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1.
J Integr Neurosci ; 22(6): 168, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38176945

RESUMO

BACKGROUND: The purpose of this study was to investigate the potential involvement of pyruvate kinase M2 (PKM2), an enzyme acting as a rate-limiting enzyme in the final phase of glycolysis, in the regulation of glial activation and brain damage of intracerebral hemorrhage (ICH). METHODS: Western blotting and immunofluorescence were performed to investigate PKM2 expression, terminal deoxynucleotidyl transferase deoxyurinary triphosphate (dUTP) nick end labeling staining, hematoxylin and eosin staining, and behavioral tests were employed to evaluate the brain damage of ICH mice, and RNA-seq and bioinformatic analyses were performed to detect gene expression changes in ICH mice treated with TEPP-46. RESULTS: Increased PKM2 levels in perihematomal brain tissue were found starting from 3 days following ICH and peaked at 5 and 7 days post ICH. The increased expression of PKM2 was mainly co-localized with glial fibrillary acidic protein (GFAP)+ astrocytes and ionized calcium binding adaptor molecule-1 (IBA-1)+ microglia. Furthermore, we observed a notable increase in the nuclear translocation of PKM2 in glial cells following ICH. TEPP-46 treatment significantly reduced PKM2 nuclear translocation, and effectively attenuated glial activation and brain injury, and improved functional recovery of mice with ICH. RNA-seq data indicated that 91.1% (205/225) of differentially expressed genes (DEGs) were down-regulated in the TEPP-46 treated groups compared with the vehicle-treated groups in ICH brains. Furthermore, bioinformatic analyses revealed that these down-regulated DEGs were involved in a variety of biological processes, including autophagy and metabolic processes. In addition, the majority of these downregulated DEGs had a primary high expression in neurons, with subsequent expression seen in endothelial cells, microglia, and astrocytes. CONCLUSIONS: These results indicate that increased PKM2 nuclear translocation promotes the activation of glial cells after ICH, hence aggravating ICH-induced brain damage, and aggravates the brain injury induced by ICH. This highlights a potential therapeutic target for inhibiting glial activation to attenuate brain injury after ICH.


Assuntos
Lesões Encefálicas , Hemorragia Cerebral , Neuroglia , Piruvato Quinase , Animais , Camundongos , Lesões Encefálicas/metabolismo , Hemorragia Cerebral/metabolismo , Células Endoteliais/metabolismo , Neuroglia/metabolismo , Piruvato Quinase/metabolismo
2.
Cell Mol Neurobiol ; 42(8): 2791-2804, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34460038

RESUMO

It is unclear how Toll-like receptor (TLR) 4 signaling affects protein succinylation in the brain after intracerebral hemorrhage (ICH). Here, we constructed a mouse ICH model to investigate the changes in ICH-associated brain protein succinylation, following a treatment with a TLR4 antagonist, TAK242, using a high-resolution mass spectrometry-based, quantitative succinyllysine proteomics approach. We characterized the prevalence of approximately 6700 succinylation events and quantified approximately 3500 sites, highlighting 139 succinyllysine site changes in 40 pathways. Further analysis showed that TAK242 treatment induced an increase of 29 succinyllysine sites on 28 succinylated proteins and a reduction of 24 succinyllysine sites on 23 succinylated proteins in the ICH brains. TAK242 treatment induced both protein hypersuccinylations and hyposuccinylations, which were mainly located in the mitochondria and cytoplasm. GO analysis showed that TAK242 treatment-induced changes in the ICH-associated succinylated proteins were mostly located in synapses, membranes and vesicles, and enriched in many cellular functions/compartments, such as metabolism, synapse, and myelin. KEGG analysis showed that TAK242-induced hyposuccinylation was mainly linked to fatty acid metabolism, including elongation and degradation. Moreover, a combined analysis of the succinylproteomic data with previously published transcriptome data revealed that most of the differentially succinylated proteins induced by TAK242 treatment were mainly distributed throughout neurons, astrocytes, and endothelial cells, and the mRNAs of seven and three succinylated proteins were highly expressed in neurons and astrocytes, respectively. In conclusion, we revealed that several TLR4 signaling pathways affect the succinylation processes and pathways in mouse ICH brains, providing new insights on the ICH pathophysiological processes. Data are available via ProteomeXchange with identifier PXD025622.


