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1.
Food Chem ; 415: 135733, 2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-36854241

RESUMO

Peanut protein is a common food allergen. Our previous study demonstrated that the allergenicity of Ara h1 declines after covalent conjugation with polyphenols in vitro; however, how polyphenols affect the structure, function, and allergenicity of peanut protein extract (PPE) after covalent conjugating needs clarifying. Here, we assessed how the structure, function, and allergenicity of PPE changed after covalent conjugation with epigallocatechin-3-gallate (PPE-EGCG) and chlorogenic acid (PPE-CA). PPE covalently conjugated with EGCG and CA using the alkali treatment method. Multi-spectroscopy showed that the structure of PPE-EGCG/CA conjugate changed, becoming less folded. In contrast, the functional properties of PPE significantly improved. The allergenicity of PPE-EGCG/CA significantly declined in vitro and in vivo experiments. Our findings confirm that covalent conjugation of PPE with EGCG and CA reduces the allergenicity and improves the functional properties of PPE by changing the structure of the protein.


Assuntos
Catequina , Polifenóis , Polifenóis/metabolismo , Arachis/química , Alérgenos/química , Proteínas de Plantas/metabolismo , Ácido Clorogênico/química , Catequina/química
2.
J Chem Inf Model ; 63(3): 835-845, 2023 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-36724090

RESUMO

Many bioactive peptides demonstrated therapeutic effects over complicated diseases, such as antiviral, antibacterial, anticancer, etc. It is possible to generate a large number of potentially bioactive peptides using deep learning in a manner analogous to the generation of de novo chemical compounds using the acquired bioactive peptides as a training set. Such generative techniques would be significant for drug development since peptides are much easier and cheaper to synthesize than compounds. Despite the limited availability of deep learning-based peptide-generating models, we have built an LSTM model (called LSTM_Pep) to generate de novo peptides and fine-tuned the model to generate de novo peptides with specific prospective therapeutic benefits. Remarkably, the Antimicrobial Peptide Database has been effectively utilized to generate various kinds of potential active de novo peptides. We proposed a pipeline for screening those generated peptides for a given target and used the main protease of SARS-COV-2 as a proof-of-concept. Moreover, we have developed a deep learning-based protein-peptide prediction model (DeepPep) for rapid screening of the generated peptides for the given targets. Together with the generating model, we have demonstrated that iteratively fine-tuning training, generating, and screening peptides for higher-predicted binding affinity peptides can be achieved. Our work sheds light on developing deep learning-based methods and pipelines to effectively generate and obtain bioactive peptides with a specific therapeutic effect and showcases how artificial intelligence can help discover de novo bioactive peptides that can bind to a particular target.


Assuntos
COVID-19 , Aprendizado Profundo , Humanos , Inteligência Artificial , Desenho de Fármacos , SARS-CoV-2 , Peptídeos/farmacologia
3.
Foods ; 11(15)2022 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-35954133

RESUMO

The proliferation inhibition effects of the hydrolysates from silkworm pupa proteins on MGC-803 gastric cancer cells were investigated in this study. The specific morphological changes (cell membrane, cell nucleus and cytoskeleton) of cells were measured. In vitro, the proliferation of MGC-803 cells was inhibited by silkworm pupa protein hydrolysates (SPPHs) in a dose-dependent manner. The flow cytometry analysis showed that the blocking effect of SPPHs on the MGC-803 cells was mainly in the G0/G1-phase. The morphological changes, disintegration of the cytoskeleton and retardant cell cycles were probably related to the activation of apoptosis. Thus, SPPHs could be promising as a chemopreventive agent due to their ability to promote apoptosis of tumor cells.

