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1.
Cell ; 185(9): 1539-1548.e5, 2022 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-35429436

RESUMEN

Virus-like particle (VLP) and live virus assays were used to investigate neutralizing immunity against Delta and Omicron SARS-CoV-2 variants in 259 samples from 128 vaccinated individuals. Following Delta breakthrough infection, titers against WT rose 57-fold and 3.1-fold compared with uninfected boosted and unboosted individuals, respectively, versus only a 5.8-fold increase and 3.1-fold decrease for Omicron breakthrough infection. Among immunocompetent, unboosted patients, Delta breakthrough infections induced 10.8-fold higher titers against WT compared with Omicron (p = 0.037). Decreased antibody responses in Omicron breakthrough infections relative to Delta were potentially related to a higher proportion of asymptomatic or mild breakthrough infections (55.0% versus 28.6%, respectively), which exhibited 12.3-fold lower titers against WT compared with moderate to severe infections (p = 0.020). Following either Delta or Omicron breakthrough infection, limited variant-specific cross-neutralizing immunity was observed. These results suggest that Omicron breakthrough infections are less immunogenic than Delta, thus providing reduced protection against reinfection or infection from future variants.


Asunto(s)
COVID-19 , SARS-CoV-2 , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Vacuna BNT162 , COVID-19/inmunología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos
2.
Cell ; 184(25): 6022-6036.e18, 2021 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-34838159

RESUMEN

Viral-deletion mutants that conditionally replicate and inhibit the wild-type virus (i.e., defective interfering particles, DIPs) have long been proposed as single-administration interventions with high genetic barriers to resistance. However, theories predict that robust, therapeutic DIPs (i.e., therapeutic interfering particles, TIPs) must conditionally spread between cells with R0 >1. Here, we report engineering of TIPs that conditionally replicate with SARS-CoV-2, exhibit R0 >1, and inhibit viral replication 10- to 100-fold. Inhibition occurs via competition for viral replication machinery, and a single administration of TIP RNA inhibits SARS-CoV-2 sustainably in continuous cultures. Strikingly, TIPs maintain efficacy against neutralization-resistant variants (e.g., B.1.351). In hamsters, both prophylactic and therapeutic intranasal administration of lipid-nanoparticle TIPs durably suppressed SARS-CoV-2 by 100-fold in the lungs, reduced pro-inflammatory cytokine expression, and prevented severe pulmonary edema. These data provide proof of concept for a class of single-administration antivirals that may circumvent current requirements to continually update medical countermeasures against new variants.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Virus Interferentes Defectuosos/metabolismo , Replicación Viral/efectos de los fármacos , Animales , Antivirales/farmacología , COVID-19/metabolismo , Línea Celular , Chlorocebus aethiops , Medios de Cultivo Condicionados/farmacología , Virus Interferentes Defectuosos/patogenicidad , Sistemas de Liberación de Medicamentos/métodos , Células Epiteliales , Humanos , Masculino , Mesocricetus , Nanopartículas/uso terapéutico , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidad , Células Vero
3.
Cell ; 184(2): 323-333.e9, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33306959

RESUMEN

The December 2019 outbreak of a novel respiratory virus, SARS-CoV-2, has become an ongoing global pandemic due in part to the challenge of identifying symptomatic, asymptomatic, and pre-symptomatic carriers of the virus. CRISPR diagnostics can augment gold-standard PCR-based testing if they can be made rapid, portable, and accurate. Here, we report the development of an amplification-free CRISPR-Cas13a assay for direct detection of SARS-CoV-2 from nasal swab RNA that can be read with a mobile phone microscope. The assay achieved ∼100 copies/µL sensitivity in under 30 min of measurement time and accurately detected pre-extracted RNA from a set of positive clinical samples in under 5 min. We combined crRNAs targeting SARS-CoV-2 RNA to improve sensitivity and specificity and directly quantified viral load using enzyme kinetics. Integrated with a reader device based on a mobile phone, this assay has the potential to enable rapid, low-cost, point-of-care screening for SARS-CoV-2.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , Teléfono Celular/instrumentación , Imagen Óptica/métodos , ARN Viral/análisis , Carga Viral/métodos , Animales , Prueba de Ácido Nucleico para COVID-19/economía , Prueba de Ácido Nucleico para COVID-19/instrumentación , Sistemas CRISPR-Cas , Línea Celular , Proteínas de la Nucleocápside de Coronavirus/genética , Humanos , Nasofaringe/virología , Imagen Óptica/instrumentación , Fosfoproteínas/genética , Pruebas en el Punto de Atención , Interferencia de ARN , ARN Viral/genética , Sensibilidad y Especificidad , Carga Viral/economía , Carga Viral/instrumentación
4.
Cell ; 184(13): 3426-3437.e8, 2021 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-33991487

