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1.
J Cell Sci ; 135(9)2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35319067

RESUMO

Stress response pathways protect the lung from the damaging effects of environmental toxicants. Here we investigate the role of the fragile X mental retardation protein (FMRP), a multifunctional protein implicated in stress responses, in the lung. We report that FMRP is expressed in murine and human lungs, in the airways and more broadly. Analysis of airway stress responses in mice and in a murine cell line ex vivo, using the well-established naphthalene injury model, reveals that FMRP-deficient cells exhibit increased expression of markers of oxidative and genotoxic stress and increased cell death. Further inquiry shows that FMRP-deficient cells fail to actuate the integrated stress response pathway (ISR) and upregulate the transcription factor ATF4. Knockdown of ATF4 expression phenocopies the loss of FMRP. We extend our analysis of the role of FMRP to human bronchial BEAS-2B cells, using a 9,10-phenanthrenequinone air pollutant model, to find that FMRP-deficient BEAS-2B cells also fail to actuate the ISR and exhibit greater susceptibility. Taken together, our data suggest that FMRP has a conserved role in protecting the airways by facilitating the ISR. This article has an associated First Person interview with the first author of the paper.


Assuntos
Proteína do X Frágil da Deficiência Intelectual , Xenobióticos , Animais , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Regulação da Expressão Gênica , Humanos , Pulmão/metabolismo , Camundongos , Fatores de Transcrição/metabolismo
2.
Toxicol Appl Pharmacol ; 485: 116904, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38503349

RESUMO

Manganese (Mn)-induced pulmonary toxicity and the underlying molecular mechanisms remain largely enigmatic. Further, in recent years, microRNAs (miRNAs) have emerged as regulators of several pollutants-mediated toxicity. In this context, our study aimed at elucidating whether miRNAs are involved in manganese (II) chloride (MnCl2) (Mn2+)-induced cytotoxicity in lung epithelial cells. Growth inhibition of Mn2+ towards normal human bronchial epithelial (BEAS-2B) and adenocarcinomic human alveolar basal epithelial (A549) cells was analyzed by MTT assay following 24 or 48 h treatment. Reactive oxygen species (ROS) generation, mitochondrial membrane potential (ΔΨm), cell cycle arrest, and apoptosis were evaluated by flow cytometry. RT-qPCR and Western blot were performed to analyze the expression of cyclins, anti-oxidant genes, and miRNAs. We used small RNA sequencing to investigate Mn2+-induced changes in miRNA expression patterns. In both cell lines, Mn2+ treatment inhibited growth in a dose-dependent manner. Further, compared with vehicle-treated cells, Mn2+ (250 µM) treatment induced ROS generation, cell cycle arrest, apoptosis, and decreased ΔΨm as well as altered the expression of cyclins and anti-oxidant genes. Sequencing data revealed that totally 296 miRNAs were differentially expressed in Mn2+-treated cells. Among them, miR-221-3p was one of the topmost down-regulated miRNAs in Mn2+-treated cells. We further confirmed this association in A549 cells. In addition, transient transfection was performed to study gain-of-function experiments. Forced expression of miR-221-3p significantly improved cell viability and reduced Mn2+-induced cell cycle arrest and apoptosis in BEAS-2B cells. In conclusion, miR-221-3p may be the most likely target that accounts for the cytotoxicity of Mn2+-exposed lung epithelial cells.


Assuntos
Apoptose , Células Epiteliais , Pulmão , MicroRNAs , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Células A549 , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Apoptose/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Compostos de Manganês , Manganês/toxicidade , Linhagem Celular , Cloretos/toxicidade , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga
3.
Molecules ; 26(22)2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34833955

RESUMO

NAD(P)H:quinone acceptor oxidoreductase-1 (NQO1) is a ubiquitous flavin adenine dinucleotide-dependent flavoprotein that promotes obligatory two-electron reductions of quinones, quinonimines, nitroaromatics, and azo dyes. NQO1 is a multifunctional antioxidant enzyme whose expression and deletion are linked to reduced and increased oxidative stress susceptibilities. NQO1 acts as both a tumor suppressor and tumor promoter; thus, the inhibition of NQO1 results in less tumor burden. In addition, the high expression of NQO1 is associated with a shorter survival time of cancer patients. Inhibiting NQO1 also enables certain anticancer agents to evade the detoxification process. In this study, a series of phytobioactives were screened based on their chemical classes such as coumarins, flavonoids, and triterpenoids for their action on NQO1. The in silico evaluations were conducted using PyRx virtual screening tools, where the flavone compound, Orientin showed a better binding affinity score of -8.18 when compared with standard inhibitor Dicumarol with favorable ADME properties. An MD simulation study found that the Orientin binding to NQO1 away from the substrate-binding site induces a potential conformational change in the substrate-binding site, thereby inhibiting substrate accessibility towards the FAD-binding domain. Furthermore, with this computational approach we are offering a scope for validation of the new therapeutic components for their in vitro and in vivo efficacy against NQO1.


