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1.
Life Sci ; 232: 116618, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31265854

RESUMO

AIMS: Mitochondrial dysfunction has been regarded as one of the hallmarks of cerebral ischemia-reperfusion injury. In previous studies, we have provided evidence that the extracellular signaling pathway (ERK) 1/2 inhibitor PD98059 improved the neurological deficits by modulating antioxidant and anti-apoptotic activities in rats subjected to cardiac arrest/cardiopulmonary resuscitation (CA/CPR). Since oxidative stress can activate mitochondria-dependent apoptosis and autophagy, we further explored the effects of PD98059 on mitochondria involved with apoptosis and autophagy in rat CA model. MATERIALS AND METHODS: We disposed PD98059 in CA/CPR rats, tested the mitochondrial-mediated apoptosis pathway in brain tissues at 24 h post-resuscitation by mitochondrial permeability transition pores (MPTP), cytochrome c (CytC), BCL-2, BAX, caspase-3, as well as autophagy by LC3, Beclin-1, and p62. Furthermore, we explored the relationship of dynamin-related protein 1 (Drp1) with apoptosis and autophagy. KEY FINDINGS: Our study showed that PD98059 decreased the openings of MPTP, CytC release, caspase3 activation, apoptotic indices, LC3-II, Beclin-1and increased P62. PD98059 also inhibited mitochondria-dependent apoptosis and the activity of autophagy in a dose-dependent manner in rat cerebral cortices at 24 h post-resuscitation. The generation of phosphorylated Drp1-616 was down-regulated accompanied by a decrease of TUNEL-positive cells and LC3 in dual immunostaining after PD98059 inhibited activation of ERK signaling pathway in a dose-dependent manner in rat cerebral cortices at 24 h post-resuscitation. SIGNIFICANCE: PD98059 protects the brain against mitochondrial-mediated apoptosis and autophagy at 24 h post-resuscitation in rats subjected to CA/CPR, which is linked with the downregulation of Drp1 expression.


Assuntos
Flavonoides/farmacologia , Parada Cardíaca/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Reanimação Cardiopulmonar , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Flavonoides/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
2.
An Acad Bras Cienc ; 91(2): e20181373, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241709

RESUMO

Fabry disease (FD) is an X-linked inherited disease and occurs due to mutations in GLA gene that encodes the α-galactosidase enzyme. Consequently, there is an accumulation of enzyme substrates, namely globotriaosylceramide (GB3). FD is a multisystemic disease, caused by storage of GB3 in vascular endothelia, with significant renal, cardiac and vascular involvement. The aim of this work was to evaluate the in vitro effect of GB3 on electron transport chain complexes (ETC) and redox parameters. Biochemical biomarkers were determined in homogenates of cerebral cortex, kidneys and liver of Wistar rats in the presence or absence of GB3 at concentrations of 3, 6, 9 and 12 mg/L. We found that GB3 caused an increase of ETC complexes II and IV activities, increased production of reactive species and decreased superoxide dismutase enzyme activity in homogenates of cerebral cortex. As well also increased production of reactive species and superoxide dismutase activity in kidney homogenates. The results obtained in our work suggest that GB3 interferes in ETC complexes II and IV activities, however, the magnitude of this increase seems to be too low to present a physiologically importance. However, the imbalance in cellular redox state indicating that these alterations may be involved in the pathophysiology of FD, mainly in renal and cerebral manifestations.


Assuntos
Córtex Cerebral/metabolismo , Transporte de Elétrons/efeitos dos fármacos , Doença de Fabry/metabolismo , Rim/metabolismo , Fígado/metabolismo , Oxirredução/efeitos dos fármacos , Triexosilceramidas/farmacologia , Animais , Modelos Animais de Doenças , Doença de Fabry/enzimologia , Masculino , Ratos , Ratos Wistar
3.
Nat Commun ; 10(1): 2396, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160561

RESUMO

Modern genetic studies indicate that human brain evolution is driven primarily by changes in gene regulation, which requires understanding the biological function of largely non-coding gene regulatory elements, many of which act in tissue specific manner. We leverage chromatin interaction profiles in human fetal and adult cortex to assign three classes of human-evolved elements to putative target genes. We find that human-evolved elements involving DNA sequence changes and those involving epigenetic changes are associated with human-specific gene regulation via effects on different classes of genes representing distinct biological pathways. However, both types of human-evolved elements converge on specific cell types and laminae involved in cerebral cortical expansion. Moreover, human evolved elements interact with neurodevelopmental disease risk genes, and genes with a high level of evolutionary constraint, highlighting a relationship between brain evolution and vulnerability to disorders affecting cognition and behavior. These results provide novel insights into gene regulatory mechanisms driving the evolution of human cognition and mechanisms of vulnerability to neuropsychiatric conditions.


