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1.
Cancers (Basel) ; 15(14)2023 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-37509346

RESUMEN

BEND3 is a transcription factor that plays a critical role in the regulation of gene expression in mammals. While there is limited research on the role of BEND3 as a tumor suppressor or an oncogene and its potential role in cancer therapy is still emerging, several studies suggest that it may be involved in both the processes. Its interaction and regulation with multiple other factors via p21 have already been reported to play a significant role in cancer development, which serves as an indication of its potential role in oncogenesis. Its interaction with chromatin modifiers such as NuRD and NoRC and its role in the recruitment of polycomb repressive complex 2 (PRC2) are some of the additional events indicative of its potential role in cancer development. Moreover, a few recent studies indicate BEND3 as a potential target for cancer therapy. Since the specific mechanisms by which BEND3 may contribute to cancer progression are not yet fully elucidated, in this review, we have discussed the possible pathways BEND3 may take to serve as an oncogenic driver or suppressor.

2.
Mater Today Proc ; 79: 6-10, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35946044

RESUMEN

Due to the recent pandemic situation that has erupted all around us, healthcare facility design is a must. Healthcare providers and administrators must concentrate on the changes that must be made in existing healthcare facilities. The isolated healthcare facilities are essential because the corona virus is spread mainly through close contact (within six feet), such as handshaking (if someone's hands are infected) or touching contaminated surfaces. Healthcare facilities are most susceptible to the spread of the corona virus due to the high number of symptomatic patients admitted. Coronavirus is the leading cause of infectious disease morbidity and mortality worldwide. Thus, if the pandemic situation worsens, new plans and designs for existing healthcare facilities will be required, as well as temporary versions. Societal gains from increased research in this area. In the coming years, healthcare workers will be better trained, and healthcare facilities will be upgraded. This paper proposes new plans and designs to address the issues raised.

3.
Bioresour Technol ; 357: 127377, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35642854

RESUMEN

In this work, a cascaded control strategy based on fractional-order fuzzy PD/PI (FOFPD/PI) is proposed for temperature control of the bioreactor. The FOFPI is used to control the ethanol concentration in the inner loop, while the FOFPD is used for temperature control of the bioreactor in the outer loop. The integer order fuzzy PD/PI (IOFPD/PI), 2DOF FOPID, 2DOF PID, and PID are also designed for comparison purposes. The design parameter of FOFPD/PI and IOFPD/PI are estimated using non-dominated sorting genetic algorithm II (NSGA-II). Results revealed that the proposed cascaded control scheme reduced the IAE by 33.5 %, 40.5%, 47%, and 64% compared to IOFPD/PI, 2DOF FOPID, 2DOF PID, and PID, respectively. Hence, it can be concluded that the proposed FOFPD/PI controller provides precise control of reactor temperature in different operating conditions compared to other controllers.


Asunto(s)
Algoritmos , Reactores Biológicos , Simulación por Computador , Fermentación , Temperatura
4.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35217604

RESUMEN

BEN domain-containing proteins are emerging rapidly as an important class of factors involved in modulating gene expression, yet the molecular basis of how they regulate chromatin function and transcription remains to be established. BEND3 is a quadruple BEN domain-containing protein that associates with heterochromatin and functions as a transcriptional repressor. We find that BEND3 is highly expressed in pluripotent cells, and the induction of differentiation results in the down-regulation of BEND3. The removal of BEND3 from pluripotent cells results in cells exhibiting upregulation of the differentiation-inducing gene expression signature. We find that BEND3 binds to the promoters of differentiation-associated factors and key cell cycle regulators, including CDKN1A, encoding the cell cycle inhibitor p21, and represses the expression of differentiation-associated genes by enhancing H3K27me3 decoration at these promoters. Our results support a model in which transcription repression mediated by BEND3 is essential for normal development and to prevent differentiation.


