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1.
Expert Rev Mol Med ; 26: e16, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557638

RESUMEN

Epigenetic modifications, such as DNA methylation, are enzymatically regulated processes that directly impact gene expression patterns. In early life, they are central to developmental programming and have also been implicated in regulating inflammatory responses. Research into the role of epigenetics in neonatal health is limited, but there is a growing body of literature related to the role of DNA methylation patterns and diseases of prematurity, such as the intestinal disease necrotizing enterocolitis (NEC). NEC is a severe intestinal inflammatory disease, but the key factors that precede disease development remain to be determined. This knowledge gap has led to a failure to design effective targeted therapies and identify specific biomarkers of disease. Recent literature has identified altered DNA methylation patterns in the stool and intestinal tissue of neonates with NEC. These findings provide the foundation for a new avenue in NEC research. In this review, we will provide a general overview of DNA methylation and then specifically discuss the recent literature related to methylation patterns in neonates with NEC. We will also discuss how DNA methylation is used as a biomarker for other disease states and how, with further research, methylation patterns may serve as potential biomarkers for NEC.


Asunto(s)
Biomarcadores , Metilación de ADN , Enterocolitis Necrotizante , Epigénesis Genética , Enterocolitis Necrotizante/genética , Enterocolitis Necrotizante/metabolismo , Humanos , Recién Nacido , Recien Nacido Prematuro , Animales
2.
IJID Reg ; 11: 100353, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38590627

RESUMEN

Objectives: This study aimed to characterize the epidemiology of scabies and its outbreaks in Japanese households, residential care facilities (RCFs), and hospitals using claims data. Methods: This descriptive epidemiological study was conducted using claims data from eight municipalities in Japan. Scabies cases were identified using a combination of recorded diagnoses and administered medications. The study period was from April 2015 to March 2019. Outbreaks were defined as ≥2 cases of scabies occurring within a calendar month at a single household, RCF, or hospital. Results: We identified 857 scabies cases for analysis. The annual prevalence of scabies ranged from 40 to 67 per 100,000 beneficiaries. The annual attack rate of scabies was found to be highest in RCFs (21 per 1000 RCFs), followed by hospitals (11 per 1000 hospitals) and households (0.25 per 1000 households). The annual outbreak attack rate was also highest in RCFs (4.0 per 1000 RCFs), followed by hospitals (1.6 per 1000 hospitals) and household (0.027 per household). The patterns of outbreaks varied widely among the RCFs. Conclusions: The study showcases the potential of claims data for detecting infectious disease outbreaks, which could provide valuable insight for the future management and prevention of scabies. Infection control of scabies in RCFs is crucial in aging societies.

4.
J Vis Exp ; (197)2023 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-37590536

RESUMEN

Necrotizing enterocolitis (NEC) is a severe and potentially fatal intestinal disease that has been difficult to study due to its complex pathogenesis, which remains incompletely understood. The pathophysiology of NEC includes disruption of intestinal tight junctions, increased gut barrier permeability, epithelial cell death, microbial dysbiosis, and dysregulated inflammation. Traditional tools to study NEC include animal models, cell lines, and human or mouse intestinal organoids. While studies using those model systems have improved the field's understanding of disease pathophysiology, their ability to recapitulate the complexity of human NEC is limited. An improved in vitro model of NEC using microfluidic technology, named NEC-on-a-chip, has now been developed. The NEC-on-a-chip model consists of a microfluidic device seeded with intestinal enteroids derived from a preterm neonate, co-cultured with human endothelial cells and the microbiome from an infant with severe NEC. This model is a valuable tool for mechanistic studies into the pathophysiology of NEC and a new resource for drug discovery testing for neonatal intestinal diseases. In this manuscript, a detailed description of the NEC-on-a-chip model will be provided.


