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1.
Int J Mol Sci ; 22(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502052

RESUMO

The role of reactive oxygen species (ROS) in ABA-induced increase in hydraulic conductivity was hypothesized to be dependent on an increase in aquaporin water channel (AQP) abundance. Single ABA application or its combination with ROS manipulators (ROS scavenger ascorbic acid and NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI)) were studied on detached roots of barley plants. We measured the osmotically driven flow rate of xylem sap and calculated root hydraulic conductivity. In parallel, immunolocalization of ABA and HvPIP2;2 AQPs was performed with corresponding specific antibodies. ABA treatment increased the flow rate of xylem, root hydraulic conductivity and immunostaining for ABA and HvPIP2;2, while the addition of antioxidants prevented the effects of this hormone. The obtained results confirmed the involvement of ROS in ABA effect on hydraulic conductivity, in particular, the importance of H2O2 production by ABA-treated plants for the effect of this hormone on AQP abundance.


Assuntos
Ácido Abscísico/farmacologia , Aquaporinas/metabolismo , Osmose , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Inibidores Enzimáticos/farmacologia , Hordeum/efeitos dos fármacos , Hordeum/metabolismo , NADPH Oxidases/antagonistas & inibidores , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Raízes de Plantas/efeitos dos fármacos , Xilema/efeitos dos fármacos , Xilema/metabolismo
2.
Molecules ; 26(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34443598

RESUMO

Apocynin (APO) is a known multi-enzymatic complexed compound, employed as a viable NADPH oxidase (NOX) inhibitor, extensively used in both traditional and modern-day therapeutic strategies to combat neuronal disorders. However, its therapeutic efficacy is limited by lower solubility and lesser bioavailability; thus, a suitable nanocarrier system to overcome such limitations is needed. The present study is designed to fabricate APO-loaded polymeric nanoparticles (APO-NPs) to enhance its therapeutic efficacy and sustainability in the biological system. The optimized APO NPs in the study exhibited 103.6 ± 6.8 nm and -13.7 ± 0.43 mV of particle size and zeta potential, respectively, along with further confirmation by TEM. In addition, the antioxidant (AO) abilities quantified by DPPH and nitric oxide scavenging assays exhibited comparatively higher AO potential of APO-NPs than APO alone. An in-vitro release profile displayed a linear diffusion pattern of zero order kinetics for APO from the NPs, followed by its cytotoxicity evaluation on the PC12 cell line, which revealed minimal toxicity with higher cell viability, even after treatment with a stress inducer (H2O2). The stability of APO-NPs after six months showed minimal AO decline in comparison to APO only, indicating that the designed nano-formulation enhanced therapeutic efficacy for modulating NOX-mediated ROS generation.


Assuntos
Acetofenonas/química , Acetofenonas/farmacologia , Peróxido de Hidrogênio/farmacologia , NADPH Oxidases/metabolismo , Nanopartículas/química , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Células PC12 , Ratos
3.
Nutrients ; 13(8)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34444829

RESUMO

Our group tested the effects of Lactobacillus fermentum CECT5716 (LC40) and/or Bifidobacterium breve CECT7263 (BFM) in the prevention of gut dysbiosis, hypertension and endothelial dysfunction in a pharmacologically-induced model of systemic lupus erythematosus (SLE). We treated eight-week-old BALB/cByJRj mice without (Ctrl) or with the agonist of TLR-7 Imiquimod (IMQ) for 8 weeks. Concomitantly, LC40 (109 CFU/mL) and BFM (109 CFU/mL) were administered through oral gavage once a day. IMQ induced intestinal dysbiosis consisting of a decrease in the α-diversity measured with Chao-richness and numbers of species. LC40 and BFM did not restore these parameters. The three-dimensional principal component analysis of bacterial taxa in stool samples presented perfect clustering between Ctrl and IMQ groups. Clusters corresponding to LC40 and BFM were more akin to IMQ. BFM and LC40 were detected colonizing the gut microbiota of mice treated respectively. LC40 and BFM decreased plasma double-stranded DNA autoantibodies, and B cells in spleen, which were increased in the IMQ group. Also, LC40 and BFM treatments activated TLR9, reduced T cells activation, and Th17 polarization in mesenteric lymph nodes. Aortae from IMQ mice displayed a decreased endothelium-dependent vasodilator response to acetylcholine linked to pro-inflammatory and pro-oxidative status, which were normalized by both BFM and LC40. In conclusion, we demonstrate for the first time that the chronic treatment with LC40 or BFM prevented hypertension and endothelial dysfunction in a mouse lupus model induced by TLR-7 activation.


