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1.
Anal Chem ; 94(38): 12948-12953, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36102588

RESUMO

The precise manipulation of single cells plays a fundamental role for single cell measurement, which is crucial for understanding the diverse cellular mechanisms. Unusual single cell behavior could thus be identified by integrating with advanced analytical methods such as single cell omics, unraveling the intrinsic cellular heterogeneity hidden in ensemble measurements. Herein, this technical note reports a nanopipet-based versatile method for manipulation of an ultrasmall volume of liquid, which further enables the precise manipulation of single cells. Femtoliter volumes of cytoplasm were extracted from single living cells and analyzed by time-of-flight secondary ion mass spectrometry. Moreover, several kinds of exogenous components were injected simultaneously into a cell, offering a delicate tool for multi-imaging in single living cells.


Assuntos
Análise de Célula Única , Espectrometria de Massa de Íon Secundário , Análise de Célula Única/instrumentação
2.
Sleep Breath ; 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35943692

RESUMO

PURPOSE: Patients with obstructive sleep apnoea (OSA) have a high incidence of vascular endothelial injury. The most important pathophysiological feature of OSA is chronic intermittent hypoxia (CIH). This study aimed to investigate the mechanisms of CIH-related vascular endothelial injury. METHODS: IH exposure was applied to human umbilical vein endothelial cells (HUVECs). After modeling, cell viability, the expression levels of peroxisome proliferator activated receptor γ (PPARγ), apoptosis-associated proteins and mitochondrial division fusion proteins, and the levels of reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were assessed via Cell Counting Kit-8 (CCK-8), western blotting, fluorescent microscope, and flow cytometry, respectively. Rosiglitazone (PPARγ agonist), tempo (the mitochondrial-specific antioxidant), and tempo combined with PPARγ interfering RNA were used to treat HUVECs, respectively. RESULTS: After IH exposure, cell viability and levels of MMP decreased, cell apoptosis and ROS levels increased, and the expression levels of PPARγ decreased. Both tempo and rosiglitazone pretreatment ameliorated cell apoptosis and improved cell viability. In addition, mitochondrial function became better after tempo pretreatment. PPARγ interference reversed the protective effects of tempo on IH-related mitochondrial function injury and cell injury. CONCLUSIONS: PPARγ regulated the apoptosis and cell viability of IH-treated HUVECs by altering mitochondrial function. This finding clarifies the mechanism of CIH-related vascular endothelial injury.

3.
Oxid Med Cell Longev ; 2022: 5981353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35757504

RESUMO

Silibinin is a flavonoid extracted from the medicinal plant Silybum marianum (milk thistle), traditionally used to treat liver disease. Recent studies have shown that the antioxidative stress and anti-inflammatory effects of milk thistle are used in the treatment of neurological diseases. Silibinin has antioxidative stress and antiapoptotic effects and reduces cognitive impairment in models of Alzheimer's disease (AD). However, the underlying mechanism of silibinin related to improvement of cognition remains poorly understood. In this study, we used the model of lateral ventricle injection of formaldehyde to examine the related mechanism of silibinin in improving cognitive impairment disorders. Oral administration of silibinin for three weeks significantly attenuated the cognitive deficits of formaldehyde-induced mice in a Y-maze test and Morris water maze test. Y-maze results show that silibinin increases the rate of spontaneous response alternation in FA-induced mice. Silibinin increases the target quadrant spending time and decreases escape latency in the Morris water maze test. We examined the effect of silibinin on the NRF2 signaling pathway, and silibinin promoted the nuclear transfer of NRF2 and increased the expression of HO-1 but did not significantly increase the protein expression of NRF2 in the hippocampus. Well, silibinin reduces the content of DHE and decreases the levels of apoptosis of mature neuron cells. We investigated the effect of silibinin on the content of formaldehyde degrading enzymes; biochemical analyses revealed that silibinin increased GSH and ALDH2 in formaldehyde-induced mice. In addition, as one of the pathological changes of AD, TAU protein is also hyperphosphorylated in FA model mice. Silibinin inhibits the expression of GSK-3ß in model mice, thereby reducing the phosphorylation of TAU proteins ser396 and ser404 mediated by GSK3ß. Based on our findings, we verified that the mechanism of silibinin improving cognitive impairment may be antioxidative stress, and silibinin is one of the potentially promising drugs to prevent formaldehyde-induced cognitive impairment.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Silimarina , Doença de Alzheimer/metabolismo , Animais , Antioxidantes/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/metabolismo , Formaldeído/toxicidade , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/metabolismo , Transtornos da Memória/tratamento farmacológico , Camundongos , Cardo-Mariano , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Silibina/farmacologia , Silimarina/farmacologia
4.
Phytopathology ; : PHYTO04220120R, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-35731021

