RESUMEN
BACKGROUND AND AIM: The present study aimed to investigate whether the mitochondrial KATP channel contributes to angiotensin II (Ang II)-induced vascular dysfunction, the development of hypertension, and atherosclerosis. METHODS AND RESULTS: ApoE (-/-) mice fed a high-fat diet were chronically infused with Ang II for eight weeks and concomitantly treated with losartan (ARB), apocynin, or 5-hydroxy decanoate (5-HD), or 3-methyladenine (3-MA). Systolic blood pressure was measured, and pathological changes of aortic or liver tissue were observed. Nitric oxide (NO), superoxide dismutase 2 (SOD2) levels and vasorelaxation rate were measured, and protein and mRNA expressions were examined by western blot and RT-PCR. Ang II-induced development of hypertension was suppressed not only by ARB, and apocynin but also by 5-HD or 3-MA. Ang II infusion decreased aortic NO production and relaxation, as well as SOD2 activity in liver, which were improved by all treatments. In addition, Ang II-induced activation of autophagy was suppressed by 5-HD in aortic tissue, furthermore, Ang II increases the atherosclerotic index in plasma and exacerbates the development of atherosclerosis by increases of fat deposition in the aorta and liver. Lipid metabolism-related mRNA expressions (LXR-α, LDLR, SRBI, Acca, and FASN) were changed by Ang II. Similarly, not only ARB, and apocynin, but also 5-HD and 3-MA suppressed Ang II-induced these changes. CONCLUSIONS: Our present findings evidence that mitochondrial KATP channel-mediated autophagy contributes to Ang II-induced vascular dysfunction, development of hypertension, and atherosclerosis.
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Angiotensina II , Aterosclerosis , Autofagia , Hipertensión , Óxido Nítrico , Superóxido Dismutasa , Animales , Autofagia/efectos de los fármacos , Masculino , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/genética , Hipertensión/fisiopatología , Hipertensión/inducido químicamente , Hipertensión/metabolismo , Hipertensión/patología , Óxido Nítrico/metabolismo , Aterosclerosis/inducido químicamente , Aterosclerosis/patología , Aterosclerosis/metabolismo , Aterosclerosis/genética , Aterosclerosis/fisiopatología , Ratones Noqueados para ApoE , Ratones Endogámicos C57BL , Aorta/efectos de los fármacos , Aorta/patología , Aorta/metabolismo , Aorta/fisiopatología , Presión Sanguínea/efectos de los fármacos , Ratones , Modelos Animales de Enfermedad , Hígado/metabolismo , Hígado/patología , Hígado/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Dieta Alta en Grasa , Canales de PotasioRESUMEN
Glucotoxicity, impaired insulin secretion, suppression of insulin gene expression, and apoptosis, in pancreatic ß-cells caused by chronic hyperglycemia is a key component of the pathogenesis of type 2 diabetes. Recently, it has been reported that rare sugar d-allulose has antihyperglycemic and antihyperlipidemic effects in diabetic rats. However, the direct effects of rare sugars including d-allulose on pancreatic ß-cell function are unclear. In this study, we investigated whether chronic exposure to ketohexoses causes glucotoxicity, suppression of insulin gene expression, and apoptosis, in INS-1 rat pancreatic insulinoma cells. d-Fructose, d-tagatose, l-allulose, and l-sorbose treatment for 1-week reduced insulin gene expression, whereas d-allulose, d-sorbose, l-fructose, and l-tagatose did not. All ketohexoses were transported into INS-1 cells, but were not metabolized. In addition, the ketohexoses did not induce apoptosis and did not affect glucose metabolism. These results suggest that long-term administration of d-allulose, d-sorbose, l-fructose, and l-tagatose does not affect pancreatic ß-cell function.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Insulinoma , Neoplasias Pancreáticas , Ratas , Animales , Sorbosa , Fructosa , Insulina/metabolismo , Azúcares , Glucosa/metabolismoRESUMEN
Glucagon-like peptide-1 receptor agonist (GLP-1RA) has been clinically proven to protect endothelial function. Previously, we demonstrated that endothelial NO synthase (eNOS) was activated by high-density lipoprotein (HDL) via its scavenger receptor of the B class/human homologue of SR-BI, CD36 and LIMPII analogous-1(hSR-BI/CLA-1). Here, we investigated the effect of GLP-1RA and exendin-4 on the expression of hSR-BI/CLA-1 in HUVECs. Our results confirmed that GLP-1R was expressed in HUVECs by PCR and exendin-4 significantly enhanced HDL-induced eNOS activation. Next, exendin-4 increased the expression of hSR-BI/CLA-1 and a blockade of GLP-1R cancelled this effect. Further, the hSR-BI/CLA-1 transcriptional activity was enhanced by exendin-4, which was diminished by the inhibition of AMPK or dominant-negative AMPK-α-subunit. Moreover, AMPK was phosphorylated by the activation of GLP-1R. Next, ChIP assay demonstrated that exendin-4 increased the FoxO1-binding in the hSR-BI/CLA-1 promoter by upregulation of FoxO1. Mutation of FoxO1-binding or silencing of FoxO1 cancelled the effect of exendin-4 on hSR-BI/CLA-1 expression. Exendin-4 reduced FoxO1 phosphorylation and induced its nuclear accumulation, while this effect was altered by the blocking of GLP-1R or inhibition of AMPK pathway. In summary, our results proved that exendin-4 increased hSR-BI/CLA-1 expression via the AMPK/FoxO1 pathway to activate eNOS, providing a basic mechanism underlining the protective effect of GLP-1RA on endothelial function.
