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1.
J Cereb Blood Flow Metab ; : 271678X241248907, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661094

RESUMO

Blood-brain barrier (BBB) disruption is increasingly recognized as an early contributor to the pathophysiology of cerebral ischemia/reperfusion (I/R) injury, and is also a key event in triggering secondary damage to the central nervous system. Recently, long non-coding RNA (lncRNA) have been found to be associated with ischemic stroke. However, the roles of lncRNA in BBB homeostasis remain largely unknown. Here, we report that long intergenic non-coding RNA-p21 (lincRNA-p21) was the most significantly down-regulated lncRNA in human brain microvascular endothelial cells (HBMECs) after oxygen and glucose deprivation/reoxygenation (OGD/R) treatment among candidate lncRNA, which were both sensitive to hypoxia and involved in atherosclerosis. Exogenous brain-endothelium-specific overexpression of lincRNA-p21 could alleviate BBB disruption, diminish infarction volume and attenuate motor function deficits in middle cerebral artery occlusion/reperfusion (MCAO/R) mice. Further results showed that lincRNA-p21 was critical to maintain BBB integrity by inhibiting the degradation of junction proteins under MCAO/R and OGD/R conditions. Specifically, lincRNA-p21 could inhibit autophagy-dependent degradation of occludin by activating PI3K/AKT/mTOR signaling pathway. Besides, lincRNA-p21 could inhibit VE-cadherin degradation by binding with miR-101-3p. Together, we identify that lincRNA-p21 is critical for BBB integrity maintenance, and endothelial lincRNA-p21 overexpression could alleviate cerebral I/R injury in mice, pointing to a potential strategy to treat cerebral I/R injury.

2.
Mol Biol Cell ; 35(4): ar54, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38446615

RESUMO

Proper formation of the hippocampus is crucial for the brain to execute memory and learning functions. However, many questions remain regarding how pyramidal neurons (PNs) of the hippocampus mature and precisely position. Here we revealed that Setd2, the methyltransferase for histone 3 lysine 36 trimethylation (H3K36me3), is essential for the precise localization and maturation of PNs in the hippocampal CA1. The ablation of Setd2 in neural progenitors leads to irregular lamination of the CA1 and increased numbers of PNs in the stratum oriens. Setd2 deletion in postmitotic neurons causes mislocalization and immaturity of CA1 PNs. Transcriptome analyses revealed that SETD2 maintains the expressions of clustered protocadherin (cPcdh) genes. Together, Setd2 is required for proper hippocampal lamination and maturation of CA1 PNs.


Assuntos
Hipocampo , Histonas , Histona Metiltransferases/metabolismo , Histonas/metabolismo , Hipocampo/metabolismo
3.
Int J Biol Macromol ; 261(Pt 1): 129670, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38280697

RESUMO

The oxidative microenvironment in fibrotic livers often diminishes the effectiveness of mesenchymal stem cells (MSCs)-based therapy. Recent research suggests that pharmacological pre-treatment could enhance the therapeutic performance of MSCs. In this study, we assessed the impact of Arctium lappa L. polysaccharides (ALP) on the biological properties of nasal ectomesenchymal stem cells (EMSCs) and investigated the augmenting effect of ALP pretreatment on EMSCs (ALP-EMSCs) for the treatment of liver fibrosis. ALP treatment demonstrated multiple biological impacts on EMSC functions regarding liver fibrosis: firstly, it maintained the stemness of the cells while boosting the EMSCs' paracrine effects; secondly, it increased the expression of anti-inflammatory and antioxidant factors; thirdly, it inhibited the activation of hepatic stellate cells (HSCs) and liver collagen build-up by modulating the Wnt/ß-catenin signaling pathways. Collectively, these effects helped to halt the progression of liver fibrosis. Therefore, the use of ALP-EMSCs presents an innovative and promising approach for treating hepatic fibrosis in clinical scenarios.


