RESUMO
Mutations in the lamin A/C gene (LMNA) cause laminopathies such as the premature aging Hutchinson Gilford progeria syndrome (HGPS) and altered lamin A/C levels are found in diverse malignancies. The underlying lamin-associated mechanisms remain poorly understood. Here we report that lamin A/C-null mouse embryo fibroblasts (Lmna-/- MEFs) and human progerin-expressing HGPS fibroblasts both display reduced NAD+ levels, unstable mitochondrial DNA and attenuated bioenergetics. This mitochondrial dysfunction is associated with reduced chromatin recruitment (Lmna-/- MEFs) or low levels (HGPS) of PGC1α, the key transcription factor for mitochondrial homeostasis. Lmna-/- MEFs showed reduced expression of the NAD+-biosynthesis enzyme NAMPT and attenuated activity of the NAD+-dependent deacetylase SIRT1. We find high PARylation in lamin A/C-aberrant cells, further decreasing the NAD+ pool and consistent with impaired DNA base excision repair in both cell models, a condition that fuels DNA damage-induced PARylation under oxidative stress. Further, ATAC-sequencing revealed a substantially altered chromatin landscape in Lmna-/- MEFs, including aberrantly reduced accessibility at the Nampt gene promoter. Thus, we identified a new role of lamin A/C as a key modulator of mitochondrial function through impairments of PGC1α and the NAMPT-NAD+ pathway, with broader implications for the aging process.
Assuntos
Lamina Tipo A/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Progéria , Animais , Cromatina/metabolismo , DNA Mitocondrial/metabolismo , Fibroblastos/metabolismo , Humanos , Lamina Tipo A/genética , Camundongos , Mitocôndrias/metabolismo , NAD/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Progéria/metabolismo , Sirtuína 1/genéticaRESUMO
The brain is rich in long-chain PUFA, which play an essential role in its development and functions. Here, we examined the impact of maternal n-3 PUFA intake deficiency during gestation and lactation on the development of glial cells in the pup's developing cerebral cortex. In addition, using myelination as indicator and the anti-myelin basic protein as measurement to establish the relationship between the number of glial fibrillary acidic protein (GFAP)-positive cells and the development of oligodendrocytes, we determined the myelination state of the somatosensory cortex at postnatal day 14. Rat dams were fed either a control (Cont) or an n-3 PUFA-deficient (Def) diet for 60 d (acclimatisation: 14 d; gestation: 21 d; and lactation: 21 d). Pups lactated from dams throughout the experiment. The distribution pattern of astrocytes in pups on postnatal day 7 was immunohistochemically analysed using GFAP and brain lipid binding protein (BLBP) as markers for mature astrocytes and astrocyte-specific radial glial cells, respectively. It was observed that, when compared with Cont pups, GFAP-positive cells decreased, BLBP-positive cells increased and myelinated structures were sparser in the somatosensory cortices of Def pups. In the open field test on postnatal day 21, behavioural parameters did not differ between groups. Our results indicated that inhibited maturation of astrocytes caused by maternal n-3 PUFA deficiency hindered the development of brain glial cells of neonatal rats; hence, maternal n-3 PUFA intake during the gestation and lactation periods may have been crucial for the brain cell composition of pups.
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Astrócitos , Ácidos Graxos Ômega-3 , Animais , Feminino , Ratos , Animais Recém-Nascidos , Encéfalo , Ácidos Graxos Ômega-3/metabolismo , Lactação , NeurogliaRESUMO
Because cyanobacteriochrome photoreceptors need only a single compact domain for chromophore incorporation and for absorption of visible spectra including the long-wavelength far-red region, these molecules have been paid much attention for application to bioimaging and optogenetics. Most cyanobacteriochromes, however, have a drawback to incorporate phycocyanobilin that is not available in the mammalian cells. In this study, we focused on biliverdin (BV) that is a mammalian intrinsic chromophore and absorbs the far-red region and revealed that replacement of only four residues was enough for conversion from BV-rejective cyanobacteriochromes into BV-acceptable molecules. We succeeded in determining the crystal structure of one of such engineered molecules, AnPixJg2_BV4, at 1.6 Å resolution. This structure identified unusual covalent bond linkage, which resulted in deep BV insertion into the protein pocket. The four mutated residues contributed to reducing steric hindrances derived from the deeper insertion. We introduced these residues into other domains, and one of them, NpF2164g5_BV4, produced bright near-infrared fluorescence from mammalian liver in vivo. Collectively, this study provides not only molecular basis to incorporate BV by the cyanobacteriochromes but also rational strategy to open the door for application of cyanobacteriochromes to visualization and regulation of deep mammalian tissues.
