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1.
Anticancer Res ; 44(2): 489-495, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38307564

RESUMEN

BACKGROUND/AIM: Individuals with Down syndrome (DS), attributed to triplication of human chromosome 21 (Hsa21), exhibit a reduced incidence of solid tumors. However, the prevalence of glioblastoma among individuals with DS remains a contentious issue in epidemiological studies. Therefore, this study examined the gliomagenicity in Ts1Cje mice, a murine model of DS. MATERIALS AND METHODS: We employed the Sleeping Beauty transposon system for the integration of human oncogenes into cells of the subventricular zone of neonatal mice. RESULTS: Notably, Sleeping Beauty-mediated de novo murine gliomagenesis was significantly suppressed in Ts1Cje mice compared to wild-type mice. In glioblastomas of Ts1je mice, we observed an augmented presence of M1-polarized tumor-associated macrophages and microglia, known for their anti-tumor efficacy in the early stage of tumor development. CONCLUSION: Our findings in a mouse model of DS offer novel perspectives on the diminished gliomagenicity observed in individuals with DS.


Asunto(s)
Síndrome de Down , Ratones , Animales , Humanos , Síndrome de Down/genética , Síndrome de Down/patología , Modelos Animales de Enfermedad
2.
Biol Pharm Bull ; 46(9): 1169-1175, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37661395

RESUMEN

Down syndrome (DS), which is caused by triplication of human chromosome 21 (Hsa21), exhibits some physical signs of accelerated aging, such as graying hair, wrinkles and menopause at an unusually young age. Development of early-onset Alzheimer's disease, which is frequently observed in adults with DS, is also suggested to occur due to accelerated aging of the brain. Several Hsa21 genes are suggested to be responsible for the accelerated aging in DS. In this review, we summarize these candidate genes and possible molecular mechanisms, and discuss the related key factors. In particular, we focus on copper, an essential trace element, as a key factor in the accelerated aging in DS. In addition, the physiological significance of brain copper accumulation in cognitive impairment is discussed. We herein provide our hypothesis on the copper dyshomeostasis-based pathophysiology of DS.


Asunto(s)
Disfunción Cognitiva , Síndrome de Down , Adulto , Humanos , Femenino , Síndrome de Down/genética , Cobre , Envejecimiento , Disfunción Cognitiva/genética , Aceleración
3.
Biol Pharm Bull ; 46(3): 488-493, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36858578

RESUMEN

Hepatic fibrosis, a primary feature of non-alcoholic steatohepatitis (NASH), develops with inflammation and subsequent activation of hepatic stellate cells (HSCs), the main extracellular matrix-producing cells. Currently, no approved pharmacotherapy is available to treat hepatic fibrosis, even under dietary intervention. The activation of cultured HSCs has been shown to be attenuated by pharmacological inhibition of group IVA phospholipase A2 (IVA-PLA2), an enzyme initiating the generation of lipid proinflammatory mediators. We examined the potential utility of IVA-PLA2 of HSCs as a therapeutic target for hepatic fibrosis in NASH under dietary modification using collagen-producing cell-specific IVA-PLA2-conditional knockout mice fed a high-fat diet and then returned to a normal one. Apparent hepatic fibrosis and the accumulation of hepatic lipid droplets developed in the IVA-PLA2-conditional knockout mice on a high-fat diet for nine weeks to a similar degree as in control mice. Most of the lipid droplets disappeared five weeks after switching the diet back to a normal one in both genetic mice. In contrast, the hepatic fibrosis in control mice still progressed even after changing back to a normal diet. However, deficiency of IVA-PLA2 in collagen-producing cells alleviated the aggravated hepatic fibrosis under dietary modification. Our results revealed that the protective effects of an HSC-specific IVA-PLA2 deficiency on fibrogenesis appear after switching the diet from a high-fat one back to a normal one, supporting the promising beneficial effects of the inhibition of IVA-PLA2 on progressive hepatic fibrosis under dietary intervention in NASH treatment.