Assuntos
Arctium , Células-Tronco Mesenquimais , Humanos , beta Catenina/metabolismo , Via de Sinalização Wnt , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo
4.
Nutrients ; 15(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38068804

RESUMO

The objective of this study was to investigate the preventive effects of polysaccharides extracted from the roots of Arctium lappa (ALP) against acute lung injury (ALI) models induced by lipopolysaccharide (LPS). The polysaccharides were extracted and characterized, and their anti-inflammatory and antioxidant capacities were assessed. The findings demonstrated that ALP could mitigate the infiltration of inflammatory cells and reduce alveolar collapse in LPS-induced ALI in mice. The expression levels of the pro-inflammatory factor TNF-α decreased, while the anti-inflammatory factor IL-10 increased. Furthermore, the administration of ALP improved the activities of lung antioxidant enzymes, including SOD, GSH, and CAT, and lowered MDA levels. These results suggest that ALP exhibits a preventive effect on ALI and has potential as an alternative treatment for lung injury.


Assuntos
Lesão Pulmonar Aguda , Arctium , Animais , Camundongos , Antioxidantes/metabolismo , Lipopolissacarídeos/farmacologia , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/prevenção & controle , Lesão Pulmonar Aguda/induzido quimicamente , Anti-Inflamatórios/uso terapêutico , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Polissacarídeos/metabolismo , Pulmão
5.
Nat Prod Res ; : 1-6, 2023 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-37867310

RESUMO

In this study, water-soluble polysaccharides purified from burdock root were used to intervene in carbon tetrachloride (CCl4)-induced acute liver injury (ALI) of BRL3A hepatocytes and rats. Our results indicated that CCl4 significantly inhibited hepatocyte viability and upregulated the expression of reactive oxygen species (ROS), malondialdehyde (MDA), pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6), and the pro-apoptotic protein Bax. However, Arctium lappa L. root polysaccharides (ALP) could effectively ameliorate liver function and histopathology, oxidative stress, and inflammatory markers. In addition, ALP reduced the expression of apoptotic markers and promoted the proliferation of damaged hepatocytes. In conclusion, ALP possesses a hepatoprotective effect mediated by attenuating oxidative damage, inflammation and apoptosis in ALI.

6.
Water Sci Technol ; 88(1): 1-10, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37452529

RESUMO

The heterogeneous Fenton process is a strategy for overcoming the greatest shortcomings of traditional homogeneous Fenton, i.e. the high generation of ferric hydroxide sludge and effectivity in a limited pH range. In this study, we constructed a heterogeneous Fenton system with natural iron-bearing clay mineral (nontronite) and dimethoxyhydroquinone (DMHQ) to degrade lincomycin (LCM) without the addition of H2O2. The degradation mechanism was derived from the hydroxyl radicals (•OH) produced from the oxygenation of Fe(II) in nontronites, which was reduced by DMHQ. Acidic conditions and low concentrations of LCM were favourable for LCM degradation. When the solution pH increased from 3 to 7, the final LCM removal ratio decreased from 95 to 46%. However, LCM can still be degraded by 46% under neutral conditions and 20% at the LCM concentration of 500 µmol/L. The nontronite has good reusability, and the LCM degradation efficiency in the fourth cycle still exceeded 90% of the original efficiency. The degradation sites of LCM mainly occurred in the methyl thioether moiety and the aliphatic amine group on the pyrrolidine ring, with the final product of CO2. This research presents a new eco-friendly and cost-effective method for the heterogenous Fenton process without external H2O2.


Assuntos
Radical Hidroxila , Ferro , Ferro/química , Radical Hidroxila/química , Argila , Peróxido de Hidrogênio/química , Minerais/química , Oxirredução
7.
Oncogene ; 42(22): 1843-1856, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37081042

RESUMO

Oncogenic stress induces DNA damage repair (DDR) that permits escape from mitotic catastrophe and allows early precursor lesions during the evolution of cancer. SAMHD1, a dNTPase protecting cells from viral infections, has been recently found to participate in DNA damage repair process. However, its role in tumorigenesis remains largely unknown. Here, we show that SAMHD1 is up-regulated in early-stage human carcinoma tissues and cell lines under oxidative stress or genotoxic insults. We further demonstrate that de-ubiquitinating enzyme USP7 interacts with SAMHD1 and de-ubiquitinates it at lysine 421, thus stabilizing SAMHD1 protein expression for further interaction with CtIP for DDR, which promotes tumor cell survival under genotoxic stress. Furthermore, SAMHD1 levels positively correlates with USP7 in various human carcinomas, and is associated with an unfavorable survival outcome in patients who underwent chemotherapy. Moreover, USP7 inhibitor sensitizes tumor cells to chemotherapeutic agents by decreasing SAMHD1 in vitro and in vivo. These findings suggest that de-ubiquitination of SAMHD1 by USP7 promotes DDR to overcome oncogenic stress and affect chemotherapy sensitivity.


