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1.
J Biol Chem ; 298(1): 101497, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34919963

RESUMEN

The Kv1.3 channel has been widely demonstrated to play crucial roles in the activation and proliferation of T cells, which suggests that selective blockers could serve as potential therapeutics for autoimmune diseases mediated by T cells. We previously described that the toxin mimic FS48 from salivary gland of Xenopsylla cheopis downregulates the secretion of proinflammatory factors by Raw 264.7 cells by blocking the Kv1.3 channel and the subsequent inactivation of the proinflammatory MAPK/NF-κB pathways. However, the effects of FS48 on human T cells and autoimmune diseases are unclear. Here, we described its immunomodulatory effects on human T cells derived from suppression of Kv1.3 channel. Kv1.3 currents in Jurkat T cells were recorded by whole-cell patch-clamp, and Ca2+ influx, cell proliferation, and TNF-α and IL-2 secretion were measured using Fluo-4, CCK-8, and ELISA assays, respectively. The in vivo immunosuppressive activity of FS48 was evaluated with a rat DTH model. We found that FS48 reduced Kv1.3 currents in Jurkat T cells in a concentration-dependent manner with an IC50 value of about 1.42 µM. FS48 also significantly suppressed Kv1.3 protein expression, Ca2+ influx, MAPK/NF-κB/NFATc1 pathway activation, and TNF-α and IL-2 production in activated Jurkat T cells. Finally, we show that FS48 relieved the DTH response in rats. We therefore conclude that FS48 can block the Kv1.3 channel and inhibit human T cell activation, which most likely contributes to its immunomodulatory actions and highlights the great potential of this evolutionary-guided peptide as a drug template in future studies.


Asunto(s)
Enfermedades Autoinmunes , Canal de Potasio Kv1.3 , Venenos de Escorpión , Linfocitos T , Xenopsylla , Adyuvantes Inmunológicos/farmacología , Animales , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/inmunología , Humanos , Factores Inmunológicos/farmacología , Interleucina-2/metabolismo , Canal de Potasio Kv1.3/inmunología , Activación de Linfocitos/efectos de los fármacos , FN-kappa B/metabolismo , Bloqueadores de los Canales de Potasio/inmunología , Ratas , Glándulas Salivales/química , Venenos de Escorpión/farmacología , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Xenopsylla/química
2.
J Biol Chem ; 296: 100670, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33864815

RESUMEN

The voltage-gated potassium (Kv) 1.3 channel plays a crucial role in the immune responsiveness of T-lymphocytes and macrophages, presenting a potential target for treatment of immune- and inflammation related-diseases. FS48, a protein from the rodent flea Xenopsylla cheopis, shares the three disulfide bond feature of scorpion toxins. However, its three-dimensional structure and biological function are still unclear. In the present study, the structure of FS48 was evaluated by circular dichroism and homology modeling. We also described its in vitro ion channel activity using patch clamp recording and investigated its anti-inflammatory activity in LPS-induced Raw 264.7 macrophage cells and carrageenan-induced paw edema in mice. FS48 was found to adopt a common αßß structure and contain an atypical dyad motif. It dose-dependently exhibited the Kv1.3 channel in Raw 264.7 and HEK 293T cells, and its ability to block the channel pore was demonstrated by the kinetics of activation and competition binding with tetraethylammonium. FS48 also downregulated the secretion of proinflammatory molecules NO, IL-1ß, TNF-α, and IL-6 by Raw 264.7 cells in a manner dependent on Kv1.3 channel blockage and the subsequent inactivation of the MAPK/NF-κB pathways. Finally, we observed that FS48 inhibited the paw edema formation, tissue myeloperoxidase activity, and inflammatory cell infiltrations in carrageenan-treated mice. We therefore conclude that FS48 identified from the flea saliva is a novel potassium channel inhibitor displaying anti-inflammatory activity. This discovery will promote understanding of the bloodsucking mechanism of the flea and provide a new template molecule for the design of Kv1.3 channel blockers.