RESUMEN
BACKGROUND: Signal transduction of Angiotensin II (Ang II) induced autophagy and its role in Ang II-induced dysfunction of HUVECs are still unclear. METHODS: HUVECs are stimulated with different doses of Ang II (10-9-10-5 mol/L) for different time (6-48 hours). Autophagy-related protein markers: LC3, Beclin-1 and SQSTM1/p62 are measured by western blot. RESULTS: Incubation with Ang II increases autophagic flux (Beclin-1, autophagosomes formation, and degradation of SQSTM1/p62, LC3-I). Increased autophagic levels are inhibited by pretreatment with Ang II type 1 receptor (AT1) blocker (Candesartan), NADPH Oxidase inhibitor (apocycin), mitochondrial KATP channels inhibitor (5-hydroxydecanoate, 5HD). 3-Methyladenine (inhibitors of autophagy) and rapamycin (activator of autophagy) respectively inhibits or activates Ang II-induced autophagy levels. Ang II decreases phosphorylation of endothelial nitric oxide synthase (eNOS) and NO production in HUVECs. L-NAME (NOS inhibitor) totally mimics the actions of Ang II on eNOS, NO production and autophagy levels. Rapamycin further decreases NO production combined with Ang II. Silence Atg5 completely reverses Ang II-activated autophagy levels. CONCLUSIONS: Our results demonstrate that Ang II stimulation increases autophagy levels via AT1 receptor, NADPH oxidase, mitochondrial KATP channel, eNOS, Atg5 signal pathway in HUVECs, and activation of autophagy contributes to Ang II induced dysfunction of HUVECs.
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Angiotensina II/toxicidad , Autofagia , Células Endoteliales de la Vena Umbilical Humana/patología , Acetofenonas/farmacología , Adenina/análogos & derivados , Adenina/farmacología , Animales , Autofagosomas/efectos de los fármacos , Autofagosomas/metabolismo , Autofagia/efectos de los fármacos , Proteínas Relacionadas con la Autofagia/metabolismo , Bencimidazoles/farmacología , Compuestos de Bifenilo/farmacología , Ácidos Decanoicos/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Hidroxiácidos/farmacología , Modelos Biológicos , NG-Nitroarginina Metil Éster/farmacología , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Fosforilación/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Tetrazoles/farmacología , Factores de TiempoRESUMEN
Concentrations of 2-methoxyestradiol (2ME2), a principal metabolite of estradiol, are significantly lower in women with severe preeclampsia. Nitric oxide (NO) released by endothelial nitric oxide synthase (eNOS) plays an important role in regulating cardiovascular homeostasis. Importantly, high-density lipoprotein (HDL) stimulates eNOS activity via endothelial human scavenger receptor class B type I (hSR-BI/CLA-1). Here, we aimed to determine the effect of 2ME2 on hSR-BI/CLA-1 expression in human umbilical vein endothelial cells (HUVECs). hSR-BI/CLA-1 expression was measured by real-time PCR, western blotting and reporter gene assays; eNOS activity was assessed by the measurement of eNOS phosphorylation. Both the mRNA and protein concentrations of hSR-BI/CLA-1 were significantly increased by 2ME2 in HUVECs. 2ME2 also dose-dependently increased the transcriptional activity of the hSR-BI/CLA-1 promoter. The effect of 2ME2 treatment on the promoter activity of hSR-BI/CLA-1 was abrogated by treatment with LY294002, a specific inhibitor of phosphatidylinositol 3-kinase, as was the increase in HDL-induced eNOS activation. Notably, constitutively active Akt increased the activity of the hSR-BI/CLA-1 promoter, whereas dominant-negative Akt abolished the effect of 2ME2 treatment on hSR-BI/CLA-1 promoter activity. The nuclear Sp1 protein concentration was significantly increased by exposure to 2ME2 and Sp1 overexpression increased the promoter activity of the hSR-BI/CLA gene. Furthermore, knockdown of Sp1 inhibited the effect of 2ME2 treatment on hSR-BI/CLA-1 protein expression. These results indicate that 2ME2 treatment increases HDL-dependent eNOS phosphorylation by upregulating endothelial hSR-BI/CLA-1 expression, suggesting that 2ME2 has a potential therapeutic value in the treatment of preeclampsia.