Assuntos
Células Endoteliais , Receptor 4 Toll-Like , Animais , Encéfalo/metabolismo , Hemorragia Cerebral/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Ácidos Graxos , Camundongos , Sulfonamidas , Receptor 4 Toll-Like/metabolismo
3.
Cell Mol Neurobiol ; 42(6): 1897-1908, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33712886

RESUMO

Neurons in the penumbra (the area surrounding ischemic tissue that consists of still viable tissue but with reduced blood flow and oxygen transport) may be rescued following stroke if adequate perfusion is restored in time. It has been speculated that post-stroke angiogenesis in the penumbra can reduce damage caused by ischemia. However, the mechanism for neovasculature formation in the brain remains unclear and vascular-targeted therapies for brain ischemia remain suboptimal. Here, we show that VEGFR1 was highly upregulated in pericytes after stroke. Knockdown of VEGFR1 in pericytes led to increased infarct area and compromised post-ischemia vessel formation. Furthermore, in vitro studies confirmed a critical role for pericyte-derived VEGFR1 in both endothelial tube formation and pericyte migration. Interestingly, our results show that pericyte-derived VEGFR1 has opposite effects on Akt activity in endothelial cells and pericytes. Collectively, these results indicate that pericyte-specific expression of VEGFR1 modulates ischemia-induced vessel formation and vascular integrity in the brain.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Circulação Cerebrovascular/fisiologia , Células Endoteliais/metabolismo , Humanos , Isquemia/metabolismo , Perfusão , Pericitos , Acidente Vascular Cerebral/metabolismo
4.
J Immunol ; 198(2): 820-831, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27986908

RESUMO

Reducing excessive inflammation is beneficial for the recovery from intracerebral hemorrhage (ICH). Here, the roles and mechanisms of A20 (TNFAIP3), an important endogenous anti-inflammatory factor, are examined in ICH. A20 expression in the PBMCs of ICH patients and an ICH mouse model was detected, and the correlation between A20 expression and neurologic deficits was analyzed. A20 expression was increased in PBMCs and was negatively related to the modified Rankin Scale score. A20 expression was also increased in mouse perihematomal tissues. A20-/- and A20-overexpressing mice were generated to further analyze A20 function. Compared with wild-type (WT) mice, A20-/- and A20-overexpressing mice showed significant increases and decreases, respectively, in hematoma volume, neurologic deficit score, mortality, neuronal degeneration, and proinflammatory factors. Moreover, WT-A20-/- parabiosis was established to explore the role of A20 in peripheral blood in ICH injury. ICH-induced damage, including brain edema, neurologic deficit score, proinflammatory factors, and neuronal apoptosis, was reduced in A20-/- parabionts compared with A20-/- mice. Finally, the interactions between TRAF6 and Ubc13 and UbcH5c were increased in A20-/- mice compared with WT mice; the opposite occurred in A20-overexpressing mice. Enhanced IκBα degradation and NF-κB activation were observed in A20-/- mice, but the results were reversed in A20-overexpressing mice. These results suggested that A20 is involved in regulating ICH-induced inflammatory injury in both the central and peripheral system and that A20 reduces ICH-induced inflammation by regulating TRAF6 polyubiquitination. Targeting A20 may thus be a promising therapeutic strategy for ICH.


Assuntos
Hemorragia Cerebral/patologia , Inflamação/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Adulto , Idoso , Animais , Apoptose/fisiologia , Western Blotting , Hemorragia Cerebral/imunologia , Hemorragia Cerebral/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Feminino , Imunofluorescência , Técnicas de Silenciamento de Genes , Humanos , Imunoprecipitação , Inflamação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/imunologia , Ubiquitinação
5.
FASEB J ; 31(7): 2948-2962, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28386044

RESUMO

Inflammatory processes play critical roles in epileptogenesis, but the exact mechanisms that underlie these processes are still not completely understood. In this study, we investigated the role of forkhead transcription factor 3 (Foxp3), a transcription factor that is involved in T-cell differentiation, in epileptogenesis. In both human epileptic tissues and experimental seizure models, we found significant up-regulation of Foxp3 in neurons and glial cells. Of importance, Foxp3-/- mice were susceptible to kainic acid-induced seizures, whereas overexpression of Foxp3 reduced acute seizure occurrence and decreased chronic seizure recurrence. In addition, in vitro experiments revealed that Foxp3 inhibited neuronal excitability via glial cells and not neurons. The protective effects of Foxp3 were manifested as a reduction in glial cell activation and proinflammatory cytokine production and increased neuronal survival. Moreover, we showed that beneficial effects of Foxp3 involved the attenuation of TLR4 signaling and inflammation, which led to the inactivation of NR2B-containing NMDA receptors. These results suggest that Foxp3 in glial cells may play an antiepileptic role in epileptogenesis and may act as a modulator of TLR4. Taken together, our results indicate that Foxp3 may represent a novel therapeutic target for achieving anticonvulsant effects in patients with epilepsy that is currently resistant to drugs.-Wang, F.-X., Xiong, X.-Y., Zhong, Q., Meng, Z.-Y., Yang, H., Yang, Q.-W. Foxp3 exhibits antiepileptic effects in ictogenesis involved in TLR4 signaling.


