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1.
Stroke ; 52(11): 3680-3691, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34694864

RESUMO

Background and Purpose: NCX3 (Na+-Ca2+ exchanger 3) plays a relevant role in stroke; indeed its pharmacological blockade or its genetic ablation exacerbates brain ischemic damage, whereas its upregulation takes part in the neuroprotection elicited by ischemic preconditioning. To identify an effective strategy to induce an overexpression of NCX3, we examined transcription factors and epigenetic mechanisms potentially involved in NCX3 gene regulation. Methods: Brain ischemia and ischemic preconditioning were induced in vitro by exposure of cortical neurons to oxygen and glucose deprivation plus reoxygenation (OGD/Reoxy) and in vivo by transient middle cerebral artery occlusion. Western blot and quantitative real-time polymerase chain reaction were used to evaluate transcripts and proteins of GATA3 (GATA-binding protein 3), KMT2A (lysine-methyltransferase-2A), and NCX3. GATA3 and KMT2A binding on NCX3 gene was evaluated by chromatin immunoprecipitation and Rechromatin immunoprecipitation experiments. Results: Among the putative transcription factors sharing a consensus sequence on the ncx3 brain promoter region, GATA3 was the only able to up-regulate ncx3. Interestingly, GATA3 physically interacted with KMT2A, and their overexpression or knocking-down increased or downregulated NCX3 mRNA and protein, respectively. Notably, site-direct mutagenesis of GATA site on ncx3 brain promoter region counteracted GATA3 and KMT2A binding on NCX3 gene. More importantly, we found that in the perischemic cortical regions of preconditioned rats GATA3 recruited KMT2A and the complex H3K4-3me (trimethylated lysine-4 of histone-3) on ncx3 brain promoter region, thus reducing transient middle cerebral artery occlusion­induced damage. Consistently, in vivo silencing of either GATA3 or KMT2A prevented NCX3 upregulation and consequently the neuroprotective effect of preconditioning stimulus. The involvement of GATA3/KMT2A complex in neuroprotection elicited by ischemic preconditioning was further confirmed by in vitro experiments in which the knocking-down of GATA3 and KMT2A reverted the neuroprotection induced by NCX3 overexpression in cortical neurons exposed to anoxic preconditioning followed by oxygen and glucose deprivation plus reoxygenation. Conclusions: Collectively, our results revealed that GATA3/KMT2A complex epigenetically activates NCX3 gene transcription during ischemic preconditioning.


Assuntos
Fator de Transcrição GATA3/metabolismo , Regulação da Expressão Gênica/fisiologia , Histona-Lisina N-Metiltransferase/metabolismo , Precondicionamento Isquêmico , Neuroproteção/fisiologia , Trocador de Sódio e Cálcio/biossíntese , Animais , Encéfalo/irrigação sanguínea , Isquemia Encefálica/metabolismo , Histonas/metabolismo , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Regulação para Cima
2.
Neurobiol Dis ; 159: 105480, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34411705

RESUMO

Imbalance in cellular ionic homeostasis is a hallmark of several neurodegenerative diseases including Amyotrophic Lateral Sclerosis (ALS). Sodium-calcium exchanger (NCX) is a membrane antiporter that, operating in a bidirectional way, couples the exchange of Ca2+ and Na + ions in neurons and glial cells, thus controlling the intracellular homeostasis of these ions. Among the three NCX genes, NCX1 and NCX2 are widely expressed within the CNS, while NCX3 is present only in skeletal muscles and at lower levels of expression in selected brain regions. ALS mice showed a reduction in the expression and activity of NCX1 and NCX2 consistent with disease progression, therefore we aimed to investigate their role in ALS pathophysiology. Notably, we demonstrated that the pharmacological activation of NCX1 and NCX2 by the prolonged treatment of SOD1G93A mice with the newly synthesized compound neurounina: (1) prevented the reduction in NCX activity observed in spinal cord; (2) preserved motor neurons survival in the ventral spinal horn of SOD1G93A mice; (3) prevented the spinal cord accumulation of misfolded SOD1; (4) reduced astroglia and microglia activation and spared the resident microglia cells in the spinal cord; (5) improved the lifespan and mitigated motor symptoms of ALS mice. The present study highlights the significant role of NCX1 and NCX2 in the pathophysiology of this neurodegenerative disorder and paves the way for the design of a new pharmacological approach for ALS.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Benzodiazepinonas/farmacologia , Neurônios Motores/efeitos dos fármacos , Doenças Neuroinflamatórias/metabolismo , Fármacos Neuroprotetores/farmacologia , Pirrolidinas/farmacologia , Trocador de Sódio e Cálcio/agonistas , Medula Espinal/efeitos dos fármacos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Astrócitos/patologia , Humanos , Camundongos , Camundongos Transgênicos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Doenças Neuroinflamatórias/patologia , Doenças Neuroinflamatórias/fisiopatologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Superóxido Dismutase/genética , Taxa de Sobrevida
3.
Mol Ther ; 28(4): 1154-1166, 2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32075715

