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1.
FASEB J ; 38(7): e23599, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38572590

RESUMEN

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease globally. Currently, there are no effective drugs for the treatment of DN. Although several studies have reported the therapeutic potential of mesenchymal stem cells, the underlying mechanisms remain largely unknown. Here, we report that both human umbilical cord MSCs (UC-MSCs) and UC-MSC-derived exosomes (UC-MSC-exo) attenuate kidney damage, and inhibit epithelial-mesenchymal transition (EMT) and renal fibrosis in streptozotocin-induced DN rats. Strikingly, the Hedgehog receptor, smoothened (SMO), was significantly upregulated in the kidney tissues of DN patients and rats, and positively correlated with EMT and renal fibrosis. UC-MSC and UC-MSC-exo treatment resulted in decrease of SMO expression. In vitro co-culture experiments revealed that UC-MSC-exo reduced EMT of tubular epithelial cells through inhibiting Hedgehog/SMO pathway. Collectively, UC-MSCs inhibit EMT and renal fibrosis by delivering exosomes and targeting Hedgehog/SMO signaling, suggesting that UC-MSCs and their exosomes are novel anti-fibrotic therapeutics for treating DN.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Exosomas , Células Madre Mesenquimatosas , Humanos , Ratas , Animales , Nefropatías Diabéticas/metabolismo , Exosomas/metabolismo , Receptor Smoothened , Proteínas Hedgehog/metabolismo , Fibrosis , Células Madre Mesenquimatosas/metabolismo , Cordón Umbilical/metabolismo , Diabetes Mellitus/metabolismo
2.
Small ; 20(2): e2305321, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37658493

RESUMEN

2D MXene-Ti3 C2 Tx holds great promise in various electronic applications, especially for electromagnetic interference (EMI) shielding devices and supercapacitors. Ti3 C2 Tx synthesis typically involves the use of hazardous fluorine-containing chemicals that can result in the formation of inert fluoride functional groups on the surface of Ti3 C2 Tx , severely degrading its properties and posing a threat to the performance of electron transfer among electrical devices. Herein, a supercritical carbon dioxide-based ternary solution (scCO2 /DMSO/HCl) to produce fluoride-free Ti3 C2 Tx in mild conditions (via 0.5 m HCl, 20 MPa, 32 °C) is reported. The fluorine-free Ti3 C2 Tx films electrode presents an excellent gravimetric capacitance of 320 F g-1 at 2 mV s-1 in 1 m H2 SO4 . Besides, it is demonstrated that fluorine-free Ti3 C2 Tx films exhibit outstanding EMI shielding efficiency of 53.12 dB at 2.5 µm thickness. The findings offer a mild and practical approach to producing fluoride-free Ti3 C2 Tx and open opportunities for exploring MXenes' potential applications in various fields.

3.
Langmuir ; 40(26): 13550-13561, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38902967

RESUMEN

There has been a growing emphasis on facile preparation of binary heterogeneous composite materials. Leveraging the eco-friendly efficiency of supercritical CO2 technology, we achieved precise control over the influencing factors of mass transfer, enabling the accurate modulation of the resulting product morphology and properties. In the current study, CuxO/ZrOy composite materials were prepared using this technology and calcined to obtain electrode materials for the detection of cysteine (Cys). Essential comprehensive characterization techniques were employed to elucidate the heterojunction. The resulting electrode demonstrated a linear response to Cys within a concentration range of 0.5 nM to 1 µM, featuring a high sensitivity of 1035 µA·cm-2·µM-1 and a low detection limit of 97.3 nM. Thus, establishing a novel avenue for nonenzyme-based electrochemical sensors tailored for biologically active Cys detection through the implementation of a heterogeneous structure.

4.
Sensors (Basel) ; 23(8)2023 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-37112328

RESUMEN

An improved whale optimization algorithm is proposed to solve the problems of the original algorithm in indoor robot path planning, which has slow convergence speed, poor path finding ability, low efficiency, and is easily prone to falling into the local shortest path problem. First, an improved logistic chaotic mapping is applied to enrich the initial population of whales and improve the global search capability of the algorithm. Second, a nonlinear convergence factor is introduced, and the equilibrium parameter A is changed to balance the global and local search capabilities of the algorithm and improve the search efficiency. Finally, the fused Corsi variance and weighting strategy perturbs the location of the whales to improve the path quality. The improved logical whale optimization algorithm (ILWOA) is compared with the WOA and four other improved whale optimization algorithms through eight test functions and three raster map environments for experiments. The results show that ILWOA has better convergence and merit-seeking ability in the test function. In the path planning experiments, the results are better than other algorithms when comparing three evaluation criteria, which verifies that the path quality, merit-seeking ability, and robustness of ILWOA in path planning are improved.

