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1.
Glia ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056459

RESUMO

Triggering receptor expressed on myeloid cells 2 (TREM2) has been shown to confer strong neuroprotective effects in acute ischemic stroke (AIS). However, as the vast majority of research findings to date are based on its functions in microglia, the precise role of TREM2 in astrocytes after AIS is unknown. Here, both loss- and gain-of-function experiments were employed to investigate how astrocytic TREM2 influences the pathogenesis of AIS in vivo and in vitro. Our results demonstrated that cerebral ischemia triggered induction of TREM2 expression on reactive astrocytes following AIS. In addition, astrocyte-specific TREM2 knockout mice exhibited much greater brain injury than TREM2 flox/flox controls following AIS, as evidenced by increased cerebral infarct volume, neuronal apoptosis and neurological deficit, which was associated with an increased expression of pro-inflammatory molecule complement component 3 (C3) on reactive astrocytes and activation of microglia/macrophages but decreased expression of S100 calcium binding protein A10 (S100A10) and arginase1 (Arg1) on reactive astrocytes. Mechanistic analyses revealed that astrocytic TREM2 alleviated brain injury by inhibiting detrimental actions of reactive astrocytes but promoting their neuro- and glioprotective actions via the kruppel-like transcription factor-4-nuclear factor-κB axis. Together, this study provides novel evidence for a critical protective role of astrocyte-derived TREM2 in AIS and highlights a potential therapeutic target for the treatment of AIS.

2.
Anal Bioanal Chem ; 416(22): 4873-4885, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38951148

RESUMO

Ferroptosis is a way of cell death mainly due to the imbalance between the production and degradation of lipid reactive oxygen species, which is closely associated with various diseases. Endogenous hypochlorous acid (HOCl) mainly produced in mitochondria is regarded as an important signal molecule of ferroptosis. Therefore, monitoring the fluctuation of endogenous HOCl is beneficial to better understand and treat ferroptosis-related diseases. Inspired by the promising aggregation-induced emission (AIE) properties of tetraphenylethene (TPE), herein, we rationally constructed a novel AIE-based fluorescent probe, namely QTrPEP, for HOCl with nice mitochondria-targeting ability and high sensitivity and selectivity. Probe QTrPEP consisted of phenylborate ester and the AIE fluorophore of quinoline-conjugated triphenylethylene (QTrPE). HOCl can brighten the strong fluorescence through a specific HOCl-triggered cleavage of the phenylborate ester bond and release of QTrPE, which has been demonstrated by MS, HPLC, and DLS experiments. In addition, combining QTrPE-doped test strips with a smartphone-based measurement demonstrated the excellent performance of the probe to sense HOCl. The obtained favorable optical properties and negligible cytotoxicity allowed the use of this probe for tracking of HOCl in three different cells. In particular, this work represents the first AIE-based mitochondria-targeting fluorescent probe for monitoring the fluctuation of HOCl in ferroptosis.


Assuntos
Ferroptose , Corantes Fluorescentes , Ácido Hipocloroso , Mitocôndrias , Ácido Hipocloroso/análise , Ácido Hipocloroso/metabolismo , Corantes Fluorescentes/química , Mitocôndrias/metabolismo , Ferroptose/efeitos dos fármacos , Humanos , Espectrometria de Fluorescência/métodos , Imagem Óptica/métodos
3.
J Neuroinflammation ; 20(1): 44, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823628

RESUMO

BACKGROUND: We have previously demonstrated that the expression of kruppel-like transcription factor-4 (KLF-4) is upregulated in astrocytes following acute ischemic stroke (AIS) and found that KLF4 confers vascular protection against cerebral ischemic injury. However, the functional role of KLF4 in astrocyte after AIS is far from clear. METHODS: The intrinsic relationship between KLF4 and A1/A2 reactive astrocytes and the impact of astrocytic KLF4 on the activation of A1/A2 subtype astrocytes were evaluated in middle cerebral artery occlusion (MCAO) mice and oxygen-glucose deprivation and restoration (OGD/R) astrocytes. RESULTS: Our results demonstrated that astrocytic KLF4 expression and complement C3-positive A1 and S100 calcium binding protein A10 (S100A10)-positive A2 astrocytes were induced in the ischemic penumbra following focal cerebral ischemia, and the time course of upregulation of astrocytic KLF4 correlated closely with the activation of A2 astrocytes. The dual immunofluorescent studies displayed that in the ischemic hemisphere, where the high levels of KLF4 were expressed, there were relatively low levels of C3 expressed in the reactive astrocytes and vice versa, but KLF4 was always co-stained well with S100A10. Mechanistic analyses revealed that astrocytic KLF4 inhibited the activation of A1 astrocyte but promoted A2 astrocyte polarization after OGD/R by modulating expressions of nuclear factor-kB. CONCLUSIONS: Astrocyte-derived KLF4 has a critical role in regulating the activation of A1/A2 reactive astrocytes following AIS.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Fator 4 Semelhante a Kruppel , Acidente Vascular Cerebral , Animais , Camundongos , Astrócitos/metabolismo , Isquemia Encefálica/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , AVC Isquêmico/metabolismo , Oxigênio/metabolismo , Acidente Vascular Cerebral/metabolismo , Fator 4 Semelhante a Kruppel/metabolismo
4.
Pharmacol Res ; 165: 105444, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33493657

