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1.
Life (Basel) ; 14(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38541637

RESUMO

The intricate relationship between alcohol consumption and intracerebral hemorrhage (ICH) presents a nuanced field of study, especially concerning the dose-dependent impact on secondary brain injury (SBI). Recognizing the established risks associated with heavy drinking, this review delves deeper into the less understood territories of low to moderate alcohol consumption. By systematically analyzing recent studies, we uncover critical insights into how varying alcohol intake levels modulate ICH risk through mechanisms such as microglial activation, oxidative stress, and the protective potential of polyphenols. This analysis extends beyond the hypertensive effects of heavy alcohol use to explore the complex molecular pathophysiology involved in alcohol-related ICH. Our findings indicate that while heavy alcohol use unequivocally exacerbates ICH risk, moderate consumption and its associated polyphenols may offer neuroprotective effects against SBI, albeit within a finely balanced threshold. This review highlights the significant gaps in current understanding and underscores the urgent need for targeted research to elucidate these complex interactions. Through this comprehensive examination, we aim to inform more nuanced public health policies and intervention strategies, taking into account the diverse effects of alcohol consumption on ICH risk.

2.
Acta Neuropathol Commun ; 12(1): 10, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229173

RESUMO

Mesencephalic astrocyte-derived neurotrophic factor (MANF) has cytoprotective effects on various injuries, including cerebral ischemia, and it can promote recovery even when delivered intracranially several days after ischemic stroke. In the uninjured rodent brain, MANF protein is expressed almost exclusively in neurons, but post-ischemic MANF expression has not been characterized. We aimed to investigate how endogenous cerebral MANF protein expression evolves in infarcted human brains and rodent ischemic stroke models. During infarct progression, the cerebral MANF expression pattern both in human and rat brains shifted drastically from neurons to expression in inflammatory cells. Intense MANF immunoreactivity took place in phagocytic microglia/macrophages in the ischemic territory, peaking at two weeks post-stroke in human and one-week post-stroke in rat ischemic cortex. Using double immunofluorescence and mice lacking MANF gene and protein from neuronal stem cells, neurons, astrocytes, and oligodendrocytes, we verified that MANF expression was induced in microglia/macrophage cells in the ischemic hemisphere. Embarking on the drastic expression transition towards inflammatory cells and the impact of blood-borne inflammation in stroke, we hypothesized that exogenously delivered MANF protein can modulate tissue recovery processes. In an attempt to enhance recovery, we designed a set of proof-of-concept studies using systemic delivery of recombinant MANF in a rat model of cortical ischemic stroke. Intranasal recombinant MANF treatment decreased infarct volume and reduced the severity of neurological deficits. Intravenous recombinant MANF treatment decreased the levels of pro-inflammatory cytokines and increased the levels of anti-inflammatory cytokine IL-10 in the infarcted cortex one-day post-stroke. In conclusion, MANF protein expression is induced in activated microglia/macrophage cells in infarcted human and rodent brains, and this could implicate MANF's involvement in the regulation of post-stroke inflammation in patients and experimental animals. Moreover, systemic delivery of recombinant MANF shows promising immunomodulatory effects and therapeutic potential in experimental ischemic stroke.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Ratos , Camundongos , Animais , AVC Isquêmico/metabolismo , Ratos Sprague-Dawley , Encéfalo/metabolismo , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , Fatores de Crescimento Neural/uso terapêutico , Acidente Vascular Cerebral/metabolismo , Infarto Cerebral/metabolismo , Inflamação/metabolismo
3.
Tzu Chi Med J ; 35(1): 1-10, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36866349

RESUMO

Intracerebral hemorrhage (ICH) is the most lethal type of cerebral stroke without effective therapy. Although clinical trials with various surgeries have been conducted, none have improved clinical outcomes compared to the current medical management for ICH. Several ICH animal models, including autologous blood injection, collagenase injection, thrombin injection, and microballoon inflation methods, have been developed to elucidate the underlying mechanisms of ICH-induced brain injury. These models could also be used for discovering new therapy for ICH preclinically. We summarize the existing ICH animal models and the evaluation parameters used to measure the disease outcomes. We conclude that these models, resembling the different aspects of ICH pathogenesis, have their advantages and disadvantages. None of the current models closely represent the severity of ICH seen in clinical settings. More appropriate models are needed to streamline ICH's clinical outcomes and be used for validating newly developed treatment protocols.