RESUMEN

We identified an emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant by viral whole-genome sequencing of 2,172 nasal/nasopharyngeal swab samples from 44 counties in California, a state in the western United States. Named B.1.427/B.1.429 to denote its two lineages, the variant emerged in May 2020 and increased from 0% to >50% of sequenced cases from September 2020 to January 2021, showing 18.6%-24% increased transmissibility relative to wild-type circulating strains. The variant carries three mutations in the spike protein, including an L452R substitution. We found 2-fold increased B.1.427/B.1.429 viral shedding in vivo and increased L452R pseudovirus infection of cell cultures and lung organoids, albeit decreased relative to pseudoviruses carrying the N501Y mutation common to variants B.1.1.7, B.1.351, and P.1. Antibody neutralization assays revealed 4.0- to 6.7-fold and 2.0-fold decreases in neutralizing titers from convalescent patients and vaccine recipients, respectively. The increased prevalence of a more transmissible variant in California exhibiting decreased antibody neutralization warrants further investigation.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , COVID-19/inmunología , COVID-19/transmisión , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Humanos , Mutación/genética , Secuenciación Completa del Genoma/métodos
5.
Nature ; 607(7918): 351-355, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35584773

RESUMEN

SARS-CoV-2 Delta and Omicron are globally relevant variants of concern. Although individuals infected with Delta are at risk of developing severe lung disease, infection with Omicron often causes milder symptoms, especially in vaccinated individuals1,2. The question arises of whether widespread Omicron infections could lead to future cross-variant protection, accelerating the end of the pandemic. Here we show that without vaccination, infection with Omicron induces a limited humoral immune response in mice and humans. Sera from mice overexpressing the human ACE2 receptor and infected with Omicron neutralize only Omicron, but not other variants of concern, whereas broader cross-variant neutralization was observed after WA1 and Delta infections. Unlike WA1 and Delta, Omicron replicates to low levels in the lungs and brains of infected animals, leading to mild disease with reduced expression of pro-inflammatory cytokines and diminished activation of lung-resident T cells. Sera from individuals who were unvaccinated and infected with Omicron show the same limited neutralization of only Omicron itself. By contrast, Omicron breakthrough infections induce overall higher neutralization titres against all variants of concern. Our results demonstrate that Omicron infection enhances pre-existing immunity elicited by vaccines but, on its own, may not confer broad protection against non-Omicron variants in unvaccinated individuals.


Asunto(s)
COVID-19 , Protección Cruzada , SARS-CoV-2 , Vacunación , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19/administración & dosificación , Protección Cruzada/inmunología , Citocinas , Humanos , Ratones , SARS-CoV-2/clasificación , SARS-CoV-2/inmunología , Vacunación/estadística & datos numéricos
6.
Proc Natl Acad Sci U S A ; 119(31): e2200592119, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35858386

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant contains extensive sequence changes relative to the earlier-arising B.1, B.1.1, and Delta SARS-CoV-2 variants that have unknown effects on viral infectivity and response to existing vaccines. Using SARS-CoV-2 virus-like particles (VLPs), we examined mutations in all four structural proteins and found that Omicron and Delta showed 4.6-fold higher luciferase delivery overall relative to the ancestral B.1 lineage, a property conferred mostly by enhancements in the S and N proteins, while mutations in M and E were mostly detrimental to assembly. Thirty-eight antisera samples from individuals vaccinated with Pfizer/BioNTech, Moderna, or Johnson & Johnson vaccines and convalescent sera from unvaccinated COVID-19 survivors had 15-fold lower efficacy to prevent cell transduction by VLPs containing the Omicron mutations relative to the ancestral B.1 spike protein. A third dose of Pfizer vaccine elicited substantially higher neutralization titers against Omicron, resulting in detectable neutralizing antibodies in eight out of eight subjects compared to one out of eight preboosting. Furthermore, the monoclonal antibody therapeutics casirivimab and imdevimab had robust neutralization activity against B.1 and Delta VLPs but no detectable neutralization of Omicron VLPs, while newly authorized bebtelovimab maintained robust neutralization across variants. Our results suggest that Omicron has similar assembly efficiency and cell entry compared to Delta and that its rapid spread is due mostly to reduced neutralization in sera from previously vaccinated subjects. In addition, most currently available monoclonal antibodies will not be useful in treating Omicron-infected patients with the exception of bebtelovimab.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19 , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/uso terapéutico , Anticuerpos Antivirales/uso terapéutico , COVID-19/terapia , COVID-19/virología , Humanos , Mutación , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/genética
7.
PLoS Genet ; 15(8): e1007980, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31381576