Asunto(s)
Antiinflamatorios/farmacología , Edema/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Canal de Potasio Kv1.3/antagonistas & inhibidores , Macrófagos/efectos de los fármacos , Glándulas Salivales/metabolismo , Venenos de Escorpión/química , Animales , Edema/inmunología , Edema/metabolismo , Edema/patología , Femenino , Humanos , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Ratones , FN-kappa B/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/metabolismo , Xenopsylla
3.
Biochem Biophys Res Commun ; 571: 20-25, 2021 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-34303191

RESUMEN

Lipopolysaccharide (LPS) is an essential component of the outer membrane (OM) in most Gram-negative bacteria. LPS transport from the inner membrane (IM) to the OM is achieved by seven lipopolysaccharide transport proteins (LptA-G). LptB2FG, an type VI ATP-binding cassette (ABC) transporter, forms a stable complex with LptC, extracts LPS from the IM and powers LPS transport to the OM. Here we report the cryo-EM structures of LptB2FG and LptB2FGC from Klebsiella pneumoniae in complex with LPS. The KpLptB2FG-LPS structure provides detailed interactions between LPS and the transporter, while the KpLptB2FGC-LPS structure may represent an intermediate state that the transmembrane helix of LptC has not been fully inserted into the transmembrane domains of LptB2FG.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/química , Klebsiella pneumoniae/química , Lipopolisacáridos/química , Microscopía por Crioelectrón , Conformación Proteica
4.
J Nat Prod ; 84(12): 3147-3160, 2021 12 24.
Artículo en Inglés | MEDLINE | ID: mdl-34866381

RESUMEN

Smp43, a cationic antimicrobial peptide identified from the venom gland of the Egyptian scorpion Scorpio maurus palmatus, shows cytotoxicity toward hepatoma cell line HepG2 by membrane disruption. However, its underlying detailed mechanisms still remain to be further clarified. In the present study, we evaluated the cellular internalization of Smp43 and explored its effects on cell viability, cell cycle, apoptosis, autophagy, necrosis, and factor expression related to these cellular processes in human HepG2. Smp43 was found to suppress the growth of HepG2, Huh7, and human primary hepatocellular carcinoma cells while showing low toxicity to normal LO2 cells. Furthermore, Smp43 could interact with the cell membrane and be internalized into HepG2 cells via endocytosis and pore formation, which caused a ROS production increase, mitochondrial membrane potential decline, cytoskeleton disorganization, dysregulation of cyclin expression, mitochondrial apoptotic pathway activation, and alteration of MAPK as well as PI3K/Akt/mTOR signaling pathways. Finally, Smp43 showed effective antitumor protection in the HepG2 xenograft mice model. Overall, these findings indicate that Smp43 significantly exerts antitumor effects via induction of apoptosis, autophagy, necrosis, and cell cycle arrest due to its induction of mitochondrial dysfunction and membrane disruption. This discovery will extend the antitumor mechanisms of antimicrobial peptides and contribute to the development of antitumor agents against hepatocellular carcinoma.


Asunto(s)
Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Mitocondrias Hepáticas/efectos de los fármacos , Péptidos/farmacología , Venenos de Escorpión/química , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Endocitosis/efectos de los fármacos , Humanos , Ratones , Membranas Mitocondriales/efectos de los fármacos , Péptidos/química , Péptidos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Ann Intern Med ; 172(1): 1-11, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31711111

RESUMEN

Background: The 3 Wishes Project (3WP) is an end-of-life program that aims to honor the dignity of dying patients by creating meaningful patient- and family-centered memories while promoting humanistic interprofessional care. Objective: To determine whether this palliative intervention could be successfully implemented-defined as demonstrating value, transferability, affordability, and sustainability-beyond the intensive care unit in which it was created. Design: Mixed-methods formative program evaluation. (ClinicalTrials.gov: NCT04147169). Setting: 4 North American intensive care units. Participants: Dying patients, their families, clinicians, hospital managers, and administrators. Intervention: Wishes from dying patients, family members, and clinicians were elicited and implemented. Measurements: Patient characteristics and processes of care; the number, type, and cost of each wish; and semistructured interviews and focus groups with family members, clinicians, and managers. Results: A total of 730 patients were enrolled, and 3407 wishes were elicited. Qualitative data were gathered from 75 family members, 72 clinicians, and 20 managers or hospital administrators. Value included intentional comforting of families as they honored the lives and legacies of their loved ones while inspiring compassionate clinical care. Factors promoting transferability included family appreciation and a collaborative intensive care unit culture committed to dignity-conserving end-of-life care. Staff participation evolved from passive support to professional agency. Program initiation required minimal investment for reusable materials; thereafter, the mean cost was $5.19 (SD, $17.14) per wish. Sustainability was demonstrated by the continuation of 3WP at each site after study completion. Limitation: This descriptive formative evaluation describes tertiary care center-specific experiences rather than aiming for generalizability to all jurisdictions. Conclusion: The 3WP is a transferrable, affordable, and sustainable program that provides value to dying patients, their families, clinicians, and institutions. Primary Funding Source: Greenwall Foundation.


