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1.
Proc Natl Acad Sci U S A ; 120(28): e2301115120, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37399418

RESUMEN

Enteric bacterial pathogens pose significant threats to human health; however, the mechanisms by which they infect the mammalian gut in the face of daunting host defenses and an established microbiota remain poorly defined. For the attaching and effacing (A/E) bacterial family member and murine pathogen Citrobacter rodentium, its virulence strategy likely involves metabolic adaptation to the host's intestinal luminal environment, as a necessary precursor to reach and infect the mucosal surface. Suspecting this adaptation involved the intestinal mucus layer, we found that C. rodentium was able to catabolize sialic acid, a monosaccharide derived from mucins, and utilize it as its sole carbon source for growth. Moreover, C. rodentium also sensed and displayed chemotactic activity toward sialic acid. These activities were abolished when the nanT gene, encoding a sialic acid transporter, was deleted (ΔnanT). Correspondingly, the ΔnanT C. rodentium strain was significantly impaired in its ability to colonize the murine intestine. Intriguingly, sialic acid was also found to induce the secretion of two autotransporter proteins, Pic and EspC, which possess mucinolytic and host-adherent properties. As a result, sialic acid enhanced the ability of C. rodentium to degrade intestinal mucus (through Pic), as well as to adhere to intestinal epithelial cells (through EspC). We thus demonstrate that sialic acid, a monosaccharide constituent of the intestinal mucus layer, functions as an important nutrient and a key signal for an A/E bacterial pathogen to escape the colonic lumen and directly infect its host's intestinal mucosa.


Asunto(s)
Citrobacter rodentium , Infecciones por Enterobacteriaceae , Animales , Ratones , Bacterias , Citrobacter , Infecciones por Enterobacteriaceae/microbiología , Mucosa Intestinal/microbiología , Mamíferos , Monosacáridos , Ácido N-Acetilneuramínico
2.
Cell Mol Life Sci ; 80(2): 50, 2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36694058

RESUMEN

The transdifferentiation from cardiac fibroblasts to myofibroblasts is an important event in the initiation of cardiac fibrosis. However, the underlying mechanism is not fully understood. Circ-sh3rf3 (circular RNA SH3 domain containing Ring Finger 3) is a novel circular RNA which was induced in hypertrophied ventricles by isoproterenol hydrochloride, and our work has established that it is a potential regulator in cardiac hypertrophy, but whether circ-sh3rf3 plays a role in cardiac fibrosis remains unclear, especially in the conversion of cardiac fibroblasts into myofibroblasts. Here, we found that circ-sh3rf3 was down-regulated in isoproterenol-treated rat cardiac fibroblasts and cardiomyocytes as well as during fibroblast differentiation into myofibroblasts. We further confirmed that circ-sh3rf3 could interact with GATA-4 proteins and reduce the expression of GATA-4, which in turn abolishes GATA-4 repression of miR-29a expression and thus up-regulates miR-29a expression, thereby inhibiting fibroblast-myofibroblast differentiation and myocardial fibrosis. Our work has established a novel Circ-sh3rf3/GATA-4/miR-29a regulatory cascade in fibroblast-myofibroblast differentiation and myocardial fibrosis, which provides a new therapeutic target for myocardial fibrosis.


Asunto(s)
Cardiomiopatías , Fibroblastos , Fibrosis , Miofibroblastos , ARN Circular , Animales , Ratas , Cardiomiopatías/genética , Cardiomiopatías/metabolismo , Cardiomiopatías/patología , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Fibroblastos/metabolismo , Fibrosis/genética , Fibrosis/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Miocitos Cardíacos/metabolismo , Miofibroblastos/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34625492

RESUMEN

Group 3 innate lymphoid cells (ILC3s) control the formation of intestinal lymphoid tissues and play key roles in intestinal defense. They express neuropeptide vasoactive intestinal peptide (VIP) receptor 2 (VPAC2), through which VIP modulates their function, but whether VIP exerts other effects on ILC3 remains unclear. We show that VIP promotes ILC3 recruitment to the intestine through VPAC1 independent of the microbiota or adaptive immunity. VIP is also required for postnatal formation of lymphoid tissues as well as the maintenance of local populations of retinoic acid (RA)-producing dendritic cells, with RA up-regulating gut-homing receptor CCR9 expression by ILC3s. Correspondingly, mice deficient in VIP or VPAC1 suffer a paucity of intestinal ILC3s along with impaired production of the cytokine IL-22, rendering them highly susceptible to the enteric pathogen Citrobacter rodentium This heightened susceptibility to C. rodentium infection was ameliorated by RA supplementation, adoptive transfer of ILC3s, or by recombinant IL-22. Thus, VIP regulates the recruitment of intestinal ILC3s and formation of postnatal intestinal lymphoid tissues, offering protection against enteric pathogens.