Assuntos
Biliverdina , Fotorreceptores Microbianos , Engenharia de Proteínas/métodos , Animais , Biliverdina/química , Biliverdina/metabolismo , Células COS , Chlorocebus aethiops , Cianobactérias/genética , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Fígado/química , Fígado/diagnóstico por imagem , Fígado/metabolismo , Camundongos , Modelos Moleculares , Imagem Óptica , Fotorreceptores Microbianos/química , Fotorreceptores Microbianos/genética , Fotorreceptores Microbianos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , TransfecçãoRESUMO
The eukaryotic nucleus is not a homogenous single-spaced but a highly compartmentalized organelle, partitioned by various types of membraneless structures, including nucleoli, PML bodies, paraspeckles, DNA damage foci and RNA clouds. Over the past few decades, these nuclear structures have been implicated in biological reactions such as gene regulation and DNA damage response and repair, and are thought to provide "microenvironments," facilitating these reactions in the nucleus. Notably, an altered morphology of these nuclear structures is found in many cancers, which may relate to so-called "nuclear atypia" in histological examinations. While the diagnostic significance of nuclear atypia has been established, its nature has remained largely enigmatic and awaits characterization. Here, we review the emerging biophysical principles that govern biomolecular condensate assembly in the nucleus, namely, liquid-liquid phase separation (LLPS), to investigate the nature of the nuclear microenvironment. In the nucleus, LLPS is typically driven by multivalent interactions between proteins with intrinsically disordered regions, and is also facilitated by protein interaction with nucleic acids, including nuclear non-coding RNAs. Importantly, an altered LLPS leads to dysregulation of nuclear events and epigenetics, and often to tumorigenesis and tumor progression. We further note the possibility that LLPS could represent a new therapeutic target for cancer intervention.
Assuntos
Núcleo Celular/metabolismo , Suscetibilidade a Doenças , Neoplasias/etiologia , Neoplasias/metabolismo , Biomarcadores , Núcleo Celular/genética , Cromatina/genética , Cromatina/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Extração Líquido-Líquido , Mitose , Neoplasias/patologia , Proteômica/métodos , RNA não TraduzidoRESUMO
BACKGROUND: Oral squamous cell carcinoma (OSCC) has increased morbidity, and its high metastatic potential affects patient survival. Bromodomain containing 4 (BRD4) is a chromatin protein that associates with acetylated histone lysines and facilitates transcription. BRD4 has been implicated in cell proliferation, metastasis, and prognosis in several types of cancer. However, the role of BRD4 in OSCC remains to be elucidated. METHODS: We investigated the role of BRD4 and its potential utility as a therapeutic target in OSCC. RESULTS: JQ1, the BRD4 inhibitor, suppressed the cell proliferation, migration, and invasion in the OSCC cell lines and in vivo. JQ1 reduced the expression levels of 15 metastasis genes in OSCC, including matrix metallopeptidase 2 (MMP2). Our chromatin immunoprecipitation assay showed that JQ1 reduced the BRD4 binding to the histone H3 lysine 27 acetylation-enriched sites in the MMP2 locus. Analyses of biopsy specimens from OSCC patients revealed that the BRD4 and MMP2 expression levels were correlated in the cancerous regions, and both were highly expressed in lymph node metastasis cases, including delayed metastasis. CONCLUSIONS: BRD4 contributes to metastasis in OSCC, through the epigenetic regulation of the MMP2 gene, and thus BRD4 may represent a therapeutic target and a novel prediction indicator for metastasis.
