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1.
FASEB J ; 34(2): 3379-3398, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31922312

RESUMO

Aquaporin-5 (AQP5) plays a role in breast cancer cell migration. This study aimed to identify AQP5-targeting miRNAs and examine their effects on breast cancer cell migration through exosome-mediated delivery. Bioinformatic analyses identified miR-1226-3p, miR-19a-3p, and miR-19b-3p as putative regulators of AQP5 mRNA. Immunoblotting revealed a decrease of AQP5 protein abundance when each of these miRNAs was transfected into human breast cancer MDA-MB-231 cells. Quantitative real-time PCR demonstrated the reduction of AQP5 mRNA expression by the transfection of miR-1226-3p and a luciferase reporter assay revealed the reduction of AQP5 translation after the transfection of miR-19b-3p in MDA-MB-231 cells. Consistently, the transfection of each miRNA impeded cell migration. Pathway enrichment analyses showed that these three miRNAs regulate target genes, which were predominantly enriched in the gap junction pathway. For the efficient delivery of AQP5-targeting miRNAs to breast cancer cells, exosomes expressing both miRNAs and a peptide targeting interleukin-4 receptor, which is highly expressed in breast cancer cells, were bioengineered and their inhibitory effects on AQP5 protein expression and cell migration were demonstrated in MDA-MB-231 cells. Taken together, AQP5-regulating miRNAs are identified, which could be exploited for the inhibition of breast cancer cell migration via the exosome-mediated delivery.


Assuntos
Neoplasias da Mama/metabolismo , Movimento Celular , Exossomos/metabolismo , MicroRNAs/metabolismo , Aquaporina 5/genética , Aquaporina 5/metabolismo , Feminino , Células HEK293 , Humanos , Subunidade alfa de Receptor de Interleucina-4/metabolismo , Células MCF-7 , MicroRNAs/genética , Oligopeptídeos/metabolismo
2.
FASEB J ; 33(6): 7301-7314, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30860872

RESUMO

Hypercholesterolemia is reported to increase reactive oxygen species (ROS) and to promote breast cancer progression. ROS play an important role in tumor biology, and xanthine oxidase (XO) is an enzyme that generates ROS. The effects of febuxostat (FBX), an XO inhibitor, on breast cancer cell migration under LDL stimulation in vitro and metastasis of breast cancer associated with hypercholesterolemia in vivo were studied. In vitro, FBX significantly inhibited LDL-induced ROS production and cell migration. Treatment of small interfering RNA against XO was consistent with the findings of FBX treatment. In vivo, a significant increase of tumor growth and pulmonary metastasis was observed in a xenograft mouse model with 4T1 cells on a high cholesterol diet (HCD), both of which were markedly inhibited by FBX or allopurinol treatment. Moreover, ERK represented the main target-signaling pathway that was affected by FBX treatment in a xenograft mouse model on an HCD evaluated by NanoString nCounter analysis. Consistently, MEK/ERK inhibitors directly decreased the LDL-induced cell migration in vitro. In conclusion, FBX mitigates breast cancer cell migration and pulmonary metastasis in the hyperlipidemic condition, associated with decreased ROS generation and MAPK phosphorylation. The inhibition of ERK pathways is likely to underlie the XO inhibitor-mediated suppression of breast cancer cell migration.-Oh, S.-H., Choi, S.-Y., Choi, H.-J., Ryu, H.-M., Kim, Y.-J., Jung, H.-Y., Cho, J.-H., Kim, C.-D., Park, S.-H., Kwon, T.-H., Kim, Y.-L. The emerging role of xanthine oxidase inhibition for suppression of breast cancer cell migration and metastasis associated with hypercholesterolemia.


Assuntos
Neoplasias da Mama/enzimologia , Hipercolesterolemia/complicações , Neoplasias Pulmonares/secundário , Proteínas de Neoplasias/antagonistas & inibidores , Xantina Oxidase/antagonistas & inibidores , Alopurinol/farmacologia , Alopurinol/uso terapêutico , Animais , Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Colesterol na Dieta/toxicidade , Progressão da Doença , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Febuxostat/farmacologia , Febuxostat/uso terapêutico , Feminino , Flavonoides/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/prevenção & controle , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Proteínas de Neoplasias/genética , RNA Interferente Pequeno/farmacologia , Distribuição Aleatória , Espécies Reativas de Oxigênio , Imagem com Lapso de Tempo , Xantina Oxidase/genética , Ensaios Antitumorais Modelo de Xenoenxerto
3.
J Am Soc Nephrol ; 29(11): 2658-2670, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30305310