Asunto(s)
Dieta Alta en Grasa , Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Cirrosis Hepática , Colágeno , Ratones Noqueados , Fosfolipasas A2
4.
Biol Pharm Bull ; 46(2): 320-333, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36724960

RESUMEN

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by dementia. The most characteristic pathological changes in AD brain include extracellular amyloid-ß (Aß) accumulation and neuronal loss. Particularly, cholinergic neurons in the nucleus basalis of Meynert are some of the first neuronal groups to degenerate; accumulating evidence suggests that Aß oligomers are the primary form of neurotoxicity. Bacopa monniera is a traditional Indian memory enhancer whose extract has shown neuroprotective and Aß-reducing effects. In this study, we explored the low molecular weight compounds from B. monniera extracts with an affinity to Aß aggregates, including its oligomers, using Aß oligomer-conjugated beads and identified plantainoside B. Plantainoside B exhibited evident neuroprotective effects by preventing Aß attachment on the cell surface of human induced pluripotent stem cell (hiPSC)-derived cholinergic neurons. Moreover, it attenuated memory impairment in mice that received intrahippocampal Aß injections. Furthermore, radioisotope experiments revealed that plantainoside B has affinity to Aß aggregates including its oligomers and brain tissue from a mouse model of Aß pathology. In addition, plantainoside B could delay the Aß aggregation rate. Accordingly, plantainoside B may exert neuroprotective effects by binding to Aß oligomers, thus interrupting the binding of Aß oligomers to the cell surface. This suggests its potential application as a theranostics in AD, simultaneously diagnostic and therapeutic drugs.


Asunto(s)
Enfermedad de Alzheimer , Bacopa , Células Madre Pluripotentes Inducidas , Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Ratones , Humanos , Animales , Bacopa/metabolismo , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Células Madre Pluripotentes Inducidas/metabolismo , Péptidos beta-Amiloides/toxicidad , Péptidos beta-Amiloides/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/tratamiento farmacológico
5.
Dev Neurobiol ; 82(6): 457-475, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35724379

RESUMEN

Neural communication in the adult nervous system is mediated primarily through chemical synapses, where action potentials elicit Ca2+ signals, which trigger vesicular fusion and neurotransmitter release in the presynaptic compartment. At early stages of development, the brain is shaped by communication via trophic factors and other extracellular signaling, and by contact-mediated cell-cell interactions including chemical synapses. The patterns of early neuronal impulses and spontaneous and regulated neurotransmitter release guide the precise topography of axonal projections and contribute to determining cell survival. The study of the role of specific proteins of the synaptic vesicle release machinery in the establishment, plasticity, and maintenance of neuronal connections during development has only recently become possible, with the advent of mouse models where various members of the N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex have been genetically manipulated. We provide an overview of these models, focusing on the role of regulated vesicular release and/or cellular excitability in synaptic assembly, development and maintenance of cortical circuits, cell survival, circuit level excitation-inhibition balance, myelination, refinement, and plasticity of key axonal projections from the cerebral cortex. These models are important for understanding various developmental and psychiatric conditions, and neurodegenerative diseases.


Asunto(s)
Proteínas SNARE , Vesículas Sinápticas , Animales , Ratones , Proteínas Sensibles a N-Etilmaleimida/metabolismo , Neurotransmisores/metabolismo , Proteínas SNARE/metabolismo , Sinapsis/metabolismo , Vesículas Sinápticas/metabolismo
6.
Life Sci ; 294: 120355, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35093339

RESUMEN

AIM: Non-alcoholic steatohepatitis (NASH) is characterized by steatosis, inflammatory responses and fibrosis. Our previous studies provided evidence that group IVA phospholipase A2 (IVA-PLA2), a key PLA2 isozyme in the arachidonic acid cascade, is involved in the development of NASH. However, which types of cells are critical for the IVA-PLA2-dependent onset and progression of NASH is unclear. We elucidated the effects of the cell-type-specific deficiency of IVA-PLA2 in mice on the development of NASH. MAIN METHODS: Cell-type-specific IVA-PLA2-conditional knockout (cKO) mice and littermate controls were fed a choline-deficient, L-amino-acid-defined, high-fat diet with 0.1% methionine as a NASH model. The degree of hepatic fibrosis was evaluated by staining with picric acid-Sirius red, and the number of activated hepatic stellate cells was determined by immunoblotting and immunostaining for α-smooth muscle actin. Sinusoidal capillarization was analyzed by scanning electron microscopy. KEY FINDINGS: The deposition of collagen and number of activated hepatic stellate cells were markedly reduced in endothelial cell/liver sinusoidal endothelial cell (EC/LSEC)-specific IVA-PLA2 cKO mice but not in hepatocyte-, monocyte/macrophage-, or hepatic stellate cell-specific IVA-PLA2 cKO mice. In addition, EC/LSEC-specific IVA-PLA2-deficient mice showed more fenestrae than control mice fed a CDAHFD, indicating suppression of sinusoidal capillarization. SIGNIFICANCE: These results suggest that ECs/LSECs contribute to the IVA-PLA2-dependent onset and/or progression of NASH. Endothelial IVA-PLA2 is a promising factor for promoting sinusoidal capillarization and the ensuing HSC activation and fibrosis; thus IVA-PLA2 in ECs/LSECs is a potential therapeutic target for NASH.


