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1.
J Biol Chem ; 300(3): 105700, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38307383

RESUMO

Selective retrograde transport from endosomes back to the trans-Golgi network (TGN) is important for maintaining protein homeostasis, recycling receptors, and returning molecules that were transported to the wrong compartments. Two important transmembrane proteins directed to this pathway are the Cation-Independent Mannose-6-phosphate receptor (CI-MPR) and the ATP7B copper transporter. Among CI-MPR functions is the delivery of acid hydrolases to lysosomes, while ATP7B facilitates the transport of cytosolic copper ions into organelles or the extracellular space. Precise subcellular localization of CI-MPR and ATP7B is essential for the proper functioning of these proteins. This study shows that both CI-MPR and ATP7B interact with a variant of the clathrin adaptor 1 (AP-1) complex that contains a specific isoform of the γ-adaptin subunit called γ2. Through synchronized anterograde trafficking and cell-surface uptake assays, we demonstrated that AP-1γ2 is dispensable for ATP7B and CI-MPR exit from the TGN while being critically required for ATP7B and CI-MPR retrieval from endosomes to the TGN. Moreover, AP-1γ2 depletion leads to the retention of endocytosed CI-MPR in endosomes enriched in retromer complex subunits. These data underscore the importance of AP-1γ2 as a key component in the sorting and trafficking machinery of CI-MPR and ATP7B, highlighting its essential role in the transport of proteins from endosomes.


Assuntos
Complexo 1 de Proteínas Adaptadoras , ATPases Transportadoras de Cobre , Endossomos , Transporte Proteico , Receptor IGF Tipo 2 , Rede trans-Golgi , Humanos , Endossomos/metabolismo , Células HeLa , Transporte Proteico/genética , Receptor IGF Tipo 2/genética , Receptor IGF Tipo 2/metabolismo , Rede trans-Golgi/genética , Rede trans-Golgi/metabolismo , ATPases Transportadoras de Cobre/genética , ATPases Transportadoras de Cobre/metabolismo , Complexo 1 de Proteínas Adaptadoras/genética , Complexo 1 de Proteínas Adaptadoras/metabolismo , Subunidades gama do Complexo de Proteínas Adaptadoras/metabolismo
2.
Biochim Biophys Acta Mol Basis Dis ; 1870(2): 166980, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38061599

RESUMO

Disruption of brain cholesterol homeostasis has been implicated in neurodegeneration. Nevertheless, the role of cholesterol in Parkinson's Disease (PD) remains unclear. We have used N2a mouse neuroblastoma cells and primary cultures of mouse neurons and 1-methyl-4-phenylpyridinium (MPP+), a known mitochondrial complex I inhibitor and the toxic metabolite of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), known to trigger a cascade of events associated with PD neuropathological features. Simultaneously, we utilized other mitochondrial toxins, including antimycin A, oligomycin, and carbonyl cyanide chlorophenylhydrazone. MPP+ treatment resulted in elevated levels of total cholesterol and in a Niemann Pick type C1 (NPC1)-like phenotype characterized by accumulation of cholesterol in lysosomes. Interestingly, NPC1 mRNA levels were specifically reduced by MPP+. The decrease in NPC1 levels was also seen in midbrain and striatum from MPTP-treated mice and in primary cultures of neurons treated with MPP+. Together with the MPP+-dependent increase in intracellular cholesterol levels in N2a cells, we observed an increase in 5' adenosine monophosphate-activated protein kinase (AMPK) phosphorylation and a concomitant increase in the phosphorylated levels of mammalian target of rapamycin (mTOR). NPC1 knockout delayed cell death induced by acute mitochondrial damage, suggesting that transient cholesterol accumulation in lysosomes could be a protective mechanism against MPTP/MPP+ insult. Interestingly, we observed a negative correlation between NPC1 protein levels and disease stage, in human PD brain samples. In summary, MPP+ decreases NPC1 levels, elevates lysosomal cholesterol accumulation and alters mTOR signaling, adding to the existing notion that PD may rise from alterations in mitochondrial-lysosomal communication.


Assuntos
Doença de Parkinson , Animais , Humanos , Camundongos , Colesterol/metabolismo , Mamíferos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteína C1 de Niemann-Pick , Fenótipo , Serina-Treonina Quinases TOR/metabolismo
3.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 166993, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38142760

RESUMO

Cholesterol 24-hydroxylase (CYP46A1) is an exclusively neuronal cytochrome P450 enzyme responsible for converting cholesterol into 24S-hydroxycholesterol, which serves as the primary pathway for eliminating cholesterol in the brain. We and others have shown that increased activity of CYP46A1 leads to reduced levels of cholesterol and has a positive effect on cognition. Therefore, we hypothesized that CYP46A1 could be a potential therapeutic target in Niemann-Pick type C (NPC) disease, a rare and fatal neurodegenerative disorder, characterized by cholesterol accumulation in endolysosomal compartments. Herein, we show that CYP46A1 ectopic expression, in cellular models of NPC and in Npc1tm(I1061T) mice by adeno-associated virus-mediated gene therapy improved NPC disease phenotype. Amelioration in functional, biochemical, molecular and neuropathological hallmarks of NPC disease were characterized. In vivo, CYP46A1 expression partially prevented weight loss and hepatomegaly, corrected the expression levels of genes involved in cholesterol homeostasis, and promoted a redistribution of brain cholesterol accumulated in late endosomes/lysosomes. Moreover, concomitant with the amelioration of cholesterol metabolism dysregulation, CYP46A1 attenuated microgliosis and lysosomal dysfunction in mouse cerebellum, favoring a pro-resolving phenotype. In vivo CYP46A1 ectopic expression improves important features of NPC disease and may represent a valid therapeutic approach to be used concomitantly with other drugs. However, promoting cholesterol redistribution does not appear to be enough to prevent Purkinje neuronal death in the cerebellum. This indicates that cholesterol buildup in neurons might not be the main cause of neurodegeneration in this human lipidosis.