RESUMO

BACKGROUND: The bile acid-activated receptors, including the membrane G protein-coupled receptor TGR5 and nuclear farnesoid X receptor (FXR), have roles in kidney diseases. In this study, we investigated the role of TGR5 in renal water handling and the underlying molecular mechanisms. METHODS: We used tubule suspensions of inner medullary collecting duct (IMCD) cells from rat kidneys to investigate the effect of TGR5 signaling on aquaporin-2 (AQP2) expression, and examined the in vivo effects of TGR5 in mice with lithium-induced nephrogenic diabetes insipidus (NDI) and Tgr5 knockout (Tgr5-/-) mice. RESULTS: Activation of TGR5 by lithocholic acid (LCA), an endogenous TGR5 ligand, or INT-777, a synthetic TGR5-specific agonist, induced AQP2 expression and intracellular trafficking in rat IMCD cells via a cAMP-protein kinase A signaling pathway. In mice with NDI, dietary supplementation with LCA markedly decreased urine output and increased urine osmolality, which was associated with significantly upregulated AQP2 expression in the kidney inner medulla. Supplementation with endogenous FXR agonist had no effect. In primary IMCD suspensions from lithium-treated rats, treatment with INT-767 (FXR and TGR5 dual agonist) or INT-777, but not INT-747 (FXR agonist), increased AQP2 expression. Tgr5-/- mice exhibited an attenuated ability to concentrate urine in response to dehydration, which was associated with decreased AQP2 expression in the kidney inner medulla. In lithium-treated Tgr5-/- mice, LCA treatment failed to prevent reduction of AQP2 expression. CONCLUSIONS: TGR5 stimulation increases renal AQP2 expression and improves impaired urinary concentration in lithium-induced NDI. TGR5 is thus involved in regulating water metabolism in the kidney.


Assuntos
Aquaporina 2/metabolismo , Túbulos Renais Coletores/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Água/metabolismo , Animais , Aquaporina 2/genética , Ácidos e Sais Biliares/farmacologia , Células Cultivadas , Ácido Quenodesoxicólico/análogos & derivados , Ácido Quenodesoxicólico/farmacologia , Ácidos Cólicos/farmacologia , Diabetes Insípido Nefrogênico/metabolismo , Homeostase , Túbulos Renais Coletores/efeitos dos fármacos , Ácido Litocólico/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/deficiência , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais
4.
Am J Physiol Renal Physiol ; 314(3): F329-F342, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29070573

RESUMO

Mineralocorticoids trigger a profibrotic process in the kidney. In mouse cortical collecting duct cells, the present study addressed two main questions: 1) what are microRNAs (miRNAs) and their target genes that are changed by aldosterone? and 2) what do miRNAs, in response to aldosterone, regulate regarding signaling pathways related to fibrosis? A microarray chip assay was done in cells in the absence or presence of aldosterone treatment (10-6 M; 3 days). The candidate miRNAs were identified by the criteria of >30% of fold change among the significantly changed miRNAs ( P < 0.05). Twenty-nine miRNAs were upregulated (>1.3-fold), and 27 miRNAs were downregulated (<0.7-fold). Putative target genes of identified miRNAs were associated with 74 Kyoto Encyclopedia of Genes and Genomes pathways. Among them, the wingless-related integration site (Wnt) signaling pathway was highly ranked, where 15 mature miRNAs were observed. These miRNAs were further analyzed by real-time quantitative PCR, and among them, miR-130b-3p, miR-34c-5p, and miR-146a-5p were selected. Through the identification of putative target genes of these three miRNAs, mRNA and protein expression of the Ca2+/calmodulin-dependent protein kinase type II ß-chain ( Camk2b) gene (a target gene of miR-34c-5p) were found to be increased significantly in aldosterone-treated cells, where fibronectin (FN) and α-smooth muscle actin were induced. When CaMKIIß small interfering RNA or the miR-34c-5p mimic was transfected, aldosterone-induced FN expression was significantly attenuated, along with reduced CaMKIIß protein expression. A luciferase reporter assay revealed a decrease of CaMKIIß translation in cells transfected with miRNA mimics of miR-34c-5p. In conclusion, aldosterone-induced downregulation of miR-34c-5p in the Wnt signaling pathway and a consequent increase of CaMKIIß expression are likely to be involved in aldosterone-induced fibrosis.


Assuntos
Aldosterona , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Nefropatias/enzimologia , Túbulos Renais Coletores/enzimologia , MicroRNAs/metabolismo , Actinas/metabolismo , Animais , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Linhagem Celular , Modelos Animais de Doenças , Fibronectinas/metabolismo , Fibrose , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Nefropatias/induzido quimicamente , Nefropatias/genética , Nefropatias/patologia , Túbulos Renais Coletores/patologia , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Transcriptoma , Via de Sinalização Wnt
5.
Am J Physiol Renal Physiol ; 311(6): F1294-F1307, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27733367