Assuntos
Córtex Cerebral/embriologia , Epigênese Genética/genética , Evolução Molecular , Regulação da Expressão Gênica no Desenvolvimento/genética , Células-Tronco Neurais/metabolismo , Transtornos do Neurodesenvolvimento/genética , Encéfalo/embriologia , Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Predisposição Genética para Doença , Humanos , Elementos Reguladores de Transcrição/genética
4.
J Agric Food Chem ; 67(27): 7684-7693, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31203623

RESUMO

This study investigated the alleviative effect of caffeic acid (CA) on Alzheimer's disease (AD) pathogenesis and associated mechanisms in high-fat (HF) diet-induced hyperinsulinemic rats. The results of a Morris water maze indicated that, by administrating CA (30 mg/kg b.w./day) for 30 weeks, the memory and learning impairments in HF-induced hyperinsulinemic rats were significantly ameliorated. CA also enhanced superoxide dismutase and glutathione free radical scavenger activity in hyperinsulinemic rats. The Western blot data further confirmed that protein expressions of phosphorylated-glycogen synthase kinase 3ß (GSK3ß) were significantly increased, whereas the expression of phosphorylated-tau protein decreased in the hippocampus of rats administered with CA in comparison with the HF group. Moreover, the expression of amyloid precursor protein (APP) and ß-site APP cleaving enzyme were attenuated, subsequently lowering the level of ß-amyloid 1-42 (Aß 1-42) in the hippocampus of CA-treated hyperinsulinemic rats. CA also significantly increased the expression of synaptic proteins in HF rats.


Assuntos
Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Ácidos Cafeicos/administração & dosagem , Insulina/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Animais , Antioxidantes/química , Córtex Cerebral/química , Córtex Cerebral/enzimologia , Córtex Cerebral/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Glutationa/metabolismo , Glicogênio Sintase Quinase 3 beta/análise , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/química , Hipocampo/enzimologia , Hipocampo/metabolismo , Hiperinsulinismo/etiologia , Hiperinsulinismo/metabolismo , Masculino , Fosforilação , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Proteínas tau/análise , Proteínas tau/metabolismo
5.
Life Sci ; 231: 116517, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31150684

RESUMO

Our previous study indicated that microRNA 145 (miR-145) and its predicated target, erythropoietin-producing hepatoma (EPH) receptor A4 (EPHA4), was closely associated with ischemic stroke. In this study, we aimed to further explore their function in a model of oxygen-glucose deprivation (OGD). The expression of miR-145 in the blood of 44 patients with ischemic stroke and 37 normal controls was detected by qRT-PCR. After transfection with either the wild- or mutant-type pGL3-promoter EPHA4 3'UTR into the miR-145 mimic and miR-145 inhibitor, a dual-luciferase reporter assay was performed to explore the interaction between miR-145 and EPHA4. qRT-PCR and Western blot were performed to further explore the effects of miR-145 on EPHA4 expression after an miR-145 mimic, an miR-145 inhibitor or LV-sh-EPHA4 was transfected into cerebral cortical neurons. The expression of miR-145 was significantly upregulated in the blood of patients with ischemic stroke compared to that of normal controls. Dual-luciferase reporter assay, qRT-PCR and Western blot results indicated that miR-145 indeed targets EPHA4 through its 3'-UTR and regulates the expression level of EPHA4 at both the mRNA and protein levels. Moreover, the OGD model was successfully constructed, and miR-145 exerted a protective effects in cell viability in the OGD model by downregulating EPHA4. The expression of LOC105376244 could be regulated by the miR-145-EPHA4 interaction. MiR-145 exerted a protective effects in cell viability in the OGD model by downregulating EPHA4, which suggested their potential roles in ischemic stroke and requires further research.


