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1.
Acta Neuropathol ; 147(1): 94, 2024 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833073

RESUMEN

A recent large genome-wide association study has identified EGFR (encoding the epidermal growth factor EGFR) as a new genetic risk factor for late-onset AD. SHIP2, encoded by INPPL1, is taking part in the signalling and interactome of several growth factor receptors, such as the EGFR. While INPPL1 has been identified as one of the most significant genes whose RNA expression correlates with cognitive decline, the potential alteration of SHIP2 expression and localization during the progression of AD remains largely unknown. Here we report that gene expression of both EGFR and INPPL1 was upregulated in AD brains. SHIP2 immunoreactivity was predominantly detected in plaque-associated astrocytes and dystrophic neurites and its increase was correlated with amyloid load in the brain of human AD and of 5xFAD transgenic mouse model of AD. While mRNA of INPPL1 was increased in AD, SHIP2 protein undergoes a significant solubility change being depleted from the soluble fraction of AD brain homogenates and co-enriched with EGFR in the insoluble fraction. Using FRET-based flow cytometry biosensor assay for tau-tau interaction, overexpression of SHIP2 significantly increased the FRET signal while siRNA-mediated downexpression of SHIP2 significantly decreased FRET signal. Genetic association analyses suggest that some variants in INPPL1 locus are associated with the level of CSF pTau. Our data support the hypothesis that SHIP2 is an intermediate key player of EGFR and AD pathology linking amyloid and tau pathologies in human AD.


Asunto(s)
Enfermedad de Alzheimer , Encéfalo , Progresión de la Enfermedad , Receptores ErbB , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Anciano , Anciano de 80 o más Años , Animales , Femenino , Humanos , Masculino , Ratones , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Encéfalo/patología , Encéfalo/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Expresión Génica , Ratones Transgénicos , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas/metabolismo , Solubilidad , Proteínas tau/metabolismo , Proteínas tau/genética
2.
Ginekol Pol ; 2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38334335

RESUMEN

OBJECTIVES: We aimed to evaluate feto-maternal blood flow parameters using Doppler ultrasonography (USG) in pregnant women with intrahepatic cholestasis of pregnancy (ICP) and the effect of ursodeoxycholic acid (UDCA) treatment on these parameters. MATERIAL AND METHODS: This prospective cohort study was performed at Dr. Sami Ulus Women's and Children's Health Teaching and Research Hospital, in Turkey between September 2022 and February 2023. Sixty pregnant women, 30 with ICP disease and 30 healthy women were included in the study. Obstetric Doppler parameters were measured by USG at diagnosis and after 48 hours of UDCA treatment for the ICP group. RESULTS: The obstetric Doppler parameters did not significantly differ in the ICP group and the healthy control group. The Doppler findings were similar after UDCA treatment in the ICP group. Gestational week at delivery and birth weight were lower in the ICP group in our study. CONCLUSIONS: We demonstrated that pregnant women with ICP had similar obstetric Doppler parameters when compared with healthy pregnant women and that the UDCA agent used for treatment of ICP disease did not affect these parameters.

3.
J Biomol Struct Dyn ; 41(7): 2804-2822, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-35179080

RESUMEN

In this paper, the asymmetric-Schiff base 2-(4-(2-hydroxybenzylideneamino)benzylideneamino)benzoic acid (SB-2) was newly synthesized and characterized by various spectroscopic methods. The interaction of SB-2 with calf thymus DNA was investigated by UV-vis, fluorescence spectroscopy and molecular docking methods. It was determined that SB-2 effectively binds to DNA via the intercalation mode. DNA electrophoretic mobility experiments displayed that topoisomerase IIα could not cleave pBR322 plasmid DNA in the presence of SB-2, confirming that the Schiff base acts as a topo II suppressor. In the molecular docking studies, SB-2 was found to show an affinity for both the DNA-topoisomerase IIα complex and the DNA. In vitro antiproliferative activity of SB-2 was screened against HT-29 (colorectal) and HeLa (cervical) human tumor cell lines by MTT assay. SB-2 diminished the cell viability in a concentration- and incubation time-dependent manner. The ability of SB-2 to measure DNA damage in tumor cells was evaluated with cytokinesis-block micronucleus assay after incubation 24 h and 48 h. Light and scanning electron microscopy experiments of tumor cells demonstrated an incubation time-dependent increase in the proportion of apoptotic cells (nuclear condensation and apoptotic bodies) suggesting that autophagy and apoptosis play a role in the death of cells. Based on the obtained results, it may be considered that SB-2 is a candidate for DNA-targeting antitumor drug.Communicated by Ramaswamy H. Sarma.


