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1.
Am J Physiol Cell Physiol ; 326(1): C304-C316, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38047305

RESUMO

It is known that pulmonary vascular leakage, a key pathological feature of sepsis-induced lung injury, is largely regulated by perivascular cells. However, the underlying mechanisms have not been fully uncovered. In the present study, we aimed to evaluate the role of isthmin1, a secretory protein originating from alveolar epithelium, in the pulmonary vascular leakage during sepsis and to investigate the regulatory mechanisms of isthmin1 gene transcription. We observed an elevated isthmin1 gene expression in the pulmonary tissue of septic mice induced by cecal ligation and puncture (CLP), as well as in primary murine alveolar type II epithelial cells (ATII) exposed to lipopolysaccharide (LPS). Furthermore, we confirmed that isthmin1 derived from ATII contributes to pulmonary vascular leakage during sepsis. Specifically, adenovirus-mediated isthmin1 disruption in ATII led to a significant attenuation of the increased pulmonary microvascular endothelial cell (PMVEC) hyperpermeability in a PMVEC/ATII coculture system when exposed to LPS. In addition, adeno-associated virus 9 (AAV9)-mediated knockdown of isthmin1 in the alveolar epithelium of septic mice significantly attenuated pulmonary vascular leakage. Finally, mechanistic studies unveiled that nuclear transcription factor CCAAT/enhancer binding protein (C/EBP)ß participates in isthmin1 gene activation by binding directly to the cis-regulatory element of isthmin1 locus and may contribute to isthmin1 upregulation during sepsis. Collectively, the present study highlighted the impact of the paracrine protein isthmin1, derived from ATII, on the exacerbation of pulmonary vascular permeability in sepsis and revealed a new regulatory mechanism for isthmin1 gene transcription.NEW & NOTEWORTHY This article addresses the role of the alveolar epithelial-secreted protein isthmin1 on the exacerbation of pulmonary vascular permeability in sepsis and identified nuclear factor CCAAT/enhancer binding protein (C/EBP)ß as a new regulator of isthmin1 gene transcription. Targeting the C/EBPß-isthmin1 regulatory axis on the alveolar side would be of great value in the treatment of pulmonary vascular leakage and lung injury induced by sepsis.


Assuntos
Lesão Pulmonar , Sepse , Animais , Camundongos , Permeabilidade Capilar/fisiologia , Técnicas de Cocultura , Lipopolissacarídeos/toxicidade , Pulmão/metabolismo , Lesão Pulmonar/genética , Sepse/patologia , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo
2.
Ann Surg Oncol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888859

RESUMO

OBJECTIVE: The purpose of this study was to assess 10-year follow-up outcomes after surgical resection in patients with stage IA invasive non-small cell lung cancer (NSCLC) based on postoperative pathological diagnosis. METHODS: Patients with stage IA invasive NSCLC who underwent resection between December 2008 and December 2013 were reviewed. Patients were categorized into the pure-ground glass opacity (pGGO), mixed-ground glass opacity (mGGO), and solid groups based on consolidation to tumor ratio (CTR). Postoperative survival and risk of recurrence and developing secondary primary lung cancer were analyzed in each group. RESULTS: Among the 645 stage IA invasive NSCLC, the 10-year overall survival and recurrence-free survival rate was 79.38% and 77.44%, respectively. The 10-year overall survival for pGGO, mGGO, and solid group of patients was 95.08%, 86.21%, and 72.39%, respectively. The respective recurrence-free survival rate was 100%, 89.82%, and 65.83%. Multivariable Cox regression analysis associated tumor size and GGO components with recurrence and younger age, and tumors with GGO components were associated with longer overall survival. The cumulative incidence curve indicated no recurrence of GGO lung cancer ≥ 5 years postoperatively. Our cohort indicated that the number and stations of dissected lymph node did not influence long-term prognosis of IA invasive NSCLC. CONCLUSIONS: Recurrence of invasive stage IA NSCLC with GGO was more prevalent in patients with tumor size >1 cm and CTR > 0.5, occurring within 5 years after surgery. This will provide important evidence for follow-up strategies in these patients.

