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1.
Med Mol Morphol ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39141108

RESUMEN

Invasive fungal infections including invasive pulmonary aspergillosis (IPA) generally have a poor prognosis, because the fungi spread throughout various organs. Therefore, it is important to accurately identify the fungal species for treatment. In this article, we present the results of pathological and molecular morphological analyses that were performed to elucidate the cause of respiratory failure in a patient who died despite suspicion of IPA and treatment with micafungin (MCFG). Pathological analysis revealed the existence of cystic and linear fungi in lung tissue. The fungi were identified as Aspergillus fumigatus (A. fumigatus) by partial sequencing of genomic DNA. Correlative light microscopy and electron microscopy (CLEM) analysis confirmed that fungi observed with light microscopy can also be observed with scanning electron microscopy (SEM) using formalin-fixed paraffin-embedded tissue sections. SEM revealed an atypical ultrastructure of the fungi including inhomogeneous widths, rough surfaces, and numerous cyst-like structures of various sizes. The fungi showed several morphological changes of cultured A. fumigatus treated with MCFG that were previously reported. Our results indicate that integrated analysis of ultrastructural observation by SEM and DNA sequencing may be an effective tool for analyzing fungi that are difficult to identify by conventional pathological analysis.

2.
Heart Vessels ; 38(6): 785-792, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36802023

RESUMEN

Risk prediction for heart failure (HF) using machine learning methods (MLM) has not yet been established at practical application levels in clinical settings. This study aimed to create a new risk prediction model for HF with a minimum number of predictor variables using MLM. We used two datasets of hospitalized HF patients: retrospective data for creating the model and prospectively registered data for model validation. Critical clinical events (CCEs) were defined as death or LV assist device implantation within 1 year from the discharge date. We randomly divided the retrospective data into training and testing datasets and created a risk prediction model based on the training dataset (MLM-risk model). The prediction model was validated using both the testing dataset and the prospectively registered data. Finally, we compared predictive power with published conventional risk models. In the patients with HF (n = 987), CCEs occurred in 142 patients. In the testing dataset, the substantial predictive power of the MLM-risk model was obtained (AUC = 0.87). We generated the model using 15 variables. Our MLM-risk model showed superior predictive power in the prospective study compared to conventional risk models such as the Seattle Heart Failure Model (c-statistics: 0.86 vs. 0.68, p < 0.05). Notably, the model with an input variable number (n = 5) has comparable predictive power for CCE with the model (variable number = 15). This study developed and validated a model with minimized variables to predict mortality more accurately in patients with HF, using a MLM, than the existing risk scores.


Asunto(s)
Inteligencia Artificial , Insuficiencia Cardíaca , Humanos , Estudios Retrospectivos , Estudios Prospectivos , Pronóstico , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/terapia , Algoritmos
3.
Exp Cell Res ; 399(1): 112444, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33347855

RESUMEN

The splicing machinery heavily contributes to biological complexity and especially to the ability of cells to adapt to altered cellular conditions. Hypoxia also plays a key role in the pathophysiology of many disease states. Recent studies have revealed that tumorigenesis and hypoxia are involved in large-scale alterations in alternative pre-mRNA splicing. Fas pre-mRNA is alternatively spliced by excluding exon 6 to produce soluble Fas (sFas) protein that lacks a transmembrane domain and acts by inhibiting Fas mediated apoptosis. In the present study we show that U2AF is involved in hypoxia dependent anti-apoptotic Fas mRNA isoform formation. Our performed studies show that U2AF-RNA interaction is reduced in hypoxic cells, leading to reduction of Fas and increased sFas mRNAs formation. Efficient U2AF-RNA interactions of both subunits are important for Fas exon 6 inclusion into forming mRNA in normoxic and hypoxic cells.


