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1.
Mediators Inflamm ; 2019: 3481430, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31182931

RESUMEN

Macrophages (Mφ) play a central role in coordinating host response to pathogens, cellular injury, and environmental stimuli. Herein, we report multidimensional, nuclear proteomic analyses of protein expression and posttranslational modifications (PTMs) that control biological processes during Mφ activation. For this, Mφ were incubated with IFN-γ/LPS and IL-4, and their differentiation to proinflammatory (M1) and anti-inflammatory (M2a, referred as M2 for simplicity throughtout the manuscript) phenotypes was confirmed by detection of CD64 and CD206 surface markers and TNF-α, arginase I, and iNOS-dependent nitrite levels. We used a sequential method of organellar enrichment and labeling of nuclear fractions with BODIPY FL-maleimide fluorescence dye followed by two-dimensional electrophoresis (2DE) to capture quantitative changes in abundance and S-nitrosylated (SNO) proteome signatures. Exact same gels were then labeled with Pro-Q Diamond to detect protein phosphorylation. MALDI-TOF/TOF MS analysis of the protein spots with fold change of ≥|1.5| in any of the groups yielded 229 identifications. We found that 145, 78, and 173 protein spots in M1 Mφ and 105, 81, and 164 protein spots in M2 Mφ were changed in abundance, S-nitrosylation, and phosphorylation, respectively, with respect to M0 controls (fold change: ≥|1.5|, p ≤ 0.05). Targeted analysis by immunoprecipitation and Western blotting was performed to verify the differential abundance and phosphorylation levels of two of the proteins in M1 and M2 (vs. M0) Mφ. Ingenuity Pathway Analysis of the nuclear proteome datasets showed that the abundance and posttranslational (SNO and Phosphor) modifications of the proteins predicted to be involved in cytoskeletal organization/cell movement, phagocytosis/endocytosis, and cell proliferation/cell death were differentially regulated with proinflammatory and anti-inflammatory activation of Mφ.


Asunto(s)
Macrófagos/metabolismo , Animales , Western Blotting , Electroforesis en Gel Bidimensional , Citometría de Flujo , Inmunoprecipitación , Espectrometría de Masas , Ratones , Óxido Nítrico/metabolismo , Fosforilación , Análisis de Componente Principal , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
2.
Org Biomol Chem ; 9(3): 717-24, 2011 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-21082126

RESUMEN

The reactions of Z-aryl dimethyl (1), methyl phenyl (2), and diphenyl (3) phosphinates with X-anilines in dimethyl sulfoxide at 60.0 °C are studied kinetically. Kinetic results yield the primary normal deuterium kinetic isotope effects (DKIEs) involving deuterated aniline (XC(6)H(4)ND(2)) nucleophiles, k(H)/k(D) = 1.03-1.17, 1.15-1.29, and 1.24-1.51, and the cross-interaction constants (CICs), ρ(XZ) = 0.37, 0.34, and 0.65 for 1, 2, and 3, respectively. The steric effects of the ligands (R(1) and R(2)) on reaction rates play a role, but are relatively much smaller compared to other phosphinate systems. A stepwise mechanism with a rate-limiting leaving group expulsion from the intermediate is proposed on the basis of the CICs positive signs. The dominant frontside nucleophilic attack through a hydrogen-bonded, four-center-type transition state is proposed on the basis of primary normal DKIEs and large magnitudes of the CICs for 2 and 3, while both frontside and backside attack are proposed on the basis of relatively small primary normal DKIEs for 1.

3.
Clin Infect Dis ; 40(1): 46-51, 2005 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-15614691

RESUMEN

BACKGROUND: Concern about the emergence of antibiotic-resistant strains and about morbidity and/or mortality related to rheumatic fever and rheumatic heart disease has been a continuous impetus for the development of a safe, effective vaccine against group A Streptococcus (GAS). To date, >120 GAS M types are known, as identified by serological typing. In general, serum immunoglobulin G directed to the hypervariable NH2 terminal portion of M protein leads to complement fixation and opsonophagocytosis of the homologous streptococcal serotype by polymorphonuclear leukocytes, and the protection is type specific. The sequence variation at the N terminus ultimately affects the binding of opsonic antibodies. Because of hypervariability in these opsonic sequences from different M types, it was relevant to use epitopes derived from these multiple sequences in a "multivalent vaccine" design for evaluation of protection against these M types of GAS. Thus, any attempts to design vaccines for a given community will require information on N terminal-sequence typing and variation. METHODS: In the present study, we performed molecular characterization of isolates recovered from patients in northern India--to our knowledge, for the first time--in an attempt to study the circulating M types and their N terminal sequence variability. RESULTS: We report tremendous diversity in GAS strains recovered from symptomatic patients, with implications on the design of appropriate vaccines. Fifty-nine isolates represented 33 different sequence types. Very few novel types and no predominant clones were found. CONCLUSIONS: The high diversity of emm types encountered in a single year suggests that any M protein-based multivalent vaccine would have to be specifically tailored for this region.


