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After ischemic stroke (IS), secondary injury is intimately linked to endoplasmic reticulum (ER) stress and body-brain crosstalk. Nonetheless, the underlying mechanism systemic immune disorder mediated ER stress in human IS remains unknown. In this study, 32 candidate ER stress-related genes (ERSRGs) were identified by overlapping MSigDB ER stress pathway genes and DEGs. Three Key ERSRGs (ATF6, DDIT3 and ERP29) were identified using LASSO, random forest, and SVM-RFE. IS patients with different ERSRGs profile were clustered into two groups using consensus clustering and the difference between 2 group was further explored by GSVA. Through immune cell infiltration deconvolution analysis, and middle cerebral artery occlusion (MCAO) mouse scRNA analysis, we found that the expression of 3 key ERSRGs were closely related with peripheral macrophage cell ER stress in IS and this was further confirmed by RT-qPCR experiment. These ERS genes might be helpful to further accurately regulate the central nervous system and systemic immune response through ER stress and have potential application value in clinical practice in IS.
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Biologia Computacional , Estresse do Retículo Endoplasmático , Aprendizado de Máquina , Humanos , Estresse do Retículo Endoplasmático/genética , Estresse do Retículo Endoplasmático/fisiologia , Camundongos , Animais , Acidente Vascular Cerebral/genética , AVC Isquêmico/genética , AVC Isquêmico/metabolismo , MasculinoRESUMO
Under subarachnoid hemorrhage (SAH) conditions, astrocytes undergo a marked intensification of glycolytic activity, resulting in the generation of substantial amounts of lactate to maintain the energy demand for neurons and other brain cells. Lactate has garnered increasing attention in recent years because of its emerging role in critical biological processes such as inflammation regulation and neuroprotection, particularly through its histone lactylation. Bromodomain-containing protein 4 (BRD4) plays a crucial role in maintaining neural development and promoting memory formation in the central nervous system. Nonetheless, the function and regulatory mechanism of BRD4 and histone lactylation in astrocytes following SAH remain elusive. Our findings indicate that BRD4, a crucial epigenetic regulator, plays a definitive role in histone lactylation. Both in vitro and in vivo, these results demonstrated that targeted silencing of BRD4 in astrocytes can significantly reduce H4K8la lactylation, thereby aggravating the A1 polarization of astrocytes and ultimately affecting the recovery of neural function and prognosis in mice after SAH. In summary, BRD4 plays a pivotal role in modulating astrocyte polarization following SAH via histone lactylation. Targeting this mechanism might offer an efficient therapeutic strategy for SAH.
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Astrócitos , Proteínas que Contêm Bromodomínio , Histonas , Hemorragia Subaracnóidea , Fatores de Transcrição , Animais , Masculino , Camundongos , Astrócitos/metabolismo , Proteínas que Contêm Bromodomínio/metabolismo , Polaridade Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Histonas/metabolismo , Camundongos Endogâmicos C57BL , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Hemorragia Subaracnóidea/metabolismo , Hemorragia Subaracnóidea/patologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
OBJECTIVES: To explore the role of endothelial-mesenchymal transition (EndMT) mediated by the TGF-ß/SMAD signalling pathway in the pathogenesis of ankylosing spondylitis (AS). METHODS: Serum levels of TGF-ß1 were measured by enzyme-linked immunosorbent assay (ELISA) in 48 patients with AS and 15 healthy subjects. The expression levels of TGF-ß1, SMAD7, CTGF, CD34 and EndMT-related markers (α-SMA, vimentin, FSP-1, VE-cadherin) in the sacroiliac joint (SIJ) of three AS patients were detected by immunohistochemistry, and three non-spondyloarthritis (SpA) autopsy samples were used as controls. RESULTS: Serum TGF-ß1 level of AS patients was significantly higher than that of healthy controls (22971 ± 7667 pg/ml vs. 14837±4653 pg/ml, p<0.01). Compared with the non-SpA control group, the microvascular density (MVD) at the pannus formation site of SIJ in AS patients was significantly increased, accompanied by respectively increased expressions of TGF-ß1, CTGF, α-SMA, vimentin, and FSP-1 (all p<0.05), whereas respectively decreased expressions of VE-cadherin and SMAD7 (p<0.01). The expression level of FSP-1 was positively correlated with levels of TGF-ß1 and MVD, and negatively correlated with SMAD7. CONCLUSIONS: Our findings show that EndMT is involved in the promotion of pannus formation by TGF-ß/SMAD signalling pathway activation in AS.
