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1.
Plant Physiol ; 193(3): 1758-1771, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37433052

RESUMO

Apiose is a unique branched-chain pentose found in plant glycosides and a key component of the cell wall polysaccharide pectin and other specialized metabolites. More than 1,200 plant-specialized metabolites contain apiose residues, represented by apiin, a distinctive flavone glycoside found in celery (Apium graveolens) and parsley (Petroselinum crispum) in the family Apiaceae. The physiological functions of apiin remain obscure, partly due to our lack of knowledge on apiosyltransferase during apiin biosynthesis. Here, we identified UGT94AX1 as an A. graveolens apiosyltransferase (AgApiT) responsible for catalyzing the last sugar modification step in apiin biosynthesis. AgApiT showed strict substrate specificity for the sugar donor, UDP-apiose, and moderate specificity for acceptor substrates, thereby producing various apiose-containing flavone glycosides in celery. Homology modeling of AgApiT with UDP-apiose, followed by site-directed mutagenesis experiments, identified unique Ile139, Phe140, and Leu356 residues in AgApiT, which are seemingly crucial for the recognition of UDP-apiose in the sugar donor pocket. Sequence comparison and molecular phylogenetic analysis of celery glycosyltransferases suggested that AgApiT is the sole apiosyltransferase-encoding gene in the celery genome. Identification of this plant apiosyltransferase gene will enhance our understanding of the physioecological functions of apiose and apiose-containing compounds.


Assuntos
Apium , Flavonas , Apium/genética , Glicosídeos , Filogenia
2.
J Autoimmun ; 136: 103027, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36996700

RESUMO

Primary biliary cholangitis (PBC) is a classic autoimmune disease due to the loss of tolerance to self-antigens. Bile acids (BA) reportedly play a major role in biliary inflammation and/or in the modulation of dysregulated immune responses in PBC. Several murine models have indicated that molecular mimicry plays a role in autoimmune cholangitis; however, they have all been limited by the relative failure to develop hepatic fibrosis. We hypothesized that species-specific differences in the BA composition between mice and humans were the primary reason for this limited pathology. Here, we aimed to study the impact of human-like hydrophobic BA composition on the development of autoimmune cholangitis and hepatic fibrosis. We took advantage of a unique construct, Cyp2c70/Cyp2a12 double knockout (DKO) mice, which have human-like BA composition, and immunized them with a well-defined mimic of the major mitochondrial autoantigen of PBC, namely 2-octynoic acid (2OA). 2OA-treated DKO mice were significantly exacerbated portal inflammation and bile duct damage with increased Th1 cytokines/chemokines at 8 weeks post-initial immunization. Most importantly, there was clear progression of hepatic fibrosis and increased expression of hepatic fibrosis-related genes. Interestingly, these mice demonstrated increased serum BA concentrations and decreased biliary BA concentrations; hepatic BA levels did not increase because of the upregulation of transporters responsible for the basolateral efflux of BA. Furthermore, cholangitis and hepatic fibrosis were more advanced at 24 weeks post-initial immunization. These results indicate that both the loss of tolerance and the effect of hydrophobic BA are essential for the progression of PBC.


Assuntos
Doenças Autoimunes , Colangite , Cirrose Hepática Biliar , Humanos , Animais , Camundongos , Ácidos e Sais Biliares , Cirrose Hepática , Inflamação , Autoantígenos , Modelos Animais de Doenças
3.
Mol Cell Biochem ; 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37902885