4.
Cell Death Dis ; 14(2): 128, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792604

RESUMO

During intracerebral hemorrhage (ICH), hematoma formation at the site of blood vessel damage results in local mechanical injury. Subsequently, erythrocytes lyse to release hemoglobin and heme, which act as neurotoxins and induce inflammation and secondary brain injury, resulting in severe neurological deficits. Accelerating hematoma resorption and mitigating hematoma-induced brain edema by modulating immune cells has potential as a novel therapeutic strategy for functional recovery after ICH. Here, we show that intracerebroventricular administration of recombinant human cerebral dopamine neurotrophic factor (rhCDNF) accelerates hemorrhagic lesion resolution, reduces peri-focal edema, and improves neurological outcomes in an animal model of collagenase-induced ICH. We demonstrate that CDNF acts on microglia/macrophages in the hemorrhagic striatum by promoting scavenger receptor expression, enhancing erythrophagocytosis and increasing anti-inflammatory mediators while suppressing the production of pro-inflammatory cytokines. Administration of rhCDNF results in upregulation of the Nrf2-HO-1 pathway, but alleviation of oxidative stress and unfolded protein responses in the perihematomal area. Finally, we demonstrate that intravenous delivery of rhCDNF has beneficial effects in an animal model of ICH and that systemic application promotes scavenging by the brain's myeloid cells for the treatment of ICH.


Assuntos
Edema Encefálico , Lesões Encefálicas , Animais , Humanos , Hemorragia Cerebral/complicações , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/patologia , Inflamação/complicações , Hematoma/tratamento farmacológico , Hematoma/complicações , Hematoma/metabolismo , Imunidade Inata , Modelos Animais de Doenças , Edema Encefálico/complicações , Fatores de Crescimento Neural/uso terapêutico
5.
Front Cell Neurosci ; 16: 900725, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783104

RESUMO

Stroke is a devastating medical condition with no treatment to hasten recovery. Its abrupt nature results in cataclysmic changes in the affected tissues. Resident cells fail to cope with the cellular stress resulting in massive cell death, which cannot be endogenously repaired. A potential strategy to improve stroke outcomes is to boost endogenous pro-survival pathways. The unfolded protein response (UPR), an evolutionarily conserved stress response, provides a promising opportunity to ameliorate the survival of stressed cells. Recent studies from us and others have pointed toward mesencephalic astrocyte-derived neurotrophic factor (MANF) being a UPR responsive gene with an active role in maintaining proteostasis. Its pro-survival effects have been demonstrated in several disease models such as diabetes, neurodegeneration, and stroke. MANF has an ER-signal peptide and an ER-retention signal; it is secreted by ER calcium depletion and exits cells upon cell death. Although its functions remain elusive, conducted experiments suggest that the endogenous MANF in the ER lumen and exogenously administered MANF protein have different mechanisms of action. Here, we will revisit recent and older bodies of literature aiming to delineate the expression profile of MANF. We will focus on its neuroprotective roles in regulating neurogenesis and inflammation upon post-stroke administration. At the same time, we will investigate commonalities and differences with another UPR responsive gene, X-box binding protein 1 (XBP1), which has recently been associated with MANF's function. This will be the first systematic comparison of these two UPR responsive genes aiming at revealing previously uncovered associations between them. Overall, understanding the mode of action of these UPR responsive genes could provide novel approaches to promote cell survival.

6.
Front Mol Neurosci ; 14: 682775, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34248500

RESUMO

Intracerebral hemorrhage (ICH) is a life-threatening type of stroke that disrupts the normal neurological function of the brain. Clinical studies have reported a non-linear J-shaped association between alcohol consumption levels and the occurrence of cerebral stroke. Specifically, alcohol intoxication increases stroke incidence, while moderate alcohol pre-conditioning decreases stroke frequency and improves outcomes. Although alcohol pre-consumption is likely a crucial player in ICH, the underlying mechanism remains unclear. We performed 1-h alcohol pre-conditioning followed by ICH induction in Sprague-Dawley (SD) rats to investigate the role of alcohol pre-conditioning in ICH. Interestingly, behavioral test analysis found that ethanol intoxication (3 g/kg) aggravated ICH-induced neurological deficits, but moderate ethanol pre-conditioning (0.75 g/kg) ameliorated ICH-induced neurological deficits by reducing the oxidative stress and proinflammatory cytokines release. Moreover, we found that moderate ethanol pretreatment improved the striatal endoplasmic reticulum (ER) homeostasis by increasing the chaperone protein expression and reducing oxidative stress and apoptosis caused by ICH. Our findings show that the mechanism regulated by moderate ethanol pre-conditioning might be beneficial for ICH, indicating the importance of ER homeostasis, oxidative stress, and differential cytokines release in ICH.

