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1.
Plant Mol Biol ; 114(4): 77, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38909327

RESUMEN

As self-incompatibility is a major issue in pummelo breeding and production, its mechanism in citrus was analyzed to improve breeding efficiency and reduce production costs. Rutaceae belongs to S-RNase type of gametophytic self-incompatibility. While the function of S-RNase/SLF and the mechanism of self-incompatibility have been studied extensively, the transcriptional regulation of S-RNase has been less studied. We performed transcriptome sequencing with the styles of 'Shatian' pummelo on the day of anthesis and 1-5 days before anthesis, and found that the transcript level of S-RNase gradually decreased with flower development. By analyzing differentially expressed genes and correlation with the expression trend of S-RNase, we identified a candidate gene, CgHSFB1, and utilized biochemical experiments such as yeast one-hybrid assay, electrophoretic mobility shift assay and dual-luciferase assay, as well as transient transformation of citrus calli and Citrus microcarpa and demonstrated that CgHSFB1 could directly bind to the S1-RNase promoter and repress the expression of S1-RNase, which is involved in the pummelo self-incompatibility response. In contrast, CgHSFB1 did not bind to the promoter of S2-RNase, and there was specificity in the regulation of S-RNase.


Asunto(s)
Citrus , Flores , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas , Ribonucleasas , Autoincompatibilidad en las Plantas con Flores , Citrus/genética , Citrus/fisiología , Citrus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Flores/genética , Flores/fisiología , Flores/crecimiento & desarrollo , Autoincompatibilidad en las Plantas con Flores/genética , Ribonucleasas/genética , Ribonucleasas/metabolismo , Regiones Promotoras Genéticas/genética , Transcriptoma , Perfilación de la Expresión Génica
2.
Neoplasma ; 69(1): 174-182, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34846160

RESUMEN

Isochorismatase domain-containing 1 (ISOC1) plays a carcinogenic role in various tumors. However, its expression and role in hepatocellular carcinoma (HCC) have not been elucidated. This is the first study to investigate the involvement of ISOC1 in HCC growth and migration. ISOC1 expression was analyzed using public databases and clinical samples, and clinical specimens were analyzed by real-time quantitative polymerase chain reaction, western blotting, and immunohistochemistry. ISOC1 was also overexpressed in two HCC cell lines (Huh7 and HepG2) to explore how ISOC1 affects HCC cells. Finally, a nude mouse xenograft tumor model was used to investigate the role of ISOC1 in HCC cell tumorigenicity. ISOC1 was downregulated in HCC tissues compared to that in matched paracancerous tissues, and low ISOC1 expression was associated with a poor prognosis. The proliferation and single-cell colony-forming ability of the ISOC1-overexpressing cell lines Huh7 and HepG2 were significantly inhibited. Moreover, ISOC1 overexpression suppressed the migration and invasion abilities of HCC cells in vitro, and ISOC1 upregulation hindered tumor growth in the xenograft tumor model in vivo. Therefore, ISOC1 is a potential HCC suppressor protein.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Hidrolasas , Neoplasias Hepáticas/genética , Ratones
3.
Acta Pharmacol Sin ; 42(1): 132-141, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32404982

RESUMEN

Hsp90 is a potential therapeutic target for tumor, as it maintains the stability of a variety of proteins related to tumor development and progression. Autophagy is a self-degradation process to maintain cellular homeostasis and autophagy inhibitors can suppress tumor growth. In this study, we identified DCZ5248, a triazine derivative, was a dual inhibitor of both Hsp90 and late-autophagy with potent antitumor activity against colon cancer cells in vitro and in vivo. We showed that DCZ5248 (0.1-10 µM) induced dose-dependent degradation of Hsp90 client proteins (AKT, CDK4, CDK6 and RAF-1) in HCT 116 colon cancer cells through a proteasome-dependent pathway. Meanwhile, DCZ5248 (0.3 µM) induced cytoplasmic vacuole formation, LC3 II conversion, p62 protein upregulation, and inhibited autophagy at the late stage in the colon cancer cell lines tested. We further revealed that the inhibition of autophagy was achieved by impairing lysosomal functions through induction of lysosomal acidification and attenuation of lysosomal cathepsin activity. The modulation of autophagy by DCZ5248 was independent of Hsp90 inhibition as the autophagy inhibition was not blocked by Hsp90 knockdown. Importantly, inhibition of both Hsp90 function and autophagy by DCZ5248 induced G1-phase cell cycle arrest, apoptosis, and exerted potent antitumor activity against colon cancer cells both in vitro and in vivo. These findings demonstrate that DCZ5248 is a novel dual inhibitor of Hsp90 and autophagy with potential for colon cancer therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Autofagia/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Triazinas/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Lisosomas/efectos de los fármacos , Ratones Endogámicos BALB C , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Phytopathology ; 111(5): 850-861, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33048631