5.
Molecules ; 28(12)2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37375257

RESUMEN

Fluorinated organic compounds have superior physicochemical properties than general organic compounds due to the strong C-F single bond; they are widely used in medicine, biology, pesticides, and materials science. In order to gain a deeper understanding of the physicochemical properties of fluorinated organic compounds, fluorinated aromatic compounds have been investigated by various spectroscopic techniques. 2-fluorobenzonitrile and 3-fluorobenzonitrile are important fine chemical intermediates and their excited state S1 and cationic ground state D0 vibrational features remain unknown. In this paper, we used two-color resonance two photon ionization (2-color REMPI) and mass analyzed threshold ionization (MATI) spectroscopy to study S1 and D0 state vibrational features of 2-fluorobenzonitrile and 3-fluorobenzonitrile. The precise excitation energy (band origin) and adiabatic ionization energy were determined to be 36,028 ± 2 cm-1 and 78,650 ± 5 cm-1 for 2-fluorobenzonitrile and 35,989 ± 2 cm-1 and 78,873 ± 5 cm-1 for 3-fluorobenzonitrile, respectively. The density functional theory (DFT) at the levels of RB3LYP/aug-cc-pvtz, TD-B3LYP/aug-cc-pvtz, and UB3LYP/aug-cc-pvtz were used to calculate the stable structures and vibrational frequencies for the ground state S0, excited state S1, and cationic ground state D0, respectively. Franck-Condon spectral simulations for transitions of S1 ← S0 and D0 ← S1 were performed based on the above DFT calculations. The theoretical and experimental results were in good agreement. The observed vibrational features in S1 and D0 states were assigned according to the simulated spectra and the comparison with structurally similar molecules. Several experimental findings and molecular features were discussed in detail.

6.
Am J Physiol Gastrointest Liver Physiol ; 322(4): G459-G471, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35234049

RESUMEN

Hepatic macrophages are involved in both pathogen clearance and immunopathogenesis. Emerging evidence demonstrates that macrophage polarization plays a critical role in hepatitis B virus (HBV)-induced immune impairment and liver pathology. However, it remains largely unknown as to how HBV infection facilitates M2 macrophage polarization. Here, a mouse HBV infection model was established by hydrodynamic injection with a vector containing 1.3-fold overlength HBV genome via the tail vein. Coculture experiments with HBV-producing HepG2.2.15 cells and macrophages were established in vitro. We found that HBV-inhibited M1 while enhancing M2 markers, which was accompanied by decreased proinflammatory tumor necrosis factor-α (TNF-α) and augmented anti-inflammatory IL-10 expression. Furthermore, both hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) secretion contributed to HBV-triggered macrophage polarization from M1 toward M2 phenotype. Mechanistically, HBsAg and HBeAg could upregulate the sirtuins 1 (SIRT1) deacetylase expression, which in turn promote deacetylation of the Notch1 intracellular domain (NICD), leading to increased Akt phosphorylation and decreased NF-κB nuclear translocation in macrophages. Our findings suggest that NICD deacetylation by SIRT1 contributes to HBsAg- and HBeAg-mediated M2 macrophage polarization, raising the possibility of targeting SIRT1/Notch1 pathway in macrophages to treat HBV immune evasion and chronic HBV infection.NEW & NOTEWORTHY This study identified a previously unrecognized molecular mechanism of HBV-mediated suppression of innate immune responses. We demonstrate that deacetylation of NICD by SIRT1 contributes to HBsAg- and HBeAg-mediated M2 macrophage polarization, which may aid in the development of new macrophage-based immunotherapy for chronic HBV infection and related diseases.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Animales , Antígenos de Superficie de la Hepatitis B/metabolismo , Antígenos e de la Hepatitis B/genética , Antígenos e de la Hepatitis B/metabolismo , Virus de la Hepatitis B , Activación de Macrófagos , Macrófagos/metabolismo , Ratones , Sirtuina 1/metabolismo
7.
Small ; 18(18): e2107393, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35363419

RESUMEN

The internal design of DNA nanostructures defines how they behave in different environmental conditions, such as endonuclease-rich or low-Mg2+ solutions. Notably, the inter-helical crossovers that form the core of such DNA objects have a major impact on their mechanical properties and stability. Importantly, crossover design can be used to optimize DNA nanostructures for target applications, especially when developing them for biomedical environments. To elucidate this, two otherwise identical DNA origami designs are presented that have a different number of staple crossovers between neighboring helices, spaced at 42- and 21- basepair (bp) intervals, respectively. The behavior of these structures is then compared in various buffer conditions, as well as when they are exposed to enzymatic digestion by DNase I. The results show that an increased number of crossovers significantly improves the nuclease resistance of the DNA origami by making it less accessible to digestion enzymes but simultaneously lowers its stability under Mg2+ -free conditions by reducing the malleability of the structures. Therefore, these results represent an important step toward rational, application-specific DNA nanostructure design.


