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1.
J Biol Chem ; 298(3): 101632, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35085551

RESUMO

Both the DNA damage response (DDR) and the mitotic checkpoint are critical for the maintenance of genomic stability. Among proteins involved in these processes, the ataxia-telangiectasia mutated (ATM) kinase is required for both activation of the DDR and the spindle assembly checkpoint (SAC). In mitosis without DNA damage, the enzymatic activity of ATM is enhanced; however, substrates of ATM in mitosis are unknown. Using stable isotope labeling of amino acids in cell culture mass spectrometry analysis, we identified a number of proteins that can potentially be phosphorylated by ATM during mitosis. This list is highly enriched in proteins involved in cell cycle regulation and the DDR. Among them, we further validated that ATM phosphorylated budding uninhibited by benzimidazoles 3 (Bub3), a major component of the SAC, on serine 135 (Ser135) both in vitro and in vivo. During mitosis, this phosphorylation promoted activation of another SAC component, benzimidazoles 1. Mutation of Bub3 Ser135 to alanine led to a defect in SAC activation. Furthermore, we found that ATM-mediated phosphorylation of Bub3 on Ser135 was also induced by ionizing radiation-induced DNA damage. However, this event resulted in independent signaling involving interaction with the Ku70-Ku80-DNA-PKcs sensor/kinase complex, leading to efficient nonhomologous end-joining repair. Taken together, we highlight the functional significance of the crosstalk between the kinetochore-oriented signal and double-strand break repair pathways via ATM phosphorylation of Bub3 on Ser135.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular , Dano ao DNA , Mitose , Proteínas de Ligação a Poli-ADP-Ribose , Fuso Acromático , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Benzimidazóis/farmacologia , Proteínas de Ciclo Celular/metabolismo , Humanos , Pontos de Checagem da Fase M do Ciclo Celular , Fosforilação , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Proteínas Serina-Treonina Quinases/genética , Serina/metabolismo , Fuso Acromático/metabolismo
2.
J Cell Mol Med ; 25(19): 9411-9426, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34453479

RESUMO

KCTD11 has been reported to be a potential tumour suppressor in several tumour types. However, the expression of KCTD11 and its role has not been reported in human non-small cell lung cancer (NSCLC). Whether its potential molecular mechanism is related to its BTB domain is also unknown. The expression of KCTD11 in 139 NSCLC tissue samples was detected by immunohistochemistry, and its correlation with clinicopathological factors was analysed. The effect of KCTD11 on the biological behaviour of lung cancer cells was verified in vitro and in vivo. Its effect on the epithelial-mesenchymal transition(EMT)process and the Wnt/ß-catenin and Hippo/YAP pathways were observed by Western blot, dual-luciferase assay, RT-qPCR, immunofluorescence and immunoprecipitation. KCTD11 is under-expressed in lung cancer tissues and cells and was negatively correlated with the degree of differentiation, tumour-node-metastasis (TNM) stage and lymph node metastasis. Low KCTD11 expression was associated with poor prognosis. KCTD11 overexpression inhibited the proliferation and migration of lung cancer cells. Further studies indicated that KCTD11 inhibited the Wnt pathway, activated the Hippo pathway and inhibited EMT processes by inhibiting the nuclear translocation of ß-catenin and YAP. KCTD11 lost its stimulatory effect on the Hippo pathway after knock down of ß-catenin. These findings confirm that KCTD11 inhibits ß-catenin and YAP nuclear translocation as well as the malignant phenotype of lung cancer cells by interacting with ß-catenin. This provides an important experimental basis for the interaction between KCTD11, ß-catenin and YAP, further revealing the link between the Wnt and Hippo pathways.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Via de Sinalização Hippo , Neoplasias Pulmonares/metabolismo , Transferases/metabolismo , Via de Sinalização Wnt , beta Catenina/metabolismo , Adulto , Idoso , Animais , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal/genética , Feminino , Expressão Gênica , Xenoenxertos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Fosforilação , Prognóstico , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Transporte Proteico , Fatores de Transcrição/metabolismo , Transferases/química , Transferases/genética
3.
Cancer Sci ; 112(10): 4064-4074, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34251713