Assuntos
Carcinoma de Células Escamosas/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Metástase Linfática/genética , Metaloproteinase 2 da Matriz/genética , Neoplasias Bucais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Azepinas/farmacologia , Carcinoma de Células Escamosas/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histonas/metabolismo , Humanos , Masculino , Camundongos , Neoplasias Bucais/metabolismo , Prognóstico , Fatores de Transcrição/antagonistas & inibidores , Triazóis/farmacologiaRESUMO
MicroRNAs are a class of small, endogenous, noncoding 18- to 24-nucleotide-long RNAs that can regulate multiple processes related to cancer progression. However, their clinical value in patients with oral squamous cell carcinoma has not yet been fully explored. Therefore, the aim of this study was to investigate the clinical significance of circulating microRNAs in oral squamous cell carcinoma patients. The expression levels of circulating miR-1246 and miR-1290 in healthy volunteers and oral squamous cell carcinoma patients were examined by quantitative real-time polymerase chain reaction. The expression levels of both microRNAs in the radioresistant oral squamous cell carcinoma cell line (SAS-R) and the parent cell line (SAS) and in the conditioned medium obtained from these cell lines were also examined by quantitative real-time polymerase chain reaction. In addition, the correlations between circulating microRNA status and various clinicopathological features in 55 oral squamous cell carcinoma patients with locally advanced oral squamous cell carcinoma who underwent surgery following 5-fluorouracil-based chemoradiotherapy were examined. The expression level of miR-1290 was significantly lower in the plasma of oral squamous cell carcinoma patients than in that of healthy volunteers (p < 0.01). The expression levels of microRNAs in the conditioned medium and in the cells varied from cell to cell. In the clinicopathological analyses, the frequency of patients with low miR-1290 levels was significantly higher among cases with lower pathological differentiation and among those with a poor pathological response for preoperative chemoradiotherapy (p = 0.030 each). Furthermore, Cox regression analysis based on the 5-year overall survival and disease-free survival revealed that miR-1290 status was a significant prognostic factor for patients with oral squamous cell carcinoma (hazard ratio = 0.169, p = 0.008, and hazard ratio = 0.186, p = 0.008, respectively). Circulating miR-1290 status could be a valuable biomarker for predicting the clinical response to chemoradiotherapy as well as overall survival in patients with oral squamous cell carcinoma.
Assuntos
Biomarcadores Tumorais/sangue , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/terapia , MicroRNAs/sangue , Neoplasias Bucais/sangue , Neoplasias Bucais/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quimiorradioterapia/métodos , Intervalo Livre de Doença , Feminino , Fluoruracila/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Prognóstico , Estudos RetrospectivosRESUMO
The highly malignant phenotype of oral squamous cell carcinoma (OSCC), including the presence of nodal and distant metastasis, reduces patient survival. High-mobility group A protein 2 (HMGA2) is a non-histone chromatin factor that is involved in advanced malignant phenotypes and poor prognosis in several human cancers. However, its biological role in OSCC remains to be elucidated. The purpose of this study was to determine the clinical significance and role of HMGA2 in the malignant potential of OSCC. We first investigated the expression pattern of HMGA2 and its clinical relevance in 110 OSCC specimens using immunohistochemical staining. In addition, we examined the effects HMGA2 on the regulation of vascular endothelial growth factor (VEGF)-A, VEGF-C, and fibroblast growth factor (FGF)-2, which are related to angiogenesis, in vitro. High expression of HMGA2 was significantly correlated with distant metastasis and poor prognosis. Further, HMGA2 depletion in OSCC cells reduced the expression of angiogenesis genes. In OSCC tissues with high HMGA2 expression, angiogenesis genes were increased and a high proportion of blood vessels was observed. These findings suggest that HMGA2 plays a significant role in the regulation of angiogenesis and might be a potential biomarker to predict distant metastasis and prognosis in OSCC.