Asunto(s)
Hipoxia/genética , Factor de Empalme U2AF/fisiología , Receptor fas/genética , Empalme Alternativo/genética , Células HCT116 , Humanos , Hipoxia/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Precursores del ARN/genética , Precursores del ARN/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Empalme U2AF/genética , Receptor fas/metabolismo
4.
Diabetologia ; 59(3): 533-41, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26693710

RESUMEN

AIMS/HYPOTHESIS: Glucose-dependent insulinotropic polypeptide (GIP) is a peptide hormone released from gut K cells. While the predominant form is GIP(1-42), a shorter form, GIP(1-30), is produced by pancreatic alpha cells and promotes insulin secretion in a paracrine manner. Here, we elucidated whether GIP(1-30) expression is modulated in mouse models of diabetes. We then investigated whether PEGylated GIP(1-30) can improve islet function and morphology as well as suppress the progression to hyperglycaemia in mice treated with low-dose streptozotocin (LD-STZ). METHODS: We examined pancreatic GIP immunoreactivity in rodent diabetic models. We synthesised [D-Ala(2)]GIP(1-30) and modified the C-terminus with polyethylene glycol (PEG) to produce a dipeptidyl peptidase-4 (DPP-4)-resistant long-acting GIP analogue, [D-Ala(2)]GIP(1-30)-PEG. We performed i.p.GTT and immunohistochemical analysis in non-diabetic and LD-STZ diabetic mice, with or without administration of [D-Ala(2)]GIP(1-30)-PEG. RESULTS: Pancreatic GIP expression was concomitantly enhanced with alpha cell expansion in rodent models of diabetes. Treatment with DPP-4 inhibitor decreased both the GIP- and glucagon-positive areas and preserved the insulin-positive area in LD-STZ diabetic mice. Body weight was not affected by [D-Ala(2)]GIP(1-30)-PEG in LD-STZ or non-diabetic mice. Treatment with GIP significantly ameliorated chronic hyperglycaemia and improved glucose excursions in LD-STZ mice. Treatment with GIP also reduced alpha cell expansion in the islets and suppressed plasma glucagon levels compared with non-treated LD-STZ mice. Additionally, [D-Ala(2)]GIP(1-30)-PEG preserved beta cell area via inhibition of apoptosis in LD-STZ mice. CONCLUSIONS/INTERPRETATION: Our data suggest that GIP(1-30) expression is upregulated in diabetes, and PEGylated GIP(1-30) can suppress the progression to STZ-induced hyperglycaemia by inhibiting beta cell apoptosis and alpha cell expansion.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Polipéptido Inhibidor Gástrico/metabolismo , Polipéptido Inhibidor Gástrico/uso terapéutico , Hiperglucemia/tratamiento farmacológico , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/uso terapéutico , Animales , Peso Corporal/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Polipéptido Inhibidor Gástrico/química , Glucagón/metabolismo , Hiperglucemia/inducido químicamente , Hipoglucemiantes/química , Hipoglucemiantes/metabolismo , Hipoglucemiantes/uso terapéutico , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Fragmentos de Péptidos/química , Estreptozocina/farmacología
5.
J Biol Chem ; 290(29): 18079-18089, 2015 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-26023237

RESUMEN

The removal of introns from mRNA precursors (pre-mRNAs) is an essential step in eukaryotic gene expression. The splicing machinery heavily contributes to biological complexity and especially to the ability of cells to adapt to altered cellular conditions. Inhibitory PAS domain protein (IPAS), a dominant negative regulator of hypoxia-inducible gene expression, is generated from hypoxia inducible transcription factor-3α (HIF-3α) pre-mRNA by an alternative splicing mechanism. Inactivation of the IPAS transcript in mice leads to the neo-vascularization of the cornea, suggesting that IPAS is an important regulator of anti-angiogenesis in this tissue. For the first time we demonstrate that serine-arginine (SR) proteins are involved in oxygen tension-dependent changes in pre-mRNA splicing. SR proteins isolated from hypoxic cells differentially interact with RNA (compared with proteins isolated from cells cultured under normoxic conditions). They possess the differential ability to activate hypoxia-dependent splice sites, and they are more phosphorylated than those isolated from normoxic HeLa cells. We also show that expression of SR protein kinases (CLK1, SRPK1, SRPK2) in hypoxic cells is elevated at mRNA and protein levels. Increased expression of CLK1 kinase is regulated by HIFs. Reduction of CLK1 cellular expression levels reduces hypoxia-dependent full-length carbonic anhydrase IX (CAIX) mRNA and CAIX protein formation and changes hypoxia-dependent cysteine-rich angiogenic inducer 61 (Cyr61) mRNA isoform formation profiles.


