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1.
Cell ; 167(3): 709-721.e12, 2016 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-27768892

RESUMEN

Chromatin remodelers regulate genes by organizing nucleosomes around promoters, but their individual contributions are obfuscated by the complex in vivo milieu of factor redundancy and indirect effects. Genome-wide reconstitution of promoter nucleosome organization with purified proteins resolves this problem and is therefore a critical goal. Here, we reconstitute four stages of nucleosome architecture using purified components: yeast genomic DNA, histones, sequence-specific Abf1/Reb1, and remodelers RSC, ISW2, INO80, and ISW1a. We identify direct, specific, and sufficient contributions that in vivo observations validate. First, RSC clears promoters by translating poly(dA:dT) into directional nucleosome removal. Second, partial redundancy is recapitulated where INO80 alone, or ISW2 at Abf1/Reb1sites, positions +1 nucleosomes. Third, INO80 and ISW2 each align downstream nucleosomal arrays. Fourth, ISW1a tightens the spacing to canonical repeat lengths. Such a minimal set of rules and proteins establishes core mechanisms by which promoter chromatin architecture arises through a blend of redundancy and specialization.


Asunto(s)
Ensamble y Desensamble de Cromatina , Nucleosomas/química , Nucleosomas/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Adenosina Trifosfatasas/química , Adenosina Trifosfatasas/genética , Cromatina/química , Cromatina/genética , ADN de Hongos/química , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Genoma Fúngico , Histonas/química , Histonas/genética , Poli dA-dT/química , Biosíntesis de Proteínas , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Factores de Transcripción/química , Factores de Transcripción/genética
2.
BMC Microbiol ; 23(1): 35, 2023 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-36732713

RESUMEN

BACKGROUND: Electronic cigarettes (ECs) have been widely used by young individuals in the U.S. while being considered less harmful than conventional tobacco cigarettes. However, ECs have increasingly been regarded as a health risk, producing detrimental chemicals that may cause, combined with poor oral hygiene, substantial inflammation in gingival and subgingival sites. In this paper, we first report that EC smoking significantly increases the odds of gingival inflammation. Then, through mediation analysis, we seek to identify and explain the mechanism that underlies the relationship between EC smoking and gingival inflammation via the oral microbiome. METHODS: We collected saliva and subgingival samples from 75 EC users and 75 non-users between 18 and 34 years in age and profiled their microbial compositions via 16S rRNA amplicon sequencing. We conducted raw sequence data processing, denoising and taxonomic annotations using QIIME2 based on the expanded human oral microbiome database (eHOMD). We then created functional annotations (i.e., KEGG pathways) using PICRUSt2. RESULTS: We found significant increases in α-diversity for EC users and disparities in ß-diversity between EC users and non-users. We also found significant disparities between EC users and non-users in the relative abundance of 36 microbial taxa in the saliva site and 71 microbial taxa in the subgingival site. Finally, we found that 1 microbial taxon in the saliva site and 18 microbial taxa in the subgingival site significantly mediated the effects of EC smoking on gingival inflammation. The mediators on the genus level, for example, include Actinomyces, Rothia, Neisseria, and Enterococcus in the subgingival site. In addition, we report significant disparities between EC users and non-users in the relative abundance of 71 KEGG pathways in the subgingival site. CONCLUSIONS: These findings reveal that continued EC use can further increase microbial dysbiosis that may lead to periodontal disease. Our findings also suggest that continued surveillance for the effect of ECs on the oral microbiome and its transmission to oral diseases is needed.


Asunto(s)
Fumar Cigarrillos , Sistemas Electrónicos de Liberación de Nicotina , Gingivitis , Microbiota , Humanos , Saliva , ARN Ribosómico 16S/genética , Nicotiana/genética , Inflamación
3.
Nature ; 530(7588): 113-6, 2016 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-26814966

RESUMEN

ATP-dependent chromatin remodellers allow access to DNA for transcription factors and the general transcription machinery, but whether mammalian chromatin remodellers target specific nucleosomes to regulate transcription is unclear. Here we present genome-wide remodeller-nucleosome interaction profiles for the chromatin remodellers Chd1, Chd2, Chd4, Chd6, Chd8, Chd9, Brg1 and Ep400 in mouse embryonic stem (ES) cells. These remodellers bind one or both full nucleosomes that flank micrococcal nuclease (MNase)-defined nucleosome-free promoter regions (NFRs), where they separate divergent transcription. Surprisingly, large CpG-rich NFRs that extend downstream of annotated transcriptional start sites are nevertheless bound by non-nucleosomal or subnucleosomal histone variants (H3.3 and H2A.Z) and marked by H3K4me3 and H3K27ac modifications. RNA polymerase II therefore navigates hundreds of base pairs of altered chromatin in the sense direction before encountering an MNase-resistant nucleosome at the 3' end of the NFR. Transcriptome analysis after remodeller depletion reveals reciprocal mechanisms of transcriptional regulation by remodellers. Whereas at active genes individual remodellers have either positive or negative roles via altering nucleosome stability, at polycomb-enriched bivalent genes the same remodellers act in an opposite manner. These findings indicate that remodellers target specific nucleosomes at the edge of NFRs, where they regulate ES cell transcriptional programs.