Assuntos
Isquemia Encefálica/metabolismo , Córtex Cerebral/citologia , MicroRNAs/genética , Neurônios/citologia , Receptor EphA4/metabolismo , Idoso , Apoptose/efeitos dos fármacos , Isquemia Encefálica/patologia , Hipóxia Celular/fisiologia , Sobrevivência Celular/genética , Córtex Cerebral/metabolismo , Regulação para Baixo , Feminino , Glucose/metabolismo , Humanos , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Neurônios/metabolismo , Oxigênio/metabolismo , Cultura Primária de Células , RNA Mensageiro/metabolismo , Acidente Vascular Cerebral/metabolismo
6.
Chem Biol Interact ; 308: 279-287, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150628

RESUMO

The dose-dependent neuroprotective role of licorice-derived glycyrrhizin during subacute neuroterminal norepinephrine (NE) depletion was studied in rat brain. Experimental design included thirty 5-week-old male rats randomly divided into five groups. Compared to the saline-injected control group, the group receiving daily intraperitoneal injection of fusaric acid (FA; 5 mg/kg/b.w.) for 30 days showed pharmacological depletion of NE. The neuroprotective effects of three successively increasing oral doses of glycyrrhizin were examined in FA-treated rats. Neurochemical parameters and histo-/immunohistopathological changes in the hippocampus were examined. FA generated global hippocampal stress with altered neurobiochemical parameters, accompanied by immune-confirmed inflammatory tissue damage, and noticeable behavioral changes. Although glycyrrhizin after FA-induced intoxication did not correct the recorded drop in the NE level, it decreased the dopamine levels to control levels. Similarly, glycyrrhizin at a high dose restored the serotonin level to its normal value and blocked the FA-induced increase in the level of its metabolite, 5-hydroxyindoleacetic acid. The FA-induced rise in γ-aminobutyric acid (GABA) and histamine was alleviated after administration of a high dose of glycyrrhizin. This was accompanied by improvements in the bioenergetic status and neuronal regenerative capacity through recovery of ATP and brain-derived neurotrophic factor levels to the pre-intoxicated values. High doses of glycyrrhizin also ameliorated the FA-generated behavioral changes and oxidative damage, manifested by the reduction in the expression of cortical pro-apoptotic caspase 3 in the same group. This study suggests that glycyrrhizin can potentially mend most of the previously evoked neuronal damage induced by FA intoxication in the brain of an experimental rat model.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Ácido Glicirrízico/farmacologia , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Norepinefrina/metabolismo , Acetilcolinesterase/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Ácido Fusárico/toxicidade , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/patologia , Síndromes Neurotóxicas/veterinária , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Regulação para Cima/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo
7.
J Headache Pain ; 20(1): 45, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046659

RESUMO

Spreading depression (SD) is a slowly propagating wave of near-complete depolarization of neurons and glial cells across the cortex. SD is thought to contribute to the underlying pathophysiology of migraine aura, and possibly also an intrinsic brain activity causing migraine headache. Experimental models of SD have recapitulated multiple migraine-related phenomena and are considered highly translational. In this review, we summarize conventional and novel methods to trigger SD, with specific focus on optogenetic methods. We outline physiological triggers that might affect SD susceptibility, review a multitude of physiological, biochemical, and behavioral consequences of SD, and elaborate their relevance to migraine pathophysiology. The possibility of constructing a recurrent episodic or chronic migraine model using SD is also discussed.


Assuntos
Córtex Cerebral/fisiopatologia , Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Modelos Animais de Doenças , Transtornos de Enxaqueca/fisiopatologia , Animais , Córtex Cerebral/metabolismo , Humanos , Transtornos de Enxaqueca/metabolismo , Enxaqueca com Aura/metabolismo , Enxaqueca com Aura/fisiopatologia , Neurônios/metabolismo
8.
Mol Med Rep ; 19(6): 4597-4602, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059032

RESUMO

Ubiquilin­1 (Ubqln), a ubiquitin­like protein, regulates degradation of misfolded proteins and has been reported to have a crucial role in multiple pathologic and physiologic conditions. The current study was undertaken to investigate the expression of Ubqln in the brain of a neonatal hypoxia­ischemic (HI) brain injury model induced using the Rice method with some modifications. Mouse pups at postnatal day 7 day were used in this study. Pups underwent permanent ligation of the left common carotid artery and a consecutive hypoxic challenge (8% O2 and 92% N2 for 120 min). The expression of Ubqln in the brain of pups following HI was analyzed by immunofluorescence staining and western blot analysis. Immunofluorescence staining demonstrated that Ubqln was extensively distributed in the cerebral cortex and hippocampus, and Ubqln was expressed in neurons, astrocytes and microglia in the brains of the HI brain injury model mice. Western blot analyses revealed decreased expression of Ubqln in the HI penumbra of the mouse model compared with Ubqln in the sham control group. The results of this study revealed that HI alters the expression of Ubqln, thus may provide a novel understanding of role of Ubqln in neonatal hypoxic ischemic encephalopathy.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/genética , Regulação para Baixo , Hipóxia-Isquemia Encefálica/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Animais Recém-Nascidos , Astrócitos/metabolismo , Western Blotting , Lesões Encefálicas/genética , Lesões Encefálicas/metabolismo , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Feminino , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Masculino , Camundongos , Microglia/metabolismo , Neurônios/metabolismo
9.
Nat Med ; 25(5): 784-791, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31061540