RESUMO

Spinal muscular atrophy (SMA) is a severe neuromuscular disease affecting infants caused by alterations of the survival motor neuron gene, which results in progressive degeneration of motor neurons (MNs). Although an effective treatment for SMA patients has been recently developed, the molecular pathway involved in selective MN degeneration has not been yet elucidated. In particular, miR-206 has been demonstrated to play a relevant role in the regeneration of neuromuscular junction in several MN diseases, and particularly it is upregulated in the quadriceps, tibialis anterior, spinal cord, and serum of SMA mice. In the present paper, we demonstrated that miR-206 was transiently upregulated also in the brainstem of the mouse model of SMA, SMAΔ7, in the early phase of the disease paralleling MN degeneration and was down-regulated in the late symptomatic phase. To prevent this downregulation, we intracerebroventricularly injected miR-206 in SMA pups, demonstrating that miR-206 reduced the severity of SMA pathology, slowing down disease progression, increasing survival rate, and improving behavioral performance of mice. Interestingly, exogenous miRNA-206-induced upregulation caused a reduction of the predicted target sodium calcium exchanger isoform 2, NCX2, one of the main regulators of intracellular [Ca2+] and [Na+]. Therefore, we hypothesized that miR-206 might exert part of its neuroprotective effect modulating NCX2 expression in SMA disease.


Assuntos
Tronco Encefálico/metabolismo , MicroRNAs/genética , Trocador de Sódio e Cálcio/genética , Atrofias Musculares Espinais da Infância/terapia , Animais , Tronco Encefálico/patologia , Cálcio/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Homeostase , Humanos , Camundongos , MicroRNAs/administração & dosagem , MicroRNAs/farmacologia , Índice de Gravidade de Doença , Atrofias Musculares Espinais da Infância/genética , Atrofias Musculares Espinais da Infância/fisiopatologia , Regulação para Cima
4.
J Cereb Blood Flow Metab ; : 271678X241270284, 2024 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-39129187

RESUMO

MicroRNAs, contained in exosomes or freely circulating in the plasma, might play a pivotal role in the infarct-sparing effect exerted by remote limb ischemic postconditioning (RLIP). The aims of the present study were: (1) To evaluate the effect of pure exosomes isolated from plasma of animals subjected to RLIP systemically administered to ischemic rats; (2) To finely dissect exosomes content in terms of miRNAs; (3) To select those regulatory miRNAs specifically expressed in protective exosomes and to identify molecular pathways involved in their neurobeneficial effects. Circulating exosomes were isolated from blood of animals exposed to RLIP and administered to animals exposed to tMCAO by intracerebroventricular, intraperitoneal or intranasal routes. Exosomal miRNA signature was evaluated by microarray and FISH analysis. Plasmatic exosomes isolated from plasma of RLIP rats attenuated cerebral ischemia reperfusion injury and improved neurological functions until 3 days after ischemia induction. Interestingly, miR-702-3p and miR-423-5p seem to be mainly involved in exosome protective action by modulating NOD1 and NLRP3, two key triggers of neuroinflammation and neuronal death. Collectively, the results of the present work demonstrated that plasma-released exosomes after RLIP may transfer a neuroprotective signal to the brain of ischemic animals, thus representing a potentially translatable therapeutic strategy in stroke.