Assuntos
Antineoplásicos/farmacologia , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/farmacologia , Antioxidantes/farmacologia , Sítios de Ligação/efeitos dos fármacos , Cumarínicos/farmacologia , Flavonas/farmacologia , Flavonoides/farmacologia , Humanos , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Triterpenos/farmacologia
4.
Inflammopharmacology ; 28(5): 1301-1314, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32372165

RESUMO

Pulmonary fibrosis (PF) is a chronic and irreversible scarring disease in the lung with limited treatment options. Therefore, it is critical to identify new therapeutic options. This study was undertaken to identify the effects of tannic acid (TA), a naturally occurring dietary polyphenol, in a mouse model of PF. Bleomycin (BLM) was intratracheally administered to induce PF. Administration of TA significantly reduced BLM-induced histological alterations, inflammatory cell infiltration and the levels of various inflammatory mediators (nitric oxide, leukotriene B4 and cytokines). Additionally, treatment with TA also impaired BLM-mediated increases in pro-fibrotic (transforming growth factor-ß1) and fibrotic markers (alpha-smooth muscle actin, vimentin, collagen 1 alpha and fibronectin) expression. Further investigation indicated that BLM-induced phosphorylation of Erk1/2 (extracellular signal-regulated kinases 1 and 2) in lungs was suppressed by TA treatment. Findings of this study suggest that TA has the potential to mitigate PF through inhibiting the inflammatory response and fibrotic process in lungs and that TA might be useful for the treatment of PF in clinical practice.


Assuntos
Anti-Inflamatórios/farmacologia , Fibrose Pulmonar/tratamento farmacológico , Taninos/farmacologia , Animais , Bleomicina , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fibrose Pulmonar/patologia
5.
J Cell Physiol ; 234(5): 6463-6476, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30246289

RESUMO

Acute lung injury (ALI) and its severe form acute respiratory distress syndrome (ARDS) remain a major cause of morbidity and mortality in critically ill patients, and no specific therapies are still available to control the mortality rate. Thus, we explored the preventive and therapeutic effects of tannic acid (TA), a natural polyphenol in the context of ALI. We used in vivo and in vitro models, respectively, using lipopolysaccharide (LPS) to induce ALI in mice and exposing J774 and BEAS-2B cells to LPS. In both preventive and therapeutic approaches, TA attenuated LPS-induced histopathological alterations, lipid peroxidation, lung permeability, infiltration of inflammatory cells, and the expression of proinflammatory mediators. In addition, in-vitro study showed that TA treatment could reduce the expression of proinflammatory mediators. Further studies revealed that TA-dampened inflammatory responses by downregulating the LPS-induced toll-like receptor 4 (TLR4) expression and inhibiting extracellular-signal-regulated kinase (ERK)1/2 and p38 mitogen-activated protein kinase (MAPK) activation. Furthermore, cells treated with the inhibitors of ERK1/2 (PD98059) and p38 (SB203580) mitigated the expression of cytokines induced by LPS, thus suggesting that ERK1/2 and p38 activity are required for the inflammatory response. In conclusion, TA could attenuate LPS-induced inflammation and may be a potential therapeutic agent for ALI-associated inflammation in clinical settings.


Assuntos
Lesão Pulmonar Aguda/patologia , Proteínas Quinases Ativadas por Mitógeno/biossíntese , Taninos/farmacologia , Receptor 4 Toll-Like/biossíntese , Lesão Pulmonar Aguda/metabolismo , Animais , Modelos Animais de Doenças , Regulação para Baixo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos
6.
Respir Res ; 20(1): 190, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31429757

RESUMO

BACKGROUND: Patients with chronic obstructive pulmonary disease (COPD) have high oxidative stress associated with the severity of the disease. Nuclear factor erythroid-2 related factor 2 (Nrf2)-directed stress response plays a critical role in the protection of lung cells to oxidative stress by upregulating antioxidant genes in response to tobacco smoke. There is a critical gap in our knowledge about Nrf-2 regulated genes in active smokers and former-smokers with COPD in different cell types from of lungs and surrogate peripheral tissues. METHODS: We compared the expression of Nrf2 and six of its target genes in alveolar macrophages, nasal, and bronchial epithelium and peripheral blood mononuclear cells (PBMCs) in current and former smokers with COPD. We compared cell-type specific of Nrf2 and its target genes as well as markers of oxidative and inflammatory stress. RESULTS: We enrolled 89 patients; expression all Nrf2 target gene measured were significantly higher in the bronchial epithelium from smokers compared to non-smokers. None were elevated in alveolar macrophages and only one was elevated in each of the other compartments. CONCLUSION: Bronchial epithelium is the most responsive tissue for transcriptional activation of Nrf2 target genes in active smokers compared to former-smokers with COPD that correlated with oxidative stress and inflammatory markers. There were no consistent trends in gene expression in other cell types tested. TRIAL REGISTRATION: Clinicaltrials.gov : NCT01335971.


