Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Micromachines (Basel) ; 14(9)2023 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-37763847

RESUMEN

A high-sensitivity plasmonic photonic crystal fiber (PCF) sensor is designed and a metal thin film is embedded for achieving surface plasmon resonance (SPR), which can detect the magnetic field and temperature simultaneously. Within the plasmonic PCF sensor, the SPR sensing is accomplished by coating both the upper sensing channel (Ch1) and the lower sensing channel (Ch2) with gold film. In addition, the temperature-sensitive medium polydimethylsiloxane (PDMS) is chosen to fill in Ch1, allowing the sensor to respond to the temperature. The magnetic field-sensitive medium magnetic fluid (MF) is chosen to fill in Ch2, allowing this sensor to respond to the magnetic field. During these processes, this proposed SPR-PCF sensor can achieve dual-parameter sensing. The paper also investigates the electrical field characteristics, structural parameters and sensing performance using COMSOL. Finally, under the magnetic field range of 50-130 Oe, this sensor has magnetic field sensing sensitivities of 0 pm/Oe (Ch1) and 235 pm/Oe (Ch2). In addition, this paper also investigates the response of temperature. Under the temperature range of 20-40 °C, Ch1 and Ch2 have temperature sensitivities of -2000 pm/°C and 0 pm/°C, respectively. It is noteworthy that the two sensing channels respond to only a single physical parameter; this sensing performance is not common in dual-parameter sensing. Due to this sensing performance, it can be found that the magnetic field and temperature can be detected by this designed SPR-PCF sensor simultaneously without founding and calculating a sensing matrix. This sensing performance can solve the cross-sensitivity problem of magnetic field and temperature, thus reducing the measurement error. Since it can sense without a matrix, it further can solve the ill-conditioned matrix and nonlinear change in sensitivity problems in dual-parameter sensing. These excellent sensing capabilities are very important for carrying out multiparameter sensing in complicated environments.

2.
Quant Imaging Med Surg ; 13(5): 3365-3370, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37179903
3.
BMC Neurosci ; 23(1): 3, 2022 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-34983390

RESUMEN

BACKGROUND: Parkinson's disease (PD) and dementia with Lewy bodies (DLB) are common age-related neurodegenerative diseases comprising Lewy body spectrum disorders associated with cortical and subcortical Lewy body pathology. Over 30% of PD patients develop PD dementia (PDD), which describes dementia arising in the context of established idiopathic PD. Furthermore, Lewy bodies frequently accompany the amyloid plaque and neurofibrillary tangle pathology of Alzheimer's disease (AD), where they are observed in the amygdala of approximately 60% of sporadic and familial AD. While PDD and DLB share similar pathological substrates, they differ in the temporal onset of motor and cognitive symptoms; however, protein markers to distinguish them are still lacking. METHODS: Here, we systematically studied a series of AD and PD pathogenesis markers, as well as mitochondria, mitophagy, and neuroinflammation-related indicators, in the substantia nigra (SN), temporal cortex (TC), and caudate and putamen (CP) regions of human post-mortem brain samples from individuals with PDD and DLB and condition-matched controls. RESULTS: We found that p-APPT668 (TC), α-synuclein (CP), and LC3II (CP) are all increased while the tyrosine hydroxylase (TH) (CP) is decreased in both PDD and DLB compared to control. Also, the levels of Aß42 and DD2R, IBA1, and p-LRRK2S935 are all elevated in PDD compared to control. Interestingly, protein levels of p-TauS199/202 in CP and DD2R, DRP1, and VPS35 in TC are all increased in PDD compared to DLB. CONCLUSIONS: Together, our comprehensive and systematic study identified a set of signature proteins that will help to understand the pathology and etiology of PDD and DLB at the molecular level.


