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1.
Nature ; 623(7985): 157-166, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37853118

RESUMO

Immunotherapy failures can result from the highly suppressive tumour microenvironment that characterizes aggressive forms of cancer such as recurrent glioblastoma (rGBM)1,2. Here we report the results of a first-in-human phase I trial in 41 patients with rGBM who were injected with CAN-3110-an oncolytic herpes virus (oHSV)3. In contrast to other clinical oHSVs, CAN-3110 retains the viral neurovirulence ICP34.5 gene transcribed by a nestin promoter; nestin is overexpressed in GBM and other invasive tumours, but not in the adult brain or healthy differentiated tissue4. These modifications confer CAN-3110 with preferential tumour replication. No dose-limiting toxicities were encountered. Positive HSV1 serology was significantly associated with both improved survival and clearance of CAN-3110 from injected tumours. Survival after treatment, particularly in individuals seropositive for HSV1, was significantly associated with (1) changes in tumour/PBMC T cell counts and clonal diversity, (2) peripheral expansion/contraction of specific T cell clonotypes; and (3) tumour transcriptomic signatures of immune activation. These results provide human validation that intralesional oHSV treatment enhances anticancer immune responses even in immunosuppressive tumour microenvironments, particularly in individuals with cognate serology to the injected virus. This provides a biological rationale for use of this oncolytic modality in cancers that are otherwise unresponsive to immunotherapy (ClinicalTrials.gov: NCT03152318 ).


Assuntos
Neoplasias Encefálicas , Glioblastoma , Herpesvirus Humano 1 , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Glioblastoma/imunologia , Glioblastoma/patologia , Nestina/genética , Terapia Viral Oncolítica/efeitos adversos , Vírus Oncolíticos/genética , Vírus Oncolíticos/imunologia , Vírus Oncolíticos/fisiologia , Reprodutibilidade dos Testes , Análise de Sobrevida , Linfócitos T/citologia , Linfócitos T/imunologia , Resultado do Tratamento , Microambiente Tumoral/imunologia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 1/fisiologia
2.
PLoS Genet ; 19(2): e1010666, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36809245

RESUMO

Chromosome movements and licensing of synapsis must be tightly regulated during early meiosis to ensure accurate chromosome segregation and avoid aneuploidy, although how these steps are coordinated is not fully understood. Here we show that GRAS-1, the worm homolog of mammalian GRASP/Tamalin and CYTIP, coordinates early meiotic events with cytoskeletal forces outside the nucleus. GRAS-1 localizes close to the nuclear envelope (NE) in early prophase I and interacts with NE and cytoskeleton proteins. Delayed homologous chromosome pairing, synaptonemal complex (SC) assembly, and DNA double-strand break repair progression are partially rescued by the expression of human CYTIP in gras-1 mutants, supporting functional conservation. However, Tamalin, Cytip double knockout mice do not exhibit obvious fertility or meiotic defects, suggesting evolutionary differences between mammals. gras-1 mutants show accelerated chromosome movement during early prophase I, implicating GRAS-1 in regulating chromosome dynamics. GRAS-1-mediated regulation of chromosome movement is DHC-1-dependent, placing it acting within the LINC-controlled pathway, and depends on GRAS-1 phosphorylation at a C-terminal S/T cluster. We propose that GRAS-1 coordinates the early steps of homology search and licensing of SC assembly by regulating the pace of chromosome movement in early prophase I.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Humanos , Camundongos , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Pareamento Cromossômico , Segregação de Cromossomos , Mamíferos/genética , Meiose , Prófase Meiótica I , Complexo Sinaptonêmico/metabolismo
3.
Gastroenterology ; 166(5): 859-871.e3, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38280684

RESUMO

BACKGROUND & AIMS: The complex tumor microenvironment (TME) of pancreatic ductal adenocarcinoma (PDAC) has hindered the development of reliable predictive biomarkers for targeted therapy and immunomodulatory strategies. A comprehensive characterization of the TME is necessary to advance precision therapeutics in PDAC. METHODS: A transcriptomic profiling platform for TME classification based on functional gene signatures was applied to 14 publicly available PDAC datasets (n = 1657) and validated in a clinically annotated independent cohort of patients with PDAC (n = 79). Four distinct subtypes were identified using unsupervised clustering and assessed to evaluate predictive and prognostic utility. RESULTS: TME classification using transcriptomic profiling identified 4 biologically distinct subtypes based on their TME immune composition: immune enriched (IE); immune enriched, fibrotic (IE/F); fibrotic (F); and immune depleted (D). The IE and IE/F subtypes demonstrated a more favorable prognosis and potential for response to immunotherapy compared with the F and D subtypes. Most lung metastases and liver metastases were subtypes IE and D, respectively, indicating the role of clonal phenotype and immune milieu in developing personalized therapeutic strategies. In addition, distinct TMEs with potential therapeutic implications were identified in treatment-naive primary tumors compared with tumors that underwent neoadjuvant therapy. CONCLUSIONS: This novel approach defines a distinct subgroup of PADC patients that may benefit from immunotherapeutic strategies based on their TME subtype and provides a framework to select patients for prospective clinical trials investigating precision immunotherapy in PDAC. Further, the predictive utility and real-world clinical applicability espoused by this transcriptomic-based TME classification approach will accelerate the advancement of precision medicine in PDAC.