Asunto(s)
Ensamble y Desensamble de Cromatina , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Genoma/genética , Células Madre Embrionarias de Ratones/metabolismo , Nucleosomas/genética , Nucleosomas/metabolismo , Animales , ADN Helicasas/metabolismo , Histonas/metabolismo , Ratones , Nucleasa Microcócica/metabolismo , Células Madre Embrionarias de Ratones/citología , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas/genética , ARN Polimerasa II/metabolismo , Especificidad por Sustrato , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Sitio de Iniciación de la Transcripción
4.
Molecules ; 27(2)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35056817

RESUMEN

Melatonin is a hormone secreted by the pineal gland that is involved in the biorhythm of reproductive activities. The present study investigated the inhibitory effects of melatonin on osteoclastogenesis in RAW 264.7 cells according to changes in V-ATPase and the corresponding inhibition of the MAPK and NFATc1 signaling processes. METHODS: the cytotoxic effect of melatonin was investigated by MTT assay. Osteoclast differentiation and gene expression of osteoclast-related factors were confirmed via TRAP staining, pit formation assay, immunofluorescence imaging, western blot, and real-time PCR. RESULTS: melatonin was found to inactivate the p38 and JNK of MAP kinase in RAW264.7 cells treated with RANKL and treated with a combination RANKL and melatonin for 1, 3, and 5 days. The melatonin treatment group showed a reduction in osteoclastogenesis transcription factors and ATP6v0d2 gene expression. CONCLUSIONS: melatonin inhibits osteoclast differentiation and cell fusion by inhibiting the expression of Atp6v0d2 through the inactivation of MAPK and NFATc1 signaling in RANKL-stimulated RAW264.7 macrophages. The findings of the present study suggest that melatonin could be a suitable therapy for bone loss and imply a potential role of melatonin in bone health.


Asunto(s)
Melatonina/farmacología , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas Quinasas Activadas por Mitógenos/antagonistas & inhibidores , Factores de Transcripción NFATC/antagonistas & inhibidores , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Osteoclastos/citología , Osteogénesis , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores , Animales , Antioxidantes/farmacología , Resorción Ósea/tratamiento farmacológico , Resorción Ósea/metabolismo , Resorción Ósea/patología , Diferenciación Celular , Células Cultivadas , Regulación hacia Abajo , Regulación de la Expresión Génica , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , FN-kappa B/antagonistas & inhibidores , Osteoclastos/efectos de los fármacos , Osteoclastos/metabolismo , Células RAW 264.7
5.
Medicina (Kaunas) ; 59(1)2022 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-36676666

RESUMEN

Background and Objectives: Natural products are necessary sources for drug discovery and have contributed to cancer chemotherapy over the past few decades. Furthermore, substances derived from plants have fewer side effects. Chrysophanol is an anthraquinone derivative that is isolated from rhubarb. Although the anticancer effect of chrysophanol on several cancer cells has been reported, studies on the antitumor effect of chrysophanol on oral squamous-cell carcinoma (OSCC) cells have yet to be elucidated. Therefore, in this study, we investigated the anticancer effect of chrysophanol on OSCC cells (CAL-27 and Ca9-22) via apoptosis and autophagy, among the cell death pathways. Results: It was found that chrysophanol inhibited the growth and viability of CAL-27 and Ca9-22 and induced apoptosis through the intrinsic pathway. It was also found that chrysophanol activates autophagy-related factors (ATG5, beclin-1, and P62/SQSTM1) and LC3B conversion. That is, chrysophanol activated both apoptosis and autophagy. Here, we focused on the roles of chrysophanol-induced apoptosis and the autophagy pathway. When the autophagy inhibitor 3-MA and PI3K/Akt inhibitor were used to inhibit the autophagy induced by chrysophanol, it was confirmed that the rate of apoptosis significantly increased. Therefore, we confirmed that chrysophanol induces apoptosis and autophagy at the same time, and the induced autophagy plays a role in interfering with apoptosis processes. Conclusions: Therefore, the potential of chrysophanol as an excellent anticancer agent in OSCC was confirmed via this study. Furthermore, the combined treatment of drugs that can inhibit chrysophanol-induced autophagy is expected to have a tremendous synergistic effect in overcoming oral cancer.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol 3-Quinasas/farmacología , Fosfatidilinositol 3-Quinasas/uso terapéutico , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/patología , Proteínas Proto-Oncogénicas c-akt , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas de Cabeza y Cuello , Apoptosis , Serina-Treonina Quinasas TOR/metabolismo , Serina-Treonina Quinasas TOR/uso terapéutico , Antraquinonas/farmacología , Antraquinonas/uso terapéutico , Autofagia , Línea Celular Tumoral , Proliferación Celular
6.
Genome Res ; 2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29444801