Asunto(s)
ADN , Nanoestructuras , Estudios Cruzados , ADN/química , Nanoestructuras/química , Nanotecnología/métodos , Conformación de Ácido Nucleico
8.
Hepatology ; 74(3): 1560-1577, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33765345

RESUMEN

BACKGROUND AND AIMS: The cluster of differentiation 47 (CD47)-signal regulatory protein alpha (SIRPα) signaling pathway plays important roles in immune homeostasis and tissue inflammatory response. Activation of the Hedgehog/smoothened (SMO)/GLI family zinc finger 1 (Gli1) pathway regulates cell growth, differentiation, and immune function. However, it remains unknown whether and how the CD47-SIRPα interaction may regulate Hedgehog/SMO/Gli1 signaling in mesenchymal stem cell (MSC)-mediated immune regulation during sterile inflammatory liver injury. APPROACH AND RESULTS: In a mouse model of ischemia/reperfusion (IR)-induced sterile inflammatory liver injury, we found that adoptive transfer of MSCs increased CD47 expression and ameliorated liver IR injury. However, deletion of CD47 in MSCs exacerbated IR-induced liver damage, with increased serum ALT levels, macrophage/neutrophil infiltration, and pro-inflammatory mediators. MSC treatment augmented SIRPα, Hedgehog/SMO/Gli1, and Notch1 intracellular domain (NICD), whereas CD47-deficient MSC treatment reduced these gene expressions in IR-stressed livers. Moreover, disruption of myeloid SMO or Notch1 increased IR-triggered liver inflammation with diminished Gli1 and NICD, but enhanced NIMA related kinase 7 (NEK7) and NLR family pyrin domain containing 3 (NLRP3) activation in MSC-transferred mice. Using a MSC/macrophage co-culture system, we found that MSC CD47 and macrophage SIRPα expression were increased after LPS stimulation. The CD47-SIRPα interaction increased macrophage Gli1 and NICD nuclear translocation, whereby NICD interacted with Gli1 and regulated its target gene Dvl2 (dishevelled segment polarity protein 2), which in turn inhibited NEK7/NLRP3 activity. CONCLUSIONS: The CD47-SIRPα signaling activates the Hedgehog/SMO/Gli1 pathway, which controls NEK7/NLRP3 activity through a direct interaction between Gli1 and NICD. NICD is a coactivator of Gli1, and the target gene Dvl2 regulated by the NICD-Gli1 complex is crucial for the modulation of NLRP3-driven inflammatory response in MSC-mediated immune regulation. Our findings provide potential therapeutic targets in MSC-mediated immunotherapy of sterile inflammatory liver injury.


Asunto(s)
Antígeno CD47/inmunología , Proteínas Hedgehog/inmunología , Inflamación/inmunología , Hígado/inmunología , Células Madre Mesenquimatosas/inmunología , Receptores Inmunológicos/inmunología , Daño por Reperfusión/inmunología , Receptor Smoothened/inmunología , Proteína con Dedos de Zinc GLI1/inmunología , Alanina Transaminasa/sangre , Animales , Proteínas Dishevelled/inmunología , Inflamación/metabolismo , Inflamación/patología , Hígado/metabolismo , Hígado/patología , Macrófagos/inmunología , Trasplante de Células Madre Mesenquimatosas , Ratones , Quinasas Relacionadas con NIMA/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/inmunología , Receptor Notch1/inmunología , Daño por Reperfusión/metabolismo , Daño por Reperfusión/patología , Transducción de Señal
9.
BMC Bioinformatics ; 22(1): 14, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33413088

RESUMEN

BACKGROUND: With the development of deep learning (DL), more and more methods based on deep learning are proposed and achieve state-of-the-art performance in biomedical image segmentation. However, these methods are usually complex and require the support of powerful computing resources. According to the actual situation, it is impractical that we use huge computing resources in clinical situations. Thus, it is significant to develop accurate DL based biomedical image segmentation methods which depend on resources-constraint computing. RESULTS: A lightweight and multiscale network called PyConvU-Net is proposed to potentially work with low-resources computing. Through strictly controlled experiments, PyConvU-Net predictions have a good performance on three biomedical image segmentation tasks with the fewest parameters. CONCLUSIONS: Our experimental results preliminarily demonstrate the potential of proposed PyConvU-Net in biomedical image segmentation with resources-constraint computing.