RESUMO

Owing to recent medical and technological advances in neonatal care, infants born extremely premature have increased survival rates1,2. After birth, these infants are at high risk of hypoxic episodes because of lung immaturity, hypotension and lack of cerebral-flow regulation, and can develop a severe condition called encephalopathy of prematurity3. Over 80% of infants born before post-conception week 25 have moderate-to-severe long-term neurodevelopmental impairments4. The susceptible cell types in the cerebral cortex and the molecular mechanisms underlying associated gray-matter defects in premature infants remain unknown. Here we used human three-dimensional brain-region-specific organoids to study the effect of oxygen deprivation on corticogenesis. We identified specific defects in intermediate progenitors, a cortical cell type associated with the expansion of the human cerebral cortex, and showed that these are related to the unfolded protein response and changes. Moreover, we verified these findings in human primary cortical tissue and demonstrated that a small-molecule modulator of the unfolded protein response pathway can prevent the reduction in intermediate progenitors following hypoxia. We anticipate that this human cellular platform will be valuable for studying the environmental and genetic factors underlying injury in the developing human brain.


Assuntos
Lesões Encefálicas/etiologia , Hipóxia Encefálica/etiologia , Modelos Neurológicos , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Hipóxia Celular/genética , Hipóxia Celular/fisiologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Humanos , Hipóxia Encefálica/metabolismo , Hipóxia Encefálica/patologia , Lactente Extremamente Prematuro , Recém-Nascido , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Neurogênese/genética , Neurogênese/fisiologia , Organoides/metabolismo , Organoides/patologia , Proteínas com Domínio T/metabolismo , Resposta a Proteínas não Dobradas
10.
Croat Med J ; 60(2): 71-77, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31044578

RESUMO

AIM: To test the hypothesis that valproic acid treatment positively affects brain-derived neurotrophic factor (BDNF) expression and DNA methylation in the hippocampus and brain cortex of rats simultaneously treated with aldosterone. METHODS: Male Sprague-Dawley rats (N=40) were treated for two weeks with valproic acid (100 mg/1 kg body weight/d) in drinking water and aldosterone (2 µg/100 g body weight/d) or placebo via subcutaneous osmotic minipumps. RESULTS: Treatment with valproic acid did not modify BDNF gene expression in the hippocampus but reduced BDNF mRNA levels in the brain cortex. Valproic acid treatment marginally enhanced global DNA methylation in the frontal cortex. BDNF expression negatively correlated with DNA methylation in the hippocampus of valproic acid-treated rats. An unexpected finding was that aldosterone treatment significantly decreased global DNA methylation in the hippocampus. CONCLUSION: The effect of valproic acid on BDNF expression in the brain may depend on the extent of pathological changes present at the time of treatment onset. The observed negative correlation between BDNF expression and DNA methylation in the hippocampus of valproic acid-treated rats encourages further studies.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Metilação de DNA/efeitos dos fármacos , Depressão/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Ácido Valproico/farmacologia , Aldosterona , Animais , Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Depressão/induzido quimicamente , Modelos Animais de Doenças , Hipocampo/metabolismo , Masculino , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Ácido Valproico/uso terapêutico
11.
Biol Pharm Bull ; 42(5): 744-750, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061316

RESUMO

Increasing evidence supports that the efflux transporters, especially P-glycoprotein (P-gp), have vital roles on drug resistance in epilepsy. Overexpression of P-gp in the brain could reduce the anti-epileptic drugs (AEDs) concentration in the epileptogenic zone, resulting in drug resistance. Studies have demonstrated that recurrent seizures induce the expression of P-gp and status epilepticus (SE) could upregulate the expression of P-gp, resulting in drug resistance. MicroRNAs (miRNAs), as endogenous regulators, represent small regulatory RNA molecules that have been shown to act as negative regulators of gene expression in different biological processes. We investigated the impact of miR-146a-5p on the expression of P-gp in status epilepticus rat model. The expression of miR-146a-5p in rat cortex and hippocampus was measured by quantitative RT-PCR at 2 weeks after induction of SE. Meanwhile, we detected the expression of P-gp in the brain of SE rats using Western blotting and immunohistochemistry. Upregulation of miR-146a-5p and overexpression of P-gp were evident at 2 weeks after SE. Moreover, the expression of P-gp was downregulated by injection of miR-146a mimic into the hippocampus. We also detected the expression of interleukin-1 receptor-associated protein kinases-1 (IRAK1) and tumor necrosis factor receptor-associated factor 6 (TRAF6) and nuclear factor-kappaB (NF-κB) p65 using Western blotting and immunohistochemistry, which indicated the expression of IRAK1, TRAF6 and NF-κB p-p65/p65 increased in the brain of SE rats, and overexpression of miR-146a-5p could downregulate the expression of IRAK1, TRAF6, NF-κB p-p65/p65 and P-gp. Our study indicated that miR-146a-5p may decrease the expression of P-gp in status epilepticus rats via NF-κB signaling pathway.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Córtex Cerebral/metabolismo , Hipocampo/metabolismo , MicroRNAs , Estado Epiléptico/metabolismo , Animais , Regulação para Baixo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Cloreto de Lítio , Masculino , Pilocarpina , Ratos Sprague-Dawley , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/genética , Fator 6 Associado a Receptor de TNF/metabolismo , Fator de Transcrição RelA/metabolismo
12.
PLoS Genet ; 15(4): e1008043, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30973874

