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2.
Biotechnol J ; 14(7): e1800606, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30927490

RESUMEN

Active hemostatic agents can play a crucial role in saving patients' lives during surgery. Active hemostats have several advantages including utilization of natural blood coagulation and biocompatibility. Among them, although human neutrophil peptide-1 (HNP-1) has been previously reported with the hemostatic mechanism, which part of HNP-1 facilitates the hemostatic activity is not known. Here, a partial peptide (HNP-F) promoting hemostasis, originating from HNP-1, has been newly identified by the blood coagulation ability test. HNP-F shows the best hemostatic effect between the anterior half and posterior half of peptides. Moreover, microscopic images show platelet aggregation and an increase in the concentration of platelet factor 4, and the scanning electron microscope image of platelets support platelet activation by HNP-F. Thromboelastography indicates decreased clotting time and increased physical properties of blood clotting. Mouse liver experiments demonstrate improved hemostatic effect by treatment of peptide solution. Cell viability and hemolysis assays confirm the HNP-F's biosafety. It is hypothesized that the surface charge and structure of HNP-F could be favorable to interact with fibrinogen or thrombospondin-1. Collectively, because HNP-F as an active peptide hemostat has many advantages, it could be expected to become a potent hemostatic biomaterial, additive or pharmaceutical candidate for various hemostatic applications.


Asunto(s)
Hemostasis/efectos de los fármacos , alfa-Defensinas , Animales , Supervivencia Celular/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/farmacología , Tromboelastografía , alfa-Defensinas/química , alfa-Defensinas/genética , alfa-Defensinas/farmacología
3.
Neuropsychopharmacology ; 44(2): 314-323, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29899405

RESUMEN

Autism spectrum disorder (ASD) is a neurodevelopmental disorder, featuring social communication deficit and repetitive/restricted behaviors as common symptoms. Its prevalence has continuously increased, but, till now, there are no therapeutic approaches to relieve the core symptoms, particularly social deficit. In previous studies, abnormal function of the glutamatergic neural system has been proposed as a critical mediator and therapeutic target of ASD-associated symptoms. Here, we investigated the possible roles of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) in autism symptoms using two well-known autistic animal models, Cntnap2 knockout (KO) mice and in utero valproic acid-exposed ICR (VPA) mice. We found that Cntnap2 KO mice displayed decreased glutamate receptor expression and transmission. Contrarily, VPA mice exhibited increased glutamate receptor expression and transmission. Next, we investigated whether AMPAR modulators (positive-allosteric-modulator for Cntnap2 KO mice and antagonist for VPA mice) can improve autistic symptoms by normalizing the aberrant excitatory transmission in the respective animal models. Interestingly, the AMPAR modulation specifically ameliorated social deficits in both animal models. These results indicated that AMPAR-derived excitatory neural transmission changes can affect normal social behavior. To validate this, we injected an AMPAR agonist or antagonist in control ICR mice and, interestingly, these treatments impaired only the social behavior, without affecting the repetitive and hyperactive behaviors. Collectively, these results provide insight into the role of AMPARs in the underlying pathophysiological mechanisms of ASD, and demonstrate that modulation of AMPAR can be a potential target for the treatment of social behavior deficits associated with ASD.


Asunto(s)
Trastorno del Espectro Autista/tratamiento farmacológico , Conducta Animal/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/uso terapéutico , Receptores AMPA/antagonistas & inhibidores , Conducta Social , Animales , Trastorno del Espectro Autista/inducido químicamente , Trastorno del Espectro Autista/genética , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Antagonistas de Aminoácidos Excitadores/farmacología , Femenino , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Técnicas de Placa-Clamp , Juego e Implementos de Juego , Embarazo , Efectos Tardíos de la Exposición Prenatal , Receptores de N-Metil-D-Aspartato/metabolismo , Ácido Valproico
4.
Mol Cells ; 41(5): 486-494, 2018 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-29696935