Assuntos
Doença de Niemann-Pick Tipo C , Camundongos , Humanos , Animais , Doença de Niemann-Pick Tipo C/genética , Doença de Niemann-Pick Tipo C/terapia , Doença de Niemann-Pick Tipo C/metabolismo , Colesterol 24-Hidroxilase/metabolismo , Colesterol 24-Hidroxilase/uso terapêutico , Colesterol/metabolismo , Encéfalo/metabolismo , Cerebelo/patologia
4.
Pharmaceuticals (Basel) ; 16(8)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37631011

RESUMO

Cancer is a complex multifactorial disease whose pathophysiology involves multiple metabolic pathways, including the ubiquitin-proteasome system, for which several proteasome inhibitors have already been approved for clinical use. However, the resistance to existing therapies and the occurrence of severe adverse effects is still a concern. The purpose of this study was the discovery of novel scaffolds of proteasome inhibitors with anticancer activity, aiming to overcome the limitations of the existing proteasome inhibitors. Thus, a structure-based virtual screening protocol was developed using the structure of the human 20S proteasome, and 246 compounds from virtual databases were selected for in vitro evaluation, namely proteasome inhibition assays and cell viability assays. Compound 4 (JHG58) was shortlisted as the best hit compound based on its potential in terms of proteasome inhibitory activity and its ability to induce cell death (both with IC50 values in the low micromolar range). Molecular docking studies revealed that compound 4 interacts with key residues, namely with the catalytic Thr1, Ala20, Thr21, Lys33, and Asp125 at the chymotrypsin-like catalytic active site. The hit compound is a good candidate for additional optimization through a hit-to-lead campaign.

5.
J Pediatr Genet ; 12(3): 258-262, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37575650

RESUMO

X-linked myotubular myopathy (XLMTM), a centronuclear congenital myopathy secondary to pathogenic variants in the MTM1 gene encoding myotubularin, is typically recognized for its classic and severe phenotype which includes neonatal hypotonia, severe muscle weakness, long-term ventilator dependence, markedly delayed gross motor milestones with inability to independently ambulate, and a high neonatal and childhood mortality. However, milder congenital forms of the condition and other phenotypes are recognized. We describe a 6-year-old boy with a mild XLMTM phenotype with independent gait and no respiratory insufficiency even in the neonatal period. The child has a hemizygous novel splice site variant in the MTM1 gene (c.232-25A > T) whose pathogenicity was confirmed by cDNA studies (exon 5 skipping) and muscle biopsy findings. We also compared the phenotype of our patient with the few reported cases that presented a mild XLMTM phenotype and no respiratory distress at birth, and discussed the potential mechanisms underlying this phenotype such as the presence of residual expression of the normal myotubularin transcript.

