para averiguar a sobrevida dos animais. Os animais do estudo em sua maioria eram machos (n=40/74) e sem raça definida (n=47/74). Cardiomiopatia foi o diagnóstico mais comum (n=21/74), com destaque para o fenótipo hipertrófica (n=13/21). As cardiomiopatias foram diagnosticadas mais comumente em gatos acima de oito anos de idade. Os principais sinais clínicos nos gatos sintomáticos (n=41/74) foram sopro (n=15/41) e dispneia (n=6/41). Os principais achados ecocardiográficos foram hipertrofia concêntrica da parede livre do ventrículo esquerdo (n=18/41) e dilatação do átrio esquerdo (n=12/41). A mediana de sobrevida dos 74 gatos foi de 303±209.8 dias, estando altamente relacionado com a classe do estadiamento clínico (P=0,006). Gatos com fenótipo dilatada tiveram menor média de sobrevida (180.5 dias). As doenças concomitantes mais observadas foram doença renal crônica (n=7/15), hipertensão (n=5/15) e/ou hipertireoidismo (n=3/15). Gatos com cardiomiopatias, sintomáticos e com estágios mais avançados de remodelamento cardíaco, demostraram viver menos se comparados com aqueles em estágio inicial da cardiopatia. Bem como pacientes com doenças de base associada apresentaram menor expectativa de vida.


Feline cardiopathies are relevant on veterinary practice although lack of regional epidemiogical description. The purpose of this study is to determine cardiopathy prevalence and survival of cardiac and non-cardiac patients on Santa Catarina's northern and Itajai valley regions. The retrospective study included 74 echocardiographic exams and medical records from January 2017 to December 2019. Veterinarians and owners were contacted to check survival on cardiac and non-cardiac patients. The animals were most male (n=40/74) and mongrel (n=47/74). Cardiomyopathies were the most common diagnosis (n=21/74), specially the hypertrophic phenotype (n=13/21). The cardiomyopathy diagnosis was evidenced in cats above eight years old. The most usual clinical findings on symptomatic patients (n=41/74) were cardiac murmur (n=15/41) and dyspnea (n=6/41). Left ventricular free wall concentric hypertrophy (n=18/41) and left atrium dilation (n=12/41) were the main echocardiographic findings. Median survival from 74 cats was 303±209,8 days and related to clinical staging (p=0,006). Cats with dilated cardiomyopathy phenotype presented lower mean survival (180,5 days). Concomitant diseases included chronic renal disease (n=7/15), systemic arterial hypertension (n=5/15) and/or hyperthyroidism (n=3/15). In conclusion, cats with cardiomyopathies, symptomatic and with more advanced stages of cardiac remodeling, have shown to live less than those in early stage of heart disease. As well as patients with associated concomitant diseases, they had a lower life expectancy.


Assuntos
Animais , Gatos , Sobrevida/fisiologia , Ecocardiografia/veterinária , Gatos/fisiologia , Cardiopatias/veterinária , Cardiomiopatias/veterinária , Sintomas Concomitantes , Estudos Retrospectivos , Sopros Cardíacos/veterinária , Dispneia/veterinária
8.
Int J Mol Sci ; 21(13)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32610543

RESUMO

Fish rely on their innate immune responses to cope with the challenging aquatic environment, with antimicrobial peptides (AMPs) being one of the first line of defenses. Piscidins are a group of fish specific AMPs isolated in several species. However, in the European sea bass (Dicentrarchus labrax), the piscidin family remains poorly understood. We identified six different piscidins in sea bass, performed an in-depth molecular characterization and evaluated their antimicrobial activities against several bacterial and parasitic pathogens. Sea bass piscidins present variable amino acid sequences and antimicrobial activities, and can be divided in different sub groups: group 1, formed by piscidins 1 and 4; group 2, constituted by piscidins 2 and 5, and group 3, formed by piscidins 6 and 7. Additionally, we demonstrate that piscidins 1 to 5 possess a broad effect on multiple microorganisms, including mammalian parasites, while piscidins 6 and 7 have poor antibacterial and antiparasitic activities. These results raise questions on the functions of these peptides, particularly piscidins 6 and 7. Considering their limited antimicrobial activity, these piscidins might have other functional roles, but further studies are necessary to better understand what roles might those be.