RESUMEN

Phyllosticta citriasiana is the causal agent of citrus tan spot, an important pomelo disease in Asia. At present, there is little or no information on the epidemiology or population structure of P. citriasiana. By using simple sequence repeat markers, we analyzed 94 isolates from three pomelo production regions in southern and southeastern China. The analyses showed high genetic diversity in each of the three geographic populations. A STRUCTURE analysis revealed two genetic clusters among the 94 isolates; one geographic population was dominated by genotypes in one cluster, and the other two geographic populations were dominated by genotypes of the second cluster. P. citriasiana has a heterothallic mating system with two idiomorphs, MAT1-1 and MAT1-2. Analyses using mating type-specific primers revealed that both mating types were present in all three geographic populations, and in all three populations the mating type ratios were in equilibrium. Although the sexual stage of the fungus has not been discovered yet, analyses of allelic associations indicated evidence for sexual and asexual reproduction within and between populations. Despite the observed genetic differentiation between the three geographic populations, evidence for long-distance gene flow was found.


Asunto(s)
Ascomicetos , Genes del Tipo Sexual de los Hongos , Ascomicetos/genética , Variación Genética , Enfermedades de las Plantas
5.
Appl Opt ; 60(15): C47-C54, 2021 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-34143105

RESUMEN

A compact fiber-coupled hyperspectral imaging sensor (HSIS) operating within the range of ultraviolet to near-infrared (UV-NIR) wavelengths is designed and developed for the remote recording of two-dimensional (2D) spectrally resolved thermal radiation and chemiluminescent emission from ultra-high-temperature ceramics (UHTCs). Using simulations, the entire system is optimized to improve the collection efficiency and minimize aberrations. The design, construction, and characterization of the HSIS sensor are discussed in detail. We present the 2D spectrally resolved measurements of the simultaneous thermal radiation and BO2∗ chemiluminescent emission from a commonly used UHTC (HfB2-SiC) material under high-heat-flux conditions. Our results show that BO2∗ chemiluminescence corresponds directly to material ablation and can be used to track the formation of the protective heat-resistant glass/oxide layer. Furthermore, the temperature measurements demonstrate the heat distribution properties of the sample and indicate the locations at which BO2∗ chemiluminescence is possible. These results highlight the application prospects of the compact fiber-coupled HSIS for high-temperature material characterization in practical arc-jet facilities with limited optical access.

6.
Genes Dev ; 27(20): 2246-58, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24142875

RESUMEN

The RNPC1 RNA-binding protein, also called Rbm38, is a target of p53 and a repressor of p53 mRNA translation. Thus, the p53-RNPC1 loop is critical for modulating p53 tumor suppression, but it is not clear how the loop is regulated. Here, we showed that RNPC1 is phosphorylated at Ser195 by glycogen synthase kinase 3 (GSK3). We also showed that GSK3 promotes p53 mRNA translation through phosphorylation of RNPC1. Interestingly, we found that the phosphor-mimetic mutant S195D and the deletion mutant Δ189-204, which lacks the GSK3 phosphorylation site, are unable to repress p53 mRNA translation due to loss of interaction with eukaryotic translation factor eIF4E on p53 mRNA. Additionally, we found that phosphorylated RNPC1, RNPC1-S195D, and RNPC1(Δ189-204) promote p53 mRNA translation through interaction with eukaryotic translation factor eIF4G, which then facilitates the assembly of the eIF4F complex on p53 mRNA. Furthermore, we showed that upon inhibition of the phosphatidylinositol 3-kinase (PI3K)-Akt pathway, GSK3 is activated, leading to increased RNPC1 phosphorylation and increased p53 expression in a RNPC1-dependent manner. Together, we postulate that the p53-RNPC1 loop can be explored to increase or decrease p53 activity for cancer therapy.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Glucógeno Sintasa Quinasa 3/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteína p53 Supresora de Tumor/genética , Regiones no Traducidas 3'/genética , Línea Celular Tumoral , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta , Células HCT116 , Humanos , Células MCF-7 , Fosfatidilinositol 3-Quinasa/metabolismo , Fosforilación , Unión Proteica , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/metabolismo
7.
J Proteome Res ; 18(6): 2654-2665, 2019 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-31059266