Assuntos
Carcinoma de Células Escamosas/metabolismo , Proteína HMGA2/metabolismo , Neoplasias Bucais/metabolismo , Neovascularização Patológica/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Feminino , Proteína HMGA2/análise , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/irrigação sanguínea , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/patologia , Invasividade Neoplásica/patologia , Neovascularização Patológica/diagnóstico , Neovascularização Patológica/patologia , PrognósticoRESUMO
[Purpose] This study involved performing longitudinal measurements of muscle mass in elderly patients with mild disequilibrium using a body composition meter. The rate of change and characteristics were determined according to the level of care needed. [Participants and Methods] Bioelectrical impedance was used to measure body composition in 20 elderly females in Care Needs Category 1 (n=10) and 2 (n=8); body composition was measured every 3 months for 1â year. [Results] Compared to Category 1, the muscle mass at each body site was lower in Category 2 and the muscle mass of the whole body and thighs in Category 2 decreased throughout the year. [Conclusion] Muscle mass in elderly patients needing assistance depended on the level of care, as suggested by the decrease in muscle mass in the whole body and thighs in Category 2 over time. In addition, effective rehabilitation intervention for the trunk is important.
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Colonic hydrogen (H2) can suppress oxidative stress and damage in the body. We examined the minimum requirement of high amylose cornstarch (HAS) to maintain high colonic H2 production for 24 h. Ileorectostomized and sham-operated rats were fed a control diet supplemented with or without 20% HAS for 7 days. Colonic starch utilization was determined. Next, rats were fed the control diet with or without 10% or 20% HAS for 14 or 28 days, respectively. Breath and flatus H2 excretion for 24 h was measured. 1.04 g of resistant fraction in HAS was utilized for 24 h by colonic bacteria. High H2 excretion was not maintained for 24 h in rats fed the 10% HAS diet, from which only 0.89 g of resistant starch was estimated to be delivered. High colonic H2 production for 24 h would be maintained by delivering more HAS to the large intestine than is utilized.
Assuntos
Amilose/química , Colo/efeitos dos fármacos , Colo/metabolismo , Hidrogênio/metabolismo , Amido/química , Amido/farmacologia , Animais , Dieta , Digestão , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Amido/metabolismo , Fatores de TempoRESUMO
Colonic hydrogen (H2) protects against inflammation-induced oxidative stress. We examined the effect of a new highly branched α-glucan, isomaltodextrin (IMD), on colonic H2 production in rats. Rats were fed a 16.7% IMD, 8.8% indigestible dextrin (ID), or 10.4% high amylose cornstarch diet (Expt. 1), were fed diets containing 3.3-16.7% IMD (Expt. 2), or were fed diets containing 16.7% IMD or 5.2% fructooligosaccharide (FOS) (Expt. 3), for 14 days. Compared with the control group, feeding IMD or other α-glucans dose dependently and significantly increased H2 excretion and portal H2 concentration. The ability of IMD to increase H2 production was not inferior to that of FOS. The cecal Firmicutes/Bacteroidetes ratio in the IMD group was 5-14% of that in the control group. The cecal abundance of bifidobacteria was significantly greater in the IMD group than in the control group. Taken together, IMD, as well as other α-glucans, significantly increased colonic H2 production in a dose-dependent manner.
Assuntos
Colo/efeitos dos fármacos , Dextrinas/metabolismo , Polissacarídeos/farmacologia , Animais , Colo/metabolismo , Hidrogênio , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Small intestinal epithelium is a self-renewing system in which the entire sequence of cell proliferation, differentiation, and removal is coupled to cell migration along the crypt-villus axis. We examined whether dual labeling with different thymidine analogues, 5-bromo-2'-deoxyuridine (BrdU) and 5-ethynyl-2'-deoxyuridine (EdU), can be used to estimate cell migration rates on the villi of small intestines in rats. Rats received a single intraperitoneal injection of BrdU and EdU within a time interval, and signals in tissue sections were examined by immunohistochemistry and the "click" reaction, respectively. We successfully observed BrdU- and EdU-positive cells on the epithelium with no cross-reaction. In addition, we observed an almost complete overlapping of BrdU- and EdU-positive cells in rats administered simultaneously with BrdU and EdU. By calculating the cell migration rate by dividing the distance between the median cell positions of the distribution of BrdU- and EdU-positive cells by the time between the injection of BrdU and EdU, we estimated approximately 9 and 5 µm/h for the cell migration rates on the villi in the jejunum and ileum, respectively. We propose that dual labeling with BrdU and EdU within a time interval, followed by detecting with immunohistochemistry and the click reaction, respectively, is useful to estimate accurately the cell migration rate in the intestinal epithelium in a single animal.