RESUMEN

Recently, we have reported that animals with telomerase reverse transcriptase (TERT) overexpression exhibit reduced social interaction, decreased preference for novel social interaction and poor nest-building behaviors symptoms that mirror those observed in human autism spectrum disorders (ASD). Overexpression of TERT also alters the excitatory/inhibitory (E/I) ratio in the medial prefrontal cortex. However, the effects of TERT overexpression on hippocampal-dependent learning and synaptic efficacy have not been investigated. In the present study, we employed electrophysiological approaches in combination with behavioral analysis to examine hippocampal function of TERT transgenic (TERT-tg) mice and FVB controls. We found that TERT overexpression results in enhanced hippocampal excitation with no changes in inhibition and significantly impairs long-term synaptic plasticity. Interestingly, the expression levels of phosphorylated CREB and phosphory-lated CaMKIIα were significantly decreased while the expression level of CaMKIIα was slightly increased in the hippocampus of TERT-overexpressing mice. Our observations highlight the importance of TERT in normal synaptic function and behavior and provide additional information on a novel animal model of ASD associated with TERT overexpression.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Modelos Animales de Enfermedad , Plasticidad Neuronal , Células Piramidales/fisiología , Transmisión Sináptica , Telomerasa/fisiología , Animales , Trastorno del Espectro Autista/enzimología , Región CA1 Hipocampal/enzimología , Región CA1 Hipocampal/fisiología , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/biosíntesis , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/biosíntesis , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/genética , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciales Postsinápticos Excitadores/fisiología , Expresión Génica , Hipocampo/enzimología , Potenciales Postsinápticos Inhibidores/efectos de los fármacos , Potenciales Postsinápticos Inhibidores/fisiología , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Aprendizaje por Laberinto/fisiología , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/genética , Neurotoxinas/farmacología , Técnicas de Placa-Clamp , Células Piramidales/efectos de los fármacos , Células Piramidales/enzimología , Proteínas Recombinantes/metabolismo , Transmisión Sináptica/efectos de los fármacos , Telomerasa/genética , Tetrodotoxina/farmacología
5.
Biomol Ther (Seoul) ; 26(5): 439-445, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29463073

RESUMEN

T-type calcium channels are low voltage-activated calcium channels that evoke small and transient calcium currents. Recently, T-type calcium channels have been implicated in neurodevelopmental disorders such as autism spectrum disorder and neural tube defects. However, their function during embryonic development is largely unknown. Here, we investigated the function and expression of T-type calcium channels in embryonic neural progenitor cells (NPCs). First, we compared the expression of T-type calcium channel subtypes (CaV3.1, 3.2, and 3.3) in NPCs and differentiated neural cells (neurons and astrocytes). We detected all subtypes in neurons but not in astrocytes. In NPCs, CaV3.1 was the dominant subtype, whereas CaV3.2 was weakly expressed, and CaV3.3 was not detected. Next, we determined CaV3.1 expression levels in the cortex during early brain development. Expression levels of CaV3.1 in the embryonic period were transiently decreased during the perinatal period and increased at postnatal day 11. We then pharmacologically blocked T-type calcium channels to determine the effects in neuronal cells. The blockade of T-type calcium channels reduced cell viability, and induced apoptotic cell death in NPCs but not in differentiated astrocytes. Furthermore, blocking T-type calcium channels rapidly reduced AKT-phosphorylation (Ser473) and GSK3ß-phosphorylation (Ser9). Our results suggest that T-type calcium channels play essential roles in maintaining NPC viability, and T-type calcium channel blockers are toxic to embryonic neural cells, and may potentially be responsible for neurodevelopmental disorders.