Asunto(s)
Enfermedad de Alzheimer , Demencia , Enfermedad por Cuerpos de Lewy , Enfermedad de Parkinson , Enfermedad de Alzheimer/complicaciones , Encéfalo/patología , Demencia/complicaciones , Demencia/patología , Humanos , Enfermedad por Cuerpos de Lewy/complicaciones , Enfermedad por Cuerpos de Lewy/patología , Enfermedad de Parkinson/complicaciones
4.
Biomaterials ; 271: 120747, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33740615

RESUMEN

Transplantation of differentiated neurons derived from either human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs) is an emerging therapeutic strategy for various neurodegenerative diseases. One important aspect of transplantation is the accessibility to track and control the activity of the stem cells-derived neurons post-transplantation. Recently, the characteristics of organic nanoparticles (NPs) with aggregation-induced emission (AIE) have emerged as efficient cell labeling reagents, where positive outcomes were observed in long-term cancer cell tracing in vivo. In the current study, we designed, synthesized, and analyzed the biocompatibility of AIE-NPs in cultured neurons such as in mouse neuronal progenitor cells (NPCs) and hESC-derived neurons. Our data demonstrated that AIE-NPs show high degree of penetration into cells and presented intracellular long-term retention in vitro without altering the neuronal proliferation, differentiation, and viability. Furthermore, we have tracked AIE-NPs labeled neuronal grafts in mouse brain striatum in various time points post-transplantation. We demonstrated prolonged cellular retention of AIE-NPs labeled neuronal grafts 1 month post-transplantation in mouse brain striatum. Lastly, we have shown activation of brain microglia in response to AIE-NPs labeled grafts. Together, these findings highlight the potential application of AIE-NPs in neuronal transplantation.


Asunto(s)
Células Madre Embrionarias Humanas , Células Madre Pluripotentes Inducidas , Nanopartículas , Diferenciación Celular , Neuronas , Trasplante de Células Madre
5.
Front Neurosci ; 14: 558532, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33177975

RESUMEN

Curative therapies or treatments reversing the progression of Parkinson's disease (PD) have attracted considerable interest in the last few decades. PD is characterized by the gradual loss of dopaminergic (DA) neurons and decreased striatal dopamine levels. Current challenges include optimizing neuroprotective strategies, developing personalized drug therapy, and minimizing side effects from the long-term prescription of pharmacological drugs used to relieve short-term motor symptoms. Transplantation of DA cells into PD patients' brains to replace degenerated DA has the potential to change the treatment paradigm. Herein, we provide updates on current progress in stem cell-derived DA neuron transplantation as a therapeutic alternative for PD. We briefly highlight cell sources for transplantation and focus on cell assessment methods such as identification of genetic markers, single-cell sequencing, and imaging modalities used to access cell survival and function. More importantly, we summarize clinical reports of patients who have undergone cell-derived transplantation in PD to better perceive lessons that can be drawn from past and present clinical outcomes. Modifying factors include (1) source of the stem cells, (2) quality of the stem cells, (3) age of the patient, (4) stage of disease progression at the time of cell therapy, (5) surgical technique/practices, and (6) the use of immunosuppression. We await the outcomes of joint efforts in clinical trials around the world such as NYSTEM and CiRA to further guide us in the selection of the most suitable parameters for cell-based neurotransplantation in PD.

6.
Artículo en Inglés | MEDLINE | ID: mdl-33082835

RESUMEN

The continuing use of nonsteroidal anti-inflammatory drugs (NSAIDs) usually increases the side effects such as peptic ulcer and acute gastric lesions in the gastrointestinal tract. Cuttlebone (CB), isolated from Sepiella maindroni de Rochebrune, was reported to have antioxidant activities, but its role in the treatment of indomethacin-induced gastric lesions has not yet been confirmed. In this research, we investigate the protective effect of cuttlebone on indomethacin-related ulcers in rats and possible mechanisms. Here, gastric ulcers were induced by oral administration of indomethacin, and then the rats were treated with omeprazole (4 mg/kg) or different doses (750, 1500, and 3000 mg/kg of body weight) of cuttlebone. We evaluated lesion index, inflammation score, and a series of oxidant/antioxidant parameters. The data demonstrated that cuttlebone could protect against gastric ulcers induced by indomethacin in a dose-dependent manner (positive correlation). Also, these effects were associated with attenuating the expression of malonaldehyde (MDA) and increasing the levels of some protective ingredients like epidermal growth factor (EGF), prostaglandin E2 (PGE2), and superoxide dismutase (SOD). Thus, considering its ability to protect indomethacin-induced acute gastric mucosal lesions and the underlying mechanisms, CB might be a potential candidate for treating gastric damage caused by NSAIDs.