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2-Metoxiestradiol/farmacología , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , 2-Metoxiestradiol/uso terapéutico , Western Blotting , Inmunoprecipitación de Cromatina , Femenino , Humanos , Lipoproteínas HDL/metabolismo , Óxido Nítrico/metabolismo , Preeclampsia/tratamiento farmacológico , Preeclampsia/metabolismo , EmbarazoRESUMEN
BACKGROUND: Myelodysplastic syndromes (MDS) and idiopathic cytopenia of undetermined significance (ICUS) are heterogeneous hematological disorders characterized by hematopoietic dysplasia and/or chromosomal aberrancy. OBJECTIVES: This study aimed to evaluate the diagnostic value of flow cytometry standardized using the European LeukemiaNet (ELN) for MDS and ICUS by analyzing samples obtained from patients with cytopenia based on morphological examination, cytogenetic analysis, and flow cytometry. METHODS: We retrospectively analyzed bone marrow samples aspirated from 253 consecutive patients (median age: 66 years [range: 1-92]) to identify the cause of cytopenia. RESULTS: Sixty patients presented with MDS, and 16 with ICUS. MDS subtypes were distributed as follows: MDS with single-lineage dysplasia (n = 10); MDS with multi-lineage dysplasia (n = 10); MDS with ringed sideroblasts (n = 4); MDS with excess blasts-1 (n = 9); MDS with excess blasts-2 (n = 13), MDS unclassified (n = 5); 5q-syndrome (n = 6); and MDS/myeloproliferative neoplasms (n = 3). Four representative ELN indexes were used. Two or more ELN MDS indexes were in the abnormal range in 35 MDS cases (58.3%) and 4 ICUS cases (25.0%). CONCLUSIONS: Morphological examination remains the standard for MDS diagnosis. Considering the low incidence of genetically proven ICUS (20.2-27.5%), the low sensitivity of ELN MDS indexes for ICUS is considered a valuable alternative.
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Células de la Médula Ósea/metabolismo , Citometría de Flujo/normas , Síndromes Mielodisplásicos/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Células de la Médula Ósea/citología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto JovenRESUMEN
Chronic hyperglycemia causes pancreatic ß-cell dysfunction, impaired insulin secretion and suppression of insulin gene expression, referred to as glucotoxicity. Insulin gene expression is regulated by several protein kinases and protein phosphatases. However, the molecular mechanisms of the suppressed insulin gene expression in glucotoxicity are not fully understood. In this study, we employed rat insulinoma INS-1â¯cells as a model of pancreatic glucotoxicity. In INS-1â¯cells, insulin gene expression is up-regulated by incubation with 11.2â¯mM glucose for 7 days and down-regulated by incubation with 22.4â¯mM glucose for the same period. To identify the protein kinases and protein phosphatases involved in the suppression of insulin gene expression, we analyzed gene expression in INS-1â¯cells cultured with 11.2â¯mM or 22.4â¯mM glucose for 7 days using microarray analysis and real-time PCR. The expression levels of nine protein kinases were affected by glucotoxic conditions. In particular, CPG16 expression level was increased in INS-1â¯cells under these conditions. Transfection of CPG16 decreased insulin promoter activity, whereas kinase-dead mutant of CPG16 did not affect this. These results suggest that CPG16 plays a role in the suppression of insulin gene expression in pancreatic ß-cells under glucotoxic conditions.
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Regulación hacia Abajo , Hiperglucemia/genética , Insulina/genética , Proteínas Serina-Treonina Quinasas/genética , Animales , Línea Celular Tumoral , Quinasas Similares a Doblecortina , Hiperglucemia/complicaciones , Células Secretoras de Insulina/metabolismo , Insulinoma/complicaciones , Insulinoma/genética , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/genética , Ratas , Regulación hacia ArribaRESUMEN
BACKGROUND: We investigated a high-throughput and high-precision forward ABO blood typing screening method that utilizes a general-purpose biochemical analyzer to perform direct red blood cell sampling. METHODS: The blood group antisera used were Ortho® BioClone® Anti-A Serum and Ortho® BioClone® Anti-B Se-rum. AFFIRMAGEN® Reagent Red Blood Cells (Ortho Clinical Diagnostics) were used for AB standard red blood cells. The general-purpose biochemical analyzer employed was the TBATM-120FR HbA1c measurement unit (Canon Medical Systems). RESULTS: ABO blood group of patient samples was determined based on values relative to amount of change in the AFFIRMAGEN® response. Repeatability was CV5% or lower, and testing of 1,112 patient samples showed 100% agreement between the results obtained using the proposed method and those obtained using the tube test method. CONCLUSIONS: The proposed method allows ABO blood typing to be performed simply, quickly, and with a high degree of precision.