Asunto(s)
Citrobacter rodentium/inmunología , Infecciones por Enterobacteriaceae/inmunología , Linfocitos/inmunología , Receptores de Tipo II del Péptido Intestinal Vasoactivo/metabolismo , Péptido Intestinal Vasoactivo/metabolismo , Animales , Células Dendríticas/inmunología , Microbioma Gastrointestinal/inmunología , Interleucinas/análisis , Tejido Linfoide/citología , Tejido Linfoide/crecimiento & desarrollo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores CCR/biosíntesis , Receptores de Tipo II del Péptido Intestinal Vasoactivo/genética , Tretinoina/metabolismo , Péptido Intestinal Vasoactivo/genética , Interleucina-22
4.
J Pediatr Nurs ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38523049

RESUMEN

PROBLEM: The phenomenon of emergence delirium in pediatric patients undergoing general anesthesia has garnered increasing attention in the academic community. While formal non-pharmaceutical interventions have demonstrated efficacy in mitigating this phenomenon, the diversity of intervention types and their varying degrees of effectiveness necessitate further discussion. A scoping review was conducted to identify and explicate the categorization, content elements, and outcomes measures of non-pharmacological interventions utilized to forestall the onset of emergence delirium in children undergoing general anesthesia. ELIGIBILITY CRITERIA: This review was conducted in accordance with the Arksey and O'Malley's methodology framework and PRISMA-ScR. It encompassed experimental and quasi-experimental studies that involved any non-pharmacological interventions during the perioperative period to prevent emergence delirium in children aged 0 to 18 years undergoing general anesthesia for elective surgery. SAMPLE: Thirty-two articles met the inclusion criteria, of which 29 were randomized controlled trials. The total sample size of the population was 4633. RESULTS: The scoping review revealed 10 non-pharmacological interventions, that included distraction intervention, visual preconditioning, virtual reality, parental participation, maternal voice, light drinking, acupuncture, auditory stimulation, monochromic light and breathing training. Emergence delirium, preoperative anxiety, and postoperative pain were the primary outcomes, and four assessment instruments were employed to measure the extent and incidence of emergence delirium. CONCLUSION: Numerous non-pharmacological interventions have been employed to prevent emergence delirium. Nevertheless, the effectiveness of some interventions is not yet evident. IMPLICATIONS: The utilization of visual preconditioning and distraction interventions appears to be an emerging area of interest.

5.
BMC Plant Biol ; 23(1): 310, 2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-37296391

RESUMEN

BACKGROUND: Abscisic acid (ABA) receptor pyrabactin resistance 1/PYR1-like/regulatory components of ABA receptor proteins (PYR/PYL/RCARs) have been demonstrated to play pivotal roles in ABA signaling and in response to diverse environmental stimuli including drought, salinity and osmotic stress in Arabidopsis. However, whether and how GhPYL9-5D and GhPYR1-3A, the homologues of Arabidopsis PYL9 and PYR1 in cotton, function in responding to ABA and abiotic stresses are still unclear. RESULTS: GhPYL9-5D and GhPYR1-3A were targeted to the cytoplasm and nucleus. Overexpression of GhPYL9-5D and GhPYR1-3A in Arabidopsis wild type and sextuple mutant pyr1pyl1pyl2pyl4pyl5pyl8 plants resulted in ABA hypersensitivity in terms of seed germination, root growth and stomatal closure, as well as seedling tolerance to water deficit, salt and osmotic stress. Moreover, the VIGS (Virus-induced gene silencing) cotton plants, in which GhPYL9-5D or GhPYR1-3A were knocked down, showed clearly reduced tolerance to polyethylene glycol 6000 (PEG)-induced drought, salinity and osmotic stresses compared with the controls. Additionally, transcriptomic data revealed that GhPYL9-5D was highly expressed in the root, and GhPYR1-3A was strongly expressed in the fiber and stem. GhPYL9-5D, GhPYR1-3A and their homologs in cotton were highly expressed after treatment with PEG or NaCl, and the two genes were co-expressed with redox signaling components, transcription factors and auxin signal components. These results suggest that GhPYL9-5D and GhPYR1-3A may serve important roles through interplaying with hormone and other signaling components in cotton adaptation to salt or osmotic stress. CONCLUSIONS: GhPYL9-5D and GhPYR1-3A positively regulate ABA-mediated seed germination, primary root growth and stomatal closure, as well as tolerance to drought, salt and osmotic stresses likely through affecting the expression of multiple downstream stress-associated genes in Arabidopsis and cotton.