5.
J Am Heart Assoc ; 13(6): e030460, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38456444

RESUMO

BACKGROUND: REST (Repressor-Element 1 [RE1]-silencing transcription factor) inhibits Na+/Ca2+exchanger-1 (Ncx1) transcription in neurons through the binding of RE1 site on brain promoter (Br) after stroke. We identified a new putative RE1 site in Ncx1 heart promoter (Ht) sequence (Ht-RE1) that participates in neuronal Ncx1 transcription. Because REST recruits DNA-methyltransferase-1 (DNMT1) and MeCP2 (methyl-CpG binding protein 2) on different neuronal genes, we investigated the role of this complex in Ncx1 transcriptional regulation after stroke. METHODS AND RESULTS: Luciferase experiments performed in SH-SY5Y cells demonstrated that Br activity was selectively decreased by REST, whereas Ht activity was reduced by DNMT1, MeCP2, and REST. Notably, site-direct mutagenesis of Ht-RE1 prevented REST-dependent downregulation of Ncx1. Furthermore, in temporoparietal cortex of 8-week-old male wild-type mice (C57BL/6) subjected to transient middle cerebral artery occlusion, DNMT1, MeCP2, and REST binding to Ht promoter was increased, with a consequent DNA promoter hypermethylation. Intracerebroventricular injection of siREST prevented DNMT1/MeCP2 binding to Ht and Ncx1 downregulation, thus causing a reduction in stroke-induced damage. Consistently, in cortical neurons subjected to oxygen and glucose deprivation plus reoxygenation Ncx1 knockdown counteracted neuronal protection induced by the demethylating agent 5-azacytidine. For comparisons between 2 experimental groups, Student's t test was used, whereas for more than 2 experimental groups, 1-way ANOVA was used, followed by Tukey or Newman Keuls. Statistical significance was set at P<0.05. CONCLUSIONS: If the results of this study are confirmed in humans, it could be asserted that DNMT1/MeCP2/REST complex disruption could be a new pharmacological strategy to reduce DNA methylation of Ht in the brain, ameliorating stroke damage.


Assuntos
Neuroblastoma , Acidente Vascular Cerebral , Humanos , Camundongos , Masculino , Animais , Metilação de DNA , Camundongos Endogâmicos C57BL , Neuroblastoma/metabolismo , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo , Encéfalo/metabolismo , Epigênese Genética , DNA
6.
Mol Ther Nucleic Acids ; 35(1): 102131, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38379726

RESUMO

MicroRNA (miRNA), by post-transcriptionally regulating the expression of genes involved in stroke response, represents important effectors in stroke pathophysiology. Recently, the 103/107 miRNA family emerged as a possible therapeutic target in stroke, as it controls the expression of sodium calcium exchanger 1, a plasma membrane transporter that plays a fundamental role in stroke pathophysiology. Although the neuroprotective properties of this and other miRNAs are promising, several pharmacokinetic drawbacks remain to be faced for the development of a translatable therapy based on small RNAs in CNS diseases. In the present study, to overcome these limitations, the anti-miRNA103/107 was encapsulated in specific preparations of lipid nanoparticles (LNPs), and their effectiveness was evaluated both in an in vitro model of hypoxia represented by primary neuronal cortical cultures exposed to oxygen and glucose deprivation followed by reoxygenation, and in an in vivo model of stroke obtained in rats exposed to transient occlusion of the middle cerebral artery. The results of the present study demonstrated that the encapsulation of anti-miRNA103/107 in transferrin-conjugated PEG-stabilized LNPs allowed the blood-brain barrier crossing and significantly reduced brain ischemic damage. The present achievements pave the way for the exploitation of a systemic intravenous miRNA delivery strategy in stroke therapy.

7.
Biomed Pharmacother ; 167: 115503, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37729728

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive and often fatal neurodegenerative disease characterized by the loss of Motor Neurons (MNs) in spinal cord, motor cortex and brainstem. Despite significant efforts in the field, the exact pathogenetic mechanisms underlying both familial and sporadic forms of ALS have not been fully elucidated, and the therapeutic possibilities are still very limited. Here we investigate the molecular mechanisms of neurodegeneration induced by chronic exposure to the environmental cyanotoxin L-BMAA, which causes a form of ALS/Parkinson's disease (PD) in several populations consuming food and/or water containing high amounts of this compound. METHODS: In this effort, mice were chronically exposed to L-BMAA and analyzed at different time points to evaluate cellular and molecular alterations and behavioral deficits, performing MTT assay, immunoblot, immunofluorescence and immunohistochemistry analysis, and behavioral tests. RESULTS: We found that cyanotoxin L-BMAA determines apoptotic cell death and a marked astrogliosis in spinal cord and motor cortex, and induces neurotoxicity by favoring TDP-43 cytoplasmic accumulation. CONCLUSIONS: Overall, our results characterize a new versatile neurotoxic animal model of ALS that may be useful for the identification of new druggable targets to develop innovative therapeutic strategies for this disease.