Asunto(s)
Capilares/patología , Células Endoteliales/patología , Fosfolipasas A2 Grupo IV/fisiología , Cirrosis Hepática/patología , Neovascularización Patológica/patología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Animales , Capilares/enzimología , Células Endoteliales/enzimología , Cirrosis Hepática/enzimología , Cirrosis Hepática/etiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neovascularización Patológica/enzimología
7.
Biochem Biophys Res Commun ; 535: 87-92, 2021 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-33348080

RESUMEN

Down syndrome (DS, Trisomy 21) is the most common genetic cause of delayed fetal brain development and postnatal intellectual disability. Although delayed fetal brain development might be involved in intellectual disability, no evidence of an association between these abnormal phenotypes has been shown. To identify molecules differentially expressed in both the prenatal forebrain and adult hippocampus of Ts1Cje mice, a mouse model of DS, we employed a transcriptomic analysis. In the present study, we conducted transcriptomic profiling of the hippocampus of adult Ts1Cje mice and compared the results with the previously obtained transcriptomic profile of the prenatal forebrain at embryonic day 14.5. Results showed that the Tbx1 mRNA expression was decreased at both life stages. In addition, the decreased expression of Tbx1 mRNA was confirmed in other DS mouse models, Dp(16)1Yey/+ and Ts1Rhr mice, which carry longer and shorter trisomic regions, respectively. Taken together, these findings suggest that Tbx1 may link the delayed fetal brain development and intellectual disability in DS.


Asunto(s)
Encéfalo/embriología , Síndrome de Down/genética , Embrión de Mamíferos/metabolismo , Regulación del Desarrollo de la Expresión Génica , Proteínas de Dominio T Box/genética , Animales , Modelos Animales de Enfermedad , Regulación hacia Abajo/genética , Hipocampo/metabolismo , Ratones Endogámicos C57BL , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcriptoma
8.
Mol Brain ; 13(1): 140, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33059734

RESUMEN

α2-Antiplasmin (α2AP), a principal physiological plasmin inhibitor, is mainly produced by the liver and kidneys, but it is also expressed in several parts of the brain, including the hippocampus and cerebral cortex. Our previous study demonstrated that α2AP knockout mice exhibit spatial memory impairment in comparison to wild-type mice, suggesting that α2AP is necessary for the fetal and/or neonatal development of the neural network for spatial memory. However, it is still unclear whether α2AP plays a role in the memory process. The present study demonstrated that adult hippocampal neurogenesis and remote spatial memory were enhanced by the injection of an anti-α2AP neutralizing antibody in WT mice, while the injection of α2AP reduced hippocampal neurogenesis and impaired remote spatial memory, suggesting that α2AP is a negative regulator in memory processing. The present study also found that the levels of α2AP in the brains of old mice were higher than those in young mice, and a negative correlation between the α2AP level and spatial working memory. In addition, aging-dependent brain oxidative stress and hippocampal inflammation were attenuated by α2AP deficiency. Thus, an age-related increase in α2AP might cause cognitive decline accompanied by brain oxidative stress and neuroinflammation. Taken together, our findings suggest that α2AP is a key regulator of the spatial memory process, and that it may represent a promising target to effectively regulate healthy brain aging.


Asunto(s)
Envejecimiento/patología , Disfunción Cognitiva/metabolismo , Disfunción Cognitiva/fisiopatología , Memoria Espacial/fisiología , alfa 2-Antiplasmina/metabolismo , Animales , Anticuerpos Neutralizantes/metabolismo , Hipocampo/fisiopatología , Inflamación/patología , Masculino , Ratones Endogámicos C57BL , Neurogénesis , Estrés Oxidativo , alfa 2-Antiplasmina/deficiencia
9.
Brain Pathol ; 30(1): 75-91, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31206867