RESUMO

Programmed cell death ligand 1 (PD-L1) is a major immunosuppressive checkpoint protein expressed by tumor cells to subvert anticancer immunity. Recent studies have shown that ionizing radiation (IR) upregulates the expression of PD-L1 in tumor cells. However, whether an IR-induced DNA damage response (DDR) directly regulates PD-L1 expression and the functional significance of its upregulation are not fully understood. Here, we show that IR-induced upregulation of PD-L1 expression proceeds through both transcriptional and post-translational mechanisms. Upregulated PD-L1 was predominantly present on the cell membrane, resulting in T-cell apoptosis in a co-culture system. Using mass spectrometry, we identified PD-L1 interacting proteins and found that BCLAF1 (Bcl2 associated transcription factor 1) is an important regulator of PD-L1 in response to IR. BCLAF1 depletion decreased PD-L1 expression by promoting the ubiquitination of PD-L1. In addition, we show that CMTM6 is upregulated in response to IR and participates in BCLAF1-dependent PD-L1 upregulation. Finally, we demonstrated that the ATM/BCLAF1/PD-L1 axis regulated PD-L1 stabilization in response to IR. Together, our findings reveal a novel regulatory mechanism of PD-L1 expression in the DDR.


Assuntos
Antígeno B7-H1/metabolismo , Radiação Ionizante , Proteínas Repressoras/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Apoptose , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Antígeno B7-H1/efeitos da radiação , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Técnicas de Cocultura , Dano ao DNA , Humanos , Células Jurkat , Proteínas com Domínio MARVEL/metabolismo , Proteínas com Domínio MARVEL/efeitos da radiação , Espectrometria de Massas , Proteínas da Mielina/metabolismo , Proteínas da Mielina/efeitos da radiação , Proteínas de Neoplasias/metabolismo , Modificação Traducional de Proteínas , Processamento de Proteína Pós-Traducional , Proteínas Repressoras/deficiência , Linfócitos T/citologia , Linfócitos T/efeitos da radiação , Proteínas Supressoras de Tumor/deficiência , Ubiquitinação , Regulação para Cima/efeitos da radiação
4.
Hepatology ; 71(4): 1421-1436, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31469186

RESUMO

BACKGROUND AND AIMS: STAT3, a member of the signal transducer and activator of transcription (STAT) family, is strongly associated with liver injury, inflammation, regeneration, and hepatocellular carcinoma development. However, the signals that regulate STAT3 activity are not completely understood. APPROACH AND RESULTS: Here we characterize CREB/ATF bZIP transcription factor CREBZF as a critical regulator of STAT3 in the hepatocyte to repress liver regeneration. We show that CREBZF deficiency stimulates the expression of the cyclin gene family and enhances liver regeneration after partial hepatectomy. Flow cytometry analysis reveals that CREBZF regulates cell cycle progression during liver regeneration in a hepatocyte-autonomous manner. Similar results were observed in another model of liver regeneration induced by intraperitoneal injection of carbon tetrachloride (CCl4 ). Mechanistically, CREBZF potently associates with the linker domain of STAT3 and represses its dimerization and transcriptional activity in vivo and in vitro. Importantly, hepatectomy-induced hyperactivation of cyclin D1 and liver regeneration in CREBZF liver-specific knockout mice was reversed by selective STAT3 inhibitor cucurbitacin I. In contrast, adeno-associated virus-mediated overexpression of CREBZF in the liver inhibits the expression of the cyclin gene family and attenuates liver regeneration in CCl4 -treated mice. CONCLUSIONS: These results characterize CREBZF as a coregulator of STAT3 to inhibit regenerative capacity, which may represent an essential cellular signal to maintain liver mass homeostasis. Therapeutic approaches to inhibit CREBZF may benefit the compromised liver during liver transplantation.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Regulação da Expressão Gênica , Regeneração Hepática/genética , Fígado/fisiologia , Fator de Transcrição STAT3/genética , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Tetracloreto de Carbono/toxicidade , Ciclo Celular/genética , Deleção de Genes , Hepatócitos/efeitos dos fármacos , Hepatócitos/fisiologia , Fígado/efeitos dos fármacos , Fígado/lesões , Redes e Vias Metabólicas , Camundongos , Camundongos Knockout
5.
Hepatology ; 68(4): 1361-1375, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29637572