6.
Biochem Biophys Res Commun ; 495(1): 1214-1220, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29180007

RESUMEN

The high concentrations of nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) in activated glial cells in response to neuroinflammatory stimuli have neurotoxic effects on the brain. At basal levels, iNOS expression is low, and proinflammatory stimuli induce iNOS expression in astrocytes, microglia, and oligodendrocytes. Fyn, a non-receptor tyrosine kinase, regulates iNOS expression in several types of immune cells. However, its role in stimulated astrocytes is less clear. In this study, we investigated the role of Fyn in the regulation of lipopolysaccharide (LPS)-induced iNOS expression in astrocytes from mice and rats. Intracerebroventricular LPS injections in cortical regions enhanced iNOS mRNA and protein levels, which were increased in Fyn-deficient mice. Accordingly, LPS-induced nitrite production was enhanced in primary astrocytes cultured from Fyn-deficient mice or rats. Similar results were observed in cultured astrocytes after the siRNA-induced knockdown of Fyn expression. Finally, we observed increased LPS-induced extracellular signal-regulated protein kinase (ERK) activation in Fyn-deficient astrocytes. These results suggested that Fyn has a regulatory role in iNOS expression in astrocytes during neuroinflammatory responses.


Asunto(s)
Astrocitos/inmunología , Quinasas MAP Reguladas por Señal Extracelular/inmunología , Regulación Enzimológica de la Expresión Génica/inmunología , Mediadores de Inflamación/inmunología , Lipopolisacáridos/farmacología , Óxido Nítrico Sintasa de Tipo II/inmunología , Proteínas Proto-Oncogénicas c-fyn/inmunología , Animales , Astrocitos/efectos de los fármacos , Células Cultivadas , Sistema de Señalización de MAP Quinasas/inmunología , Ratones , Ratones Noqueados , Fosforilación/efectos de los fármacos , Ratas , Ratas Sprague-Dawley
7.
Exp Neurobiol ; 26(5): 252-265, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29093634

RESUMEN

The valproic acid (VPA)-induced animal model is one of the most widely utilized environmental risk factor models of autism. Autism spectrum disorder (ASD) remains an insurmountable challenge among neurodevelopmental disorders due to its heterogeneity, unresolved pathological pathways and lack of treatment. We previously reported that VPA-exposed rats and cultured rat primary neurons have increased Pax6 expression during post-midterm embryonic development which led to the sequential upregulation of glutamatergic neuronal markers. In this study, we provide experimental evidence that telomerase reverse transcriptase (TERT), a protein component of ribonucleoproteins complex of telomerase, is involved in the abnormal components caused by VPA in addition to Pax6 and its downstream signals. In embryonic rat brains and cultured rat primary neural progenitor cells (NPCs), VPA induced the increased expression of TERT as revealed by Western blot, RT-PCR, and immunostainings. The HDAC inhibitor property of VPA is responsible for the TERT upregulation. Chromatin immunoprecipitation revealed that VPA increased the histone acetylation but blocked the HDAC1 binding to both Pax6 and Tert genes. Interestingly, the VPA-induced TERT overexpression resulted to sequential upregulations of glutamatergic markers such as Ngn2 and NeuroD1, and inter-synaptic markers such as PSD-95, α-CaMKII, vGluT1 and synaptophysin. Transfection of Tert siRNA reversed the effects of VPA in cultured NPCs confirming the direct involvement of TERT in the expression of those markers. This study suggests the involvement of TERT in the VPA-induced autistic phenotypes and has important implications for the role of TERT as a modulator of balanced neuronal development and transmission in the brain.

8.
Biomol Ther (Seoul) ; 25(4): 374-382, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28208013

RESUMEN

Autism spectrum disorder (ASD) remains unexplained and untreated despite the high attention of research in recent years. Aside from its various characteristics is the baffling male preponderance over the female population. Using a validated animal model of ASD which is the telomerase reverse transcriptase overexpressing mice (TERT-tg), we conducted ASD-related behavioral assessments and protein expression experiments to mark the difference between male and females of this animal model. After statistically analyzing the results, we found significant effects of TERT overexpression in sociability, social novelty preference, anxiety, nest building, and electroseizure threshold in the males but not their female littermates. Along these differences are the male-specific increased expressions of postsynaptic proteins which are the NMDA and AMPA receptors in the prefrontal cortex. The vGluT1 presynaptic proteins, but not GAD, were upregulated in both sexes of TERT-tg mice, although it is more significantly pronounced in the male group. Here, we confirmed that the behavioral effect of TERT overexpression in mice was male-specific, suggesting that the aberration of this gene and its downstream pathways preferentially affect the functional development of the male brain, consistent with the male preponderance in ASD.