RESUMEN

Synaptic structure and activity are sensitive to environmental alterations. Modulation of synaptic morphology and function is often induced by signals from glia. However, the process by which glia mediate synaptic responses to environmental perturbations such as hypoxia remains unknown. Here, we report that, in the mutant for Trachealess (Trh), the Drosophila homolog for NPAS1 and NPAS3, smaller synaptic boutons form clusters named satellite boutons appear at larval neuromuscular junctions (NMJs), which is induced by the reduction of internal oxygen levels due to defective tracheal branches. Thus, the satellite bouton phenotype in the trh mutant is suppressed by hyperoxia, and recapitulated in wild-type larvae raised under hypoxia. We further show that hypoxia-inducible factor (HIF)-1α/Similar (Sima) is critical in mediating hypoxia-induced satellite bouton formation. Sima upregulates the level of the Wnt/Wingless (Wg) signal in glia, leading to reorganized microtubule structures within presynaptic sites. Finally, hypoxia-induced satellite boutons maintain normal synaptic transmission at the NMJs, which is crucial for coordinated larval locomotion.


Asunto(s)
Hipoxia de la Célula/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Drosophila/metabolismo , Unión Neuromuscular/crecimiento & desarrollo , Transmisión Sináptica/fisiología , Factores de Transcripción/metabolismo , Animales , Animales Modificados Genéticamente , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiología , Regulación del Desarrollo de la Expresión Génica , Técnicas de Silenciamiento del Gen , Microscopía Intravital , Larva/fisiología , Locomoción/genética , Microscopía Confocal , Microtúbulos/metabolismo , Modelos Animales , Neuroglía/citología , Neuroglía/metabolismo , Unión Neuromuscular/metabolismo , Terminales Presinápticos/metabolismo , Transducción de Señal/genética , Factores de Transcripción/genética , Regulación hacia Arriba , Proteína Wnt1/metabolismo
8.
Proc Natl Acad Sci U S A ; 116(49): 24651-24661, 2019 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-31666321

RESUMEN

Secreted exosomal microRNAs (miRNAs) mediate interorgan/tissue communications by modulating target gene expression, thereby regulating developmental and physiological functions. However, the source, route, and function in target cells have not been formally established for specific miRNAs. Here, we show that glial miR-274 non-cell-autonomously modulates the growth of synaptic boutons and tracheal branches. Whereas the precursor form of miR-274 is expressed in glia, the mature form of miR-274 distributes broadly, including in synaptic boutons, muscle cells, and tracheal cells. Mature miR-274 is secreted from glia to the circulating hemolymph as an exosomal cargo, a process requiring ESCRT components in exosome biogenesis and Rab11 and Syx1A in exosome release. We further show that miR-274 can function in the neurons or tracheal cells to modulate the growth of synaptic boutons and tracheal branches, respectively. Also, miR-274 uptake into the target cells by AP-2-dependent mechanisms modulates target cell growth. In the target cells, miR-274 down-regulates Sprouty (Sty) through a targeting sequence at the sty 3' untranslated region, thereby enhancing MAPK signaling and promoting cell growth. miR-274 expressed in glia of an mir-274 null mutant is released as an exosomal cargo in the circulating hemolymph, and such glial-specific expression resets normal levels of Sty and MAPK signaling and modulates target cell growth. mir-274 mutant larvae are hypersensitive to hypoxia, which is suppressed by miR-274 expression in glia or by increasing tracheal branches. Thus, glia-derived miR-274 coordinates growth of synaptic boutons and tracheal branches to modulate larval hypoxia responses.


Asunto(s)
Proteínas de Drosophila/genética , Drosophila melanogaster/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas de la Membrana/genética , MicroARNs/metabolismo , Neuroglía/metabolismo , Regiones no Traducidas 3'/genética , Animales , Animales Modificados Genéticamente , Hipoxia de la Célula/genética , Regulación hacia Abajo , Exosomas/metabolismo , Femenino , Hemolinfa/metabolismo , Larva/crecimiento & desarrollo , Larva/metabolismo , Sistema de Señalización de MAP Quinasas/genética , MicroARNs/genética , Mutación , Terminales Presinápticos/metabolismo , Precursores del ARN/genética , Precursores del ARN/metabolismo , Tráquea/crecimiento & desarrollo , Tráquea/metabolismo , Regulación hacia Arriba
9.
Int J Mol Sci ; 23(13)2022 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-35806401