RESUMO

Mounting evidence supports that LINE-1 (L1) retrotransposition can occur postzygotically in healthy and diseased human tissues, contributing to genomic mosaicism in the brain and other somatic tissues of an individual. However, the genomic distribution of somatic human-specific LINE-1 (L1Hs) insertions and their potential impact on carrier cells remain unclear. Here, using a PCR-based targeted bulk sequencing approach, we profiled 9,181 somatic insertions from 20 postmortem tissues from five Rett patients and their matched healthy controls. We identified and validated somatic L1Hs insertions in both cortical neurons and non-brain tissues. In Rett patients, somatic insertions were significantly depleted in exons-mainly contributed by long genes-than healthy controls, implying that cells carrying MECP2 mutations might be defenseless against a second exonic L1Hs insertion. We observed a significant increase of somatic L1Hs insertions in the brain compared with non-brain tissues from the same individual. Compared to germline insertions, somatic insertions were less sense-depleted to transcripts, indicating that they underwent weaker selective pressure on the orientation of insertion. Our observations demonstrate that somatic L1Hs insertions contribute to genomic diversity and MeCP2 dysfunction alters their genomic patterns in Rett patients.


Assuntos
Elementos Nucleotídeos Longos e Dispersos , Síndrome de Rett/genética , Adolescente , Adulto , Sequência de Bases , Encéfalo/metabolismo , Estudos de Casos e Controles , Córtex Cerebral/metabolismo , Feminino , Mutação em Linhagem Germinativa , Humanos , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Mosaicismo , Mutação , Neurônios/metabolismo , Síndrome de Rett/metabolismo , Homologia de Sequência do Ácido Nucleico , Distribuição Tecidual , Transcrição Genética , Adulto Jovem
13.
Neurochem Res ; 44(6): 1387-1398, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31006092

RESUMO

The amyloid-degrading enzyme neprilysin (NEP) is one of the therapeutic targets in prevention and treatment of Alzheimer's disease (AD). As we have shown previously NEP expression in rat parietal cortex (Cx) and hippocampus (Hip) decreases with age and is also significantly reduced after prenatal hypoxia. Following the paradigms for enhancement of NEP expression and activity developed in cell culture, we analysed the efficacy of various compounds able to upregulate NEP using our model of prenatal hypoxia in rats. In addition to the previous data demonstrating that valproic acid can upregulate NEP expression both in neuroblastoma cells and in rat Cx and Hip we have further confirmed that caspase inhibitors can also restore NEP expression in rat Cx reduced after prenatal hypoxia. Here we also report that administration of a green tea catechin epigallocatechin-3-gallate (EGCG) to adult rats subjected to prenatal hypoxia increased NEP activity in blood plasma, Cx and Hip as well as improved memory performance in the 8-arm maze and novel object recognition tests. Moreover, EGCG administration led to an increased number of dendritic spines in the hippocampal CA1 area which correlated with memory enhancement. The data obtained allowed us to conclude that the decrease in the activity of the amyloid-degrading enzyme NEP, as well as a reduction in the number of labile interneuronal contacts in the hippocampus, contribute to early cognitive deficits caused by prenatal hypoxia and that there are therapeutic avenues to restore these deficits via NEP activation which could also be used for designing preventive strategies in AD.