6.
Tomazini, Bruno M; Nassar Jr, Antonio Paulo; Lisboa, Thiago Costa; Azevedo, Luciano César Pontes de; Veiga, Viviane Cordeiro; Catarino, Daniela Ghidetti Mangas; Fogazzi, Debora Vacaro; Arns, Beatriz; Piastrelli, Filipe Teixeira; Dietrich, Camila; Negrelli, Karina Leal; Jesuíno, Isabella de Andrade; Reis, Luiz Fernando Lima; Mattos, Renata Rodrigues de; Pinheiro, Carla Cristina Gomes; Luz, Mariane Nascimento; Spadoni, Clayse Carla da Silva; Moro, Elisângela Emilene; Bueno, Flávia Regina; Sampaio, Camila Santana Justo Cintra; Silva, Débora Patrício; Baldassare, Franca Pellison; Silva, Ana Cecilia Alcantara; Veiga, Thabata; Barbante, Leticia; Lambauer, Marianne; Campos, Viviane Bezerra; Santos, Elton; Santos, Renato Hideo Nakawaga; Laranjeiras, Ligia Nasi; Valeis, Nanci; Santucci, Eliana; Miranda, Tamiris Abait; Patrocínio, Ana Cristina Lagoeiro do; Carvalho, Andréa de; Sousa, Eduvirgens Maria Couto de; Sousa, Ancelmo Honorato Ferraz de; Malheiro, Daniel Tavares; Bezerra, Isabella Lott; Rodrigues, Mirian Batista; Malicia, Julliana Chicuta; Silva, Sabrina Souza da; Gimenes, Bruna dos Passos; Sesin, Guilhermo Prates; Zavascki, Alexandre Prehn; Sganzerla, Daniel; Medeiros, Gregory Saraiva; Santos, Rosa da Rosa Minho dos; Silva, Fernanda Kelly Romeiro; Cheno, Maysa Yukari; Abrahão, Carolinne Ferreira; Oliveira Junior, Haliton Alves de; Rocha, Leonardo Lima; Nunes Neto, Pedro Aniceto; Pereira, Valéria Chagas; Paciência, Luis Eduardo Miranda; Bueno, Elaine Silva; Caser, Eliana Bernadete; Ribeiro, Larissa Zuqui; Fernandes, Caio Cesar Ferreira; Garcia, Juliana Mazzei; Silva, Vanildes de Fátima Fernandes; Santos, Alisson Junior dos; Machado, Flávia Ribeiro; Souza, Maria Aparecida de; Ferronato, Bianca Ramos; Urbano, Hugo Corrêa de Andrade; Moreira, Danielle Conceição Aparecida; Souza-Dantas, Vicente Cés de; Duarte, Diego Meireles; Coelho, Juliana; Figueiredo, Rodrigo Cruvinel; Foreque, Fernanda; Romano, Thiago Gomes; Cubos, Daniel; Spirale, Vladimir Miguel; Nogueira, Roberta Schiavon; Maia, Israel Silva; Zandonai, Cassio Luis; Lovato, Wilson José; Cerantola, Rodrigo Barbosa; Toledo, Tatiana Gozzi Pancev; Tomba, Pablo Oscar; Almeida, Joyce Ramos de; Sanches, Luciana Coelho; Pierini, Leticia; Cunha, Mariana; Sousa, Michelle Tereza; Azevedo, Bruna; Dal-Pizzol, Felipe; Damasio, Danusa de Castro; Bainy, Marina Peres; Beduhn, Dagoberta Alves Vieira; Jatobá, Joana DArc Vila Nova; Moura, Maria Tereza Farias de; Rego, Leila Rezegue de Moraes; Silva, Adria Vanessa da; Oliveira, Luana Pontes; Sodré Filho, Eliene Sá; Santos, Silvana Soares dos; Neves, Itallo de Lima; Leão, Vanessa Cristina de Aquino; Paes, João Lucidio Lobato; Silva, Marielle Cristina Mendes; Oliveira, Cláudio Dornas de; Santiago, Raquel Caldeira Brant; Paranhos, Jorge Luiz da Rocha; Wiermann, Iany Grinezia da Silva; Pedroso, Durval Ferreira Fonseca; Sawada, Priscilla Yoshiko; Prestes, Rejane Martins; Nascimento, Glícia Cardoso; Grion, Cintia Magalhães Carvalho; Carrilho, Claudia Maria Dantas de Maio; Dantas, Roberta Lacerda Almeida de Miranda; Silva, Eliane Pereira; Silva, Antônio Carlos da; Oliveira, Sheila Mara Bezerra de; Golin, Nicole Alberti; Tregnago, Rogerio; Lima, Valéria Paes; Silva, Kamilla Grasielle Nunes da; Boschi, Emerson; Buffon, Viviane; Machado, André SantAna; Capeletti, Leticia; Foernges, Rafael Botelho; Carvalho, Andréia Schubert de; Oliveira Junior, Lúcio Couto de; Oliveira, Daniela Cunha de; Silva, Everton Macêdo; Ribeiro, Julival; Pereira, Francielle Constantino; Salgado, Fernanda Borges; Deutschendorf, Caroline; Silva, Cristofer Farias da; Gobatto, Andre Luiz Nunes; Oliveira, Carolaine Bomfim de; Dracoulakis, Marianna Deway Andrade; Alvaia, Natália Oliveira Santos; Souza, Roberta Machado de; Araújo, Larissa Liz Cardoso de; Melo, Rodrigo Morel Vieira de; Passos, Luiz Carlos Santana; Vidal, Claudia Fernanda de Lacerda; Rodrigues, Fernanda Lopes de Albuquerque; Kurtz, Pedro; Shinotsuka, Cássia Righy; Tavares, Maria Brandão; Santana, Igor das Virgens; Gavinho, Luciana Macedo da Silva; Nascimento, Alaís Brito; Pereira, Adriano J; Cavalcanti, Alexandre Biasi.
Rev. bras. ter. intensiva ; 34(4): 418-425, out.-dez. 2022. tab, graf
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1423667

RESUMO

RESUMO Objetivo: Descrever o IMPACTO-MR, um estudo brasileiro de plataforma nacional em unidades de terapia intensiva focado no impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Métodos: Descrevemos a plataforma IMPACTO-MR, seu desenvolvimento, critérios para seleção das unidades de terapia intensiva, caracterização da coleta de dados, objetivos e projetos de pesquisa futuros a serem realizados na plataforma. Resultados: Os dados principais foram coletados por meio do Epimed Monitor System® e consistiram em dados demográficos, dados de comorbidades, estado funcional, escores clínicos, diagnóstico de internação e diagnósticos secundários, dados laboratoriais, clínicos e microbiológicos e suporte de órgãos durante a internação na unidade de terapia intensiva, entre outros. De outubro de 2019 a dezembro de 2020, 33.983 pacientes de 51 unidades de terapia intensiva foram incluídos no banco de dados principal. Conclusão: A plataforma IMPACTO-MR é um banco de dados clínico brasileiro de unidades de terapia intensiva focado na pesquisa do impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Essa plataforma fornece dados para o desenvolvimento e pesquisa de unidades de terapia intensiva individuais e ensaios clínicos observacionais e prospectivos multicêntricos.