RESUMO

Previous studies in Botrytis cinerea showed that resistance to methyl benzimidazole carbamates (MBCs) was mainly related to E198A/V/K and F200Y mutations of the ß-tubulin gene, and E198V was the dominant mutation in the resistant subpopulation in Hubei Province of China, indicating that resistant mutations might influence fitness. However, little is known about the effect of each E198A/V/K mutation on fitness. In this study, the fitness and competitive ability of isolates with E198A/V/K mutations were investigated. Results showed that E198A/V/K isolates and wild-type isolates shared similar fitness components in terms of virulence, sporulation, conidial germination, oxidative sensitivity, and sclerotial production and viability. However, slower mycelial growth at 4°C, higher sensitivity to 4% NaCl, and increased sclerotial production percentage at 4°C were observed in the isolates with E198V, E198K, and E198A mutations, respectively. Competitive analysis showed that the wild-type subpopulation became dominant after three disease cycles in the absence of fungicide selection pressure, whereas the resistant subpopulation seized the space of the sensitive subpopulation upon MBC application. Unexpectedly, the frequency of E198V isolates decreased dramatically after the first disease cycle with or without fungicide selection pressure. These results suggest that MBC-resistant isolates suffer little fitness penalty but possess competitive disadvantages in the absence of fungicide selection pressure. Under fungicide selection pressure, E198V isolates could not compete with E198A/K isolates. According to the current results, there is a great possibility that the E198V mutation will lose dominance in the future in China.

5.
Gastroenterol Res Pract ; 2022: 5142473, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35419053

RESUMO

Background: It is critical to accurately identify patients with severe acute pancreatitis (SAP) and moderately SAP (MSAP) in a timely manner. The study was done to establish two early multi-indicator prediction models of MSAP and SAP. Methods: Clinical data of 469 patients with acute pancreatitis (AP) between 2015 and 2020, at the First Affiliated Hospital of Fujian Medical University, and between 2012 and 2020, at the Affiliated Union Hospital of Fujian Medical University, were retrospectively analyzed. The unweighted predictive score (unwScore) and weighted predictive score (wScore) for MSAP and SAP were derived using logistic regression analysis and were compared with four existing systems using receiver operating characteristic curves. Results: Seven prognostic indicators were selected for incorporation into models, including white blood cell count, lactate dehydrogenase, C-reactive protein, triglyceride, D-dimer, serum potassium, and serum calcium. The cut-offs of the unwScore and wScore for predicting severity were set as 3 points and 0.513 points, respectively. The unwScore (AUC = 0.854) and wScore (AUC = 0.837) were superior to the acute physiology and chronic health evaluation II score (AUC = 0.526), the bedside index for severity in AP score (AUC = 0.766), and the Ranson score (AUC = 0.693) in predicting MSAP and SAP, which were equivalent to the modified computed tomography severity index score (AUC = 0.823). Conclusions: The unwScore and wScore have good predictive value for MSAP and SAP, which could provide a valuable clinical reference for management and treatment.

6.
Front Bioeng Biotechnol ; 10: 806177, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35284405

RESUMO

This paper proposes a hybrid swarming algorithm based on Ant Colony Optimization and Physarum Polycephalum Algorithm. And the Van Der Waals force is first applied to the pheromone update mechanism of the hybrid algorithm. The improved method can prevent premature convergence into the local optimal solution. Simulation results show the proposed approach has excellent in solving accuracy and convergence time. We also compare the improved algorithm with other advanced algorithms and the results show that our algorithm is more accurate than the literature algorithms. In addition, we use the capitals of 35 Asian countries as an example to verify the robustness and versatility of the hybrid algorithm.

