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1.
EMBO J ; 41(1): e108813, 2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-34817085

RESUMO

Heterochromatin is a conserved feature of eukaryotic chromosomes, with central roles in gene expression regulation and maintenance of genome stability. How heterochromatin proteins regulate DNA repair remains poorly described. In the yeast Saccharomyces cerevisiae, the silent information regulator (SIR) complex assembles heterochromatin-like chromatin at sub-telomeric chromosomal regions. SIR-mediated repressive chromatin limits DNA double-strand break (DSB) resection, thus protecting damaged chromosome ends during homologous recombination (HR). As resection initiation represents the crossroads between repair by non-homologous end joining (NHEJ) or HR, we asked whether SIR-mediated heterochromatin regulates NHEJ. We show that SIRs promote NHEJ through two pathways, one depending on repressive chromatin assembly, and the other relying on Sir3 in a manner that is independent of its heterochromatin-promoting function. Via physical interaction with the Sae2 protein, Sir3 impairs Sae2-dependent functions of the MRX (Mre11-Rad50-Xrs2) complex, thereby limiting Mre11-mediated resection, delaying MRX removal from DSB ends, and promoting NHEJ.


Assuntos
Reparo do DNA por Junção de Extremidades , Endonucleases/metabolismo , Heterocromatina/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Endonucleases/química , Mutação Puntual/genética , Ligação Proteica , Domínios Proteicos , Proteínas de Saccharomyces cerevisiae/química , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/química , Proteínas Reguladoras de Informação Silenciosa de Saccharomyces cerevisiae/genética , Telômero/metabolismo
2.
Am J Physiol Endocrinol Metab ; 327(1): E1-E12, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38690939

RESUMO

High levels of testosterone (Testo) are associated with cardiovascular risk by increasing reactive oxygen species (ROS) formation. NADPH oxidases (NOX) are the major source of ROS in the vasculature of cardiovascular diseases. NOX4 is a unique isotype, which produces hydrogen peroxide (H2O2), and its participation in cardiovascular biology is controversial. So far, it is unclear whether NOX4 protects from Testo-induced endothelial injury. Thus, we hypothesized that supraphysiological levels of Testo induce endothelial NOX4 expression to attenuate endothelial injury. Human mesenteric vascular endothelial cells (HMECs) and human umbilical vein endothelial cells (HUVEC) were treated with Testo (10-7 M) with or without a NOX4 inhibitor [GLX351322 (10-4 M)] or NOX4 siRNA. In vivo, 10-wk-old C57Bl/6J male mice were treated with Testo (10 mg/kg) for 30 days to study endothelial function. Testo increased mRNA and protein levels of NOX4 in HMECs and HUVECs. Testo increased superoxide anion (O2-) and H2O2 production, which were abolished by NOX1 and NOX4 inhibition, respectively. Testo also attenuated bradykinin-induced NO production, which was further impaired by NOX4 inhibition. In vivo, Testo decreased H2O2 production in aortic segments and triggered endothelial dysfunction [decreased relaxation to acetylcholine (ACh)], which was further impaired by GLX351322 and by a superoxide dismutase and catalase mimetic (EUK134). Finally, Testo led to a dysregulated endothelial cell migration, which was exacerbated by GLX351322. These data indicate that supraphysiological levels of Testo increase the endothelial expression and activity of NOX4 to counterbalance the deleterious effects caused by Testo in endothelial function.NEW & NOTEWORTHY By inducing ROS formation, high levels of testosterone play a major role in the pathogenesis of cardiovascular disease. NOXs are the major sources of ROS in the vasculature of cardiovascular diseases. Herein, we describe a novel compensatory mechanism by showing that NOX4 is a protective oxidant enzyme and counterbalances the deleterious effects of testosterone in endothelial cells by modulating hydrogen peroxide formation.


Assuntos
Movimento Celular , Endotélio Vascular , Células Endoteliais da Veia Umbilical Humana , Peróxido de Hidrogênio , Camundongos Endogâmicos C57BL , NADPH Oxidase 4 , Testosterona , Animais , Humanos , Masculino , Camundongos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células Endoteliais/metabolismo , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacologia , NADPH Oxidase 4/metabolismo , NADPH Oxidase 4/genética , Espécies Reativas de Oxigênio/metabolismo , Testosterona/farmacologia , Testosterona/metabolismo
3.
Am J Physiol Endocrinol Metab ; 326(5): E555-E566, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38446637