Asunto(s)
Diferenciación Celular/genética , Células Madre Pluripotentes/citología , Proteínas Represoras/fisiología , G-Cuádruplex , Regulación de la Expresión Génica , Humanos , Regiones Promotoras Genéticas
5.
Sensors (Basel) ; 22(1)2022 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-35009896

RESUMEN

Trilateration-based target localization using received signal strength (RSS) in a wireless sensor network (WSN) generally yields inaccurate location estimates due to high fluctuations in RSS measurements in indoor environments. Improving the localization accuracy in RSS-based systems has long been the focus of a substantial amount of research. This paper proposes two range-free algorithms based on RSS measurements, namely support vector regression (SVR) and SVR + Kalman filter (KF). Unlike trilateration, the proposed SVR-based localization scheme can directly estimate target locations using field measurements without relying on the computation of distances. Unlike other state-of-the-art localization and tracking (L&T) schemes such as the generalized regression neural network (GRNN), SVR localization architecture needs only three RSS measurements to locate a mobile target. Furthermore, the SVR based localization scheme was fused with a KF in order to gain further refinement in target location estimates. Rigorous simulations were carried out to test the localization efficacy of the proposed algorithms for noisy radio frequency (RF) channels and a dynamic target motion model. Benefiting from the good generalization ability of SVR, simulation results showed that the presented SVR-based localization algorithms demonstrate superior performance compared to trilateration- and GRNN-based localization schemes in terms of indoor localization performance.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Simulación por Computador , Movimiento (Física) , Ondas de Radio
6.
Cancer Metab ; 9(1): 39, 2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34749809

RESUMEN

BACKGROUND: Pyruvate dehydrogenase complex (PDC) plays a central role in carbohydrate metabolism, linking cytoplasmic glycolysis to the mitochondrial tricarboxylic acid (TCA) cycle. PDC is a conserved E1-E2-E3 dehydrogenase with a PDHA1 and PDHB heterotetramer functioning as the E1 subunit. PDHA1 contains three serine residues that can be reversibly phosphorylated by a dedicated family of four inhibitory pyruvate dehydrogenase kinases (PDHK1-4) and two reactivating phosphatases (PDP1, 2). Hypoxia induces the expression of PDHK1 and PDHK3 and hyperphosphorylates PDHA1. The role of PDC in metabolic reprogramming and tumor progression appears to be for the integration of oncogenic and environmental signals which supports tumor growth. METHODS: To isolate the function of the serine-dependent regulation of PDC, we engineered MiaPaca2 cells to express PDHA1 protein with either intact serines at positions 232, 293, and 300 or all the combinations of non-phosphorylatable alanine substitution mutations. These lines were compared in vitro for biochemical response to hypoxia by western blot, metabolic activity by biochemical assay and Seahorse XF flux analysis, and growth in media with reduced exogenous metabolites. The lines were also tested for growth in vivo after orthotopic injection into the pancreata of immune-deficient mice. RESULTS: In this family of cells with non-phosphorylatable PDHA1, we found reduced hypoxic phosphorylation of PDHA1, decreased PDH enzymatic activity in normoxia and hypoxia, decreased mitochondrial function by Seahorse flux assay, reduced in vitro growth of cells in media depleted of lipids, and reduced growth of tumors after orthotopic transplantation of cells into the pancreata of immune-deficient mice. CONCLUSIONS: We found that any substitution of alanine for serine at regulatory sites generated a hypomorphic PDC. However, the reduced PDC activity was insensitive to further reduction in hypoxia. These cells had a very modest reduction of growth in vitro, but failed to grow as tumors indicating that dynamic PDC adaptation to microenvironmental conditions is necessary to support pancreatic cancer growth in vivo.

7.
J Pharmacokinet Pharmacodyn ; 48(4): 543-562, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33751365

RESUMEN

This work is focused on multi-objective optimisation of a multi-drug chemotherapy schedule for cell-cycle-specific cancer treatment under the influence of drug resistance. The acquired drug resistance to chemotherapeutic agents is incorporated into the existing compartmental model of breast cancer. Furthermore, the toxic effect of drugs on healthy cells and overall drug concentration in the patient body are also constrained in the proposed model. The objective is to determine the optimal drug schedule according to the patient's physiological condition so that the tumour burden is minimised. A multi-objective optimisation algorithm, non-dominated sorting genetic algorithm-II (NSGA-II) is utilised to solve the problem. The obtained results are thoroughly analysed to illustrate the impact of drug resistance on the treatment. The capability of optimised schedules to deal with parametric uncertainty is also analysed. The drug schedules obtained in this work align well with the clinical standards. It is also revealed that the NSGA-II optimised drug schedule with proper rest period between successive dosages yields the minimum cancer load at the end of the treatment.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ciclo Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Algoritmos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Resistencia a Antineoplásicos , Humanos , Modelos Estadísticos
8.
J Breath Res ; 13(4): 046005, 2019 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-31170701

