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1.
Cell ; 178(5): 1072-1087.e14, 2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-31442401

RESUMEN

Nutritional status potentially influences immune responses; however, how nutritional signals regulate cellular dynamics and functionality remains obscure. Herein, we report that temporary fasting drastically reduces the number of lymphocytes by ∼50% in Peyer's patches (PPs), the inductive site of the gut immune response. Subsequent refeeding seemingly restored the number of lymphocytes, but whose cellular composition was conspicuously altered. A large portion of germinal center and IgA+ B cells were lost via apoptosis during fasting. Meanwhile, naive B cells migrated from PPs to the bone marrow during fasting and then back to PPs during refeeding when stromal cells sensed nutritional signals and upregulated CXCL13 expression to recruit naive B cells. Furthermore, temporal fasting before oral immunization with ovalbumin abolished the induction of antigen-specific IgA, failed to induce oral tolerance, and eventually exacerbated food antigen-induced diarrhea. Thus, nutritional signals are critical in maintaining gut immune homeostasis.


Asunto(s)
Linfocitos B/fisiología , Inmunidad Mucosa , Animales , Antígenos/inmunología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Médula Ósea/inmunología , Médula Ósea/metabolismo , Quimiocina CXCL13/genética , Quimiocina CXCL13/metabolismo , Ayuno , Regulación de la Expresión Génica , Glucólisis , Inmunoglobulina A/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Estado Nutricional , Ovalbúmina/inmunología , Ganglios Linfáticos Agregados/inmunología , Ganglios Linfáticos Agregados/metabolismo , Ganglios Linfáticos Agregados/patología , Receptores CXCR5/genética , Receptores CXCR5/metabolismo , Transducción de Señal , Células del Estroma/citología , Células del Estroma/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
2.
Nat Immunol ; 15(6): 571-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24777532

RESUMEN

Intestinal regulatory T cells (Treg cells) are necessary for the suppression of excessive immune responses to commensal bacteria. However, the molecular machinery that controls the homeostasis of intestinal Treg cells has remained largely unknown. Here we report that colonization of germ-free mice with gut microbiota upregulated expression of the DNA-methylation adaptor Uhrf1 in Treg cells. Mice with T cell-specific deficiency in Uhrf1 (Uhrf1(fl/fl)Cd4-Cre mice) showed defective proliferation and functional maturation of colonic Treg cells. Uhrf1 deficiency resulted in derepression of the gene (Cdkn1a) that encodes the cyclin-dependent kinase inhibitor p21 due to hypomethylation of its promoter region, which resulted in cell-cycle arrest of Treg cells. As a consequence, Uhrf1(fl/fl)Cd4-Cre mice spontaneously developed severe colitis. Thus, Uhrf1-dependent epigenetic silencing of Cdkn1a was required for the maintenance of gut immunological homeostasis. This mechanism enforces symbiotic host-microbe interactions without an inflammatory response.


Asunto(s)
Colitis/inmunología , Colon/inmunología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Epigénesis Genética , Proteínas Nucleares/inmunología , Linfocitos T Reguladores/inmunología , Traslado Adoptivo , Animales , Proteínas Potenciadoras de Unión a CCAAT , Puntos de Control del Ciclo Celular , Proliferación Celular , Células Cultivadas , Clostridium/inmunología , Colitis/genética , Colon/microbiología , Metilación de ADN , Perfilación de la Expresión Génica , Interleucina-2 , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Microbiota/inmunología , Proteínas Nucleares/biosíntesis , Proteínas Nucleares/genética , Regiones Promotoras Genéticas , Interferencia de ARN , ARN Interferente Pequeño , Simbiosis/inmunología , Ubiquitina-Proteína Ligasas , Regulación hacia Arriba
3.
Gastroenterology ; 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38971198