Assuntos
Epilepsia/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Receptor 4 Toll-Like/metabolismo , Antagonistas Adrenérgicos alfa/farmacologia , Animais , Anticonvulsivantes/farmacologia , Células Cultivadas , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Ácido Caínico/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Neuroglia/fisiologia , Neurônios/fisiologia , Piperidinas/farmacologia , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/genética
6.
Int J Phytoremediation ; 20(5): 490-498, 2018 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-28949764

RESUMO

A bamboo species (Phyllostachys praecox) and a Cd/Zn hyperaccumulator (Sedum plumbizincicola) were tested under different planting systems to compare their heavy metal phytoremediation ability. P. praecox (MP), S. plumbizincicola (MS) and P. praecox × S. plumbizincicola (IPS) plantations were established in Cu, Zn, and Cd-contaminated soil. Soil properties and heavy metal contents in plants were determined and compared after four years of plantation establishment. The rankings of available and total metal contents in soil layers were MP > MS > IPS (0-20 cm) and MP > IPS > MS (20-40 cm, except for Cu), respectively. The Cu and Zn contents in mature bamboo tissues were significantly lower, but the Cd contents in bamboo tissues (except for leaves) higher, in the IPS than in the MP. The bioconcentration and the translocation factors in most of bamboo tissues showed an increasing trend from the MP to the IPS. Heavy metal distribution in plants is greatly affected by the planting patterns. The tested intercropping system of two plant species showed higher biomass productivity, implying more heavy metals can be removed from the soil through the harvesting of plants. Therefore, the IPS leads to significant improvement of soil phytoremediation.


Assuntos
Metais Pesados/análise , Sedum , Poluentes do Solo/análise , Biodegradação Ambiental , Cádmio , Solo
7.
Circulation ; 134(14): 1025-1038, 2016 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-27576776

RESUMO

BACKGROUND: Disturbance of brain iron metabolism after intracerebral hemorrhage (ICH) results in oxidative brain injury and cognition impairment. Hepcidin plays an important role in regulating iron metabolism, and we have reported that serum hepcidin is positively correlated with poor outcomes in patients with ICH. However, the roles of hepcidin in brain iron metabolism after ICH remain largely unknown. METHODS: Parabiosis and ICH models combined with in vivo and in vitro experiments were used to investigate the roles of hepcidin in brain iron metabolism after ICH. RESULTS: Increased hepcidin-25 was found in serum and primarily in astrocytes after ICH. The brain iron efflux, oxidative brain injury, and cognition impairment were improved in Hepc-/- ICH mice but aggravated by the human hepcidin-25 peptide in C57BL/6 ICH mice. Data obtained in in vitro studies showed that increased hepcidin inhibited the intracellular iron efflux of brain microvascular endothelial cells but was rescued by a hepcidin antagonist, fursultiamine. Using parabiosis ICH models also shows that increased serum hepcidin prevents brain iron efflux. In addition, Toll-like receptor 4 (TLR4)/MyD88 signaling pathway increased hepcidin expression by promoting interleukin-6 expression and signal transducer and activator of transcription 3 phosphorylation. TLR4-/- and MyD88-/- mice exhibited improvement in brain iron efflux at 7, 14, and 28 days after ICH, and the TLR4 antagonist (6R)-6-[N-(2-chloro-4-fluorophenyl) sulfamoyl] cyclohex-1-ene-1-carboxylate significantly decreased brain iron levels at days 14 and 28 after ICH and improved cognition impairment at day 28. CONCLUSIONS: The results presented here show that increased hepcidin expression caused by inflammation prevents brain iron efflux via inhibition of the intracellular iron efflux of brain microvascular endothelial cells entering into circulation and aggravating oxidative brain injury and cognition impairment, which identifies a mechanistic target for muting inflammation to promote brain iron efflux and to attenuate oxidative brain injury after ICH.


Assuntos
Lesões Encefálicas/metabolismo , Hemorragia Cerebral/metabolismo , Disfunção Cognitiva/metabolismo , Hepcidinas/metabolismo , Ferro/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Lesões Encefálicas/complicações , Disfunção Cognitiva/etiologia , Células Endoteliais/metabolismo , Inflamação/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 88 de Diferenciação Mieloide/genética , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/genética
8.
J Immunol ; 192(12): 5984-92, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-24808360