3.
Cryobiology ; 113: 104563, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37532122

RESUMO

Acute extreme cold exposure impairs human health and even causes hypothermia which threatens human life. Liver, as a hub in metabolism and thermogenesis, is vital for cold acclimatization. Although accumulating evidence has suggested that cold exposure can cause liver damage, the underlying mechanisms remain poorly understood. This study investigated the role and underlying mechanisms of ferroptosis in cold stress-induced liver damage. To evaluate the role of ferroptosis in cold stress-induced liver damage, rats were pretreated with ferroptosis inhibitor liproxstatin-1 (Lip-1) before exposed to -10 °C for 8 h. Core body temperature was recorded. The levels of ferroptosis-related indicators were examined with the corresponding assay kits or by western blotting. Hepatic pathological changes were analyzed by hematoxylin-eosin staining and ultrastructural observation. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were measured to assess liver function. Rats were also pretreated with p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 or Dynamin-related protein 1 (Drp1) inhibitor Mdivi-1 to determine the underlying mechanisms. We found that Lip-1 inhibited ferroptosis, attenuated hepatic pathological damages and blocked the increased ALT and AST levels in cold-exposed rats. Moreover, Mdivi-1 inhibited mitochondrial fission and suppressed ferroptosis. Furthermore, SB203580 and Mdivi-1 administration alleviated cold stress-induced liver injury. Our results suggested that cold stress caused liver damage partially by inducing ferroptosis through the p38 MAPK/Drp1 pathway. These findings might provide an effective preventive and therapeutic target for cold stress-induced liver injury.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Ferroptose , Ratos , Humanos , Animais , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Resposta ao Choque Frio , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Criopreservação/métodos , Dinaminas/genética , Dinaminas/metabolismo , Fígado/metabolismo
4.
Sheng Li Xue Bao ; 75(3): 351-359, 2023 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-37340644

RESUMO

To explore the changes of cold sensitivity after exposure to acute hypoxia and its mechanisms, Sprague-Dawley rats were divided into normoxia control group (21% O2, 25 °C), 10% O2 hypoxia group (10% O2, 25 °C), 7% O2 hypoxia group (7% O2, 25 °C), normoxia cold group (21% O2, 10 °C) and hypoxia cold group (7% O2, 10 °C). Cold foot withdrawal latency and preference temperature of each group were measured, skin temperatures were estimated using an infrared thermographic imaging camera, body core temperature was recorded by wireless telemetry system, immunohistochemical staining was used to detect the expression of c-Fos in the lateral parabrachial nucleus (LPB). The results showed that acute hypoxia significantly prolonged the latency of cold foot withdrawal and significantly enhanced the intensity of cold stimulation for foot withdrawal, and the rats under hypoxia preferred cold temperature. Cold exposure (10 °C) for 1 h significantly enhanced the expression of c-Fos in LPB of rats in normoxia, while hypoxia inhibited cold-induced c-Fos expression. Acute hypoxia significantly increased the skin temperature of feet and tails, decreased the skin temperature of interscapular region, and decreased the body core temperature of rats. These results indicate that acute hypoxia can significantly blunt cold sensitivity through the inhibition of LPB, suggesting actively keeping warm measures should be taken at the early stage after ascent to high altitude to prevent the upper respiratory infection and acute mountain sickness.


Assuntos
Núcleos Parabraquiais , Ratos , Animais , Ratos Sprague-Dawley , Núcleos Parabraquiais/fisiologia , Temperatura , Temperatura Baixa , Hipóxia , Proteínas Proto-Oncogênicas c-fos
5.
Am J Physiol Regul Integr Comp Physiol ; 323(5): R822-R831, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36189986

RESUMO

Exercise-induced fatigue is a complex physiological phenomenon and is greatly influenced by central mechanisms in brain. As one of the most abundant circulating carbon metabolites, l-lactate in brain has been considered to be an important supplementary fuel during exercise; however, whether it plays a signaling role in fatigue remains largely obscure. In this study, our results initially revealed that brain l-lactate levels were increased after an exhaustive swimming session in several brain regions including motor cortex, hippocampus, and cerebellum. Then, we examined the specific role of brain lactate receptor, also known as hydroxycarboxylic acid receptor 1 (GPR81), in exercise-induced fatigue. We found that intracerebroventricular injection of either d-lactate (an enantiomer that could mediate activation of GPR81 as l-lactate) or a potent GPR81 agonist 3-chloro-5-hydroxybenzoic acid (CHBA), significantly decreased the swimming time to fatigue. After being subjected to the same weight-loaded swimming for 30 min, no obvious changes of blood lactate levels, gastrocnemius pAMPK/AMPK ratio, and glycogen contents were observed between intracerebroventricular CHBA-injected mice and vehicle-treated ones, which suggested a comparable degree of peripheral fatigue. Meanwhile, there were higher extracellular γ-aminobutyric acid (GABA) levels and lower extracellular glutamate levels and glutamate/GABA ratio in motor cortex of the intracerebroventricular CHBA-injected mice than that of vehicle-treated ones, indicating a greater extent of central fatigue in CHBA-injected mice than that in vehicle animals. Collectively, our results suggested that an increased level of brain l-lactate acts as a signaling molecule via activating GPR81, which in turn exacerbates central fatigue during exercise.