10.
Neuropharmacology ; 113(Pt A): 71-81, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27638451

RESUMEN

Autism spectrum disorder (ASD) is an immensely challenging developmental disorder characterized primarily by two core behavioral symptoms of social communication deficits and restricted/repetitive behaviors. Investigating the etiological process and identifying an appropriate therapeutic target remain as formidable challenges to overcome ASD due to numerous risk factors and complex symptoms associated with the disorder. Among the various mechanisms that contribute to ASD, the maintenance of excitation and inhibition balance emerged as a key factor to regulate proper functioning of neuronal circuitry. Interestingly, our previous study involving the valproic acid animal model of autism (VPA animal model) has demonstrated excitatory-inhibitory imbalance (E/I imbalance) due to enhanced differentiation of glutamatergic neurons and reduced GABAergic neurons. Here, we investigated the potential of agmatine, an endogenous NMDA receptor antagonist, as a novel therapeutic candidate in ameliorating ASD symptoms by modulating E/I imbalance using the VPA animal model. We observed that a single treatment of agmatine rescued the impaired social behaviors as well as hyperactive and repetitive behaviors in the VPA animal model. We also observed that agmatine treatment rescued the overly activated ERK1/2 signaling in the prefrontal cortex and hippocampus of VPA animal models, possibly, by modulating over-excitability due to enhanced excitatory neural circuit. Taken together, our results have provided experimental evidence suggesting a possible therapeutic role of agmatine in ameliorating ASD-like symptoms in the VPA animal model of ASD.


Asunto(s)
Agmatina/administración & dosificación , Trastorno del Espectro Autista/tratamiento farmacológico , Trastorno del Espectro Autista/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Agmatina/uso terapéutico , Animales , Trastorno del Espectro Autista/inducido químicamente , Modelos Animales de Enfermedad , Aseo Animal/efectos de los fármacos , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Hipercinesia/prevención & control , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Ratones , Ratones Transgénicos , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Cultivo Primario de Células , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Convulsiones/prevención & control , Conducta Social , Ácido Valproico
11.
Sci Rep ; 6: 36250, 2016 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-27819277

RESUMEN

Autism spectrum disorder (ASD) is a heterogeneously pervasive developmental disorder in which various genetic and environmental factors are believed to underlie its development. Recently, epigenetics has been suggested as a novel concept for ASD aetiology with a proposition that epigenetic marks can be transgenerationally inherited. Based on this assumption of epigenetics, we investigated the transgenerational inheritance of ASD-like behaviours and their related synaptic changes in the VPA animal model of ASD. The first generation (F1) VPA-exposed offspring exhibited autistic-like impaired sociability and increased marble burying. They also showed increased seizure susceptibility, hyperactivity and decreased anxiety. We mated the VPA-exposed F1 male offspring with naïve females to produce the second generation (F2), and then similarly mated the F2 to deliver the third generation (F3). Remarkably, the autism-like behavioural phenotypes found in F1 persisted to the F2 and F3. Additionally, the frontal cortices of F1 and F3 showed some imbalanced expressions of excitatory/inhibitory synaptic markers, suggesting a transgenerational epigenetic inheritance. These results open the idea that E/I imbalance and ASD-like behavioural changes induced by environmental insults in mice can be epigenetically transmitted, at least, to the third generation. This study could help explain the unprecedented increase in ASD prevalence.