7.
Biomater Sci ; 8(17): 4861-4874, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-32789337

RESUMEN

Increasing evidence indicates superiority of three-dimensional (3D) in vitro cell culture systems over conventional two-dimensional (2D) monolayer cultures in mimicking native in vivo microenvironments. Tissue-engineered 3D culture models combined with stem cell technologies have advanced Alzheimer's disease (AD) pathogenesis studies. However, existing 3D neuronal models of AD overexpress mutant genes or have heterogeneities in composition, biological properties and cell differentiation stages. Here, we encapsulate patient induced pluripotent stem cell (iPSC) derived neural progenitor cells (NPC) in poly(lactic-co-glycolic acid) (PLGA) microtopographic scaffolds fabricated via wet electrospinning to develop a novel 3D culture model of AD. First, we enhanced cellular infiltration and distribution inside the scaffold by optimizing various process parameters such as fiber diameter, pore size, porosity and hydrophilicity. Next, we compared key neural stem cell features including viability, proliferation and differentiation in 3D culture with 2D monolayer controls. The 3D microfibrous substrate reduces cell proliferation and significantly accelerates neuronal differentiation within seven days of culture. Furthermore, 3D culture spontaneously enhanced pathogenic amyloid-beta 42 (Aß42) and phospho-tau levels in differentiated neurons carrying familial AD (FAD) mutations, compared with age-matched healthy controls. Overall, our tunable scaffold-based 3D neuronal culture platform serves as a suitable in vitro model that robustly recapitulates and accelerates the pathogenic characteristics of FAD-iPSC derived neurons.


Asunto(s)
Enfermedad de Alzheimer , Células Madre Pluripotentes Inducidas , Células-Madre Neurales , Diferenciación Celular , Humanos , Neuronas , Andamios del Tejido
8.
Stem Cell Res Ther ; 11(1): 347, 2020 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-32771055

RESUMEN

BACKGROUND: Significant developments in stem cell therapy for Parkinson's disease (PD) have already been achieved; however, methods for reliable assessment of dopamine neuron maturation in vivo are lacking. Establishing the efficacy of new cellular therapies using non-invasive methodologies will be critical for future regulatory approval and application. The current study examines the utility of neuroimaging to characterise the in vivo maturation, innervation and functional dopamine release of transplanted human embryonic stem cell-derived midbrain dopaminergic neurons (hESC-mDAs) in a preclinical model of PD. METHODS: Female NIH RNu rats received a unilateral stereotaxic injection of 6-OHDA into the left medial forebrain bundle to create the PD lesion. hESC-mDA cell and sham transplantations were carried out 1 month post-lesion, with treated animals receiving approximately 4 × 105 cells per transplantation. Behavioural analysis, [18F]FBCTT and [18F]fallypride microPET/CT, was conducted at 1, 3 and 6 months post-transplantation and compared with histological characterisation at 6 months. RESULTS: PET imaging revealed transplant survival and maturation into functional dopaminergic neurons. [18F]FBCTT-PET/CT dopamine transporter (DAT) imaging demonstrated pre-synaptic restoration and [18F]fallypride-PET/CT indicated functional dopamine release, whilst amphetamine-induced rotation showed significant behavioural recovery. Moreover, histology revealed that the grafted cells matured differently in vivo producing high- and low-tyrosine hydroxylase (TH) expressing cohorts, and only [18F]FBCTT uptake was well correlated with differentiation. CONCLUSIONS: This study provides further evidence for the value of in vivo functional imaging for the assessment of cell therapies and highlights the utility of DAT imaging for the determination of early post-transplant cell maturation and differentiation of hESC-mDAs.