RESUMEN

The deubiquitinase USP9X is involved in multiple diseases including neurodegeneration, epilepsy, and various types of tumors by targeting different substrates. In the present study, we aimed to explore the potential substrates of USP9X and performed SILAC-based quantitative proteomics to compare these substrates in USP9X-knockdown and wild-type HeLa cells. We consequently carried out Flag-NFX1-123 tag affinity-based mass spectrometry and confirmed that the X-box binding nuclear factor NFX1-123 interacted with USP9X. Moreover, immunoprecipitation assays verified a direct interaction between USP9X and NFX1-123. Further experiments confirmed that NFX1-123 could be modified by ubiquitination and that USP9X stabilized NFX1-123 via efficient deubiquitination of NFX1-123. Knockdown of USP9X resulted in decreased NFX1-123 protein levels compared with their unchanged corresponding mRNA levels in different cell lines. In summary, we found that NFX1-123 was a bona fide substrate of the deubiquitinase USP9X and that it could be degraded by the ubiquitin-proteasome system. The present study provided new insight into understanding the biological function of USP9X by targeting its substrate NFX1-123.


Asunto(s)
Degeneración Nerviosa/genética , Proteómica , Proteínas Represoras/genética , Ubiquitina Tiolesterasa/genética , Apoptosis/genética , Proliferación Celular/genética , Regulación de la Expresión Génica/genética , Técnicas de Silenciamiento del Gen , Células HeLa , Humanos , Degeneración Nerviosa/patología , Complejo de la Endopetidasa Proteasomal/genética , Complejo de la Endopetidasa Proteasomal/metabolismo , Ubiquitina/genética , Ubiquitinación/genética
8.
Biochem Biophys Res Commun ; 516(1): 320-326, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31256935

RESUMEN

Kappa-opioid receptor (KOR) is a member of G-protein coupled receptors (GPCRs) expressed in serotonergic neurons and neuronal terminals. The involvement of KOR ligands in nociception, diuresis, emotion, cognition, and immune system has been extensively studied. Omics-based methods are preferable to understand the signaling cascade after KOR activation in a systematic manner. In this study, an in-depth quantitative phosphoproteomic analysis resulted in 305 phosphosites, which were significantly changed in three KOR-overexpressed cells upon treatment with two KOR agonists. The subsequent substrate-kinase prediction analysis revealed that 18 potential kinases might be activated under stimulation of the agonists. We found that phosphorylation of PAK1/2 (p21-activated kinase 1/2) was induced by KOR agonists, resulting in reduced actin stress fibers and cytoskeletal reorganization. In summary, this quantitative phosphoproteomics-based research studied the downstream phosphorylation events upon KOR activation, which may shed light on the investigations of KOR signaling pathway and targeted therapy for KOR-related diseases.


Asunto(s)
Activadores de Enzimas/farmacología , Fosforilación/efectos de los fármacos , Receptores Opioides kappa/agonistas , Quinasas p21 Activadas/metabolismo , Activación Enzimática/efectos de los fármacos , Células HEK293 , Humanos , Proteómica , Receptores Opioides kappa/metabolismo
10.
Acta Pharmacol Sin ; 40(2): 268-278, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29777202