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Sistema del Grupo Sanguíneo ABO/sangre , Automatización de Laboratorios , Tipificación y Pruebas Cruzadas Sanguíneas/instrumentación , Tipificación y Pruebas Cruzadas Sanguíneas/métodos , Eritrocitos , Hemoglobina Glucada/análisis , Humanos , Reproducibilidad de los ResultadosRESUMEN
In pancreatic ß cells, ABCA1, a 254 kDa membrane protein, affects cholesterol homeostasis and insulin secretion. Angiotensin II, as the main effector of the renin-angiotensin system, decreases glucose-stimulated insulin secretion (GSIS). We examined the effect of angiotensin II on ABCA1 expression in primary pancreatic islets and INS-1 cells. Angiotensin II decreased ABCA1 protein and mRNA; angiotensin II type 1 receptor (AT1R) blockade rescued this ABCA1 repression. In parallel, angiotensin II suppressed the promoter activity of ABCA1, an effect that was abrogated by PD98095, a specific inhibitor of MAPK kinase (MEK). LXR enhanced ABCA1 promoter activity, and angiotensin II decreased the nuclear abundance of LXR protein. On a chromatin immunoprecipitation assay, LXR mediated the transcription of ABCA1 by directly binding to its promoter. Mutation of the LXR binding site on the ABCA1 promoter cancelled the effect of angiotensin II. Furthermore, angiotensin II induced cholesterol accumulation and impaired GSIS; inhibition of AT1R or MEK pathway reversed these effects. In summary, our study showed that angiotensin II suppressed ABCA1 expression in pancreatic islets and INS-1 cells, indicating that angiotensin II may influence GSIS by regulating ABCA1 expression. Additional research may address therapeutic needs in diseases such as diabetes mellitus.
Asunto(s)
Transportador 1 de Casete de Unión a ATP/metabolismo , Angiotensina II/farmacología , Colesterol/metabolismo , Secreción de Insulina/efectos de los fármacos , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Transportador 1 de Casete de Unión a ATP/genética , Animales , Línea Celular Tumoral , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Células Secretoras de Insulina/citología , Receptores X del Hígado/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratas , Transcripción Genética/efectos de los fármacosRESUMEN
Selenoprotein P (encoded by SELENOP in humans, Selenop in rat), a liver-derived secretory protein, induces resistance to insulin and vascular endothelial growth factor (VEGF) in type 2 diabetes. Suppression of selenoprotein P may provide a novel therapeutic approach to treating type 2 diabetes; however, few drugs inhibiting SELENOP expression in hepatocytes have been identified. The present findings demonstrate that eicosapentaenoic acid (EPA) suppresses SELENOP expression by inactivating sterol regulatory element-binding protein-1c (SREBP-1c, encoded by Srebf1 in rat) in H4IIEC3 hepatocytes. Treatment with EPA caused concentration- and time-dependent reduction in SELENOP promoter activity. EPA activated AMP-activated protein kinase (AMPK); however, the inhibitory effect of EPA on SELENOP promoter activity was not canceled with an AMPK inhibitor compound C and dominant-negative AMPK transfection. Deletion mutant promoter assays and computational analysis of transcription factor-binding sites conserved among the species resulted in identification of a sterol regulatory element (SRE)-like site in the SELENOP promoter. A chromatin immunoprecipitation (ChIP) assay revealed that EPA decreases binding of SREBP-1c to the SELENOP promoter. Knockdown of Srebf1 resulted in a significant down-regulation of Selenop expression. Conversely, SREBP-1c overexpression inhibited the suppressive effect of EPA. These data provide a novel mechanism of action for EPA involving improvement of systemic insulin sensitivity through the regulation of selenoprotein P production independently of the AMPK pathway and suggest an additional approach to developing anti-diabetic drugs.