RESUMO

The carboxyl terminus of aquaporin-2 (AQP2c) undergoes posttranslational modifications, including phosphorylation and ubiquitination, in the process of regulating aquaporin-2 (AQP2) translocation and protein abundance. We aimed to identify novel proteins interacting with AQP2c. Recombinant AQP2c protein was made in Escherichia coli BL21 (DE3) cells by exploiting the pET32 TrxA fusion system. Lysates of rat kidney inner medullary collecting duct (IMCD) tubule suspensions interacted with rat AQP2c bound to Ni2+-resin were subjected to LC-MS/MS proteomic analysis. Potential interacting proteins were identified, including vacuolar protein sorting-associated protein 35 (Vps35). Coimmunoprecipitation assay demonstrated that Vps35 interacted with AQP2c. Immunohistochemistry of rat kidney revealed that AQP2 and Vps35 were partly colocalized at the intracellular vesicles in collecting duct cells. The role of Vps35 in AQP2 regulation induced by 1-deamino-8D-arginine vasopressin (dDAVP) was examined in mpkCCDc14 cells. Cell surface biotinylation assay demonstrated that dDAVP-induced apical translocation of AQP2 was significantly decreased under siRNA-mediated Vps35 knockdown. dDAVP-induced AQP2 upregulation was less prominent in the cells with Vps35 knockdown. Moreover, AQP2 protein abundance was decreased to a greater extent during the withdrawal period after dDAVP stimulation under Vps35 knockdown, which was significantly inhibited by chloroquine (a blocker of the lysosomal pathway) but not by MG132 (a proteasome inhibitor). Immunocytochemistry demonstrated that internalized AQP2 was more associated with lysosomal-associated membrane protein 1 (LAMP-1) in primary cultured IMCD cells under a Vps35 knockdown situation. Taken together, our results show that Vps35 interacts with AQP2c, and depletion of Vps35 is likely to be associated with decreased AQP2 trafficking and increased lysosomal degradation of AQP2 protein.


Assuntos
Aquaporina 2/metabolismo , Rim/metabolismo , Lisossomos/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Técnicas de Silenciamento de Genes , Túbulos Renais Coletores/metabolismo , Fosforilação , RNA Interferente Pequeno , Ratos , Espectrometria de Massas em Tandem , Proteínas de Transporte Vesicular/genética
6.
Am J Physiol Renal Physiol ; 310(11): F1317-27, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-26962105

RESUMO

In the kidney, metabolic processes are different among the cortex (COR), outer medulla (OM), and inner medulla (IM). Using matrix-assisted laser desorption/ionization (MALDI) and imaging mass spectrometry (IMS), we examined the change of metabolites in the COR, OM, and IM of the rat kidney after furosemide treatment compared with vehicle-treated controls. Osmotic minipumps were implanted in male Sprague-Dawley rats to deliver 12 mg·day(-1)·rat(-1) of furosemide. Vehicle-treated (n = 14) and furosemide-treated (furosemide rats, n = 15) rats in metabolic cages received a fixed amount of rat chow (15 g·220 g body wt(-1)·day(-1) for each rat) with free access to water intake for 6 days. At day 6, higher urine output (32 ± 4 vs. 9 ± 1 ml/day) and lower urine osmolality (546 ± 44 vs. 1,677 ± 104 mosmol/kgH2O) were observed in furosemide rats. Extracts of COR, OM, and IM were analyzed by ultraperformance liquid chromatography coupled with quadrupole time-of-flight (TOF) mass spectrometry, where multivariate analysis revealed significant differences between the two groups. Several metabolites, including acetylcarnitine, betaine, carnitine, choline, and glycerophosphorylcholine (GPC), were significantly changed. The changes of metabolites were further identified by MALDI-TOF/TOF and IMS. Their spatial distribution and relative quantitation in the kidneys were analyzed by IMS. Carnitine compounds were increased in COR and IM, whereas carnitine and acetylcarnitine were decreased in OM. Choline compounds were increased in COR and OM but decreased in IM from furosemide rats. Betaine and GPC were decreased in OM and IM. Taken together, MALDI-TOF/TOF and IMS successfully provide the spatial distribution and relative quantitation of metabolites in the kidney.


Assuntos
Diuréticos/farmacologia , Furosemida/farmacologia , Rim/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Ingestão de Líquidos/efeitos dos fármacos , Rim/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Micção/efeitos dos fármacos
7.
Am J Geriatr Psychiatry ; 24(2): 144-53, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26238231

