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1.
Physiol Rev ; 103(3): 2321-2347, 2023 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-36796098

RESUMEN

The local environment surrounding airway smooth muscle (ASM) cells has profound effects on the physiological and phenotypic properties of ASM tissues. ASM is continually subjected to the mechanical forces generated during breathing and to the constituents of its surrounding extracellular milieu. The smooth muscle cells within the airways continually modulate their properties to adapt to these changing environmental influences. Smooth muscle cells connect to the extracellular cell matrix (ECM) at membrane adhesion junctions that provide mechanical coupling between smooth muscle cells within the tissue. Membrane adhesion junctions also sense local environmental signals and transduce them to cytoplasmic and nuclear signaling pathways in the ASM cell. Adhesion junctions are composed of clusters of transmembrane integrin proteins that bind to ECM proteins outside the cell and to large multiprotein complexes in the submembranous cytoplasm. Physiological conditions and stimuli from the surrounding ECM are sensed by integrin proteins and transduced by submembranous adhesion complexes to signaling pathways to the cytoskeleton and nucleus. The transmission of information between the local environment of the cells and intracellular processes enables ASM cells to rapidly adapt their physiological properties to modulating influences in their extracellular environment: mechanical and physical forces that impinge on the cell, ECM constituents, local mediators, and metabolites. The structure and molecular organization of adhesion junction complexes and the actin cytoskeleton are dynamic and constantly changing in response to environmental influences. The ability of ASM to rapidly accommodate to the ever-changing conditions and fluctuating physical forces within its local environment is essential for its normal physiological function.


Asunto(s)
Contracción Muscular , Músculo Liso , Contracción Muscular/fisiología , Músculo Liso/metabolismo , Miocitos del Músculo Liso , Fenotipo , Integrinas/metabolismo
2.
Molecules ; 29(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38731520

RESUMEN

Graphitic carbon nitride (g-C3N4), recognized for its considerable potential as a heterogeneous photocatalyst in water splitting, has attracted extensive research interest. By using density functional theory (DFT) calculations, the regulatory role of p-block metal (PM) single atoms on the photocatalytic activity of g-C3N4 in overall water splitting was systematically explored. The incorporation of PM atoms (Ge, Sn and Pb) led to a reduction in the overpotentials required for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). Combined with the electronic structures analysis via hybrid functional, it was found that the introduction of Ge, Sn or Pb optimizes the positions of the valence band maximum (VBM) and the conduction band minimum (CBM), providing a robust driving force for HER and ensuring substantial driving force for OER. Meanwhile, the presence of these three PMs induces the spatial separation of VBM and CBM, inhibiting the recombination of carriers. These findings have significant implications for the design and preparation of efficient photocatalysts.

3.
Respir Res ; 24(1): 157, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37316833

RESUMEN

BACKGROUND: The recruitment of the actin-regulatory proteins cortactin and profilin-1 (Pfn-1) to the membrane is important for the regulation of actin cytoskeletal reorganization and smooth muscle contraction. Polo-like kinase 1 (Plk1) and the type III intermediate filament protein vimentin are involved in smooth muscle contraction. Regulation of complex cytoskeletal signaling is not entirely elucidated. The aim of this study was to evaluate the role of nestin (a type VI intermediate filament protein) in cytoskeletal signaling in airway smooth muscle. METHODS: Nestin expression in human airway smooth muscle (HASM) was knocked down by specific shRNA or siRNA. The effects of nestin knockdown (KD) on the recruitment of cortactin and Pfn-1, actin polymerization, myosin light chain (MLC) phosphorylation, and contraction were evaluated by cellular and physiological approaches. Moreover, we assessed the effects of non-phosphorylatable nestin mutant on these biological processes. RESULTS: Nestin KD reduced the recruitment of cortactin and Pfn-1, actin polymerization, and HASM contraction without affecting MLC phosphorylation. Moreover, contractile stimulation enhanced nestin phosphorylation at Thr-315 and the interaction of nestin with Plk1. Nestin KD also diminished phosphorylation of Plk1 and vimentin. The expression of T315A nestin mutant (alanine substitution at Thr-315) reduced the recruitment of cortactin and Pfn-1, actin polymerization, and HASM contraction without affecting MLC phosphorylation. Furthermore, Plk1 KD diminished nestin phosphorylation at this residue. CONCLUSIONS: Nestin is an essential macromolecule that regulates actin cytoskeletal signaling via Plk1 in smooth muscle. Plk1 and nestin form an activation loop during contractile stimulation.