Assuntos
Antioxidantes/metabolismo , Expressão Gênica , Inflamação/genética , Inflamação/metabolismo , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fumar/genética , Fumar/metabolismo , Idoso , Brônquios/metabolismo , Método Duplo-Cego , Epitélio/metabolismo , Feminino , Humanos , Isotiocianatos/uso terapêutico , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Fator 2 Relacionado a NF-E2/biossíntese , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/genética , Abandono do Hábito de Fumar , Sulfóxidos , Ativação Transcricional
7.
Proc Natl Acad Sci U S A ; 112(50): E6927-36, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26621751

RESUMO

Delayed revascularization of ischemic neural tissue is a major impediment to preservation of function in central nervous system (CNS) diseases including stroke and ischemic retinopathies. Therapeutic strategies allowing rapid revascularization are greatly needed to reduce ischemia-induced cellular damage and suppress harmful pathologic neovascularization. However, key mechanisms governing vascular recovery in ischemic CNS, including regulatory molecules governing the transition from tissue injury to tissue repair, are largely unknown. NF-E2-related factor 2 (Nrf2) is a major stress-response transcription factor well known for its cell-intrinsic cytoprotective function. However, its role in cell-cell crosstalk is less appreciated. Here we report that Nrf2 is highly activated in ischemic retina and promotes revascularization by modulating neurons in their paracrine regulation of endothelial cells. Global Nrf2 deficiency strongly suppresses retinal revascularization and increases pathologic neovascularization in a mouse model of ischemic retinopathy. Conditional knockout studies demonstrate a major role for neuronal Nrf2 in vascular regrowth into avascular retina. Deletion of neuronal Nrf2 results in semaphorin 6A (Sema6A) induction in hypoxic/ischemic retinal ganglion cells in a hypoxia-inducible factor-1 alpha (HIF-1α)-dependent fashion. Sema6A expression increases in avascular inner retina and colocalizes with Nrf2 in human fetal eyes. Extracellular Sema6A leads to dose-dependent suppression of the migratory phenotype of endothelial cells through activation of Notch signaling. Lentiviral-mediated delivery of Sema6A small hairpin RNA (shRNA) abrogates the defective retinal revascularization in Nrf2-deficient mice. Importantly, pharmacologic Nrf2 activation promotes reparative angiogenesis and suppresses pathologic neovascularization. Our findings reveal a unique function of Nrf2 in reprogramming ischemic tissue toward neurovascular repair via Sema6A regulation, providing a potential therapeutic strategy for ischemic retinal and CNS diseases.


Assuntos
Isquemia/metabolismo , Fator 2 Relacionado a NF-E2/fisiologia , Neurônios/metabolismo , Vasos Retinianos/crescimento & desenvolvimento , Semaforinas/metabolismo , Animais , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Isquemia/patologia , Camundongos , Neovascularização Patológica , Receptores Notch/metabolismo , Regeneração , Vasos Retinianos/patologia , Transdução de Sinais
8.
Am J Physiol Lung Cell Mol Physiol ; 313(1): L138-L153, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28408365

RESUMO

Downregulation of the alveolar macrophage (AM) receptor with collagenous structure (MARCO) leads to susceptibility to postinfluenza bacterial pneumonia, a major cause of morbidity and mortality. We sought to determine whether immunomodulation of MARCO could improve host defense and resistance to secondary bacterial pneumonia. RNAseq analysis identified a striking increase in MARCO expression between days 9 and 11 after influenza infection and indicated important roles for Akt and Nrf2 in MARCO recovery. In vitro, primary human AM-like monocyte-derived macrophages (AM-MDMs) and THP-1 macrophages were treated with IFNγ to model influenza effects. Activators of Nrf2 (sulforaphane) or Akt (SC79) caused increased MARCO expression and a MARCO-dependent improvement in phagocytosis in IFNγ-treated cells and improved survival in mice with postinfluenza pneumococcal pneumonia. Transcription factor analysis also indicated a role for transcription factor E-box (TFEB) in MARCO recovery. Overexpression of TFEB in THP-1 cells led to marked increases in MARCO. The ability of Akt activation to increase MARCO expression in IFNγ-treated AM-MDMs was abrogated in TFEB-knockdown cells, indicating Akt increases MARCO expression through TFEB. Increasing MARCO expression by targeting Nrf2 signaling or the Akt-TFEB-MARCO pathway are promising strategies to improve bacterial clearance and survival in postinfluenza bacterial pneumonia.