RESUMO

Prenatal exposure to maternal diabetes has been recognized as a significant cardiovascular risk factor, increasing the susceptibility to the emergence of conditions such as high blood pressure, atherosclerosis, and heart disease in later stages of life. However, it is unclear if offspring exposed to diabetes in utero have worse vascular outcomes on a high-salt (HS) diet. To test the hypothesis that in utero exposure to maternal diabetes predisposes to HS-induced vascular dysfunction, we treated adult male wild-type offspring (DM_Exp, 6 mo old) of diabetic Ins2+/C96Y mice (Akita mice) with HS (8% sodium chloride, 10 days) and analyzed endothelial function via wire myograph and cyclooxygenase (COX)-derived prostanoids pathway by ELISA, quantitative PCR, and immunochemistry. On a regular diet, DM_Exp mice did not manifest any vascular dysfunction, remodeling, or inflammation. However, HS increased aortic contractility to phenylephrine and induced endothelial dysfunction (analyzed by acetylcholine-induced endothelium-dependent relaxation), vascular hydrogen peroxide production, COX2 expression, and prostaglandin E2 (PGE2) overproduction. Interestingly, ex vivo antioxidant treatment (tempol) or COX1/2 (indomethacin) or COX2 (NS398) inhibitors improved or reverted the endothelial dysfunction in DM_Exp mice fed a HS diet. Finally, DM_Exp mice fed with HS exhibited greater circulating cytokines and chemokines accompanied by vascular inflammation. In summary, our findings indicate that prenatal exposure to maternal diabetes predisposes to HS-induced vascular dysfunction, primarily through the induction of oxidative stress and the generation of COX2-derived PGE2. This supports the concept that in utero exposure to maternal diabetes is a cardiovascular risk factor in adulthood.NEW & NOTEWORTHY Using a unique mouse model of prenatal exposure to maternal type 1 diabetes, our study demonstrates the novel observation that prenatal exposure to maternal diabetes results in a predisposition to high-salt (HS) dietary-induced vascular dysfunction and inflammation in adulthood. Mechanistically, we demonstrated that in utero exposure to maternal diabetes and HS intake induces vascular oxidative stress, cyclooxygenase-derived prostaglandin E2, and inflammation.


Assuntos
Diabetes Gestacional , Endotélio Vascular , Efeitos Tardios da Exposição Pré-Natal , Prostaglandinas , Animais , Feminino , Camundongos , Gravidez , Ciclo-Oxigenase 2/metabolismo , Diabetes Gestacional/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Inflamação/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Prostaglandinas/metabolismo , Cloreto de Sódio na Dieta/efeitos adversos , Cloreto de Sódio na Dieta/metabolismo
4.
Bioinformatics ; 39(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36661327

RESUMO

SUMMARY: Here, we present sbml2hyb, an easy-to-use standalone Python tool that facilitates the conversion of existing mechanistic models of biological systems in Systems Biology Markup Language (SBML) into hybrid semiparametric models that combine mechanistic functions with machine learning (ML). The so-formed hybrid models can be trained and stored back in databases in SBML format. The tool supports a user-friendly export interface with an internal format validator. Two case studies illustrate the use of the sbml2hyb tool. Additionally, we describe HMOD, a new model format designed to support and facilitate hybrid models building. It aggregates the mechanistic model information with the ML information and follows as close as possible the SBML rules. We expect the sbml2hyb tool and HMOD to greatly facilitate the widespread usage of hybrid modeling techniques for biological systems analysis. AVAILABILITY AND IMPLEMENTATION: The Python interface, source code and the example models used for the case studies are accessible at: https://github.com/r-costa/sbml2hyb. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
Linguagens de Programação , Biologia de Sistemas , Biologia de Sistemas/métodos , Modelos Biológicos , Software , Idioma
5.
Cytokine ; 176: 156503, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38301358

RESUMO

Orosomucoid, or alpha-1 acid glycoprotein (AGP), is a major acute-phase protein expressed in response to systemic injury and inflammation. AGP has been described as an inhibitor of neutrophil migration on sepsis, particularly its immunomodulation effects. AGP's biological functions in coronavirus disease 2019 (COVID-19) are not understood. We sought to investigate the role of AGP in severe COVID-19 infection patients and neutrophils infected with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Epidemiological data, AGP levels, and other laboratory parameters were measured in blood samples from 56 subjects hospitalized in the ICU with SARS-CoV-2 infection. To evaluate the role of AGP in NETosis in neutrophils, blood samples from health patients were collected, and neutrophils were separated and infected with SARS-CoV-2. Those neutrophils were treated with AGP or vehicle, and NETosis was analyzed by flow cytometry. AGP was upregulated in severe COVID-19 patients (p<0.05). AGP level was positively correlated with IL-6 and C-reactive protein (respectively, p=0.005, p=0.002) and negatively correlated with lactate (p=0.004). AGP treatment downregulated early and late NETosis (respectively, 35.7% and 43.5%) in neutrophils infected with SARS-CoV-2 and up-regulated IL-6 supernatant culture expression (p<0.0001). Our data showed increased AGP in COVID-19 infection and contributed to NETosis regulation and increased IL-6 production, possibly related to the Cytokine storm in COVID-19.