Asunto(s)
Arabidopsis , Arabidopsis/metabolismo , Ácido Abscísico/farmacología , Ácido Abscísico/metabolismo , Presión Osmótica , Gossypium/genética , Gossypium/metabolismo , Sequías , Salinidad , Plantas Modificadas Genéticamente/genética , Estrés Fisiológico/genética , Cloruro de Sodio/metabolismo , Proteínas Portadoras/genética , Regulación de la Expresión Génica de las Plantas , Germinación/genética
6.
Int J Mol Sci ; 24(20)2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37895102

RESUMEN

The original 'Green Revolution' genes are associated with gibberellin deficiency. However, in some species, mutations in these genes cause pleiotropic phenotypes, preventing their application in dwarf breeding. The development of novel genotypes with reduced plant height will resolve this problem. In a previous study, we obtained two dwarf lines, L28 and L30, by introducing the Ammopiptanthus mongolicus (Maxim. ex Kom.) Cheng f. C-repeat-binding factor 1 (AmCBF1) into the upland cotton variety R15. We found that Gossypium hirsutum Tubulin beta-1 (GhTUBB1) was downregulated in L28 and L30, which suggested that this gene may have contributed to the dwarf phenotype of L28 and L30. Here, we tested this hypothesis by silencing GhTUBB1 expression in R15 and found that decreased expression resulted in a dwarf phenotype. Interestingly, we found that repressing AmCBF1 expression in L28 and L30 partly recovered the expression of GhTUBB1. Thus, AmCBF1 expression presented a negative relationship with GhTUBB1 expression in L28 and L30. Moreover, yeast one-hybrid and dual-luciferase assays suggest that AmCBF1 negatively regulates GhTUBB1 expression by directly binding to C-repeat/dehydration-responsive (CRT/DRE) elements in the GhTUBB1 promoter, potentially explaining the dwarf phenotypes of L28 and L30. This study elucidates the regulation of GhTUBB1 expression by AmCBF1 and suggests that GhTUBB1 may be a new target gene for breeding dwarf and compact cultivars.


Asunto(s)
Gossypium , Tubulina (Proteína) , Gossypium/metabolismo , Tubulina (Proteína)/metabolismo , Fitomejoramiento , Fenotipo , Genotipo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
7.
J Immunol ; 205(2): 329-334, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32540993

RESUMEN

A layer of mucus functions to segregate contents of the intestinal lumen from the intestinal epithelium. The MUC2 mucin is the primary constituent of intestinal mucus and plays critical protective roles against luminal microbes and other noxious agents. In this study, we investigated whether MUC2 helps maintain CD8 T cell tolerance toward intestinal luminal Ags by gavaging wild-type and Muc2-/- mice with a model Ag and monitoring immune responses posttreatment. We report that orally delivered OVA rapidly disseminates through the blood of Muc2-/- (but not control) mice and causes immune activation of Ag-specific CD8 T cells at both local and distal sites. Further, the administration of oral OVA to Muc2-/- mice led to its presentation by thymic dendritic cells and the deletion of Ag-specific thymocytes. Collectively, our findings suggest that intestinal mucus helps limit the shaping of the TCR repertoire of developing thymocytes by intestinal luminal Ags.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Intestinos/fisiología , Mucina 2/metabolismo , Moco/metabolismo , Administración Oral , Animales , Antígenos/inmunología , Diferenciación Celular , Proliferación Celular , Supresión Clonal , Tolerancia Inmunológica , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mucina 2/genética
8.
J Integr Plant Biol ; 64(4): 836-842, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35238484

RESUMEN

Verticillium wilt caused by Verticillium dahliae is a major disease of cotton. Acidic protein-lipopolysaccharide complexes are thought to be the toxins responsible for its symptoms. Here, we determined that the sphingolipid biosynthesis inhibitor fumonisin B1 (FB1) acts as a toxin and phenocopies the symptoms induced by V. dahliae. Knocking out genes required for FB1 biosynthesis reduced V. dahliae pathogenicity. Moreover, we showed that overexpression of a FB1 and V. dahliae both downregulated gene, GhIQD10, enhanced verticillium wilt resistance by promoting the expression of brassinosteroid and anti-pathogen genes. Our results provide a new strategy for preventing verticillium wilt in cotton.