RESUMO

With the development of high-throughput screening and bioinformatics technology, natural products with a range of pharmacological targets in multiple diseases have become important sources of new drug discovery. These compounds are derived from various plants, including the dried root of Scutellaria baicalensis Georgi, which is often used as a traditional Chinese herb named Huangqin, a popular medication used for thousands of years in China. Many studies have shown that baicalin, an extract from Scutellaria baicalensis Georgi, exerts various protective effects on liver and gut diseases. Baicalin plays a therapeutic role mainly by mediating downstream apoptosis and immune response pathways induced by upstream oxidative stress and inflammation. During oxidative stress regulation, PI3K/Akt/NRF2, Keap-1, NF-κB and HO-1 are key factors associated with the healing effects of baicalin on NAFLD/NASH, ulcerative colitis and cholestasis. In the inflammatory response, IL-6, IL-1ß, TNF-α, MIP-2 and MIP-1α are involved in the alleviation of NAFLD/NASH, cholestasis and liver fibrosis by baicalin, as are TGF-ß1/Smads, STAT3 and NF-κB. Regarding the apoptosis pathway, Bax, Bcl-2, Caspase-3 and Caspase-9 are key factors related to the suppression of hepatocellular carcinoma and attenuation of liver injury and colorectal cancer. In addition to immune regulation, PD-1/PDL-1 and TLR4-NF-κB are correlated with the alleviation of hepatocellular carcinoma, ulcerative colitis and colorectal cancer by baicalin. Moreover, baicalin regulates intestinal flora by promoting the production of SCFAs. Furthermore, BA is involved in the interactions of the liver-gut axis by regulating TGR5, FXR, bile acids and the microbiota. In general, a comprehensive analysis of this natural compound was conducted to determine the mechanism by which it regulates bile acid metabolism, the intestinal flora and related signaling pathways, providing new insights into the pharmacological effects of baicalin. The mechanism linking the liver and gut systems needs to be elucidated to draw attention to its great clinical importance.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Flavonoides/farmacologia , Trato Gastrointestinal/efeitos dos fármacos , Mediadores da Inflamação/antagonistas & inibidores , Fígado/efeitos dos fármacos , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Flavonoides/uso terapêutico , Trato Gastrointestinal/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Fígado/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
5.
Cell Biol Int ; 45(11): 2287-2293, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34363272

RESUMO

Myasthenia gravis (MG) is a disease involving neuromuscular transmission that causes fatigue of skeletal muscles and fluctuating weakness. It has been shown that impairment of myogenic differentiation and myofiber maturation may be the underlying cause of MG. In this study, we detected the abnormal expression of circular RNA (circRNA) using next-generation sequencing in patients with MG. We then investigated the regulatory mechanism and the relationship among circRNA, microRNA, and messenger RNA using quantitative reverse-transcription polymerase chain reaction, bioinformatics analysis, and luciferase report analysis. The expression of inflammatory cytokines and regulatory T lymphocytes was shown to be increased. Circ-FBL was significantly increased in MG patients. Bioinformatics and luciferase report analyses confirmed that miR-133 and PAX7 were the downstream targets of circ-FBL. Overexpression of circ-FBL promoted myoblast proliferation by regulation of miR-133/PAX7. Taken together, our study showed that upregulation of circ-FBL promoted myogenic proliferation in patients with MG by regulating miR-133/PAX7.