Assuntos
Biomarcadores Tumorais , Carcinoma Ductal Pancreático , Perfilação da Expressão Gênica , Neoplasias Pancreáticas , Medicina de Precisão , Transcriptoma , Microambiente Tumoral , Humanos , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/terapia , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Biomarcadores Tumorais/genética , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Regulação Neoplásica da Expressão Gênica , Imunoterapia/métodos , Prognóstico , Terapia Neoadjuvante , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Valor Preditivo dos Testes , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Bases de Dados Genéticas
4.
Blood ; 142(26): 2282-2295, 2023 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-37774374

RESUMO

ABSTRACT: The spatial anatomy of hematopoiesis in the bone marrow (BM) has been extensively studied in mice and other preclinical models, but technical challenges have precluded a commensurate exploration in humans. Institutional pathology archives contain thousands of paraffinized BM core biopsy tissue specimens, providing a rich resource for studying the intact human BM topography in a variety of physiologic states. Thus, we developed an end-to-end pipeline involving multiparameter whole tissue staining, in situ imaging at single-cell resolution, and artificial intelligence-based digital whole slide image analysis and then applied it to a cohort of disease-free samples to survey alterations in the hematopoietic topography associated with aging. Our data indicate heterogeneity in marrow adipose tissue (MAT) content within each age group and an inverse correlation between MAT content and proportions of early myeloid and erythroid precursors, irrespective of age. We identify consistent endosteal and perivascular positioning of hematopoietic stem and progenitor cells (HSPCs) with medullary localization of more differentiated elements and, importantly, uncover new evidence of aging-associated changes in cellular and vascular morphologies, microarchitectural alterations suggestive of foci with increased lymphocytes, and diminution of a potentially active megakaryocytic niche. Overall, our findings suggest that there is topographic remodeling of human hematopoiesis associated with aging. More generally, we demonstrate the potential to deeply unravel the spatial biology of normal and pathologic human BM states using intact archival tissue specimens.


Assuntos
Inteligência Artificial , Células-Tronco Hematopoéticas , Humanos , Camundongos , Animais , Células-Tronco Hematopoéticas/patologia , Medula Óssea/patologia , Hematopoese/fisiologia , Envelhecimento
5.
Anal Biochem ; 685: 115390, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37951454

RESUMO

To alleviate environmental problems caused by using conventional plastics, bioplastics have garnered significant interest as alternatives to petroleum-based plastics. Despite possessing better degradability traits compared to traditional plastics, the degradation of bioplastics still demands a longer duration than initially anticipated. This necessitates the utilization of degradation strains or enzymes to enhance degradation efficiency, ensuring timely degradation. In this study, a novel screening method to identify bioplastic degraders faster was suggested to circumvent the time-consuming and laborious characteristics of solid-based plate assays. This liquid-based colorimetric method confirmed the extracellular esterase activity with p-nitrophenyl esters. It eliminated the needs to prepare plastic emulsion plates at the initial screening system, shortening the time for the overall screening process and providing more quantitative data. p-nitrophenyl hexanoate (C6) was considered the best substrate among the various p-nitrophenyl esters as substrates. The screening was performed in liquid-based 96-well plates, resulting in the discovery of a novel strain, Bacillus sp. SH09, with a similarity of 97.4% with Bacillus licheniformis. Furthermore, clear zone assays, degradation investigations, scanning electron microscopy, and gel permeation chromatography were conducted to characterize the biodegradation capabilities of the new strain, the liquid-based approach offered a swift and less labor-intensive option during the initial stages.