Assuntos
Resistência à Doença , Fatores Imunológicos/farmacologia , Influenza Humana/complicações , Pneumonia Bacteriana/etiologia , Pneumonia Bacteriana/imunologia , Receptores Imunológicos/metabolismo , Animais , Sequência de Bases , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Líquido da Lavagem Broncoalveolar , Catequina/análogos & derivados , Catequina/farmacologia , Linhagem Celular , Citocinas/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Humanos , Interferon gama/farmacologia , Isotiocianatos/farmacologia , MAP Quinase Quinase Quinases/metabolismo , Macrófagos Alveolares/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Infecções por Orthomyxoviridae/complicações , Fagocitose/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Imunológicos/genética , Análise de Sequência de RNA , Transdução de Sinais , Staphylococcus aureus/efeitos dos fármacos , Sulfóxidos , Regulação para Cima/genética
9.
J Cell Physiol ; 231(10): 2097-106, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26790856

RESUMO

The acute respiratory distress syndrome (ARDS), a severe form of acute lung injury (ALI), is a very common condition associated with critically ill patients, which causes substantial morbidity and mortality worldwide. Despite decades of research, effective therapeutic strategies for clinical ALI/ARDS are not available. In recent years, microRNAs (miRNAs), small non-coding molecules have emerged as a major area of biomedical research as they post-transcriptionally regulate gene expression in diverse biological and pathological processes, including ALI/ARDS. In this context, this present review summarizes a large body of evidence implicating miRNAs and their target molecules in ALI/ARDS originating largely from studies using animal and cell culture model systems of ALI/ARDS. We have also focused on the involvement of miRNAs in macrophage polarization, which play a critical role in regulating the pathogenesis of ALI/ARDS. Finally, the possible future directions that might lead to novel therapeutic strategies for the treatment of ALI/ARDS are also reviewed. J. Cell. Physiol. 231: 2097-2106, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Lesão Pulmonar Aguda/genética , Expressão Gênica/genética , MicroRNAs/genética , Processamento de Proteína Pós-Traducional/genética , Síndrome do Desconforto Respiratório/genética , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/terapia , Animais , Modelos Animais de Doenças , Humanos , Síndrome do Desconforto Respiratório/terapia
10.
Proc Natl Acad Sci U S A ; 110(41): E3910-8, 2013 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-24062466

RESUMO

Angiogenesis, in which new blood vessels form via endothelial cell (EC) sprouting from existing vessels, is a critical event in embryonic development and multiple disease processes. Many insights have been made into key EC receptors and ligands/growth factors that govern sprouting angiogenesis, but intracellular molecular mechanisms of this process are not well understood. NF-E2-related factor 2 (Nrf2) is a transcription factor well-known for regulating the stress response in multiple pathologic settings, but its role in development is less appreciated. Here, we show that Nrf2 is increased and activated during vascular development. Global deletion of Nrf2 resulted in reduction of vascular density as well as EC sprouting. This was also observed with specific deletion of Nrf2 in ECs, but not with deletion of Nrf2 in the surrounding nonvascular tissue. Nrf2 deletion resulted in increased delta-like ligand 4 (Dll4) expression and Notch activity in ECs. Blockade of Dll4 or Notch signaling restored the vascular phenotype in Nrf2 KOs. Constitutive activation of endothelial Nrf2 enhanced EC sprouting and vascularization by suppression of Dll4/Notch signaling in vivo and in vitro. Nrf2 activation in ECs suppressed Dll4 expression under normoxia and hypoxia and inhibited Dll4-induced Notch signaling. Activation of Nrf2 blocked VEGF induction of VEGFR2-PI3K/Akt and downregulated HIF-2α in ECs, which may serve as important mechanisms for Nrf2 inhibition of Dll4 and Notch signaling. Our data reveal a function for Nrf2 in promoting the angiogenic sprouting phenotype in vascular ECs.


Assuntos
Células Endoteliais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Fator 2 Relacionado a NF-E2/metabolismo , Neovascularização Fisiológica/fisiologia , Vasos Retinianos/embriologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Western Blotting , Bromodesoxiuridina , Proteínas de Ligação ao Cálcio , Crioultramicrotomia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Microdissecção e Captura a Laser , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/genética , Fosfatidilinositol 3-Quinases/metabolismo , Receptores Notch/metabolismo , Retina/citologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
J Neurochem ; 133(2): 233-41, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25683606