Assuntos
Dano ao DNA , Reparo do DNA , Humanos , Peptidase 7 Específica de Ubiquitina/genética , Proteína 1 com Domínio SAM e Domínio HD/genética , Ubiquitinação
9.
J Cell Biol ; 222(5)2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36995368

RESUMO

Microvascular basement membrane (BM) plays a pivotal role in the interactions of astrocyte with endothelium to maintain the blood-brain barrier (BBB) homeostasis; however, the significance and precise regulation of the endothelial cell-derived BM component in the BBB remain incompletely understood. Here, we report that conditional knockout of Atg7 in endothelial cells (Atg7-ECKO) leads to astrocyte-microvascular disassociation in the brain. Our results reveal astrocytic endfeet detachment from microvessels and BBB leakage in Atg7-ECKO mice. Furthermore, we find that the absence of endothelial Atg7 downregulates the expression of fibronectin, a major BM component of the BBB, causing significantly reduced coverage of astrocytes along cerebral microvessels. We reveal Atg7 triggers the expression of endothelial fibronectin via regulating PKA activity to affect the phosphorylation of cAMP-responsive element-binding protein. These results suggest that Atg7-regulated endothelial fibronectin production is required for astrocytes adhesion to microvascular wall for maintaining the BBB homeostasis. Thus, endothelial Atg7 plays an essential role in astrocyte-endothelium interactions to maintain the BBB integrity.


Assuntos
Astrócitos , Proteína 7 Relacionada à Autofagia , Barreira Hematoencefálica , Animais , Camundongos , Astrócitos/metabolismo , Proteína 7 Relacionada à Autofagia/genética , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Endotélio/metabolismo , Fibronectinas/metabolismo , Membrana Basal/metabolismo , Adesão Celular
10.
Quant Imaging Med Surg ; 13(3): 1927-1936, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36915340

RESUMO

Background: Early identification of severe acute pancreatitis (SAP) is key to reducing mortality and improving prognosis. We aimed to establish a radiomics model and nomogram for early prediction of acute pancreatitis (AP) severity based on contrast-enhanced computed tomography (CT) images. Methods: We retrospectively analyzed 215 patients with first-episode AP, including 141 in the training cohort (87 men and 54 women, mean age 51.37±16.09 years) and 74 in the test cohort (40 men and 34 women, mean age 55.49±17.83 years). Radiomics features were extracted from portal venous phase images based on pancreatic and peripancreatic regions. The light gradient boosting machine (LightGBM) algorithm was used for feature selection, a logistic regression (LR) model was established and trained by 10-fold cross-validation, and a nomogram was established based on the best features. The model's predictive performance was evaluated according to the area under the curve (AUC) of the receiver operating characteristic (ROC) curve, sensitivity, specificity, and accuracy. Results: A total of 13 optimal radiomics features were selected by LightGBM for LR model building. The AUC of the radiomics (LR) model was 0.992 [95% confidence interval (CI): 0.963-0.996] in the training cohort, 0.965 (95% CI: 0.924-0.981) in the validation cohort, and 0.894 (95% CI: 0.789-0.966) in the test cohort. The sensitivity was 0.862 (95% CI: 0.674-0.954), the specificity was 0.800 (95% CI: 0.649-0.899), and the accuracy was 0.824 (95% CI: 0.720-0.919). The nomogram based on the 13 radiomics features showed that SAP would be predicted when the total score was greater than 124. Conclusions: The radiomics model based on enhanced-CT images of pancreatic and peripancreatic regions performed well in the early prediction of AP severity. The nomogram based on selected radiomics features could provide a reference for AP clinical assessment.

