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1.
J Sci Food Agric ; 100(2): 551-559, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31587285

RESUMO

BACKGROUND: Phosphorylation is one of the most important post-translational modifications. Currently, many postmortem protein phosphorylation studies in muscle have been related to meat quality such as tenderness and color stability. However, the effects of various storage temperatures (25, 15, 4 and -1.5 °C) on the phosphorylation level of protein are poorly understood. Changes in the protein phosphorylation levels in postmortem ovine muscle at various storage temperatures were determined in this study. RESULTS: The obtained data showed that pH decline rate was significantly inhibited at -1.5 °C from 12 h to 7 days postmortem (P < 0.05). The ATP consumption rate was higher at 25 °C than that at other three temperatures (P < 0.05). Analysis of the temperature, pH and ATP content revealed that the ATP content was related to the phosphorylation levels of individual protein bands. Phosphorylated myofibrillar and sarcoplasmic proteins, such as myosin binding protein C, troponin T3, myosin light chain 1, glucose-6-phosphate isomerase and pyruvate kinase, were mainly involved in glycolysis and muscle contraction. CONCLUSION: The global and specific protein phosphorylation levels can be influenced by the postmortem storage temperature of muscle. Phosphorylation of proteins was correlated with glycolysis and muscle contraction. Certain phosphorylated proteins, such as heat shock proteins, require further study to clarify their effects on meat traits. © 2019 Society of Chemical Industry.


Assuntos
Armazenamento de Alimentos/métodos , Carne/análise , Proteínas Musculares/química , Músculo Esquelético/química , Animais , Armazenamento de Alimentos/instrumentação , Glicólise , Fosforilação , Mudanças Depois da Morte , Ovinos , Temperatura Ambiente
2.
Gut ; 69(1): 146-157, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30723104

RESUMO

OBJECTIVE: We explored the hypothesis that TGR5, the bile acid (BA) G-protein-coupled receptor highly expressed in biliary epithelial cells, protects the liver against BA overload through the regulation of biliary epithelium permeability. DESIGN: Experiments were performed under basal and TGR5 agonist treatment. In vitro transepithelial electric resistance (TER) and FITC-dextran diffusion were measured in different cell lines. In vivo FITC-dextran was injected in the gallbladder (GB) lumen and traced in plasma. Tight junction proteins and TGR5-induced signalling were investigated in vitro and in vivo (wild-type [WT] and TGR5-KO livers and GB). WT and TGR5-KO mice were submitted to bile duct ligation or alpha-naphtylisothiocyanate intoxication under vehicle or TGR5 agonist treatment, and liver injury was studied. RESULTS: In vitro TGR5 stimulation increased TER and reduced paracellular permeability for dextran. In vivo dextran diffusion after GB injection was increased in TGR5-knock-out (KO) as compared with WT mice and decreased on TGR5 stimulation. In TGR5-KO bile ducts and GB, junctional adhesion molecule A (JAM-A) was hypophosphorylated and selectively downregulated among TJP analysed. TGR5 stimulation induced JAM-A phosphorylation and stabilisation both in vitro and in vivo, associated with protein kinase C-ζ activation. TGR5 agonist-induced TER increase as well as JAM-A protein stabilisation was dependent on JAM-A Ser285 phosphorylation. TGR5 agonist-treated mice were protected from cholestasis-induced liver injury, and this protection was significantly impaired in JAM-A-KO mice. CONCLUSION: The BA receptor TGR5 regulates biliary epithelial barrier function in vitro and in vivo through an impact on JAM-A expression and phosphorylation, thereby protecting liver parenchyma against bile leakage.


Assuntos
Sistema Biliar/fisiopatologia , Colestase Intra-Hepática/prevenção & controle , Receptores Acoplados a Proteínas-G/fisiologia , Animais , Bile/metabolismo , Ácidos e Sais Biliares/metabolismo , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Colestase Intra-Hepática/metabolismo , Impedância Elétrica , Epitélio/fisiopatologia , Ácidos Isonipecóticos/farmacologia , Ácidos Isonipecóticos/uso terapêutico , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oximas/farmacologia , Oximas/uso terapêutico , Permeabilidade , Fosforilação/fisiologia , Receptores de Superfície Celular/metabolismo , Receptores Acoplados a Proteínas-G/agonistas , Transdução de Sinais/fisiologia , Proteínas de Junções Íntimas/metabolismo
3.
Nan Fang Yi Ke Da Xue Xue Bao ; 39(11): 1337-1343, 2019 Nov 30.
Artigo em Chinês | MEDLINE | ID: mdl-31852639