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Microglial necroptosis exacerbates neurodegenerative diseases, central nervous system (CNS) injury, and demonstrates a proinflammatory process, but its contribution to subarachnoid hemorrhage (SAH) is poorly characterized. BCL-2 homologous antagonist-killer protein (Bak1), a critical regulatory molecule of endogenous apoptosis, can be involved in the pathologic process of necroptosis by regulating mitochondrial permeability. In this study, we revealed microglia undergo necroptosis after SAH in vivo and vitro. Western blot revealed that Bak1 was elevated at 24 h after SAH. Knocked down of Bak1 by adeno-associated virus attenuates microglial necroptosis, alleviates neuroinflammation, and improves neurologic function after SAH in mice. Furthermore, oxyhemoglobin (10 µM) induced necroptosis in BV2 microglia, increasing Bak1 expression and mediating proinflammatory phenotype transformation, exacerbating oxidative stress and neuroinflammation. Abrogating BV2 Bak1 could reduce necroptosis by down-regulating the expression of phosphorylated pseudokinase mixed lineage kinase domain-like protein (p-MLKL), then down-regulating proinflammatory phenotype gene expression. RNA-Seq showed that disrupting BV2 Bak1 down-regulates multiple immune and inflammatory pathways and ameliorates cell injury by elevating thrombospondin 1 (THBS1) expression. In summary, we identified a critical regulatory role for Bak1 in microglial necroptosis and neuroinflammation after SAH. Bak1 is expected to be a potential target for the treatment strategy of SAH.
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Doenças Neuroinflamatórias , Hemorragia Subaracnóidea , Camundongos , Animais , Microglia/metabolismo , Hemorragia Subaracnóidea/metabolismo , Necroptose , Proteína Killer-Antagonista Homóloga a bcl-2/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Neuroinflammation has been reported to be associated with white matter injury (WMI) after subarachnoid hemorrhage (SAH). As the main resident immune cells of the brain, microglia can be activated into proinflammatory and anti-inflammatory phenotypes. Toll-like receptor 4 (TLR4), expressed on the surface of the microglia, plays a key role in microglial inflammation. However, the relationship between TLR4, microglial polarization, and WMI following SAH remains unclear. In this study, a total of 121 male adult C57BL/6 wild-type (WT) mice, 20 WT mice at postnatal day 1 (P1), and 41 male adult TLR4 gene knockout (TLR4-/-) mice were used to investigate the potential role of TLR4-induced microglial polarization in early WMI after SAH by radiological, histological, microstructural, transcriptional, and cytological evidence. The results indicated that microglial inflammation was associated with myelin loss and axon damage, shown as a decrease in myelin basic protein (MBP), as well as increase in degraded myelin basic protein (dMBP) and amyloid precursor protein (APP). Gene knockout of TLR4 revised microglial polarization toward the anti-inflammatory phenotype and protected the white matter at an early phase after SAH (24 h), as shown through reduction of toxic metabolites, preservation of myelin, reductions in APP accumulation, reductions in white matter T2 hyperintensity, and increases in FA values. Cocultures of microglia and oligodendrocytes, the cells responsible for myelin production and maintenance, were established to further elucidate the relationship between microglial polarization and WMI. In vitro, TLR4 inhibition decreased the expression of microglial MyD88 and phosphorylated NF-κB, thereby inhibiting M1 polarization and mitigating inflammation. Decrease in TLR4 in the microglia increased preservation of neighboring oligodendrocytes. In conclusion, microglial inflammation has dual effects on early WMI after experimental SAH. Future explorations on more clinically relevant methods for modulating neuroinflammation are warranted to combat stroke with both WMI and gray matter destruction.