RESUMEN

BACKGROUND & AIMS: Guidelines recommend use of risk stratification scores for patients presenting with gastrointestinal bleeding (GIB) to identify very-low-risk patients eligible for discharge from emergency departments. Machine learning models may outperform existing scores and can be integrated within the electronic health record (EHR) to provide real-time risk assessment without manual data entry. We present the first EHR-based machine learning model for GIB. METHODS: The training cohort comprised 2,546 patients and internal validation of 850 patients presenting with overt GIB (hematemesis, melena, hematochezia) to emergency departments of 2 hospitals from 2014-2019. External validation was performed on 926 patients presenting to a different hospital with the same EHR from 2014-2019. The primary outcome was a composite of red-blood-cell transfusion, hemostatic intervention (endoscopic, interventional radiologic, or surgical), and 30-day all-cause mortality. We used structured data fields in the EHR available within 4 hours of presentation and compared performance of machine learning models to current guideline-recommended risk scores, Glasgow-Blatchford Score (GBS) and Oakland Score. Primary analysis was area under the receiver-operating-characteristic curve (AUC). Secondary analysis was specificity at 99% sensitivity to assess proportion of patients correctly identified as very-low-risk. RESULTS: The machine learning model outperformed the GBS (AUC=0.92 vs. 0.89;p<0.001) and Oakland score (AUC=0.92 vs. 0.89;p<0.001). At the very-low-risk threshold of 99% sensitivity, the machine learning model identified more very-low-risk patients: 37.9% vs. 18.5% for GBS and 11.7% for Oakland score (p<0.001 for both comparisons). CONCLUSIONS: An EHR-based machine learning model performs better than currently recommended clinical risk scores and identifies more very-low-risk patients eligible for discharge from the emergency department.

4.
Eur J Immunol ; 54(4): e2350800, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38282083

RESUMEN

Obesity-induced adipose tissue inflammation plays a critical role in the development of metabolic diseases. For example, NK1.1+ group 1 innate lymphoid cells (G1-ILCs) in adipose tissues are activated in the early stages of inflammation in response to a high-fat diet (HFD). In this study, we examined whether the composition of fatty acids affected adipose inflammatory responses induced by an HFD. Mice were fed a stearic acid (C18:0)-rich HFD (HFD-S) or a linoleic acid (C18:2)-rich HFD (HFD-L). HFD-L-fed mice showed significant obesity compared with HFD-S-fed mice. Visceral and subcutaneous fat pads were enlarged and contained more NK1.1+KLRG1+ cells, indicating that G1-ILCs were activated in HFD-L-fed mice. We examined early changes in adipose tissues during the first week of HFD intake, and found that mice fed HFD-L showed increased levels of NK1.1+CD11b+KLRG1+ cells in adipose tissues. In adipose tissue culture, addition of 4-hydroxynonenal, the most frequent product of lipid peroxidation derived from unsaturated fatty acids, induced NK1.1+CD11b+CD27- cells. We found that calreticulin, a ligand for the NK activating receptor, was induced on the surface of adipocytes after exposure to 4-hydroxynonenal or a 1-week feeding with HFD-L. Thus, excess fatty acid intake and the activation of G1-ILCs initiate and/or modify adipose inflammation.


Asunto(s)
Aldehídos , Dieta Alta en Grasa , Ácidos Grasos , Animales , Ratones , Adipocitos , Tejido Adiposo , Calreticulina/metabolismo , Dieta Alta en Grasa/efectos adversos , Ácidos Grasos/metabolismo , Inmunidad Innata , Inflamación/metabolismo , Linfocitos/metabolismo , Obesidad
5.
Int Immunol ; 36(5): 223-240, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38262747

RESUMEN

The gut microbiota plays a crucial role in maintaining epithelial barrier function. Although multiple studies have demonstrated the significance of dietary factors on the gut microbiota and mucosal barrier function, the impact of a purified diet, which has long been used in various animal experiments, on intestinal homeostasis remains to be elucidated. Here, we compared the impact of two different types of diets, a crude diet and an AIN-93G-formula purified diet, on epithelial integrity and the gut microbiota. Purified diet-fed mice exhibited shorter villi and crypt lengths and slower epithelial turnover, particularly in the ileum. In addition, antimicrobial products, including REG3γ, were substantially decreased in purified diet-fed mice. Purified diet feeding also suppressed α1,2-fucosylation on the epithelial surface. Furthermore, the purified diet induced metabolic rewiring to fatty acid oxidation and ketogenesis. 16S ribosomal RNA gene sequencing of the ileal contents and mucus layer revealed distinct gut microbiota compositions between the purified and crude diet-fed mice. Purified diet feeding reduced the abundance of segmented filamentous bacteria (SFB), which potently upregulate REG3γ and fucosyltransferase 2 (Fut2) by stimulating group 3 innate lymphoid cells (ILC3s) to produce IL-22. These observations illustrate that the intake of a crude diet secures epithelial barrier function by facilitating SFB colonization, whereas a purified diet insufficiently establishes the epithelial barrier, at least partly owing to the loss of SFB. Our data suggest that the influence of purified diets on the epithelial barrier integrity should be considered in experiments using purified diets.


