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1.
Nat Commun ; 15(1): 3213, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615060

RESUMEN

Oxidative stress-induced lipid accumulation is mediated by lipid droplets (LDs) homeostasis, which sequester vulnerable unsaturated triglycerides into LDs to prevent further peroxidation. Here we identify the upregulation of lipopolysaccharide-binding protein (LBP) and its trafficking through LDs as a mechanism for modulating LD homeostasis in response to oxidative stress. Our results suggest that LBP induces lipid accumulation by controlling lipid-redox homeostasis through its lipid-capture activity, sorting unsaturated triglycerides into LDs. N-acetyl-L-cysteine treatment reduces LBP-mediated triglycerides accumulation by phospholipid/triglycerides competition and Peroxiredoxin 4, a redox state sensor of LBP that regulates the shuttle of LBP from LDs. Furthermore, chronic stress upregulates LBP expression, leading to insulin resistance and obesity. Our findings contribute to the understanding of the role of LBP in regulating LD homeostasis and against cellular peroxidative injury. These insights could inform the development of redox-based therapies for alleviating oxidative stress-induced metabolic dysfunction.


Asunto(s)
Proteínas de Fase Aguda , Gotas Lipídicas , Glicoproteínas de Membrana , Proteínas de Fase Aguda/metabolismo , Proteínas Portadoras/metabolismo , Homeostasis , Gotas Lipídicas/metabolismo , Lipopolisacáridos/metabolismo , Glicoproteínas de Membrana/metabolismo , Estrés Oxidativo/genética , Estrés Oxidativo/fisiología , Triglicéridos
3.
Mol Ther Nucleic Acids ; 27: 535-546, 2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35036064

RESUMEN

Tumor cells actively release large quantities of exosomes, which pivotally participate in the regulation of cancer biology, including head and neck cancer (HNC). Exosome biogenesis and release are complex and elaborate processes that are considered to be similar to the process of exocyst-mediated vesicle delivery. By analyzing the expression of exocyst subunits and their role in patients with HNC, we aimed to identify exocyst and its functions in exosome biogenesis and investigate the molecular mechanisms underlying the regulation of exosome transport in HNC cells. We observed that exocysts were highly expressed in HNC cells and could promote exosome secretion in these cells. In addition, downregulation of exocyst expression inhibited HN4 cell proliferation by reducing exosome secretion. Interestingly, immunofluorescence and electron microscopy revealed the accumulation of multivesicular bodies (MVBs) after the knockdown of exocyst. Autophagy, the major pathway of exosome degradation, is not activated by this intracellular accumulation of MVBs, but these MVBs are consumed when autophagy is activated under the condition of cell starvation. Rab11a, a small GTPase that is involved in MVB fusion, also interacted with the exocyst. These findings suggest that the exocyst can regulate exosome biogenesis and participate in the malignant behavior of tumor cells.

4.
Aging Cell ; 21(1): e13532, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34905649

RESUMEN

The "rejuvenating" effect of growth differentiation factor 11 (GDF11) is called into question recently, and its role, as well as plausible signaling mechanisms in liver senescence, is unclear. To overexpress or knockdown GDF11, aged male mice are injected with a single dose of adeno-associated viruses-GDF11 or adenovirus-small hairpin RNA-GDF11, respectively. GDF11 overexpression significantly accelerates liver senescence in aged mice, whereas GDF11 knockdown has opposite effects. Concomitantly, autophagic flux is impaired in livers from GDF11 overexpression mice. Conversely, GDF11 knockdown increases autophagic flux. Moreover, rapamycin successfully restores the impaired autophagic flux and alleviates liver senescence in GDF11 overexpression mice, while the GDF11 knockdown-mediated benefits are abolished by the autophagy inhibitor bafilomycin A1. GDF11 leads to a drop in lysosomal biogenesis resulting in defective autophagic flux at autophagosome clearance step. Mechanistically, GDF11 significantly activates mammalian target of rapamycin complex 1 (mTORC1) and subsequently represses transcription factor EB (TFEB), a master regulator of lysosomal biogenesis and autophagy. Inhibition of mTORC1 or TFEB overexpression rescues the GDF11-impaired autophagic flux and cellular senescence. Hepatocyte-specific deletion of GDF11 does not alter serum GDF11 levels and liver senescence. Collectively, suppression of autophagic activity via mTORC1/TFEB signaling may be a critical molecular mechanism by which GDF11 exacerbates liver senescence. Rather than a "rejuvenating" agent, GDF11 may have a detrimental effect on liver senescence.