7.
Adv Sci (Weinh) ; 9(2): e2102949, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34747141

RESUMO

Adipose thermogenesis plays a pivotal role in whole-body metabolic homeostasis. Although transcriptional mechanisms that promote thermogenesis are extensively studied, the negative regulatory network is still poorly understood. Here, a Krüppel-associated box (KRAB) domain-containing zinc finger protein, ZFP961, as a potent repressor of the thermogenic program is identified. ZFP961 expression is induced by cold and ß3-adrenergic agonist in adipose tissue. ZFP961 represses brown fat-selective gene expression and mitochondrial respiration without any effect on general adipogenesis in cultured adipocytes. Adipose-specific knockdown and overexpression of ZFP961 produce remarkable and opposite phenotypes of white fat remodeling. ZFP961 knockout mice display robust inguinal white adipose tissue browning, which is abolished by reexpression of full-length ZFP961, but not by KRAB domain-deleted ZFP961 mutant. ZFP961-deficient mice are cold tolerant and resistant to high-fat diet-induced obesity, hyperglycemia, and hepatic steatosis. ZFP961 suppresses thermogenic gene expression by directly interacting with PPARα and blocking its transcriptional activity, which can be completely negated by the PPARα agonist. The findings uncover ZFP961 as a critical physiological brake that limits adipose thermogenesis and provides insights into the regulatory mechanisms that maintain energy balance and tissue homeostasis.


Assuntos
Tecido Adiposo/metabolismo , Metabolismo Energético/genética , PPAR alfa/genética , PPAR alfa/metabolismo , Termogênese/genética , Dedos de Zinco/genética , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
8.
Dis Markers ; 2021: 5759927, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34853622

RESUMO

The clinical TNM staging system is currently used to evaluate the prognosis of head and neck squamous cell carcinoma (HNSCC). The 5-year survival rate for patients with HNSCC is less than 50%, which is attributed to the lack of reliable prognostic biomarkers. Ferroptosis-related genes (FRGs) regulate cancer initiation and progression. Therefore, we analyzed the correlation between FRGs and the clinical outcomes of patients with HNSCC. A typical prognostic model of FRGs for HNSCC was constructed using bioinformatics tools and data from public databases, including The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and GeneCards. The model was generated based on the following six FRGs: ATG5, PRDX6, OTUB1, FTH1, SOCS1, and MAP3K5. The accuracy of model prediction was analyzed systematically. The overall survival (OS) of the high-risk group was significantly lower than that of the low-risk group. The AUC for 1-year, 3-year, and 5-year survival were 0.645, 0.721, and 0.737, respectively, in the training set (TCGA cohort) and 0.726, 0.620, and 0.584, respectively, in the validation set (GSE65858). The multivariate Cox regression analysis revealed that the risk score was an independent prognostic factor for HNSCC. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses revealed that six FRGs were enriched in the ferroptosis pathway. A novel FRG prognostic signature model was established for HNSCC. The findings of this study reveal that FRGs are potential biomarkers for HNSCC.


Assuntos
Biomarcadores Tumorais/metabolismo , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/patologia , Nomogramas , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Idoso , Biomarcadores Tumorais/genética , Biologia Computacional , Feminino , Seguimentos , Perfilação da Expressão Gênica , Ontologia Genética , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Taxa de Sobrevida
10.
Ecotoxicol Environ Saf ; 227: 112911, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34673411

RESUMO

Chromium (Cr) as a chromate anion has a strong redox capacity that seriously threatens the ecological environment and human health. Cr can contaminate water and impart toxicity to aquatic species. Procambarus clarkii is an important food source that once represented a large proportion of the aquaculture industry due to its rapid reproduction and high economic value. However, there have been reports on the death of P. clarkii due to heavy metal pollution. The underlying mechanism regarding heavy metal toxicity was studied in this paper. The transcriptome data of hemocytes extracted from P. clarkii injected with Cr were analyzed by high-throughput sequencing and compared to the control group. In total, 48,128,748 clean reads were obtained in the treatment group and 56,480,556 clean reads were obtained in the control group. The reads were assembled using Trinity and the identified unigenes were then annotated. Then, 421 differentially-expressed genes (DEGs) were found, 170 of which were upregulated and 251 downregulated. Many of these genes were found to be related to glutathione metabolism and transportation. The glutathione metabolic pathway of P. clarkii was thus activated by Cr exposure to detoxify and maintain body function. Validation of DEGs with quantitative real-time PCR confirms the changes in gene expression. Thus, this study provides data supporting a glutathione-focused response of P. clarkii to exposure to heavy metals.