Asunto(s)
Trastorno del Espectro Autista , Conducta Animal/efectos de los fármacos , Lóbulo Frontal , Exposición Materna/efectos adversos , Ácido Valproico/efectos adversos , Animales , Trastorno del Espectro Autista/inducido químicamente , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/metabolismo , Trastorno del Espectro Autista/fisiopatología , Femenino , Lóbulo Frontal/metabolismo , Lóbulo Frontal/fisiopatología , Masculino , Ratones , Ratones Endogámicos ICR , Embarazo , Ácido Valproico/farmacología
12.
Biomol Ther (Seoul) ; 24(3): 207-43, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27133257

RESUMEN

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and communication impairments, as well as repetitive and restrictive behaviors. The phenotypic heterogeneity of ASD has made it overwhelmingly difficult to determine the exact etiology and pathophysiology underlying the core symptoms, which are often accompanied by comorbidities such as hyperactivity, seizures, and sensorimotor abnormalities. To our benefit, the advent of animal models has allowed us to assess and test diverse risk factors of ASD, both genetic and environmental, and measure their contribution to the manifestation of autistic symptoms. At a broader scale, rodent models have helped consolidate molecular pathways and unify the neurophysiological mechanisms underlying each one of the various etiologies. This approach will potentially enable the stratification of ASD into clinical, molecular, and neurophenotypic subgroups, further proving their translational utility. It is henceforth paramount to establish a common ground of mechanistic theories from complementing results in preclinical research. In this review, we cluster the ASD animal models into lesion and genetic models and further classify them based on the corresponding environmental, epigenetic and genetic factors. Finally, we summarize the symptoms and neuropathological highlights for each model and make critical comparisons that elucidate their clinical and neurobiological relevance.

13.
Mol Neurobiol ; 53(10): 7312-7328, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-26696493

RESUMEN

In addition to its classical role as a regulator of telomere length, recent reports suggest that telomerase reverse transcriptase (TERT) plays a role in the transcriptional regulation of gene expression such as ß-catenin-responsive pathways. Silencing or over-expression of TERT in cultured NPCs demonstrated that TERT induced glutamatergic neuronal differentiation. During embryonic brain development, expression of transcription factors involved in glutamatergic neuronal differentiation was increased in mice over-expressing TERT (TERT-tg mice). We observed increased expression of NMDA receptor subunits and phosphorylation of α-CaMKII in TERT-tg mice. TERT-tg mice showed autism spectrum disorder (ASD)-like behavioral phenotypes as well as lowered threshold against electrically induced seizure. Interestingly, the NMDA receptor antagonist memantine restored behavioral abnormalities in TERT-tg mice. Consistent with the alteration in excitatory/inhibitory (E/I) ratio, TERT-tg mice showed autism-like behaviors, abnormal synaptic organization, and function in mPFC suggesting the role of altered TERT activity in the manifestation of ASD, which is further supported by the significant association of certain SNPs in Korean ASD patients.


Asunto(s)
Trastorno Autístico/enzimología , Trastorno Autístico/patología , Telomerasa/metabolismo , Animales , Trastorno Autístico/tratamiento farmacológico , Conducta Animal , Encéfalo/embriología , Diferenciación Celular , Células Cultivadas , Desarrollo Embrionario , Técnicas de Silenciamiento del Gen , Silenciador del Gen , Glutamatos/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Memantina/farmacología , Memantina/uso terapéutico , Ratones Transgénicos , Neuronas/metabolismo , Neuronas/ultraestructura , Fenotipo , ARN Interferente Pequeño/metabolismo , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapsis/metabolismo , Sinapsis/ultraestructura , Factores de Transcripción/metabolismo
14.
Mol Neurobiol ; 53(1): 40-56, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25404090