RESUMEN

This work demonstrates the development of Ag@polyaniline/multi-walled carbon nanotube nanocomposite-based sensor strips and a suitable integrated electronic read-out system for the measurement of trace-level concentrations of ammonia (NH3). The sensor is optimized under various operating conditions and the resulting sensor exhibited an enhanced response (32% for 2 ppm) with excellent selectivity. Stable performance was observed towards NH3 in the presence of high concentrations of CO2 (>40 000 ppm), simulated and real breath samples. A suitable electronic sensor read-out system has also been designed and developed based on multi-scale resistance-to-voltage conversion architecture, processed by a 32-bit microcontroller which is operatable over a wide range of sensor resistance (1 kΩ to 200 MΩ). As a proof of concept, integration of gas-sensing strips with the electronic read-out system was tested with various levels of NH3 (<2 ppm as normal, >2 ppm as critical and 2 ppm as threshold), which is important for clinical breath analyzer applications. The developed prototype device can be readily incorporated into a portable, low-cost and non-invasive point-of-care breath NH3 detection unit for portable pre-diagnostic breath analyzer applications.


Asunto(s)
Amoníaco/análisis , Pruebas Respiratorias/métodos , Costos y Análisis de Costo , Nanotubos de Carbono/química , Compuestos de Anilina/química , Dióxido de Carbono/farmacología , Simulación por Computador , Humanos , Humedad , Nanocompuestos/química , Reproducibilidad de los Resultados , Plata/química
9.
J Family Med Prim Care ; 8(1): 171-177, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30911501

RESUMEN

INTRODUCTION: Complaints of arm, neck, and shoulders (CANS) is a common problem among patients whose work involves computer use, but often ignored most importantly by the physicians partly due to not being able to appreciate the importance of taking a careful detailed occupational history of exposure to a repetitive activity involving upper arms. Upper extremity musculoskeletal disorders constitute a major portion of occupation-related illness with annual costs related to treatment and absenteeism from work ranging between $45 and 54 billion in the United States. MATERIALS AND METHODS: A cross-sectional study was done to assess the factors contributing to CANS among computer professionals in Bangalore. We screened 206 professionals and 181 were administered Maastricht Upper Extremity Questionnaire (MUEQ). Chi-square and logistic regression were used. RESULTS: Prevalence of CANS in the study group was 58.6%. Neck complaints topped the list followed by shoulder, wrist, hand, elbow, upper arm, and lower arm complaints in the descending order. Women had overall higher prevalence and significantly higher prevalence of upper limb complaints than men. Inadequate space, maintaining good posture, and repetition of same tasks have emerged as an independent factors associated with CANS. CONCLUSION: CANS is highly prevalent among computer professionals working in small and medium-sized companies. Provision of adequate workspace and ergonomic designs of workstations are the modifiable risk factors which can be addressed by the employers to reduce the morbidity associated with CANS. Employees could correct postures and improve work habits.

10.
Biochem Biophys Res Commun ; 477(4): 1065-1071, 2016 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-27402273

RESUMEN

Lung cancer is the most frequently diagnosed malignancy that contributes to high proportion of deaths globally among patients who die due to cancer. Chemotherapy remains the common mode of treatment for lung cancer patients though with limited success. We assessed the biological effects and associated molecular changes of evodiamine, a plant alkaloid, on human lung cancer A549 and H1299 cells along with other epithelial cancer and normal lung SAEC cells. Our data showed that 20-40 µM evodiamine treatment for 24-48 h strongly (up to 73%, P < 0.001) reduced the growth and survival of these cancer cells. However, it also moderately inhibited growth and survival of SAEC cells. A strong inhibition (P < 0.001) was observed on clonogenicity of A549 cells. Further, evodiamine increased (4-fold) mitochondrial membrane depolarization with 6-fold increase in apoptosis and a slight increase in Bax/Bcl-2 ratio. It increased the cytochrome-c release from mitochondria into the cytosol as well as nucleus. Cytosolic cytochrome-c activated cascade of caspase-9 and caspase-3 intrinsic pathway, however, DR5 and caspase-8 extrinsic pathway was also activated which could be due to nuclear cytochrome-c. Pan-caspase inhibitor (z-VAD.fmk) partially reversed evodiamine induced apoptosis. An increase in p53 as well as its serine 15 phosphorylation was also observed. Pifithrin-α, a p53 inhibitor, slightly inhibited growth of A549 cells and under p53 inhibitory condition evodiamine-induced apoptosis could not be reversed. Together these findings suggest that evodiamine is a strong inducer of apoptosis in lung epithelial cancer cells independent of their p53 status and that could involve both intrinsic as well as extrinsic pathway of apoptosis. Thus evodiamine could be a potential anticancer agent against lung cancer.