Assuntos
Peptídeos Catiônicos Antimicrobianos/imunologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Bass/imunologia , Sequência de Aminoácidos/genética , Animais , Antibacterianos/metabolismo , Anti-Infecciosos/metabolismo , Peptídeos Catiônicos Antimicrobianos/química , Éxons/genética , Proteínas de Peixes/metabolismo , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Imunidade Inata/imunologia , Imunidade Inata/fisiologia , Filogenia , Splicing de RNA/genética
9.
ACS Chem Neurosci ; 10(9): 4076-4101, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31441641

RESUMO

Here, we present a series of dual-target phosphodiesterase 9 (PDE9) and histone deacetylase (HDAC) inhibitors devised as pharmacological tool compounds for assessing the implications of these two targets in Alzheimer's disease (AD). These novel inhibitors were designed taking into account the key pharmacophoric features of known selective PDE9 inhibitors as well as privileged chemical structures, bearing zinc binding groups (hydroxamic acids and ortho-amino anilides) that hit HDAC targets. These substituents were selected according to rational criteria and previous knowledge from our group to explore diverse HDAC selectivity profiles (pan-HDAC, HDAC6 selective, and class I selective) that were confirmed in biochemical screens. Their functional response in inducing acetylation of histone and tubulin and phosphorylation of cAMP response element binding (CREB) was measured as a requisite for further progression into complete in vitro absorption, distribution, metabolism and excretion (ADME) and in vivo brain penetration profiling. Compound 31b, a selective HDAC6 inhibitor with acceptable brain permeability, was chosen for assessing in vivo efficacy of these first-in-class inhibitors, as well as studying their mode of action (MoA).


Assuntos
3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , Doença de Alzheimer/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Ácidos Hidroxâmicos/metabolismo , Acetilação , Histona Desacetilases/química , Humanos , Ácidos Hidroxâmicos/química , Estrutura Molecular , Diester Fosfórico Hidrolases/metabolismo , Relação Estrutura-Atividade
10.
Front Aging Neurosci ; 11: 149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281249

RESUMO

The discouraging results with therapies for Alzheimer's disease (AD) in clinical trials, highlights the urgent need to adopt new approaches. Like other complex diseases, it is becoming clear that AD therapies should focus on the simultaneous modulation of several targets implicated in the disease. Recently, using reference compounds and the first-in class CM-414, we demonstrated that the simultaneous inhibition of histone deacetylases [class I histone deacetylases (HDACs) and HDAC6] and phosphodiesterase 5 (PDE5) has a synergistic therapeutic effect in AD models. To identify the best inhibitory balance of HDAC isoforms and PDEs that provides a safe and efficient therapy to combat AD, we tested the compound CM-695 in the Tg2576 mouse model of this disease. CM-695 selectively inhibits HDAC6 over class I HDAC isoforms, which largely overcomes the toxicity associated with HDAC class 1 inhibition. Furthermore, CM-695 inhibits PDE9, which is expressed strongly in the brain and has been proposed as a therapeutic target for AD. Chronic treatment of aged Tg2576 mice with CM-695 ameliorates memory impairment and diminishes brain Aß, although its therapeutic effect was no longer apparent 4 weeks after the treatment was interrupted. An increase in the presence of 78-KDa glucose regulated protein (GRP78) and heat shock protein 70 (Hsp70) chaperones may underlie the therapeutic effect of CM-695. In summary, chronic treatment with CM-695 appears to reverse the AD phenotype in a safe and effective manner. Taking into account that AD is a multifactorial disorder, the multimodal action of these compounds and the different events they affect may open new avenues to combat AD.

11.
ACS Chem Neurosci ; 10(3): 1765-1782, 2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30525452

RESUMO

In order to determine the contributions of histone deacetylase (HDAC) isoforms to the beneficial effects of dual phosphodiesterase 5 (PDE5) and pan-HDAC inhibitors on in vivo models of Alzheimer's disease (AD), we have designed, synthesized, and tested novel chemical probes with the desired target compound profile of PDE5 and class I HDAC selective inhibitors. Compared to previous hydroxamate-based series, these molecules exhibit longer residence times on HDACs. In this scenario, shorter or longer preincubation times may have a significant impact on the IC50 values of these compounds and therefore on their corresponding selectivity profiles on the different HDAC isoforms. On the other hand, different chemical series have been explored and, as expected, some pairwise comparisons show a clear impact of the scaffold on biological responses (e.g., 35a vs 40a). The lead identification process led to compound 29a, which shows an adequate ADME-Tox profile and in vivo target engagement (histone acetylation and cAMP/cGMP response element-binding (CREB) phosphorylation) in the central nervous system (CNS), suggesting that this compound represents an optimized chemical probe; thus, 29a has been assayed in a mouse model of AD (Tg2576).