RESUMEN

Gene expression is controlled by a variety of proteins that interact with the genome. Their precise organization and mechanism of action at every promoter remains to be worked out. To better understand the physical interplay among genome-interacting proteins, we examined the temporal binding of a functionally diverse subset of these proteins: nucleosomes (H3), H2AZ (Htz1), SWR (Swr1), RSC (Rsc1, Rsc3, Rsc58, Rsc6, Rsc9, Sth1), SAGA (Spt3, Spt7, Ubp8, Sgf11), Hsf1, TFIID (Spt15/TBP and Taf1), TFIIB (Sua7), TFIIH (Ssl2), FACT (Spt16), Pol II (Rpb3), and Pol II carboxyl-terminal domain (CTD) phosphorylation at serines 2, 5, and 7. They were examined under normal and acute heat shock conditions, using the ultrahigh resolution genome-wide ChIP-exo assay in Saccharomyces cerevisiae Our findings reveal a precise positional organization of proteins bound at most genes, some of which rapidly reorganize within minutes of heat shock. This includes more precise positional transitions of Pol II CTD phosphorylation along the 5' ends of genes than previously seen. Reorganization upon heat shock includes colocalization of SAGA with promoter-bound Hsf1, a change in RSC subunit enrichment from gene bodies to promoters, and Pol II accumulation within promoter/+1 nucleosome regions. Most of these events are widespread and not necessarily coupled to changes in gene expression. Together, these findings reveal protein-genome interactions that are robustly reprogrammed in precise and uniform ways far beyond what is elicited by changes in gene expression.

7.
Medicina (Kaunas) ; 57(9)2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34577802

RESUMEN

Background and Objectives: Malignant glioblastoma (GBM) is caused by abnormal proliferation of glial cells, which are found in the brain. The therapeutic effects of surgical treatment, radiation therapy, and chemo-therapy against GBM are relatively poor compared with their effects against other tumors. Luteolin is abundant in peanut shells and is also found in herbs and other plants, such as thyme, green pepper, and celery. Luteolin is known to be effective against obesity and metabolic syndrome. The anti-inflammatory, and anti-cancer activities of luteolin have been investigated. Most studies have focused on the antioxidant and anti-inflammatory effects of luteolin, which is a natural flavonoid. However, the association between the induction of apoptosis by luteolin in GBM and autophagy has not yet been investigated. This study thus aimed to confirm the occurrence of luteolin-induced apoptosis and autophagy in GBM cells and to assess their relationship. Materials and Methods: A172 and U-373MG glioblastoma cell lines were used for this experiment. We confirmed the apoptosis effect of Luteolin on GBM cells using methods such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, immunofluorescence, Flow cytometry (FACS) western blot, and real-time quantitative PCR (qPCR). Results: In the luteolin-treated A172 and U-373MG cells, cell viability decreased in a concentration- and time-dependent manner. In addition, in A172 and U-373MG cells treated with luteolin at concentrations greater than 100 µM, nuclear fragmentation, which is a typical morphological change characterizing apoptosis, as well as fragmentation of caspase-3 and Poly (ADP-ribose) polymerase (PARP), which are apoptosis-related factors, were observed. Autophagy was induced after treatment with at least 50 µM luteolin. Inhibition of autophagy using 3MA allowed for a low concentration of luteolin to more effectively induce apoptosis in A172 and U-373MG cells. Conclusions: Results showed that luteolin induces apoptosis and autophagy and that the luteolin-induced autophagy promotes cell survival. Therefore, an appropriate combination therapy involving luteolin and an autophagy inhibitor is expected to improve the prognosis of GBM treatment.


Asunto(s)
Glioblastoma , Luteolina , Apoptosis , Autofagia , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Glioblastoma/tratamiento farmacológico , Humanos , Luteolina/farmacología , Luteolina/uso terapéutico
8.
Am J Physiol Lung Cell Mol Physiol ; 318(5): L1056-L1062, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32233789

RESUMEN

Air-liquid interface (ALI) cultures are ex vivo models that are used extensively to study the epithelium of patients with chronic respiratory diseases. However, the in vitro conditions impose a milieu different from that encountered in the patient in vivo, and the degree to which this alters gene expression remains unclear. In this study we employed RNA sequencing to compare the transcriptome of fresh brushings of nasal epithelial cells with that of ALI-cultured epithelial cells from the same patients. We observed a strong correlation between cells cultured at the ALI and cells obtained from the brushed nasal epithelia: 96% of expressed genes showed similar expression profiles, although there was greater similarity between the brushed samples. We observed that while the ALI model provides an excellent representation of the in vivo airway epithelial transcriptome for mechanistic studies, several pathways are affected by the change in milieu.