8.
Int J Biol Sci ; 19(9): 2695-2710, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324938

RESUMO

Background: The inhibition of histone deacetylase 9 (HDAC9) represents a promising druggable target for stroke intervention. Indeed, HDAC9 is overexpressed in neurons after brain ischemia where exerts a neurodetrimental role. However, mechanisms of HDAC9-dependent neuronal cell death are not yet well established. Methods: Brain ischemia was obtained in vitro by primary cortical neurons exposed to glucose deprivation plus reoxygenation (OGD/Rx) and in vivo by transient middle cerebral artery occlusion. Western blot and quantitative real-time polymerase chain reaction were used to evaluate transcript and protein levels. Chromatin immunoprecipitation was used to evaluate the binding of transcription factors to the promoter of target genes. Cell viability was measured by MTT and LDH assays. Ferroptosis was evaluated by iron overload and 4-hydroxynonenal (4-HNE) release. Results: Our results showed that HDAC9 binds to hypoxia-inducible factor 1 (HIF-1) and specificity protein 1 (Sp1), two transcription activators of transferrin 1 receptor (TfR1) and glutathione peroxidase 4 (GPX4) genes, respectively, in neuronal cells exposed to OGD/Rx. Consequently, HDAC9 induced: (1) an increase in protein level of HIF-1 by deacetylation and deubiquitination, thus promoting the transcription of the pro-ferroptotic TfR1 gene; and (2) a reduction in Sp1 protein levels by deacetylation and ubiquitination, thus resulting in a down-regulation of the anti-ferroptotic GPX4 gene. Supporting these results, the silencing of HDAC9 partially prevented either HIF-1 increase and Sp1 reduction after OGD/Rx. Interestingly, silencing of the neurodetrimental factors, HDAC9, HIF-1, or TfR1 or the overexpression of the prosurvival factors Sp1 or GPX4 significantly reduced a well-known marker of ferroptosis 4-HNE after OGD/Rx. More important, in vivo, intracerebroventricular injection of siHDAC9 reduced 4-HNE levels after stroke by preventing: (1) HIF-1 and TfR1 increase and thus the augmented intracellular iron overload; and (2) a reduction of Sp1 and its target gene GPX4. Conclusions: Collectively, results obtained suggest that HDAC9 mediates post-traslational modifications of HIF-1 and Sp1 that, in turn, increases TfR1 and decreases GPX4 expression, thus promoting neuronal ferroptosis in in vitro and in vivo models of stroke.


Assuntos
Isquemia Encefálica , Sobrecarga de Ferro , Acidente Vascular Cerebral , Humanos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Fator 1 Induzível por Hipóxia , Acidente Vascular Cerebral/genética , Isquemia Encefálica/metabolismo , Morte Celular/genética , Fator de Transcrição Sp1/genética , Histona Desacetilases/genética , Proteínas Repressoras
9.
Commun Biol ; 6(1): 1155, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957344

RESUMO

Beyond motor neuron degeneration, homozygous mutations in the survival motor neuron 1 (SMN1) gene cause multiorgan and metabolic defects in patients with spinal muscular atrophy (SMA). However, the precise biochemical features of these alterations and the age of onset in the brain and peripheral organs remain unclear. Using untargeted NMR-based metabolomics in SMA mice, we identify cerebral and hepatic abnormalities related to energy homeostasis pathways and amino acid metabolism, emerging already at postnatal day 3 (P3) in the liver. Through HPLC, we find that SMN deficiency induces a drop in cerebral norepinephrine levels in overt symptomatic SMA mice at P11, affecting the mRNA and protein expression of key genes regulating monoamine metabolism, including aromatic L-amino acid decarboxylase (AADC), dopamine beta-hydroxylase (DßH) and monoamine oxidase A (MAO-A). In support of the translational value of our preclinical observations, we also discovered that SMN upregulation increases cerebrospinal fluid norepinephrine concentration in Nusinersen-treated SMA1 patients. Our findings highlight a previously unrecognized harmful influence of low SMN levels on the expression of critical enzymes involved in monoamine metabolism, suggesting that SMN-inducing therapies may modulate catecholamine neurotransmission. These results may also be relevant for setting therapeutic approaches to counteract peripheral metabolic defects in SMA.