RESUMEN

Acute myeloid leukemia (AML) is characterized by the dysregulation of hematopoietic cell proliferation, resulting in the accumulation of immature myeloid cells in bone marrow. 5-Demethylnobiletin (5-demethyl NOB), a citrus 5-hydroxylated polymethoxyflavone, has been reported to exhibit various bioactivities, such as antioxidant, anti-inflammatory and anticancer properties. In this study, we investigated the antileukemic effects of 5-demethyl NOB and its underlying molecular mechanisms in human AML cells. We found that 5-demethyl NOB (20−80 µM) significantly reduced human leukemia cell viability, and the following trend of effectiveness was observed: THP-1 ≈ U-937 > HEL > HL-60 > K562 cells. 5-Demethyl NOB (20 and 40 µM) modulated the cell cycle through the regulation of p21, cyclin E1 and cyclin A1 expression and induced S phase arrest. 5-Demethyl NOB also promoted leukemia cell apoptosis and differentiation. Microarray-based transcriptome, Gene Ontology (GO) and Gene Set Enrichment Analysis (GSEA) of differentially expressed genes (DEGs) analysis showed that the expression of inhibitor of differentiation/DNA binding 1 (ID1), a gene associated with the GO biological process (BP) cell population proliferation (GO: 0008283), was most strongly suppressed by 5-demethyl NOB (40 µM) in THP-1 cells. We further demonstrated that 5-demethyl NOB-induced ID1 reduction was associated with the inhibition of leukemia cell growth. Moreover, DEGs involved in the hallmark gene set NF-κB/TNF-α signaling pathway were markedly enriched and downregulated by 5-demethyl NOB. Finally, we demonstrated that 5-demethyl NOB (20 and 40 µM), combined with cytarabine, synergistically reduced THP-1 and U-937 cell viability. Our current findings support that 5-demethyl NOB dramatically suppresses leukemia cell proliferation and may serve as a potential phytochemical for human AML chemotherapy.


Asunto(s)
Flavonas , Proteína 1 Inhibidora de la Diferenciación , Leucemia Mieloide Aguda , FN-kappa B , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Flavonas/farmacología , Humanos , Proteína 1 Inhibidora de la Diferenciación/biosíntesis , Proteína 1 Inhibidora de la Diferenciación/genética , Proteína 1 Inhibidora de la Diferenciación/metabolismo , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacología
10.
Int J Mol Sci ; 23(20)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36293338

RESUMEN

Nobiletin, a dietary citrus flavonoid, exerts biological activities against hyperlipidemia, obesity, and atherosclerotic cardiovascular diseases (ASCVDs). The aim of this study was to explore the lipid-lowering effects of nobiletin and the underlying molecular mechanisms in vitro in hepatic cells and in vivo in zebrafish models. Transcriptome and gene ontology (GO) analyses of differentially expressed genes (DEGs) by gene set enrichment analysis (GSEA) showed that a set of twenty-eight core enrichment DEGs associated with "GO BP regulation of lipid metabolic process" (GO: 0019216) were significantly downregulated in nobiletin-treated cells. Among these genes, angiopoietin-like 3 (ANGPTL3), an inhibitor of lipoprotein lipase (LPL) activity that regulates TG-rich lipoprotein (TGRL) metabolism in circulation, was the protein most markedly downregulated by nobiletin. Nobiletin (20 and 40 µM) significantly reduced the levels of ANGPTL3 mRNA and intracellular and secreted ANGPTL3 proteins in hepatic cell lines. Furthermore, alleviation of secreted ANGPTL3 production by nobiletin was found to reinstate LPL catalytic activity. Nobiletin significantly inhibited ANGPTL3 promoter activity and attenuated the transcription factor liver X receptor-α (LXRα)-mediated ANGPTL3 transcription. Molecular docking analysis predicted that nobiletin could bind to the ligand-binding domain of LXRα, thereby counteracting LXRα activation. In animal studies, orally administered nobiletin significantly alleviated the levels of plasma triglycerides (TGs) and cholesterol in zebrafish fed a high-fat diet. Moreover, nobiletin significantly reduced the amounts of hepatic ANGPTL3 protein in zebrafish. Our findings suggest that nobiletin may regulate the LXRα-ANGPTL3-LPL axis and exhibit lipid-modulating effects in vitro and in vivo. Thus, nobiletin is a potential ANGPTL3 inhibitor for the regulation of lipid metabolism to ameliorate dyslipidemia and ASCVDs.


Asunto(s)
Proteína 3 Similar a la Angiopoyetina , Citrus , Animales , Proteínas Similares a la Angiopoyetina/genética , Proteínas Similares a la Angiopoyetina/metabolismo , Lipoproteína Lipasa/metabolismo , Pez Cebra/genética , Receptores X del Hígado/genética , Flavonoides/farmacología , Citrus/metabolismo , Simulación del Acoplamiento Molecular , Ligandos , Triglicéridos/metabolismo , Hepatocitos/metabolismo , Angiopoyetinas/metabolismo , Lipoproteínas , ARN Mensajero , Factores de Transcripción
11.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-34298929