Assuntos
COVID-19 , Humanos , COVID-19/metabolismo , Neutrófilos/metabolismo , Orosomucoide/metabolismo , Orosomucoide/farmacologia , SARS-CoV-2 , Interleucina-6/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Imunoproteínas/metabolismo
6.
Biotechnol Bioeng ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38859573

RESUMO

The increasing prevalence of omics data sources is pushing the study of regulatory mechanisms underlying complex diseases such as cancer. However, the vast quantities of molecular features produced and the inherent interplay between them lead to a level of complexity that hampers both descriptive and predictive tasks, requiring custom-built algorithms that can extract relevant information from these sources of data. We propose a transformation that moves data centered on molecules (e.g., transcripts and proteins) to a new data space focused on putative regulatory modules given by statistically relevant co-expression patterns. To this end, the proposed transformation extracts patterns from the data through biclustering and uses them to create new variables with guarantees of interpretability and discriminative power. The transformation is shown to achieve dimensionality reductions of up to 99% and increase predictive performance of various classifiers across multiple omics layers. Results suggest that omics data transformations from gene-centric to pattern-centric data supports both prediction tasks and human interpretation, notably contributing to precision medicine applications.

7.
Med Mycol ; 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38970370

RESUMO

Differently from immunocompromised patients, very little information is available in the literature regarding the clinical presentation, epidemiology, and outcomes of histoplasmosis in non-immunosuppressed individuals living in endemic areas. This retrospective case series study was carried out by reviewing the medical records of non-immunocompromised patients with histoplasmosis, residents in a hyperendemic area in northeastern Brazil, between 2011 and 2022. Thirty HIV-negative patients were identified with histoplasmosis, and 19 cases met the inclusion criteria: ten patients had acute pulmonary histoplasmosis (APH), one had chronic pulmonary histoplasmosis (CPH), two had progressive disseminated (PD) presentation, and six had the chronic disseminated (CD) form. The median age of our sample was 32.7 years old [IQR: 24 - 45]. Most of the patients were male (male-to-female ratio=15:4) and resided in the state capital (n=9). The majority had a previous history of exposure to well-known risk factors for Histoplasma infection. The lung images of APH were characterized by nodules, enlarged hilar/mediastinal lymph nodes, and patches, and three patients were initially treated empirically for pulmonary tuberculosis; one death was registered. The chronic pulmonary form of histoplasmosis was diagnosed in one patient only after the symptoms persisted despite specific treatment. The primary clinical manifestations of the CD form were enlarged lymph nodes, with histopathology being the main diagnostic method. The cases were detected as isolated occurrences and not as an outbreak, suggesting that exposure to Histoplasma can be more widespread than presumed. Despite the self-limiting nature of the disease, death can occur even in previously heath patients.


This study aimed to describe the presentation of histoplasmosis outside the context of immunosuppression, including the diagnostic methods, epidemiology, and main radiological and clinical features. A better understanding of the various forms of this disease will help improve case management.

8.
Brain ; 146(6): 2346-2363, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36511898

RESUMO

Polyglutamine diseases are a group of neurodegenerative disorders caused by an abnormal expansion of CAG repeat tracts in the codifying regions of nine, otherwise unrelated, genes. While the protein products of these genes are suggested to play diverse cellular roles, the pathogenic mutant proteins bearing an expanded polyglutamine sequence share a tendency to self-assemble, aggregate and engage in abnormal molecular interactions. Understanding the shared paths that link polyglutamine protein expansion to the nervous system dysfunction and the degeneration that takes place in these disorders is instrumental to the identification of targets for therapeutic intervention. Among polyglutamine diseases, spinocerebellar ataxias (SCAs) share many common aspects, including the fact that they involve dysfunction of the cerebellum, resulting in ataxia. Our work aimed at exploring a putative new therapeutic target for the two forms of SCA with higher worldwide prevalence, SCA type 2 (SCA2) and type 3 (SCA3), which are caused by expanded forms of ataxin-2 (ATXN2) and ataxin-3 (ATXN3), respectively. The pathophysiology of polyglutamine diseases has been described to involve an inability to properly respond to cell stress. We evaluated the ability of GTPase-activating protein-binding protein 1 (G3BP1), an RNA-binding protein involved in RNA metabolism regulation and stress responses, to counteract SCA2 and SCA3 pathology, using both in vitro and in vivo disease models. Our results indicate that G3BP1 overexpression in cell models leads to a reduction of ATXN2 and ATXN3 aggregation, associated with a decrease in protein expression. This protective effect of G3BP1 against polyglutamine protein aggregation was reinforced by the fact that silencing G3bp1 in the mouse brain increases human expanded ATXN2 and ATXN3 aggregation. Moreover, a decrease of G3BP1 levels was detected in cells derived from patients with SCA2 and SCA3, suggesting that G3BP1 function is compromised in the context of these diseases. In lentiviral mouse models of SCA2 and SCA3, G3BP1 overexpression not only decreased protein aggregation but also contributed to the preservation of neuronal cells. Finally, in an SCA3 transgenic mouse model with a severe ataxic phenotype, G3BP1 lentiviral delivery to the cerebellum led to amelioration of several motor behavioural deficits. Overall, our results indicate that a decrease in G3BP1 levels may be a contributing factor to SCA2 and SCA3 pathophysiology, and that administration of this protein through viral vector-mediated delivery may constitute a putative approach to therapy for these diseases, and possibly other polyglutamine disorders.


