Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 144
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Hepatol ; 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38670321

RESUMEN

BACKGROUND & AIMS: The precise pathomechanisms underlying the development of non-alcoholic steatohepatitis (NASH, also known as metabolic dysfunction-associated steatohepatitis [MASH]) remain incompletely understood. In this study, we investigated the potential role of EF-hand domain family member D2 (EFHD2), a novel molecule specific to immune cells, in the pathogenesis of NASH. METHODS: Hepatic EFHD2 expression was characterized in patients with NASH and two diet-induced NASH mouse models. Single-cell RNA sequencing (scRNA-seq) and double-immunohistochemistry were employed to explore EFHD2 expression patterns in NASH livers. The effects of global and myeloid-specific EFHD2 deletion on NASH and NASH-related hepatocellular carcinoma were assessed. Molecular mechanisms underlying EFHD2 function were investigated, while chemical and genetic investigations were performed to assess its potential as a therapeutic target. RESULTS: EFHD2 expression was significantly elevated in hepatic macrophages/monocytes in both patients with NASH and mice. Deletion of EFHD2, either globally or specifically in myeloid cells, improved hepatic steatosis, reduced immune cell infiltration, inhibited lipid peroxidation-induced ferroptosis, and attenuated fibrosis in NASH. Additionally, it hindered the development of NASH-related hepatocellular carcinoma. Specifically, deletion of myeloid EFHD2 prevented the replacement of TIM4+ resident Kupffer cells by infiltrated monocytes and reversed the decreases in patrolling monocytes and CD4+/CD8+ T cell ratio in NASH. Mechanistically, our investigation revealed that EFHD2 in myeloid cells interacts with cytosolic YWHAZ (14-3-3ζ), facilitating the translocation of IFNγR2 (interferon-γ receptor-2) onto the plasma membrane. This interaction mediates interferon-γ signaling, which triggers immune and inflammatory responses in macrophages during NASH. Finally, a novel stapled α-helical peptide targeting EFHD2 was shown to be effective in protecting against NASH pathology in mice. CONCLUSION: Our study reveals a pivotal immunomodulatory and inflammatory role of EFHD2 in NASH, underscoring EFHD2 as a promising druggable target for NASH treatment. IMPACT AND IMPLICATIONS: Non-alcoholic steatohepatitis (NASH) represents an advanced stage of non-alcoholic fatty liver disease (NAFLD); however, not all patients with NAFLD progress to NASH. A key challenge is identifying the factors that trigger inflammation, which propels the transition from simple fatty liver to NASH. Our research pinpointed EFHD2 as a pivotal driver of NASH, orchestrating the over-activation of interferon-γ signaling within the liver during NASH progression. A stapled peptide designed to target EFHD2 exhibited therapeutic promise in NASH mice. These findings support the potential of EFHD2 as a therapeutic target in NASH.

2.
BMC Cancer ; 24(1): 576, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730348

RESUMEN

OBJECTIVE: Nasopharyngeal adenoid cystic carcinoma (NACC) is a rare malignancy with special biological features. Controversies exist regarding the treatment approach and prognostic factors in the IMRT era. This study aimed to evaluate the long-term outcomes and management approaches in NACC. METHODS: Fifty patients with NACC at our institution between 2010 and 2020 were reviewed. Sixteen patients received primary radiotherapy (RT), and 34 patients underwent primary surgery. RESULTS: Between January 2010 and October 2020, a total of 50 patients with pathologically proven NACC were included in our analysis. The median follow-up time was 58.5 months (range: 6.0-151.0 months). The 5-year overall survival rate (OS) and progression-free survival rate (PFS) were 83.9% and 67.5%, respectively. The 5-year OS rates of patients whose primary treatment was surgery and RT were 90.0% and 67.3%, respectively (log-rank P = 0.028). The 5-year PFS rates of patients whose primary treatment was surgery or RT were 80.8% and 40.7%, respectively (log-rank P = 0.024). Multivariate analyses showed that nerve invasion and the pattern of primary treatment were independent factors associated with PFS. CONCLUSIONS: Due to the relative insensitivity to radiation, primary surgery seemed to provide a better chance of disease control and improved survival in NACC. Meanwhile, postoperative radiotherapy should be performed for advanced stage or residual tumours. Cranial nerve invasion and treatment pattern might be important factors affecting the prognosis of patients with NACC.


Asunto(s)
Carcinoma Adenoide Quístico , Neoplasias Nasofaríngeas , Radioterapia de Intensidad Modulada , Humanos , Carcinoma Adenoide Quístico/radioterapia , Carcinoma Adenoide Quístico/mortalidad , Carcinoma Adenoide Quístico/patología , Carcinoma Adenoide Quístico/cirugía , Masculino , Femenino , Radioterapia de Intensidad Modulada/métodos , Persona de Mediana Edad , Adulto , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/mortalidad , Neoplasias Nasofaríngeas/patología , Anciano , Estudios Retrospectivos , Carcinoma Nasofaríngeo/radioterapia , Carcinoma Nasofaríngeo/mortalidad , Carcinoma Nasofaríngeo/patología , Adulto Joven , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento , Estudios de Seguimiento , Adolescente , Supervivencia sin Progresión
3.
Int J Mol Sci ; 25(10)2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38791596