4.
Food Chem ; 373(Pt B): 131589, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34801286

RESUMO

The 7S fraction contains several major allergens of soybean protein. Here, the effects of covalent modification by chlorogenic acid (CHA) and (-)-epigallo-catechin 3-gallate (EGCG) on the allergenicity and functional properties of soybean 7S protein were investigated. Conjugation with EGCG and CHA resulted in the formation of cross-linked protein polymers and changes to the structures of the protein, which might mask or destroy the epitopes on it. In vitro analysis revealed that modification by polyphenols noticeably reduced IgE binding activity and histamine release. In vivo analysis showed that modification led to milder anaphylactic shock symptoms and minor damage of the intestine in mice, with reducing IgG, IgE, IgG1, mMCP-1, and histamine levels. The allergic response was also suppressed by the repression of IFN-γ, IL-4, and IL-5 and the up-regulation of IL-10 and TGF-ß in the conjugate groups. Furthermore, modification enhanced antioxidant, emulsion, foaming capacity, and foam stability of the protein.


Assuntos
Alérgenos , Polifenóis , Animais , Imunoglobulina E , Camundongos , Proteínas de Soja , Glycine max
5.
J Agric Food Chem ; 69(22): 6291-6302, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34033464

RESUMO

The impact of covalent attachment of (-)-epigallocatechin gallate (EGCG) to lactoferrin (LF) on the structure, morphology, functionality, and allergenicity of the protein was studied. These polyphenol-protein conjugates were formed using various enzymatic (laccase- and tyrosinase-catalyzed oxidation) and nonenzymatic (free radical grafting and alkali treatment) methods. The preparation conditions for forming the enzymatic conjugates were optimized by exploring the influence of order-of-addition effects: protein, polyphenols, and enzymes. The total phenol content of the LF-EGCG conjugates was quantified using the Folin-Ciocalteu method. The nature of the conjugates formed was determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared (FTIR) spectroscopy analyses. These studies showed that enzymatic cross-linking was a highly effective means of forming LF-EGCG conjugates. Analysis of these conjugates using various spectroscopic methods showed that conjugation to EGCG changed the molecular structure of LF. Atomic force microscopy showed that the four covalent cross-linking methods affected the size and morphology of these LF-EGCG conjugates formed. The antioxidant activity and emulsifying stability of LF were significantly improved by conjugation to EGCG. Finally, an enzyme-linked immunosorbent assay (ELISA) and a western blot assay indicated that conjugation of EGCG reduced the binding capacity of LF to immunoglobulin E (IgE) and immunoglobulin G (IgG), which is consistent with a decrease in allergenicity. Overall, this study suggests that LF-EGCG conjugates formed using enzymatic or nonenzymatic methods have potential applications as functional ingredients in foods.


Assuntos
Alérgenos , Catequina , Catequina/análogos & derivados , Lactoferrina , Polifenóis
6.
Food Res Int ; 140: 109997, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33648231

RESUMO

Here, the potential allergenicity of shrimp tropomyosin (TM) after conjugation with chlorogenic acid (CA) and (-)-epigallo-catechin 3-gallate (EGCG) was assessed. Conformational structures of TM-polyphenol complexes were detected using SDS-PAGE, circular dichroism (CD), and fluorescence. Potential allergenicity was assessed by immunological methods, a rat basophil leukemia cell model (RBL-2H3), and in vivo assays. Indirect ELISA showed that TM-polyphenol complexes caused a conformational change to TM structure, with decreased IgG/IgE binding capacity significantly fewer inflammatory mediators were released with EGCG-TM and CA-TM in a mediator-releasing RBL-2H3 cell line. Mice model showed low allergenicity to serum levels of TM-specific antibody and T-cell cytokine production. EGCG-TM and CA-TM might reduce the potential allergenicity of shrimp TM, which could be used to produce hypoallergenic food in the food industry.