Assuntos
MicroRNAs/genética , Miastenia Gravis/genética , Fator de Transcrição PAX7/genética , Animais , Apoptose/genética , Diferenciação Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Desenvolvimento Muscular/genética , Miastenia Gravis/metabolismo , Fator de Transcrição PAX7/metabolismo , RNA Circular/genética , RNA Mensageiro
6.
EMBO J ; 35(13): 1368-84, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27145933

RESUMO

In hypoxic cells, dysfunctional mitochondria are selectively removed by a specialized autophagic process called mitophagy. The ER-mitochondrial contact site (MAM) is essential for fission of mitochondria prior to engulfment, and the outer mitochondrial membrane protein FUNDC1 interacts with LC3 to recruit autophagosomes, but the mechanisms integrating these processes are poorly understood. Here, we describe a new pathway mediating mitochondrial fission and subsequent mitophagy under hypoxic conditions. FUNDC1 accumulates at the MAM by associating with the ER membrane protein calnexin. As mitophagy proceeds, FUNDC1/calnexin association attenuates and the exposed cytosolic loop of FUNDC1 interacts with DRP1 instead. DRP1 is thereby recruited to the MAM, and mitochondrial fission then occurs. Knockdown of FUNDC1, DRP1, or calnexin prevents fission and mitophagy under hypoxic conditions. Thus, FUNDC1 integrates mitochondrial fission and mitophagy at the interface of the MAM by working in concert with DRP1 and calnexin under hypoxic conditions in mammalian cells.


Assuntos
Calnexina/metabolismo , Retículo Endoplasmático/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Hipóxia , Proteínas de Membrana/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Dinâmica Mitocondrial , Proteínas Mitocondriais/metabolismo , Células Cultivadas , Dinaminas , Humanos , Mitofagia , Ligação Proteica
7.
J Neuroinflammation ; 17(1): 107, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32264912

RESUMO

BACKGROUND: Although inflammatory cell adhesion molecules (CAMs) and anti-inflammation factor Kruppel-like transcription factor (KLF) 4 have all been reported to be induced after cerebral ischemic stroke (CIS), the close temporal and spatial relationship between expressions of CAMs and KLF4 following CIS and whether and how CAMs and KLF-4 contribute to the development of CIS-induced vascular injury are still unclear. METHODS: Here, we first examined the correlation between serum levels of CAMs/KLF4 and infarct volume in acute CIS patients. Then, we determined the relationship between CAMs and KLF4 in mice after focal cerebral ischemia. Finally, we investigated the mechanism of KLF4 in protecting against oxygen-glucose deprivation-induced brain endothelial cell injury. RESULTS: Our results demonstrated that patients with moderate to severe CIS had higher serum levels of three CAMs including E-selectin, inter-cellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1) but lower levels of KLF4 at 48 h after an acute event as compared to patients with minor CIS. The expression levels of three CAMs as well as KLF4 all correlated well with the infarct volume in all the CIS subjects at that time. Although the expressions of three CAMs and KLF4 were all induced in the ischemic hemisphere following focal cerebral ischemia, the peak timing and distribution patterns of their expression were different: the induction of KLF4 lagged behind that of the CAMs in the ischemic penumbra; furthermore, the dual immunofluorescent studies displayed that high expression of KLF4 was always associated with relatively less cerebral vascular endothelial inflammation response in the ischemic hemisphere and vice versa. Mechanistic analyses revealed that KLF4 alleviated CIS-induced cerebral vascular injury by regulating endothelial expressions of CAMs, nuclear factor-kB, and tight junction proteins. CONCLUSIONS: These data indicate that KLF4 confers vascular protection against cerebral ischemic injury, suggesting that circulating CAMs and KLF4 might be used as potential biomarkers for predicting the prognosis of acute ischemic stroke and also providing a new proof of concept and potential targets for future prevention and treatment of CIS.


Assuntos
Células Endoteliais/patologia , Inflamação/patologia , AVC Isquêmico/patologia , Fatores de Transcrição Kruppel-Like/metabolismo , Animais , Moléculas de Adesão Celular/metabolismo , Humanos , Inflamação/metabolismo , AVC Isquêmico/metabolismo , Fator 4 Semelhante a Kruppel , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Junções Íntimas/metabolismo
8.
Cell Physiol Biochem ; 47(2): 864-878, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29807362