11.
Hepatology ; 78(5): 1433-1447, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36800849

RESUMO

BACKGROUND AND AIMS: Liver fibrosis is a leading indicator for increased mortality and long-term comorbidity in NASH. Activation of HSCs and excessive extracellular matrix production are the hallmarks of liver fibrogenesis. Tyrosine kinase receptor (TrkB) is a multifunctional receptor that participates in neurodegenerative disorders. However, paucity of literature is available about TrkB function in liver fibrosis. Herein, the regulatory network and therapeutic potential of TrkB were explored in the progression of hepatic fibrosis. METHODS AND RESULTS: The protein level of TrkB was decreased in mouse models of CDAHFD feeding or carbon tetrachloride-induced hepatic fibrosis. TrkB suppressed TGF-ß-stimulated proliferation and activation of HSCs in 3-dimensional liver spheroids and significantly repressed TGF-ß/SMAD signaling pathway either in HSCs or in hepatocytes. The cytokine, TGF-ß, boosted Nedd4 family interacting protein-1 (Ndfip1) expression, promoting the ubiquitination and degradation of TrkB through E3 ligase Nedd4-2. Moreover, carbon tetrachloride intoxication-induced hepatic fibrosis in mouse models was reduced by adeno-associated virus vector serotype 6 (AAV6)-mediated TrkB overexpression in HSCs. In addition, in murine models of CDAHFD feeding and Gubra-Amylin NASH (GAN), fibrogenesis was reduced by adeno-associated virus vector serotype 8 (AAV8)-mediated TrkB overexpression in hepatocytes. CONCLUSION: TGF-ß stimulated TrkB degradation through E3 ligase Nedd4-2 in HSCs. TrkB overexpression inhibited the activation of TGF-ß/SMAD signaling and alleviated the hepatic fibrosis both in vitro and in vivo . These findings demonstrate that TrkB could be a significant suppressor of hepatic fibrosis and confer a potential therapeutic target in hepatic fibrosis.


Assuntos
Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica , Fator de Crescimento Transformador beta , Animais , Camundongos , Tetracloreto de Carbono , Células Estreladas do Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Receptores Proteína Tirosina Quinases , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Smad/genética , Proteínas Smad/metabolismo
12.
Antiviral Res ; 210: 105513, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36592670

RESUMO

Antibody-based therapy is emerging as a critical therapeutic countermeasure to treat acute viral infections by offering rapid protection against clinical disease. The advancements in structural biology made it feasible to rationalize monoclonal antibodies (mAbs) by identifying key and, possibly, neutralizing epitopes of viral proteins for therapeutic purposes. A critical component in assessing mAbs during pandemics requires the development of rapid but detailed methods to detect and quantitate the neutralization activity. In this study, we developed and optimized two high-content image (HCI)-based assays: one to detect viral proteins by staining and the second to quantify cytopathic viral effects by a label-free phenotypic assay. These assays were employed to screen for therapeutic antibodies against the monkeypox virus (MPXV) using surrogate poxviruses such as vaccinia virus (VACV). Plaque-based neutralization results confirmed the HCI data. The phenotypic assay found pox virus-induced syncytia formation in various cells, and we were able to quantitate and use this phenotype to screen mAbs. The HCI identified several potent VACV-neutralizing antibodies that showed in vitro efficacy against both clades of MPXV. In addition, a combination study of ST-246/tecovirimat/TPOXX a single neutralizing antibody Ab-40, showed synergistic activity against VACV in an in-vitro neutralization assay. This rapid high-content method utilizing state-of-the-art technologies enabled the evaluation of hundreds of mAbs quickly to identify several potent anti-MPXV neutralizing mAbs for further development.


Assuntos
Anticorpos Antivirais , Vírus da Varíola dos Macacos , Anticorpos Neutralizantes , Vírus Vaccinia/genética , Proteínas Virais , Anticorpos Monoclonais/farmacologia , Testes de Neutralização
13.
J Nanobiotechnology ; 20(1): 519, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494806