Asunto(s)
Autofagia/genética , Proteínas Morfogenéticas Óseas/metabolismo , Factores de Diferenciación de Crecimiento/metabolismo , Hígado/patología , Lisosomas/efectos de los fármacos , Animales , Senescencia Celular , Humanos , Masculino , Ratones
5.
Front Immunol ; 12: 681810, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34295331

RESUMEN

Inflammation, which is induced by the immune response, is recognized as the driving factor in many diseases, including infections and inflammatory diseases, metabolic disorders and cancers. Genetic variations in pivotal genes associated with the immune response, particularly single nucleotide polymorphisms (SNPs), may account for predisposition and clinical outcome of diseases. Lipopolysaccharide (LPS)-binding protein (LBP) functions as an enhancer of the host response to LPS, the main component of the outer membrane of gram-native bacteria. Given the crucial role of LBP in inflammation, we will review the impact of SNPs in the LBP gene on infections and inflammatory diseases, metabolic disorders and cancers.


Asunto(s)
Proteínas de Fase Aguda/genética , Proteínas Portadoras/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Glicoproteínas de Membrana/genética , Polimorfismo de Nucleótido Simple , Proteínas de Fase Aguda/metabolismo , Alelos , Animales , Proteínas Portadoras/metabolismo , Enfermedades Transmisibles/etiología , Enfermedades Transmisibles/metabolismo , Genotipo , Humanos , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Glicoproteínas de Membrana/metabolismo , Enfermedades Metabólicas/diagnóstico , Enfermedades Metabólicas/genética , Enfermedades Metabólicas/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología
7.
Front Immunol ; 10: 1612, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31402909

RESUMEN

Sepsis-induced acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) remains the leading complication for mortality caused by bacterial infection. The regulatory T (Treg) cells appear to be an important modulator in resolving lung injury. Despite the extensive studies, little is known about the role of macrophage HMGB1/PTEN/ß-catenin signaling in Treg development during ALI. Objectives: This study was designed to determine the roles and molecular mechanisms of HMGB1/PTEN/ß-catenin signaling in mediating CD4+CD25+Foxp3+ Treg development in sepsis-induced lung injury in mice. Setting: University laboratory research of First Affiliated Hospital of Anhui Medical University. Subjects: PTEN/ß-catenin Loxp and myeloid-specific knockout mice. Interventions: Groups of PTENloxp/ß-cateninloxp and myeloid-specific PTEN/ß-catenin knockout (PTENM-KO/ß-cateninM-KO) mice were treated with LPS or recombinant HMGB1 (rHMGB1) to induce ALI. The effects of HMGB1-PTEN axis were further analyzed by in vitro co-cultures. Measures and Main Results: In a mouse model of ALI, blocking HMGB1 or myeloid-specific PTEN knockout (PTENM-KO) increased animal survival/body weight, reduced lung damage, increased TGF-ß production, inhibited the expression of RORγt and IL-17, while promoting ß-catenin signaling and increasing CD4+CD25+Foxp3+ Tregs in LPS- or rHMGB-induced lung injury. Notably, myeloid-specific ß-catenin ablation (ß-cateninM-KO) resulted in reduced animal survival and increased lung injury, accompanied by reduced CD4+CD25+Foxp3+ Tregs in rHMGB-induced ALI. Furthermore, disruption of macrophage HMGB1/PTEN or activation of ß-catenin significantly increased CD4+CD25+Foxp3+ Tregs in vitro. Conclusions: HMGB1/PTEN/ß-catenin signaling is a novel pathway that regulates Treg development and provides a potential therapeutic target in sepsis-induced lung injury.