Asunto(s)
Aprendizaje Profundo , Interpretación de Imagen Asistida por Computador , Programas Informáticos
10.
Am J Physiol Gastrointest Liver Physiol ; 318(1): G162-G173, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31604033

RESUMEN

Hepatitis B virus (HBV) exploits multiple strategies to evade host immune surveillance. Programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) signaling plays a critical role in regulating T cell homeostasis. However, it remains largely unknown as to how HBV infection elevates PD-L1 expression in hepatocytes. A mouse model of HBV infection was established by hydrodynamic injection with a vector containing 1.3-fold overlength HBV genome (pHBV1.3) via the tail vein. Coculture experiments with HBV-expressing hepatoma cells and Jurkat T cells were established in vitro. We observed significant decrease in the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and increase in ß-catenin/PD-L1 expression in liver tissues from patients with chronic hepatitis B and mice subjected to pHBV1.3 hydrodynamic injection. Mechanistically, decrease in PTEN enhanced ß-catenin/c-Myc signaling and PD-L1 expression in HBV-expressing hepatoma cells, which in turn augmented PD-1 expression, lowered IL-2 secretion, and induced T cell apoptosis. However, ß-catenin disruption inhibited PTEN-mediated PD-L1 expression, which was accompanied by decreased PD-1 expression, and increased IL-2 production in T cells. Luciferase reporter assays revealed that c-Myc stimulated transcriptional activity of PD-L1. In addition, HBV X protein (HBx) and HBV polymerase (HBp) contributed to PTEN downregulation and ß-catenin/PD-L1 upregulation. Strikingly, PTEN overexpression in hepatocytes inhibited ß-catenin/PD-L1 signaling and promoted HBV clearance in vivo. Our findings suggest that HBV-triggered PTEN/ß-catenin/c-Myc signaling via HBx and HBp enhances PD-L1 expression, leading to inhibition of T cell response, and promotes HBV immune evasion.NEW & NOTEWORTHY This study demonstrates that during HBV infection, HBV can increase PD-L1 expression via PTEN/ß-catenin/c-Myc signaling pathway, which in turn inhibits T cell response and ultimately promotes HBV immune evasion. Targeting this signaling pathway is a potential strategy for immunotherapy of chronic hepatitis B.


Asunto(s)
Antígeno B7-H1/metabolismo , Virus de la Hepatitis B/metabolismo , Hepatitis B Crónica/metabolismo , Hepatocitos/enzimología , Evasión Inmune , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Linfocitos T/enzimología , beta Catenina/metabolismo , Animales , Técnicas de Cocultivo , Modelos Animales de Enfermedad , Productos del Gen pol/genética , Productos del Gen pol/metabolismo , Células Hep G2 , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/inmunología , Hepatitis B Crónica/virología , Hepatocitos/inmunología , Hepatocitos/virología , Humanos , Células Jurkat , Activación de Linfocitos , Masculino , Ratones Endogámicos BALB C , Transducción de Señal , Linfocitos T/inmunología , Linfocitos T/virología , Transactivadores/genética , Transactivadores/metabolismo , Proteínas Reguladoras y Accesorias Virales
11.
Hepatology ; 70(5): 1714-1731, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31063235

RESUMEN

The Hippo pathway, an evolutionarily conserved protein kinase cascade, tightly regulates cell growth and survival. Activation of yes-associated protein (YAP), a downstream effector of the Hippo pathway, has been shown to modulate tissue inflammation. However, it remains unknown as to whether and how the Hippo-YAP signaling may control NLR family pyrin domain containing 3 (NLRP3) activation in mesenchymal stem cell (MSC)-mediated immune regulation during liver inflammation. In a mouse model of ischemia/reperfusion (IR)-induced liver sterile inflammatory injury, we found that adoptive transfer of MSCs reduced hepatocellular damage, shifted macrophage polarization from M1 to M2 phenotype, and diminished inflammatory mediators. MSC treatment reduced mammalian Ste20-like kinase 1/2 and large tumor suppressor 1 phosphorylation but augmented YAP and ß-catenin expression with increased prostaglandin E2 production in ischemic livers. However, disruption of myeloid YAP or ß-catenin in MSC-transferred mice exacerbated IR-triggered liver inflammation, enhanced NLRP3/caspase-1 activity, and reduced M2 macrophage phenotype. Using MSC/macrophage coculture system, we found that MSCs increased macrophage YAP and ß-catenin nuclear translocation. Importantly, YAP and ß-catenin colocalize in the nucleus while YAP interacts with ß-catenin and regulates its target gene X-box binding protein 1 (XBP1), leading to reduced NLRP3/caspase-1 activity after coculture. Moreover, macrophage YAP or ß-catenin deficiency augmented XBP1/NLRP3 while XBP1 deletion diminished NLRP3/caspase-1 activity. Increasing NLRP3 expression reduced M2 macrophage arginase1 but augmented M1 macrophage inducible nitric oxide synthase expression accompanied by increased interleukin-1ß release. Conclusion: MSCs promote macrophage Hippo pathway, which in turn controls NLRP3 activation through a direct interaction between YAP and ß-catenin and regulates XBP1-mediated NLRP3 activation, leading to reprograming macrophage polarization toward an anti-inflammatory M2 phenotype. Moreover, YAP functions as a transcriptional coactivator of ß-catenin in MSC-mediated immune regulation. Our findings suggest a therapeutic target in MSC-mediated immunotherapy of liver sterile inflammatory injury.