Asunto(s)
Actinas , Cortactina , Humanos , Nestina/genética , Vimentina , Cortactina/genética , Citoesqueleto
4.
Nano Lett ; 21(8): 3680-3689, 2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33596656

RESUMEN

Efficient endosomal escape is the most essential but challenging issue for siRNA drug development. Herein, a series of quaternary ammonium-based amphiphilic triblock polymers harnessing an elaborately tailored pH-sensitive hydrophobic core were synthesized and screened. Upon incubating in an endosomal pH environment (pH 6.5-6.8), mPEG45-P(DPA50-co-DMAEMA56)-PT53 (PDDT, the optimized polymer) nanomicelles (PDDT-Ms) and PDDT-Ms/siRNA polyplexes rapidly disassembled, leading to promoted cytosolic release of internalized siRNA and enhanced silencing activity evident from comprehensive analysis of the colocalization and gene silencing using a lysosomotropic agent (chloroquine) and an endosomal trafficking inhibitor (bafilomycin A1). In addition, PDDT-Ms/siPLK1 dramatically repressed tumor growth in both HepG2-xenograft and highly malignant patient-derived xenograft models. PDDT-Ms-armed siPD-L1 efficiently blocked the interaction of PD-L1 and PD-1 and restored immunological surveillance in CT-26-xenograft murine model. PDDT-Ms/siRNA exhibited ideal safety profiles in these assays. This study provides guidelines for rational design and optimization of block polymers for efficient endosomal escape of internalized siRNA and cancer therapy.


Asunto(s)
Endosomas , Polímeros , Animales , Línea Celular Tumoral , Silenciador del Gen , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Ratones , ARN Interferente Pequeño/genética
5.
Am J Physiol Lung Cell Mol Physiol ; 321(1): L102-L115, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-34009050

RESUMEN

Furin is a proprotein convertase that regulates the activation and the inactivation of multiple proteins including matrix metalloproteinases, integrins, and cytokines. It is a serine endoprotease that localizes to the plasma membrane and can be secreted into the extracellular space. The role of furin in regulating inflammation in isolated canine airway smooth muscle tissues was investigated. The treatment of airway tissues with recombinant furin (rFurin) inhibited the activation of Akt and eotaxin secretion induced by IL-13, and it prevented the IL-13-induced suppression of smooth muscle myosin heavy chain expression. rFurin promoted a differentiated phenotype by activating ß1-integrin proteins and stimulating the activation of the adhesome proteins vinculin and paxillin by talin. Activated paxillin induced the binding of Akt to ß-parvin IPP [integrin-linked kinase (ILK), PINCH, parvin] complexes, which inhibits Akt activation. Treatment of tissues with a furin inhibitor or the depletion of endogenous furin using shRNA resulted in Akt activation and inflammatory responses similar to those induced by IL-13. Furin inactivation or IL-13 caused talin cleavage and integrin inactivation, resulting in the inactivation of vinculin and paxillin. Paxillin inactivation resulted in the coupling of Akt to α-parvin IPP complexes, which catalyze Akt activation and an inflammatory response. The results demonstrate that furin inhibits inflammation in airway smooth muscle induced by IL-13 and that the anti-inflammatory effects of furin are mediated by activating integrin proteins and integrin-associated signaling complexes that regulate Akt-mediated pathways to the nucleus. Furin may have therapeutic potential for the treatment of inflammatory conditions of the lungs and airways.


Asunto(s)
Furina/farmacología , Inflamación/prevención & control , Integrinas/metabolismo , Interleucina-13/toxicidad , Músculo Liso/efectos de los fármacos , Tráquea/efectos de los fármacos , Animales , Perros , Humanos , Inflamación/etiología , Inflamación/metabolismo , Inflamación/patología , Integrinas/genética , Músculo Liso/inmunología , Músculo Liso/metabolismo , Músculo Liso/patología , Transducción de Señal , Tráquea/inmunología , Tráquea/metabolismo , Tráquea/patología
6.
Wound Repair Regen ; 29(2): 335-337, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33428268

RESUMEN

Ongoing investigations in wound repair bring new opportunities and challenges for creating novel composite engineered biomaterials. Efforts have been directed toward using different combinations of biomaterials with the goal of providing an ideal biomimetic substitute for native tissue. A universal formula using collagen, fibroin and a synthetic polymer is proposed. By modifying the ratio of the building blocks, the composite material can be fabricated to match the mechanical property of different types of tissues and be further tuned to carry desirable physical and biological function. The results should provide composite engineered materials comparable to native tissue in order to repair and regenerate a variety of wounds and tissues.