Asunto(s)
Verticillium , Resistencia a la Enfermedad/genética , Fumonisinas , Regulación de la Expresión Génica de las Plantas , Gossypium/genética , Enfermedades de las Plantas/genética , Esfingolípidos/metabolismo
9.
Int J Mol Sci ; 22(21)2021 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-34768870

RESUMEN

Cotton fiber is a seed trichome that protrudes from the outer epidermis of cotton ovule on the day of anthesis (0 day past anthesis, 0 DPA). The initial number and timing of fiber cells are closely related to fiber yield and quality. However, the mechanism underlying fiber initiation is still unclear. Here, we detected and compared the contents and compositions of sphingolipids and sterols in 0 DPA ovules of Xuzhou142 lintless-fuzzless mutants (Xufl) and Xinxiangxiaoji lintless-fuzzless mutants (Xinfl) and upland cotton wild-type Xuzhou142 (XuFL). Nine classes of sphingolipids and sixty-six sphingolipid molecular species were detected in wild-type and mutants. Compared with the wild type, the contents of Sphingosine-1-phosphate (S1P), Sphingosine (Sph), Glucosylceramide (GluCer), and Glycosyl-inositol-phospho-ceramides (GIPC) were decreased in the mutants, while the contents of Ceramide (Cer) were increased. Detail, the contents of two Cer molecular species, d18:1/22:0 and d18:1/24:0, and two Phyto-Cer molecular species, t18:0/22:0 and t18:0/h22:1 were significantly increased, while the contents of all GluCer and GIPC molecular species were decreased. Consistent with this result, the expression levels of seven genes involved in GluCer and GIPC synthesis were decreased in the mutants. Furthermore, exogenous application of a specific inhibitor of GluCer synthase, PDMP (1-phenyl-2-decanoylamino-3-morpholino-1-propanol), in ovule culture system, significantly inhibited the initiation of cotton fiber cells. In addition, five sterols and four sterol esters were detected in wild-type and mutant ovules. Compared with the wild type, the contents of total sterol were not significantly changed. While the contents of stigmasterol and campesterol were significantly increased, the contents of cholesterol were significantly decreased, and the contents of total sterol esters were significantly increased. In particular, the contents of campesterol esters and stigmasterol esters increased significantly in the two mutants. Consistently, the expression levels of some sterol synthase genes and sterol ester synthase genes were also changed in the two mutants. These results suggested that sphingolipids and sterols might have some roles in the initiation of fiber cells. Our results provided a novel insight into the regulatory mechanism of fiber cell initiation.


Asunto(s)
Gossypium/metabolismo , Fitosteroles/metabolismo , Esfingolípidos/metabolismo , Metabolismo de los Hidratos de Carbono/genética , Fibra de Algodón/análisis , Expresión Génica/genética , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica de las Plantas/genética , Genes de Plantas/genética , Metabolómica/métodos , Óvulo Vegetal/genética , Proteínas de Plantas/genética , Esteroles/metabolismo , Transcriptoma/genética
10.
Water Sci Technol ; 80(1): 109-116, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31461427

RESUMEN

Due to the high Brunauer-Emmett-Teller (BET) surface area of zeolitic imidazolate framework (ZIF)-8, a secondary crystallization method was used to prepare a particle electrode of γ-Al2O3@ZIF-8. According to the results from a field emission scanning electron microscope (SEM) and X-ray diffractometer (XRD), the particle electrode of γ-Al2O3 was successfully loaded with ZIF-8, and the BET surface area (1,433 m2/g) of ZIF-8 was over ten times that of γ-Al2O3. The key operation parameters of cell voltage, pH, initial RhB concentration and electrolyte concentration were all optimized. The observed rate constant (kobs) of the pseudo-first-order kinetic model for the electrocatalytic oxidation (ECO) system with the particle electrode of γ-Al2O3@ZIF-8 (15.2 × 10-2 min-1) was over five times higher than that of the system with the traditional particle electrode of γ-Al2O3 (2.6 × 10-2 min-1). The loading of ZIF-8 on the surface of γ-Al2O3 played an important role in improving electrocatalytic activity for the degradation of Rhodamine B (RhB), and the RhB removal efficiency of the three-dimensional (3D) electrocatalytic system with the particle electrode of γ-Al2O3@ZIF-8 was 93.5% in 15 min, compared with 27.5% in 15 min for the particle electrode of γ-Al2O3. The RhB removal efficiency was kept over 85% after five cycles of reuse for the 3D electrocatalytic system with the particle electrode of γ-Al2O3@ZIF-8.