Assuntos
Esterases , Plásticos , Plásticos/química , Esterases/química , Ensaios de Triagem em Larga Escala , Colorimetria , Biopolímeros
6.
J Org Chem ; 89(9): 6230-6237, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38629386

RESUMO

A concise synthesis of pareitropone by oxidative cyclization of a phenolic nitronate is delineated. The use of TMSOTf as an additive to promote the facile formation of a strained norcaradiene intermediate provides convenient access to highly condensed multicyclic tropones in high yields. This synthesis is modular, efficient, and scalable, highlighting the synthetic utility of radical anion coupling reactions in annulation reactions. This work is discussed in the context of total syntheses of the tropoloisoquinoline alkaloids. Also included are the preparation of several congeners and a brief description of their biological activities.


Assuntos
Antineoplásicos , Humanos , Estrutura Molecular , Ciclização , Linhagem Celular Tumoral , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Oxirredução
7.
PLoS Genet ; 17(7): e1009715, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34329293

RESUMO

Histone methylation is dynamically regulated to shape the epigenome and adjust central nuclear processes including transcription, cell cycle control and DNA repair. Lysine-specific histone demethylase 2 (LSD2) has been implicated in multiple types of human cancers. However, its functions remain poorly understood. This study investigated the histone demethylase LSD2 homolog AMX-1 in C. elegans and uncovered a potential link between H3K4me2 modulation and DNA interstrand crosslink (ICL) repair. AMX-1 is a histone demethylase and mainly localizes to embryonic cells, the mitotic gut and sheath cells. Lack of AMX-1 expression resulted in embryonic lethality, a decreased brood size and disorganized premeiotic tip germline nuclei. Expression of AMX-1 and of the histone H3K4 demethylase SPR-5 is reciprocally up-regulated upon lack of each other and the mutants show increased H3K4me2 levels in the germline, indicating that AMX-1 and SPR-5 regulate H3K4me2 demethylation. Loss of AMX-1 function activates the CHK-1 kinase acting downstream of ATR and leads to the accumulation of RAD-51 foci and increased DNA damage-dependent apoptosis in the germline. AMX-1 is required for the proper expression of mismatch repair component MutL/MLH-1 and sensitivity against ICLs. Interestingly, formation of ICLs lead to ubiquitination-dependent subcellular relocalization of AMX-1. Taken together, our data suggest that AMX-1 functions in ICL repair in the germline.


Assuntos
Reparo do DNA/genética , Histona Desmetilases/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans , Núcleo Celular/metabolismo , Dano ao DNA/genética , Reparo do DNA/fisiologia , Células Germinativas/metabolismo , Histona Desmetilases/fisiologia , Histonas/genética , Metilação , Processamento de Proteína Pós-Traducional/genética , Ubiquitinação
8.
Microb Cell Fact ; 22(1): 184, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715205

RESUMO

BACKGROUND: Bioplastics are attracting considerable attention, owing to the increase in non-degradable waste. Using microorganisms to degrade bioplastics is a promising strategy for reducing non-degradable plastic waste. However, maintaining bacterial viability and activity during culture and storage remains challenging. With the use of conventional methods, cell viability and activity was lost; therefore, these conditions need to be optimized for the practical application of microorganisms in bioplastic degradation. Therefore, we aimed to optimize the feasibility of the lyophilization method for convenient storage and direct use. In addition, we incoporated protective reagents to increase the viability and activity of lyophilized microorganisms. By selecting and applying the best protective reagents for the lyophilization process and the effects of additives on the growth and PHB-degrading activity of strains were analyzed after lyophilization. For developing the lyophilization method for protecting degradation activity, it may promote practical applications of bioplastic-degrading bacteria. RESULTS: In this study, the polyhydroxybutyrate (PHB)-degrading strain, Bacillus sp. JY14 was lyophilized with the use of various sugars as protective reagents. Among the carbon sources tested, raffinose was associated with the highest cell survival rate (12.1%). Moreover, 7% of raffionose showed the highest PHB degradation yield (92.1%). Therefore, raffinose was selected as the most effective protective reagent. Also, bacterial activity was successfully maintained, with raffinose, under different storage temperatures and period. CONCLUSIONS: This study highlights lyophilization as an efficient microorganism storage method to enhance the applicability of bioplastic-degrading bacterial strains. The approach developed herein can be further studied and used to promote the application of microorganisms in bioplastic degradation.


