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1.
Diabetes Obes Metab ; 25(12): 3817-3825, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37735841

RESUMO

AIM: For the successful approval and clinical prescription of insulin biosimilars, it is essential to show pharmacokinetic (PK) and pharmacodynamic (PD) bioequivalence to the respective reference products sourced from the European Union and the United States. METHODS: Three phase 1, randomized, double-blind, three-period crossover trials compared single doses of the proposed biosimilar insulin analogues aspart (GL-Asp, n = 36), lispro (GL-Lis, n = 38) and glargine (GL-Gla, n = 113), all manufactured by Gan & Lee pharmaceuticals, to the respective EU- and US-reference products in healthy male participants (GL-Asp and GL-Lis) or people with type 1 diabetes (GL-Gla). Study participants received 0.2 U/kg (aspart and lispro) or 0.5 U/kg (glargine) of each treatment under automated euglycaemic clamp conditions. The clamp duration was 12 h (aspart and lispro) or 30 h (glargine). Primary PK endpoints were the total area under the PK curves (AUCins.total ) and maximum insulin concentrations (Cins.max ). Primary PD endpoints were the total area under the glucose infusion rate curve (AUCGIR.total ) and maximum glucose infusion rate (GIRmax ). RESULTS: Bioequivalence to both EU- and US-reference products were shown for all three GL insulins. Least squares mean ratios for the primary PK/PD endpoints were close to 100%, and both 90% and 95% confidence intervals were within 80%-125% in all three studies. There were no noticeable differences in the safety profiles between test and reference insulins, and no serious adverse events were reported for the GL insulins. CONCLUSION: GL-Asp, GL-Lis and GL-Gla are bioequivalent to their EU- and US-reference products.


Assuntos
Medicamentos Biossimilares , Insulina , Masculino , Humanos , Estados Unidos , Insulina Glargina/efeitos adversos , Insulina Lispro/uso terapêutico , Hipoglicemiantes/uso terapêutico , Equivalência Terapêutica , Medicamentos Biossimilares/uso terapêutico , Glicemia , Insulina Regular Humana , Estudos Cross-Over , Método Duplo-Cego , Insulina Aspart/efeitos adversos
2.
Ann Clin Transl Neurol ; 8(9): 1786-1795, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34289265

RESUMO

OBJECTIVE: JNK pathway-associated phosphatase (JKAP) is previously reported to regulate immune/inflammatory process via T-cell signaling, and closely involves in neurological diseases, while its implication in Parkinson's disease (PD) is unknown. Therefore, this study aimed to investigate the correlation of JKAP with Th1/Th2/Th17 cells and their clinical roles in PD patients, and then further explore the effect of JKAP on regulating CD4+ T-cell differentiation in PD. METHODS: Totally 50 PD patients and 50 age-/gender-matched controls were enrolled. Their blood samples were collected and proposed to ELISA and flow cytometry assays for JKAP, Th1, Th2, and Th17 measurements. In vitro, CD4+ T cells were isolated from PD patients then transfected with JKAP overexpression and knockdown Lentivirus, followed by detection of markers (CD25+ cell proportion, CD69+ cell proportion, IFN-γ, IL10, and IL17). RESULTS: JKAP was downregulated in PD patients compared to controls, which also showed good potency to discriminate them. Besides, JKAP negatively correlated with Th1 and Th17 cell proportions, but did not associate with Th2 cell proportion in PD patients; Interestingly, JKAP did not correlated with Th1, Th2, or Th17 cell proportions in controls. Furthermore, JKAP correlated with some parts of unified Parkinson's Disease Rating Scale (UPDRS) and Mini-Mental State Examination (MMSE) score. In vitro, JKAP overexpression repressed CD4+ T-cell activation and its differentiation into Th1 and Th17 cells in PD, while JKAP knockdown appeared opposite effect. INTERPRETATION: JKAP associates with disease risk and severity, correlates with Th1 and Th17 cells, and regulates CD4+ T-cell activation/differentiation in PD.