Asunto(s)
Mucosa Nasal/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/genética , Mucosa Respiratoria/metabolismo , Transcriptoma , Anciano , Aire , Fumar Cigarrillos/efectos adversos , Medios de Cultivo/química , Femenino , Perfilación de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Modelos Biológicos , Anotación de Secuencia Molecular , Mucosa Nasal/patología , Cultivo Primario de Células , Enfermedad Pulmonar Obstructiva Crónica/etiología , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/patología , Mucosa Respiratoria/patología , Análisis de Secuencia de ARN , Cornetes Nasales/metabolismo , Cornetes Nasales/patología
9.
Tob Control ; 29(Suppl 2): s80-s89, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31852817

RESUMEN

OBJECTIVE: We investigated the effects of chronic waterpipe (WP) smoke on pulmonary function and immune response in a murine model using a research-grade WP and the effects of acute exposure on the regulation of immediate-early genes (IEGs). METHODS: WP smoke was generated using three WP smoke puffing regimens based on the Beirut regimen. WP smoke samples generated under these puffing regimens were quantified for nicotine concentration. Mice were chronically exposed for 6 months followed by assessment of pulmonary function and airway inflammation. Transcriptomic analysis using RNAseq was conducted after acute exposure to characterise the IEG response. These biomarkers were then compared with those generated after exposure to dry smoke (without water added to the WP bowl). RESULTS: We determined that nicotine composition in WP smoke ranged from 0.4 to 2.5 mg per puffing session. The lung immune response was sensitive to the incremental severity of chronic exposure, with modest decreases in airway inflammatory cells and chemokine levels compared with air-exposed controls. Pulmonary function was unmodified by chronic WP exposure. Acute WP exposure was found to activate the immune response and identified known and novel IEG as potential biomarkers of WP exposure. CONCLUSION: Chronic exposure to WP smoke leads to immune suppression without significant changes to pulmonary function. Transcriptomic analysis of the lung after acute exposure to WP smoke showed activation of the immune response and revealed IEGs that are common to WP and dry smoke, as well as pools of IEGs unique to each exposure, identifying potential biomarkers specific to WP exposure.


Asunto(s)
Genes Inmediatos-Precoces , Pulmón/inmunología , Nicotina/análisis , Fumar en Pipa de Agua/inmunología , Animales , Biomarcadores/metabolismo , Femenino , Ratones , Ratones Endogámicos C57BL , Pipas de Agua
10.
J Cell Biochem ; 119(7): 5571-5580, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29380898

RESUMEN

With rapid economic growth and further developments in medical science, the entry into the aging population is currently increasing, as is the number of patients with metabolic diseases, such as hypertension, hyperlipidemia, heart disease, and diabetes. The current treatments for metabolic bone diseases, which are also on the rise, cause negative side effects. Bisphosphonates, which are used to treat osteoporosis, inhibit the bone resorption ability of osteoclasts and during prolonged administration, cause bisphosphonate-related osteonecrosis of the jaw (BRONJ). Numerous studies have shown the potential role of natural plant products as flavonoids in the protection against osteoporosis and in the influence of bone remodeling. Autophagy occurs after the degradation of cytoplasmic components within the lysosome and serves as an essential cytoprotective response to pathologic stress caused by certain diseases. In the present study, we hypothesized that the cytoprotective effects of flavonoids might be related to those associated with autophagy, an essential cytoprotective response to the pathologic stress caused by certain diseases, in osteoblasts. We demonstrated the cytoprotective effect of flavonoid-induced autophagy against the toxicity of zoledronate and the induction of autophagy by flavonoids to support osteogenic transcription factors, leading to osteoblast differentiation and bone formation. Further studies are necessary to clarify the connections between autophagy and osteogenesis. It would be helpful to shed light on methodological challenges through molecular biological studies and new animal models. The findings of the current study may help to delineate the potential role of flavonoids in the treatment of metabolic bone disease.


Asunto(s)
Autofagia/efectos de los fármacos , Conservadores de la Densidad Ósea/farmacología , Citoprotección/efectos de los fármacos , Difosfonatos/farmacología , Flavonoides/farmacología , Osteoblastos/efectos de los fármacos , Osteogénesis , Remodelación Ósea , Muerte Celular , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Osteoblastos/patología
11.
Nutr Cancer ; 70(1): 125-135, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29148840

RESUMEN

OSCC is the most common malignant cancer of the head and neck. EMT is an essential cellular process critical to the morphogenesis and homeostasis of solid tissues. It is also involved in the initial stage of cancer metastasis and invasion in which cells lose epithelial characteristics. While cancer therapy protocols such as surgery, radiation, and chemotherapy are effective and useful, the drug tolerance and toxicity of OSCC patients remain a problem. Resveratrol is mainly produced in red grape skin and exhibits anti-oxidative, anti-inflammatory, anti-proliferative, and anti-cancer properties. This study was undertaken to investigate the underlying mechanisms giving rise to the induction of apoptosis by resveratrol in the human tongue squamous cell carcinoma cell line. Resveratrol treatment resulted in a time- and dose-dependent decrease in cell viability and increased the apoptotic cell ratio in CAL-27, SCC15, and SCC25 cells. Resveratrol treatment of CAL-27 cells showed that several lines of apoptotic manifestation and decreased cell migration, invasion, and EMT-inducing transcription factor. Taken together, our findings demonstrate the inhibitory effect of resveratrol in human OSCC cells via the mitochondrial pathway and that resveratrol is able to inhibit cell invasion and migration by inhibiting the EMT-inducing transcription factors.


Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/tratamiento farmacológico , Transición Epitelial-Mesenquimal/efectos de los fármacos , Resveratrol/farmacología , Neoplasias de la Lengua/tratamiento farmacológico , Antineoplásicos Fitogénicos/farmacología , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Caspasas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Neoplasias de la Lengua/metabolismo , Neoplasias de la Lengua/patología
12.
Environ Toxicol ; 33(6): 640-649, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29451351

RESUMEN

Delphinidin is major anthocyanidin that is extracted from many pigmented fruits and vegetables. This substance has anti-oxidant, anti-inflammatory, anti-angiogenic, and anti-cancer properties. In addition, delphinidin strongly suppresses the migration and invasion of various cancer cells during tumorigenesis. Although delphinidin has anti-cancer effects, little is known about its functional roles in osteosarcoma (OS). For these reasons, we have demonstrated the effects of delphinidin on OS cell lines. The effects of delphinidin on cell viability and growth of OS cells were assessed using the MTT assay and colony formation assays. Hoechst staining indicated that the delphinidin-treated OS cells were undergoing apoptosis. Flow cytometry, confocal microscopy, and a western blot analysis also indicated evidence of apoptosis. Inhibition of cell migration and invasion was found to be associated with epithelial-to-mesenchymal transition (EMT), observed by using a wound healing assay, an invasion assay, and a western blot analysis. Furthermore, delphinidin treatment resulted in a profound reduction of phosphorylated forms of ERK and p38. These findings demonstrate that delphinidin treatment suppressed EMT through the mitogen-activated protein kinase (MAPK) signaling pathway in OS cell lines. Taken together, our results suggest that delphinidin strongly inhibits cell proliferation and induces apoptosis. Delphinidin treatment also suppresses cell migration and prevents EMT via the MAPK-signaling pathway in OS cell lines. For these reasons, delphinidin has anti-cancer effects and can suppress metastasis in OS cell lines, and it might be worth using as an OS therapeutic agent.


Asunto(s)
Antocianinas/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Óseas/patología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Osteosarcoma/patología , Neoplasias Óseas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Osteosarcoma/metabolismo , Fosforilación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/efectos de los fármacos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
13.
Int J Mol Sci ; 19(1)2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-29301320

RESUMEN

Kaempferol, a flavonoid compound, is derived from the rhizome of Kaempferia galanga L., which is used in traditional medicine in Asia. Autophagy has pleiotropic functions that are involved in cell growth, survival, nutrient supply under starvation, defense against pathogens, and antigen presentation. There are many studies dealing with the inhibitory effects of natural flavonoids in bone resorption. However, no studies have explained the relationship between the autophagic and inhibitory processes of osteoclastogenesis by natural flavonoids. The present study was undertaken to investigate the inhibitory effects of osteoclastogenesis through the autophagy inhibition process stimulated by kaempferol in murin macrophage (RAW 264.7) cells. The cytotoxic effect of Kaempferol was investigated by MTT assay. The osteoclast differentiation and autophagic process were confirmed via tartrate-resistant acid phosphatase (TRAP) staining, pit formation assay, western blot, and real-time PCR. Kaempferol controlled the expression of autophagy-related factors and in particular, it strongly inhibited the expression of p62/SQSTM1. In the western blot and real time-PCR analysis, when autophagy was suppressed with the application of 3-Methyladenine (3-MA) only, osteoclast and apoptosis related factors were not significantly affected. However, we found that after cells were treated with kaempferol, these factors inhibited autophagy and activated apoptosis. Therefore, we presume that kaempferol-inhibited autophagy activated apoptosis by degradation of p62/SQSTM1. Further study of the p62/SQSTM1 gene as a target in the autophagy mechanism, may help to delineate the potential role of kaempferol in the treatment of bone metabolism disorders.