Assuntos
Catequina/análogos & derivados , Hipóxia/tratamento farmacológico , Neprilisina/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Animais , Catequina/uso terapêutico , Linhagem Celular Tumoral , Córtex Cerebral/metabolismo , Cognição/efeitos dos fármacos , Dendritos/metabolismo , Feminino , Hipocampo/metabolismo , Humanos , Masculino , Memória/efeitos dos fármacos , Neprilisina/genética , Gravidez , Ratos Wistar , Regulação para Cima
14.
Toxicol Lett ; 311: 37-48, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31029751

RESUMO

Polybrominated diphenyl ether-153 (BDE-153) has been demonstrated to induce neuronal apoptosis in rat cerebral cortex and primary neurons, however, the roles of mitochondria and endoplasmic reticulum (ER) remain unclear in the BDE-153-induced neuronal apoptosis. To this purpose, we observed the mitochondria and ER ultrastructure changes in the neuronal apoptosis in rats following BDE-153 treatment, detected the mitochondrial membrane potential (MMP), Ca2+-Mg2+-ATP enzyme activity, and the changes of mitochondria and ER apoptosis related molecules in rat cerebral cortex and in primary neurons following BDE-153 treatment. Results showed that compared to the control group, neuronal apoptosis was significantly increased in a dose-dependent manner in rat cerebral cortex and in primary neurons following BDE-153 treatment. In comparison with control, BDE-153 treatment induced remarkable ultrastructural changes in ER rather than in mitochondria, and the severity of ER damage was worse with the increasing BDE-153 dose. Meanwhile, ER apoptosis related molecules including caspase-12 (at mRNA level), cleaved caspase-12 (at protein level), and Tmem132a (at mRNA and protein levels) were significantly increased in the cerebral cortex in rats following BDE-153 treatment, while procaspase-12 protein was significantly decreased, comparing with control. In contrast, mitochondria apoptosis related molecules (MMP, Ca2+-Mg2+-ATP enzyme activity, cyt-C protein, caspase-3, 8, 9 mRNA, caspase-8, 9 enzyme activities) did not significantly changed in the cerebral cortex of rats or in primary neurons following BDE-153 treatment, except for the elevated caspase-3 mRNA and enzyme activity. Therefore, we conclude that BDE-153 induced neuronal apoptosis was dependent on p53, and mediated more by ER than mitochondria in the cerebral cortex of rats and in primary neurons. The findings suggest that ER is a potential sensitive target of BDE-153 neurotoxicity, providing a scientific evidence for the mechanism and intervention study on PBDE's neurotoxicity.


Assuntos
Apoptose/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Retículo Endoplasmático/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Degeneração Neural , Neurônios/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Bifenil Polibromatos/toxicidade , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Células Cultivadas , Córtex Cerebral/metabolismo , Córtex Cerebral/ultraestrutura , Relação Dose-Resposta a Droga , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/ultraestrutura , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Masculino , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Neurônios/metabolismo , Neurônios/ultraestrutura , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Ratos Sprague-Dawley , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
15.
BMC Res Notes ; 12(1): 225, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30987672

RESUMO

OBJECTIVE: Delivery of constructs for silencing or over-expressing genes or their modified versions is a crucial step for studying neuronal cell biology. Therefore, efficient transfection is important for the success of these experimental techniques especially in post-mitotic cells like neurons. In this study, we have assessed the transfection rate, using a previously established protocol, in both primary cortical cultures and neuroblastoma cell lines. Transfection efficiencies in these preparations have not been systematically determined before. RESULTS: Transfection efficiencies obtained herein were (10-12%) for neuroblastoma, (5-12%) for primary astrocytes and (1.3-6%) for primary neurons. We also report on cell-type specific transfection efficiency of neurons and astrocytes within primary cortical cultures when applying cell-type selective transfection protocols. Previous estimations described in primary cortical or hippocampal cultures were either based on general observations or on data derived from unspecified number of biological and/or technical replicates. Also to the best of our knowledge, transfection efficiency of pure primary neuronal cultures or astrocytes cultured in the context of pure or mixed (neurons/astrocytes) population cultures have not been previously determined. The transfection strategy used herein represents a convenient, and a straightforward tool for targeted cell transfection that can be utilized in a variety of in vitro applications.