Asunto(s)
Empatía , Cuidado Terminal , Familia/psicología , Femenino , Grupos Focales , Humanos , Unidades de Cuidados Intensivos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Cuidado Terminal/métodos , Cuidado Terminal/organización & administración
6.
Langmuir ; 36(34): 10210-10217, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32787045

RESUMEN

Perovskite nanomaterials have been fascinating for commercial applications and fundamental research owing to their excellent optical properties and satisfactory processability. They are expected to be alternative downconversion materials in phosphor-converted LEDs for lighting or display technology. However, owing to their low formation energy and large specific surface area, perovskite nanomaterials are sensitive to environmental stress like humidity, heat, etc. In this paper, cubic CsPbI3 quantum dots (QDs) with improved stability are synthesized using (3-aminopropyl)triethoxysilane (APTES). These luminescent CsPbI3 QDs passivated by APTES not only show excellent stability when stored in hexane but also possess outstanding steadiness for lattice structure when prepared as a thin film in open air. They do not decompose immediately in the water. Such excellent stability is attributed to the hindrance from hydrolysis of APTES, which forms an analogous core-shell structure to protect the "core" CsPbI3 QDs. Furthermore, an additional iodine source is added to enhance their emissionm and CsPbI3QDs with a PLQY of 84% are synthesized.

7.
J Pept Sci ; 26(8): e3269, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32558003

RESUMEN

The inflammatory response plays important roles in acne vulgaris and pain pathogenesis. In previous study, Esc-1GN with anti-inflammatory, antimicrobial, and lipopolysacchride (LPS) binding activity was identified from the skin of the frog Hylarana guentheri. Here, we report its therapeutic potentials for acne vulgaris and inflammatory pain. Esc-1GN destroyed the cell membrane of Propionibacteria acnes in the membrane permeability assays. In addition, bacterial agglutination test suggested that Esc-1GN triggered the agglutination of P. acnes, which was affected by LPS and Ca2+ . Meanwhile, in vivo anti-P. acnes and anti-inflammatory effects of Esc-1GN were confirmed by reducing the counts of P. acnes in mice ear, relieving P. acnes-induced mice ear swelling, decreasing mRNA expression and the production of pro-inflammatory cytokines, and attenuating the infiltration of inflammatory cells. Moreover, Esc-1GN also displayed antinociceptive effect in mice induced by acetic acid and formalin. Therefore, Esc-1GN is a promising candidate drug for treatment of acne vulgaris and inflammatory pain.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Antibacterianos/farmacología , Antiinflamatorios no Esteroideos/farmacología , Inflamación/tratamiento farmacológico , Dolor/tratamiento farmacológico , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Propionibacterium acnes/efectos de los fármacos , Acné Vulgar/microbiología , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Ratones , Pruebas de Sensibilidad Microbiana , Proteínas Citotóxicas Formadoras de Poros/síntesis química , Proteínas Citotóxicas Formadoras de Poros/química
8.
J Intensive Care Med ; 35(10): 1123-1128, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30572756

RESUMEN

PURPOSE: Passive leg raise (PLR), in combination with technologies capable of capturing stroke volume changes, has been widely adopted in the management of shock. However, dedicated evaluation of safety, feasibility, and receptiveness of patients and nursing staff to PLR maneuver is missing. METHODS: A noninterventional, prospective trial recruited adult patients with onset of undifferentiated shock within 24 hours with persistent vasopressor requirements despite fluid resuscitation. A standardized PLR maneuver was used to compare two noninvasive hemodynamic monitoring systems, each without significant impact on the performance of the maneuver. Safety and efficacy of the PLR were evaluated via subjective and objective measures. Objective measures of patient comfort and tolerance were evaluated through changes in vital signs, sedation, and analgesia requirements. Nurses and awake patients completed surveys on their experience. RESULTS: Seventy-nine patients were enrolled. Testing was aborted in 2 cases for medical reasons (one patient developed rapid atrial fibrillation, second had profound desaturation). Of all, 5.4% of patients required additional vasopressor support after completion of the PLR maneuver due to persistent hypotension and 4.1% of patients required additional sedation. Among awake patients (N = 35), 6% reported pain and 29% reported discomfort. A total of 11% of nurses reported minor technical difficulties with the maneuver. CONCLUSION: Passive leg raise maneuver leads to a few serious but reversible complications in a selected population of hemodynamically unstable patients. Although it provides relevant diagnostic information, it may impact patient care. Treating physician should be aware of infrequent but possible complications and appreciate the impact of the maneuver on patients' comfort and nursing workload.


