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In this work, corn straw was used as raw material, Hummers method and activation were used to adjust the graphite structure in biochar, and preparing straw based biochar (H-BCS) with ultra-high specific surface area (3441.80 m2/g), highly total pore volume (1.9859 cm3/g), and further enhanced physicochemical properties. Compared with untreated straw biochar (BCS), the specific surface area and total pore volume of H-BCS were increased by 47.24 % and 55.85 %, respectively. H-BCS showed good removal ability in subsequent experiments by using chloramphenicol (CP), hexavalent chromium (Cr6+), and crystal violet (CV) as adsorption models. In addition, the adsorption capacities of H-BCS (CP: 1396.30 mg/g, Cr6+: 218.40 mg/g, and CV: 1246.24 mg/g) are not only higher than most adsorbents, even after undergoing 5 cycles of regeneration, its adsorption capacity remains above 80 %, indicating significant potential for practical applications. In addition, we also speculated and analyzed the conjecture about the "graphite-structure regulation" during the preparation process, and finally discussed the possible mechanism during the adsorption processes. We hope this work could provide a new strategy to solve the restriction of biochar performance by further exploring the regulation of graphite structure in carbon materials.
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Carbón Orgánico , Grafito , Contaminantes Químicos del Agua , Carbón Orgánico/química , Grafito/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Adsorción , Eliminación de Residuos Líquidos/métodos , Cromo/química , Contaminación del Agua/prevención & control , Zea mays/química , Purificación del Agua/métodosRESUMEN
HLA donor-specific antibodies (DSA) elicit alloimmune responses against the graft vasculature, leading to endothelial cell (EC) activation and monocyte infiltration during antibody-mediated rejection (AMR). AMR promotes chronic inflammation and remodeling, leading to thickening of the arterial intima termed transplant vasculopathy or cardiac allograft vasculopathy (CAV) in heart transplants. Intragraft-recipient macrophages serve as a diagnostic marker in AMR; however, their polarization and function remain unclear. In this study, we utilized an in vitro Transwell coculture system to explore the mechanisms of monocyte-to-macrophage polarization induced by HLA I DSA-activated ECs. Anti-HLA I (IgG or F(ab')2) antibody-activated ECs induced the polarization of M2 macrophages with increased CD206 expression and MMP9 secretion. However, inhibition of TLR4 signaling or PSGL-1-P-selectin interactions significantly decreased both CD206 and MMP9. Monocyte adherence to Fc-P-selectin coated plates induced M2 macrophages with increased CD206 and MMP9. Moreover, Fc-receptor and IgG interactions synergistically enhanced active-MMP9 in conjunction with P-selectin. Transcriptomic analysis of arteries from DSA+CAV+ rejected cardiac allografts and multiplex-immunofluorescent staining illustrated the expression of CD68+CD206+CD163+MMP9+ M2 macrophages within the neointima of CAV-affected lesions. These findings reveal a novel mechanism linking HLA I antibody-activated endothelium to the generation of M2 macrophages which secrete vascular remodeling proteins contributing to AMR and CAV pathogenesis.
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Receptor Toll-Like 4 , Enfermedades Vasculares , Humanos , Metaloproteinasa 9 de la Matriz , Selectina-P , Macrófagos , Endotelio , Antígenos HLA , Aloinjertos , Inmunoglobulina GRESUMEN
AIMS: Programmed death-ligand 1 (PD-L1) is known to be highly expressed in various malignancies, including head and neck squamous cell carcinoma (HNSCC). We aimed to determine the prevalence of PD-L1 expression in recurrent or metastatic HNSCC (R/M HNSCC) among Chinese patients. METHODS: This multicentre, retrospective analysis of data from six centres in China included patients with R/M HNSCC treated from 9 August 2021 to 28 February 2022. PD-L1 expression in tumour tissue was assessed and represented using a combined positive score (CPS). The χ2 and Cochran-Mantel-Haenszel χ2 tests were used to compare the prevalence of different PD-L1 expression statuses according to related co-variables. RESULTS: For all 402 examined patients with R/M HNSCC, 168 cases (41.8%) had PD-L1 expression with a CPS ≥20, and 337 cases (83.8%) had PD-L1 expression with a CPS ≥1. Between the PD-L1 CPS ≥20 group and PD-L1 CPS <20 group, statistically significant differences were observed for variables of sex (p<0.001), smoking habit (p=0.0138 for non-smokers vs current smokers) and primary tumour site (p<0.001 for hypopharynx vs oral cavity and p=0.0304 for larynx vs oral cavity, respectively). CONCLUSION: PD-L1 with CPS ≥20 was expressed in about 41.8% of cases with R/M HNSCC among Chinese patients, and PD-L1 expression was significantly associated with sex, smoking history and primary tumour site. Our findings regarding the variables related to PD-L1 expression level provide insight for clinical practice and a solid basis for future research on immunotherapy in HNSCC. TRIAL REGISTRATION NUMBER: ISRCTN10570964.