Asunto(s)
Materiales Biocompatibles , Andamios del Tejido , Regeneración , Ingeniería de Tejidos , Cicatrización de Heridas
7.
Am J Physiol Lung Cell Mol Physiol ; 319(1): L185-L195, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32432920

RESUMEN

S100A4 is a low-molecular-mass (12 kDa) EF-hand Ca2+-binding S100 protein that is expressed in a broad range of normal tissue and cell types. S100A4 can be secreted from some cells to act in an autocrine or paracrine fashion on target cells and tissues. S100A4 has been reported in the extracellular fluids of subjects with several inflammatory diseases, including asthma. Airway smooth muscle plays a critical role in airway inflammation by synthesizing and secreting inflammatory cytokines. We hypothesized that S100A4 may play an immunomodulatory role in airway smooth muscle. Trachealis smooth muscle tissues were stimulated with recombinant His-S100A4, and the effects on inflammatory responses were evaluated. S100A4 induced the activation of Akt and NF-κB and stimulated eotaxin secretion. It also increased the expression of RAGE and endogenous S100A4 in airway tissues. Stimulation of airway smooth muscle tissues with IL-13 or TNF-α induced the secretion of S100A4 from the tissues and promoted the expression of endogenous receptors for advanced glycation end products (RAGE) and S100A4. The role of RAGE in mediating the responses to S100A4A was evaluated by expressing a mutant nonfunctional RAGE (RAGEΔcyto) in tracheal muscle tissues and by treating tissues with a RAGE inhibitor. S100A4 did not activate NF-κB or Akt in tissues that were expressing RAGEΔcyto or treated with a RAGE inhibitor, indicating that S100A4 mediates its effects by acting on RAGE. Our results demonstrate that inflammatory mediators stimulate the synthesis and secretion of S100A4 in airway smooth muscle tissues and that extracellular S100A4 acts via RAGE to mediate airway smooth muscle inflammation.


Asunto(s)
Inflamación/metabolismo , Inflamación/patología , Pulmón/metabolismo , Músculo Liso/metabolismo , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Proteína de Unión al Calcio S100A4/metabolismo , Transducción de Señal , Animales , Quimiocinas/metabolismo , Perros , Interleucina-13/metabolismo , Modelos Biológicos , Factor de Necrosis Tumoral alfa/metabolismo
8.
Fish Shellfish Immunol ; 99: 462-472, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32070786

RESUMEN

Large yellow croaker (Larimichthys crocea) is one of the most important mariculture fish in China. In the past decades, cryptocaryonosis caused by Cryptocryon irritans has led to huge economic losses, posing great threat to the healthy and sustainable development of L. crocea mariculture industry. As the largest immunologically active mucosal organ in fish, skin provides the first defense line against external pathogens. To better understand the gene expression dynamics, the large yellow croakers were artificially infected with C. irritans and their skin tissues were collected at 0 h, 24 h, 48 h, 72 h and 96 h post infection. The total RNA in the skin tissues were extracted and the transcriptome were sequenced. After sequencing, a total of 1,131, 311, 140 million high quality RNA-seq reads were collected. A set of 215, 473, 968, 1055 differentially expressed genes were identified at 24 h, 48 h, 72 h and 96 h post infection respectively. Further analysis clustered these DEGs into six profiles and 75 hub genes for six profiles were identified. Among these hub genes, 18 immune related genes including TLR5, TOPK, NFKBIZ, MAPK14A were identified post C. irritans infection. Cytokine-cytokine receptor interaction was the only pathway that significantly enriched at four timepoints post infection. This study provides an in-depth understanding of skin transcriptome variance of large yellow croaker after C. irritans infection, which would be helpful for further understanding of the molecular mechanism of L. crocea in response to C. irritans infection.