RESUMEN

Some mouse models of Down syndrome (DS), including Ts1Cje mice, exhibit impaired prenatal neurogenesis with yet unknown molecular mechanism. To gain insights into the impaired neurogenesis, a transcriptomic and flow cytometry analysis of E14.5 Ts1Cje embryo brain was performed. Our analysis revealed that the neutrophil and monocyte ratios in the CD45-positive hematopoietic cells were relatively increased, in agreement with the altered expression of inflammation/immune-related genes, in Ts1Cje embryonic brain, whereas the relative number of brain macrophages was decreased in comparison to wild-type mice. Similar upregulation of inflammation-associated mRNAs was observed in other DS mouse models, with variable trisomic region lengths. We used genetic manipulation to assess the contribution of Erg, a trisomic gene in these DS models, known to regulation hemato-immune cells. The perturbed proportions of immune cells in Ts1Cje mouse brain were restored in Ts1Cje-Erg+/+/Mld2 mice, which are disomic for functional Erg but otherwise trisomic on a Ts1Cje background. Moreover, the embryonic neurogenesis defects observed in Ts1Cje cortex were reduced in Ts1Cje-Erg+/+/Mld2 embryos. Our findings suggest that Erg gene triplication contributes to the dysregulation of the homeostatic proportion of the populations of immune cells in the embryonic brain and decreased prenatal cortical neurogenesis in the prenatal brain with DS.


Asunto(s)
Síndrome de Down/genética , Neurogénesis/genética , Regulador Transcripcional ERG/genética , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Síndrome de Down/inmunología , Femenino , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neurogénesis/inmunología , Proteínas Oncogénicas/genética , Proteínas Oncogénicas/metabolismo , Embarazo , Regulador Transcripcional ERG/metabolismo , Transcriptoma
10.
Nihon Yakurigaku Zasshi ; 154(6): 335-339, 2019.
Artículo en Japonés | MEDLINE | ID: mdl-31787686

RESUMEN

Down syndrome caused by triplication of human chromosome 21 (HSA21) is the most frequent aneuploidy, resulting in mental retardation, intellectual disability and accelerated aging. Individuals with DS are at an increased risk of developing Alzheimer's disease (AD)-like dementia, with up to 75% of DS people in their 60s developing dementia. Oxidative stress is widely accepted as a mechanism underlying a number of DS symptoms, such as accelerated aging and cognitive decline. Superoxide disumutase 1 (Sod1) and amiloyd precursor protein (App) genes are suggested as the candidate genes in HSA21 underlying the enhanced oxidative stress in individuals with DS. However, we previously demonstrated that the Ts1Cje mouse model, which has a normal copy number of both candidate genes, also shows enhanced oxidative stress, suggesting that triplicated genes other than Sod1 and App likely enhance oxidative stress in the brain of DS people. To identify the molecules with enhanced oxidative stress in Ts1Cje mice, we performed several -omics analyses. Recently, we showed that copper was accumulated in the brain of adult Ts1Cje mice in an analysis using inductively coupled plasma mass spectrometry (ICP-MS), and a low-copper diet was able to improve the elevated levels of copper. The low-copper diet also resolved some anomalies, such as the enhanced oxidative stress, accumulation of phosphorylated tau and low anxiety. These findings suggest that the accumulation of copper in the DS brain may be a therapeutic target for ameliorating a number of abnormal phenotypes in individuals with DS.


Asunto(s)
Encéfalo/fisiopatología , Cobre/metabolismo , Síndrome de Down/fisiopatología , Adulto , Enfermedad de Alzheimer , Animales , Modelos Animales de Enfermedad , Humanos , Ratones
11.
Yakugaku Zasshi ; 139(9): 1155-1162, 2019.
Artículo en Japonés | MEDLINE | ID: mdl-31474631

RESUMEN

Nonalcoholic steatohepatitis (NASH) is a lifestyle-related disease characterized by hepatic fibrosis with the accumulation of fat and inflammation and can progress to cirrhosis or hepatocellular carcinoma. However, effective pharmacotherapeutic strategies for hepatic fibrosis in NASH remain to be established. Among the initiators of inflammation, we have been investigating the possible involvement of group IVA phospholipase A2 (IVA-PLA2), which catalyzes the initial step in the generation of lipid mediators, including eicosanoids and lysophospholipids, in the progression of hepatic fibrosis. We have recently demonstrated that a lack of IVA-PLA2 alleviates hepatic fibrosis in NASH model mice fed a high-fat and high-cholesterol diet and in CCl4-treated mice. CCl4-induced hepatic fibrosis was also prevented by the administration of an orally active, specific IVA-PLA2 inhibitor even after hepatic fibrosis had developed. Based on these findings suggesting that IVA-PLA2 mediates the cellular responses contributing to the progression of hepatic fibrosis, we have been exploring which types of cells in the liver are involved in IVA-PLA2-mediated hepatic fibrosis using cell-specific IVA-PLA2 knockout mice. The preliminary experimental results suggest that IVA-PLA2 in endothelial cells, but not monocyte-derived cells, plays a role, in part, in the hepatic stellate cell-mediated progression of hepatic fibrosis. In this paper, we discuss the possibility that IVA-PLA2 and/or its related molecules are candidate pharmacotherapeutic targets for NASH treatment.