Assuntos
Hipertensão/prevenção & controle , Lúpus Eritematoso Sistêmico/complicações , Probióticos/uso terapêutico , Receptor 7 Toll-Like/agonistas , Animais , Bifidobacterium breve , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Disbiose/microbiologia , Feminino , Microbioma Gastrointestinal , Imunidade , Lactobacillus fermentum , Lúpus Eritematoso Sistêmico/imunologia , Glicoproteínas de Membrana , Camundongos , Camundongos Endogâmicos BALB C , NADPH Oxidases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , RNA Ribossômico 16S , Espécies Reativas de Oxigênio
4.
Molecules ; 26(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34299420

RESUMO

A comparative study of volatile constituents, antioxidant activity, and molecular docking was conducted between essential oils from Mentha longifolia L., Mentha spicata L., and Origanum majorana L., widely cultivated in Madinah. The investigation of volatile oils extracted by hydrodistillation was performed using Gas Chromatography-Mass Spectrometry (GC-MS). A total number of 29, 42, and 29 components were identified in M. longifolia, M. spicata, and O. majorana representing, respectively, 95.91, 94.62, and 98.42, of the total oils. Pulegone (38.42%), 1,8-cineole (15.60%), menthone (13.20%), and isopulegone (9.81%) were the dominant compounds in M. longifolia oil; carvone (35.14%), limonene (27.11%), germacrene D (4.73%), and ß-caryophyllene (3.02%) were dominant in M. spicata oil; terpin-4-ol (42.47%), trans-sabinene hydrate (8.52%), γ-terpinene (7.90%), α-terpineol (7.38%), linalool (6.35%), α-terpinene (5.42%), and cis-sabinene hydrate (3.14%) were dominant in O. majorana oil. The antioxidant activity, assessed using DPPH free radical-scavenging and ABTS assays, was found to be the highest in O. majorana volatile oil, followed by M. spicata and M. longifolia, which is consistent with the differences in total phenolic content and volatile constituents identified in investigated oils. In the same context, molecular docking of the main identified volatiles on NADPH oxidase showed a higher binding affinity for cis-verbenyl acetate, followed by ß-elemene and linalool, compared to the control (dextromethorphan). These results prove significant antioxidant abilities of the investigated oils, which may be considered for further analyses concerning the control of oxidative stress, as well as for their use as possible antioxidant agents in the pharmaceutical industry.


Assuntos
Antioxidantes/farmacologia , Mentha/química , NADPH Oxidases/metabolismo , Óleos Voláteis/farmacologia , Origanum/química , Compostos Orgânicos Voláteis/farmacologia , Antioxidantes/análise , Simulação de Acoplamento Molecular , Óleos Voláteis/análise , Arábia Saudita , Compostos Orgânicos Voláteis/análise
5.
Nat Microbiol ; 6(7): 852-864, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34194036

RESUMO

The plant microbiota consists of a multitude of microorganisms that can affect plant health and fitness. However, it is currently unclear how the plant shapes its leaf microbiota and what role the plant immune system plays in this process. Here, we evaluated Arabidopsis thaliana mutants with defects in different parts of the immune system for an altered bacterial community assembly using a gnotobiotic system. While higher-order mutants in receptors that recognize microbial features and in defence hormone signalling showed substantial microbial community alterations, the absence of the plant NADPH oxidase RBOHD caused the most pronounced change in the composition of the leaf microbiota. The rbohD knockout resulted in an enrichment of specific bacteria. Among these, we identified Xanthomonas strains as opportunistic pathogens that colonized wild-type plants asymptomatically but caused disease in rbohD knockout plants. Strain dropout experiments revealed that the lack of RBOHD unlocks the pathogenicity of individual microbiota members driving dysbiosis in rbohD knockout plants. For full protection, healthy plants require both a functional immune system and a microbial community. Our results show that the NADPH oxidase RBOHD is essential for microbiota homeostasis and emphasizes the importance of the plant immune system in controlling the leaf microbiota.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/microbiologia , Homeostase , Microbiota , NADPH Oxidases/metabolismo , Arabidopsis/enzimologia , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Bactérias/classificação , Bactérias/crescimento & desenvolvimento , Bactérias/patogenicidade , Fenômenos Fisiológicos Bacterianos , Genótipo , NADPH Oxidases/genética , Fenótipo , Imunidade Vegetal/genética , Folhas de Planta/enzimologia , Folhas de Planta/imunologia , Folhas de Planta/microbiologia
6.
Commun Biol ; 4(1): 865, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34257370