Asunto(s)
Lesión Pulmonar Aguda/etiología , Lesión Pulmonar Aguda/metabolismo , Proteína HMGB1/metabolismo , Inmunomodulación , Fosfohidrolasa PTEN/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , beta Catenina/metabolismo , Lesión Pulmonar Aguda/patología , Animales , Biomarcadores , Citocinas/metabolismo , Modelos Animales de Enfermedad , Inmunofenotipificación , Mediadores de Inflamación/metabolismo , Lipopolisacáridos/efectos adversos , Activación de Linfocitos , Ratones , Ratones Transgénicos , Transducción de Señal
8.
Front Oncol ; 9: 535, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31293973

RESUMEN

Background: Inactivation of microRNA-100 (miR-100) is involved in hepatocellular carcinoma (HCC) and miR-100 behaves as a tumor suppressor. To understand miR-100 function in HCC genesis and development in vivo, we developed hepatocyte-specific miR-100 deficient mice. Methods: Mice homozygous for floxed miR-100 allele that carried the Alb-Cre transgene (miR-100flox/floxAlb -Cre+) were developed by mating miR-100flox/flox mice with Alb-Cre+/+mice. The mice tails DNA were genotyped using the primers for LoxP sites and Cre recombinase, respectively. The specific deletion of miR-100 in the livers was verified by quantitative Real-time PCR (qRT-PCR). HE-staining was performed for histology analysis. Liver function was assessed by transaminase activity. The metabolic profiles of the hepatocytes were detected using a Seahorse XFe24 extracellular flux analyzer. The direct targets of miR-100 (such as IGF1R-ß, mTOR and CDC25A) and HCC related protein (SHP-2) were detected by qRT-PCR and Western blot in liver tissues. Results: The resultant homozygous knockout mice with genotype of miR-100flox/flox-Alb-Cre+ showed an 80% decrease in hepatic miR-100 expression. In adult mice, miR-100 knockout has no effect on the liver function and morphology. In aged mice, HE staining showed that miR-100 knockout caused infiltration of inflammatory cells and expansion of hepatocellular nuclei. Consistently, liver function was impaired in miR-100 knockout aged mice as indicated by increased serum AST and ALT levels. The metabolic analysis demonstrated that the miR-100 knockout hepatocytes tend to adopt glycolysis. The expressions of the miR-100 target genes, such as IGF1R-ß, CDC25A and mTOR, were increased. In addition, the known HCC related protein, SHP-2 also was up-regulated in the knockout livers. Conclusions: We successfully generated a miR-100 hepatocyte-specific knock-out mouse model. The malignant transformation related to HCC were observed in aged mice. Therefore, this model is suitable for investigating the mechanism of miR-100 inactivation contributing to HCC genesis in vivo.

9.
J Immunol Res ; 2018: 6085095, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30525057

RESUMEN

INTRODUCTION: Sepsis is the primary cause of death from infection. We wanted to improve the outcome of sepsis by stimulating innate immunity in combination with modulating the severity of inflammatory responses in rats. METHOD: Sepsis was induced by the injection of feces suspension (control). A 5-day course of G-CSF treatment was given before the septic insult (G-CSF). The inflammatory response was decreased using various doses of the LPS-blocking peptide LBPK95A (5 mg/kg = 100% Combi group, 0.5 mg/kg = 10% Combi group, and 0.05 mg/kg = 1% Combi group). Survival rates were observed. Bacterial clearance, neutrophil infiltration, tissue damage, and the induction of hepatic and systemic inflammatory responses were determined 2 h and 12 h after the septic insult. RESULTS: High-dose LBPK95A (100% Combi) reduced the survival rate to 10%, whereas low-dose LBPK95A (10% and 1% Combi) increased the survival rates to 50% and 80%, respectively. The survival rates inversely correlated with multiorgan damage as indicated by the serum levels of ALT and urea. G-CSF treatment increased the white blood cell counts, hepatic neutrophil infiltration, and bacterial clearance in the liver, lung, and blood. The blockade of the LPS-LBP interaction decreased neutrophil infiltration, led to increased white blood cell count, and decreased hepatic neutrophil infiltration, irrespective of dose. However, bacterial clearance improved in the 1% and 10% Combi groups but worsened in the 100% Combi group. G-CSF increased TNF-α and IL-6 levels. Irrespective of dose, the blockade of the LPS-LBP interaction was associated with low systemic cytokine levels and delayed increases in hepatic TNF-α and IL-6 mRNA expression. The delayed increase in cytokines was associated with the phosphorylation of STAT3 and AKT. CONCLUSION: Our results revealed that increasing innate immunity by G-CSF pretreatment and decreasing inflammatory responses using LBPK95A improved the survival rates in a rat sepsis model and could be a novel strategy to treat sepsis.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos/inmunología , Inflamación/inmunología , Péptidos/inmunología , Sepsis/inmunología , Animales , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Humanos , Inmunidad Innata , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolisacáridos/antagonistas & inhibidores , Masculino , Infiltración Neutrófila , Péptidos/farmacología , Ratas , Ratas Endogámicas Lew , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
10.
Aging Cell ; 17(1)2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29210183