Asunto(s)
Empalme Alternativo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Hipoxia/metabolismo , Oxígeno/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Precursores del ARN/genética , Arginina/genética , Arginina/metabolismo , Hipoxia de la Célula , Regulación Enzimológica de la Expresión Génica , Células HeLa , Humanos , Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Precursores del ARN/metabolismo , Serina/genética , Serina/metabolismo
6.
Mod Rheumatol ; 26(6): 817-827, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26915909

RESUMEN

OBJECTIVES: We investigated whether the maintenance of routine assessment of patient index data 3 (RAPID3) remission for one year (RAPID3-MR) may predict good radiographic outcomes. We also compared radiographic progression to prognostic factors among patients with RAPID3-MR, with the maintenance of clinical disease activity index remission for one year (CDAI-MR) or with the maintenance of 28 joint count disease activity score remission for one year (DAS28-MR). METHODS: Of 1220 patients with available clinical data, 92 with RAPID3-MR, 80 with RAPID3-NMR (not satisfying RAPID3-MR), 45 with CDAI-MR, and 75 with DAS28-MR were retrospectively investigated. CDAI and DAS28 for clinical outcomes and the modified total Sharp score (mTSS) for radiographic joint damage were investigated for at least one year. RESULTS: RAPID3, CDAI, DAS28, and their categories remained unchanged or significantly improved in RAPID3-MR patients but significantly deteriorated in RAPID3-NMR patients. The mean annual ΔmTSS was significantly lower in RAPID3-MR patients (0.12 ± 0.55) than in RAPID3-NMR patients (0.54 ± 1.27) (p = 0.025). There was no significant difference among RAPID3-MR patients, CDAI-MR patients (0.06 ± 0.85), and DAS28-MR patients (0.11 ± 0.89). The baseline mTSS (p = 0.038) and monotherapy with nonbiological disease-modifying antirheumatic drugs (p = 0.033) were good prognostic factors in RAPID3-MR patients. CONCLUSIONS: One-year RAPID3 remission maintenance may predict good radiographic outcomes.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Adulto , Artritis Reumatoide/diagnóstico por imagen , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Resultados Informados por el Paciente , Pronóstico , Inducción de Remisión , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
7.
Mod Rheumatol ; 26(5): 651-61, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26698929

RESUMEN

OBJECTIVES: To investigate the efficacy and safety of etanercept (ETN) in patients with rheumatoid arthritis (RA) with moderate disease activity and the possibility to discontinue ETN after achieving remission. METHODS: Multicenter, randomized, and open-label study was conducted in Japan and Korea. RA patients (disease duration <5 years) with moderate disease activity despite methotrexate (MTX) treatment were allocated to either MTX or ETN + MTX (Period 1) for 12 months. Patients who achieved sustained remission defined as DAS28 < 2.6 at both 6 and 12 months in the ETN + MTX group, were randomized to either continue or discontinue ETN for 12 months (Period 2). RESULTS: A total of 222 patients were enrolled in Period 1 and clinical remission was achieved in 106/157 (67.5%) and 5/28 (17.9%) patients in the ETN + MTX and MTX groups, respectively. In Period 2, sixty-seven patients were randomized and finally 28/32 (87.5%) and 15/28 (53.6%) patients who continued or discontinued ETN maintained clinical remission. Baseline disease activity and the presence of comorbid diseases influenced the maintenance of remission after ETN discontinuation. CONCLUSIONS: ETN + MTX was efficient for RA patients with moderate disease activity into remission. After achieving sustained remission, a half of the patients who discontinued ETN could maintain remission for 1 year.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Etanercept/uso terapéutico , Inducción de Remisión/métodos , Adulto , Anciano , Artritis Reumatoide/diagnóstico , Quimioterapia Combinada , Femenino , Humanos , Japón , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Estudios Prospectivos , República de Corea , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Privación de Tratamiento
8.
Curr Opin Nephrol Hypertens ; 24(1): 67-73, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25415611