Asunto(s)
Enterocolitis Necrotizante , Enfermedades del Recién Nacido , Microbiota , Animales , Lactante , Ratones , Humanos , Recién Nacido , Disbiosis , Células Endoteliales , Microfluídica
5.
Int J Cardiol ; 379: 89-95, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-36934988

RESUMEN

BACKGROUND: Early decongestion with diuretics could improve clinical outcomes. This study aimed to examine the impact of the time-to-target rate of urine volume (T2TUV) concept on the outcome of acute decompensated heart failure (ADHF). METHODS: This multicenter retrospective study included 1670 patients with ADHF who received diuretics within 24 h of admission. T2TUV was defined as the time from admission to the rate of urine volume of 100 ml/h. The primary outcomes were in-hospital death, mortality, and re-hospitalization for 1 year. RESULTS: A total of 789 patients met the inclusion criteria (T2TUV on day 1, n = 248; day 2-3, n = 172; no target rate UV, n = 369). In-hospital mortality in the day 1 group was significantly lower (2.7% vs. 5.9% vs. 11.1%; p < 0.001) than that of other groups. The mortality and re-hospitalization for 1 year in the day 1 group was significantly lower (event-free rate: 67.7% vs. 54.1% vs. 56.9%; log-lank p = 0.004) than that of other groups. In multivariate analysis, predictors of T2TUV at day 1 were age (odds ratio [OR]: 1.02, 95% confidence interval [CI]: 1.01-1.04, p = 0.007), previous hospitalized heart failure (OR: 1.47, 95% CI: [1.03-2.12], p = 0.03), N-terminal-pro B type natriuretic peptide per 1000 pg/ml (OR: 1.02, 95% CI: 1.01-1.04, p = 0.007), carperitide (OR: 0.69, 95% CI: 0.48-0.99, p = 0.05), and early administration of tolvaptan (OR: 0.6, 95% CI: 0.42-0.85, p = 0.004). CONCLUSIONS: T2TUV of less than day 1 was associated with lower in-hospital mortality and decreased mortality and re-hospitalization at 1 year.


Asunto(s)
Insuficiencia Cardíaca , Humanos , Estudios Retrospectivos , Mortalidad Hospitalaria , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/complicaciones , Diuréticos , Tolvaptán , Enfermedad Aguda , Péptido Natriurético Encefálico
6.
Am J Cardiovasc Drugs ; 23(2): 185-196, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36739357

RESUMEN

BACKGROUND: Diuretic response (DR) in patients with symptomatic acute decompensated heart failure (ADHF) has an impact on prognosis. This study aimed to identify predictive factors influencing acute 6 h poor DR and to assess DR after early administration of tolvaptan (TLV). METHODS: This multicenter retrospective study included 1670 patients who were admitted for ADHF and received intravenous furosemide within 1 h of presentation in clinical scenario 1 or 2 defined based on initial systolic blood pressure ≥100 mmHg with severe symptoms (New York Heart Association class III or IV (n = 830). The score for the poor DR factors in the very acute phase was calculated in patients treated with furosemide-only diuretics (n = 439). The DR to TLV administration was also assessed in patients who received an additional dose of TLV within 6 h (n = 391). RESULTS: The time since discharge from the hospital for a previous heart failure < 3 months (odds ratio [OR] 2.78, 95% confidence interval [CI] 1.34-5.83; p = 0.006), loop diuretics at admission (OR 3.05, 95% CI 1.74-5.36; p < 0.0001), and estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2 (OR 2.99, 95% CI 1.58-5.74; p = 0.0007) were independent determinants of poor DR. The frequency of poor DR according to the risk stratification group was low risk (no risk factor), 18.9%; middle risk (one risk factor), 33.1%; and high risk (two to three risk factors), 58.0% (p < 0.0001). All risk groups demonstrated a significantly lower incidence of poor DR with early TLV administration: 10.7% in the early TLV group versus 18.9% in the loop diuretics group (p = 0.09) of the low-risk group; 18.4% versus 33.1% (p = 0.01) in the middle-risk group, and 20.2% versus 58.0% (p < 0.0001) in the high-risk group. CONCLUSION: Early administration of TLV in patients with predicted poor DR contributed to a significant diuretic effect and suppression of worsening renal function.