Asunto(s)
Fosfolipasas A2 Grupo IV/antagonistas & inhibidores , Indoles/uso terapéutico , Terapia Molecular Dirigida , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/etiología , Propionatos/uso terapéutico , Animales , Modelos Animales de Enfermedad , Fosfolipasas A2 Grupo IV/fisiología , Humanos , Indoles/administración & dosificación , Indoles/farmacología , Ratones , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/enzimología , Propionatos/administración & dosificación , Propionatos/farmacología
12.
Free Radic Biol Med ; 134: 248-259, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30660502

RESUMEN

Elevated oxidative stress (OS) is widely accepted to be involved in the pathogenesis of Down syndrome (DS). However, the mechanisms underlying the elevation of OS in DS are poorly understood. Biometals, in particular copper and iron, play roles in OS. We therefore focused on biometals in the brain with DS. In this study, we analyzed the profile of elements, including biometals, in the brain of Ts1Cje mice, a widely used genetic model of DS. An inductively coupled plasma-mass spectrometry (ICP-MS)-based comparative metallomic/elementomic analysis of Ts1Cje mouse brain revealed a higher level of copper in the hippocampus and cerebral cortex, but not in the striatum, in comparison to wild-type littermates. The expression of the copper transporter CTR1, which is involved in the transport of copper into cells, was decreased in the ependymal cells of Ts1Cje mice, suggesting a decrease in the CTR1-mediated transport of copper into the ependymal cells, which excrete copper into the cerebrospinal fluid. To evaluate the pathological significance of the accumulation of copper in the brain of Ts1Cje mice, we examined the effects of a diet with a low copper content (LoCD) on the elevated lipid peroxidation, the accumulation of hyperphosphorylated tau, and some behavioral anomalies. Reducing the copper concentration in the brain by an LoCD restored the enhanced lipid peroxidation and phosphorylation of tau in the brain and reduced anxiety-like behavior, but not hyperactivity or impaired spatial leaning, in Ts1Cje mice. The findings highlight the reduction of accumulation of copper in the brain may be a novel therapeutic strategy for DS.


Asunto(s)
Ansiedad/prevención & control , Encéfalo/patología , Cobre/metabolismo , Modelos Animales de Enfermedad , Síndrome de Down/patología , Estrés Oxidativo , Animales , Ansiedad/metabolismo , Ansiedad/patología , Conducta Animal , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Proteínas Transportadoras de Cobre/metabolismo , Síndrome de Down/metabolismo , Síndrome de Down/psicología , Peroxidación de Lípido , Masculino , Ratones , Ratones Endogámicos C57BL , Fosforilación
13.
Sci Rep ; 9(1): 204, 2019 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-30659241

RESUMEN

C57BL/6J (BL6J) and C57BL/6N (BL6N) inbred substrains are most widely used to understand the pathological roles of target molecules in a variety of diseases, including non-alcoholic steatohepatitis (NASH), based on transgenic mouse technologies. There are notable differences in the metabolic phenotypes, including glucose tolerance, between the BL6J and BL6N substrains, but the phenotypic differences in NASH are still unknown. We performed a comparative analysis of the two mouse substrains to identify the pathological phenotypic differences in NASH models. In the CCl4-induced NASH model, the BL6J mice exhibited a more severe degree of oxidative stress and fibrosis in the liver than the BL6N mice. In contrast, in the high-fat diet-induced NASH model, more accumulation of hepatic triglycerides but less weight gain and liver injury were noted in the BL6J mice than in the BL6N mice. Our findings strongly suggest caution be exercised with the use of unmatched mixed genetic background C57BL6 mice for studies related to NASH, especially when generating conditional knockout C57BL6 mice.