RESUMEN

Ovarian follicular fluid (FF) has a direct impact on oocyte quality, playing key roles in fertilization, implantation, and early embryo development. In our recent study, we found FF thromboxane (TX) to be a novel factor inversely correlated with oocyte maturation and identified thrombin, transforming growth factor ß (TGFß), TNF-α, and follicular granulosa cells (GCs) as possible contributors to FF TX production. Therefore, this study sought to investigate the role of TGFß3 in regulating TX generation in human ovarian follicular GCs. TGFß3 was differentially and significantly present in the FF of large and small follicles obtained from IVF patients with average concentrations of 68.58 ± 12.38 and 112.55 ± 14.82 pg/mL, respectively, and its levels were correlated with oocyte maturity. In an in vitro study, TGFß3 induced TX generation/secretion and the converting enzyme-COX-2 protein/mRNA expression both in human HO23 and primary cultured ovarian follicular GCs. While TGFßRI and Smad2/3 signaling was mainly required for COX-2 induction, ERK1/2 appeared to regulate TX secretion. The participation of Smad2/3 and COX-2 in TGFß3-induced TX generation/secretion could be further supported by the observations that Smad2/3 phosphorylation and nuclear translocation and siRNA knockdown of COX-2 expression compromised TX secretion in GCs challenged with TGFß3. Taken together, the results presented here first demonstrated that FF TGFß3 levels differ significantly in IVF patients' large preovulatory and small mid-antral follicles and are positively associated with oocyte maturation. TGFß3 can provoke TX generation by induction of COX-2 mRNA/protein via a TGFßR-related canonical Smad2/3 signaling pathway, and TX secretion possibly by ERK1/2. These imply that TGFß3 is one of the inducers for yielding FF TX in vivo, which may play a role in folliculogenesis and oocyte maturation.


Asunto(s)
Ciclooxigenasa 2 , Líquido Folicular , Células de la Granulosa , Transducción de Señal , Proteína Smad2 , Proteína smad3 , Factor de Crecimiento Transformador beta3 , Humanos , Femenino , Ciclooxigenasa 2/metabolismo , Ciclooxigenasa 2/genética , Células de la Granulosa/metabolismo , Proteína Smad2/metabolismo , Proteína Smad2/genética , Proteína smad3/metabolismo , Proteína smad3/genética , Líquido Folicular/metabolismo , Factor de Crecimiento Transformador beta3/metabolismo , Factor de Crecimiento Transformador beta3/genética , Adulto , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Receptor Tipo I de Factor de Crecimiento Transformador beta/genética , Folículo Ovárico/metabolismo , Oocitos/metabolismo , Células Cultivadas
4.
J Appl Microbiol ; 134(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36597783

RESUMEN

Acinetobacter baumannii is a strictly aerobic, nonmotile, nonfermenting, gram-negative bacillus. It is a highly infectious and invasive pathogen with high mortality and morbidity rates among immunodeficient patients. Due to increasing levels of drug resistance and the inefficiency of existing antimicrobial treatments, it is crucial to develop novel agents to control this pathogen. Several recent studies have investigated virulence factors that are associated with the pathogenesis of A. baumannii, and could thus serve as novel therapeutic targets. The present review comprehensively summarizes the current understanding of these virulence factors and their mechanisms in A. baumannii. We also highlight factors that could be potential therapeutic targets, as well as list candidate virulence factors for future researchers and clinical practitioners.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Antiinfecciosos , Humanos , Factores de Virulencia/genética , Virulencia , Infecciones por Acinetobacter/tratamiento farmacológico , Antiinfecciosos/uso terapéutico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Farmacorresistencia Bacteriana Múltiple
5.
Eur Heart J ; 43(43): 4579-4595, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-35929617

RESUMEN

AIMS: Exercise confers protection against cardiovascular ageing, but the mechanisms remain largely unknown. This study sought to investigate the role of fibronectin type-III domain-containing protein 5 (FNDC5)/irisin, an exercise-associated hormone, in vascular ageing. Moreover, the existence of FNDC5/irisin in circulating extracellular vesicles (EVs) and their biological functions was explored. METHODS AND RESULTS: FNDC5/irisin was reduced in natural ageing, senescence, and angiotensin II (Ang II)-treated conditions. The deletion of FNDC5 shortened lifespan in mice. Additionally, FNDC5 deficiency aggravated vascular stiffness, senescence, oxidative stress, inflammation, and endothelial dysfunction in 24-month-old naturally aged and Ang II-treated mice. Conversely, treatment of recombinant irisin alleviated Ang II-induced vascular stiffness and senescence in mice and vascular smooth muscle cells. FNDC5 was triggered by exercise, while FNDC5 knockout abrogated exercise-induced protection against Ang II-induced vascular stiffness and senescence. Intriguingly, FNDC5 was detected in human and mouse blood-derived EVs, and exercise-induced FNDC5/irisin-enriched EVs showed potent anti-stiffness and anti-senescence effects in vivo and in vitro. Adeno-associated virus-mediated rescue of FNDC5 specifically in muscle but not liver in FNDC5 knockout mice, promoted the release of FNDC5/irisin-enriched EVs into circulation in response to exercise, which ameliorated vascular stiffness, senescence, and inflammation. Mechanistically, irisin activated DnaJb3/Hsp40 chaperone system to stabilize SIRT6 protein in an Hsp70-dependent manner. Finally, plasma irisin concentrations were positively associated with exercise time but negatively associated with arterial stiffness in a proof-of-concept human study. CONCLUSION: FNDC5/irisin-enriched EVs contribute to exercise-induced protection against vascular ageing. These findings indicate that the exerkine FNDC5/irisin may be a potential target for ageing-related vascular comorbidities.