RESUMO

OBJECTIVES: The present study investigated the characteristics of amnestic mild cognitive impairment (aMCI) in subjects with low brain amyloid-beta (Aß) burden. Furthermore, the relationships between amyloid-independent cognitive decline and serum lipid profiles, particularly apolipoprotein A1 (APOA1), were evaluated. DESIGN: Cross-sectional and longitudinal follow-up study. SETTING: University hospital dementia clinic. PARTICIPANTS: 28 aMCI and 35 cognitive normal (CN) elderly. MEASUREMENTS: The study measures included baseline assessments of the subjects' clinical characteristics, lipid profiles, and magnetic resonance imaging and (11)C-labelled Pittsburgh Compound B (PiB) positron emission tomography scans. Based on PiB retention at baseline, the aMCI subjects were divided into low Aß (aMCI-) and high Aß (aMCI+) subgroups. All aMCI subjects were followed up over a 1-year period. RESULTS: The aMCI- group had a longer duration of illness than did the aMCI+ group. None of the aMCI- subjects were diagnosed with Alzheimer disease (AD) dementia during the 1-year follow-up period, whereas 26.7% of aMCI+ subjects developed AD dementia. The aMCI- group also exhibited lower serum APOA1 levels compared with both the aMCI+ and CN groups. Additionally, lower serum APOA1 levels were associated with cognitive decline and brain atrophy independent of Aß deposition and vascular burden. CONCLUSIONS: Patients with aMCI- likely exhibit different clinical and pathophysiological characteristics than patients with aMCI+. Additionally, APOA1 may be an important contributor underlying amyloid-independent neurodegeneration.


Assuntos
Doença de Alzheimer/diagnóstico , Amnésia/sangue , Amiloide/metabolismo , Apolipoproteína A-I/sangue , Encéfalo/patologia , Disfunção Cognitiva/sangue , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina/administração & dosagem , Atrofia , Mapeamento Encefálico , Estudos Transversais , Progressão da Doença , Feminino , Seguimentos , Humanos , Modelos Lineares , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/administração & dosagem , Tiazóis/administração & dosagem
8.
Am J Geriatr Psychiatry ; 24(8): 604-612, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27311886

RESUMO

OBJECTIVES: Although many preclinical studies have suggested the possible linkage between dyslipidemia and cerebral amyloid deposition, the association between serum lipid measures and cerebral amyloid-beta (Aß) deposition in human brain is still poorly known. We aimed to investigate the association in cognitively normal (CN) elderly individuals. DESIGN: Cross-sectional study. SETTING: University hospital dementia clinic. PARTICIPANTS: 59 CN elderly. MEASUREMENTS: The study measures included comprehensive clinical and neuropsychological assessment based on the CERAD protocol, magnetic resonance imaging and (11)C-labelled Pittsburgh Compound B positron emission tomography scans, and quantification for serum lipid biomarkers. RESULTS: Multiple linear regression analyses showed that a higher serum triglycerides level was associated with heavier global cerebral Aß deposition even after controlling age, sex, and apolipoprotein E ε4 genotype. Serum apolipoprotein B also showed significant positive association with global cerebral Aß deposition, but the significance disappeared after controlling serum triglycerides level. No association was found between other lipid measures and global cerebral Aß deposition. CONCLUSIONS: The findings suggest that serum triglycerides are closely associated with cerebral amyloidosis, although population-based prospective studies are needed to provide further evidence of the causative effect of triglycerides on cerebral amyloidosis.


Assuntos
Envelhecimento/sangue , Amiloidose/diagnóstico por imagem , Encéfalo/patologia , Triglicerídeos/sangue , Idoso , Idoso de 80 Anos ou mais , Peptídeos beta-Amiloides/metabolismo , Amiloidose/sangue , Apolipoproteína E4/genética , Apolipoproteínas B/sangue , Biomarcadores/sangue , Encéfalo/diagnóstico por imagem , Cognição , Estudos Transversais , Feminino , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons , República da Coreia
9.
Dement Geriatr Cogn Disord ; 42(3-4): 135-145, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27643797

RESUMO

AIMS: The aims of this study were to investigate the frequency of various depressive syndromes in elderly individuals with no cognitive impairment (NC), mild cognitive impairment (MCI), and Alzheimer's disease dementia (AD) in a memory clinic setting, and then to test whether severe and milder forms of depressive syndromes are differentially associated with the cognitive groups. METHODS: For 216 NC, 478 MCI, and 316 AD subjects, we investigated the frequency of depressive syndromes, defined by three different categories: major and minor depressive disorder (MaDD and MiDD) according to the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, as well as depression according to the National Institute of Mental Health provisional diagnostic criteria for depression in Alzheimer's disease (NIMH-dAD). RESULTS: The frequency of MaDD did not show any significant difference among NC, MCI, and AD. In contrast, the frequencies of MiDD and NIMH-dAD were higher than those of MaDD and showed significant group differences with a gradual increase from NC to AD. CONCLUSION: The findings suggest that the degenerative process of Alzheimer's disease contributes to the occurrence of mild depressive conditions, but not to severe depression.