RESUMO

A single-nucleotide polymorphism of neutrophil cytosolic factor 1 (Ncf1), leading to an impaired generation of reactive oxygen species (ROS), is a causative genetic factor for autoimmune disease. To study a possible tumor protection effect by the Ncf1 mutation in a manner dependent on cell types, we used experimental mouse models of lung colonization assay by B16F10 melanoma cells. We observed fewer tumor foci in Ncf1 mutant mice, irrespective of αßT, γδT, B-cell deficiencies, or of a functional Ncf1 expression in CD68-positive monocytes/macrophages. The susceptibility to tumor colonization was restored by the human S100A8 (MRP8) promoter directing a functional Ncf1 expression to granulocytes. This effect was associated with an increase of both ROS and interleukin 1 beta (IL-1ß) production from lung neutrophils. Moreover, neutrophil depletion by anti-Ly6G antibodies increased tumor colonization in wild type but failed in the Ncf1 mutant mice. In conclusion, tumor colonization is counteracted by ROS-activated and IL-1ß-secreting tissue neutrophils.


Assuntos
Regulação Neoplásica da Expressão Gênica , NADPH Oxidases/genética , Neoplasias/genética , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Calgranulina A/genética , Calgranulina A/metabolismo , Linhagem Celular Tumoral , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , NADPH Oxidases/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Polimorfismo de Nucleotídeo Único
7.
Nat Commun ; 12(1): 4327, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267202

RESUMO

Trivalent rare earth elements (REEs) are widely used in agriculture. Aerially applied REEs enter leaf epidermal cells by endocytosis and act systemically to improve the growth of the whole plant. The mechanistic basis of their systemic activity is unclear. Here, we show that treatment of Arabidopsis leaves with trivalent lanthanum [La(III)], a representative of REEs, triggers systemic endocytosis from leaves to roots. La(III)-induced systemic endocytosis requires AtrbohD-mediated reactive oxygen species production and jasmonic acid. Systemic endocytosis impacts the accumulation of mineral elements and the development of roots consistent with the growth promoting effects induced by aerially applied REEs. These findings provide insights into the mechanistic basis of REE activity in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Lantânio/farmacologia , NADPH Oxidases/metabolismo , Arabidopsis/citologia , Proteínas de Arabidopsis/genética , Ciclopentanos/metabolismo , Endocitose/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Fluorescência Verde/genética , Minerais/metabolismo , NADPH Oxidases/genética , Oxilipinas/metabolismo , Células Vegetais/efeitos dos fármacos , Folhas de Planta/citologia , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/citologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Transdução de Sinais
8.
ACS Appl Mater Interfaces ; 13(27): 31452-31461, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34197086

RESUMO

Chemodynamic therapy (CDT) is a promising therapeutic modality with transition metal ions and endogenous H2O2 as reagents, but its efficiency is impaired by low endogenous H2O2 levels and nonregeneration of metal ions. Most intracellular H2O2 supplement strategies use oxidases and are intensively dependent on oxygen participation. The hypoxia microenvironments of solid tumors weaken their performance. Here, we develop a near-infrared II light powered nanoamplifier to improve the local oxygen level and to enhance CDT. The nanoamplifier CPNP-Fc/Pt consists of ferrocene (Fc)- and cisplatin prodrug (Pt(IV))-modified conjugated polymer nanoparticles (CPNPs). CPNP has a donor-acceptor structure and demonstrates a good photothermal effect under 1064 nm light irradiation, which accelerates blood flow and efficiently elevates the local oxygen content. In response to intracellular glutathione, Pt(II) is released from CPNP-Fc/Pt and triggers enzymatic cascade reactions with nicotinamide adenine dinucleotide phosphate oxidase (NADPH oxidase) and superoxide dismutase to convert oxygen into H2O2. The enhanced oxygen level results in efficient intracellular H2O2 supply. Fc is reacted with H2O2 and converted to Fc+ via the Fenton reaction, with the generation of hydroxyl radicals for CDT. Unlike free metal ions, the Fe(III) in Fc+ is reduced to Fe(II) by intracellular NAD(P)H, which achieves the regeneration of Fc. The sufficient intracellular H2O2 supply and efficient Fc regeneration effectively enhance the Fenton reaction and demonstrate good in vivo CDT results with tumor growth suppression. This design offers a promising strategy to enhance CDT efficiency in the hypoxia microenvironment of solid tumors.