Assuntos
Doença de Alzheimer/tratamento farmacológico , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Inibidores da Fosfodiesterase 5/farmacologia , Acetilação/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Inibidores de Histona Desacetilases/química , Histona Desacetilases/efeitos dos fármacos , Histona Desacetilases/metabolismo , Humanos , Camundongos , Inibidores da Fosfodiesterase 5/química
12.
Fish Shellfish Immunol ; 79: 209-217, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29775738

RESUMO

Many studies have assessed the effects of incorporation of plant feedstuffs in fish diets on growth performance, whereas few studies have addressed the effects of fish meal replacement by plant protein sources on fish immune parameters. Thus, the aim of this study was to evaluate the effects on immune response of different inclusion levels of carob seed germ meal (CSGM) as partial replacement for fish meal in diets for meagre (Argyrosomus regius) juveniles. Fish were fed four experimental diets with increased CSGM inclusion levels [0% (control), 7.5% (CSGM7.5), 15% (CSGM15) and 22.5% (CSGM22.5)]. After 1, 2, and 8 weeks of feeding fish were sampled to determine haematological profile and several humoral parameters in plasma and intestine. Results showed that dietary inclusion of CSGM did not negatively affect the immune parameters of meagre. In addition, total numbers of red and white blood cells, as well as thrombocytes, lymphocytes, monocytes, and neutrophils counts were not affected by dietary treatments. All parameters evaluated in plasma were unaffected by dietary CSGM inclusion after 1 and 2 weeks of feeding, with only the haemolytic complement activity showing an increase in fish fed diets with CSGM after 1 week and in fish fed CSGM22.5 diet after 2 weeks. Regarding the innate immune parameters analysed in the intestine, it could be highlighted the increase in alkaline phosphatase and antiprotease activities in fish fed the diet with the higher inclusion of CSGM at 8 weeks. Overall, results suggest that high dietary CSGM inclusion do not compromise immune status or induce an inflammatory response in meagre juveniles.


Assuntos
Fabaceae/química , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Perciformes/lesões , Ração Animal/análise , Animais , Dieta/veterinária , Relação Dose-Resposta a Droga , Intestinos/imunologia , Sementes/química
13.
Eur J Med Chem ; 150: 506-524, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29549837

RESUMO

We have identified chemical probes that act as dual phosphodiesterase 5 (PDE5) and histone deacetylase 6 (HDAC6)-selective inhibitors (>1 log unit difference versus class I HDACs) to decipher the contribution of HDAC isoforms to the positive impact of dual-acting PDE5 and HDAC inhibitors on mouse models of Alzheimer's disease (AD) and fine-tune this systems therapeutics approach. Structure- and knowledge-based approaches led to the design of first-in-class molecules with the desired target compound profile: dual PDE5 and HDAC6-selective inhibitors. Compound 44b, which fulfilled the biochemical, functional and ADME-Tox profiling requirements and exhibited adequate pharmacokinetic properties, was selected as pharmacological tool compound and tested in a mouse model of AD (Tg2576) in vivo.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Desenho de Fármacos , Desacetilase 6 de Histona/antagonistas & inibidores , Inibidores de Histona Desacetilases/farmacologia , Inibidores da Fosfodiesterase 5/farmacologia , Doença de Alzheimer/metabolismo , Linhagem Celular , Relação Dose-Resposta a Droga , Desacetilase 6 de Histona/metabolismo , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/química , Humanos , Estrutura Molecular , Neuroglia/efeitos dos fármacos , Inibidores da Fosfodiesterase 5/síntese química , Inibidores da Fosfodiesterase 5/química , Relação Estrutura-Atividade
14.
Neuropsychopharmacology ; 42(2): 524-539, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27550730