Assuntos
Doença de Alzheimer/epidemiologia , Disfunção Cognitiva/epidemiologia , Transtorno Depressivo Maior/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Disfunção Cognitiva/psicologia , Comorbidade , Transtorno Depressivo/epidemiologia , Transtorno Depressivo/psicologia , Transtorno Depressivo Maior/psicologia , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Memória , Prevalência , República da Coreia/epidemiologia
10.
Am J Physiol Renal Physiol ; 308(7): F737-48, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25651562

RESUMO

Kidney collecting duct cells are continuously exposed to the changes of extracellular pH (pHe). We aimed to study the effects of altered pHe on desmopressin (dDAVP)-induced phosphorylation (Ser(256), Ser(261), Ser(264), and Ser(269)) and apical targeting of aquaporin-2 (AQP2) in rat kidney inner medullary collecting duct (IMCD) cells. When freshly prepared IMCD tubule suspensions exposed to HEPES buffer with pH 5.4, 6.4, 7.4, or 8.4 for 1 h were stimulated with dDAVP (10(-10) M, 3 min), AQP2 phosphorylation at Ser(256), Ser(264), and Ser(269) was significantly attenuated under acidic conditions. Next, IMCD cells primary cultured in transwell chambers were exposed to a transepithelial pH gradient for 1 h (apical pH 6.4, 7.4, or 8.4 vs. basolateral pH 7.4 and vice versa). Immunocytochemistry and cell surface biotinylation assay revealed that exposure to either apical pH 6.4 or basolateral pH 6.4 for 1 h was associated with decreased dDAVP (10(-9) M, 15 min, basolateral)-induced apical targeting of AQP2 and surface expression of AQP2. Fluorescence resonance energy transfer analysis revealed that the dDAVP (10(-9) M)-induced increase of PKA activity was significantly attenuated when LLC-PK1 cells were exposed to pHe 6.4 compared with pHe 7.4 and 8.4. In contrast, forskolin (10(-7) M)-induced PKA activation and dDAVP (10(-9) M)-induced increases of intracellular Ca(2+) were not affected. Taken together, dDAVP-induced phosphorylation and apical targeting of AQP2 are attenuated in IMCD cells under acidic pHe, likely via an inhibition of vasopressin V2 receptor-G protein-cAMP-PKA actions.


Assuntos
Aquaporina 2/metabolismo , Membrana Celular/efeitos dos fármacos , Túbulos Renais Coletores/metabolismo , Animais , Aquaporina 2/efeitos dos fármacos , Linhagem Celular , Membrana Celular/metabolismo , Desamino Arginina Vasopressina/farmacologia , Espaço Extracelular/metabolismo , Concentração de Íons de Hidrogênio , Espaço Intracelular/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Células LLC-PK1 , Masculino , Fosforilação/fisiologia , Transporte Proteico/efeitos dos fármacos , Ratos Sprague-Dawley , Fármacos Renais/farmacologia , Suínos
11.
Am J Physiol Renal Physiol ; 309(5): F474-83, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26109089

RESUMO

Because cyclophosphamide-induced hyponatremia was reported to occur without changes in plasma vasopressin in a patient with central diabetes insipidus, we hypothesized that cyclophosphamide or its active metabolite, 4-hydroperoxycyclophosphamide (4-HC), may directly dysregulate the expression of water channels or sodium transporters in the kidney. To investigate whether intrarenal mechanisms for urinary concentration are activated in vivo and in vitro by treatment with cyclophosphamide and 4-HC, respectively, we used water-loaded male Sprague-Dawley rats, primary cultured inner medullary collecting duct (IMCD) cells, and IMCD suspensions prepared from male Sprague-Dawley rats. In cyclophosphamide-treated rats, significant increases in renal expression of aquaporin-2 (AQP2) and Na-K-2Cl cotransporter type 2 (NKCC2) were shown by immunoblot analysis and immunohistochemistry. Apical translocation of AQP2 was also demonstrated by quantitative immunocytochemistry. In both rat kidney and primary cultured IMCD cells, significant increases in AQP2 and vasopressin receptor type 2 (V2R) mRNA expression were demonstrated by real-time quantitative PCR analysis. Confocal laser-scanning microscopy revealed that apical translocation of AQP2 was remarkably increased when primary cultured IMCD cells were treated with 4-HC in the absence of vasopressin stimulation. Moreover, AQP2 upregulation and cAMP accumulation in response to 4-HC were significantly reduced by tolvaptan cotreatment in primary cultured IMCD cells and IMCD suspensions, respectively. We demonstrated that, in the rat kidney, cyclophosphamide may activate V2R and induce upregulation of AQP2 in the absence of vasopressin stimulation, suggesting the possibility of drug-induced nephrogenic syndrome of inappropriate antidiuresis (NSIAD).