RESUMO

BACKGROUND/AIMS: Recent studies have indicated that exosomes secreted from adipose-derived stem cells (ADSCs) have important effects in the treatment of ischemic injury. However, the treatment mechanism is unclear. This study aimed to investigate whether ADSC-derived exosomes enriched with microRNA (miR)-30d-5p have a protective effect on acute ischemic stroke (AIS). METHODS: In the current study, inflammatory factors and miR-30d-5p expression were assessed in 70 subjects with AIS and 35 healthy controls. Exosomes were characterized by transmission electron microscopy and further examined using nanoparticle tracking analyses. A rat model of AIS and an in vitro model of oxygen- and glucose-deprived (OGD) primary microglia were established to study the protective mechanism of exosomes from miR-30d-5p-overexpressing ADSCs in ischemia-induced nerve injury. RESULTS: The results showed that following AIS, the expression of inflammatory cytokines increased, while the anti-inflammatory cytokines IL-4, IL-10, and miR-30d-5p decreased both in patients and in animal models. Moreover, in vitro studies demonstrated that suppression of autophagy significantly reduced the OGD-induced inflammatory response. In addition, exosome treatment was more effective in suppressing the inflammatory response by reversing OGD-induced and autophagy-mediated microglial polarization to M1. Furthermore, in vivo studies showed that exosomes derived from ADSCs significantly decreased the cerebral injury area of infarction by suppressing autophagy and promoting M2 microglia/macrophage polarization. CONCLUSIONS: Our results suggest that miR-30d-5p-enhanced ADSC-derived exosomes prevent cerebral injury by inhibiting autophagy-mediated microglial polarization to M1.


Assuntos
Autofagia , Exossomos/metabolismo , MicroRNAs/metabolismo , Acidente Vascular Cerebral/patologia , Tecido Adiposo/citologia , Idoso , Animais , Proteína 5 Relacionada à Autofagia/química , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Citocinas/sangue , Feminino , Humanos , Macrófagos/citologia , Macrófagos/metabolismo , Masculino , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Microglia/citologia , Microglia/metabolismo , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley , Células-Tronco/citologia , Células-Tronco/metabolismo , Acidente Vascular Cerebral/metabolismo
9.
Biochem Biophys Res Commun ; 499(4): 758-764, 2018 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-29605297

RESUMO

Circular RNAs (circRNAs) are highly expressed in eukaryotic cells and regulate physiological and pathophysiological processes. However, the role of circRNAs in cerebral ischemia-reperfusion (I/R) injury remains largely unknown. In this study, we found that circ_008018 level was higher in the cortical tissue of mice with middle cerebral artery occlusion as compared to those in the sham group 24 h after reperfusion. Knockdown of circ_008018 attenuated cerebral I/R-induced brain tissue damage and neurological deficits in mice by inducing microRNA miR-99a overexpression. The decreased phosphorylation of Akt and glycogen synthase kinase 3ß caused by I/R was partly reversed by circ_008018 silencing or miR-99a overexpression. Taken together, these results provide new insight into the mechanisms of apoptosis resulting from cerebral I/R injury and suggest that targeted inhibition of circ_008018 can protect against subsequent neurological damage.


Assuntos
Isquemia Encefálica/genética , Isquemia Encefálica/prevenção & controle , Regulação para Baixo/genética , MicroRNAs/metabolismo , RNA/genética , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/prevenção & controle , Animais , Sequência de Bases , Isquemia Encefálica/patologia , Inativação Gênica , Glicogênio Sintase Quinase 3 beta/genética , Masculino , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA/metabolismo , RNA Circular , Traumatismo por Reperfusão/patologia , Transdução de Sinais
10.
Lipids Health Dis ; 16(1): 213, 2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29132372

RESUMO

BACKGROUND: Hepatitis B virus (HBV) infection in the body can damage liver cells and cause disorders in blood lipid metabolism. Apolipoprotein C3 (ApoC3) plays an important role in the regulation of lipid metabolism, but no study on the HBV regulation of ApoC3 has been reported. This purpose of this study was to investigate the effect of HBV on ApoC3 expression and its regulatory mechanism. METHODS: The expression levels of ApoC3 mRNA and protein in the human hepatoma cell lines HepG2 and HepG2.2.15 were determined using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blot. The HepG2 cells were co-transfected with the ApoC3 gene promoter and either HBV-infected clone pHBV1.3 or its individual genes. The changes in luciferase activity were assayed. The expression levels of ApoC3 mRNA and protein were determined using RT-qPCR and Western blot. The content of ApoC3 in the supernatant of the cultured cells was determined using an enzyme-linked immunosorbent assay (ELISA). The sera were collected from 149 patients with HBV infection and 102 healthy subjects at physical examination as the normal controls. The serological levels of ApoC3 in the HBV group and the normal control group were determined using ELISA. The contents of serum triglyceride (TG) and very-low-density lipoprotein (VLDL) in the HBV patients and the normal control were determined using an automatic biochemical analyser. RESULTS: The expression levels of ApoC3 mRNA and protein were lower in the HepG2.2.15 cells than in the HepG2 cells. pHBV1.3 and its X gene could inhibit the activity of the ApoC3 promoter and its mRNA and protein expression. The serum levels of ApoC3, VLDL and TG were 65.39 ± 7.48 µg/ml, 1.24 ± 0.49 mmol/L, and 0.46 ± 0.10 mmol/L in the HBV patients and 41.02 ± 6.88 µg/ml, 0.76 ± 0.21 mmol/L, 0.29 ± 0.05 mmol/L in the normal controls, respectively, statistical analysis revealed significantly lower serum levels of ApoC3, VLDL and TG in HBV patients than in the normal controls (P < 0.05). CONCLUSION: HBV can inhibit the in vivo and in vitro synthesis and secretion of ApoC3.