RESUMEN

Recent studies showing the therapeutic effect of young blood on aging-associated deterioration of organs point to young blood as the solution for clinical problems related to old age. Given that defective autophagy has been implicated in aging and aging-associated organ injuries, this study was designed to determine the effect of young blood on aging-induced alterations in hepatic function and underlying mechanisms, with a focus on autophagy. Aged rats (22 months) were treated with pooled plasma (1 ml, intravenously) collected from young (3 months) or aged rats three times per week for 4 weeks, and 3-methyladenine or wortmannin was used to inhibit young blood-induced autophagy. Aging was associated with elevated levels of alanine transaminase and aspartate aminotransferase, lipofuscin accumulation, steatosis, fibrosis, and defective liver regeneration after partial hepatectomy, which were significantly attenuated by young plasma injections. Young plasma could also restore aging-impaired autophagy activity. Inhibition of the young plasma-restored autophagic activity abrogated the beneficial effect of young plasma against hepatic injury with aging. In vitro, young serum could protect old hepatocytes from senescence, and the antisenescence effect of young serum was abrogated by 3-methyladenine, wortmannin, or small interfering RNA to autophagy-related protein 7. Collectively, our data indicate that young plasma could ameliorate age-dependent alterations in hepatic function partially via the restoration of autophagy.


Asunto(s)
Envejecimiento/fisiología , Autofagia/fisiología , Hepatocitos/fisiología , Regeneración Hepática/fisiología , Animales , Hígado Graso/metabolismo , Hepatectomía/métodos , Hígado/metabolismo , Masculino , Ratas Sprague-Dawley
11.
Cancer Biol Ther ; 18(12): 965-973, 2017 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-28956730

RESUMEN

Chronic arsenic treatment induces epithelial-mesenchymal transition (EMT) and promotes tumorigenicity, but the mechanism is unclear. MiR-100 has been shown to be involved in this biologic process. In this study, we hypothesize that inactivation of miR-100 combined with low concentration of arsenic exposure could promote the malignant transformation of human bronchial epithelial cells (BEAS-2B cell) by promoting EMT. To test this hypothesis, BEAS-2B cells were treated with low-dose of As2O3 chronically, and lentiviral vectors were used to mediate the inhibition of miR-100 expression. Flow cytometry, cloning formation, and transwell assays were used to examine cell cycle progression, cell proliferation, and cell migration, respectively. The mouse xenograft model was used to investigate the cell malignant growth in vivo, and western blot was used to detect EMT related marker expressions. Our results showed that, the inactivation of miR-100 combined with arsenic treatment significantly promoted the proliferation, viability, and migration of BEAS-2B cells in vitro, and tumorigenesis in vivo. Consistently, the EMT related marker expressions were also significantly increased in corresponding groups. Our data indicate that inactivation of miR-100 combined with chronic arsenic treatment promotes tumorigenicity of BEAS-2B cells via activation of EMT. This novel insight may help us to better understand the pathogenesis of arsenic carcinogenesis.