RESUMO

Promoting hematoma absorption is a novel therapeutic strategy for intracerebral hemorrhage (ICH); however, the mechanism of hematoma absorption is unclear. The present study explored the function and potential mechanism of CD36 in hematoma absorption using in vitro and in vivo ICH models. Hematoma absorption in CD36-deficient ICH patients was examined. Compared with patients with normal CD36 expression, CD36-deficient ICH patients had slower hematoma adsorption and aggravated neurologic deficits. CD36 expression in perihematomal tissues in wild-type mice following ICH was increased, whereas the hematoma absorption in CD36(-/-) mice was decreased. CD36(-/-) mice also showed aggravated neurologic deficits and increased TNF-α and IL-1ß expression levels. The phagocytic capacity of CD36(-/-) microglia for RBCs was also decreased. Additionally, the CD36 expression in the perihematoma area after ICH in TLR4(-/-) and MyD88(-/-) mice was significantly increased, and hematoma absorption was significantly promoted, which was significantly inhibited by an anti-CD36 Ab. In vitro, TNF-α and IL-1ß significantly inhibited the microglia expression of CD36 and reduced the microglia phagocytosis of RBCs. Finally, the TLR4 inhibitor TAK-242 upregulated CD36 expression in microglia, promoted hematoma absorption, increased catalase expression, and decreased the H2O2 content. These results suggested that CD36 mediated hematoma absorption after ICH, and TLR4 signaling inhibited CD36 expression to slow hematoma absorption. TLR4 inhibition could promote hematoma absorption and significantly improve neurologic deficits following ICH.


Assuntos
Transtornos Plaquetários/imunologia , Hemorragia Encefálica Traumática/imunologia , Antígenos CD36/imunologia , Doenças Genéticas Inatas/imunologia , Hematoma Epidural Craniano/imunologia , Proteínas do Tecido Nervoso/imunologia , Transdução de Sinais/imunologia , Receptor 4 Toll-Like/imunologia , Adulto , Idoso , Animais , Transtornos Plaquetários/genética , Transtornos Plaquetários/patologia , Hemorragia Encefálica Traumática/genética , Hemorragia Encefálica Traumática/patologia , Antígenos CD36/genética , Catalase/genética , Catalase/imunologia , Feminino , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/patologia , Hematoma Epidural Craniano/genética , Hematoma Epidural Craniano/patologia , Humanos , Peróxido de Hidrogênio/imunologia , Masculino , Camundongos Knockout , Microglia/imunologia , Microglia/patologia , Pessoa de Meia-Idade , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Proteínas do Tecido Nervoso/genética , Fagocitose/genética , Fagocitose/imunologia , Estudos Retrospectivos , Transdução de Sinais/genética , Receptor 4 Toll-Like/genética
9.
J Immunol ; 192(10): 4783-94, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24729619

RESUMO

Recent reports have shown that preconditioning with the TLR3 ligand polyinosinic-polycytidylic acid (poly(I:C)) protects against cerebral ischemia/reperfusion (I/R) injury. However, it is unclear whether poly(I:C) treatment after cerebral I/R injury is also effective. We used mouse/rat middle cerebral artery occlusion and cell oxygen-glucose deprivation models to evaluate the therapeutic effects and mechanisms of poly(I:C) treatment. Poly(I:C) was i.p. injected 3 h after ischemia (treatment group). Cerebral infarct volumes and brain edemas were significantly reduced, and neurologic scores were significantly increased. TNF-α and IL-1ß levels were markedly decreased, whereas IFN-ß levels were greatly increased, in the ischemic brain tissues, cerebral spinal fluid, and serum. Injuries to hippocampal neurons and mitochondria were greatly reduced. The numbers of TUNEL-positive and Fluoro-Jade B(+) cells also decreased significantly in the ischemic brain tissues. Poly(I:C) treatment increased the levels of Hsp27, Hsp70, and Bcl2 and decreased the level of Bax in the ischemic brain tissues. Moreover, poly(I:C) treatment attenuated the levels of TNF-α and IL-1ß in serum and cerebral spinal fluid of mice stimulated by LPS. However, the protective effects of poly(I:C) against cerebral ischemia were abolished in TLR3(-/-) and TLR4(-/-)mice. Poly(I:C) downregulated TLR4 signaling via TLR3. Poly(I:C) treatment exhibited obvious protective effects 14 d after ischemia and was also effective in the rat permanent middle cerebral artery occlusion model. The results suggest that poly(I:C) exerts therapeutic effects against cerebral I/R injury through the downregulation of TLR4 signaling via TLR3. Poly(I:C) is a promising new drug candidate for the treatment of cerebral infarcts.


Assuntos
Antivirais/farmacologia , Isquemia Encefálica/tratamento farmacológico , Regulação para Baixo/efeitos dos fármacos , Poli I-C/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Receptor 3 Toll-Like/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Isquemia Encefálica/genética , Isquemia Encefálica/imunologia , Isquemia Encefálica/patologia , Regulação para Baixo/genética , Regulação para Baixo/imunologia , Proteínas de Choque Térmico HSP27/genética , Proteínas de Choque Térmico HSP27/imunologia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Masculino , Camundongos , Camundongos Knockout , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Fatores de Tempo , Receptor 3 Toll-Like/genética , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
10.
J Stroke Cerebrovasc Dis ; 25(10): 2368-72, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27324301