Asunto(s)
Infecciones por Cilióforos/veterinaria , Proteínas de Peces/genética , Hymenostomatida/inmunología , Perciformes/parasitología , Piel/parasitología , Transcriptoma , Animales , Infecciones por Cilióforos/inmunología , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/parasitología , Proteínas de Peces/inmunología , Expresión Génica , Perfilación de la Expresión Génica , Enfermedades Parasitarias en Animales/inmunología , Perciformes/inmunología , Análisis de Secuencia de ADN , Piel/inmunología
9.
Pediatr Surg Int ; 36(8): 883-890, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32507977

RESUMEN

BACKGROUND/AIMS: Hirschsprung's disease (HSCR) is the most common digestive disease caused by disorders of neural crest development. Despite the known involvement of miR-140-5p in many human diseases, its biological role in Hirschsprung's disease (HSCR) remains undefined. In this study, we sought to reveal the roles of miR-140-5p in the pathogenesis of HSCR. METHODS: Quantitative real-time PCR and western blotting were used to measure the relative expression levels of miRNAs, mRNAs, and proteins in stenotic and dilated sections of the colon of 32 HSCR patients. Targets and proteins were evaluated by western blotting, and Transwell, CCK-8, and flow cytometry assays were adopted to detect the functional effects of miR-140-5p on SH-SY5Y cells. RESULTS: miR-140-5p was significantly downregulated in HSCR tissue samples with increased expression of EGR2, and knockdown of miR-140-5p inhibited cell migration and proliferation and promoted apoptosis in SH-SY5Y cell lines. EGR2 expression was inversely correlated with that of miR-140-5p in cell lines. CONCLUSIONS: miR-140-5p may influence the pathogenesis of HSCR by targeting EGR2.


Asunto(s)
Regulación hacia Abajo/fisiología , Proteína 2 de la Respuesta de Crecimiento Precoz/metabolismo , Enfermedad de Hirschsprung/patología , MicroARNs/antagonistas & inhibidores , Western Blotting , Movimiento Celular , Proliferación Celular , Células Cultivadas , Regulación hacia Abajo/genética , Proteína 2 de la Respuesta de Crecimiento Precoz/genética , Femenino , Enfermedad de Hirschsprung/genética , Enfermedad de Hirschsprung/metabolismo , Humanos , Masculino , MicroARNs/genética , MicroARNs/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa
10.
Anal Chem ; 91(10): 6487-6497, 2019 05 21.
Artículo en Inglés | MEDLINE | ID: mdl-31037939

RESUMEN

This study reports a novel and convenient bimodal method for label-free and signal-off detection of arsenate in environmental samples. Cobalt oxyhydroxide (CoOOH) nanoflakes with facile preparation and intrinsic peroxidase-like activity as nanozyme can efficiently catalyze the conversion of chromogenic substrate such as 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) with the presence of H2O2 into green-colored oxidation products. CoOOH nanoflakes can specifically bind with arsenate via electrostatic attraction and As-O bond interaction, which gives rise to inhibition of the peroxidase-like activity of CoOOH. Thus, through arsenate specific inhibition of CoOOH nanozyme toward ABTS catalysis, a simple colorimetric method was developed for arsenate detection with a detection limit of 3.72 ppb. Based on the system of CoOOH nanozyme and ABTS substrate, this colorimetric method can be converted into an electrochemical sensor for arsenate assay by the utilization of CoOOH nanoflake-modified electrode. The electrochemical measurement can be realized by chronoamperometry, which showed more sensitive and a lower limit of detection as low as 56.1 ppt. The applicability of this bimodal method was demonstrated by measuring arsenate and total arsenic in different real samples such as natural waters and soil extracted solutions, and the results are of satisfactory accuracy as confirmed by inductively coupled plasma mass spectrometry analysis. The bimodal strategy offers obvious advantages including a label-free step, convenient operation, on-site assay, low cost, and high sensitivity, which is promising for reliable detection of arsenate and total arsenic in environmental samples.