Assuntos
Bacillus , Rafinose , Carbono , Liofilização
9.
PLoS Genet ; 16(1): e1008529, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31917788

RESUMO

Exposure to diethylhexyl phthalate (DEHP), the most abundant plasticizer used in the production of polyvinyl-containing plastics, has been associated to adverse reproductive health outcomes in both males and females. While the effects of DEHP on reproductive health have been widely investigated, the molecular mechanisms by which exposure to environmentally-relevant levels of DEHP and its metabolites impact the female germline in the context of a multicellular organism have remained elusive. Using the Caenorhabditis elegans germline as a model for studying reprotoxicity, we show that exposure to environmentally-relevant levels of DEHP and its metabolites results in increased meiotic double-strand breaks (DSBs), altered DSB repair progression, activation of p53/CEP-1-dependent germ cell apoptosis, defects in chromosome remodeling at late prophase I, aberrant chromosome morphology in diakinesis oocytes, increased chromosome non-disjunction and defects during early embryogenesis. Exposure to DEHP results in a subset of nuclei held in a DSB permissive state in mid to late pachytene that exhibit defects in crossover (CO) designation/formation. In addition, these nuclei show reduced Polo-like kinase-1/2 (PLK-1/2)-dependent phosphorylation of SYP-4, a synaptonemal complex (SC) protein. Moreover, DEHP exposure leads to germline-specific change in the expression of prmt-5, which encodes for an arginine methyltransferase, and both increased SC length and altered CO designation levels on the X chromosome. Taken together, our data suggest a model by which impairment of a PLK-1/2-dependent negative feedback loop set in place to shut down meiotic DSBs, together with alterations in chromosome structure, contribute to the formation of an excess number of DSBs and altered CO designation levels, leading to genomic instability.


Assuntos
Troca Genética , Quebras de DNA de Cadeia Dupla , Dietilexilftalato/toxicidade , Oogênese , Oogônios/efeitos dos fármacos , Plastificantes/toxicidade , Animais , Apoptose , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Instabilidade Genômica , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Oogônios/citologia , Oogônios/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
10.
Br J Nutr ; 128(3): 542-548, 2022 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-34503592

RESUMO

This study investigated the association between the different types of plant-based diets and dyslipidaemia in Korean adults using data from the nationally representative sample. Using the 2012­2016 Korea National Health and Nutrition Survey data, a total of 14 167 adults (≥19 years old) participated in this study. Dietary intake was assessed by a semi-quantitative FFQ. Three different plant-based diet indices (overall plant-based diet index (PDI), healthful plant-based diet index (hPDI), unhealthful plant-based diet index (uPDI)), were calculated. Dyslipidaemia and its components (hypertriacylglycerolaemia, hypercholesterolaemia, low HDL-cholesterol, high LDL-cholesterol, use of anti-hyperlipidaemia agent) were measured. Multivariable logistic regression analysis was used to examine the associations between plant-based diet and dyslipidaemia and individual lipid disorders. Totally, 47% of overall population had dyslipidaemia. Individual in the highest quintile of uPDI had 22% greater odds of dyslipidaemia (95 % CI 1·05, 1·41) and 48 % higher odds of hypertriacylglycerolaemia (95 % CI 1·21, 1·81) and 16% higher odds of low HDL-cholesterol (OR: 1·16, 95 % CI 1·00, 1·35) than those in the lowest quintile of uPDI. PDI was associated with 16 % higher odds of low HDL-cholesterol, and hPDI was associated with 25% lower odds of high LDL-cholesterol. However, neither PDI nor hPDI was significantly associated with the prevalence of dyslipidaemia. Greater adherence to unhealthful plant-based diets was associated with greater odds of the dyslipidaemia and its components suggesting the importance of the quality of plant-based diet in South Korean adults for dyslipidaemia prevention.


Assuntos
Dieta Vegetariana , Dislipidemias , Adulto , Humanos , Adulto Jovem , Dieta , República da Coreia , Colesterol
11.
Nanomedicine ; 44: 102576, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35714922

RESUMO

Targeting microglial activation is emerging as a clinically promising drug target for neuropathic pain treatment. Fexofenadine, a histamine receptor 1 antagonist, is a clinical drug for the management of allergic reactions as well as pain and inflammation. However, the effect of fexofenadine on microglial activation and pain behaviors remains elucidated. Here, we investigated nanomedicinal approach that targets more preferentially microglia and long-term analgesics. Fexofenadine significantly abolished histamine-induced microglial activation. The fexofenadine-encapsulated poly(lactic-co-glycolic acid) nanoparticles (Fexo NPs) injection reduced the pain sensitivity of spinal nerve ligation rats in a dose-dependent manner. This alleviation was sustained for 4 days, whereas the effective period by direct fexofenadine injection was 3 h. Moreover, Fexo NPs inhibited microglial activation, inflammatory signaling, cytokine release, and a macrophage phenotype shift towards the alternative activated state in the spinal cord. These results show that Fexo NPs exhibit drug repositioning promise as a long-term treatment modality for neuropathic pain.