Asunto(s)
Electrodos , Rodaminas/química , Zeolitas , Oxidación-Reducción , Rodaminas/análisis , Eliminación de Residuos Líquidos
11.
PLoS Pathog ; 11(8): e1005107, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26295949

RESUMEN

Efficient acquisition of extracellular nutrients is essential for bacterial pathogenesis, however the identities and mechanisms for transport of many of these substrates remain unclear. Here, we investigate the predicted iron-binding transporter AfuABC and its role in bacterial pathogenesis in vivo. By crystallographic, biophysical and in vivo approaches, we show that AfuABC is in fact a cyclic hexose/heptose-phosphate transporter with high selectivity and specificity for a set of ubiquitous metabolites (glucose-6-phosphate, fructose-6-phosphate and sedoheptulose-7-phosphate). AfuABC is conserved across a wide range of bacterial genera, including the enteric pathogens EHEC O157:H7 and its murine-specific relative Citrobacter rodentium, where it lies adjacent to genes implicated in sugar sensing and acquisition. C. rodentium ΔafuA was significantly impaired in an in vivo murine competitive assay as well as its ability to transmit infection from an afflicted to a naïve murine host. Sugar-phosphates were present in normal and infected intestinal mucus and stool samples, indicating that these metabolites are available within the intestinal lumen for enteric bacteria to import during infection. Our study shows that AfuABC-dependent uptake of sugar-phosphates plays a critical role during enteric bacterial infection and uncovers previously unrecognized roles for these metabolites as important contributors to successful pathogenesis.


Asunto(s)
Metabolismo de los Hidratos de Carbono/fisiología , Infecciones por Enterobacteriaceae/metabolismo , Infecciones por Enterobacteriaceae/transmisión , Intestinos/microbiología , Animales , Transporte Biológico Activo/fisiología , Calorimetría , Cromatografía Liquida , Citrobacter rodentium , Mucosa Intestinal/metabolismo , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Mutagénesis Sitio-Dirigida , Fosforilación , Filogenia , Espectrometría de Masas en Tándem
12.
PLoS Pathog ; 11(8): e1005108, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26285214

RESUMEN

Enterohemorrhagic Escherichia coli and related food and waterborne pathogens pose significant threats to human health. These attaching/effacing microbes infect the apical surface of intestinal epithelial cells (IEC), causing severe diarrheal disease. Colonizing the intestinal luminal surface helps segregate these microbes from most host inflammatory responses. Based on studies using Citrobacter rodentium, a related mouse pathogen, we speculate that hosts rely on immune-mediated changes in IEC, including goblet cells to defend against these pathogens. These changes include a CD4+ T cell-dependent increase in IEC proliferation to replace infected IEC, as well as altered production of the goblet cell-derived mucin Muc2. Another goblet cell mediator, REsistin-Like Molecule (RELM)-ß is strongly induced within goblet cells during C. rodentium infection, and was detected in the stool as well as serum. Despite its dramatic induction, RELM-ß's role in host defense is unclear. Thus, wildtype and RELM-ß gene deficient mice (Retnlb-/-) were orally infected with C. rodentium. While their C. rodentium burdens were only modestly elevated, infected Retnlb-/- mice suffered increased mortality and mucosal ulceration due to deep pathogen penetration of colonic crypts. Immunostaining for Ki67 and BrDU revealed Retnlb-/- mice were significantly impaired in infection-induced IEC hyper-proliferation. Interestingly, exposure to RELM-ß did not directly increase IEC proliferation, rather RELM-ß acted as a CD4+ T cell chemoattractant. Correspondingly, Retnlb-/- mice showed impaired CD4+ T cell recruitment to their infected colons, along with reduced production of interleukin (IL)-22, a multifunctional cytokine that directly increased IEC proliferation. Enema delivery of RELM-ß to Retnlb-/- mice restored CD4+ T cell recruitment, concurrently increasing IL-22 levels and IEC proliferation, while reducing mucosal pathology. These findings demonstrate that RELM-ß and goblet cells play an unexpected, yet critical role in recruiting CD4+ T cells to the colon to protect against an enteric pathogen, in part via the induction of increased IEC proliferation.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Proliferación Celular , Colitis/inmunología , Células Caliciformes/inmunología , Hormonas Ectópicas/inmunología , Mucosa Intestinal/inmunología , Animales , Separación Celular , Citrobacter rodentium , Colitis/metabolismo , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Células Caliciformes/metabolismo , Hormonas Ectópicas/metabolismo , Péptidos y Proteínas de Señalización Intercelular , Mucosa Intestinal/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Reacción en Cadena de la Polimerasa
13.
J Immunol ; 193(12): 5841-53, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25362182