Assuntos
Astrócitos/metabolismo , Células-Tronco Neurais/metabolismo , Neurônios/metabolismo , Plasmídeos/metabolismo , Transfecção/métodos , Animais , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Biomarcadores/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Córtex Cerebral/citologia , Córtex Cerebral/metabolismo , Técnicas de Cocultura , Expressão Gênica , Genes Reporter , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Lipídeos/química , Lipídeos/farmacologia , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Especificidade de Órgãos , Plasmídeos/química , Cultura Primária de Células
16.
Anal Chim Acta ; 1063: 47-56, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30967185

RESUMO

We reported a novel strategy for rapidly and accurately screening biomarkers based on ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) metabolomics data. First, the preliminary variables were obtained by screening the original variables using method validation. Second, the variables were selected from the preliminary variables and formed the variable sets by testing different thresholds of single factor (variable importance in projection (VIP), fold change (FC), the area under the receiver operating characteristic curve (AUROC), and -ln(p-value)). Then the partial least squares-discriminant analysis (PLS-DA) models were performed. The best threshold of each factor, and the corresponding variable set were found by comparing the models' R2X, R2Y, and Q2. Third, the second-step-obtained variable sets were further screened by multi-factors. The best combination of the multi-factors, and the corresponding variable set were found by comparing R2X, R2Y, and Q2. The expected biomarkers were thus obtained. The proposed strategy was successfully applied to screen biomarkers in urine, plasma, hippocampus, and cortex samples of Alzheimer's disease (AD) model, and significantly decreased the time of screening and identifying biomarkers, improved the R2X, R2Y, and Q2, therefore enhanced the interpreting, grouping, and predicting abilities of the PLS-DA model compared with generally-applied procedure. This work can provide a valuable clue to scientists who search for potential biomarkers. It is expected that the developed strategy can be written as a program and applied to screen biomarkers rapidly, efficiently and accurately.


Assuntos
Doença de Alzheimer/metabolismo , Córtex Cerebral/metabolismo , Cromatografia Líquida de Alta Pressão , Hipocampo/metabolismo , Espectrometria de Massas , Metabolômica , Doença de Alzheimer/diagnóstico , Animais , Biomarcadores/análise , Biomarcadores/metabolismo , Córtex Cerebral/química , Hipocampo/química , Análise dos Mínimos Quadrados , Masculino , Ratos , Ratos Sprague-Dawley
17.
Nat Neurosci ; 22(5): 741-752, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30936556

RESUMO

Despite expanding knowledge regarding the role of astroglia in regulating neuronal function, little is known about regional or functional subgroups of brain astroglia and how they may interact with neurons. We use an astroglia-specific promoter fragment in transgenic mice to identify an anatomically defined subset of adult gray matter astroglia. Using transcriptomic and histological analyses, we generate a combinatorial profile for the in vivo identification and characterization of this astroglia subpopulation. These astroglia are enriched in mouse cortical layer V; express distinct molecular markers, including Norrin and leucine-rich repeat-containing G-protein-coupled receptor 6 (LGR6), with corresponding layer-specific neuronal ligands; are found in the human cortex; and modulate neuronal activity. Astrocytic Norrin appears to regulate dendrites and spines; its loss, as occurring in Norrie disease, contributes to cortical dendritic spine loss. These studies provide evidence that human and rodent astroglia subtypes are regionally and functionally distinct, can regulate local neuronal dendrite and synaptic spine development, and contribute to disease.


Assuntos
Astrócitos/metabolismo , Córtex Cerebral/metabolismo , Proteínas do Olho/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/metabolismo , Animais , Células Cultivadas , Espinhas Dendríticas/fisiologia , Substância Cinzenta/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Córtex Motor/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Transcriptoma
18.
PLoS Genet ; 15(4): e1008108, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31017896

RESUMO

RASopathies are a family of related syndromes caused by mutations in regulators of the RAS/Extracellular Regulated Kinase 1/2 (ERK1/2) signaling cascade that often result in neurological deficits. RASopathy mutations in upstream regulatory components, such as NF1, PTPN11/SHP2, and RAS have been well-characterized, but mutation-specific differences in the pathogenesis of nervous system abnormalities remain poorly understood, especially those involving mutations downstream of RAS. Here, we assessed cellular and behavioral phenotypes in mice expressing a Raf1L613V gain-of-function mutation associated with the RASopathy, Noonan Syndrome. We report that Raf1L613V/wt mutants do not exhibit a significantly altered number of excitatory or inhibitory neurons in the cortex. However, we observed a significant increase in the number of specific glial subtypes in the forebrain. The density of GFAP+ astrocytes was significantly increased in the adult Raf1L613V/wt cortex and hippocampus relative to controls. OLIG2+ oligodendrocyte progenitor cells were also increased in number in mutant cortices, but we detected no significant change in myelination. Behavioral analyses revealed no significant changes in voluntary locomotor activity, anxiety-like behavior, or sociability. Surprisingly, Raf1L613V/wt mice performed better than controls in select aspects of the water radial-arm maze, Morris water maze, and cued fear conditioning tasks. Overall, these data show that increased astrocyte and oligodendrocyte progenitor cell (OPC) density in the cortex coincides with enhanced cognition in Raf1L613V/wt mutants and further highlight the distinct effects of RASopathy mutations on nervous system development and function.