Asunto(s)
Diuréticos , Insuficiencia Cardíaca , Humanos , Tolvaptán/uso terapéutico , Diuréticos/uso terapéutico , Furosemida , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/uso terapéutico , Estudios Retrospectivos , Insuficiencia Cardíaca/tratamiento farmacológico
7.
Br J Nutr ; 128(6): 1050-1063, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34632971

RESUMEN

Necrotising enterocolitis (NEC) is a devastating gastrointestinal disease of prematurity that typically develops after the administration of infant formula, suggesting a link between nutritional components and disease development. One of the most significant complications that develops in patients with NEC is severe lung injury. We have previously shown that the administration of a nutritional formula that is enriched in pre-digested Triacylglyceride that do not require lipase action can significantly reduce the severity of NEC in a mouse model. We now hypothesise that this 'pre-digested fat (PDF) system' may reduce NEC-associated lung injury. In support of this hypothesis, we now show that rearing newborn mice on a nutritional formula based on the 'PDF system' promotes lung development, as evidenced by increased tight junctions and surfactant protein expression. Mice that were administered this 'PDF system' were significantly less vulnerable to the development of NEC-induced lung inflammation, and the administration of the 'PDF system' conferred lung protection. In seeking to define the mechanisms involved, the administration of the 'PDF system' significantly enhanced lung maturation and reduced the production of reactive oxygen species (ROS). These findings suggest that the PDF system protects the development of NEC-induced lung injury through effects on lung maturation and reduced ROS in the lung and also increases lung maturation in non-NEC mice.


Asunto(s)
Enterocolitis Necrotizante , Lesión Pulmonar , Animales , Ratones , Enterocolitis Necrotizante/etiología , Animales Recién Nacidos , Especies Reactivas de Oxígeno , Lesión Pulmonar/complicaciones , Lesión Pulmonar/metabolismo , Alimentos Formulados , Modelos Animales de Enfermedad
8.
Sci Transl Med ; 13(612): eabg3459, 2021 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-34550727

RESUMEN

Necrotizing enterocolitis (NEC) is a devastating disease of premature infants, whose pathogenesis remains incompletely understood, although activation of the Gram-negative bacterial receptor Toll-like receptor 4 (TLR4) on the intestinal epithelium plays a critical role. Patients with NEC typically display gastrointestinal dysmotility before systemic disease is manifest, suggesting that dysmotility could drive NEC development. Both intestinal motility and inflammation are governed by the enteric nervous system, a network of enteric neurons and glia. We hypothesized here that enteric glia loss in the premature intestine could lead to dysmotility, exaggerated TLR4 signaling, and NEC development. We found that intestinal motility is reduced early in NEC in mice, preceding the onset of intestinal inflammation, whereas pharmacologic restoration of intestinal motility reduced NEC severity. Ileal samples from mouse, piglet, and human NEC revealed enteric glia depletion, and glia-deficient mice (Plp1ΔDTR, Sox10ΔDTR, and BdnfΔDTR) showed increased NEC severity compared with wild-type mice. Mice lacking TLR4 on enteric glia (Sox10-Tlr4ko) did not show NEC-induced enteric glia depletion and were protected from NEC. Mechanistically, brain-derived neurotrophic factor (BDNF) from enteric glia restrained TLR4 signaling on the intestine to prevent NEC. BDNF was reduced in mouse and human NEC, and BDNF administration reduced both TLR4 signaling and NEC severity in enteric glia­deficient mice. Last, we identified an agent (J11) that enhanced enteric glial BDNF release, inhibited intestinal TLR4, restored motility, and prevented NEC in mice. Thus, enteric glia loss might contribute to NEC through intestinal dysmotility and increased TLR4 activation, suggesting enteric glia therapies for this disorder.