RESUMEN

PURPOSE OF REVIEW: Dipeptidyl peptidase-4 (DPP-4) inhibitors are incretin-based drugs approved for the treatment of type 2 diabetes. The main action of DPP-4 inhibitors is to increase the level of incretin hormones such as glucagon-like peptide-1 (GLP-1), thereby stimulating insulin secretion from pancreatic ß cells. Recently emerging evidence suggests the pleiotropic extrapancreatic function of GLP-1 or DPP-4 inhibitors, including kidney and cardiovascular protection. Here, we review the effects of DPP-4 inhibitors on progressive kidney disease such as diabetic nephropathy from a therapeutic point of view. RECENT FINDINGS: A growing number of studies in animal models and human diseases have shown that DPP-4 inhibition ameliorates kidney disease by a process independent of glucose lowering. Possible mechanisms underlying such protective properties include the facilitation of natriuresis and reduction of blood pressure, and also local effects of the reduction of oxidative stress, inflammation and improvement of endothelial function in the kidney. DPP-4 inhibitors may also restore other DPP-4 substrates which have proven renal effects. SUMMARY: Treatment of diabetes with DPP-4 inhibitors is likely to involve a variety of extrapancreatic effects including renal protection. Such pleiotropic action of DPP-4 inhibitors might occur by both incretin-dependent and incretin-independent mechanisms. Conclusive evidence is needed to translate the favorable results from animal models to humans.


Asunto(s)
Nefropatías Diabéticas/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Incretinas/metabolismo , Animales , Nefropatías Diabéticas/enzimología , Polipéptido Inhibidor Gástrico/metabolismo , Péptido 1 Similar al Glucagón/metabolismo , Humanos , Riñón/efectos de los fármacos , Riñón/enzimología
9.
Am J Physiol Endocrinol Metab ; 306(9): E1065-76, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24619881

RESUMEN

Defects in glucose uptake by the skeletal muscle cause diseases linked to metabolic disturbance such as type 2 diabetes. The molecular mechanism determining glucose disposal in the skeletal muscle in response to cellular stimuli including insulin, however, remains largely unknown. The hypoxia-inducible factor-1α (HIF-1α) is a transcription factor operating in the cellular adaptive response to hypoxic conditions. Recent studies have uncovered pleiotropic actions of HIF-1α in the homeostatic response to various cellular stimuli, including insulin under normoxic conditions. Thus we hypothesized HIF-1α is involved in the regulation of glucose metabolism stimulated by insulin in the skeletal muscle. To this end, we generated C2C12 myocytes in which HIF-1α is knocked down by short-hairpin RNA and examined the intracellular signaling cascade and glucose uptake subsequent to insulin stimulation. Knockdown of HIF-1α expression in the skeletal muscle cells resulted in abrogation of insulin-stimulated glucose uptake associated with impaired mobilization of glucose transporter 4 (GLUT4) to the plasma membrane. Such defect seemed to be caused by reduced phosphorylation of the protein kinase B substrate of 160 kDa (AS160). AS160 phosphorylation and GLUT4 translocation by AMP-activated protein kinase activation were abrogated as well. In addition, expression of the constitutively active mutant of HIF-1α (CA-HIF-1α) or upregulation of endogenous HIF-1α in C2C12 cells shows AS160 phosphorylation comparable to the insulin-stimulated level even in the absence of insulin. Accordingly GLUT4 translocation was increased in the cells expressing CA-HIF1α. Taken together, HIF-1α is a determinant for GLUT4-mediated glucose uptake in the skeletal muscle cells thus as a possible target to alleviate impaired glucose metabolism in, e.g., type 2 diabetes.


Asunto(s)
Transportador de Glucosa de Tipo 4/metabolismo , Glucosa/metabolismo , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Músculo Esquelético/metabolismo , Animales , Células Cultivadas , Proteínas Activadoras de GTPasa/metabolismo , Técnicas de Silenciamiento del Gen , Insulina/farmacología , Ratones , Ratones Transgénicos , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efectos de los fármacos , Transporte de Proteínas/efectos de los fármacos , Transporte de Proteínas/genética
10.
Proc Natl Acad Sci U S A ; 108(20): 8450-5, 2011 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-21536866