Assuntos
Bromodesoxiuridina/farmacologia , Movimento Celular/fisiologia , Desoxiuridina/análogos & derivados , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Coloração e Rotulagem/métodos , Animais , Desoxiuridina/farmacologia , Mucosa Intestinal/citologia , Intestino Delgado/citologia , Masculino , Ratos , Ratos WistarRESUMO
Spock3/Testican-3 is a nervous system-expressed heparan sulfate proteoglycan belonging to a subgroup of the BM-40/SPARC/osteonectin family, the role of which in brain development is unclear. Because Spock1, a member of the Spock family, inhibits their attachment to substrates and the neurite outgrowth of cultured neuronal cells, Spock3 is also thought to be similarly involved in the neuronal development. In the present study, we established a Spock3-mutant mouse harboring a deletion extending from the presumptive upstream regulatory region to exon 4 of the Spock3 locus and performed histological and behavioral studies on these mutant mice. In wild-type (WT) mice, all Spock members were clearly expressed during brain development. In adults, intense Spock1 and Spock2 expressions were observed throughout the entire brain; whereas, Spock3 expression was no longer visible except in the thalamic nuclei. Thus, Spock3 expression is mostly confined to the developmental stage of the brain. In adult mutant mice, the cells of all cortical layers were swollen. The corpus callosum was narrowed around the central region along the rostral-caudal axis and many small spaces were observed without myelin sheaths throughout the entire corpus callosum. In addition, the cortical input and output fibers did not form into thick bundled fibers as well as the WT counterparts did. Moreover, a subpopulation of corticospinal axonal fibers penetrated into the dorsal striatum with moderately altered orientations. Consistent with these modifications of brain structures, the mutant mice exhibited decreased anxiety-like behavior and lowered sociability. Together, these results demonstrate that Spock3 plays an important role in the formation or maintenance of major neuronal structures in the brain.
Assuntos
Agenesia do Corpo Caloso/genética , Ansiedade/genética , Axônios/metabolismo , Comportamento Animal/fisiologia , Corpo Caloso/metabolismo , Proteoglicanas/genética , Comportamento Social , Agenesia do Corpo Caloso/metabolismo , Agenesia do Corpo Caloso/patologia , Animais , Ansiedade/metabolismo , Ansiedade/patologia , Axônios/patologia , Corpo Caloso/patologia , Masculino , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Proteoglicanas/metabolismoRESUMO
Background: Voriconazole is an antifungal drug for which therapeutic monitoring is recommended to prevent side effects. Temporary administration of the antiemetic drug fosaprepitant remarkably decreases the plasma concentration of voriconazole from the therapeutic range. The ratio of the major metabolite voriconazole N-oxide to voriconazole exceeded that at any other time for a patient who started chemotherapy during voriconazole therapy. We attributed this unpredictable result to cytochrome P450 3A4 induced by aprepitant that was converted from fosaprepitant in vivo. Methods: Concentrations of voriconazole and voriconazole N-oxide were measured using liquid chromatography-mass spectrometry/mass spectrometry in primary human hepatocytes after incubation with aprepitant. Aprepitant suppressed voriconazole N-oxide formation within 24 h, followed by a continuous increase. Levels of drug-metabolizing cytochrome P450 mRNA were measured using real-time PCR in primary human hepatocytes incubated with aprepitant. Results: Cytochrome P450 3A4 and 2C9 mRNA levels increased ~4- and 2-fold, respectively, over time. Cytochrome P450 3A4 induction was confirmed using reporter assays. We also assessed L-755446, a major metabolite of aprepitant that lacks a triazole ring. Both compounds dose-dependently increased reporter activity; however, induction by L-755446 was stronger than that by aprepitant. Conclusion: These results indicate that aprepitant initially inhibited voriconazole metabolism via its triazole ring and increased cytochrome P450 3A4 induction following L-755446 formation. The decrease in plasma voriconazole concentration 7 days after fosaprepitant administration was mainly attributed to cytochrome P450 3A4 induction by L-755446.