RESUMO

Insulin is critical for the regulation of de novo fatty acid synthesis, which converts glucose to lipid in the liver. However, how insulin signals are transduced into the cell and then regulate lipogenesis remains to be fully understood. Here, we identified CREB/ATF bZIP transcription factor (CREBZF) of the activating transcription factor/cAMP response element-binding protein (ATF/CREB) gene family as a key regulator for lipogenesis through insulin-Akt signaling. Insulin-induced gene 2a (Insig-2a) decreases during refeeding, allowing sterol regulatory element binding protein 1c to be processed to promote lipogenesis; but the mechanism of reduction is unknown. We show that Insig-2a inhibition is mediated by insulin-induced CREBZF. CREBZF directly inhibits transcription of Insig-2a through association with activating transcription factor 4. Liver-specific knockout of CREBZF causes an induction of Insig-2a and Insig-1 and resulted in repressed lipogenic program in the liver of mice during refeeding or upon treatment with streptozotocin and insulin. Moreover, hepatic CREBZF deficiency attenuates hepatic steatosis in high-fat, high-sucrose diet-fed mice. Importantly, expression levels of CREBZF are increased in livers of diet-induced insulin resistance or genetically obese ob/ob mice and humans with hepatic steatosis, which may underscore the potential role of CREBZF in the development of sustained lipogenesis in the liver under selective insulin resistance conditions. CONCLUSION: These findings uncover an unexpected mechanism that couples changes in extracellular hormonal signals to hepatic lipid homeostasis; disrupting CREBZF function may have the therapeutic potential for treating fatty liver disease and insulin resistance. (Hepatology 2018).


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Fígado Gorduroso/patologia , Regulação da Expressão Gênica , Resistência à Insulina/genética , Lipogênese/genética , Análise de Variância , Animais , Biópsia por Agulha , Dieta Hiperlipídica , Modelos Animais de Doenças , Fígado Gorduroso/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Distribuição Aleatória , Transdução de Sinais
6.
Hepatology ; 64(2): 425-38, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26926384

RESUMO

UNLABELLED: Among the 22 fibroblast growth factors (FGFs), FGF21 has now emerged as a key metabolic regulator. However, the mechanism whereby FGF21 mediates its metabolic actions per se remains largely unknown. Here, we show that FGF21 represses mammalian target of rapamycin complex 1 (mTORC1) and improves insulin sensitivity and glycogen storage in a hepatocyte-autonomous manner. Administration of FGF21 in mice inhibits mTORC1 in the liver, whereas FGF21-deficient mice display pronounced insulin-stimulated mTORC1 activation and exacerbated hepatic insulin resistance (IR). FGF21 inhibits insulin- or nutrient-stimulated activation of mTORC1 to enhance phosphorylation of Akt in HepG2 cells at both normal and IR condition. TSC1 deficiency abrogates FGF21-mediated inhibition of mTORC1 and augmentation of insulin signaling and glycogen synthesis. Strikingly, hepatic ßKlotho knockdown or hepatic hyperactivation of mTORC1/ribosomal protein S6 kinase 1 abrogates hepatic insulin-sensitizing and glycemic-control effects of FGF21 in diet-induced insulin-resistant mice. Moreover, FGF21 improves methionine- and choline-deficient diet-induced steatohepatitis. CONCLUSIONS: FGF21 acts as an inhibitor of mTORC1 to control hepatic insulin action and maintain glucose homeostasis, and mTORC1 inhibition by FGF21 has the therapeutic potential for treating IR and type 2 diabetes. (Hepatology 2016;64:425-438).


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Resistência à Insulina , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Dieta Hiperlipídica , Glicogênio/biossíntese , Insulina/metabolismo , Proteínas Klotho , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sacarose
7.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(4): 341-4, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25919552

RESUMO

OBJECTIVE: To investigate the risk factors for early disseminated intravascular coagulation (DIC) in neonates with sepsis. METHODS: A retrospective clinical study was performed on 100 neonates with a confirmed diagnosis of sepsis between 2012 and 2013. The children were classified into normal coagulation group, non-overt DIC group (early DIC group), and overt DIC group (late DIC group) based on the ISTH overt DIC scoring system. The clinical manifestations and risk factors were analyzed statistically. RESULTS: Early DIC occurred in 44 (44%) cases in the 100 neonates with sepsis. The incidence of sclerema showed significant differences between the three groups (P<0.05). Asphyxia, bleeding, and Gram-negative bacterial infection were independent risk factors for early DIC. CONCLUSIONS: Coagulation function should be actively monitored and early intervention measures should be taken for neonates with asphyxia, bleeding, and Gram-negative bacterial infection to prevent early DIC from progressing to late DIC.