RESUMEN

Phosphorylation of the GluA1 subunit of AMPA receptors has been proposed to regulate receptor trafficking and synaptic transmission and plasticity. However, it remains unclear whether GluA1 phosphorylation is permissive or sufficient for enacting these functional changes. Here we investigate the role of GluA1 phosphorylation at S831 and S845 residues in the hippocampus through the analyses of GluA1 S831D/S845D phosphomimetic knock-in mice. S831D/S845D mice showed normal total and surface expression and subcellular localization of GluA1 as well as intact basal synaptic transmission. In addition, theta-burst stimulation, a protocol that was sufficient to induce robust long-term potentiation (LTP) in WT mice, resulted in LTP of similar magnitude in S831D/S845D mice. However, S831D/S845D mice showed LTP induced with 10-Hz stimulation, a protocol that is weaker than theta-burst stimulation and was not sufficient to induce LTP in WT mice. Moreover, S831D/S845D mice exhibited LTP induced with spike-timing-dependent plasticity (STDP) protocol at a long pre-post interval that was subthreshold for WT mice, although a suprathreshold STDP protocol at a short pre-post interval resulted in similarly robust LTP for WT and S831D/S845D mice. These results indicate that phosphorylation of GluA1 at S831 and S845 is sufficient to lower the threshold for LTP induction, increasing the probability of synaptic plasticity.


Asunto(s)
Potenciación a Largo Plazo , Mutación , Plasticidad Neuronal , Receptores AMPA/genética , Animales , Hipocampo , Ratones , Fosforilación , Receptores AMPA/metabolismo , Transmisión Sináptica
11.
PLoS One ; 19(5): e0300751, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38717999

RESUMEN

Transcriptional response to changes in oxygen concentration is mainly controlled by hypoxia-inducible transcription factors (HIFs). Besides regulation of hypoxia-responsible gene expression, HIF-3α has recently been shown to be involved in lung development and in the metabolic process of fat tissue. However, the precise mechanism for such properties of HIF-3α is still largely unknown. To this end, we generated HIF3A gene-disrupted mice by means of genome editing technology to explore the pleiotropic role of HIF-3α in development and physiology. We obtained adult mice carrying homozygous HIF3A gene mutations with comparable body weight and height to wild-type mice. However, the number of litters and ratio of homozygous mutation carriers born from the mating between homozygous mutant mice was lower than expected due to sporadic deaths on postnatal day 1. HIF3A gene-disrupted mice exhibited abnormal configuration of the lung such as a reduced number of alveoli and thickened alveolar walls. Transcriptome analysis showed, as well as genes associated with lung development, an upregulation of stearoyl-Coenzyme A desaturase 1, a pivotal enzyme for fatty acid metabolism. Analysis of fatty acid composition in the lung employing gas chromatography indicated an elevation in palmitoleic acid and a reduction in oleic acid, suggesting an imbalance in distribution of fatty acid, a constituent of lung surfactant. Accordingly, administration of glucocorticoid injections during pregnancy resulted in a restoration of normal alveolar counts and a decrease in neonatal mortality. In conclusion, these observations provide novel insights into a pivotal role of HIF-3α in the preservation of critically important structure and function of alveoli beyond the regulation of hypoxia-mediated gene expression.


Asunto(s)
Proteínas Reguladoras de la Apoptosis , Alveolos Pulmonares , Proteínas Represoras , Animales , Femenino , Masculino , Ratones , Animales Recién Nacidos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Translocador Nuclear del Receptor de Aril Hidrocarburo/genética , Translocador Nuclear del Receptor de Aril Hidrocarburo/metabolismo , Ácidos Grasos/metabolismo , Alveolos Pulmonares/metabolismo , Alveolos Pulmonares/patología , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Estearoil-CoA Desaturasa/genética , Estearoil-CoA Desaturasa/metabolismo
12.
Sci Transl Med ; 16(768): eadh9763, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39383245

RESUMEN

Early life stress (ELS) yields cognitive impairments of unknown molecular and physiological origin. We found that fragmented maternal care of mice during a neonatal critical period from postnatal days P2-9 elevated dopamine receptor D2R and suppressed D4R expression, specifically within the anterior cingulate cortex (ACC) in only the male offspring. This was associated with poor performance on a two-choice visual attention task, which was acutely rescued in adulthood by local or systemic pharmacological rebalancing of D2R/D4R activity. Furthermore, ELS male mice demonstrated heightened hypothalamic orexin and persistently disrupted sleep. Given that acute sleep deprivation in normally reared male mice mimicked the ACC dopamine receptor subtype modulation and disrupted attention of ELS mice, sleep loss likely underlies cognitive deficits in ELS mice. Likewise, sleep impairment mediated the attention deficits associated with early adversity in human children, as demonstrated by path analysis on data collected with multiple questionnaires for a large child cohort. A deeper understanding of the sex-specific cognitive consequences of ELS thus has the potential to reveal therapeutic strategies for overcoming them.