Assuntos
Ácido Láctico , Receptores Acoplados a Proteínas G , Animais , Camundongos , Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Fadiga/induzido quimicamente , Ácido gama-Aminobutírico/metabolismo , Glutamatos/metabolismo , Ácido Láctico/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
6.
Am J Physiol Cell Physiol ; 321(4): C671-C680, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469202

RESUMO

Hypoxia-induced pulmonary microvascular endothelial cell (PMVEC) monolayers hyperpermeability is vital for vascular leakage, which participates in vascular diseases, such as acute lung injury (ALI) and high-altitude pulmonary edema (HAPE). We previously observed that PMVEC permeability was markedly elevated in hypoxia when cocultured with primary type II alveolar epithelial cells (AECII) in which isthmin1 (ISM1) was highly upregulated. However, whether the upregulation of ISM1 plays a role in hypoxia-induced PMVEC hyperpermeability is unclear. In this study, we assessed the role of AECII-derived ISM1 in hypoxia-induced PMVEC hyperpermeability with an AECII/PMVEC coculture system and uncovered the underlying mechanism whereby hypoxia stimulates ISM1 gene expression. We found that ISM1 gene expression was upregulated in cultured AECII cells exposed to hypoxia (3% O2) and that AECII-derived ISM1 participated in hypoxia-induced hyperpermeability of PMVEC monolayers, as small interference RNA (siRNA)-mediated knockdown of ISM1 in AECII markedly attenuated the increase in PMVEC permeability in coculture system under hypoxia. In addition, we confirmed that ISM1 was regulated by hypoxia-inducible factor-1α (HIF1α) according to the evidence that silencing of HIF1α inhibited the hypoxia-mediated upregulation of ISM1. Mechanismly, overexpression of HIF1α transcriptionally activated ISM1 gene expression by directly binding to the conserved regulatory elements upstream of the ism1 locus. We identified a novel HIF-1-target gene ISM1, which involves in hyperpermeability of pulmonary microvascular endothelial cell monolayers under hypoxia. Our in vitro cell experiments implied that the upregulated ISM1 derived from alveolar epithelium might be a vital modulator in hypoxia-induced endothelial hyperpermeability and thereby implicates with hypoxic pulmonary-related diseases.


Assuntos
Células Epiteliais Alveolares/metabolismo , Permeabilidade Capilar , Células Endoteliais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Pulmão/irrigação sanguínea , Microvasos/metabolismo , Animais , Hipóxia Celular , Células Cultivadas , Técnicas de Cocultura , Impedância Elétrica , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Camundongos Endogâmicos C57BL , Comunicação Parácrina , Soroalbumina Bovina/metabolismo , Transdução de Sinais , Ativação Transcricional , Regulação para Cima
7.
Int J Mol Sci ; 22(8)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33918100

RESUMO

Streptococcus pneumoniae (S. pneumoniae) causes severe pulmonary diseases, leading to high morbidity and mortality. It has been reported that inflammasomes such as NLR family pyrin domain containing 3 (NLRP3) and absent in melanoma 2 (AIM2) play an important role in the host defense against S. pneumoniae infection. However, the role of NLRP6 in vivo and in vitro against S. pneumoniae remains unclear. Therefore, we investigated the role of NLRP6 in regulating the S. pneumoniae-induced inflammatory signaling pathway in vitro and the role of NLRP6 in the host defense against S. pneumoniae in vivo by using NLRP6-/- mice. The results showed that the NLRP6 inflammasome regulated the maturation and secretion of IL-1ß, but it did not affect the induction of IL-1ß transcription in S. pneumoniae-infected macrophages. Furthermore, the activation of caspase-1, caspase-11, and gasdermin D (GSDMD) as well as the oligomerization of apoptosis-associated speck-like protein (ASC) were also mediated by NLRP6 in S. pneumoniae-infected macrophages. However, the activation of NLRP6 reduced the expression of NF-κB and ERK signaling pathways in S. pneumoniae-infected macrophages. In vivo study showed that NLRP6-/- mice had a higher survival rate, lower number of bacteria, and milder inflammatory response in the lung compared with wild-type (WT) mice during S. pneumoniae infection, indicating that NLRP6 plays a negative role in the host defense against S. pneumoniae. Furthermore, increased bacterial clearance in NLRP6 deficient mice was modulated by the recruitment of macrophages and neutrophils. Our study provides a new insight on S. pneumoniae-induced activation of NLRP6 and suggests that blocking NLRP6 could be considered as a potential therapeutic strategy to treat S. pneumoniae infection.