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Triple-negative breast cancer (TNBC) presents significant challenges to female health owing to the lack of therapeutic targets and its poor prognosis. In recent years, in the field of molecular pathology, there has been a growing focus on the role of intra-tumoral microbial communities and metabolic alterations in tumor cells. However, the precise mechanism through which microbiota and their metabolites influence TNBC remains unclear and warrants further investigation. In this study, we analyzed the microbial community composition in various subtypes of breast cancer through 16S rRNA MiSeq sequencing of formalin-fixed, paraffin-embedded (FFPE) tissue samples. Notably, Turicibacter, a microbe associated with cancer response, exhibited a significantly higher abundance in TNBC. Similarly, mass spectrometry-based metabolomic analysis revealed substantial differences in specific metabolites, such as nutriacholic, pregnanetriol, and cortol. Furthermore, we observed significant correlations between the intra-tumoral microbiome, clinicopathological characteristics, and human epidermal growth factor receptor-2 expression(HER2). Three microbial taxa (Cytophagaceae, Conexibacteraceae, and Flavobacteriaceae) were associated with tumor-infiltrating lymphocytes(TILs), which are indicative of antitumor immunity. This study creatively utilized FFPE tissue samples to assess intra-tumoral microbial communities and their related metabolic correlations, presenting avenues for the identification of novel diagnostic biomarkers, the development of therapeutic strategies, and the early clinical diagnosis of TNBC.
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Ischemia-reperfusion injury (IRI) during orthotopic liver transplantation (OLT) contributes to graft rejection and poor clinical outcomes. The disulfide form of high mobility group box 1 (diS-HMGB1), an intracellular protein released during OLT-IRI, induces pro-inflammatory macrophages. How diS-HMGB1 differentiates human monocytes into macrophages capable of activating adaptive immunity remains unknown. We investigated if diS-HMGB1 binds toll-like receptor (TLR) 4 and TLR9 to differentiate monocytes into pro-inflammatory macrophages that activate adaptive immunity and promote graft injury and dysfunction. Assessment of 106 clinical liver tissue and longitudinal blood samples revealed that OLT recipients were more likely to experience IRI and graft dysfunction with increased diS-HMGB1 released during reperfusion. Increased diS-HMGB1 concentration also correlated with TLR4/TLR9 activation, polarization of monocytes into pro-inflammatory macrophages, and production of anti-donor antibodies. In vitro, healthy volunteer monocytes stimulated with purified diS-HMGB1 had increased inflammatory cytokine secretion, antigen presentation machinery, and reactive oxygen species production. TLR4 inhibition primarily impeded cytokine/chemokine and costimulatory molecule programs, whereas TLR9 inhibition decreased HLA-DR and reactive oxygen species production. diS-HMGB1-polarized macrophages also showed increased capacity to present antigens and activate T memory cells. In murine OLT, diS-HMGB1 treatment potentiated ischemia-reperfusion-mediated hepatocellular injury, accompanied by increased serum alanine transaminase levels. This translational study identifies the diS-HMGB1/TLR4/TLR9 axis as potential therapeutic targets in OLT-IRI recipients.
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Proteína HMGB1 , Trasplante de Hígado , Daño por Reperfusión , Humanos , Ratones , Animales , Receptor Toll-Like 9/metabolismo , Proteína HMGB1/metabolismo , Receptor Toll-Like 4/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Hígado , Daño por Reperfusión/metabolismo , Macrófagos , Citocinas/metabolismo , Apoptosis , Ratones Endogámicos C57BLRESUMEN
Solid-organ transplant recipients exhibiting HLA donor-specific Abs are at risk for graft loss due to chronic Ab-mediated rejection. HLA Abs bind HLA molecules expressed on the surface of endothelial cells (ECs) and induce intracellular signaling pathways, including the activation of the transcriptional coactivator yes-associated protein (YAP). In this study, we examined the impact of lipid-lowering drugs of the statin family on YAP localization, multisite phosphorylation, and transcriptional activity in human ECs. Exposure of sparse cultures of ECs to cerivastatin or simvastatin induced striking relocalization of YAP from the nucleus to the cytoplasm and inhibited the expression of the YAP/TEA domain DNA-binding transcription factor-regulated genes connective tissue growth factor and cysteine-rich angiogenic inducer 61. In dense cultures of ECs, statins prevented YAP nuclear import and expression of connective tissue growth factor and cysteine-rich angiogenic inducer 61 stimulated by the mAb W6/32 that binds HLA class I. Exposure of ECs to either cerivastatin or simvastatin completely blocked the migration of ECs stimulated by ligation of HLA class I. Exogenously supplied mevalonic acid or geranylgeraniol reversed the inhibitory effects of statins on YAP localization either in low-density ECs or high-density ECs challenged with W6/32. Mechanistically, cerivastatin increased the phosphorylation of YAP at Ser127, blunted the assembly of actin stress fiber, and inhibited YAP phosphorylation at Tyr357 in ECs. Using mutant YAP, we substantiated that YAP phosphorylation at Tyr357 is critical for YAP activation. Collectively, our results indicate that statins restrain YAP activity in EC models, thus providing a plausible mechanism underlying their beneficial effects in solid-organ transplant recipients.