RESUMO

OBJECTIVE: Our objective is to investigate the safety and long-term efficacy of the Wingspan stent (Boston Scientific, Natick, MA, USA) for treating severe atherosclerotic stenosis of the middle cerebral artery (MCA). METHODS: A total of 278 consecutive patients from our stroke database with clinical symptoms within the prior 90 days and intracranial atherosclerotic stenosis of 70% or above of the MCA were enrolled in this study between September 2012 and November 2014, and these patients were followed until the end of June 2015. The endpoint events included any stroke or death within 30 days after stenting and any subsequent ipsilateral ischemic stroke. RESULTS: Among the 278 enrolled patients, 277 patients (99.6%) successfully underwent stenting. The mean rate of stenosis decreased from 82.5 ± 7.9% to 9.0 ± 3.2% following treatment. Within 30 days after stenting, 12 patients (4.3%) experienced endpoint events, including 8 cases (2.9%) of hemorrhagic stroke and 4 cases (1.4%) of ischemic stroke; 2 perioperative deaths occurred. During 8-33 months of follow-up, 19 patients developed endpoint events. The 1- and 2-year endpoint event rates were 5.8% (95% confidence interval [CI], 5.0%-15.7%) and 7.2% (95% CI, 4.3%-10.1%), respectively. CONCLUSIONS: From this study, we can conclude that the treatment of severe symptomatic atherosclerotic stenosis of the MCA using the Wingspan stent was safe and effective and that the long-term stroke recurrence rate after stenting was low.


Assuntos
Arteriopatias Oclusivas/terapia , Procedimentos Endovasculares/instrumentação , Arteriosclerose Intracraniana/terapia , Artéria Cerebral Média , Stents , Idoso , Angiografia Digital , Arteriopatias Oclusivas/complicações , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/mortalidade , Isquemia Encefálica/etiologia , Angiografia Cerebral/métodos , Constrição Patológica , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Arteriosclerose Intracraniana/complicações , Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/mortalidade , Hemorragias Intracranianas/etiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/fisiopatologia , Desenho de Prótese , Recidiva , Sistema de Registros , Fatores de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/etiologia , Fatores de Tempo , Resultado do Tratamento
11.
J Neuroinflammation ; 12: 80, 2015 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-25928750

RESUMO

Increasing evidence suggests that toll-like receptors (TLRs) play an important role in cerebral ischemia-reperfusion injury. The endogenous ligands released from ischemic neurons activate the TLR signaling pathway, resulting in the production of a large number of inflammatory cytokines, thereby causing secondary inflammation damage following cerebral ischemia. However, the preconditioning for minor cerebral ischemia or the preconditioning with TLR ligands can reduce cerebral ischemic injury by regulating the TLR signaling pathway following ischemia in brain tissue (mainly, the inhibition of the TLR4/NF-κB signaling pathway and the enhancement of the interferon regulatory factor-dependent signaling), resulting in TLR ischemic tolerance. Additionally, recent studies found that postconditioning with TLR ligands after cerebral ischemia can also reduce ischemic damage through the regulation of the TLR signaling pathway, showing a significant therapeutic effect against cerebral ischemia. These studies suggest that the ischemic tolerance mediated by TLRs can serve as an important target for the prevention and treatment of cerebral ischemia. On the basis of describing the function and mechanism of TLRs in mediating cerebral ischemic damage, this review focuses on the mechanisms of cerebral ischemic tolerance induced by the preconditioning and postconditioning of TLRs and discusses the clinical application of TLRs for ischemic tolerance.


Assuntos
Isquemia Encefálica/metabolismo , Tolerância Imunológica/fisiologia , Receptores Toll-Like/metabolismo , Animais , Citocinas/metabolismo , Humanos
12.
Ann Neurol ; 75(6): 876-89, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24752976

RESUMO

OBJECTIVE: Inflammatory injury plays a critical role in intracerebral hemorrhage (ICH)-induced secondary brain injury. However, the upstream events that initiate inflammatory responses following ICH remain elusive. Our previous studies suggested that Toll-like receptor 4 (TLR4) may be the upstream signal that triggers inflammatory injury in ICH. In addition, recent clinical findings indicated that both TLR2 and TLR4 may participate in ICH-induced brain injury. However, it is unclear how TLR2 functions in ICH-induced inflammatory injury and how TLR2 interacts with TLR4. METHODS: The role of TLR2 and TLR2/TLR4 heterodimerization in ICH-induced inflammatory injury was investigated in both in vivo and in vitro models of ICH. RESULTS: TLR2 mediated ICH-induced inflammatory injury, which forms a heterodimer with TLR4 in both in vivo and in vitro models of ICH. Hemoglobin (Hb), but not other blood components, triggered inflammatory injury in ICH via assembly of TLR2/TLR4 heterodimers. MyD88 (myeloid differentiation primary response gene 88), but not TRIF (Toll/IR-1 domain-containing adaptor protein inducing interferon-beta), was required for ICH-induced TLR2/TLR4 heterodimerization. Mutation of MyD88 Arg196 abolished the TLR2/TLR4 heterodimerization. INTERPRETATION: Our results suggest that a novel TLR2/TLR4 heterodimer induced by Hb initiates inflammatory injury in ICH. Interfering with the assembly of the TLR2/TLR4 heterodimer may be a novel target for developing effective treatment of ICH.