Assuntos
Atrofia Muscular Espinal , Proteína 1 de Sobrevivência do Neurônio Motor , Animais , Humanos , Camundongos , Aminoácidos/metabolismo , Neurônios Motores/metabolismo , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/metabolismo , Neurotransmissores/metabolismo , Norepinefrina/metabolismo , Proteína 1 de Sobrevivência do Neurônio Motor/genética
10.
Biomed Pharmacother ; 154: 113587, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36029540

RESUMO

INTRODUCTION AND AIMS: The limited therapeutic options for ischemic stroke treatment render necessary the identification of new strategies. In recent years, it has been shown that natural compounds may represent a valid therapeutic opportunity. Therefore, the present study aimed to evaluate the protective effect of Ruta graveolens water extract (RGWE) in an in vivo experimental model of brain ischemia. METHODS: RGWE effects on ischemic damage and neurological function were evaluated in adult rats subjected to transient occlusion of the Middle Cerebral Artery (tMCAO), receiving two intraperitoneal injections of RGWE, 100 and 300 min after the induction of ischemia. In addition, astroglial and microglial activation was measured as GFAP and IBA-1 expression by immunofluorescence and confocal microscopy analysis. RESULTS: Treatment with RGWE containing 10 mg/kg of Rutin, the major component, ameliorates the ischemic damage and improves neurological performances. Interestingly, the pro-inflammatory states of astrocytes and microglia, respectively detected by using C3 and iNOS markers, were significantly reduced in ipsilateral cortical and striatal areas in ischemic RGWE-treated rats. CONCLUSIONS: RGWE shows a neuroprotective effect on brain infarct volume extent in a transient focal cerebral ischemia model and this effect was paralleled by the prevention of pro-inflammatory astroglial and microglial activation. Collectively, our findings support the idea that natural compounds may represent potential therapeutic opportunities against ischemic stroke.


Assuntos
Isquemia Encefálica , Ataque Isquêmico Transitório , AVC Isquêmico , Fármacos Neuroprotetores , Ruta , Animais , Encéfalo , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/complicações , Infarto da Artéria Cerebral Média/tratamento farmacológico , Isquemia , Ataque Isquêmico Transitório/complicações , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos , Água
11.
Clin Chem Lab Med ; 48(6): 757-67, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20518645

RESUMO

Muscle tissue may be damaged following intense prolonged training as a consequence of both metabolic and mechanical factors. Serum levels of skeletal muscle enzymes or proteins are markers of the functional status of muscle tissue, and vary widely in both pathological and physiological conditions. Creatine kinase, lactate dehydrogenase, aldolase, myoglobin, troponin, aspartate aminotransferase, and carbonic anhydrase CAIII are the most useful serum markers of muscle injury, but apoptosis in muscle tissues subsequent to strenuous exercise may be also triggered by increased oxidative stress. Therefore, total antioxidant status can be used to evaluate the level of stress in muscle by other markers, such as thiobarbituric acid-reactive substances, malondialdehyde, sulfhydril groups, reduced glutathione, oxidized glutathione, superoxide dismutase, catalase and others. As the various markers provide a composite picture of muscle status, we recommend using more than one to provide a better estimation of muscle stress.


Assuntos
Biomarcadores/sangue , Rabdomiólise/diagnóstico , Aldeído Liases/sangue , Aspartato Aminotransferases/sangue , Anidrase Carbônica III/sangue , Creatina Quinase/sangue , Humanos , Lactato Desidrogenases/sangue , Músculo Esquelético/lesões , Mioglobina/sangue , Estresse Oxidativo , Troponina/sangue
12.
Cell Calcium ; 87: 102195, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32240869

RESUMO

The small ubiquitin-like modifier (SUMO) conjugation (or SUMOylation) is a post-translational protein modification mechanism activated by different stress conditions that has been recently investigated in experimental models of cerebral ischemia. The expression of SUMOylation enzymes and substrates is not restricted to the nucleus, since they are present also in the cytoplasm and on plasma membrane and are involved in several physiological and pathological conditions. In the last decades, convincing evidence have supported the idea that the increased levels of SUMOylated proteins may induce tolerance to ischemic stress. In particular, it has been established that protein SUMOylation may confer neuroprotection during ischemic preconditioning. Considering the increasing evidence that SUMO can modify stability and expression of ion channels and transporters and the relevance of controlling ionic homeostasis in ischemic conditions, the present review will resume the main aspects of SUMO pathways related to the key molecules involved in maintenance of ionic homeostasis during cerebral ischemia and ischemic preconditioning, with a particular focus on the on Na+/Ca2+ exchangers.