Assuntos
Penaeidae , Tropomiosina , Alérgenos , Animais , Imunoglobulina E , Camundongos , Polifenóis , Ratos
7.
Food Chem ; 331: 127355, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-32593042

RESUMO

Ara h1 is a major allergen from peanut. We investigated the effect of covalent conjugation of Ara h1 and dietary polyphenols on allergenicity and functional properties of Ara h1. Enzyme-linked immunosorbent assay revealed that the covalent conjugation of dietary polyphenols significantly reduced the IgE binding capacity of Ara h1. Covalent binding of dietary polyphenols with Ara h1 reduced histamine release by 40% in basophils. The decreased IgE binding capacity of Ara h1 could be ascribed to changes in protein conformation. The IgE epitope of Ara h1 might be blocked by polyphenols at the binding site. Analysis of pepsin digestion of Ara h1-polyphenol conjugates indicated that the covalent binding increased pepsin digestibility and reduced IgE binding capacity. Furthermore, covalent conjugation of Ara h1 with polyphenols decreased denaturation temperature and increased antioxidant activity. Ara h1 conjugated with polyphenols may be a promising approach for reducing the allergenicity of Ara h1.


Assuntos
Antígenos de Plantas/química , Antígenos de Plantas/imunologia , Catequina/análogos & derivados , Ácido Clorogênico/química , Proteínas de Membrana/química , Proteínas de Membrana/imunologia , Hipersensibilidade a Amendoim/imunologia , Proteínas de Plantas/química , Proteínas de Plantas/imunologia , Antígenos de Plantas/farmacologia , Antioxidantes/química , Arachis/química , Basófilos/efeitos dos fármacos , Basófilos/imunologia , Basófilos/metabolismo , Catequina/química , Catequina/imunologia , Catequina/metabolismo , Epitopos/metabolismo , Histamina/metabolismo , Humanos , Imunoglobulina E/metabolismo , Proteínas de Membrana/farmacologia , Proteínas de Plantas/farmacologia , Conformação Proteica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier
8.
J Agric Food Chem ; 68(13): 4027-4035, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32182051

RESUMO

A previous study demonstrated decreased allergenicity in vitro of some food allergens after conjugation with polyphenols. However, little is known about how polyphenol conjugation with food allergens affects in vivo allergenicity. We conjugated a well-known food allergen, ovalbumin (OVA), with quercetin (QUE) to assess the potential allergenicity of OVA in vitro and in vivo in a BALB/c mouse model. QUE could covalently conjugate with OVA and changed the protein structure, which might destroy and/or mask OVA epitopes. Conjugation with QUE decreased IgE binding properties and the release capacity of the conjugated OVA. In vivo, as compared with native protein, conjugation with QUE decreased the levels of IgE, IgG1, IgG, plasma histamine, and mast cell protease-1 (mMCP-1) on the surface of sensitized mast cells, along with decreased FcεRI+ and c-kit+ expression. The levels of Th2-related cytokines (IL-4, IL-5, IL-13) decreased and that of a Th1-related cytokine (IFN-γ) increased slightly, which suggests that conjugation with QUE modulated the imbalance of the Th1/Th2 immune response. Conjugation of OVA with QUE could reduce OVA allergenicity in vitro and in vivo, which could provide information for reducing food allergenicity by conjugation with polyphenols.


Assuntos
Alérgenos/imunologia , Hipersensibilidade Alimentar/imunologia , Ovalbumina/imunologia , Quercetina/química , Alérgenos/química , Animais , Citocinas/imunologia , Humanos , Imunoglobulina E/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/química , Conformação Proteica , Células Th1/imunologia , Células Th2/imunologia
9.
Food Funct ; 11(2): 1525-1536, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31995080