Asunto(s)
Enterocolitis Necrotizante , Receptor Toll-Like 4 , Humanos , Recién Nacido , Neuroglía , Receptor Toll-Like 4/genética , Animales , Ratones
10.
Nat Commun ; 12(1): 1042, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33589625

RESUMEN

Necrotizing enterocolitis (NEC) is a disease of premature infants characterized by acute intestinal necrosis. Current dogma suggests that NEC develops in response to post-natal dietary and bacterial factors, and so a potential role for in utero factors in NEC remains unexplored. We now show that during pregnancy, administration of a diet rich in the aryl hydrocarbon receptor (AHR) ligand indole-3-carbinole (I3C), or of breast milk, activates AHR and prevents NEC in newborn mice by reducing Toll-like receptor 4 (TLR4) signaling in the newborn gut. Protection from NEC requires activation of AHR in the intestinal epithelium which is reduced in mouse and human NEC, and is independent of leukocyte activation. Finally, we identify an AHR ligand ("A18") that limits TLR4 signaling in mouse and human intestine, and prevents NEC in mice when administered during pregnancy. In summary, AHR signaling is critical in NEC development, and maternally-delivered, AHR-based therapies may alleviate NEC.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Enterocolitis Necrotizante/genética , Indoles/administración & dosificación , Leche Humana/fisiología , Receptores de Hidrocarburo de Aril/genética , Receptor Toll-Like 4/genética , Animales , Animales Recién Nacidos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/agonistas , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/inmunología , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/inmunología , Dieta/métodos , Modelos Animales de Enfermedad , Enterocolitis Necrotizante/inmunología , Enterocolitis Necrotizante/patología , Enterocolitis Necrotizante/prevención & control , Femenino , Regulación de la Expresión Génica , Humanos , Recién Nacido , Recien Nacido Prematuro , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Ligandos , Exposición Materna , Ratones , Embarazo , Receptores de Hidrocarburo de Aril/agonistas , Receptores de Hidrocarburo de Aril/inmunología , Transducción de Señal , Porcinos , Receptor Toll-Like 4/inmunología
11.
Micromachines (Basel) ; 12(2)2021 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-33498919

RESUMEN

Many applications in biotechnology and medicine, among other disciplines, require the rapid enumeration of bacteria, preferably using miniaturized portable devices. Microfluidic technology is expected to solve this miniaturization issue. In the enumeration of bacteria in microfluidic devices, the technique of aligning bacteria in a single line prior to counting is the key to an accurate count at single-bacterium resolution. Here, we describe the numerical and experimental evaluation of a device utilizing a dielectrophoretic force to array bacteria in a single line, allowing their facile numeration. The device comprises a channel to flow bacteria, two counter electrodes, and a capture electrode several microns or less in width for arranging bacteria in a single line. When the capture electrode is narrower than the diameter of a bacterium, the entrapment efficiency of the one-dimensional array is 80% or more within 2 s. Furthermore, since some cell-sorting applications require bacteria to move against the liquid flow, we demonstrated that bacteria can move in a single line in the off-axial direction tilted 30° from the flow direction. Our findings provide the basis for designing miniature, portable devices for evaluating bacteria with single-cell accuracy.

12.
Sci Transl Med ; 13(575)2021 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-33408187

RESUMEN

Necrotizing enterocolitis (NEC) causes acute intestinal necrosis in premature infants and is associated with severe neurological impairment. In NEC, Toll-like receptor 4 is activated in the intestinal epithelium, and NEC-associated brain injury is characterized by microglial activation and white matter loss through mechanisms that remain unclear. We now show that the brains of mice and humans with NEC contained CD4+ T lymphocytes that were required for the development of brain injury. Inhibition of T lymphocyte influx into the brains of neonatal mice with NEC reduced inflammation and prevented myelin loss. Adoptive intracerebroventricular delivery of gut T lymphocytes from mice with NEC into Rag1 -/- recipient mice lacking CD4+ T cells resulted in brain injury. Brain organoids derived from mice with or without NEC and from human neuronal progenitor cells revealed that IFN-γ release by CD4+ T lymphocytes induced microglial activation and myelin loss in the organoids. IFN-γ knockdown in CD4+ T cells derived from mice with NEC abrogated the induction of NEC-associated brain injury after adoptive transfer to naïve Rag1 -/- recipient mice. T cell receptor sequencing revealed that NEC mouse brain-derived T lymphocytes shared homology with gut T lymphocytes from NEC mice. Intraperitoneal injection of NEC gut-derived CD4+ T lymphocytes into naïve Rag1 -/- recipient mice induced brain injury, suggesting that gut-derived T lymphocytes could mediate neuroinflammation in NEC. These findings indicate that NEC-associated brain injury may be induced by gut-derived IFN-γ-releasing CD4+ T cells, suggesting that early management of intestinal inflammation in children with NEC could improve neurological outcomes.