RESUMEN

BRAF and MEK inhibitors have shown remarkable clinical efficacy in BRAF-mutant melanoma; however, most patients develop resistance, which limits the clinical benefit of these agents. In this study, we found that the human melanoma cell clones, A375-DR and A375-TR, with acquired resistance to BRAF inhibitor dabrafenib and MEK inhibitor trametinib, were cross resistant to other MAPK pathway inhibitors. In these resistant cells, phosphorylation of ribosomal protein S6 (rpS6) but not phosphorylation of ERK or p90 ribosomal S6 kinase (RSK) were unable to be inhibited by MAPK pathway inhibitors. Notably, knockdown of rpS6 in these cells effectively downregulated G1 phase-related proteins, including RB, cyclin D1, and CDK6, induced cell cycle arrest, and inhibited proliferation, suggesting that aberrant modulation of rpS6 phosphorylation contributed to the acquired resistance. Interestingly, RSK inhibitor had little effect on rpS6 phosphorylation and cell proliferation in resistant cells, whereas P70S6K inhibitor showed stronger inhibitory effects on rpS6 phosphorylation and cell proliferation in resistant cells than in parental cells. Thus regulation of rpS6 phosphorylation, which is predominantly mediated by BRAF/MEK/ERK/RSK signaling in parental cells, was switched to mTOR/P70S6K signaling in resistant cells. Furthermore, mTOR inhibitors alone overcame acquired resistance and rescued the sensitivity of the resistant cells when combined with BRAF/MEK inhibitors. Taken together, our findings indicate that RSK-independent phosphorylation of rpS6 confers resistance to MAPK pathway inhibitors in BRAF-mutant melanoma, and that mTOR inhibitor-based regimens may provide alternative strategies to overcome this acquired resistance.


Asunto(s)
Resistencia a Antineoplásicos/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteína S6 Ribosómica/metabolismo , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Línea Celular Tumoral , Humanos , Imidazoles/farmacología , Melanoma/tratamiento farmacológico , Melanoma/genética , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Mutación , Oximas/farmacología , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas B-raf/genética , Piridonas/farmacología , Pirimidinonas/farmacología
11.
Gastroenterology ; 149(2): 468-80.e10, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25888330

RESUMEN

BACKGROUND & AIMS: Reactive oxidative species (ROS) are believed to be involved in the progression of nonalcoholic steatohepatitis (NASH). However, little is known about the sources of ROS in hepatocytes or their role in disease progression. We studied the effects of nicotinamide adenine dinucleotide phosphate reduced oxidase 4 (NOX4) in liver tissues from patients with NASH and mice with steatohepatitis. METHODS: Liver biopsy samples were obtained from 5 patients with NASH, as well as 4 patients with simple steatosis and 5 patients without steatosis (controls) from the University of California, Davis Cancer Center Biorepository. Mice with hepatocyte-specific deletion of NOX4 (NOX4(hepKO)) and NOX4(floxp+/+) C57BL/6 mice (controls) were given fast-food diets (supplemented with high-fructose corn syrup) or choline-deficient l-amino acid defined diets to induce steatohepatitis, or control diets, for 20 weeks. A separate group of mice were given the NOX4 inhibitor (GKT137831). Liver tissues were collected and immunoblot analyses were performed determine levels of NOX4, markers of inflammation and fibrosis, double-stranded RNA-activated protein kinase, and phospho-eIF-2α kinase-mediated stress signaling pathways. We performed hyperinsulinemic-euglycemic clamp studies and immunoprecipitation analyses to determine the oxidation and phosphatase activity of PP1C. RESULTS: Levels of NOX4 were increased in patients with NASH compared with controls. Hepatocyte-specific deletion of NOX4 reduced oxidative stress, lipid peroxidation, and liver fibrosis in mice with diet-induced steatohepatitis. A small molecule inhibitor of NOX4 reduced liver inflammation and fibrosis and increased insulin sensitivity in mice with diet-induced steatohepatitis. In primary hepatocytes, NOX4 reduced the activity of the phosphatase PP1C, prolonging activation of double-stranded RNA-activated protein kinase and phosphorylation of extracellular signal-regulated kinase-mediated stress signaling. Mice with hepatocyte-specific deletion of NOX4 and mice given GKT137831 had increased insulin sensitivity. CONCLUSIONS: NOX4 regulates oxidative stress in the liver and its levels are increased in patients with NASH and mice with diet-induced steatohepatitis. Inhibitors of NOX4 reduce liver inflammation and fibrosis and increase insulin sensitivity, and might be developed for treatment of NASH.