7.
Cells ; 9(3)2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204394

RESUMO

The endoplasmic reticulum (ER) is an intracellular organelle that performs multiple functions, such as lipid biosynthesis, protein folding, and maintaining intracellular calcium homeostasis. Thus, conditions wherein the ER is unable to fold proteins is defined as ER stress, and an inbuilt quality control mechanism, called the unfolded protein response (UPR), is activated during ER stress, which serves as a recovery system that inhibits protein synthesis. Further, based on the severity of ER stress, the response could involve both proapoptotic and antiapoptotic phases. Intracerebral hemorrhage (ICH) is the second most common subtype of cerebral stroke and many lines of evidence have suggested a role for the ER in major neurological disorders. The injury mechanism during ICH includes hematoma formation, which in turn leads to inflammation, elevated intracranial pressure, and edema. A proper understanding of the injury mechanism(s) is required to effectively treat ICH and closing the gap between our current understanding of ER stress mechanisms and ICH injury can lead to valuable advances in the clinical management of ICH.


Assuntos
Hemorragia Cerebral/patologia , Estresse do Retículo Endoplasmático , Animais , Morte Celular , Hemorragia Cerebral/terapia , Humanos , Modelos Biológicos , Transdução de Sinais
8.
Biomolecules ; 10(1)2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31935997

RESUMO

Intracerebral hemorrhage (ICH) causes an accumulation of blood in the brain parenchyma that disrupts the normal neurological function of the brain. Despite extensive clinical trials, no medical or surgical therapy has shown to be effective in managing ICH, resulting in a poor prognosis for the patients. Urocortin (UCN) is a 40-amino-acid endogenous neuropeptide that belongs to the corticotropin-releasing hormone (CRH) family. The effect of UCN is activated by binding to two G-protein coupled receptors, CRH-R1 and CRH-R2, which are expressed in brain neurons and glial cells in various brain regions. Current research has shown that UCN exerts neuroprotective effects in ICH models via anti-inflammatory effects, which generally reduced brain edema and reduced blood-brain barrier disruption. These effects gradually help in the improvement of the neurological outcome, and thus, UCN may be a potential therapeutic target in the treatment of ICH. This review summarizes the data published to date on the role of UCN in ICH and the possible protective mechanisms underlined.


Assuntos
Hemorragia Cerebral/metabolismo , Urocortinas/metabolismo , Urocortinas/farmacologia , Animais , Encéfalo/metabolismo , Hemorragia Cerebral/fisiopatologia , Hemorragia Cerebral/terapia , Hormônio Liberador da Corticotropina/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Humanos , Fármacos Neuroprotetores/farmacologia , Urocortinas/fisiologia
9.
Cells ; 8(11)2019 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-31717886

RESUMO

BACKGROUND: Neuroinflammation is a hallmark in intracerebral hemorrhage (ICH) that induces secondary brain injury, leading to neuronal cell death. ER stress-triggered apoptosis and proteostasis disruption caused neuroinflammation to play an important role in various neurological disorders. The consequences of ER stress and proteostasis disruption have rarely been studied during the course of ICH development. METHODS: ICH was induced by collagenase VII-S intrastriatal infusion. Animals were sacrificed at 0, 3, 6, 24, and 72 h post-ICH. Rats were determined for body weight changes, hematoma volume, and neurological deficits. Brain tissues were harvested for molecular signaling analysis either for ELISA, immunoblotting, immunoprecipitation, RT-qPCR, protein aggregation, or for histological examination. A non-selective proteasome inhibitor, MG132, was administered into the right striatum three hours prior to ICH induction. RESULTS: ICH-induced acute proteasome over-activation caused the early degradation of the endoplasmic reticulum (ER) chaperone GRP78 and IκB protein. These exacerbations were accompanied by the elevation of pro-apoptotic CCAAT-enhancer-binding protein homologous protein (CHOP) and pro-inflammatory cytokines expression via nuclear factor-kappa B (NF-κB) signal activation. Pre-treatment with proteasome inhibitor MG132 significantly ameliorated the ICH-induced ER stress/proteostasis disruption, pro-inflammatory cytokines, neuronal cells apoptosis, and neurological deficits. CONCLUSIONS: ICH induced rapid proteasome over-activation, leading to an exaggeration of the ER stress/proteostasis disruption, and neuroinflammation might be a critical event in acute ICH pathology.