Assuntos
Doença de Machado-Joseph , Ataxias Espinocerebelares , Humanos , Camundongos , Animais , DNA Helicases/metabolismo , Proteínas de Choque Térmico , Agregados Proteicos , Grânulos de Estresse , Proteínas de Ligação a Poli-ADP-Ribose/genética , RNA Helicases/genética , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/genética , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/patologia , Ataxina-3/genética , Camundongos Transgênicos , Doença de Machado-Joseph/genética
9.
BMC Public Health ; 24(1): 1080, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637757

RESUMO

Movement-related behaviors (physical activity [PA], sedentary behavior [SB], and sleep) and diet interact with each other and play important roles in health indicators in youth. This systematic review aimed to investigate how PA, SB, sleep, and diet cluster in youth by biological sex; and to examine which cluster are associated with health indicators. This study was registered in PROSPERO (number: CRD42018094826). Five electronic databases were assessed. Eligibility criteria allowed studies that included youth (aged 19 years and younger), and only the four behaviors {PA, SB, sleep, and diet (ultra-processed foods [UPF]; fruits and vegetables [FV])} analyzed by applying data-based cluster procedures. From 12,719 articles screened; 23 were included. Of these, four investigated children, and ten identified clusters by biological sex. Sixty-six mixed cluster were identified including, 34 in mixed-sex samples, 10 in boys and 11 in girls. The most frequent clusters in mixed-sex samples were "High SB UPF Low Sleep", "Low PA High SB Satisfactory Sleep", and "High PA". The main difference in profiles according to sex was that girls' clusters were characterized by high sleep duration, whereas boys' clusters by high PA. There were a few associations found between cluster types and health indicators, highlighting that youth assigned to cluster types with low PA exhibited higher adiposity. In conclusion, the youth presented a range of clusters of behaviors, typically exhibiting at least one unhealthy behavior. Similar patterns were observed in both sexes with the biggest difference in time of sleep for girls and PA for boys. These findings underscore the importance of intervention strategies targeting multiple behaviors simultaneously to enhance health risk profiles and indicators in children and adolescents.


Assuntos
Dieta , Exercício Físico , Obesidade , Comportamento Sedentário , Adolescente , Criança , Feminino , Humanos , Masculino , Comportamentos Relacionados com a Saúde , Atividade Motora , Sono
10.
Behav Sleep Med ; 22(2): 129-139, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-37154038

RESUMO

OBJECTIVES: This cross-sectional study aimed to examine the relationships of sleep timing and sleep variability with depressive symptoms, health-related quality of life (HRQoL), daytime sleepiness, and body mass index (BMI) in adolescents. METHODS: Adolescents from three schools (n = 571, 56% female, 16.3 ± 1.0 years) had their sleep examined by actigraphy, their anthropometrics assessed, and answered a survey. Sleep timing was examined by combining groups of median-dichotomized onset and wakeup times (early onset and early wakeup; early onset and late wakeup; later onset and early wakeup; later onset and later wakeup); sleep variability was based on within-participant standard deviations of onset and wakeup; and sleep duration as the length of time between onset and wakeup. The sleep variables were separated for weekdays and weekend. Mixed linear models were fitted to compare each sleep variable with health-related outcomes. RESULTS: Higher values of daytime sleepiness were observed in adolescents from the late-early and late-late timing group during the week. Greater sleep midpoint and wakeup variability on weekdays were related with higher daytime sleepiness. Adolescents in the late-late and early-late groups showed higher daytime sleepiness. Increased of all sleep variability variables was related with greater daytime sleepiness. Higher depressive symptoms scores were found among adolescents in the late-early subgroup and with the increase of sleep variability. Participants with greater sleep onset variability and sleep midpoint variability reported less HRQoL. CONCLUSIONS: Not only sleep duration, but sleep timing and variability also relate to health outcomes, and should be addressed by policies and interventions among adolescents.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Qualidade de Vida , Humanos , Feminino , Adolescente , Masculino , Estudos Transversais , Brasil/epidemiologia , Sono , Distúrbios do Sono por Sonolência Excessiva/epidemiologia
11.
J Cell Mol Med ; 27(1): 1-14, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36515571