Assuntos
Nanopartículas , Neuralgia , Animais , Microglia , Neuralgia/genética , Ratos , Medula Espinal , Nervos Espinhais , Terfenadina/análogos & derivados
12.
PLoS Genet ; 15(2): e1007975, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30763314

RESUMO

Chemicals that are highly prevalent in our environment, such as phthalates and pesticides, have been linked to problems associated with reproductive health. However, rapid assessment of their impact on reproductive health and understanding how they cause such deleterious effects, remain challenging due to their fast-growing numbers and the limitations of various current toxicity assessment model systems. Here, we performed a high-throughput screen in C. elegans to identify chemicals inducing aneuploidy as a result of impaired germline function. We screened 46 chemicals that are widely present in our environment, but for which effects in the germline remain poorly understood. These included pesticides, phthalates, and chemicals used in hydraulic fracturing and crude oil processing. Of the 46 chemicals tested, 41% exhibited levels of aneuploidy higher than those detected for bisphenol A (BPA), an endocrine disruptor shown to affect meiosis, at concentrations correlating well with mammalian reproductive endpoints. We further examined three candidates eliciting aneuploidy: dibutyl phthalate (DBP), a likely endocrine disruptor and frequently used plasticizer, and the pesticides 2-(thiocyanomethylthio) benzothiazole (TCMTB) and permethrin. Exposure to these chemicals resulted in increased embryonic lethality, elevated DNA double-strand break (DSB) formation, activation of p53/CEP-1-dependent germ cell apoptosis, chromosomal abnormalities in oocytes at diakinesis, impaired chromosome segregation during early embryogenesis, and germline-specific alterations in gene expression. This study indicates that this high-throughput screening system is highly reliable for the identification of environmental chemicals inducing aneuploidy, and provides new insights into the impact of exposure to three widely used chemicals on meiosis and germline function.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Poluentes Ambientais/toxicidade , Células Germinativas/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Aneugênicos/toxicidade , Aneuploidia , Animais , Animais Geneticamente Modificados , Benzotiazóis/toxicidade , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/genética , Quebras de DNA de Cadeia Dupla , Dibutilftalato/toxicidade , Exposição Ambiental , Inseticidas/toxicidade , Meiose/efeitos dos fármacos , Permetrina/toxicidade , Plastificantes/toxicidade , Tiocianatos/toxicidade
13.
PLoS Genet ; 15(7): e1008252, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31283754

RESUMO

The biological roles of nucleic acid methylation, other than at the C5-position of cytosines in CpG dinucleotides, are still not well understood. Here, we report genetic evidence for a critical role for the putative DNA demethylase NMAD-1 in regulating meiosis in C. elegans. nmad-1 mutants have reduced fertility. They show defects in prophase I of meiosis, which leads to reduced embryo production and an increased incidence of males due to defective chromosomal segregation. In nmad-1 mutant worms, nuclear staging beginning at the leptotene and zygotene stages is disorganized, the cohesin complex is mislocalized at the diplotene and diakinesis stages, and chromosomes are improperly condensed, fused, or lost by the end of diakinesis. RNA sequencing of the nmad-1 germline revealed reduced induction of DNA replication and DNA damage response genes during meiosis, which was coupled with delayed DNA replication, impaired DNA repair and increased apoptosis of maturing oocytes. To begin to understand how NMAD-1 regulates DNA replication and repair, we used immunoprecipitation and mass spectrometry to identify NMAD-1 binding proteins. NMAD-1 binds to multiple proteins that regulate DNA repair and replication, including topoisomerase TOP-2 and co-localizes with TOP-2 on chromatin. Moreover, the majority of TOP-2 binding to chromatin depends on NMAD-1. These results suggest that NMAD-1 functions at DNA replication sites to regulate DNA replication and repair during meiosis.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Reparo do DNA , Replicação do DNA , Dioxigenases/genética , Oxirredutases N-Desmetilantes/genética , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/metabolismo , Segregação de Cromossomos , Dioxigenases/metabolismo , Masculino , Meiose , Mutação , Oxirredutases N-Desmetilantes/metabolismo , Análise de Sequência de RNA
14.
Epilepsy Behav ; 114(Pt A): 107609, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33257295