RESUMO

OBJECTIVE: To investigate the role of the protein-serine-threonine kinase (AKT)/glycogen synthase kinase 3ß (GSK3ß) signaling pathway in nicotinic acetylcholine receptors (nAChRs) aggregation disorder on skeletal muscle cell membranes induced by sepsis. METHODS: Mouse C2C12 myoblasts were differentiated into myotubes by horse serum, and then C2C12 myotubes were randomly divided into four groups: the Sham group treated with serum from sham-operated mice, the Sepsis group treated with serum from septic mice, the Sepsis+D group treated with serum from septic mice and dimethyl sulfoxide (DMSO), the Sepsis+SB group treated with serum from septic mice and GSK3ß inhibitor SB216763. Agrin was added into the cell culture to induce nAChRs aggregation before the treatment. After serum treatment for 5.5 h, the myotubes were examined for nAChRs clusters using Alexa Fluor 594-conjugated α-bungarotoxin (α- BTX). The expression levels of AKT, GSK3ß and CLIP- associated protein 2 (CLASP2) and the phosphorylation of AKT, GSK3ß were examined with Western blotting. The phosphorylation of CLASP2 and the interaction between CLASP2 and α-tubulin were detected with co-immunoprecipitation (Co-IP) assay. RESULTS: Compared with the serum from sham-operated mice, the serum from septic mice caused significant reduction in the area and density of nAChRs clusters on C2C12 myotubes, lowered the levels of phosphorylated AKT (p-AKT) and phosphorylated GSK3ß (p-GSK3ß), increased the expression of phosphorylated CLASP2 (p-CLASP2), and obviously reduced the binding between CLASP2 and α-tubulin. Compared with DMSO, SB216763 significantly increased the area and density of nAChRs clusters on C2C12 myotubes treated with serum from septic mice, decreased the expression of p-CLASP2, and enhanced the interaction between CLASP2 and α-tubulin. CONCLUSIONS: Septic mouse serum impairs nAChRs aggregation on C2C12 myotubes possibly by suppressing AKT/GSK3ß phosphorylation to cause reduced interaction between CLASP2 and α-tubulin.


Assuntos
Sepse , Animais , Membrana Celular , Glicogênio Sintase Quinase 3 beta , Camundongos , Proteínas Associadas aos Microtúbulos , Fibras Musculares Esqueléticas , Fosforilação , Proteínas Proto-Oncogênicas c-akt , Receptores Nicotínicos
4.
Georgian Med News ; (294): 128-131, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31687964

RESUMO

Histone modifications represent one of the types of epigenetic changes. Histones, undergo different types of epigenetic modifications, including the phosphorylation of serine residues. pHH3 antibodies specifically detect histon-3 protein, when phosphorylated at 10th and 28th serine residues. Traditionally pHH3 antibodies are used as proliferation marker, as it detects cells in late G2 and M phase. We studied the distribution of phosphor-histon-3 in epithelial tumors of the ovary and its relationship with ER, PR, Ki67, p53 and BCL2. Altogether, we investigated postoperative material from 160 patients. Standard immunohistochemistry was used to detect, phosphohistone-H3 (pHH3), ER, PR, Ki67, p53 and BCL2. The results of our study showed that phosphohistone-H3 expression is negatively associated with the expression of ER and PR expression, as well as with BCL2 expression, on the other hand it positively correlates with Ki67 and mutant p53 (p<0.05). In addition, the expression of phosphohistone-H3 is detected in Ki67 negative cases and its expression is increased along with the increase of malignancy grade. Our study results indicate that PHH3 might be used as an additional marker for the assessment of proliferation and malignancy potential of epithelial tumors of the ovary.


Assuntos
Epigênese Genética , Histonas/análise , Antígeno Ki-67/análise , Índice Mitótico/métodos , Gradação de Tumores/métodos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Fosforilação , Biomarcadores Tumorais , Proliferação de Células , Feminino , Humanos , Imuno-Histoquímica/métodos
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(5): 649-653, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31762232

RESUMO

OBJECTIVE: To investigate the molecular mechanism of apoptosis of HL60 cells induced by oncolytic virus Reovirus type 3 (Reo3). METHODS: HL60 cells were infected with Reo3 at different multiplicity of infection (MOI) with the uninfected HL60 cells as control group. After 48 h of infection, the activity of HL60 cells infected with virus at different MOI was detected by CCK8 method to investigate the influence of MOI to cell activity. Simultaneously, the apoptotic rate of HL60 cells was detected by flow cytometry, and the activation level of double-stranded RNA-dependent protein kinase (PKR) and the expression of apoptotic-related protein in HL60 cells were detected by Western blot. Before infection with Reo3 for 48 h, HL60 cells were treated with 2-aminopurine (2-AP), a specific inhibitor of PKR, for 24 h. Afterward, the apoptotic level and expression of apoptotic related proteins were detected. RESULTS: Activity of HL60 cells was obviously inhibited after infected with Reo3 with a MOI of 1 for 48 h. The cell survival rate was (24.333±3.396)% and the apoptotic rate was (29.96±2.06)%. Both rates were all higher than those in the control group (P < 0.05). Western blot results showed that the expression levels of PKR, p-PKR, Bax, Caspase3 and cleaved Caspase3 in HL60 cells infected with Reo3 were higher than those in the control group (P < 0.05), while the expression level of Bcl-2 was lower (P < 0.05). Compared with the group without inhibitor, the apoptotic rate of HL60 cells pretreated with 2-AP decreased (P < 0.05), the phosphorylation level of PKR and the expression level of apoptotic-related protein also decreased (P < 0.05). CONCLUSION: Oncolytic virus Reo3 could activate PKR in HL60 cells and thus induce apoptosis of HL60 cells.