RESUMO

Retinal ischemia plays a critical role in multiple vision-threatening diseases and leads to death of retinal neurons, particularly ganglion cells. Oxidative stress plays an important role in this ganglion cell loss. Nrf2 (NF-E2-related factor 2) is a major regulator of the antioxidant response, and its role in the retina is increasingly appreciated. We investigated the potential retinal neuroprotective function of Nrf2 after ischemia-reperfusion (I/R) injury. In an experimental model of retinal I/R, Nrf2 knockout mice exhibited much greater loss of neuronal cells in the ganglion cell layer than wild-type mice. Primary retinal ganglion cells isolated from Nrf2 knockout mice exhibited decreased cell viability compared to wild-type retinal ganglion cells, demonstrating the cell-intrinsic protective role of Nrf2. The retinal neuronal cell line 661W exhibited reduced cell viability following siRNA-mediated knockdown of Nrf2 under conditions of oxidative stress, and this was associated with exacerbation of increase in reactive oxygen species. The synthetic triterpenoid CDDO-Im (2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide), a potent Nrf2 activator, inhibited reactive oxygen species increase in cultured 661W under oxidative stress conditions and increased neuronal cell survival after I/R injury in wild-type, but not Nrf2 knockout mice. Our findings indicate that Nrf2 exhibits a retinal neuroprotective function in I/R and suggest that pharmacologic activation of Nrf2 could be a therapeutic strategy. Oxidative stress is thought to be an important mediator of retinal ganglion cell death in ischemia-reperfusion injury. We found that the transcription factor NF-E2-related factor 2 (Nrf2), a major regulator of oxidative stress, is an important endogenous neuroprotective molecule in retinal ganglion cells in ischemia-reperfusion, exerting a cell-autonomous protective effect.  The triterpenoid 2-Cyano-3,12-dioxooleana-1,9-dien-28-imidazolide (CDDO-Im) reduces neurodegeneration following ischemia-reperfusion in an Nrf2-dependent fashion. This suggests that Nrf2-activating drugs including triterpenoids could be a therapeutic strategy for retinal neuroprotection.


Assuntos
Isquemia/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Sobrevivência Celular/genética , Células Cultivadas , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Imidazóis/farmacologia , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fator 2 Relacionado a NF-E2/genética , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/farmacologia , RNA Interferente Pequeno/farmacologia , Retina/citologia , Células Ganglionares da Retina/metabolismo , terc-Butil Hidroperóxido/farmacologia
12.
Diabetologia ; 57(1): 204-13, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24186494

RESUMO

AIMS/HYPOTHESIS: Although much is known about the pathophysiological processes contributing to diabetic retinopathy (DR), the role of protective pathways has received less attention. The transcription factor nuclear factor erythroid-2-related factor 2 (also known as NFE2L2 or NRF2) is an important regulator of oxidative stress and also has anti-inflammatory effects. The objective of this study was to explore the potential role of NRF2 as a protective mechanism in DR. METHODS: Retinal expression of NRF2 was investigated in human donor and mouse eyes by immunohistochemistry. The effect of NRF2 modulation on oxidative stress was studied in the human Müller cell line MIO-M1. Non-diabetic and streptozotocin-induced diabetic wild-type and Nrf2 knockout mice were evaluated for multiple DR endpoints. RESULTS: NRF2 was expressed prominently in Müller glial cells and astrocytes in both human and mouse retinas. In cultured MIO-M1 cells, NRF2 inhibition significantly decreased antioxidant gene expression and exacerbated tert-butyl hydroperoxide- and hydrogen peroxide-induced oxidative stress. NRF2 activation strongly increased NRF2 target gene expression and suppressed oxidant-induced reactive oxygen species. Diabetic mice exhibited retinal NRF2 activation, indicated by nuclear translocation. Superoxide levels were significantly increased by diabetes in Nrf2 knockout mice as compared with wild-type mice. Diabetic Nrf2 knockout mice exhibited a reduction in retinal glutathione and an increase in TNF-α protein compared with wild-type mice. Nrf2 knockout mice exhibited early onset of blood-retina barrier dysfunction and exacerbation of neuronal dysfunction in diabetes. CONCLUSIONS/INTERPRETATION: These results indicate that NRF2 is an important protective factor regulating the progression of DR and suggest enhancement of the NRF2 pathway as a potential therapeutic strategy.


Assuntos
Retinopatia Diabética/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Linhagem Celular , Retinopatia Diabética/genética , Humanos , Masculino , Camundongos , Camundongos Mutantes , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo/genética , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Retina/metabolismo , Retina/patologia
13.
J Biochem ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38960390

RESUMO

Erythrocytes are important vascular components that play vital roles in maintaining vascular homeostasis, in addition to carrying oxygen. Previously, we reported that the changes in the internal milieu (e.g., hyperglycemia or hypercholesterolemia) increase erythrocyte adhesion to various ECM components, potentially through altering glycosaminoglycans (GAGs). In this study, we have investigated the expression of syndecan (Sdc) family members that could be involved in mediating cytoadherence under conditions of dyslipidemia and hyperglycemia. Among the Sdc family members analyzed, we found significant overexpression of Sdc-3 in erythrocyte membranes harvested from high-fat-fed control and diabetic animals. Animal studies revealed a positive correlation between Sdc-3 expression, blood sugar levels, and erythrocyte adhesion. In the human study, diabetic cohorts with BMI >24.9 showed significantly increased expression of Sdc-3. Interestingly, blocking the Sdc-3 moiety with an anti-Sdc-3 antibody revealed that the core protein might not be directly involved in erythrocyte adhesion to fibronectin despite the GAGs bringing about adhesion. Lastly, Nano LC-MS/MS verified the presence of Sdc-3 in erythrocyte membranes. In conclusion, the high-fat diet and diabetes modulated Sdc-3 expression in the erythrocyte membrane, which may alter its adhesive properties and promote vascular complications.