RESUMO

BACKGROUND & AIMS: Hepatic stellate cells (HSCs) play an essential role in liver fibrogenesis. The induction of cellular senescence has been reported to inhibit HSC activation. Previously, we demonstrated that CWHM12, a small molecule arginine-glycine-aspartic acid (RGD) peptidomimetic compound, inhibits HSC activation. This study investigated whether the inhibitory effects of CWHM12 on HSCs affected cellular senescence. METHODS: The immortalized human HSC lines, LX-2 and TWNT-1, were used to evaluate the effects of CWHM12 on cellular senescence via the disruption of RGD-mediated binding to integrins. RESULTS: CWHM12 induces cell cycle arrest, senescence-associated beta-galactosidase activity, acquisition of senescence-associated secretory phenotype (SASP), and expression of senescence-associated proteins in HSCs. Further experiments revealed that the phosphorylation of AKT and murine double minute 2 (MDM2) was involved in the effects of CWHM12, and the inhibition of AKT phosphorylation reversed these effects of CWHM12 on HSCs. CONCLUSIONS: Pharmacological inhibition of RGD-mediated integrin binding induces senescence in activated HSCs.

4.
Int J Mol Sci ; 24(23)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38069442

RESUMO

The flavonoid glycoside apiin (apigenin 7-O-[ß-D-apiosyl-(1→2)-ß-D-glucoside]) is abundant in apiaceous and asteraceous plants, including celery and parsley. Although several enzymes involved in apiin biosynthesis have been identified in celery, many of the enzymes in parsley (Petroselinum crispum) have not been identified. In this study, we identified parsley genes encoding the glucosyltransferase, PcGlcT, and the apiosyltransferase, PcApiT, that catalyze the glycosylation steps of apiin biosynthesis. Their substrate specificities showed that they were involved in the biosynthesis of some flavonoid 7-O-apiosylglucosides, including apiin. The expression profiles of PcGlcT and PcApiT were closely correlated with the accumulation of flavonoid 7-O-apiosylglucosides in parsley organs and developmental stages. These findings support the idea that PcGlcT and PcApiT are involved in the biosynthesis of flavonoid 7-O-apiosylglucosides in parsley. The identification of these genes will elucidate the physiological significance of apiin and the development of apiin production methods.


Assuntos
Apium , Glicosídeos Cardíacos , Glicosídeos/química , Petroselinum/química , Glicosiltransferases/genética , Flavonoides/química
5.
Am J Physiol Renal Physiol ; 321(6): F771-F784, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34719949

RESUMO

Homozygous mutations in SLC4A4, which encodes the electrogenic Na+/[Formula: see text] cotransporter (NBCe1), cause proximal renal tubular acidosis associated with extrarenal symptoms. Although 17` mutated sites in SLC4A4 have thus far been identified among patients with proximal renal tubular acidosis, the physiological significance of other nonsynonymous single-nucleotide variants (SNVs) remains largely undetermined. Here, we investigated the functional properties of SNVs in NBCe1. From the National Center for Biotechnology Information dbSNP database, we identified 13 SNVs that have not previously been characterized in the highly conserved, transmembrane domains of NBCe1-A. Immunocytochemical analysis revealed that the I551F variant was present predominantly in the cytoplasm in human embryonic kidney (HEK)-293 cells, whereas all other SNVs did not show as dramatic a change in subcellular distribution. Western blot analysis in HEK-293 cells demonstrated that the I551F variant showed impaired glycosylation and a 69% reduction in cell surface levels. To determine the role of I551 in more detail, we examined the significance of various artificial mutants in both nonpolarized HEK-293 cells and polarized Madin-Darby canine kidney cells, which indicated that only I551F substitution resulted in cytoplasmic retention. Moreover, functional analysis using Xenopus oocytes demonstrated that the I551F variant had a significantly reduced activity corresponding to 39% of that of the wild-type, whereas any other SNVs and artificial I551 mutants did not show significant changes in activity. Finally, immunofluorescence experiments in HEK-293 cells indicated that the I551F variant retained wild-type NBCe1-A in the cytoplasm. These data demonstrate that the I551F variant of NBCe1-A shows impaired transport activity predominantly through cytoplasmic retention and suggest that the variant can have a dominant negative effect by forming complexes with wild-type NBCe1-A.NEW & NOTEWORTHY Electrogenic Na+/[Formula: see text] cotransporter 1-A (NBCe1-A) in the proximal tubule regulates the acid/base balance and fluid volume homeostasis. From the National Center for Biotechnology Information dbSNP database, we identified the I551F variant of NBCe1-A, which showed reduced glycosylation, cell surface expression, and transport activity. We also found that the I551F variant can exert a dominant negative effect on wild-type NBCe1-A, suggesting its physiological significance.