ABSTRACT Objective: To describe the IMPACTO-MR, a Brazilian nationwide intensive care unit platform study focused on the impact of health care-associated infections due to multidrug-resistant bacteria. Methods: We described the IMPACTO-MR platform, its development, criteria for intensive care unit selection, characterization of core data collection, objectives, and future research projects to be held within the platform. Results: The core data were collected using the Epimed Monitor System® and consisted of demographic data, comorbidity data, functional status, clinical scores, admission diagnosis and secondary diagnoses, laboratory, clinical, and microbiological data, and organ support during intensive care unit stay, among others. From October 2019 to December 2020, 33,983 patients from 51 intensive care units were included in the core database. Conclusion: The IMPACTO-MR platform is a nationwide Brazilian intensive care unit clinical database focused on researching the impact of health care-associated infections due to multidrug-resistant bacteria. This platform provides data for individual intensive care unit development and research and multicenter observational and prospective trials.

7.
Molecules ; 27(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408601

RESUMO

Proteasome inhibitors have shown relevant clinical activity in several hematological malignancies, namely in multiple myeloma and mantle cell lymphoma, improving patient outcomes such as survival and quality of life, when compared with other therapies. However, initial response to the therapy is a challenge as most patients show an innate resistance to proteasome inhibitors, and those that respond to the therapy usually develop late relapses suggesting the development of acquired resistance. The mechanisms of resistance to proteasome inhibition are still controversial and scarce in the literature. In this review, we discuss the development of proteasome inhibitors and the mechanisms of innate and acquired resistance to their activity-a major challenge in preclinical and clinical therapeutics. An improved understanding of these mechanisms is crucial to guiding the design of new and more effective drugs to tackle these devastating diseases. In addition, we provide a comprehensive overview of proteasome inhibitors used in combination with other chemotherapeutic agents, as this is a key strategy to combat resistance.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Neoplasias , Adulto , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Bortezomib/farmacologia , Bortezomib/uso terapêutico , Humanos , Mieloma Múltiplo/tratamento farmacológico , Neoplasias/tratamento farmacológico , Complexo de Endopeptidases do Proteassoma , Inibidores de Proteassoma/farmacologia , Inibidores de Proteassoma/uso terapêutico , Qualidade de Vida
8.
Biomedicines ; 9(12)2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34944570

RESUMO

The low regeneration potential of the central nervous system (CNS) represents a challenge for the development of new therapeutic strategies for neurodegenerative diseases, including spinocerebellar ataxias. Spinocerebellar ataxia type 3 (SCA3)-or Machado-Joseph disease (MJD)-is the most common dominant ataxia, being mainly characterized by motor deficits; however, SCA3/MJD has a complex and heterogeneous pathophysiology, involving many CNS brain regions, contributing to the lack of effective therapies. Mesenchymal stem cells (MSCs) have been proposed as a potential therapeutic tool for CNS disorders. Beyond their differentiation potential, MSCs secrete a broad range of neuroregulatory factors that can promote relevant neuroprotective and immunomodulatory actions in different pathophysiological contexts. The objective of this work was to study the effects of (1) human MSC transplantation and (2) human MSC secretome (CM) administration on disease progression in vivo, using the CMVMJD135 mouse model of SCA3/MJD. Our results showed that a single CM administration was more beneficial than MSC transplantation-particularly in the cerebellum and basal ganglia-while no motor improvement was observed when these cell-based therapeutic approaches were applied in the spinal cord. However, the effects observed were mild and transient, suggesting that continuous or repeated administration would be needed, which should be further tested.

9.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445620

RESUMO

The clinical success of cisplatin, carboplatin, and oxaliplatin has sparked the interest of medicinal inorganic chemistry to synthesize and study compounds with non-platinum metal centers. Despite Ru(II)-polypyridyl complexes being widely studied and well established for their antitumor properties, there are not enough in vivo studies to establish the potentiality of this type of compound. Therefore, we report to the best of our knowledge the first in vivo study of Ru(II)-polypyridyl complexes against breast cancer with promising results. In order to conduct our study, we used MCF7 zebrafish xenografts and ruthenium complexes [Ru(bipy)2(C12H8N6-N,N)][CF3SO3]2Ru1 and [{Ru(bipy)2}2(µ-C12H8N6-N,N)][CF3SO3]4Ru2, which were recently developed by our group. Ru1 and Ru2 reduced the tumor size by an average of 30% without causing significant signs of lethality when administered at low doses of 1.25 mg·L-1. Moreover, the in vitro selectivity results were confirmed in vivo against MCF7 breast cancer cells. Surprisingly, this work suggests that both the mono- and the dinuclear Ru(II)-polypyridyl compounds have in vivo potential against breast cancer, since there were no significant differences between both treatments, highlighting Ru1 and Ru2 as promising chemotherapy agents in breast cancer therapy.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Compostos de Rutênio/química , Compostos de Rutênio/farmacologia , Animais , Apoptose , Neoplasias da Mama/patologia , Proliferação de Células , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Técnicas In Vitro , Estrutura Molecular , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
10.
Neurol Sci ; 42(7): 2955-2959, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33517539