Asunto(s)
Autofagia/efectos de los fármacos , Quempferoles/farmacología , Osteoclastos/citología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Autofagia/genética , Resorción Ósea/patología , Diferenciación Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Osteogénesis/genética , Proteolisis/efectos de los fármacos , Ligando RANK/farmacología , Células RAW 264.7 , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteína Sequestosoma-1/metabolismo
14.
Lasers Med Sci ; 32(3): 533-541, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28091848

RESUMEN

Melatonin has anabolic effects on the bone, even under hypoxia, and laser irradiation has been shown to improve osteoblastic differentiation. The aim of this study was to investigate whether laser irradiation and melatonin would have synergistic effects on osteoblastic differentiation and mineralization under hypoxic conditions. MC3T3-E1 cells were exposed to 1% oxygen tension for the hypoxia condition. The cells were divided into four groups: G1-osteoblast differentiation medium only (as the hypoxic condition), G2-treatment with 50 µM melatonin only, G3-laser irradiation (808 nm, 80 mW, GaAlAs diode) only, and G4-treatment with 50 µM melatonin and laser irradiation (808 nm, 80 mW, GaAlAs diode). Immunoblotting showed that osterix expression was markedly increased in the melatonin-treated and laser-irradiated cells at 48 and 72 h. In addition, alkaline phosphatase activity significantly increased and continued to rise throughout the experiment. Alizarin Red staining showed markedly increased mineralized nodules as compared with only melatonin-treated or laser-irradiated cells at day 7, which significantly increased by day 14. Moreover, when melatonin-treated cells were laser-irradiated, the differentiation and mineralization of cells were found to involve p38 MAPK and PRKD1 signaling mechanisms. However, the enhanced effects of laser irradiation with melatonin were markedly inhibited when the cells were treated with luzindole, a selective melatonin receptor antagonist. Therefore, we concluded that laser irradiation could promote the effect of melatonin on the differentiation and mineralization of MC3T3-E1 cells under hypoxic conditions, and that this process is mediated through melatonin 1/2 receptors and PKRD/p38 signaling pathways.


Asunto(s)
Regeneración Ósea/fisiología , Hipoxia/fisiopatología , Láseres de Semiconductores/uso terapéutico , Terapia por Luz de Baja Intensidad/métodos , Melatonina/uso terapéutico , Osteoblastos/fisiología , Fosfatasa Alcalina/metabolismo , Animales , Regeneración Ósea/efectos de los fármacos , Regeneración Ósea/efectos de la radiación , Diferenciación Celular/efectos de la radiación , Terapia Combinada , Ratones , Osteoblastos/efectos de los fármacos , Osteoblastos/efectos de la radiación , Osteogénesis/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
15.
Environ Toxicol ; 32(11): 2371-2378, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28722333

RESUMEN

Embelin is an active ingredient of traditional herbal remedies for cancer and other diseases. Recently, it has been suggested that autophagy may play an important role in cancer therapy. However, little data are available regarding the role of autophagy in oral cancers. Therefore, we conducted this study to examine whether Embelin modulates autophagy in Ca9-22. Our results showed that Embelin had anticancer activity against the Ca9-22 human tongue squamous cell, and we observed that autophagic vacuoles were formed by MDC and AO. We also analyzed Embelin-treated Ca9-22 cells for the presence of biochemical markers and found that it directly affected the conversion of LC3-II, the degradation of p62/SQSTM1, full-length cleavage formation of ATG5-ATG12 complex and Beline-1, and caspase activation. Rescue experiments using an autophagy inhibitor showed Embelin-induced cell death in Ca9-22, confirming that autophagy acts as a pro-death signal. Furthermore, Embelin exhibited anticancer activity against Ca9-22 via both autophagy and apoptosis. These findings suggest that Embelin may potentially contribute to oral cancer treatment and provide useful information for the development of a new therapeutic agent.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Benzoquinonas/farmacología , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de la Lengua/tratamiento farmacológico , Proteína Inhibidora de la Apoptosis Ligada a X/antagonistas & inhibidores , Línea Celular Tumoral , Humanos , Fagosomas/ultraestructura
16.
BMC Complement Altern Med ; 16(1): 333, 2016 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-27581091

RESUMEN

BACKGROUND: Kaempferol, a kind of flavonol, has been reported to possess various osteogenic biological activities, such as inhibiting bone resorption of osteoclasts and promoting the differentiation and mineralization of preosteoblasts. However, the precise cellular mechanism of action of kaempferol in osteogenesis is elusive. Autophagy is a major intracellular degradation system, which plays an important role in cell growth, survival, differentiation and homeostasis in mammals. Recent studies showed that autophagy appeared to be involved in the degradation of osteoclasts, osteoblasts and osteocytes, potentially pointing to a new pathogenic mechanism of bone homeostasis and bone marrow disease. The potential correlation between autophagy, osteogenesis and flavonoids is unclear. METHODS: The present study verified that kaempferol promoted osteogenic differentiation and mineralization and that it elevated osteogenic gene expression based on alkaline phosphatase (ALP) activity, alizarin red staining and quantitative PCR. And then we found that kaempferol induced autophagy by acridine orange (AO) and monodansylcadaverine (MDC) staining and autophagy-related protein expression. The correlation between kaempferol-induced autophagy and the osteogenic process was confirmed by the autophagy inhibitor 3-methyladenine (3-MA). RESULTS: Kaempferol promoted the proliferation, differentiation and mineralization of osteoblasts at a concentration of 10 µM. Kaempferol showed cytotoxic properties at concentrations above 50 µM. Concentrations above 10 µM decreased ALP activity, whereas those up to 10 µM increased ALP activity. Kaempferol at concentrations up to 10 µM also increased the expression of the osteoblast- activated factors RUNX-2, osterix, BMP-2 and collagen I according to RT-PCR analyses. 10 µM or less, the higher of the concentration and over time, kaempferol promoted the activity of osteoblasts. Kaempferol induced autophagy. It also increased the expression of the autophagy-related factors beclin-1, SQSTM1/p62 and the conversion of LC3-II from LC3-I. The application of 3-MA decreased the activity of ALP and the autophagy induced by kaempferol. In the RT-PCR analysis, the expression of RUNX-2, osterix, BMP-2 and collagen I was decreased. CONCLUSION: The present study showed that kaempferol stimulated the osteogenic differentiation of cultured osteoblasts by inducing autophagy.