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Hydrogen (H2) protects against inflammation-induced oxidative stress. Nondigestible saccharides (NDSs) enhance colonic H2 production. We examined whether colonic H2 transfers to tissues in the abdominal cavity and whether it affects expression of proinflammatory cytokines. In Expts. 1 and 2, rats were fed diets containing fructooligosaccharides [FOSs; 25 (Expt. 1) and 50 g/kg (Expts. 1 and 2)] for 7 and 14 d, respectively. The no-FOS diet was used as the control diet. At the end of the experiment, H2 excretion and the portal H2 concentration were significantly greater in the FOS group than in the control group. In the FOS group, the arterial H2 concentration was no more than 1.5% of the portal H2 concentration (P = 0.03). The H2 concentration in abdominal cavity tissues, especially adipose tissue, in the FOS group was 5.6- to 43-fold of that in the control group (P < 0.05). The H2 content in the abdominal cavity in the FOS group was 11-fold of that in the control group (P < 0.05). In Expt. 3, rats were fed a high-fat diet containing FOS and inulin (50 g/kg) for 28 d. The area under the curve for H2 excretion between 0 and 28 d and portal and adipose H2 concentrations were significantly higher in the FOS and inulin groups than in the high-fat control group. Adipose mRNA abundance of nuclear factor kappa-light-chain-enhancer of activated B cells 1 was lower in the FOS group than in the control group (P = 0.02) and those of interleukin-6 and chemokine (C-C motif) ligand 2 tended to be lower (P < 0.11). Colonic H2 generated from NDS diffuses to the abdominal cavity before transferring to abdominal tissues. Reduced cytokine expression by FOS feeding might be dependent on increased colonic H2. Colonic H2 may have important implications in the suppressive effect on metabolic syndrome via oxidative stress.
Assuntos
Cavidade Abdominal , Tecido Adiposo/metabolismo , Colo/metabolismo , Citocinas/genética , Frutanos/metabolismo , Hidrogênio/metabolismo , RNA Mensageiro/metabolismo , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Background: Voriconazole therapy for fungal infections usually continues for several years and is often administered on an outpatient basis. Maintaining the voriconazole plasma concentration in the therapeutic range is highly important for effective therapy; however, it is difficult to obtain sufficient information to assess the voriconazole concentration in outpatients. Therefore, we developed a method to simultaneously measure the plasma concentrations of voriconazole and its major metabolite, voriconazole N-oxide, to obtain rapid results after outpatient blood collection and before medical consultation and to attain a better understanding of adherence and the drug-drug interactions of voriconazole. Methods: Fifty microliters of patient plasma was deproteinized with methanol, injected into the liquid chromatography-tandem mass spectrometry system, and purified using an online column. Separation was achieved on an InertSustain C18 column (2.1 mm id × 50 mm, 2 µm) with a mobile phase of 30:70 (0.1% formic acid in water:methanol) at a flow rate of 0.2 mL/min. Detection was performed using electrospray ionization in positive ion multiple reaction monitoring mode. Results: The analysis time was 4 min. The calibration curve was linear, in the range of 0.1 µg/mL to 20 µg/mL for voriconazole and 0.05 µg/mL to 10 µg/mL for voriconazole N-oxide, with a coefficient of determination at R2 > 0.999. Conclusion: There is no need to dilute the patient's plasma even if the concentration of voriconazole is near the upper limit of measurement. Furthermore, the short measurement-time could immediately inform physicians of the patient's voriconazole concentration during ambulatory medical care. Simultaneous measurement of voriconazole and voriconazole N-oxide may also be useful for the immediate adjustment of voriconazole dosage in outpatients and would help us to understand adherence or drug-drug interactions in plasma voriconazole concentrations.