Assuntos
Apolipoproteína C-III/biossíntese , Hepatite B/sangue , Hepatócitos/virologia , Lipoproteínas VLDL/sangue , Adulto , Apolipoproteína C-III/genética , Apolipoproteína C-III/metabolismo , Feminino , Regulação da Expressão Gênica , Células Hep G2 , Vírus da Hepatite B , Hepatócitos/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade
11.
Eur Neurol ; 77(1-2): 25-31, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27846637

RESUMO

BACKGROUND: Atherosclerosis is a complicated disease governed by genetic, environmental and vascular risk factors, while its relationship with specific genes is still unclear. In recent days, it has been discovered that the single-nucleotide polymorphisms of chromosomal region 9p21 were relevant with the genetic susceptibility of Atherosclerosis. We aimed to figure out the relativity between the gene polymorphism of region 9p21 (rs10757274, rs7044859, rs4977574 and rs496892) and carotid plaque. METHODS: With polymerase chain reaction-ligase detection reaction, the gene polymorphisms of site rs10757274, rs7044859, rs4977574 and rs496892 in chromosome region 9p21 were analyzed in 764 non-cardiac cerebral infarction (CI) patients (406 with carotid plaque while 358 without). RESULTS: Among the population aged between 45 and 65, compared to patients without carotid plaque, no significant difference were observed on the genotype or allele frequencies distribution in 9p21 genes including rs10757274, rs7044859, rs4977574 and rs496892 in the patients with carotid plaque. There existed strong linkage disequilibrium not only between rs10757274 and rs4977574 but also between rs7044859 and rs496892 as well. CONCLUSION: In Chinese Han CI population, there was no significant relevance between the polymorphisms of site rs10757274, rs7044859, rs4977574 and rs496892 in region 9p21 and the susceptibility of carotid plaque.


Assuntos
Estenose das Carótidas/genética , Cromossomos Humanos Par 9/genética , Predisposição Genética para Doença/genética , Idoso , Povo Asiático/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Fatores de Risco
12.
J Neuroinflammation ; 13(1): 227, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27586239

RESUMO

BACKGROUND: The pro-inflammatory cytokine, tumor necrosis factor-α (TNF-α), is expressed in ischemic tissue and is known to modulate angiogenesis; however, the role of the two distinct TNF-α receptors, TNFR1 and TNFR2, in mediating angiogenic signaling after cerebral ischemic stroke is relatively unknown. METHODS: C57BL6 mice were subject to 90 min of ischemia by temporary occlusion of the middle cerebral artery (MCAO) and given daily intra-cerebroventricular injections of antibodies against TNFR1, TNFR2 or control IgG (doses of 10, 50, and 100 ng/day) for 4 days following 90 min MCAO. Vascular remodeling and α5ß1 and αVß3 integrin expression were then examined in the brains of these mice after 4, 7, and 14 days post-ischemia. In parallel in vitro studies, flow cytometry was used to determine the influence of TNF-α on proliferation and integrin expression of human brain microvascular endothelial cells (HBMECs). RESULTS: The post-ischemic cerebral angiogenic response was inhibited by antibodies against TNFR1 but not TNFR2, and this correlated with reduced endothelial proliferation and decreased α5ß1 and αVß3 integrin expression after 4 and 7 days post-ischemia. Consistent with these findings, in vitro studies showed that TNF-α induced endothelial proliferation and upregulation of α5ß1 and αVß3 integrins was abrogated by anti-TNFR1 but not anti-TNFR2 antibodies in cultured HBMECs. In addition, blocking antibodies to α5ß1 and αVß3 integrins significantly inhibited TNF-α-induced HBMEC proliferation. CONCLUSIONS: Our results suggest that TNFR1-mediated signaling plays a critical role in triggering angiogenic integrins and subsequent angiogenic responses following cerebral ischemia. These novel findings could form a platform for future therapeutic strategies aimed at stimulating angiogenesis following cerebral ischemia.