Asunto(s)
Cuidados Críticos/métodos , Aceptación de la Atención de Salud/estadística & datos numéricos , Posicionamiento del Paciente/métodos , Choque/terapia , Anciano , Analgesia/estadística & datos numéricos , Estudios de Factibilidad , Femenino , Hemodinámica , Humanos , Hipnóticos y Sedantes/uso terapéutico , Unidades de Cuidados Intensivos , Pierna , Masculino , Persona de Mediana Edad , Postura , Estudios Prospectivos , Choque/fisiopatología , Resultado del Tratamiento
9.
BMC Biol ; 16(1): 107, 2018 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-30249243

RESUMEN

BACKGROUND: The hierarchical organization of eukaryotic chromatin plays a central role in gene regulation, by controlling the extent to which the transcription machinery can access DNA. The histone variants H3.3 and H2A.Z have recently been identified as key regulatory players in this process, but the underlying molecular mechanisms by which they permit or restrict gene expression remain unclear. Here, we investigated the regulatory function of H3.3 and H2A.Z on chromatin dynamics and Polycomb-mediated gene silencing. RESULTS: Our ChIP-seq analysis reveals that in mouse embryonic stem (mES) cells, H3K27me3 enrichment correlates strongly with H2A.Z. We further demonstrate that H2A.Z promotes PRC2 activity on H3K27 methylation through facilitating chromatin compaction both in vitro and in mES cells. In contrast, PRC2 activity is counteracted by H3.3 through impairing chromatin compaction. However, a subset of H3.3 may positively regulate PRC2-dependent H3K27 methylation via coordinating depositions of H2A.Z to developmental and signaling genes in mES cells. Using all-trans retinoic acid (tRA)-induced gene as a model, we show that the dynamic deposition of H2A.Z and H3.3 coordinately regulates the PRC2-dependent H3K27 methylation by modulating local chromatin structure at the promoter region during the process of turning genes off. CONCLUSIONS: Our study provides key insights into the mechanism of how histone variants H3.3 and H2A.Z function coordinately to finely tune the PRC2 enzymatic activity during gene silencing, through promoting or impairing chromosome compaction respectively.


Asunto(s)
Cromatina/metabolismo , Regulación de la Expresión Génica , Histonas/genética , Complejo Represivo Polycomb 2/genética , Animales , Línea Celular , Histonas/metabolismo , Ratones , Células Madre Embrionarias de Ratones , Complejo Represivo Polycomb 2/metabolismo
10.
Anticancer Drugs ; 29(9): 880-889, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29912729

RESUMEN

Voltage-gated sodium channel activity enhances the motility and oncogene expression of metastasic cancer cells that express a neonatal alternatively spliced form of the NaV1.5 isoform. We reported previously that FS50, a salivary protein from Xenopsylla cheopis, showed inhibitory activity against the NaV1.5 channel when assayed in HEK 293T cells and antiarrhythmia effects on rats and monkeys after induction of arrhythmia by BaCl2. This study aims to identify the effect of FS50 on voltage-gated sodium channel activity and the motility of MDA-MB-231 human breast cancer cells in vitro. NaV1.5 was abnormally expressed in the highly metastatic breast cancer cell line MDA-MB-231, but not in the MCF-7 cell line. FS50 significantly inhibited sodium current, migration, and invasion in a dose-dependent manner, but had no effect on the proliferation of MDA-MB-231 cells at the working concentrations (1.5-12 µmol/l) after a long-term treatment for 48 h. Meanwhile, FS50 decreased NaV1.5 mRNA expression without altering the total protein level in MDA-MB-231 cells. Correspondingly, the results also showed that MMP-9 activity and the ratio of MMP-9 mRNA to TIMP-1 mRNA were markedly decreased by FS50. Taken together, our findings highlighted for the first time an inhibitory effect of a salivary protein from a blood-feeding arthropod on breast cancer cells through the NaV1.5 channel. Furthermore, this study provided a new candidate leading molecule against antitumor cells expressing NaV1.5.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Canal de Sodio Activado por Voltaje NAV1.5/efectos de los fármacos , Proteínas y Péptidos Salivales/farmacología , Xenopsylla/metabolismo , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Células MCF-7 , Metaloproteinasa 9 de la Matriz/genética , Canal de Sodio Activado por Voltaje NAV1.5/genética , ARN Mensajero/metabolismo , Proteínas y Péptidos Salivales/administración & dosificación , Proteínas y Péptidos Salivales/genética , Factores de Tiempo , Inhibidor Tisular de Metaloproteinasa-1/genética
11.
Biochem Biophys Res Commun ; 493(1): 814-820, 2017 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-28842256