RESUMO

The targeting of two independent but synergistic enzymatic activities, histone deacetylases (HDACs, class I and HDAC6) and phosphodiesterase 5 (PDE5), has recently been validated as a potentially novel therapeutic approach for Alzheimer's disease (AD). Here we report the discovery of a new first-in-class small-molecule (CM-414) that acts as a dual inhibitor of PDE5 and HDACs. We have used this compound as a chemical probe to validate this systems therapeutics strategy, where an increase in the activation of cAMP/cGMP-responsive element-binding protein (CREB) induced by PDE5 inhibition, combined with moderate HDAC class I inhibition, leads to efficient histone acetylation. This molecule rescued the impaired long-term potentiation evident in hippocampal slices from APP/PS1 mice. Chronic treatment of Tg2576 mice with CM-414 diminished brain Aß and tau phosphorylation (pTau) levels, increased the inactive form of GSK3ß, reverted the decrease in dendritic spine density on hippocampal neurons, and reversed their cognitive deficits, at least in part by inducing the expression of genes related to synaptic transmission. Thus, CM-414 may serve as the starting point to discover balanced dual inhibitors with an optimal efficacy and safety profile for clinical testing on AD patients.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Inibidores de Histona Desacetilases/administração & dosagem , Plasticidade Neuronal/efeitos dos fármacos , Inibidores da Fosfodiesterase 5/administração & dosagem , Pirazóis/uso terapêutico , Pirimidinonas/uso terapêutico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/prevenção & controle , Animais , Comportamento Animal/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Hipocampo/fisiopatologia , Inibidores de Histona Desacetilases/farmacologia , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Inibidores da Fosfodiesterase 5/farmacologia , Cultura Primária de Células , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Pirimidinonas/administração & dosagem , Pirimidinonas/farmacologia
15.
J Med Chem ; 59(19): 8967-9004, 2016 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-27606546

RESUMO

Simultaneous inhibition of phosphodiesterase 5 (PDE5) and histone deacetylases (HDAC) has recently been validated as a potentially novel therapeutic approach for Alzheimer's disease (AD). To further extend this concept, we designed and synthesized the first chemical series of dual acting PDE5 and HDAC inhibitors, and we validated this systems therapeutics approach. Following the implementation of structure- and knowledge-based approaches, initial hits were designed and were shown to validate our hypothesis of dual in vitro inhibition. Then, an optimization strategy was pursued to obtain a proper tool compound for in vivo testing in AD models. Initial hits were translated into molecules with adequate cellular functional responses (histone acetylation and cAMP/cGMP response element-binding (CREB) phosphorylation in the nanomolar range), an acceptable therapeutic window (>1 log unit), and the ability to cross the blood-brain barrier, leading to the identification of 7 as a candidate for in vivo proof-of-concept testing ( Cuadrado-Tejedor, M.; Garcia-Barroso, C.; Sánchez-Arias, J. A.; Rabal, O.; Mederos, S.; Ugarte, A.; Franco, R.; Segura, V.; Perea, G.; Oyarzabal, J.; Garcia-Osta, A. Neuropsychopharmacology 2016 , in press, doi: 10.1038/npp.2016.163 ).


Assuntos
Inibidores de Histona Desacetilases/química , Inibidores de Histona Desacetilases/farmacologia , Inibidores da Fosfodiesterase 5/química , Inibidores da Fosfodiesterase 5/farmacologia , Acetilação/efeitos dos fármacos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Desenho de Fármacos , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/farmacocinética , Histona Desacetilases/metabolismo , Humanos , Camundongos , Modelos Moleculares , Inibidores da Fosfodiesterase 5/síntese química , Inibidores da Fosfodiesterase 5/farmacocinética
16.
J Neurochem ; 136(2): 403-15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26641206

RESUMO

Sildenafil (Viagra) is a selective inhibitor of phosphodiesterase type 5 (PDE5), which degrades cyclic guanosine monophosphate to the linear nucleotide. Sildenafil is acutely used in erectile dysfunction and chronically in pulmonary hypertension. Evidence in the last decade shows that sildenafil may have potential as a therapeutic option for Alzheimer's disease or other neurodegenerative disorders. The purpose of this work was to explore whether sildenafil crosses the blood-brain barrier. Pharmacokinetic properties of sildenafil in rodents were investigated using (11) C-radiolabeling followed by in vivo positron emission tomography (PET) and ex vivo tissue dissection and gamma counting. PET results in rats suggest penetration into the central nervous system. Ex vivo data in perfused animals suggest that trapping of [(11) C]sildenafil within the cerebral vascular endothelium limits accumulation in the central nervous system parenchyma. Peroral sildenafil administration to Macaca fascicularis and subsequent chemical analysis of plasma and cerebrospinal fluid (CSF) using liquid chromatography coupled with tandem mass spectrometry showed that drug content in the CSF was high enough to achieve PDE5 inhibition, which was also demonstrated by the significant increases in CSF cyclic guanosine monophosphate levels. Central actions of sildenafil include both relaxation of the cerebral vasculature and inhibition of PDE5 in neurons and glia. This central action of sildenafil may underlie its efficacy in neuroprotection models, and may justify the continued search for a PDE5 ligand suitable for PET imaging. Sildenafil interacts with phosphodiesterase type 5 (PDE5) expressed in the endothelium and/or smooth muscle cells of brain vessels and also crosses the blood-brain barrier to interact with PDE5 expressed in brain cells. At therapeutic doses, the concentration of sildenafil in the cerebrospinal fluid (CSF) is high enough to inhibit PDE5 in the neural cells (neurons and glia). In turn, the concentration of cGMP likely increases in parenchymal cells and, as shown in this report, in the CSF. Read the Editorial Highlight for this article on page 220. Cover Image for this issue: doi: 10.1111/jnc.13302.