Asunto(s)
Autofagia/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Flavonoides/farmacología , Quempferoles/farmacología , Adenina/análogos & derivados , Adenina/farmacología , Animales , Línea Celular , Ratones , Osteogénesis/efectos de los fármacos
17.
Nat Genet ; 39(4): 561-5, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17353894

RESUMEN

Rapid translation of genome sequences into meaningful biological information hinges on the integration of multiple experimental and informatics methods into a cohesive platform. Despite the explosion in the number of genome sequences available, such a platform does not exist for filamentous fungi. Here we present the development and application of a functional genomics and informatics platform for a model plant pathogenic fungus, Magnaporthe oryzae. In total, we produced 21,070 mutants through large-scale insertional mutagenesis using Agrobacterium tumefaciens-mediated transformation. We used a high-throughput phenotype screening pipeline to detect disruption of seven phenotypes encompassing the fungal life cycle and identified the mutated gene and the nature of mutation for each mutant. Comparative analysis of phenotypes and genotypes of the mutants uncovered 202 new pathogenicity loci. Our findings demonstrate the effectiveness of our platform and provide new insights on the molecular basis of fungal pathogenesis. Our approach promises comprehensive functional genomics in filamentous fungi and beyond.


Asunto(s)
Genoma Fúngico , Magnaporthe/genética , Factores de Virulencia/genética , Factores de Virulencia/fisiología , Agrobacterium tumefaciens/genética , Mapeo Cromosómico , Cromosomas Fúngicos , Genes Fúngicos/fisiología , Genotipo , Modelos Biológicos , Organismos Modificados Genéticamente , Fenotipo , Factores de Virulencia/aislamiento & purificación
18.
Int J Med Sci ; 12(7): 583-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26283875

RESUMEN

BACKGROUND: Ischemia-reperfusion of bone occurs in a variety of clinical conditions, such as orthopedic arthroplasty, plastic gnathoplasty, spinal surgery, and amputation. Usually, cellular models of hypoxia-reoxygenation reflect in vivo models of ischemia-reperfusion. With respect to hypoxia-reoxygenation conditions, the effects of remifentanil on osteogenesis have received little attention. Therefore, we investigated the effects of remifentanil on the proliferation and differentiation of osteoblasts during hypoxic-reoxygenation. METHODS: After remifentanil (0.1, 1 ng/mL) preconditioning for 2 hours, human osteoblasts were cultured under 1% oxygen tension for 24 hours. Thereafter, the cells were reoxygenated for 12 hours at 37 °C. The naloxone groups were treated with naloxone for 30 minutes before remifentanil treatment. We measured cell viability via MTT assay. Osteoblast maturation was determined by assay of bone nodular mineralization. Quantitative PCR and western blot methods were used to determine BMP-2, osteocalcin, Akt, type I collagen, osterix, TGF-ß1, HIF-1α, and RUNX2 expression levels. RESULTS: Osteoblast viability and bone nodular mineralization by osteoblasts is recovered by remifentanil preconditioning from hypoxia-reoxygenation insult. During hypoxic-reoxygenation condition, remifentanil preconditioning induced the expression of BMP-2, osteocalcin, Akt, type I collagen, osterix, TGF-ß1, HIF-1α, and RUNX2 in osteoblasts. CONCLUSIONS: Under hypoxia-reoxygenation conditions, remifentanil preconditioning enhanced the cell viability and maturation of osteoblasts, and stimulated the expression of proteins associated with osteoblast proliferation and differentiation of the osteoblast. Our results suggest that remifentanil may help in the treatment of bone stress injuries.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Piperidinas/administración & dosificación , Daño por Reperfusión/tratamiento farmacológico , Huesos/efectos de los fármacos , Huesos/lesiones , Hipoxia de la Célula/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Naloxona/administración & dosificación , Osteogénesis/efectos de los fármacos , Oxígeno/metabolismo , Remifentanilo , Daño por Reperfusión/genética , Daño por Reperfusión/patología
19.
Lasers Med Sci ; 30(2): 635-43, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23835780