Assuntos
Isquemia Encefálica/metabolismo , Precondicionamento Isquêmico , Trocador de Sódio e Cálcio/metabolismo , Sumoilação , Animais , Humanos , Canais Iônicos/metabolismo , Modelos Biológicos
13.
Mol Ther Nucleic Acids ; 18: 1063-1071, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31791013

RESUMO

It has been demonstrated that the K+-dependent Na+/Ca2+ exchanger, NCKX2, is a new promising stroke neuroprotective target. However, because no pharmacological activator of NCKX2 is still available, microRNA (miRNA) may represent an alternative method to modulate NCKX2 expression. In particular, by bioinformatics analysis, miR-223-5p emerged as a possible modulator of NCKX2 expression. In the light of these premises, the aims of the present study were: (1) to evaluate miR-223-5p and NCKX2 expression in the temporoparietal cortex and striatum of rats subjected to transient middle cerebral artery occlusion; (2) to evaluate whether miR-223-5p targets the 3' UTR of the NCKX2 transcript; and (3) to evaluate the effect of miR-223-5p modulation on brain ischemic volume and neurological deficits. Our results showed that miR-223-5p expression increased in a time-dependent manner in the striatum of ischemic rats in parallel with NCKX2 downregulation, and that the transfection of cortical neurons with miR-223-5p induced a reduction of NCKX2 expression. Moreover, a luciferase assay showed that miR-223-5p specifically interacts with the NCKX2 3' UTR subregion (+7037 to +8697), thus repressing NCKX2 translation. More interestingly, intracerebroventricular infusion of anti-miR-223-5p prevented NCKX2 downregulation after ischemia, thus promoting neuroprotection. The present findings support the idea that blocking miR-223-5p by antimiRNA is a reasonable strategy to reduce the neurodetrimental effect induced by NCKX2 downregulation during brain ischemia.

14.
J Sci Med Sport ; 11(6): 538-41, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17905658

RESUMO

We determined whether a short-term exhaustive dynamic exercise (cycling) for about 18min induces changes in the intramuscular architecture of the quadriceps in trained athletes. Thirty-five male athletes (age 28.8+/-9.8 years; height: 175.4.+/-5.5cm; weight: 74+/-11.5kg; average years spent training: 11.1+/-8.4 years; mean weekly duration of training: 10.4+/-3.20h) underwent an incremental cycloergometer test to exhaustion. Muscle thickness of the right quadriceps femoris (rectus femoris + vastus intermedius), and the angle of pennation of the right vastus lateralis on the quadriceps tendon were determined by high-resolution real time ultrasonography. Quadriceps thickness increased from 32.1+/-3.3mm at rest to 34.9+/-3.0mm after the test (p=0.001). The pennation angles were significantly greater after exercise (12.8+/-2.1 degrees at rest; 14.4+/-2.5 degrees after the test (p=0.001)). There are marked changes in intramuscular architecture of the quadriceps following a bout of cycloergometer exercise to exhaustion, with significant increase of quadriceps thickness and pennation angle. Ultrasonography allows to evaluate the changes of muscle architecture following exercise.


Assuntos
Ciclismo/fisiologia , Esforço Físico/fisiologia , Músculo Quadríceps/metabolismo , Adulto , Ergometria/instrumentação , Humanos , Masculino , Músculo Quadríceps/diagnóstico por imagem , Músculo Quadríceps/fisiologia , Ultrassonografia , Adulto Jovem
15.
J Neurosci Methods ; 310: 63-74, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30287283

RESUMO

BACKGROUND: In the last decades the need to find new neuroprotective targets has addressed the researchers to investigate the endogenous molecular mechanisms that brain activates when exposed to a conditioning stimulus. Indeed, conditioning is an adaptive biological process activated by those interventions able to confer resistance to a deleterious brain event through the exposure to a sub-threshold insult. Specifically, preconditioning and postconditioning are realized when the conditioning stimulus is applied before or after, respectively, the harmul ischemia. AIMS AND RESULTS: The present review will describe the most common methods to induce brain conditioning, with particular regards to surgical, physical exercise, temperature-induced and pharmacological approaches. It has been well recognized that when the subliminal stimulus is delivered after the ischemic insult, the achieved neuroprotection is comparable to that observed in models of ischemic preconditioning. In addition, subjecting the brain to both preconditioning as well as postconditioning did not cause greater protection than each treatment alone. CONCLUSIONS: The last decades have provided fascinating insights into the mechanisms and potential application of strategies to induce brain conditioning. Since the identification of intrinsic cell-survival pathways should provide more direct opportunities for translational neuroprotection trials, an accurate examination of the different models of preconditioning and postconditioning is mandatory before starting any new project.