Assuntos
Fosfatases de Especificidade Dupla/sangue , Fosfatases da Proteína Quinase Ativada por Mitógeno/sangue , Doença de Parkinson/sangue , Doença de Parkinson/fisiopatologia , Células Th1 , Células Th17 , Idoso , Linfócitos T CD4-Positivos , Diferenciação Celular/fisiologia , Regulação para Baixo , Feminino , Humanos , Ativação Linfocitária/fisiologia , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Gravidade do Paciente , Risco
3.
Front Cell Neurosci ; 14: 587747, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33408612

RESUMO

This study aimed to explore the molecular regulatory network among microRNA-125b (miR-125b), forkhead box Q1 (FOXQ1), prostaglandin-endoperoxide synthase 2 (PTGS2), and cyclin-dependent kinase 5 (CDK5), as well as their effects on cell apoptosis, neurite outgrowth, and inflammation in Alzheimer disease (AD). Rat embryo cerebral cortex neurons and nerve growth factor-stimulated PC12 cells were insulted by Aß1-42 to construct two AD cellular models. Negative control (NC) inhibitor, miR-125b inhibitor, NC siRNA, FOXQ1 siRNA, PTGS2 siRNA, and CDK5 siRNA were transferred into the two AD cellular models alone or combined. Then, cell apoptosis, neurite outgrowth, proinflammatory cytokines, miR-125b, FOXQ1, PTGS2, and CDK5 expressions were detected. MiR-125b inhibition facilitated neurite outgrowth but suppressed cell apoptosis and proinflammatory cytokines (tumor necrosis factor-α, interleukin 1ß, and interleukin 6); meanwhile, it upregulated FOXQ1 but downregulated PTGS2 and CDK5. Furthermore, FOXQ1 inhibition promoted cell apoptosis and proinflammatory cytokines but repressed neurite outgrowth; PTGS2 inhibition achieved the opposite effects; CDK5 inhibition attenuated cell apoptosis, whereas it less affected neurite outgrowth and inflammation. Notably, FOXQ1 inhibition attenuated, whereas PTGS2 inhibition elevated the effect of miR-125b inhibition on regulating neurite outgrowth, cell apoptosis, and proinflammatory cytokines. As for CDK5 inhibition, it enhanced the effect of miR-125b inhibition on regulating cell apoptosis, but less impacted the neurite outgrowth and proinflammatory cytokines. Additionally, PTGS2 inhibition and CDK5 inhibition both reversed the effect of FOXQ1 inhibition on regulating cell apoptosis, neurite outgrowth, and proinflammatory cytokines. In conclusion, targeting miR-125b alleviates AD progression via blocking PTGS2 and CDK5 in a FOXQ1-dependent way.

4.
Front Aging Neurosci ; 12: 606927, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33568987

RESUMO

Neuroinflammation and inner immune dysfunction are increasingly accepted as important components of the etiopathogenesis of Parkinson's disease (PD). According to emerging evidence, a7 nicotinic acetylcholine receptor (α7nAChR), a ligand-gated ion channel, plays an important role in inflammatory reactions and is also expressed on the surface of T cells. In particular, regulatory T cells (Tregs) are critical for the maintenance of immunological tolerance. In the present study, we investigated the roles of α7nAChR in inhibiting inflammation and maintaining the immune balance in rats with 6-hydroxydopamine (6-OHDA)-induced lesions and the possible mechanisms regulating the proportion of Tregs in vivo. Adult male Wistar rats (n = 90) were subjected to a unilateral injection of 6-OHDA into the left medial forebrain bundle, and PNU-282987, an α7nAChR agonist, was intraperitoneally injected 2 h prior to the induction of lesions by 6-OHDA and again at days 1, 7, and 13 postlesion. Behavioral tests and immunohistochemical staining to detect the expression of tyrosine hydroxylase (TH) in the bilateral substantial nigra (SN) were performed. Subsequently, CD4+ T lymphocytes and the expression of forkhead/winged helix transcription factor p3 (Foxp3, which is a marker of Treg cells) in the SN were also assessed using immunofluorescence staining. The expression of glial fibrillary acidic protein (GFAP) in the SN was determined by performing immunohistochemical staining. Additionally, the protein levels of α7nAChR, extracellular signal-regulated kinase (Erk) phosphorylated-Erk (p-Erk) and Foxp3 in the ventral midbrain were determined using Western blotting, and the relative expression of the TNF-α, IL-1ß, and IL-10 mRNAs were detected using real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR). We found that PNU-282987 significantly improved the motor deficits induced by 6-OHDA, reduced the loss of TH in the SN, suppressed the overactivation of GFAP+ cells and expression of related inflammatory cytokines, and increased the number of Foxp3+ cells. In addition, we also showed that PNU-282987 significantly increased the protein expression of the a7nAchR, p-Erk, and Foxp3 in 6-OHDA-lesioned rats (p < 0.05). These results indicated that α7nAChR activation could exert an anti-inflammatory effect and participate in the process of modulating the immune balance during 6-OHDA-induced injury, potentially through the α7nAChR/p-Erk/Foxp3 signaling pathway.