Assuntos
Astacoidea , Clarkia , Animais , Antioxidantes , Astacoidea/genética , Cromo/toxicidade , Mecanismos de Defesa , Perfilação da Expressão Gênica , Humanos , Transcriptoma
11.
Artigo em Inglês | MEDLINE | ID: mdl-34333232

RESUMO

Ovarian development is a complex physiological process for crustacean reproduction that is divided into the oogonium proliferation stage, endogenous vitellogenic stage, exogenous vitellogenic stage, and oocyte maturation stage. Proteomics analysis offers a feasible approach to reveal the proteins involved in the complex physiological processes of any organism. Therefore, this study performed a comparative proteomics analysis of the ovary and hepatopancreas at three key ovarian stages, including stages I (oogonium proliferation), II (endogenous vitellogenesis) and IV (exogenous vitellogenesis), of the Chinese mitten crab Eriocheir sinensis using a label-free quantitative approach. The results showed that a total of 2,224 proteins were identified, and some key proteins related to ovarian development and nutrition metabolism were differentially expressed. The 26 key proteins were mainly involved in the ubiquitin/proteasome pathway (UPP), cyclic AMP-protein kinase A (cAMP-PKA) signaling pathway, and mitogen-activated protein kinase (MAPK) signaling pathway during oogenesis. Fifteen differentially abundant proteins (DAPs) were found to participate in vitellogenesis and oocyte development, such as vitelline membrane outer layer protein 1 homolog, vitellogenin, vitellogenin receptor, heat shock 70 kDa protein cognate 3 and farnesyl pyrophosphate synthase. Forty-seven DAPs related to nutrition metabolism were identified, including the protein digestion, fatty acid metabolism, prostaglandin metabolism, lipid digestion and transportation, i.e. short-chain specific acyl-CoA dehydrogenase, acyl-CoA desaturase, fatty acid-binding protein, long-chain fatty acid CoA ligase 4, and hematopoietic prostaglandin D synthase. These results not only indicate proteins involved in ovarian development and nutrient deposition but also enhance the understanding of the regulatory pathways and physiological processes of crustacean ovarian development.


Assuntos
Braquiúros , Proteômica , Animais , China , Feminino , Hepatopâncreas , Ovário , Vitelogênese
12.
Front Pharmacol ; 12: 627875, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34054517

RESUMO

We have shown that cholesterol regulates the activity of ion channels in mouse cortical collecting duct (CCD) mpkCCDc14 cells and that the transient receptor potential melastatin 4 (TRPM4) channel is expressed in these cells. However, whether TRPM4 channel is regulated by cholesterol remains unclear. Here, we performed inside-out patch-clamp experiments and found that inhibition of cholesterol biosynthesis by lovastatin significantly decreased, whereas enrichment of cholesterol with exogenous cholesterol significantly increased, TRPM4 channel open probability (Po) by regulating its sensitivity to Ca2+ in mpkCCDc14 cells. In addition, inside-out patch-clamp data show that acute depletion of cholesterol in the membrane inner leaflet by methyl-ß-cyclodextrin (MßCD) significantly reduced TRPM4 Po, which was reversed by exogenous cholesterol. Moreover, immunofluorescence microscopy, Western blot, cell-surface biotinylation, and patch clamp analysis show that neither inhibition of intracellular cholesterol biosynthesis with lovastatin nor application of exogenous cholesterol had effect on TRPM4 channel protein abundance in the plasma membrane of mpkCCDc14 cells. Sucrose density gradient centrifugation studies demonstrate that TRPM4 was mainly located in cholesterol-rich lipid rafts. Lipid-protein overlay experiments show that TRPM4 directly interacted with several anionic phospholipids, including PI(4,5)P2. Depletion of PI(4,5)P2 with either wortmannin or PGE2 abrogated the stimulatory effects of exogenous cholesterol on TRPM4 activity, whereas exogenous PI(4,5)P2 (diC8-PI(4,5)P2, a water-soluble analog) increased the effects. These results suggest that cholesterol stimulates TRPM4 via a PI(4,5)P2-dependent mechanism.