Asunto(s)
ADN , Bases de Schiff , Humanos , Simulación del Acoplamiento Molecular , Bases de Schiff/química , ADN/química , Línea Celular Tumoral
4.
Z Geburtshilfe Neonatol ; 226(6): 384-390, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36216347

RESUMEN

OBJECTIVE: We aimed to examine the predictive and prognostic value of plasma zonulin for gestational diabetes mellitus (GDM) in women at 24-28 weeks of gestation. METHODS: This retrospective study was carried out with pregnant women with GDM (n=98) and normal glucose tolerance (control group) (n=132). GDM was diagnosed according to American Diabetes Association (ADA) criteria with a one-step 75-g OGTT at 24-28 gestational weeks. Their serum zonulin levels measured during one-step 75-g OGTT and perinatal outcomes were compared, and the cut-off value of plasma zonulin for the prediction of GDM was calculated with receiver operating characteristic curve analysis. RESULTS: Plasma zonulin level was significantly higher in women with GDM compared to controls (28.8±24.9 and 7.3±11.3 ng/mL, respectively). According to logistic regression analysis, plasma zonulin levels and GDM were statistically significant. The plasma zonulin cut-off value was>45.2 ng/mL. The rate of cesarean section, the rate of meconium in the amniotic fluid, and the need for admission to the neonatal intensive care unit significantly differed between women with GDM and controls. CONCLUSION: In pregnant women with GDM, plasma zonulin increases, and with the cut-off level of>45.2 ng/mL, it can predict GDM with values of sensitivity and specificity levels significantly higher in pregnant women with GDM, suggesting that it can be used as a tool for its screening and early diagnosis.


Asunto(s)
Diabetes Gestacional , Embarazo , Recién Nacido , Femenino , Humanos , Diabetes Gestacional/diagnóstico , Pronóstico , Cesárea , Estudios Retrospectivos
5.
Artículo en Inglés | MEDLINE | ID: mdl-34886280

RESUMEN

We investigated the question of how serum zonulin levels change in intrahepatic cholestasis of pregnancy (ICP) and gestational diabetes mellitus (GDM) and, in the case of the coexistence of ICP and GDM, evaluated the eventual increase in zonulin plasmatic levels. Participants were enrolled for the study between 25 February 2021 and 20 August 2021. The prospective case-control study included: group 1 of 95 pregnant women diagnosed with ICP; group 2 of 110 pregnant women diagnosed with GDM; group 3 of 16 women diagnosed with both GDM and ICP; group 4 of 136 healthy pregnant women as the control group. The groups were compared in terms of age, body mass index (BMI), gravidity, parity, gestational week of delivery, plasma zonulin levels, delivery type, birth weight, first- and fifth-minute APGAR scores, newborn intensive care unit (NICU) admission, and meconium staining of amniotic fluid parameters. The results suggested that the plasma zonulin levels of ICP (group 1), GDM (group 2), and GDM with ICP (group 3) patients were higher than those of the healthy pregnant women of group 4 (p < 0.001). Among the patient groups, the highest median plasma zonulin levels were found in group 3 (110.33 ng/mL). Zonulin levels were also associated with the severity of ICP and adverse pregnancy outcomes. High serum zonulin levels were related to GDM, ICP, and adverse perinatal outcomes. The coexistence of GDM and ICP led to higher serum zonulin concentrations.


Asunto(s)
Colestasis Intrahepática , Diabetes Gestacional , Haptoglobinas/análisis , Complicaciones del Embarazo , Precursores de Proteínas/sangre , Estudios de Casos y Controles , Femenino , Humanos , Recién Nacido , Embarazo , Resultado del Embarazo
6.
Brain Behav ; 11(8): e2292, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34291595