5.
Neurochem Res ; 43(11): 2155-2164, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30311182

RESUMO

According to epidemiologic studies, smoking appears to downregulate the prevalence of Parkinson's disease (PD), possibly due to antiinflammatory mechanisms via activation of α7 nicotinic acetylcholine receptors (α7 nAChRs). This receptor also appears to play a role in T-cell differentiation. Recently, it has become apparent that the innate immune system participates in PD pathogenesis. The aim of this study was to evaluate the effects of auricular vagus nerve stimulation (aVNS) on substantia nigra (SN) dopaminergic neurodegeneration and the associated neuroinflammation and immune responses in a rat PD model. Adult male Wistar rats were unilaterally administered 6-hydroxydopamine (6-OHDA) to the medial forebrain bundle, followed by aVNS treatment after surgery. Following motor behavioral tests, the expression of tyrosine hydroxylase (TH) in the SN and the levels of inflammatory cytokines in the ventral midbrain were evaluated. In addition, changes in the trends of subsets of CD4+ T lymphocytes in the SN were measured by immunofluorescence staining. Western blotting was used to evaluate the α7 nAChR protein level. Compared with 6-OHDA treats rats, aVNS treatment significantly improved motor deficits, increased TH and α7 nAChR expression, and reduced the levels of inflammatory cytokines (tumor necrosis factor-a (TNF-α) and interleukin-1ß (IL-1ß)) (p < 0.05). Additionally, aVNS increased the numbers of regulatory T (Treg) cells while decreasing T helper (Th)17 cells. aVNS exerted neuroprotective effects against dopaminergic damage, possibly by suppressing the evolution of inflammation and modulating innate immune responses. Thus, aVNS may be a potential promising therapy in the future.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Oxidopamina/farmacologia , Doença de Parkinson/tratamento farmacológico , Substância Negra/efeitos dos fármacos , Nervo Vago/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Masculino , Fármacos Neuroprotetores/farmacologia , Ratos Wistar , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo , Estimulação do Nervo Vago/métodos
6.
J Int Med Res ; 46(8): 3030-3041, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30106326

RESUMO

Objective This study was performed to evaluate the potential predictors of poor outcomes associated with diabetes-specific microvascular pathologies and to analyze their influence on clinical outcomes by adjusting for other well-known prognostic factors in patients with acute ischemic stroke. Methods We analyzed 1389 consecutive adult patients with acute ischemic stroke and explored the relationship among clinical characteristics, laboratory measurements, imaging findings, and 6-month functional outcomes. Results The final study population comprised 216 patients with both acute ischemic stroke and diabetes mellitus who were followed up for 6 months. A multiple logistic regression analysis of poor outcomes revealed the following independent predictors: leukoaraiosis severity [odds ratio (OR), 7.38; 95% confidence interval (CI), 1.40-38.86, per 1-point increase), diabetic nephropathy (OR, 10.66; 95% CI, 1.10-103.43), and the admission National Institutes of Health stroke scale score (OR, 2.58; 95% CI, 1.36-4.92 per 1-point increase). In this model, admission hyperglycemia and intracerebral hemorrhagic transformation were not independent prognostic predictors. Conclusion Microvascular complications (such as nephropathy) caused by diabetes mellitus predict an unfavorable clinical outcome after acute ischemic stroke. Diabetic nephropathy may partly affect post-stroke prognosis by means of exacerbating leukoaraiosis.