RESUMEN

Dyslipidemia is characterized by increasing plasma levels of low-density lipoprotein-cholesterol (LDL-C), triglycerides (TGs) and TG-rich lipoproteins (TGRLs) and is a major risk factor for the development of atherosclerotic cardiovascular disorders (ASCVDs). It is important to understand the metabolic mechanisms underlying dyslipidemia to develop effective strategies against ASCVDs. Angiopoietin-like 3 (ANGPTL3), a member of the angiopoietin-like protein family exclusively synthesized in the liver, has been demonstrated to be a critical regulator of lipoprotein metabolism to inhibit lipoprotein lipase (LPL) activity. Genetic, biochemical, and clinical studies in animals and humans have shown that loss of function, inactivation, or downregulated expression of ANGPTL3 is associated with an obvious reduction in plasma levels of TGs, LDL-C, and high-density lipoprotein-cholesterol (HDL-C), atherosclerotic lesions, and the risk of cardiovascular events. Therefore, ANGPTL3 is considered an alternative target for lipid-lowering therapy. Emerging studies have focused on ANGPTL3 inhibition via antisense oligonucleotides (ASOs) and monoclonal antibody-based therapies, which have been carried out in mouse or monkey models and in human clinical studies for the management of dyslipidemia and ASCVDs. This review will summarize the current literature on the important role of ANGPTL3 in controlling lipoprotein metabolism and dyslipidemia, with an emphasis on anti-ANGPTL3 therapies as a potential strategy for the treatment of dyslipidemia and ASCVDs.


Asunto(s)
Proteínas Similares a la Angiopoyetina/metabolismo , Dislipidemias/metabolismo , Lipoproteínas/metabolismo , Animales , Aterosclerosis/metabolismo , HDL-Colesterol/metabolismo , LDL-Colesterol , Humanos , Triglicéridos/metabolismo
12.
Int J Mol Sci ; 22(18)2021 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-34576019

RESUMEN

The excessive accumulation of TG-rich lipoproteins (TGRLs) in plasma is associated with dyslipidemia and atherosclerotic cardiovascular diseases (ASCVDs). Tangeretin is a bioactive pentamethoxyflavone mainly found in citrus peels, and it has been reported to protect against hyperlipidemia, diabetes, and obesity. The aim of this study was to investigate the lipid-modulating effects and the underlying mechanisms of tangeretin action in hepatic cells. Transcriptome and bioinformatics analyses with the Gene Ontology (GO) database showed that tangeretin significantly regulated a set of 13 differentially expressed genes (DEGs) associated with the regulation of lipoprotein lipase (LPL) activity. Among these DEGs, angiopoietin-like 3 (ANGPTL3), an essential inhibitor of LPL catalytic activity that regulates TGRL metabolism in plasma, was markedly downregulated by tangeretin. We demonstrated that tangeretin significantly inhibited the mRNA expression of ANGPTL3 in HepG2 and Huh-7 cells. Tangeretin treatment of hepatic cells also reduced the levels of both intracellular and secreted ANGPTL3 proteins. Moreover, we found that inhibition of ANGPTL3 production by tangeretin augmented LPL activity. We further demonstrated that the transcriptional activity of the ANGPTL3 promoter was significantly attenuated by tangeretin, and we identified a DNA element located between the -250 and -121 positions that responded to tangeretin. Furthermore, we found that tangeretin did not alter the levels of the nuclear liver X receptor α (LXRα) protein, an essential transcription factor that binds to the tangeretin-responsive element, but it can counteract LXRα-mediated ANGPTL3 transcription. On the basis of molecular docking analysis, tangeretin was predicted to bind to the ligand-binding domain of LXRα, which would result in suppression of LXRα activation. Our findings support the hypothesis that tangeretin exerts a lipid-lowering effect by modulating the LXRα-ANGPTL3-LPL pathway, and thus, it can be used as a potential phytochemical for the prevention or treatment of dyslipidemia.


Asunto(s)
Proteínas Similares a la Angiopoyetina/antagonistas & inhibidores , Flavonas/farmacología , Metabolismo de los Lípidos/efectos de los fármacos , Receptores X del Hígado/metabolismo , Proteína 3 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina/metabolismo , Evaluación Preclínica de Medicamentos , Dislipidemias/tratamiento farmacológico , Flavonas/uso terapéutico , Células Hep G2 , Humanos , Lipasa/metabolismo
13.
Bioorg Chem ; 98: 103689, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32171993

RESUMEN

In an effort to develop new cancer therapeutics, we have reported clinical candidate BPR1K871 (1) as a potentanticancercompound in MOLM-13 and MV4-11 leukemia models, as well as in colorectal and pancreatic animal models. As BPR1K871 lacks oral bioavailability, we continued searching for orally bioavailable analogs through drug-like property optimization. We optimized both the physicochemical properties (PCP) as well as in vitro rat liver microsomal stability of 1, with concomitant monitoring of aurora kinase enzyme inhibition as well as cellular anti-proliferative activity in HCT-116 cell line. Structural modification at the 6- and 7-position of quinazoline core of 1 led to the identification of 34 as an orally bioavailable (F% = 54) multi-kinase inhibitor, which exhibits potent anti-proliferative activity against various cancer cell lines. Quinazoline 34 is selected as a promising oral lead candidate for further preclinical evaluation.