Assuntos
Anticorpos/farmacologia , Integrina alfa5beta1/metabolismo , Integrina alfaVbeta3/metabolismo , Neovascularização Patológica/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Encéfalo/citologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Infarto da Artéria Cerebral Média/complicações , Integrina alfa5beta1/imunologia , Integrina alfaVbeta3/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/etiologia , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Receptores Tipo II do Fator de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos
13.
EMBO Rep ; 15(5): 566-75, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24671035

RESUMO

Autophagy eliminates dysfunctional mitochondria in an intricate process known as mitophagy. ULK1 is critical for the induction of autophagy, but its substrate(s) and mechanism of action in mitophagy remain unclear. Here, we show that ULK1 is upregulated and translocates to fragmented mitochondria upon mitophagy induction by either hypoxia or mitochondrial uncouplers. At mitochondria, ULK1 interacts with FUNDC1, phosphorylating it at serine 17, which enhances FUNDC1 binding to LC3. A ULK1-binding-deficient mutant of FUNDC1 prevents ULK1 translocation to mitochondria and inhibits mitophagy. Finally, kinase-active ULK1 and a phospho-mimicking mutant of FUNDC1 rescue mitophagy in ULK1-null cells. Thus, we conclude that FUNDC1 regulates ULK1 recruitment to damaged mitochondria, where FUNDC1 phosphorylation by ULK1 is crucial for mitophagy.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Mitofagia/fisiologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Hipóxia Celular , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Proteínas de Membrana/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/fisiologia , Proteínas Mitocondriais/genética , Mutação , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/biossíntese , Regulação para Cima
14.
J Biol Chem ; 289(15): 10691-10701, 2014 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-24573672

RESUMO

Mitophagy receptors mediate the selective recognition and targeting of damaged mitochondria by autophagosomes. The mechanism for the regulation of these receptors remains unknown. Here, we demonstrated that a novel hypoxia-responsive microRNA, microRNA-137 (miR-137), markedly inhibits mitochondrial degradation by autophagy without affecting global autophagy. miR-137 targets the expression of two mitophagy receptors NIX and FUNDC1. Impaired mitophagy in response to hypoxia caused by miR-137 is reversed by re-expression of FUNDC1 and NIX expression vectors lacking the miR-137 recognition sites at their 3' UTR. Conversely, miR-137 also suppresses the mitophagy induced by fundc1 (CDS+3'UTR) but not fundc1 (CDS) overexpression. Finally, we found that miR-137 inhibits mitophagy by reducing the expression of the mitophagy receptor thereby leads to inadequate interaction between mitophagy receptor and LC3. Our results demonstrated the regulatory role of miRNA to mitophagy receptors and revealed a novel link between miR-137 and mitophagy.


Assuntos
Autofagia , Proteínas de Membrana/metabolismo , MicroRNAs/metabolismo , Proteínas Mitocondriais/metabolismo , Regiões 3' não Traduzidas , Animais , Hipóxia Celular , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Vetores Genéticos , Células HEK293 , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Fagossomos/metabolismo
15.
J Photochem Photobiol B ; 258: 112995, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39096720

RESUMO

Endogenous hypochlorous acid (HOCl) is one of the most important reactive oxygen species (ROS) and acts as a distinct biomarker that is involved in various inflammatory responses including rheumatoid arthritis (RA). Therefore, it's crucial to develop an efficient method for the tracking and analysis of HOCl levels in vivo. Natural products continue to be compounds of interest, because they not only offer diverse and specific molecular scaffolds but also provide invaluable sources for new drug discovery. Herein, we firstly demonstrated harmaline (HML), a natural alkaloid mainly found in Peganum harmala L, could be acted as a novel fluorescent probe for HOCl with exceptional precision and responsiveness. Remarkably, this probe not only specifically tracked HOCl levels in cells and inflammatory RA mouse models, but also exhibited effective anti-inflammatory effects on RAW264.7 cells and anti-proliferative effects on fibroblast-like synoviocytes. Furthermore, HML has the potential to alleviate LPS-induced inflammation by inhibiting the NF-κB signaling pathway. This study represents the first example of a natural product that can simultaneously act as a fluorescent probe for specific ROS and a promising therapeutic candidate for a specific disease, which will undoubtedly extend the application of fluorophore-rich natural products.