RESUMEN

IL-17 plays critical roles in host defenses, combating bacterial and fungal infections, as well as the pathogenesis of autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE). The signaling adaptor SAP is essential for normal immune homeostasis and mutations within SH2D1A, the locus encoding this protein, result in serious and sometimes fatal syndromes, including X-linked lymphoproliferative disease and severe cases of common variable immunodeficiency. However, the precise cellular basis of how SAP deficiency contributes to immune dysfunction remains incompletely understood. In this study, we found that CD4 and CD8 T cells lacking SAP had a diminished capacity to differentiate into IL-17-producing Th17 and T cytotoxic (Tc17) cells relative to wild-type lymphocytes. The use of costimulating SLAM Abs was found to augment the differentiation of IL-17-secreting effectors in wild-type but not Sh2d1a(-/-) splenic T cells under IL-17-polarizing conditions. In addition, SAP's regulation of IL-17-secreting T cells was shown to be a T cell-intrinsic role, as purified naive Sh2d1a(-/-) CD4 and CD8 T cells were inherently defective at converting into Th17 and Tc17 cells in vitro and in vivo. Furthermore, Sh2d1a(-/-) mice were protected from EAE and exhibited greatly decreased numbers of CNS-infiltrating Th17 and Tc17 effector T cells and reduced disease severity. Collectively, these results suggest that SLAM-SAP signaling drives the differentiation and function of Th17 and Tc17 cells in vitro and in vivo and contributes to the pathogenesis of autoimmunity in EAE.


Asunto(s)
Antígenos CD/metabolismo , Encefalomielitis Autoinmune Experimental/inmunología , Encefalomielitis Autoinmune Experimental/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Receptores de Superficie Celular/metabolismo , Transducción de Señal , Células Th17/inmunología , Células Th17/metabolismo , Animales , Antígenos CD/genética , Diferenciación Celular , Progresión de la Enfermedad , Encefalomielitis Autoinmune Experimental/genética , Expresión Génica , Inmunización , Inmunofenotipificación , Interferón gamma/metabolismo , Interleucina-17/biosíntesis , Interleucina-4/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Ratones , Ratones Noqueados , Glicoproteína Mielina-Oligodendrócito/inmunología , Fenotipo , Receptores de Superficie Celular/genética , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria , Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Subgrupos de Linfocitos T/citología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Células Th17/citología
14.
Cell Mol Life Sci ; 72(10): 2005-22, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25504289

RESUMEN

The regulation of cardiac differentiation is critical for maintaining normal cardiac development and function. The precise mechanisms whereby cardiac differentiation is regulated remain uncertain. Here, we have identified a GATA-4 target, EGF, which is essential for cardiogenesis and regulates cardiac differentiation in a dose- and time-dependent manner. Moreover, EGF demonstrates functional interaction with GATA-4 in inducing the cardiac differentiation of P19CL6 cells in a time- and dose-dependent manner. Biochemically, GATA-4 forms a complex with STAT3 to bind to the EGF promoter in response to EGF stimulation and cooperatively activate the EGF promoter. Functionally, the cooperation during EGF activation results in the subsequent activation of cyclin D1 expression, which partly accounts for the lack of additional induction of cardiac differentiation by the GATA-4/STAT3 complex. Thus, we propose a model in which the regulatory cascade of cardiac differentiation involves GATA-4, EGF, and cyclin D1.


Asunto(s)
Diferenciación Celular/fisiología , Factor de Crecimiento Epidérmico/metabolismo , Factor de Transcripción GATA4/metabolismo , Corazón/embriología , Modelos Biológicos , Miocardio/citología , Transducción de Señal/fisiología , Animales , Western Blotting , Línea Celular Tumoral , Inmunoprecipitación de Cromatina , Técnicas Histológicas , Inmunoprecipitación , Ratones , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Tiempo
15.
Water Sci Technol ; 73(7): 1709-18, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27054744

RESUMEN

Initially, porous acrylonitrile/itaconic acid copolymers (AN/IA) were prepared by suspended emulsion polymerization. Successively, the cyano groups in AN/IA copolymers were converted to amidoxime (AO) groups by the reaction with hydroxylamine hydrochloride. The structures of the AN/IA and amidoximated AN/IA (AO AN/IA) were characterized by infrared spectroscopy, scanning electron microscopy, and porous structural analysis. The adsorption properties of AO AN/IA for Hg(II) were investigated. The results show that AO AN/IA has mesopores and macropores, and surface area of 11.71 m(2) g(-1). It was found that AO AN/IA has higher affinity for Hg(II), with the maximum adsorption capacity of 84.25 mg g(-1). The AO AN/IA also can effectively remove Hg(II) from different binary metal ion mixture systems. Furthermore, the adsorption kinetics and thermodynamics were studied in detail. The adsorption equilibrium can quickly be achieved in 4 h determined by an adsorption kinetics study. The adsorption process is found to belong to the second-order model, and can be described by the Freundlich model.