Asunto(s)
Hígado/irrigación sanguínea , Células Madre Mesenquimatosas/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/fisiología , Daño por Reperfusión/inmunología , Transducción de Señal/fisiología , Proteínas Adaptadoras Transductoras de Señales/fisiología , Animales , Proteínas de Ciclo Celular/fisiología , Células Cultivadas , Macrófagos/fisiología , Ratones , Proteínas Señalizadoras YAP
12.
Hepatology ; 69(3): 974-992, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30180281

RESUMEN

Hepatitis B virus (HBV) is a major risk factor for the development and progression of hepatocellular carcinoma. It has been reported that viral infection can interfere with cellular microRNA (miRNA) expression and participate in the pathogenesis of oncogenicity. Here, we report that decreasing levels of the expression of the miRNA miR-192-3p is associated with rising levels of HBV DNA in the serum of HBV patients. We revealed that HBV infection repressed the expression of miR-192-3p through hepatitis B x protein interaction with c-myc. We further showed that miR-192-3p was repressed by HBV transfection in vitro and in a mouse model, leading to cellular autophagy. Using an miRNA target prediction database miRBase, we identified X-linked inhibitor of apoptosis protein (XIAP) as a target gene of miR-192-3p and demonstrated that miR-192-3p directly targeted the XIAP 3'-untranslated region of XIAP messenger RNA. Importantly, we discovered that HBV promoted autophagy through miR-192-3p-XIAP axis and that this process was important for HBV replication in vitro and in vivo. We demonstrated that miR-192-3p functioned through the nuclear factor kappa B signaling pathway to inhibit autophagy, thereby reducing HBV replication. Conclusions: Our findings indicate that miR-192-3p is a regulator of HBV infection and may play a potential role in hepatocellular carcinoma. It may also serve as a biomarker or therapeutic target for HBV patients.


Asunto(s)
Autofagia/fisiología , Virus de la Hepatitis B/fisiología , Proteínas Inhibidoras de la Apoptosis/fisiología , MicroARNs/fisiología , FN-kappa B/fisiología , Transducción de Señal , Replicación Viral , Animales , Células Cultivadas , Ratones
13.
FASEB J ; 33(10): 11180-11193, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31295018

RESUMEN

Liver fibrosis is an important pathologic process in injured liver tissues. A protein kinase, receptor-interacting protein (RIP)3, plays a crucial role in mediating different diseases. However, the role of RIP3 in macrophages in liver fibrosis has not yet been studied. In our study, we found that RIP3 expression was up-regulated in liver tissues and macrophages of humans and mice with liver fibrosis. Absence of RIP3 in macrophages could alleviate inflammation and macrophage or neutrophil accumulation in mice after carbon tetrachloride (CCl4) or bile duct ligation (BDL) treatment. Importantly, RIP3 deficiency in macrophages could decrease CCl4-induced and BDL-induced liver fibrosis in mice. Moreover, RIP3 deficiency could inhibit the TLR4-NF-κB pathway through suppressing Rho-associated coiled-coil containing protein kinase (ROCK)1 in macrophages. To explore the connection of ROCK1 and RIP3 in macrophages of mice with liver fibrosis in vivo, ROCK1-overexpressed macrophages were infused to RIP3-deficient mice, which resulted in increased inflammation and liver fibrosis. In conclusion, our findings suggest that RIP3 plays a crucial proinflammatory role in liver fibrosis by regulating the ROCK1-TLR4-NF-κB signaling pathway in macrophages and therefore may be a potential therapeutic target for immune-mediated liver fibrosis.-Wei, S., Zhou, H., Wang, Q., Zhou, S., Li, C., Liu, R., Qiu, J., Shi, C., Lu, L. RIP3 deficiency alleviates liver fibrosis by inhibiting ROCK1-TLR4-NF-κB pathway in macrophages.


Asunto(s)
Hígado/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/deficiencia , Animales , Humanos , Proteínas I-kappa B/metabolismo , Inflamación/metabolismo , Cirrosis Hepática/metabolismo , Macrófagos/metabolismo , Masculino , Ratones Endogámicos C57BL , Transducción de Señal , Receptor Toll-Like 4/metabolismo , Quinasas Asociadas a rho/metabolismo
14.
Hepatology ; 67(3): 1041-1055, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29024000