RESUMO

INTRODUCTION: Adult polyglucosan body disease (APBD) is an autosomal recessive leukodystrophy characterized by neurogenic bladder starting after 40 years old, spastic paraparesis and peripheral neuropathy. It is mainly resultant from the GBE1 homozygous p.Tyr329Ser (c.986A>C) mutation, especially in Ashkenazi-Jewish patients, although some cases of compound heterozygous have been reported. A genotype-phenotype correlation is not established, but atypical phenotypes have been described mainly in non-p.Tyr329Ser pathogenic variants. CASE REPORT: We describe an atypical case in a 62-year-old Portuguese woman, presenting the typical clinical triad of APBD plus prominent autonomic dysfunction, suggested by orthostatic hypotension and thermoregulatory dysfunction; she has compound heterozygous GBE1 mutations, namely, p.Asn541Asp (c.1621A>G) and p.Arg515Gly (c.1543C>G), the last one not yet reported in literature and whose pathogenicity was suggested by bioinformatics analysis and confirmed by sural nerve biopsy that showed intra-axonal polyglucosan bodies. DISCUSSION: Besides the report of a novel GBE1 mutation, this case also expands the phenotypic spectrum of this disorder, reinforcing autonomic dysfunction as a possible and prominent manifestation of APBD, mimicking autosomal dominant leukodystrophy with autonomic disease in some way. Therefore, we questioned a possible relationship between this genotype and the phenotype marked by dysautonomia. Additionally, we review previously reported cases of APBD in non-homozygous p.Tyr329Ser patients with atypical phenotypes.


Assuntos
Sistema da Enzima Desramificadora do Glicogênio , Doença de Depósito de Glicogênio , Doenças do Sistema Nervoso , Adulto , Feminino , Sistema da Enzima Desramificadora do Glicogênio/genética , Homozigoto , Humanos , Pessoa de Meia-Idade , Mutação
11.
Expert Opin Ther Targets ; 24(11): 1099-1119, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32962458

RESUMO

INTRODUCTION: Six of the most frequent dominantly inherited spinocerebellar ataxias (SCAs) worldwide - SCA1, SCA2, SCA3, SCA6, SCA7, and SCA17 - are caused by an expansion of a polyglutamine (polyQ) tract in the corresponding proteins. While the identification of the causative mutation has advanced knowledge on the pathogenesis of polyQ SCAs, effective therapeutics able to mitigate the severe clinical manifestation of these highly incapacitating disorders are not yet available. AREAS COVERED: This review provides a comprehensive and critical perspective on well-established and emerging therapeutic targets for polyQ SCAs; it aims to inspire prospective drug discovery efforts. EXPERT OPINION: The landscape of polyQ SCAs therapeutic targets and strategies includes (1) the mutant genes and proteins themselves, (2) enhancement of endogenous protein quality control responses, (3) abnormal protein-protein interactions of the mutant proteins, (4) disturbed neuronal function, (5) mitochondrial function, energy availability and oxidative stress, and (6) glial dysfunction, growth factor or hormone imbalances. Challenges include gaining a clearer definition of therapeutic targets for the drugs in clinical development, the discovery of novel drug-like molecules for challenging key targets, and the attainment of a stronger translation of preclinical findings to the clinic.


Assuntos
Terapia de Alvo Molecular , Peptídeos/metabolismo , Ataxias Espinocerebelares/tratamento farmacológico , Animais , Desenvolvimento de Medicamentos , Descoberta de Drogas , Humanos , Estresse Oxidativo , Ataxias Espinocerebelares/fisiopatologia
12.
Mol Cell Neurosci ; 96: 1-9, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30771505

RESUMO

Parkinson's disease (PD) is a progressive neurological disorder, mainly characterized by the progressive loss of dopaminergic neurons in the Substantia nigra pars compacta (SNpc) and by the presence of intracellular inclusions, known as Lewy bodies. Despite SNpc being considered the primary affected region in PD, the neuropathological features are confined solely to the nigro-striatal axis. With disease progression other brain regions are also affected, namely the cerebral cortex, although the spreading of the neurologic damage to this region is still not completely unraveled. Tauroursodeoxycholic acid (TUDCA) is an endogenous bile acid that has been shown to have antioxidant properties and to exhibit a neuroprotective effect in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mice model of PD. Moreover, TUDCA anti-inflammatory properties have been reported in glial cells, making it a prominent therapeutic agent in PD. Here, we used C57BL/6 mice injected with MPTP in a sub-acute paradigm aiming to investigate if the neurotoxic effects of MPTP could be extended to the cerebral cortex. In parallel, we evaluated the anti-oxidant, neuroprotective and anti-inflammatory effects of TUDCA. The anti-inflammatory mechanisms elicited by TUDCA were further dissected in microglia cells. Our results show that MPTP leads to a decrease of ATP and activated AMP-activated protein kinase levels in mice cortex, and to a transient increase in the expression of antioxidant downstream targets of nuclear factor erythroid 2 related factor 2 (Nrf-2), and parkin. Notably, MPTP increases pro-inflammatory markers, while down-regulating the expression of the anti-inflammatory protein Annexin-A1 (ANXA1). Importantly, we show that TUDCA treatment prevents the deleterious effects of MPTP, sustains increased levels of antioxidant enzymes and parkin, and most of all negatively modulates neuroinflammation and up-regulates ANXA1 expression. Additionally, results from cellular models using microglia corroborate TUDCA modulation of ANXA1 synthesis, linking inhibition of neuroinflammation and neuroprotection by TUDCA.