RESUMO

BACKGROUND: Prenatal stress increases the susceptibility of infants to seizures and is known to be associated with oxidative stress. Recent studies suggest that vitamin E has beneficial effects in various neurological diseases due to its antioxidant properties. In this study, we investigated the relationship between prenatal stress and vitamin E treatment on N-methyl-D-aspartate (NMDA)-induced spasms. METHODS: We used pregnant female Sprague Dawley rats and induced prenatal stress with an injection of betamethasone on G15. They were then treated orally with 200 mg/kg vitamin E or saline twice a day from G15-G21. On postnatal day 15, NMDA was administered to trigger spasms in offspring. The total number of spasms and latency to the first spasm were recorded. We also measured oxidative stress in the medial cortex using western blot, and calpain activity, thiobarbituric acid reactive substances (TBARS), glutathione (GSH)/GSH/glutathione disulfide (GSSG), superoxide dismutase (SOD) activity, catalase activity, and nitric oxide (NO) assays. RESULTS: We observed that rats treated with vitamin E while exposed to prenatal stress demonstrated reduced total number and frequency of spasms. Expression of glutamate decarboxylase 67 (GAD67) and K+/Cl- co-transporter (KCC2) were reduced after prenatal stress; this recovered in the vitamin E treated group. Further, expression of calpain 2 was decreased and various markers of oxidative stress (malondialdehyde (MDA), GSH/GSSG, SOD, catalase, and NO) were reduced in the vitamin E treated group. CONCLUSIONS: Our results provide evidence that vitamin E lowers oxidative stress and decreases seizure susceptibility in rat offspring exposed to prenatal stress. Given the well-known safety profile of vitamin E, these results indicate its potential as a strategy for preventing seizures.


Assuntos
Calpaína , Vitamina E , Animais , Antioxidantes , Catalase/metabolismo , Feminino , Glutationa/metabolismo , Estresse Oxidativo , Gravidez , Ratos , Ratos Sprague-Dawley , Espasmo , Superóxido Dismutase/metabolismo , Vitamina E/uso terapêutico
15.
Glia ; 68(5): 1065-1080, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31833596

RESUMO

Tonic extrasynaptic GABAA receptor (GABAA R) activation is under the tight control of tonic GABA release from astrocytes to maintain the brain's excitation/inhibition (E/I) balance; any slight E/I balance disturbance can cause serious pathological conditions including epileptic seizures. However, the pathophysiological role of tonic GABA release from astrocytes has not been tested in epileptic seizures. Here, we report that pharmacological or genetic intervention of the GABA-permeable Bestrophin-1 (Best1) channel prevented the generation of tonic GABA inhibition, disinhibiting CA1 pyramidal neuronal firing and augmenting seizure susceptibility in kainic acid (KA)-induced epileptic mice. Astrocyte-specific Best1 over-expression in KA-injected Best1 knockout mice fully restored the generation of tonic GABA inhibition and effectively suppressed seizure susceptibility. We demonstrate for the first time that tonic GABA from reactive astrocytes strongly contributes to the compensatory shift of E/I balance in epileptic hippocampi, serving as a good therapeutic target against altered E/I balance in epileptic seizures.


Assuntos
Astrócitos/metabolismo , Bestrofinas/metabolismo , Hipocampo/metabolismo , Inibição Neural/fisiologia , Convulsões/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Bestrofinas/genética , Ácido Caínico , Camundongos , Camundongos Knockout , Receptores de GABA-A/metabolismo , Convulsões/induzido quimicamente , Convulsões/genética
16.
Int J Mol Sci ; 21(7)2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32231148

RESUMO

Several studies have shown that brain and muscle aryl hydrocarbon receptor nuclear translocator-like 1 (BMAL1), an important molecule for maintaining circadian rhythms, inhibits the growth and metastasis of tumor cells in several types of cancer, including lung, colon, and breast cancer. However, its role in glioblastoma has not yet been established. Here, we addressed the function of BMAL1 in U87MG glioblastoma cells with two approaches-loss and gain of function. In the loss of function experiments, cell proliferation in U87MG cells transfected with small interfering RNA (siRNA) targeting BMAL1 was increased by approximately 24% (small interfering (si)-NC 0.91 ± 0.00 vs. si-BMAL1 1.129 ± 0.08) via upregulation of cyclin B1. In addition, cell migration and invasion of BMAL1 siRNA-treated glioblastoma cells were elevated by approximately 20% (si-NC 51.00 ± 1.53 vs. si-BMAL161.33 ± 0.88) and 209% (si-NC 21.28 ± 1.37 vs. si-BMAL1 44.47 ± 3.48), respectively, through the accumulation of phosphorylated-AKT (p-AKT) and matrix metalloproteinase (MMP)-9. Gain of function experiments revealed that adenovirus-mediated ectopic expression of BMAL1 in U87MG cells resulted in a 19% (Adenovirus (Ad)-vector 0.94± 0.03 vs. Ad-BMAL1 0.76 ± 0.03) decrease in cell proliferation compared with the control via downregulation of cyclin B1 and increased early and late apoptosis due to changes in the levels of BCL2-associated X protein (BAX), B-cell lymphoma 2 (BCL-2), and cleaved caspase-3. Likewise, cell migration and invasion were attenuated by approximately 24% (Ad-vector 55.00 ± 0.00 vs. Ad-BMAL1 41.83 ± 2.90) and 49% (Ad-vector 70.01 ± 1.24 vs. Ad-BMAL1 35.55 ± 1.78), respectively, in BMAL1-overexpressing U87MG cells following downregulation of p-AKT and MMP-9. Taken together, our results suggest that BMAL1 acts as an anti-cancer gene by altering the proliferation, migration, and invasion of glioblastoma cells. Therefore, the BMAL1 gene could be a potential therapeutic target in the treatment of glioblastoma.