RESUMEN

Males are predominantly affected by autism spectrum disorders (ASD) with a prevalence ratio of 5:1. However, the underlying pathological mechanisms governing the male preponderance of ASD remain unclear. Recent studies suggested that epigenetic aberrations may cause synaptic dysfunctions, which might be related to the pathophysiology of ASD. In this study, we used rat offspring prenatally exposed to valproic acid (VPA) as an animal model of ASD. We found male-selective abnormalities in the kinetic profile of the excitatory glutamatergic synaptic protein expressions linked to N-methyl-D-aspartate receptor (NMDAR), alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) and metabotropic glutamate receptor 5 (mGluR5) pathways in the prefrontal cortex of the VPA-exposed offspring at postnatal weeks 1, 2, and 4. Furthermore, VPA exposure showed a male-specific attenuation of the methyl-CpG-binding protein 2 (MeCP2) expressions both in the prefrontal cortex of offspring and in the gender-isolated neural progenitor cells (NPCs). In the gender-isolated NPCs culture, higher concentration of VPA induced an increased glutamatergic synaptic development along with decreased MeCP2 expression in both genders suggesting the role of MeCP2 in the modulation of synaptic development. In the small interfering RNA (siRNA) knock-down study, 50 pmol of Mecp2 siRNA inhibited the MeCP2 expression in male- but not in female-derived NPCs with concomitant induction of postsynaptic proteins such as PSD95. Taken together, we suggest that the male-inclined reduction of MeCP2 expression is involved in the abnormal development of glutamatergic synapse and male preponderance in the VPA animal models of ASD.


Asunto(s)
Trastorno Autístico/metabolismo , Conducta Animal/efectos de los fármacos , Proteína 2 de Unión a Metil-CpG/metabolismo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Caracteres Sexuales , Sinapsis/metabolismo , Ácido Valproico/farmacología , Animales , Modelos Animales de Enfermedad , Femenino , Embarazo , Efectos Tardíos de la Exposición Prenatal/patología , Ratas Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo
15.
Exp Neurobiol ; 24(4): 285-300, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26713077

RESUMEN

The valproic acid (VPA) animal model of autism spectrum disorder (ASD) is one of the most widely used animal model in the field. Like any other disease models, it can't model the totality of the features seen in autism. Then, is it valid to model autism? This model demonstrates many of the structural and behavioral features that can be observed in individuals with autism. These similarities enable the model to define relevant pathways of developmental dysregulation resulting from environmental manipulation. The uncovering of these complex pathways resulted to the growing pool of potential therapeutic candidates addressing the core symptoms of ASD. Here, we summarize the validity points of VPA that may or may not qualify it as a valid animal model of ASD.

16.
J Nutr Biochem ; 26(12): 1520-6, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26452319

RESUMEN

In recent years, the average consumption of sugar in humans from all ages has remarkably increased, exceeding the recommended limit. Pregnancy is a critical time for the global development of offsprings who are vulnerable to the deleterious effects of environmental factors. In this study, we investigated whether high sucrose consumption during pregnancy could affect the attention-deficit hyperactivity disorder (ADHD)-like neurobehavioral outcomes in offspring mice. Pregnant mice were randomly grouped and orally administered with either water as control (Con) or 30% wt/vol sucrose diluted in water at 6 (Suc6) or 9 (Suc9) g/kg dosage per day from gestational days 6 to 15. After the weaning period, offspring mice underwent a series of behavioral testing for locomotor activity, attention, and impulsivity. Although there is no obvious difference in gross development of offspring mice such as weight gain, high sucrose-exposed offspring mice showed a significantly increased locomotor activity. Moreover, these mice exhibited a dose-dependent decrease in attention and increase in impulsivity. In the striatum, a significantly increased dopamine transporter (DAT) mRNA expression was found in the Suc9 group along with dose-dependent decreases in the Drd1, Drd2 and Drd4 dopamine receptor subtypes. Furthermore, synaptosomal DAT protein expression was increased about twofold in the Suc9 group. Prenatal fructose exposure also induced hyperactive behavior in offspring mice suggesting the essential role of fructose in the dysregulated neurobehavioral development. These findings suggest prenatal sucrose consumption as a new risk factor for ADHD, which may need further attention and investigation in humans.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/etiología , Efectos Tardíos de la Exposición Prenatal , Sacarosa/efectos adversos , Animales , Conducta Animal , Dieta , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Masculino , Aprendizaje por Laberinto , Ratones , Ratones Endogámicos ICR , Actividad Motora/efectos de los fármacos , Fenotipo , Embarazo , ARN Mensajero/metabolismo , Receptores Dopaminérgicos , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D4/metabolismo , Factores de Riesgo
17.
Int J Mol Sci ; 16(5): 9217-35, 2015 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-25915032