Assuntos
Encéfalo/irrigação sanguínea , Precondicionamento Isquêmico/métodos , Animais , Humanos
16.
Neuropharmacology ; 135: 180-191, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29551690

RESUMO

Hypoxic-ischemic encephalopathy (HI) accounts for the majority of developmental, motor and cognitive deficits in children, leading to life-long neurological impairments. Since the plasmamembrane sodium/calcium exchanger (NCX) plays a fundamental role in maintaining ionic homeostasis during adult brain ischemia, in the present work we aimed to demonstrate (1)the involvement of NCX in the pathophysiology of neonatal HI and (2)a possible NCX-based pharmacological intervention. HI was induced in neonatal mice at postnatal day 7(P7) by unilateral cut of the right common carotid artery, followed by 60 min exposure to 8%O2. Expression profiles of NCX isoforms from embryos stage to adulthood was evaluated in the hippocampus of hypoxic-ischemic and control mice. To assess the effect of NCX pharmacological stimulation, brain infarct volume was evaluated in brain sections, obtained at several time intervals after systemic administration of the newly synthesized NCX activator neurounina. Moreover, the long term effect of NCX activation was evaluated in adult mice (P60) subjected to neonatal HI and daily treated with neurounina for three weeks. Hypoxic-ischemic insult induced a reduction of NCX1 and NCX3 expression starting from day 7 until day 60. Notably, 8 weeks after HI induction in P7 mice, NCX pharmacological stimulation not only reduced infarct volume but improved also motor behaviour, spatial and visual memory. The present study highlights the significant role of NCX in the evolution of neonatal brain injury and in the learning and memory processes that are impaired in mice injured in the neonatal period.


Assuntos
Benzodiazepinonas/farmacologia , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/prevenção & controle , Pirrolidinas/farmacologia , Trocador de Sódio e Cálcio/metabolismo , Animais , Animais Recém-Nascidos , Comportamento Animal/efeitos dos fármacos , Benzodiazepinonas/uso terapêutico , Encéfalo/patologia , Feminino , Hipocampo/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/patologia , Masculino , Camundongos , Isoformas de Proteínas , Pirrolidinas/uso terapêutico , Trocador de Sódio e Cálcio/biossíntese , Fatores de Tempo
17.
Front Neurosci ; 12: 510, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30131665

RESUMO

Amyotrophic lateral sclerosis (ALS) is one of the most threatening neurodegenerative disease since it causes muscular paralysis for the loss of Motor Neurons in the spinal cord, brainstem and motor cortex. Up until now, no effective pharmacological treatment is available. Two forms of ALS have been described so far: 90% of the cases presents the sporadic form (sALS) whereas the remaining 10% of the cases displays the familiar form (fALS). Approximately 20% of fALS is associated with inherited mutations in the Cu, Zn-superoxide dismutase 1 (SOD1) gene. In the last decade, ionic homeostasis dysregulation has been proposed as the main trigger of the pathological cascade that brings to motor-neurons loss. In the light of these premises, the present review will analyze the involvement in ALS pathophysiology of the most well studied metal ions, i.e., calcium, sodium, iron, copper and zinc, with particular focus to the role of ionic channels and transporters able to contribute in the regulation of ionic homeostasis, in order to propose new putative molecular targets for future therapeutic strategies to ameliorate the progression of this devastating neurodegenerative disease.

18.
PLoS One ; 13(6): e0197493, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29902182

RESUMO

Triticum vulgare has been extensively used in traditional medicine thanks to its properties of accelerating tissue repair. The specific extract of Triticum vulgare manufactured by Farmaceutici Damor (TVE-DAMOR) is already present in some pharmaceutical formulations used in the treatment of decubitus ulcers, skin lesions and burns. It has been recently suggested that this Triticum vulgare extract may possess potential anti-inflammatory properties. In the light of these premises the aim of the present paper was to verify the anti-inflammatory role of TVE, using the LPS-stimulated microglia model of inflammation. In particular the effect of different concentrations of TVE on the release of several mediators of inflammation such as nitric oxide, IL-6, PGE2 and TNF alpha was evaluated. More important, the anti-inflammatory effect of TVE was confirmed also in primary rat microglia cultures. The results of the present study show that TVE exerts anti-inflammatory properties since it reduces the release of all the evaluated markers of inflammation, such as NO, IL6, TNF alpha and PGE2 in LPS-activated BV2 microglial cells. Intriguingly, TVE reduced microglia activation and NO release also in primary microglia. Indeed, to verify the pathway of modulation of the inflammatory markers reported above, we found that TVE restores the cytoplasmic expression of p65 protein, kwown as specific marker associated with activation of inflammatory response. The evidence for an inhibitory activity on inflammation of this specific extract of Triticum vulgare may open the way to the possibility of a therapeutical use of the Triticum vulgare extract as an anti-inflammatory compound in certain pathological states such as burns, decubitus ulcers, folliculitis and inflammation of peripheral nerve.