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We investigated whether the feeding of high H2-generating dietary fibre and resistant starch (RS) could suppress hepatic ischaemia-reperfusion (IR) injury, which results from oxidative stress, in rats fed a pectin (Pec) or high-amylose maize starch (HAS) diet. Male Sprague-Dawley rats were fed a control (C) diet, with or without Pec (0-5 % Pec) or HAS (0-30 % HAS) supplementation for 7 d. Portal H2 concentration showed a significant dose-dependent increase with the amount of Pec or HAS supplementation. Plasma alanine and aspartate aminotransferase activities remarkably increased in the C rats (5 % cellulose) due to IR treatment, while it decreased significantly or showed tendencies to decrease in 5 % Pec and 20 % HAS diet-fed rats. The hepatic oxidised glutathione (GSSG):total glutathione ratio increased significantly in IR rats maintained on the C diet compared with sham-operated rats. On the other hand, reduced glutathione (GSH):total glutathione and GSH:GSSG ratios decreased significantly. The GSSG:total glutathione ratio that increased due to IR treatment decreased significantly on HAS and Pec intake, while GSH:total glutathione and GSH:GSSG ratios increased significantly. Hepatic sinusoids of IR rats fed the C diet were occluded, but those of IR rats fed the Pec diet were similar to those in the sham-operated rats. In conclusion, we found that Pec or HAS, which enhance H2 generation in the large intestine, alleviated hepatic IR injury. The present study demonstrates another physiological significance of dietary fibre and RS.
Assuntos
Hidrogênio/sangue , Isquemia/fisiopatologia , Fígado/patologia , Pectinas/uso terapêutico , Prebióticos , Traumatismo por Reperfusão/dietoterapia , Amido/uso terapêutico , Amilose/administração & dosagem , Amilose/análise , Amilose/uso terapêutico , Animais , Ceco/microbiologia , Fermentação , Glutationa , Hepatopatia Veno-Oclusiva/etiologia , Hepatopatia Veno-Oclusiva/fisiopatologia , Hidrogênio/metabolismo , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/fisiopatologia , Masculino , Oxirredução , Estresse Oxidativo , Pectinas/administração & dosagem , Prebióticos/análise , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Sementes/química , Amido/administração & dosagem , Amido/química , Amido/metabolismo , Zea mays/químicaRESUMO
Non-polyadenylated mRNAs of replication-dependent histones (RDHs) are synthesized by RNA polymerase II (Pol II) at histone locus bodies (HLBs). HLBs frequently associate with Cajal bodies (CBs), in which 3'-end processing factors for RDH genes are enriched; however, this association's role in transcription termination of RDH genes remains unclear. Here, we show that Pol II pauses immediately upstream of transcript end sites of RDH genes and Mediator plays a role in this Pol II pausing through CBs' association with HLBs. Disruption of the Mediator docking site for Little elongation complex (LEC)-Cap binding complex (CBC)-Negative elongation factor (NELF), components of CBs, interferes with CBs' association with HLBs and 3' Pol II pausing, resulting in increased aberrant unprocessed RDH gene transcripts. Our findings suggest Mediator's involvement in CBs' association with HLBs to facilitate 3' Pol II pausing and subsequent 3'-end processing of RDH genes by supplying 3'-end processing factors.
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Corpos Enovelados , Histonas , Corpos Enovelados/metabolismo , Histonas/metabolismo , Corpos Nucleares , RNA Polimerase II/metabolismo , Transcrição GênicaRESUMO
The purpose of this study was to assess the risk factors for clozapine-induced central nervous system (CNS) abnormalities (i.e., electroencephalogram [EEG] abnormalities, myoclonus, and seizures). We retrospectively analyzed data from 106 patients with schizophrenia who received clozapine treatment through our hospital. A review of the EEG recordings showed that 71 of these patients (67.0 %) developed CNS abnormalities after initiating clozapine treatment. EEG abnormalities, myoclonus, and seizures occurred in 53.8 %, 38.7 %, and 8.5 % of the patients, respectively. Multivariate logistic regression analysis showed that the risk factors for clozapine-induced CNS abnormalities were concomitant lithium usage (odds ratio, 4.560; 95 % confidence interval, 1.750-11.900) and shorter illness durations before clozapine initiation (odds ratio, 0.796; 95 % confidence interval, 0.649-0.976). However, plasma clozapine levels and the usage of antiepileptics did not exhibit associations with the risks of CNS abnormalities. Clinicians should monitor their patients for incident CNS abnormalities when administering lithium in combination with clozapine regardless of plasma clozapine levels or the usage of antiepileptics. This is especially true for patients with short illness durations.