Asunto(s)
Vesículas Extracelulares , Sirtuinas , Humanos , Ratones , Animales , Anciano , Preescolar , Fibronectinas/metabolismo , Factores de Transcripción/metabolismo , Ratones Noqueados , Envejecimiento , Angiotensina II/farmacología , Inflamación/metabolismo , Músculo Esquelético/metabolismo , Proteínas del Choque Térmico HSP40/metabolismo
6.
Int J Mol Sci ; 24(20)2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37894811

RESUMEN

In this study, we confirmed that thrombin significantly increases the production of COX-2 and PGE2 in human tracheal smooth muscle cells (HTSMCs), leading to inflammation in the airways and lungs. These molecules are well-known contributors to various inflammatory diseases. Here, we investigated in detail the involved signaling pathways using specific inhibitors and small interfering RNAs (siRNAs). Our results demonstrated that inhibitors targeting proteins such as protein kinase C (PKC)δ, proline-rich tyrosine kinase 2 (Pyk2), c-Src, epidermal growth factor receptor (EGFR), phosphatidylinositol 3-kinase (PI3K), or activator protein-1 (AP-1) effectively reduced thrombin-induced COX-2 and PGE2 production. Additionally, transfection with siRNAs against PKCδ, Pyk2, c-Src, EGFR, protein kinase B (Akt), or c-Jun mitigated these responses. Furthermore, our observations revealed that thrombin stimulated the phosphorylation of key components of the signaling cascade, including PKCδ, Pyk2, c-Src, EGFR, Akt, and c-Jun. Thrombin activated COX-2 promoter activity through AP-1 activation, a process that was disrupted by a point-mutated AP-1 site within the COX-2 promoter. Finally, resveratrol (one of the most researched natural polyphenols) was found to effectively inhibit thrombin-induced COX-2 expression and PGE2 release in HTSMCs through blocking the activation of Pyk2, c-Src, EGFR, Akt, and c-Jun. In summary, our findings demonstrate that thrombin-induced COX-2 and PGE2 generation involves a PKCδ/Pyk2/c-Src/EGFR/PI3K/Akt-dependent AP-1 activation pathway. This study also suggests the potential use of resveratrol as an intervention for managing airway inflammation.


Asunto(s)
Proteínas Proto-Oncogénicas c-akt , Factor de Transcripción AP-1 , Humanos , Proteína Tirosina Quinasa CSK/metabolismo , Ciclooxigenasa 2/metabolismo , Dinoprostona/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Quinasa 2 de Adhesión Focal/genética , Quinasa 2 de Adhesión Focal/metabolismo , Inflamación/metabolismo , Miocitos del Músculo Liso/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Resveratrol/farmacología , Resveratrol/metabolismo , Familia-src Quinasas/metabolismo , Trombina/metabolismo , Factor de Transcripción AP-1/metabolismo
7.
J Cell Physiol ; 237(3): 1871-1887, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34897684

RESUMEN

A higher expression level of mitogenic fibroblast growth factor-2 (FGF-2) has been reported in human nasal mucus of both chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). Meanwhile, we have shown that long pentraxin 3 (PTX3), an essential component of humoral innate immunity that is produced at sites of infection and inflammation, was overproduced in human nasal mucosae and secretions of CRSsNP. Therefore, this study was aimed to investigate how FGF-2 regulates PTX3 expression in human CRSsNP nasal mucosa-derived fibroblast cells (hNMDFs). The FGF-2 treatment caused ptx3 mRNA expression and PTX3 protein induction and secretion. In parallel, a differential expression of FGF receptor (FGFR)-1 to FGFR-4 was observed in hNMDFs and human nasal tissues. While conventionally known PI3K/Akt/mTOR and AP-1 pathways following FGFR activation were shown to be involved, the protein kinase Cδ (PKCδ) and cAMP response element-binding protein (CREB) were also found to be as critical signaling molecules in FGF-2-induced PTX3 induction. The PKCδ and CREB activation could be detected in total cells and in the cell nucleus. Accordingly, a novel CREB binding sequence was detected in the human ptx3 promoter region and could interact with activated CREB in cells challenged with FGF-2. Surprisingly, the phospholipase D (PLD), but not phosphoinositide- and phosphatidylcholine-phospholipase C, was necessarily required for PKCδ and CREB activation. Therefore, we demonstrated here for the first time that FGF-2 mediates PTX3 production not only through PI-3K/Akt/mTOR and AP-1 activation, but also through a novel FGFR-PLD-PKCδ-CREB cellular signaling pathway.