Asunto(s)
Acrilonitrilo/química , Mercurio/química , Polímeros/química , Adsorción , Emulsiones , Concentración de Iones de Hidrógeno , Cinética , Metales/química , Microscopía Electrónica de Rastreo , Polimerizacion , Porosidad , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica
16.
J Cell Biochem ; 116(8): 1755-65, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25736800

RESUMEN

It has been reported that the antitumor drug doxorubicin (Dox) exerts its toxic effects via GATA-4 depletion and that over-expression of GATA-4 reverses Dox-induced toxicity and apoptosis; however, the precise mechanisms remain unclear. In this study, we observed, for the first time, that EGF protects cells against Dox-mediated growth arrest, G2/M-phase arrest, and apoptosis. Additionally, EGF expression was down-regulated in Dox-treated cells and up-regulated in GATA-4 over-expressing cells. Utilizing real-time PCR and western blotting analysis, we found that the expression of the cell cycle-associated protein cyclin D1 was inhibited in GATA-4-silenced cells and Dox-treated cells and was enhanced in GATA-4 over-expressing cells and EGF-treated cells. Furthermore, EGF treatment reversed the inhibited expression of cyclin D1 that was mediated by GATA-4 RNAi or Dox. Our results indicate that EGF, as a downstream target of Dox, may be involved in Dox-induced toxicity as well as in the protective role of GATA-4 against toxicity induced by Dox via regulating cyclin D1 expression, which elucidates a new molecular mechanism of Dox toxicity with important clinical implications.


Asunto(s)
Antibióticos Antineoplásicos/farmacología , Ciclina D1/metabolismo , Doxorrubicina/farmacología , Factor de Crecimiento Epidérmico/farmacología , Factor de Transcripción GATA4/metabolismo , Animales , Apoptosis , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Factor de Transcripción GATA4/genética , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Ratones
17.
Am J Physiol Gastrointest Liver Physiol ; 309(9): G730-42, 2015 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-26336925

RESUMEN

Vitamin D deficiency affects more that 1 billion people worldwide. Although thought to increase risk of bacterial infections, the importance of vitamin D on host defense against intestinal bacterial pathogens is currently unclear since injection of the active form of vitamin D, 1,25(OH)2D3, increased susceptibility to the enteric bacterial pathogen Citrobacter rodentium by suppressing key immune/inflammatory factors. To further characterize the role of vitamin D during bacteria-induced colitis, we fed weanling mice either vitamin D3-deficient or vitamin D3-sufficient diets for 5 wk and then challenged them with C. rodentium. Vitamin D3-deficient mice lost significantly more body weight, carried higher C. rodentium burdens, and developed worsened histological damage. Vitamin D3-deficient mice also suffered greater bacterial translocation to extra-intestinal tissues, including mesenteric lymph nodes, spleen, and liver. Intestinal tissues of infected vitamin D3-deficient mice displayed increased inflammatory cell infiltrates as well as significantly higher gene transcript levels of inflammatory mediators TNF-α, IL-1ß, IL-6, TGF-ß, IL-17A, and IL-17F as well as the antimicrobial peptide REG3γ. Notably, these exaggerated inflammatory responses accelerated the loss of commensal microbes and were associated with an impaired ability to detoxify bacterial lipopolysaccharide. Overall, these studies show that dietary-induced vitamin D deficiency exacerbates intestinal inflammatory responses to infection, also impairing host defense.


Asunto(s)
Traslocación Bacteriana , Colecalciferol/deficiencia , Citrobacter rodentium/patogenicidad , Colitis/microbiología , Colon/microbiología , Dieta , Infecciones por Enterobacteriaceae/microbiología , Mucosa Intestinal/microbiología , Deficiencia de Vitamina D/complicaciones , Animales , Carga Bacteriana , Ciego/inmunología , Ciego/metabolismo , Ciego/microbiología , Colitis/inmunología , Colitis/metabolismo , Colitis/patología , Colon/inmunología , Colon/metabolismo , Colon/patología , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Infecciones por Enterobacteriaceae/complicaciones , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/metabolismo , Heces/microbiología , Femenino , Interacciones Huésped-Patógeno , Mediadores de Inflamación/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Receptores de Lipopolisacáridos/sangre , Lipopolisacáridos/metabolismo , Ratones Endogámicos C57BL , Proteínas Asociadas a Pancreatitis , Fosforilación , Proteínas/genética , Proteínas/metabolismo , Factores de Tiempo , Deficiencia de Vitamina D/inmunología , Deficiencia de Vitamina D/metabolismo , Pérdida de Peso
18.
Mol Cell Probes ; 29(3): 182-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25886968