Assuntos
Antipsicóticos , Clozapina , Malformações do Sistema Nervoso , Esquizofrenia , Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Eletroencefalografia , Humanos , Japão , Malformações do Sistema Nervoso/tratamento farmacológico , Estudos Retrospectivos , Fatores de Risco , Esquizofrenia/tratamento farmacológicoRESUMO
Regarding the process of uveitis development, many past studies have used the experimental autoimmune uveoretinitis (EAU) and other animal models to observe histologically the infiltration of inflammatory cells and the process of lesion progression. However, no detailed study of the process of clearance of infiltrated inflammatory cells from the eye has been reported. The purpose of this study was to investigate the process of clearance of polymorphonuclear leukocytes (PMNs) using an experimental hypopyon model. PMNs obtained from ascites of SD rat were injected into the anterior chamber of SD rats. The process of PMNs clearance was evaluated by serial photography and 3D optical coherence tomography (3D-OCT), and histological changes were observed simultaneously. The hypopyon heights regressed from 1.04±0.06 mm at 1h (day 0) to 0.45±0.07 mm at day 1, and 0 mm at day 3 after PMNs injection. When the hypopyon heights at the three time points were compared, significant differences were found between groups (P<0.05). The hypopyon volumes also decreased from 1.46±0.07 mm(3) at 1h to 1.16±0.09 mm(3) at 2h, and 0.83±0.04 mm(3) at 3h after PMN injection. When the hypopyon volumes at the three time points were compared, significant differences were found between groups (P<0.05). Light micrographs of inferior segment of the eyeball revealed dense PMNs in the chamber angle at 1h after PMNs injection and many PMNs in the iris stroma and vessels, as well as at the episcleral and subconjunctival tissues around limbus at 3h and day 1 after PMNs injection. Light micrographs of superior segment of the eyeball at 3h after injection revealed PMNs in the episcleral and subconjunctival vessels. Electron micrographs of inferior segment of the eyeball at 3h after PMNs injection revealed dense PMNs with slightly condensed nuclei in the anterior chamber, as well as in the iris stroma and vessels. In conclusion, in the experimental hypopyon model, PMNs injected into the anterior chamber were cleared from the eye mainly through the iris stroma and vessels, as well as the episcleral and subconjunctival tissues around limbus.
Assuntos
Câmara Anterior/metabolismo , Modelos Animais de Doenças , Neutrófilos/metabolismo , Uveíte Supurativa/metabolismo , Animais , Câmara Anterior/patologia , Imageamento Tridimensional , Cinética , Neutrófilos/patologia , Ratos , Ratos Sprague-Dawley , Tomografia de Coerência Óptica , Uveíte Supurativa/patologiaRESUMO
Appropriate gene expression is essential for producing the correct amount of proteins at the right time, which is critical for living organisms. In the three-dimensional (3D) space of the nucleus, genomes are folded into higher order chromatin structures that are intimately associated with epigenetic factors, including histone modifications and nuclear long non-coding RNAs (lncRNAs). LncRNAs regulate transcription for both activation and repression, either in cis or in trans. Many ncRNAs are expressed in development-specific, differentiation-specific, and disease-specific manners, suggesting that they are critical regulators for organ generation and maintenance. In this review, we mainly describe the following ncRNAs: Xist, involved in X chromosome inactivation, Firre, which serves as a platform for trans-chromosomal associations, and UMLILO and ELEANORS, which co-regulate genes involved in the immune response and breast cancer, respectively. These ncRNAs are gene regulators in the context of the 3D genome structure.