Assuntos
Membrana Celular/metabolismo , Simportadores de Sódio-Bicarbonato/metabolismo , Animais , Bases de Dados Genéticas , Cães , Glicosilação , Células HEK293 , Humanos , Transporte de Íons , Células Madin Darby de Rim Canino , Oócitos , Polimorfismo de Nucleotídeo Único , Transporte Proteico , Simportadores de Sódio-Bicarbonato/genética , Xenopus laevis
6.
Chemistry ; 27(56): 13982-13990, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34405922

RESUMO

Despite recent extensive studies on mechanochromic luminescence (MCL), rational control over the magnitude of the emission-wavelength shift in response to mechanical stimuli remains challenging. In the present study, a two-component donor-acceptor approach has been applied to create a variety of organic MCL composites that exhibit remarkable emission-wavelength switching. Dibenzofuran-based bis(1-pyrenylmethyl)diamine and typical organic fluorophores have been employed as donor and acceptor dyes, respectively. Outstanding wide-range MCL with an emission-wavelength shift of over 300 nm has been achieved by mixing the diamine with 3,4,9,10-perylenetetracarboxylic diimide. Unprecedented two-step MCL in response to mechanical stimuli of different intensity has also been realized for a two-component mixture with 9,10-anthraquinone. Fluorescence microscopy observations at the single-particle level revealed that the segregation and mixing of the two-component dyes contribute to the stimuli-responsive emission-color switching of the MCL composites.

7.
Hepatol Res ; 51(1): 80-89, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33080094

RESUMO

AIM: The ursodeoxycholic acid response score (URS) can predict the biochemical response to 12 months of ursodeoxycholic acid (UDCA) treatment in patients with primary biliary cholangitis (PBC). We investigated the relationship between the URS and the histopathological features before and after UDCA treatment. METHODS: Patients with PBC (n = 126) were examined for the association between the probability of response (POR) to UDCA based on the URS formulas and clinicopathological features. Furthermore, 30 patients were examined for the association between the POR and pathological changes. RESULTS: The POR area under the receiver operating characteristic curve (AUROC) for predicting the biochemical response to UDCA was 0.861. The PORs of stage 1 in the Nakanuma system and grade 0 in the CK7 grading in hepatocytes were significantly higher than those of stage 3 and grade 3, respectively. The AUROCs for the prediction of stage ≥2, stage ≥3 and stage 4 in the Nakanuma system at pretreatment were 0.592, 0.710 and 0.817, respectively. The AUROCs for the prediction of grade ≥1, grade ≥2 and grade 3 in the CK7 hepatocyte grading were 0.741, 0.824 and 0.970, respectively. Furthermore, the AUROC for predicting the histological stage progression after UDCA treatment in the Scheuer classification and the Nakanuma system were 0.712 and 0.799, respectively. CONCLUSIONS: The URS not only predicts the biochemical response, but also reflects the Nakanuma system and the CK7 hepatocyte grading at pretreatment. This scoring system can identify an inadequate histological response to UDCA treatment in the Scheuer classification and the Nakanuma system.

8.
Phys Chem Chem Phys ; 23(16): 10130-10131, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33870395

RESUMO

Correction for 'Local structure of a highly concentrated NaClO4 aqueous solution-type electrolyte for sodium ion batteries' by Ryo Sakamoto et al., Phys. Chem. Chem. Phys., 2020, 22, 26452-26458, DOI: 10.1039/D0CP04376A.