Assuntos
GMP Cíclico/líquido cefalorraquidiano , Inibidores da Fosfodiesterase 5/farmacocinética , Citrato de Sildenafila/farmacocinética , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Cromatografia Líquida , GMP Cíclico/sangue , Rim/diagnóstico por imagem , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Macaca fascicularis , Masculino , Tomografia por Emissão de Pósitrons , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem , Testículo/efeitos dos fármacos , Testículo/metabolismo , Fatores de Tempo , Distribuição Tecidual/efeitos dos fármacos , Tomógrafos Computadorizados
17.
Rev. Bras. Odontol. Leg. RBOL ; 3(2): 92-104, 2016. ilus, tab
Artigo em Português | LILACS | ID: biblio-831256

RESUMO

A perícia odontológica trabalhista é uma das áreas de atuação do especialista em odontologia legal e origor na execução do exame pericial nesta área se faz necessário no sentido de analisar o tipo de trauma que atingiu o trabalhador, identificar e valorar os danos corporais e estabelecer o nexo de causalidade, subsidiando o magistrado com os elementos técnicos necessários para a sua decisão. O presente trabalho relata um caso pericial trabalhista relacionado a um trabalhador que utilizava veículos automotores em sua prática laboral, em que ocorreu acidente de trabalho, havendo nexo causal e danos odontológicos, sendo que não houve condenação da empresa reclamada para indenizar seu empregado pelos danos sofridos, uma vez que foi caracterizada culpa exclusiva do trabalhador. Conclui-se que aprova pericial odontológica, mesmo que conclusiva, constitui um dos meios de prova para a apreciação judicial, não implicando, necessariamente, em peça única para configurar eventual procedência em açõesde reparação de danos causados em âmbito trabalhista.


The labor dental expertise is one of the areas of specialist in forensic dentistry, and the rigor in the execution of forensic dental exam in this area to: analyze the type of trauma that hit the worker, identify and value the injury and establish the cause-effect relation, subsidize the magistrate with the technical elements necessary for its decision. This paper reports a labor expert in which case even if there is link between dental damage presented by the employee, resulting from work accident, there was nocondemnation of the defendant company to indemnify its employee for damages, since it was featuredexclusive fault of the worker. We conclude that the dental expert evidence, even if conclusive, is one of theevidence for judicial review, not implying necessarily in one piece to set any precedence in damage repairactions caused in labor sphere.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Legislação Trabalhista , Odontologia Legal/métodos , Traumatismos Dentários/complicações , Traumatismos Dentários/diagnóstico
18.
Medicina (Ribeiräo Preto) ; 48(1): 65-76, jan.-fev. 2015.
Artigo em Português | LILACS | ID: lil-750145

RESUMO

O objetivo deste estudo foi propor uma lista de indicadores como forma de avaliação de desempenho para o Centro de Engenharia Clínica e Bioequipamentos do HCFMRP-USP. Indicadores são importantes ferramentas de controle e de qualidade e fornecem bases para melhorar o desempenho do estabelecimento de saúde. Para a coleta de dados, foi utilizada a literatura, referente aos indicadores para a área de Engenharia Clínica. Equipe multidisciplinar composta pelos autores do artigo foi formada para discutir e escolher os indicadores que seriam propostos como medidas de avaliação de desempenho. Foi desenvolvido um estudo na bibliografia disponível sobre o tema e também entrevistas com os gestores-chaves que estão responsáveis pela área. Adotou-se o BSC - Balanced Scorecard, em suas perspectivas financeira, de clientes, de processos internos e de aprendizado e crescimento como mapa estruturante dos indicadores. Foram propostos dezesseis indicadores nas quatro perspectivas do BSC...