Assuntos
Angiopatias Diabéticas/diagnóstico , Nefropatias Diabéticas/diagnóstico , Leucoaraiose/diagnóstico , Microvasos/fisiopatologia , Acidente Vascular Cerebral/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatologia , Estudos de Coortes , Angiopatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Feminino , Humanos , Leucoaraiose/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Recuperação de Função Fisiológica , Fatores de Risco , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento
7.
Neurol Res ; 39(1): 23-29, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27819182

RESUMO

OBJECTIVE: Cerebellar fastigial nucleus stimulation (FNS) has been shown to protect against cerebral ischemic injury. Peroxisome proliferator activator receptor gamma (PPARγ) has been reported to cause neuroprotection in animal models of stroke. The present study was performed to explore the neuroprotective mechanisms of FNS treatment in experimental stroke. METHODOLOGY: Adult male Sprague-Dawley (SD) rats preconditioned through transfection with either PPARγ-small hairpin RNA (shRNA) or lentiviral vector without shRNA and surgically subjected to middle cerebral artery occlusion and reperfusion subsequently received FNS treatment. The expression of PPARγ after FNS treatment was measured using western blotting and immunohistochemistry. Subsequently, the neuronal apoptosis, neurological deficits scores, and cerebral infarction were also evaluated. Additionally, the influence of FNS on the pro-inflammatory cytokines expression were determined by ELISA. RESULTS: We found that FNS significantly upregulated PPARγ expression, attenuated apoptosis and inflammatory response, and reduced infarct volume. The protective effect of FNS was abrogated by PPARγ-shRNA. CONCLUSION: Our results as described above suggested that FNS confers neuroprotection by upregulated PPARγ.


Assuntos
Isquemia Encefálica/complicações , Núcleos Cerebelares/fisiologia , Estimulação Elétrica , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/prevenção & controle , PPAR gama/metabolismo , Regulação para Cima/fisiologia , Análise de Variância , Animais , Apoptose/fisiologia , Isquemia Encefálica/terapia , Modelos Animais de Doenças , Encefalite/metabolismo , Ensaio de Imunoadsorção Enzimática , Marcação In Situ das Extremidades Cortadas , Infarto da Artéria Cerebral Média/complicações , Masculino , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Reperfusão , Transdução Genética
8.
Neurochem Int ; 97: 73-82, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26964767

RESUMO

Electrical stimulation of the vagus nerve, which has been used to treat epilepsy patients since 1997, also enhances long-term restoration after central nervous system (CNS) injury. Angiogenesis is a complex restorative mechanism that occurs in response to ischemic stroke, and it positively affects the recovery of neurological functions in a rat model of stroke. The aims of our study were to determine whether auricular vagus nerve stimulation (aVNS) promoted functional recovery and enhanced angiogenesis in the ischemic boundary following ischemia/reperfusion and to uncover the possible molecular mechanisms that are involved. Adult male Sprague-Dawley (SD) rats underwent transient middle cerebral artery occlusion (tMCAO) surgery and received repeated electrical stimulation of the left cavum concha starting 30 min after ischemia. For the following 21 days, we evaluated functional recovery at different time points using neurological deficit scores, the beam-walking test and the staircase test. The infarct volume was measured using TTC staining at 24 h post reperfusion, neuronal survival in the ischemic penumbra was assessed using hematoxylin and eosin (HE) staining. Microvessel density and endothelial cell proliferation in the ischemic boundary were assessed using immunofluorescence. The expression levels of brain-derived neurotrophic factor (BDNF), endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) in the ischemic penumbra were also evaluated. Our results showed that aVNS had significant neuroprotective effects and enhanced angiogenesis, which was demonstrated by improvements in the behavioral scores and brain histopathology, including increased levels of microvessel density and endothelial cell proliferation surrounding the infarct area. Furthermore, BDNF, eNOS and VEGF were expressed at higher levels in the I/R + aVNS group than in the I/R group or the I/R + sham aVNS group (p < 0.05). Our findings suggest that repeated aVNS promoted post-ischemic functional recovery and angiogenesis, possibly in conjunction with the up-regulated expression of BDNF, eNOS and VEGF in the rat brain.