Assuntos
Aquaporina 2/metabolismo , Ciclofosfamida/análogos & derivados , Ciclofosfamida/farmacologia , Túbulos Renais Coletores/efeitos dos fármacos , Rim/efeitos dos fármacos , Vasopressinas/metabolismo , Animais , Células Cultivadas , Rim/metabolismo , Túbulos Renais Coletores/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Membro 1 da Família 12 de Carreador de Soluto/metabolismo
12.
Am J Physiol Renal Physiol ; 308(5): F473-86, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25520007

RESUMO

Aquaporin-2 (AQP2) mediates arginine vasopressin (AVP)-induced water reabsorption in the kidney collecting duct. AVP regulates AQP2 expression primarily via Gsα/cAMP/PKA signaling. Tankyrase, a member of the poly(ADP-ribose) polymerase family, is known to mediate Wnt/ß-catenin signaling-induced gene expression. We examined whether tankyrase plays a role in AVP-induced AQP2 regulation via ADP-ribosylation of G protein-α (Gα) and/or ß-catenin-mediated transcription of AQP2. RT-PCR and immunoblotting analysis revealed the mRNA and protein expression of tankyrase in mouse kidney and mouse collecting duct mpkCCDc14 cells. dDAVP-induced AQP2 upregulation was attenuated in mpkCCDc14 cells under the tankyrase inhibition by XAV939 treatment or small interfering (si) RNA knockdown. Fluorescence resonance energy transfer image analysis, however, revealed that XAV939 treatment did not affect dDAVP- or forskolin-induced PKA activation. Inhibition of tankyrase decreased dDAVP-induced phosphorylation of ß-catenin (S552) and nuclear translocation of phospho-ß-catenin. siRNA-mediated knockdown of ß-catenin decreased forskolin-induced AQP2 transcription and dDAVP-induced AQP2 expression. Moreover, inhibition of phosphoinositide 3-kinase/Akt, which was associated with decreased nuclear translocation of ß-catenin, diminished dDAVP-induced AQP2 upregulation, further indicating that ß-catenin mediates AQP2 expression. Taken together, tankyrase plays a role in AVP-induced AQP2 regulation, which is likely via ß-catenin-mediated transcription of AQP2, but not ADP-ribosylation of Gα. The results provide novel insights into vasopressin-mediated urine concentration and homeostasis of body water metabolism.


Assuntos
Aquaporina 2/metabolismo , Túbulos Renais Coletores/enzimologia , Tanquirases/metabolismo , beta Catenina/metabolismo , Adenosina Difosfato Ribose/metabolismo , Animais , Linhagem Celular , Colforsina , AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Subunidades alfa de Proteínas de Ligação ao GTP/metabolismo , Técnicas de Silenciamento de Genes , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Homeostase , Imuno-Histoquímica , Masculino , Camundongos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Regulação para Cima , Vasopressinas , Água/metabolismo
13.
J Geriatr Psychiatry Neurol ; 28(3): 184-92, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25736510

RESUMO

BACKGROUND/OBJECTIVES: We aimed to elucidate the functional neuroanatomical correlates of Frontal Assessment Battery (FAB) performances by applying [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) to a large population of patients with Alzheimer disease (AD). METHODS: The FAB was administered to 177 patients with AD, and regional cerebral glucose metabolism (rCMglc) was measured by FDG-PET scan. Correlations between FAB scores and rCMglc were explored using both region-of-interest-based (ROI-based) and voxel-based approaches. RESULTS: The ROI-based analysis showed that FAB scores correlated with the rCMglc of the dorsolateral prefrontal cortices. Voxel-based approach revealed significant positive correlations between FAB scores and rCMglc which were in various cortical regions including the temporal and parietal cortices as well as frontal regions, independent of age, gender, and education. After controlling the effect of global disease severity with Mini-Mental State Examination score, significant positive correlation was found only in the bilateral prefrontal regions. CONCLUSIONS: Although FAB scores are influenced by temporoparietal dysfunction due to the overall progression of AD, it likely reflects prefrontal dysfunction specifically regardless of global cognitive state or disease severity in patients with AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/fisiopatologia , Encéfalo/metabolismo , Fluordesoxiglucose F18 , Glucose/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Encéfalo/diagnóstico por imagem , Progressão da Doença , Feminino , Humanos , Masculino , Testes Neuropsicológicos
14.
J Korean Med Sci ; 30(6): 779-87, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26028932

RESUMO

We compared the predictive ability of the various neuroimaging tools and determined the most cost-effective, non-invasive Alzheimer's disease (AD) prediction model in mild cognitive impairment (MCI) individuals. Thirty-two MCI subjects were evaluated at baseline with [(18)F]-fluorodeoxyglucose positron emission tomography (FDG-PET), MRI, diffusion tensor imaging (DTI), and neuropsychological tests, and then followed up for 2 yr. After a follow up period, 12 MCI subjects converted to AD (MCIc) and 20 did not (MCInc). Of the voxel-based statistical comparisons of baseline neuroimaging data, the MCIc showed reduced cerebral glucose metabolism (CMgl) in the temporo-parietal, posterior cingulate, precuneus, and frontal regions, and gray matter (GM) density in multiple cortical areas including the frontal, temporal and parietal regions compared to the MCInc, whereas regional fractional anisotropy derived from DTI were not significantly different between the two groups. The MCIc also had lower Mini-Mental State Examination (MMSE) score than the MCInc. Through a series of model selection steps, the MMSE combined with CMgl model was selected as a final model (classification accuracy 93.8%). In conclusion, the combination of MMSE with regional CMgl measurement based on FDG-PET is probably the most efficient, non-invasive method to predict AD in MCI individuals after a two-year follow-up period.