Assuntos
Inflamação/tratamento farmacológico , Microglia/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Triticum/química , Animais , Dinoprostona/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , Interleucina-6/genética , Lipopolissacarídeos/toxicidade , Camundongos , Microglia/patologia , Óxido Nítrico/genética , Extratos Vegetais/química , Ratos , Fator de Necrose Tumoral alfa/genética , eIF-2 Quinase/genética
19.
Cell Death Dis ; 9(2): 206, 2018 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-29434186

RESUMO

Preconditioning (PC) is a phenomenon wherein a mild insult induces resistance to a later, severe injury. Although PC has been extensively studied in several neurological disorders, no studies have been performed in amyotrophic lateral sclerosis (ALS). Here we hypothesize that a sub-toxic acute exposure to the cycad neurotoxin beta-methylamino-L-alanine (L-BMAA) is able to delay ALS progression in SOD1 G93A mice and that NCX3, a membrane transporter able to handle the deregulation of ionic homeostasis occurring during ALS, takes part to this neuroprotective effect. Preconditioning effect was examined on disease onset and duration, motor functions, and motor neurons in terms of functional declines and severity of histological damage in male and female mice. Our findings demonstrate that a sub-toxic dose of L-BMAA works as preconditioning stimulus and is able to delay ALS onset and to prolong ALS mice survival. Interestingly, preconditioning prevented NCX3 downregulation in SOD1 G93A mice spinal cord, leading to an increased number of motor neurons associated to a reduced astrogliosis, and reduced the denervation of neuromuscular junctions observed in SOD1 G93A mice. These protective effects were mitigated in ncx3+/- mice. This study established for the first time an animal model of preconditioning in ALS and candidates NCX3 as a new therapeutic target.


Assuntos
Diamino Aminoácidos/farmacologia , Esclerose Lateral Amiotrófica/metabolismo , Regulação para Baixo/efeitos dos fármacos , Neurotoxinas/farmacologia , Trocador de Sódio e Cálcio/biossíntese , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/terapia , Animais , Toxinas de Cianobactérias , Camundongos , Camundongos Transgênicos , Trocador de Sódio e Cálcio/genética , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/genética , Superóxido Dismutase-1/metabolismo
20.
Int J Cardiol ; 111(1): 113-9, 2006 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-16260052

RESUMO

AIM: To study, by conventional echocardiography, left ventricular remodelling and function in master athletes, hypertension and hypertrophic cardiomyopathy. METHODS: We studied 30 master athletes (MA; soccer players; mean age 43.9+/-5.9), 24 subjects with essential hypertension (HYP; 46.6+/-6), 20 patients with hypertrophic cardiomyopathy (HCM; 42.2+/-9) and 30 normal individuals (CG; 43.4+/-5). An integrated M-mode/two-dimensional echocardiographic analysis was performed to determine chambers dimensions, relative wall thickness (RWT) and left ventricular mass (LVM), indexed to height in meters raised to the power of 2.7 (LVM/h(2.7)). Cut-off levels for LVM/h(2.7) and RWT were defined to assess 4 different patterns of LV geometric remodelling. In addition, we measured indexes of global systolic performance and indexes of global diastolic function. RESULTS: LV wall thickness and LV end-diastolic dimensions were higher in MA than controls, but significantly lower than other groups. LVH/h(2.7) was increased in 79% of HYP and in 95% of HCM, but was within the normal limits in MA. LV geometry was normal in 22 out of 30 MA (73%), while the remaining (8 athletes, 27%) showed a concentric remodelling. Systolic function (FS and EF) was normal in MA, but was slightly reduced in HYP and increased in HCM. Analysis of diastolic function showed an abnormal relaxation pattern in all HYP and 95% of HCM, but was normal in all MA. The ratio between peak filling rate and stroke volume (PFR/SV), a relatively independent index of diastolic function, was significantly greater in hypertensive patients with normal LV remodelling compared to those without it (4+/-0.39 vs. 4.91+/-0.19; P = 0.0002). CONCLUSION: MA showed lower values of wall thickness, LV dimensions and LV mass compared with HYP and HCM. Despite an abnormal remodelling, all the athletes showed a normal systolic and diastolic function. The differential diagnosis between MA, HYP and HCM is feasible by accurate, comprehensive standard Doppler echocardiography.


Assuntos
Hipertensão/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Esportes , Adulto , Humanos , Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Ultrassonografia , Remodelação Ventricular , População Branca
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