Assuntos
Neovascularização Patológica/metabolismo , Neovascularização Patológica/terapia , Recuperação de Função Fisiológica/fisiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/terapia , Estimulação do Nervo Vago/métodos , Animais , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Modelos Animais de Doenças , Masculino , Neovascularização Patológica/patologia , Óxido Nítrico Sintase Tipo III/biossíntese , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Fator A de Crescimento do Endotélio Vascular/biossíntese
9.
J Neurochem ; 134(1): 173-81, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25783636

RESUMO

Vagus nerve stimulation (VNS) exerts neuroprotective effects against cerebral ischemia/reperfusion (I/R) injury and modulates redox status, potentially through the activity of miR-210, an important microRNA that is regulated by hypoxia-inducible factor and Akt-dependent pathways. The aim of this study was to determine the mechanisms of VNS- and miR-210-mediated hypoxic tolerance. Male Sprague-Dawley rats were preconditioned with a miR-210 antagomir (A) or with an antagomir control (AC), followed by middle cerebral artery occlusion and VNS treatment. The animals were divided into eight groups: sham I/R, I/R, I/R+AC, I/R+A, sham I/R+VNS, I/R+VNS, I/R+VNS+AC, and I/R+VNS+A. Activation of the endogenous cholinergic a7 nicotinic acetylcholine receptor (a7nAchR) pathway was identified using double immunofluorescence staining. miR-210 expression was measured by PCR. Behavioral outcomes, infarct volume, and neuronal apoptosis were observed at 24 h following reperfusion. Markers of oxidative stress were detected using ELISA. Rats treated with VNS showed increased miR-210 expression as well as decreased apoptosis and antioxidant stress responses compared with the I/R group; these rats also showed increased p-Akt protein expression and significantly decreased levels of cleaved caspase 3 in the ischemic penumbra, as measured by western blot and immunofluorescence analyses, respectively. Strikingly, the beneficial effects of VNS were attenuated following miR-210 knockdown. In conclusion, our results indicate that miR-210 is a potential mediator of VNS-induced neuroprotection against I/R injury. Our study highlights the neuroprotective potential of VNS, which, to date, has been largely unexplored. Since approved by the FDA in 1997, vagus nerve stimulation (VNS) has proven to be a safe and effective treatment for refractory epilepsy and resistant depression. Recent studies have found that VNS also provided neuroprotective effects against ischemic injury in a rat stroke model. We showed that miR-210 played an important role in the antioxidant stress and anti-apoptosis responses induced by VNS. This is the first report showing the effects of VNS at the mRNA level. Therefore, VNS represents a promising candidate treatment for ischemic stroke patients. Schematic view of the role of miR210 mediated in the protective effects of the VNS on the acute cerebral ischemia. VNS acts to activate neuronal and astrocytes a7nAchR , inhibits the apoptosis and oxidant stress responses possibly associated with increased Akt phosphorylation and miR210 expression.


Assuntos
Antioxidantes/metabolismo , Isquemia Encefálica/metabolismo , MicroRNAs/fisiologia , Estresse Oxidativo/fisiologia , Traumatismo por Reperfusão/metabolismo , Estimulação do Nervo Vago/métodos , Animais , Apoptose/fisiologia , Isquemia Encefálica/patologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia
10.
Int J Biol Sci ; 11(3): 353-60, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25678854

RESUMO

Apoptosis plays an essential role in ischemic stroke pathogenesis. Research on the process of neuronal apoptosis in models of ischemic brain injury seems promising. The role of growth arrest and DNA-damage-inducible protein 45 beta (Gadd45b) in brain ischemia has not been fully examined to date. This study aims to investigate the function of Gadd45b in ischemia-induced apoptosis. Adult male Sprague-Dawley rats were subjected to brain ischemia by middle cerebral artery occlusion (MCAO). RNA interference (RNAi) system, which is mediated by a lentiviral vector (LV), was stereotaxically injected into the ipsilateral lateral ventricle to knockdown Gadd45b expression. Neurologic scores and infarct volumes were assessed 24 h after reperfusion. Apoptosis-related molecules were studied using immunohistochemistry and Western blot analysis. We found that Gadd45b-RNAi significantly increased infarct volumes and worsened the outcome of transient focal cerebral ischemia. Gadd45b-RNAi also significantly increased neuronal apoptosis as indicated by increased levels of Bax and active caspase-3, and decreased levels of Bcl-2. These results indicate that Gadd45b is a beneficial mediator of neuronal apoptosis.