Asunto(s)
Hígado Graso/tratamiento farmacológico , Hepatocitos/efectos de los fármacos , Resistencia a la Insulina , Cirrosis Hepática/tratamiento farmacológico , NADPH Oxidasas/metabolismo , NADP/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Biomarcadores/metabolismo , Biopsia , Dieta/métodos , Modelos Animales de Enfermedad , Hígado Graso/inducido químicamente , Hígado Graso/genética , Hígado Graso/metabolismo , Hepatocitos/metabolismo , Humanos , Peroxidación de Lípido/efectos de los fármacos , Hígado/citología , Hígado/patología , Cirrosis Hepática/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADP/administración & dosificación , NADPH Oxidasa 4 , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Proteína Fosfatasa 1/metabolismo , Pirazoles/metabolismo , Pirazolonas , Piridinas/metabolismo , Piridonas , Estrés Fisiológico/efectos de los fármacos
12.
Int J Mol Sci ; 17(9)2016 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-27618015

RESUMEN

The metanephric mesenchyme (MM) cells are a subset of kidney progenitor cells and play an essential role in mesenchymal-epithelial transition (MET), the key step of nephron generation. Six2, a biological marker related to Wnt signaling pathway, promotes the proliferation, inhibits the apoptosis and maintains the un-differentiation of MM cells. Besides, LiCl is an activator of Wnt signaling pathway. However, the role of LiCl in cellular regulation of MM cells remains unclear, and the relationship between LiCl and Six2 in this process is also little known. Here, we performed EdU assay and flow cytometry assay to, respectively, detect the proliferation and apoptosis of MM cells treated with LiCl of increasing dosages. In addition, reverse transcription-PCR (RT-PCR) and Western-blot were conducted to measure the expression of Six2 and some maker genes of Wnt and bone-morphogenetic-protein (BMP) signaling pathway. Furthermore, luciferase assay was also carried out to detect the transcriptional regulation of Six2. Then we found LiCl promoted MM cell proliferation at low-concentration (10, 20, 30, and 40 mM). The expression of Six2 was dose-dependently increased in low-concentration (10, 20, 30, and 40 mM) at both mRNA and protein level. In addition, both of cell proliferation and Six2 expression in MM cells declined when dosage reached high-concentration (50 mM). However, Six2 knock-down converted the proliferation reduction at 50 mM. Furthermore, Six2 deficiency increased the apoptosis of MM cells, compared with negative control cells at relative LiCl concentration. However, the abnormal rise of apoptosis at 30 mM of LiCl concentration implies that it might be the reduction of GSK3ß that increased cell apoptosis. Together, these demonstrate that LiCl can induce the proliferation and apoptosis of MM cells coordinating with Six2.


Asunto(s)
Apoptosis/genética , Proliferación Celular/genética , Proteínas de Homeodominio/metabolismo , Cloruro de Litio/farmacología , Factores de Transcripción/metabolismo , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células HEK293 , Proteínas de Homeodominio/genética , Humanos , Ratones , Factores de Transcripción/genética , Vía de Señalización Wnt
13.
Lab Invest ; 95(10): 1145-56, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26146960

RESUMEN

Hepatocellular carcinoma (HCC) carries a poor prognosis with no effective treatment available other than liver transplantation for selected patients. Vascular invasion of HCC is one of the most important negative predictor of survival. As the regulation of invasion of HCC cells is not well understood, our aim was to study the mechanisms by which galectin 3, a ß-galactosidase-binding lectin mediates HCC cell migration. HCC was induced by N-diethylnitrosamine in wild-type and galectin 3(-/-) mice, and tumor formation, histology, and tumor cell invasion were assessed. The galectin 3(-/-) mice developed significantly smaller tumor burden with a less invasive phenotype than the wild-type animals. Galectin 3 was upregulated in the wild-type HCC tumor tissue, but not in the surrounding parenchyma. Galectin 3 expression in HCC was induced by NF-κB transactivation as determined by chromatin immunoprecipitation assays. In vitro studies assessed the pro-migratory effects of galectin 3. The migration of hepatoma cells was significantly decreased after transfection by the galectin 3 siRNA and also after using the Rho kinase inhibitor Y-27632. The reorganization of the actin cytoskeleton, RhoA GTPase activity and the phosphorylation of MLC2 (myosin light chain 2) were decreased in the galectin 3 siRNA-transfected cells. In addition, in vitro and in vivo evidence showed that galectin 3 deficiency reduced hepatoma cell proliferation and increased their apoptosis rate. In conclusion, galectin 3 is an important lectin that is induced in HCC cells, and promotes hepatoma cell motility and invasion by an autocrine pathway. Targeting galectin 3 therefore could be an important novel treatment strategy to halt disease progression.