Asunto(s)
Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/patología , Animales , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Femenino , Fibrosis , Masculino , Ratones , Ratones Endogámicos C57BL/genética , Ratones Endogámicos , Ratones Noqueados , Ratones Transgénicos , Enfermedad del Hígado Graso no Alcohólico/genética , Estrés Oxidativo/fisiología , Fenotipo , Aumento de Peso
14.
Biochem Biophys Res Commun ; 471(1): 15-20, 2016 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-26850849

RESUMEN

Group IVA phospholipase A2 (IVA-PLA2), which generates arachidonate, plays a role in inflammation. IVA-PLA2-deficiency reduced hepatotoxicity and hepatocyte cell death in mice that received a single dose of carbon tetrachloride (CCl4) without any inhibitory effects on CCl4-induced lipid peroxidation. An immunoblot analysis of extracts from wild-type mouse- and IVA-PLA2 KO mouse-derived primary hepatocytes that transiently expressed microtubule-associated protein 1 light chain 3B (LC3) revealed a higher amount of LC3-II, a typical index of autophagosome formation, in IVA-PLA2-deficient cells, suggesting the enhancement of constitutive autophagy. IVA-PLA2 may promote CCl4-induced cell death through the suppression of constitutive autophagy in hepatocytes.


Asunto(s)
Autofagia/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Fosfolipasas A2 Grupo IV/metabolismo , Hepatocitos/metabolismo , Hepatocitos/patología , Animales , Apoptosis/efectos de los fármacos , Tetracloruro de Carbono , Células Cultivadas , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Fosfolipasas A2 Grupo IV/genética , Hepatocitos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
15.
Int J Biol Sci ; 12(1): 63-71, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26722218

RESUMEN

Chronic inflammatory diseases, such as rheumatoid arthritis and periodontitis-caused bone destruction, results from an increase of bone-resorbing osteoclasts (OCs) induced by inflammation. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated that the effect of urokinase-type plasminogen activator (uPA) on inflammatory osteoclastogenesis induced by lipopolysaccharide (LPS), which is a potent stimulator of bone resorption in inflammatory diseases. We found that the uPA deficiency promoted inflammatory osteoclastogenesis and bone loss induced by LPS. We also showed that LPS induced the expression of uPA, and the uPA treatment attenuated the LPS-induced inflammatory osteoclastogenesis of RAW264.7 mouse monocyte/macrophage lineage cells. Additionally, we showed that the uPA-attenuated inflammatory osteoclastgenesis is associated with the activation of plasmin/protease-activated receptor (PAR)-1 axis by uPA. Moreover, we examined the mechanism underlying the effect of uPA on inflammatory osteoclastogenesis, and found that uPA/plasmin/PAR-1 activated the adenosine monophosphate-activated protein kinase (AMPK) pathway through Ca2+/calmodulin dependent protein kinase kinase (CaMKK) activation, and attenuated inflammatory osteoclastogenesis by inactivation of NF-κB in RAW264.7 cells. These data suggest that uPA attenuated inflammatory osteoclastogenesis through the plasmin/PAR-1/Ca2+/CaMKK/AMPK axis. Our findings may provide a novel therapeutic approach to bone loss caused by inflammatory diseases.


Asunto(s)
Quinasa de la Proteína Quinasa Dependiente de Calcio-Calmodulina/metabolismo , Fibrinolisina/metabolismo , Lipopolisacáridos/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Osteoclastos/citología , Osteoclastos/efectos de los fármacos , Receptor PAR-1/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/farmacología , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular , Ratones , Transducción de Señal/efectos de los fármacos , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo
16.
Arch Gerontol Geriatr ; 62: 118-24, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26388436

RESUMEN

BACKGROUND: Vascular dementia is related to intracranial arteriosclerosis associated with deep white matter lesions (DWMLs). DWMLs have been linked to thrombogenesis due to sustained platelet activation; therefore, an accurate hematological marker is needed. This study was done to evaluate the usefulness of a new method to examine the function of activated platelets in order to assess DWMLs associated with cognitive decline. METHODS: A total of 143 individuals (70.4 ± 6.1 years old) who underwent hospital-based health screening using head MRI were evaluated. DWLs were evaluated on T2-weighted and FLAIR images by semi-quantitatively grading them from Grade 0 (none) to Grade 3 (severe) using the Fazekas classification. Cognitive function was evaluated using the MMSE and the word fluency test. Platelet activation was assessed using fluorescence-labeled anti-human platelet monoclonal antibodies and semi-quantitatively determining PAC-1- and CD62P-positive rates by flow cytometry. RESULTS: Significant increases in hypertension and CD62P levels were observed with increasing DWML grade (2.6% in Group 0, 3.1% in Group 1, 4.1% in Group 2, and 5.0% in Group 3). CD62P levels were defined as elevated when they were above the mean+2SD of the Grade 0 group, and the odds ratio of the Grade 2+3 group was 3.03. A significant negative correlation was observed between CD62P levels and word fluency tests or the MMSE score. CONCLUSION: Elevations in CD62P levels, which reflect platelet function activation, were associated with white matter lesions accompanied by a decline in cognitive function. CD62P levels may be useful as a sensitive clinical marker for the early detection of DWMLs with cognitive decline.