Asunto(s)
Antineoplásicos/farmacología , Aurora Quinasas/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Aurora Quinasas/metabolismo , Disponibilidad Biológica , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HCT116 , Humanos , Masculino , Estructura Molecular , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/química , Quinazolinas/administración & dosificación , Quinazolinas/química , Ratas , Ratas Sprague-Dawley , Relación Estructura-Actividad
14.
PLoS Genet ; 12(10): e1006362, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27736876

RESUMEN

In response to environmental and physiological changes, the synapse manifests plasticity while simultaneously maintains homeostasis. Here, we analyzed mutant synapses of henji, also known as dbo, at the Drosophila neuromuscular junction (NMJ). In henji mutants, NMJ growth is defective with appearance of satellite boutons. Transmission electron microscopy analysis indicates that the synaptic membrane region is expanded. The postsynaptic density (PSD) houses glutamate receptors GluRIIA and GluRIIB, which have distinct transmission properties. In henji mutants, GluRIIA abundance is upregulated but that of GluRIIB is not. Electrophysiological results also support a GluR compositional shift towards a higher IIA/IIB ratio at henji NMJs. Strikingly, dPAK, a positive regulator for GluRIIA synaptic localization, accumulates at the henji PSD. Reducing the dpak gene dosage suppresses satellite boutons and GluRIIA accumulation at henji NMJs. In addition, dPAK associated with Henji through the Kelch repeats which is the domain essential for Henji localization and function at postsynapses. We propose that Henji acts at postsynapses to restrict both presynaptic bouton growth and postsynaptic GluRIIA abundance by modulating dPAK.


Asunto(s)
Proteínas de Drosophila/genética , Unión Neuromuscular/genética , Receptores de Glutamato/genética , Receptores Ionotrópicos de Glutamato/genética , Sinapsis/genética , Quinasas p21 Activadas/genética , Animales , Moléculas de Adhesión Celular Neuronal/genética , Drosophila melanogaster/genética , Drosophila melanogaster/ultraestructura , Secuencia Kelch/genética , Microscopía Electrónica de Transmisión , Unión Neuromuscular/ultraestructura , Terminales Presinápticos/metabolismo , Sinapsis/ultraestructura , Transmisión Sináptica/genética
15.
Molecules ; 24(3)2019 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-30704067

RESUMEN

Pigeon pea (Cajanus cajan (L.) Millsp.) is a legume crop consumed as an indigenous vegetable in the human diet and a traditional medicinal plant with therapeutic properties. The current study highlights the cholesterol-modulating effect and underlying mechanisms of the methanol extract of Cajanus cajan L. leaves (MECC) in HepG2 cells. We found that MECC increased the LDLR expression, the cell-surface LDLR levels and the LDL uptake activity in HepG2 cells. We further demonstrated that MECC suppressed the proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA and protein expression, but not affected the expression of other cholesterol or lipid metabolism-related genes including inducible degrader of LDLR (IDOL), HMG-CoA reductase (HMGCR), fatty acid synthase (FASN), acetyl-CoA carboxylase (ACC1), and liver X receptor-α (LXR-α) in HepG2 cells. Furthermore, we demonstrated that MECC down-regulated the PCSK9 gene expression through reducing the amount of nuclear hepatocyte nuclear factor-1α (HNF-1α), a major transcriptional regulator for activation of PCSK9 promoter, but not that of nuclear sterol-responsive element binding protein-2 (SREBP-2) in HepG2 cells. Finally, we identified the cajaninstilbene acid, a main bioactive stilbene component in MECC, which significantly modulated the LDLR and PCSK9 expression in HepG2 cells. Our current data suggest that the cajaninstilbene acid may contribute to the hypocholesterolemic activity of Cajanus cajan L. leaves. Our findings support that the extract of Cajanus cajan L. leaves may serve as a cholesterol-lowering agent.