14.
Emerg Microbes Infect ; 12(1): 2211685, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37161660

RESUMO

Patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza A virus (FLUAV) coinfections were associated with severe respiratory failure and more deaths. Here, we developed a model for studying SARS-CoV-2 and FLUAV coinfection using human pluripotent stem cell-induced alveolar type II organoids (hiAT2). hiAT2 organoids were susceptible to infection by both viruses and had features of severe lung damage. A single virus markedly enhanced the susceptibility to other virus infections. SARS-CoV-2 delta variants upregulated α-2-3-linked sialic acid, while FLUAV upregulated angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2). Moreover, coinfection by SARS-CoV-2 and FLUAV caused hyperactivation of proinflammatory and immune-related signaling pathways and cellular damage compared to a respective single virus in hiAT2 organoids. This study provides insight into molecular mechanisms underlying enhanced infectivity and severity in patients with co-infection of SARS-CoV-2 and FLUAV, which may aid in the development of therapeutics for such co-infection cases.


Assuntos
COVID-19 , Coinfecção , Influenza Humana , Células-Tronco Pluripotentes , Humanos , SARS-CoV-2 , Influenza Humana/metabolismo , Pulmão , Replicação Viral , Organoides
15.
Indian Heart J ; 75(5): 343-346, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37217095

RESUMO

BACKGROUND: It is essential to investigate the prevalence of CYP2C19 alleles that affect drug metabolism. This study measures the allelic and genotypic frequencies of CYP2C19 loss-of-function (LoF) alleles CYP2C19∗2, CYP2C19∗3, and gain-of-function (GoF) alleles CYP2C19∗17 in the general population. METHODOLOGY: The study involved 300 healthy subjects between the ages of 18 and 85 recruited by simple random sampling. Allele-specific touchdown PCR was employed to identify the various alleles. The genotype and allele frequencies were calculated and checked for Hardy-Weinberg equilibrium. The phenotypic prediction of ultra-rapid metabolizer (UM = ∗17/∗17), extensive metabolizer (EM = ∗1/∗17, ∗1/∗1), intermediate metabolizer (IM = ∗1/∗2, ∗1/∗3, ∗2/∗17) and poor metabolizer (PM = ∗2/∗2, ∗2/∗3, ∗3/∗3) was made based on their genotype. RESULTS: The allele frequency of CYP2C19∗2, CYP2C19∗3, and CYP2C19∗17 was 0.365, 0.0033, and 0.18, respectively. The IM phenotype predominated with an overall frequency of 46.67%, including 101 subjects with ∗1/∗2, two subjects with ∗1/∗3, and 37 subjects with ∗2/∗17 genotype. This was followed by EM phenotype with an overall frequency of 35%, including 35 subjects with ∗1/∗17 and 70 subjects with ∗1/∗1 genotype. PM phenotype had an overall frequency of 12.67%, including 38 subjects with ∗2/∗2 genotype, and UM phenotype had an overall frequency of 5.67%, including 17 subjects with ∗17/∗17 genotype. CONCLUSION: Given the high allelic frequency of PM in the study population, a pre-treatment test to identify the individual's genotype may be recommended to decide the dosage, monitor the drug response, and avoid adverse drug reactions.


Assuntos
Hidrocarboneto de Aril Hidroxilases , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Clopidogrel , Hidrocarboneto de Aril Hidroxilases/genética , Citocromo P-450 CYP2C19/genética , Frequência do Gene , Genótipo , Alelos , Inibidores da Agregação Plaquetária/uso terapêutico
16.
Free Radic Biol Med ; 205: 234-243, 2023 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-37328018