Assuntos
Compostos Ferrosos/química , Raios Infravermelhos , Metalocenos/química , Nanomedicina/métodos , Nanopartículas/química , Linhagem Celular Tumoral , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , NADPH Oxidases/metabolismo , Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
9.
Vet Parasitol ; 296: 109502, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34214944

RESUMO

Trypanosoma evansi infects a wide range of hosts to cause huge economic losses in livestock industry. In recent years, it has been demonstrated that neutrophils extracellular traps (NETs) play a critical role in combating parasite infections. However, the role of NETs in the resistance to T. evansi infection is still unclear. In this study, T. evansi induced NETs were observed and their components were determined. The effect of NETs on the viability and motility of T. evansi were estimated. The production of reactive oxygen species (ROS) and Lactate dehydrogenase (LDH) activity in the process of T. evansi-induced NETs formation were detected. The effect of ERK1/2 signaling pathway, neutrophil elastase (NE), myeloperoxidase (MPO), store-operated Ca(2+) entry (SOCE) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase on T. evansi triggered NETs formation were determined. The results showed that neutrophils could release ETs after being stimulated with T. evansi and the structures of NETs mainly consisted of DNA decorated with histone 3 (H3), NE, and MPO. NETs could reduce the parasite motility without affecting the parasite viability. T. evansi-induced NETs formation was dose and time-dependent and was accompanied by ROS production. Inhibitor assays suggested that the formation of NETs induced by T. evansi was dependent on MPO, NE and ERK1/2 signaling pathway but independent on NADPH oxidase and SOCE. In addition, there was no significant changes in LDH activity during NETs formation. This study is the first report of T. evansi-induced NETs formation.


Assuntos
Armadilhas Extracelulares , Transdução de Sinais , Trypanosoma , Tripanossomíase , Animais , Armadilhas Extracelulares/metabolismo , Elastase de Leucócito/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/enzimologia , Peroxidase/metabolismo , Espécies Reativas de Oxigênio , Trypanosoma/metabolismo , Tripanossomíase/imunologia , Tripanossomíase/parasitologia
10.
New Phytol ; 232(1): 318-331, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34133755

RESUMO

Reactive oxygen species (ROS) generated in response to infections often activate immune responses in eukaryotes including plants. In plants, ROS are primarily produced by plasma membrane-bound NADPH oxidases called respiratory burst oxidase homologue (Rboh). Surprisingly, Rbohs can also promote the infection of plants by certain pathogens, including plant parasitic cyst nematodes. The Arabidopsis genome contains 10 Rboh genes (RbohA-RbohJ). Previously, we showed that cyst nematode infection causes a localised ROS burst in roots, mediated primarily by RbohD and RbohF. We also found that plants deficient in RbohD and RbohF (rbohD/F) exhibit strongly decreased susceptibility to cyst nematodes, suggesting that Rboh-mediated ROS plays a role in promoting infection. However, little information is known of the mechanism by which Rbohs promote cyst nematode infection. Here, using detailed genetic and biochemical analyses, we identified WALLS ARE THIN1 (WAT1), an auxin transporter, as a downstream target of Rboh-mediated ROS during parasitic infections. We found that WAT1 is required to modulate the host's indole metabolism, including indole-3-acetic acid levels, in infected cells and that this reprogramming is necessary for successful establishment of the parasite. In conclusion, this work clarifies a unique mechanism that enables cyst nematodes to use the host's ROS for their own benefit.


Assuntos
Proteínas de Arabidopsis , Cistos , Nematoides , Animais , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Indóis , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Nematoides/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
Front Immunol ; 12: 629167, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122402