Assuntos
Hemorragia Cerebral/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Apoptose , Hemorragia Cerebral/fisiopatologia , Citocinas , Modelos Animais de Doenças , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Inflamação/patologia , Leupeptinas/farmacologia , Masculino , NF-kappa B/metabolismo , Neuroimunomodulação/fisiologia , Complexo de Endopeptidases do Proteassoma/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
10.
Cell Transplant ; 28(9-10): 1127-1131, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31271057

RESUMO

Drug and alcohol addiction has become an emerging public health issue and is a great burden to patients, their families, and society. It is characterized by high relapse rates and significant morbidity and mortality, and most available treatments result in only modest improvement. These findings highlight the necessity for new approaches to treat addiction. Scientific reports in the past two decades suggest that addiction involves impaired neural plasticity and decreased hippocampal neurogenesis. Stem cell therapy and its derived neurotrophic factors can potentially target the underlying pathophysiology of addiction. Stem cell applications are showing promise in several preclinical studies and may provide new and noninvasive treatment strategies. Future clinical research is warranted to investigate whether stem cell-based therapy could support the treatment of addiction.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Hipocampo , Neurogênese , Plasticidade Neuronal , Células-Tronco , Transtornos Relacionados ao Uso de Substâncias , Animais , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Células-Tronco/metabolismo , Células-Tronco/patologia , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Transtornos Relacionados ao Uso de Substâncias/patologia , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Transtornos Relacionados ao Uso de Substâncias/terapia
11.
J Stroke Cerebrovasc Dis ; 27(12): 3493-3502, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30205999

RESUMO

BACKGROUND: Alcoholism is one of the risk factors for cerebrovascular diseases. Our previous study demonstrated that acute alcohol intoxication enhances brain injury and neurological impairment in rats suffering from intracerebral hemorrhage (ICH). We plan to investigate the effect of chronic alcohol consumption (CAC) in rats with ICH by magnetic resonance imaging (MRI). METHODS: Sixteen Sprague-Dawley male rats were divided into 2 groups: CAC group (fed with 10% alcohol drinking water for 4 weeks, n = 8), and Control group (plain drinking water, n = 8). ICH was induced by collagenase infusion into the right striata of all rats. Coronal T1-weighted imaging, T2-weighted imaging, T2*-weighted imaging, and diffusion-weighted imaging were generated with a 3.0T MRI scanner to investigate the changes of hemorrhagic volume and edema throughout the injury and recovery stages of ICH in rats. RESULTS: T2-weighted imaging is ideal for monitoring hematoma volume in rats. The hematoma volume was larger in the CAC group than in the control group (P < .001), however, did not correlate to post-ICH progressive edema formation (P > .7), and neurological impairment (P > .28) between the 2 groups, respectively. DISCUSSION: Although our findings indicate that CAC induces larger hematoma in rats with ICH, the underlying mechanism should be studied in the future.


Assuntos
Alcoolismo/complicações , Alcoolismo/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/etiologia , Imageamento por Ressonância Magnética , Consumo de Bebidas Alcoólicas , Animais , Encéfalo/efeitos dos fármacos , Edema Encefálico/diagnóstico por imagem , Edema Encefálico/etiologia , Modelos Animais de Doenças , Imageamento por Ressonância Magnética/métodos , Masculino , Distribuição Aleatória , Ratos Sprague-Dawley
12.
Ci Ji Yi Xue Za Zhi ; 30(1): 5-9, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29643709