RESUMO

Resveratrol (RES)-loaded protein-polysaccharide nanoparticles were fabricated through simple electrostatic interactions with oppositely charged α-lactalbumin (ALA) and chitosan (CHI) with a mass ratio of 5 : 1 without the addition of NaCl at pH 6.5. The Z-average diameter and zeta-potential values of RES-ALA-CHI nanoparticles were 211.0 nm and 13.23 mV, respectively. Both TEM and AFM graphs confirmed that RES-ALA-CHI nanoparticles had a spherical shape, and were dispersed homogeneously at the nanoscale. The encapsulation efficiency (EE) and loading amount (LA) of RES in RES-ALA-CHI nanoparticles were 58.86% and 196.2 µg mg-1, respectively, in the presence of 400 µg mL-1 RES. XRD results confirmed that RES was in amorphous form in ALA-CHI nanoparticles. The interaction between RES and ALA-CHI nanoparticles was mainly driven by hydrophobic interaction and hydrogen bonding. Compared to RES (free), the UV light and heat stability, in vitro bioaccessibility, and antioxidant activity of RES in RES-ALA-CHI nanoparticles were pronouncedly enhanced. The information provided in this study should be of interest to the food industry to fabricate robust nanoscale delivery systems with ALA-CHI nanoparticles for RES and other hydrophobic bioactive compounds.


Assuntos
Antioxidantes , Quitosana/química , Lactalbumina/química , Nanopartículas/química , Resveratrol , Antioxidantes/química , Antioxidantes/metabolismo , Compostos de Bifenilo/química , Compostos de Bifenilo/metabolismo , Portadores de Fármacos/química , Estabilidade de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Picratos/química , Picratos/metabolismo , Resveratrol/química , Resveratrol/metabolismo
10.
Sci Adv ; 5(3): eaav5078, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30906869

RESUMO

Defective nuclear lamina protein lamin A is associated with premature aging. Casein kinase 2 (CK2) binds the nuclear lamina, and inhibiting CK2 activity induces cellular senescence in cancer cells. Thus, it is feasible that lamin A and CK2 may cooperate in the aging process. Nuclear CK2 localization relies on lamin A and the lamin A carboxyl terminus physically interacts with the CK2α catalytic core and inhibits its kinase activity. Loss of lamin A in Lmna-knockout mouse embryonic fibroblasts (MEFs) confers increased CK2 activity. Conversely, prelamin A that accumulates in Zmpste24-deficent MEFs exhibits a high CK2α binding affinity and concomitantly reduces CK2 kinase activity. Permidine treatment activates CK2 by releasing the interaction between lamin A and CK2, promoting DNA damage repair and ameliorating progeroid features. These data reveal a previously unidentified function for nuclear lamin A and highlight an essential role for CK2 in regulating senescence and aging.


Assuntos
Envelhecimento/genética , Caseína Quinase II/genética , Lamina Tipo A/genética , Proteínas de Membrana/genética , Metaloendopeptidases/genética , Progéria/genética , Envelhecimento/efeitos dos fármacos , Envelhecimento/patologia , Animais , Caseína Quinase II/química , Núcleo Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Dano ao DNA/genética , Reparo do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Fibroblastos/efeitos dos fármacos , Humanos , Lamina Tipo A/química , Camundongos , Camundongos Knockout , Progéria/tratamento farmacológico , Progéria/patologia , Ligação Proteica/genética , Espermidina/farmacologia
11.
Food Chem ; 281: 28-35, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-30658758

RESUMO

Anthraquinones, a class of naturally occurring polyphenolic compounds, exhibit a wide range of bioactivities. However, most free anthraquinones are lipophilic bioactive compounds. Bovine ß-lactoglobulin (ßLG), a major whey protein, has a high affinity for small hydrophobic compounds. In this study, the interactions between anthraquinones (rhein, emodin, and chrysophanol) and ßLG were investigated by using fluorescence, circular dichroism (CD), Fourier-transform infrared spectroscopy (FTIR), and docking studies. These anthraquinones bound to the site near Trp19-Arg124 on ßLG with a binding constant (Ka) between 103 and 105 L mol-1 to form complexes, which changed the secondary structure of ßLG, inducing an α-helix to ß-sheet structure transition. The order of binding increased with an increasing polarity in the order of rhein > emodin > chrysophanol. In addition, the degree of radical scavenging capacity masking increased with an increasing binding affinity. Complexation with ßLG significantly increases the hydrosolubility of anthraquinones.