Asunto(s)
Arsénico/toxicidad , Carcinogénesis/genética , Transición Epitelial-Mesenquimal/genética , MicroARNs/genética , Animales , Bronquios/efectos de los fármacos , Bronquios/metabolismo , Bronquios/patología , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Transformación Celular Neoplásica/genética , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Xenoinjertos , Humanos , Ratones , MicroARNs/metabolismo , Transducción de Señal/genética
12.
Int J Mol Sci ; 18(1)2017 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-28275217

RESUMEN

Ischemia/reperfusion injury (IRI) occurs inevitably in liver transplantations and frequently during major resections, and can lead to liver dysfunction as well as systemic disorders. High-mobility group box 1 (HMGB1) plays a pathogenic role in hepatic IRI. In the normal liver, HMGB1 is located in the nucleus of hepatocytes; after ischemia reperfusion, it translocates to the cytoplasm and it is further released to the extracellular space. Unlike the well-explored functions of nuclear and extracellular HMGB1, the role of cytoplasmic HMGB1 in hepatic IRI remains elusive. We hypothesized that cytoplasmic HMGB1 interacts with binding proteins involved in the hepatocellular response to IRI. In this study, binding proteins of cytoplasmic HMGB1 during hepatic IRI were identified. Liver tissues from rats with warm ischemia reperfusion (WI/R) injury and from normal rats were subjected to cytoplasmic protein extraction. Co-immunoprecipitation using these protein extracts was performed to enrich HMGB1-protein complexes. To separate and identify the immunoprecipitated proteins in eluates, 2-dimensional electrophoresis and subsequent mass spectrometry detection were performed. Two of the identified proteins were verified using Western blotting: betaine-homocysteine S-methyltransferase 1 (BHMT) and cystathionine γ-lyase (CTH). Therefore, our results revealed the binding of HMGB1 to BHMT and CTH in cytoplasm during hepatic WI/R. This finding may help to better understand the cellular response to IRI in the liver and to identify novel molecular targets for reducing ischemic injury.


Asunto(s)
Citoplasma/metabolismo , Proteína HMGB1/metabolismo , Hepatocitos/metabolismo , Daño por Reperfusión/metabolismo , Animales , Western Blotting , Electroforesis en Gel Bidimensional , Hígado/metabolismo , Masculino , Espectrometría de Masas , Unión Proteica , Ratas Endogámicas Lew , Isquemia Tibia
13.
Oncol Rep ; 37(4): 2522, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28259915

RESUMEN

Following the publication of this article, an interested reader drew to our attention that three errors had occurred in the layout of the figures. In the initial and published version of Fig. 3A and B, the pictures from the Normal 0 h and Vector 0 h group were derived from the same original source due to the errors in our naming system. When the pictures were captured, these were erroneously named as 'control 1/control 2', and not 'normal/vector.' Also, in the published version of Fig. 7C, the protein expression levels of extracellular-signal-regulated kinase (ERK) and ß-actin in the MB231 cells were wrongly presented. Essentially, the band of ß-actin was a duplication of ERK. After having re-examined our original data, we realize that the Figure was compiled incorrectly, and have returned to our source data. Corrected versions of Figs. 3 and 7 are presented below. These errors did not affect the overall conclusions reported in the present study. We sincerely apologize for our mistake, and thank the reader of our article who drew this matter to our attention. Furthermore, we regret any inconvenience these mistakes have caused. [the original article was published in the Oncology Reports 32: 205-212, 2014; DOI: 10.3892/or.2014.3201].

14.
Cancer Biol Ther ; 17(4): 414-21, 2016 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-26934676

RESUMEN

Erythroid differentiation-associated gene (EDAG) is differentially expressed in normal hematopoietic progenitor/stem cells and a variety of embryonic tissues. High EDAG-1 expression is also found in human thyroid cancer cells and peripheral blood of patients with leukemia, but its functional significance was unclear. Current study aims to further clarify the expression pattern of EDAG-1 and tests its roles in proliferation and invasion of human thyroid cancer cells in vitro and in vivo. To this end, we have performed gain-of-function and loss-of-function studies to clarify how EDAG-1 regulates the proliferation, invasion, and adhesion ability of human thyroid cancer cells SW579cells. We found that overexpression of EDAG-1 promoted the proliferation, invasion, and adhesion of human thyroid cancer cells, whereas silencing of EDAG-1 reversed all these changes and reduced the tumorigenesis risk of nude mice. Mechanistically, we found that overexpression of EDAG-1 activated the MAPK/Erk and AKT signal pathways. These findings provide novel insights of the role of EDAG-1 in thyroid tumors, and may have direct clinical implication.