Assuntos
Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico , Glucose/metabolismo , Substância Cinzenta/patologia , Substância Branca/patologia , Idoso , Doença de Alzheimer/complicações , Atrofia/patologia , Biomarcadores/sangue , Disfunção Cognitiva/etiologia , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Neuroimagem/métodos , Tomografia por Emissão de Pósitrons/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença
15.
Angew Chem Int Ed Engl ; 54(41): 12020-4, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26315561

RESUMO

Targeted therapy based on protein-drug conjugates has attracted significant attention owing to its high efficacy and low side effects. However, efficient and stable drug conjugation to a protein binder remains a challenge. Herein, a chemoenzymatic method to generate highly stable and homogenous drug conjugates with high efficiency is presented. The approach comprises the insertion of the CaaX sequence at the C-terminal end of the protein binder, prenylation using farnesyltransferase, and drug conjugation through an oxime ligation reaction. MMAF and an EGFR-specific repebody are used as the antitumor agent and protein binder, respectively. The method enables the precisely controlled synthesis of repebody-drug conjugates with high yield and homogeneity. The utility of this approach is illustrated by the notable stability of the repebody-drug conjugates in human plasma, negligible off-target effects, and a remarkable antitumor activity in vivo. The present method can be widely used for generating highly homogeneous and stable PDCs for targeted therapy.


Assuntos
Antineoplásicos/química , Receptores ErbB/metabolismo , Oligopeptídeos/química , Oximas/química , Proteínas/química , Animais , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/química , Farnesiltranstransferase/metabolismo , Humanos , Camundongos Nus , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Oligopeptídeos/metabolismo , Oligopeptídeos/uso terapêutico , Oximas/metabolismo , Ligação Proteica , Prenilação de Proteína , Proteínas/metabolismo , Proteínas/uso terapêutico
16.
Int Psychogeriatr ; 26(11): 1897-904, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25075438

RESUMO

BACKGROUND: This study aimed to investigate the influences of age, education, and gender on the two total scores (TS-I and TS-II) of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological assessment battery (CERAD-NP) and to provide normative information based on an analysis for a large number of elderly persons with a wide range of educational levels. METHODS: In the study, 1,987 community-dwelling healthy volunteers (620 males and 1,367 females; 50-90 years of age; and zero to 25 years of education) were included. People with serious neurological, medical, and psychiatric disorders (including dementia) were excluded. All participants underwent the CERAD-NP assessment. TS-I was generated by summing raw scores from the CERAD-NP subtests, excluding Mini-Mental State Examination and Constructional Praxis (CP) recall subtests. TS-II was calculated by adding CP recall score to TS-I. RESULTS: Both TS-I and TS-II were significantly influenced by demographic variables. Education accounted for the greatest proportion of score variance. Interaction effect between age and gender was found. Based on the results obtained, normative data of the CERAD-NP total scores were stratified by age (six overlapping tables), education (four strata), and gender. CONCLUSIONS: The normative information will be very useful for better interpretation of the CERAD-NP total scores in various clinical and research settings and for comparing individuals' performance of the battery across countries.


Assuntos
Doença de Alzheimer/diagnóstico , Testes Neuropsicológicos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/normas , Testes Neuropsicológicos/estatística & dados numéricos , Reprodutibilidade dos Testes , Fatores Sexuais
17.
Respir Med Case Rep ; 48: 101990, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38332845

RESUMO

Pulmonary interstitial glycogenosis (PIG) is known to be associated with a wide variety of congenital conditions, though the extent to which PIG contributes to clinical presentation and outcomes in infants remains controversial. We describe two cases of infants with congenital anomalies and respiratory distress at birth who were diagnosed with PIG with differing clinical courses and response to methylprednisolone therapy. These cases highlight the importance of improved recognition of PIG and uncertainties about which patients may benefit from treatment.