Asunto(s)
Núcleo Celular/metabolismo , Citocromos c/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Quinazolinas/administración & dosificación , Proteína p53 Supresora de Tumor/metabolismo , Células A549 , Alcaloides/administración & dosificación , Antineoplásicos/administración & dosificación , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Neoplasias Pulmonares/patología , Señales de Localización Nuclear/efectos de los fármacos , Distribución Tisular , Resultado del Tratamiento
11.
J Biol Chem ; 289(19): 13476-91, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24634221

RESUMEN

Hepatocyte growth factor (HGF) mediated signaling promotes cell proliferation and migration in a variety of cell types and plays a key role in tumorigenesis. As cell migration is important to angiogenesis, we characterized HGF-mediated effects on the formation of lamellipodia, a pre-requisite for migration using human lung microvascular endothelial cells (HLMVECs). HGF, in a dose-dependent manner, induced c-Met phosphorylation (Tyr-1234/1235, Tyr-1349, Ser-985, Tyr-1003, and Tyr-1313), activation of PI3k (phospho-Yp85) and Akt (phospho-Thr-308 and phospho-Ser-473) and potentiated lamellipodia formation and HLMVEC migration. Inhibition of c-Met kinase by SU11274 significantly attenuated c-Met, PI3k, and Akt phosphorylation, suppressed lamellipodia formation and endothelial cell migration. LY294002, an inhibitor of PI3k, abolished HGF-induced PI3k (Tyr-458), and Akt (Thr-308 and Ser-473) phosphorylation and suppressed lamellipodia formation. Furthermore, HGF stimulated p47(phox)/Cortactin/Rac1 translocation to lamellipodia and ROS generation. Moreover, inhibition of c-Met/PI3k/Akt signaling axis and NADPH oxidase attenuated HGF- induced lamellipodia formation, ROS generation and cell migration. Ex vivo experiments with mouse aortic rings revealed a role for c-Met signaling in HGF-induced sprouting and lamellipodia formation. Taken together, these data provide evidence in support of a significant role for HGF-induced c-Met/PI3k/Akt signaling and NADPH oxidase activation in lamellipodia formation and motility of lung endothelial cells.


Asunto(s)
Células Endoteliales/metabolismo , Factor de Crecimiento de Hepatocito/metabolismo , Pulmón/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-met/metabolismo , Seudópodos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/fisiología , Animales , Células Cultivadas , Células Endoteliales/citología , Factor de Crecimiento de Hepatocito/genética , Humanos , Pulmón/citología , Ratones , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-met/genética , Seudópodos/genética
12.
Brain Res ; 1543: 93-100, 2014 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-24183785