Assuntos
Fatores de Transcrição ARNTL/metabolismo , Neoplasias Encefálicas/metabolismo , Ciclina B1/metabolismo , Glioblastoma/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição ARNTL/análise , Fatores de Transcrição ARNTL/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Ciclina B1/análise , Regulação para Baixo , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Metaloproteinase 9 da Matriz/análise , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/análise , Interferência de RNA
17.
Int J Mol Sci ; 20(18)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505901

RESUMO

Upon peripheral nerve injury, vesicular ATP is released from damaged primary afferent neurons. This extracellular ATP subsequently activates purinergic receptors of the spinal cord, which play a critical role in neuropathic pain. As an inhibitor of the vesicular nucleotide transporter (VNUT), Evans blue (EB) inhibits the vesicular storage and release of ATP in neurons. Thus, we tested whether EB could attenuate neuropathic pain behavior induced by spinal nerve ligation (SNL) in rats by targeting VNUT. An intrathecal injection of EB efficiently attenuated mechanical allodynia for five days in a dose-dependent manner and enhanced locomotive activity in an SNL rat model. Immunohistochemical analysis showed that EB was found in VNUT immunoreactivity on neurons in the dorsal root ganglion and the spinal dorsal horn. The level of ATP in cerebrospinal fluid in rats with SNL-induced neuropathic pain decreased upon administration of EB. Interestingly, EB blocked ATP release from neurons, but not glial cells in vitro. Eventually, the loss of ATP decreased microglial activity in the ipsilateral dorsal horn of the spinal cord, followed by a reduction in reactive oxygen species and proinflammatory mediators, such as interleukin (IL)-1ß and IL-6. Finally, a similar analgesic effect of EB was demonstrated in rats with monoiodoacetate-induced osteoarthritis (OA) pain. Taken together, these data demonstrate that EB prevents ATP release in the spinal dorsal horn and reduces the ATP/purinergic receptor-induced activation of spinal microglia followed by a decline in algogenic substances, thereby relieving neuropathic pain in rats with SNL.


Assuntos
Trifosfato de Adenosina/líquido cefalorraquidiano , Azul Evans/farmacologia , Neuralgia , Coluna Vertebral , Animais , Modelos Animais de Doenças , Gânglios Espinais/metabolismo , Gânglios Espinais/patologia , Gânglios Espinais/fisiopatologia , Interleucina-1beta/líquido cefalorraquidiano , Interleucina-6/líquido cefalorraquidiano , Masculino , Neuralgia/líquido cefalorraquidiano , Neuralgia/tratamento farmacológico , Neuralgia/patologia , Neuralgia/fisiopatologia , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Coluna Vertebral/metabolismo , Coluna Vertebral/patologia , Coluna Vertebral/fisiopatologia
18.
Biochem Biophys Res Commun ; 503(3): 1805-1811, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30072100