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Lesões Encefálicas , Hemorragia Subaracnóidea , Substância Branca , Camundongos , Animais , Masculino , Microglia/metabolismo , Hemorragia Subaracnóidea/metabolismo , Receptor 4 Toll-Like/metabolismo , Proteína Básica da Mielina/metabolismo , Proteína Básica da Mielina/farmacologia , Substância Branca/patologia , Doenças Neuroinflamatórias , Camundongos Endogâmicos C57BL , Inflamação/patologia , Lesões Encefálicas/patologia , Anti-Inflamatórios/farmacologiaRESUMO
BACKGROUND: Primary familial brain calcification (PFBC), habitually called Fahr's disease, is characterized by bilateral calcification of the basal ganglia, accompanied by extensive calcification of the cerebellar dentate nucleus, brainstem cerebrum, and cerebellum at the grey-white matter junction. However, there are few reports about PFBC with aneurysmal subarachnoid hemorrhage (aSAH) and thalassemia. CASE PRESENTATION: We describe a patient admitted to the hospital with an acute deterioration in the level of consciousness with no history of neuropsychiatric features or movement disorders. After computed tomography (CT) and CT angiography (CTA), the patient was diagnosed with PFBC, accompanied by aneurysmal subarachnoid haemorrhage (aSAH), intracranial haemorrhage (ICH), and hemoglobin electrophoresis suggested beta-thalassemia. This patient underwent craniotomy aneurysm clipping and intracranial hematoma removal. CONCLUSIONS: For patients with PFBC, we should pay attention to their blood pressure and intracranial vascular conditions. The CTA is necessary to clarify the cerebrovascular conditions of the patient, especially when combined with hypertension and persistent headache or other related prodromal symptoms of cerebrovascular disease.
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Doenças dos Gânglios da Base , Transtornos Cerebrovasculares , Hemorragia Subaracnóidea , Talassemia beta , Humanos , Hemorragia Subaracnóidea/complicações , Talassemia beta/complicações , Doenças dos Gânglios da Base/diagnóstico , Transtornos Cerebrovasculares/complicações , Gânglios da BaseRESUMO
More than 7000 per- and polyfluorinated alkyl substances (PFAS) have been documented in the U.S. Environmental Protection Agency's CompTox Chemicals database. These PFAS can be used in a broad range of industrial and consumer applications but may pose potential environmental issues and health risks. However, little is known about emerging PFAS bioaccumulation to assess their chemical safety. This study focuses specifically on the large and high-quality data set of fluorochemicals from the related environmental and pharmaceutical chemicals databases, and machine learning (ML) models were developed for the classification prediction of the unbound fraction of compounds in plasma. A comprehensive evaluation of the ML models shows that the best blending model yields an accuracy of 0.901 for the test set. The predictions suggest that most PFAS (â¼92%) have a high binding fraction in plasma. Introduction of alkaline amino groups is likely to reduce the binding affinities of PFAS with plasma proteins. Molecular dynamics simulations indicate a clear distinction between the high and low binding fractions of PFAS. These computational workflows can be used to predict the bioaccumulation of emerging PFAS and are also helpful for the molecular design of PFAS to prevent the release of high-bioaccumulation compounds into the environment.
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As a kind of class II medical device, medical optical radiation protective eyewears should meet the requirements of safety and effectiveness. In this study, the evaluation system of medical optical radiation protective eyewears is established. Combined with the medical device registration unit division guidelines, the classification method of medical optical radiation protective eyewears is given. Medical optical radiation protective eyewears are not only assembled spectacles, but also have special optical radiation protection performance. The performance evaluation method of medical optical radiation protective eyewears and the evaluation method of shelf life for medical optical radiation protective eyewears are given.