Asunto(s)
Pólipos Nasales , Fosfolipasa D , Sinusitis , Humanos , Proteína C-Reactiva , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Factor 2 de Crecimiento de Fibroblastos/genética , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Fibroblastos/metabolismo , Pólipos Nasales/genética , Pólipos Nasales/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfolipasa D/genética , Fosfolipasa D/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Componente Amiloide P Sérico , Sinusitis/genética , Sinusitis/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Factor de Transcripción AP-1/genética , Factor de Transcripción AP-1/metabolismo
8.
Am J Physiol Renal Physiol ; 320(5): F799-F813, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33749324

RESUMEN

Glutamate N-methyl-d-aspartate receptor (NMDAR) hyperfunction is known to contribute to acute renal failure due to ischemia-reperfusion and endotoxemia. d-Serine is a coagonist for NMDAR activation, but whether NMDARs play a role in d-serine-mediated nephrotoxicity remains unclear. Here, we demonstrate that NMDAR blockade ameliorated d-serine-induced renal injury. In NMDAR-expressing LLC-PK1 cells, which were used as a proximal tubule model, d-serine but not l-serine induced cytotoxicity in a dose-dependent manner, which was abrogated by the selective NMDAR blockers MK-801 and AP-5. Time-dependent oxidative stress, evidenced by gradually increased superoxide and H2O2 production, was associated with d-serine-mediated cytotoxicity; these reactive oxygen species could be alleviated not only after NMDAR inhibition but also by NADPH oxidase (NOX) inhibition. Activation of protein kinase C (PKC)-δ and PKC-ζ is a downstream signal for NMDAR-mediated NOX activation because PKC inhibition diminishes the NOX activity that is induced by d-serine. Renal injury was further confirmed in male Wistar rats that intraperitoneally received d-serine but not l-serine. Peak changes in glucosuria, proteinuria, and urinary excretion of lactate dehydrogenase and malondialdehyde were found after 24 h of treatment. Persistent tubular damage was observed after 7 days of treatment. Cotreatment with the NMDAR blocker MK-801 for 24 h abolished d-serine-induced functional insufficiency and tubular damage. MK-801 attenuated renal superoxide formation by lowering NOX activity and protein upregulation of NOX4 but not NOX2. These results reveal that NMDAR hyperfunction underlies d-serine-induced renal injury via the effects of NOX4 on triggering oxidative stress.NEW & NOTEWORTHY Ionotropic N-methyl-d-aspartate receptors (NMDARs) are not only present in the nervous system but also expressed in the kidney. Overstimulation of renal NMDARs leads to oxidative stress via the signal pathway of calcium/protein kinase C/NADPH oxidase in d-serine-mediated tubular cell damage. Intervention of NMDAR blockade may prevent acute renal injury caused by d-serine.


Asunto(s)
Túbulos Renales Proximales/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Insuficiencia Renal/metabolismo , Serina , Animales , Calcio/metabolismo , Modelos Animales de Enfermedad , Antagonistas de Aminoácidos Excitadores/farmacología , Túbulos Renales Proximales/efectos de los fármacos , Túbulos Renales Proximales/patología , Células LLC-PK1 , Masculino , NADPH Oxidasa 4/metabolismo , Estrés Oxidativo , Proteína Quinasa C/metabolismo , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Insuficiencia Renal/inducido químicamente , Insuficiencia Renal/patología , Insuficiencia Renal/prevención & control , Transducción de Señal , Porcinos
9.
Clin Lab ; 67(9)2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34542977

RESUMEN

BACKGROUND: With the development of science and technology, self-service facilities have been widely used in hospitals. This study aimed to assess the microbial contamination characteristics on touch surfaces in outpatient, self-service facilities from Monday to Friday. METHODS: Touch surfaces in outpatient facilities were swabbed and surveyed for total microbial growth before and after work every morning. Selected bacteria were identified to screen for pathogenic organisms. RESULTS: There were 360 samples collected, 87 samples (24.2%) were culture-positive. Staphylococcus species were the main microbial contamination. The three most common bacteria were S. hominis, S. epidermidis and S. hemolyticus. After work, more microbial contamination was found on Monday (p = 0.029). There was no difference in sample positive rates between self-service facilities and manual service area. Although, the antibiotic resistance patterns of different staphylococcus species were different, the overall drug resistance rate is low. Only one S. aureus was methicillin-Sensitive S. aureus. CONCLUSIONS: The self-service facilities' touch surfaces microbial contamination were similar to manual service area, but the more used, the more microbial contamination was found. Hospitals should enhance cleaning times of self-service facilities to keep them clean, especially on Mondays.