Asunto(s)
Enterocolitis Necrotizante , Animales , Encéfalo , Inflamación , Mucosa Intestinal , Ratones , Linfocitos T Reguladores
15.
Pediatr Res ; 89(1): 91-101, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32221473

RESUMEN

BACKGROUND: Necrotizing enterocolitis (NEC) develops through exaggerated toll-like receptor 4 (TLR4) signaling in the intestinal epithelium. Breast milk is rich in non-digestible oligosaccharides and prevents NEC through unclear mechanisms. We now hypothesize that the human milk oligosaccharides 2'-fucosyllactose (2'-FL) and 6'-sialyllactose (6'-SL) can reduce NEC through inhibition of TLR4 signaling. METHODS: NEC was induced in newborn mice and premature piglets and infant formula was supplemented with 2'-FL, 6'-SL, or lactose. Intestinal tissue was obtained at surgical resection. HMO inhibition of TLR4 was assessed in IEC-6 enterocytes, mice, and human tissue explants and via in silico modeling. RESULTS: Supplementation of infant formula with either 2'-FL and/or 6'-SL, but not the parent sugar lactose, reduced NEC in mice and piglets via reduced apoptosis, inflammation, weight loss, and histological appearance. Mechanistically, both 2'-FL and 6'-SL, but not lactose, reduced TLR4-mediated nuclear factor kappa light-chain enhancer of activated B cells (NF-kB) inflammatory signaling in the mouse and human intestine. Strikingly, in silico modeling revealed 2'-FL and 6'-SL, but not lactose, to dock into the binding pocket of the TLR4-MD2 complex, explaining their ability to inhibit TLR4 signaling. CONCLUSIONS: 2'-FL and 6'-SL, but not lactose, prevent NEC in mice and piglet models and attenuate NEC inflammation in the human ileum, in part through TLR4 inhibition. IMPACT: Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in premature infants that occurs in the setting of bacterial colonization of the gut and administration of formula feeds and activation by the innate immune receptor toll-like receptor 4 (TLR4). Breast milk prevents NEC through unclear mechanisms. We now show that breast milk-enriched human milk oligosaccharides (HMOs) that are derived from lactose prevent NEC through inhibition of TLR4. The human milk oligosaccharides 2'-FL and 6'-SL, but not the backbone sugar lactose, prevent NEC in mice and piglets. 2'-FL and 6'-SL but not lactose inhibited TLR4 signaling in cultured enterocytes, in enteroids derived from mouse intestine, and in human intestinal explants obtained at the time of surgical resection for patients with NEC. In seeking the mechanisms involved, 2'-FL and 6'-SL but not lactose were found to directly bind to TLR4, explaining the inhibition and protection against NEC. These findings may impact clinical practice by suggesting that administration of HMOs could serve as a preventive strategy for premature infants at risk for NEC development.