RESUMO

Neutrophil extracellular traps (NETs) are increasingly recognized to play a role in the pathogenesis of viral infections, including dengue. NETs can be formed NADPH oxidase (NOX)-dependently or NOX-independently. NOX-independent NETs can be induced by activated platelets and are very potent in activating the endothelium. Platelet activation with thrombocytopenia and endothelial dysfunction are prominent features of dengue virus infection. We postulated that dengue infection is associated with NOX-independent NET formation, which is related to platelet activation, endothelial perturbation and increased vascular permeability. Using our specific NET assays, we investigated the time course of NET formation in a cohort of Indonesian dengue patients. We found that plasma levels of NETs were profoundly elevated and that these NETs were predominantly NOX-independent NETs. During early recovery phase (7-13 days from fever onset), total NETs correlated negatively with platelet number and positively with platelet P-selectin expression, the binding of von Willebrand factor to platelets and levels of Syndecan-1. Patients with gall bladder wall thickening, an early marker of plasma leakage, had a higher median level of total NETs. Ex vivo, platelets induced NOX-independent NET formation in a dengue virus non-structural protein 1 (NS1)-dependent manner. We conclude that NOX-independent NET formation is enhanced in dengue, which is most likely mediated by NS1 and activated platelets.


Assuntos
Plaquetas/metabolismo , Vírus da Dengue/patogenicidade , Dengue/enzimologia , Armadilhas Extracelulares/metabolismo , NADPH Oxidases/metabolismo , Neutrófilos/enzimologia , Ativação Plaquetária , Adolescente , Adulto , Plaquetas/imunologia , Plaquetas/virologia , Estudos de Casos e Controles , Células Cultivadas , Dengue/sangue , Dengue/imunologia , Dengue/virologia , Vírus da Dengue/imunologia , Vírus da Dengue/metabolismo , Armadilhas Extracelulares/virologia , Feminino , Interações Hospedeiro-Patógeno , Humanos , Indonésia , Masculino , Neutrófilos/imunologia , Neutrófilos/virologia , Estudos Prospectivos , Proteínas não Estruturais Virais/metabolismo , Adulto Jovem
12.
BMC Plant Biol ; 21(1): 274, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130630

RESUMO

BACKGROUND: Rhizobium-legume symbiosis is a specific, coordinated interaction that results in the formation of a root nodule, where biological nitrogen fixation occurs. NADPH oxidases, or Respiratory Burst Oxidase Homologs (RBOHs) in plants, are enzymes that generate superoxide (O2 •-). Superoxide produces other reactive oxygen species (ROS); these ROS regulate different stages of mutualistic interactions. For example, changes in ROS levels are thought to induce ROS scavenging, cell wall remodeling, and changes in phytohormone homeostasis during symbiotic interactions. In common bean (Phaseolus vulgaris), PvRbohB plays a key role in the early stages of nodulation. RESULTS: In this study, to explore the role of PvRbohB in root nodule symbiosis, we analyzed transcriptomic data from the roots of common bean under control conditions (transgenic roots without construction) and roots with downregulated expression of PvRbohB (by RNA interference) non-inoculated and inoculated with R. tropici. Our results suggest that ROS produced by PvRBOHB play a central role in infection thread formation and nodule organogenesis through crosstalk with flavonoids, carbon metabolism, cell cycle regulation, and the plant hormones auxin and cytokinin during the early stages of this process. CONCLUSIONS: Our findings provide important insight into the multiple roles of ROS in regulating rhizobia-legume symbiosis.


Assuntos
Carbono/metabolismo , Ciclo Celular , NADPH Oxidases/metabolismo , Phaseolus/enzimologia , Nodulação , Raízes de Plantas/enzimologia , Simbiose/fisiologia , Phaseolus/genética , Phaseolus/microbiologia , Raízes de Plantas/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Rhizobium/fisiologia , Transcriptoma
13.
Proc Natl Acad Sci U S A ; 118(27)2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34183391

RESUMO

IgA is the second most abundant antibody present in circulation and is enriched at mucosal surfaces. As such, IgA plays a key role in protection against a variety of mucosal pathogens including viruses. In addition to neutralizing viruses directly, IgA can also stimulate Fc-dependent effector functions via engagement of Fc alpha receptors (Fc-αRI) expressed on the surface of certain immune effector cells. Neutrophils are the most abundant leukocyte, express Fc-αRI, and are often the first to respond to sites of injury and infection. Here, we describe a function for IgA-virus immune complexes (ICs) during viral infections. We show that IgA-virus ICs potentiate NETosis-the programmed cell-death pathway through which neutrophils release neutrophil extracellular traps (NETs). Mechanistically, IgA-virus ICs potentiated a suicidal NETosis pathway via engagement of Fc-αRI on neutrophils through a toll-like receptor-independent, NADPH oxidase complex-dependent pathway. NETs also were capable of trapping and inactivating viruses, consistent with an antiviral function.