RESUMEN

Notch signaling plays an emerging role in the regulation of immune cell development and function during inflammatory response. Activation of the ras homolog gene family member A/Rho-associated protein kinase (ROCK) pathway promotes leukocyte accumulation in tissue injury. However, it remains unknown whether Notch signaling regulates ras homolog gene family member A/ROCK-mediated immune responses in liver ischemia and reperfusion (IR) injury. This study investigated intracellular signaling pathways regulated by Notch receptors in the IR-stressed liver and in vitro. In a mouse model of IR-induced liver inflammatory injury, we found that mice with myeloid-specific Notch1 knockout showed aggravated hepatocellular damage, with increased serum alanine aminotransferase levels, hepatocellular apoptosis, macrophage/neutrophil trafficking, and proinflammatory mediators compared to Notch1-proficient controls. Unlike in the controls, myeloid Notch1 ablation diminished hairy and enhancer of split-1 (Hes1) and augmented c-Jun N-terminal kinase (JNK)/stress-activated protein kinase-associated protein 1 (JSAP1), JNK, ROCK1, and phosphatase and tensin homolog (PTEN) activation in ischemic livers. Disruption of JSAP1 in myeloid-specific Notch1 knockout livers improved hepatocellular function and reduced JNK, ROCK1, PTEN, and toll-like receptor 4 activation. Moreover, ROCK1 knockdown inhibited PTEN and promoted Akt, leading to depressed toll-like receptor 4. In parallel in vitro studies, transfection of lentivirus-expressing Notch1 intracellular domain promoted Hes1 and inhibited JSAP1 in lipopolysaccharide-stimulated bone marrow-derived macrophages. Hes1 deletion enhanced JSAP1/JNK activation, whereas clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9-mediated JSAP1 knockout diminished ROCK1/PTEN and toll-like receptor 4 signaling. CONCLUSION: Myeloid Notch1 deficiency activates the ras homolog gene family member A/ROCK pathway and exacerbates hepatocellular injury by inhibiting transcriptional repressor Hes1 and inducing scaffold protein JSAP1 in IR-triggered liver inflammation; our findings underscore the crucial role of the Notch-Hes1 axis as a novel regulator of innate immunity-mediated inflammation and imply the therapeutic potential for the management of organ IR injury in transplant recipients. (Hepatology 2018;67:1041-1055).


Asunto(s)
Hígado/patología , Receptor Notch1/genética , Daño por Reperfusión/metabolismo , Proteínas de Unión al GTP rho/metabolismo , Quinasas Asociadas a rho/metabolismo , Animales , Apoptosis/genética , Western Blotting , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Hígado/metabolismo , Macrófagos/metabolismo , Ratones , Ratones Noqueados , Especies Reactivas de Oxígeno , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor Notch1/metabolismo , Transducción de Señal , Proteína de Unión al GTP rhoA
15.
Liver Transpl ; 23(6): 813-825, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28152578

RESUMEN

The phosphatase and tensin homolog (PTEN) deleted on chromosome 10 plays an important role in regulating T cell activation during inflammatory response. Activation of ß-catenin is crucial for maintaining immune homeostasis. This study investigates the functional roles and molecular mechanisms by which PTEN-ß-catenin signaling promotes regulatory T cell (Treg) induction in a mouse model of liver ischemia/reperfusion injury (IRI). We found that mice with myeloid-specific phosphatase and tensin homolog knockout (PTENM-KO ) exhibited reduced liver damage as evidenced by decreased levels of serum alanine aminotransferase, intrahepatic macrophage trafficking, and proinflammatory mediators compared with the PTEN-proficient (floxed phosphatase and tensin homolog [PTENFL/FL ]) controls. Disruption of myeloid PTEN-activated b-catenin promoted peroxisome proliferator-activated receptor gamma (PPARγ)-mediated Jagged-1/Notch signaling and induced forkhead box P3 (FOXP3)1 Tregs while inhibiting T helper 17 cells. However, blocking of Notch signaling by inhibiting γ-secretase reversed myeloid PTEN deficiency-mediated protection in ischemia/reperfusion-triggered liver inflammation with reduced FOXP3+ and increased retinoid A receptor-related orphan receptor gamma t-mediated interleukin 17A expression in ischemic livers. Moreover, knockdown of ß-catenin or PPARγ in PTEN-deficient macrophages inhibited Jagged-1/Notch activation and reduced FOXP3+ Treg induction, leading to increased proinflammatory mediators in macrophage/T cell cocultures. In conclusion, our findings demonstrate that PTEN-ß-catenin signaling is a novel regulator involved in modulating Treg development and provides a potential therapeutic target in liver IRI. Liver Transplantation 23 813-825 2017 AASLD.