RESUMEN

Genomic DNA of eukaryotic cells is hierarchically packaged into chromatin by histones. The dynamic organization of chromatin fibers plays a critical role in the regulation of gene transcription and other DNA-associated biological processes. Recently, numerous approaches have been developed to map the chromatin organization by characterizing chromatin accessibilities in genome-wide. However, reliable methods to quantitatively map chromatin accessibility are not well-established, especially not on a genome-wide scale. Here, we developed a modified MNase-seq for mouse embryonic fibroblasts, wherein chromatin was partially digested at multiple digestion times using micrococcal nuclease (MNase), allowing quantitative analysis of local yet genome-wide chromatin compaction. Our results provide strong evidence that the chromatin accessibility at promoter regions are positively correlated with gene activity. In conclusion, our assay is an ideal tool for the quantitative study of gene regulation in the perspective of chromatin accessibility.


Asunto(s)
Ensamble y Desensamble de Cromatina/genética , Cromatina/genética , Mapeo Cromosómico/métodos , Segregación Cromosómica/genética , Fibroblastos/fisiología , Regiones Promotoras Genéticas/genética , Animales , Sitios de Unión , Células Cultivadas , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Ratones , Análisis de Secuencia de ADN/métodos
12.
J Cell Sci ; 127(Pt 17): 3735-44, 2014 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-24994936

RESUMEN

Epithelial-mesenchymal transition (EMT) is a developmental program that is associated with esophageal squamous cell carcinoma (ESCC) progression and metastasis. Recently, C/EBPß has been reported to be an EMT inducer in cancer. However, the detailed molecular mechanisms remain unclear. Here, we report for the first time, that the truncated CCAAT-enhancer-binding protein ß (C/EBPß) LIP isoform is abnormally overexpressed and correlated with cancer metastasis in clinical specimens of human ESCC. Furthermore, we demonstrate that C/EBPß LIP mediates epithelial growth factor (EGF)-induced EMT and increases migration and invasion of esophageal cancer cells in a manner that is dependent on miR-203 inactivation. Finally, we identified miR-203 as a direct target of C/EBPß LIP. Disruption of C/EBPß LIP attenuated the EGF-mediated decrease in miR-203, whereas overexpression of C/EBPß LIP alone markedly suppressed miR-203. In addition, we demonstrated that C/EBPß LIP inhibited miR-203 transcription by directly interacting with a conserved distal regulatory element upstream of the miR-203 locus, and in doing so, orchestrated chromatin remodeling. In conclusion, our results have revealed a new regulatory mechanism that involves C/EBPß-LIP-mediated downregulation of miR-203, which plays a key role in EMT and metastasis.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT/genética , Carcinoma de Células Escamosas/metabolismo , Factor de Crecimiento Epidérmico/metabolismo , Transición Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/metabolismo , Línea Celular Tumoral , Células Epiteliales/metabolismo , Transición Epitelial-Mesenquimal/fisiología , Carcinoma de Células Escamosas de Esófago , Humanos
13.
Tumour Biol ; 37(1): 425-35, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26219897

RESUMEN

When cancer cells have been cultured as three-dimensional (3D) cultures or in vivo, they decrease sensitivity to anticancer drugs. This is called multicellular resistance, and the mechanism is not fully understood. Here, we report that E-cadherin increasing multidrug resistance protein 1 (MDR1) via hypoxia-inducible factor-1α (HIF-1α) contributes to multicellular resistance in colorectal cancer. The MDR1 protein level was higher in 3D cultures than in monolayer cells. When dispersed cells from 3D cultures were grown as monolayer cells again, the MDR1 protein level decreased to the similar level of cells maintained as monolayer all through. Knockdown of MDR1 significantly decreased multicellular resistance. Knockdown of E-cadherin decreased MDR1 in 3D cultures but did not detectably change MDR1 in monolayer cells. E-cadherin was expressed uniformly in 3D cultures while the MDR1 protein level was higher in the center of 3D cultures than in the peripheral part. Knockdown of E-cadherin decreased E-cadherin uniformly in 3D cultures but mainly decreased MDR1 at the center of 3D cultures. These suggest that knockdown of E-cadherin decreasing MDR1 may be by an indirect mechanism. HIF-1α was remarkably increased in 3D cultures. Knockdown of E-cadherin decreased intercellular junctions, increased intercellular space, and decreased HIF-1α in 3D cultures. Knockdown of HIF-1α decreased MDR1 in 3D cultures. Knockdown of E-cadherin increased ß-catenin uniformly in 3D cultures, and knockdown of ß-catenin decreased MDR1 what was opposite to knockdown of E-cadherin decreasing MDR1. Our data reveal that knockdown of E-cadherin decreasing MDR1 via HIF-1α is involved in the mechanism of multicellular resistance in colorectal cancer. Though ß-catenin is also involved in the mechanism, it does not play a dominant role.