Asunto(s)
Enterocolitis Necrotizante/prevención & control , Íleon/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Lactosa/análogos & derivados , Leche Humana/química , Receptor Toll-Like 4/antagonistas & inhibidores , Trisacáridos/farmacología , Animales , Animales Recién Nacidos , Apoptosis/efectos de los fármacos , Línea Celular , Modelos Animales de Enfermedad , Enterocolitis Necrotizante/inmunología , Enterocolitis Necrotizante/metabolismo , Enterocolitis Necrotizante/patología , Humanos , Íleon/inmunología , Íleon/metabolismo , Íleon/patología , Mediadores de Inflamación/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Lactosa/aislamiento & purificación , Lactosa/farmacología , Ratones , Simulación del Acoplamiento Molecular , Transducción de Señal , Sus scrofa , Receptor Toll-Like 4/metabolismo , Trisacáridos/aislamiento & purificación , Pérdida de Peso/efectos de los fármacos
16.
Int J Infect Dis ; 96: 343-347, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32376307

RESUMEN

OBJECTIVES: Given that the optimal antibiotic treatment duration for acute cholangitis with successful biliary drainage remains unknown, this study aimed to validate whether antibiotic treatment duration could be reduced to ≤3 days among patients presenting the same. METHODS: This retrospective study included patients who presented with mild to moderate acute cholangitis due to choledocholithiasis who had undergone successful biliary drainage through endoscopic retrograde cholangiopancreatography (ERCP). After that, 30-day mortality rates and 3-month recurrence rates following short-course antibiotic treatment (SCT, ≤3 days) and long-course antibiotic treatment (LCT, ≥4 days) were compared. RESULTS: A total of 96 patients were analyzed, among whom 22 (22.9%) received SCT, and 74 (77.1%) received LCT. The SCT and LCT groups had a median antibiotic treatment duration of 1.5 (range 1-3) and seven (range 4-17) days, respectively. Moreover, the SCT and LCT groups exhibited no significant differences in cholangitis grades, 30-day mortality rates (0%, 0/22 and 2.7%, 2/74, respectively), 3-month recurrence rates, length of hospitalization, and acute bacteremic cholangitis rates. CONCLUSIONS: This study suggests that antibiotic treatment for ≤3 days may be adequate for patients with mild to moderate acute cholangitis due to choledocholithiasis who had undergone successful biliary drainage.


Asunto(s)
Antibacterianos/uso terapéutico , Colangitis/tratamiento farmacológico , Coledocolitiasis/complicaciones , Enfermedad Aguda/terapia , Anciano , Anciano de 80 o más Años , Bacteriemia/tratamiento farmacológico , Bacteriemia/etiología , Bacteriemia/terapia , Conductos Biliares/cirugía , Colangiopancreatografia Retrógrada Endoscópica , Colangitis/etiología , Colangitis/terapia , Drenaje , Femenino , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
17.
Cell Mol Gastroenterol Hepatol ; 9(3): 403-423, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31756560

RESUMEN

BACKGROUND & AIMS: Necrotizing enterocolitis (NEC) is a devastating disease of premature infants characterized by Toll-like receptor 4 (TLR4)-dependent intestinal inflammation and enterocyte death. Given that necroptosis is a proinflammatory cell death process that is linked to bacterial signaling, we investigated its potential role in NEC, and the mechanisms involved. METHODS: Human and mouse NEC intestine were analyzed for necroptosis gene expression (ie, RIPK1, RIPK3, and MLKL), and protein activation (phosphorylated RIPK3). To evaluate a potential role for necroptosis in NEC, the effects of genetic (ie, Ripk3 knockout or Mlkl knockout) or pharmacologic (ie, Nec1s) inhibition of intestinal inflammation were assessed in a mouse NEC model, and a possible upstream role of TLR4 was assessed in Tlr4-deficient mice. The NEC-protective effects of human breast milk and its constituent milk oligosaccharides on necroptosis were assessed in a NEC-in-a-dish model, in which mouse intestinal organoids were cultured as either undifferentiated or differentiated epithelium in the presence of NEC bacteria and hypoxia. RESULTS: Necroptosis was activated in the intestines of human and mouse NEC in a TLR4-dependent manner, and was up-regulated specifically in differentiated epithelium of the immature ileum. Inhibition of necroptosis genetically and pharmacologically reduced intestinal-epithelial cell death and mucosal inflammation in experimental NEC, and ex vivo in the NEC-in-a-dish system. Strikingly, the addition of human breast milk, or the human milk oligosaccharide 2 fucosyllactose in the ex vivo system, reduced necroptosis and inflammation. CONCLUSIONS: Necroptosis is activated in the intestinal epithelium upon TLR4 signaling and is required for NEC development, and explains in part the protective effects of breast milk.