Asunto(s)
Microbioma Gastrointestinal , Ratones , Animales , Inmunidad Innata , Linfocitos , Dieta , Bacterias , Proliferación Celular
6.
Ann Surg Oncol ; 31(1): 251-261, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37798554

RESUMEN

BACKGROUND: Preoperative chemotherapy/chemoradiotherapy has been generally considered for the treatment of esophageal squamous cell carcinoma (ESCC) to improve prognosis. We examined the effects of anticancer drugs on the expression of kallikrein-related peptidase 13 (KLK13), a potential ESCC prognostic marker, and its clinical relevance in patients who received chemotherapy/chemoradiotherapy for ESCC. METHODS: Overall, 105 patients with ESCC who received chemotherapy or chemoradiotherapy before esophagectomy were enrolled. The expression of KLK13 in biopsy samples obtained before chemotherapy/chemoradiotherapy and resected ESCC tumors was assessed by immunohistochemical staining. The effects of 5-fluorouracil (5-FU) and/or cisplatin (CDDP) exposure on the expressions of KLK13 and ten-eleven translocation dioxygenases (TET) in ESCC cells were examined by reverse transcription-polymerase chain reaction. RESULTS: Immunohistochemical staining of paired ESCC specimens before (biopsy samples) and after (resected specimens) chemotherapy/chemoradiotherapy demonstrated a change in KLK13 expression. KLK13 and TET2/3 transcriptions were induced when human ESCC cell lines were treated with 5-FU and/or CDDP. Among patients with KLK13-negative status before chemotherapy/chemoradiotherapy, those with KLK13-positive resected tumors had a significantly poorer prognosis than those with KLK13-negative resected tumors (p = 0.0477). By using tumor cells isolated from ESCC biopsy tissues obtained before chemotherapy/chemoradiotherapy, we established a primary culture system and detected the induction of KLK13 expression by anticancer drugs. CONCLUSIONS: Preoperative treatments alter KLK13 expression in ESCC. The conversion of KLK13 expression from a negative status in biopsy samples to a positive status in resected tumor samples is a predictor of poor prognosis. KLK13 status is a potential marker for decision making to avoid harmful chemotherapy/chemoradiotherapy in patients with ESCC.


Asunto(s)
Antineoplásicos , Dioxigenasas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia , Cisplatino/farmacología , Proteínas de Unión al ADN , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas de Esófago/terapia , Fluorouracilo , Calicreínas , Pronóstico , Terapia Neoadyuvante
7.
Arterioscler Thromb Vasc Biol ; 43(9): e358-e372, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37470181

RESUMEN

BACKGROUND: Transmural failure of the aorta is responsible for substantial morbidity and mortality; it occurs when mechanical stress exceeds strength. The aortic root and ascending aorta are susceptible to dissection and rupture in Marfan syndrome, a connective tissue disorder characterized by a progressive reduction in elastic fiber integrity. Whereas competent elastic fibers endow the aorta with compliance and resilience, cross-linked collagen fibers confer stiffness and strength. We hypothesized that postnatal reductions in matrix cross-linking increase aortopathy when turnover rates are high. METHODS: We combined ex vivo biaxial mechanical testing with multimodality histological examinations to quantify expected age- and sex-dependent structural vulnerability of the ascending aorta in Fbn1C1041G/+ Marfan versus wild-type mice without and with 4-week exposures to ß-aminopropionitrile, an inhibitor of lysyl oxidase-mediated cross-linking of newly synthesized elastic and collagen fibers. RESULTS: We found a strong ß-aminopropionitrile-associated sexual dimorphism in aortic dilatation in Marfan mice and aortic rupture in wild-type mice, with dilatation correlating with compromised elastic fiber integrity and rupture correlating with compromised collagen fibril organization. A lower incidence of rupture of ß-aminopropionitrile-exposed Marfan aortas associated with increased lysyl oxidase, suggesting a compensatory remodeling of collagen that slows disease progression in the otherwise compromised Fbn1C1041G/+ aorta. CONCLUSIONS: Collagen fiber structure and function in the Marfan aorta are augmented, in part, by increased lysyl oxidase in female and especially male mice, which improves structural integrity, particularly via fibrils in the adventitia. Preserving or promoting collagen cross-linking may represent a therapeutic target for an otherwise vulnerable aorta.