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Regulación hacia Abajo/efectos de los fármacos , Ácido Eicosapentaenoico/farmacología , Hepatocitos/metabolismo , Selenoproteína P/biosíntesis , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Animales , Línea Celular Tumoral , Humanos , Ratas , Selenoproteína P/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genéticaRESUMEN
Recently, several clinical studies have suggested that adult growth hormone (GH) deficiency that also has low concentration of IGF1 is associated with an increased prevalence of fatty liver (FL). ATP-binding cassette transporter A1 (ABCA1) is a pivotal regulator of lipid efflux from cells to apolipoproteins and plays an important role on formation of FL. In this study, we determined the effects of IGF1 on ABCA1 expression in GH-deficient mice to clarify its effects on FL. Western blotting, real-time PCR, and a luciferase assay were employed to examine the effect of IGF1. The binding of FoxO1 to the ABCA1 promoter was assessed by chromatin immunoprecipitation (ChIP) assay. Cholesterol accumulation was analyzed by Oil Red O stain and cholesterol content measurement. We confirmed that IGF1 upregulated the ABCA1 expression. The activity of a reporter construct containing the ABCA1 promoter was induced by IGF1, and this effect was blocked by LY294002, a specific inhibitor of phosphatidylinositol 3-kinase (PI3K). Constitutively active Akt stimulated the ABCA1 promoter activity, and a dominant-negative mutant of Akt or mutagenesis of the FoxO1 response element abolished the effect of IGF1. A ChIP assay indicated that FoxO1 mediated IGF1 transcriptional activity by directly binding to the ABCA1 promoter region. For in vivo experiments, we used an inhibitor for the GH receptor (Pegvisomant) to reduce the IGF1 level. A high-fat diet induced FL in mice (C57BL/6J) given Pegvisomant treatment. IGF1 treatment stimulated ABCA1 expression to improve cholesterol accumulation in these mice. These results show that the PI3K/Akt/FoxO1 pathway contributes to the regulation of ABCA1 expression in response to IGF1 stimulation that suppressed FL in GH-deficient mice.
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Transportador 1 de Casete de Unión a ATP/metabolismo , Colesterol/metabolismo , Enanismo Hipofisario/metabolismo , Hígado Graso/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Hígado/metabolismo , Animales , Dieta Alta en Grasa , Proteína Forkhead Box O1/metabolismo , Células Hep G2 , Hormona de Crecimiento Humana/análogos & derivados , Hormona de Crecimiento Humana/farmacología , Humanos , Hígado/efectos de los fármacos , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
Selenoprotein P (SeP; encoded by SEPP1 in humans) is a liver-derived secretory protein that induces insulin resistance in type 2 diabetes. Suppression of SeP might provide a novel therapeutic approach to treating type 2 diabetes, but few drugs that inhibit SEPP1 expression in hepatocytes have been identified to date. The present findings demonstrate that metformin suppresses SEPP1 expression by activating AMP-activated kinase (AMPK) and subsequently inactivating FoxO3a in H4IIEC3 hepatocytes. Treatment with metformin reduced SEPP1 promoter activity in a concentration- and time-dependent manner; this effect was cancelled by co-administration of an AMPK inhibitor. Metformin also suppressed Sepp1 gene expression in the liver of mice. Computational analysis of transcription factor binding sites conserved among the species resulted in identification of the FoxO-binding site in the metformin-response element of the SEPP1 promoter. A luciferase reporter assay showed that metformin suppresses Forkhead-response element activity, and a ChIP assay revealed that metformin decreases binding of FoxO3a, a direct target of AMPK, to the SEPP1 promoter. Transfection with siRNAs for Foxo3a, but not for Foxo1, cancelled metformin-induced luciferase activity suppression of the metformin-response element of the SEPP1 promoter. The overexpression of FoxO3a stimulated SEPP1 promoter activity and rescued the suppressive effect of metformin. Metformin did not affect FoxO3a expression, but it increased its phosphorylation and decreased its nuclear localization. These data provide a novel mechanism of action for metformin involving improvement of systemic insulin sensitivity through the regulation of SeP production and suggest an additional approach to the development of anti-diabetic drugs.
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Proteínas Quinasas Activadas por AMP/metabolismo , Factores de Transcripción Forkhead/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Hipoglucemiantes/farmacología , Metformina/farmacología , Selenoproteína P/biosíntesis , Proteínas Quinasas Activadas por AMP/genética , Transporte Activo de Núcleo Celular/efectos de los fármacos , Transporte Activo de Núcleo Celular/genética , Animales , Línea Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/metabolismo , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/genética , Regulación de la Expresión Génica/genética , Humanos , Ratones , Fosforilación/efectos de los fármacos , Fosforilación/genética , Ratas , Elementos de Respuesta/efectos de los fármacos , Elementos de Respuesta/genética , Selenoproteína P/genéticaRESUMEN
MicroRNAs (miRNAs) are short, noncoding RNAs that modulate genes posttranscriptionally. Frequent gains and losses of miRNA genes have been reported to occur during evolution. However, little is known systematically about the periods of evolutionary origin of the present miRNA gene repertoire of an extant mammalian species. Thus, in this study, we estimated the evolutionary periods during which each of 1,433 present human miRNA genes originated within 15 periods, from human to platypus-human common ancestral branch and a class "conserved beyond theria," primarily using multiple genome alignments of 38 species, plus the pairwise genome alignments of five species. The results showed two peak periods in which the human miRNA genes originated at significantly accelerated rates. The most accelerated rate appeared in the period of the initial phase of hominoid lineage, and the second appeared shortly before Laurasiatherian divergence. Approximately 53% of the present human miRNA genes have originated within the simian lineage to human. In particular, approximately 28% originated within the hominoid lineage. The early phase of placental mammal radiation comprises approximately 28%, while no more than 15% of human miRNAs have been conserved beyond placental mammals. We also clearly showed a general trend, in which the miRNA expression level decreases as the miRNA becomes younger. Intriguingly, amid this decreasing trend of expression, we found one significant rise in the expression level that corresponded to the initial phase of the hominoid lineage, suggesting that increased functional acquisitions of miRNAs originated at this particular period.