Asunto(s)
Staphylococcus aureus , Tacto , Humanos , Meticilina , Pacientes Ambulatorios , Staphylococcus
10.
Clin Sci (Lond) ; 134(19): 2565-2580, 2020 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-33006369

RESUMEN

Short bowel (SB) increases the risk of kidney stones. However, the underlying mechanism is unclear. Here, we examined how SB affected renal oxalate and citrate handlings for in vivo hyperoxaluric rats and in vitro tubular cells. SB was induced by small intestine resection in male Wistar rats. Sham-operated controls had no resection. After 7 days of recovery, the rats were divided into control, SB (both fed with distilled water), ethylene glycol (EG), and SB+EG (both fed with 0.75% EG for hyperoxaluric induction) groups for 28 days. We collected the plasma, 24 h of urine, kidney, and intestine tissues for analysis. Hypocitraturia was found and persisted up to 28 days for the SB group. Hypocalcemia and high plasma parathyroid hormone (PTH) levels were found in the 28-day SB rats. SB aggravated EG-mediated oxalate nephropathy by fostering hyperoxaluria and hypocitraturia, and increasing the degree of supersaturation and calcium oxalate (CaOx) crystal deposition. These effects were associated with renal up-regulations of the oxalate transporter solute carrier family 26 (Slc26)a6 and citrate transporter sodium-dependent dicarboxylate cotransporter-1 (NaDC-1) but not Slc26a2. The effects of PTH on the SB kidneys were then examined in NRK-52E tubular cells. Recombinant PTH attenuated oxalate-mediated cell injury and up-regulated NaDC-1 via protein kinase A (PKA) activation. PTH, however, showed no additive effects on oxalate-induced Slc26a6 and NaDC-1 up-regulation. Together, these results demonstrated that renal NaDC-1 upregulation-induced hypocitraturia weakened the defense against Slc26a6-mediated hyperoxaluria in SB kidneys for excess CaOx crystal formation. Increased tubular NaDC-1 expression caused by SB relied on PTH.


Asunto(s)
Oxalato de Calcio/metabolismo , Proteínas Portadoras/metabolismo , Hiperoxaluria/metabolismo , Intestino Delgado/cirugía , Oxalatos/metabolismo , Animales , Calcio/sangre , Oxalato de Calcio/sangre , Cristalización , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Transportadores de Ácidos Dicarboxílicos/metabolismo , Hiperoxaluria/orina , Riñón/metabolismo , Riñón/patología , Masculino , Modelos Biológicos , Hormona Paratiroidea/sangre , Ratas Wistar , Transducción de Señal , Regulación hacia Arriba
11.
Phys Chem Chem Phys ; 22(6): 3661-3674, 2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32002524

RESUMEN

We have systematically investigated the magnetization reversal characteristics and magnetoresistance of continuous and nanoporous [Co/Pd]5-IrMn multilayered thin films with perpendicular magnetic anisotropy at different temperatures (4-300 K). For their nanostructuring, porosity was induced by means of deposition onto templates of anodized titania with small (∼30 nm in diameter) homogeneously distributed pores. The magnetization reversal and magnetoresistance of the porous films were found to be closely related to the splitting of the ferromagnetic material into regions with different magnetic properties, in correlation with the complex morphology of the porous system. Independent magnetization reversal is detected for these regions, and is accompanied by its strong impact on the magnetic order in the capping IrMn layer. Electron-magnon scattering is found to be a dominant mechanism of magnetoresistance, determining its almost linear field dependence in a high magnetic field and contributing to its magnetoresistance behavior, similar to magnetization reversal, in a low magnetic field. Partial rotation of IrMn magnetic moments, consistent with the magnetization reversal of the ferromagnet, is proposed as an explanation for the two-state resistance behavior observed in switching between high-resistive and low-resistive values at the magnetization reversal of the porous system studied.

12.
J Cell Physiol ; 234(7): 10489-10499, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30426494

RESUMEN

Chronic rhinosinusitis without nasal polyp (CRSsNP) is characterized by tissue remodeling and fibrosis. Transforming growth factor-ß (TGF-ß) is considered a master switch in the induction of the profibrotic program which can induce fibroblasts to synthesize and contract extracellular matrix (ECM) proteins. A previous study has shown TGF-ß1 signaling and collagen overproduction in the CRSsNP, but the responsible cells and mechanism of action remain unclear. Therefore, this study was aimed to investigate the relationship between TGF-ß1 stimulation and collagen expression and to explore the role of connective tissue growth factor (CTGF) during the remodeling process using human CRSsNP nasal mucosa tissues and mucosa-derived fibroblasts as main materials. We found that TGF-ß1 and its isoforms could promote collagen protein expression. Concomitantly, TGF-ß1 caused CTGF expression and secretion. An addition of exogenous CTGF to fibroblasts also caused collagen expression. In accordance with these observations, TGF-ß1, CTGF, and collagen were highly expressed in the subepithelial stroma region of CRSsNP nasal mucosa, as determined by immunohistochemistry. The TGF-ß1-mediated collagen expression could be blocked by actinomycin D and SIS3, suggesting that the induction was through transcriptional regulation and Smad2/3-dependent pathway. Finally, we demonstrated that CTGF small interfering RNA knockdown led to a substantial decrease in TGF-ß1-mediated collagen expression. Collectively, our results provide first and further evidence that TGF-ß1 mediates collagen expression-production through a canonical Smad2/3-dependent pathway and CTGF induction and secretion in human nasal fibroblasts. Moreover, TGF-ß1, CTGF, and collagen are highly expressed in human CRSsNP nasal mucosa specimens, suggesting their roles in tissue remodeling during CRSsNP progression.