Asunto(s)
Enterocolitis Necrotizante/patología , Enterocitos/patología , Mucosa Intestinal/patología , Leche Humana/química , Necroptosis/inmunología , Animales , Modelos Animales de Enfermedad , Enterocolitis Necrotizante/tratamiento farmacológico , Enterocolitis Necrotizante/genética , Enterocolitis Necrotizante/inmunología , Enterocitos/efectos de los fármacos , Enterocitos/inmunología , Femenino , Humanos , Recién Nacido , Mucosa Intestinal/efectos de los fármacos , Ratones , Ratones Noqueados , Necroptosis/efectos de los fármacos , Proteínas Quinasas/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transducción de Señal/inmunología , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Trisacáridos/farmacología , Trisacáridos/uso terapéutico , Regulación hacia Arriba
18.
J Immunol ; 203(11): 3000-3012, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31645418

RESUMEN

Angiotensin-converting enzyme 2 (ACE2) is a potent negative regulator capable of restraining overactivation of the renin-angiotensin system, which contributes to exuberant inflammation after bacterial infection. However, the mechanism through which ACE2 modulates this inflammatory response is not well understood. Accumulating evidence indicates that infectious insults perturb ACE2 activity, allowing for uncontrolled inflammation. In the current study, we demonstrate that pulmonary ACE2 levels are dynamically varied during bacterial lung infection, and the fluctuation is critical in determining the severity of bacterial pneumonia. Specifically, we found that a pre-existing and persistent deficiency of active ACE2 led to excessive neutrophil accumulation in mouse lungs subjected to bacterial infection, resulting in a hyperinflammatory response and lung damage. In contrast, pre-existing and persistent increased ACE2 activity reduces neutrophil infiltration and compromises host defense, leading to overwhelming bacterial infection. Further, we found that the interruption of pulmonary ACE2 restitution in the model of bacterial lung infection delays the recovery process from neutrophilic lung inflammation. We observed the beneficial effects of recombinant ACE2 when administered to bacterially infected mouse lungs following an initial inflammatory response. In seeking to elucidate the mechanisms involved, we discovered that ACE2 inhibits neutrophil infiltration and lung inflammation by limiting IL-17 signaling by reducing the activity of the STAT3 pathway. The results suggest that the alteration of active ACE2 is not only a consequence of bacterial lung infection but also a critical component of host defense through modulation of the innate immune response to bacterial lung infection by regulating neutrophil influx.


Asunto(s)
Inflamación/inmunología , Neutrófilos/inmunología , Peptidil-Dipeptidasa A/inmunología , Infecciones por Pseudomonas/inmunología , Pseudomonas aeruginosa/inmunología , Enzima Convertidora de Angiotensina 2 , Animales , Modelos Animales de Enfermedad , Femenino , Imidazoles/administración & dosificación , Imidazoles/farmacología , Inmunidad Innata/efectos de los fármacos , Inmunidad Innata/inmunología , Inflamación/tratamiento farmacológico , Inflamación/patología , Leucina/administración & dosificación , Leucina/análogos & derivados , Leucina/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Pruebas de Sensibilidad Microbiana , Neutrófilos/efectos de los fármacos , Neutrófilos/patología , Peptidil-Dipeptidasa A/deficiencia , Peptidil-Dipeptidasa A/genética , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/patología , Pseudomonas aeruginosa/efectos de los fármacos
19.
J Clin Microbiol ; 57(11)2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31434721