RESUMO

OBJECTIVE: Spontaneous intracerebral hemorrhage (ICH) accounts for 10%-15% of all strokes and causes high mortality and morbidity. In the previous study, we demonstrated that ethanol could aggravate the severity of brain injury after ICH by increasing neuroinflammation and oxidative stress. In this study, we further investigate the acute effects of ethanol on brain injury within 24 h after ICH. MATERIALS AND METHODS: Totally, 66 male Sprague-Dawley rats were assigned randomly into two groups: saline pretreatment before ICH (saline + ICH), and ethanol pretreatment before ICH (ethanol + ICH). Normal saline (10 mL/kg) or ethanol (3 g/kg, in 10 mL/kg normal saline) was administered intraperitoneally 1 h before induction of experimental ICH. Bacterial collagenase VII-S (0.23 U in 1.0 µL sterile saline) was injected into the right striatum to induce ICH in the rats. We evaluated the hematoma expansion, hemodynamic parameters (heart rate and blood pressure), activated partial thromboplastin time (aPTT), prothrombin time (PT), and striatal matrix metallopeptidase 9 (MMP-9) expressions at 3, 6, 9, and 24 h after ICH. RESULTS: The ethanol + ICH group exhibited decreased hematoma at 3 h after ICH; nevertheless, there was a larger hematoma compared with the saline + ICH group at 9 and 24 h after ICH. The ethanol + ICH group had lower blood pressure at 3, 6, and 9 h post-ICH, but both groups maintained similar heart rates after ICH. There was no significant difference in the aPTT and PT between the two groups. Incremental ethanol concentrations had no influence on collagenase VII-S activity at 120 min in vitro. MMP-9 expression was upregulated in the right striata of the ethanol + ICH group, especially at 3 and 9 h after ICH. CONCLUSION: Ethanol delayed hematoma formation in the first 3 h due to a hypotensive effect; however, the accelerated growth of hematomas after 9 h may be a sequela of ethanol-induced MMP-9 activation.

13.
Chin J Physiol ; 60(5): 259-266, 2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-28950689

RESUMO

Basal ganglia hemorrhage accounts for approximately 50% of all hemorrhagic strokes. A good rat model that produces severe intrastriatal hemorrhage (ISH) mimicking human severe ISH is lacking. The present study compared the intra-striatal injection of 0.2 U with that of 0.6 U of collagenase in inducing severe ISH in rats. Three-Tesla (3T) magnetic resonance imaging (MRI) was used to evaluate brain injuries in terms of hematoma size (volume), midline shift (MLS), and brain edema. This evaluation was further substantiated by determination of behavior and neurologic functions and mortality over 56 h. The 0.2 U collagenase caused hematoma volume increases for 10.3 to 30.1 mm³, while the 0.6 U caused 36.4 to 114.8 mm³, at post-ISH 1 h to 56 h. The 0.6 U collagenase significantly increased MLS to 1.5-3.0 times greater than the 0.2 U did at all post-intracerebral hemorrhage (ICH) time points. The MLS increased dependently with hematoma expansion with high correlation coefficients, yet no mortality occurred. These two dosages, nevertheless, caused the same pattern and severity in relative apparent diffusion coefficient (rADC) changes for three regions of interest (ROIs). Both ISH models induced consistent behavior deficits. The larger dosage produced severe brain injuries as well as neurological deficits, more closely mimicking severe human ISH. Hematoma volume and MLS can be the most useful parameters for evaluating the ISH severity in the present experimental model. The larger dosage, therefore, would be useful for investigating the pathophysiology of the severer ISH in the striatum. This may be applied for evaluating potential therapeutic strategies and outcomes in the future.


Assuntos
Hemorragia Cerebral/etiologia , Colagenases/farmacologia , Corpo Estriado , Modelos Animais de Doenças , Envelhecimento , Animais , Humanos , Imageamento por Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley
14.
J Stroke Cerebrovasc Dis ; 25(1): 15-25, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26387045

RESUMO

OBJECTIVE: Alcohol intoxication is associated with worse intracerebral hemorrhage (ICH) outcome, indicating the important role of alcohol in ICH pathogenesis. We intended to investigate the effects of ethanol pretreatment on the severity of ICH-induced brain injury in rats. METHODS: At 1 hour after intraperitoneal injection of ethanol (3 g/kg), 0.2 U bacterial collagenase was infused into the striatum of male Sprague-Dawley rats to induce ICH. Accumulative mortality rate, body weight changes, and motorsensory and neurological abnormalities were evaluated. The hemorrhagic volume, hematoma expansion, and water content were measured by Drabkin's method, morphometric assay, and dry/wet method, respectively. Blood-brain barrier disruption was assessed using Evans blue assay. Oxidative stress was evaluated by the enzymatic activity of glutathione peroxidase, oxidation of hydroethidine, and the production of malondialdehyde. Cerebral blood flow perfusion volume and hypo-/hyperperfusion neuroimaging were examined by magnetic resonance imaging. RESULTS: Ethanol pretreatment aggravates the hematoma hemolysis, hemorrhagic volume, hematoma expansion, brain edema, blood-brain barrier disruption, microglial activation, elevated oxidative stress, and neuroinflammation in the hemorrhagic striatum. The summation effect of these consequences is the major cause of marked neurological impairment and higher mortality rate (64%) in ethanol-pretreated rats with ICH. CONCLUSION: This is a novel model to evaluate the effects of high-dose alcohol administration on experimental ICH rats. IMPLICATIONS: The present study may provide clues for making novel strategies in the management of patients with ICH who overconsume alcoholic drinks before the attack.