Assuntos
Interações Hospedeiro-Patógeno , Inflamassomos/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Infecções Pneumocócicas/metabolismo , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/fisiologia , Animais , Caspase 1/metabolismo , Caspases Iniciadoras/metabolismo , Citocinas/biossíntese , Modelos Animais de Doenças , Suscetibilidade a Doenças , Peptídeos e Proteínas de Sinalização Intracelular/genética , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/patologia , Transdução de Sinais
8.
J Cell Physiol ; 235(1): 141-150, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31270801

RESUMO

Hypoxia-induced vascular smooth muscle cells (VSMCs) migration plays an important role in vascular remodeling and is implicated in vascular diseases, such as atherosclerosis and pulmonary hypertension. We previously observed the increased expression of krüppel-like factor 4 (KLF4) in VSMCs under hypoxia. However, whether the upregulation of KLF4 participates in hypoxia-induced VSMCs migration is still unknown. In this study, we demonstrated that KLF4 was an important player in the process of VSMCs migration under hypoxia since interference of KLF4 by small interfering RNA mostly dampened hypoxia-induced migration of VSMCs. In addition, using luciferase reporter and ChIP assays, we confirmed two hypoxia-inducible factor 1α (HIF1α) binding elements (located at -150 to -163 and -3922 to -3932) in the upstream regulatory region of klf4 locus and identified KLF4 as a novel direct target gene of HIF1α. Our findings unveil a novel regulatory mechanism that involves HIF1α-induced upregulation of KLF4, which plays a vital role in VSMCs migration under hypoxia.


Assuntos
Movimento Celular/fisiologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Músculo Liso Vascular/metabolismo , Oxigênio/farmacologia , Regulação para Cima/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Oxigênio/administração & dosagem , Regulação para Cima/fisiologia
9.
Plant Foods Hum Nutr ; 75(2): 154-160, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32030536

RESUMO

Increasing attention has been paid to the nutritional values and pharmacological effects of Ziziphus jujuba. Therefore, in this study, four phenolic and flavonoid fractions of 16 jujube cultivars from different geographic regions of China were separated and quantified. In addition, the antioxidant activity was evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH·) scavenging method and the ferric reducing antioxidant power (FRAP) assay. The total phenols and flavonoids contents ranged from 253.4 to 494.9 mg GAE/100 g and 125.3 to 425.4 mg rutin/100 g, respectively. Subsquently, a total of 10 phenolic acids and two flavonoids were identified, and most quantified phenolic acids with antioxidant activity were mainly present in the glycosided and insoluble-bound phenolic fractions. The results of this study indicate that some jujube cultivars, especially Zanghuang Z. jujuba, Leling Z. jujuba, and Jiaxian Z. jujuba could be selected to promote a healthy diet due to their more plentiful nutritional and phytochemical beneficial effects.


Assuntos
Ziziphus , Antioxidantes , China , Flavonoides , Extratos Vegetais
10.
J Exp Biol ; 222(Pt 14)2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31253714

RESUMO

It is well known that exercise-induced fatigue is exacerbated following hypoxia exposure and may arise from central and/or peripheral mechanisms. To assess the relative contribution of peripheral and central factors to exercise-induced fatigue under hypoxia, a rat model of fatigue by a bout of exhaustive swimming was established and fatigue-related biochemical changes in normoxic and severe hypoxic conditions were compared. Rats were randomly divided into four groups: normoxia resting (NR), exhaustive swimming (NE), hypoxia resting (HR) and exhaustive swimming (HE). The swimming time to exhaustion with a weight equal to 2.5% of their body weight reduced under hypoxia. There were lower blood lactate levels, lower gastrocnemius pAMPK/AMPK ratios and higher gastrocnemius glycogen contents in the HE than in the NE groups, which all suggested a lower degree of peripheral fatigue in the HE group than in the NE group. Meanwhile, there was a significant increase in striatal 3,4-dihydroxyphenylacetic acid (DOPAC) caused by exhaustive swimming under normoxia, whereas this increase was almost blunted under severe hypoxia, indicating that hypoxia might exacerbate exercise-induced central fatigue. These biochemical changes suggest that from normoxia to severe hypoxia, the relative contribution of peripheral and central factors to exercise-induced fatigue alters, and central fatigue may play a predominant role in the decline in exercise performance under hypoxia.