RESUMO

In the present study, we hypothesized that endothelin (ET) receptors (ETA and ETB ) stimulation, through increased calcium and ROS formation, leads to Nucleotide Oligomerization Domain-Like Receptor Family, Pyrin Domain Containing 3 (NLRP3) activation. Intracavernosal pressure (ICP/MAP) was measured in C57BL/6 (WT) mice. Functional and immunoblotting assays were performed in corpora cavernosa (CC) strips from WT, NLRP3-/- and caspase-/- mice in the presence of ET-1 (100 nM) and vehicle, MCC950, tiron, BAPTA AM, BQ123, or BQ788. ET-1 reduced the ICP/MAP in WT mice, and MCC950 prevented the ET-1 effect. ET-1 decreased CC ACh-, sodium nitroprusside (SNP)-induced relaxation, and increased caspase-1 expression. BQ123 an ETA receptor antagonist reversed the effect. The ETB receptor antagonist BQ788 also reversed ET-1 inhibition of ACh and SNP relaxation. Additionally, tiron, BAPTA AM, and NLRP3 genetic deletion prevented the ET-1-induced loss of ACh and SNP relaxation. Moreover, BQ123 diminished CC caspase-1 expression, while BQ788 increased caspase-1 and IL-1ß levels in a concentration-dependent manner (100 nM-10 µM). Furthermore, tiron and BAPTA AM prevented ET-1-induced increase in caspase-1. In addition, BAPTA AM blocked ET-1-induced ROS generation. In conclusion, ET-1-induced erectile dysfunction depends on ETA - and ETB -mediated activation of NLRP3 in mouse CC via Ca2+ -dependent ROS generation.


Assuntos
Endotelina-1 , Disfunção Erétil , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Masculino , Camundongos , Sal Dissódico do Ácido 1,2-Di-Hidroxibenzeno-3,5 Dissulfônico , Antagonistas dos Receptores de Endotelina , Endotelina-1/metabolismo , Disfunção Erétil/metabolismo , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio , Receptores de Endotelina
12.
Plant J ; 109(5): 1213-1228, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34897855

RESUMO

In monoecious melon (Cucumis melo), sex is determined by the differential expression of sex determination genes (SDGs) and adoption of sex-specific transcriptional programs. Histone modifications such as H3K27me3 have been previously shown to be a hallmark associated to unisexual flower development in melon; yet, no genetic approaches have been conducted for elucidating the roles of H3K27me3 writers, readers, and erasers in this process. Here we show that melon homologs to Arabidopsis LHP1, CmLHP1A and B, redundantly control several aspects of plant development, including sex expression. Cmlhp1ab double mutants displayed an overall loss and redistribution of H3K27me3, leading to a deregulation of genes involved in hormone responses, plant architecture, and flower development. Consequently, double mutants display pleiotropic phenotypes and, interestingly, a general increase of the male:female ratio. We associated this phenomenon with a general deregulation of some hormonal response genes and a local activation of male-promoting SDGs and MADS-box transcription factors. Altogether, these results reveal a novel function for CmLHP1 proteins in maintenance of monoecy and provide novel insights into the polycomb-mediated epigenomic regulation of sex lability in plants.


Assuntos
Arabidopsis , Cucumis melo , Cucurbitaceae , Arabidopsis/genética , Cucumis melo/genética , Cucumis melo/metabolismo , Cucurbitaceae/genética , Regulação da Expressão Gênica de Plantas/genética , Histonas/metabolismo , Desenvolvimento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
Am J Physiol Heart Circ Physiol ; 325(2): H252-H263, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37327001

RESUMO

The cytokine storm in SARS-CoV-2 infection contributes to the onset of inflammation and target-organ damage. The endothelium is a key player in COVID-19 pathophysiology and it is an important target for cytokines. Considering that cytokines trigger oxidative stress and negatively impact endothelial cell function, we sought to determine whether serum from individuals with severe COVID-19 decreases endothelial cells' main antioxidant defense, i.e., the antioxidant transcriptional factor Nrf2. Human umbilical vein endothelial cells (HUVECs) were incubated with serum from patients with severe COVID-19 at different time points and the effects on redox balance and Nrf2 activity were determined. Serum from individuals with COVID-19 increased oxidant species, as indicated by higher DHE (dihydroethydine) oxidation, increased protein carbonylation, and induced mitochondrial reactive oxygen species (ROS) generation and dysfunction. Serum from patients with COVID-19, but not serum from healthy individuals, induced cell death and diminished nitric oxide (NO) bioavailability. In parallel, Nrf2 nuclear accumulation and the expression of Nrf2-targeted genes were decreased in endothelial cells exposed to serum from individuals with COVID-19. In addition, these cells exhibited higher expression of Bach-1, a negative regulator of Nrf2 that competes for DNA binding. All events were prevented by tocilizumab, an IL-6 receptor blocker, indicating that IL-6 is key to the impairment of endothelial antioxidant defense. In conclusion, endothelial dysfunction related to SARS-CoV-2 infection is linked to decreased endothelial antioxidant defense via IL-6-dependent mechanisms. Pharmacological activation of Nrf2 may decrease endothelial cell damage in individuals with severe COVID-19.NEW & NOTEWORTHY We demonstrate that endothelial cell dysfunction in SARS-CoV-2-infected individuals is linked to decreased activity of the major antioxidant system regulator, the Nrf2 transcription factor. We provide evidence that this phenomenon relies on IL-6, an important cytokine involved in the pathophysiology of COVID-19. Our data support the view that Nrf2 activation is a potential therapeutical strategy to prevent oxidative stress and vascular inflammation in severe cases of COVID-19.