RESUMEN

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a side effect of bisphosphonate therapy. However, its pathophysiology is not yet fully elucidated, and effective treatment of BRONJ remains unclear. The aim of this study is to investigate the effects of alendronate on oral keratinocytes and of low-level laser therapy (LLLT) on alendronate-treated keratinocytes, specifically by evaluating their viability, apoptosis, and wound healing function after irradiation. Oral keratinocyte cells (HaCaT) were exposed to 25 µM alendronate. Then, laser irradiation was performed with a low-level Ga-Al-As laser (λ = 808 ± 3 nm, 80 mW, and 80 mA; NDLux, Seoul, Korea) using 1.2 J/cm(2) energy dose. Viability was analyzed using MTT assay. Apoptosis was measured by Hoechst staining, caspase assay. Changes in secretion of IL-8, VEGF, and collagen type I were studied by ELISA and immunofluorescence microscopy. Scratch wound assays were also performed to measure cellular migration. Our results show that alendronate inhibits keratinocyte viability, expression of IL-8, VEGF, and collagen type I which are intimately related to healing events and cell migration while promoting apoptosis. Our results serve to demonstrate the utility of LLLT in partially overcoming the inhibitory effects of this bisphosphonate. From these results, the authors believe that the present study will provide an experimental basis for a fuller explanation of the clinical effects of LLLT as a BRONJ treatment modality.


Asunto(s)
Difosfonatos/química , Queratinocitos/efectos de los fármacos , Terapia por Luz de Baja Intensidad/métodos , Cicatrización de Heridas/efectos de los fármacos , Alendronato/química , Apoptosis/efectos de los fármacos , Osteonecrosis de los Maxilares Asociada a Difosfonatos/cirugía , Línea Celular Tumoral , Movimiento Celular , Supervivencia Celular , Colágeno Tipo I/metabolismo , Humanos , Interleucina-8/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
20.
Am J Kidney Dis ; 63(4): 584-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24315769

RESUMEN

BACKGROUND: Serum total and low-density lipoprotein (LDL) cholesterol levels are elevated in patients with nephrotic syndrome and those with kidney failure treated by peritoneal dialysis (PD), who are characterized by heavy losses of protein in urine and peritoneal dialysate, respectively. Hypercholesterolemia in nephrotic syndrome is associated with and largely due to acquired LDL receptor (LDLR) deficiency. Because PCSK9 (proprotein convertase subtilisin/kexin type 9) promotes degradation of LDLR, we tested the hypothesis that elevation of LDL cholesterol levels in patients with nephrotic syndrome and PD patients may be due to increased PCSK9 levels. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: Patients with nephrotic syndrome or treated by PD or hemodialysis and age- and sex-matched healthy Korean individuals (n=15 in each group). PREDICTOR: Group and serum total and LDL cholesterol levels. OUTCOMES: Plasma PCSK9 concentration. MEASUREMENTS: Concentrations of fasting serum PCSK9, lipids, and albumin, and urine protein excretion. RESULTS: Mean serum total and LDL cholesterol levels in patients with nephrotic syndrome (317.9±104.2 [SD] and 205.9±91.1mg/dL) and PD patients (200.0±27.6 and 126.7±18.5mg/dL) were significantly (P<0.05) higher than in hemodialysis patients (140.9±22.9 and 79.1±19.5mg/dL) and the control group (166.5±26.5 and 95.9±25.2mg/dL). This was associated with significantly (P<0.05) higher plasma PCSK9 levels in patients with nephrotic syndrome (15.13±4.99ng/mL) and PD patients (13.30±1.40ng/mL) than in the control (9.19±0.60ng/mL) and hemodialysis (7.30±0.50ng/mL) groups. Plasma PCSK9 level was directly related to total and LDL cholesterol concentrations in the study population (r=0.559 [P<0.001] and r=0.497 [P<0.001], respectively). LIMITATIONS: Small number of participants may limit generalizability. CONCLUSIONS: Nephrotic syndrome and PD are associated with higher plasma PCSK9 concentration, which can contribute to elevation of LDL levels by promoting LDLR deficiency.


Asunto(s)
Apoptosis/fisiología , LDL-Colesterol/sangre , Síndrome Nefrótico/sangre , Diálisis Peritoneal , Proproteína Convertasas/sangre , Serina Endopeptidasas/sangre , Adulto , Colesterol/sangre , Comorbilidad , Estudios Transversales , Femenino , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/epidemiología , Hipercolesterolemia/prevención & control , Masculino , Persona de Mediana Edad , Síndrome Nefrótico/epidemiología , Síndrome Nefrótico/terapia , Proproteína Convertasa 9 , Diálisis Renal , Adulto Joven
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