Assuntos
Coagulação Intravascular Disseminada/etiologia , Sepse/complicações , Feminino , Humanos , Recém-Nascido , Modelos Logísticos , Masculino , Fatores de Risco
8.
Cell Death Differ ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783090

RESUMO

The pseudokinase mixed lineage kinase domain-like (MLKL) is an essential component of the activation of the necroptotic pathway. Emerging evidence suggests that MLKL plays a key role in liver disease. However, how MLKL contributes to hepatocarcinogenesis has not been fully elucidated. Herein, we report that MLKL is upregulated in a diethylnitrosamine (DEN)-induced murine HCC model and is associated with human hepatocellular carcinomas. Hepatocyte-specific MLKL knockout suppresses the progression of hepatocarcinogenesis. Conversely, MLKL overexpression aggravates the initiation and progression of DEN-induced HCC. Mechanistic study reveals that deletion of MLKL significantly increases the activation of autophagy, thereby protecting against hepatocarcinogenesis. MLKL directly interacts with AMPKα1 and inhibits its activity independent of its necroptotic function. Mechanistically, MLKL serves as a bridging molecule between AMPKα1 and protein phosphatase 1B (PPM1B), thus enhancing the dephosphorylation of AMPKα1. Consistently, MLKL expression correlates negatively with AMPKα1 phosphorylation in HCC patients. Taken together, our findings highlight MLKL as a novel AMPK gatekeeper that plays key roles in inhibiting autophagy and driving hepatocarcinogenesis, suggesting that the MLKL-AMPKα1 axis is a potential therapeutic target for HCC.

9.
ACS Omega ; 8(45): 42678-42688, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38024676

RESUMO

The poly(methacrylic acid) (PMAA) polymer stabilized silver nanoclusters Agn (n = 2-9), synthesized in aqueous solution by the selected light wavelength irradiation photolysis approach, have been functionalized with thiol and amine ligands and successfully transferred from aqueous to organic media. Low- or high-resolution positive mass spectra showed constant species composites with the molecular formula AgnLn-1 [n = 2 to ∼9, L = butylmercaptan (C4H9S), thiolphenol (C6H5S), or dodecanethiol (C12H25S)] and proved that the molecules consist of deprotonated sulfur ligands in each species with one positive charge. Fourier transform infrared and X-ray photoelectron spectroscopy are consistent, indicating deprotonated sulfur, while silver has a zero valence value. The composition of the functionalized silver clusters is in agreement with that observed from polymer-wrapped "naked" silver clusters, which strongly indicates their real existence. For the silver cluster amine systems (heptylamine, dodecylamine, and oleylamine), only "naked" silver cluster species were detected from mass spectroscopy, similar to the polymer-wrapped case, indicating they are not stable enough in the gas phase. The development of a new antibacterial mask material is very important. The dodecylamine-capping silver nanoclusters were selected by coating the coffee filter surface to conduct antibacterial tests with Staphylococcus aureus and Escherichia coli, demonstrating very efficient antimicrobial properties even with organic capping ligands. Experiments also show that they work on mask material. One nanowire assembly with polystyrene and dodecylamine-capping silver nanoclusters was prepared, showing uniform nanofibers generated via the electrospray technique.