Assuntos
Corpo Estriado/fisiologia , Hipóxia/fisiopatologia , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Natação , Anaerobiose , Animais , Masculino , Oxigênio/análise , Ratos , Ratos Sprague-Dawley
11.
Mol Cell Probes ; 44: 51-56, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30771482

RESUMO

Enzootic nasal tumor virus 2 (ENTV-2), the aetiological agent of enzootic nasal adenocarcinoma in goats, is prevalent in China; resulting in substantial economic losses to the goat-breeding industry. Therefore, it is necessary to establish an efficient detection method for the diagnosis and prevention of ENTV-2 infection. More recently, EvaGreen is emerging as a novel alternative fluorescent dye for quantitative real-time PCR because of its low cost, specific amplification and high resolution. In this study, we developed a specific, sensitive, and cost-effective detection method-an EvaGreen-based real-time PCR assay for the detection of ENTV-2. This assay exhibited high specificity and sensitivity and was able to detect ENTV-2 at concentrations as low as 3.0 × 101 copies, which was more sensitive than the conventional PCR method (detection limit, 3.0 × 102 copies). In addition, the reproducibility test indicated that EvaGreen dye in our assay had a good reproducibility. In conclusion, we report that a highly sensitive, specific, and cost-effective EvaGreen-based real-time PCR assay is successful for the rapid detection of ENTV-2.


Assuntos
Betaretrovirus/genética , Betaretrovirus/isolamento & purificação , Neoplasias Nasais/virologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Zoonoses/virologia , Animais , Primers do DNA/metabolismo , Cabras/virologia , Limite de Detecção , RNA Viral/genética , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Arch Virol ; 164(6): 1647-1650, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877451

RESUMO

Enzootic nasal adenocarcinoma (ENA) of goats, characterized by transformation of epithelial cells of the ethmoid turbinates, is caused by enzootic nasal tumor virus 2 (ENTV-2). ENTV-2 belongs to the genus Betaretrovirus and has extended its distribution globally with a high prevalence; however, the genetic diversity and genotypic distribution for ENTV-2 have not been analyzed systematically due to the limited availability of sequence data. In this study, an infection by ENTV-2 was detected by RT-PCR in Chongqing in July 2018, and the complete sequence of one strain (CQ1) was determined. Phylogenetic analysis indicated a high degree of genetic heterogeneity among ENTV-2 sequences, with the existence of two main lineages. Lineage 1 and 2 were composed of ENTV-2 from China and the UK, respectively. Although CQ1 was closely related to recent ENTV-2 strains collected in the neighboring provinces of Chongqing (Shaanxi and Sichuan), it formed a separate sublineage of lineage 1 (sublineage 1.3). This report will enhance our understanding of the epidemiology of ENTV-2 in China.


Assuntos
Betaretrovirus/classificação , Técnicas de Genotipagem/métodos , Doenças das Cabras/virologia , Neoplasias Nasais/veterinária , Análise de Sequência de RNA/métodos , Animais , Betaretrovirus/genética , Betaretrovirus/isolamento & purificação , China , Variação Genética , Cabras , Neoplasias Nasais/virologia , Filogenia , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Reino Unido
13.
Biochem Biophys Res Commun ; 507(1-4): 217-222, 2018 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-30446225

RESUMO

Streptococcus pneumoniae is a pathogen of significant clinical importance worldwide that can cause severe invasive diseases, such as pneumonia, otitis media and meningitis. Inflammsomes has been reported to participate in host defense against S. pneumoniae infection. S. pneumoniae could induce the assembly of the nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3)/absent in melanoma 2 (AIM2) inflammasome, which mediates the activation of caspase-1 and the subsequent maturation of Interleukin-1ß (IL-1ß). However, the precise signals that activate inflammasomes during pneumococcal infection remain to be fully elucidated. In the present study, primary mouse macrophages were selected as a cell model, and the effects of kinases on inflammasome activity induced by S. pneumoniae infection were examined by ELISA and western blotting after pretreatment with a kinase inhibitor. Here, we show that Syk and JNK signaling are required for S. pneumoniae-induced activation of the inflammasome. Inhibitors of Syk and JNK almost abolished the oligomerization of apoptosis-associated speck-like protein containing a caspase-activating and recruitment domain (ASC) and subsequent caspase-1 activation and IL-1ß secretion. Moreover, pneumolysin (PLY) participated in this process and was critical for Syk/JNK activation. These results suggested that the Syk/JNK signaling pathway may play a vital role in the inflammasome activation and modulate host immune responses against S. pneumoniae.