Asunto(s)
Inmunohistoquímica/métodos , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Proteínas Nucleares/genética , Proteína Oncogénica v-akt/metabolismo , Neoplasias de la Tiroides/genética , Animales , Proliferación Celular , Regulación hacia Abajo , Humanos , Ratones , Ratones Desnudos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Nucleares/metabolismo , Transducción de Señal , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patología , Transfección
15.
Oncotarget ; 7(5): 5664-76, 2016 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-26673822

RESUMEN

BACKGROUND: Evidence suggests that Src homologous protein phosphotyrosyl phosphatase 2 (SHP2) mutations promote cancer development in several solid tumours. In this study, we focused on the in vivo and in vitro effects of an SHP2 mutation on the breast cancer phenotype to determine whether this mutation is correlated with a malignant phenotype. METHODS: Mutant PTPN11 cDNA (D61G) was transduced into MDA-MB231 and MCF-7 cells. The effects of the D61G mutation on tumourigenesis and malignant behaviours, such as cell adhesion, proliferation, migration and invasion, were examined. Potential underlying molecular mechanisms, i.e., activation of the Gab1-Ras-Erk axis, were also examined. RESULTS: In vitro experiments revealed that tumour adhesion, proliferation, migration and invasion were significantly increased in the SHP2 D61G mutant groups. Consistently, in vivo experiments also showed that the tumour sizes and weights were increased significantly in the SHP2 D61G-MB231 group (p < 0.001) in association with tumour metastasis. Mechanistically, the PTPN11 mutation resulted in activation of the Ras-ErK pathway. The binding between Gab1 and mutant SHP2 was significantly increased. CONCLUSION: Mutant SHP2 significantly promotes tumour migration and invasion at least partially through activation of the Gab1-Ras-Erk axis. This finding could have direct implications for breast cancer therapy.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Mutación/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Animales , Apoptosis , Western Blotting , Neoplasias de la Mama/metabolismo , Adhesión Celular , Movimiento Celular , Proliferación Celular , Activación Enzimática , Femenino , Humanos , Técnicas para Inmunoenzimas , Inmunoprecipitación , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Fosforilación , Células Tumorales Cultivadas , Tirosina/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Shock ; 43(5): 497-503, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25874537

RESUMEN

The effect of granulocyte colony-stimulating factor (G-CSF) on sepsis is discussed controversially in clinical studies. We previously demonstrated that G-CSF treatment induced lipopolysaccharide (LPS) sensitization via up-regulation of LPS-binding protein (LBP). We hypothesized that the futile effect of G-CSF-treatment in sepsis might be due to its ability to up-regulate LBP. Therefore, blockade of LBP may attenuate the G-CSF-induced LPS sensitization and protect animals from polymicrobial sepsis. Endogenous LBP levels were up-regulated by pretreatment with G-CSF, and the LBP protein was blocked by administration of a specific blocking peptide-LBPK95A. Polymicrobial sepsis was induced by intraperitoneal injection of feces slurry. Rats were monitored every 3 up to 72 h to observe the survival rate. Tissue injury, bacterial infiltration, local inflammatory response, and neutrophil infiltration at 0, 2, and 12 h after the septic insult were analyzed. The survival benefit of G-CSF pretreatment was improved when combined with LBPK95A treatment (control vs. G-CSF vs. combi: 36% vs. 56% vs. 93%; P < 0.05). Combined treatment of G-CSF and LBPK95A was associated with the minimal tissue damage. Treatment with LBPK95A significantly inhibited the neutrophil infiltration without interfering with the bacterial clearance. The G-CSF-induced inflammatory sensitization effect was inhibited by LBPK95A, indicated by the decrease of cytokines expression, and the activation of nuclear factor kappa B and signal transducer and activator of transcription 3 signaling pathway. In conclusion, these results suggested that the effect of prophylactic augmentation of the host's response via G-CSF pretreatment was further enhanced by inhibition of the up-regulation of LBP.