10.
Anal Methods ; 14(4): 401-409, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35006229

RESUMO

Herein, a poly(ionic liquid@MOF) composite monolithic column was prepared via in situ radical polymerization using ionic liquid (1-allyl-3-methylimidazolium hexafluorophosphate) and MOF (derivatized UIO66-2COOH) as copolymer monomers. The composite monolithic column was characterized via scanning electron microscopy (SEM), nitrogen adsorption-desorption isotherms and mercury intrusion porosimetry. Subsequently, the composite monolithic column combined with high performance liquid chromatography (HPLC) was used as a solid-phase extraction (SPE) absorbent for online purification and enrichment of tectochrysin in medicinal plants. The results indicated that the addition of the ionic liquid and MOF not only increased the surface area but also increased the adsorption capacity of the monolith for tectochrysin. The method showed good linearity in the concentration range of 0.01-500 µg mL-1. The calibration equation was y = 2154.6x - 8.3785 and the limit of detection (LOD, S/N = 3) and the limit of quantification (LOQ, S/N = 10) were 3.33 ng mL-1 and 10 ng mL-1, respectively. The relative standard deviation (RSD) of the intra-day and inter-day precision was less than 2.62%, the RSD of inter-column was less than 3.16%, and the recoveries ranged from 100.58% to 105.00%. Thus, results showed that this method is simple, accurate and convenient for the online enrichment and purification of tectochrysin from medicinal plants.


Assuntos
Líquidos Iônicos , Plantas Medicinais , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides , Líquidos Iônicos/química , Extração em Fase Sólida/métodos
11.
Int J Biol Sci ; 18(8): 3447-3457, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35637973

RESUMO

Protein palmitoylation is an increasingly investigated form of post-translational lipid modification that affects protein localization, accumulation, secretion and function. Recently, emerging findings have revealed that protein palmitoylation is crucial for many tumor-related signaling pathways, such as EGFR, RAS, PD-1/PD-L1 signaling, affecting the occurrence, progression and therapeutic response of tumors. Protein palmitoylation and its modifying enzymes, including palmitoylases and depalmitoylases, are expected to be new targets for effective tumor treatment. Recognizing the significance of palmitoylation modification on protein stability, localization and downstream signal regulation, this review focuses on the regulatory roles of protein palmitoylation and its modifying enzymes in tumor cell signal transduction, aiming to bring new ideas for effective cancer prevention and treatment.


Assuntos
Lipoilação , Neoplasias , Neoplasias/terapia , Processamento de Proteína Pós-Traducional , Transporte Proteico , Transdução de Sinais
12.
Onco Targets Ther ; 14: 2227-2233, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33824593

RESUMO

In adults, yolk sac tumors (YSTs) in the nasal cavity and paranasal sinuses are very rare. To date, only six cases have been reported in the English literature. YSTs in adults are often accompanied by cancer, teratocarcinosarcoma, and other malignant components. Here, we have reported a case of nasal tumor in a 55-year-old man with nasal obstruction and epistaxis. Morphologically, the tumor showed histological characteristics of pure YST. Immunohistochemical staining showed diffuse expression of SALL4, CDX2, and GPC-3 accompanied by sporadic expression of alpha-fetoprotein (AFP) and CD117. After 20 and 40 days of operation, the serum AFP level was 220.30 and 43.60 ng/mL (normal, <7 ng/mL), respectively, which supported the pathological diagnosis of YST. However, we further performed immunohistochemical staining and fluorescence in situ hybridization using an INI-1 probe to detect the status of INI-1 in tumor cells. The results revealed that INI-1 was absent in tumor cells. Hence, we corrected the diagnosis to SMARCB1 (INI-1)-deficient carcinoma of the nasal cavity with YST differentiation. The patient underwent surgery and adjuvant radiotherapy in our hospital without evidence of recurrence or metastasis at the 6-month follow-up. The serum AFP level had also normalized. In conclusion, our case demonstrates that INI-1-deficient carcinoma may exhibit, a pure YST differentiation and immunophenotype, and elevated serum AFP levels. In adults, YST in the nasal cavity may represent INI-1-deficient carcinoma, which may be a potential diagnostic pitfall.