RESUMEN

The aim of this study was to investigate the effect of ethyl acetate fraction of Euryale ferox seed extracts (Efse-EA) on melanogenesis in immortalized mouse melanocyte cell line, melan-a. Efse-EA showed strong dose-dependent mushroom tyrosinase inhibitory activity. Treatment of melan-a cells with 30 µg/mL Efse-EA produced strong inhibition of cellular tyrosinase and melanin synthesis. Efse-EA significantly reduced the levels of melanogenesis-related proteins, such as tyrosinase, tyrosinase-related proteins 1 and 2, and microphthalmia-associated transcription factor. Because Efse-EA treatment reduced tyrosinase protein levels without changing its mRNA expression, we investigated whether this decrease was related to proteasomal or lysosomal degradation of tyrosinase. We found that chloroquine, a lysosomal proteolysis inhibitor, almost completely abolished both the down-regulation of tyrosinase and the inhibition of melanin synthesis induced by Efse-EA. These results suggested that Efse-EA may contribute to the inhibition of melanogenesis by altering lysosomal degradation of tyrosinase, and that this extract may provide a new cosmetic skin-whitening agent.


Asunto(s)
Lisosomas/metabolismo , Melanocitos/efectos de los fármacos , Melanocitos/metabolismo , Extractos Vegetales/farmacología , Semillas/química , Streptophyta/química , Animales , Antioxidantes/química , Antioxidantes/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Quelantes/química , Quelantes/farmacología , Cobre , Relación Dosis-Respuesta a Droga , Levodopa/metabolismo , Melaninas/metabolismo , Ratones , Monofenol Monooxigenasa/antagonistas & inhibidores , Extractos Vegetales/química
18.
Mol Neurobiol ; 52(1): 8-25, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25106729

RESUMEN

Plasminogen activator inhibitor-1 (PAI-1) is an endogenous inhibitor of tissue plasminogen activator (tPA) that acts as a neuromodulator in various neurophysiological and pathological conditions. Several researchers including us reported the induction of PAI-1 during inflammatory condition; however, the mechanism regulating PAI-1 induction is not yet clear. In this study, we investigated the role of non-receptor tyrosine kinase Fyn in the regulation of lipopolysaccharide (LPS)-induced upregulation of PAI-1 in rat primary astrocyte. The activation of toll-like receptor 4 (TLR4) signaling, induced by its ligand LPS, stimulated a physical interaction between TLR4 and Fyn along with phosphorylation of tyrosine residue in both molecules as determined by co-immunoprecipitation experiments. Immunofluorescence staining also showed increased co-localization of TLR4-Fyn on cultured rat primary astrocytes after LPS treatment. The increased TRLR4-Fyn interaction induced expression of PAI-1 through the activation of PI3k/Akt/NFĸB pathway. Treatment with Src kinase inhibitor (PP2) or transfection of Fyn small interfering RNA (siRNA) into cultured rat primary astrocytes inhibited phosphorylation of tyrosine residue of TLR4 and blocked the interaction between TLR4 and Fyn resulting to the inhibition of LPS-induced expression of PAI-1. The activation of PI3K/Akt/NFĸB signaling cascades was also inhibited by Fyn knockdown in rat primary astrocytes. The induction of PAI-1 in rat primary astrocytes, which resulted in downregulation of tPA activity in culture supernatants, inhibited neurite outgrowth in cultured rat primary cortical neuron. The inhibition of neurite extension was prevented by PP2 or Fyn siRNA treatment in rat primary astrocytes. These results suggest the critical physiological role of TRL4-Fyn interaction in the modulation of PAI-1-tPA axis in astrocytes during neuroinflammatory responses such as ischemia/reperfusion injuries.