Asunto(s)
Neuronas Dopaminérgicas , Enfermedad de Parkinson , Tomografía Computarizada por Tomografía de Emisión de Positrones , Animales , Modelos Animales de Enfermedad , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Femenino , Neuroimagen , Oxidopamina , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/terapia , Ratas
9.
ACS Appl Mater Interfaces ; 11(33): 29934-29940, 2019 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-31329412

RESUMEN

Constructing advanced anode materials with suitable operational potential and high energy density toward metal ion batteries is of significance for next-generation batteries. Carbon-coated porous Sb2Te3 nanoplates with high density and suitable operational potential, prepared by a hydrothermal and carbonization technique, manifest good electrochemical performance, including excellent rate capability, high capacities, and outstanding cycling performance. This performance can be traced to its special structure, including porous Sb2Te3 and the shell of carbon, which can provide fast charge transfer paths and maintain the structural stability for the entire material. The proposed strategy here of embedding porous high-density anode material in two-dimensional carbon provides a new avenue for designing anode materials with excellent gravimetric and volumetric capacities toward superior energy storage.

10.
Sci Rep ; 9(1): 7298, 2019 05 13.
Artículo en Inglés | MEDLINE | ID: mdl-31086212

RESUMEN

The World Health Organization has declared ZIKA virus (ZIKV) a global public health emergency, prompted by the association of ZIKV infections with severe brain abnormalities in the human fetus. ZIKV preferentially targets human neuronal precursor cells (NPCs) in both monolayer and cortical brain organoid culture systems and stunts their growth. Although ZIKV is well recognized to cause microcephaly, there is no systematic analysis to demonstrate the effect of ZIKV on central nervous system (CNS) development, including brain malformations and spinal cord dysfunction. Here, we conducted a longitudinal analysis to show that a novel mouse model (infected in utero and monitored after birth until adulthood) recapitulates the effects of ZIKV infection affecting neural stem cells fate and leads to a thinner cortex and a smaller brain. Furthermore, we demonstrate the effect of ZIKV on spinal cord function. Specifically, we found significant reductions in neuron numbers in the anterior horn of grey matter of the spinal cord and muscle dystrophy with a significant decrease in forepaw grip strength in the ZIKV group. Thus, the established mouse model of ZIKV infection leading to abnormal CNS development will help to further advance our understanding of the disease pathogenesis.


Asunto(s)
Microcefalia/virología , Distrofia Muscular Animal/virología , Efectos Tardíos de la Exposición Prenatal/virología , Infección por el Virus Zika/complicaciones , Virus Zika/patogenicidad , Animales , Encéfalo/citología , Encéfalo/embriología , Encéfalo/virología , Recuento de Células , Modelos Animales de Enfermedad , Extremidades/fisiopatología , Femenino , Humanos , Ratones , Microcefalia/patología , Fuerza Muscular/fisiología , Distrofia Muscular Animal/patología , Distrofia Muscular Animal/fisiopatología , Células-Madre Neurales/patología , Células-Madre Neurales/virología , Neuronas/patología , Neuronas/virología , Embarazo , Efectos Tardíos de la Exposición Prenatal/patología , Asta Ventral de la Médula Espinal/citología , Asta Ventral de la Médula Espinal/embriología , Asta Ventral de la Médula Espinal/virología , Virus Zika/aislamiento & purificación , Infección por el Virus Zika/virología
11.
Int J Endocrinol ; 2018: 1067603, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30310390

RESUMEN

OBJECTIVES: To compare the predictive ability of six anthropometric indices for identification of metabolic syndrome (MetS) and to determine their optimal cut-off points among Chinese adults. METHODS: A total of 59,029 participants were enrolled. Body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), a body shape index (ABSI), body roundness index (BRI), and conicity index (CI) were measured. Receiver-operating characteristic curves analyses were performed to determine the discriminatory power of these indices for the identification of cardiometabolic risks and diagnosis of MetS. The differences in the area under the curve (AUC) values among the indices were evaluated. The Youden index was used to determine the optimal cut-off points. RESULTS: WHtR and BRI exhibited the highest AUC values for identifying MetS and most cardiometabolic risk factors in both sexes, whereas ABSI showed the lowest AUC value. The general optimal cut-off points in women were 23.03 kg/m2 for BMI, 77.25 cm for WC, 0.490 for WHtR, and 3.179 for BRI; those in men were 24.64 kg/m2 for BMI, 87.25 cm for WC, 0.510 for WHtR, and 3.547 for BRI. The AUC values and cut-off points of the indices were also analyzed in each age and BMI category. CONCLUSIONS: In Chinese adults, WHtR and BRI showed a superior predictive power for MetS in both sexes, which can be used as simple and effective screening tools for cardiometabolic risks and MetS in clinical practice.