18.
Front Neurosci ; 18: 1368641, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646607

RESUMO

Noise-vocoded speech has long been used to investigate how acoustic cues affect speech understanding. Studies indicate that reducing the number of spectral channel bands diminishes speech intelligibility. Despite previous studies examining the channel band effect using earlier event-related potential (ERP) components, such as P1, N1, and P2, a clear consensus or understanding remains elusive. Given our hypothesis that spectral degradation affects higher-order processing of speech understanding beyond mere perception, we aimed to objectively measure differences in higher-order abilities to discriminate or interpret meaning. Using an oddball paradigm with speech stimuli, we examined how neural signals correlate with the evaluation of speech stimuli based on the number of channel bands measuring N2 and P3b components. In 20 young participants with normal hearing, we measured speech intelligibility and N2 and P3b responses using a one-syllable task paradigm with animal and non-animal stimuli across four vocoder conditions with 4, 8, 16, or 32 channel bands. Behavioral data from word repetition clearly affected the number of channel bands, and all pairs were significantly different (p < 0.001). We also observed significant effects of the number of channels on the peak amplitude [F(2.006, 38.117) = 9.077, p < 0.001] and peak latency [F(3, 57) = 26.642, p < 0.001] of the N2 component. Similarly, the P3b component showed significant main effects of the number of channel bands on the peak amplitude [F(2.231, 42.391) = 13.045, p < 0.001] and peak latency [F(3, 57) = 2.968, p = 0.039]. In summary, our findings provide compelling evidence that spectral channel bands profoundly influence cortical speech processing, as reflected in the N2 and P3b components, a higher-order cognitive process. We conclude that spectrally degraded one-syllable speech primarily affects cortical responses during semantic integration.

19.
eNeuro ; 11(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38811162

RESUMO

This study compared the impact of spectral and temporal degradation on vocoded speech recognition between early-blind and sighted subjects. The participants included 25 early-blind subjects (30.32 ± 4.88 years; male:female, 14:11) and 25 age- and sex-matched sighted subjects. Tests included monosyllable recognition in noise at various signal-to-noise ratios (-18 to -4 dB), matrix sentence-in-noise recognition, and vocoded speech recognition with different numbers of channels (4, 8, 16, and 32) and temporal envelope cutoff frequencies (50 vs 500 Hz). Cortical-evoked potentials (N2 and P3b) were measured in response to spectrally and temporally degraded stimuli. The early-blind subjects displayed superior monosyllable and sentence recognition than sighted subjects (all p < 0.01). In the vocoded speech recognition test, a three-way repeated-measure analysis of variance (two groups × four channels × two cutoff frequencies) revealed significant main effects of group, channel, and cutoff frequency (all p < 0.001). Early-blind subjects showed increased sensitivity to spectral degradation for speech recognition, evident in the significant interaction between group and channel (p = 0.007). N2 responses in early-blind subjects exhibited shorter latency and greater amplitude in the 8-channel (p = 0.022 and 0.034, respectively) and shorter latency in the 16-channel (p = 0.049) compared with sighted subjects. In conclusion, early-blind subjects demonstrated speech recognition advantages over sighted subjects, even in the presence of spectral and temporal degradation. Spectral degradation had a greater impact on speech recognition in early-blind subjects, while the effect of temporal degradation was similar in both groups.


Assuntos
Cegueira , Percepção da Fala , Humanos , Masculino , Feminino , Percepção da Fala/fisiologia , Adulto , Cegueira/fisiopatologia , Adulto Jovem , Eletroencefalografia/métodos , Estimulação Acústica , Reconhecimento Psicológico/fisiologia , Potenciais Evocados Auditivos/fisiologia
20.
J Proteome Res ; 11(7): 3816-28, 2012 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-22686594

RESUMO

To investigate the effects of changes in extracellular osmolality on the function of kidney collecting duct cells, particularly on water and sodium reabsorption in the conditions of diuresis and antidiuresis, we generated transcriptome and metabolome profiles of primary cultured inner medullary collecting duct (IMCD) cells. They were grown in hyperosmolar culture medium (640 mOsm) for 4 days and then exposed to either reduced (300 mOsm) or same osmolality for 1 or 2 days more. Integrated analysis of the transcriptome and metabolome revealed that decreased extracellular osmolality was associated with decreased levels of organic osmolytes, glucose, intermediates of citric acid cycle, and branched-chain amino acids (BCAA) in IMCD cells, along with significantly decreased gene expression and protein abundance of P-type transporters (ATP1B1), ABC transporters (ABCC5 and ABCG1), and insulin signaling pathways (IRS2). Quantitative real-time RT-PCR and semiquantitative immunoblotting confirmed the changes of transcript levels of differentially expressed genes and protein levels. Taken together, integrated analysis of omics data demonstrated that water and sodium reabsorption could be reduced by decreased extracellular osmolality per se, through decreased levels of ABC transporters and IRS2, which play a potential role in the transport of organic osmolytes, BCAA, glucose, and trafficking of epithelial sodium channel.


Assuntos
Túbulos Renais Coletores/metabolismo , Metaboloma , Transcriptoma , Animais , Células Cultivadas , Análise por Conglomerados , Meios de Cultura , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Túbulos Renais Coletores/citologia , Túbulos Renais Coletores/fisiologia , Espectroscopia de Ressonância Magnética , Masculino , Redes e Vias Metabólicas , Análise Multivariada , Concentração Osmolar , Reconhecimento Automatizado de Padrão , Análise de Componente Principal , Proteoma/genética , Proteoma/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Tolerância ao Sal , Estatísticas não Paramétricas
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