Asunto(s)
Síndrome de Marfan , Animales , Femenino , Masculino , Ratones , Aminopropionitrilo/toxicidad , Colágeno , Dilatación , Modelos Animales de Enfermedad , Matriz Extracelular/patología , Fibrilina-1/genética , Síndrome de Marfan/complicaciones , Síndrome de Marfan/patología , Ratones Endogámicos C57BL , Proteína-Lisina 6-Oxidasa/genética
8.
Cancer Sci ; 113(1): 195-204, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34726807

RESUMEN

Glutathione S-transferase omega 2 (GSTO2) lacks any appreciable GST activity, but it exhibits thioltransferase activity. The significance of GSTO2 in lung function has been reported; however, the precise expression and molecular function of GSTO2 in the lungs remain unclear. In the present study, we found that GSTO2 is expressed in airway basal cells, non-ciliated, columnar Clara cells, and type II alveolar cells, which have self-renewal capacity in the lungs. Contrastingly, no GSTO2 expression was observed in 94 lung squamous cell carcinoma (LSCC) samples. When human LSCC cell lines were treated with 5-aza-2'-deoxycytidine, a DNA-methyltransferase inhibitor, GSTO2 transcription was induced, suggesting that aberrant GSTO2 hypermethylation in LSCC is the cause of its downregulation. Forced GSTO2 expression in LSCC cell lines inhibited cell growth and colony formation in vitro. In a subcutaneous xenograft model, GSTO2-transfected cells formed smaller tumors in nude mice than mock-transfected cells. Upon intravenous injection into nude mice, the incidence of liver metastasis was lower in mice injected with GSTO2-transfected cells than in those injected with mock-transfected cells. In addition, GSTO2 induction suppressed the expression of ß-catenin and the oxygen consumption rate, but it did not affect the extracellular acidification rate. Furthermore, GSTO2-transfected cells displayed lower mitochondrial membrane potential than mock-transfected cells. When GSTO2-transfected cells were treated with a p38 inhibitor, ß-catenin expression and mitochondrial membrane potential were recovered. Our study indicated that the loss of GSTO2 via DNA hypermethylation contributes to the growth and progression of LSCC, probably by modulating cancer metabolism via the p38/ß-catenin signaling pathway.


Asunto(s)
Carcinoma de Células Escamosas/patología , Regulación hacia Abajo , Glutatión Transferasa/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/patología , Animales , Carcinoma de Células Escamosas/genética , Línea Celular Tumoral , Metilación de ADN/efectos de los fármacos , Decitabina/farmacología , Regulación hacia Abajo/efectos de los fármacos , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glucólisis , Humanos , Neoplasias Hepáticas/genética , Neoplasias Pulmonares/genética , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Fosforilación Oxidativa
9.
Eur Arch Otorhinolaryngol ; 279(10): 4727-4733, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35015092

RESUMEN

PURPOSE: The hearing outcome of idiopathic sudden sensorineural hearing loss (ISSNHL) is hard to predict. We herein constructed a multiple regression model for hearing outcomes in each frequency separately in an attempt to achieve practical prediction in ISSNHL. METHODS: We enrolled 235 consecutive in-patients with ISSNHL who were treated in our department from 2015 to 2020 (average hearing level at 250-4000 Hz ≥ 40 dB; time from onset to treatment ≤ 14 days; 126 males/109 females; age range 17-87 years (average 61.0 years)). All patients received systemic prednisolone administration combined with intratympanic dexamethasone injection. The pure-tone hearing threshold of 125-8000 Hz was measured at every octave before (HLpre) and after (HLpost) treatment. A multiple regression model was constructed for HLpost (dependent variable) using five explanatory variables (age, days from onset to treatment, presence of vertigo, HLpre, and hearing level of the contralateral ear). RESULTS: The multiple correlation coefficient increased as the frequency increased. Strong correlations were seen in high frequencies, with multiple correlation coefficients of 0.784/0.830 for 4000/8000 Hz. The width of the 70% prediction interval was narrower for 4000/8000 Hz (± 18.2/16.3 dB) than for low to mid-frequencies. Among the five explanatory variables, HLpre showed the largest partial correlation coefficient for any frequency. The partial correlation coefficient for HLpre increased as the frequency increased, which may partially explain the high multiple correlation coefficients for high frequencies. CONCLUSION: The present model would be of practical use for predicting hearing outcomes in high frequencies in patients with ISSNHL.