Assuntos
Artrite Reumatoide , Corantes Fluorescentes , Harmalina , Ácido Hipocloroso , Animais , Ácido Hipocloroso/metabolismo , Camundongos , Corantes Fluorescentes/química , Artrite Reumatoide/tratamento farmacológico , Células RAW 264.7 , Harmalina/química , Harmalina/farmacologia , NF-kappa B/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sinoviócitos/efeitos dos fármacos , Sinoviócitos/metabolismo , Proliferação de Células/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Humanos , Peganum/química
16.
Food Chem ; 456: 140064, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38878548

RESUMO

Cysteine (Cys) not only plays an indispensable role in maintaining the redox balance in organisms, but is also an important nutrient in the food industry. Fluorescence-based detection systems have emerged as an effective method to track the locations and concentrations of different species. To achieve efficient monitoring of Cys in both food samples and biological systems, a novel lipid droplet (LD) targeted fluorescent probe (namely NIT-Cys) was constructed for the turn-on detection of Cys, characterized by a large Stokes shift (142 nm), a short response time (<8 min), and a low Cys detection limit (39 nM). Furthermore, the NIT-Cys probe has been successfully used not only to quantify the amounts of Cys in selected food samples, but also to enable the visualization of endogenous Cys in acetaminophen (APAP)-induced drug-induced liver injury cells, zebrafish larvae and mice models. Consequently, the work presented here provides an efficient tool for monitoring Cys.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Cisteína , Corantes Fluorescentes , Análise de Alimentos , Peixe-Zebra , Corantes Fluorescentes/química , Animais , Cisteína/análise , Cisteína/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Camundongos , Humanos , Fígado/química , Fígado/metabolismo
17.
J Hazard Mater ; 480: 136059, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39369680

RESUMO

Mercury ions (Hg2+) and mercury derivatives are a serious threat to ecosystems and human health due to their toxicity, and their toxicological effects are associated with a burst of reactive oxygen species (ROS) due to the oxidative stress. Endogenous hydrogen peroxide (H2O2), a featured ROS in vivo, plays an irreplaceable role in a significant number of pathological processes. However, the exact bioeffect role that H2O2 plays in Hg2+-induced oxidative stress in a specific disease has not been well answered. In particular, optical imaging probes for H2O2 endowed with afterglow emission properties are very rare. Here, the first fluorescence/afterglow probe (FA-H2O2) for accurate and specific detection of H2O2 in cells, zebrafish, and mice under Hg2+-induced oxidative stress is reported. Moreover, FA-H2O2 in its afterglow emission enables efficient monitoring of endogenous H2O2 with a higher signal-to-noise ratio (SNR) in comparison to its fluorescence signals. More importantly, by virtue of the merits of afterglow emission that can eliminate autofluorescence, thus for the first time, shortening the diagnostic window of Hg2+-induced liver injury with FA-H2O2 via noninvasive afterglow emission tracking of H2O2 is achieved, which definitely provides a new opportunity and promising tool for early diagnosis of Hg2+-induced liver injury.

18.
World Neurosurg ; 173: e329-e340, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36796629

RESUMO

BACKGROUND: Moyamoya disease (MMD) is a rare cerebrovascular disease in neurology. This study investigates the literature related to MMD from its discovery to the present and identifies research levels, achievements, and trends. METHODS: All publications on MMD from its discovery to present were downloaded from the Web of Science Core Collection on September 15, 2022 and bibliometric analyses were visualized by HistCite Pro, VOSviewer, Scimago Graphica, CiteSpace, and R language. RESULTS: There were 3414 articles in 680 journals by 10,522 authors in 2441 institutions and 74 countries/regions worldwise are included in the analyses. Since the discovery of MMD, output of publications has shown an upward trend. Japan, the United States, China, and South Korea are 4 major countries in MMD. The United States has the strongest cooperation with other countries. China's Capital Medical University is the output-leading institution worldwide, followed by Seoul National University and Tohoku University. The 3 authors with the most published articles are Kiyohiro Houkin, Dong Zhang, and Satoshi Kuroda. World Neurosurgery, Neurosurgery, and Stroke are the most recognized journals for researchers. Hemorrhagic moyamoya disease, susceptibility gene, and arterial spin are the primary focus areas of MMD research. "Rnf213,""vascular disorder," and "progress" are the top keywords. CONCLUSIONS: We analyzed publications of global scientific research on MMD systematically by bibliometric methods. This study can provide one of the most comprehensive and accurate analyses for MMD scholars worldwide.