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Proteção RadiológicaRESUMO
As an important initiator and responder of brain inflammation in the central nervous system (CNS), astrocytes transform into two new reactive phenotypes with changed morphology, altered gene expression and secretion profiles, termed detrimental A1 and beneficial A2. Inflammatory events have been shown to occur during the phase of early brain injury (EBI) after subarachnoid hemorrhage (SAH). However, the phenotype transformation of astrocytes as well as its potential contribution to inflammatory status in the EBI of SAH has yet to be determined. In the present study, both in vivo and in vitro models of SAH were established, and the polarization of astrocytes after SAH was analyzed by RNA-seq, western blotting, and immunofluorescence staining. The effect of astrocytic phenotype transformation on neuroinflammation was examined by real-time quantitative PCR (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). We demonstrated that astrocytes were transformed into A1 astrocytes and caused neuronal death through the release of pro-inflammatory factors in EBI after SAH. Importantly, Ponesimod, an S1PR1 specific modulator, exerted neuroprotective effects through the prevention of astrocytic polarization to the A1 phenotype as proved by immunofluorescence, neurological tests, and TUNEL study. We also revealed the role of Ponesimod in modulating astrocytic response was mediated by the signal transducer and activator of transcription 3 (STAT3) signaling. Our study suggested that Ponesimod may be a promising therapeutic target for the treatment of brain injury following SAH.
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Astrócitos/efeitos dos fármacos , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/patologia , Morte Celular/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Hemorragia Subaracnóidea/patologia , Tiazóis/uso terapêutico , Animais , Lesões Encefálicas/psicologia , Polaridade Celular/efeitos dos fármacos , Encefalite/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Desempenho Psicomotor/efeitos dos fármacos , Fator de Transcrição STAT3 , Transdução de Sinais/efeitos dos fármacos , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Hemorragia Subaracnóidea/psicologia , Tiazóis/farmacologiaRESUMO
Subcellular localization of transcripts is highly associated with regulation of gene expression, synthesis of protein, and also the development of the human brain cortex. Although many mechanisms are prevalent in the occurrence of neuroinflammation, the mechanisms based on differences in subcellular localization of transcripts have not been explored. To characterize the dynamic profile of nuclear and cytoplasmic transcripts during the progress of haemorrhage-induced neuroinflammation, we isolated nucleo-cytoplasmic RNA fractions of oxyhaemoglobin (oxy-Hb) treated microglia cells and sequenced both fractions. We discovered that cytoplasmic retained genes were the major forces to maintain the neuroinflammatory microenvironment with 10 hub genes and 40 conserved genes were identified. Moreover, antisense RNA Gm44096 and lincRNA Gm47270, which co-expressed with a crowd of inflammatory genes in the cytoplasm, were discovered as regulatory strategies for sustaining the neuroinflammatory microenvironment. Thus, our study provides a new perspective on understanding haemorrhage-induced neuroinflammation and also reveals a mechanism of lncRNA responsible for maintaining the neuroinflammatory microenvironment.
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Núcleo Celular/metabolismo , Microambiente Celular/genética , Citoplasma/metabolismo , Doenças Neuroinflamatórias/etiologia , Transporte de RNA , Animais , Linhagem Celular , Núcleo Celular/genética , Biologia Computacional/métodos , Citoplasma/genética , Modelos Animais de Doenças , Suscetibilidade a Doenças , Perfilação da Expressão Gênica , Ontologia Genética , Hemorragia/complicações , Camundongos , Microglia/metabolismo , Doenças Neuroinflamatórias/metabolismo , RNA Longo não Codificante/genéticaRESUMO
Neuroinflammation can be caused by various factors in early brain injury after subarachnoid hemorrhage (SAH). One of the most important features of this process is M1 microglial activation. In turn, the TLR4/NF-κB pathway plays an essential role in activating M1 phenotypic microglia. Biglycan, a small leucine-rich proteoglycan, functions as an endogenous ligand of TLR4 and TLR2 in macrophages. However, the underlying mechanisms associated with microglial activation in stroke pathogenesis are poorly understood. Here, we aimed to identify the role of biglycan in neuroinflammation following SAH. In our study, SAH was induced by endovascular perforation in young male C57BL/6J mice. Lentiviral vector was administered intracerebroventricularly to knock down Biglycan. Post-SAH assessments included neurobehavioral tests, immunofluorescence, western blot, qRT-PCR, Co-IP, flow cytometry, and ELISA. The biglycan level was markedly elevated following SAH in vivo. Of particularly note, knockdown of biglycan significantly improved neurological outcomes. TLR4 was bound with soluble biglycan in vitro. In addition, biglycan down-regulation suppressed the expression of phosphorylated-NF-κB p65 (p-NF-κB) and inducible nitric oxide synthase (iNOS), as well as the cytokine (TNF-α, IL-1ß, and IL-6) production in vivo and in vitro. Moreover, we detected a decreased expression of CD16/32 and CD86, M1 markers when biglycan was inhibited in vitro. Our work suggests that biglycan can induce neuroinflammation by promoting M1 microglial activation at least in part through TLR4/NF-κB signaling pathway after experimental SAH. Targeting biglycan may be a promising strategy for the clinical management of SAH.