RESUMO

BACKGROUND: Proliferative vitreoretinopathy (PVR) is a blind-causing disease initiated by the activation of retinal pigmented epithelium (RPE) primarily induced by TGF-ß families. Migrasome is a recently discovered type of extracellular vesicle related to cell migration. RESULTS: Here, we used ex vivo, in vitro, and in vivo models, to investigate the characteristics and functions of migrasomes in RPE activation and PVR development. Results indicated that the migrasome marker tetraspanin-4 (TSPAN4) was abundantly expressed in human PVR-associated clinical samples. The ex vivo model PVR microenvironment is simulated by incubating brown Norway rat RPE eyecups with TGF-ß1. Electron microscope images showed the formation of migrasome-like vesicles during the activation of RPE. Further studies indicated TGF-ß1 increased the expression of TSPAN4 which results in migrasome production. Migrasomes can be internalized by RPE and increase the migration and proliferation ability of RPE. Moreover, TSPAN4-inhibited RPE cells are with reduced ability of initiating experimental PVR. Mechanically, TSPAN4 expression and migrasome production are induced through TGF-ß1/Smad2/3 signaling pathway. CONCLUSION: In conclusion, migrasomes can be produced by RPE under PVR microenvironment. Migrasomes play a pivotal role in RPE activation and PVR progression. Thus, targeting TSPAN4 or blocking migrasome formation might be a new therapeutic method against PVR.


Assuntos
Fator de Crescimento Transformador beta1 , Vitreorretinopatia Proliferativa , Humanos , Fator de Crescimento Transformador beta1/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Vitreorretinopatia Proliferativa/tratamento farmacológico , Vitreorretinopatia Proliferativa/metabolismo , Epitélio Pigmentado da Retina , Movimento Celular , Epitélio , Células Cultivadas
14.
Cell Signal ; 100: 110466, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36100057

RESUMO

BACKGROUND AND AIM: Vascular endothelial cadherin (VE-cadherin) is an important element of adherens junctions (AJs) between endothelial cells. Its expression and proper distribution are critical for AJ formation and vascular integrity. Our previous studies have demonstrated that moesin phosphorylation mediated the hyper-permeability in endothelial monolayer and microvessels. However, the role of moesin and its phosphorylation in VE-cadherin expression and distribution is not clear. METHODS AND RESULTS: In vivo, expression of VE-cadherin was significantly reduced in retina and other various tissues in moesin knock out mice (Msn-/Y). In vitro, by regulating moesin expression with siRNA and adenovirus transfection, we verified that moesin has an effect on VE-cadherin expression in HUVECs, while transcription factor KLF4 may participate in this process. In addition, treatment of advanced glycation end products (AGEs) induced abnormal distribution of VE-cadherin in retinal microvessels from C57BL/6 wild type mice, and in vitro studies indicated that moesin Thr558 phosphorylation had a critical role in AGE-induced VE-cadherin internalization from cytomembrane to cytoplasm. Further investigation demonstrated that the inhibition of F-actin polymerization with cytochalasin D could abolish AGE- and Thr558 phosphor-moesin-mediated VE-cadherin internalization. CONCLUSION: This study suggests that moesin regulates VE-cadherin expression through KLF4 and the state of moesin phosphorylation at Thr558 affects the integrity of VE-cadherin-based AJs. Thr558 phosphor-moesin mediates AGE-induced VE-cadherin internalization through cytoskeleton reassembling.

15.
Macromol Rapid Commun ; 43(21): e2200419, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35748664

RESUMO

Hydrogels are promising material candidates in engineering soft robotics, mechanical sensors, biomimetic regenerative medicine, etc. However, developing multinetwork hydrogels with high mechanical properties and excellent printability are still challenging. Here, a bifunctional phenol-enabled sequential polymerization (BPSP) strategy is reported to fabricate high-performance multinetwork hydrogels under the orthogonal catalysis of efficient ruthenium photochemistry. Benefiting from this bifunctional design, phenols can sequentially polymerize with typical monomers and themselves to fabricate various phenol-containing polymers (Ph-Ps) and Ph-Ps-based multinetwork tough hydrogels, respectively. The as-prepared hydrogels have maximum stress of 0.75 MPa and toughness of 2.2 MJ m- 3 under the critical strain of 800%. These property parameters are a maximum of 16 times higher than those of the phenol-postmodified and phenol-free hydrogels. Moreover, the rapid coupling polymerization of phenols can shorten the gelation times of hydrogels to as low as ≈4 s, which enables its printable property for customizable applications. As a proof of concept, a 3D scaffold-like structure is optimized as highly sensitive mechanical sensors for detecting various human motions.