13.
Sci Rep ; 11(1): 4492, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627750

RESUMO

Chinese mitten crab (Eriocheir sinensis) as a commercially important species is widely cultured in China. However, E. sinensis is prone to agonistic behavior, which causes physical damage and wastes energy resources, negatively impacting their growth and survival. Therefore, understanding the regulatory mechanisms that underlie the switching of such behavior is essential for ensuring the efficient and cost-effective aquaculture of E. sinensis. The 5-HT2B receptor is a key downstream target of serotonin (5-HT), which is involved in regulating animal behavior. In this study, the full-length sequence of 5-HT2B gene was cloned. The total length of the 5-HT2B gene was found to be 3127 bp with a 236 bp 5'-UTR (untranslated region), a 779 bp 3'-UTR, and a 2112 bp open reading frame encoding 703 amino acids. Phylogenetic tree analysis revealed that the 5-HT2B amino acid sequence of E. sinensis is highly conserved with that of Cancer borealis. Using in vitro co-culture and luciferase assays, the miR-143 targets the 5-HT2B 3'-UTR and inhibits 5-HT2B expression was confirmed. Furthermore, RT-qPCR and Western blotting analyses revealed that the miR-143 mimic significantly inhibits 5-HT2B mRNA and protein expression. However, injection of miR-143 did not decrease agonistic behavior, indicating that 5-HT2B is not involved in the regulation of such behavior in E. sinensis.


Assuntos
Comportamento Agonístico/fisiologia , Braquiúros/genética , MicroRNAs/genética , Serotonina/genética , Regiões 3' não Traduzidas/genética , Regiões 5' não Traduzidas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , China , Clonagem Molecular , DNA Complementar/genética , Perfilação da Expressão Gênica/métodos , Fases de Leitura Aberta/genética , Filogenia , RNA Mensageiro/genética , Alinhamento de Sequência
14.
Sci Adv ; 7(6)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33536206

RESUMO

PD-1/PD-L1 blockade therapies provide notable clinical benefits for patients with advanced cancers, but the factors influencing the effectiveness of the treatment remain incompletely cataloged. Here, the up-regulation of laminin γ2 (Ln-γ2) predicted the attenuated efficacy of anti-PD-1 drugs and was associated with unfavorable outcomes in patients with lung cancer or esophageal cancer. Furthermore, Ln-γ2 was transcriptionally activated by transforming growth factor-ß1 (TGF-ß1) secreted from cancer-associated fibroblasts via JNK/AP1 signaling, which blocked T cell infiltration into the tumor nests by altering the expression of T cell receptors. Coadministration of the TGF-ß receptor inhibitor galunisertib and chemotherapy drugs provoked vigorous antitumor activity of anti-PD-1 therapy in mouse tumor models. Therefore, Ln-γ2 may represent a useful biomarker to optimize clinical decisions and predict the response of cancer patients to treatment with anti-PD-1 drugs.

15.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-429007

RESUMO

The SARS-CoV-2 viral genome contains a positive-strand single-stranded RNA of ~30 kb. Human ACE2 protein is the receptor for SARS-CoV-2 virus attachment and initiation of infection. We propose to use ribonucleases (RNases) as antiviral agents to destroy the viral genome in vitro. In the virions the RNA is protected by viral capsid proteins, membrane proteins and nucleocapsid proteins. To overcome this protection we set out to construct RNase fusion with human ACE2 receptor N-terminal domain (ACE2NTD). We constructed six proteins expressed in E. coli cells: 1) MBP-ACE2NTD, 2) ACE2NTD-GFP, 3) RNase I (6xHis), 4) RNase III (6xHis), 5) RNase I-ACE2NTD (6xHis), and 6) human RNase A-ACE2NTD150 (6xHis). We evaluated fusion expression in different E. coli strains, partially purified MBP-ACE2NTD protein from the soluble fraction of bacterial cell lysate, and refolded MBP-ACE2NTD protein from inclusion body. The engineered RNase I-ACE2NTD (6xHis) and hRNase A-ACE2NTD (6xHis) fusions are active in cleaving COVID-19 RNA in vitro. The recombinant RNase I (6xHis) and RNase III (6xHis) are active in cleaving RNA and dsRNA in test tube. This study provides a proof-of-concept for construction of fusion protein between human cell receptor and nuclease that may be used to degrade viral nucleic acids in our environment. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=132 SRC="FIGDIR/small/429007v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@1b966e0org.highwire.dtl.DTLVardef@1111393org.highwire.dtl.DTLVardef@1c4cc2org.highwire.dtl.DTLVardef@1f35dd7_HPS_FORMAT_FIGEXP M_FIG Cartoon illustration part of this work (Human ACE2 N-terminal domain tethered to RNase A and RNA degradation by the fusion enzyme). C_FIG

16.
Inorg Chem ; 60(4): 2756-2763, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33480675

RESUMO

A series of cationic cyclometalated iridium(III) complexes with o-carborane cage on the main ligand of 2-phenylbenzothiazole were synthesized. The prepared iridium complexes (C1-C6) were fully characterized by UV-vis, NMR, and FT-IR spectra. The exact molecular structure of complex C1 was further studied by single crystal X-ray diffraction analysis. The different substitution position of o-carborane on the 2-phenylbenzothiazole ring lead to obvious differences in the emission properties of the synthesized complexes. The o-carboranyl unit results in a bathochromic shift of 10 nm in the fluorescence emission spectrum of C2. In addition, the presence of an o-carborane fragment promoted the strong fluorescence intensity of C1 and C4, which can be used as a tool to effectively boost the intensity of fluorescence properties. The emission fluorescent behavior of iridium(III) complexes can be facilely tuned by structural variations in the main ligands of these materials.

17.
Biochim Biophys Acta Mol Basis Dis ; 1867(1): 165989, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33065235

RESUMO

We previously showed that increased epithelial sodium channel (ENaC) activity in endothelial cells induced by oxidized low-density lipoprotein (ox-LDL) contributes to vasculature dysfunction. Here, we investigated whether ENaC participates in the pathological process of atherosclerosis using LDL receptor-deficient (LDLr-/-) mice. Male C57BL/6 and LDLr-/- mice were fed a normal diet (ND) or high fat diet (HFD) for 10 weeks. Our data show that treatment of LDLr-/- mice with a specific ENaC blocker, benzamil, significantly decreased atherosclerotic lesion formation and expression of matrix metalloproteinase 2 (MMP2) and metalloproteinase 9 (MMP9) in aortic arteries. Furthermore, benzamil ameliorated HFD-induced impairment of aortic endothelium-dependent dilation by reducing expression of proinflammatory cytokines, including TNF-α, IL-1ß, and IL-6 and production of adhesion molecules including VCAM-1 and ICAM-1 in both C57BL/6 and LDLr-/- mice fed with HFD. In addition, HFD significantly increased ENaC activity and the levels of serum lipids, including ox-LDL. Our in vitro data further demonstrated that exogenous ox-LDL significantly increased the production of TNF-α, IL-1ß, IL-6, VCAM-1 and ICAM-1. This ox-LDL-induced increase in inflammatory cytokines and adhesion molecules was reversed by γ-ENaC silencing or by treatment with the cyclooxygenase-2 (COX-2) antagonist celecoxib. Benzamil inhibited HFD-induced increase in COX-2 expression in aortic tissue in both C57BL/6 and LDLr-/- mice, and γ-ENaC gene silencing attenuated ox-LDL-induced COX-2 expression in HUVECs. These data together suggest that HFD-induced activation of ENaC stimulates inflammatory signaling, thereby contributes to HFD-induced endothelial dysfunction and atherosclerotic lesion formation. Thus, targeting endothelial ENaC may be a promising strategy to halt atherogenesis.


Assuntos
Aterosclerose , Dieta Hiperlipídica/efeitos adversos , Canais Epiteliais de Sódio/metabolismo , Receptores de LDL/deficiência , Animais , Aterosclerose/induzido quimicamente , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Citocinas/genética , Citocinas/metabolismo , Canais Epiteliais de Sódio/genética , Células Endoteliais da Veia Umbilical Humana , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Lipoproteínas LDL/genética , Lipoproteínas LDL/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Receptores de LDL/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
18.
Cell Death Differ ; 28(3): 952-967, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33037394

RESUMO

Dysregulation of the balance between cell proliferation and cell death is a central feature of malignances. Death-associated protein kinase 3 (DAPK3) regulates programmed cell death including apoptosis and autophagy. Our previous study showed that DAPK3 downregulation was detected in more than half of gastric cancers (GCs), which was related to tumor invasion, metastasis, and poor prognosis. However, the precise molecular mechanism underlying DAPK3-mediated tumor suppression remains unclear. Here, we showed that the tumor suppressive function of DAPK3 was dependent on autophagy process. Mass spectrometry, in vitro kinase assay, and immunoprecipitation revealed that DAPK3 increased ULK1 activity by direct ULK1 phosphorylation at Ser556. ULK1 phosphorylation by DAPK3 facilitates the ULK1 complex formation, the VPS34 complex activation, and autophagy induction upon starvation. The kinase activity of DAPK3 and ULK1 Ser556 phosphorylation were required for DAPK3-modulated tumor suppression. The coordinate expression of DAPK3 with ULK1 Ser556 phosphorylation was confirmed in clinical GC samples, and this co-expression was correlated with favorable survival outcomes in patients. Collectively, these findings indicate that the tumor-suppressor roles of DAPK3 in GC are associated with autophagy and that DAPK3 is a novel autophagy regulator, which can directly phosphorylate ULK1 and activate ULK1. Thus, DAPK3 might be a promising prognostic autophagy-associated marker.


Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Autofagia/fisiologia , Proteínas Quinases Associadas com Morte Celular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Gástricas/genética , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Quinases Associadas com Morte Celular/metabolismo , Feminino , Genes Supressores de Tumor , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Fosforilação , Ensaios Antitumorais Modelo de Xenoenxerto
19.
World J Clin Cases ; 8(22): 5535-5546, 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33344544

RESUMO

BACKGROUND: Coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in China, constitutes a Public Health Emergency of International Concern. It is well known that COVID-19 patients may have increased serum lactate dehydrogenase (LDH) levels in the early stage. The clinical changes in LDH may have predictive value in disease evolution and prognosis in critically ill COVID-19 patients. AIM: To examine serum LDH and clinical characteristics in patients with COVID-19 and their predictive value for prognosis. METHODS: This retrospective study analyzed the clinical data of forty-seven critical COVID-19 patients in the intensive care unit of the Third People's Hospital of Yichang City from January 27 to March 25, 2020 and divided them into survivors and non-survivors. The patients were diagnosed according to the World Health Organization interim guidance and critical cases met any one of the following criteria: Respiratory failure and required mechanical ventilation, the occurrence of shock, and the combined failure of other organs that required intensive care unit monitoring and treatments, according to the diagnostic criteria of critical COVID-19. Clinical data including symptoms, detection of SARS-CoV-2, chest computed tomography (CT) images, changes in serum LDH in different clinical phases, and prognosis were collected. Statistical analysis of the data was performed. Continuous variables were expressed as median (interquartile range) and compared with the Mann-Whitney U test. Categorical variables were compared with the Chi-square test. Survival data were analyzed using Kaplan-Meier survival curves and log-rank tests. RESULTS: According to chest CT images, we observed the alveolitis and fibrosis stages in all critical patients in this study. Most non-survivors died in the fibrosis stage. Non-survivors had fewer days of hospitalization, shorter disease duration, shorter duration of alveolitis and fibrosis, and had dyspnea symptoms at disease onset (P = 0.05). Both first and lowest LDH values in the alveolitis stage were more pronounced in non-survivors than in survivors (449.0 U/L vs 288.0 U/L, P = 0.0243; 445.0 U/L vs 288.0 U/L, P = 0.0199, respectively), while the first, lowest and highest values of serum LDH in non-survivors were all significantly increased compared to survivors in the fibrosis phase (449.0 U/L vs 225.5 U/L, P = 0.0028; 432.0 U/L vs 191.0 U/L, P = 0.0007; 1303.0 U/L vs 263.5 U/L, P = 0.0001, respectively). The cut-off points of first LDH values in the alveolitis and fibrosis phase for distinction of non-survivors from survivors were 397.0 U/L and 263.0 U/L, respectively. In the fibrosis stage, non-survivors had more days with high LDH than survivors (7.0 d vs 0.0 d, P = 0.0002). Importantly, patients with high LDH had a significantly shorter median survival time than patients with low LDH in the alveolitis phase (22.0 d vs 36.5 d, P = 0.0002), while patients with high LDH also had a significantly shorter median survival time than patients with low LDH in the fibrosis phase (27.5 d vs 40.0 d, P = 0.0008). The proportion of non-survivors with detectable SARS-CoV-2 until death in the alveolitis stage was significantly increased compared with that in the fibrosis stage (100% vs 35.7%, P = 0.0220). CONCLUSION: High LDH and dyspnea symptoms were positive predictors of an adverse outcome in critical COVID-19. The rapid progressive fibrosis stage was more perilous than the alveolitis stage, even if SARS-CoV-2 is undetectable.

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