Asunto(s)
Plaquetas/patología , Trastornos del Conocimiento/patología , Hipertensión/patología , Selectina-P/metabolismo , Activación Plaquetaria/fisiología , Sustancia Blanca/patología , Anciano , Cognición , Demencia Vascular , Femenino , Humanos , Arteriosclerosis Intracraneal , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Factores de Riesgo
17.
JIMD Rep ; 28: 85-93, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26545879

RESUMEN

Sandhoff disease (SD) is a lysosomal ß-hexosaminidase (Hex) deficiency involving excessive accumulation of undegraded substrates, including GM2 ganglioside, and progressive neurodegeneration. Macrophage inflammatory protein-1α (MIP-1α) is a crucial factor for microglia-mediated neuroinflammation in the onset or progression of SD. However, the transmitter-mediated production of MIP-1α in SD is still poorly understood.Extracellular nucleotides, including uridine diphosphate (UDP), leaked by either injured or damaged neuronal cells activate microglia to trigger chemotaxis, phagocytosis, macropinocytosis, and cytokine production.In this study, we demonstrated that UDP enhanced the production of MIP-1α by microglia derived from SD mice (SD-Mg), but not that from wild-type mice (WT-Mg). The UDP-induced MIP-1α production was mediated by the activation of P2Y6 receptor, ERK, and JNK. We also found the amount of dimeric P2Y6 receptor protein to have increased in SD-Mg in comparison to WT-Mg. In addition, we demonstrated that the disruption of lipid rafts enhanced the effect of UDP on MIP-1α production and the disordered maintenance of the lipid rafts in SD-Mg. Thus, the accumulation of undegraded substrates might cause the enhanced effect of UDP in SD-Mg through the increased expression of the dimeric P2Y6 receptors and the disordered maintenance of the lipid rafts. These findings provide new insights into the pathogenic mechanism and therapeutic strategies for SD.

18.
J Pharmacol Exp Ther ; 356(3): 604-14, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26699145

RESUMEN

We have previously shown that high-fat cholesterol diet (HFCD)-induced fatty liver and carbon tetrachloride (CCl4)-induced hepatic fibrosis are reduced in mice deficient in group IVA phospholipase A2 (IVA-PLA2), which plays a role in inflammation. We herein demonstrate the beneficial effects of ASB14780 (3-[1-(4-phenoxyphenyl)-3-(2-phenylethyl)-1H-indol-5-yl]propanoic acid 2-amino-2-(hydroxymethyl)propane-1,3-diol salt), an orally active IVA-PLA2 inhibitor, on the development of fatty liver and hepatic fibrosis in mice. The daily coadministration of ASB14780 markedly ameliorated liver injury and hepatic fibrosis following 6 weeks of treatment with CCl4. ASB14780 markedly attenuated the CCl4-induced expression of smooth muscle α-actin (α-SMA) protein and the mRNA expression of collagen 1a2, α-SMA, and transforming growth factor-ß1 in the liver, and inhibited the expression of monocyte/macrophage markers, CD11b and monocyte chemotactic protein-1, while preventing the recruitment of monocytes/macrophages to the liver. Importantly, ASB14780 also reduced the development of fibrosis even in matured hepatic fibrosis. Additionally, ASB14780 also reduced HFCD-induced lipid deposition not only in the liver, but also in already established fatty liver. Furthermore, treatment with ASB14780 suppressed the HFCD-induced expression of lipogenic mRNAs. The present findings suggest that an IVA-PLA2 inhibitor, such as ASB14780, could be useful for the treatment of nonalcoholic fatty liver diseases, including fatty liver and hepatic fibrosis.