Assuntos
Apoptose , Orthoreovirus Mamífero 3/fisiologia , eIF-2 Quinase/metabolismo , 2-Aminopurina/farmacologia , Caspase 3/metabolismo , Citometria de Fluxo , Células HL-60 , Humanos , Vírus Oncolíticos/fisiologia , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo
6.
Biol Res ; 52(1): 57, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31767027

RESUMO

BACKGROUND: Gastric cancer is a common malignant tumor with high morbidity and mortality worldwide, which seriously affects human health. Gramicidin is a short peptide antibiotic which could be used for treating infection induced by bacteria or fungi. However, the anti-cancer effect of gramicidin on gastric cancer cells and its underlying mechanism remains largely unknown. RESULTS: Gastric cancer cells SGC-7901, BGC-823 and normal gastric mucosal cells GES-1 were treated with different concentrations of gramicidin respectively. The results of CCK-8 experiment revealed cellular toxicity of gramicidin to cancer cells while cell colony formation assay showed that gramicidin significantly inhibited the proliferation of gastric cancer cells, but had little effect on normal gastric mucosal cells. In addition, the wound healing assay showed that gramicidin inhibited the migration of SGC-7901 cell. Meanwhile, apoptosis and cell cycle analysis revealed that gramicidin induced cell apoptosis with G2/M cell cycle inhibition. Furthermore, western blot analysis demonstrated that gramicidin down-regulated the expression of cyclinD1 and Bcl-2 as well as the FoxO1 phosphorylation. CONCLUSIONS: The current study illustrated the anti-tumor activity of gramicidin on gastric cancer cells, providing a possibility for gramicidin to be applied in clinical practice for the treatment of gastric cancer.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Gramicidina/farmacologia , Neoplasias Gástricas/patologia , Linhagem Celular Tumoral , Ciclina D1/efeitos dos fármacos , Ciclina D1/metabolismo , Regulação para Baixo , Proteína Forkhead Box O1/efeitos dos fármacos , Proteína Forkhead Box O1/metabolismo , Humanos , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
7.
Life Sci ; 237: 116944, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31604108

RESUMO

AIMS: Endoplasmic reticulum stress (ERS) is an evolutionarily conserved cell stress response. Recently, it was found that ERS induces not only apoptosis but also endoplasmic reticulophagy (ER-phagy). A previous study demonstrated that inhibition of ER-phagy alleviates cell injury. The purpose of this study was to investigate the involvement of the protein kinase R-like ER kinase (PERK)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in ERS-induced ER-phagy in H9c2 cardiomyoblasts. To address this aim, cells were treated with ERS inhibitors and a Nrf2 inhibitor before establishment of thapsigargin (TG)- or tunicamycin (TM)-induced ERS models in H9c2 cardiomyoblasts. MAIN METHODS: Transmission electron microscopy and immunofluorescence staining were used to detect ER-phagy. Western blotting was employed to detect the levels of calreticulin (CRT), total and phosphorylated PERK, nuclear Nrf2, activated transcription factor 4 (ATF4), light chain 3B (LC3B)-II and Beclin 1. Immunofluorescence staining was used to assess subcellular location of Nrf2. KEY FINDING: TG or TM induced H9c2 cell injury and ER-phagy and upregulated CRT expression, PERK phosphorylation, Nrf2 nuclear translocation, and expression of ATF4, Beclin 1, and LC3B-II compared with control cells. Treatment with ERS inhibitors decreased TG- or TM-induced ER-phagy, downregulated CRT expression, PERK phosphorylation, Nrf2 nuclear translocation and the expression of ATF4, Beclin 1 and LC3B-II. Moreover, a Nrf2 inhibitor downregulated the expression of ATF4, Beclin 1 and LC3B-II and alleviated TG- or TM-induced ER-phagy and H9c2 cell injury. SIGNIFICANCE: These findings suggest that the PERK/Nrf2 pathway mediates upregulation of ER-phagy, thereby inducing cell injury in H9c2 cardiomyoblasts.