Assuntos
Antígenos de Diferenciação/fisiologia , Isquemia Encefálica/patologia , Neurônios/patologia , Acidente Vascular Cerebral/patologia , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Apoptose/genética , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Caspase 3/metabolismo , Regulação para Baixo , Masculino , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA , Ratos Sprague-Dawley , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/metabolismo , Proteína X Associada a bcl-2/metabolismo
11.
Med Sci Monit ; 21: 268-75, 2015 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-25619160

RESUMO

BACKGROUND: It is well known that peroxisome proliferator-activated receptor gamma (PPARγ), a ligand-activated transcription factor, plays a protective role in anti-inflammatory responses in both acute and chronic central nerve system (CNS) insults. Emerging evidence in rats suggests that vagus nerve stimulation (VNS), while restraining inflammatory cytokine production in the peripheral nervous system, also exerts a significant CNS neuroprotective function against ischemic stroke injury. The aim of this study was to explore the role of PPARγ in VNS-mediated anti-inflammatory protection against ischemic stroke damage. MATERIAL/METHODS: Adult male Sprague-Dawley rats (total n=160) preconditioned through transfection with either PPARγ small interfering RNA (siRNA) or lentiviral vector without siRNA and surgically subjected to middle cerebral artery occlusion and reperfusion subsequently received VNS treatment at 30 min post-occlusion. The expression of PPARγ after VNS treatment was measured by real-time PCR and Western blotting, also supported by immunofluorescence staining. Subsequently, the neurological deficits scores, the infarct volume, and the brain histopathology were all evaluated. Additionally, the influence on the pro-inflammatory cytokines expression and neuro-immune cells activation was determined by ELISA and immunofluorescence staining. RESULTS: We found that VNS upregulated expression of PPARγ in ischemia penumbra, diminished the extent of ischemic infarct, alleviated neuronal injury, and suppressed pro-inflammatory cytokine expression and immune cell activation (P<0.05). However, rats with PPARγ silencing failed to manifest significant neuroprotection and anti-inflammatory effect induced by VNS treatment (p>0.05). CONCLUSIONS: PPARγ may participate in the process by which VNS modulates the neuro-inflammatory response following ischemia/reperfusion in rats.


Assuntos
Isquemia Encefálica/patologia , PPAR gama/metabolismo , Traumatismo por Reperfusão/patologia , Estimulação do Nervo Vago , Nervo Vago/metabolismo , Animais , Sistema Nervoso Central/patologia , Citocinas/metabolismo , Inativação Gênica , Inflamação/patologia , Masculino , Microscopia de Fluorescência , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima
12.
Mol Neurobiol ; 52(3): 1245-1256, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25324012

RESUMO

Stroke causes devastating and irreversible losses of neurological function with subsequent slow and incomplete recovery of lost brain functions, because of the brain's limited capacity for brain plasticity. Growth arrest and DNA-damage-inducible protein 45 beta (Gadd45b) has recently been demonstrated as a candidate plasticity-related gene, making it an excellent candidate molecule that has therapeutic potential. Here, we examine whether in vivo blockage of Gadd45b affects axonal plasticity and subsequent functional recovery after focal brain infarction. Adult male Sprague-Dawley rats were subjected to cerebral ischemia by middle cerebral artery occlusion (MCAO). We adopted RNA interference (RNAi) mediated by a lentiviral vector (LV) as a means of suppressing the expression of Gadd45b. Functional recovery was assessed with a battery of tests that measured skilled forelimb reaching and forelimb balance controlling. Axonal reorganization at the level of the red nucleus was revealed by anatomical studies. Axonal regeneration was measured by elevated expression of growth-associated protein 43 (GAP-43). The levels of brain-derived neurotrophic factor (BDNF), cyclic AMP (cAMP), protein kinase A (PKA), and Rho-kinase (ROCK) were determined. Gadd45b-RNAi significantly inhibited axonal plasticity (axonal regeneration and axonal reorganization) after MCAO. This inhibition was paralleled by worse functional recovery performance on several behavioral measures. Gadd45b-RNAi also significantly decreased the expression levels of both BDNF and cAMP/PKA/phosphorylated cAMP response element-binding protein (pCREB) pathway and promoted ROCK expression. We conclude that Gadd45b stimulates recovery after stroke by enhancing axonal plasticity required for brain repair. Pharmacological targeting of Gadd45b provides new opportunities for stroke treatment.