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Biglicano/metabolismo , Inflamação/metabolismo , Microglia/metabolismo , Hemorragia Subaracnóidea/metabolismo , Animais , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais/fisiologia , Hemorragia Subaracnóidea/patologiaRESUMO
BACKGROUND: Neuroinflammation is an important host defense response to secondary brain injury after intracerebral hemorrhage (ICH). Triggering receptor expressed on myeloid cells 2 (TREM2) confers strong neuroprotective effects by attenuating neuroinflammation in experimental ischemic stroke. Recent studies suggest that apolipoprotein E (apoE) is a novel, high-affinity ligand of TREM2. This study aimed to investigate the effects of TREM2 activation on neuroinflammation and neuronal apoptosis in a mouse model of ICH. METHODS: Adult male CD1 mice (n = 216) were subjected to intrastriatal injection of bacterial collagenase. The TREM2 ligand, apoE-mimetic peptide COG1410 was administered intranasally at 1 h after ICH induction. To elucidate the underlying mechanism, TREM2 small interfering RNA (siRNA) and the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 were administered intracerebroventricularly prior to COG1410 treatment. Neurobehavioral tests, brain water content, immunofluorescence, western blotting, and Fluoro-Jade C- and terminal deoxynucleotidyl transferase dUTP nick end labeling staining were performed. RESULTS: Endogenous TREM2 expression was increased and peaked at 24 h after ICH. TREM2 was expressed on microglia, astrocytes, and neurons. COG1410 improved both short-term and long-term neurological functions, reduced brain edema, inhibited microglia/macrophage activation and neutrophil infiltration, and suppressed neuronal apoptotic cell death in perihematomal areas after ICH. Knockdown of endogenous TREM2 by TREM2 siRNA aggravated neurological deficits and decreased the expression of TREM2 in naïve and ICH mice. COG1410 was associated with upregulation of TREM2, PI3K, phosphorylated-Akt, and Bcl-2 and downregulation of TNF-α, IL-1ß, and Bax after ICH. The neuroprotective effects of COG1410 were abolished by both TREM2 siRNA and PI3K inhibitor LY294002. CONCLUSIONS: Our finding demonstrated that TREM2 activation improved neurological functions and attenuated neuroinflammation and neuronal apoptosis after ICH, which was, at least in part, mediated by activation of PI3K/Akt signaling pathway. Therefore, activation of TREM2 may be a potential therapeutic strategy for the management of ICH patients.
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Hemorragia Cerebral/patologia , Inflamação/patologia , Glicoproteínas de Membrana/metabolismo , Neurônios/patologia , Receptores Imunológicos/metabolismo , Animais , Apoptose/fisiologia , Hemorragia Cerebral/metabolismo , Inflamação/metabolismo , Masculino , Camundongos , Neurônios/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologiaRESUMO
Based on the analysis of the theoretical calculation model of axial resolution of optical coherence tomograph for the posterior segment of the human eye, a set of testing device for measuring its axial resolution is designed and developed. In view of a commercial ophthalmic optical coherence tomograph in clinical use, its axial resolution is calculated to be 5.07 µm theoretically, and the actual measurement value is 5.45 µm. The uncertainty of the detection device is evaluated and the result is (5.45±0.10) µm. The measurement error introduced by the testing device is very small. Meanwhile, the axial resolution measured by the testing device meets the requirements of the instrument(≤ 6 µm).