Assuntos
Apoptose , Estresse do Retículo Endoplasmático , Retículo Endoplasmático/patologia , Miócitos Cardíacos/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , eIF-2 Quinase/metabolismo , Fator 4 Ativador da Transcrição/metabolismo , Animais , Proteína Beclina-1/metabolismo , Células Cultivadas , Retículo Endoplasmático/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Miócitos Cardíacos/metabolismo , Fosforilação , Ratos , Transdução de Sinais
8.
J Cancer Res Clin Oncol ; 145(12): 2921-2936, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31620898

RESUMO

PURPOSE: The present study aims to determine whether co-targeting PI3K/Akt and MAPK/ERK pathways in human hypopharyngeal squamous cell carcinoma (HSCC) is a potential anticancer strategy. METHODS: We retrospectively analyzed the clinical data of HSCC patients, and the phosphorylation status of Akt and Erk in HSCC and tumor adjacent tissues was evaluated by immunohistochemistry. MTT and colony formation assay were performed to determine the anti-proliferative effect of PI3K/mTOR inhibitor GDC-0980 and MEK inhibitor Refametinib on HSCC cell line Fadu. Wound-healing and Transwell migration assay were used to analyze the anti-migrative capability of the two drugs. The involved anti-tumor mechanism was explored by flow cytometry, qRT-PCR and western blot. The combinational anticancer effect of GDC-0980 and Refametinib was evaluated according to Chou and Talalay's method. RESULTS: The levels of p-Akt and p-Erk were increased significantly with the progression of clinical stage of HSCC, suggesting PI3K/Akt and MAPK/ERK pathways might be associated with HSCC occurrence and progression. Furthermore, both GDC-0980 and Refametinib showed obvious antitumor effects on FaDu cells. Treatment by the two drugs arrested FaDu cell cycle progression in G1 phase, with reduction of cyclin D1 and p-Rb, in contrast to enhancement of p27. GDC-0980 inhibited FaDu cell migration and reduced metastasis related proteins including p-PKCζ, p-Integrin ß1 and uPA. Combination use of GDC-0980 and Refametinib exhibited strong synergistic anti-tumor effect. CONCLUSION: Dual inhibition of PI3K/Akt and MAPK/ERK pathway by GDC-0980 and Refametinib might be a promising treatment strategy for HSCC patients.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Neoplasias Hipofaríngeas/tratamento farmacológico , Neoplasias Hipofaríngeas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Difenilamina/análogos & derivados , Difenilamina/farmacologia , Sinergismo Farmacológico , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Estudos Retrospectivos , Sulfonamidas/farmacologia
9.
Adv Exp Med Biol ; 1172: 207-226, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31628658

RESUMO

The NF-κB (Nuclear Factor kappa B) transcription factor plays crucial roles in the regulation of numerous biological processes including development of the immune system, inflammation, and innate and adaptive immune responses. Control over the immune cell functions of NF-κB results from signaling through one of two different routes: the canonical and noncanonical NF-κB signaling pathways. Present at the end of both pathways are the proteins NF-κB, IκB, and the IκB kinase (IKK). These proteins work together to deliver the myriad outcomes that influence context-dependent transcriptional control in immune cells. In the present chapter, we review the structural information available on NF-κB, IκB, and IKK, the critical terminal components of the NF-κB signaling, in relation to their physiological function.


Assuntos
Quinase I-kappa B , Proteínas I-kappa B , Sistema Imunitário , NF-kappa B , Transdução de Sinais , Animais , Humanos , Quinase I-kappa B/imunologia , Proteínas I-kappa B/imunologia , Sistema Imunitário/enzimologia , NF-kappa B/imunologia , Fosforilação , Transdução de Sinais/imunologia
10.
Int J Nanomedicine ; 14: 7475-7488, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571859

RESUMO

Background: Wear particle-induced inflammatory osteolysis and the consequent aseptic loosening constitute the leading reasons for prosthesis failure and revision surgery. Several studies have demonstrated that the macrophage polarization state and immune response play critical roles in periprosthetic osteolysis and tissue repair, but the immunomodulatory role of lithium chloride (LiCl), which has a protective effect on wear particle-induced osteolysis by suppressing osteoclasts and attenuating inflammatory responses, has never been investigated. Methods: In this work, the immunomodulatory capability of LiCl on titanium (Ti) nanoparticle-stimulated transformation of macrophage phenotypes and the subsequent effect on osteogenic differentiation were investigated. We first speculated that LiCl attenuated Ti nanoparticle-stimulated inflammation responses by driving macrophage polarization and generating an immune micro-environment to improve osteogenesis. Furthermore, a metal nanoparticle-stimulated murine air pouch inflammatory model was applied to confirm this protective effect in vivo. Results: The results revealed that metal nanoparticles significantly activate M1 phenotype (proinflammatory macrophage) expression and increase proinflammatory cytokines secretions in vitro and in vivo, whereas LiCl drives macrophages to the M2 phenotype (anti-inflammatory macrophage) and increases the release of anti-inflammatory and bone-related cytokines. This improved the osteogenic differentiation capability of rat bone marrow mesenchymal stem cells (rBMSCs). In addition, we also provided evidence that LiCl inhibits the phosphorylation of the p38 mitogen-activated protein kinase (p38) and extracellular signal-regulated kinase (ERK) pathways in wear particle-treated macrophages. Conclusion: LiCl has the immunomodulatory effects to alleviate Ti nanoparticle-mediated inflammatory reactions and enhance the osteogenic differentiation of rBMSCs by driving macrophage polarization. Thus, LiCl may be an effective therapeutic alternative for preventing and treating wear debris-induced inflammatory osteolysis.