Assuntos
Doença de Moyamoya , Humanos , Estados Unidos , Bibliometria , Publicações , China , Adenosina Trifosfatases , Ubiquitina-Proteína Ligases
19.
Anal Chim Acta ; 1279: 341819, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37827641

RESUMO

Cysteine (Cys), one of essential small-molecule-based biothiols in the human body, contributes to the regulation of redox reactions and is closely associated with many physiological and pathological metabolic processes. Herein, a novel fluorescent probe, hydroxyphenyl-conjugated benzothiazole (HBT-Cys) capable of detecting Cys was constructed, where acrylate served as the recognition group and hydroxyphenyl-linked benzothiazole acted as the fluorophore. The fluorescence of the probe was negligible in the absence of Cys, and an intense blue fluorescence was observed upon addition of Cys. The Cys-sensing mechanism could be ascribed to the Cys-involved hydrolysis reaction with acrylate, leading to light up the emission at 430 nm with about 80-fold enhancement. In addition, HBT-Cys exhibited a fast response time, remarkable selectivity and low detection limit. HBT-Cys also worked well in real-time monitoring of Cys in three different food samples (wolfberry, hawthorn, and red dates). Importantly, our probe had an excellent lysosomes-targeted ability, which was successfully employed to real-time visualize the fluctuation of both exogenous and endogenous Cys in living cells and zebrafish under lipopolysaccharide (LPS)-induced oxidative stress. Hopefully, the work shown here provides a potent candidate for the real-time tracking of Cys fluctuations in various biological samples.


Assuntos
Cisteína , Corantes Fluorescentes , Animais , Humanos , Corantes Fluorescentes/metabolismo , Cisteína/metabolismo , Lipopolissacarídeos/farmacologia , Células HeLa , Peixe-Zebra , Lisossomos/metabolismo , Estresse Oxidativo , Acrilatos , Benzotiazóis/metabolismo , Glutationa/metabolismo
20.
Clin Exp Pharmacol Physiol ; 39(5): 447-53, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22360610

RESUMO

Propofol (2,6-diisopropylphenol) is an anaesthetic agent with anti-oxidant properties. The aim of the present study was to determine whether propofol can protect pulmonary epithelial (A549) cells against lipopolysaccharide (LPS)-induced cell death and, if so, the mechanisms involved. The effects of LPS alone and in combination with propofol on A549 cell death were investigated. Cell viability was determined using the colourimetric 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Apoptotic A549 cells were detected by flow cytometry, as propidium iodide-negative and annexin-V-positive cells, and terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL). Mitochondrial membrane potential (MMP), caspase 9 activity, Ca(2+) concentrations and reactive oxygen species (ROS) were analysed by immunofluorescent methods. Aconitase 2 (ACO2), microtubule-associated light chain 3 (LC3) and beclin-1 levels were evaluated using reverse transcription-polymerase chain reaction and/or western blot analysis. Exposure of A549 cells to 1-50 µg/mL LPS for 3-24 h resulted in the concentration- and time-dependent induction of cell death. Cell apoptosis accounted for approximately 77% of cell death induced by LPS. Propofol (5-150 µmol/L) concentration-dependently inhibited LPS-induced A549 cell death. This protective effect of propofol was accompanied by prevention of LPS-induced mitochondrial dysfunction (reductions in MMP, ACO2 expression and ATP) and was associated with the inhibition of LPS-induced activation of apoptotic signals (caspase 9 activity, ROS overproduction and Ca(2+) accumulation). In addition, propofol blocked LPS-induced overexpression of the autophagy-associated proteins LC3 and beclin-1. The data indicate that propofol protects A549 cells against LPS-induced apoptosis, and probably autophagy, by blocking LPS-induced activation of ROS/caspase 9 pathways and upregulation of LC3 and beclin-1, respectively.


Assuntos
Células Epiteliais/efeitos dos fármacos , Lipopolissacarídeos/antagonistas & inibidores , Lipopolissacarídeos/toxicidade , Propofol/farmacologia , Mucosa Respiratória/efeitos dos fármacos , Anestésicos Intravenosos , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Citoproteção/efeitos dos fármacos , Citoproteção/fisiologia , Células Epiteliais/fisiologia , Humanos , Pulmão/citologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Propofol/uso terapêutico , Mucosa Respiratória/citologia , Mucosa Respiratória/fisiologia
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