Assuntos
Hidrogéis , Fenol , Humanos , Hidrogéis/química , Polimerização , Polímeros/química
16.
Redox Biol ; 54: 102367, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35724543

RESUMO

Aberrant pro-inflammatory activation of Kupffer cells (KCs) is strongly involved in the pathogenesis of septic liver injury. Recent evidence indicates the crucial roles of excessive stimulator of interferon genes (STING) signaling activation during sepsis. However, the role of STING signaling in septic liver injury remains unclear. In this study, we demonstrated that STING signaling was markedly activated in KCs isolated from wild type mice after lipopolysaccharide (LPS) treatment. STING deficiency effectively protected liver function, attenuated systemic inflammatory response and decreased mortality in LPS-treated mice, which were aggravated by STING agonist (DMXAA). Importantly, STING signaling activation in KCs contributed to LPS-induced liver injury through promoting hepatocyte death. Mechanistically, STING signaling could be activated by release of mitochondrial DNA (mtDNA) through dynamin-related protein 1 (DRP1)-dependent mitochondrial fission in LPS-treated KCs. Additionally, LPS stimulation enhanced DRP1-dependent mitochondrial ROS production, which promoted the leak of mtDNA into the cytosol and subsequent STING signaling activation in KCs. The in vivo experiments showed that pharmacological inhibition of DRP1 with Mdivi-1 partially prevented the activation of STING signaling in KCs isolated from LPS-challenged mice, as well as alleviated liver injury and inhibited systemic inflammatory response. In summary, our study comprehensively confirmed that STING signaling senses the DRP1-dependent release of mtDNA in KCs and its activation might play a key role in LPS-induced liver injury, which offers new sights and therapeutic targets for management of septic liver injury.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Proteínas de Membrana , Sepse , Animais , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Dinaminas/genética , Dinaminas/metabolismo , Células de Kupffer/metabolismo , Lipopolissacarídeos/toxicidade , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Sepse/genética , Sepse/metabolismo
17.
Exp Eye Res ; 220: 109085, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35500674

RESUMO

A serious form of ocular fibrotic disease is proliferative vitreoretinopathy (PVR) that can ultimately lead to blindness. While the pathogenesis of PVR is known to be closely tied to retinal pigment epithelial (RPE) cell epithelial-mesenchymal transition (EMT) characterized by E-cadherin downregulation and N-cadherin upregulation. Herein, we developed a model of transforming growth factor-ß1 (TGF-ß1)-induced EMT using human RPE (hRPE) cells as a tool for exploring the mechanistic basis for E-cadherin to N-cadherin switching. This analysis revealed that the loss of E-cadherin led to the separation of ß-catenin from the catenin-cadherin complex whereupon it underwent nuclear entry to activate zinc finger E-box binding homeobox 1 (ZEB1), in turn promoting N-cadherin upregulation in this biological context. E-cadherin overexpression was sufficient to inhibit this EMT process and proliferation in RPE cells, further constraining their TGF-ß1-induced apoptosis.


Assuntos
Caderinas , Transição Epitelial-Mesenquimal , Fator de Crescimento Transformador beta1 , Vitreorretinopatia Proliferativa , Antígenos CD , Caderinas/metabolismo , Humanos , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Vitreorretinopatia Proliferativa/metabolismo
18.
Am J Transl Res ; 14(4): 2728-2738, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35559413