RESUMEN

BACKGROUND: Non-motor symptoms are well established phenotypic components of adult-onset idiopathic, isolated, focal cervical dystonia (AOIFCD). However, improved understanding of their clinical heterogeneity is needed to better target therapeutic intervention. Here, we examine non-motor phenotypic features to identify possible AOIFCD subgroups. METHODS: Participants diagnosed with AOIFCD were recruited via specialist neurology clinics (dystonia wales: n = 114, dystonia coalition: n = 183). Non-motor assessment included psychiatric symptoms, pain, sleep disturbance, and quality of life, assessed using self-completed questionnaires or face-to-face assessment. Both cohorts were analyzed independently using Cluster, and Bayesian multiple mixed model phenotype analyses to investigate the relationship between non-motor symptoms and determine evidence of phenotypic subgroups. RESULTS: Independent cluster analysis of the two cohorts suggests two predominant phenotypic subgroups, one consisting of approximately a third of participants in both cohorts, experiencing increased levels of depression, anxiety, sleep impairment, and pain catastrophizing, as well as, decreased quality of life. The Bayesian approach reinforced this with the primary axis, which explained the majority of the variance, in each cohort being associated with psychiatric symptomology, and also sleep impairment and pain catastrophizing in the Dystonia Wales cohort. CONCLUSIONS: Non-motor symptoms accompanying AOIFCD parse into two predominant phenotypic sub-groups, with differences in psychiatric symptoms, pain catastrophizing, sleep quality, and quality of life. Improved understanding of these symptom groups will enable better targeted pathophysiological investigation and future therapeutic intervention.


Asunto(s)
Trastornos Distónicos , Tortícolis , Adulto , Teorema de Bayes , Humanos , Fenotipo , Calidad de Vida , Tortícolis/epidemiología
7.
Front Neurol ; 12: 610330, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33643196

RESUMEN

Adult hippocampal neurogenesis (AHN) has been widely confirmed in mammalian brains. A growing body of evidence points to the fact that AHN sustains hippocampal-dependent functions such as learning and memory. Impaired AHN has been reported in post-mortem human brain hippocampus of Alzheimer's disease (AD) and is considered to contribute to defects in learning and memory. Neurofibrillary tangles (NFTs) and amyloid plaques are the two key neuropathological hallmarks of AD. NFTs are composed of abnormal tau proteins accumulating in many brain areas during the progression of the disease, including in the hippocampus. The physiological role of tau and impact of tau pathology on AHN is still poorly understood. Modifications in AHN have also been reported in some tau transgenic and tau-deleted mouse models. We present here a brief review of advances in the relationship between development of tau pathology and AHN in AD and what insights have been gained from studies in tau mouse models.

8.
Front Mol Neurosci ; 13: 106, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32765217

RESUMEN

Alzheimer's disease (AD) is characterized by the accumulation in the brain of intraneuronal aggregates of abnormally and hyperphosphorylated tau proteins and of extracellular deposits of amyloid-ß surrounded by dystrophic neurites. Numerous experimental models have shown that tau pathology develops in the brain after intracerebral injection of brain homogenates or pathological tau [paired helical filaments (PHF)-tau)] from AD brains. Further investigations are however necessary to identify or exclude potential extracerebral routes of tau pathology transmission, e.g., through the intravascular route. In this study, we have analyzed the effect of intravenous injection of PHF-tau proteins from AD brains on the formation of tau and amyloid pathologies in the brain of wild-type (WT) mice and of 5XFAD mice (an amyloid model). We observed that 5XFAD mice with a disrupted blood-brain barrier showed increased plaque-associated astrogliosis, microgliosis, and increased deposits of Aß40 and Aß42 after intravenous injection of PHF-tau proteins. In addition, an increased phosphotau immunoreactivity was observed in plaque-associated dystrophic neurites. These results suggest that blood products contaminated by PHF-tau proteins could potentially induce an exacerbation of neuroinflammation and AD pathologies.

9.
Turk J Pediatr ; 62(4): 652-656, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32779419

RESUMEN

BACKGROUND: The recently described FBXL4-related encephalomyopathic mitochondrial DNA depletion syndrome 13 (MTDPS13) manifests with severe encephalopathy, early-onset lactic acidosis, hypotonia, developmental delay and feeding difficulty. Less than 100 cases with FBXL4-related MTDPS13 and 47 pathogenic mutations in the FBXL4 gene have been identified thus far. Here, we describe a patient diagnosed with MTDPS13 with two novel variants of the FBXL4 gene. CASE: A 51-day-old male was admitted with the complaint of bloody stool. His physical examination revealed facial dysmorphic features, developmental delay and truncal hypotonia with lack of head control. Laboratory investigations showed anemia, neutropenia, metabolic acidosis with hyperlactatemia, elevated fumaric acid, 2-ketoglutaric acid in urine and elevated alanine level in plasma which were consistent with mitochondrial dysfunction. Brain magnetic resonance imaging (MRI) showed large ventricles, thin corpus callosum and poor myelination. Drug-resistant epilepsy developed during the clinical follow-up. Ketogenic diet was initiated for intractable epilepsy; which was then interrupted due to severe metabolic acidosis. Compound heterozygous pathogenic variants were detected in the FBXL4 gene [p.Gly258* (c.772G > T, Exon 5)/p.Trp354Ser (c.1061G > C, Exon 6)] with whole-exome sequencing. CONCLUSION: We detected two novel variants of the FBXL4 gene. To the best of our knowledge, this is the first case in the literature that presented with gastrointestinal bleeding as an encephalomyopathic form of mitochondrial DNA depletion syndromes and for whom ketogenic diet was initiated due to intractable epilepsy, which was not reported in previous cases.


Asunto(s)
Proteínas F-Box , Encefalomiopatías Mitocondriales , ADN Mitocondrial , Proteínas F-Box/genética , Humanos , Masculino , Mutación , Ubiquitina-Proteína Ligasas/genética
11.
Acta Neuropathol Commun ; 8(1): 79, 2020 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-32493451

RESUMEN

Synaptojanin 1 (SYNJ1) is a brain-enriched lipid phosphatase critically involved in autophagosomal/endosomal trafficking, synaptic vesicle recycling and metabolism of phosphoinositides. Previous studies suggest that SYNJ1 polymorphisms have significant impact on the age of onset of Alzheimer's disease (AD) and that SYNJ1 is involved in amyloid-induced toxicity. Yet SYNJ1 protein level and cellular localization in post-mortem human AD brain tissues have remained elusive. This study aimed to examine whether SYNJ1 localization and expression are altered in post-mortem AD brains. We found that SYNJ1 is accumulated in Hirano bodies, plaque-associated dystrophic neurites and some neurofibrillary tangles (NFTs). SYNJ1 immunoreactivity was higher in neurons and in the senile plaques in AD patients carrying one or two ApolipoproteinE (APOE) ε4 allele(s). In two large cohorts of APOE-genotyped controls and AD patients, SYNJ1 transcripts were significantly increased in AD temporal isocortex compared to control. There was a significant increase in SYNJ1 transcript in APOEε4 carriers compared to non-carriers in AD cohort. SYNJ1 was systematically co-enriched with PHF-tau in the sarkosyl-insoluble fraction of AD brain. In the RIPA-insoluble fraction containing protein aggregates, SYNJ1 proteins were significantly increased and observed as a smear containing full-length and cleaved fragments in AD brains. In vitro cleavage assay showed that SYNJ1 is a substrate of calpain, which is highly activated in AD brains. Our study provides evidence of alterations in SYNJ1 mRNA level and SYNJ1 protein degradation, solubility and localization in AD brains.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Encéfalo/patología , Monoéster Fosfórico Hidrolasas/metabolismo , Agregación Patológica de Proteínas/patología , Anciano , Apolipoproteínas E/genética , Encéfalo/metabolismo , Calpaína/metabolismo , Células HEK293 , Humanos , Neuronas/metabolismo , Neuronas/patología , Proteínas tau/metabolismo
12.
Acta Neuropathol ; 139(4): 773-789, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31925534

RESUMEN

Genome-wide association studies (GWAS) have identified PICALM as one of the most significant susceptibility loci for late-onset Alzheimer's disease (AD) after APOE and BIN1. PICALM is a clathrin-adaptor protein and plays critical roles in clathrin-mediated endocytosis and in autophagy. PICALM modulates brain amyloid ß (Aß) pathology and tau accumulation. We have previously reported that soluble PICALM protein level is reduced in correlation with abnormalities of autophagy markers in the affected brain areas of neurodegenerative diseases including AD, sporadic tauopathies and familial cases of frontotemporal lobar degeneration with tau-immunoreactive inclusions (FTLD-tau) with mutations in the microtubule-associated protein tau (MAPT) gene. It remains unclarified whether in vivo PICALM reduction could either trigger or influence tau pathology progression in the brain. In this study, we confirmed a significant reduction of soluble PICALM protein and autophagy deficits in the post-mortem human brains of FTLD-tau-MAPT (P301L, S364S and L266V). We generated a novel transgenic mouse line named Tg30xPicalm+/- by crossing Tg30 tau transgenic mice with Picalm-haploinsufficient mice to test whether Picalm reduction may modulate tau pathology. While Picalm haploinsufficiency did not lead to any motor phenotype or detectable tau pathology in mouse brains, Tg30xPicalm+/- mice developed markedly more severe motor deficits than Tg30 by the age of 9 months. Tg30xPicalm+/- had significantly higher pathological tau levels in the brain, an increased density of neurofibrillary tangles compared to Tg30 mice and increased abnormalities of autophagy markers. Our results demonstrate that Picalm haploinsufficiency in transgenic Tg30 mice significantly aggravated tau pathologies and tau-mediated neurodegeneration, supporting a role for changes in Picalm expression as a risk/sensitizing factor for development of tau pathology and as a mechanism underlying the AD risk associated to PICALM.


Asunto(s)
Proteínas de Ensamble de Clatrina Monoméricas/genética , Tauopatías/genética , Tauopatías/patología , Animales , Encéfalo/patología , Modelos Animales de Enfermedad , Femenino , Demencia Frontotemporal/metabolismo , Haploinsuficiencia , Humanos , Masculino , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Proteínas de Ensamble de Clatrina Monoméricas/metabolismo , Tauopatías/metabolismo , Proteínas tau/genética
13.
Neurobiol Aging ; 81: 200-212, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31306814

RESUMEN

Human tauopathies are neurodegenerative diseases with accumulation of abnormally phosphorylated and aggregated tau proteins forming neurofibrillary tangles. We investigated the development of tau pathology in aged cat brains as a model of neurofibrillary tangle formation occurring spontaneously during aging. In 4 of 6 cats aged between 18 and 21 years, we found a somatodendritic accumulation of phosphorylated and aggregated tau in neurons and oligodendrocytes. Two of these 4 cats had no amyloid immunoreactivity. These tau inclusions were mainly composed of 4R tau isoforms and straight filaments and colocalized with the active form of the glycogen synthase kinase-3 (GSK3). Cat brains with a tau pathology showed a significant cortical atrophy and neuronal loss. We demonstrate in this study the presence of a tau pathology in aged cat brains that develop independently of amyloid deposits. The colocalization of the active form of the GSK3 with tau inclusions as observed in human tauopathies suggests that this kinase could be responsible for the abnormal tau phosphorylation observed in aged cat brains, representing a mechanism of tau pathology development shared between a naturally occurring tauopathy in aged cats and human tauopathies.


Asunto(s)
Envejecimiento/metabolismo , Encéfalo/metabolismo , Tauopatías/etiología , Proteínas tau/metabolismo , Animales , Encéfalo/patología , Gatos , Glucógeno Sintasa Quinasa 3 , Humanos , Ovillos Neurofibrilares , Neuronas/metabolismo , Fosforilación , Placa Amiloide , Tauopatías/metabolismo , Tauopatías/patología
14.
J Biol Inorg Chem ; 24(3): 365-376, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30895485

RESUMEN

One iron(III) and two manganese(III) complexes based on thiosemicarbazone were synthesized and characterized using analytical and spectroscopic data. The crystallographic analysis showed the square pyramid structures of the complexes. Electronic spectra analysis was performed to determine the nature of the interaction between the complexes and calf thymus DNA (CT-DNA). DNA cleavage activities of the complexes were examined by gel electrophoresis (pBR322 DNA). The cytotoxicity of the complexes was determined against human cervical carcinoma (HeLa) and human colorectal adenocarcinoma (HT-29) cell lines by MTT assay. The results indicated that complex Fe1 is bound to CT-DNA via the intercalation mode, while complexes Mn1 and Mn2 are bound to CT-DNA via groove binding and/or electrostatic interactions rather than the intercalation mode. In addition, they showed good binding activity, which followed the order of Fe1 > Mn2 > Mn1. Complexes were found to promote the cleavage of DNA from supercoiled form (SC, Form I) to nicked circular form (NC, Form II) without concurrent formation of Form III, revealing the single-strand DNA cleavage. No significant cleavage was found in the presence of Mn1 and Mn2; however, it was observed at 2000 and 3000 µM concentrations of Fe1. The ability of Fe1 to cleave DNA was greater than that of other complexes and these results are in conformity with their DNA-binding affinities. Cytotoxicity determination tests revealed that the complex Fe1 on HeLa and HT-29 cells exhibited a higher anti-proliferative effect than Mn1 and Mn2 (Fe1 > Mn2 > Mn1). These studies suggested that the complex Fe1 could be a good candidate as a chemotherapeutic drug targeting DNA.


Asunto(s)
Antineoplásicos/farmacología , Complejos de Coordinación/farmacología , División del ADN/efectos de los fármacos , ADN/efectos de los fármacos , Tiosemicarbazonas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Bovinos , Línea Celular Tumoral , Complejos de Coordinación/síntesis química , Complejos de Coordinación/química , ADN/química , Humanos , Sustancias Intercalantes/síntesis química , Sustancias Intercalantes/química , Sustancias Intercalantes/farmacología , Hierro/química , Manganeso/química , Estructura Molecular , Tiosemicarbazonas/síntesis química , Tiosemicarbazonas/química
15.
Neurobiol Dis ; 127: 131-141, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30818066

RESUMEN

Impaired adult hippocampal neurogenesis has been reported as a feature of Alzheimer's disease and other tauopathies and might contribute to defects in learning and memory in these diseases. To assess the interference of tau pathology, a common key-lesion in these diseases, with adult hippocampal neurogenesis we analyzed adult neurogenesis in the hippocampal dentate gyrus in wild-type mice, Tg30 mice expressing a FTDP-17 mutant tau and the same Tg30 mice deficient for mouse tau (Tg30/tauKO). The volume of the granular layer, the number of granule cells and of neuronal precursors expressing the immature markers DCX or 3R-tau were analyzed in the dentate gyrus (DG) using unbiased stereological methods. The co-localization of neurogenic markers with the human mutant tau was also analyzed. We observed a significant reduction of the volume of the granular layer and of granule cells number in mutant tau Tg30 mice, but not in Tg30/tauKO mice. The number of neuronal precursors expressing the immature markers DCX or 3R-tau (the latter only expressed in wild-type and Tg30 mice) and the number of cells expressing the proliferation marker Ki-67 in the neurogenic subgranular zone of the DG was reduced in Tg30 but not in Tg30/tauKO mice. The density of phosphotau positive cells in the DG and the level of soluble human phosphotau was lower in Tg30/tauKO compared to Tg30 mice. The human mutant tau was expressed in mature granule cells in Tg30 and Tg30/tauKO mice but was not expressed in Sox2 positive neural stem cells and in DCX positive neuronal precursors/immature newborn neurons. These results demonstrate an impairment of adult hippocampal neurogenesis in a FTDP-17 mutant tau mice resulting from a decrease of proliferation affecting the pool of neuronal precursors. The mutant tau was not expressed in precursors cells in these mutant tau mice, suggesting that this neurogenic defect is cell non-autonomous. Interestingly, expression of endogenous wild-type tau in mature granule cells was necessary to observe this toxic effect of human mutant tau, since this impaired adult neurogenesis was rescued by lowering tau expression in Tg30/tauKO mice. These observations suggest that development of tau pathology in granule cells of the dentate gyrus is responsible for reduction of adult hippocampal neurogenesis also in human tauopathies by impairing proliferation of neuronal precursors, and that reduction of tau expression might be an approach to rescue this impairment.


Asunto(s)
Hipocampo/metabolismo , Neurogénesis/genética , Neuronas/metabolismo , Tauopatías/metabolismo , Proteínas tau/metabolismo , Animales , Proliferación Celular/fisiología , Proteína Doblecortina , Hipocampo/patología , Memoria/fisiología , Ratones , Ratones Transgénicos , Células-Madre Neurales/metabolismo , Neuronas/patología , Tauopatías/genética , Tauopatías/patología , Proteínas tau/genética
16.
Acta Neuropathol ; 137(3): 397-412, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30599077

RESUMEN

Neuropathological analysis in Alzheimer's disease (AD) and experimental evidence in transgenic models overexpressing frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP-17) mutant tau suggest that amyloid-ß pathology enhances the development of tau pathology. In this work, we analyzed this interaction independently of the overexpression of an FTDP-17 mutant tau, by analyzing tau pathology in wild-type (WT), 5xFAD, APP-/- and tau-/- mice after stereotaxic injection in the somatosensory cortex of short-length native human AD-PHF. Gallyas and phosphotau-positive tau inclusions developed in WT, 5xFAD, and APP-/- but not in tau-/- mice. Ultrastructural analysis demonstrated their intracellular localization and that they were composed of straight filaments. These seeded tau inclusions were composed only of endogenous murine tau exhibiting a tau antigenic profile similar to tau aggregates in AD. Insoluble tau level was higher and ipsilateral anteroposterior and contralateral cortical spreading of tau inclusions was more important in AD-PHF-injected 5xFAD mice than in WT mice. The formation of large plaque-associated dystrophic neurites positive for oligomeric and phosphotau was observed in 5xFAD mice injected with AD-PHF but never in control-injected or in non-injected 5xFAD mice. An increased level of the p25 activator of CDK5 kinase was found in AD-PHF-injected 5xFAD mice. These data demonstrate in vivo that the presence of Aß pathology enhances experimentally induced tau seeding of endogenous, wild-type tau expressed at physiological level, and demonstrate the fibrillar nature of heterotopically seeded endogenous tau. These observations further support the hypothesis that Aß enhances tau pathology development in AD through increased pathological tau spreading.


Asunto(s)
Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Ovillos Neurofibrilares/patología , Proteínas tau/metabolismo , Animales , Humanos , Ratones , Ratones Noqueados
17.
J Obstet Gynaecol Res ; 44(9): 1712-1718, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29978524

RESUMEN

AIM: Intrahepatic cholestasis of pregnancy (ICP) is a unique hepatic disorder of pregnancy and is related to adverse maternal and perinatal outcomes. The pathogenesis of the disease is not clear and appears to be multifactorial. There is increasing evidence that vitamin D (Vit D) plays a role in hepatobiliary homeostasis and in various liver diseases. We aimed to investigate the association between serum Vit D level and ICP. METHODS: A total of 40 pregnant women with ICP and 40 healthy pregnant women were included in this controlled cross-sectional study. Their demographic characteristics, including age, body mass index (BMI), gestational week, gravidity and parity, and laboratory parameters, including 25(OH) Vit D3 levels, liver function tests, fasting and postprandial bile acid concentrations, were recorded. Gestational age at delivery, birth weight (BW), neonatal intensive care unit (NICU) admission, meconium staining of amniotic fluid and appearance pulse grimace activity respiration (APGAR) score at 5 min were obtained from medical records for assessment of perinatal outcomes. RESULTS: There was no significant difference between groups in terms of demographic characteristics. The mean serum 25(OH) Vit D3 level was significantly lower in pregnant women with ICP compared to control pregnant women (8.6 ± 4.9, 11.3 ± 6.1; P =0.033), and it was significantly lower in severe disease than mild disease (6.9 ± 2.1, 10.3 ± 6.2, respectively; P =0.029). We also found that lower serum 25(OH) Vit D3 levels were significantly and inversely correlated with fasting and postprandial bile acid levels. However, in subgroup analyses in ICP pregnant women, there was no difference in mean 25(OH) Vit D3 levels for women with or without perinatal complications. CONCLUSION: Our study suggests that low levels of 25(OH) Vit D3 were associated with ICP disease and its severity. However, further larger studies are needed to evaluate the effect of Vit D in the pathogenesis and outcome of the disease.


Asunto(s)
Colestasis Intrahepática/sangre , Hidroxicolecalciferoles/sangre , Complicaciones del Embarazo/sangre , Adulto , Estudios Transversales , Femenino , Humanos , Embarazo , Adulto Joven
18.
Neurobiol Aging ; 68: 68-75, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29729423

RESUMEN

In Alzheimer's disease, many indicators point to a central role for poor axonal transport, but the potential for stimulating axonal transport to alleviate the disease remains largely untested. Previously, we reported enhanced anterograde axonal transport of mitochondria in 8- to 11-month-old MAPTP301L knockin mice, a genetic model of frontotemporal dementia with parkinsonism-17T. In this study, we further characterized the axonal transport of mitochondria in younger MAPTP301L mice crossed with the familial Alzheimer's disease model, TgCRND8, aiming to test whether boosting axonal transport in young TgCRND8 mice can alleviate axonal swelling. We successfully replicated the enhancement of anterograde axonal transport in young MAPTP301L/P301L knockin animals. Surprisingly, we found that in the presence of the amyloid precursor protein mutations, MAPTP301L/P3101L impaired anterograde axonal transport. The numbers of plaque-associated axonal swellings or amyloid plaques in TgCRND8 brains were unaltered. These findings suggest that amyloid-ß promotes an action of mutant tau that impairs axonal transport. As amyloid-ß levels increase with age even without amyloid precursor protein mutation, we suggest that this rise could contribute to age-related decline in frontotemporal dementia.