Asunto(s)
Arseniatos/química , Cobalto/química , Colorimetría/métodos , Óxidos/química , China , Técnicas Electroquímicas , Contaminantes Ambientales/química , Contaminación Ambiental , Nanoestructuras , Contaminación del Agua
12.
Am J Physiol Lung Cell Mol Physiol ; 314(4): L626-L634, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29212803

RESUMEN

Neutrophil elastase is secreted by inflammatory cells during airway inflammation and can elicit airway hyperreactivity in vivo. Elastase can degrade multiple components of the extracellular matrix. We hypothesized that elastase might disrupt the connections between airway smooth muscle (ASM) cells and the extracellular matrix and that this might have direct effects on ASM tissue responsiveness and inflammation. The effect of elastase treatment on ASM contractility was assessed in vitro in isolated strips of canine tracheal smooth muscle by stimulation of tissues with cumulatively increasing concentrations of acetylcholine (ACh) and measurement of contractile force. Elastase treatment potentiated contractile responses to ACh at low concentrations but suppressed the maximal contractile force generated by the tissues without affecting the phosphorylation of myosin regulatory light chain (RLC). Elastase also promoted the secretion of eotaxin and the activation of Akt in ASM tissues and decreased expression of smooth muscle myosin heavy chain, consistent with promotion of a synthetic inflammatory phenotype. As the degradation of matrix proteins can alter integrin engagement, we evaluated the effect of elastase on the assembly and activation of integrin-associated adhesion junction complexes in ASM tissues. Elastase led to talin cleavage, reduced talin binding to vinculin, and suppressed activation of the adhesome proteins paxillin, focal adhesion kinase, and vinculin, indicating that elastase causes the disassembly of adhesion junction complexes and the inactivation of adhesome signaling proteins. We conclude that elastase promotes an inflammatory phenotype and increased sensitivity to ACh in ASM tissues by disrupting signaling pathways mediated by integrin-associated adhesion complexes.


Asunto(s)
Contracción Muscular/fisiología , Miocitos del Músculo Liso/inmunología , Elastasa Pancreática/metabolismo , Tráquea/inmunología , Acetilcolina/metabolismo , Animales , Membrana Celular , Células Cultivadas , Perros , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Miocitos del Músculo Liso/enzimología , Miocitos del Músculo Liso/patología , Cadenas Ligeras de Miosina/metabolismo , Fenotipo , Fosforilación , Transducción de Señal , Tráquea/enzimología , Tráquea/patología
13.
Biotechnol Bioeng ; 114(10): 2371-2378, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28542804

RESUMEN

The clinical translation of cell-based therapeutics often requires highly sensitive, non-invasive imaging tools to assess cell function and distribution in vivo. The objective of this research was to determine whether human Sodium-Iodide Symporter (hNIS) ectopic expression in endothelial cells (ECs) in combination with single-photon emission computed tomography (SPECT) is a feasible approach to non-invasively monitor the presence and viability of an engineered endothelium on expanded polytetrafluoroethylene (ePTFE). Human umbilical vein endothelial cells (HUVECs) were transduced with pLL3.7-hNIS via lentivirus with multiplicity of infection (MOI) of 0, 2, 5, and 10 (n = 4). Ectopic expression of hNIS in HUVECs via optimized lentiviral transduction (MOI 5) enabled cell uptake of a radioisotope that can be detected by SPECT without affecting endothelial cell viability, oxidative stress, or antithrombogenic functions. The viability and distribution of an engineered endothelium grown on ePTFE coated with the biodegradable elastomer poly(1, 8 octamethylene citrate) (POC) and exposed to fluid flow was successfully monitored non-invasively by SPECT. We report the feasibility of a non-invasive, highly sensitive and functional assessment of an engineered endothelium on ePTFE using a combination of SPECT and X-ray computed tomography (SPECT/CT) imaging and hNIS ectopic expression in ECs. This technology potentially allows for the non-invasive assessment of transplanted living cells in vascular conduits. Biotechnol. Bioeng. 2017;114: 2371-2377. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Células Endoteliales/citología , Células Endoteliales/fisiología , Endotelio Vascular/diagnóstico por imagen , Endotelio Vascular/metabolismo , Simportadores/metabolismo , Ingeniería de Tejidos/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Células Cultivadas , Humanos , Simportadores/genética
14.
Nano Lett ; 16(11): 6916-6923, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27748606