Asunto(s)
Pérdida Auditiva Sensorineural , Pérdida Auditiva Súbita , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Audiometría de Tonos Puros , Dexametasona , Femenino , Glucocorticoides/uso terapéutico , Audición , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Pérdida Auditiva Súbita/diagnóstico , Pérdida Auditiva Súbita/tratamiento farmacológico , Humanos , Inyección Intratimpánica , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
10.
Nano Lett ; 21(22): 9526-9533, 2021 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-34751025

RESUMEN

Drebrin E is a regulatory protein of intracellular force produced by actomyosin complexes, that is, myosin molecular motors interacting with actin filaments. The expression level of drebrin E in nerve cells decreases as the animal grows, suggesting its pivotal but unclarified role in neuronal development. Here, by applying the microscopic heat pulse method to actomyosin motility assay, the regulatory mechanism is examined from the room temperature up to 37 °C without a thermal denaturing of proteins. We show that the inhibition of actomyosin motility by drebrin E is eliminated immediately and reversibly during heating and depends on drebrin E concentration. The direct observation of quantum dot-labeled drebrin E implies its stable binding to actin filaments during the heat-induced sliding. Our results suggest that drebrin E allosterically modifies the actin filament structure to regulate cooperatively the actomyosin activity at the maintained in vivo body temperature.


Asunto(s)
Actinas , Neuropéptidos , Animales , Miosinas/metabolismo , Neuropéptidos/química , Neuropéptidos/metabolismo , Temperatura
11.
Dev Dyn ; 250(5): 629-639, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33341996

RESUMEN

BACKGROUND: Mechanical homeostasis promotes proper aortic structure and function. Pathological conditions may arise, in part, from compromised or lost homeostasis. There is thus a need to quantify the homeostatic state and when it emerges. Here we quantify changes in mechanical loading, geometry, structure, and function of the murine aorta from the late prenatal period into maturity. RESULTS: Our data suggest that a homeostatic set-point is established by postnatal day P2 for the flow-induced shear stress experienced by endothelial cells; this value deviates from its set-point from P10 to P21 due to asynchronous changes in mechanical loading (flow, pressure) and geometry (radius, wall thickness), but is restored thereafter consistent with homeostasis. Smooth muscle contractility also decreases during this period of heightened matrix deposition but is also restored in maturity. The pressure-induced mechanical stress experienced by intramural cells initially remains low despite increasing blood pressure, and then increases while extracellular matrix accumulates. CONCLUSIONS: These findings suggest that cell-level mechanical homeostasis emerges soon after birth to allow mechanosensitive cells to guide aortic development, with deposition of matrix after P2 increasingly stress shielding intramural cells. The associated tissue-level set-points that emerge for intramural stress can be used to assess and model the aorta that matures biomechanically by P56.


Asunto(s)
Adaptación Biológica , Aorta Torácica/crecimiento & desarrollo , Animales , Homeostasis , Masculino , Ratones Endogámicos C57BL , Estrés Mecánico
12.
Ann Surg Oncol ; 28(9): 5373-5381, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33452606

RESUMEN

BACKGROUND: A previous study conducted a transcriptome analysis of paired normal and esophageal squamous cell carcinoma (ESCC) tissue samples. The results showed that the expression of serine protease 27 (PRSS27) was perturbed in tumor samples. Hence, this retrospective study aimed to validate the prognostic significance of PRSS27 in patients with preoperative treatment for ESCC. METHODS: We enrolled 86 patients who received preoperative treatment before esophagectomy for ESCC. The expression of PRSS27 in resected ESCC and biopsy tissue samples obtained before preoperative treatment was evaluated via immunostaining, and its relationship with clinicopathological features and prognosis was analyzed. RESULTS: In normal esophageal mucosa tissue samples, PRSS27 was expressed in the cytoplasm of spinous cells in the suprabasal layer and basal cells in the basal layer. Of 64 resected ESCC tissue samples, 35 (54.7%) expressed PRSS27 and 29 (45.3%) did not. Moreover, ectopic nuclear expression of PRSS27 was observed. Based on multivariate analysis, PRSS27 expression in resected tumor samples was a predictor of poor prognosis. In cases in which PRSS27 expression was observed in biopsy samples, patients with PRSS27-negative resected tumors had a better postoperative prognosis than those with PRSS27-positive resected tumors. CONCLUSIONS: PRSS27 expression in resected ESCC tissue samples is a poor prognostic factor in ESCC patients with preoperative treatment. Furthermore, conversion of PRSS27 expression from positive in biopsy samples to negative in resected tumor samples is a predictor of good prognosis in these patients. Hence, PRSS27 status is an effective tool for decision making regarding adjuvant treatment in ESCC patients.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias de Cabeza y Cuello , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas de Esófago/terapia , Humanos , Pronóstico , Estudios Retrospectivos , Serina Endopeptidasas , Serina Proteasas
13.
Carcinogenesis ; 41(7): 875-886, 2020 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-31738399