9.
Phys Chem Chem Phys ; 22(45): 26452-26458, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33180893

RESUMO

Aqueous Na-ion batteries with highly concentrated NaClO4 aq. electrolytes are drawing attention as candidates for large-scale rechargeable batteries with a high safety level. However, the detailed mechanism by which the potential window in 17 m NaClO4 aq. electrolyte was expanded remains unclear. Therefore, we investigated the local structure around a Na+ ion or a ClO4- ion using X-ray diffraction combined with empirical potential structure refinement (EPSR) modelling and Raman spectroscopy. The results showed that in 17 m NaClO4 aq. electrolyte, most of the water molecules were coordinated to Na+ ions and few free water molecules were present. The 17 m NaClO4 aq. electrolyte could be interpreted as widening the potential window because almost all water molecules participated in hydration of the Na+ ions.

10.
J Epidemiol ; 28(6): 300-306, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29353865

RESUMO

BACKGROUND: Globally, few published studies have tracked the temporal trend of dioxin levels in the human body since 2000. This study describes the annual trend of dioxin levels in human breast milk in Japanese mothers from 1998 through 2015. METHODS: An observational study was conducted from 1998 through 2015. Participants were 1,194 healthy mothers following their first delivery who were recruited annually in Japan. Breast milk samples obtained from participants were analyzed using gas chromatography and mass spectrometry for dioxins, including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and coplanar polychlorinated biphenyls (PCBs). RESULTS: Mean age was 29.5 years, and 53% of participants were 20-25 years old. A declining trend in total dioxin levels was found, from a peak of 20.8 pg toxic equivalence (TEQ)/g fat in 1998 to 7.2 pg TEQ/g fat in 2014. Data from the last 5 years of the study indicated a plateau at minimal levels. In contrast, an increasing trend was found in the mean age of participants during the last 5 years. Although significantly higher dioxin levels were observed in samples from older participants, an upward trend in dioxin levels was not observed, indicating that dietary and environmental exposure to dioxins had greatly diminished in recent years. CONCLUSIONS: Dioxin levels in human breast milk may be approaching a minimum in recent years in Japan. The findings may contribute to global reference levels for environmental pollution of dioxins, which remains a problem for many developing countries.


Assuntos
Dioxinas/análise , Leite Humano/química , Adulto , Feminino , Seguimentos , Humanos , Japão , Adulto Jovem
11.
Pediatr Int ; 60(1): 19-22, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29095541

RESUMO

BACKGROUND: Although the incidence rates of Kawasaki disease (KD) in Japan have been determined in nationwide surveys, the cumulative incidence, that is, the proportion of those with a history of KD in the general population of 10-year-olds, is currently unknown. The aim of this study was therefore to assess the cumulative incidence of KD in Japan. METHODS: Using the age- and sex-specific incidence rate of KD in Japan from the results of the nationwide surveys, incidence probabilities, that is, the age-specific number of KD patients divided by the population used in the vital statistics, and cumulative proportions of those not affected by KD up to the end of 9 years of age, were calculated. The cumulative incidence was then defined as 1 minus the cumulative proportion. The observed age classes were 0, 1, 2, 3, 4, and 5-9 years. All data were calculated by sex. RESULTS: The cumulative incidence was 0.004833 for boys and 0.003474 for girls in 1991, but was 0.015284 and 0.012145 in 2014, respectively. According to these figures, 15.284 per 1,000 boys and 12.145 per 1,000 girls have been affected by KD by the age of 10 years. The birth-cohort cumulative incidences had similar trends. CONCLUSIONS: More than 10 persons in 1,000 have a history of KD at age 10 years in Japan.


Assuntos
Síndrome de Linfonodos Mucocutâneos/epidemiologia , Criança , Pré-Escolar , Feminino , Inquéritos Epidemiológicos , Humanos , Incidência , Lactente , Recém-Nascido , Japão/epidemiologia , Masculino
12.
Int Heart J ; 59(1): 233-236, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29375114

RESUMO

We experienced a 45-year-old Japanese man who was transferred to our hospital complaining of acute onset of pain and pallor in the right lower limb. Two years earlier, he had complained of repetitive pain at rest and pallor in the left third and fourth fingers. The physical exam and angiography demonstrated occlusion of finger arteries, however we could not reach final diagnosis. Acute arterial occlusive disease in the right lower limb was suspected. Transthoracic echocardiography demonstrated a gross tumor in the left atrium, which suggested left atrial myxoma. An emergency tumorectomy was successfully conducted. Pathologically, the fragile tumor and resultant thrombosis could have caused the patient's peripheral circulatory failure at least two years prior to this episode. A rigorous systemic survey is important even when the ischemic symptom is localized in peripheral circulation.