Assuntos
Antraquinonas/química , Lactoglobulinas/química , Polifenóis/química , Animais , Bovinos , Dicroísmo Circular , Emodina/química , Interações Hidrofóbicas e Hidrofílicas , Modelos Teóricos , Simulação de Acoplamento Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Proteínas do Soro do Leite/análise
12.
Food Chem ; 256: 427-434, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29606470

RESUMO

To help produce hypoallergenic food, this study investigated reducing the allergenicity and improving the functional properties of bovine ß-lactoglobulin (ßLG) by covalent conjugation with (-)-epigallo-catechin 3-gallate (EGCG) and chlorogenic acid (CA). The covalent bond between the polyphenols and the amino acid side-chains in ßLG was confirmed by MALDI-TOF-MS and SDS-PAGE. Structural analysis by fluorescence spectroscopy, circular dichroism (CD) and Fourier transform infrared (FTIR) indicated that the covalent conjugate of EGCG and CA led to the changed protein structure of ßLG. Western blot analysis and enzyme-linked immunosorbent assay indicated that conjugation of ßLG with these polyphenols was effective in reducing the IgE-binding capacity of ßLG. The conjugates maintained the retinol-binding activity without denaturation the protein and enhanced the thermal stability with high antioxidant activity. The study provides an innovative approach to producing hypoallergenic food.


Assuntos
Alérgenos/química , Lactoglobulinas/química , Polifenóis/química , Alérgenos/imunologia , Animais , Catequina/análogos & derivados , Catequina/química , Bovinos , Ácido Clorogênico/química , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Lactoglobulinas/imunologia , Espectrometria de Fluorescência
13.
Food Chem ; 243: 118-124, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29146317

RESUMO

Phenylpropanoid glycosides (PPGs) are important bioactive polyphenolic compounds that are widely distributed in plants. In this paper, the inhibitory effects of four selected PPGs against trypsin were investigated. The interactions between these PPGs and trypsin were further investigated by multiple spectroscopic methods and molecular docking studies. The results showed that the binding of each of these PPGs to trypsin induced changes in the natural conformation of trypsin, which inhibited the enzyme in the following order: acteoside>syringalide A 3'-α-l-rhamnopyranoside>lipedoside A-I>osmanthuside B. The binding constant (Ka) values followed the same trend. The hydrogen bond force played an important role in the interaction between each PPG and trypsin. Interestingly, the binding affinity and inhibitory effect increased as the number of phenolic hydroxyl groups increased. In addition, the effect of the phenolic hydroxyl group on the A ring had a greater effect than one on the B ring.


Assuntos
Glicosídeos/química , Glicosídeos/metabolismo , Propanóis/química , Tripsina/metabolismo , Ligação Proteica
14.
J Agric Food Chem ; 65(31): 6625-6637, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28697598

RESUMO

Downregulation of apoptotic signal pathway and activation of protective autophagy mainly contribute to the chemoresistance of tumor cells. Therefore, exploring efficient chemotherapeutic agents or isolating novel natural products that can trigger nonapoptotic and nonautophagic cell death such as lysosome-associated death is emergently required. We have recently extracted a saponin, gypenoside L (Gyp-L), from Gynostemma pentaphyllum and showed that Gyp-L was able to induce nonapoptotic cell death of esophageal cancer cells associated with lysosome swelling. However, contributions of vacuolization and lysosome to cell death remain unclear. Herein, we reveal a critical role for NADPH oxidase NOX2-mediated vacuolization and transcription factor EB (TFEB) activation in lysosome-associated cell death. We found that Gyp-L initially induced the abnormal enlarged and alkalized vacuoles, which were derived from lipid rafts dependent endocytosis. Besides, NOX2 was activated to promote vacuolization and mTORC1-independent TFEB-mediated lysosome biogenesis. Finally, raising lysosome pH could enhance Gyp-L induced cell death. These findings suggest a protective role of NOX2-TFEB-mediated lysosome biogenesis in cancer drug resistance and the tight interaction between lipid rafts and vacuolization. In addition, Gyp-L can be utilized as an alternative option to overcome drug-resistance though inducing lysosome associated cell death.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Morte Celular/efeitos dos fármacos , Gynostemma/química , Lisossomos/metabolismo , Glicoproteínas de Membrana/metabolismo , NADPH Oxidases/metabolismo , Extratos Vegetais/farmacologia , Vacúolos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Lisossomos/efeitos dos fármacos , Glicoproteínas de Membrana/genética , NADPH Oxidase 2 , NADPH Oxidases/genética , Vacúolos/efeitos dos fármacos
15.
J Med Food ; 20(6): 577-585, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28486011