Assuntos
Anti-Inflamatórios/farmacologia , Córtex Cerebral/efeitos dos fármacos , Intoxicação por MPTP/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Ácido Tauroquenodesoxicólico/farmacologia , Quinases Proteína-Quinases Ativadas por AMP , Trifosfato de Adenosina/metabolismo , Animais , Anexina A1/genética , Anexina A1/metabolismo , Anti-Inflamatórios/uso terapêutico , Linhagem Celular , Córtex Cerebral/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Proteínas Quinases/metabolismo , Ácido Tauroquenodesoxicólico/uso terapêutico , Ubiquitina-Proteína Ligases/metabolismo
13.
J Neurointerv Surg ; 11(2): 200-203, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30097484

RESUMO

INTRODUCTION: Recently, the benefit of selecting patients for endovascular treatment (EVT) beyond the 6-hour time window using a tissue-based approach was demonstrated in two randomized trials. The optimal imaging protocol for selecting patients is under debate, and it is still unknown if a simpler and faster protocol may adequately select patients with wake-up stroke (WUS) and late-presenting stroke (LPS) for EVT. OBJECTIVE: To compare outcomes of patients submitted to EVT presenting within 6 hours of symptom onset or 6-24 hours after last seen well, selected using non-contrast computed tomography (NCCT) and CT angiography (CTA). METHODS: An observational study was performed, which included consecutive patients with anterior circulation ischemic stroke with large vessel occlusion treated with EVT. Patients presenting within 6 hours were treated if their NIH Stroke Scale (NIHSS) score was ≥6 and Alberta Stroke Program Early CT score (ASPECTS) was ≥6, while patients presenting with WUS or 6-24 hours after last seen well (WUS/LPS) were treated if their NIHSSscore was ≥12 and ASPECTS was ≥7. RESULTS: 249 patients were included, 63 of whom were in the WUS/LPS group. Baseline characteristics were similar between groups, except for longer symptom-recanalization time, lower admission NIHSS (16 vs 17, P=0.038), more frequent tandem occlusions (25.4% vs 11.8%, P=0.010), and large artery atherosclerosis etiology (22.2% vs 11.8%, P=0.043) in the WUS/LPS group. No differences in symptomatic intracranial hemorrhage, peri-procedural complications or mortality were found between groups. Three-month functional independence was similar in both groups (65.1% in WUS/LPS vs 57.0% in ≤6 hours, P=0.259) and no differences were found after adjustment for confounders. CONCLUSIONS: This real-world observational study suggests that EVT may be safe and effective in patients with WUS and LPS selected using clinical-core mismatch (high NIHSS/high ASPECTS in NCCT).


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Procedimentos Endovasculares/métodos , Seleção de Pacientes , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Acidente Vascular Cerebral/terapia , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
14.
Inorg Chem ; 57(21): 13150-13166, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30339386

RESUMO

Ruthenium(II) complexes are currently considered a viable alternative to the widely used platinum complexes as efficient anticancer agents. We herein present the synthesis and characterization of half-sandwich ruthenium compounds with the general formula [Ru( p-cymene)(L-N,N)Cl][CF3SO3] (L = 3,6-di-2-pyridyl-1,2,4,5-tetrazine (1) 6,7-dimethyl-2,3-bis(pyridin-2-yl)quinoxaline (2)), which have been synthesized by substitution reactions from the precursor dimer [Ru( p-cymene)(Cl)(µ-Cl)]2 and were characterized by elemental analysis, mass spectrometry, 1H NMR, UV-vis, and IR spectroscopy, conductivity measurements, and cyclic voltammetry. The molecular structure for complex 2 was determined by single-crystal X-ray diffraction. The cytotoxic activity of these compounds was evaluated against human tumor cells, namely ovarian carcinoma A2780 and breast MCF7 and MDAMB231 adenocarcinoma cells, and against normal primary fibroblasts. Whereas the cytotoxic activity of 1 is moderate, IC50 values found for 2 are among the lowest previously reported for Ru( p-cymene) complexes. Both compounds present no cytotoxic effect in normal human primary fibroblasts when they are used at the IC50 concentration in A2780 and MCF7 cancer cells. Their antiproliferative capacity is associated with a combined mechanism of apoptosis and autophagy. A strong interaction with DNA was observed for both with a binding constant value of the same magnitude as that of the classical intercalator [Ru(phen)2(dppz)]2+. Both complexes bind to human serum albumin with moderate to strong affinity, with conditional binding constants (log Kb) of 4.88 for complex 2 and 5.18 for complex 1 in 2% DMSO/10 mM Hepes pH7.0 medium. The acute toxicity was evaluated in zebrafish embryo model using the fish embryo acute toxicity test (FET). Remarkably, our results show that compounds 1 and 2 are not toxic/lethal even at extremely high concentrations. The novel compounds reported herein are highly relevant antitumor metallodrug candidates, given their in vitro cytotoxicity toward cancer cells and the lack of in vivo toxicity.