RESUMO

OBJECTIVE: This study aimed to investigate the changes in transepithelial electrical resistance (TEER) and ion concentrations, and their relationship in TGF-ß-induced epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells. METHODS: RPE cell line ARPE-19 was employed and treated with 10 ng/ml TGF-ß1 and TGF-ß2 to establish the EMT model in vitro. The EMT markers fibronectin, N-cadherin, occludin, zona occludens 1(ZO-1) and claudin-19 were investigated by western blot and immunofluorescence. CellZscope system was used to monitor the TEER values. Fluorescent probe, flow cytometry and automatic microplate reader were employed to detect the changes of Ca2+, Mg2+, Zn2+, Na+ and K+ in ARPE-19 cells. RESULTS: The TGF-ß1-induced EMT of ARPE-19 cells was marked by the disruption of the distribution of occludin, ZO-1, and claudin-19. The development of TEER was significantly disturbed in both TGF-ß1 and TGF-ß2 treatment groups. Also, the time course of the maximum slope indicated that the fastest decrease in TEER values occurred after 36 hours. The concentrations of Ca2+, Mg2+, Zn2+, and K+ increased in TGF-ß1- and TGF-ß2-treated ARPE-19 cells, while the concentration of Na+ decreased. Significant inverse correlations were detected between the concentrations of Ca2+, Mg2+, Zn2+, and K+ and TEER values in ARPE-19 cells treated with TGF-ß1. The Na+ concentration and TEER values showed a positive correlation. Similar results were observed in the TGF-ß2 treatment group. The time-effect analysis showed that the concentrations of Ca2+, Mg2+, Zn2+ and K+ increased and peaked after 72, 72, 48, and 72 h, respectively, with the extension of TGF-ß1 treatment time. In the TGF-ß2 treatment group, the Ca2+, Mg2+, Zn2+, and K+ concentrations were also upregulated and reached their highest after 72, 72, 72, and 36 h, respectively. In contrast, the concentration of Na+ decreased and reached the lowest after 48 h in the TGF-ß1 treatment group and after 72 h in the TGF-ß2 treatment group. CONCLUSION: TGF-ß1 and TGF-ß2 disrupted the ARPE-19 cell monolayer, disturbed TJs integrity, downregulated TEER values, and changed intracellular ion permeability. These findings might help further understand the EMT of RPE cells during PVR.

19.
Hum Vaccin Immunother ; 18(5): 2073757, 2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-35612817

RESUMO

In the context of the novel Coronavirus outbreak and China's official policy of free vaccination against COVID-19 for all, medical students' attitudes and knowledge toward vaccines can influence public acceptance to some extent, however, the large base of non-medical students cannot be ignored. We aimed to investigate the knowledge, attitude, and willingness toward the COVID-19 vaccine among medical and non-medical students. Online surveys were completed by 652 medical students and 590 non-medical students to compare differences in knowledge and attitude of COVID-19 vaccine and vaccination willingness from three universities in the Zhejiang Province. The awareness rate of the vaccine among medical students (65.3%) was higher than that of non-medical students (53.6%). The approval rate of medical students for the safety and efficacy of the COVID-19 vaccine was higher than that of non-medical students. 81.8% of university students were willing to be vaccinated against COVID-19; Multiple stepwise regression analyses showed that lower class grades, rural students' origin, COVID-19 vaccine attitude and higher cognition level of health self-management influenced the acceptance of COVID-19 vaccination among medical students. However, urban origin, COVID-19 vaccine attitude were the factors hindering non-medical students' vaccination against COVID-19. The knowledge, attitude and willingness toward the COVID-19 vaccine on medical and non-medical students had different characteristics. Moreover, health self-management was associated with COVID-19 vaccination willingness. Staff involved in the university should pay more attention to the self-managementability of students, send out accurate and transparent information to enhance their cognitive level, further improving the students' willingness to receive the COVID-19 vaccine.


Assuntos
COVID-19 , Estudantes de Medicina , COVID-19/prevenção & controle , Vacinas contra COVID-19 , China , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Vacinação
20.
Cell Rep ; 39(2): 110656, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35417709

RESUMO

Tight junctions (TJs) of brain microvascular endothelial cells (BMECs) play a pivotal role in maintaining the blood-brain barrier (BBB) integrity; however, precise regulation of TJs stability in response to physiological and pathological stimuli remains elusive. Here, using RNA immunoprecipitation with next-generation sequencing (RIP-seq) and functional characterization, we identify SNHG12, a long non-coding RNA (lncRNA), as being critical for maintaining the BBB integrity by directly interacting with TJ protein occludin. The interaction between SNHG12 and occludin is oxygen adaptive and could block Itch (an E3 ubiquitin ligase)-mediated ubiquitination and degradation of occludin in human BMECs. Genetic ablation of endothelial Snhg12 in mice results in occludin reduction and BBB leakage and significantly aggravates hypoxia-induced BBB disruption. The detrimental effects of hypoxia on BBB could be alleviated by exogenous SNHG12 overexpression in brain endothelium. Together, we identify a direct TJ modulator lncRNA SNHG12 that is critical for the BBB integrity maintenance and oxygen adaption.


Assuntos
Barreira Hematoencefálica , RNA Longo não Codificante , Animais , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Hipóxia/metabolismo , Camundongos , Ocludina/metabolismo , Ocludina/farmacologia , Oxigênio/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
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