Assuntos
Fatores Imunológicos/farmacologia , Inflamação/patologia , Cloreto de Lítio/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas Metálicas/química , Osteogênese/efeitos dos fármacos , Titânio/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Polaridade Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas Metálicas/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação/efeitos dos fármacos , Células RAW 264.7 , Ratos
11.
Photochem Photobiol Sci ; 18(11): 2740-2747, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573014

RESUMO

Cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB) is associated with memory formation and controls cell survival and proliferation via regulation of downstream gene expression in tumorigenesis. As a transcription factor, CREB binds to cAMP response elements. Phosphorylation of CREB triggers transcriptional activation of CREB downstream genes following the interaction of the kinase-inducible domain (KID) of CREB with the KID interaction domain (KIX) of CREB-binding protein. Nevertheless, because of the lack of single-cell analytical techniques, little is known about spatiotemporal regulation of CREB phosphorylation. To analyze CREB activation in single living cells, we developed genetically encoded bioluminescent sensors using luciferase-fragment complementation: the sensors are designed based on KID-KIX interaction with a single-molecule format. The luminescence intensity of the sensor, designated as CREX (a sensor of CREB activation based on KID(CREB)-KIX interaction), increased by phosphorylation of CREB. Moreover, the luminescence intensity of CREX was sufficient to detect CREB activation in live-cell bioluminescence imaging for single-cell analysis because of the higher sensitivity. CREX sensor is expected to contribute to elucidation of the spatiotemporal regulation of CREB phosphorylation by applying single-cell analysis.


Assuntos
Proteína de Ligação a CREB/análise , Medições Luminescentes/métodos , Proteína de Ligação a CREB/genética , Proteína de Ligação a CREB/metabolismo , Colforsina/química , Células HEK293 , Humanos , Luciferases/química , Luciferases/metabolismo , Fosforilação , Ligação Proteica , Domínios Proteicos/genética , Análise de Célula Única , Imagem com Lapso de Tempo
12.
Cell Physiol Biochem ; 53(4): 687-700, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31577078

RESUMO

BACKGROUND/AIMS: Apelin and its G protein-coupled receptor APJ (gene symbol Aplnr) are strongly expressed in magnocellular vasopressinergic neurons suggesting that the apelin/APJ system plays a key role at the central level in regulating salt and water balance by counteracting the antiduretic action of vasopressin (AVP). Likewise, recent studies revealed that apelin exerts opposite effects to those of vasopressin induced on water reabsorption via a direct action on the kidney collecting duct. However, the underlying mechanisms of the peripheral action of apelin are not clearly understood. Here, we thus investigated the role of the apelin/APJ system in the regulation of water balance in the kidney, and more specifically its involvement in modulating the function of aquaporin-2 (AQP2) in the collecting duct. METHODS: Mouse cortical collecting duct cells (mpkCCD) were incubated in the presence of dDAVP and treated with or without apelin-13. Changes in AQP2 expression and localization were determined by immunoblotting and confocal immunofluorescence staining. RESULTS: Herein, we showed that the APJ was present in mpkCCD cells. Treatment of mpkCCD with apelin-13 reduced the cAMP production and antagonized the AVP-induced increase in AQP2 mRNA and protein expressions. Immunofluorescent experiments also revealed that the AVP-induced apical cell surface expression of AQP2, and notably its phosphorylated isoform AQP2-pS269, was considerably reduced following apelin-13 application to mpkCCD cells. CONCLUSION: Our data reinforce the aquaretic role of the apelin/APJ system in the fine regulation of body fluid homeostasis at the kidney level and its physiological opposite action to the antiduretic activity of AVP.


Assuntos
Aquaporina 2/metabolismo , Desamino Arginina Vasopressina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Transporte Proteico/efeitos dos fármacos , Animais , Receptores de Apelina/metabolismo , Aquaporina 2/genética , Linhagem Celular , AMP Cíclico/metabolismo , Células HEK293 , Humanos , Túbulos Renais Coletores/citologia , Túbulos Renais Coletores/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos
13.
Anticancer Res ; 39(10): 5329-5338, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570426