RESUMEN

Sensory deprivation, such as whisker deprivation, is one of the most common paradigms used to examine experience-dependent plasticity. Many of these studies conducted during development have demonstrated anatomical and synaptic neocortical plasticity with varying lengths of deprivation (for review, see Holtmaat and Svoboda, 2009). However, to date, there have been few studies exploring brief periods of experience-dependent neocortical plasticity in adulthood, similar to that observed from learning and memory paradigms (Siucinska and Kossut, 1996, 2004; Galvez et al., 2006; Chau et al., 2013). Examining both synapsin I and Golgi-Cox stained neurons in primary somatosensory cortex of unilaterally whisker-deprived adult mice, the current study demonstrates that 5 days of whisker deprivation results in more synapses in spared barrels and reduced synapses in deprived barrels. To our knowledge, this is the first study to characterize anatomical changes in layer IV of primary somatosensory cortex after a brief period of sensory deprivation in adulthood. Furthermore, findings from the present study suggest that analyses from prolonged periods of either sensory deprivation or stimulation during adulthood are missing forms of plasticity that could provide better insight into various cognitive processes, such as learning and memory.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Plasticidad Neuronal/fisiología , Neuronas/fisiología , Corteza Somatosensorial/citología , Análisis de Varianza , Animales , Espinas Dendríticas/fisiología , Espinas Dendríticas/ultraestructura , Complejo IV de Transporte de Electrones/metabolismo , Ratones , Ratones Endogámicos C57BL , Neuronas/ultraestructura , Estimulación Física , Privación Sensorial/fisiología , Tinción con Nitrato de Plata , Corteza Somatosensorial/fisiología , Sinapsinas/metabolismo , Factores de Tiempo , Vibrisas/inervación
13.
Am J Pathol ; 183(4): 1169-1182, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23933064

RESUMEN

Bronchopulmonary dysplasia of the premature newborn is characterized by lung injury, resulting in alveolar simplification and reduced pulmonary function. Exposure of neonatal mice to hyperoxia enhanced sphingosine-1-phosphate (S1P) levels in lung tissues; however, the role of increased S1P in the pathobiological characteristics of bronchopulmonary dysplasia has not been investigated. We hypothesized that an altered S1P signaling axis, in part, is responsible for neonatal lung injury leading to bronchopulmonary dysplasia. To validate this hypothesis, newborn wild-type, sphingosine kinase1(-/-) (Sphk1(-/-)), sphingosine kinase 2(-/-) (Sphk2(-/-)), and S1P lyase(+/-) (Sgpl1(+/-)) mice were exposed to hyperoxia (75%) from postnatal day 1 to 7. Sphk1(-/-), but not Sphk2(-/-) or Sgpl1(+/-), mice offered protection against hyperoxia-induced lung injury, with improved alveolarization and alveolar integrity compared with wild type. Furthermore, SphK1 deficiency attenuated hyperoxia-induced accumulation of IL-6 in bronchoalveolar lavage fluids and NADPH oxidase (NOX) 2 and NOX4 protein expression in lung tissue. In vitro experiments using human lung microvascular endothelial cells showed that exogenous S1P stimulated intracellular reactive oxygen species (ROS) generation, whereas SphK1 siRNA, or inhibitor against SphK1, attenuated hyperoxia-induced S1P generation. Knockdown of NOX2 and NOX4, using specific siRNA, reduced both basal and S1P-induced ROS formation. These results suggest an important role for SphK1-mediated S1P signaling-regulated ROS in the development of hyperoxia-induced lung injury in a murine neonatal model of bronchopulmonary dysplasia.


Asunto(s)
Displasia Broncopulmonar/enzimología , Displasia Broncopulmonar/prevención & control , Hiperoxia/complicaciones , Lisofosfolípidos/metabolismo , Glicoproteínas de Membrana/metabolismo , NADPH Oxidasas/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/deficiencia , Esfingosina/análogos & derivados , Aldehído-Liasas/deficiencia , Aldehído-Liasas/metabolismo , Animales , Animales Recién Nacidos , Displasia Broncopulmonar/etiología , Displasia Broncopulmonar/patología , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Células Endoteliales/enzimología , Células Endoteliales/patología , Humanos , Hiperoxia/enzimología , Hiperoxia/patología , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasa 2 , NADPH Oxidasa 4 , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Neumonía/complicaciones , Neumonía/patología , Alveolos Pulmonares/enzimología , Alveolos Pulmonares/patología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Esfingosina/metabolismo , Proteína de Unión al GTP rac1/metabolismo
14.
PLoS One ; 8(5): e63007, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23667561

