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1.
Small ; 20(24): e2309937, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38178644

RESUMO

High entropy materials offer almost unlimited catalytic possibilities due to their variable composition, unique structure, and excellent electrocatalytic performance. However, due to the strong tendency of nanoparticles to coarsen and agglomerate, it is still a challenge to synthesize nanoparticles using simple methods to precisely control the morphology and size of the nanoparticles in large quantities, and their large-scale application is limited by high costs and low yields. Herein, a series of high-entropy oxides (HEOs) nanoparticles with high-density and ultrasmall size (<5 nm) loaded on carbon nanosheets with large quantities are prepared by Joule-heating treatment of gel precursors in a short period of time (≈60 s). Among them, the prepared (FeCoNiRuMn)3O4-x catalyst shows the best electrocatalytic activity for oxygen evolution reaction, with low overpotentials (230 mV @10 mA cm-2, 270 mV @100 mA cm-2), small Tafel slope (39.4 mV dec-1), and excellent stability without significant decay at 100 mA cm-2 after 100 h. The excellent performance of (FeCoNiRuMn)3O4-x can be attributed to the synergistic effect of multiple elements and the inherent structural stability of high entropy systems. This study provides a more comprehensive design idea for the preparation of efficient and stable high entropy catalysts.

2.
Phys Chem Chem Phys ; 26(12): 9617-9627, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38466129

RESUMO

Theoretical calculations are performed to elucidate the adsorption behaviors and poisoning effects of CO gas on the ZrCo surface, which drastically limits its application in hydrogen isotopic storage. Specifically, the ionic Zr-Co bond on the surface leads to unique CO adsorption structures on different sites. The CO molecule tends to prefer a tilted adsorption configuration on the Co-Co bridge site. The electronic structures, charge distributions, and bonding characteristics are further explored to study the CO adsorption properties, which obey the electron density donation and back-donation mechanism. For different CO coverages, the stepwise adsorption energies of CO increase with the increasing of coverage, reaching the saturated coverage at nCO = 11. Then, the effects of temperature and partial pressure on CO coverage are evaluated using atomic thermodynamics. The computed phase diagram shows that the ZrCo(110) surface has a stable coverage of nCO = 6 at ambient temperature under ultrahigh vacuum conditions. The pre-adsorbed CO molecules lead to the charge redistribution and the d-band center downshift on the surface, which significantly affect hydrogen adsorption and dissociation. Our results provide insights into the poisoning mechanisms of the impurity gas on ZrCo alloys, which can be beneficial for designing high-performance ZrCo-based alloys with improved poisoning tolerance.

3.
Postgrad Med J ; 100(1180): 84-90, 2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-37857513

RESUMO

BACKGROUND: It has been reported that patients with cholelithiasis may have changes in levels of cytokines and growth factors, while their causal relationships were still unclear. METHODS: This study was a bidirectional Mendelian randomization (MR) study. Datasets of 41 circulation cytokines and growth factors and the data on cholelithiasis were obtained. Six steps of strict instrumental variable filtration were set, and inverse-variance weighted analysis, MR-Egger regression, and weighted median test were used to identify the causal relationships. Benjamini-Hochberg method was used to adjust the P-values. RESULTS: After adjustments of P-values, four cytokines and growth factors were still causally associated with cholelithiasis significantly: interleukin 2 receptor alpha (adjusted P: 4.59E-02), interleukin 8 (adjusted P: 1.09E-02), monocyte-specific chemokine 3 (adjusted P: 2.73E-04), and stem cell factor (adjusted P: 2.73E-04). In the reverse MR analysis, no significant causal relationship was detected after adjustment. CONCLUSIONS: Four cytokines and growth factors, including interleukin 2 receptor alpha, interleukin 8, monocyte-specific chemokine 3, and stem cell factor, were proven to relate to cholelithiasis causally and unidirectionally.


Assuntos
Citocinas , Interleucina-8 , Humanos , Fator de Células-Tronco , Subunidade alfa de Receptor de Interleucina-2 , Análise da Randomização Mendeliana , Peptídeos e Proteínas de Sinalização Intercelular/genética , Estudo de Associação Genômica Ampla
4.
BMC Ophthalmol ; 23(1): 141, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37020269

RESUMO

BACKGROUND: To evaluate the aqueous humor (AH) levels of cytokines in primary open-angle glaucoma (POAG) patients and cataract patients. METHODS: Thirty-eight POAG patients and 26 cataract patients were recruited. Peripheral blood (PB) was collected from each subject. The POAG group was divided into 2 subgroups according to the severity of visual field defects. The cutoff point of the mean deviation (MD) of the visual field was -12 dB. AH was obtained at the time of anterior chamber puncture during cataract or glaucoma surgery by using a 27-gauge needle attached to a microsyringe. AH and PB levels of interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-α), transforming growth factor-beta2 (TGF-ß2) and IL-4 were assayed by enzyme-linked immunosorbent assay. Postoperative intraocular pressures (IOPs) of POAG patients were recorded during the follow-up period. RESULTS: TNF-α and TGF-ß2 showed significantly higher AH levels in the POAG group than in the cataract group (P < 0.001 and P = 0.001, respectively). For the POAG group, preoperative IOPs were significantly positively correlated with AH levels of TNF-α (r2 = 0.129, P = 0.027) and TGF-ß2 (r2 = 0.273, P = 0.001). AH levels of TGF-ß2 were significantly different among cataract patients, POAG patients with MD> -12 dB and POAG patients with MD≤ -12 dB (P = 0.001). AH levels of TNF-α were significantly positively associated with IOP reduction after trabeculectomy (P = 0.025). AH and PB levels of cytokines were not related to the long-term success of trabeculectomy. CONCLUSION: The levels of TNF-α and TGF-ß2 showed different profiles in POAG patients and cataract patients. AH levels of TGF-ß2 were correlated with the severity of glaucomatous neuropathy in POAG patients. The findings suggest possible roles for cytokines in the pathogenesis and development of POAG.


Assuntos
Humor Aquoso , Catarata , Citocinas , Glaucoma de Ângulo Aberto , Humanos , Glaucoma de Ângulo Aberto/cirurgia , Campos Visuais , Humor Aquoso/metabolismo , Citocinas/sangue , Pressão Intraocular , Interleucina-2/sangue , Interleucina-4/sangue , Fator de Crescimento Transformador beta2/sangue , Fator de Necrose Tumoral alfa/sangue , Masculino , Feminino , Pessoa de Meia-Idade
5.
Toxicol Appl Pharmacol ; 432: 115758, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34678374

RESUMO

Mitochondrial dysfunction is a major factor in nonalcoholic fatty liver disease (NAFLD), preceding insulin resistance and hepatic steatosis. Carnosol (CAR) is a kind of diterpenoid with antioxidant, anti-inflammatory and antitumor activities. Peroxiredoxin 3 (PRDX3), a mitochondrial H2O2-eliminating enzyme, undergoes overoxidation and subsequent inactivation under oxidative stress. The purpose of this study was to investigate the protective effect of the natural phenolic compound CAR on NAFLD via PRDX3. Mice fed a high-fat diet (HFD) and AML-12 cells treated with palmitic acid (PA) were used to detect the molecular mechanism of CAR in NAFLD. We found that pharmacological treatment with CAR notably moderated HFD- and PA- induced steatosis and liver injury, as shown by biochemical assays, Oil Red O and Nile Red staining. Further mechanistic investigations revealed that CAR exerted anti-NAFLD effects by inhibiting mitochondrial oxidative stress, perturbation of mitochondrial dynamics, and apoptosis in vivo and in vitro. The decreased protein and mRNA levels of PRDX3 were accompanied by intense oxidative stress after PA intervention. Interestingly, CAR specifically bound PRDX3, as shown by molecular docking assays, and increased the expression of PRDX3. However, the hepatoprotection of CAR in NAFLD was largely abolished by specific PRDX3 siRNA, which increased mitochondrial dysfunction and exacerbated apoptosis in vitro. In conclusion, CAR suppressed lipid accumulation, mitochondrial dysfunction and hepatocyte apoptosis by activating PRDX3, mitigating the progression of NAFLD, and thus, CAR may represent a promising candidate for clinical treatment of steatosis.


Assuntos
Abietanos/farmacologia , Apoptose/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Peroxirredoxina III/metabolismo , Animais , Antioxidantes/farmacologia , Linhagem Celular , Dieta Hiperlipídica , Modelos Animais de Doenças , Ativação Enzimática , Hepatócitos/enzimologia , Hepatócitos/patologia , Fígado/enzimologia , Fígado/patologia , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Hepáticas/patologia , Dinâmica Mitocondrial/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/efeitos dos fármacos , Ácido Palmítico/toxicidade , Peroxirredoxina III/genética
6.
Toxicol Appl Pharmacol ; 403: 115125, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32659284

RESUMO

Epithelial-mesenchymal transition (EMT) is regulated by reactive oxygen species (ROS) in liver fibrosis. p66Shc is a redox enzyme, but its role of EMT is unclear in liver fibrosis. Long noncoding RNAs (lncRNAs) have been implicated as important regulators in numerous physiological and pathological processes and generally acting as a microRNA (miRNA) sponge to regulate gene expression. The aim of the current study was to evaluate the contribution of p66Shc to EMT in liver fibrosis and the regulation of p66Shc by lncRNA sponge. In vivo, p66Shc silencing prevented carbon tetrachloride (CCl4)-induced EMT as evidenced by the upregulation of E-cadherin, downregulation of Vimentin and N-cadherin, and inhibition of oxidative stress and extracellular matrix (ECM) components. Moreover, in vitro, TGF-ß1 significantly enhanced ECM components, as well as the development of the EMT phenotype. These effects were abrogated by p66Shc downregulation and aggravated by p66Shc overexpression. Mechanistically, p66Shc contributed to EMT via mediating ROS, as evidenced by p66Shc downregulation inhibiting EMT under exogenous hydrogen peroxide (H2O2) stimulation. Furthermore, we found that molecule interacting with CasL2 (Mical2) lncRNA functioned as an endogenous miR-203a-3p sponge to regulate p66Shc expression. Both Mical2 silencing and miR-203a-3p agomiR treatment downregulated p66Shc expression, thus suppressing EMT in vivo and in vitro. Notably, the increased p66Shc and Mical2 levels and decreased miR-203a-3p levels in murine fibrosis were consistent with those in patients with liver fibrosis. In sum, our study reveals that p66Shc is critical for liver fibrosis and that Mical2, miR-203a-3p and p66Shc compose a novel regulatory pathway in liver fibrosis.


Assuntos
Transição Epitelial-Mesenquimal/fisiologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Animais , Intoxicação por Tetracloreto de Carbono , Linhagem Celular , Regulação para Baixo , Regulação da Expressão Gênica , Inativação Gênica , Hepatócitos , Humanos , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Masculino , Camundongos , MicroRNAs/genética , RNA Longo não Codificante/genética , Distribuição Aleatória , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética
7.
J Cell Biochem ; 120(9): 15963-15970, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31081222

RESUMO

BACKGROUND: Gastric cancer (GC) is the fifth most common cancer type worldwide. The aim of this study was to identify gastric-related therapeutic indicators on the basis of the ego network analysis. MATERIAL AND METHODS: The microarray data related to GC was downloaded from ArrayExpress database. All human protein-protein interaction (PPI) networks were downloaded from the STRING database. Ego genes were identified on the basis of PPI networks and the gene expression in GC, and then co-expression networks (ego networks) were constructed using these ego genes. On the basis of ego networks, the optimal GO terms and genes were predicted by affinity predictions and cold read predictions. Finally, the predicted genes as effective biomarkers for GC were verified by the bioinformatics analysis. RESULTS: The differential expression networks were conducted and comprised of 365 edges and 232 nodes, which resulted in 218 ego genes. Although there was no significant difference in the expression of top ten ego genes among different groups of GC samples, it was eventually confirmed that top three optimal GO terms with highest cool read values were translational termination (cool read value = 0.987), translational elongation (cool read value = 0.986), and macromolecular complex disassembly (cool read value = 0.985) and top five optimal genes were UBA52, RPS27A, MAPK1, UBC, and UBB. UBA52, RPS27A, and MAPK1 were verified by the bioinformatics analysis to be related to the progression and metastasis of GC. CONCLUSIONS: An ego network analysis approach is a very effective method for screening GC and the screened genes might be biomarkers for GC diagnosis and treatment.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Redes Reguladoras de Genes , Neoplasias Gástricas/genética , Bases de Dados Genéticas , Progressão da Doença , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Neoplásica , Mapas de Interação de Proteínas , Neoplasias Gástricas/metabolismo
8.
J Cell Biochem ; 120(5): 7998-8007, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30548656

RESUMO

Long noncoding RNA (lncRNA) may regulate the process of tumor formation. Although lncRNA CCAT2 has been identified as a key point in many diseases, its pathophysiological mechanism in lung adenocarcinoma remains unknown. We measured the expression level of CCAT2 in lung adenocarcinoma cells and normal lung epithelial cell line BEAS-2B by quantitative real-time polymerase chain reaction (qRT-PCR). As well, cell migration and proliferation were detected by transwell detection and CCK8 assay. At the same time, the new target point of CCAT2 was confirmed with bioinformatics analysis and dual-luciferase reporter assay. In addition, potential mechanisms were studied by Western blot analysis and RNA immunoprecipitation (RIP) analysis. The expression of CCAT2 was upregulated obviously in lung adenocarcinoma cells. Cell function analysis showed that upregulation of CCAT2 significantly promoted cell proliferation and migration, and reduction of CCAT2 inhibited cell migration and proliferation. In addition, CCAT2 positively regulated the expression of FOXC1 by competitive binding with miR-23b-5p. These findings indicated that CCAT2 may act as a competitive endogenous RNA (ceRNA) to regulate FOXC1 expression by competitively binding miR-23b-5p in lung adenocarcinoma.

9.
Cell Mol Biol (Noisy-le-grand) ; 65(6): 44-51, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31472046

RESUMO

This study was carried out to investigate cell-free DNA (cfDNA) as a potential biomarker for colorectal cancer diagnosis.Patients with colorectal cancer (n = 25) who had not undergone surgery, and 35 patients with postoperative colorectal cancer were enrolled. Peripheral blood samples were collected from the colorectal cancer subjects (experimental group), and also from 30 healthy volunteers (control group). Quantitative PCR (qPCR) was used to determine cfDNA concentration and integrity in each group. The cfDNA levels of the two groups were analyzed to determine the relationship between the cfDNA and the clinical features of colorectal cancer patients. The receiver operator curve (ROC) was used to analyze sensitivity and specificity of cfDNA, carcinoembryonic antigen (CEA), cancer antigen 199 (CA199) and cancer antigen 125 (CA125). cfDNA concentration and cfDNA integrity in patients with colorectal cancer before surgery were significantly higher than those in patients with colorectal cancer after surgery, and cfDNA concentration of colorectal cancer patients after surgery was also significantly higher than that of the healthy control group, but the integrity was not significantly different from the control group. There was no significant correlation between cfDNA concentration/integrity and gender, age, disease stage, tumor location, tumor differentiation, and expressions of cancer antigen 153 (CA153), neuron specific enolase (NSE) and alpha fetoprotein (AFP) in colorectal cancer patients before or after surgery. However, there was a significant correlation between the expression levels of CEA/CA125 and concentration of cfDNA. The CA199 expression level was significantly correlated with cfDNA integrity. The sensitivity and specificity of cfDNA and integrity were higher than those used for traditional tumor biomarker detection. cfDNA concentration is significantly increased in serum of colorectal cancer patients. Thus, it may serve as a potential indicator of colorectal cancer.


Assuntos
Ácidos Nucleicos Livres/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/cirurgia , Adulto , Idoso , Cirurgia Colorretal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
10.
Exp Cell Res ; 371(1): 250-254, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30118695

RESUMO

Ninety percent of all cancer related deaths happen due to metastatic progression. One important protein facilitating metastatic progression in hepatocellular carcinoma (HCC) is the metastasis associated 1 protein (MTA-1). We have earlier shown that in the context of HCC and normal liver cell lines, HuH6 and THLE-2, respectively. MTA-1 protein is actively stabilized in HCC cell lines and actively degraded in normal liver cells. We had also shown that TRIM25 is the E3 ligase that interacts with and degrades MTA-1 protein in normal liver cells. However, the exact mechanism by which TRIM25 degrades MTA-1 protein has still not been elucidated. In the study, we used both in situ prediction algorithms and mass spectrometry based post-translational modification analysis to map the lysine residues in MTA-1 that are polyubiquitinated. Whereas UbPred algorithm revealed a combination of medium and low confidence sites, it revealed only one high confidence lysine (K98) residue. The hCKSAAP_UbSite algorithm also predicted K98 site. Mass spectrometry analysis also showed that K98 has ubiquitin modification. Immunofluorescence analysis showed that in normal liver cell line, THLE-2, which has high expression of TRIM25, ectopically expressed FLAG-tagged wild-type MTA-1 was actively degraded, but the K98R mutant MTA-1 was not. In vitro ubiquitination assay using recombinant wild-type and K98R mutant MTA-1 confirmed that MTA-1 is poly-ubiquitinated at K98 residue by TRIM25. The K98R mutant had a longer half-life than wild-type MTA-1 protein in an in vitro protein stability assay. We establish that TRIM25 ubiquitinates MTA-1 at lysine 98 and degrades it normal liver cells.


Assuntos
Histona Desacetilases/metabolismo , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Regiões 3' não Traduzidas , Sequência de Aminoácidos , Linhagem Celular , Hepatócitos , Histona Desacetilases/genética , Humanos , Espectrometria de Massas , Engenharia de Proteínas/métodos , Estabilidade Proteica , Proteólise , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/genética , Máquina de Vetores de Suporte , Transativadores , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Proteínas com Motivo Tripartido/antagonistas & inibidores , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
11.
Exp Cell Res ; 368(1): 37-41, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29654742

RESUMO

Tumor metastasis accounts for 90% of all cancer-related deaths. Epithelial to mesenchymal transition (EMT) considered to be centrally important in acquired resistance to chemotherapy and in progression of tumors to secondary organs. One of the important mediators of metastatic progression in hepatocellular carcinoma (HCC) is the metastasis associated protein 1 (MTA-1). We have earlier shown that in the context of HCC and normal liver cell lines, MTA-1 protein is actively stabilized in HCC cell lines and actively degraded in normal liver cells. We have also shown that TRIM25 is the E3 ligase that interacts with and degrades MTA-1 protein. The identity of the factor regulating expression of TRIM25 in normal liver cells and HCC is unknown. In the current work we elucidate that microRNA (miR)- 873 targets TRIM25 in HCC cells. Both metagenomic analysis and quantification of miR-873 and TRIM25 in 25 HCC patients revealed an inverse correlation between the two in HCC patients with high miR-873 and low TRIM25 expression, respectively. The expression pattern was mimicked in the normal liver cells THLE-2 and the HCC cell line, HuH6. In vitro luciferase reporter assays confirmed TRIM25 as the target of miR-873. Transient transfection of HuH6 cells with an anti-miR-873 antagomir significantly decreased both transwell motility in these cells. Furthermore, in in vivo xenograft assays treatment with anti-miR-873 antagomir significantly decreased hepatic nodules formation. Cumulatively, our data indicate that suppression of TRIM25 expression by high levels of miR-873 dictates MTA1 protein upregulation in HCC.


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Histona Desacetilases/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Humanos , Transativadores
12.
Apoptosis ; 23(11-12): 667-678, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30284149

RESUMO

Epithelial apoptosis is an important factor in intestinal ischemia-reperfusion (I/R) injury. Heat shock factor 1 (HSF1) is a classical stress response factor that directly regulates the transcription of heat shock proteins (HSPs) under stress conditions. Although HSPs are involved in protecting the intestine against I/R, the mechanism whereby HSF1 is regulated in I/R is poorly understood. Here, we show that the ubiquitin ligase FBXW7 targets HSF1 for ubiquitination and degradation in intestinal I/R. In this study, we found that FBXW7 expression was upregulated at the transcriptional level in intestinal mucosae subjected to I/R. In Caco-2 and IEC-6 cells subjected to hypoxia/reoxygenation (H/R), a high FBXW7 level led to excessive HSF1 ubiquitination and degradation. FBXW7 knockdown attenuated HSF1 ubiquitination and downregulation and accelerated HSPB1 and HSP70 expression. In addition, FBXW7 deletion alleviated the apoptosis of intestinal epithelial cells, as evidenced by decreased activation of caspase-3 and caspase-9. The results suggest that FBXW7 suppression protects against intestinal I/R, at least partly through the HSF1/HSP pathway. These findings indicate that FBXW7 may be a potential therapeutic target for inhibiting intestinal mucosa apoptosis during intestinal I/R.


Assuntos
Proteína 7 com Repetições F-Box-WD/metabolismo , Fatores de Transcrição de Choque Térmico/metabolismo , Intestinos/patologia , Traumatismo por Reperfusão/prevenção & controle , Ubiquitinação , Animais , Apoptose , Células CACO-2 , Linhagem Celular , Núcleo Celular/metabolismo , Modelos Animais de Doenças , Proteína 7 com Repetições F-Box-WD/genética , Deleção de Genes , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Camundongos Endogâmicos C57BL , Fosforilação , Ratos , Traumatismo por Reperfusão/genética , Transdução de Sinais , Ativação Transcricional
13.
Cell Physiol Biochem ; 48(4): 1579-1594, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30071511

RESUMO

BACKGROUND/AIMS: Ischemic postconditioning (iPoC) represents a promising strategy to mitigate ischemia/reperfusion (I/R) injury of the intestine, yet the mechanisms of this treatment remain to be elucidated. Circular RNAs (circRNAs), a novel class of endogenous non-coding RNAs, have recently been recognized as important regulators of gene expression and pathological processes. Here, we aimed to investigate the expression patterns of circRNAs after intestinal I/R with and without iPoC and, furthermore, to explore the potential mechanisms of iPoC in relation to the differentially expressed circRNAs. METHODS: The global circRNA and mRNA expression profiles in mouse intestinal mucosa were initially screened by microarray (n = 3 per group) and quantitative real-time PCR was used to validate the expression pattern of circRNAs and mRNAs. Bioinformatics analysis including Gene ontology, KEGG pathway analysis, microRNA binding sites identification and circRNA-miRNA-mRNA network construction were utilized for in-depth mechanism exploration. RESULTS: There were 4 up- and 58 downregulated circRNAs as well as 322 up- and 199 downregulated mRNAs in the intestinal I/R group compared with the sham group, whereas compared with I/R, iPoC treatment significantly upregulated 12 circRNAs and 129 mRNAs and downregulated 21 circRNAs and 174 mRNAs. The expression levels of a randomly selected set of 6 circRNAs and 5 mRNAs were successfully validated by qRT-PCR. Through a systematic comparison of the direction of circRNA expression changes in all groups, we identified two circRNAs, circRNA_012412 and circRNA_016863, that may be closely associated with the protective mechanisms of iPoC. Finally, four possible circRNA_012412/circRNA_016863-miRNA-mRNA pathways were predicted, which may play important roles in endogenous protective signaling in iPoC. CONCLUSIONS: This study was the first to comprehensively delineate the expression profiles of circRNAs in a mouse model of intestinal I/R and iPoC and provides novel clues for understanding the mechanisms of iPoC against intestinal I/R injury.


Assuntos
Intestinos/patologia , RNA/metabolismo , Traumatismo por Reperfusão/patologia , Animais , Biologia Computacional , Modelos Animais de Doenças , Regulação para Baixo , Pós-Condicionamento Isquêmico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Circular , RNA Mensageiro/metabolismo , Traumatismo por Reperfusão/genética , Fator de Necrose Tumoral alfa/sangue , Regulação para Cima
14.
Toxicol Appl Pharmacol ; 339: 172-180, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29253500

RESUMO

Carnosic acid (CA), a major bioactive component in rosemary extract, has many biological and pharmaceutical activities. Smad3 acetylation can regulate the transcription of type I α2 collagen (COL1A2), which is the major component of the extracellular matrix (ECM). The aim of the current study was to evaluate whether CA inhibits COL1A2 transcription via the reduction of Smad3 acetylation against liver fibrosis. The results showed that CA treatment significantly suppressed COL1A2 transcription and markedly decreased the deposition of ECM induced by dimethylamine (DMN) in rats. Importantly, the suppression of COL1A2 transcription following CA treatment depended on the reduction of Smad3 acetylation via the activation of Sirtuin 1 (SIRT1), a nicotinamide adenine dinucleotide+ (NAD+)-dependent deacetylase. SIRT1 siRNA increased the acetylation of Smad3 and blocked CA-down-regulated Smad3 deacetylation. Notably, CA-mediated AMP-activated protein kinase-α1 (AMPKα1) activation not only increased AMPKα1 phosphorylation but also increased SIRT1 expression, thus leading to a significant reduction in Smad3 acetylation. Furthermore, CA-mediated SIRT1 activation was inhibited by AMPKα1 siRNA. Collectively, CA can inhibit the transcription of COL1A2 through SIRT1-mediated Smad3 deacetylation, and the activation of SIRT1 by CA involves the AMPKα1/SIRT1 pathway in liver fibrosis.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Abietanos/farmacologia , Colágeno Tipo I/metabolismo , Sirtuína 1/metabolismo , Proteína Smad3/metabolismo , Transcrição Gênica/fisiologia , Acetilação/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Colágeno Tipo I/antagonistas & inibidores , Colágeno Tipo I/genética , Cirrose Hepática/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transcrição Gênica/efeitos dos fármacos
15.
Toxicol Appl Pharmacol ; 350: 21-31, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29729281

RESUMO

In recent years, alcoholic liver disease (ALD) has emerged as a growing public health problem worldwide. ß-catenin plays an important role in the growth, development, regeneration and metabolic activity of the liver. Salvianolic acid A (SalA) is a water-soluble component from the root extract of Salvia miltiorrhiza Bunge, and its effect on ALD has not yet been investigated. This study aimed to investigate the effect of SalA on chronic alcohol-induced liver injury and to explore the role of SIRT1-mediated ß-catenin deacetylation in such an effect. In this study, SalA treatment significantly alleviated the accumulation of lipid droplets and reduced the plasma alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), alcohol and ammonia levels in rats. SalA enhanced ethanol and ammonia metabolism and maintained mitochondrial homeostasis. Moreover, SalA restored the activity of the major ethanol-metabolizing enzymes and oxidative stress functions in the liver. Importantly, we found that SalA treatment effectively inhibited the ethanol-mediated decrease in nuclear ß-catenin by upregulating SIRT1 in the liver. SIRT1 then deacetylated ß-catenin to promote its accumulation in the nucleus, thereby preventing alcohol-induced liver injury. The results demonstrate that the SIRT1/ß-catenin pathway is a key therapeutic target in liver injury caused by chronic alcohol exposure and that SalA protects against alcohol-induced liver injury via the SIRT1-mediated deacetylation of ß-catenin.


Assuntos
Ácidos Cafeicos/uso terapêutico , Nucléolo Celular/metabolismo , Lactatos/uso terapêutico , Hepatopatias Alcoólicas/tratamento farmacológico , Hepatopatias Alcoólicas/metabolismo , Sirtuína 1/metabolismo , beta Catenina/metabolismo , Animais , Ácidos Cafeicos/farmacologia , Nucléolo Celular/efeitos dos fármacos , Doença Crônica , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Lactatos/farmacologia , Hepatopatias Alcoólicas/patologia , Masculino , Camundongos , Inibidores da Bomba de Prótons/farmacologia , Inibidores da Bomba de Prótons/uso terapêutico , Ratos , Ratos Sprague-Dawley
16.
Pharmacol Res ; 128: 327-337, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29106960

RESUMO

Quiescent hepatic stellate cell (HSC) activation and subsequent conversion into myofibroblasts is the central event in hepatic fibrosis pathogenesis. Epithelial-mesenchymal transition (EMT), another vital participant in liver fibrosis, has the potential to initiate HSC activation, which promotes abundant myofibroblast production. Previous studies suggest that Enhancer of Zeste Homolog 2 (EZH2) plays a significant role in myofibroblast transdifferentiation; however, the underlying mechanisms remain largely unaddressed. Carnosol (CS), a compound extracted from rosemary, displays multiple pharmacological activities. This study aimed to investigate the signaling mechanisms underlying EZH2 inhibition and the anti-fibrotic effect of CS in liver fibrosis. We found that CS significantly inhibited CCl4- and TGFß1-induced liver fibrosis and reduced both HSC activation and EMT. EZH2 knockdown also prevented these processes induced by TGFß1 in HSCs and AML-12 cells. Interestingly, the protective effect of CS was positively associated with Sirtuin 1 (SIRT1) activation and accompanied by EZH2 inhibition. SIRT1 knockdown attenuated the EZH2 inhibition induced by CS and increased EZH2 acetylation, which enhanced its stability. Conversely, upon TGFß1 exposure, SIRT1 activation significantly reduced the level of EZH2 acetylation; however, EZH2 overexpression prevented the SIRT1 activation that primed myofibroblast inhibition, indicating that EZH2 is a target of SIRT1. Thus, SIRT1/EZH2 regulation could be used as a new therapeutic strategy for fibrogenesis. Together, this study provides evidence of activation of the SIRT1/EZH2 pathway by CS that inhibits myofibroblast generation, and thus, CS may represent an attractive candidate for anti-fibrotic clinical therapy.


Assuntos
Abietanos/farmacologia , Abietanos/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Cirrose Hepática/tratamento farmacológico , Sirtuína 1/metabolismo , Animais , Tetracloreto de Carbono , Linhagem Celular , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Camundongos , Ratos Sprague-Dawley , Sirtuína 1/genética , Fator de Crescimento Transformador beta1
17.
IUBMB Life ; 69(10): 795-801, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28861931

RESUMO

Metastasis associated 1 protein (MTA1) is one of the prime facilitators of metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the underlying regulatory mechanism of MTA1 expression in HCC is not clear. In this study, we evaluated MTA1 transcript and protein expression in HCC and normal hepatic cell lines. The results revealed that MTA1 protein expression had a significantly increase in HCC cell line, HuH6, compared with that in normal hepatic cell line, THLE-2. Determination of protein half-life using cycloheximide (CHX) treatment did not reveal any statistically significant difference in protein turn-over rates between THLE-2 (3.3 ± 0.25 h) and HuH6 (3.6 ± 0.15 h) cell lines. MTA1 protein level was stabilized in THLE-2 cells after treatment with MG-132 to levels similar to those observed in HuH6 cells. Mass spectrometric analysis of FLAG immunoprecipitates of FLAG-MTA1 transfected THLE-2 cells after MG-132 treated revealed candidate ubiquitin ligases that were interacting with MTA1. RNAi-mediated silencing of each prospective ubiquitin ligase in THLE-2 cells indicated that knockdown of TRIM25 resulted in stabilization of MTA1 protein, indicating TRIM25 as a putative E3 ligase for MTA1. Coimmunoprecipitation of FLAG-tagged MTA1, but not IgG, in MG-132 treated and untreated THLE-2 cells cotransfected with either FLAG-MTA1 or Myc-TRIM25 revealed robust polyubiquitinated MTA1, confirming that the TRIM25 is the ubiquitin ligase for MTA1 degradation. Overexpression of TRIM25 in HuH6 and RNAi mediated silencing of TRIM25 in THLE-2 cells inhibited and increased the cell migration and invasion, respectively. Analysis of The Cancer Genome Atlas data for assessment of TRIM25 transcript level and MTA1 protein expression in 25 HCC patients confirmed an inverse correlation between the expression of TRIM25 and MTA1. Cumulatively, our data reveal a novel mechanism of post-translational to regulate MTA1 expression in normal hepatic cells, which is repressed in HCC. © 2017 IUBMB Life, 69(10):795-801, 2017.


Assuntos
Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Hepatócitos/metabolismo , Histona Desacetilases/genética , Neoplasias Hepáticas/genética , Proteínas Repressoras/genética , Fatores de Transcrição/genética , Proteínas com Motivo Tripartido/genética , Ubiquitina-Proteína Ligases/genética , Atlas como Assunto , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular , Cicloeximida/farmacologia , Progressão da Doença , Meia-Vida , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Histona Desacetilases/metabolismo , Humanos , Leupeptinas/farmacologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Ligação Proteica , Estabilidade Proteica/efeitos dos fármacos , Proteólise/efeitos dos fármacos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Transativadores , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Proteínas com Motivo Tripartido/antagonistas & inibidores , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/efeitos dos fármacos
18.
Clin Sci (Lond) ; 131(8): 759-773, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28232511

RESUMO

Intestinal epithelial oxidative stress and apoptosis constitute key pathogenic mechanisms underlying intestinal ischemia/reperfusion (I/R) injury. We previously reported that the adaptor 66 kDa isoform of the adaptor molecule ShcA (p66Shc)-mediated pro-apoptotic pathway was activated after intestinal I/R. However, the upstream regulators of the p66Shc pathway involved in intestinal I/R remain to be fully identified. Here, we focused on the role of a prolyl-isomerase, peptidyl-prolyl cis-trans isomerase (Pin1), in the regulation of p66Shc activity during intestinal I/R. Intestinal I/R was induced in rats by superior mesenteric artery (SMA) occlusion. Juglone (Pin1 inhibitor) or vehicle was injected intraperitoneally before I/R challenge. Caco-2 cells were exposed to hypoxia/reoxygenation (H/R) in vitro to simulate an in vivo I/R model. We found that p66Shc was significantly up-regulated in the I/R intestine and that this up-regulation resulted in the accumulation of intestinal mitochondrial reactive oxygen species (ROS) and massive epithelial apoptosis. Moreover, intestinal I/R resulted in elevated protein expression and enzyme activity of Pin1 as well as increased interaction between Pin1 and p66Shc. This Pin1 activation was responsible for the translocation of p66Shc to the mitochondria during intestinal I/R, as Pin1 suppression by juglone or siRNA markedly blunted p66Shc mitochondrial translocation and the subsequent ROS generation and cellular apoptosis. Additionally, Pin1 inhibition alleviated gut damage and secondary lung injury, leading to improvement of survival after I/R. Collectively, our findings demonstrate for the first time that Pin1 inhibition protects against intestinal I/R injury, which could be partially attributed to the p66Shc-mediated mitochondrial apoptosis pathway. This may represent a novel prophylactic target for intestinal I/R injury.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Intestinos/irrigação sanguínea , Naftoquinonas/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/antagonistas & inibidores , Lesão Pulmonar Aguda/patologia , Lesão Pulmonar Aguda/prevenção & controle , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Mucosa Intestinal/metabolismo , Intestinos/patologia , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Terapia de Alvo Molecular/métodos , Naftoquinonas/farmacologia , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/fisiologia , Translocação Genética
19.
IUBMB Life ; 68(5): 394-402, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27079864

RESUMO

MicroRNA-409-3p (miR-409-3p) is an miRNA expressed by embryonic stem cells, and our previous study demonstrated depressed miR-409-3p expression in human breast cancer (BC) cell lines; however, its role and function in BC metastasis are still unknown. The purpose of this study was to examine the expression levels of miR-409-3p in human BC and its role in the metastasis of BC. We analyzed the status of miR-409-3p expression in BC tissues by quantitative real-time polymerase chain reaction (PCR) and its relationship to the clinicopathologic features of patients with BC. To study the role of miR-409-3p in BC metastasis, the invasion ability of BC cells was detected by transwell invasion assays and wound healing assays. WST-1 assays and colony formation assays were used to investigate cell proliferation. Luciferase reporter assays were used to verify that miR-409-3p targeted zinc-finger E-box-binding homeobox 1 (ZEB1). Western blot analyses and transwell assays were carried out to assess ZEB1 expression and its role in BC cell metastasis. The expression of miR-409-3p was lower in tumor tissues than in noncancerous breast tissues. We verified that miR-409-3p levels were downregulated and significantly correlated with poor outcomes in patients with BC. Overexpression of miR-409-3p inhibited cellular proliferation and suppressed cellular migration and invasion in vitro and in vivo. Dual-luciferase reporter assays showed that miR-409-3p binds the 3'-untranslated region (3'-UTR) of ZEB1, suggesting that ZEB1 is a direct target of miR-409-3p. Western blot analysis confirmed that overexpression of miR-409-3p reduced ZEB1 protein levels. These data demonstrate that miR-409-3p plays an important role in regulating the metastasis of BC, which is involved in the post-transcriptional repression of ZEB1. Our results indicate that miR-409-3p can regulate the invasion and metastasis process of BC by targeting ZEB1 and may serve as a new prognostic marker and therapeutic target for treating BC metastasis. © 2016 IUBMB Life, 68(5):394-402, 2016.


Assuntos
Neoplasias da Mama/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/fisiologia , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Regiões 3' não Traduzidas , Adulto , Animais , Sequência de Bases , Sítios de Ligação , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Feminino , Expressão Gênica , Humanos , Metástase Linfática , Masculino , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Transplante de Neoplasias , Interferência de RNA , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
20.
Cell Physiol Biochem ; 36(6): 2263-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26279431

RESUMO

BACKGROUND/AIMS: MicroRNAs (miRNAs) have a key role in carcinogenesis and cancer development, but the role of miRNAs in the progression of esophageal cancer (EC) remains unclear. METHODS: The TE-1 and Eca-109 EC cell lines were used. The expression of miR-491 and candidate gene TPX2 in EC samples (n=99) were detected by RT-PCR. The cells invasive ability was determined by transwell assay. The luciferase reporter assay was used to confirm the regulation mechanism. RESULTS: A decreased expression of miR-491 was detected in the EC clinical samples compared with the corresponding adjacent tumor tissues. Aberrant expression of miR-491 regulated cells invasion and EMT markers. Furthermore, we verified that TPX2 was a target gene of miR-491. CONCLUSIONS: miR-491 may play a critical role in EC.


Assuntos
Proteínas de Ciclo Celular/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas Associadas aos Microtúbulos/genética , Proteínas Nucleares/genética , Idoso , Sequência de Bases , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Dados de Sequência Molecular , Invasividade Neoplásica , Proteínas Nucleares/metabolismo , RNA Interferente Pequeno/metabolismo
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