RESUMEN

Glutathione S-transferase omega 2 (GSTO2), which belongs to the superfamily of GST omega class, lacks any appreciable GST activity. Although GSTO2 exhibits thioltransferase and glutathione dehydrogenase activities, its precise expression and physiological functions are still unclear. In the present study, we found that GSTO2 is exclusively expressed in the basal cell layer in Ki67-negative non-proliferative cells in the human esophageal mucosa. GSTO2 overexpression in esophageal squamous cell carcinoma (ESCC) cell lines inhibited cell growth and colony formation, and GSTO2-transfected cells formed smaller tumors in nude mice compared with mock-transfected cells. Interestingly, GSTO2 induction suppressed the expressions of E-cadherin and ß-catenin at the cell-cell contact site. We quantified the phosphorylation levels of key proteins of MAPK signaling pathway and identified phosphorylation of p38. Additionally, HSP27, a downstream molecule of p38, was accelerated in GSTO2-transfected cells, unlike in mock-transfected cells. When GSTO2-transfected cells were treated with a p38 inhibitor, the expression of ß-catenin and the membrane localization of E-cadherin was recovered. We next examined GSTO2 expression in 61 ESCC tissues using quantitative reverse transcription polymerase chain reaction and immunostaining. The results showed that GSTO2 mRNA and protein were significantly reduced in ESCC compared with normal tissues. When human ESCC cell lines were treated with 5-aza-2'-deoxycytidine, a DNA-methyltransferase inhibitor, GSTO2 transcription was induced, suggesting that aberrant hypermethylation is the cause of the down-regulated expression. Our results indicate that GSTO2 expression inhibits the membrane localization of E-cadherin, probably by modulation of the p38 signaling pathway. Down-regulation of GSTO2 by DNA hypermethylation contributes to the growth and progression of ESCC.


Asunto(s)
Cadherinas/genética , Carcinoma de Células Escamosas de Esófago/genética , Glutatión Transferasa/genética , beta Catenina/genética , Animales , Línea Celular Tumoral , Proliferación Celular/genética , Metilación de ADN/genética , Carcinoma de Células Escamosas de Esófago/patología , Regulación Neoplásica de la Expresión Génica/genética , Xenoinjertos , Humanos , Ratones , Transducción de Señal/genética
15.
Gut ; 67(2): 362-371, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-27789659

RESUMEN

OBJECTIVE: The clinical significance of polymorphisms in the interleukin-28B gene encoding interferon (IFN)-λ3, which has antiviral effects, is known in chronic HCV but not in HBV infection. Thus, we measured IFN-λ3 levels in patients with HBV and investigated its clinical significance and association with nucleos(t)ide (NUC) analogue administration. DESIGN: Serum IFN-λ3 level was measured in 254 patients with HBV with varying clinical conditions using our own high sensitivity method. The resulting values were compared with various clinical variables. In addition, cell lines originating from various organs were cultured with NUCs, and the production of IFN-λ3 was evaluated. RESULTS: Higher serum IFN-λ3 levels were detected in the patients treated with nucleotide analogues (adefovir or tenofovir) compared with those treated with nucleoside analogues (lamivudine or entecavir). There were no other differences in the clinical background between the two groups. A rise in the serum IFN-λ3 levels was observed during additional administration of the nucleotide analogues. In vitro experiments showed that the nucleotide analogues directly and dose-dependently induced IFN-λ3 production only in colon cancer cells. Furthermore, the supernatant from cultured adefovir-treated colon cancer cells significantly induced IFN-stimulated genes (ISGs) and inhibited hepatitis B surface antigen (HBsAg) production in hepatoma cells, as compared with the supernatant from entecavir-treated cells. CONCLUSIONS: We discovered that the nucleotide analogues show an additional pharmacological effect by inducing IFN-λ3 production, which further induces ISGs and results in a reduction of HBsAg production. These findings provide novel insights for HBV treatment and suggest IFN-λ3 induction as a possible target.