Assuntos
Antioxidantes , COVID-19 , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Regulação para Baixo , Síndrome da Liberação de Citocina , Interleucina-6/metabolismo , Células Cultivadas , SARS-CoV-2/metabolismo , Estresse Oxidativo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Citocinas/metabolismo
14.
Am J Physiol Regul Integr Comp Physiol ; 324(4): R435-R445, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36737252

RESUMO

Coronavirus disease 2019 (COVID-19) infection has a negative impact on the cytokine profile of pregnant women. Increased levels of proinflammatory cytokines seem to be correlated with the severity of the disease, in addition to predisposing to miscarriage or premature birth. Proinflammatory cytokines increase the generation of reactive oxygen species (ROS). It is unclear how interleukin-6 (IL-6) found in the circulation of patients with severe COVID-19 might affect gestational health, particularly concerning umbilical cord function. This study tested the hypothesis that IL-6 present in the circulation of women with severe COVID-19 causes umbilical cord artery dysfunction by increasing ROS generation and activating redox-sensitive proteins. Umbilical cord arteries were incubated with serum from healthy women and women with severe COVID-19. Vascular function was assessed using concentration-effect curves to serotonin in the presence or absence of pharmacological agents, such as tocilizumab (antibody against the IL-6 receptor), tiron (ROS scavenger), ML171 (Nox1 inhibitor), and Y27632 (Rho kinase inhibitor). ROS generation was assessed by the dihydroethidine probe and Rho kinase activity by an enzymatic assay. Umbilical arteries exposed to serum from women with severe COVID-19 were hyperreactive to serotonin. This effect was abolished in the presence of tocilizumab, tiron, ML171, and Y27632. In addition, serum from women with severe COVID-19 increased Nox1-dependent ROS generation and Rho kinase activity. Increased Rho kinase activity was abolished by tocilizumab and tiron. Serum cytokines in women with severe COVID-19 promote umbilical artery dysfunction. IL-6 is key to Nox-linked vascular oxidative stress and activation of the Rho kinase pathway.


Assuntos
COVID-19 , Interleucina-6 , Feminino , Humanos , Gravidez , Sal Dissódico do Ácido 1,2-Di-Hidroxibenzeno-3,5 Dissulfônico , Artérias/metabolismo , Citocinas , Espécies Reativas de Oxigênio/metabolismo , Quinases Associadas a rho , Serotonina , Cordão Umbilical
15.
Ann Neurol ; 92(3): 400-410, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35688801

RESUMO

OBJECTIVE: Rehabilitation top-down techniques based on brain stimulation present variable outcomes in unilateral spatial neglect (USN) after stroke. This study aimed to examine the effects of physical therapy after anodal and cathodal transcranial direct current stimulation (A-tDCS and C-tDCS, respectively) to improve visuospatial and functional impairments in individuals with USN after stroke. METHODS: This double-blinded, pilot randomized clinical trial enrolled patients with USN after ischemic stroke. Randomization was stratified according to the Behavior Inattention Test-Conventional (BIT-C) and Catherine Bergego Scale (CBS). Outpatient physical therapy was conducted for 7.5 weeks after 20 minutes of tDCS. The primary outcome was the USN degree evaluated by the BIT-C. Secondary outcomes were the difference in CBS score, stroke severity (National Institutes of Health Stroke Scale [NIHSS]), disability (modified Rankin Scale), autonomy (Barthel Index, Functional Independence Measure), and quality of life (EuroQol Group 5-Dimension Self-Report Questionnaire). Outcomes were analyzed using an analysis of covariance model corrected by age, baseline NIHSS, and baseline BIT-C. Pairwise post hoc comparisons were performed using Bonferroni correction. RESULTS: In the primary outcomes, A-tDCS led to greater improvement in BIT-C after intervention (mean difference [MD] = 18.4, 95% confidence interval [CI] = 3.9-32.8, p = 0.008) compared to sham. However, no significant differences were observed between A-tDCS and C-tDCS (MD = 13.9, 95% CI = -0.3 to 28.1, p = 0.057), or C-tDCS and sham (MD = 4.5, 95% CI = -9.7 to 18.8, p = 0.99). There were no significant differences between groups in terms of secondary outcomes. INTERPRETATION: A-tDCS associated with physical therapy can decrease the severity of USN after stroke. However, these preliminary findings must be confirmed by collecting additional evidence in a larger phase 3 trial. ANN NEUROL 2022;92:400-410.