Asunto(s)
Fosfolipasas A2 Grupo IV/antagonistas & inhibidores , Indoles/administración & dosificación , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Inhibidores de Fosfolipasa A2/administración & dosificación , Propionatos/administración & dosificación , Administración Oral , Animales , Inhibidores Enzimáticos/administración & dosificación , Fosfolipasas A2 Grupo IV/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/enzimología
19.
Sci Rep ; 4: 5967, 2014 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-25095732

RESUMEN

Renal fibrosis is the final common pathway of a wide variety of chronic kidney diseases. Myofibroblast formation via the differentiation of from tissue-resident fibroblasts and bone marrow-derived mesenchymal stem cells (MSCs), and epithelial-to-mesenchymal transition (EMT) is known to play a pivotal role in the development of renal fibrosis. However, the detailed mechanisms underlying this disorder remain unclear. We herein investigated the role of alpha 2-antiplasmin (α2AP) in myofibroblast formation and the development of renal fibrosis. We observed the development of renal fibrosis using unilateral ureteral obstruction (UUO). α2AP had accumulated in the UUO-induced obstructed kidneys and α2AP deficiency attenuated UUO-induced renal fibrosis in mice. The degree of myofibroblast formation in the obstructed kidneys of α2AP(-/-) mice was less than that in α2AP(+/+) mice. In vitro, α2AP induced myofibroblast formation in renal tubular epithelial cells (RTECs), renal fibrosblasts, and bone marrow-derived mesenchymal stem cells (MSCs). α2AP also induced the production of TGF-ß, which is known to be a key regulator of myofibroblast formation and fibrosis. α2AP-induced the TGF-ß production was significantly reduced by SP600125, c-Jun N-terminal kinase (JNK) specific inhibitor. Our findings suggest that α2AP induces myofibroblast formation in the obstructed kidneys, and mediates the development of renal fibrosis.


Asunto(s)
Riñón/metabolismo , Miofibroblastos/metabolismo , Insuficiencia Renal/genética , Factor de Crecimiento Transformador beta/genética , Obstrucción Ureteral/genética , alfa 2-Antiplasmina/genética , Animales , Antracenos/farmacología , Diferenciación Celular , Células Epiteliales/metabolismo , Células Epiteliales/patología , Fibrosis , Regulación de la Expresión Génica , Riñón/patología , MAP Quinasa Quinasa 4/antagonistas & inhibidores , MAP Quinasa Quinasa 4/genética , MAP Quinasa Quinasa 4/metabolismo , Masculino , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/patología , Ratones , Ratones Noqueados , Miofibroblastos/patología , Cultivo Primario de Células , Inhibidores de Proteínas Quinasas/farmacología , Insuficiencia Renal/complicaciones , Insuficiencia Renal/metabolismo , Insuficiencia Renal/patología , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Uréter/metabolismo , Uréter/patología , Obstrucción Ureteral/complicaciones , Obstrucción Ureteral/metabolismo , Obstrucción Ureteral/patología , alfa 2-Antiplasmina/deficiencia
20.
PLoS One ; 9(5): e97947, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24874880

RESUMEN

BACKGROUND: The α2-antiplasmin (α2AP) protein is known to be a principal physiological inhibitor of plasmin, and is expressed in various part of the brain, including the hippocampus, cortex, hypothalamus and cerebellum, thus suggesting a potential role for α2AP in brain functions. However, the involvement of α2AP in brain functions is currently unclear. OBJECTIVES: The goal of this study was to investigate the effects of the deletion of the α2AP gene on the behavior of mice. METHODS: The motor function was examined by the wire hang test and rotarod test. To evaluate the cognitive function, a repeated rotarod test, Y-maze test, Morris water maze test, passive or shuttle avoidance test and fear conditioning test were performed. An open field test, dark/light transition test or tail suspension test was performed to determine the involvement of α2AP in anxiety or depression-like behavior. RESULTS AND CONCLUSIONS: The α2AP knockout (α2AP-/-) mice exhibited impaired motor function compared with α2AP+/+ mice. The α2AP-/- mice also exhibited impairments in motor learning, working memory, spatial memory and fear conditioning memory. Furthermore, the deletion of α2AP induced anxiety-like behavior, and caused an anti-depression-like effect in tail suspension. Therefore, our findings suggest that α2AP is a crucial mediator of motor function, cognitive function, anxiety-like behavior and depression-like behavior, providing new insights into the role of α2AP in the brain functions.


Asunto(s)
Conducta Animal , Eliminación de Gen , Estudios de Asociación Genética , alfa 2-Antiplasmina/genética , Animales , Ansiedad/genética , Cognición , Depresión/genética , Aprendizaje por Laberinto , Memoria a Corto Plazo , Ratones , Ratones Noqueados , Actividad Motora/genética , Memoria Espacial
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