13.
Cell Mol Gastroenterol Hepatol ; 12(3): 857-871, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33989817

RESUMO

BACKGROUND AND AIMS: Butyric acid is an intestinal microbiota-produced short-chain fatty acid, which exerts salutary effects on alleviating nonalcoholic fatty liver disease (NAFLD). However, the underlying mechanism of butyrate on regulating hepatic lipid metabolism is largely unexplored. METHODS: A mouse model of NAFLD was induced with high-fat diet feeding, and sodium butyrate (NaB) intervention was initiated at the eighth week and lasted for 8 weeks. Hepatic steatosis was evaluated and metabolic pathways concerning lipid homeostasis were analyzed. RESULTS: Here, we report that administration of NaB by gavage once daily for 8 weeks causes an augmentation of insulin-induced gene (Insig) activity and inhibition of lipogenic gene in mice fed with high-fat diet. Mechanistically, NaB is sufficient to enhance the interaction between Insig and its upstream kinase AMP-activated protein kinase (AMPK). The stimulatory effects of NaB on Insig-1 activity are abolished in AMPKα1/α2 double knockout (AMPK-/-) mouse primary hepatocytes. Moreover, AMPK activation by NaB is mediated by LKB1, as evidenced by the observations showing NaB-mediated induction of phosphorylation of AMPK, and its downstream target acetyl-CoA carboxylase is diminished in LKB1-/- mouse embryonic fibroblasts. CONCLUSIONS: These studies indicate that NaB serves as a negative regulator of hepatic lipogenesis in NAFLD and that NaB attenuates hepatic steatosis and improves lipid profile and liver function largely through the activation of LKB1-AMPK-Insig signaling pathway. Therefore, NaB has therapeutic potential for treating NAFLD and related metabolic diseases.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Ácido Butírico/farmacologia , Suplementos Nutricionais , Regulação da Expressão Gênica , Insulina/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Insulina/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Modelos Biológicos , Hepatopatia Gordurosa não Alcoólica/patologia , Fosforilação
14.
Artigo em Inglês | MEDLINE | ID: mdl-32905990

RESUMO

In this study, modified UiO-66-NH2 and N-methylolacrylamide (NMA) were used as common monomers to prepare a metal organic framework (MOF)-based composite monolith through in-situ polymerization, which was used as a new adsorbent to purify and enrich aristolochic acid-I (AA-I) in medicinal plants. The MOF-based composite monolithic column was characterized by nitrogen adsorption-desorption isotherm, mercury intrusion porosimetry and scanning electron microscopy (SEM). The adsorption ability of MOF-based composite monolith for AA-I was compared with that of the polymer monolith without MOF added. The results proved that the addition of UiO-66-NH2 can increase both the specific surface area and the permeability of the monolith. Moreover, the adsorption amount of AA-I on the monolith improved. This proposed on-line solid phase extraction (SPE) method showed good linear relationship in the range 0.044 ~ 400 µg/mL with r = 0.9994; the limit of detection (LOD) was 13.08 ng/mL and the limit of quantification (LOQ) was 44.00 ng/mL; the intra-day and inter-day accuracies were less than 0.97%; the inter-column accuracies was less than 6.11%; the recovery was in the range of 91.11%~106.48%. The method was found to be easy, accurate and convenient for on-line enrichment and purification of AA-I in medicinal plants.


Assuntos
Ácidos Aristolóquicos/análise , Estruturas Metalorgânicas/química , Plantas Medicinais/química , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Modelos Lineares , Reprodutibilidade dos Testes
15.
Front Oncol ; 10: 565414, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33364189

RESUMO

ZDHHC-protein acyltransferases (ZDHHCs) are a family of 23 signature Asp-His-His-Cys (DHHC) domain-containing enzymes that mediate palmitoylation by covalent attachment of the 16-carbon fatty acid palmitate to thiol groups of specific cysteine residues in substrate proteins. Emerging evidence has shown abnormal expression of ZDHHCs in a variety of disease states, including cancer. Kidney renal clear cell carcinoma (KIRC) is the eighth most common type of cancer, which accounts for the majority of malignant kidney tumors. However, there are currently no effective therapeutic targets or biomarkers for clinical treatment and prognosis in KIRC. In this study, we first analyzed the expression pattern of the 23 ZDHHCs in KIRC using TCGA and GEPIA database, and found that the expression of ZDHHC2, 3, 6, 14, 15, 21, and 23 was significantly down-regulated whereas the expression of ZDHHC9, 17, 18, 19 and 20 was significantly up-regulated in KIRC patient tissues vs. normal tissues. And the expression of ZDHHC2, 3, 6, 9, 14, 15, and 21 in tumors decreased with the increase of the pathological stage of KIRC patients. Notably, KIRC patients with decreased expression of ZDHHC3, 6, 9, 14, 15, 17, 20, 21, 23 and increased expression of ZDHHC19 were significantly associated with poor prognosis. Further, we found that there was a significant correlation between ZDHHC3, 6, 9, 14, 15, 17, 19, 20, 21, 23 expressions and immune cell infiltration. Besides, high mRNA expression was the most common type of gene alteration and there was a high correlation among the expression of ZDHHC6, 17, 20 and 21. Finally, function prediction indicated that the immune or metabolic disorders or the activation of oncogenic signaling pathways caused by abnormal expression of these ZDHHCs may be important mechanisms of tumor progression and poor prognosis in patients with KIRC. Our results may provide novel insight for identifying tumor markers or molecular targets for the treatment of KIRC.