RESUMO

Acteoside, the predominant polyphenol of small-leaved kudingcha, the Chinese tea, has various biological activities. In this study, we examined the acyl migration of acteoside to isoacteoside with high-temperature treatment of acteoside. The inhibitory effects of acyl-migrated acteoside and acteoside on α-amylase were investigated, as were their binding interaction with α-amylase. The binding of acteoside and isoacteoside to α-amylase was investigated by using the fluorescence spectra assay, circular dichroism, and protein-ligand docking studies. Acteoside was more effective than preheated acteoside and isoacteoside in inhibiting α-amylase activity. Acteoside and isoacteoside binding to α-amylase may induce conformational changes to α-amylase, and the binding site of acteoside and isoacteoside being near the active site pocket of α-amylase may explain the decreased activity of α-amylase. The different affinities and binding sites of acteoside and isoacteoside for α-amylase resulted in different inhibition rates, which may be due to structural differences between acteoside and isoacteoside.


Assuntos
Inibidores Enzimáticos/química , Glucosídeos/química , Ligustrum/química , Fenóis/química , alfa-Amilases/antagonistas & inibidores , Cinética , Folhas de Planta/química , Preparações de Plantas , Chá/química , alfa-Amilases/química
16.
Autophagy ; 12(9): 1593-613, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27310928

RESUMO

Modulation of autophagy has been increasingly regarded as a promising cancer therapeutic approach. In this study, we screened several ginsenosides extracted from Panax ginseng and identified ginsenoside Ro (Ro) as a novel autophagy inhibitor. Ro blocked the autophagosome-lysosome fusion process by raising lysosomal pH and attenuating lysosomal cathepsin activity, resulting in the accumulation of the autophagosome marker MAP1LC3B/LC3B and SQSTM1/p62 (sequestosome 1) in various esophageal cancer cell lines. More detailed studies demonstrated that Ro activated ESR2 (estrogen receptor 2), which led to the activation of NCF1/p47(PHOX) (neutrophil cytosolic factor 1), a subunit of NADPH oxidase, and subsequent reactive oxygen species (ROS) production. Treatment with siRNAs or inhibitors of the ESR2-NCF1-ROS axis, such as N-acetyl-L-cysteine (NAC), diphenyleneiodonium chloride (DPI), apocynin (ACN), Tiron, and Fulvestrant apparently decreased Ro-induced LC3B-II, GFP-LC3B puncta, and SQSTM1, indicating that ROS instigates autophagic flux inhibition triggered by Ro. More importantly, suppression of autophagy by Ro sensitized 5-fluorouracil (5-Fu)-induced cell death in chemoresistant esophageal cancer cells. 5-Fu induced prosurvival autophagy, and by inhibiting such autophagy, siRNAs against BECN1/beclin 1, ATG5, ATG7, and LC3B enhanced 5-Fu-induced autophagy-associated and apoptosis-independent cell death. We observed that Ro potentiates 5-Fu cytotoxicity via delaying CHEK1 (checkpoint kinase 1) degradation and downregulating DNA replication process, resulting in the delayed DNA repair and the accumulation of DNA damage. In summary, these data suggest that Ro is a novel autophagy inhibitor and could function as a potent anticancer agent in combination therapy to overcome chemoresistance.