Assuntos
Dedos/irrigação sanguínea , Neoplasias Cardíacas/complicações , Isquemia/etiologia , Mixoma/complicações , Procedimentos Cirúrgicos Cardíacos , Ecocardiografia , Átrios do Coração , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirurgia , Humanos , Isquemia/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mixoma/diagnóstico , Mixoma/cirurgia , Tomografia Computadorizada por Raios X
13.
Clin Exp Nephrol ; 21(1): 16-26, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27089875

RESUMO

BACKGROUND: Podocytes play a central role in the formation of the glomerular filtration barrier in the kidney, and their dysfunction has been shown to result in proteinuria. In the present study, we sought to determine the cell-autonomous role of NF-κB, a proinflammatory signaling, within podocytes in proteinuric kidney disease. METHODS: Podocyte-specific IκBΔN transgenic (Pod-IκBΔN) mice, in which NF-κB was inhibited specifically in podocytes, were generated by the Cre-loxP technology, and their phenotype was compared with control mice in adriamycin-induced nephropathy. RESULTS: Pod-IκBΔN mice were phenotypically normal and did not exhibit proteinuria at the physiological condition. By the intravenous administration of adriamycin, overt proteinuria appeared in Pod-IκBΔN mice, as well as in control mice. However, of interest, the amount of proteinuria was significantly lower in adriamycin-injected Pod-IκBΔN mice (373 ± 122 mg albumin/g creatinine), compared with adriamycin-injected control mice (992 ± 395 mg albumin/g creatinine). Expression of podocyte-selective slit diaphragm-associated proteins, such as nephrin and synaptopodin, was markedly decreased by adriamycin injection in control mice, whereas the reduction was attenuated in Pod-IκBΔN mice. Adriamycin-induced reduction in synaptopodin expression was also seen in cultured podocytes derived from control mice, but not in those from Pod-IκBΔN mice. CONCLUSIONS: Because nephrin and synaptopodin are essential for the maintenance of the slit diaphragm in podocytes, these results suggest that proteinuria in adriamycin-induced nephropathy is caused by the reduction in expression of these proteins. The results also suggest that the NF-κB signalling in podocytes cell-autonomously contributes to proteinuria through the regulation of these proteins.


Assuntos
Albuminúria/prevenção & controle , Doxorrubicina , Nefropatias/prevenção & controle , NF-kappa B/metabolismo , Podócitos/metabolismo , Albuminúria/genética , Albuminúria/metabolismo , Albuminúria/patologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica , Genótipo , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Integrases/genética , Integrases/metabolismo , Nefropatias/genética , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Fenótipo , Podócitos/patologia , Transdução de Sinais
14.
J Am Soc Nephrol ; 27(5): 1379-88, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26471129

RESUMO

Endothelial cells participate in the pathophysiology of ischemic AKI by increasing the expression of cell adhesion molecules and by recruiting inflammatory cells. We previously showed that endothelial Krüppel-like factor 4 (Klf4) regulates vascular cell adhesion molecule 1 (Vcam1) expression and neointimal formation after carotid injury. In this study, we determined whether endothelial Klf4 is involved in ischemic AKI using endothelial Klf4 conditional knockout (Klf4 cKO) mice generated by breeding Tek-Cre mice and Klf4 floxed mice. Klf4 cKO mice were phenotypically normal before surgery. However, after renal ischemia-reperfusion injury, Klf4 cKO mice exhibited elevated serum levels of urea nitrogen and creatinine and aggravated renal histology compared with those of Klf4 floxed controls. Moreover, Klf4 cKO mice exhibited enhanced accumulation of neutrophils and lymphocytes and elevated expression of cell adhesion molecules, including Vcam1 and Icam1, in injured kidneys. Notably, statins ameliorated renal ischemia-reperfusion injury in control mice but not in Klf4 cKO mice. Mechanistic analyses in cultured endothelial cells revealed that statins increased KLF4 expression and that KLF4 mediated the suppressive effect of statins on TNF-α-induced VCAM1 expression by reducing NF-κB binding to the VCAM1 promoter. These results provide evidence that endothelial Klf4 is renoprotective and mediates statin-induced protection against ischemic AKI by regulating the expression of cell adhesion molecules and concomitant recruitment of inflammatory cells.