Assuntos
Transtornos da Percepção , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Encéfalo , Humanos , Transtornos da Percepção/etiologia , Transtornos da Percepção/terapia , Qualidade de Vida , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/terapia , Estimulação Transcraniana por Corrente Contínua/métodos , Resultado do Tratamento
16.
Qual Life Res ; 32(7): 2089-2098, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36856892

RESUMO

PURPOSE: To investigate the independent and joint associations of cardiorespiratory fitness and body mass index (BMI) with five dimensions of Health-Related Quality of Life (HRQoL) in a cross-sectional sample of Brazilian adolescents. METHODS: 619 Brazilian schoolchildren answered a survey, BMI categories (healthy weight and overweight/obesity) were assessed by their weight and height, and they participated in a 20-m shuttle run test. HRQoL was measured using the KIDSCREEN-27 across five dimensions: Physical Well-Being, Psychological Well-Being, Autonomy and Parent Relation, Peers and Social Support, and School Environment. Sex, age, maternal education, physical activity level, and habitual sedentary behaviour were assessed and used as adjusting variables. Cardiorespiratory fitness was categorized in tertiles and independent and joint associations were tested using mixed-effects linear regressions. RESULTS: Higher levels of cardiorespiratory fitness were favourably associated with the physical well-being, psychological well-being, and peer and social support dimensions of HRQoL. Adolescents with overweight/obesity presented higher scores on peer and social support dimensions when compared to healthy-weight adolescents. Independent of the adolescents' BMI categories, better cardiorespiratory fitness was positively associated with physical and psychological well-being when compared with the category of overweight/obesity and low cardiorespiratory fitness. In addition, adolescents with overweight/obesity combined with intermediate cardiorespiratory fitness or high cardiorespiratory fitness had higher scores on the peer and social support dimension. CONCLUSION: Cardiorespiratory fitness is a strong correlate of HRQoL across most of the dimensions measured, while BMI was a correlate of one dimension of HRQoL. Future studies should evaluate these relationships prospectively and experimentally.


Assuntos
Aptidão Cardiorrespiratória , Humanos , Adolescente , Criança , Sobrepeso/psicologia , Qualidade de Vida/psicologia , Estudos Transversais , Brasil , Obesidade/psicologia , Índice de Massa Corporal , Aptidão Física
17.
An Acad Bras Cienc ; 95(suppl 1): e20220532, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37556713

RESUMO

This study evaluated the technological viability of yogurt with the addition of green-banana biomass (Musa spp.) considering the resistant starch (BBV) as a potential prebiotic ingredient and texture agent. Four yogurt formulations were prepared: control; 3% BBV; 5% BBV; and 10% BBV. They were subjected to analysis of resistant starch, lactose, fat, total dry extract, defatted dry extract, moisture, ash, proteins, pH and titratable acidity; syneresis analysis, instrumental texture and instrumental color. All four formulations met the requirements of the identity and quality regulation for fermented milks regarding the physicochemical and microbiological parameters. In the instrumental color analysis, in all treatments with added BBV, darkening was observed after 21 days, with a reduction of a* coordinate and an increase of b* coordinate. In the instrumental texture analysis, the yogurt in the Control treatment had the highest firmness (0.430 N) at 21 days among these treatments. Among the treatments with added BBV, the yogurt with 5% added BBV showed the best results for increasing the viability of lactic bacteria. It was found that yogurt with added BBV is a promising alternative in the elaboration of functional dairy products, adding value to the banana production chain by reducing the green fruit waste.


Assuntos
Musa , Prebióticos , Biomassa , Prebióticos/análise , Amido Resistente/análise , Iogurte/análise
18.
Radiologia ; 2023 Jan 31.
Artigo em Espanhol | MEDLINE | ID: mdl-36744156

RESUMO

OBJECTIVE: Rapid progression of COVID-19 pneumonia may put patients at risk of requiring ventilatory support, such as non-invasive mechanical ventilation or endotracheal intubation. Implementing tools that detect COVID-19 pneumonia can improve the patient's healthcare. We aim to evaluate the efficacy and efficiency of the artificial intelligence (AI) tool GE Healthcare's Thoracic Care Suite (featuring Lunit INSIGHT CXR, TCS) to predict the ventilatory support need based on pneumonic progression of COVID-19 on consecutive chest X-rays. METHODS: Outpatients with confirmed SARS-CoV-2 infection, with chest X-ray (CXR) findings probable or indeterminate for COVID-19 pneumonia, who required a second CXR due to unfavorable clinical course, were collected. The number of affected lung fields for the two CXRs was assessed using the AI tool. RESULTS: One hundred fourteen patients (57.4 ± 14.2 years, 65 -57%- men) were retrospectively collected. Fifteen (13.2%) required ventilatory support. Progression of pneumonic extension ≥ 0.5 lung fields per day compared to pneumonia onset, detected using the TCS tool, increased the risk of requiring ventilatory support by 4-fold. Analyzing the AI output required 26 seconds of radiological time. CONCLUSIONS: Applying the AI tool, Thoracic Care Suite, to CXR of patients with COVID-19 pneumonia allows us to anticipate ventilatory support requirements requiring less than half a minute.