Asunto(s)
Atención , Sueño , Animales , Masculino , Femenino , Sueño/fisiología , Estrés Psicológico/metabolismo , Estrés Psicológico/complicaciones , Humanos , Ratones , Receptores de Dopamina D2/metabolismo , Ratones Endogámicos C57BL , Giro del Cíngulo/metabolismo , Privación de Sueño/metabolismo , Orexinas/metabolismo , Hipotálamo/metabolismo , Receptores Dopaminérgicos/metabolismo , Niño , Privación Materna
13.
J Neurophysiol ; 109(4): 1174-81, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23197456

RESUMEN

Brief strong depolarization of cerebellar Purkinje cells produces a slow inward cation current [depolarization-induced slow current (DISC)]. Previous work has shown that DISC is triggered by voltage-sensitive Ca influx in the Purkinje cell and is attenuated by blockers of vesicular loading and fusion. Here, we have sought to characterize the ion channel(s) underlying the DISC conductance. While the brief depolarizing steps that triggered DISC were associated with a large Ca transient, the onset of DISC current corresponded only with the Ca transient decay phase. Furthermore, substitution of external Na with the impermeant cation N-methyl-d-glucamine produced a complete and reversible block of DISC, suggesting that the DISC conductance was not Ca permeant. Transient receptor potential cation channel, subfamily M, members 4 (TRPM4) and 5 (TRPM5) are nonselective cation channels that are opened by Ca transients but do not flux Ca. They are expressed in Purkinje cells of the posterior cerebellum, where DISC is large, and, in these cells, DISC is strongly attenuated by nonselective blockers of TRPM4/5. However, measurement of DISC currents in Purkinje cells derived from TRPM4 null, TRPM5 null, and double null mice as well as wild-type mice with TRPM4 short hairpin RNA knockdown showed a partial attenuation with 35-46% of current remaining. Thus, while the DISC conductance is Ca triggered, Na permeant, and Ca impermeant, suggesting a role for TRPM4 and TRPM5, these ion channels are not absolutely required for DISC.


Asunto(s)
Potenciales de Acción/fisiología , Células de Purkinje/fisiología , Potenciales de Acción/efectos de los fármacos , Animales , Calcio/metabolismo , Meglumina/análogos & derivados , Meglumina/farmacología , Ratones , Ratones Endogámicos C57BL , Células de Purkinje/metabolismo , ARN Interferente Pequeño , Sodio/metabolismo , Canales Catiónicos TRPM/antagonistas & inhibidores , Canales Catiónicos TRPM/genética , Canales Catiónicos TRPM/metabolismo
14.
Biochem Biophys Res Commun ; 441(2): 499-506, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24383088

RESUMEN

GLI-similar 1 (GLIS1) is important for the reprogramming of fibroblasts into induced pluripotent stem cells (iPSCs). However, the molecular mechanisms of regulation of GLIS1 expression remain unclear. We have therefore examined GLIS1 expression in various cancer cell lines and demonstrated that GLIS1 expression was dramatically increased under hypoxic conditions. Importantly, GLIS1 expression was significantly attenuated in VHL-overexpressing renal cell carcinoma cells compared to the VHL-deficient parent control. Moreover, promoter analysis demonstrated that GLIS1 transcription was regulated by hypoxia through a hypoxia-inducible factors (HIFs)-dependent mechanism. Co-transfection experiments revealed that HIF-2α had greater potency on the GLIS1 promoter activation than HIF-1α. Subsequent studies using wild-type and mutant HIF-2α demonstrated that DNA binding activity was not necessary but TADs were critical for GLIS1 induction. Finally, co-transfection experiments indicated that HIF-2α cooperated with AP-1 family members in upregulating GLIS1 transcription. These results suggest that the hypoxic signaling pathway may play a pivotal role in regulating the reprogramming factor GLIS1, via non-canonical mechanisms involving partner transcription factor rather than by direct HIF transactivation.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/química , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Hipoxia de la Célula/genética , Línea Celular Tumoral , Humanos , Factor 1 Inducible por Hipoxia , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Regiones Promotoras Genéticas , Estructura Terciaria de Proteína , Factor de Transcripción AP-1/metabolismo
15.
Brain Nerve ; 75(10): 1115-1120, 2023 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-37849361