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Células Endoteliales , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Proteínas Señalizadoras YAP , Humanos , Factor de Crecimiento del Tejido Conjuntivo/genética , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Cisteína/metabolismo , Células Endoteliales/metabolismo , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Fosforilación , Simvastatina/farmacología , Genes MHC Clase I , Proteínas Señalizadoras YAP/genéticaRESUMEN
Many cases of blindness are caused by age-related cataracts (ARCs). N6-methyladenosine (m6A)-modified circRNA widely participates in disease progression. However, the role of m6A modification of circRNA in ARC is unclear. We mined and elucidated the functions and mechanisms of key circRNAs with m6A modification involved in ARC progression. The GSE153722 dataset was used to mine m6A-mediated key circRNA. Loss-of-function assays and rescue assays were used to explore the effect and mechanism of circRNA on ARC cell proliferation and apoptosis. Has_circ_0007905 was a hypermethylated and upregulated expression in the ARC group relative to the control group both in vivo and in vitro. Silencing of has_circ_0007905 promoted proliferation and inhibited the apoptosis of HLE-B3 cells. METTL3 was upregulated in HLE-B3 cells after ARC modeling and had four binding sites with has_circ_0007905 and a mediated m6A modification of has_circ_0007905. Proliferation was significantly inhibited and apoptosis of HLE-B3 cells was facilitated by METTL3 overexpression, whereas these effects were prevented by has_circ_0007905 silencing. Silencing of has_circ_0007905 led to an alteration in the transcriptome landscape. Differentially expressed genes were mainly involved in immune-related processes and pathways. EIF4EBP1 overexpression promoted apoptosis and suppressed proliferation, and also significantly reversed effects of has_circ_0007905 silencing. Moreover, miR-6749-3p significantly decreased the luciferase activities of wild type plasmids with both of has_circ_0007905 and EIF4EBP1. MiR-6749-3p inhibitor blocked elevation in proliferation and reduced EIF4EBP1 expression and apoptosis conferred by has_circ_0007905 silencing. We reveal for the first time that the commitment of ARC progression is guided by METTL3/has_circ_0007905/miR-6749-3p/EIF4EBP1 axis, and the results provide new insights into ARC pathology.
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MicroARNs , ARN Circular , Apoptosis , Adenosina , Sitios de UniónRESUMEN
Donor-specific HLA Abs contribute to Ab-mediated rejection (AMR) by binding to HLA molecules on endothelial cells (ECs) and triggering intracellular signaling, leading to EC activation and leukocyte recruitment. The molecular mechanisms involving donor-specific HLA Ab-mediated EC activation and leukocyte recruitment remain incompletely understood. In this study, we determined whether TLRs act as coreceptors for HLA class I (HLA I) in ECs. We found that human aortic ECs express TLR3, TLR4, TLR6, and TLR10, but only TLR4 was detected on the EC surface. Consequently, we performed coimmunoprecipitation experiments to examine complex formation between HLA I and TLR4. Stimulation of human ECs with HLA Ab increased the amount of complex formation between HLA I and TLR4. Reciprocal coimmunoprecipitation with a TLR4 Ab confirmed that the crosslinking of HLA I increased complex formation between TLR4 and HLA I. Knockdown of TLR4 or MyD88 with small interfering RNAs inhibited HLA I Ab-stimulated P-selectin expression, von Willebrand factor release, and monocyte recruitment on ECs. Our results show that TLR4 is a novel coreceptor for HLA I to stimulate monocyte recruitment on activated ECs. Taken together with our previous published results, we propose that HLA I molecules form two separate signaling complexes at the EC surface, that is, with TLR4 to upregulate P-selectin surface expression and capture of monocytes to human ECs and integrin ß4 to induce mTOR-dependent firm monocyte adhesion via ICAM-1 clustering on ECs, two processes implicated in Ab-mediated rejection.