Asunto(s)
Vacunas Bacterianas/administración & dosificación , Variación Genética , Infecciones Estreptocócicas/prevención & control , Streptococcus/clasificación , Técnicas de Tipificación Bacteriana , Genes Bacterianos , Humanos , India , Grupos de Población , Streptococcus/genética , Vacunas Sintéticas/administración & dosificación
4.
Res Microbiol ; 156(4): 575-82, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15862457

RESUMEN

The development of a group A streptococcal (GAS) vaccine has focused on the M protein, a major virulence factor. Antibodies against the amino terminal domain of the M protein are generally protective but only provide type-specific immunity. J14, a 29-mer peptide sequence which contains a conserved epitope from the C-repeat region of the M protein, offers the possibility of a vaccine which will elicit protective opsonic antibodies against multiple GAS strains. In this study we have shown that antibodies raised against J14 are capable of opsonising 37 GAS isolates representing different emm types derived from a region in which GAS infection is endemic. We also demonstrate that J14 antisera is capable of opsonising GAS isolates containing J14 homologues but not J14-specific sequences, further increasing the strain coverage of this vaccine candidate. Isolates with three C-repeats were opsonised more efficiently than isolates with two repeats. Opsonisation of a strain with only a single C-repeat was dramatically lower than other strains tested. The number of C-repeats present in the M protein of individual isolates therefore appears to be the critical factor in determining bactericidal capacity of J14 antisera. The reduced opsonic capacity of sera against this strain was shown to correlate with a reduced capacity to bind J14 antisera, as demonstrated by immunofluorescence microscopy and FACS analysis. In vivo challenge experiments also confirmed the protective efficacy of immunisation with J14 peptide.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Glicoproteínas/inmunología , Proteínas Opsoninas/inmunología , Streptococcus pyogenes/inmunología , Secuencias Repetidas Terminales , Adolescente , Secuencia de Aminoácidos , Animales , Anticuerpos Antibacterianos/sangre , Niño , Preescolar , Femenino , Variación Genética , Glicoproteínas/genética , Humanos , Sueros Inmunes/administración & dosificación , Inmunización , India/epidemiología , Ratones , Ratones Endogámicos BALB C , Datos de Secuencia Molecular , Infecciones Estreptocócicas/epidemiología , Infecciones Estreptocócicas/prevención & control , Vacunas Estreptocócicas/administración & dosificación , Vacunas Estreptocócicas/química , Streptococcus pyogenes/aislamiento & purificación
5.
PLoS Negl Trop Dis ; 8(10): e3231, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25329323