RESUMEN

We discuss leveraging a cutting-edge technology known as the Metaverse to tackle healthcare challenges, with a particular focus on enhancing patient satisfaction and improving working conditions for medical professionals. We plan to achieve this by improving real-digital collaboration and utilizing the advantages of the Metaverse, such as novel communication and experiences and increased work efficiency and quality. This article showcases several concrete examples of Metaverse services in the medical field, as demonstrated by the "Medical Metaverse Joint Research Course" established through a collaboration between IBM and Juntendo University, and also highlights possible future prospects.


Asunto(s)
Comunicación , Condiciones de Trabajo , Humanos , Universidades
16.
Kidney Int ; 78(1): 48-59, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20375990

RESUMEN

High glucose evokes a variety of signals in mesangial cells that alter cellular functions responsible for the development of diabetic glomerulopathy. The hypoxia-inducible factor-1alpha (HIF-1alpha) regulates cellular homeostasis under hypoxic conditions, but it also has pleiotropic effects in response to cellular stresses at normoxia. Here we determined whether HIF-1alpha has a role in the regulation of mesangial cells in hyperglycemia. In the streptozotocin-induced diabetic mouse model, glomerular mesangial cells had a significant increase in HIF-1alpha expression in the nucleus. In cultured mesangial cells, high glucose enhanced the expression of HIF-1alpha and its target genes known to be involved in the development of diabetic glomerulopathy. A glucose-responsive carbohydrate response element binding protein (ChREBP) was found to have a critical role in the transcriptional upregulation of HIF-1alpha and downstream gene expression in mesangial cells exposed to high glucose. Knockdown of HIF-1alpha or ChREBP in mesangial cells abrogated the high glucose-mediated perturbation of gene expression. Our results show that ChREBP and HIF-1alpha mediate gene regulation in mesangial cells. Further studies will be needed to find out whether these findings are relevant to the development of the diabetic nephropathy.


Asunto(s)
Glucosa/metabolismo , Glucosa/farmacología , Animales , Núcleo Celular/genética , Núcleo Celular/metabolismo , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Glucosa/genética , Hipoxia/genética , Hipoxia/metabolismo , Factor 1 Inducible por Hipoxia/genética , Factor 1 Inducible por Hipoxia/metabolismo , Masculino , Células Mesangiales/metabolismo , Ratones , Ratones Endogámicos C57BL , Elementos de Respuesta/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Regulación hacia Arriba/efectos de los fármacos
17.
Front Endocrinol (Lausanne) ; 11: 601594, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33362717

RESUMEN

Objective: A low-carbohydrate diet (LC) can be beneficial to obese subjects with type2 diabetes mellitus (T2DM). Sodium-glucose cotransporter 2 inhibitor (SGLT2i) presents prompt glucose-lowering effects in subjects with T2DM. We investigated how LC and SGLT2i could similarly or differently influence on the metabolic changes, including glucose, lipid, and ketone metabolism in lean insulinopenic Akita mice. We also examined the impacts of the combination. Methods: Male Akita mice were fed ad libitum normal-carbohydrate diet (NC) as a control or low-carbohydrate diet (LC) as an intervention for 8 weeks with or without SGLT2i treatment. Body weight and casual bold glucose levels were monitored during the study, in addition to measuring TG, NEFA, and ketone levels. We quantified gene expressions involved in gluconeogenesis, lipid metabolism and ketogenesis in the liver and the kidney. We also investigated the immunostaining analysis of pancreatic islets to assess the effect of islet protection. Results: Both LC and SGLT2i treatment reduced chronic hyperglycemia. Moreover, the combination therapy additionally ameliorated glycemic levels and preserved the islet morphology in part. LC but not SGLT2i increased body weight accompanied by epididymal fat accumulation. In contrast, SGLT2i, not LC potentiated four-fold ketone production with higher ketogenic gene expression, in comparison with the non-treated Akita mice. Besides, the combination did not enhance further ketone production compared to the SGLT2i alone. Conclusions: Our results indicated that both LC and SGLT2i reduced chronic hyperglycemia, and the combination presented synergistic favorable effects concomitantly with amelioration of islet morphology, while the combination did not enhance further ketosis in Akita mice.