Assuntos
Armadilhas Extracelulares/imunologia , Imunoglobulina A/imunologia , Neutrófilos/imunologia , Viroses/imunologia , Complexo Antígeno-Anticorpo/imunologia , Antígenos CD/metabolismo , Armadilhas Extracelulares/virologia , Humanos , Influenzavirus A/imunologia , NADPH Oxidases/metabolismo , Neutrófilos/patologia , Neutrófilos/virologia , Receptores Fc/metabolismo , SARS-CoV-2/imunologia , Transdução de Sinais , Vírion
14.
Cancer Sci ; 112(7): 2803-2820, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34109710

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is one of the most chemoresistant cancers. An understanding of the molecular mechanism by which PDAC cells have a high chemoresistant potential is important for improvement of the poor prognosis of patients with PDAC. Here we show for the first time that disruption of heat shock protein 47 (HSP47) enhances the efficacy of the therapeutic agent gemcitabine for PDAC cells and that the efficacy is suppressed by reconstituting HSP47 expression. HSP47 interacts with calreticulin (CALR) and the unfolded protein response transducer IRE1α in PDAC cells. Ablation of HSP47 promotes both the interaction of CALR with sarcoplasmic/endoplasmic reticulum Ca2+ -ATPase 2 and interaction of IRE1α with inositol 1,4,5-triphosphate receptor, which generates a condition in which an increase in intracellular Ca2+ level is prone to be induced by oxidative stimuli. Disruption of HSP47 enhances NADPH oxidase-induced generation of intracellular reactive oxygen species (ROS) and subsequent increase in intracellular Ca2+ level in PDAC cells after treatment with gemcitabine, resulting in the death of PDAC cells by activation of the Ca2+ /caspases axis. Ablation of HSP47 promotes gemcitabine-induced suppression of tumor growth in PDAC cell-bearing mice. Overall, these results indicated that HSP47 confers chemoresistance on PDAC cells and suggested that disruption of HSP47 may improve the efficacy of chemotherapy for patients with PDAC.


Assuntos
Calreticulina/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Resistencia a Medicamentos Antineoplásicos , Endorribonucleases/metabolismo , Proteínas de Choque Térmico HSP47/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Antimetabólitos Antineoplásicos/uso terapêutico , Cálcio/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Caspases/metabolismo , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Técnicas de Inativação de Genes , Inativação Gênica , Proteínas de Choque Térmico HSP47/genética , Xenoenxertos , Humanos , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Camundongos , NADPH Oxidases/metabolismo , Transplante de Neoplasias , Neoplasias Pancreáticas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Resposta a Proteínas não Dobradas
15.
Int J Mol Sci ; 22(10)2021 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064664

RESUMO

Rutin is a flavonoid with antioxidant property. It has been shown to exert cardioprotection against cardiomyocyte hypertrophy. However, studies regarding its antihypertrophic property are still lacking, whether it demonstrates similar antihypertrophic effect to its metabolite, quercetin. Hence, this study aimed to investigate the effects of both flavonoids on oxidative stress and mitogen-activated protein kinase (MAPK) pathway in H9c2 cardiomyocytes that were exposed to angiotensin II (Ang II) to induce hypertrophy. Cardiomyocytes were exposed to Ang II (600 nM) with or without quercetin (331 µM) or rutin (50 µM) for 24 h. A group given vehicle served as the control. The concentration of the flavonoids was chosen based on the reported effective concentration to reduce cell hypertrophy or cardiac injury in H9c2 cells. Exposure to Ang II increased cell surface area, intracellular superoxide anion level, NADPH oxidase and inducible nitric oxide synthase activities, and reduced cellular superoxide dismutase activity and nitrite level, which were similarly reversed by both rutin and quercetin. Rutin had no significant effects on phosphorylated proteins of extracellular signal-related kinases (ERK1/2) and p38 but downregulated phosphorylated c-Jun N-terminal kinases (JNK1/2), which were induced by Ang II. Quercetin, on the other hand, had significantly downregulated the phosphorylated proteins of ERK1/2, p38, and JNK1/2. The quercetin inhibitory effect on JNK1/2 was stronger than the rutin. In conclusion, both flavonoids afford similar protective effects against Ang II-induced cardiomyocyte hypertrophy, but they differently modulate MAPK pathway.