Asunto(s)
Colágeno/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Fibroblastos/metabolismo , Mucosa Nasal/metabolismo , Sinusitis/metabolismo , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Células Cultivadas , Fibrosis/metabolismo , Regulación de la Expresión Génica/fisiología , Humanos , Pólipos Nasales/metabolismo , Transducción de Señal/fisiología , Factor de Crecimiento Transformador beta/metabolismo
13.
J Cell Physiol ; 233(9): 7226-7238, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29574744

RESUMEN

Numerous studies have demonstrated that Gram-positive microbiomes play an important role in the pathogenesis and in the way of treatment of chronic rhinosinusitis (CRS). Kinins are inflammatory mediators and one of their receptors, namely bradykinin receptor 1 (BKR1 or B1R), is believed to be induced and involved in inflammation in pathophysiological conditions. In the present study, we investigated the effect of peptidoglycan (PGN), a major cell wall component of G(+) bacteria, on BKR expression and its signaling pathway in nasal fibroblasts from CRS without nasal polyp (CRSsNP). The PGN induced increases in B1R mRNA and protein production. The induction was abolished by the NF-κB and protein kinase A inhibitor. In parallel, the PGN treatment directly activated IκB/NF-κB signaling and CREB phosphorylation. Interestingly, a further analysis suggested no involvement of cAMP/PKA/CREB pathway in this induction. The B1R expression and IκB/NF-κB signaling pathway could be attenuated by Toll-like receptor-2 (TLR2) blocking/neutralizing Ab. In a functional assay, the addition of B1R selective agonist (Des-Arg10 -kallidin) to the fibroblasts after PGN stimulation led to an increase in CXCL8 release and p38 MAPK and ERK1/2 phosphorylation, which could be inhibited by the B1R antagonist. Taken together, our results revealed for the first time that PGN can increase B1R expression in human nasal mucosa-derived fibroblasts through TLR2 activation and NF-κB signaling pathway. This induction functionally leads to MAPKs activation and CXCL8 release upon B1R stimulation. Our results also suggest that a major component of G(+) bacteria can participate in B1R upregulation in nasal mucosa during CRSsNP progression.


Asunto(s)
Fibroblastos/metabolismo , FN-kappa B/metabolismo , Mucosa Nasal/patología , Peptidoglicano/farmacología , Receptor de Bradiquinina B1/metabolismo , Rinitis/patología , Sinusitis/patología , Receptor Toll-Like 2/metabolismo , Enfermedad Crónica , AMP Cíclico/biosíntesis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Humanos , Modelos Biológicos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptor de Bradiquinina B1/genética , Transducción de Señal/efectos de los fármacos
14.
Pharmacology ; 99(5-6): 291-302, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28268217

RESUMEN

The activation of endothelial cells (ECs) and migration of vascular smooth muscle cells (VSMCs) have played a crucial role in monocyte chemotaxis/adhesion and intima thickening during vascular injury and atherosclerosis, respectively. Several phenanthrenes isolated from plants and natural products have been shown to possess different bioactivities such as anti-platelet aggregation and anti-inflammation. The current study was designated to investigate the effects of a phenanthrene derivative, 5,7-dimethoxy-1,4-phenanthrenequinone (DMPQ), on cell adhesion molecule (CAM) expression in vascular ECs and migration in VSMCs. The DMPQ attenuated monocyte-EC interaction but it did not affect monocyte adhesion to matrix. In parallel, DMPQ reduced tumor necrosis factor-α (TNF-α)-induced intercellular adhesion molecule and vascular CAM expression in ECs. DMPQ compromised TNF-α-induced IκB activation, nuclear factor-kappa B (NF-κB) translocation, and NF-κB-DNA complex formation. Moreover, it affected TNF-α- and hydrogen peroxide (H2O2)-induced reactive oxygen species production and IκB activation. These suggest that DMPQ affects CAM expression by affecting NF-κB signaling. Meanwhile, DMPQ could also inhibit platelet-derived growth factor (PDGF)-induced VSMC migration toward collagen by affecting cellular PDGF signaling, including PDGFRß, PLCγ, ERK1/2, and Akt phosphorylation. The VSMC adhesion to collagen and collagen-induced focal adhesion kinase activation during cell adhesion were impaired by DMPQ treatment. This study reveals a phenanthrene derivative-DMPQ-with anti-inflammatory and anti-migratory bioactivity toward vascular ECs and SMCs, suggesting its protective effect on vascular injuries.


Asunto(s)
Moléculas de Adhesión Celular/biosíntesis , Movimiento Celular/efectos de los fármacos , Endotelio Vascular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Fenantrenos/farmacología , Quinonas/farmacología , Adhesión Celular/efectos de los fármacos , Células Cultivadas , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Proteína-Tirosina Quinasas de Adhesión Focal/metabolismo , Humanos , Peróxido de Hidrógeno , Proteínas I-kappa B/metabolismo , Monocitos/metabolismo , Músculo Liso Vascular/citología , Músculo Liso Vascular/metabolismo , FN-kappa B/metabolismo , Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/farmacología
15.
J Asian Nat Prod Res ; 18(5): 443-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26727666

RESUMEN

Two new bisamides, aglaiamides A (1) and B (2), along with three known ones (3-5), were isolated from the leaves of Aglaia perviridis. Their structures were established on the basis of detailed spectroscopic analyses.