Asunto(s)
Cadherinas/metabolismo , Neoplasias Colorrectales/metabolismo , Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Antígenos CD , Apoptosis , Línea Celular Tumoral , Células HCT116 , Células HEK293 , Humanos , beta Catenina/metabolismo
14.
J Cell Physiol ; 230(4): 903-10, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25216463

RESUMEN

miR-203 act as tumor repressor by inhibiting cell proliferation and is repressed in a variety of human tumors, although the molecular mechanisms responsible have not been elucidated. Here, we reveal that miR-203 is regulated by E2F1, an important transcription factor that can induce cell proliferation by controlling cell cycle progression. We found that miR-203 expression was induced by cisplatin, which also induced E2F1 protein accumulation in esophageal squamous cell carcinoma (ESCC) cell lines. miR-203 expression was elevated upon activation of ectopic E2F1, whereas this induction was abolished when the E2F1 gene was silenced. Moreover, with luciferase reporter assays and chromatin immunoprecipitation (ChIP) assays, we demonstrated that E2F1 transactivates miR-203 by directly binding to the miR-203 gene promoter. In addition, we found that miR-203 inhibited cell proliferation by inducing G1/S cell cycle arrest, but not apoptosis, in ESCC cell lines. Finally, we observed that miR-203 negatively inhibited the expression of CDK6, subsequently decreasing E2F1 expression possibly through Rb phosphorylation. Taken together, our data show that cancer-related miR-203 is a novel transcriptional target of E2F1 and that it regulates cell cycle arrest by participating in a feedback loop with E2F1.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Puntos de Control del Ciclo Celular , Proliferación Celular/genética , Factor de Transcripción E2F1/metabolismo , Neoplasias Esofágicas/metabolismo , MicroARNs/metabolismo , Apoptosis/fisiología , Carcinoma de Células Escamosas/genética , Puntos de Control del Ciclo Celular/genética , Puntos de Control del Ciclo Celular/fisiología , Línea Celular Tumoral , Proliferación Celular/fisiología , Factor de Transcripción E2F1/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas de Esófago , Regulación Neoplásica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , MicroARNs/genética
15.
J Hepatol ; 62(2): 354-62, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25200905

RESUMEN

BACKGROUND & AIMS: Viral fulminant hepatitis (FH) is a disease with a high mortality rate. Activation of the complement system correlates with the development of FH. However, the key factors mediating complement activation in FH remain elusive. METHODS: Liver tissues were isolated from FH patients infected by hepatitis B virus (HBV) and from mice infected with murine hepatitis virus strain 3 (MHV-3). Wild type mice were treated with or without antagonists of C5aR or TNF-α, and mice deficient for C5aR (C5aR(-/-)), Fgl2 (Fgl2(-/-)), and Tnfα (Tnfα(-/-)) mice were not treated with the antagonists. C5b-9, C5aR, FGL2, CD31, CD11b, fibrin, TNF-α, and complement C3 cleavage products were detected by immunohistochemistry, immunofluorescence, or ELISA. Sorted liver sinusoidal endothelial cells (LSECs) or myeloid-derived (CD11b(+)) cells were stimulated with C5a, TNF-α or MHV-3 in vitro. The mRNA expressions levels of Fgl2 and Tnfα were determined by qRT-PCR analyses. RESULTS: We observed that complement activation, coagulation and pro-inflammatory cytokine production were upregulated in the HBV(+) patients with FH. Similar observations were made in the murine FH models. Complement activation and coagulation were significantly reduced in MHV-3 infected mice in the absence of C5aR, Tnfα or Fgl2. The MHV-3 infected C5aR(-/-) mice exhibited reduced numbers of infiltrated inflammatory CD11b(+) cells and a reduced expression of TNF-α and FGL2. Moreover, C5a administration stimulated TNF-α production by CD11b(+) cells, which in turn promoted the expression of FGL2 in CD31(+) LSEC-like cells in vitro. Administration of antagonists against C5aR or TNF-α ameliorated MHV-3-induced FH. CONCLUSIONS: Our results demonstrate that C5aR, TNF-α, and FGL2 form an integral network that contributes to coagulation and complement activation, and suggest that those are potential therapeutic targets in viral FH intervention.