Assuntos
Córtex Cerebral/metabolismo , Aprendizagem , Mutação , Neuroglia/metabolismo , Síndrome de Noonan/genética , Síndrome de Noonan/psicologia , Proteínas Proto-Oncogênicas c-raf/genética , Animais , Biomarcadores , Proteína Glial Fibrilar Ácida/metabolismo , Imuno-Histoquímica , Sistema de Sinalização das MAP Quinases , Aprendizagem em Labirinto , Memória , Camundongos , Camundongos Transgênicos , Neurônios/metabolismo , Síndrome de Noonan/metabolismo , Oligodendroglia/metabolismo , Proteínas Proto-Oncogênicas c-raf/metabolismo
19.
Neurosci Biobehav Rev ; 101: 13-31, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30917923

RESUMO

The monoamine hypothesis of depression, namely that the reduction in synaptic serotonin and dopamine levels causes depression, has prevailed in past decades. However, clinical and preclinical studies have identified various cortical and subcortical regions whose altered neural activities also regulate depressive-like behaviors, independently from the monoamine system. Our systematic review indicates that neural activities of specific brain regions and associated neural circuitries are adaptively altered after chronic stress in a specific direction, such that the neural activity in the infralimbic cortex, lateral habenula and amygdala is upregulated, whereas the neural activity in the prelimbic cortex, hippocampus and monoamine systems is downregulated. The altered neural activity dynamics between monoamine systems and cortico-limbic systems are reciprocally interwoven at multiple levels. Furthermore, depressive-like behaviors can be experimentally reversed by counteracting the altered neural activity of a specific neural circuitry at multiple brain regions, suggesting the importance of the reciprocally interwoven neural networks in regulating depressive-like behaviors. These results promise for reshaping altered neural activity dynamics as a therapeutic strategy for treating depression.


Assuntos
Monoaminas Biogênicas/metabolismo , Córtex Cerebral/fisiopatologia , Depressão/metabolismo , Transtorno Depressivo/metabolismo , Sistema Límbico/fisiopatologia , Neurônios/metabolismo , Estresse Psicológico/metabolismo , Animais , Córtex Cerebral/metabolismo , Depressão/etiologia , Transtorno Depressivo/etiologia , Modelos Animais de Doenças , Humanos , Sistema Límbico/metabolismo , Vias Neurais/metabolismo , Vias Neurais/fisiopatologia , Estresse Psicológico/complicações , Área Tegmentar Ventral/metabolismo , Área Tegmentar Ventral/fisiopatologia
20.
Proc Natl Acad Sci U S A ; 116(14): 7077-7082, 2019 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-30877244

RESUMO

Extensive evidence indicates that the basolateral amygdala (BLA) interacts with other brain regions in mediating stress hormone and emotional arousal effects on memory consolidation. Brain activation studies have shown that arousing conditions lead to the activation of large-scale neural networks and several functional connections between brain regions beyond the BLA. Whether such distal interactions on memory consolidation also depend on BLA activity is not as yet known. We investigated, in male Sprague-Dawley rats, whether BLA activity enables prelimbic cortex (PrL) interactions with the anterior insular cortex (aIC) and dorsal hippocampus (dHPC) in regulating glucocorticoid effects on different components of object recognition memory. The glucocorticoid receptor (GR) agonist RU 28362 administered into the PrL, but not infralimbic cortex, immediately after object recognition training enhanced 24-hour memory of both the identity and location of the object via functional interactions with the aIC and dHPC, respectively. Importantly, posttraining inactivation of the BLA by the noradrenergic antagonist propranolol abolished the effect of GR agonist administration into the PrL on memory enhancement of both the identity and location of the object. BLA inactivation by propranolol also blocked the effect of GR agonist administration into the PrL on inducing changes in neuronal activity within the aIC and dHPC during the postlearning consolidation period as well as on structural changes in spine morphology assessed 24 hours later. These findings provide evidence that BLA noradrenergic activity enables functional interactions between the PrL and the aIC and dHPC in regulating stress hormone and emotional arousal effects on memory.


Assuntos
Androstanóis/farmacologia , Complexo Nuclear Basolateral da Amígdala/metabolismo , Córtex Cerebral/metabolismo , Glucocorticoides/metabolismo , Memória/efeitos dos fármacos , Rede Nervosa/metabolismo , Receptores de Glucocorticoides/agonistas , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/metabolismo
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