The aim of this study was to propose a list of indicators as a mean of performance evaluation for the Clinical Engineering Center of the Hospital of Pharmaceutical Sciences and Medicine of Ribeirão Preto (HCFMRP – USP). Indicators are important tools of quality control and supply bases to enhance the performance of the health facility. In order to collect data, it was used the literature regarding the indicators for the area of Clinical Engineering. Multidisciplinary team was formed to discuss and choose the indicators that were proposed as measures of performance evaluation. A study in the literature available about the topic and also interviews with the key managers who are responsible for the area were developed. It was adopted the BSC - Balanced Scorecard as a structural map of the indicators. Sixteen indicators were proposed in the four BSC...


Assuntos
Humanos , Administração Hospitalar , Engenharia Biomédica , Indicadores de Gestão , Planejamento Estratégico
19.
Neuropathol Appl Neurobiol ; 41(4): 471-82, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25488891

RESUMO

AIMS: Levels of the cyclic nucleotides guanosine 3', 5'-monophosphate (cGMP) or adenosine 3', 5'-monophosphate (cAMP) that play important roles in memory processes are not characterized in Alzheimer's disease (AD). The aim of this study was to analyse the levels of these nucleotides in cerebrospinal fluid (CSF) samples from patients diagnosed with clinical and prodromal stages of AD and study the expression level of the enzymes that hydrolyzed them [phosphodiesterases (PDEs)] in the brain of AD patients vs. METHODS: For cGMP and cAMP CSF analysis, the cohort (n = 79) included cognitively normal participants (subjective cognitive impairment), individuals with stable mild cognitive impairment or AD converters (sMCI and cMCI), and mild AD patients. A high throughput liquid chromatography-tandem mass spectrometry method was used. Interactions between CSF cGMP or cAMP with mini-mental state examination (MMSE) score, CSF Aß(1-42) and CSF p-tau were analysed. For PDE4, 5, 9 and 10 expression analysis, brains of AD patients vs. controls (n = 7 and n = 8) were used. RESULTS: cGMP, and not cAMP levels, were significantly lower in the CSF of patients diagnosed with mild AD when compared with nondemented controls. CSF levels of cGMP showed a significant association with MMSE-diagnosed clinical dementia and with CSF biomarker Aß42 in AD patients. Significant increase in PDE5 expression was detected in temporal cortex of AD patients compared with that of age-matched healthy control subjects. No changes in the expression of others PDEs were detected. CONCLUSIONS: These results support the potential involvement of cGMP in the pathological and clinical development of AD. The cGMP reduction in early stages of AD might participate in the aggravation of amyloid pathology and cognitive decline.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , GMP Cíclico/líquido cefalorraquidiano , Idoso , Doença de Alzheimer/enzimologia , Doença de Alzheimer/patologia , Encéfalo/enzimologia , Encéfalo/patologia , Disfunção Cognitiva/líquido cefalorraquidiano , Disfunção Cognitiva/enzimologia , Disfunção Cognitiva/patologia , AMP Cíclico/líquido cefalorraquidiano , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Diester Fosfórico Hidrolases
20.
J Alzheimers Dis ; 42 Suppl 4: S561-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25125473

RESUMO

Understanding the cellular and molecular processes involved in learning and memory will help in the development of safe and effective cognitive enhancers. The cAMP response element-binding (CREB) may be a universal modulator of processes required for memory formation, and increasing the levels of second messengers like cAMP and cGMP could ultimately lead to CREB activation. Phosphodiesterase (PDE) inhibitors regulate signaling pathways by elevating cAMP and/or cGMP levels, and they have been demonstrated to improve learning and memory in a number of rodent models of impaired cognition. The aim of this review is to summarize the outstanding progress that has been made in the application of PDE inhibitors for memory dysfunction. In addition, we have introduced some recent data we generated demonstrating that tadalafil could be considered as an optimal candidate for drug re-positioning and as a good candidate to enhance cognition.


Assuntos
Transtornos Cognitivos/tratamento farmacológico , Transtornos Cognitivos/enzimologia , Inibidores de Fosfodiesterase/uso terapêutico , Diester Fosfórico Hidrolases/metabolismo , Animais , Humanos
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