16.
Cancer Biol Med ; 17(3): 640-651, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32944396

RESUMO

Objective: Mitotic arrest-deficient protein 1 (MAD1) is a kinetochore protein essential for the mitotic spindle checkpoint. Proteomic studies have indicated that MAD1 is a component of the DNA damage response (DDR) pathway. However, whether and how MAD1 might be directly involved in the DDR is largely unknown. Methods: We ectopically expressed the wild type, or a phosphorylation-site--mutated form of MAD1 in MAD1 knockdown cells to look for complementation effects. We used the comet assay, colony formation assay, immunofluorescence staining, and flow cytometry to assess the DDR, radiosensitivity, and the G2/M checkpoint. We employed co-immunoprecipitation followed by mass spectrometry to identify MAD1 interacting proteins. Data were analyzed using the unpaired Student's t-test. Results: We showed that MAD1 was required for an optimal DDR, as knocking down MAD1 resulted in impaired DNA repair and hypersensitivity to ionizing radiation (IR). We found that IR-induced serine 214 phosphorylation was ataxia-telangiectasia mutated (ATM) kinase-dependent. Mutation of serine 214 to alanine failed to rescue the phenotypes of MAD1 knockdown cells in response to IR. Using mass spectrometry, we identified a protein complex mediated by MAD1 serine 214 phosphorylation in response to IR. Among them, we showed that KU80 was a key protein that displayed enhanced interaction with MAD1 after DNA damage. Finally, we showed that MAD1 interaction with KU80 required serine 214 phosphorylation, and it was essential for activation of DNA protein kinases catalytic subunit (DNA-PKcs). Conclusions: MAD1 serine 214 phosphorylation mediated by ATM kinase in response to IR was required for the interaction with KU80 and activation of DNA-PKCs.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/deficiência , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA/genética , Proteína Quinase Ativada por DNA/metabolismo , Autoantígeno Ku/metabolismo , Animais , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Dano ao DNA/efeitos da radiação , Proteína Quinase Ativada por DNA/genética , Feminino , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HCT116 , Células HeLa , Humanos , Autoantígeno Ku/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Fosforilação , Tolerância a Radiação/genética , Radiação Ionizante , Ensaios Antitumorais Modelo de Xenoenxerto
17.
EBioMedicine ; 57: 102849, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32580141

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is associated with altered production of secreted proteins. Increased understanding of secreted proteins could lead to improved prediction and treatment of NAFLD. Here, we aimed to discover novel secreted proteins in humans that are associated with hepatic fat content using unbiased proteomic profiling strategy, and how the identified Thbs1 modulates lipid metabolism and hepatic steatosis. METHOD: NAFLD patients were enrolled and treated with lifestyle intervention. Patients who underwent liver biopsy were enrolled for analyzing the correlation between circulating Thbs1 and liver steatosis. Mice were fed on high-fat, high-sucrose diet and treated with recombinant Thbs1. Primary hepatocytes isolated from CD36 knockout (CD36-/-) mice and their wild-type littermates (controls) were treated with glucose plus insulin for 24 h together with or without recombinant Thbs1. FINDING: Serum Thbs1 levels are increased in participants with NAFLD and positively associated with liver steatosis grades. Improvement of liver steatosis after lifestyle intervention was accompanied with significant reduction of serum Thbs1 levels. Pharmacological administration of recombinant human Thbs1 attenuates hepatic steatosis in diet-induced obese mice. Treatment with Thbs1 protein or stably overexpression of Thbs1 causes a significant reduction of lipid accumulation in primary hepatocytes or HepG2 cells exposed to high glucose plus insulin, suggesting that Thbs1 regulates lipid metabolism in a hepatocyte-autonomous manner. Mechanistically, Thbs1 inhibits cleavage and processing of SREBP-1, leading to a reduction of target lipogenic gene expression and hepatic steatosis. Inhibitory effects of Thbs1 on lipogenesis and triglyceride accumulation are abrogated in CD36 deficient primary hepatocytes exposed to high glucose plus insulin. Interestingly, beneficial effects of Thbs1 on lipid accumulation are observed in primary hepatocytes treated with a Thbs1 nonapeptide mimetic ABT-526. INTERPRETATION: Thbs1 is a biomarker for NAFLD in humans, and pharmacological and genetic approaches for the modulation of Thbs1 activity may have the therapeutic potential for treating hepatic steatosis. FUND: A full list of funding bodies that contributed to this study can be found in the Funding Sources section.