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Células Endoteliales , Molécula 1 de Adhesión Intercelular , Células Cultivadas , Endotelio Vascular/metabolismo , Antígenos HLA/metabolismo , Humanos , Integrina beta4/metabolismo , Molécula 1 de Adhesión Intercelular/metabolismo , Monocitos , Factor 88 de Diferenciación Mieloide/metabolismo , Selectina-P/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Receptor Toll-Like 3/metabolismo , Receptor Toll-Like 4/metabolismo , Receptor Toll-Like 6/metabolismo , Factor de von Willebrand/metabolismoRESUMEN
Avanafil is a phosphodiesterase type 5 inhibitor which is used to treat erectile dysfunction in men. The process-related impurities of avanafil were investigated, and four kinds of impurities in several laboratory batches with a content of 0.29-1.63% were detected by the newly developed gradient ultra-high performance liquid chromatography (UPLC). Based on the synthesis route and UPLC-MS research, the impurities are inferred as Imp-A, Imp-B, Imp-C and Imp-D. The structures of the impurities were inferred from LC-MS studies and confirmed by synthesis, followed by spectroscopic characterization such as NMR and mass spectrometry. Especially, the synthesis of Imp-D is firstly reported. The drug-related substances can be separated well by efficient and selective ultra-high performance liquid chromatography on a Waters ACQUITY HSS C18 (50 × 2.1 mm, particle size 1.8 µm) column at 35 °C, with the mobile phase consisting of ammonium formate (20 mM) and acetonitrile, and the detection at 239 nm with a DAD detector. The method was validated in terms of specificity, linearity, precision, accuracy and sensitivity, and satisfactory results were obtained. The results indicated this developed UPLC method for avanafil and the proposed synthesis mechanism can be used for quality control purposes as required by regulatory agencies to ensure the safety and efficacy of the product.
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In this study, we used a combination of chemical and biological pretreatment methods to extract cellulose from corn straw with a relative content of 92.40%. The adsorption performance and mechanism of the prepared porous carbon were investigated using synthetic dye malachite green (MG) and antibiotic tetracycline hydrochloride (TC) as adsorption models. The kinetic studies suggested that the adsorption followed the pseudo-second-order model and Bangham model. The Freundlich isotherm model fitted the adsorption data best for both MG and TC. The thermodynamic studies showed that the adsorption of MG and TC by adsorbents were spontaneous and endothermic in nature. In addition, the adsorption performance was maintained at 50% of the original value after five cycles. More importantly, this method not only improved the adsorption performance of prepared porous carbon materials but also provides a reference for the application of other lignocellulosic materials for cellulose extraction.
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Celulosa , Contaminantes Químicos del Agua , Adsorción , Carbono/química , Celulosa/química , Concentración de Iones de Hidrógeno , Cinética , Porosidad , Contaminantes Químicos del Agua/química , Zea maysRESUMEN
Objective: DNA methylation played a vital role in the progression of diabetic retinopathy. In this study, we aimed to explore the role of DNA cytosine-5-methyltransferase 1 (DNMT1) in the development of early diabetic retinopathy and its potential underlying mechanism. Methods: Eight-week-old healthy Mongolian gerbils were used to establish type 1 diabetes using streptozotocin (STZ). Alteration of weight, fasting blood glucose, density of RGCs (Tuj1-labeled), and H&E-stained retinal cross sections were applied to evaluate the diabetic retinopathy mouse model. The global DNA methylation level of the retina at different time points after STZ injection was measured using the global methylation assay. Western blot was used to detect the protein expression of DNMT1, DNA methyltransferase 3A (DNMT3A), and 3B (DNMT3B). Quantitative reverse transcription-polymerase chain reactions (qRT-PCR) and western blot were used to determine the expression of CDKN2B. Cell proliferation and cell cycle were evaluated by the MTS assay and flow cytometry. Results: STZ injection caused the increased global DNA methylation level, which reached a maximum at 6 weeks after injection. Moreover, STZ injection caused the damage of RGCs. At 6 weeks after STZ injection, the expression levels of DNMT1 and DNMT3B were significantly increased in the STZ group. DNMT1-induced DNA hypermethylation inhibited the expression of CDKN2B (a negative regulator of cell cycle). DNMT1-mediated DNA methylation facilitated RGC proliferation via regulating the expression of CDKN2B. Conclusion: DNMT1-mediated DNA methylation played an important role in STZ-induced diabetic retinopathy via modulating CDKN2B expression.