Assuntos
Antineoplásicos/farmacologia , Complexos de Coordenação/farmacologia , Monoterpenos/farmacologia , Rutênio/farmacologia , Animais , Antineoplásicos/efeitos adversos , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/efeitos adversos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cimenos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Monoterpenos/efeitos adversos , Monoterpenos/química , Rutênio/efeitos adversos , Rutênio/química , Relação Estrutura-Atividade , Peixe-Zebra
15.
Braz. j. oral sci ; 15(4): 258-263, Oct.-Dec. 2016. ilus
Artigo em Inglês | LILACS, BBO | ID: biblio-875690

RESUMO

Self-adhesive, dual-polymerizing resin cements require no treatment to the prepared tooth surfaces before cementation. Aim: The aim of this study was to evaluate the influence of curing mode on bond strength (BS) of three cementing systems to bovine dentin. Methods: The buccal enamel surfaces of 50 bovine incisors were removed to expose dentin and to flat the surface. The teeth were divided into five groups (n=10), which consisted of two resin cements (Multilink and Clearfil SA Cement) that were tested in dual- (halogen light for 40 s) and self-cured modes, and a control (RelyX ARC). Two cylinders of resin cements (1.0 mm X 0.75 mm) were prepared on each bonded dentin surface. After 24h at 37oC, resin cylinders were subjected to micro-shear testing in a universal testing machine (4411/Instron - 0.5 mm/min). Data were statistically analyzed by two-way ANOVA, Tukey and Dunnett`s test (5%). Results: Multilink showed higher BS than those observed on Clearfil SA. Light-curing resulted in higher BS for both Multilink and Clearfil SA. When Multilink was light-cured, no significant difference on BS was demonstrated between it and RelyX ARC. Conclusions: The highest BS values were obtained in control group and light-cured Multilink resin cement (AU)


Assuntos
Animais , Bovinos , Adesivos , Dentina , Cimentos de Resina , Resistência à Tração
16.
FEBS Lett ; 590(10): 1455-66, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27086966

RESUMO

Oxidative stress is a key pathological feature of Parkinson's disease (PD). Glutathione S-transferase pi (GSTP) is a neuroprotective antioxidant enzyme regulated at the transcriptional level by the antioxidant master regulator nuclear factor-erythroid 2-related factor 2 (Nrf2). Here, we show for the first time that upon MPTP-induced oxidative stress, GSTP potentiates S-glutathionylation of Kelch-like ECH-associated protein 1 (Keap1), an endogenous repressor of Nrf2, in vivo. S-glutathionylation of Keap1 leads to Nrf2 activation and subsequently increases expression of GSTP. This positive feedback regulatory loop represents a novel mechanism by which GSTP elicits antioxidant protection in the brain.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/efeitos adversos , Encéfalo/metabolismo , Glutationa S-Transferase pi/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Retroalimentação Fisiológica , Regulação da Expressão Gênica , Glutationa/metabolismo , Glutationa S-Transferase pi/genética , Proteína 1 Associada a ECH Semelhante a Kelch/química , Camundongos , Modelos Moleculares , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/química , Estresse Oxidativo , Ligação Proteica
17.
Rev. APS ; 18(1)jan. 2015.
Artigo em Português | LILACS | ID: lil-771363

RESUMO

A cárie dental é uma patologia multifatorial, transmissível,que possui como característica etiológica a interação defatores biológicos e sociais. Apresenta-se como a doen-ça crônica mais comum na infância, sendo, portanto, umgrande desafio para a saúde pública em nível mundial. Oobjetivo do presente estudo foi, através de uma abordagemquantitativa e qualitativa, avaliar os determinantes sociais ebiológicos da cárie dental em crianças de 0 a 2 anos de idade,assim como promover ações que venham proporcionaruma maior integração interdisciplinar na assistência àsaúde bucal. Os resultados obtidos demonstram a falta deconhecimento dos responsáveis quanto aos principais fatoresde risco para a cárie dentária, na faixa etária pesquisada,assim como evidencia o quanto os mesmos subestimama importância da assistência à saúde bucal dessascrianças. Diante disso, fica evidente a necessidade de esforçosinterdisciplinares constantes para o enfrentamentodo problema, com a participação ativa de todos os profissionaisde saúde envolvidos na atenção primária à saúde.


The dental caries condition is a multifactorial disease,transmissible, whose etiology is characterized by theinteraction of biological and social factors. It is the mostcommon chronic childhood disease and is thereforea major challenge to public health worldwide. Theobjective of this study was, through a quantitative andqualitative approach, to evaluate the social and biologicaldeterminants of dental caries in children from 0 to 2 yearsof age, and to promote actions that would provide greaterinterdisciplinary integration in oral health care. The resultsfound demonstrate the lack of knowledge of the adultsresponsible, regarding the main risk factors for dentalcaries in the age group studied, as well as highlight howthose adults underestimate the importance of oral healthcare for these children. Thus there is an obvious need forongoing interdisciplinary efforts to address the problem,with the active participation of all health professionalsinvolved in primary health care.


Assuntos
Higiene Bucal , Assistência Odontológica para Crianças , Cárie Dentária , Serviços de Saúde Bucal , Profilaxia Dentária
18.
Hum Mol Genet ; 24(1): 100-17, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25143392

RESUMO

The physiological function of Ataxin-3 (ATXN3), a deubiquitylase (DUB) involved in Machado-Joseph Disease (MJD), remains elusive. In this study, we demonstrate that ATXN3 is required for neuronal differentiation and for normal cell morphology, cytoskeletal organization, proliferation and survival of SH-SY5Y and PC12 cells. This cellular phenotype is associated with increased proteasomal degradation of α5 integrin subunit (ITGA5) and reduced activation of integrin signalling and is rescued by ITGA5 overexpression. Interestingly, silencing of ATXN3, overexpression of mutant versions of ATXN3 lacking catalytic activity or bearing an expanded polyglutamine (polyQ) tract led to partially overlapping phenotypes. In vivo analysis showed that both Atxn3 knockout and MJD transgenic mice had decreased levels of ITGA5 in the brain. Furthermore, abnormal morphology and reduced branching were observed both in cultured neurons expressing shRNA for ATXN3 and in those obtained from MJD mice. Our results show that ATXN3 rescues ITGA5 from proteasomal degradation in neurons and that polyQ expansion causes a partial loss of this cellular function, resulting in reduced integrin signalling and neuronal cytoskeleton modifications, which may be contributing to neurodegeneration.