Asunto(s)
Coagulación Sanguínea/genética , Activación de Complemento/genética , Fibrinógeno/genética , Regulación de la Expresión Génica , Hepatitis Viral Animal/metabolismo , Receptor de Anafilatoxina C5a/genética , Factor de Necrosis Tumoral alfa/genética , Animales , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Fibrinógeno/biosíntesis , Hepatitis Viral Animal/patología , Hepatitis Viral Animal/virología , Humanos , Inmunohistoquímica , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Virus de la Hepatitis Murina/patogenicidad , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor de Anafilatoxina C5a/biosíntesis , Linfocitos T , Factor de Necrosis Tumoral alfa/biosíntesis
16.
Biochem Biophys Res Commun ; 446(1): 267-71, 2014 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-24589738

RESUMEN

Recent clinical study indicated that up-regulation of miR-146b was associated with poor overall survival of patients in esophageal squamous cell carcinoma. However, the underlying mechanism of miR-146b dysregulation remains to be explored. Here we report that miR-146b promotes cell proliferation and inhibits cell apoptosis in esophageal cancer cell lines. Mechanismly, two C/EBPß binding motifs are located in the miR-146b promoter conserved region. Among the three isoforms of C/EBPß, C/EBPß LAP2 positively regulated miR-146b expression and increases miR-146b levels in a dose-dependent manner through transcription activation of miR-146b gene. Together, these results suggest a miR-146b regulatory mechanism involving C/EBPß, which may contribute to the up-regulation of miR-146b in esophageal squamous cell carcinoma.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Apoptosis , Secuencia de Bases , Sitios de Unión/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Proliferación Celular , Secuencia Conservada , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago , Regulación Neoplásica de la Expresión Génica , Humanos , Regiones Promotoras Genéticas , Isoformas de Proteínas/metabolismo , Activación Transcripcional , Regulación hacia Arriba
17.
Arterioscler Thromb Vasc Biol ; 33(12): 2759-70, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24092749

RESUMEN

OBJECTIVE: Polyphosphate and heparin are anionic polymers released by activated mast cells and platelets that are known to stimulate the contact pathway of coagulation. These polymers promote both the autoactivation of factor XII and the assembly of complexes containing factor XI, prekallikrein, and high-molecular-weight kininogen. We are searching for salivary proteins from blood-feeding insects that counteract the effect of procoagulant and proinflammatory factors in the host, including elements of the contact pathway. APPROACH AND RESULTS: Here, we evaluate the ability of the sand fly salivary proteins, PdSP15a and PdSP15b, to inhibit the contact pathway by disrupting binding of its components to anionic polymers. We attempt to demonstrate binding of the proteins to polyphosphate, heparin, and dextran sulfate. We also evaluate the effect of this binding on contact pathway reactions. We also set out to determine the x-ray crystal structure of PdSP15b and examine the determinants of relevant molecular interactions. Both proteins bind polyphosphate, heparin, and dextran sulfate with high affinity. Through this mechanism they inhibit the autoactivation of factor XII and factor XI, the reciprocal activation of factor XII and prekallikrein, the activation of factor XI by thrombin and factor XIIa, the cleavage of high-molecular-weight kininogen in plasma, and plasma extravasation induced by polyphosphate. The crystal structure of PdSP15b contains an amphipathic helix studded with basic side chains that forms the likely interaction surface. CONCLUSIONS: The results of these studies indicate that the binding of anionic polymers by salivary proteins is used by blood feeders as an antihemostatic/anti-inflammatory mechanism.


Asunto(s)
Anticoagulantes/farmacología , Coagulación Sanguínea/efectos de los fármacos , Sulfato de Dextran/metabolismo , Heparina/metabolismo , Proteínas de Insectos/farmacología , Polifosfatos/metabolismo , Psychodidae/química , Saliva/química , Animales , Anticoagulantes/química , Anticoagulantes/aislamiento & purificación , Anticoagulantes/metabolismo , Pruebas de Coagulación Sanguínea , Permeabilidad Capilar/efectos de los fármacos , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Factor XIIa/antagonistas & inhibidores , Factor XIIa/metabolismo , Factor XIa/antagonistas & inhibidores , Factor XIa/metabolismo , Humanos , Proteínas de Insectos/química , Proteínas de Insectos/aislamiento & purificación , Proteínas de Insectos/metabolismo , Quininógeno de Alto Peso Molecular/antagonistas & inhibidores , Quininógeno de Alto Peso Molecular/metabolismo , Ratones , Modelos Moleculares , Precalicreína/antagonistas & inhibidores , Precalicreína/metabolismo , Conformación Proteica , Relación Estructura-Actividad , Trombina/metabolismo , Factores de Tiempo
18.
Front Public Health ; 12: 1377305, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39171306