RESUMEN

Although hypervirulent Klebsiella pneumoniae (hvKp) has been associated with severe community-acquired infections that occur among relatively healthy individuals, information about hvKp infections in health care settings remains limited. Here, we systematically analyzed the clinical and molecular characteristics of K. pneumoniae isolates causing bloodstream infections in a cross-sectional study. Clinical characteristics of K. pneumoniae bloodstream infections from hospitals across Japan were analyzed by a review of the medical records. Whole-genome sequencing of the causative isolates was performed. Bacterial species were confirmed and hvKp were identified using whole-genome sequencing data. Clinical characteristics of hvKp infections were compared with those of non-hvKp infections by bivariate analyses. Of 140 cases of K. pneumoniae bloodstream infections, 26 cases (18.6%) were caused by various clones of hvKp defined by the carriage of cardinal virulence genes. Molecular identification revealed that 24 (17.1%) and 14 (10%) cases were caused by Klebsiella variicola and Klebsiella quasipneumoniae, respectively. Patients with hvKp infections had higher proportions of diabetes mellitus (risk ratio [RR], 1.75; 95% confidence interval [CI], 1.05 to 2.94), and their infections had significantly higher propensity to involve pneumonia (RR, 5.85; 95% CI, 1.39 to 24.6), liver abscess (RR, 5.85; 95% CI, 1.39 to 24.6), and disseminated infections (RR, 6.58; 95% CI, 1.16 to 37.4) than infections by other isolates. More than one-half of hvKp infections were health care associated or hospital acquired, and a probable event of health care-associated transmission of hvKp was documented. hvKp isolates, which are significantly associated with severe and disseminated infections, are frequently involved in health care-associated and hospital-acquired infections in Japan.


Asunto(s)
Bacteriemia/microbiología , Infección Hospitalaria/microbiología , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidad , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/epidemiología , Infección Hospitalaria/epidemiología , Estudios Transversales , Femenino , Genoma Bacteriano , Hospitales/estadística & datos numéricos , Humanos , Japón , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Masculino , Virulencia/genética , Secuenciación Completa del Genoma , beta-Lactamasas/genética
20.
Shock ; 52(2): 215-223, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30148762

RESUMEN

Necrotizing enterocolitis (NEC) is the leading cause of death from gastrointestinal disease in premature infants, and is associated with the development of severe lung inflammation. The pathogenesis of NEC-induced lung injury remains unknown, yet infiltrating immune cells may play a role. In support of this possibility, we now show that NEC in mice and humans was associated with the development of profound lung injury that was characterized by an influx of Th17 cells and a reduction in T regulatory lymphocytes (Tregs). Importantly, the adoptive transfer of CD4 T cells isolated from lungs of mice with NEC into the lungs of immune incompetent mice (Rag1 mice) induced profound inflammation in the lung, while the depletion of Tregs exacerbated NEC induced lung injury, demonstrating that imbalance of Th17/Treg in the lung is required for the induction of injury. In seeking to define the mechanisms involved, the selective deletion of toll-like receptor 4 (TLR4) from the Sftpc1 pulmonary epithelial cells reversed lung injury, while TLR4 activation induced the Th17 recruiting chemokine (C-C motif) ligand 25 (CCL25) in the lungs of mice with NEC. Strikingly, the aerosolized inhibition of both CCL25 and TLR4 and the administration of all trans retinoic acid restored Tregs attenuated NEC-induced lung injury. In summary, we show that TLR4 activation in Surfactant protein C-1 (Sftpc1) cells disrupts the Treg/Th17 balance in the lung via CCL25 leading to lung injury after NEC and reveal that inhibition of TLR4 and stabilization of Th17/Treg balance in the neonatal lung may prevent this devastating complication of NEC.


Asunto(s)
Lesión Pulmonar/metabolismo , Linfocitos/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Células Cultivadas , Quimiocinas CC/metabolismo , Enterocolitis/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Inmunohistoquímica , Interleucina-17/metabolismo , Ratones , Ratones Endogámicos C57BL , Linfocitos T Reguladores/metabolismo
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