12.
J Tissue Eng Regen Med ; 12(9): 1944-1958, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30011422

RESUMEN

Alzheimer's disease (AD) is the most common form of dementia and is characterized by progressive memory loss, impairment of other cognitive functions, and inability to perform activities of daily life. The key to understanding AD aetiology lies in the development of effective disease models, which should ideally recapitulate all aspects pertaining to the disease. A plethora of techniques including in vivo, in vitro, and in silico platforms have been utilized in developing disease models of AD over the years. Each of these approaches has revealed certain essential characteristics of AD; however, none have managed to fully mimic the pathological hallmarks observed in the AD human brain. In this review, we will provide details into the genesis, evolution, and significance of the principal methods currently employed in modelling AD, the advantages and limitations faced in their application, including the headways made by each approach. This review will focus primarily on two-dimensional and three-dimensional in vitro modelling of AD, which during the last few years has made significant breakthroughs in the areas of AD pathology and therapeutic screening. In addition, a glimpse into state-of-the-art neural tissue engineering techniques incorporating biomaterials and microfluidics technologies is provided, which could pave the way for the development of more accurate and comprehensive AD models in the future.


Asunto(s)
Enfermedad de Alzheimer/patología , Técnicas de Cultivo de Célula/métodos , Modelos Biológicos , Animales , Modelos Animales de Enfermedad , Humanos , Células Madre Pluripotentes Inducidas/patología
13.
Atherosclerosis ; 263: 263-271, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28704699

RESUMEN

BACKGROUND AND AIMS: The association between anthropometric indices of body composition and arterial stiffness is inconclusive. The objective of this study was to examine the predictive ability of two new obesity indices: a body shape index (ABSI), and a body roundness index (BRI), for the identification of arterial stiffness among Chinese adults, as well as to compare the relative strength of association between the anthropometric indices and arterial stiffness. METHODS: A total of 10,197 subjects were recruited in this cross-sectional study. We tested the association between anthropometric indices (body mass index [BMI], waist circumference [WC], waist-height-ratio [WHtR], ABSI and BRI) and brachial-ankle pulse wave velocity (PWV). Receiver operating characteristic curve and area under curve (AUC) were employed to evaluate the predictive value of the anthropometric indices for identification of arterial stiffness. RESULTS: After adjusting for confounding variables, BRI (linear regression: 0.112; AUC: 0.726; OR: 1.228 for female and linear regression: 0.047; AUC: 0.631; OR: 1.173 for male) exhibited a more powerful predictive ability of arterial stiffness than ABSI (linear regression: 0.110; AUC: 0.674; OR: 1.315 for female and linear regression: 0.058; AUC: 0.610; OR: 1.150 for male) and WC (linear regression: 0.078; AUC: 0.699; logistic regression: negative for female and linear regression: negative; AUC: 0.593; logistic regression: negative for male) while having a similar predictive value to that of WHtR (linear regression: 0.113; AUC: 0.726; OR: 1.228 for female and linear regression: 0.047; AUC: 0.631; OR: 1.185 for male) among both sexes. BMI (linear and logistic regression: negative; AUC: 0.660 for female and 0.568 for male) had the lowest predictive power in both sex categories. The optimal cut-off of WHtR for detecting arterial stiffness was 0.49 in females and 0.53 in males, that of BRI was 3.19 in females and 3.89 in males. CONCLUSIONS: WHtR, ABSI and BRI were significantly associated with arterial stiffness. BRI and WHtR, rather than ABSI, showed superior predictive abilities for arterial stiffness in both sexes.