Asunto(s)
Aglaia/química , Amidas/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Amidas/química , Benzofuranos/química , Medicamentos Herbarios Chinos/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Hojas de la Planta/química
16.
Cell Physiol Biochem ; 34(4): 1373-84, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25301363

RESUMEN

BACKGROUND/AIMS: The chemokine CXCL1 has been reported to be expressed in lung airway epithelium and non-small cell lung cancer biopsy specimens. In this study, we investigated the effects of TNF-α, an abundant cytokine detected in inflammation and various cancers, on CXCL1 release by human A549 lung carcinoma epithelial cells. METHODS: CXCL1 expression was determined by ELISA and RT-PCR. TNF-α signaling was examined by western blotting. Monocyte migration was assayed by a Transwell migration system. RESULTS: TNF-α stimulated CXCL1 release and mRNA expression, and this release was inhibited by inhibitors of JNK, p38 MAPK, PI-3K/Akt and AP-1 transcription factor. TNF-α treatment was followed by JNK, p38 MAPK and PI3K/Akt activation. However, only the JNK inhibitor could reduce the CXCL1 mRNA level, suggesting that JNK is required mainly for CXCL1 mRNA synthesis, whereas p38 MAPK and PI-3K/Akt might be responsible for CXCL1 secretion. Dexamethasone (dex) and TGF-ß reduced CXCL1 secretion, with dex upregulating the expression of MAP kinase phosphatase-1 and TGF-ß causing smad2/3 activation and nuclear translocation. A functional analysis showed that the released CXCL1 enhanced monocyte migration and could be abolished by a CXCL1 neutralizing antibody and CXCR antagonist. CONCLUSION: We demonstrate that TNF-α induces CXCL1 expression through the JNK, p38 MAPK and PI-3K/Akt signaling pathways in human pulmonary epithelial cells.


Asunto(s)
Quimiocina CXCL1/metabolismo , Células Epiteliales/metabolismo , Pulmón/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Quimiocina CXCL1/genética , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/genética , Transducción de Señal/genética , Proteína Smad2/genética , Proteína Smad2/metabolismo , Proteína smad3/genética , Proteína smad3/metabolismo , Factor de Transcripción AP-1/genética , Factor de Transcripción AP-1/metabolismo , Transcripción Genética/genética , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo , Factor de Necrosis Tumoral alfa/genética , Regulación hacia Arriba/genética , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
17.
J Neurosci Res ; 92(5): 587-96, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24464877

RESUMEN

Mesenchymal stem cells (MSCs) can differentiate into neuronal-like cell types under specific conditions. The classical antioxidant inducers such as ß-mercaptoethanol (BME), butylated hydroxyanisol (BHA), and dimethylsulfoxide (DMSO) are limited in clinical because of toxicity. Resveratrol, a safer, natural antioxidant, can stimulate osteoblastic differentiation of MSCs. However, its effect of inducing MSCs to differentiate into neuronal-like cells is less well studied, and its differentiated mechanisms are not well understood. Sonic hedgehog (Shh) signaling, mediated by the primary cilia, is crucial for embryonic development and tissue differentiation, but relatively little is known about the role of Shh signaling and primary cilia in neuronal-like differentiation of MSCs. Here we show that primary cilia, harboring patched 1 (Ptc1), are present in growth-arrested MSCs and that smoothened (Smo) and Gli1 are present in cytoplasm of MSCs, which are important components of the Shh signaling pathway. After resveratrol induction, MSCs acquire neuronal-like cell morphologies and phenotypes, Smo translocates to the primary cilia, Gli1 enters the nucleus, and expressions of Smo and Gli1 proteins increase, which can be inhibited by cyclopamine, a Smo antagonist. Meanwhile, Smo agonist (SAG) attains similar effects compared with the resveratrol group. These data indicate that resveratrol can induce MSCs to differentiate into neuronal-like cells and activate Shh signaling pathway in the primary cilia. Moreover, the primary cilia and Shh signaling are essential for resveratrol inducing neuronal-like differentiation of MSCs. Our finding is important for understanding the neuronal-like differentiation mechanism of MSCs for resveratrol and promoting its clinical therapeutic utility.


Asunto(s)
Antioxidantes/farmacología , Diferenciación Celular/efectos de los fármacos , Proteínas Hedgehog/metabolismo , Células Madre Mesenquimatosas/efectos de los fármacos , Neuronas/citología , Transducción de Señal/efectos de los fármacos , Estilbenos/farmacología , Animales , Bromodesoxiuridina/metabolismo , Células Cultivadas , Cilios/efectos de los fármacos , Cilios/fisiología , Cilios/ultraestructura , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Microscopía Electrónica de Rastreo , Ratas , Ratas Sprague-Dawley , Resveratrol , Transducción de Señal/fisiología
18.
J Org Chem ; 79(21): 10189-95, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25317950

RESUMEN

The NaBH4 (or TBABH4)-promoted electrochemically reductive cleavage of aryl C-O bonds in diaryl ethers to produce phenols and arenes with high yields and excellent selectivities at room temperature was reported. Air- and water-tolerable, this process also works on the cleavage of aryl alkyl and benzyl ethers. The application to break the ß-O-4, α-O-4, and 4-O-5 lignin model compounds is also illustrated, which highlights the advance toward the goal of lignin conversion.