Assuntos
Autofagossomos/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Dano ao DNA , Neoplasias Esofágicas/metabolismo , Ginsenosídeos/química , Lisossomos/metabolismo , Animais , Apoptose , Autofagia , Ciclo Celular , Sobrevivência Celular , Chlorocebus aethiops , Receptor beta de Estrogênio/metabolismo , Fluoruracila/farmacologia , Proteínas de Fluorescência Verde/metabolismo , Humanos , Camundongos , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Vero
17.
Oncotarget ; 7(30): 47387-47402, 2016 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-27329722

RESUMO

Esophageal cancer is one of the leading cause of cancer mortality in the world. Due to the increased drug and radiation tolerance, it is urgent to develop novel anticancer agent that triggers nonapoptotic cell death to compensate for apoptosis resistance. In this study, we show that treatment with gypenoside L (Gyp-L), a saponin isolated from Gynostemma pentaphyllum, induced nonapoptotic, lysosome-associated cell death in human esophageal cancer cells. Gyp-L-induced cell death was associated with lysosomal swelling and autophagic flux inhibition. Mechanistic investigations revealed that through increasing the levels of intracellular reactive oxygen species (ROS), Gyp-L triggered protein ubiquitination and endoplasm reticulum (ER) stress response, leading to Ca2+ release from ER inositol trisphosphate receptor (IP3R)-operated stores and finally cell death. Interestingly, there existed a reciprocal positive-regulatory loop between Ca2+ release and ER stress in response to Gyp-L. In addition, protein synthesis was critical for Gyp-L-mediated ER stress and cell death. Taken together, this work suggested a novel therapeutic option by Gyp-L through the induction of an unconventional ROS-ER-Ca2+-mediated cell death in human esophageal cancer.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Cálcio/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Neoplasias Esofágicas/tratamento farmacológico , Linhagem Celular Tumoral , Neoplasias Esofágicas/patologia , Gynostemma , Humanos , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Ubiquitinação
18.
Artigo em Inglês | MEDLINE | ID: mdl-26927145

RESUMO

Genetic variants at KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963 have been associated with type 2 diabetes mellitus (T2DM), but the results are contradictory in Chinese populations. The aim of the present study was to investigate the association of these four SNPs with T2DM in a large population of Han Chinese at Henan province, China. Seven-hundred-thirty-six patients with T2DM (cases) and Seven-hundred-sixty-eight healthy glucose-tolerant controls were genotyped for KCNQ1 rs151290, KLF14 rs972283, GCKR rs780094 and MTNR1B rs10830963. The association of genetic variants in these four genes with T2DM was analyzed using multivariate logistic regression. Genotypes and allele distributions of KCNQ1 rs151290 were significantly different between the cases and controls (p < 0.05). The AC and CC genotypes and the combined AC + CC genotype of rs151290 in KCNQ1 were associated with increases risk of T2DM before (OR = 1.482, 95% CI = 1.062-2.069; p = 0.021; OR = 1.544, 95% CI = 1.097-2.172, p = 0.013; and OR = 1.509, 95% CI = 1.097-2.077, p = 0.011, respectively) and after (OR = 1.539, 95% CI = 1.015-2.332, p = 0.042; OR = 1.641, 95% CI = 1.070-2.516, p = 0.023; and OR = 1.582, 95% CI = 1.061-2.358, p = 0.024; respectively) adjustment for sex, age, anthropometric measurements, biochemical indexes, smoking and alcohol consumption. Consistent with results of genotype analysis, the C allele of rs151290 in KCNQ1 was also associated with increased risk of T2DM (OR = 1.166, 95% CI = 1.004-1.355, p = 0.045). No associations between genetic variants of KLF14 rs972283, GCKR rs780094 or MTNR1B rs10830963 and T2DM were detected. The AC and CC genotypes and the C allele of rs151290 in KCNQ1 may be risk factors for T2DM in Han Chinese in Henan province.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença/epidemiologia , Polimorfismo de Nucleotídeo Único/genética , Proteínas Adaptadoras de Transdução de Sinal , Idoso , Povo Asiático/genética , China/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Variação Genética , Genótipo , Humanos , Canal de Potássio KCNQ1 , Fatores de Transcrição Kruppel-Like , Masculino , Pessoa de Meia-Idade , Receptor MT2 de Melatonina , Fatores de Transcrição Sp
19.
J Agric Food Chem ; 64(8): 1702-11, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26870999