Assuntos
Inflamassomos/metabolismo , Sistema de Sinalização das MAP Quinases , Macrófagos/enzimologia , Macrófagos/microbiologia , Infecções Pneumocócicas/metabolismo , Streptococcus pneumoniae/fisiologia , Estreptolisinas/metabolismo , Quinase Syk/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Caspase 1/metabolismo , Feminino , Interleucina-1beta/metabolismo , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/patologia
14.
Neurosignals ; 24(1): 25-39, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27300021

RESUMO

BACKGROUND: Regeneration of injured axons in adult mammalian central nervous system (CNS) is not spontaneous. Nogo is a major inhibitory molecule contributing to axon regeneration failure. The molecular mechanisms of Nogo inhibition of axon regeneration are not completely understood. To further investigate the underlying mechanisms, we studied the effects of Nogo-p4, a 25-amino acid core inhibitory fragment of Nogo, on nerve growth factor (NGF)-induced TrkA signaling. METHODS: NGF-differentiated PC12 cells were used as cell models. The effects of Nogo-p4 on two key components of TrkA signaling, phosphorylated Erk1/2 and Akt, were analyzed by western blot. Co-immunoprecipitation experiments were performed to detect the formation of NgR1/p75 complexes. Neurite growth was quantified by measuring the neurite length. RESULTS: Nogo-p4 did not significantly affect TrkA signaling induced by 100 ng/ml NGF, but signaling was suppressed when an NGF concentration of 5 ng/ml was used. Further investigation demonstrated that Nogo-p4 affected TrkA signaling in an NGF concentration-dependent manner. Nogo-p4 suppression of TrkA signaling was strong at low (1 and 5 ng/ml), moderate at intermediate (25 ng/ml), but absent at high (50 and 100 ng/ml) NGF concentrations. NEP1-40 attenuated, and NgR1 overexpression enhanced, Nogo-p4 suppression of TrkA signaling induced by low concentrations of NGF. High but not low concentrations of NGF reduced the formation of NgR1/p75 complexes triggered by Nogo-p4. Nogo-p4 strongly inhibited neurite growth induced by low rather than high concentrations of NGF. CONCLUSION: Nogo-p4 binding with NgR1 suppresses TrkA signaling induced by low concentrations of NGF in differentiated PC12 cells. Suppression of NGF-induced TrkA signaling may be another mechanism by which Nogo inhibits neurite growth.

15.
Stroke ; 46(5): 1328-36, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25782468

RESUMO

BACKGROUND AND PURPOSE: To determine whether the receptor for advanced glycation end-products (RAGE) plays a role in early brain injury from intracerebral hemorrhage (ICH), RAGE expression and activation after injury were examined in a rat model of ICH with or without administration of a RAGE-specific antagonist (FPS-ZM1). METHODS: Autologous arterial blood was injected into the basal ganglia of rats to induce ICH. The motor function of the rats was examined, and water content was detected after euthanization. Blood-brain barrier permeability was determined by Evans blue staining and colloidal gold nanoparticle tracers. Nerve fiber injury in white matter was determined by diffusion tensor imaging analysis, and the expression of target genes was analyzed by Western blotting and quantitative reverse transcription polymerase chain reaction. FPS-ZM1 was administered by intraperitoneal injection. RESULTS: Expression of RAGE and its ligand high-mobility group protein B1 were increased at 12 hours after ICH, along with blood-brain barrier permeability and perihematomal nerve fiber injury. RAGE and nuclear factor-κB p65 upregulation were also observed when FeCl2 was infused into the basal ganglia at 24 hours. FPS-ZM1 administration resulted in significant improvements of blood-brain barrier damage, brain edema, motor dysfunction, and nerve fiber injury, and the expression of RAGE, nuclear factor-κB p65, proinflammatory mediators interleukin 1ß, interleukin-6, interleukin-8R, cyclooxygenase-2, inducible nitric oxide synthase, and matrix metallopeptidase-9 was attenuated. Moreover, decreases in claudin-5 and occludin expression were partially recovered. FPS-ZM1 also reversed FeCl2-induced RAGE and nuclear factor-κB p65 upregulation. CONCLUSIONS: RAGE signaling is involved in blood-brain barrier and white matter fiber damage after ICH, the initiation of which is associated with iron. RAGE antagonists represent a novel therapeutic intervention to prevent early brain injury after ICH.