Assuntos
Antígenos de Diferenciação/fisiologia , Infarto da Artéria Cerebral Média/fisiopatologia , Regeneração Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Antígenos de Diferenciação/genética , Axônios/fisiologia , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Regulação da Expressão Gênica , Masculino , Interferência de RNA , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Transdução de Sinais/fisiologia , Quinases Associadas a rho/biossíntese , Quinases Associadas a rho/genética
13.
PLoS One ; 9(7): e102342, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25036185

RESUMO

Inflammation and apoptosis play critical roles in the acute progression of ischemic injury pathology. Emerging evidence indicates that vagus nerve stimulation (VNS) following focal cerebral ischemia and reperfusion (I/R) may be neuroprotective by limiting infarct size. However, the underlying molecular mechanisms remain unclear. In this study, we investigated whether the protective effects of VNS in acute cerebral I/R injury were associated with anti-inflammatory and anti-apoptotic processes. Male Sprague-Dawley (SD) rats underwent VNS at 30 min after focal cerebral I/R surgery. Twenty-four h after reperfusion, neurological deficit scores, infarct volume, and neuronal apoptosis were evaluated. In addition, the levels of pro-inflammatory cytokines were detected using enzyme-linked immune sorbent assay (ELISA), and immunofluorescence staining for the endogenous "cholinergic anti-inflammatory pathway" was also performed. The protein expression of a7 nicotinic acetylcholine receptor (a7nAchR), phosphorylated Akt (p-Akt), and cleaved caspase 3 in ischemic penumbra were determined with Western blot analysis. I/R rats treated with VNS (I/R+VNS) had significantly better neurological deficit scores, reduced cerebral infarct volume, and decreased number of TdT mediated dUTP nick end labeling (TUNEL) positive cells. Furthermore, in the ischemic penumbra of the I/R+VNS group, the levels of pro-inflammatory cytokines and cleaved caspase 3 protein were significantly decreased, and the levels of a7nAchR and phosphorylated Akt were significantly increased relative to the I/R alone group. These results indicate that VNS is neuroprotective in acute cerebral I/R injury by suppressing inflammation and apoptosis via activation of cholinergic and a7nAchR/Akt pathways.


Assuntos
Acetilcolina/metabolismo , Isquemia Encefálica/complicações , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/terapia , Transdução de Sinais , Estimulação do Nervo Vago , Animais , Apoptose , Circulação Cerebrovascular , Citocinas/metabolismo , Regulação da Expressão Gênica , Masculino , Microglia/metabolismo , Neurônios/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
14.
Neurosci Lett ; 520(1): 110-4, 2012 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-22634525

RESUMO

This study focused on the effects of electrical stimulation of cerebellar fastigial nucleus on the expression of growth arrest and DNA damage inducible gene ß (Gadd45ß) and on motor function recovery after focal cerebral ischemia/reperfusion (I/R) in rats. Sprague-Dawley (SD) rats were randomly divided into 4 groups: sham I/R (control group), I/R (I/R group), I/R with sham stimulation and I/R with electrical stimulation at 6h, 12h, 24h, 2d and 3d after I/R. Cerebral ischemia and reperfusion was established by nylon monofilament occlusion method. Fastigial nucleus (FN) electrical stimulation was applied at 2h after ischemia for 1h. The changes in the expression of Gadd45ß were analyzed by immunohistochemistry, real-time polymerase chain reaction (PCR) and Western-blot respectively. Another group of rats were divided into the same 4 groups. Montoya staircase test score was used to test the motor function of affected forelimb. The levels of Gadd45ß were significantly elevated after I/R injury. FN electrical stimulation treatment elevated the expression of Gadd45ß further and improved motor function recovery. These results suggest that FN electrical stimulation can promote the expression of Gadd45ß and motor function recovery after focal cerebral ischemia.


Assuntos
Antígenos de Diferenciação/metabolismo , Isquemia Encefálica/terapia , Núcleos Cerebelares/metabolismo , Terapia por Estimulação Elétrica , Destreza Motora , Traumatismo por Reperfusão/terapia , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia
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