19.
Eur Radiol ; 32(5): 3490-3500, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35034140

RESUMO

OBJECTIVES: Identifying early markers of poor prognosis of coronavirus disease 2019 (COVID-19) is mandatory. Our purpose is to analyze by chest radiography if rapid worsening of COVID-19 pneumonia in the initial days has predictive value for ventilatory support (VS) need. METHODS: Ambispective observational ethically approved study in COVID-19 pneumonia inpatients, validated in a second outpatient sample. Brixia score (BS) was applied to the first and second chest radiography required for suspected COVID-19 pneumonia to determine the predictive capacity of BS worsening for VS need. Intraclass correlation coefficient (ICC) was previously analyzed among three radiologists. Sensitivity, specificity, likelihood ratios, AUC, and odds ratio were calculated using ROC curves and binary logistic regression analysis. A value of p < .05 was considered statistically significant. RESULTS: A total of 120 inpatients (55 ± 14 years, 68 men) and 112 outpatients (56 ± 13 years, 61 men) were recruited. The average ICC of the BS was between 0.812 (95% confidence interval 0.745-0.878) and 0.906 (95% confidence interval 0.844-0.940). According to the multivariate analysis, a BS worsening per day > 1.3 points within 10 days of the onset of symptoms doubles the risk for requiring VS in inpatients and 5 times in outpatients (p < .001). The findings from the second chest radiography were always better predictors of VS requirement than those from the first one. CONCLUSION: The early radiological worsening of SARS-CoV-2 pneumonia after symptoms onset is a determining factor of the final prognosis. In elderly patients with some comorbidity and pneumonia, a 48-72-h follow-up radiograph is recommended. KEY POINTS: • An early worsening on chest X-ray in patients with SARS-CoV-2 pneumonia is highly predictive of the need for ventilatory support. • This radiological worsening rate can be easily assessed by comparing the first and the second chest X-ray. • In elderly patients with some comorbidity and SARS-CoV-2 pneumonia, close early radiological follow-up is recommended.


Assuntos
COVID-19 , SARS-CoV-2 , Idoso , Comorbidade , Feminino , Humanos , Masculino , Prognóstico , Radiografia
20.
Bioorg Med Chem ; 71: 116952, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35930852

RESUMO

The search for new drug candidates against Alzheimer's disease (AD) remains a complex challenge for medicinal chemists due to its multifactorial pathogenesis and incompletely understood physiopathology. In this context, we have explored the molecular hybridization of pharmacophore structural fragments from known bioactive molecules, aiming to obtain a novel molecular architecture in new chemical entities capable of concomitantly interacting with multiple targets in a so-called multi-target directed ligands (MTDLs) approach. This work describes the synthesis of 4-hydroxymethyl)piperidine-N-benzyl-acyl-hydrazone derivatives 5a-l, designed as novel MTDLs, showing improved multifunctional properties compared to the previously reported parent series of N-benzyl-(3-hydroxy)piperidine-acyl-hydrazone derivatives 4. The new improved derivatives were studied in silico, regarding their mode of interaction with AChE enzyme, and in vitro, for evaluation of their effects on the selective inhibition of cholinesterases, cellular antioxidant, and neuroprotective activities as their cytotoxicity in human neuroblastoma (SH-SY5Y) cells. Overall, compound PQM-181 (5 k) showed the best balanced selective and non-competitive inhibition of AChE (IC50 = 5.9 µM, SI > 5.1), with an additional antioxidant activity (IC50 = 7.45 µM) against neuronal t-BOOH-induced oxidative stress and neuroprotective ability against neurotoxicity elicited by both t-BOOH and OAß1-42, and a moderate ability to interfere in Aß1-42 aggregates, with low cytotoxicity and good predictive druggability properties, suggesting a multifunctional pharmacological profile suitable for further drug development against AD.


Assuntos
Doença de Alzheimer , Neuroblastoma , Fármacos Neuroprotetores , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Antioxidantes/farmacologia , Inibidores da Colinesterase/química , Desenho de Fármacos , Humanos , Hidrazonas/farmacologia , Hidrazonas/uso terapêutico , Ligantes , Estrutura Molecular , Neuroblastoma/tratamento farmacológico , Fármacos Neuroprotetores/química , Piperidinas/química , Relação Estrutura-Atividade
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