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Algoritmos , Olho/diagnóstico por imagem , Tomografia de Coerência Óptica , Humanos , IncertezaRESUMO
Background and Purpose- Mitoquinone has been reported as a mitochondria-targeting antioxidant to promote mitophagy in various chronic diseases. Here, our aim was to study the role of mitoquinone in mitophagy activation and oxidative stress-induced neuronal death reduction after subarachnoid hemorrhage (SAH) in rats. Methods- Endovascular perforation was used for SAH model of male Sprague-Dawley rats. Exogenous mitoquinone was injected intraperitoneally 1 hour after SAH. ML385, an inhibitor of Nrf2 (nuclear factor-E2-related factor 2), was given intracerebroventricularly 24 hours before SAH. Small interfering RNA for PHB2 (prohibitin 2) was injected intracerebroventricularly 48 hours before SAH. Nuclear, mitochondrial, and cytoplasmic fractions were gathered using nucleus and mitochondria isolation kits. SAH grade evaluation, short- and long- term neurological function tests, oxidative stress, and apoptosis measurements were performed. Pathway related proteins were investigated with Western blot and immunofluorescence staining. Results- Expression of Keap1 (Kelch-like epichlorohydrin-associated protein 1, 2.84× at 24 hours), Nrf2 (2.78× at 3 hours), and LC3II (light chain 3-II; 1.94× at 24 hours) increased, whereas PHB2 (0.46× at 24 hours) decreased after SAH compared with sham group. Mitoquinone treatment attenuated oxidative stress and neuronal death, both short-term and long-term. Administration of mitoquinone resulted in a decrease in expression of Keap1 (0.33×), Romo1 (reactive oxygen species modulator 1; 0.24×), Bax (B-cell lymphoma-2 associated X protein; 0.31×), Cleaved Caspase-3 (0.29×) and an increase in Nrf2 (2.13×), Bcl-xl (B-cell lymphoma-extra large; 1.67×), PINK1 (phosphatase and tensin-induced kinase 1; 1.67×), Parkin (1.49×), PHB2 (1.60×), and LC3II (1.67×) proteins compared with SAH+vehicle group. ML385 abolished the treatment effects of mitoquinone on behavior and protein levels. PHB2 small interfering RNA reversed the outcomes of mitoquinone administration through reduction in protein expressions downstream of PHB2. Conclusions- Mitoquinone inhibited oxidative stress-related neuronal death by activating mitophagy via Keap1/Nrf2/PHB2 pathway after SAH. Mitoquinone may serve as a potential treatment to relieve brain injury after SAH.
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Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Mitofagia/fisiologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Repressoras/metabolismo , Transdução de Sinais/fisiologia , Hemorragia Subaracnóidea/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Masculino , Compostos Organofosforados/farmacologia , Ratos , Ratos Sprague-Dawley , Ubiquinona/análogos & derivados , Ubiquinona/farmacologiaRESUMO
BACKGROUND: This study aimed to study the effect and underlying molecular mechanisms of single-nucleotide polymorphism (SNP) rs767649 during the pathogenesis of intracranial aneurysm (IA) rupture. METHOD: Real-time PCR and Western blot analysis were performed to detect the differentiated expression of miR-155 and matrix metalloproteinase-2 (MMP-2) among different sample groups. Computational analysis and luciferase assay were conducted to study the effect of SNP rs767649 on the expression of miR-155 as well as the regulatory relationship between miR-155 and MMP-2. RESULTS: In unruptured IA samples, the expression of miR-155 was upregulated while the expression of MMP-2 was downregulated compared with the ruptured IA samples. Similarly, the expression of miR-155 was upregulated while the expression of MMP-2 was downregulated in samples genotyped as AA/AT compared with samples genotyped as TT. In addition, compared with the negative controls, the luciferase activities of cells treated with rs767649A and rs767649T were both elevated with rs767649A-transfected cells expressing the highest luciferase activity. Furthermore, a negative relationship was established between miR-155 and MMP-2 by measuring the luciferase activity of cells cotransfected with miR-155 and the wild-type 3'-untranslated region of MMP-2. CONCLUSION: The results of this study showed that the SNP rs767649 in the promoter of miR-155 could reduce the transcription activity of miR-155, while poorly expressed miR-155 could increase the incidence of IA rupture by increasing the expression of MMP-2, especially in subjects carrying the TT genotype of SNP rs767649.