RESUMO

BACKGROUND/AIM: The P13K/Akt signaling pathway is a growth-regulating cellular pathway that is constitutively activated in a variety of human cancers. In previous studies, we reported that a solenopsin analog, compound B (MU-06-SC-608-7), shows inhibitory effects on Akt phosphorylation at a key activation site, as well as on proliferation of tumorigenic cells at sub-micromolar concentrations. The purpose of this study was to evaluate the effect of compound B on downstream effectors of Akt kinase, phosphorylation of Akt at a second activation site, Akt kinase activity in vitro, tumorigenic cell viability and other signaling pathways. MATERIALS AND METHODS: Western blot analyses were performed using WBras1 epithelial and H2009 human carcinoma cells and cell viability assays were performed on H2009 cells. In vitro Akt kinase assays were performed using a commercially available kit. RESULTS: Compound B decreased the phosphorylation of Akt at the Thr308 activation site and key downstream effectors of Akt kinase, but did not directly inhibit Akt kinase. Substantial decreases in cell viability were observed at concentrations above 5 µM. No effect was seen on ERK or JNK pathways. CONCLUSION: The results earmark this compound for further studies as a potential targeted cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos
14.
Anticancer Res ; 39(10): 5483-5494, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570442

RESUMO

BACKGROUND/AIM: Canine mammary gland tumors (CMGTs) are the most common tumors in female dogs. Rivoceranib (also known as apatinib) is a novel anti-angiogenic tyrosine kinase inhibitor that selectively binds to vascular endothelial growth factor receptor-2 (VEGFR2). The aim of this study was to disclose the antitumor effects of rivoceranib on CMGT cell lines. MATERIALS AND METHODS: The direct effects of rivoceranib on CMGT cells in vitro were analyzed by cell proliferation and migration assays. Cell-cycle distribution and apoptotic ratio were analyzed by flow cytometry. Expression levels of phosphorylated VEGFR2 were evaluated by western blot analysis. RESULTS: Rivoceranib treatment significantly reduced the proliferation and migration of CMGT cells in a dose-dependent manner. Flow cytometry results revealed significant increases in G0/G1 phase arrest and apoptosis proportional to the drug concentration used. Rivoceranib reduced the level of phosphorylated VEGFR2. CONCLUSION: We confirm that rivoceranib exerts antitumor effects on CMGT cells by inhibiting biological functions.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Mamárias Animais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cães , Feminino , Fase G1/efeitos dos fármacos , Neoplasias Mamárias Animais/metabolismo , Fosforilação/efeitos dos fármacos , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
BMC Bioinformatics ; 20(1): 507, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31638911

RESUMO

BACKGROUND: Human tumor is a complex tissue with multiple heterogeneous hypoxic regions and significant cell-to-cell variability. Due to the complexity of the disease, the explanation of why anticancer therapies fail cannot be attributed to intrinsic or acquired drug resistance alone. Furthermore, there are inconsistent reports of hypoxia-induced kinase activities in different cancer cell-lines, where increase, decreases, or no change has been observed. Thus, we asked, why are there widely contrasting results in kinase activity under hypoxia in different cancer cell-lines and how does hypoxia play a role in anti-cancer drug sensitivity? RESULTS: We took a modeling approach to address these questions by analyzing the model simulation to explain why hypoxia driven signals can have dissimilar impact on tumor growth and alter the efficacy of anti-cancer drugs. Repeated simulations with varying concentrations of biomolecules followed by decision tree analysis reveal that the highly differential effects among heterogeneous subpopulation of tumor cells could be governed by varying concentrations of just a few key biomolecules. These biomolecules include activated serine/threonine-specific protein kinases (pRAF), mitogen-activated protein kinase kinase (pMEK), protein kinase B (pAkt), or phosphoinositide-4,5-bisphosphate 3-kinase (pPI3K). Additionally, the ratio of activated extracellular signal-regulated kinases (pERK) or pAkt to its respective total was a key factor in determining the sensitivity of pERK or pAkt to hypoxia. CONCLUSION: This work offers a mechanistic insight into how hypoxia can affect the efficacy of anti-cancer drug that targets tumor signaling and provides a framework to identify the types of tumor cells that are either sensitive or resistant to anti-cancer therapy.


Assuntos
Hipóxia/patologia , Neoplasias/patologia , Transdução de Sinais , Linhagem Celular Tumoral , Humanos , Sistema de Sinalização das MAP Quinases , Modelos Teóricos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinases raf/metabolismo
16.
Mol Biol (Mosk) ; 53(5): 838-848, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31661482

RESUMO

Lymphocyte phosphatase-associated phosphoprotein (LPAP) is a small transmembrane protein that is found in lymphocytes and is tightly associated with the phosphatase CD45. The function of LPAP is still unknown. Studies of the LPAP interactome may reveal new details of how C45 and lymphocyte signaling in general are regulated. LPAP binding partners were sought using coimmunoprecipitation coupled with mass spectrometry, stabilization of protein complexes with chemical crosslinkers, and Blue Native electrophoresis. In addition to CD45, several proteins were identified as LPAP partners, including CD71, CD98, cytoskeletal proteins, the amino acid transporter SLC1A4, and the cell signaling component HS1. It was confirmed that more than 70% of LPAP molecules were bound with CD45 in a 1 : 1 complex. The effect of CD45 on LPAP was studied in CEM and Jurkat cells with a CD45 knockout. The LPAP levels in the cells were 10% of the level in wild-type cells. In the absence of CD45, LPAP phosphorylation at Ser-153 and Ser-163 was not affected, whereas phosphorylation at Ser-99 and Ser-172 decreased significantly. Based on the results, CD45 was assumed to play a role in regulating LPAP expression and phosphorylation status.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ativação Linfocitária , Proteínas de Membrana/metabolismo , Mapas de Interação de Proteínas , Sistema ASC de Transporte de Aminoácidos/metabolismo , Antígenos CD/metabolismo , Proteína-1 Reguladora de Fusão/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Antígenos Comuns de Leucócito/metabolismo , Proteínas de Membrana/química , Fosforilação , Ligação Proteica , Receptores da Transferrina/metabolismo
17.
Medicine (Baltimore) ; 98(43): e17457, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31651849