Assuntos
Intoxicação Alcoólica/complicações , Dano Encefálico Crônico/etiologia , Hemorragia Cerebral/complicações , Corpo Estriado/patologia , Intoxicação Alcoólica/fisiopatologia , Animais , Barreira Hematoencefálica , Dano Encefálico Crônico/patologia , Edema Encefálico/etiologia , Hemorragia Cerebral/fisiopatologia , Circulação Cerebrovascular , Modelos Animais de Doenças , Etanol/administração & dosagem , Etanol/toxicidade , Hematoma/etiologia , Inflamação , Injeções Intraperitoneais , Imageamento por Ressonância Magnética , Masculino , Microglia/patologia , Estresse Oxidativo , Imagem de Perfusão , Pré-Medicação , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Teste de Desempenho do Rota-Rod
15.
ScientificWorldJournal ; 2015: 657932, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26146654

RESUMO

Granulocyte-colony stimulating factor (G-CSF) protects brain from ischemic/reperfusion (I/R) injury, and inhibition of nitric oxide (NO) synthases partially reduces G-CSF protection. We thus further investigated the effects of G-CSF on ischemia-induced NO production and its consequence on regional cerebral blood flow (rCBF) and neurological deficit. Endothelin-1 (ET-1) microinfused above middle cerebral artery caused a rapid reduction of rCBF (ischemia) which lasted for 30 minutes and was followed by a gradual recovery of blood flow (reperfusion) within the striatal region. Regional NO concentration increased rapidly (NO surge) during ischemia and recovered soon to the baseline. G-CSF increased rCBF resulting in shorter ischemic duration and an earlier onset of reperfusion. The enhancement of the ischemia-induced NO by G-CSF accompanied by elevation of phospho-Akt and phospho-eNOS was noted, suggesting an activation of Akt/eNOS. I/R-induced infarct volume and neurological deficits were also reduced by G-CSF treatment. Inhibition of NO synthesis by L-N(G)-Nitroarginine Methyl Ester (L-NAME) significantly reduced the effects of G-CSF on rCBF, NO surge, infarct volume, and neurological deficits. We conclude that G-CSF increases rCBF through a NO surge mediated by Akt/eNOS, which partially contributes to the beneficial effect of G-CSF on brain I/R injury.


Assuntos
Isquemia Encefálica/metabolismo , Circulação Cerebrovascular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Fármacos Neuroprotetores/farmacologia , Ratos , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia
16.
Neuropeptides ; 52: 89-96, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26055808

RESUMO

Urocortin exerts neuroprotective effects in intracerebral hemorrhage (ICH) of rats. For pre-clinical trial, we intended to study the neuroprotective efficacy of human UCN (hUCN)-1, -2 and -3 in treating ICH rats. ICH was induced by infusing bacterial collagenase VII (0.23 U in sterile saline) to the striatum. The hUCN-1, -2, and -3 were administrated (2.5µg/kg, i.p.) at 1h after ICH insult, respectively. Neurological deficits were evaluated by modified Neurological Severity Scores. Brain edema and hematoma expansion was evaluated by coronal T2-WI and DWI magnetic resonance imaging on 1, 3, 6, 24, and 56h after ICH insult. Blood-brain barrier permeability was evaluated by Evans blue assay on day 3 after ICH. Brain lesion volume was evaluated by morphormetric measurement on day 7 after ICH. Our results demonstrated that the hUCN-1 significantly reduced hematoma, blood-brain barrier disruption and neurological deficits on day 3, and brain lesion volume on day 7 after ICH insult. The prediction of secondary structure of the hUCNs clarifies that the percentage of alpha-helix, random coil and extended strand between rat-UCN (rUCN)-1 and hUCN-1 are the same. The structure similarity between human- and rat-UCN-1 may be one of the reasons that both can exert similar therapeutic potential in ICH rats.