RESUMEN

BACKGROUND: Treatment of Chagas disease, caused by Trypanosoma cruzi, relies on nifurtimox and benznidazole (BZL), which present side effects in adult patients, and natural resistance in some parasite strains. Hydroxymethylnitrofurazone (NFOH) is a new drug candidate with demonstrated trypanocidal activity; however, its safety is not known. METHODS: HepG2 cells dose response to NFOH and BZL (5-100 µM) was assessed by measurement of ROS, DNA damage and survival. Swiss mice were treated with NFOH or BZL for short-term (ST, 21 d) or long-term (LT, 60 d) periods. Sera levels of cellular injury markers, liver inflammatory and oxidative stress, and fibrotic remodeling were monitored. RESULTS: HepG2 cells exhibited mild stress, evidenced by increased ROS and DNA damage, in response to NFOH, while BZL at 100 µM concentration induced >33% cell death in 24 h. In mice, NFOH ST treatment resulted in mild-to-no increase in the liver injury biomarkers (GOT, GPT), and liver levels of inflammatory (myeloperoxidase, TNF-α), oxidative (lipid peroxides) and nitrosative (3-nitrotyrosine) stress. These stress responses in NFOH LT treated mice were normalized to control levels. BZL-treated mice exhibited a >5-fold increase in GOT, GPT and TNF-α (LT) and a 20-40% increase in liver levels of MPO activity (ST and LT) in comparison with NFOH-treated mice. The liver inflammatory infiltrate was noted in the order of BZL>vehicle≥NFOH and BZL>NFOH≥vehicle, respectively, after ST and LT treatments. Liver fibrotic remodeling, identified after ST treatment, was in the order of BZL>vehicle>NFOH; lipid deposits, indicative of mitochondrial dysfunction and in the order of NFOH>vehicle>BZL were evidenced after LT treatment. CONCLUSIONS: NFOH induces mild ST hepatotoxicity that is normalized during LT treatment in mice. Our results suggest that additional studies to determine the efficacy and toxicity of NFOH are warranted.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Hígado/efectos de los fármacos , Nitrofurazona/análogos & derivados , Nitroimidazoles/efectos adversos , Tripanocidas/efectos adversos , Animales , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Enfermedad Hepática Inducida por Sustancias y Drogas , Daño del ADN/efectos de los fármacos , Femenino , Células Hep G2 , Humanos , Hígado/patología , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Nifurtimox/uso terapéutico , Nitrofurazona/efectos adversos , Nitrofurazona/uso terapéutico , Nitroimidazoles/uso terapéutico , Parásitos , Especies Reactivas de Oxígeno/metabolismo , Tripanocidas/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Factor de Necrosis Tumoral alfa , Tirosina/análogos & derivados
6.
PLoS One ; 9(11): e111539, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25372293

RESUMEN

In this study, we have utilized wild-type (WT), ASC-/-, and NLRP3-/- macrophages and inhibition approaches to investigate the mechanisms of inflammasome activation and their role in Trypanosoma cruzi infection. We also probed human macrophages and analyzed published microarray datasets from human fibroblasts, and endothelial and smooth muscle cells for T. cruzi-induced changes in the expression genes included in the RT Profiler Human Inflammasome arrays. T. cruzi infection elicited a subdued and delayed activation of inflammasome-related gene expression and IL-1ß production in mφs in comparison to LPS-treated controls. When WT and ASC-/- macrophages were treated with inhibitors of caspase-1, IL-1ß, or NADPH oxidase, we found that IL-1ß production by caspase-1/ASC inflammasome required reactive oxygen species (ROS) as a secondary signal. Moreover, IL-1ß regulated NF-κB signaling of inflammatory cytokine gene expression and, subsequently, intracellular parasite replication in macrophages. NLRP3-/- macrophages, despite an inability to elicit IL-1ß activation and inflammatory cytokine gene expression, exhibited a 4-fold decline in intracellular parasites in comparison to that noted in matched WT controls. NLRP3-/- macrophages were not refractory to T. cruzi, and instead exhibited a very high basal level of ROS (>100-fold higher than WT controls) that was maintained after infection in an IL-1ß-independent manner and contributed to efficient parasite killing. We conclude that caspase-1/ASC inflammasomes play a significant role in the activation of IL-1ß/ROS and NF-κB signaling of cytokine gene expression for T. cruzi control in human and mouse macrophages. However, NLRP3-mediated IL-1ß/NFκB activation is dispensable and compensated for by ROS-mediated control of T. cruzi replication and survival in macrophages.


Asunto(s)
Caspasa 1/metabolismo , Enfermedad de Chagas/metabolismo , Enfermedad de Chagas/parasitología , Inflamasomas/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , FN-kappa B/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Trypanosoma cruzi , Animales , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Adaptadoras de Señalización CARD , Proteínas Portadoras/genética , Enfermedad de Chagas/genética , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Humanos , Inflamasomas/genética , Macrófagos/parasitología , Ratones , Ratones Noqueados , Proteína con Dominio Pirina 3 de la Familia NLR
7.
Int J Cardiol ; 168(3): 2567-74, 2013 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-23597573