Asunto(s)
Antivirales/uso terapéutico , Carcinoma Hepatocelular/sangre , Hepatitis B Crónica/sangre , Hepatitis B Crónica/tratamiento farmacológico , Interleucinas/sangre , Neoplasias Hepáticas/sangre , Adenina/análogos & derivados , Adenina/farmacología , Adenina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/farmacología , Infecciones Asintomáticas , Medios de Cultivo Condicionados/farmacología , ADN Viral/sangre , Femenino , Expresión Génica/efectos de los fármacos , Genotipo , Guanina/análogos & derivados , Guanina/farmacología , Guanina/uso terapéutico , Células HT29 , Células Hep G2 , Antígenos de Superficie de la Hepatitis B/metabolismo , Virus de la Hepatitis B/genética , Humanos , Interferones , Interleucinas/farmacología , Lamivudine/farmacología , Lamivudine/uso terapéutico , Cirrosis Hepática/sangre , Masculino , Persona de Mediana Edad , Organofosfonatos/farmacología , Organofosfonatos/uso terapéutico , Polimorfismo Genético , Proteínas Recombinantes , Tenofovir/farmacología , Tenofovir/uso terapéutico , Regulación hacia Arriba/genética , Adulto Joven
16.
J Immunol ; 197(6): 2269-79, 2016 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-27511731

RESUMEN

ESET/SETDB1, one of the major histone methyltransferases, catalyzes histone 3 lysine 9 (H3K9) trimethylation. ESET is critical for suppressing expression of retroviral elements in embryonic stem cells; however, its role in the immune system is not known. We found that thymocyte-specific deletion of ESET caused impaired T cell development, with CD8 lineage cells being most severely affected. Increased apoptosis of CD8 single-positive cells was observed, and TCR-induced ERK activation was severely inhibited in ESET(-/-) thymocytes. Genome-wide comprehensive analysis of mRNA expression and H3K9 trimethylation revealed that ESET regulates expression of numerous genes in thymocytes. Among them, FcγRIIB, whose signaling can inhibit ERK activation, was strongly and ectopically expressed in ESET(-/-) thymocytes. Indeed, genetic depletion of FcγRIIB in ESET(-/-) thymocytes rescued impaired ERK activation and partially restored defective positive selection in ESET(-/-) mice. Therefore, impaired T cell development in ESET(-/-) mice is partly due to the aberrant expression of FcγRIIB. Collectively, to our knowledge, we identify ESET as the first trimethylated H3K9 histone methyltransferase playing a crucial role in T cell development.


Asunto(s)
Linfocitos T CD8-positivos/fisiología , Regulación de la Expresión Génica , N-Metiltransferasa de Histona-Lisina/metabolismo , Animales , Apoptosis , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Diferenciación Celular/genética , Células Madre Embrionarias/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/inmunología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Genoma , N-Metiltransferasa de Histona-Lisina/deficiencia , Histonas/metabolismo , Lisina/metabolismo , Metilación , Ratones , Regiones Promotoras Genéticas , Receptores de IgG/genética , Receptores de IgG/metabolismo , Timocitos/inmunología , Timocitos/fisiología
17.
J Clin Biochem Nutr ; 61(2): 100-107, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28955126

RESUMEN

Fasting-refeeding in mice induces transient hyperproliferation of colonic epithelial cells, which is dependent on the lactate produced as a metabolite of commensal bacteria. We attempted to manipulate colonic epithelial cell turnover with intermittent fasting to prompt recovery from acute colitis. Acute colitis was induced in C57BL/6 mice by administration of dextran sulfate sodium in the drinking water for 5 days. From day 6, mice were fasted for 36 h and refed normal bait, glucose powder, or lactylated high-amylose starch. On day 9, colon tissues were subjected to analysis of histology and cytokine expression. The effect of lactate on the proliferation of colonocytes was assessed by enema in vivo and primary culture in vitro. Intermittent fasting resulted in restored colonic crypts and less expression of interleukin-1ß and interleukin-17 in the colon than in mice fed ad libitum. Administration of lactate in the colon at refeeding time by enema or by feeding lactylated high-amylose starch increased the number of regenerating crypts. Addition of lactate but not butyrate or acetate supported colony formation of colonocytes in vitro. In conclusion, intermittent fasting in the resolution phase of acute colitis resulted in better recovery of epithelial cells and reduced inflammation.