RESUMO

PURPOSE: To investigate the role of NRF2 signalling in conferring superior prognosis in patients with HPV positive (HPV+ve) head & neck squamous cell carcinomas (HNSCC) compared to HPV negative (HPV-ve) HNSCC and develop molecular markers for selection of HPV+ve HNSCC patients for treatment de-escalation trials. METHODS: NRF2 activity (NRF2, KEAP1, and NRF2-transcriptional targets), p16, and p53 levels between HPV+ve HNSCC and HPV-ve HNSCC in prospective and retrospective tumor samples as well as from TCGA database were compared. Cancer cells were transfected with HPV-E6/E7 plasmid to elucidate if HPV infection represses NRF2 activity and sensitizes to chemo-radiotherapy. RESULTS: Prospective analysis revealed a marked reduction in expression of NRF2, and its downstream genes in HPV+ve tumors compared to HPV-ve tumors. A retrospective analysis by IHC revealed significantly lower NQO1 in p16high tumors compared to p16low tumors and the NQO1 expression correlated negatively with p16 and positively with p53. Analysis of the TCGA database confirmed low constitutive NRF2 activity in HPV+ve HNSCC compared to HPV-ve HNSCC and revealed that HPV+ve HNSCC patients with 'low NQO1' expression showed better overall survival compared to HPV+ve HNSCC patients with 'high NQO1' expression. Ectopic expression of HPV-E6/E7 plasmid in various cancer cells repressed constitutive NRF2 activity, reduced total GSH, increased ROS levels, and sensitized the cancer cells to cisplatin and ionizing radiation. CONCLUSION: Low constitutive NRF2 activity contributes to better prognosis of HPV+ve HNSCC patients. Co-expression of p16high, NQO1low, and p53low could serve as a predictive biomarker for the selection of HPV + ve HNSCC patients for de-escalation trials.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Papillomavirus Humano , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/metabolismo , Carcinoma de Células Escamosas/metabolismo , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo
17.
Indian J Psychiatry ; 65(11): 1143-1150, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38249149

RESUMO

Background: The coronavirus disease 2019 (COVID-19) pandemic has taken a toll on the well-being and quality of life (QoL) of healthcare professionals, especially nurses. Insomnia, a common consequence of the pandemic, adds to the physical and mental strain on healthcare workers. Aim: This study aimed to assess the impact of workplace yoga intervention on insomnia severity and QoL among female nursing and healthcare professionals during the pandemic. Methods: A pre-post-interventional study was conducted among 173 nursing professionals working in a hospital setting. Baseline assessments collected age, body mass index (BMI), insomnia severity using the Insomnia Severity Index (ISI), and QoL using the World Health Organization Quality-of-Life Brief Version (WHOQOL-BREF). A 6-week workplace yoga intervention was conducted by trained professionals, followed by posttest assessments. Results: Among 173 participants, 57 had insomnia. Participants without significant insomnia had higher QoL scores (P < 0.001). Following the yoga intervention, both subthreshold and moderate clinical insomnia groups experienced reduced insomnia severity (P < 0.001). Quality-of-life scores in the physical, psychological, and environmental domains improved significantly (P < 0.05). Conclusion: Workplace yoga intervention appears to be a promising approach to alleviate insomnia and enhance QoL among female nursing and healthcare professionals during the COVID-19 pandemic. Implementing tailored workplace yoga programs can play a crucial role in promoting the well-being and resilience of healthcare workers, contributing to a positive work environment and improved patient care outcomes.

18.
Food Funct ; 14(10): 4734-4751, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37114361

RESUMO

Pharmacological activation of nuclear factor erythroid 2 related factor 2 (NRF2) provides protection against several environmental diseases by inhibiting oxidative and inflammatory injury. Besides high in protein and minerals, Moringa oleifera leaves contain several bioactive compounds, predominantly isothiocyanate moringin and polyphenols, which are potent inducers of NRF2. Hence, M. oleifera leaves represent a valuable food source that could be developed as a functional food for targeting NRF2 signaling. In the current study, we have developed a palatable M. oleifera leaf preparation (henceforth referred as ME-D) that showed reproducibly a high potential to activate NRF2. Treatment of BEAS-2B cells with ME-D significantly increased NRF2-regulated antioxidant genes (NQO1, HMOX1) and total GSH levels. In the presence of brusatol (a NRF2 inhibitor), ME-D-induced increase in NQO1 expression was significantly diminished. Pre-treatment of cells with ME-D mitigated reactive oxygen species, lipid peroxidation and cytotoxicity induced by pro-oxidants. Furthermore, ME-D pre-treatment markedly inhibited nitric oxide production, secretory IL-6 and TNF-α levels, and transcriptional expression of Nos2, Il-6, and Tnf-α in macrophages exposed to lipopolysaccharide. Biochemical profiling by LC-HRMS revealed glucomoringin, moringin, and several polyphenols in ME-D. Oral administration of ME-D significantly increased NRF2-regulated antioxidant genes in the small intestine, liver, and lungs. Lastly, prophylactic administration of ME-D significantly mitigated lung inflammation in mice exposed to particulate matter for 3-days or 3-months. In conclusion, we have developed a pharmacologically active standardized palatable preparation of M. oleifera leaves as a functional food to activate NRF2 signaling, which can be consumed as a beverage (hot soup) or freeze-dried powder for reducing the risk from environmental respiratory disease.