RESUMO

The activity of p70S6 kinase located downstream of the mammalian target of rapamycin (mTOR) pathway is sensitive to mTOR inhibitors. However, the methods of assessing p70S6 kinase activity are still unclear. This study aimed to investigate p70S6 kinase activity in CD4-positive cells of liver transplant patients.Liver transplant patients treated with mTOR inhibitors were recruited from Beijing Chaoyang Hospital between October 2014 and October 2016. The influence of mycophenolic acid (MPA) derivatives and prednisone on p70S6 kinase phosphorylation in CD4-positive cells was examined in liver transplant patients and healthy controls (HCs). The phosphorylation of p70S6K in CD4 + CD25 regulatory T cells (Treg cells) and CD4 + CD25- T effector cells was analyzed by phospho-flow cytometry.The phospho-flow technique detected a significant loss of p70S6 kinase phosphorylation in CD4-positive cells of patients treated with mTOR inhibitors compared with HCs. MPA derivatives and prednisone did not affect p70S6 kinase phosphorylation significantly. No significant difference in p70S6 kinase phosphorylation was observed when the whole blood was stored within 3 hours at room temperature. The phosphorylation of p70S6K was significantly lower in CD4 + CD25 Treg cells than in CD4 + CD25-T effector cells in HCs. After liver transplant patients were treated with mTOR inhibitors, p70S6K phosphorylation was more reduced in CD4 + CD25-T effector cells than in CD4 + CD25 Treg cells.The presence of phosphorylation of p70S6 kinase in CD4-positive cells was reduced in liver transplant patients who were treated by mTOR inhibitors.


Assuntos
Linfócitos T CD4-Positivos/enzimologia , Inibidores Enzimáticos/farmacologia , Transplante de Fígado , Ácido Micofenólico/farmacologia , Fosforilação/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Resultado do Tratamento , Adulto Jovem
18.
Nature ; 574(7777): 249-253, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31578523

RESUMO

The integrity of the mammalian epidermis depends on a balance of proliferation and differentiation in the resident population of stem cells1. The kinase RIPK4 and the transcription factor IRF6 are mutated in severe developmental syndromes in humans, and mice lacking these genes display epidermal hyperproliferation and soft-tissue fusions that result in neonatal lethality2-5. Our understanding of how these genes control epidermal differentiation is incomplete. Here we show that the role of RIPK4 in mouse development requires its kinase activity; that RIPK4 and IRF6 expressed in the epidermis regulate the same biological processes; and that the phosphorylation of IRF6 at Ser413 and Ser424 primes IRF6 for activation. Using RNA sequencing (RNA-seq), histone chromatin immunoprecipitation followed by sequencing (ChIP-seq) and assay for transposase-accessible chromatin using sequencing (ATAC-seq) of skin in wild-type and IRF6-deficient mouse embryos, we define the transcriptional programs that are regulated by IRF6 during epidermal differentiation. IRF6 was enriched at bivalent promoters, and IRF6 deficiency caused defective expression of genes that are involved in the metabolism of lipids and the formation of tight junctions. Accordingly, the lipid composition of the stratum corneum of Irf6-/- skin was abnormal, culminating in a severe defect in the function of the epidermal barrier. Collectively, our results explain how RIPK4 and IRF6 function to ensure the integrity of the epidermis and provide mechanistic insights into why developmental syndromes that are characterized by orofacial, skin and genital abnormalities result when this axis goes awry.