Asunto(s)
Proteínas de Fase Aguda/química , Proteínas Portadoras/química , Factor Estimulante de Colonias de Granulocitos/química , Glicoproteínas de Membrana/química , Animales , Heces , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Humanos , Inflamación , Masculino , FN-kappa B/metabolismo , Neutrófilos/inmunología , Neutrófilos/patología , Péptidos/administración & dosificación , Ratas , Ratas Endogámicas Lew , Factor de Transcripción STAT3/metabolismo , Sepsis/inmunología , Sepsis/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Regulación hacia Arriba
17.
Mol Cancer ; 14: 10, 2015 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-25622857

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC), the most common form of primary liver cancer, is the third leading cause of cancer-related death in human. Alcohol is a known risk factor for HCC. However it is still unclear whether and how alcohol enhances the progression and metastasis of existing HCC. METHODS AND RESULTS: We first retrospectively investigated 52 HCC patients (24 alcohol-drinkers and 28 non-drinkers), and found a positive correlation between alcohol consumption and advanced Tumor-Node-Metastasis (TNM) stages, higher vessel invasion and poorer prognosis. In vitro and in vivo experiments further indicated that alcohol promoted the progression and migration/invasion of HCC. Specifically, in a 3-D tumor/endothelial co-culture system, we found that alcohol enhanced the migration/invasion of HepG2 cells and increased tumor angiogenesis. Consistently, higher expression of VEGF, MCP-1 and NF-κB was observed in HCC tissues of alcohol-drinkers. Alcohol induced the accumulation of intracellular reactive oxygen species (ROS) and the activation of NF-κB signaling in HepG2 cells. Conversely, blockage of alcohol-mediated ROS accumulation and NF-κB signaling inhibited alcohol-induced expression of VEGF and MCP-1, the tumor growth, angiogenesis and metastasis. CONCLUSION: This study suggested that chronic moderate alcohol consumption may promote the progression and metastasis of HCC; the oncogenic effect may be at least partially mediated by the ROS accumulation and NF-ĸB-dependent VEGF and MCP-1 up-regulation.


Asunto(s)
Carcinoma Hepatocelular/genética , Movimiento Celular/genética , Etanol/efectos adversos , FN-kappa B/genética , Invasividad Neoplásica/genética , Transducción de Señal/genética , Animales , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Quimiocina CCL2/genética , Progresión de la Enfermedad , Femenino , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Desnudos , Persona de Mediana Edad , Células 3T3 NIH , Neovascularización Patológica/genética , Neovascularización Patológica/patología , Estudios Retrospectivos , Factor A de Crecimiento Endotelial Vascular/genética
18.
J Immunol Res ; 2015: 187048, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26798659

RESUMEN

Sepsis and SIRS (systemic inflammatory response syndrome) belong to a severe disease complex characterized by infection and/or a whole-body inflammatory state. There is a growing body of evidence that neutrophils are actively involved in sepsis and are responsible for both release of cytokines and phagocytosis of pathogens. The neutrophil level is mainly regulated by G-CSF, a cytokine and drug, which is widely used in the septic patient with neutropenia. This review will briefly summarize the role of neutrophils and the therapeutic effect of G-CSF in sepsis. We further suggest that targeting neutrophil function to modulate the balance between innate immunity and inflammatory injury could be a worthwhile therapeutic strategy for sepsis.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Inmunidad Innata/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Sepsis/tratamiento farmacológico , Síndrome de Respuesta Inflamatoria Sistémica/tratamiento farmacológico , Proteínas de Fase Aguda/antagonistas & inhibidores , Proteínas de Fase Aguda/genética , Proteínas de Fase Aguda/inmunología , Animales , Proteínas Portadoras/antagonistas & inhibidores , Proteínas Portadoras/genética , Proteínas Portadoras/inmunología , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Factor Estimulante de Colonias de Granulocitos/genética , Factor Estimulante de Colonias de Granulocitos/inmunología , Humanos , Glicoproteínas de Membrana/antagonistas & inhibidores , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Ratones , FN-kappa B/genética , FN-kappa B/inmunología , Neutrófilos/inmunología , Neutrófilos/patología , Fagocitosis/efectos de los fármacos , Sepsis/genética , Sepsis/inmunología , Sepsis/patología , Síndrome de Respuesta Inflamatoria Sistémica/genética , Síndrome de Respuesta Inflamatoria Sistémica/inmunología , Síndrome de Respuesta Inflamatoria Sistémica/patología , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/inmunología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/inmunología
19.
Int Immunopharmacol ; 24(1): 72-9, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25479717