Assuntos
Fígado Gorduroso/genética , Metabolismo dos Lipídeos/genética , Hepatopatia Gordurosa não Alcoólica/genética , Proteômica , Trombospondina 1/genética , Animais , Antígenos CD36/genética , Dieta Hiperlipídica/efeitos adversos , Fígado Gorduroso/dietoterapia , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Insulina/genética , Insulina/metabolismo , Resistência à Insulina/genética , Lipogênese/genética , Fígado/metabolismo , Fígado/patologia , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/dietoterapia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Fragmentos de Peptídeos/farmacologia , Trombospondina 1/farmacologia , Triglicerídeos/sangue
19.
Exp Ther Med ; 18(6): 4322-4328, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31777539

RESUMO

To observe the effect of probiotics on the stress responses and intestinal permeability of term neonates with low Apgar scores, the present study retrospectively analyzed the clinical data of 78 term neonates (42 males and 36 females). In the control group (n=38), total parenteral nutrition and comprehensive treatment (anti-infection therapy) were provided. In the observation group (n=40), the neonates were administered Lactobacillus Complex Capsules in addition to the control group treatment. The corticotropin-releasing factor level was determined using ELISA; cortisol levels were determined using a radioimmunoprecipitation assay; D-lactate and diamine oxidase levels were determined using ultraviolet spectrometry; procalcitonin levels were determined using ECL; and C-reactive protein levels were determined using a protein analyzer. Following treatment, the levels of all parameters were lower in the observation group compared with the control group, and the differences were statistically significant (P<0.05). In the observation group, the daily milk intake was 16.57±2.58 ml, which was significantly higher than that of the control group (13.26±1.87 ml), while the length of hospital stay and total parenteral nutrition time, which were 12.31±2.02 and 6.21±1.26 days, respectively, in the observation group, were significantly shorter than those of the control group (14.86±2.58 and 8.86±1.78 days, respectively), and the differences were statistically significant (P<0.001). The results of the present study suggested that probiotics can ameliorate the stress response and intestinal permeability of term neonates with low Apgar scores, thereby, facilitating gastrointestinal function recovery.

20.
Int J Clin Exp Pathol ; 12(4): 1118-1123, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31933927

RESUMO

Pleomorphic xanthoastrocytoma (PXA) is a relatively rare, low grade astrocytic tumor that usually affects children as well as young adults. The reported cases were predominantly located superficially in the temporal lobe. To our knowledge, so far only two cases of PXA occurring in lateral ventricle were reported in English literature. Herein, we present the third case of PXA intra-lateral ventricle in a 28-year-old Chinese male. Histologically, the tumor was relatively well circumscribed and consisted of spindle-shaped, ovoid, and multinuclear giant cells admixed with scattered eosinophilic granular bodies, inflammatory cells, and xanthomatous cells. Immunohistochemically, the tumor cells were strongly positive for S-100, GFAP, oligo-2 and vimentin, focally positive for synaptophysin and CD34, and negative for cytokeratin, EMA, NeuN and IDH1. Ki-67 proliferation index was approximately 2%. A BRAF V600E mutation was then identified in the tumor. Based on morphologic features, the immunohistochemical staining and BRAF V600E mutation, the tumor was diagnosed as a PXA. Because of the presence of the bizarre multinuclear giant cells and xanthomatous cells and the unusual location, PXA was easily misdiagnosed as a high-grade tumor. It should be noted that PXA was also an important differential diagnosis for intraventricular tumors.

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