Asunto(s)
Adiposidad , Antropometría/métodos , Enfermedades Cardiovasculares/diagnóstico , Obesidad/diagnóstico , Rigidez Vascular , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Índice Tobillo Braquial , Área Bajo la Curva , Pueblo Asiatico , Índice de Masa Corporal , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/fisiopatología , Distribución de Chi-Cuadrado , China , Estudios Transversales , Femenino , Humanos , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Obesidad/epidemiología , Obesidad/fisiopatología , Oportunidad Relativa , Valor Predictivo de las Pruebas , Análisis de la Onda del Pulso , Curva ROC , Reproducibilidad de los Resultados , Factores de Riesgo , Factores Sexuales , Circunferencia de la Cintura , Relación Cintura-Estatura , Adulto Joven
14.
Stem Cells Transl Med ; 6(9): 1803-1814, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28650520

RESUMEN

Recent reports have indicated human embryonic stem cells-derived midbrain dopamine (mDA) neurons as proper cell resources for use in Parkinson's disease (PD) therapy. Nevertheless, no detailed and systematic study has been conducted to identify which differentiation stages of mDA cells are most suitable for transplantation in PD therapy. Here, we transplanted three types of mDA cells, DA progenitors (differentiated in vitro for 16 days [D16]), immature DA neurons (D25), and DA neurons (D35), into PD mice and found that all three types of cells showed high viability and strong neuronal differentiation in vivo. Both D25 and D35 cells showed neuronal maturation and differentiation toward TH+ cells and, accordingly, satisfactory behavioral functional recovery. However, transplanted D16 cells were less capable of producing functional recovery. These findings provide a valuable guideline for standardizing the differentiation stage of the transplantable cells used in clinical cell therapy for PD. Stem Cells Translational Medicine 2017;6:1803-1814.


Asunto(s)
Neuronas Dopaminérgicas/citología , Mesencéfalo/citología , Células-Madre Neurales/citología , Enfermedad de Parkinson/terapia , Trasplante de Células Madre/métodos , Animales , Células Cultivadas , Neuronas Dopaminérgicas/trasplante , Humanos , Masculino , Ratones , Ratones Endogámicos NOD , Ratones SCID , Células-Madre Neurales/trasplante , Neurogénesis
15.
Sci Rep ; 6: 23964, 2016 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-27050297

RESUMEN

Cerebral hypoperfusion and impaired autophagy are two etiological factors that have been identified as being associated with the development of Alzheimer's disease (AD). Nevertheless, the exact relationships among these pathological processes remain unknown. To elucidate the impact of cerebral hypoperfusion in AD, we created a unilateral common carotid artery occlusion (UCCAO) model by occluding the left common carotid artery in both young and old 3xTg-AD mice. Two months after occlusion, we found that ligation increases phospho-Tau (p-Tau) at Serine 199/202 in the hippocampus of 3-month-old AD mice, compared to sham-operated AD mice; whereas, there is no change in the wild type (WT) mice after ligation. Moreover, cerebral hypoperfusion led to significant increase of p-Tau in both the hippocampus and cortex of 16-month-old AD mice and WT mice. Notably, we did not detect any change in Aß42 level in either young or old AD and WT mice after ligation. Interestingly, we observed a downregulation of LC3-II in the cortex of aged AD mice and WT mice after ligation. Our results suggest that elevated p-Tau and reduced autophagy are major cellular changes that are associated with hypoperfusion in AD. Therefore, targeting p-Tau and autophagy pathways may ameliorate hypoperfusion-induced brain damage in AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Autofagia , Isquemia Encefálica/metabolismo , Proteínas tau/metabolismo , Factores de Edad , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/metabolismo , Animales , Isquemia Encefálica/genética , Enfermedad Crónica , Modelos Animales de Enfermedad , Femenino , Lóbulo Frontal/metabolismo , Hipocampo/metabolismo , Humanos , Immunoblotting , Masculino , Ratones de la Cepa 129 , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Asociadas a Microtúbulos/metabolismo , Fragmentos de Péptidos/metabolismo , Fosforilación
16.
Elife ; 52016 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-26883496