Assuntos
Hemorragia Cerebral/complicações , Encefalite/etiologia , Encefalite/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Edema Encefálico/diagnóstico , Edema Encefálico/etiologia , Células Cultivadas , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas do Tecido Nervoso/metabolismo , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/etiologia , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/fisiologia , Receptor 2 Toll-Like/química , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/química , Receptor 4 Toll-Like/genética
13.
Inflamm Res ; 64(7): 487-95, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26021825

RESUMO

OBJECTIVE: Toll-like receptors (TLRs) that mediate inflammatory responses play an important role in epilepsy; however, whether TLR1 is also involved in epileptogenesis remains unclear. Thus, in this study, we investigated the extent and pattern of TLR1 expression in epileptic tissues. METHODS: One-hundred and thirty-two mice were intra-cerebroventricularly injected with PBS or kainic acid (KA) and were examined at 1, 3, 8 and 24 h. The expression pattern and distribution of TLR1 were examined by reverse-transcriptase polymerase chain reaction (RT-PCR), western blot analysis and immunohistochemistry staining. RESULTS: The mRNA and protein levels of TLR1 were significantly upregulated in the hippocampus and temporal cortex of epileptic mice compared with those of controls. TLR1 expression was increased as early as 1 h following KA treatment and peaked at 8 and 24 h. Immunohistochemistry staining demonstrated that TLR1 was distributed in the CA1-3, dentate gyrus and hilus regions of the hippocampus and different cortical regions. Immunofluorescent staining further revealed that TLR1 was primarily expressed in the neurons, microglia, and astrocytes of epileptogenic tissue. SIGNIFICANCE: These results demonstrate that cortical and hippocampal sub-regional expression of TLR1 is altered during epileptogenesis in a time- and location-specific manner, suggesting a close association with the process of epilepsy.


Assuntos
Química Encefálica/genética , Agonistas de Aminoácidos Excitatórios , Ácido Caínico , Convulsões/induzido quimicamente , Convulsões/genética , Receptor 1 Toll-Like/biossíntese , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/genética , Imuno-Histoquímica , Injeções Intraventriculares , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptor 1 Toll-Like/genética , Regulação para Cima/efeitos dos fármacos
14.
Neurol Sci ; 36(10): 1843-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26024728

RESUMO

Iron plays a detrimental role in the intracerebral hemorrhage (ICH)-induced brain damage, while hepcidin is the most important iron-regulated hormone. Here, we investigate the association between serum hepcidin and serum iron, outcome in patients with ICH. Serum samples of 81 cases with ICH were obtained on consecutive days to detect the levels of hepcidin, iron, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The National Institutes of Health Stroke Scale score (NIHSS) was measured at admission and on days 7 and 30, and the modified Rankin Scale (mRS) score was evaluated at 3 months after ICH. Additionally, the correlations of serum hepcidin with serum iron and the mRS score were analyzed by a generalized linear model. Higher serum hepcidin levels were detected in patients with poor outcomes (P < 0.001), and the mRS score increased by a mean of 1.135 points (95% CI 1.021-1.247, P < 0.001) for every serum hepcidin quartile after adjusting for other prognostic variables. Pearson correlation analysis showed that serum hepcidin was negatively correlated with serum iron (r = -0.5301, P < 0.001), and a significantly lower concentration of serum iron was found in patients with poor outcomes (P = 0.007). Additionally, serum hepcidin was independently correlated with mRS scores of ICH patients (OR 1.115, 95% CI 0.995-1.249, P = 0.021). Our results suggest that serum hepcidin is closely related to the outcome of patients with ICH and may be a biological marker for outcome prediction.


Assuntos
Hemorragia Cerebral/sangue , Hepcidinas/sangue , Ferro/sangue , Biomarcadores/sangue , Análise Química do Sangue , Hemorragia Cerebral/diagnóstico , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Interleucina-6/sangue , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/sangue
16.
Theranostics ; 14(11): 4297-4317, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113798