Assuntos
Hemorragia Cerebral/prevenção & controle , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/patologia , Hormônio Liberador da Corticotropina/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Urocortinas/administração & dosagem , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Hemorragia Cerebral/induzido quimicamente , Hormônio Liberador da Corticotropina/uso terapêutico , Humanos , Masculino , Colagenase Microbiana , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Sprague-Dawley , Urocortinas/uso terapêutico
17.
Stem Cells ; 33(5): 1601-17, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25641682

RESUMO

The production of midbrain dopaminergic (mDA) neurons requires precise extrinsic inductive signals and intrinsic transcriptional cascade at a specific time point in development. Urocortin (UCN) is a peptide of the corticotropin-releasing hormone family that mediates various responses to stress. UCN was first cloned from adult rat midbrain. However, the contribution of UCN to the development of mDA neurons is poorly understood. Here, we show that UCN is endogenously expressed in the developing ventral midbrain (VM) and its receptors are exhibited in Nurr1(+) postmitotic mDA precursors and TH(+) neurons, suggesting possible roles in regulating their terminal differentiation. UCN treatment increased DA cell numbers in rat VM precursor cultures by promoting the conversion of Nurr1(+) precursors into DA neurons. Furthermore, neutralization of secreted UCN with anti-UCN antibody resulted in a reduction in the number of DA neurons. UCN induced an abundance of acetylated histone H3 and enhanced late DA regulator Nurr1, Foxa2, and Pitx3 expressions. Using pharmacological and RNA interference approaches, we further demonstrated that histone deacetylase (HDAC) inhibition and late transcriptional factors upregulation contribute to UCN-mediated DA neuron differentiation. Chromatin immunoprecipitation analyses revealed that UCN promoted histone acetylation of chromatin surrounding the TH promoter by directly inhibiting HDAC and releasing of methyl CpG binding protein 2-CoREST-HDAC1 repressor complex from the promoter, ultimately leading to an increase in Nurr1/coactivators-mediated transcription of TH gene. Moreover, UCN treatment in vivo also resulted in increased DA neuron differentiation. These findings suggest that UCN might contribute to regulate late mDA neuron differentiation during VM development.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Neurônios Dopaminérgicos/citologia , Epigênese Genética/efeitos dos fármacos , Mesencéfalo/citologia , Urocortinas/farmacologia , Animais , Células Cultivadas , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Fator 3-beta Nuclear de Hepatócito/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Proteínas de Homeodomínio/metabolismo , Humanos , Mesencéfalo/embriologia , Camundongos , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , Fenótipo , Regiões Promotoras Genéticas/genética , Ratos , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Fatores de Transcrição/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Regulação para Cima/efeitos dos fármacos
18.
Cell Mol Biol Lett ; 17(3): 376-92, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22544763

RESUMO

Human adipose-derived stem cells (huADSC) were generated from fat tissue of a 65-year-old male donor. Flow cytometry and reverse transcription polymerase chain reaction (RT-PCR) analyses indicated that the huADSC express neural cell proteins (MAP2, GFAP, nestin and ß-III tubulin), neurotrophic growth factors (BDNF and GDNF), and the chemotactic factor CXCR4 and its corresponding ligand CXCL12. In addition, huADSC expressed the characteristic mesenchymal stem cell (MSC) markers CD29, CD44, CD73, CD90, CD105 and HLA class I. The huADSC were employed, via a right femoral vein injection, to treat rats inflicted with experimental intracerebral hemorrhage (ICH). Behavioral measurement on the experimental animals, seven days after the huADSC therapy, showed a significant functional improvement in the rats with stem cell therapy in comparison with rats of the control group without the stem cell therapy. The injected huADSC were detectable in the brains of the huADSC treated rats as determined by histochemistry analysis, suggesting a role of the infused huADSC in facilitating functional recovery of the experimental animals with ICH induced stroke.


Assuntos
Tecido Adiposo , Terapia Baseada em Transplante de Células e Tecidos , Hemorragia Cerebral/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Tecido Adiposo/transplante , Idoso , Animais , Terapia Baseada em Transplante de Células e Tecidos/métodos , Hemorragia Cerebral/induzido quimicamente , Colagenases/administração & dosagem , Veia Femoral , Humanos , Injeções Intravenosas , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Colagenase Microbiana , Ratos , Ratos Sprague-Dawley , Medicina Regenerativa , Acidente Vascular Cerebral/terapia
19.
J Neuroinflammation ; 9: 13, 2012 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-22257737