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Evolución Molecular , Hominidae/genética , MicroARNs/genética , Modelos Genéticos , Animales , Cromosomas Humanos , Simulación por Computador , Expresión Génica , Especiación Genética , Genoma , Humanos , Mamíferos/genética , MicroARNs/metabolismo , Anotación de Secuencia Molecular , Familia de MultigenesRESUMEN
Autophagy has emerged as a powerful process in the response to cellular injury. The present study was designed to investigate signal transduction pathways in angiotensin II (Ang II)-induced autophagy. Rat vascular smooth muscle cells (VSMCs) were stimulated with different doses of Ang II (10(-9)-10(-5) mol/L) for different time periods (6-72 h). Incubation with Ang II increased the production of reactive oxygen species (ROS), increased the LC3-II to LC3-I ratio, increased beclin-1 expression, and decreased SQSTM1/p62 expression in a dose- and time-dependent manner. In addition, Ang II increased autophagosome formation. Increased ROS production induced by Ang II was inhibited by Ang II type 1 receptor (AT1) blockers (Olmesartan and Candesartan, ARB), a NADPH Oxidase inhibitor (apocynin), and mitochondrial KATP channels inhibitor (5-hydroxydecanoate, 5HD). Ang II (10(-7) mol/L, 48 h)-induced increase in the LC3-II to LC3-I ratio, the formation of autophagosomes, expression of beclin-1 and decrease in the expression of SQSTM1/p62 were also inhibited by pretreatment with 3-methyladenine or bafilomycin A1 (inhibitors of autophagy), olmesartan and candesartan (in dose-dependent manners), apocynin, 5HD, and siRNA Atg5. Our results indicate that Ang II increases autophagy levels via activation of AT1 receptor and NADPH oxidase. Mitochondrial KATP channels also play an important role in Ang II-induced autophagy. Our results may provide a new strategy for treatment of cardiovascular diseases with Ang II.
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Angiotensina II/farmacología , Autofagia/efectos de los fármacos , Mitocondrias Musculares/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Miocitos del Músculo Liso/efectos de los fármacos , Canales de Potasio/efectos de los fármacos , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteína 5 Relacionada con la Autofagia , Beclina-1 , Células Cultivadas , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Proteínas de Choque Térmico/metabolismo , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Mitocondrias Musculares/metabolismo , Mitocondrias Musculares/patología , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/metabolismo , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio/metabolismo , Proteínas/genética , Proteínas/metabolismo , Interferencia de ARN , Ratas , Especies Reactivas de Oxígeno/metabolismo , Receptor de Angiotensina Tipo 1/agonistas , Receptor de Angiotensina Tipo 1/metabolismo , Proteína Sequestosoma-1 , Transducción de Señal/efectos de los fármacos , Factores de Tiempo , TransfecciónRESUMEN
Cardio-ankle vascular index (CAVI) has been demonstrated as a parameter of arterial stiffness, which antihypertensive therapy may improve. However, little information is available about the factors affecting changes in arterial stiffness assessed by CAVI during antihypertensive therapy. We performed a study to examine the factors affecting changes in arterial stiffness assessed by CAVI during antihypertensive therapy. Eighty treated hypertensive patients (71 ± 10 years) were divided into two groups: 50 patients showing a decrease in CAVI (Group 1) and 30 patients showing an increase (Group 2) during observation (24 ± 11 months) of antihypertensive therapy. The groups did not differ in the rates of use of angiotensin II receptor blockers or calcium channel blockers. Age (Group 1: 67 ± 11 versus Group 2: 74 ± 8 years), left ventricular mass index (LVMI) (Group 1: 103 ± 19 versus Group 2: 120 ± 24 g/m(2)) and systolic blood pressure (Group 1: 133 ± 17 versus Group 2: 144 ± 23 mm Hg) at the start of observation were significantly higher in Group 2 than in Group 1 (p = 0.003, p = 0.001 and p = 0.027, respectively). The changes in CAVI during observation were correlated only with LVMI (r = 0.289, p = 0.009) at the start of observation for all 80 patients. It may be difficult to improve arterial stiffness assessed by CAVI during antihypertensive therapy in hypertensive patients with left ventricular hypertrophy.