Assuntos
Antioxidantes , Moringa oleifera , Camundongos , Animais , Antioxidantes/farmacologia , Moringa oleifera/química , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Interleucina-6 , Alimento Funcional , Fator de Necrose Tumoral alfa , Anti-Inflamatórios/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Espécies Reativas de Oxigênio
19.
Biochem Biophys Res Commun ; 426(2): 253-9, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-22935414

RESUMO

Patients with COPD are associated with poor pulmonary anti-bacterial innate defenses, which increase the risk for frequent acute exacerbations caused by bacterial infection. Despite elevated numbers of phagocytes (macrophages and neutrophils), airways of patients with COPD show stable bacterial colonization. A defect in the phagocytic ability of alveolar macrophages (AMs) is one of the primary reasons for failure to clear the invading bacteria in airways of smokers and COPD patients and also in mice exposed to cigarette smoke (CS). Oxidative stress, as a result of CS exposure is implicated; however, the factors or mediators that inhibit phagocytic activity of AMs in lungs of smokers remain unclear. In the current study, we provide evidence that accumulation of oxidized phospholipids (Ox-PLs) mediate inhibition of phagocytic function of AMs in CS-exposed mice. Mice exposed to 6months of CS showed impaired bacterial phagocytosis and clearance by AMs and elevated levels of Ox-PLs in bronchoalveolar lavage fluid (BALF), compared to mice exposed to room air. Intratracheal instillation of oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (OX-PAPC) inhibited phagocytic activity of AMs and impaired pulmonary bacterial clearance in mice. In vitro studies demonstrated that exposure of J774 macrophages to OX-PAPC inhibited bacterial phagocytosis and clearance. However, pre-treatment of OX-PAPC with the monoclonal antibody EO6, which specifically binds to oxidized phospholipid but not native phospholipid, abolished OX-PAPC induced inhibition of bacterial phagocytosis and clearance. Incubation of BALF retrieved from CS-exposed mice impaired bacterial phagocytosis by J774 macrophages, which was abolished by pre-treatment of BALF with the EO6 antibody. In conclusion, our study shows that Ox-PLs generated following chronic CS exposure could play a crucial role in inhibiting phagocytic function of AMs and thus impair pulmonary anti-bacterial innate defenses in CS-exposed mice. Therapeutic approaches that augment pulmonary antioxidant defenses could be beneficial in reducing oxidative stress-driven impairment of phagocytosis by AMs in smokers and COPD patients.


Assuntos
Infecções Bacterianas/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Estresse Oxidativo/imunologia , Fosfolipídeos/imunologia , Fumaça , Fumar/imunologia , Animais , Anticorpos Monoclonais/imunologia , Líquido da Lavagem Broncoalveolar/imunologia , Exposição por Inalação , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Fagocitose/imunologia , Fosfatidilcolinas/imunologia , Fosfatidilcolinas/farmacologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/microbiologia
20.
J Carcinog ; 11: 8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22919281

RESUMO

BACKGROUND: Sulforaphane (SFN), an activator of nuclear factor erythroid-2 related factor 2 (Nrf2), is a promising chemopreventive agent which is undergoing clinical trial for several diseases. Studies have indicated that there is gain of Nrf2 function in lung cancer and other solid tumors because of mutations in the inhibitor Kelch-like ECH-associated protein 1 (Keap1). More recently, several oncogenes have been shown to activate Nrf2 signaling as the main prosurvival pathway mediating ROS detoxification, senescence evasion, and neoplastic transformation. Thus, it is important to determine if there is any risk of enhanced lung tumorigenesis associated with prolonged administration of SFN using mouse models of cancer. MATERIALS AND METHODS: We evaluated the effect of prolonged SFN treatment on oncogenic K-ras (K-ras(LSL-G12D))-driven lung tumorigenesis. One week post mutant-K-ras expression, mice were treated with SFN (0.5 mg, 5 d/wk) for 3 months by means of a nebulizer. Fourteen weeks after mutant K-ras expression (K-ras(LSL-G12D)), mice were sacrificed, and lung sections were screened for neoplastic foci. Expression of Nrf2-dependent genes was measured using real time RT-PCR. We also determined the effect of prolonged SFN treatment on the growth of preclinical xenograft models using human A549 (with mutant K-ras and Keap1 allele) and H1975 [with mutant epidermal growth factor receptor (EGFR) allele] nonsmall cell lung cancer cells. RESULTS: Systemic SFN administration did not promote the growth of K-ras(LSL-G12D)-induced lung tumors and had no significant effect on the growth of A549 and H1975 established tumor xenografts in nude mice. Interestingly, localized delivery of SFN significantly attenuated the growth of A549 tumors in nude mice, suggesting an Nrf2-independent antitumorigenic activity of SFN. CONCLUSIONS: Our results demonstrate that prolonged SFN treatment does not promote lung tumorigenesis in various mouse models of lung cancer.

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