Asunto(s)
Cajanus/química , Colesterol/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Extractos Vegetales/farmacología , Proproteína Convertasa 9/genética , Receptores de LDL/genética , Biomarcadores , Genes Reporteros , Células Hep G2 , Humanos , Lipogénesis/efectos de los fármacos , Hojas de la Planta/química , Regiones Promotoras Genéticas , Proproteína Convertasa 9/metabolismo , ARN Mensajero/genética , Receptores de LDL/metabolismo , Activación Transcripcional
16.
Int J Mol Sci ; 19(4)2018 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-29649138

RESUMEN

Luteolin, a flavonoid nutraceutical abundant in vegetables and fruits, exhibits a wide range of bioactive properties, including antioxidant, anti-inflammatory and anti-cancer activities. Pituitary tumor-transforming gene 1 (PTTG1), an oncoprotein that regulates cell proliferation, is highly expressed in several types of cancer cells including leukemia. In this study, we aim to investigate the anti-cancer effects of luteolin on cells with differential PTTG1 expression and their underlying mechanisms in human myeloid leukemia cells. Methyl thiazolyl tetrazolium (MTT) assay data showed that luteolin (25-100 µM) significantly reduced cell viability in THP-1, HL-60 and K562 cells but did not affect normal peripheral blood mononuclear cells (PBMCs). Flow cytometric analysis and Western blot data demonstrated that luteolin induced a stronger apoptosis on undifferentiated myeloid leukemia cells with higher PTTG1 protein levels than on 12-myristate 13-acetate (PMA)- or all-trans-retinoic acid (ATRA)-differentiated cells with lower PTTG1 expression. Furthermore, PTTG1 knockdown by shRNA in leukemia cells suppressed cell proliferation, arrested cell-cycle progression and impaired the effectiveness of luteolin on cell-cycle regulation. Moreover, PTTG1-knockdown cells with luteolin exposure presented a reduction of the apoptotic proteins and maintained higher levels of the anti-apoptotic proteins such as Mcl-1, Bcl-2 and p21, which exhibited greater resistance to apoptosis. Finally, microarray analysis showed that 20 genes associated with cell proliferation, such as CXCL10, VEGFA, TNF, TP63 and FGFR1, were dramatically down-regulated in PTTG1-knockdown cells. Our current findings clearly demonstrate that luteolin-triggered leukemic cell apoptosis is modulated by the differential expression of the PTTG1. PTTG1 oncoprotein overexpression may modulate cell proliferation-related regulators and enhance the response of myeloid leukemia cells to luteolin. Luteolin is beneficial for the treatment of cancer cells with highly expressed PTTG1 oncoprotein.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Leucemia Mieloide/genética , Luteolina/farmacología , Securina/genética , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes , Células HL-60 , Humanos , Células K562 , Leucemia Mieloide/tratamiento farmacológico , Leucemia Mieloide/metabolismo , Securina/metabolismo , Células THP-1
17.
Biomed Chromatogr ; 30(9): 1449-57, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26873449

RESUMEN

Cinnamon bark (Rou Gui in Chinese), cinnamon twig (Gui Zhi) and shaved cinnamon bark (Gui Sin) have been widely used as spices and in traditional Chinese medicine since ancient times. On-going issues related to quality and authenticity necessitate the development of analytical methods capable of providing an objective evaluation of samples. In this study, chemical fingerprints of cinnamon bark, cinnamon twigs and shaved cinnamon bark were established using liquid chromatography quadruple time-of-flight mass spectrometry in conjunction with principal component analysis (PCA). From 125 samples of cinnamon, we identified the following eight compounds and their the detection ratios: coumarin, cinnamaldehyde, cinnamyl alcohol, cinnamic acid, 2-hydroxycinnamaldehyde, 2-hydroxycinnamic acid, 2-methoxycinnamaldehyde and 4-methoxycinnamaldehyde. Of these, 4-methoxycinnamaldehyde presented the largest variations in detection ratio, making up 64.0, 97.4 and 50.0% in cinnamon bark, cinnamon twig, and shaved cinnamon bark, respectively. The quantities of cinnamyl alcohol, coumarin and cinnamaldehyde also varied between the three parts of the plant. Chemical fingerprints of the three cinnamon samples were established using principal component analysis, the results of which indicate that cinnamon bark and shaved cinnamon bark could be easily differentiated, despite a marked similarity in outward appearance. Cinnamon twig was also shown to depart from the other clusters. The proposed method provides a fast and efficient means of identifying cinnamon herbs for quality control purposes. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Cromatografía Liquida/métodos , Cinnamomum aromaticum , Espectrometría de Masas/métodos , Estructuras de las Plantas , Estándares de Referencia
18.
J Health Psychol ; : 13591053231223930, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38196159

RESUMEN

This study aims to examine changes in body image (BI) over time and factors related to BI among patients with prostate cancer who receive hormone therapy (HT). A cross-sectional design and longitudinal design were utilized. Patients with prostate cancer who received HT were recruited from the urology outpatient departments in two hospitals in Taiwan between August 2017 and December 2020. Cross-sectional data were collected from 177 patients who had started HT for prostate cancer. Longitudinal data were collected from 34 newly diagnosed patients before receiving HT and at 1, 3, 6, and 12 months after HT. The variables measured included hormonal symptoms and distress, self-efficacy, and BI. The results showed that BI dissatisfaction ranged from 6.1% to 17.2%. Hormonal symptoms and distress (e.g. lack of vitality) were correlated with BI dissatisfaction. Education on the side effects of HT and coping strategies can be provided to patients to prevent BI dissatisfaction.