Asunto(s)
Carcinoma Hepatocelular/metabolismo , Galectina 3/metabolismo , Neoplasias Hepáticas/metabolismo , Hígado/metabolismo , Quinasa de Cadena Ligera de Miosina/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína de Unión al GTP rhoA/metabolismo , Citoesqueleto de Actina/efectos de los fármacos , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/patología , Animales , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Miosinas Cardíacas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Galectina 3/antagonistas & inhibidores , Galectina 3/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Hígado/efectos de los fármacos , Hígado/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Cadenas Ligeras de Miosina/metabolismo , Quinasa de Cadena Ligera de Miosina/antagonistas & inhibidores , Quinasa de Cadena Ligera de Miosina/química , Invasividad Neoplásica , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Fosforilación/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Quinasas Asociadas a rho/antagonistas & inhibidores , Quinasas Asociadas a rho/metabolismo , Proteína de Unión al GTP rhoA/agonistas , Proteína de Unión al GTP rhoA/antagonistas & inhibidores , Proteína de Unión al GTP rhoA/genética
14.
Hepatology ; 58(4): 1339-48, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23703665

RESUMEN

UNLABELLED: Advanced glycation endproducts (AGEs) accumulate in patients with diabetes, yet the link between AGEs and inflammatory and fibrogenic activity in nonalcoholic steatohepatitis (NASH) has not been explored. Tumor necrosis factor alpha (TNF-α)-converting enzyme (TACE) is at the center of inflammatory processes. Because the main natural regulator of TACE activity is the tissue inhibitor of metalloproteinase 3 (Timp3), we hypothesized that AGEs induce TACE through nicotinamide adenine dinucleotide phosphate reduced oxidase 2 (NOX2); and the down-regulation of Sirtuin 1 (Sirt1)/Timp3 pathways mediate fibrogenic activity in NASH. The role of NOX2, Sirt1, Timp3, and TACE was evaluated in choline-deficient L-amino acid defined (CDAA) or Western diet (WD)-fed wild-type (WT) and NOX2(-/-) mice. To restore Timp3, mice were injected with adenovirus (Ad)-Timp3. Sirt1 and Timp3 expressions were studied in livers from NASH patients, and we found that their levels were significantly lower than in healthy controls. In WT mice on the CDAA or WD, Sirt1 and Timp3 expressions were lower, whereas production of reactive oxidative species and TACE activity significantly increased with an increase in active TNF-α production as well as induction of fibrogenic transcripts. Ad-Timp3 injection resulted in a significant decline in TACE activity, procollagen α1 (I), alpha smooth muscle actin (α-SMA) and transforming growth factor beta (TGF-ß) expression. NOX2(-/-) mice on the CDAA or WD had no significant change in Sirt1, Timp3, and TACE activity or the fibrosis markers assessed. In vitro, AGE exposure decreased Sirt1 and Timp3 in hepatic stellate cells by a NOX2-dependent pathway, and TACE was induced after exposure to AGEs. CONCLUSION: TACE activation is central to the pathogenesis of NASH and is mediated by AGEs through NOX2 induction and down-regulation of Sirt1/Timp3 pathways.