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Aneurisma Roto/complicações , Aneurisma Intracraniano/complicações , Hemorragias Intracranianas/genética , MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , Regiões 3' não Traduzidas/genética , Feminino , Regulação da Expressão Gênica , Genótipo , Humanos , Hemorragias Intracranianas/etiologia , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
Cerebral hemorrhage (ICH) is a common cerebrovascular condition with high mortality, disability and recurrence rates. TLR4-mediated acute inflammatory injury plays a pivotal role in ICH. Verbascoside (VB) is an active component of multiple medicinal plants, and exerts neuroprotective effects in ischemic stroke by targeting the inflammatory response. However, the effects of VB on ICH and the underlying mechanisms remain unclear. In this study, we analyzed the therapeutic effects of VB on acute ICH, and the possible involvement of TLR4-mediated inflammation. VB improved the behavioral score and reduced the hematoma volume, brain edema and neuronal apoptosis in a murine model of acute ICH. Mechanistically, VB attenuated macroglia activation and decreased inflammatory factor levels, which in turn protected the neurons. Furthermore, TLR4 knockout abolished the effects of VB both in vivo and in vitro. Taken together, VB attenuates the symptoms of ICH by targeting the TLR4-mediated acute inflammatory response.
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Edema Encefálico/prevenção & controle , Hemorragia Cerebral/prevenção & controle , Glucosídeos/farmacologia , Inflamação/prevenção & controle , Fenóis/farmacologia , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Edema Encefálico/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Plantas Medicinais/química , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismoRESUMO
Objective: The endovascular filament-perforation model turned out to become the most popular one for the reproduction of prominent pathophysiological features observed after human subarachnoid haemorrhage (SAH). However, few studies have considered methods that may minimize surgically induced injury. This study described an improved and simplified surgical procedure in which a single clip is placed at the external carotid artery (ECA). Method: Male C57BL/6 mice were given either a classic endovascular filament SAH model, improved endovascular filament SAH model or sham injury. Multiple strategies, including MRI with T2-weighted imaging and 18F-FDG PET/CT scanning, were performed to compare the improved and classic SAH models. Results: The new method of filament model resulted a typical pathophysiological progress of early brain injury (EBI), including cerebral oedema, blood brain barrier (BBB) disruption, neuronal apoptosis and microglia activation. The improved SAH model is characterized by a shorter operation time (15.65 ± 0.64 min vs. 21.75 ± 0.94 min), reduced surgically induced injury (decreased 18F-FDG standardized uptake values (SUV): 1.7 ± 0.07 vs. 2.02 ± 0.11), and stable cerebral perfusion before SAH. Conclusions: The improved surgical technique appears to be a feasible tool for experimental and translational studies of SAH.