RESUMO

Aim: Although lactate supplementation at the reperfusion stage of ischemic stroke has been shown to offer neuroprotection, whether the role of accumulated lactate at the ischemia phase is neuroprotection or not remains largely unknown. Thus, in this study, we aimed to investigate the roles and mechanisms of accumulated brain lactate at the ischemia stage in regulating brain injury of ischemic stroke. Methods and Results: Pharmacological inhibition of lactate production by either inhibiting LDHA or glycolysis markedly attenuated the mouse brain injury of ischemic stroke. In contrast, additional lactate supplement further aggravates brain injury, which may be closely related to the induction of neuronal death and A1 astrocytes. The contributing roles of increased lactate at the ischemic stage may be related to the promotive formation of protein lysine lactylation (Kla), while the post-treatment of lactate at the reperfusion stage did not influence the brain protein Kla levels with neuroprotection. Increased protein Kla levels were found mainly in neurons by the HPLC-MS/MS analysis and immunofluorescent staining. Then, pharmacological inhibition of lactate production or blocking the lactate shuttle to neurons showed markedly decreased protein Kla levels in the ischemic brains. Additionally, Ldha specific knockout in astrocytes (Aldh1l1 CreERT2; Ldha fl/fl mice, cKO) mice with MCAO were constructed and the results showed that the protein Kla level was decreased accompanied by a decrease in the volume of cerebral infarction in cKO mice compared to the control groups. Furthermore, blocking the protein Kla formation by inhibiting the writer p300 with its antagonist A-485 significantly alleviates neuronal death and glial activation of cerebral ischemia with a reduction in the protein Kla level, resulting in extending reperfusion window and improving functional recovery for ischemic stroke. Conclusion: Collectively, increased brain lactate derived from astrocytes aggravates ischemic brain injury by promoting the protein Kla formation, suggesting that inhibiting lactate production or the formation of protein Kla at the ischemia stage presents new therapeutic targets for the treatment of ischemic stroke.


Assuntos
Astrócitos , AVC Isquêmico , Ácido Láctico , Neurônios , Animais , Astrócitos/metabolismo , Camundongos , Ácido Láctico/metabolismo , Masculino , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Neurônios/metabolismo , Neurônios/patologia , Modelos Animais de Doenças , Camundongos Knockout , Encéfalo/metabolismo , Encéfalo/patologia , Camundongos Endogâmicos C57BL , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Lesões Encefálicas/metabolismo , Lactato Desidrogenase 5/metabolismo , Fármacos Neuroprotetores/farmacologia
17.
Stroke ; 44(9): 2545-52, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23839500

RESUMO

BACKGROUND AND PURPOSE: Accumulating evidence indicates that inflammatory responses cause secondary injury after intracerebral hemorrhage (ICH). We recently demonstrated the involvement of toll-like receptor 4 (TLR4) signaling in these processes. The purpose of the current study was to investigate the protective effect and mechanism of TAK-242 (Ethyl (6R)-6-[N-(2-chloro-4-fluorophenyl) sulfamoyl] cyclohex-1-ene-1 -carboxylate, Takeda), a TLR4 antagonist, in an ICH mouse model. METHODS: TAK-242 was intraperitoneally injected 6 hours after ICH once daily for 5 successive days. We assessed neurological deficit scores; changes in brain water content; and levels of inflammatory factors, DNA damage, and neuronal degeneration in perihematomal region 1, 3, and 5 days after ICH. Peripheral inflammatory cell infiltration was determined using flow cytometry; and the expression of TLR4 downstream signaling molecules was assessed by Western blot. RESULTS: TAK-242 significantly reduced brain water content, neurological deficit scores, and levels of inflammatory factors. The levels of DNA damage and neuronal degeneration were also significantly decreased, as was peripheral inflammatory cell infiltration. The expression of TLR4 downstream signaling molecules, including myeloid differentiation primary response gene 88, toll/IR-1(TIR)-domain-containing adaptor protein inducing interferon-beta IκBα, nuclear factor-κBp65, and phosphorylated nuclear factor-κBp65, was significantly downregulated. CONCLUSIONS: The results suggest that TLR4 antagonist reduced inflammatory injury and neurological deficits in a mouse model of ICH. The mechanism may involve decreased expression of signaling molecules downstream of TLR4.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/etiologia , Hemorragia Cerebral/tratamento farmacológico , Mediadores da Inflamação/administração & dosagem , Sulfonamidas/toxicidade , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Comportamento Animal/efeitos dos fármacos , Lesões Encefálicas/diagnóstico , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico , Modelos Animais de Doenças , Regulação para Baixo/efeitos dos fármacos , Mediadores da Inflamação/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/administração & dosagem , Receptor 4 Toll-Like/genética
18.
Neurol India ; 71(2): 323-325, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37148061

RESUMO

Mitochondrial neurogastrointestinal encephalopathy (MNGIE) is an autosomal recessive disease associated with the mutation of the TYMP gene. MNGIE causes gastrointestinal and neurological symptoms, and the gastrointestinal symptoms are usually notable, which may lead to misdiagnosis. However, we herein report a 29-year-old female who presented with prominent neurological symptoms, while her gastrointestinal symptoms were mild. Brain MRI revealed prominent diffused leukoencephalopathy and peripheral neuropathy was confirmed by the nerve conduction velocity test. Biochemical tests showed elevated plasma thymidine, deoxyuridine, and lactate levels. Molecular genetic testing demonstrated a novel homozygous TYMP c. 447 dupG mutation and the patient's mother was heterozygous for the mutation but had no clinical features. MNGIE was diagnosed based on the results. Unlike other patients who had notable gastrointestinal symptoms, this patient presented with more prominent neurological symptoms than gastrointestinal symptoms, which might have been caused by the novel mutation in the TYMP gene.