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Presión Sanguínea/fisiología , Hipertensión/complicaciones , Hipertrofia Ventricular Izquierda/fisiopatología , Rigidez Vascular/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Índice Tobillo Braquial , Progresión de la Enfermedad , Ecocardiografía , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/diagnóstico por imagen , Hipertensión/fisiopatología , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/etiología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios RetrospectivosRESUMEN
The nationwide surveillance of antibacterial susceptibility to meropenem (MEPM) and other parenteral antibiotics against clinical isolates during 2012 in Japan was conducted. A total of 2985 strains including 955 strains of Gram-positive bacteria, 1782 strains of Gram-negative bacteria, and 248 strains of anaerobic bacteria obtained from 31 medical institutions were examined. The results were as follows; 1. MEPM was more active than the other carbapenem antibiotics tested against Gram-negative bacteria, especially against enterobacteriaceae and Haemophilus influenzae. MEPM was also active against most of the species tested in Gram-positive and anaerobic bacteria, except for multi-drug resistant strains including methicillin-resistant Staphylococcus aureus (MRSA). 2. Of all species tested, there were no species, which MIC90 of MEPM was more than 4-fold higher than those in our previous studies in 2009 or 2006. Therefore, the tendency to increase in antimicrobial resistance rates was not observed. 3. MEPM resistance against Pseudomonas aeruginosa was 17.8% (56/315 strains). Compared to our previous results, it was the lowest than that in 2006 and 2009. 4. Carbapenem-resistant Klebsiella pneumoniae, and multi-drug-resistant Acinetobacter species, which emerged in worldwide, were not observed. 5. The proportion of extended-spectrum beta-lactamase (ESBL) strains was 6.2% (59/951 strains) in enterobacteriaceae, which increased compared with that of our previous studies in 2009 or before. Whereas, the proportion of metallo-beta-lactamase strains was 1.6% (5/315 strains) in P. aeruginosa, which was stable. In conclusion, the results from this surveillance suggest that MEPM retains its potent and broad antibacterial activity and therefore is a clinically useful carbapenem for serious infections treatment at present, 17 years passed after available for commercial use in Japan.
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Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Tienamicinas/farmacología , Farmacorresistencia Bacteriana , Humanos , Meropenem , Pruebas de Sensibilidad MicrobianaRESUMEN
Although increased oxidative stress is known to be associated with worsened cardiac function in chronic heart failure, consensus is still lacking regarding the association between oxidative stress and cardiac function in hypertensive patients without overt heart disease. This study aimed to evaluate the association between oxidative stress assessed by urinary 8-hydroxydeoxyguanosine (8-OHdG) and cardiac function in hypertensive patients without overt heart disease. We enrolled a total of 80 hypertensive patients (70 ± 11 y) who had been taking antihypertensive medications for at least 1 year. Urinary 8-OHdG levels were measured by an immunochromatographic assay (ICR-001, Selista Inc., Tokyo, Japan). Echocardiography was performed to assess the left ventricular (LV) diastolic function by measuring early diastolic mitral annular velocity (e') and the ratio of early transmitral flow velocity (E) to e' (E/e'). Urinary 8-OHdG was correlated with E/e' (r = 0.346, P = .002), e' (r = -0.310, P = .005), and HbA1c (r = 0.276, P = .013). Multiple linear regression analysis revealed that only e' (ß = -0.343, P = .004) was an independent determinant of urinary 8-OHdG. In conclusion, decreased e' is independently associated with elevated urinary 8-OHdG, a marker of oxidative stress, in hypertensive patients. Therefore, an elevated urinary 8-OHdG level may be useful in detecting subclinical LV diastolic dysfunction in hypertensive patients without overt heart disease.
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Desoxiguanosina/análogos & derivados , Corazón/fisiología , Hipertensión/fisiopatología , Estrés Oxidativo/fisiología , 8-Hidroxi-2'-Desoxicoguanosina , Adulto , Anciano , Anciano de 80 o más Años , Antihipertensivos/uso terapéutico , Biomarcadores/orina , Estudios Transversales , Desoxiguanosina/orina , Ecocardiografía , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/orina , Masculino , Persona de Mediana Edad , Función Ventricular Izquierda/fisiologíaRESUMEN
High sugar consumption increases the risk of diabetes, obesity, and cardiovascular diseases. Regarding the diet of patients with diabetes, artificial sweeteners are considered a safe alternative to sugar; however, there is also a risk that artificial sweeteners exacerbate glucose metabolism. D-allulose (C-3 isomer of d-fructose), which is a rare sugar, has been reported to have antidiabetic and antiobesity effects. In this study, the efficacy of a diabetic diet containing D-allulose was investigated in patients with type 2 diabetes using an intermittently scanned continuous glucose monitoring system (isCGM). This study was a validated, prospective, single-blind, randomized, crossover comparative study. Comparison of peak postprandial blood glucose (PPG) levels after consumption of a standard diabetic diet and a diabetic diet containing 8.5 g of D-allulose was the primary endpoint. A D-allulose-containing diabetic diet improved PPG levels in type two diabetes patients compared with a strictly energy-controlled diabetic diet. The results also showed a protective effect on endogenous pancreatic insulin secretory capacity owing to reduced insulin requirement. In patients with type two diabetes mellitus, diabetic diets containing 8.5 g D-allulose were effective in improving PPG levels.