RESUMEN

During the development, tight regulation of the expansion of neural progenitor cells (NPCs) and their differentiation into neurons is crucial for normal cortical formation and function. In this study, we demonstrate that microRNA (miR)-128 regulates the proliferation and differentiation of NPCs by repressing pericentriolar material 1 (PCM1). Specifically, overexpression of miR-128 reduced NPC proliferation but promoted NPC differentiation into neurons both in vivo and in vitro. In contrast, the reduction of endogenous miR-128 elicited the opposite effects. Overexpression of miR-128 suppressed the translation of PCM1, and knockdown of endogenous PCM1 phenocopied the observed effects of miR-128 overexpression. Furthermore, concomitant overexpression of PCM1 and miR-128 in NPCs rescued the phenotype associated with miR-128 overexpression, enhancing neurogenesis but inhibiting proliferation, both in vitro and in utero. Taken together, these results demonstrate a novel mechanism by which miR-128 regulates the proliferation and differentiation of NPCs in the developing neocortex.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Diferenciación Celular , Proliferación Celular , Corteza Cerebral/embriología , Regulación de la Expresión Génica , MicroARNs/metabolismo , Células-Madre Neurales/fisiología , Animales , Corteza Cerebral/citología , Ratones Endogámicos C57BL , Células-Madre Neurales/citología
17.
Cell Transplant ; 25(7): 1343-57, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26720780

RESUMEN

Neuronal progenitor cells (NPCs) derived from human embryonic stem cells (hESCs) are an excellent cell source for transplantation therapy due to their availability and ethical acceptability. However, the traditional method of expansion and differentiation of hESCs into NPCs in monolayer cultures requires a long time, and the cell yield is low. A microcarrier (MC) platform can improve the expansion of hESCs and increase the yield of NPCs. In this study, for the first time, we transplanted microcarrier-expanded hESC-derived NPCs into the striatum of adult NOD-SCID IL2Rgc null mice, either as single cells or as cell aggregates. The recipient mice were perfused, and the in vivo survival, differentiation, and targeted innervation of the transplanted cells were assessed by immunostaining. We found that both the transplanted single NPCs and aggregate NPCs were able to survive 1 month posttransplantation, as revealed by human-specific neural cell adhesion molecule (NCAM) and human nuclear antigen staining. Compared to the single cells, the transplanted cell aggregates showed better survival over a 3-month period. In addition, both the transplanted single NPCs and the aggregate NPCs were able to differentiate into DCX-positive immature neurons and Tuj1-positive neurons in vivo by 1 month posttransplantation. However, only the transplantation of aggregate NPCs was shown to result in mature neurons at 3 months posttransplantation. Furthermore, we found that the cell aggregates were able to send long axons to innervate their targets. Our study provides preclinical evidence that the use of MCs to expand and differentiate hESC-derived NPCs and transplantation of these cells as aggregates produce longer survival in vivo.


Asunto(s)
Diferenciación Celular , Microesferas , Células-Madre Neurales/citología , Células-Madre Neurales/trasplante , Animales , Agregación Celular , Proliferación Celular , Supervivencia Celular , Neuronas Dopaminérgicas/citología , Proteína Doblecortina , Células Madre Embrionarias Humanas/citología , Humanos , Masculino , Ratones Endogámicos NOD , Ratones SCID , Neuritas/metabolismo , Factores de Tiempo
18.
Adv Exp Med Biol ; 888: 85-105, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26663180

RESUMEN

microRNAs (miRNAs) are small, noncoding RNA molecules that through imperfect base-pairing with complementary sequences of target mRNA molecules, typically cleave target mRNA, causing subsequent degradation or translation inhibition. Although an increasing number of studies have identified misregulated miRNAs in the neurodegenerative diseases (NDDs) Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, which suggests that alterations in the miRNA regulatory pathway could contribute to disease pathogenesis, the molecular mechanisms underlying the pathological implications of misregulated miRNA expression and the regulation of the key genes involved in NDDs remain largely unknown. In this chapter, we provide evidence of the function and regulation of miRNAs and their association with the neurological events in NDDs. This will help improve our understanding of how miRNAs govern the biological functions of key pathogenic genes in these diseases, which potentially regulate several pathways involved in the progression of neurodegeneration. Additionally, given the growing interest in the therapeutic potential of miRNAs, we discuss current clinical challenges to developing miRNA-based therapeutics for NDDs.