RESUMEN

BACKGROUND: The hallmark of Trypanosoma cruzi infection is cardiomyopathy that leads to end-stage heart failure. We investigated whether G-CSF, known to induce heart tissue repair by bone marrow stem cell mobilization, ameliorates T. cruzi-induced myocarditis. METHODS AND RESULTS: T. cruzi-infected C3H/He mice were treated with G-CSF and monitored for parasite burden, BMSC mobilization, cytokine profile and cardiac remodeling. G-CSF increased the expression of CXCR4, CD34, and c-Kit, indicating mobilization and migration of BMSC, some of which differentiated to cardiomyocytes as evidenced by increased levels of GATA4(+)/MEF2C(+) cells and desmin expression in chagasic hearts. G-CSF enhanced a mixed cytokine response (IL-10+TGF-ß>IFN-γ+TNF-α>IL-4) associated with increased heart inflammation and no beneficial effect on parasite control. Further, G-CSF controlled T. cruzi-induced extracellular-matrix alterations of collagens (Col I and Col llI), hydroxyproline, and glycosaminoglycan contents and promoted compensatory cardiac remodeling; however, these responses were not sufficient to control T. cruzi-induced cardiomyocyte atrophy. Benznidazole treatment prior to G-CSF resulted in the control of parasitism and parasite-induced inflammation, and subsequently, G-CSF was effective in executing the tissue repair, as evidenced by extracellular-matrix homeostasis and normalization of cardiomyocyte size in chagasic hearts. CONCLUSIONS: G-CSF treatment after T. cruzi infection enhanced migration and homing of BMSC, some of which differentiated to cardiomyocytes. Yet, G-CSF promoted a mixed (Treg>Th1>Th2) immune response that contributed to persistent inflammation and limited improvement in cardiac homeostasis. Combinatorial therapy (BZ → G-CSF) was beneficial in arresting inflammatory processes and tissue damage in chagasic hearts.


Asunto(s)
Cardiomiopatía Chagásica/tratamiento farmacológico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Animales , Diferenciación Celular , Cardiomiopatía Chagásica/inmunología , Femenino , Movilización de Célula Madre Hematopoyética , Masculino , Ratones , Ratones Endogámicos C3H , Miocitos Cardíacos/citología , Inducción de Remisión
8.
Virology ; 418(2): 93-101, 2011 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-21835421

RESUMEN

Respiratory syncytial virus (RSV) is the most common cause of epidemic respiratory diseases in infants and young children. RSV infection of airway epithelial cells induces the expression of immune/inflammatory genes through the activation of a subset of transcription factors, including Nuclear Factor-κB (NF-κB) and AP-1. In this study, we have investigated the signaling pathway leading to activation of these two transcription factors in response to RSV infection. Our results show that IKKß plays a key role in viral-induced NF-κB activation, while JNK regulates AP-1-dependent gene transcription, as demonstrated by using kinase inactive proteins and chemical inhibitors of the two kinases. Inhibition of TAK1 activation, by overexpression of kinase inactive TAK1 or using cells lacking TAK1 expression, significantly reduced RSV-induced NF-κB and AP-1 nuclear translocation and DNA-binding activity, as well as NF-κB-dependent gene expression, identifying TAK1 as an important upstream signaling molecule regulating RSV-induced NF-κB and AP-1 activation.


Asunto(s)
Células Epiteliales/metabolismo , Quinasas Quinasa Quinasa PAM/metabolismo , FN-kappa B/metabolismo , Virus Sincitiales Respiratorios/fisiología , Factor de Transcripción AP-1/metabolismo , Línea Celular , Células Epiteliales/virología , Regulación de la Expresión Génica , Humanos , Quinasa I-kappa B/genética , Quinasa I-kappa B/metabolismo , Quinasas Quinasa Quinasa PAM/genética , Mutación , Mucosa Respiratoria/citología , Factor de Transcripción AP-1/genética
9.
Diabetes ; 60(7): 1907-16, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21593200