Assuntos
Benzamidas/uso terapêutico , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Hemorragias Intracranianas/tratamento farmacológico , Hemorragias Intracranianas/patologia , Receptores Imunológicos/antagonistas & inibidores , Animais , Água Corporal/metabolismo , Química Encefálica/efeitos dos fármacos , Citocinas/metabolismo , Imagem de Tensor de Difusão , Regulação da Expressão Gênica/efeitos dos fármacos , Hemorragias Intracranianas/psicologia , Masculino , Fibras Nervosas/patologia , Equilíbrio Postural/efeitos dos fármacos , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptor para Produtos Finais de Glicação Avançada
16.
Tumour Biol ; 36(9): 6797-803, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25835977

RESUMO

The survival rate of esophageal squamous cell cancer (ESCC) patients is still dismal. Therefore, novel prognostic biomarkers are critically needed for patients with ESCC. SLC9A9 has been reported to be downregulated in hormone-sensitive prostate cancer; however, the correlations between SLC9A9 and ESCC prognosis are unclear. The aim of this study is to evaluate the expression and prognostic significance of SLC9A9 in resectable ESCC. Fresh frozen or paraffin-embedded samples were collected from 167 or 59 patients with resectable ESCC, respectively. The expression of SLC9A9 was assessed by reverse transcription and quantitative real-time polymerase chain reaction analysis (167 patients) and immunohistochemistry (61 patients). The expression of SLC9A9 was not associated with patient clinicopathological characteristics at both transcription and protein levels. The 5-year overall survival in the high SLC9A9 messenger RNA (mRNA) group (n = 106) was poorer than that in the low expression group (n = 61) (34.6 vs. 65.9 %, P < 0.001). Notably, higher SLC9A9 protein expression was also correlated with lower 5-year overall survival (33.1 vs. 66.5 %, P = 0.023). Moreover, multivariate analysis revealed that SLC9A9 mRNA (HR, 2.41; 95 % CI, 1.47-3.97; P = 0.001) and protein (HR, 2.31; 95 %CI, 1.06-5.02; P = 0.034) were independent prognostic factors. In conclusion, the expression of SLC9A9 can be a prognostic predictor for ESCC.


Assuntos
Biomarcadores Tumorais/biossíntese , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Prognóstico , Trocadores de Sódio-Hidrogênio/biossíntese , Idoso , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Trocadores de Sódio-Hidrogênio/genética
17.
J Surg Oncol ; 111(4): 365-70, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25418352

RESUMO

BACKGROUD AND OBJECTIVES: Health-related quality of life (HRQL) is of great importance in cancer management. The aim was to identify factors that influence postoperative HRQL in esophageal carcinoma patients. METHODS: A prospective cohort study was conducted to enroll 196 patients with esophageal carcinoma from November 2012 to June 2013. Sociademographic and clinicopathological parameters were recorded in detail. EORTC-QLQ C30 and ES18 were used to assess HRQL before surgery, at discharge, 1 and 6 months after discharge. Logistic regression models were used to identify factors independently influencing quality of life at 6 months after discharge. RESULTS: HRQL dramatically decreased after esophagectomy, but restored within 6 months in the most scales. Multivariate logistic regression analysis showed that gender (P = 0.002) and anastomotic stricture (P = 0.001) were the independent predictors of poor global quality-of-life 6 months after discharge. Anastomotic stricture occurred in 22 patients (11.2%), and their performance in social function (P = 0.04), problems with eating (P = 0.006), choking when swallowing (P < 0.001) were significantly poorer at 6 months after discharge. There were not significant differences in global quality-of-life between patients with and without anastomotic leakage at three postoperative assessments. CONCLUSIONS: Postoperative HRQL is restored within 6 months after discharge. Occurrence of anastomotic stricture significantly decreases HRQL after esophagectomy.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Neoplasias Esofágicas/cirurgia , Esofagectomia , Qualidade de Vida , Carcinoma/cirurgia , Estenose Esofágica/etiologia , Estenose Esofágica/psicologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Prospectivos , Fatores Sexuais
18.
J Cell Physiol ; 229(10): 1511-20, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24615545

RESUMO

Pulmonary artery smooth muscle cells (PASMCs) are associated with the development of hypoxic pulmonary hypertension (HPH). Recent studies have implicated a critical role for microRNAs (miRNAs) in HPH; however, their expression and regulation in hypoxia-mediated phenotypic modulation of PASMCs remains largely unclear. Here, we report that miR-9 was induced in hypoxia and involved in a hypoxia-induced phenotypic switch in rat primary PASMCs. Knockdown of miR-9 followed by hypoxia exposure attenuated PASMCs proliferation and enhanced the expression of contractile genes in vascular smooth muscle cells (VSMCs), while overexpression of miR-9 in normoxia promoted a proliferative phenotype in PASMCs. The primary transcripts of miR-9-1 and miR-9-3, but not miR-9-2, increased dramatically after hypoxia, whereas silencing of the hypoxia-associated transcription factor HIF-1α following hypoxia exposure abolished the enhancement of both primary transcripts in PASMCs. Using in silico analysis, we found three putative HIF-1α binding motifs on miR-9-1 and one motif on miR-9-3 located within the 5-kb region upstream of the transcriptional start sites. Chromatin immunoprecipitation assay revealed that hypoxia enhanced the direct interaction between HIF-1α and the regulatory elements of miR-9-1 and miR-9-3. Reporter assays showed that the regulatory regions of miR-9-1 and miR-9-3 behaved as enhancers in a HIF-1α-dependent manner during hypoxia. Taken together, our data uncover a regulatory mechanism involving HIF-1α-mediated up-regulation of miR-9, which plays a role in the hypoxia-induced phenotypic switch of PASMCs.