Assuntos
Angiotensina II/toxicidade , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Hipertrofia/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mioblastos Cardíacos/metabolismo , Quercetina/farmacologia , Rutina/farmacologia , Animais , Antioxidantes/farmacologia , Células Cultivadas , Hipertrofia/induzido quimicamente , Hipertrofia/tratamento farmacológico , Hipertrofia/patologia , Proteínas Quinases Ativadas por Mitógeno/genética , Mioblastos Cardíacos/citologia , Mioblastos Cardíacos/efeitos dos fármacos , NADPH Oxidases/metabolismo , Óxido Nítrico/metabolismo , Fosforilação , Ratos , Espécies Reativas de Oxigênio/metabolismo , Vasoconstritores/toxicidade
16.
BMC Cardiovasc Disord ; 21(1): 302, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130633

RESUMO

BACKGROUND: Duchenne muscular dystrophy (DMD) associated cardiomyopathy is a major cause of morbidity and mortality. In an in vitro DMD cardiomyocyte model, nicorandil reversed stress-induced cell injury through multiple pathways implicated in DMD. We aimed to test the efficacy of nicorandil on the progression of cardiomyopathy in mdx mice following a 10-day treatment protocol. METHODS: A subset of mdx mice was subjected to low-dose isoproterenol injections over 5 days to induce a cardiac phenotype and treated with vehicle or nicorandil for 10 days. Baseline and day 10 echocardiograms were obtained to assess cardiac function. At 10 days, cardiac tissue was harvested for further analysis, which included histologic analysis and assessment of oxidative stress. Paired student's t test was used for in group comparison, and ANOVA was used for multiple group comparisons. RESULTS: Compared to vehicle treated mice, isoproterenol decreased ejection fraction and fractional shortening on echocardiogram. Nicorandil prevented isoproterenol induced cardiac dysfunction. Isoproterenol increased cardiac fibrosis, which nicorandil prevented. Isoproterenol increased gene expression of NADPH oxidase, which decreased to baseline with nicorandil treatment. Superoxide dismutase 2 protein expression increased in those treated with nicorandil, and xanthine oxidase activity decreased in mice treated with nicorandil during isoproterenol stress compared to all other groups. CONCLUSIONS: In conclusion, nicorandil is cardioprotective in mdx mice and warrants continued investigation as a therapy for DMD associated cardiomyopathy.


Assuntos
Cardiomiopatias/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Nicorandil/farmacologia , Volume Sistólico/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/metabolismo , Cardiomiopatias/fisiopatologia , Modelos Animais de Doenças , Feminino , Fibrose , Isoproterenol , Camundongos Endogâmicos mdx , Distrofia Muscular de Duchenne/complicações , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Xantina Oxidase/metabolismo
17.
Infect Immun ; 89(7): e0073820, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-33941576

RESUMO

Trypanosoma cruzi is the intracellular parasite of Chagas disease, a chronic condition characterized by cardiac and gastrointestinal morbidity. Protective immunity requires CD4+ T cells, and Th1 cells and gamma interferon (IFN-γ) are important players in host defense. More recently, Th17 cells and interleukin 17A (IL-17A) have been shown to exert protective functions in systemic T. cruzi infection. However, it remains unclear whether Th17 cells and IL-17A protect in the mucosa, the initial site of parasite invasion in many human cases. We found that IL-17RA knockout (KO) mice are highly susceptible to orogastric infection, indicating an important function for this cytokine in mucosal immunity to T. cruzi. To investigate the specific role of Th17 cells for mucosal immunity, we reconstituted RAG1 KO mice with T. cruzi-specific T cell receptor transgenic Th17 cells prior to orogastric T. cruzi challenges. We found that Th17 cells provided protection against gastric mucosal T. cruzi infection, indicated by significantly lower stomach parasite burdens. In vitro macrophage infection assays revealed that protection by Th17 cells is reduced with IL-17A neutralization or reversed by loss of macrophage NADPH oxidase activity. Consistently with this, mice lacking functional NADPH oxidase were not protected by Th17 cell transfer. These data are the first report that Th17 cells protect against mucosal T. cruzi infection and identify a novel protective mechanism involving the induction of NADPH oxidase activity by IL-17A. These studies provide important insights for Chagas vaccine development and, more broadly, increase our understanding of the diverse roles of Th17 cells in host defense.