18.
Immunology ; 147(1): 21-9, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26425820

RESUMEN

Group 2 innate lymphoid cells (ILC2s) produce a significant amount of interleukin-5 (IL-5), which supports eosinophil responses in various tissues; they also produce IL-13, which induces mucus production and contributes to tissue repair or fibrosis. The ILC2s are activated by alarmins, such as IL-33 released from epithelia, macrophages and natural killer T (NKT) cells in response to infection and allergen exposure, leading to epithelial injury. We examined gene expression in lung ILC2s and found that ILC2s expressed Ifngr1, the receptor for interferon-γ (IFN-γ). Interferon-γ severely inhibited IL-5 and IL-13 production by lung and kidney ILC2s. To evaluate the effects in vivo, we used α-galactosylceramide (α-GalCer) to induce NKT cells to produce IL-33 and IFN-γ. Intraperitoneal injection of α-GalCer in mice induced NKT cell activation resulting in IL-5 and IL-13 production by ILC2s. Administration of anti-IFN-γ together with α-GalCer significantly enhanced the production of IL-5 and IL-13 by ILC2s in lung and kidney. Conversely, cytokine production from ILC2s was markedly suppressed after injection of exogenous IL-33 in Il33(-/-) mice pre-treated with α-GalCer. Hence, IFN-γ induced or already present in tissues can impact downstream pleiotropic functions mediated by ILC2s, such as inflammation and tissue repair.


Asunto(s)
Inmunidad Innata/efectos de los fármacos , Interferón gamma/metabolismo , Riñón/metabolismo , Pulmón/metabolismo , Linfocitos/metabolismo , Animales , Células Cultivadas , Galactosilceramidas/farmacología , Interferón gamma/inmunología , Interferón gamma/farmacología , Interleucina-13/inmunología , Interleucina-13/metabolismo , Interleucina-33/deficiencia , Interleucina-33/genética , Interleucina-5/genética , Interleucina-5/inmunología , Interleucina-5/metabolismo , Riñón/citología , Riñón/efectos de los fármacos , Riñón/inmunología , Pulmón/citología , Pulmón/efectos de los fármacos , Pulmón/inmunología , Activación de Linfocitos , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Ratones Endogámicos C57BL , Ratones Transgénicos , Células T Asesinas Naturales/inmunología , Células T Asesinas Naturales/metabolismo , Fenotipo , Receptores de Interferón/agonistas , Receptores de Interferón/genética , Receptores de Interferón/inmunología , Receptor de Interferón gamma
19.
J Neurochem ; 136(2): 258-61, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26485083

RESUMEN

Biomarkers in the cerebrospinal fluid (CSF) are currently regarded as indispensable indicators for accurate differential diagnosis of neurodegenerative disorders. Although high levels of astrocyte-secreted glial fibrillar acidic protein (GFAP) in the CSF of patients with Alzheimer's disease (AD) have been reported, the levels of GFAP in the CSF have not been fully investigated in other neurological disorders that cause dementia, such as dementia with Lewy bodies (DLB) and frontotemporal lobar degeneration (FTLD). In this study, we determined the levels of GFAP in the CSF of healthy control subjects and AD, DLB, and FTLD patients to address two questions: (i) Do the levels of GFAP differ among these disorders? and (ii) Can GFAP be used as a biomarker for the differential diagnosis of these neurodegenerative disorders? The levels of GFAP in AD, DLB, and FTLD patients were significantly higher than those in the healthy control subjects. Although the levels of GFAP were not significantly different between AD and DLB patients, a higher level of GFAP was observed in FTLD patients than in AD and DLB patients. It is concluded that representative neurological disorders causing dementia were associated with higher levels of GFAP in the CSF. We propose the following mechanism concerning the amount of glial fibrillar acidic protein (GFAP) in the cerebrospinal fluid (CSF) in Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and frontotemporal lobar degeneration (FTLD). The increase in the release of GFAP into CSF is considered to reflect the sum of degeneration of astrocytes and astrocytosis. The sum of degeneration and astrocytosis or the GFAP release could be in the order of FTLD > DLB > AD > normal condition.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Degeneración Lobar Frontotemporal/líquido cefalorraquídeo , Proteína Ácida Fibrilar de la Glía/líquido cefalorraquídeo , Enfermedad por Cuerpos de Lewy/líquido cefalorraquídeo , Anciano , Péptidos beta-Amiloides/líquido cefalorraquídeo , Análisis de Varianza , Femenino , Humanos , Masculino , Escala del Estado Mental , Fragmentos de Péptidos/líquido cefalorraquídeo , Proteínas tau/líquido cefalorraquídeo
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