Assuntos
Encefalomiopatias Mitocondriais , Humanos , Feminino , Adulto , Encefalomiopatias Mitocondriais/complicações , Encefalomiopatias Mitocondriais/diagnóstico , Encefalomiopatias Mitocondriais/genética , Timidina Fosforilase/genética , Mutação/genética , Testes Genéticos
19.
Front Pharmacol ; 14: 1091616, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36814490

RESUMO

Cerebral ischemia, resulting from compromised blood flow, is one of the leading causes of death worldwide with limited therapeutic options. Potential deleterious injuries resulting from reperfusion therapies remain a clinical challenge for physicians. This study aimed to explore the metabolomic alterations during ischemia-reperfusion injury by employing metabolomic analysis coupled with gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) and ultraperformance liquid chromatography quadrupole (UPLC/Q)-TOF-MS. Metabolomic data from mice subjected to middle cerebral artery occlusion (MCAO) followed by reperfusion (MCAO/R) were compared to those of the sham and MCAO groups. A total of 82 simultaneously differentially expressed metabolites were identified among each group. The top three major classifications of these differentially expressed metabolites were organic acids, lipids, and organooxygen compounds. Metabolomics pathway analysis was conducted to identify the underlying pathways implicated in MCAO/R. Based on impactor scores, the most significant pathways involved in the response to the reperfusion after cerebral ischemia were glycerophospholipid metabolism, linoleic acid metabolism, pyrimidine metabolism, and galactose metabolism. 17 of those 82 metabolites were greatly elevated in the MCAO/Reperfusion group, when compared to those in the sham and MCAO groups. Among those metabolites, glucose-6-phosphate 1, fructose-6-phosphate, cellobiose 2, o-phosphonothreonine 1, and salicin were the top five elevated metabolites in MCAO/R group, compared with the MCAO group. Glycolysis, the pentose phosphate pathway, starch and sucrose metabolism, and fructose and mannose degradation were the top four ranked pathways according to metabolite set enrichment analysis (MSEA). The present study not only advances our understanding of metabolomic changes among animals in the sham and cerebral ischemia groups with or without reperfusion via metabolomic profiling, but also paves the way to explore potential molecular mechanisms underlying metabolic alteration induced by cerebral ischemia-reperfusion.

20.
Am J Chin Med ; 51(5): 1127-1151, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37335209

RESUMO

The brain metabolic changes caused by the interruption of blood supply are the initial factors of brain injury in ischemic stroke. Electroacupuncture (EA) pretreatment has been shown to protect against ischemic stroke, but whether its neuroprotective mechanism involves metabolic regulation remains unclear. Based on our finding that EA pretreatment significantly alleviated ischemic brain injury in mice by reducing neuronal injury and death, we performed a gas chromatography-time of flight mass spectrometry (GC-TOF/MS) to investigate the metabolic changes in the ischemic brain and whether EA pretreatment influenced these changes. First, we found that some glycolytic metabolites in the normal brain tissues were reduced by EA pretreatment, which may lay the foundation of neuroprotection for EA pretreatment against ischemic stroke. Then, 6[Formula: see text]h of cerebral ischemia-induced brain metabolic changes, especially the enhanced glycolysis, were partially reversed by EA pretreatment, which was manifested by the brain levels of 11 of 35 up-regulated metabolites and 18 of 27 down-regulated metabolites caused by cerebral ischemia significantly decreasing and increasing, respectively, due to EA pretreatment. A further pathway analysis showed that these 11 and 18 markedly changed metabolites were mainly involved in starch and sucrose metabolism, purine metabolism, aspartate metabolism, and the citric acid cycle. Additionally, we found that EA pretreatment raised the levels of neuroprotective metabolites in both normal and ischemic brain tissues. In conclusion, our study revealed that EA pretreatment may attenuate the ischemic brain injury by inhibiting glycolysis and increasing the levels of some neuroprotective metabolites.


Assuntos
Lesões Encefálicas , Isquemia Encefálica , Eletroacupuntura , AVC Isquêmico , Traumatismo por Reperfusão , Acidente Vascular Cerebral , Camundongos , Animais , Eletroacupuntura/métodos , Neuroproteção , Isquemia Encefálica/metabolismo , Metabolômica , Traumatismo por Reperfusão/prevenção & controle , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle
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