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Procedimentos Endovasculares/métodos , Hemorragia Subaracnóidea/patologia , Animais , Barreira Hematoencefálica , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hemorragia Subaracnóidea/cirurgiaRESUMO
OBJECTIVE: To evaluate the expression of translocator protein (TSPO) in brain tissue within 72 h after subarachnoid hemorrhage (SAH) in mice. METHODS: Forty-four C57BL/6J mice were randomly divided into two groups, 17 in the Sham group and 27 in the SAH group. SAH mice model was performed by endovascular perforation as previously described with slight modifications. Sham group mice were performed by the same method but without piercing the blood vessels. Before and 6 h, 24 h, 48 h, 72 h after modeling, the two groups were scored with modified Garcia score for neurological function. At 6 h, 24 h, 48 h, 72 h after modeling, the mice were sacrificed. Sham group mice were sacrificed at 24 h after modeling. The expression of TSPO in brain tissue was evaluated by Western blot, positron emission tomography-computed tomography (PET-CT) and immunofluorescence staining. Fluorescent double staining was used to assess the relationship of TSPO and microglia. RESULTS: The neurological function scores of the SAH group mice decreased with time and then increased. The expression of TSPO in the brain tissue increased first and then decreased with time, and there was a negative correlation between them (r=-0.615 6, P < 0.01). PET-CT showed that the tracer intake of mouse brain tissue after SAH was higher than that of Sham group, and the difference was statistically significant (P < 0.05). Immunofluorescence staining showed that TSPO increased in the parietal cortex and basal cortex of the SAH group. And fluorescent double staining suggested that TSPO colocalized with Iba-1 which was a specific marker of microglia. CONCLUSIONS: In the early brain injury after SAH, the expression of TSPO in brain is widely increased, and the expression level increases first and then decreases. TSPO could participate in the activation of microglia and regulate the occurrence and development of brain injury after SAH.
Assuntos
Lesões Encefálicas/metabolismo , Microglia/metabolismo , Receptores de GABA/metabolismo , Hemorragia Subaracnóidea/metabolismo , Animais , Camundongos , Camundongos Endogâmicos C57BL , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Distribuição AleatóriaRESUMO
Based on the Gullstrand I model eye, a simplified model eye for testing fundus imaging device is designed. The model eye can reach the following requirements:(1) The refractive characteristics of the ocular refractive tissue are simulated, and the equivalent focal length in air is 17 mm; (2) The differences between relative refractive index differences of the adjacent materials of the simplified model eye and relative refractive index differences of any adjacent two layers (cornea and aqueous humor, aqueous humor and lens, lens and vitreous body) of the Gullstrand I model eye are not more than 1%; (3) In the case of the incident aperture diameter of 3 mm, the differences of radii of the diffuse spots formed by the paraxial light and the axial light are not more than 15%; (4) The differences of angles of chief ray and tangent line of the fundus are not more than 1°; (5) In the case of the incident aperture diameter of 3 mm, the differences of MTF values of the near axis light are not more than 0.1. The simplified model eye can be expected to be used for testing fundus imaging device instead of the test method in ISO 10940:2009 Ophthalmic instruments-Fundus cameras.
Assuntos
Cristalino , Refração Ocular , Córnea , Fundo de Olho , Cristalino/diagnóstico por imagemRESUMO
ß-Caryophyllene (BCP) mediates neuroprotection in cerebral ischemic animals. The neurovascular unit (NVU) acts as an intricate network to maintain the neuronal homeostatic microenvironment. However, the effects exerted by BCP on NVU remain unclear. Therefore, we established an in vitro NVU model to investigate the effects of BCP on oxygen-glucose deprivation and re-oxygenation (OGD/R)-induced injury. This model involved the co-culture of brain microvascular endothelial cells, neurons, and astrocytes. BCP (10 µmol/L) was applied for 24 h prior to OGD/R and maintained throughout OGD/R. Blood-brain barrier (BBB) integrity and neuronal apoptosis were analyzed. BCP pre-treatment prior to the initiation of OGD/R significantly (i) decreased BBB permeability and neuronal apoptosis, (ii) mitigated oxidative stress damage and the release of inflammatory cytokines, (iii) down-regulated Bax expression, metalloproteinase-9 activity and expression, and (iv) up-regulated claudin-5, occludin, ZO-1, growth-associated protein-43 and Bcl-2 expression. Thus, BCP pre-treatment exerted multiple protective effects on NVU in the context of OGD/R-induced injury. These protective effects potentially occur via reductions in oxidative stress damage and inflammatory cytokines that induce BBB breakdown, subsequently resulting in reduced neuronal apoptosis. The NVU serves as putative therapeutic targets for cerebral ischemia, and the results of this study provide new insights for the application of BCP as a neuroprotective agent.