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Inhibidor p15 de las Quinasas Dependientes de la Ciclina/metabolismo , Retinopatía Diabética/metabolismo , Células Ganglionares de la Retina/metabolismo , Animales , Proliferación Celular , Biología Computacional , ADN (Citosina-5-)-Metiltransferasa 1/antagonistas & inhibidores , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , Metilación de ADN , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Retinopatía Diabética/etiología , Retinopatía Diabética/patología , Técnicas de Silenciamiento del Gen , Gerbillinae , Masculino , Células Ganglionares de la Retina/efectos de los fármacos , Células Ganglionares de la Retina/patología , Estreptozocina/toxicidadRESUMEN
BACKGROUND AND AIMS: Sterile inflammation is a major clinical concern during ischemia-reperfusion injury (IRI) triggered by traumatic events, including stroke, myocardial infarction, and solid organ transplantation. Despite high-mobility group box 1 (HMGB1) clearly being involved in sterile inflammation, its role is controversial because of a paucity of patient-focused research. APPROACH AND RESULTS: Here, we examined the role of HMGB1 oxidation states in human IRI following liver transplantation. Portal blood immediately following allograft reperfusion (liver flush; LF) had increased total HMGB1, but only LF from patients with histopathological IRI had increased disulfide-HMGB1 and induced Toll-like receptor 4-dependent tumor necrosis factor alpha production by macrophages. Disulfide HMGB1 levels increased concomitantly with IRI severity. IRI+ prereperfusion biopsies contained macrophages with hyperacetylated, lysosomal disulfide-HMGB1 that increased postreperfusion at sites of injury, paralleling increased histone acetyltransferase general transcription factor IIIC subunit 4 and decreased histone deacetylase 5 expression. Purified disulfide-HMGB1 or IRI+ blood stimulated further production of disulfide-HMGB1 and increased proinflammatory molecule and cytokine expression in macrophages through a positive feedback loop. CONCLUSIONS: These data identify disulfide-HMGB1 as a mechanistic biomarker of, and therapeutic target for, minimizing sterile inflammation during human liver IRI.
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Proteína HMGB1/metabolismo , Trasplante de Hígado/efectos adversos , Daño por Reperfusión/etiología , Citocinas/metabolismo , Disulfuros/sangre , Femenino , Técnica del Anticuerpo Fluorescente , Proteína HMGB1/sangre , Humanos , Hígado/metabolismo , Masculino , Microscopía Confocal , Persona de Mediana Edad , Monocitos/metabolismo , Daño por Reperfusión/sangre , Daño por Reperfusión/metabolismo , Donantes de TejidosRESUMEN
Ab cross-linking of HLA class I (HLA I) molecules on the surface of endothelial cells (EC) triggers proliferative and prosurvival intracellular signaling, which is implicated in the process of chronic allograft rejection, also known as transplant vasculopathy. Despite the importance of Ab-mediated rejection in transplantation, the mechanisms involved remain incompletely understood. In this study, we examined the regulation of yes-associated protein (YAP) localization, phosphorylation, and transcriptional activity in human ECs challenged with Abs that bind HLA I. In unstimulated ECs, YAP localized mainly in the cytoplasm. Stimulation of these cells with Ab W6/32 induced marked translocation of YAP to the nucleus. The nuclear import of YAP was associated with a rapid decrease in YAP phosphorylation at Ser127 and Ser397, sites targeted by LATS1/2 and with the expression of YAP-regulated genes, including connective tissue growth factor (CTGF), and cysteine-rich angiogenic inducer 61 (CYR61). Transfection of small interfering RNAs targeting YAP/TAZ blocked the migration of ECs stimulated by ligation of HLA I, indicating that YAP mediates the increase in EC migration induced by HLA I ligation. Treatment of intact ECs with Src family inhibitors induced cytoplasmic localization of YAP in unstimulated ECs and, strikingly, blocked the nuclear import of YAP induced by Ab-induced HLA I activation in these cells and the increase in the expression of the YAP-regulated genes CTGF and CYR61 induced by HLA I stimulation. Our results identify the Src/YAP axis as a key player in promoting the proliferation and migration of ECs that are critical in the pathogenesis of transplant vasculopathy.