Assuntos
Injúria Renal Aguda/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Rim/irrigação sanguínea , Fatores de Transcrição Kruppel-Like/fisiologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Endotélio/metabolismo , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/biossíntese , Masculino , Camundongos
15.
Pediatr Cardiol ; 38(2): 375-380, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27878631

RESUMO

Few studies discuss the risk factors for acute cardiac lesions (within 30 days) resulting from Kawasaki disease (KD). We aimed to clarify the characteristics of patients with cardiac lesions within 30 days and determine the risk factors for acute cardiac lesion subtypes. Using the 23rd nationwide survey of KD in Japan, we analyzed data from patients with or without acute cardiac lesions resulting from KD (n = 31,380). We subdivided patients with acute cardiac lesions into three types: acute valvular lesions, coronary aneurysms, and giant coronary aneurysms (GCA), and calculated the odds ratios of potential risk factors for acute cardiac lesion subtypes. The prevalence of acute cardiac lesions was 8.6%, and these lesions were more prevalent among males than females (1.98:1). Male sex, age <1 year, and atypical definite cases predicted coronary artery lesions (CAL). The risk factors for valvular lesions differed from the risk factors for CALs, but GCA risk factors were similar to CAL risk factors: age <1 year, later presentation to hospital, atypical definite cases, and resistance to initial intravenous immunoglobulin (IVIG) therapy. Resistance to IVIG therapy was a significant risk factor for acute GCA. We found differences in cardiac lesion risk factors within 30 days of diagnosing KD between acute CAL and valvular lesions resulting from KD. In particular, pediatricians should consider atypical definite cases and resistance to initial IVIG when assessing the risk of acute-phase GCA.


Assuntos
Aneurisma Coronário/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Imunoglobulinas Intravenosas/uso terapêutico , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Criança , Pré-Escolar , Resistência a Medicamentos , Ecocardiografia , Feminino , Humanos , Lactente , Japão/epidemiologia , Modelos Logísticos , Masculino , Razão de Chances , Fatores de Risco , Distribuição por Sexo , Inquéritos e Questionários , Fatores de Tempo
16.
J Biol Chem ; 289(38): 26107-26118, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25100730

RESUMO

Kruppel-like factor 4 (KLF4) plays an important role in vascular diseases, including atherosclerosis and vascular injury. Although KLF4 is expressed in the heart in addition to vascular cells, the role of KLF4 in cardiac disease has not been fully determined. The goals of this study were to investigate the role of KLF4 in cardiac hypertrophy and to determine the underlying mechanisms. Cardiomyocyte-specific Klf4 knockout (CM Klf4 KO) mice were generated by the Cre/LoxP technique. Cardiac hypertrophy was induced by chronic infusion of the ß-adrenoreceptor agonist isoproterenol (ISO). Results showed that ISO-induced cardiac hypertrophy was enhanced in CM Klf4 KO mice compared with control mice. Accelerated cardiac hypertrophy in CM Klf4 KO mice was accompanied by the augmented cellular enlargement of cardiomyocytes as well as the exaggerated expression of fetal cardiac genes, including atrial natriuretic factor (Nppa). Additionally, induction of myocardin, a transcriptional cofactor regulating fetal cardiac genes, was enhanced in CM Klf4 KO mice. Interestingly, KLF4 regulated Nppa expression by modulating the expression and activity of myocardin, providing a mechanical basis for accelerated cardiac hypertrophy in CM Klf4 KO mice. Moreover, we showed that KLF4 mediated the antihypertrophic effect of trichostatin A, a histone deacetylase inhibitor, because ISO-induced cardiac hypertrophy in CM Klf4 KO mice was attenuated by olmesartan, an angiotensin II type 1 antagonist, but not by trichostatin A. These results provide novel evidence that KLF4 is a regulator of cardiac hypertrophy by modulating the expression and the activity of myocardin.