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Diabetes Mellitus Tipo 2 , Humanos , Dieta para Diabéticos , Estudios Cruzados , Proyectos Piloto , Azúcares , Glucemia/metabolismo , Método Simple Ciego , Automonitorización de la Glucosa Sanguínea , Estudios Prospectivos , Fructosa/efectos adversos , Edulcorantes , InsulinaRESUMEN
BACKGROUND: Exposing blood serum samples to ambient white light-emitting diode (WLED) light may accelerate bilirubin photoisomer production. We previously demonstrated the quantitative effect of bilirubin configurational isomers (BCI) on direct bilirubin (DB) value using the vanadate oxidation method. However, the effects of bilirubin structural photoisomers (BSI) remain unclear. METHODS: In Study 1, the relationship between WLED irradiation time and BSI production was examined. Serum samples from five neonates were irradiated with WLED light for 0, 10, 30, 60 and 180 min. Bilirubin isomer concentration and BSI production rates were calculated. In Study 2, we performed quantitative investigation of BSI effect on DB values: Differences in DB, BCI and BSI values before and after irradiation were calculated as â¿DB, â¿BCI and â¿BSI, respectively. Assuming the coefficient of BCI affecting DB values was 'a', relational expression was â¿DB = a*â¿BSI + 0.19*â¿BCI. Serum samples from 15 neonates were irradiated with green LED light for 10 and 30 s. The respective bilirubin isomer levels were measured, and the coefficient was derived. RESULTS: In Study 1, the median BSI production rate was 0.022 mg/dL per min in specimens with an unconjugated bilirubin concentration of 10.88 mg/dL. In Study 2, assuming that â¿DB-0.19*â¿BCI was Y and â¿BSI was X, the relational expression was Y = 0.34X-0.03 (R2 = 0.87; p < .01) and a = 0.34. CONCLUSIONS: Under ambient WLED light, serum sample generated 1.3 mg/dL BSIs in 1 h. Approximately 34% (0.44 mg/dL) of BSI concentrations was measured as DB when using the vanadate oxidation method according to the above equation.
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Fototerapia , Vanadatos , Recién Nacido , Humanos , Fototerapia/métodos , Luz , Bilirrubina , IsomerismoRESUMEN
Transcription factors (TFs) and microRNAs (miRNAs) comprise two major layers of gene regulatory networks (GRNs). TFs and miRNAs function coordinately, but they have distinct molecular mechanisms and evolutionary backgrounds. Therefore, we aimed to systematically reveal the difference in contribution between TF and miRNA networks to the evolution of their coordinated regulations by focusing on composite feedforward circuits (cFFCs) that each comprises a TF and an miRNA. We compiled 124,736 human-mouse conserved TF regulatory connections and 34,298 conserved miRNA regulatory connections into two distinct connection matrices. To differentially assess the contributions to cFFC formation of TFs and miRNAs, we randomized one matrix and kept the other unchanged and subsequently examined the number of cFFCs, the number of cFFC-targeted genes, and the redundancy formed by cFFCs in comparison with those of the real GRNs. Because the matrices represent selectively constrained networks, if selection has been operating on the networks for or against cFFC formation, the values of cFFC network properties would deviate significantly from the expectation of the randomized networks. As the cFFC includes both TF and miRNA connections, the partial randomizations indicate the extent of influence of selection on cFFC formation differentially between TF and miRNA networks. Thus, we adopted the deviation of each cFFC network property value as a measure to estimate the extent of influence of selection on cFFCs and to compare the contribution between TF and miRNA networks. We found that miRNA regulatory networks changed their configuration such that they conformed to the stable TF regulatory networks with an increased circuit redundancy and a marked reduction in the repertoire of cFFC-targeted genes. We also revealed that this redundancy-adding role is preferentially attributable to miRNA network alterations. The results indicate that the redundancy-adding role might serve as a niche for many miRNA connections to survive, avoiding conflicts with the stable TF regulatory networks.