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Proteínas Adaptadoras Transductoras de Señales/metabolismo , Aorta/citología , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Endotelio Vascular/metabolismo , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidad Clase I/metabolismo , Complicaciones Posoperatorias/inmunología , Proteínas Proto-Oncogénicas pp60(c-src)/metabolismo , Factores de Transcripción/metabolismo , Enfermedades Vasculares/inmunología , Proteínas Adaptadoras Transductoras de Señales/genética , Movimiento Celular , Proliferación Celular , Células Cultivadas , Endotelio Vascular/patología , Humanos , Isoanticuerpos/metabolismo , Trasplante de Órganos , Unión Proteica , Transporte de Proteínas , Proteínas Proto-Oncogénicas pp60(c-src)/genética , Factores de Transcripción/genética , Enfermedades Vasculares/etiología , Proteínas Señalizadoras YAPRESUMEN
Transplant recipients developing donor-specific HLA class II (HLA-II) Abs are at higher risk for Ab-mediated rejection (AMR) and transplant vasculopathy. To understand how HLA-II Abs cause AMR and transplant vasculopathy, we determined the signaling events triggered in vascular endothelial cells (EC) following Ab ligation of HLA-II molecules. HLA-II expression in EC was induced by adenoviral vector expression of CIITA or by pretreatment with TNF-α/IFN-γ. Ab ligation of class II stimulated EC proliferation and migration. Class II Ab also induced activation of key signaling nodes Src, focal adhesion kinase, PI3K, and ERK that regulated downstream targets of the mammalian target of rapamycin (mTOR) pathway Akt, p70 ribosomal S6 kinase, and S6 ribosomal protein. Pharmacological inhibitors and small interfering RNA showed the protein kinases Src, focal adhesion kinase, PI3K/Akt, and MEK/ERK regulate class II Ab-stimulated cell proliferation and migration. Treatment with rapalogs for 2 h did not affect HLA-II Ab-induced phosphorylation of ERK; instead, mTOR complex (mTORC)1 targets were dependent on activation of ERK. Importantly, suppression of mTORC2 for 24 h with rapamycin or everolimus or treatment with mTOR active-site inhibitors enhanced HLA-II Ab-stimulated phosphorylation of ERK. Furthermore, knockdown of Rictor with small interfering RNA caused overactivation of ERK while abolishing phosphorylation of Akt Ser473 induced by class II Ab. These data are different from HLA class I Ab-induced activation of ERK, which is mTORC2-dependent. Our results identify a complex signaling network triggered by HLA-II Ab in EC and indicate that combined ERK and mTORC2 inhibitors may be required to achieve optimal efficacy in controlling HLA-II Ab-mediated AMR.
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Movimiento Celular/fisiología , Proliferación Celular/fisiología , Células Endoteliales/citología , Rechazo de Injerto/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Diana Mecanicista del Complejo 2 de la Rapamicina/genética , Línea Celular , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/genética , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Células HEK293 , Humanos , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/genética , Proteína Asociada al mTOR Insensible a la Rapamicina/genética , Transducción de Señal/inmunología , Familia-src Quinasas/genética , Familia-src Quinasas/metabolismoRESUMEN
BACKGROUND: Glaucoma is hallmarked with the death of retinal neurons in the ganglion cell layer, which results in irreversible vision loss. The abnormal levels of miRNA have been associated with glaucoma. Our study purposed to explore the underlying molecule mechanism of miR-93-5p in NMDA-induced glaucoma. METHODS: The Sprague-Dawley (SD) rats were used for the establishment of glaucoma model with the injection of NMDA. Vision behavior test were performed on the glaucoma rats. MiR-93-5p expression was determined by real-time PCR. The levels of autophagy-related protein and PTEN were assessed by Western blot assays. TUNEL assay and flow cytometry were performed to analyze cell apoptosis in vivo and in vitro, respectively. And cell viability was examined by CKK-8 assay. The relationship between miR-93-5p and PTEN was confirmed by Dual-Luciferase reporter gene system. RESULTS: NMDA-induced glaucoma rats exhibited less time in the dark box, suggesting the recession of their vision. Moreover, the retinal ganglion cell (RGC) viability was reduced not only in the glaucoma rat models but also in the glaucoma RGC models. The autophagy-related protein was obviously increased in the NMDA-treated rats or RGCs. PTEN regulated the autophagy of RGCs through AKT/mTOR pathway in NMDA-treated RGCs. MiR-93-5p could target regulate PTEN negatively, and exhibit the similar effect of 3-MA on the survival of RGCs. CONCLUSION: Up-regulation of miR-93-5p binding with PTEN suppressed the autophagy of RGCs through AKT/mTOR pathway in NMDA-induced glaucoma.