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) remains a serious clinical problem lacking effective treatment. Urocortin (UCN), a novel anti-inflammatory neuropeptide, protects injured cardiomyocytes and dopaminergic neurons. Our preliminary studies indicate UCN alleviates ICH-induced brain injury when administered intracerebroventricularly (ICV). The present study examines the therapeutic effect of UCN on ICH-induced neurological deficits and neuroinflammation when administered by the more convenient intraperitoneal (i.p.) route. METHODS: ICH was induced in male Sprague-Dawley rats by intrastriatal infusion of bacterial collagenase VII-S or autologous blood. UCN (2.5 or 25 µg/kg) was administered i.p. at 60 minutes post-ICH. Penetration of i.p. administered fluorescently labeled UCN into the striatum was examined by fluorescence microscopy. Neurological deficits were evaluated by modified neurological severity score (mNSS). Brain edema was assessed using the dry/wet method. Blood-brain barrier (BBB) disruption was assessed using the Evans blue assay. Hemorrhagic volume and lesion volume were assessed by Drabkin's method and morphometric assay, respectively. Pro-inflammatory cytokine (TNF-α, IL-1ß, and IL-6) expression was evaluated by enzyme-linked immunosorbent assay (ELISA). Microglial activation and neuronal loss were evaluated by immunohistochemistry. RESULTS: Administration of UCN reduced neurological deficits from 1 to 7 days post-ICH. Surprisingly, although a higher dose (25 µg/kg, i.p.) also reduced the functional deficits associated with ICH, it is significantly less effective than the lower dose (2.5 µg/kg, i.p.). Beneficial results with the low dose of UCN included a reduction in neurological deficits from 1 to 7 days post-ICH, as well as a reduction in brain edema, BBB disruption, lesion volume, microglial activation and neuronal loss 3 days post-ICH, and suppression of TNF-α, IL-1ß, and IL-6 production 1, 3 and 7 days post-ICH. CONCLUSION: Systemic post-ICH treatment with UCN reduces striatal injury and neurological deficits, likely via suppression of microglial activation and inflammatory cytokine production. The low dose of UCN necessary and the clinically amenable peripheral route make UCN a potential candidate for development into a clinical treatment regimen.


Assuntos
Hemorragia Cerebral/complicações , Encefalite/etiologia , Doenças do Sistema Nervoso/etiologia , Fármacos Neuroprotetores/administração & dosagem , Urocortinas/administração & dosagem , Análise de Variância , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Barreira Hematoaquosa/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Edema Encefálico/tratamento farmacológico , Edema Encefálico/etiologia , Antígeno CD11b/metabolismo , Contagem de Células , Hemorragia Cerebral/classificação , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/patologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ectodisplasinas/metabolismo , Injeções Intraventriculares , Fluxometria por Laser-Doppler , Masculino , Fosfopiruvato Hidratase/metabolismo , Ratos , Ratos Sprague-Dawley , Índice de Gravidade de Doença , Fatores de Tempo
20.
J Neurosurg ; 116(1): 193-200, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21981644

RESUMO

OBJECT: Intracerebral hemorrhage (ICH) accounts for about 15% of all deaths due to stroke. It frequently causes brain edema, leading to an expansion of brain volume that exerts a negative impact on ICH outcomes. The ICH-induced brain edema involves inflammatory mechanisms. The authors' in vitro study shows that urocortin (UCN) exhibits antiinflammatory and neuroprotective effects. Therefore, the neuroprotective effect of UCN on ICH in rats was investigated. METHODS: Intracerebral hemorrhage was induced by an infusion of bacteria collagenase type VII-S or autologous blood into the unilateral striatum of anesthetized rats. At 1 hour after the induction of ICH, UCN (0.05, 0.5, and 5 µg) was infused into the lateral ventricle on the ipsilateral side. The authors examined the injury area, brain water content, blood-brain barrier permeability, and neurological function. RESULTS: The UCN, administered in the ipsilateral lateral ventricle, was able to penetrate into the injured striatum. Posttreatment with UCN reduced the injury area, brain edema, and blood-brain barrier permeability and improved neurological deficits of rats with ICH. CONCLUSIONS: Posttreatment with UCN through improving neurological deficits of rats with ICH dose dependently provided a potential therapeutic agent for patients with ICH or other brain injuries.


Assuntos
Edema Encefálico/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Hemorragia Cerebral/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Urocortinas/uso terapêutico , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Encéfalo/fisiopatologia , Edema Encefálico/patologia , Edema Encefálico/fisiopatologia , Hemorragia Cerebral/patologia , Hemorragia Cerebral/fisiopatologia , Modelos Animais de Doenças , Masculino , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento , Urocortinas/farmacologia
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