Asunto(s)
Borohidruros/química , Técnicas Electroquímicas , Éteres/química , Catálisis , Lignina/química , Estructura Molecular , Fenoles/química
19.
Acta Pharmacol Sin ; 35(3): 339-50, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24487964

RESUMEN

AIM: Chemokines usually direct the movement of circulating leukocytes to sites of inflammation or injury. CXCL1/GRO-α has been shown to be upregulated in atherosclerotic lesions and various cancers. The aim of this study was to investigate the mechanisms underlying the TNF-α-induced release of CXCL1 from human vascular endothelial cells in vitro. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with different proinflam-matory mediators and growth factors. CXCL1 expression and secretion were determined using RT-PCR and ELISA, respectively. TNF-α-induced cell signaling was assayed with Western blotting. Cell viability/growth was determined using MTT assay. Monocyte migration was measured with transwell migration assay. RESULTS: Among the 17 mediators and growth factors tested, TNF-α, LPS and thrombin induced marked increase in CXCL1 release from HUVEC cells. TNF-α (2, 5 ng/mL) induced CXCL1 release and mRNA expression in the cells in concentration- and time-dependent manners. TNF-α (5 ng/mL) caused activation of JNK, p38 MAPK, PI3K and Akt, whereas pretreatment with JNK inhibitor (SP600125), p38 MAPK inhibitor (SB202190) or PI-3K inhibitor (LY294002) significantly suppressed TNF-α-induced CXCL1 release from the cells. But only SP600125 significantly reduced TNF-α-induced CXCL1 mRNA expression in the cells. Moreover, dexamethasone (up to 500 nmol/L) failed to affect TNF-α-induced CXCL1 release from the cells. In functional studies, recombinant CXCL1 enhanced HUVEC proliferation, and both recombinant CXCL1 and TNF-α-induced CXCL1 from HUVECs attracted human monocyte migration. CONCLUSION: TNF-α stimulates CXCL1 release from human ECs through JNK-mediated CXCL1 mRNA expression and p38 MAPK- and PI-3K-mediated CXCL1 secretory processes.


Asunto(s)
Quimiocina CXCL1/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Quimiocina CXCL1/genética , Quimiotaxis de Leucocito/efectos de los fármacos , Técnicas de Cocultivo , Relación Dosis-Respuesta a Droga , Células Endoteliales de la Vena Umbilical Humana/inmunología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Monocitos/efectos de los fármacos , Monocitos/inmunología , Monocitos/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Inhibidores de Proteínas Quinasas/farmacología , ARN Mensajero/metabolismo , Factores de Tiempo , Regulación hacia Arriba , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
20.
Biol Pharm Bull ; 37(7): 1191-8, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24989010

RESUMEN

In an effort to develop potent cyclooxygenase-1 (COX-1) inhibitors used as anticancer agent, a series of 2',5'-dimethoxychalcones was screened to evaluate their antiplatelet effect on human washed platelets suspension. Compound 2 exhibited potent inhibition of human washed platelet aggregation induced by collagen, significantly inhibited collagen- and arachidonic acid-induced thromboxane B2 release, and revealed inhibitory effect on COX-1 activity. Molecular docking studies showed that 1, 2, and 4 were bound in the active site of COX-1. These indicated that the antiplatelet effect of these compounds were mainly mediated through the suppression of COX-1 activity and reduced the thromboxane formation. To investigate the mechanistic action of COX-1 inhibitor enhanced the cytotoxic effect against human bladder cancer cells, NTUB1, we assessed the cytotoxic effect of 2 against NTUB1. Treatment of NTUB1 cells with various concentrations of 2 led to a concentration-dependent increase of cell death and decrease of reactive oxygen species levels. The flow-cytometric analysis showed that 2 induced a G1 phase cell cycle arrest but did not accompany an appreciable sub-G1 phase in NTUB1 cells. In addition, compound 2 increased p21 and p27 expressions and did not inhibit the expression of COX-1 in NTUB1 cells. Our results suggested that 2 enhanced cell growth inhibition or antiproliferative activity in NTUB1 cells through G1 arrest by COX-1 independent mechanism.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Chalcona/análogos & derivados , Chalcona/farmacología , Inhibidores de Agregación Plaquetaria/farmacología , Agregación Plaquetaria/efectos de los fármacos , Antineoplásicos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Chalcona/química , Ciclooxigenasa 1/metabolismo , Relación Dosis-Respuesta a Droga , Citometría de Flujo , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Estructura Molecular , Inhibidores de Agregación Plaquetaria/química , Especies Reactivas de Oxígeno/metabolismo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA