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1.
Reproduction ; 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38941180

RESUMEN

This study investigated the methylation patterns of H3K4me3 and H3K9me3, as well as the mRNA expression of genes encoding the epigenetic regulators KDM1AX1, KDM1AX2, and KDM3A in goat preantral follicles developed in vivo (Uncultured control) or after in vitro culture for 7 days in either the absence (α-MEM+) or presence of conditioned medium (α-MEM+ + CM) from Wharton's jelly mesenchymal stem cells (WJ-MSCs). In the in vivo setting, all follicular categories exhibited similar H3K4me3 and H3K9me3 patterns, and transcripts of KDM1AX1, KDM1AX2, and KDM3A were detected in all samples. During in vitro culture, α-MEM+ + CM enhanced several important aspects. It increased the percentage of normal growing follicles, oocyte diameters across all categories, stromal cell density, and the H3K4me3 methylation pattern in preantral follicles. Simultaneously, it decreased the levels of reduced thiols and reactive oxygen species in the spent media, diminished the presence of lipofuscin aggresomes, lowered granulosa cell apoptotic rates, and reduced the H3K9me3 methylation pattern in preantral follicles. In conclusion, the findings from this study provide compelling evidence that supplementing the in vitro culture medium (α-MEM+) with CM from WJ-MSCs has a protective effect on goat preantral follicles. Notably, CM supplementation preserved follicular survival, as evidenced by enhanced follicular and oocyte growth and increased stromal cell density when compared to the standard culture conditions in the α-MEM+ medium. Furthermore, CM reduced oxidative stress and apoptosis and promoted alterations in H3K4me3 and H3K9me3 patterns.

2.
Angiogenesis ; 26(3): 365-384, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36631598

RESUMEN

The Feline Leukemia Virus Subgroup C Receptor 1a (FLVCR1a) is a transmembrane heme exporter essential for embryonic vascular development. However, the exact role of FLVCR1a during blood vessel development remains largely undefined. Here, we show that FLVCR1a is highly expressed in angiogenic endothelial cells (ECs) compared to quiescent ECs. Consistently, ECs lacking FLVCR1a give rise to structurally and functionally abnormal vascular networks in multiple models of developmental and pathologic angiogenesis. Firstly, zebrafish embryos without FLVCR1a displayed defective intersegmental vessels formation. Furthermore, endothelial-specific Flvcr1a targeting in mice led to a reduced radial expansion of the retinal vasculature associated to decreased EC proliferation. Moreover, Flvcr1a null retinas showed defective vascular organization and loose attachment of pericytes. Finally, adult neo-angiogenesis is severely affected in murine models of tumor angiogenesis. Tumor blood vessels lacking Flvcr1a were disorganized and dysfunctional. Collectively, our results demonstrate the critical role of FLVCR1a as a regulator of developmental and pathological angiogenesis identifying FLVCR1a as a potential therapeutic target in human diseases characterized by aberrant neovascularization.


Asunto(s)
Células Endoteliales , Neoplasias , Adulto , Animales , Humanos , Ratones , Células Endoteliales/fisiología , Neovascularización Patológica/genética , Neovascularización Fisiológica/genética , Pez Cebra
3.
Nanotechnology ; 34(43)2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37473751

RESUMEN

Improving the thermal resilience of magnetic tunnel junctions (MTJs) broadens their applicability as sensing devices and is necessary to ensure their operation under harsh environments. In this work, we are address the impact of temperature on the degradation of the magnetic reference in field sensor stacks based on MgO-MTJs. Our study starts by simple MnIr/CoFe bilayers to gather enough insights into the role of critical morphological and magnetic parameters and their impact in the temperature dependent behavior. The exchange bias coupling field (Hex), coercive field (Hc), and blocking temperature (Tb) distribution are tuned, combining tailored growth conditions of the antiferromagnet and different buffer layer materials and stackings. This is achieved by a unique combination of ion beam deposition and magnetron sputtering, without vaccum break. Then, the work then extends beyond bilayers into more complex state-of-the-art MgO MTJ stacks as those employed in commercial sensing applications. We systematically address their characteristic fields, such as the width of the antiferromagnetic coupling plateau ΔH, and study their dependence on temperature. Although, [Ta/CuN] buffers showed higher key performance indications (e.g.Hex) at room temperature in both bilayers and MTJs, [Ta/Ru] buffers showed an overall wider ΔHup to 200 °C, more suitable to push high temperature operations. This result highlights the importance of properly design a suitable buffer layer system and addressing the complete MTJ behavior as function of temperature, to deliver the best stacking design with highest resilience to high temperature environments.

4.
HIV Med ; 22(6): 445-456, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33529485

RESUMEN

OBJECTIVES: We aimed to evaluate the accuracy of serological biomarkers for non-alcoholic fatty liver disease (NAFLD) and advanced fibrosis (METAVIR-F3F4) in HIV mono-infected individuals. METHODS: In all, 674 participants from the PROSPEC-HIV study (NCT02542020), who had blood sample tests and transient elastography (TE) performed on the same day, were eligible. Exclusion criteria were viral hepatitis co-infection (n = 90), abusive alcohol intake (n = 61), missing data (n = 47) or unreliable TE (n = 39). NAFLD was defined by controlled attenuation parameter ≥ 248 dB/m and advanced fibrosis by liver stiffness measurement ≥ 8.7 kPa with M probe or ≥ 7.2 kPa with XL probe. Biomarkers for NAFLD [Steato-ELSA, Fatty Liver Index (FLI), Hepatic Steatosis Index (HSI), NAFLD-Liver Fat Score (NAFLD-LFS)] and fibrosis [Fibrosis-4 score (FIB-4), Aspartate-to-Platelet Ratio Index (APRI) and NAFLD Fibrosis Score (NFS)] were calculated. RESULTS: A total of 437 patients [57% female, age = 44 (interquartile range: 35-52) years, body mass index (BMI) = 26.1 (23.4-29.3) kg/m2 , CD4 = 660 (427-901) cells/µL] were included. The prevalence [95% confidence interval (CI)] of NAFLD and advanced fibrosis were 38.2% (33.8-42.9) and 10.5% (8.0-13.8), respectively. The areas (95% CI) under the receiver operator curve (AUROCs) for diagnosis of NAFLD were 0.854 (0.818-0.889), 0.840 (0.804-0.877), 0.805 (0.762-0.847) and 0.793 (0.750-0.836) for Steato-ELSA, FLI, HSI and NAFLD-LFS (P < 0.001), respectively. All tests yielded satisfactory sensitivities, specificities and negative predictive values (NPVs). The AUROCs (95% CI) for diagnosis of advanced fibrosis were 0.736 (0.659-0.814), 0.700 (0.614-0.7851) and 0.795 (0.726-0.864) for FIB-4, APRI and NFS (P = 0.077), respectively. These tests yielded high specificities and negative predictive values (NPVs) > 90%. CONCLUSION: Biomarkers for NAFLD had a good accuracy and those for fibrosis had high specificities and NPVs. These tests should be integrated to HIV care to detect NAFLD and to exclude advanced liver fibrosis.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Infecciones por VIH , Enfermedad del Hígado Graso no Alcohólico , Adulto , Biomarcadores , Biopsia , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/patología , Humanos , Hígado/patología , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/epidemiología , Masculino , Enfermedad del Hígado Graso no Alcohólico/diagnóstico
5.
J Autoimmun ; 117: 102574, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33307312

RESUMEN

The T-cell receptor (TCR) is a highly polymorphic surface receptor that allows T-cells to recognize antigenic peptides presented on the major histocompatibility complex (MHC). Changes in the TCR repertoire have been observed in several autoimmune conditions, and these changes are suggested to predispose autoimmunity. Multiple lines of evidence have implied an important role for T-cells in the pathogenesis of Systemic Sclerosis (SSc), a complex autoimmune disease. One of the major questions regarding the roles of T-cells is whether expansion and activation of T-cells observed in the diseases pathogenesis is antigen driven. To investigate the temporal TCR repertoire dynamics in SSc, we performed high-throughput sequencing of CD4+ and CD8+ TCRß chains on longitudinal samples obtained from four SSc patients collected over a minimum of two years. Repertoire overlap analysis revealed that samples taken from the same individual over time shared a high number of TCRß sequences, indicating a clear temporal persistence of the TCRß repertoire in CD4+ as well as CD8+ T-cells. Moreover, the TCRßs that were found with a high frequency at one time point were also found with a high frequency at the other time points (even after almost four years), showing that frequencies of dominant TCRßs are largely consistent over time. We also show that TCRß generation probability and observed TCR frequency are not related in SSc samples, showing that clonal expansion and persistence of TCRßs is caused by antigenic selection rather than convergent recombination. Moreover, we demonstrate that TCRß diversity is lower in CD4+ and CD8+ T-cells from SSc patients compared with memory T-cells from healthy individuals, as SSc TCRß repertoires are largely dominated by clonally expanded persistent TCRß sequences. Lastly, using "Grouping of Lymphocyte Interactions by Paratope Hotspots" (GLIPH2), we identify clusters of TCRß sequences with homologous sequences that potentially recognize the same antigens and contain TCRßs that are persist in SSc patients. In conclusion, our results show that CD4+ and CD8+ T-cells are highly persistent in SSc patients over time, and this persistence is likely a result from antigenic selection. Moreover, persistent TCRs form high similarity clusters with other (non-)persistent sequences that potentially recognize the same epitopes. These data provide evidence for an antigen driven expansion of CD4+/CD8+ T-cells in SSc.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Receptores de Antígenos de Linfocitos T/genética , Esclerodermia Sistémica/etiología , Esclerodermia Sistémica/metabolismo , Adulto , Antígenos/inmunología , Susceptibilidad a Enfermedades , Epítopos , Femenino , Frecuencia de los Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Memoria Inmunológica , Inmunofenotipificación , Estudios Longitudinales , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Receptores de Antígenos de Linfocitos T/metabolismo , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Receptores de Antígenos de Linfocitos T alfa-beta/metabolismo , Esclerodermia Sistémica/patología
6.
Climacteric ; 24(3): 305-312, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33709858

RESUMEN

BACKGROUND: Menopausal transition is a physiological process encompassing hormonal and body changes that impact women's health and life quality. This period may be characterized by the Stages of Reproductive Aging Workshop (STRAW + 10) criteria using menstrual patterns. Use of the STRAW + 10 is uncertain in HIV infection. We aimed to characterize menopausal transition in women with HIV (WWH) using the STRAW + 10 criteria, hormonal measures and menopause symptoms. METHODS: We performed a cross-sectional study, nested to the HIV-Infected Women's Cohort, in Rio de Janeiro, Brazil. Eligible women included those aged 30 years or older, without clinical or surgical menopause, hormonal contraception, replacement therapy and ovarian disorders. We conducted face-to-face interviews and collected blood samples for follicle stimulating hormone (FSH) and estradiol measures. RESULTS: We enrolled 328 WWH (28.3% of women in the cohort). The distribution of age, hormonal levels and reported symptoms per each STRAW + 10 stage was consistent with the expected distribution in the menopausal transition. Age and FSH significantly increased and estradiol decreased from stage -2 (7 + days of menstrual delay) to stage +2 (8 + years of amenorrhea). CONCLUSIONS: The present results support use of the STRAW + 10 to characterize the menopausal transition of WWH with good clinical and immunological control.


Asunto(s)
Envejecimiento/fisiología , Infecciones por VIH/fisiopatología , VIH , Menopausia/fisiología , Adulto , Brasil , Estudios de Cohortes , Estudios Transversales , Estradiol/sangre , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Persona de Mediana Edad
7.
Med Oral Patol Oral Cir Bucal ; 26(3): e334-e340, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33340085

RESUMEN

BACKGROUND: Metallothioneins (MTs) gene polymorphisms have been associated with the ability of free radical scavenging and detoxification of heavy metals leading to cancer development. Our aim was to revisit, in a Brazilian population, single-nucleotide polymorphisms (SNPs) of the MT gene family previously associated with oral squamous cell carcinoma (OSCC). MATERIAL AND METHODS: A case-control investigation with 28 OSCC patients and 45 controls was conducted, using conventional risk factors (tobacco use and alcohol consumption) as covariates. SNPs genotyping for rs8052334 (MT1B), rs964372 (MT1B), and rs1610216 (MT2A) was performed by PCR-RFLP, and SNPs for rs11076161 (MT1A) were analyzed by TaqMan assay. RESULTS: The only SNP associated with increased risk for OSCC was the MT-1A AA genotype (OR = 4.7; p = 0.01). We have also evidenced for the first time a significant linkage disequilibrium between the SNPs of MT-2A and MT-1A in this population with the highest frequency (30%) of the unfavorable haplotype G/A/C/T (rs1610216 / rs11076161 / rs964372 / rs8052334) of MT gene polymorphisms (OR = 6.2; p = 0.04). Interestingly, after removing the effects of conventional risk factors, we have uncovered the significance of the AA genotype of the rs11076161 with increased odds of 19-fold higher towards OSCC development. CONCLUSIONS: This is the first demonstration that a significant linkage disequilibrium among gene polymorphisms of the MT family may affect susceptibility to oral cancer, which is conditioned by the G/A/C/T haplotype (rs1610216/rs11076161/rs964372/ rs8052334) and the MT-1A gene polymorphism has a potential clinical utility for the OSCC risk assessment.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Neoplasias de la Boca , Brasil , Carcinoma de Células Escamosas/genética , Estudios de Casos y Controles , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Metalotioneína/genética , Neoplasias de la Boca/genética , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Carcinoma de Células Escamosas de Cabeza y Cuello
8.
Nanotechnology ; 31(13): 135702, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-31801117

RESUMEN

Novel applications for memory devices demand nanoscale flexible structures. In particular, resistive switching (RS) devices are promising candidates for wearable and implantable technologies. Here, the Pt/Si/Ag/TiW metal-insulator-metal structure was fabricated and characterized on top of flexible substrates using a straightforward microfabrication process. We also showed that these substrates are compatible with sputtering deposition. RS was successfully achieved using both commercial cellulose cleanroom paper and bacterial cellulose, and polymer (PET) substrates. The bipolar switching behavior was observed for both flat and bent (under a radius of 3.5 mm) configurations. The observed phenomenon was explained by the formation/rupture of metallic Ag filaments in the otherwise insulating Si host layer.

9.
Med Oral Patol Oral Cir Bucal ; 25(5): e616-e625, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32683391

RESUMEN

BACKGROUND: The aim of this study was to describe the relative frequency and the main demographic and clinic-radiographic features related to patients diagnosed with Simple bone cyst (SBC) in an Oral Diagnosis Service in Southeast Brazil and present a review and discussion of international literature on this topic. MATERIAL AND METHODS: SBC cases from our service encompassing the period between 1978 and 2017 were selected. In addition, a literature search was performed in the Pubmed/MEDLINE online electronic database published between 1951 and 2019. RESULTS: A total of 2,459 cystic lesions were documented in our service, thus 60 patients were diagnosed with the SBC representing 2.4% of all jaw cystic. Most of cases were asymptomatic. Multiple SBC lesions were seen in two patients (3.4%) and association with cemento-osseous dysplasia was seen in one female patient (1.7%). A total of 793 cases were enrolled in this literature review. CONCLUSIONS: The SBC is an asymptomatic lesion often discovered in routine image exams in young patients. The unilocular, well defined margin with scalloped appearance is characteristic and helps the definition of diagnosis. This review suggests a different epidemiologic trend concerning to the sex and it confirms the posterior region of mandible as the more frequent location. The conservative treatment with limited exploration and curettage remains as the gold-standard treatment.


Asunto(s)
Quistes Óseos , Tumores Odontogénicos , Brasil , Femenino , Humanos , Mandíbula , Instituciones Académicas
10.
J Helminthol ; 92(5): 618-629, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28974282

RESUMEN

Pterygodermatites (Paucipectines) zygodontomis, a nematode parasite of the small intestine of the rodent Necromys lasiurus, from Uberlândia, Minas Gerais state, Brazil, was analysed by light and scanning electron microscopy. Additionally, phylogenies were inferred from the mitochondrially encoded cytochrome c oxidase I gene (MT-CO1). Details of the helminth surface, such as the oral aperture, cephalic papillae, papillae in the posterior region of the body and longitudinal cuticular elements represented by spine-like projections and fans are presented, adding new taxonomic details. Molecular phylogenetic analysis, based on the MT-CO1, demonstrated that P. (P.) zygodontomis and Pterygodermatites (Paucipectines) jaegerskioldi form a unique evolutionary unit in accordance with the subgenus Paucipectines and corroborated their occurrence in cricetid and didelphid hosts.


Asunto(s)
Enfermedades de los Roedores/parasitología , Sigmodontinae/parasitología , Infecciones por Spirurida/veterinaria , Spirurina/clasificación , Spirurina/aislamiento & purificación , Estructuras Animales/anatomía & histología , Animales , Brasil , Análisis por Conglomerados , Complejo IV de Transporte de Electrones/genética , Microscopía , Microscopía Electrónica , Filogenia , Análisis de Secuencia de ADN , Infecciones por Spirurida/parasitología , Spirurina/anatomía & histología , Spirurina/genética
11.
Med Oral Patol Oral Cir Bucal ; 23(3): e262-e268, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29680841

RESUMEN

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease mediated by T cells, which manifests as reticular (white) or erosive (red) lesions, that are eventually painful. Oral lichenoid lesion (OLL) are distinguished from OLP by the presence of precipitating factors. The aim of this study was to evaluate whether the presence of metallothionein, which is involved in anti-apoptotic pathways and the anti-oxidative response, could serve as a differential diagnostic for OLP and OLL. MATERIAL AND METHODS: We evaluated the expression of metallothionein in 40 cases of OLP and 20 cases of OLL using immunohistochemistry. RESULTS AND CONCLUSIONS: White OLP has higher concentrations of metallothionein than red OLP in basal and parabasal layers. Moreover, metallothionein was more frequently observed in the cytoplasm and nuclei of basal cells in OLP patients compared to the same regions of OLL cases. Metallothionein levels are related to OLP severity and may contribute to a differential diagnosis between OLP and OLL.


Asunto(s)
Amalgama Dental , Liquen Plano Oral/diagnóstico , Liquen Plano Oral/metabolismo , Metalotioneína/biosíntesis , Adulto , Amalgama Dental/efectos adversos , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/diagnóstico , Enfermedades de la Boca/etiología , Enfermedades de la Boca/patología
12.
Electrophoresis ; 38(6): 869-875, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27990652

RESUMEN

The Basque Country is home to the Latxa sheep breed, which is divided in several varieties such as Latxa Black Face (LBKF) and Latxa Blonde Face (LBLF). Mitochondrial DNA control region analysis of 174 male sheep (97 LBKF and 77 LBLF) was performed with the objective of characterizing the maternal lineages of these two varieties that are the basis to produce the cheese with Idiazabal quality label. The percentage of unique haplotypes was 77.32% in LBKF and 67.53% in LBLF. Most of the individuals were classified into B haplogroup (98.85%), while A haplogroup was much less frequent. Two Latxa individuals (one LBKF and one LBLF), both belonging to B haplogroup, displayed an additional 75/76 bp tandem repeat motif. Only 33 other sequences with this repeat motif were found among 11 061 sheep sequences included in the GenBank database. Gene expression was analyzed in peripheral blood leukocytes since the additional 75/76 bp repeat motif falls within ETAS1, a domain with a possible function in regulation of replication and transcription. The mRNA expression from four mitochondrial genes (COI, cyt b, ND1, and ND2) was analyzed in the two individuals of this study with a fifth repeat motif and in four without it. Although lower transcription was observed when the additional 75/76 bp repeat motif was present, no statistically significant differences were observed. Therefore, the variation in the number of the 75/76 repeat motif does not seem to modify the gene expression rate in mitochondrial genes.


Asunto(s)
ADN Mitocondrial/sangre , Ovinos/genética , Animales , Secuencia de Bases , ADN Mitocondrial/genética , Regulación de la Expresión Génica , Genes Mitocondriales , Variación Genética , Haplotipos , Masculino , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/sangre , España , Secuencias Repetidas en Tándem
13.
J Nanosci Nanotechnol ; 17(1): 564-67, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29630146

RESUMEN

The recent realization of memristors, nanodevices exhibiting non-volatile resistive switching, has sparked tremendous interest for applications in fields such as nonvolatile memories. Here we report unipolar resistive switching in Pt/MgO/Ta/Ru structures, with an oxide barrier thickness of only 15 nm. No electroforming process was required to achieve resistive switching and an ohmic conduction mechanism is associated with the ON state. We observed an inverse dependence of the ON state resistance on the SET current compliance and average values of 1.61 V and 1.38 V for the SET and RESET voltages, respectively. We show the stability of the switching for over 40 cycles and a clear separation of the ON (10¹ Ω) and OFF (10² Ω) states during at least 104 s.

14.
AAPS PharmSciTech ; 18(5): 1785-1794, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27800567

RESUMEN

In the absence of an official dissolution method for modified-release tablets of gliclazide, dissolution parameters, such as apparatuses (1, 2, and 3), rotation speeds, pH, and composition of the dissolution medium were investigated. The results show that although the drug presents a pH-mediated solubility (pH 7.0 > 6.8 > 6.4 > 6.0 > 5.5 > 4.5), the in vitro release of the studied tablets was not dependent on this parameter, despite of the apparatus tested. On the other hand, the rotation speed demonstrated a greater influence (100 rpm >50 rpm). Using similar hydrodynamic conditions, the three different apparatuses were compared in pH 6.8 and provided the following trend: apparatus 1 at 100 rpm >2 at 50 rpm ≈3 at 10 dpm. As a complete, but slow release is expected from modified-release formulations, apparatus 2, in phosphate buffer pH 6.8 and 100 rpm, were selected as the optimized dissolution method. In comparison to apparatus 1 under the same conditions, the paddle avoids the stickiness of formulation excipients at the mesh of the basket, which could prejudice the release of gliclazide. Results obtained with biorelevant medium through the developed dissolution method were similar to the buffer solution pH 6.8. The application of the optimized method as a quality control test between two different brands of gliclazide modified-release tablets showed that both dissolution profiles were considered similar by the similarity factor (f2 = 51.8). The investigation of these dissolution profiles indicated a dissolution kinetic following first-order model.


Asunto(s)
Química Farmacéutica/métodos , Gliclazida/análisis , Gliclazida/química , Preparaciones de Acción Retardada/análisis , Preparaciones de Acción Retardada/química , Excipientes/análisis , Excipientes/química , Solubilidad , Comprimidos/química
15.
Biochim Biophys Acta ; 1842(1): 7-21, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24120997

RESUMEN

In Parkinson's disease mitochondrial dysfunction can lead to a deficient ATP supply to microtubule protein motors leading to mitochondrial axonal transport disruption. Compromised axonal transport will then lead to a disorganized distribution of mitochondria and other organelles in the cell, as well as, the accumulation of aggregated proteins like alpha-synuclein. Moreover, axonal transport disruption can trigger synaptic accumulation of autophagosomes packed with damaged mitochondria and protein aggregates promoting synaptic failure. We previously observed that neuronal-like cells with an inherent mitochondrial impairment derived from PD patients contain a disorganized microtubule network, as well as, alpha-synuclein oligomer accumulation. In this work we provide new evidence that an agent that promotes microtubule network assembly, NAP (davunetide), improves microtubule-dependent traffic, restores the autophagic flux and potentiates autophagosome-lysosome fusion leading to autophagic vacuole clearance in Parkinson's disease cells. Moreover, NAP is capable of efficiently reducing alpha-synuclein oligomer content and its sequestration by the mitochondria. Most interestingly, NAP decreases mitochondrial ubiquitination levels, as well as, increases mitochondrial membrane potential indicating a rescue in mitochondrial function. Overall, we demonstrate that by improving microtubule-mediated traffic, we can avoid mitochondrial-induced damage and thus recover cell homeostasis. These results prove that NAP may be a promising therapeutic lead candidate for neurodegenerative diseases that involve axonal transport failure and mitochondrial impairment as hallmarks, like Parkinson's disease and related disorders.


Asunto(s)
Microtúbulos/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Enfermedades Mitocondriales/metabolismo , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Oligopéptidos/farmacología , Enfermedad de Parkinson/metabolismo , Anciano , Autofagia/efectos de los fármacos , Estudios de Casos y Controles , Línea Celular , Femenino , Humanos , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Microtúbulos/metabolismo , Microtúbulos/ultraestructura , Persona de Mediana Edad , Mitocondrias/metabolismo , Enfermedades Mitocondriales/patología , Neuronas/metabolismo , Neuronas/patología , Enfermedad de Parkinson/patología , Ubiquitinación/efectos de los fármacos , Vacuolas/efectos de los fármacos , Vacuolas/metabolismo , alfa-Sinucleína/metabolismo
16.
Biochim Biophys Acta ; 1842(7): 1154-66, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24747740

RESUMEN

The main purpose of this study was to examine whether streptozotocin (STZ)-induced type 1 diabetes (T1D) and insulin (INS) treatment affect mitochondrial function, fission/fusion and biogenesis, autophagy and tau protein phosphorylation in cerebral cortex from diabetic rats treated or not with INS. No significant alterations were observed in mitochondrial function as well as pyruvate levels, despite the significant increase in glucose levels observed in INS-treated diabetic rats. A significant increase in DRP1 protein phosphorylated at Ser616 residue was observed in the brain cortex of STZ rats. Also an increase in NRF2 protein levels and in the number of copies of mtDNA were observed in STZ diabetic rats, these alterations being normalized by INS. A slight decrease in LC3-II levels was observed in INS-treated rats when compared to STZ diabetic animals. An increase in tau protein phosphorylation at Ser396 residue was observed in STZ diabetic rats while INS treatment partially reversed that effect. Accordingly, a modest reduction in the activation of GSK3ß and a significant increase in the activity of phosphatase 2A were found in INS-treated rats when compared to STZ diabetic animals. No significant alterations were observed in caspases 9 and 3 activity and synaptophysin and PSD95 levels. Altogether our results show that mitochondrial alterations induced by T1D seem to involve compensation mechanisms since no significant changes in mitochondrial function and synaptic integrity were observed in diabetic animals. In addition, INS treatment is able to normalize the alterations induced by T1D supporting the importance of INS signaling in the brain.


Asunto(s)
Autofagia/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Insulina/farmacología , Mitocondrias/metabolismo , Proteínas tau/metabolismo , Animales , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Corteza Cerebral/metabolismo , Diabetes Mellitus Experimental/inducido químicamente , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/inducido químicamente , Diabetes Mellitus Tipo 1/metabolismo , Dinaminas/metabolismo , Glucosa/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Fosforilación/efectos de los fármacos , Ácido Pirúvico/metabolismo , Ratas , Ratas Wistar
17.
Biochim Biophys Acta ; 1842(9): 1444-53, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24832819

RESUMEN

The endoplasmic reticulum (ER) is the principal organelle responsible for the proper folding/processing of nascent proteins and perturbed ER function leads to a state known as ER stress. Mammalian cells try to overcome ER stress through a set of protein signaling pathways and transcription factors termed the unfolded protein response (UPR). However, under unresolvable ER stress conditions, the UPR is hyperactivated inducing cell dysfunction and death. The accumulation of misfolded proteins in the brain of Alzheimer's disease (AD) patients suggests that alterations in ER homeostasis might be implicated in the neurodegenerative events that characterize this disorder. This review discusses the involvement of ER stress in the pathogenesis of AD, focusing the processing and trafficking of the AD-related amyloid precursor protein (APP) during disease development. The potential role of ER as a therapeutic target in AD will also be debated.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Precursor de Proteína beta-Amiloide/metabolismo , Retículo Endoplásmico/metabolismo , Animales , Humanos , Transporte de Proteínas
18.
Biochim Biophys Acta ; 1832(4): 527-41, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23314196

RESUMEN

According to World Health Organization estimates, type 2 diabetes (T2D) is an epidemic (particularly in under development countries) and a socio-economic challenge. This is even more relevant since increasing evidence points T2D as a risk factor for Alzheimer's disease (AD), supporting the hypothesis that AD is a "type 3 diabetes" or "brain insulin resistant state". Despite the limited knowledge on the molecular mechanisms and the etiological complexity of both pathologies, evidence suggests that neurodegeneration/death underlying cognitive dysfunction (and ultimately dementia) upon long-term T2D may arise from a complex interplay between T2D and brain aging. Additionally, decreased brain insulin levels/signaling and glucose metabolism in both pathologies further suggests that an effective treatment strategy for one disorder may be also beneficial in the other. In this regard, one such promising strategy is a novel successful anti-T2D class of drugs, the glucagon-like peptide-1 (GLP-1) mimetics (e.g. exendin-4 or liraglutide), whose potential neuroprotective effects have been increasingly shown in the last years. In fact, several studies showed that, besides improving peripheral (and probably brain) insulin signaling, GLP-1 analogs minimize cell loss and possibly rescue cognitive decline in models of AD, Parkinson's (PD) or Huntington's disease. Interestingly, exendin-4 is undergoing clinical trials to test its potential as an anti-PD therapy. Herewith, we aim to integrate the available data on the metabolic and neuroprotective effects of GLP-1 mimetics in the central nervous system (CNS) with the complex crosstalk between T2D-AD, as well as their potential therapeutic value against T2D-associated cognitive dysfunction.


Asunto(s)
Enfermedad de Alzheimer , Biomimética , Diabetes Mellitus Tipo 2 , Péptido 1 Similar al Glucagón , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Encéfalo/metabolismo , Encéfalo/fisiopatología , Sistema Nervioso Central/efectos de los fármacos , Sistema Nervioso Central/fisiopatología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Exenatida , Péptido 1 Similar al Glucagón/análogos & derivados , Péptido 1 Similar al Glucagón/genética , Péptido 1 Similar al Glucagón/metabolismo , Péptido 1 Similar al Glucagón/uso terapéutico , Glucosa/metabolismo , Humanos , Resistencia a la Insulina/genética , Liraglutida , Péptidos/uso terapéutico , Ponzoñas/uso terapéutico
19.
Mol Cell Biochem ; 394(1-2): 13-22, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24833464

RESUMEN

Mitochondria have a crucial role in the supply of energy to the brain. Mitochondrial alterations can lead to detrimental consequences on the function of brain cells and are thought to have a pivotal role in the pathogenesis of several neurologic disorders. This study was aimed to evaluate mitochondrial function, fusion-fission and biogenesis and autophagy in brain cortex of 6-month-old Goto-Kakizaki (GK) rats, an animal model of nonobese type 2 diabetes (T2D). No statistically significant alterations were observed in mitochondrial respiratory chain and oxidative phosphorylation system. A significant decrease in the protein levels of OPA1, a protein that facilitates mitochondrial fusion, was observed in brain cortex of GK rats. Furthermore, a significant decrease in the protein levels of LC3-II and a significant increase in protein levels of mTOR phosphorylated at serine residue 2448 were observed in GK rats suggesting a suppression of autophagy in diabetic brain cortex. No significant alterations were observed in the parameters related to mitochondrial biogenesis. Altogether, these results demonstrate that during the early stages of T2D, brain mitochondrial function is maintained in part due to a delicate balance between mitochondrial fusion-fission and biogenesis and autophagy. However, future studies are warranted to evaluate the role of mitochondrial quality control pathways in late stages of T2D.


Asunto(s)
Corteza Cerebral/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Metabolismo Energético , Mitocondrias/metabolismo , Recambio Mitocondrial , Animales , Autofagia , Corteza Cerebral/patología , Diabetes Mellitus Tipo 2/patología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , GTP Fosfohidrolasas/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Mitocondrias/patología , Dinámicas Mitocondriales , Fosforilación , Ratas , Ratas Wistar , Serina-Treonina Quinasas TOR/metabolismo , Factores de Tiempo
20.
Vox Sang ; 105(1): 65-72, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23398146

RESUMEN

BACKGROUND AND OBJECTIVES: A number of DNA-based methods to genotype the alleles coding for HNA have been described, but all require the separate amplification and analysis of each allele. The aim was to develop a DNA-based method for simultaneous detection of HNA-1, HNA-3, HNA-4 and HNA-5 alleles. MATERIALS AND METHODS: An allele-specific primer extension method was used in combination with magnetic beads from Luminex technology. PCR-sequence-specific primers (SSP) was used to resolve the presence of the HNA-1b allele in samples assigned by the Luminex bead assay as HNA-1a/-1b/-1c or HNA-1b/-1c. HNA allele frequencies were determined in a panel of 140 randomly selected English Caucasoid blood donors. RESULTS: HNA allelic types were compared with historical results, and 100% concordance was found. Only eight of the 97 samples used in the validation required additional testing by PCR-SSP. Allele frequencies were determined in the blood donor population as follows: 0·318 for HNA-1a, 0·668 for HNA-1b, 0·014 for HNA-1c, 0·768 for HNA-3a, 0·232 for HNA-3b, 0·882 for HNA-4a, 0·118 for HNA-4b, 0·736 for HNA-5a and 0·264 for HNA-5b. CONCLUSION: A multiplex Luminex bead assay for the simultaneous detection of HNA-1, HNA-3, HNA-4 and HNA-5 alleles is described that enables rapid typing of donors to support HNA alloimmunized patients who require HNA-compatible blood products.


Asunto(s)
Donantes de Sangre , Frecuencia de los Genes , Isoantígenos/genética , Neutrófilos , Análisis de Secuencia de ADN , Población Blanca/genética , Alelos , Inglaterra , Femenino , Genotipo , Humanos , Masculino
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