RESUMEN

To select a specifically binding peptide for imaging detection of human esophageal squamous cell carcinoma (ESCC), a phage-displayed 12-mer peptide library was used to screen the peptide that bind to ESCC cells specifically. After four rounds of bio-panning, the phage recovery rate gradually increased, and specific phage clones were effectively enriched. The 60 randomly selected phage clones were tested using cellular enzyme-linked immunosorbent assay (ELISA), and 41 phage clones were identified as positive clones with the over 2.10 ratio of absorbance higher than other clones, IRP and PBS controls. From the sequencing results of the positive clones, 14 peptide sequences were obtained and ESCP9 consensus sequence was identified as the peptide with best affinity to ESCC cells via competitive inhibition, fluorescence microscopy, and flow cytometry. The results indicate that the peptide ESCP9 can bind to ESCC cells specifically and sensitively, and it is a potential candidate to be developed as an useful molecule to the imaging detection and targeting therapy for ESCC.


Asunto(s)
Bacteriófagos/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Biblioteca de Péptidos , Péptidos/metabolismo , Bacteriófagos/química , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Células HEK293 , Humanos , Péptidos/química , Sensibilidad y Especificidad
19.
Infect Immun ; 82(9): 3753-63, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24958710

RESUMEN

Intestinal epithelial cells (IECs), including secretory goblet cells, form essential physiochemical barriers that separate luminal bacteria from underlying immune cells in the intestinal mucosa. IECs are common targets for enteric bacterial pathogens, with hosts responding to these microbes through innate toll-like receptors that predominantly signal through the MyD88 adaptor protein. In fact, MyD88 signaling confers protection against several enteric bacterial pathogens, including Salmonella enterica serovar Typhimurium and Citrobacter rodentium. Since IECs are considered innately hyporesponsive, it is unclear whether MyD88 signaling within IECs contributes to this protection. We infected mice lacking MyD88 solely in their IECs (IEC-Myd88(-/-)) with S. Typhimurium. Compared to wild-type (WT) mice, infected IEC-Myd88(-/-) mice suffered accelerated tissue damage, exaggerated barrier disruption, and impaired goblet cell responses (Muc2 and RELMß). Immunostaining revealed S. Typhimurium penetrated the IECs of IEC-Myd88(-/-) mice, unlike in WT mice, where they were sequestered to the lumen. When isolated crypts were assayed for their antimicrobial actions, crypts from IEC-Myd88(-/-) mice were severely impaired in their antimicrobial activity against S. Typhimurium. We also examined whether MyD88 signaling in IECs impacted host defense against C. rodentium, with IEC-Myd88(-/-) mice again suffering exaggerated tissue damage, impaired goblet cell responses, and reduced antimicrobial activity against C. rodentium. These results demonstrate that MyD88 signaling within IECs plays an important protective role at early stages of infection, influencing host susceptibility to infection by controlling the ability of the pathogen to reach and survive at the intestinal mucosal surface.


Asunto(s)
Antiinfecciosos/inmunología , Colitis/inmunología , Células Caliciformes/inmunología , Mucosa Intestinal/inmunología , Factor 88 de Diferenciación Mieloide/inmunología , Transducción de Señal/inmunología , Animales , Citrobacter rodentium/inmunología , Colitis/microbiología , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/microbiología , Células Epiteliales/inmunología , Células Epiteliales/microbiología , Gastroenteritis/inmunología , Gastroenteritis/microbiología , Tracto Gastrointestinal/inmunología , Tracto Gastrointestinal/microbiología , Células Caliciformes/microbiología , Mucosa Intestinal/microbiología , Ratones , Ratones Endogámicos C57BL , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/microbiología , Salmonella typhimurium/inmunología
20.
J Cell Physiol ; 229(3): 287-91, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23939989

RESUMEN

Numerous evidences have indicated that a signal system is composed by signal pathways, each pathway is composed by sub-pathways, and the sub-pathway is composed by the original signal terminals initiated with a protein/gene. We infer the terminal signals merged signal transduction system as "signal basin". In this article, we discussed the composition and regulation of signal basins, and the relationship between the signal basin control and triple W of spatiotemporal cell biology. Finally, we evaluated the importance of the systemic regulation to gene expression by signal basins under triple W. We hope our discussion will be the beginning to cause the attention for this area from the scientists of life science.


Asunto(s)
Biología Celular , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Transducción de Señal , Biología de Sistemas , Animales , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Modelos Biológicos , Transducción de Señal/genética
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