RESUMO

Isocitrate dehydrogenase 2 (IDH2) is an essential enzyme in the mitochondrial antioxidant system, which produces nicotinamide adenine dinucleotide phosphate, and thereby defends against oxidative stress. We have shown that IDH2 downregulation results in mitochondrial dysfunction and reactive oxygen species (ROS) generation in mouse endothelial cells. The redox enzyme p66shc is a key factor in regulating the level of ROS in endothelial cells. In this study, we hypothesized that IDH2 knockdown-induced mitochondrial dysfunction stimulates endothelial inflammation, which might be regulated by p66shc-mediated oxidative stress. Our results showed that IDH2 downregulation led to mitochondrial dysfunction by decreasing the expression of mitochondrial oxidative phosphorylation complexes I, II, and IV, reducing oxygen consumption, and depolarizing mitochondrial membrane potential in human umbilical vein endothelial cells (HUVECs). The dysfunction not only increased mitochondrial ROS levels but also activated p66shc expression in HUVECs and IDH2 knockout mice. IDH2 deficiency increased intercellular adhesion molecule (ICAM)-1 expression and mRNA levels of pro-inflammatory cytokines (tumor necrosis factor [TNF]-α, and interleukin [IL]-1ß) in HUVECs. The mRNA expression of ICAM-1 in endothelial cells and plasma levels of TNF-α and IL-1ß were also markedly elevated in IDH2 knockout mice. However, p66shc knockdown rescued IDH2 deficiency-induced mitochondrial ROS levels, monocyte adhesion, ICAM-1, TNF-α, and IL-1ß expression in HUVECs. These findings suggest that IDH2 deficiency induced endothelial inflammation via p66shc-mediated mitochondrial oxidative stress.


Assuntos
Células Endoteliais/metabolismo , Inflamação/metabolismo , Isocitrato Desidrogenase/deficiência , Mitocôndrias/metabolismo , Estresse Oxidativo , Animais , Células Cultivadas , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
19.
J Neuroinflammation ; 14(1): 189, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-28927423

RESUMO

BACKGROUND: The primary cilium is an organelle that can act as a master regulator of cellular signaling. Despite the presence of primary cilia in hippocampal neurons, their function is not fully understood. Recent studies have demonstrated that the primary cilium influences interleukin (IL)-1ß-induced NF-κB signaling, ultimately mediating the inflammatory response. We, therefore, investigated ciliary function and NF-κB signaling in lipopolysaccharide (LPS)-induced neuroinflammation in conjunction with ciliary length analysis. METHODS: Since TLR4/NF-κB signaling is a well-known inflammatory pathway, we measured ciliary length and inflammatory mediators in wild type (WT) and TLR4-/- mice injected with LPS. Next, to exclude the effects of microglial TLR4, we examined the ciliary length, ciliary components, inflammatory cytokine, and mediators in HT22 hippocampal neuronal cells. RESULTS: Primary ciliary length decreased in hippocampal pyramidal neurons after intracerebroventricular injection of LPS in WT mice, whereas it increased in TLR4-/- mice. LPS treatment decreased primary ciliary length, activated NF-κB signaling, and increased Cox2 and iNOS levels in HT22 hippocampal neurons. In contrast, silencing Kif3a, a key protein component of cilia, increased ARL13B ciliary protein levels and suppressed NF-κB signaling and expression of inflammatory mediators. CONCLUSIONS: These data suggest that LPS-induced NF-κB signaling and inflammatory mediator expression are modulated by cilia and that the blockade of primary cilium formation by Kif3a siRNA regulates TLR4-induced NF-κB signaling. We propose that primary cilia are critical for regulating NF-κB signaling events in neuroinflammation and in the innate immune response.


Assuntos
Cílios/imunologia , Hipocampo/imunologia , Inflamação/imunologia , Neurônios/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Cílios/metabolismo , Cílios/ultraestrutura , Hipocampo/metabolismo , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Neurônios/metabolismo , Transdução de Sinais/imunologia , Receptor 4 Toll-Like/metabolismo
20.
PLoS Biol ; 12(7): e1001915, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25072732

RESUMO

Conflict between the sexes over reproductive interests can drive rapid evolution of reproductive traits and promote speciation. Here we show that inter-species mating between Caenorhabditis nematodes sterilizes maternal individuals. The principal effectors of male-induced harm are sperm cells, which induce sterility and shorten lifespan by displacing conspecific sperm, invading the ovary, and sometimes breaching the gonad to infiltrate other tissues. This sperm-mediated harm is pervasive across species, but idiosyncrasies in its magnitude implicate both independent histories of sexually antagonistic coevolution within species and differences in reproductive mode (self-fertilizing hermaphrodites versus females) in determining its severity. Consistent with this conclusion, in androdioecious species the hermaphrodites are more vulnerable, the males more benign, or both. Patterns of assortative mating and a low incidence of invasive sperm occurring with conspecific mating are indicative of ongoing intra-specific sexual conflict that results in inter-species reproductive incompatibility.


Assuntos
Caenorhabditis/fisiologia , Reprodução/fisiologia , Isolamento Reprodutivo , Espermatozoides/fisiologia , Animais , Feminino , Organismos Hermafroditas/fisiologia , Infertilidade/etiologia , Inseminação , Masculino , Comportamento Sexual Animal , Especificidade da Espécie
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