Asunto(s)
Proteínas ADAM/metabolismo , Hígado Graso/complicaciones , Hígado Graso/metabolismo , Productos Finales de Glicación Avanzada/metabolismo , Cirrosis Hepática/etiología , Cirrosis Hepática/metabolismo , Proteína ADAM17 , Actinas/metabolismo , Animales , Estudios de Casos y Controles , Células Cultivadas , Modelos Animales de Enfermedad , Productos Finales de Glicación Avanzada/farmacología , Humanos , Técnicas In Vitro , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Glicoproteínas de Membrana/deficiencia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , NADPH Oxidasa 2 , NADPH Oxidasas/deficiencia , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Enfermedad del Hígado Graso no Alcohólico , Ratas Sprague-Dawley , Transducción de Señal/inmunología , Sirtuina 1/metabolismo , Inhibidor Tisular de Metaloproteinasa-3/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
15.
Food Chem ; 443: 138616, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38306907

RESUMEN

Guangchenpi (GCP), which is the peel of Citrus reticulata 'Chachiensis', is widely used as an herbal medicine, tea and food ingredient in southeast Asia. Prolonging its aging process results in a more pleasant flavor and increases its profitability. Through the integration of sensory evaluation with flavoromic analysis approaches, we evaluated the correlation between the flavor attributes and the profiles of the volatiles and flavonoids of GCP with various aging years. Notably, d-limonene, γ-terpinene, dimethyl anthranilate and α-phellandrene were the characteristic aroma compounds of GCP. Besides, α-phellandrene and nonanal were decisive for consumers' perception of GCP aging time due to changes of their odor activity values (OAVs). The flavor attributes of GCP tea liquid enhanced with the extension of aging time, and limonene-1,2-diol was identified as an important flavor enhancer. Combined with machine learning models, key flavor-related metabolites could be developed as efficient biomarkers for aging years to prevent GCP adulteration.


Asunto(s)
Citrus , Monoterpenos Ciclohexánicos , Limoneno ,
16.
J Biol Chem ; 287(41): 34410-8, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-22908227

RESUMEN

The cyclin-dependent kinase inhibitor p21(Waf1/Cip1) is a major regulator of the cell cycle and plays an important role in many cellular processes, including differentiation, stress response, apoptosis, and tumorigenesis. We previously cloned the gene encoding dog p21 and found that unlike its human ortholog, dog p21 is expressed as two isoforms, one high molecular mass band of 23 kDa and one low molecular mass band of 19 kDa. In the current study, we found that the high molecular mass band is phosphorylated, whereas the low molecular mass band is hypophosphorylated. Moreover, by generating multiple mutants of dog p21, we found that serine 123 and proline 124, which form a consensus site for proline-directed phosphorylation, are required for expression of the high molecular mass p21 isoform through phosphorylation at serine 123. Most importantly, we showed that serine 123 phosphorylation inhibits ubiquitin-independent proteasomal degradation of p21 protein and subsequently, prolongs p21 protein half-life and enhances the ability of p21 to suppress cell proliferation. Taken together, these data reveal that serine 123 phosphorylation modulates p21 protein stability and activity by suppressing ubiquitin-independent proteasomal degradation.


Asunto(s)
Proliferación Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Ubiquitina/metabolismo , Animales , Línea Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Perros , Humanos , Fosforilación/fisiología , Complejo de la Endopetidasa Proteasomal/genética , Isoformas de Proteínas , Estabilidad Proteica , Serina/genética , Serina/metabolismo , Especificidad de la Especie , Ubiquitina/genética
18.
Huan Jing Ke Xue ; 44(8): 4387-4396, 2023 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-37694633

RESUMEN

PAHs (polycyclic aromatic hydrocarbons) accumulated in arable soils have significant impacts on farmland quality and human health, which has attracted wide attention from scientists and the public. A total of 22 arable soil samples were collected from Taiyuan, an old industrial city, including three districts (industrial zones, hilly areas, and sewage irrigation area), and the contents of 21 PAHs were detected using the GC-MS method. The sources of PAHs in soils were analyzed using the diagnostic ratios (DRs) method and positive matrix factorization (PMF) model, and the soil health risks were analyzed using the incremental lifetime cancer risk (ILCR) model. The results indicated that the average concentrations of Σ21PAHs and Σ16PAHs in arable soils of Taiyuan were 934.6 ng·g-1 and 787.7 ng·g-1, respectively, which were lower than the soil pollution risk screening value of agricultural land stipulated in GB 15168-2018. 3-5 rings PAHs were the dominant components, accounting for~90% of the Σ21PAHs. Approximately 60% of sites in industrial zones, 13% in hilly areas, and 33% in the sewage irrigation area had high PAHs contents larger than 1000 ng·g-1. The spatial distribution of PAHs showed that more severe PAHs pollution in the soil occurred in industrial areas than that in the other two districts. The DRs suggested that the combustion of coals, bio-masses, and traffic emissions were the dominant sources for PAHs pollution in arable soils in Taiyuan. The simulation results of the PMF model indicated that the sources and contribution rates of PAHs in cultivated soils were coal and biomass burning sources (59%), traffic sources (22%), and coking sources (19%). The risk assessment confirmed that the arable soils in Taiyuan had high potential carcinogenic risks; thus, more attention should be paid to the PAHs pollutions in arable soils.