RESUMEN

Coronins are a highly conserved family of actin binding proteins that regulate actin-dependent processes such as cell motility and endocytosis. We found that treatment of human pulmonary artery endothelial cells (HPAECs) with the bioactive lipid, sphingosine-1-phosphate (S1P) rapidly stimulates coronin 1B translocation to lamellipodia at the cell leading edge, which is required for S1P-induced chemotaxis. Further, S1P-induced chemotaxis of HPAECs was attenuated by pretreatment with small interfering RNA (siRNA) targeting coronin 1B (∼36%), PLD2 (∼45%) or Rac1 (∼50%) compared to scrambled siRNA controls. Down regulation PLD2 expression by siRNA also attenuated S1P-induced coronin 1B translocation to the leading edge of the cell periphery while PLD1 silencing had no effect. Also, S1P-induced coronin 1B redistribution to cell periphery and chemotaxis was attenuated by inhibition of Rac1 and over-expression of dominant negative PKC δ, ε and ζ isoforms in HPAECs. These results demonstrate that S1P activation of PLD2, PKC and Rac1 is part of the signaling cascade that regulates coronin 1B translocation to the cell periphery and the ensuing cell chemotaxis.


Asunto(s)
Quimiotaxis/fisiología , Células Endoteliales/fisiología , Proteínas de Microfilamentos/metabolismo , Arteria Pulmonar/citología , Transducción de Señal/fisiología , Western Blotting , Células Cultivadas , Quimiotaxis/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Lisofosfolípidos/farmacología , Proteínas de Microfilamentos/genética , Microscopía Fluorescente , Fosfolipasa D/metabolismo , Proteína Quinasa C/metabolismo , Transporte de Proteínas/efectos de los fármacos , Interferencia de ARN , ARN Interferente Pequeño/genética , Esfingosina/análogos & derivados , Esfingosina/farmacología , Proteína de Unión al GTP rac1/metabolismo
15.
Am J Respir Cell Mol Biol ; 48(4): 477-88, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23306835

RESUMEN

Earlier studies indicated a role for reactive oxygen species (ROS) in host defense against Pseudomonas aeruginosa infection. However, the role of nicotinamide adenine dinucleotide phosphate-reduced (NADPH) oxidase (NOX) proteins and the mechanism of activation for NADPH oxidase in P. aeruginosa infection are not well-defined. Here, we investigated the role of NOX2 and NOX4 proteins in P. aeruginosa infection, ROS generation, and endothelial barrier function in murine lungs and in human lung microvascular endothelial cells (HLMVECs). Airway instillation of P. aeruginosa strain 103 (PA103) significantly increased ROS concentrations in bronchial alveolar lavage (BAL) fluid, along with the expression of NOX2 and NOX4, but not NOX1 and NOX3, in lung tissue. In addition, PA103-infected HLMVECs revealed elevated concentrations of ROS, NOX2, and NOX4. In murine lungs and HLMVECs, PA103 induced the NF-κB pathway, and its inhibition blocked PA103-dependent NOX2 and NOX4 expression. Barrier function analysis showed that heat-killed PA103 induced endothelial permeability in a dose-dependent manner, which was attenuated by treatment with small interfering (si)RNA specific for NOX4, but not NOX2. Furthermore, the knockdown of NOX4, but not NOX2, with siRNA reduced PA103-mediated apoptosis in HLMVECs. In vivo, the down-regulation of NOX4 with NOX4 siRNA attenuated PA103-induced lung vascular permeability. The deletion of NOX2 in mice exerted no effect on permeability, but offered significant resistance to P. aeruginosa-induced lung inflammation. These data show that P. aeruginosa lung infection up-regulates NOX2 and NOX4 expression and ROS generation, which play distinct roles in regulating lung inflammation, apoptosis, and permeability.


Asunto(s)
Permeabilidad Capilar , Glicoproteínas de Membrana/biosíntesis , NADPH Oxidasas/biosíntesis , NADP/metabolismo , Neumonía Bacteriana/enzimología , Infecciones por Pseudomonas/enzimología , Pseudomonas aeruginosa , Animales , Barrera Alveolocapilar/enzimología , Barrera Alveolocapilar/patología , Células Cultivadas , Regulación Enzimológica de la Expresión Génica/genética , Humanos , Glicoproteínas de Membrana/genética , Ratones , Ratones Noqueados , NADP/genética , NADPH Oxidasa 2 , NADPH Oxidasa 4 , NADPH Oxidasas/genética , Neumonía Bacteriana/genética , Neumonía Bacteriana/patología , Infecciones por Pseudomonas/genética , Infecciones por Pseudomonas/patología , Especies Reactivas de Oxígeno/metabolismo
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