Assuntos
Proliferação de Células , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , MicroRNAs/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Sítios de Ligação , Hipóxia Celular , Células Cultivadas , Imunoprecipitação da Cromatina , Biologia Computacional , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Fenótipo , Artéria Pulmonar/metabolismo , Interferência de RNA , Ratos , Fatores de Tempo , Sítio de Iniciação de Transcrição , Transfecção , Regulação para Cima
19.
Cancer Sci ; 105(12): 1638-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25287715

RESUMO

Alcohol is a well-established cause of esophageal carcinoma, but its effect on survival is little known and contradictory. To clarify whether drinking is an independent predictor of survival in esophageal carcinoma, 2151 Chinese patients, receiving surgical resection from January 1997 to December 2008, were followed until March 2014. Cox proportional hazards analysis was applied to evaluate the prognostic effect of alcohol consumption. The median follow-up was 64 months. The median overall survival (OS; 42 months) and disease-free survival (DFS; 33 months) for never-drinkers were significantly higher than ever-drinkers (27 and 22 months, respectively). In the multivariate Cox model that was adjusted for age, weight loss, stage according to criteria set by the American Joint Committee on Cancer, radicality of surgery, adjuvant treatment, smoking status, and gender, the hazard ratios of ever-drinking were 1.22 (1.06-1.41, P = 0.005) on OS, and 1.16 (1.01-1.34, P = 0.037) on DFS. The hazardous effect on OS and DFS of drinking grew statistically significantly in a dose-dependent manner with increasing amount of alcohol consumption per day (both P-value for trend < 0.05). The predictive effect of drinking on OS (P = 0.596) or DFS (P = 0.207) was not significant in the subgroup with esophageal adenocarcinoma (n = 195). The current study revealed that the survival is shortened, of those patients who consume alcohol before diagnosis of esophageal squamous cell carcinoma, which are not attributable to differences in stage, smoking status, and gender. Alcohol control should be emphasized to reduce mortality of esophageal carcinoma, and further outcome studies should include alcohol as a potential prognosticator.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Neoplasias Esofágicas/mortalidade , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , China , Intervalo Livre de Doença , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Análise de Sobrevida
20.
Chin Med Sci J ; 29(3): 148-55, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25264882

RESUMO

OBJECTIVES: To reveal etiologies of persistent isolated hematuria (PIH) through ultrastructural pathological examination, to disclose clinicopathological correlation in cases with PIH, and to summarize appropriate management of patients with PIH. METHODS: we retrospectively studied 155 PIH patients receiving renal biopsy between January, 2003 and December, 2008 in Peking Union Medical College Hospital. All the clinical data and follow-up result were analyzed. RESULTS: All subjects included 38 children and 117 adults, with mean age of 11.38±3.25 years for children and 35.17±8.44 years for adults. Thin basement membrane nephropathy (TBMN) was the most common pathology (55.3% of children and 49.6% of adults), followed by IgA nephropathy (18.4% of children and 32.5% of adults, mainly grade 2-3) and mesangial proliferative glomerulonephritis (MsPGN) without IgA deposition (13.2% of children and 12.8% of adults). Besides, Alport syndrome (2.6% of children) and membrane nephropathy (2.6% of children and 0.9% of adults) were demonstrated as other causes of PIH. Elevated mean arteral pressure or protein excretion rate, as well as episodic macrohematuria, indicated higher risk for MsPGN rather than TBMN. On the other hand, severity of microhematuria was irrelevant to pathological types of PIH. Totally, 86 patients were followed up and 37 cases therein stayed on track for long term (mean duration 41.11?28.92 months, range 8-113 months). Most cases had benign clinical course except 3 cases with TBMN, 5 cases with IgA nephropathy, 1 case with MsPGN (without IgA deposition), and 1 case with Alport syndrome, who developed hypertension or proteinuria. All of them were administered timely intervention. CONCLUSIONS: Close follow-up should be required as the primary management for PIH. Equally important is careful monitoring for early identification of undesirable predictors; while renal biopsy and other timely intervention are warranted if there is hypertension, significant proteinuria or renal impairment.


Assuntos
Hematúria/patologia , Rim/patologia , Adolescente , Adulto , Biópsia , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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