RESUMEN

The extremely low efficient cytosolic release of the internalized siRNA has emerged recently as a central issue for siRNA delivery, while there is a lack of guidelines to facilitate the cytosolic release of internalized siRNA. To address these concerns, we studied the contribution of the pH-sensitive inner core on handling the cytosolic release of siRNA delivered by a series of PG-P(DPAx-co-DMAEMAy)-PCB amphiphilic polycation nanomicelles (GDDC-Ms) with extremely low internalization (<1/4 of lipofactamine 2000 (Lipo2000)). Significantly, just by varying the mole ratio of DPA and DMAEMA to adjust the initial disassembly pH (pHdis) of the core near to 6.8, GDDC4-Ms/siRNA could get nearly 98.8% silencing efficiency at w/w = 12 with 50 nM siRNA and ∼78% silencing efficiency at w/w = 30 with a very low dose of 5 nM siRNA in HepG-2 cell lines, while Lipo2000 only got 65.7% with 50 nM siRNA. Furthermore, ∼98.4% silencing efficiency was also realized in the hard-to-transfect human acute monoblastic leukemia cell line U937 by GDDC4-Ms/siRNA (at w/w = 15, 50 nM siRNA), in the inefficient case for Lipo2000. Additionally, the high silencing efficiency (∼80%) in skin tissue in vivo was discovered. Undoubtedly, the robust potential of GDDC4-Ms in handling the cytosolic release paves a simple but efficient new way for the design of the nonviral siRNA vector.

15.
J Biol Chem ; 290(18): 11403-16, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25759389

RESUMEN

Vasodilator-stimulated phosphoprotein (VASP) can catalyze actin polymerization by elongating actin filaments. The elongation mechanism involves VASP oligomerization and its binding to profilin, a G-actin chaperone. Actin polymerization is required for tension generation during the contraction of airway smooth muscle (ASM); however, the role of VASP in regulating actin dynamics in ASM is not known. We stimulated ASM cells and tissues with the contractile agonist acetylcholine (ACh) or the adenylyl cyclase activator, forskolin (FSK), a dilatory agent. ACh and FSK stimulated VASP Ser(157) phosphorylation by different kinases. Inhibition of VASP Ser(157) phosphorylation by expression of the mutant VASP S157A in ASM tissues suppressed VASP phosphorylation and membrane localization in response to ACh, and also inhibited contraction and actin polymerization. ACh but not FSK triggered the formation of VASP-VASP complexes as well as VASP-vinculin and VASP-profilin complexes at membrane sites. VASP-VASP complex formation and the interaction of VASP with vinculin and profilin were inhibited by expression of the inactive vinculin mutant, vinculin Y1065F, but VASP phosphorylation and membrane localization were unaffected. We conclude that VASP phosphorylation at Ser(157) mediates its localization at the membrane, but that VASP Ser(157) phosphorylation and membrane localization are not sufficient to activate its actin catalytic activity. The interaction of VASP with activated vinculin at membrane adhesion sites is a necessary prerequisite for VASP-mediated molecular processes necessary for actin polymerization. Our results show that VASP is a critical regulator of actin dynamics and tension generation during the contractile activation of ASM.


Asunto(s)
Actinas/química , Moléculas de Adhesión Celular/metabolismo , Proteínas de Microfilamentos/metabolismo , Contracción Muscular , Músculo Liso/fisiología , Fosfoproteínas/metabolismo , Multimerización de Proteína , Tráquea/fisiología , Vinculina/metabolismo , Acetilcolina/farmacología , Animales , Biocatálisis , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Pollos , Colforsina/farmacología , Perros , Epinefrina/farmacología , Humanos , Contracción Muscular/efectos de los fármacos , Músculo Liso/citología , Fosforilación/efectos de los fármacos , Profilinas/metabolismo , Estructura Cuaternaria de Proteína , Transporte de Proteínas/efectos de los fármacos , Tirosina/metabolismo , Vinculina/química
16.
Am J Physiol Lung Cell Mol Physiol ; 311(5): L893-L902, 2016 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-27612967