19.
Biomed Pharmacother ; 174: 116598, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38615609

RESUMEN

Angiopoietin-like 3 (ANGPTL3) acts as an inhibitor of lipoprotein lipase (LPL), impeding the breakdown of triglyceride-rich lipoproteins (TGRLs) in circulation. Targeting ANGPTL3 is considered a novel strategy for improving dyslipidemia and atherosclerotic cardiovascular diseases (ASCVD). Hops (Humulus lupulus L.) contain several bioactive prenylflavonoids, including xanthohumol (Xan), isoxanthohumol (Isoxan), 6-prenylnaringenin (6-PN), and 8-prenylnaringenin (8-PN), with the potential to manage lipid metabolism. The aim of this study was to investigate the lipid-lowering effects of Xan, the effective prenylated chalcone in attenuating ANGPTL3 transcriptional activity, both in vitro using hepatic cells and in vivo using zebrafish models, along with exploring the underlying mechanisms. Xan (10 and 20 µM) significantly reduced ANGPTL3 mRNA and protein expression in HepG2 and Huh7 cells, leading to a marked decrease in secreted ANGPTL3 proteins via hepatic cells. In animal studies, orally administered Xan significantly alleviated plasma triglyceride (TG) and cholesterol levels in zebrafish fed a high-fat diet. Furthermore, it reduced hepatic ANGPTL3 protein levels and increased LPL activity in zebrafish models, indicating its potential to modulate lipid profiles in circulation. Furthermore, molecular docking results predicted that Xan exhibits a higher binding affinity to interact with liver X receptor α (LXRα) and retinoic acid X receptor (RXR) than their respective agonists, T0901317 and 9-Cis-retinoic acid (9-Cis-RA). We observed that Xan suppressed hepatic ANGPTL3 expression by antagonizing the LXRα/RXR-mediated transcription. These findings suggest that Xan ameliorates dyslipidemia by modulating the LXRα/RXR-ANGPTL3-LPL axis. Xan represents a novel potential inhibitor of ANGPTL3 for the prevention or treatment of ASCVD.


Asunto(s)
Proteína 3 Similar a la Angiopoyetina , Dieta Alta en Grasa , Flavonoides , Metabolismo de los Lípidos , Lipoproteína Lipasa , Receptores X del Hígado , Propiofenonas , Pez Cebra , Animales , Receptores X del Hígado/metabolismo , Propiofenonas/farmacología , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Dieta Alta en Grasa/efectos adversos , Flavonoides/farmacología , Lipoproteína Lipasa/metabolismo , Receptores X Retinoide/metabolismo , Células Hep G2 , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Chalconas/farmacología , Hígado/efectos de los fármacos , Hígado/metabolismo
20.
Sci Rep ; 14(1): 15351, 2024 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-38961189

RESUMEN

As SARS-CoV-2 continues to spread worldwide, tractable primary airway cell models that recapitulate the cell-intrinsic response to arising viral variants are needed. Here we describe an adult stem cell-derived human airway organoid model overexpressing the ACE2 receptor (ACE2-OE) that supports robust viral replication while maintaining 3D architecture and cellular diversity of the airway epithelium. ACE2-OE organoids were infected with SARS-CoV-2 variants and subjected to single-cell RNA-sequencing. Interferon-lambda was upregulated in cells with low-level infection while the NF-kB inhibitor alpha gene (encoding IkBa) was consistently upregulated in infected cells, and its expression positively correlated with infection levels. Confocal microscopy showed more IkBa expression in infected than bystander cells, but found concurrent nuclear translocation of NF-kB that IkBa usually prevents. Overexpressing a nondegradable IkBa mutant reduced NF-kB translocation and increased viral infection. These data demonstrate the functionality of ACE2-OE organoids in SARS-CoV-2 research and underscore that the strength of the NF-kB feedback loop in infected cells controls viral replication.


Asunto(s)
Enzima Convertidora de Angiotensina 2 , COVID-19 , Inhibidor NF-kappaB alfa , Organoides , SARS-CoV-2 , Replicación Viral , Humanos , Organoides/virología , Organoides/metabolismo , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/genética , SARS-CoV-2/fisiología , COVID-19/virología , COVID-19/metabolismo , COVID-19/genética , Inhibidor NF-kappaB alfa/metabolismo , Inhibidor NF-kappaB alfa/genética , FN-kappa B/metabolismo
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