19.
Am J Physiol Gastrointest Liver Physiol ; 302(4): G439-46, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22159281

RESUMEN

Hepatic stellate cells (HSC), the key fibrogenic cells of the liver, transdifferentiate into myofibroblasts upon phagocytosis of apoptotic hepatocytes. Galectin-3, a ß-galactoside-binding lectin, is a regulator of the phagocytic process. In this study, our aim was to study the mechanism by which extracellular galectin-3 modulates HSC phagocytosis and activation. The role of galectin-3 in engulfment was evaluated by phagocytosis and integrin binding assays in primary HSC. Galectin-3 expression was studied by real-time PCR and enzyme-linked immunosorbent assay, and in vivo studies were done in wild-type and galectin-3(-/-) mice. We found that HSC from galectin-3(-/-) mice displayed decreased phagocytic activity, expression of transforming growth factor-ß1, and procollagen α1(I). Recombinant galectin-3 reversed this defect, suggesting that extracellular galectin-3 is required for HSC activation. Galectin-3 facilitated the α(v)ß(3) heterodimer-dependent binding, indicating that galectin-3 modulates HSC phagocytosis via cross-linking this integrin and enhancing the tethering of apoptotic cells. Blocking integrin α(v)ß(3) resulted in decreased phagocytosis. Galectin-3 expression and release were induced in active HSC engulfing apoptotic cells, and this was mediated by the nuclear factor-κB signaling. The upregulation of galectin-3 in active HSC was further confirmed in vivo in bile duct-ligated (BDL) rats. Galectin-3(-/-) mice displayed significantly decreased fibrosis, with reduced expression of α-smooth muscle actin and procollagen α1(I) following BDL. In summary, extracellular galectin-3 plays a key role in liver fibrosis by mediating HSC phagocytosis, activation, and subsequent autocrine and paracrine signaling by a feedforward mechanism.


Asunto(s)
Galectina 3/metabolismo , Células Estrelladas Hepáticas/metabolismo , Cirrosis Hepática/metabolismo , Hígado/metabolismo , Fagocitosis/fisiología , Animales , Adhesión Celular/fisiología , Diferenciación Celular/fisiología , Galectina 3/genética , Células Estrelladas Hepáticas/patología , Hígado/patología , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Ratones , Ratones Noqueados , FN-kappa B/genética , FN-kappa B/metabolismo , Transducción de Señal/genética
20.
Front Microbiol ; 13: 812771, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35369462

RESUMEN

Hepatocellular carcinoma (HCC), a primary liver cancer, is closely associated with the gut microbiota. However, the role of gut fungi in the development of HCC remains unclear. The aim of this study was to explore the influence of intestinal Candida albicans on HCC. Here, We found that patients with HCC showed significantly decreased diversity of the gut mycobiome and increased abundance of C. albicans, compared to the patients with liver cirrhosis. The gavage of C. albicans in the WT models increased the tumor size and weight and influenced the plasma metabolome, which was indicated by alterations in 117 metabolites, such as L-carnitine and L-acetylcarnitine, and several KEGG enriched pathways, such as phenylalanine metabolism and citrate cycle. Moreover, the expression of nucleotide oligomerization domain-like receptor family pyrin domain containing 6 (NLRP6) in the intestinal tissues and primary intestinal epithelial cells of the WT mice interacted with C. albicans increased. Notably, the colonization of C. albicans had no effect on tumor growth in Nlrp6 -/- mice. In conclusion, the abnormal colonization of C. albicans reprogrammed HCC metabolism and contributed to the progression of HCC dependent on NLRP6, which provided new targets for the treatment of HCC.

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