RESUMEN

The effects of mechanical forces and focal adhesion kinase (FAK) in regulating the inflammatory responses of airway smooth muscle (ASM) tissues to stimulation with interleukin (IL)-13 were investigated. Canine tracheal tissues were subjected to different mechanical loads in vitro, and the effects of mechanical load on eotaxin secretion and inflammatory signaling pathways in response to IL-13 were determined. Eotaxin secretion by tissues in response to IL-13 was significantly inhibited in muscles maintained at a higher (+) load compared with those at a lower (-) load as assessed by ELISA, and Akt activation was also reduced in the higher (+) loaded tissues. Conversely the (+) mechanical load increased activation of the focal adhesion proteins FAK and paxillin in the tissues. The role of FAK in regulating the mechanosensitive responses was assessed by overexpressing FAK-related nonkinase in the tissues, by expressing the FAK kinase-dead mutant FAK Y397F, or by treating tissues with the FAK inhibitor PF-573228. FAK inactivation potentiated Akt activity and increased eotaxin secretion in response to IL-13. FAK inhibition also suppressed the mechanosensitivity of Akt activation and eotaxin secretion. In addition, FAK inactivation suppressed smooth muscle myosin heavy chain expression induced by the higher (+) mechanical load. The results demonstrate that the imposition of a higher mechanical load on airway smooth muscle stimulates FAK activation, which promotes the expression of the differentiated contractile phenotype and suppresses the synthetic phenotype and the inflammatory responses of the muscle tissue.


Asunto(s)
Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Músculo Liso/enzimología , Estrés Mecánico , Animales , Quimiocina CCL11/metabolismo , Perros , Activación Enzimática/efectos de los fármacos , Proteína-Tirosina Quinasas de Adhesión Focal/antagonistas & inhibidores , Proteínas Fluorescentes Verdes/metabolismo , Inflamación/metabolismo , Inflamación/patología , Interleucina-13/metabolismo , Ratones , Modelos Biológicos , Músculo Liso/efectos de los fármacos , Músculo Liso/patología , Cadenas Pesadas de Miosina/metabolismo , Paxillin/metabolismo , Fenotipo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Quinolonas/farmacología , Sulfonas/farmacología , Tráquea/patología
17.
Breast Cancer Res Treat ; 154(2): 423-34, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26476723

RESUMEN

Novel, non-invasive biomarkers to diagnose breast cancer with high sensitivity and specificity are greatly desired. Circulating microRNAs (miRNAs) show potential for breast cancer detection, but the existing results appear to be mixed. Using microscale serum, we established a novel serum-direct multiplex detection assay based on RT-PCR (SdM-RT-PCR). Ninety-three miRNAs dysregulated or with functions in breast cancer were selected as candidates, and additional 3 miRNAs were chosen as endogenous controls. We first conducted miRNA profiling of these 96 miRNAs by SdM-RT-PCR using the sera of 25 breast cancer patients at diagnosis prior to treatment and 20 age-matched healthy controls. miRNAs showing significantly different expression levels between patients and controls were further analyzed using a logistic regression model. A miRNA signature was validated in an independent set of 128 serum samples composed of 76 breast cancer patients and 52 healthy controls. In the discovery stage, we identified 23 miRNAs as significantly dysregulated in breast cancer patients compared with healthy controls. Of these, 10 miRNAs were previously identified as dysregulated in breast cancer; 14 miRNAs remained significant after P-values were adjusted by both correction methods. Principal component analysis and hierarchical clustering of these miRNAs separated patients from controls. Furthermore, the 3-miRNA signature (miR-199a, miR-29c, and miR-424) with the highest diagnostic accuracy for distinguishing breast cancer patients from controls by ROC curve analysis (AUC = 0.888) was successfully confirmed in the validation set (AUC = 0.901). Our data demonstrate that the SdM-RT-PCR assay is an effective breast cancer profiling method that utilizes very small volumes and is compatible with Biobank. Furthermore, the identified 3-miRNA signature is a promising circulating biomarker for breast cancer diagnosis.


Asunto(s)
Biomarcadores de Tumor , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/genética , MicroARNs/genética , Adulto , Anciano , Neoplasias de la Mama/sangre , Estudios de Casos y Controles , Análisis por Conglomerados , Detección Precoz del Cáncer , Femenino , Perfilación de la Expresión Génica , Humanos , MicroARNs/sangre , Persona de Mediana Edad , Estadificación de Neoplasias , Curva ROC , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados
18.
Can J Physiol Pharmacol ; 93(2): 129-36, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25531582

RESUMEN

Recent studies have demonstrated a novel molecular mechanism for the regulation of airway smooth muscle (ASM) contraction by RhoA GTPase. In ASM tissues, both myosin light chain (MLC) phosphorylation and actin polymerization are required for active tension generation. RhoA inactivation dramatically suppresses agonist-induced tension development and completely inhibits agonist-induced actin polymerization, but only slightly reduces MLC phosphorylation. The inhibition of MLC phosphatase does not reverse the effects of RhoA inactivation on contraction or actin polymerization. Thus, RhoA regulates ASM contraction through its effects on actin polymerization rather than MLC phosphorylation. Contractile stimulation of ASM induces the recruitment and assembly of paxillin, vinculin, and focal adhesion kinase (FAK) into membrane adhesion complexes (adhesomes) that regulate actin polymerization by catalyzing the activation of cdc42 GTPase by the G-protein-coupled receptor kinase-interacting target (GIT) - p21-activated kinase (PAK) - PAK-interacting exchange factor (PIX) complex. Cdc42 is a necessary and specific activator of the actin filament nucleation activator, N-WASp. The recruitment and activation of paxillin, vinculin, and FAK is prevented by RhoA inactivation, thus preventing cdc42 and N-WASp activation. We conclude that RhoA regulates ASM contraction by catalyzing the assembly and activation of membrane adhesome signaling modules that regulate actin polymerization, and that the RhoA-mediated assembly of adhesome complexes is a fundamental step in the signal transduction process in response to a contractile agonist.


Asunto(s)
GTP Fosfohidrolasas/metabolismo , Pulmón/metabolismo , Contracción Muscular , Músculo Liso/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Actinas/metabolismo , Humanos , Transducción de Señal
19.
Bioconjug Chem ; 25(11): 2055-66, 2014 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-25260060

RESUMEN

The therapeutic application of small interfering RNA (siRNA) requires safe nanocarriers for specific and efficient delivery in vivo. Herein, PEGylated cationic cerasomes (PCCs) were fabricated by doping a cationic lipid with a hydroxyl group into nanohybrid cerasomes. Multiple properties of PCCs provide a solution to many of the limitations associated with current platforms for the delivery of siRNA. The polyorganosiloxane surface imparts PCCs with higher morphological stability than conventional liposomes. The PEGylation of the cationic cerasome could protect the cerasome nanoparticles from agglomeration and macrophage capture, reduce protein absorption, and consequently prolong the blood circulating time and enhance the siRNA delivery efficiency. In addition, incorporation of the lipid containing a hydroxyl group further facilitates endosome release. Moreover, PCCs were further used to transport siRNA into the cytosol primarily via endocytosis. When applied to systemic administration, PCCs have demonstrated effective delivery into the liver and preferential uptake by hepatocytes in mice, thereby leading to high siRNA gene-silencing activity. All these results show potential therapeutic applications of PCCs-mediated delivery of siRNA for liver diseases.


Asunto(s)
Portadores de Fármacos/química , Nanopartículas/química , Fosfatidiletanolaminas/química , Polietilenglicoles/química , ARN Interferente Pequeño/química , ARN Interferente Pequeño/genética , Transfección , Animales , Transporte Biológico , Portadores de Fármacos/metabolismo , Silenciador del Gen , Células HeLa , Células Hep G2 , Humanos , Hidroxilación , Liposomas , Hígado/metabolismo , Ratones , Modelos Moleculares , Conformación de Ácido Nucleico , ARN Interferente Pequeño/metabolismo
20.
Foods ; 13(7)2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38611298

RESUMEN

In this study, we investigated the body characteristics, carotenoid composition, and nutritional quality of Eriocheir sinensis with different hepatopancreas redness (a*). We distributed the crabs into two groups based on the hepatopancreas a* values and compared their body characteristics, chroma, carotenoid composition, and protein, lipid, total sugar, amino acid, and fatty acid content via paired t-test. The results revealed that the relationships between hepatopancreas a* values and crab quality are sex specific. In female crabs, the differences in nutritional characteristics were evident mainly in the hepatopancreases and ovaries. In the redder hepatopancreases, the content of zeaxanthin and ß-carotene increased, and the levels of C22:6n3 and C20:5n3 decreased (p < 0.05). In the ovaries, the content of astaxanthin, canthaxanthin, ß-carotene, umami, and sweet amino acids were lower in the redder hepatopancreas crabs (p < 0.05). In male crabs, there were positive relationships between hepatopancreas a* and amino acid and fatty acid content. The content of leucine, arginine, and total umami amino acids in muscles and of unsaturated fatty acids and n-6 polyunsaturated fatty acids in hepatopancreases and testicles increased with increasing hepatopancreas a* values (p < 0.05). Therefore, the redder the hepatopancreas, the higher the nutritional quality of male crabs.

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