Asunto(s)
Hígado/metabolismo , Fosfohidrolasa PTEN/metabolismo , Daño por Reperfusión/metabolismo , Linfocitos T Reguladores/metabolismo , beta Catenina/metabolismo , Alanina Transaminasa/metabolismo , Animales , Técnicas de Cocultivo , Factores de Transcripción Forkhead/metabolismo , Homeostasis , Inflamación , Hígado/patología , Trasplante de Hígado , Activación de Linfocitos , Macrófagos/metabolismo , Ratones , Ratones Noqueados , Microscopía Fluorescente , PPAR gamma/metabolismo , Fosfohidrolasa PTEN/genética , Transducción de Señal , Bazo/metabolismo , Linfocitos T/citología
16.
Hepatology ; 64(5): 1683-1698, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27474884

RESUMEN

Heat shock transcription factor 1 (HSF1) has been implicated in the differential regulation of cell stress and disease states. ß-catenin activation is essential for immune homeostasis. However, little is known about the role of macrophage HSF1-ß-catenin signaling in the regulation of NLRP3 inflammasome activation during ischemia/reperfusion (I/R) injury (IRI) in the liver. This study investigated the functions and molecular mechanisms by which HSF1-ß-catenin signaling influenced NLRP3-mediated innate immune response in vivo and in vitro. Using a mouse model of IR-induced liver inflammatory injury, we found that mice with a myeloid-specific HSF1 knockout (HSF1M-KO ) displayed exacerbated liver damage based on their increased serum alanine aminotransferase levels, intrahepatic macrophage/neutrophil trafficking, and proinflammatory interleukin (IL)-1ß levels compared to the HSF1-proficient (HSF1FL/FL ) controls. Disruption of myeloid HSF1 markedly increased transcription factor X-box-binding protein (XBP1), NLR family, pyrin domain-containing 3 (NLRP3), and cleaved caspase-1 expression, which was accompanied by reduced ß-catenin activity. Knockdown of XBP1 in HSF1-deficient livers using a XBP1 small interfering RNA ameliorated hepatocellular functions and reduced NLRP3/cleaved caspase-1 and IL-1ß protein levels. In parallel in vitro studies, HSF1 overexpression increased ß-catenin (Ser552) phosphorylation and decreased reactive oxygen species (ROS) production in bone-marrow-derived macrophages. However, myeloid HSF1 ablation inhibited ß-catenin, but promoted XBP1. Furthermore, myeloid ß-catenin deletion increased XBP1 messenger RNA splicing, whereas a CRISPR/CRISPR-associated protein 9-mediated XBP1 knockout diminished NLRP3/caspase-1. CONCLUSION: The myeloid HSF1-ß-catenin axis controlled NLRP3 activation by modulating the XBP1 signaling pathway. HSF1 activation promoted ß-catenin, which, in turn, inhibited XBP1, leading to NLRP3 inactivation and reduced I/R-induced liver injury. These findings demonstrated that HSF1/ß-catenin signaling is a novel regulator of innate immunity in liver inflammatory injury and implied the therapeutic potential for management of sterile liver inflammation in transplant recipients. (Hepatology 2016;64:1683-1698).


Asunto(s)
Proteínas de Unión al ADN/fisiología , Inflamasomas/fisiología , Hígado/irrigación sanguínea , Proteína con Dominio Pirina 3 de la Familia NLR/fisiología , Daño por Reperfusión/etiología , Factores de Transcripción/fisiología , beta Catenina/fisiología , Animales , Factores de Transcripción del Choque Térmico , Ratones , Transducción de Señal
17.
Korean J Physiol Pharmacol ; 20(5): 507-14, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27610037

RESUMEN

Although 3D-complex fractionated atrial electrogram (CFAE) mapping is useful in radiofrequency catheter ablation for persistent atrial fibrillation (AF), the directions and configuration of the bipolar electrodes may affect the electrogram. This study aimed to compare the spatial reproducibility of CFAE by changing the catheter orientations and electrode distance in an in-silico left atrium (LA). We conducted this study by importing the heart CT image of a patient with AF into a 3D-homogeneous human LA model. Electrogram morphology, CFAE-cycle lengths (CLs) were compared for 16 different orientations of a virtual bipolar conventional catheter (conv-cath: size 3.5 mm, inter-electrode distance 4.75 mm). Additionally, the spatial correlations of CFAE-CLs and the percentage of consistent sites with CFAE-CL<120 ms were analyzed. The results from the conv-cath were compared with that obtained using a mini catheter (mini-cath: size 1 mm, inter-electrode distance 2.5 mm). Depending on the catheter orientation, the electrogram morphology and CFAE-CLs varied (conv-cath: 11.5±0.7% variation, mini-cath: 7.1±1.2% variation), however the mini-cath produced less variation of CFAE-CL than conv-cath (p<0.001). There were moderate spatial correlations among CFAE-CL measured at 16 orientations (conv-cath: r=0.3055±0.2194 vs. mini-cath: 0.6074±0.0733, p<0.001). Additionally, the ratio of consistent CFAE sites was higher for mini catheter than conventional one (38.3±4.6% vs. 22.3±1.4%, p<0.05). Electrograms and CFAE distribution are affected by catheter orientation and electrode configuration in the in-silico LA model. However, there was moderate spatial consistency of CFAE areas, and narrowly spaced bipolar catheters were less influenced by catheter direction than conventional catheters.

18.
Biochem Biophys Res Commun ; 466(2): 173-9, 2015 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-26342798

RESUMEN

Mesenchymal stem cells (MSCs) have been shown to have an immunomodulatory capability and clinical potential in immune diseases. However, it is unknown how MSCs may affect immunity in liver injury. This study was designed to explore the effect of bone marrow-derived MSCs (BM-MSCs) on hepatic natural killer (NK) cells in polyinosinic-polycytidylic acid (PolyI:C)-induced liver injury. Unlike in controls, adoptive transfer of BM-MSCs in mice ameliorated PolyI:C-induced liver injury, as shown by lower alanine aminotransferase levels and decreased lymphocyte infiltration in the liver. Importantly, BM-MSCs suppress NK cell accumulation and activation in the liver, which plays an important role in PolyI:C-induced liver injury. Furthermore, NK cells co-cultured with BM-MSCs reduced expression of sphingosine-1-phosphate receptor type 5 (S1PR5), an important receptor required for NK cell trafficking in vivo. BM-MSC administration suppressed the elevation of expression of S1PR5 in the liver induced by PolyI:C injection. Accordingly, BM-MSCs inhibited the chemotactic activity of NK cells induced by sphingosine-1-phosphate (S1P, the ligand of S1PR5). Our results provide an additional mechanism for the immunosuppressive effect of BM-MSCs on NK cells, which further supports the therapeutic potential of BM-MSCs in immune-mediated disorders, including those in which NK cells play a major role.


Asunto(s)
Células Asesinas Naturales/citología , Hígado/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Poli I-C/farmacología , Animales , Células Cultivadas , Ratones
19.
J Environ Sci (China) ; 26(11): 2355-61, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25458692

RESUMEN

Ni was effectively recovered from spent electroless nickel (EN) plating baths by forming a nano-nickel coated activated carbon composite. With the aid of ultrasonication, melamine-formaldehyde-tetraoxalyl-ethylenediamine chelating resins were grafted on activated carbon (MFT/AC). PdCl2 sol was adsorbed on MFT/AC, which was then immersed in spent electroless nickel plating bath; then nano-nickel could be reduced by ascorbic acid to form a nano-nickel coating on the activated carbon composite (Ni/AC) in situ. The materials present were carefully examined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, X-ray photoelectron spectroscopy and electrochemistry techniques. The resins were well distributed on the inside and outside surfaces of activated carbon with a size of 120 ± 30 nm in MFT/AC, and a great deal of nano-nickel particles were evenly deposited with a size of 3.8 ± 1.1 nm in Ni/MFT. Moreover, Ni/AC was successfully used as a catalyst for ultrasonic degradation of 2,6-dichlorophenol.


Asunto(s)
Carbono/química , Clorofenoles/química , Nanotecnología , Níquel/química , Ultrasonido , Microscopía Electrónica de Rastreo
20.
Sci Rep ; 14(1): 4066, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38374193

RESUMEN

Present studies show that steel fibres can improve the bond of steel bar in steel fibre reinforced concrete (SFRC) with a correlation to the fibre factor and the fibre distribution uniformity. As a foundation of high-flowability SFRC working together with 400 MPa grade hot-rolled ribbed (HRB400) steel bar in reinforced structures, the bond between them was evaluated through a series of pull-out testing on 48 specimens with a central arranged steel bar. The bond behaviours of steel bar were estimated with a constant bond length of 5d (d is the diameter of steel bar) embedded in high-flowability SFRC, the main research parameters included the ingot mill steel fibres with a fibre volume fraction varied from 0.8 to 2.0%, the strength grade C40 and C50 of SFRC or referenced conventional concrete, and the diameter of steel bars varied from 14 to 20 mm. Results showed that the high-flowability SFRC compacted with a slight vibration is beneficial to improve the bond failure pattern since steel fibres effectively eliminate the crack appeared on the SFRC blocks during the pulling out of steel bar, leading to all specimens failed with the steel bar pull out of SFRC blocks. The bond strength was dominant by the SFRC strength, and obviously strengthened with the increase of fibre volume fraction, while the peak-slip was slightly influenced by the diameter of steel bar. By conducting analyses of test data, equations for calculating the bond strength and the peak-slip are proposed accounting for the effect of steel fibres. Then the predicting method for the anchorage length is suggested linking with different design codes for concrete structures. Compared with test results of this study, a little shorter anchorage length of steel bar in SFRC is obtained from the specification of Chinese code JGJ/T46, which should be noticed to ensure a rational anchorage of ribbed steel bar in SFRC with ingot mill steel fibres.

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