Asunto(s)
Regulación de la Expresión Génica , MicroARNs/genética , Enfermedades Neurodegenerativas/genética , Transducción de Señal/genética , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/terapia , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/terapia , Humanos , Enfermedad de Huntington/genética , Enfermedad de Huntington/terapia , Enfermedades Neurodegenerativas/terapia , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/terapia
19.
J Neurochem ; 135(3): 492-507, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26195140

RESUMEN

Multiple C2 domains transmembrane protein 1 (MCTP1) contains two transmembrane regions and three C2 domains of high Ca(2+)-binding affinity. Single-nucleotide polymorphism (SNP) of human MCTP1 gene is reportedly associated with bipolar disorder, but expression and function of MCTP1 in the CNS is still largely unknown. We cloned rat MCTP1 isoforms, and studied expression of MCTP1 transcript and protein in the CNS. Subcellular distribution and functional roles of MCTP1 were investigated in cultured primary neurons or PC12 cells by over-expression, cell imaging, and flow cytometry. MCTP1 immunostaining was seen in both CNS neuronal cell bodies and processes, especially in the hippocampus, dentate gyrus, medial habenular nucleus, amygdala, and selected cerebral and cerebellar cortical areas/layers. Under an electron microscope, MCTP1 immunoreactivity was observed on vesicles in neuronal cell bodies and pre-synaptic axon terminals. In cultured primary neurons and PC12 cells MCTP1 was detected on selected populations of secretory vesicles and endosomes. MCTP1 over-expression significantly inhibited neuronal transferrin endocytosis, secretory vesicle retrieval, cell migration, and oxidative stress from glutamate toxicity. Thus MCTP1 might be involved in regulating endocytic recycling of specific CNS neurons and synapses. MCTP1 abnormality might cause altered synaptic vesicle recycling, and thereby lead to vulnerability to neuropsychiatric diseases.


Asunto(s)
Sistema Nervioso Central/metabolismo , Proteínas de la Membrana/biosíntesis , Neuronas/metabolismo , Estrés Oxidativo/fisiología , Vesículas Sinápticas/fisiología , Animales , Células Cultivadas , Sistema Nervioso Central/ultraestructura , Femenino , Regulación de la Expresión Génica , Humanos , Masculino , Neuronas/ultraestructura , Células PC12 , Embarazo , Conejos , Ratas , Ratas Wistar
20.
ACS Chem Neurosci ; 5(10): 884-94, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25210999

RESUMEN

MicroRNAs (miRNAs) are single stranded, noncoding RNA molecules that are encoded by eukaryotic nuclear DNA. miRNAs function through imperfect base-pairing with complementary sequences of target mRNA molecules, which is typically via the cleavage of target mRNA with transcriptional repression or translational degradation. An increasing number of studies identified dysregulation of miRNAs in neurodegenerative disease and suggest that alterations in the miRNA regulatory pathway could contribute to the disease pathogenesis. However, molecular mechanisms underlying the pathological implications of dysregulated miRNA expression and regulation of the key genes that are involved in neurodegenerative diseases remain largely unknown. Here, we review the evidence for the functional role of dysregulated miRNAs involved in disease pathogenesis, as well as how miRNAs govern neuronal functions either upstream or downstream of target genes that are disease pathogenic factors. Furthermore, we review the cellular feedback regulation between miRNAs and target genes in neurodegenerative diseases, with a focus on Alzheimer's disease and Parkinson's disease.


Asunto(s)
Enfermedad de Alzheimer/fisiopatología , MicroARNs/metabolismo , Enfermedad de Parkinson/fisiopatología , Animales , Humanos , Neuronas/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...