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Autofagia/genética , Glaucoma/genética , MicroARNs/genética , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Células Ganglionares de la Retina/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Glaucoma/metabolismo , Glaucoma/patología , Masculino , N-Metilaspartato/farmacología , Unión Proteica , Ratas Sprague-Dawley , Células Ganglionares de la Retina/patología , Transducción de Señal , Regulación hacia ArribaRESUMEN
The signaling capacity of HLA molecules in vascular cells has been well established. Intracellular signaling and association with the coreceptor integrin ß4 has been well-studied for HLA class I. However, little is known regarding HLA class II intracellular signaling in human endothelial cells. Investigation of HLA class II has been challenging due to the loss of HLA class II expression in cultured primary cells. Herein, we describe methods for inducing expression of endogenous alleles and loci of HLA class II molecules, as well as for studying intracellular signaling. This includes siRNA knockdown of proteins and coimmunoprecipitation of putative coreceptors for HLA in primary human aortic endothelial cells.
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Células Endoteliales/metabolismo , Antígenos de Histocompatibilidad Clase II/genética , Inmunoprecipitación/métodos , Interferencia de ARN , Transducción de Señal , Transfección/métodos , Adenoviridae/genética , Western Blotting/métodos , Células Cultivadas , Expresión Génica , Vectores Genéticos/genética , Células HEK293 , Antígenos de Histocompatibilidad Clase I/análisis , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase II/análisis , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , ARN Interferente Pequeño/genéticaRESUMEN
Antibody-mediated rejection (AMR) resulting in transplant allograft vasculopathy (TAV) is the major obstacle for long-term survival of solid organ transplants. AMR is caused by donor-specific antibodies to HLA, which contribute to TAV by initiating outside-in signaling transduction pathways that elicit monocyte recruitment to activated endothelium. Mechanistic target of rapamycin (mTOR) inhibitors can attenuate TAV; therefore, we sought to understand the mechanistic underpinnings of mTOR signaling in HLA class I Ab-mediated endothelial cell activation and monocyte recruitment. We used an in vitro model to assess monocyte binding to HLA I Ab-activated endothelial cells and found mTOR inhibition reduced ezrin/radixin/moesin (ERM) phosphorylation, intercellular adhesion molecule 1 (ICAM-1) clustering, and monocyte firm adhesion to HLA I Ab-activated endothelium. Further, in a mouse model of AMR, in which C57BL/6. RAG1-/- recipients of BALB/c cardiac allografts were passively transferred with donor-specific MHC I antibodies, mTOR inhibition significantly reduced vascular injury, ERM phosphorylation, and macrophage infiltration of the allograft. Taken together, these studies indicate mTOR inhibition suppresses ERM phosphorylation in endothelial cells, which impedes ICAM-1 clustering in response to HLA class I Ab and prevents macrophage infiltration into cardiac allografts. These findings indicate a novel therapeutic application for mTOR inhibitors to disrupt endothelial cell-monocyte interactions during AMR.
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Células Endoteliales/metabolismo , Rechazo de Injerto/etiología , Trasplante de Corazón/efectos adversos , Antígenos de Histocompatibilidad Clase I/inmunología , Molécula 1 de Adhesión Intercelular/metabolismo , Monocitos/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Animales , Comunicación Celular , Células Cultivadas , Células Endoteliales/inmunología , Rechazo de Injerto/metabolismo , Rechazo de Injerto/patología , Humanos , Isoanticuerpos/efectos adversos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Monocitos/inmunologíaRESUMEN
RATIONALE: The effectiveness of transplanted bone marrow mesenchymal stem cells (MSCs) for cardiac repair has been limited; thus, strategies for optimizing stem-cell-based myocardial therapy are needed. OBJECTIVE: The present study was designed to test our central hypothesis that hypoxia-preconditioned MSCs (HP-MSCs) are more effective than MSCs cultured under ambient oxygen levels for the treatment of myocardial injury in a large-scale (N=49), long-term (9 months), nonhuman primate (Cynomolgous monkeys) investigation. METHODS AND RESULTS: MSCs were engineered to express green fluorescent protein, cultured under ambient oxygen or 0.5% oxygen (HP-MSCs) for 24 hours and then tested in the infarcted hearts of Cynomolgus monkeys (1×10(7) cells per heart). Hypoxia preconditioning increased the expression of several prosurvival/proangiogenic factors in cultured MSCs, and measurements of infarct size and left-ventricular function at day 90 after myocardial infarction were significantly more improved in monkeys treated with HP-MSCs than in monkeys treated with the control vehicle; functional improvements in normal cultured bone marrow mesenchymal stem cells-treated monkeys were not significant. HP-MSCs transplantation was also associated with increases in cardiomyocyte proliferation, vascular density, myocardial glucose uptake, and engraftment of the transplanted cells and with declines in endogenous cell apoptosis, but did not increase the occurrence of arrhythmogenic complications. CONCLUSIONS: Hypoxia preconditioning improved the effectiveness of MSCs transplantation for the treatment of myocardial infarction in nonhuman primates without increasing the occurrence of arrhythmogenic complications, which suggests that future clinical trials of HP-MSCs transplantation are warranted.