RESUMEN

OBJECTIVE: Klotho is an antiaging hormone present in the kidney that extends the lifespan, regulates kidney function, and modulates cellular responses to oxidative stress. We investigated whether Klotho levels and signaling modulate inflammation in diabetic kidneys. RESEARCH DESIGN AND METHODS: Renal Klotho expression was determined by quantitative real-time PCR and immunoblot analysis. Primary mouse tubular epithelial cells were treated with methylglyoxalated albumin, and Klotho expression and inflammatory cytokines were measured. Nuclear factor (NF)-κB activation was assessed by treating human embryonic kidney (HEK) 293 and HK-2 cells with tumor necrosis factor (TNF)-α in the presence or absence of Klotho, followed by immunoblot analysis to evaluate inhibitor of κB (IκB)α degradation, IκB kinase (IKK) and p38 activation, RelA nuclear translocation, and phosphorylation. A chromatin immunoprecipitation assay was performed to analyze the effects of Klotho signaling on interleukin-8 and monocyte chemoattractant protein-1 promoter recruitment of RelA and RelA serine (Ser)(536). RESULTS: Renal Klotho mRNA and protein were significantly decreased in db/db mice, and a similar decline was observed in the primary cultures of mouse tubule epithelial cells treated with methylglyoxal-modified albumin. The exogenous addition of soluble Klotho or overexpression of membranous Klotho in tissue culture suppressed NF-κB activation and subsequent production of inflammatory cytokines in response to TNF-α stimulation. Klotho specifically inhibited RelA Ser(536) phosphorylation as well as promoter DNA binding of this phosphorylated form of RelA without affecting IKK-mediated IκBα degradation, total RelA nuclear translocation, and total RelA DNA binding. CONCLUSIONS: These findings suggest that Klotho serves as an anti-inflammatory modulator, negatively regulating the production of NF-κB-linked inflammatory proteins via a mechanism that involves phosphorylation of Ser(536) in the transactivation domain of RelA.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Nefropatías Diabéticas/patología , Glucuronidasa/fisiología , Inflamación/patología , Riñón/patología , Transducción de Señal/fisiología , Animales , Células Cultivadas , Citocinas/biosíntesis , Glucuronidasa/genética , Células HEK293 , Humanos , Túbulos Renales/metabolismo , Proteínas Klotho , Masculino , Ratones , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Estrés Oxidativo/efectos de los fármacos , Factor de Transcripción ReIA/metabolismo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
10.
PLoS One ; 5(6): e11095, 2010 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-20559430

RESUMEN

BACKGROUND: Numerous metabolic pathways have been implicated in diabetes-induced renal injury, yet few studies have utilized unbiased systems biology approaches for mapping the interconnectivity of diabetes-dysregulated proteins that are involved. We utilized a global, quantitative, differential proteomic approach to identify a novel retinoic acid hub in renal cortical protein networks dysregulated by type 2 diabetes. METHODOLOGY/PRINCIPAL FINDINGS: Total proteins were extracted from renal cortex of control and db/db mice at 20 weeks of age (after 12 weeks of hyperglycemia in the diabetic mice). Following trypsinization, (18)O- and (16)O-labeled control and diabetic peptides, respectively, were pooled and separated by two dimensional liquid chromatography (strong cation exchange creating 60 fractions further separated by nano-HPLC), followed by peptide identification and quantification using mass spectrometry. Proteomic analysis identified 53 proteins with fold change >or=1.5 and p

Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Riñón/metabolismo , Espectrometría de Masas/métodos , Tretinoina/metabolismo , Animales , Western Blotting , Cromatografía Líquida de Alta Presión/métodos , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Isótopos de Oxígeno , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Org Biomol Chem ; 5(24): 3944-50, 2007 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-18043798

RESUMEN

The reactions of ethyl Y-phenyl chloro (1) and chlorothio (2) phosphates with X-anilines in acetonitrile at 55.0 degrees C are studied kinetically and theoretically. Kinetic results yield the primary kinetic isotope effects (k(H)/k(D) = 1.07-1.80 and 1.06-1.27 for 1 and 2, respectively) with deuterated aniline (XC(6)H(4)ND(2)) nucleophiles, and the cross-interaction constants rho(XY) = -0.60 and -0.28 for and , respectively. A concerted mechanism involving a partial frontside attack through a hydrogen-bonded, four-center-type transition state is proposed. The large rho(X) (rho(nuc) = -3.1 to -3.4) and beta(X) (beta(nuc) = 1.1-1.2) values seem to be characteristic of the anilinolysis of phosphates and thiophosphates with the Cl leaving group. Because of the relatively large size of the aniline nucleophile, the degree of steric hindrance could be the decisive factor that determines the direction of the nucleophilic attack to the phosphate and thiophosphate substrates with the relatively small-sized Cl leaving group.


Asunto(s)
Aminas/química , Compuestos de Anilina/química , Fosfatos/química , Catálisis , Hidrólisis , Cinética , Modelos Químicos , Estructura Molecular
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