RESUMEN

Purpose: Against the background of population aging challenges in China, focusing on health, security, and social participation as core elements of positive aging, this study aims to formulate strategies for promoting the health of the older adults and reveal the pathways and trends of social participation in promoting health. Method: The study analyzed 1,015 randomly selected older adults individuals living at home in Beijing using household survey questionnaires. Drawing on group dynamics theory and structural equation modeling, the study proposed hypotheses regarding the relationships between social participation, group cohesion, and health status. Results: First, the triangular path model of social participation, group cohesion, and health status among the older adults was established. The direct path coefficient of social participation on health status was 0.15, that of social participation on group cohesion was 0.56, and that of group cohesion on health status was 0.32. The indirect path coefficient of social participation on health status through group cohesion was calculated at 0.56 × 0.32 = 0.18. Second, of the older adults age groups-younger, middle, and older-social participation's direct path effects on health status were present only in the older age group. Social participation's indirect path effects on health status through group cohesion were relatively high in all three groups, with a slight increase in the older age group. Conclusion: First, just the older adults participation in social activities serves as a benign stimulus to physical and mental health. Additionally, group cohesion formed through interaction with others during social activities encourages self-improvement behaviors, indirectly promoting health. In fact, indirect pathways of health promotion through group cohesion are stronger than direct pathways, highlighting the importance of group cohesion during social participation. Second, participation in activities alone can provide only sufficient benign stimuli for the older adults aged 80 and above, with the direct path effect of social participation on health beginning to appear only with increasing age. With age, selectivity of interaction with others decreases, and dependence increases; social participation's indirect path effect on health through group cohesion continues to grow slightly.


Asunto(s)
Estado de Salud , Participación Social , Humanos , Anciano , Masculino , Femenino , Encuestas y Cuestionarios , Persona de Mediana Edad , Anciano de 80 o más Años , China , Beijing , Envejecimiento/psicología
19.
Stem Cell Res ; 76: 103357, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38412658

RESUMEN

INF2 mutations cause Charcot-Marie-Tooth disease (CMT), and /or focal segmental glomerulosclerosis (FSGS) in an autosomal dominant inheritance mode, whose underlying mechanism remainsunclear. Here, we report the generation of an iPSC line from a female patient with CMT and FSGS. The iPSC line from the patient's PBMCscarried aheterozygous INF2 deletion mutation (c.315_323delGCGCGCCGT) within the conserved E2. This line exhibited a normal karyotype, high expression of pluripotency markers, and trilineage differentiation potential. This line can be used to dissect the complex pathomechanism through further induction of differentiation into related cells and as a drug screening tool for INF2-associated diseases.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth , Glomeruloesclerosis Focal y Segmentaria , Células Madre Pluripotentes Inducidas , Humanos , Femenino , Glomeruloesclerosis Focal y Segmentaria/genética , Enfermedad de Charcot-Marie-Tooth/genética , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Forminas/genética , Células Madre Pluripotentes Inducidas/metabolismo , Mutación
20.
Stem Cell Res ; 77: 103439, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38761687

RESUMEN

Hypophosphatemic vitamin D-resistant rickets typically presents in infancy or early childhood with skeletal deformities and growth plate abnormalities. In this report, the SMUSHi005-A human induced pluripotent stem cell (hiPSC) line was successfully established from the PBMCs of a female patient carrying the PHEX mutation with c.1586-1586+1 delAG. The iPSC line has been confirmed to have a normal karyotype. The displayed cells clearly exhibit characteristics similar to embryonic stem cells, expressing pluripotency markers and demonstrating the ability to differentiate into three germ layers.


Asunto(s)
Células Madre Pluripotentes Inducidas , Mutación , Endopeptidasa Neutra Reguladora de Fosfato PHEX , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Femenino , Endopeptidasa Neutra Reguladora de Fosfato PHEX/genética , Línea Celular , Raquitismo Hipofosfatémico Familiar/genética , Raquitismo Hipofosfatémico Familiar/patología , Diferenciación Celular , Raquitismo Hipofosfatémico/genética , Vitamina D/análogos & derivados
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