Assuntos
Doença de Chagas/imunologia , Mucosa Gástrica/imunologia , Mucosa Gástrica/parasitologia , Interações Hospedeiro-Parasita/imunologia , Imunidade nas Mucosas , Células Th17/imunologia , Trypanosoma cruzi/imunologia , Animais , Doença de Chagas/metabolismo , Doença de Chagas/parasitologia , Modelos Animais de Doenças , Interleucina-17/genética , Interleucina-17/metabolismo , Ativação Linfocitária/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Camundongos , Camundongos Knockout , NADPH Oxidases/metabolismo , Células Th17/metabolismo
18.
Vascul Pharmacol ; 139: 106879, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34051372

RESUMO

Toll-like receptor 4 (TLR4) contributes to the pathophysiology of diabetes. This happens, at least in part, because TLR4 modulates the enzyme NADPH oxidase, a primary source of ROS in vascular structures. Increased oxidative stress disrupts key vascular signaling mechanisms and drives the progression of diabetes, elevating the likelihood of cardiovascular diseases. Recently, it has been shown that patients with diabetes are also at a higher risk of developing severe coronavirus disease 2019 (COVID-19). Given the importance of the interaction between TLR4 and NADPH oxidase to the disrupted diabetic vascular system, we put forward the hypothesis that TLR4-mediated NADPH oxidase-derived ROS might be a critical mechanism to help explain why this disparity appears in diabetic patients, but unfortunately, conclusive experimental evidence still lacks in the literature. Herein, we focus on discussing the pathological implications of this signaling communication in the diabetic vasculature and exploring this crosstalk in the context of diabetes-associated severe COVID-19.


Assuntos
Vasos Sanguíneos/enzimologia , COVID-19/virologia , Diabetes Mellitus/enzimologia , Angiopatias Diabéticas/enzimologia , NADPH Oxidases/metabolismo , SARS-CoV-2/patogenicidade , Receptor 4 Toll-Like/metabolismo , Animais , Vasos Sanguíneos/fisiopatologia , Vasos Sanguíneos/virologia , COVID-19/enzimologia , COVID-19/fisiopatologia , Diabetes Mellitus/fisiopatologia , Angiopatias Diabéticas/fisiopatologia , Ativação Enzimática , Interações Hospedeiro-Patógeno , Humanos , Estresse Oxidativo , Prognóstico , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
19.
Oxid Med Cell Longev ; 2021: 7086512, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953837

RESUMO

NADPH oxidase as an important source of intracellular reactive oxygen species (ROS) has gained enormous importance over the years, and the detailed structures of all the isoenzymes of the NADPH oxidase family and their regulation have been well explored. The enzyme has been implicated in a variety of diseases including neurodegenerative diseases. The present brief review examines the body of evidence that links NADPH oxidase with the genesis and progression of Alzheimer's disease (AD). In short, evidence suggests that microglial activation and inflammatory response in the AD brain is associated with increased production of ROS by microglial NADPH oxidase. Along with other inflammatory mediators, ROS take part in neuronal degeneration and enhance the microglial activation process. The review also evaluates the current state of NADPH oxidase inhibitors as potential disease-modifying agents for AD.


Assuntos
Doença de Alzheimer/genética , Mediadores da Inflamação/fisiologia , NADPH Oxidases/metabolismo , Estresse Oxidativo/genética , Animais , Humanos , Camundongos , Ratos
20.
Free Radic Biol Med ; 171: 345-364, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34019933

RESUMO

Heart failure is a growing health burden worldwide characterized by alterations in excitation-contraction coupling, cardiac energetic deficit and oxidative stress. While current treatments are mostly limited to antagonization of neuroendocrine activation, more recent data suggest that also targeting metabolism may provide substantial prognostic benefit. However, although in a broad spectrum of preclinical models, oxidative stress plays a causal role for the development and progression of heart failure, no treatment that targets reactive oxygen species (ROS) directly has entered the clinical arena yet. In the heart, ROS derive from various sources, such as NADPH oxidases, xanthine oxidase, uncoupled nitric oxide synthase and mitochondria. While mitochondria are the primary source of ROS in the heart, communication between different ROS sources may be relevant for physiological signalling events as well as pathologically elevated ROS that deteriorate excitation-contraction coupling, induce hypertrophy and/or trigger cell death. Here, we review the sources of ROS in the heart, the modes of pathological activation of ROS formation as well as therapeutic approaches that may target ROS specifically in mitochondria.


Assuntos
Insuficiência Cardíaca , Insuficiência Cardíaca/terapia , Humanos , NADPH Oxidases/metabolismo , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio
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