Asunto(s)
Astrocitos/metabolismo , Lipopolisacáridos/farmacología , Inhibidor 1 de Activador Plasminogénico/metabolismo , Proteínas Proto-Oncogénicas c-fyn/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Astrocitos/efectos de los fármacos , Bovinos , Células Cultivadas , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Técnicas de Silenciamiento del Gen , Inyecciones Intraventriculares , Masculino , Ratones Endogámicos C57BL , Modelos Biológicos , FN-kappa B/metabolismo , Neuritas/efectos de los fármacos , Neuritas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfotirosina/metabolismo , Unión Proteica/efectos de los fármacos , Pirimidinas/farmacología , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Familia-src Quinasas/metabolismo
19.
Biomol Ther (Seoul) ; 22(5): 406-13, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25414770

RESUMEN

A substantial proportion of patients with autism spectrum disorder (ASD) display hyperactivity as a comorbid symptom. Exposure to valproic acid (VPA) during pregnancy produces ASD-like core behavioral phenotypes as well as hyperactivity in offspring both in human and experimental animals, which makes it a plausible model to study ASD-related neurobiological processes. In this study, we examined the effects of two of currently available attention defecit hyperactivity disorder (ADHD) medications, methylphenidate (MPH) and atomoxetine (ATX) targeting dopamine and norepinephrine transporters (DAT and NET), respectively, on hyperactive behavior of prenatally VPA-exposed rat offspring. In the prefrontal cortex of VPA exposed rat offspring, both mRNA and protein expression of DAT was increased as compared with control. VPA function as a histone deacetylase inhibitor (HDACi) and chromatin immunoprecipitation experiments demonstrated that the acetylation of histone bound to DAT gene promoter was increased in VPA-exposed rat offspring suggesting epigenetic mechanism of DAT regulation. Similarly, the expression of NET was increased, possibly via increased histone acetylation in prefrontal cortex of VPA-exposed rat offspring. When we treated the VPA-exposed rat offspring with ATX, a NET selective inhibitor, hyperactivity was reversed to control level. In contrast, MPH that inhibits both DAT and NET, did not produce inhibitory effects against hyperactivity. The results suggest that NET abnormalities may underlie the hyperactive phenotype in VPA animal model of ASD. Profiling the pharmacological responsiveness as well as investigating underlying mechanism in multiple models of ASD and ADHD may provide more insights into the neurobiological correlates regulating the behavioral abnormalities.

20.
Korean J Intern Med ; 29(5): 630-6, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25228839

RESUMEN

BACKGROUND/AIMS: The treatment for steroid-refractory acute graft versus host disease (GVHD) after allogeneic stem cell transplantation (allo-SCT) needs to be standardized. We report our clinical experience with etanercept for steroid-refractory acute GVHD. METHODS: Eighteen patients who underwent allo-SCT and presented with steroid-refractory acute GVHD at Ajou University Hospital were studied retrospectively. They were given 25 mg of etanercept subcutaneously twice weekly for 4 weeks. The clinical responses were evaluated with regard to the severity of acute GVHD. RESULTS: The median patient age was 43.5 years. Using nonparametric tests, etanercept had a down-grading effect on acute GVHD (p = 0.005), although no patient experienced complete remission. Partial responses were seen in 80%, 17%, and 57% of grade II to IV patients, respectively. Skin and gut GVHD were well controlled with etanercept, whereas hepatic GVHD was not. Four patients died of fatal infections. No factors affecting the clinical outcome of etanercept were identified. CONCLUSIONS: Etanercept has a modest effect on steroid-refractory acute GVHD after allo-SCT, with tolerable side effects.


Asunto(s)
Enfermedad Injerto contra Huésped/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Inmunoglobulina G/uso terapéutico , Receptores del Factor de Necrosis Tumoral/uso terapéutico , Enfermedad Aguda , Adulto , Anciano , Aloinjertos , Etanercept , Femenino , Enfermedad Injerto contra Huésped/etiología , Humanos , Inmunoglobulina G/efectos adversos , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Esteroides/uso terapéutico , Adulto Joven
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