Asunto(s)
Precondicionamiento Isquémico Miocárdico/métodos , Trasplante de Células Madre Mesenquimatosas/métodos , Células Madre Mesenquimatosas/fisiología , Infarto del Miocardio/terapia , Revascularización Miocárdica , Comunicación Paracrina/fisiología , Animales , Hipoxia de la Célula/fisiología , Proliferación Celular/fisiología , Células Cultivadas , Macaca fascicularis , Masculino , Infarto del Miocardio/metabolismo , Infarto del Miocardio/fisiopatología , Primates , Trasplante Homólogo/métodosRESUMEN
BACKGROUND: The effect of liver resection on acetaminophen metabolism and whether it is affected by residual liver volume is poorly understood. METHODS: We investigated the effects of liver resection on acetaminophen metabolism in a single centre, prospective observational, case-control study of inpatients. Patients undergoing liver resection were administered therapeutic post-operative acetaminophen. Glutathione and urinary acetaminophen metabolites were measured over the first three post-operative days and compared between patients with low (Group A) and high (Group B) residual liver volume. RESULTS: 41 patients (41% female, median age 62 [IQR 53-72] years) were included. Mean urinary cysteine levels increased significantly from post-operative day 1 to 2 (578.0 mg/day 95% CI 478.9-677.1 vs. 775.4 mg/day, 95% CI 625.7-925.1; p=0.03). Group A (n=11) had significantly higher median levels of cysteine (day 1, 464.3 mg/day [IQR 355.6-582.0]; day 3, 717.6 mg/day [IQR 423.5-1104.0]) compared to Group B (n=11): day 1, 545.4 mg/day (IQR 346.9-843.5); day 3, 508.1mg/day (IQR 390.8-788.4; p=0.048). No significant difference was observed in glutathione or 5-oxoproline levels between the groups. CONCLUSION: Low residual liver volume results in altered acetaminophen metabolism, however, no evidence of glutathione deficiency was observed. Therapeutic acetaminophen is safe after major liver resection provided liver function is adequate.
Asunto(s)
Acetaminofén/sangre , Acetaminofén/orina , Cisteína/orina , Glutatión/orina , Hepatectomía/efectos adversos , Hígado/metabolismo , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Estudios de Casos y Controles , Femenino , Humanos , Hígado/cirugía , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reino UnidoRESUMEN
PURPOSE: To analyze the effect of a resolvin D1 (RvD1) analogue (RvD1a) on dendritic cell maturation, T-cell sensitization, and allograft rejection in corneal allotransplantation. METHODS: The receptor expression of RvD1 (ALX/FPR2) on bone marrow-derived dendritic cells (BMDC) was measured using quantitative real-time PCR. We determined BMDC maturation after treatment with RvD1a using ELISA to measure interleukin (IL)-12 protein expression and flow cytometry to assess the expression of CD40, major histocompatibility complex (MHC) II, CD80, and CD86. After corneal transplantation in BALB/c mice, we analyzed T-cell infiltration in the cornea and the draining lymph nodes using flow cytometry. The enzyme-linked immunospot (ELISPOT) assay was used to measure T-cell sensitization via the direct and indirect pathway. Angiogenesis and lymphangiogenesis in the cornea after transplantation were measured using immunohistochemistry. Graft opacity and survival were evaluated by slit lamp biomicroscopy. RESULTS: The receptor for RvD1, lipoxin A4/formyl peptide receptor 2 (ALX/FPR2), was expressed at a significantly lower level on immature than mature dendritic cells (DCs), and RvD1a reduced DC expression of MHC II, CD40, and IL-12 following lipopolysaccharide (LPS) stimulation. Using a murine model of corneal transplantation, RvD1a-treated hosts exhibited significantly reduced allosensitization as demonstrated by decreased frequencies of interferon-gamma-secreting T cells in the draining lymph nodes, and reduced T-cell infiltration into the grafts. Graft survival was significantly enhanced and angiogenesis at the graft site was suppressed in RvD1a-treated hosts compared with vehicle-treated hosts. CONCLUSIONS: These results suggest that RvD1 inhibits DC maturation and reduces alloimmune sensitization following transplantation, thereby establishing a novel connection between resolvin D1 and the regulation of DC-mediated, antigen-specific immunity.