RESUMEN

Ischemia/reperfusion (I/R) is a pathophysiologic process that occurs during hemorrhagic shock, liver resection and liver transplantation. Baicalein, the main active ingredient of the Scutellaria root, exerts anti-inflammatory and anti-apoptotic properties in the setting of I/R injury in the heart and brain. However, the role of baicalein in liver I/R injury and its regulatory mechanisms remain poorly understood. This study was designed to evaluate the effects of baicalein in a model of liver I/R in mice and to explore the possible mechanisms. Baicalein (100mg/kg) was intraperitoneally injected 1h before warm ischemia. Pretreatment with baicalein protected against liver I/R injury, as indicated by the decreased serum aminotransferase levels and the reduced histopathologic abnormalities. Baicalein also significantly reduced cellular hepatic apoptosis in response to I/R injury. Moreover, pretreatment with baicalein significantly inhibited nuclear factor-kappa B (NF-κB) activation and the subsequent proinflammatory cytokine production, and decreased leukocyte infiltration. In vitro studies, baicalein treatment inhibited the proinflammatory cytokine production via the modulation of NF-κB signaling pathway in lipopolysaccharide-stimulated macrophages. Taken together, these results suggest that baicalein could protect against liver I/R injury via inhibition of inflammation by down-regulating NF-κB activity, and suppression of cellular hepatic apoptosis.


Asunto(s)
Antioxidantes/administración & dosificación , Flavanonas/administración & dosificación , Hígado/irrigación sanguínea , Hígado/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , Daño por Reperfusión/prevención & control , Alanina Transaminasa/sangre , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Creatinina/sangre , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Lipopolisacáridos/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Transducción de Señal/efectos de los fármacos
20.
Mediators Inflamm ; 2014: 629507, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25525303

RESUMEN

Liver dysfunction has been known to occur frequently in cases of sepsis. Excessive inflammation and apoptosis are pathological features of acute liver failure. Recent studies suggest that activation of glycogen synthase kinase- (GSK-) 3ß is involved in inflammation and apoptosis. We aimed to investigate the protective effects of GSK-3ß inhibition on polymicrobial sepsis-induced liver injury and to explore the possible mechanisms. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP), and SB216763 was used to inhibit GSK-3ß in C57BL/6 mice. GSK-3ß was activated following CLP. Administration of SB216763 decreased mortality, ameliorated liver injury, and reduced hepatic apoptosis. The inhibition of GSK-3ß also reduced leukocyte infiltration and hepatic inflammatory cytokine expression and release. Moreover, GSK-3ß inhibition suppressed the transcriptional activity of nuclear factor-kappa B (NF-κB) but enhanced the transcriptional activity of cAMP response element binding protein (CREB) in the liver. In in vitro studies, GSK-3ß inhibition reduced inflammatory cytokine production via modulation of NF-κB and CREB signaling pathways in lipopolysaccharide-stimulated macrophages. In conclusion, these findings suggest that GSK-3ß blockade protects against CLP-induced liver via inhibition of inflammation by modulating NF-κB and CREB activity and suppression of hepatic apoptosis.


Asunto(s)
Apoptosis , Glucógeno Sintasa Quinasa 3/metabolismo , Inflamación/metabolismo , Hígado/patología , Animales , Línea Celular , Citocinas/metabolismo , Ensayo de Inmunoadsorción Enzimática , Glucógeno Sintasa Quinasa 3 beta , Inmunohistoquímica , Indoles/química , Interleucina-6/metabolismo , Leucocitos/citología , Hígado/lesiones , Hígado/metabolismo , Masculino , Maleimidas/química , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Peroxidasa/metabolismo , Transducción de Señal
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