Assuntos
Cardiomegalia/metabolismo , Fatores de Transcrição Kruppel-Like/fisiologia , Proteínas Nucleares/metabolismo , Transativadores/metabolismo , Angiotensina II/fisiologia , Animais , Anti-Hipertensivos/farmacologia , Fator Natriurético Atrial , Cardiomegalia/induzido quimicamente , Linhagem Celular , Expressão Gênica , Regulação da Expressão Gênica , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Imidazóis/farmacologia , Isoproterenol , Fator 4 Semelhante a Kruppel , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/metabolismo , Miócitos Cardíacos/metabolismo , Peptídeo Natriurético Tipo C/genética , Peptídeo Natriurético Tipo C/metabolismo , Proteínas Nucleares/genética , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Tetrazóis/farmacologia , Transativadores/genética
17.
Nephron Exp Nephrol ; 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25592271

RESUMO

Background: The present study aimed at investigating the effect of a novel antioxidant, hydrogen (H2) gas, on the severity of contrast-induced acute kidney injury (CIAKI) in a rat model. Methods: CIAKI was induced in rats by intravenous injection of a contrast medium, Ioversol, in addition to reagents inhibiting prostaglandin and nitric oxide synthesis. During the injection of these reagents, the rats inhaled H2 gas or control gas. Results: One day after the injection, serum levels of urea nitrogen were significantly lower in H2 gas-inhaling CIAKI rats (17.6 ± 2.3 mg/dl) than those in control gas-treated CIAKI rats (36.0 ± 7.3 mg/dl), although they both were elevated as compared to untreated rats (14.9 ± 0.9 mg/dl). Consistently, creatinine clearance in H2 gas-treated CIAKI rats was higher than that in control gas-treated counterparts. Renal histological analysis revealed that the formation of proteinaceous casts and tubular necrosis was improved by H2 gas inhalation. Mechanistic analyses showed that inhalation of H2 gas significantly reduced renal cell apoptosis, expression of cleaved caspase 3, and expression of an oxidative stress marker, 8-hydroxydeoxyguanosine, in injured kidneys. Conclusion: Results suggest that H2 gas inhalation is effective in ameliorating the severity of CIAKI in rats by reducing renal cell apoptosis and oxidative stress. © 2015 S. Karger AG, Basel.

18.
J Biol Chem ; 287(31): 25706-14, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22679022

RESUMO

Hyperphosphatemia in chronic kidney disease is highly associated with vascular calcification. Previous studies have shown that high phosphate-induced phenotypic switching of vascular smooth muscle cells (SMCs) into osteogenic cells plays an important role in the calcification process. In the present study, we determined whether Krüppel-like factor 4 (Klf4) and phosphorylated Elk-1, transcriptional repressors of SMC differentiation marker genes activated by intimal atherogenic stimuli, contributed to this process. Rat aortic SMCs were cultured in the medium with normal (0.9 mmol/liter) or high (4.5 mmol/liter) phosphate concentration. Results showed that high phosphate concentration induced SMC calcification. Moreover, high phosphate decreased expression of SMC differentiation marker genes including smooth muscle α-actin and SM22α, whereas it increased expression of osteogenic genes, such as Runx2 and osteopontin. High phosphate also induced Klf4 expression, although it did not phosphorylate Elk-1. In response to high phosphate, Klf4 selectively bound to the promoter regions of SMC differentiation marker genes. Of importance, siRNA-mediated knockdown of Klf4 blunted high phosphate-induced suppression of SMC differentiation marker genes, as well as increases in expression of osteogenic genes and calcium deposition. Klf4 was also induced markedly in the calcified aorta of adenine-induced uremic rats. Results provide novel evidence that Klf4 mediates high phosphate-induced conversion of SMCs into osteogenic cells.