Asunto(s)
Diabetes Mellitus Experimental/terapia , Nefropatías Diabéticas/prevención & control , Dieta Baja en Carbohidratos/métodos , Hiperglucemia/terapia , Obesidad/complicaciones , Inhibidores del Cotransportador de Sodio-Glucosa 2/farmacología , Delgadez/complicaciones , Animales , Terapia Combinada , Diabetes Mellitus Experimental/etiología , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Gluconeogénesis , Hiperglucemia/etiología , Hiperglucemia/metabolismo , Hiperglucemia/patología , Insulina/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL
18.
PLoS One ; 15(5): e0233561, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32470016

RESUMEN

Cortical neurons fire intermittently and synchronously during non-rapid eye movement sleep (NREMS), in which active and silent periods are referred to as ON and OFF periods, respectively. Neuronal firing rates during ON periods (NREMS-ON-activity) are similar to those of wakefulness (W-activity), raising the possibility that NREMS-ON neuronal-activity is fragmented W-activity. To test this, we investigated the patterning and organization of cortical spike trains and of spike ensembles in neuronal networks using extracellular recordings in mice. Firing rates of neurons during NREMS-ON and W were similar, but showed enhanced bursting in NREMS with no apparent preference in occurrence, relative to the beginning or end of the on-state. Additionally, there was an overall increase in the randomness of occurrence of sequences comprised of multi-neuron ensembles in NREMS recorded from tetrodes. In association with increased burst firing, somatic calcium transients were increased in NREMS. The increased calcium transients associated with bursting during NREM may activate calcium-dependent, cell-signaling pathways for sleep related cellular processes.


Asunto(s)
Neuronas/fisiología , Sueño de Onda Lenta , Vigilia , Animales , Electroencefalografía , Masculino , Ratones , Ratones Endogámicos C57BL
19.
Nihon Rinsho ; 67(8): 1627-35, 2009 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-19768953

RESUMEN

Diabetic nephropathy has emerged as the leading cause of end-stage renal disease. Intensive control of blood glucose and pressure has been the mainstay for the treatment of diabetic nephropathy and provided favorable evidence in slowing disease progression. However, current therapeutic regimens have not demonstrated satisfactory prevention of the nephropathy thus novel therapeutic agents are urgently needed. In diabetic conditions, multiple mechanisms have been implicated in glucose-mediated microvascular damage leading to nephropathy; activation of protein kinase C, accumulation of inflammatory mediators and advanced glycation end products, generation of reactive oxygen species, and other biochemical abnormalities. In turn, inhibiting these pathological mechanisms may represent a potential therapy for diabetic nephropathy. This review discusses current concepts innovel targeted therapy for diabetic kidney complications.


Asunto(s)
Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/metabolismo , Humanos
20.
Cell Rep ; 29(12): 3835-3846.e5, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31851917

RESUMEN

The long-term storage of episodic memory requires communication between prefrontal cortex and hippocampus. However, how consolidation alters dynamic interactions between these regions during subsequent recall remains unexplored. Here we perform simultaneous electrophysiological recordings from anterior cingulate cortex (ACC) and hippocampal CA1 in mice during recall of recent and remote contextual fear memory. We find that, in contrast to recent memory, remote memory recall is accompanied by increased ACC-CA1 synchronization at multiple frequency bands. The augmented ACC-CA1 interaction is associated with strengthened coupling among distally spaced CA1 neurons, suggesting an ACC-driven organization of a sparse code. This robust shift in physiology permits a support vector machine classifier to accurately determine memory age on the basis of the ACC-CA1 synchronization pattern. Our findings reveal that memory consolidation alters the dynamic coupling of the prefrontal-hippocampal circuit and results in a physiological signature of memory age.


Asunto(s)
Región CA1 Hipocampal/fisiología , Miedo/fisiología , Giro del Cíngulo/fisiología , Memoria a Largo Plazo/fisiología , Memoria/fisiología , Recuerdo Mental/fisiología , Neuronas/fisiología , Animales , Conducta Animal , Aprendizaje Automático , Masculino , Consolidación de la Memoria/fisiología , Ratones , Vías Nerviosas/fisiología , Máquina de Vectores de Soporte
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