Asunto(s)
Envejecimiento/genética , Envejecimiento/fisiología , Péptidos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Transporte Axonal/genética , Demencia Frontotemporal/etiología , Demencia Frontotemporal/genética , Estudios de Asociación Genética , Variación Genética , Mutación , Proteínas tau/genética , Envejecimiento/metabolismo , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Animales , Transporte Axonal/fisiología , Encéfalo/metabolismo , Encéfalo/patología , Modelos Animales de Enfermedad , Demencia Frontotemporal/metabolismo , Demencia Frontotemporal/patología , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/genética , Mitocondrias/metabolismo , Placa Amiloide/metabolismo , Proteínas tau/metabolismo
19.
J Matern Fetal Neonatal Med ; 31(11): 1477-1482, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28462673

RESUMEN

PURPOSE: The aim of our study was to evaluate the oxidative stress (OS) in pregnant women with intrahepatic cholestasis of pregnancy (ICP) by evaluating thiol/disulphide homeostasis using an alternative technique. METHODS: A total of 57 pregnant women with ICP were compared with 50 gestational age and body mass index matched controls. A recently defined method was used for the measurement of plasma native-total thiol and disulphide levels. The independent two-sample t test, Mann-Whitney-U test, Chi-square test, binary logistic regression with backward elimination and receiver operating characteristic (ROC) curve was performed for statistical analyses. RESULTS: Pregnant women with ICP (n = 57) versus controls (n = 50) had significantly lower serum levels of native thiol (233.8 ± 47.4 µmol/L vs. 308.5 ± 51.7 µmol/L, p < .001), total thiol (258.4 ± 46.5 µmol/L vs. 328.0 ± 52.0 µmol/L, p < .001) and higher levels of disulphide (12.3 ± 3.6 µmol/L vs. 9.7 ± 3.4 µmol/L, p < .001). Binary logistic regression showed that the most important variables related to ICP were native thiol and total thiol. According to the ROC curve, the optimal cut-off level for native thiol was 280.0 µmol/L (sensitivity: 86%, specificity: 84.2%, area under the curve (AUC):0.896, 95% CI: 0.831-0.962, p < .001), and the optimal cut-off level for total thiol was 300.0 µmol/L (sensitivity: 86%, specificity: 80.7%, AUC: 0.883, 95% CI: 0.815-0.951, p < .001). CONCLUSIONS: To our knowledge, this is the first study in the literature exploring thiol/disulphide balance in ICP. We found that thiol/disulphide balance indicate OS in pregnant woman with ICP.


Asunto(s)
Análisis Químico de la Sangre/métodos , Colestasis Intrahepática/sangre , Disulfuros/sangre , Estrés Oxidativo , Complicaciones del Embarazo/sangre , Compuestos de Sulfhidrilo/sangre , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Embarazo , Adulto Joven
20.
Acta Neuropathol ; 135(2): 201-212, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29209767

RESUMEN

Abeta deposits and tau pathology were investigated in 24 French patients that died from iatrogenic Creutzfeldt-Jakob disease after exposure to cadaver-derived human growth hormone (c-hGH) in the 1980s. Abeta deposits were found only in one case that had experienced one of the longest incubation periods. Three cases had also intracellular tau accumulation. The analysis of 24 batches of c-hGH, produced between 1974 and 1988, demonstrated for the first time the presence of Abeta and tau contaminants in c-hGH (in 17 and 6 batches, respectively). The incubation of prion disease was shorter in the French patients than the incubation times reported in two previously published British series. We interpreted the low incidence of Abeta in this French series as a consequence of the shorter incubation period observed in France, as compared to that observed in the United Kingdom. This concept suggested that a mean incubation period for the development of detectable Abeta deposits would be longer than 18 years after the first exposure. Moreover, we hypothesized that tau pathology might also be transmissible in humans.


Asunto(s)
Encéfalo/patología , Síndrome de Creutzfeldt-Jakob/patología , Síndrome de Creutzfeldt-Jakob/transmisión , Contaminación de Medicamentos , Hormona de Crecimiento Humana , Adulto , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Cadáver , Estudios de Cohortes , Síndrome de Creutzfeldt-Jakob/metabolismo , Francia , Hormona de Crecimiento Humana/administración & dosificación , Humanos , Enfermedad Iatrogénica , Inmunoensayo , Periodo de Incubación de Enfermedades Infecciosas , Proteínas Priónicas/genética , Proteínas Priónicas/metabolismo , Adulto Joven , Proteínas tau/metabolismo
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