Assuntos
Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Proteínas Nucleares/metabolismo , Peptídeos/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Animais , Ataxina-3 , Diferenciação Celular , Células Cultivadas , Gânglios Espinais/citologia , Gânglios Espinais/metabolismo , Células HEK293 , Hipocampo/citologia , Hipocampo/metabolismo , Humanos , Integrina alfa5/metabolismo , Camundongos , Células PC12 , Complexo de Endopeptidases do Proteassoma/metabolismo , Ratos , Ratos Wistar
19.
Stem Cell Rev Rep ; 11(2): 288-97, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25420577

RESUMO

It was recently shown that the conditioned media (CM) of Human Umbilical Cord Perivascular Cells (HUCPVCs), a mesenchymal progenitor population residing within the Wharton Jelly of the umbilical cord, was able to modulate in vitro the survival and viability of different neuronal and glial cells populations. In the present work, we aimed to assess if the secretome of HUCPVCs is able to 1) induce the differentiation of human telencephalon neural precursor cells (htNPCs) in vitro, and 2) modulate neural/glial proliferation, differentiation and survival in the dentate gyrus (DG) of adult rat hippocampus. For this purpose, two separate experimental setups were performed: 1) htNPCs were incubated with HUCPVCs-CM for 5 days after which neuronal differentiation was assessed and, 2) HUCPVCs, or their respective CM, were injected into the DG of young adult rats and their effects assessed 7 days later. Results revealed that the secretome of HUCPVCs was able to increase neuronal cell differentiation in vitro; indeed, higher densities of immature (DCX(+) cells) and mature neurons (MAP-2(+) cells) were observed when htNPCs were incubated with the HUCPVCs-CM. Additionally, when HUCPVCs and their CM were injected in the DG, results revealed that both cells or CM were able to increase the endogenous proliferation (BrdU(+) cells) 7 days after injection. It was also possible to observe an increased number of newborn neurons (DCX(+) cells), upon injection of HUCPVCs or their respective CM. Finally western blot analysis revealed that after CM or HUCPVCs transplantation, there was an increase of fibroblast growth factor-2 (FGF-2) and, to a lesser extent, of nerve growth factor (NGF) in the DG tissue. Concluding, our results have shown that the transplantation of HUCPVCs or the administration of their secretome were able to potentiate neuronal survival and differentiation in vitro and in vivo.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Células-Tronco Neurais/transplante , Neurogênese/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Giro Denteado/citologia , Giro Denteado/efeitos dos fármacos , Giro Denteado/crescimento & desenvolvimento , Proteína Duplacortina , Humanos , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Neurais/metabolismo , Neuroglia/citologia , Neuroglia/efeitos dos fármacos , Neurônios/citologia , Ratos , Telencéfalo/citologia , Telencéfalo/crescimento & desenvolvimento , Cordão Umbilical/citologia , Cordão Umbilical/crescimento & desenvolvimento , Cordão Umbilical/metabolismo
20.
Liver Transpl ; 21(3): 282-92, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25482846

RESUMO

Hereditary transthyretin amyloidosis (ATTR) is a rare worldwide autosomal dominant disease caused by the systemic deposition of an amyloidogenic variant of transthyretin (TTR), which is usually derived from a single amino acid substitution in the TTR gene. More than 100 mutations have been described, with V30M being the most prevalent. Each variant has a different involvement, although peripheral neuropathy and cardiomyopathy are the most common. Orthotopic liver transplantation (OLT) was implemented as the inaugural disease-modifying therapy because the liver produces the circulating unstable TTR. In this review, we focus on the results and long-term outcomes of OLT for ATTR after more than 2063 procedures and 23 years of experience. After successful OLT, neuropathy and organ impairment are not usually reversed, and in some cases, the disease progresses. The overall 5-year survival rate is approximately 100% for V30M patients and 59% for non-ATTR V30M patients. Cardiac-related death and septicemia are the main causes of mortality. Lower survival is related to malnutrition, a longer duration of disease, cardiomyopathy, and a later onset (particularly for males). Deposits, which are composed of a mixture of truncated and full-length TTR (type A) fibrils, have been associated with posttransplant myocardial dysfunction. A higher incidence of early hepatic artery thrombosis of the graft has also been documented for these patients. Liver-kidney/heart transplantation is an alternative for patients with advanced renal disease or heart failure. The sequential procedure, in which ATTR livers are reused in patients with liver disease, reveals that neuropathy in the recipient may appear as soon as 6 years after OLT, and ATTR deposits may appear even earlier. Long-term results of trials with amyloid protein stabilizers or disrupters, silencing RNA, and antisense oligonucleotides will highlight the value and limitations of liver transplantation.


Assuntos
Neuropatias Amiloides Familiares/cirurgia , Transplante de Fígado , Fígado/metabolismo , Pré-Albumina/metabolismo , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/metabolismo , Neuropatias Amiloides Familiares/mortalidade , Progressão da Doença , Predisposição Genética para Doença , Humanos , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Transplante de Fígado/mortalidade , Mutação , Seleção de Pacientes , Pré-Albumina/genética , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
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