Assuntos
Diferenciação Celular , Células Epidérmicas/citologia , Epiderme/fisiologia , Fatores Reguladores de Interferon/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Anormalidades Múltiplas/genética , Animais , Fenda Labial/genética , Fissura Palatina/genética , Cistos/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/embriologia , Embrião de Mamíferos/metabolismo , Células Epidérmicas/metabolismo , Epiderme/embriologia , Anormalidades do Olho/genética , Feminino , Dedos/anormalidades , Regulação da Expressão Gênica , Fatores Reguladores de Interferon/deficiência , Fatores Reguladores de Interferon/genética , Joelho/anormalidades , Articulação do Joelho/anormalidades , Lábio/anormalidades , Metabolismo dos Lipídeos/genética , Deformidades Congênitas das Extremidades Inferiores/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Fosfosserina/metabolismo , Proteínas Serina-Treonina Quinases/genética , Sindactilia/genética , Anormalidades Urogenitais/genética
19.
Wei Sheng Yan Jiu ; 48(4): 611-620, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31601344

RESUMO

OBJECTIVE: To investigate the effect of chronic and acute swimming exercise intervention on the mitogen-activated extracellular signal-regulated kinase(MEK) and extracellular signal-regulated kinase 1(ERK1) phosphorylation level in adipose tissues of obesityinduced insulin resistance rats. METHODS: A total of 100 SD rats were randomly divided into control group(n=10) fed with normal diet and high-fat diet group(n=90) fed with high fat diet. After 8 weeks, one third rats(n=30) with upper weight in high-fat diet group were selected and randomly divided into high-fat diet sedentary group(n=10), chronic exercise group(n=10) and acute exercise group(n=10). Under another 8-week high-fat diet feeding, exercise intervention was performed according to the exercise procedure; control group was fed with normal diet for 8 weeks. After exercise intervention, visceral adipose tissues were separated and MEK and ERK1 phosphorylation level in adipose tissue was detected by Western blot method. RESULTS: Chronic exercise intervention significantly reduced body weight, visceral fat weight and visceral fat weight/body weight ratio(P<0. 01), and acute exercise intervention had no significant effect on body weight, visceral fat weight and visceral fat weight/body weight ratio. Both chronic and acute exercise intervention significantly increased body insulin sensitivity(P<0. 05), as well as significantly decreased MEK and ERK1 phosphorylation level in adipose tissues(P<0. 01). CONCLUSION: The improvement of obesity-induced insulin resistance by exercise might be related to inhibited phosphorylation of MEK and ERK1 in adipose tissues.


Assuntos
Tecido Adiposo/metabolismo , Resistência à Insulina/fisiologia , MAP Quinase Quinase 1/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Condicionamento Físico Animal , Natação , Animais , Dieta Hiperlipídica , Insulina , Fosforilação , Ratos , Ratos Sprague-Dawley
20.
Chem Biol Interact ; 314: 108848, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610156

RESUMO

Cardiomyocyte injury induced by acute myocardial infarction contributes to myocardial dysfunction. Accumulating evidence has demonstrated that pleckstrin homology domain leucine-rich repeat protein phosphatase 2 (PHLPP2) is a cytoprotective protein that protects against various adverse injuries. However, whether PHLPP2 participates in regulating myocardial-infarction-induced cardiomyocyte injury remains unknown. In the present study, we aimed to investigate the biological role and molecular mechanism of PHLPP2 in regulating hypoxia-induced cardiomyocyte injury. Cardiomyocytes were cultured in an anaerobic chamber for 24 h to induce hypoxic injury in vitro. The expression of PHLPP2 was determined by real-time quantitative PCR and Western blot analysis. Cell viability was measured by MTT assay. Cell apoptosis was assessed by TUNEL and caspase-3 activity assays. Intracellular reactive oxygen species (ROS) levels were measured by DCFH-DA probe. PHLPP2 expression was highly upregulated in hypoxia-injured cardiomyocytes. Inhibition of PHLPP2 by small interfering RNA (siRNA)-mediated gene silencing significantly improved the viability of hypoxia-injured cardiomyocytes and attenuated hypoxia-induced apoptosis and ROS production. In contrast, PHLPP2 overexpression exacerbated hypoxia-induced apoptosis and ROS production in cardiomyocytes. Mechanism research revealed that PHLPP2 silencing increased the phosphorylation of glycogen synthase kinase (GSK)-3ß and promoted the nuclear translocation of nuclear factor (erythroid-derived 2)-like 2 (Nrf2). In addition, PHLPP2 inhibition promoted Nrf2/antioxidant response element (ARE) transcriptional activity. However, Nrf2 silencing markedly reversed PHLPP2-inhibition-mediated cardioprotection, while GSK-3ß inhibition partially blocked the PHLPP2-overexpression-induced adverse effect. Taken together, these findings demonstrate that PHLPP2 inhibition alleviates hypoxia-induced cardiomyocyte injury by reinforcing Nrf2/ARE antioxidant signaling via inactivating GSK-3ß, a pathway that highlights the importance of the PHLPP2/GSK-3ß/Nrf2/ARE signaling axis in regulation of cardiomyocyte injury. Our study suggests a potential relevance for PHLPP2 in acute myocardial infarction, and this protein may serve as a promising target for cardioprotection.


Assuntos
Elementos de Resposta Antioxidante/genética , Hipóxia Celular , Fator 2 Relacionado a NF-E2/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular , Regulação para Baixo , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/genética , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosfoproteínas Fosfatases/genética , Fosforilação , Pirimidinas/farmacologia , Pirróis/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
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