Assuntos
Fatores de Transcrição Kruppel-Like/fisiologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/fisiologia , Osteoblastos/metabolismo , Fosfatos/fisiologia , Actinas/genética , Actinas/metabolismo , Animais , Antígenos de Diferenciação/metabolismo , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Transdiferenciação Celular , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/metabolismo , Masculino , Fenótipo , Fosforilação , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Interferência de RNA , Ratos , Ratos Sprague-Dawley , Uremia/induzido quimicamente , Uremia/metabolismo , Uremia/patologia , Calcificação Vascular/induzido quimicamente , Calcificação Vascular/metabolismo , Calcificação Vascular/patologia , Proteínas Elk-1 do Domínio ets/metabolismo
19.
J Vasc Res ; 50(6): 512-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24216515

RESUMO

High phosphate-induced phenotypic switching of smooth muscle cells (SMCs) into osteogenic cells is critical for the formation of arterial medial calcification in chronic kidney disease. Because vascular calcification is also prevalent in type 2 diabetes, we examined whether glucose concentration affects high phosphate-induced SMC phenotypic switching and calcification. First, the formation of arterial medial calcification was compared among 4 groups: adenine-fed uremic rats, streptozotocin-injected hyperglycemic rats, adenine-fed and streptozotocin-injected uremic/hyperglycemic rats, and control rats. Calcification was obvious in uremic and uremic/hyperglycemic rats, whereas it was undetectable in the others. Aortic calcium contents were significantly elevated in uremic and uremic/hyperglycemic rats, but they were not different between the two groups. Moreover, hyperglycemia had no effects on the reduced expression of SMC differentiation markers including smooth muscle α-actin and SM22α and on the increased expression of osteogenic markers, such as Runx2, in uremic rats. Second, cultured SMCs were incubated in the medium with various concentrations of phosphate (0.9-4.5 mmol/l) and glucose (5-50 mmol/l), and calcium deposition was measured. Although high phosphate dose-dependently increased calcium contents, they were unaffected by glucose concentration. Results suggest that glucose concentration does not directly modulate high phosphate-induced SMC phenotypic switching and arterial medial calcification.


Assuntos
Doenças da Aorta/sangue , Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Esclerose Calcificante da Média de Monckeberg/sangue , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Túnica Média/metabolismo , Uremia/sangue , Adenosina , Animais , Doenças da Aorta/patologia , Biomarcadores/metabolismo , Cálcio/metabolismo , Células Cultivadas , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Masculino , Esclerose Calcificante da Média de Monckeberg/patologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Osteogênese , Fenótipo , Fosfatos/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Fatores de Tempo , Túnica Média/patologia , Uremia/induzido quimicamente , Uremia/patologia
20.
Intern Med ; 62(8): 1157-1166, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36070948

RESUMO

A 59-year-old woman presented to our hospital with liver dysfunction. Imaging revealed multiple lesions in the liver. The patient was diagnosed with peliosis hepatis using percutaneous and laparoscopic biopsies. However, her condition worsened with the appearance of new, obvious mass-forming lesions. Therefore, she underwent a second percutaneous biopsy of these lesions and was diagnosed with hepatic angiosarcoma. Her condition progressed rapidly, and she died two weeks after the diagnosis. Diagnosis of hepatic angiosarcoma in the early stages is difficult. It should be noted that hepatic angiosarcoma may be associated with the development of peliosis hepatis.


Assuntos
Hemangiossarcoma , Neoplasias Hepáticas , Peliose Hepática , Feminino , Humanos , Pessoa de Meia-Idade , Peliose Hepática/diagnóstico , Peliose Hepática/diagnóstico por imagem , Hemangiossarcoma/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/diagnóstico por imagem
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