RESUMO

Exploring novel anticancer agents that can trigger non-apoptotic or non-autophagic cell death is urgent for cancer treatment. In this study, we screened and identified an unexplored anticancer activity of gypenoside L (Gyp-L) isolated from Gynostemma pentaphyllum. We showed that treatment with Gyp-L induces non-apoptotic and non-autophagic cytoplasmic vacuolation death in human hepatocellular carcinoma (HCC) cells. Mechanically, Gyp-L initially increased the intracellular reactive oxygen species (ROS) levels, which, in turn, triggered protein ubiquitination and unfolded protein response (UPR), resulting in Ca(2+) release from endoplasm reticulum (ER) inositol trisphosphate receptor (IP3R)-operated stores and finally cytoplasmic vacuolation and cell death. Interruption of the ROS-ER-Ca(2+) signaling pathway by chemical inhibitors significantly prevented Gyp-L-induced vacuole formation and cell death. In addition, Gyp-L-induced ER stress and vacuolation death required new protein synthesis. Overall, our works provide strong evidence for the anti-HCC activity of Gyp-L and suggest a novel therapeutic option by Gyp-L through the induction of a unconventional ROS-ER-Ca(2+)-mediated cytoplasmic vacuolation death in human HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Gynostemma/química , Neoplasias Hepáticas/metabolismo , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/fisiopatologia , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/fisiopatologia , Extratos Vegetais/isolamento & purificação , Vacúolos/efeitos dos fármacos , Vacúolos/metabolismo
20.
Hum Pathol ; 46(12): 1859-71, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26433703

RESUMO

FOXG1 is a transcription factor that interacts with multiple signaling pathways and modulates neuronal differentiation in the telencephalon. Dysregulation of FOXG1 expression has been previously reported in medulloblastoma. In this study, we demonstrate a regional specific expression of FOXG1 and its colocalization with Nestin expression in the premigratory mitotically active (outer) layer of the external granular layer of the cerebellum. An inverse expression of the granular precursor cell markers, Math1 and Musashi1, in the inner nonmitotic migratory layer of the external granular layer and in the internal granular layer was observed. Furthermore, modulation of FOXG1 in the medulloblastoma cell line, DAOY, was associated with the induction of neuronal differentiation markers and significant changes in multiple signaling pathways regulating cell proliferation, differentiation, survival, and apoptosis. Additionally, we observed enhanced survival in intracerebellar mice xenografts injected with DAOY cells bearing shFOXG1 constructs versus shLuciferase construct. Overall, these findings suggest that down-modulation of FOXG1 is a prerequisite for the onset of neuronal differentiation during cerebellar development and that a decrease of FOXG1 in medulloblastoma cells offers a survival advantage in mice. We propose that the disruption of signaling pathways that promote mature neuronal differentiation by overexpressed FOXG1 is a contributing event in the neoplastic transformation of cerebellar stem cells.


Assuntos
Transformação Celular Neoplásica/metabolismo , Neoplasias Cerebelares/patologia , Fatores de Transcrição Forkhead/metabolismo , Meduloblastoma/patologia , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/patologia , Animais , Western Blotting , Diferenciação Celular/fisiologia , Transformação Celular Neoplásica/patologia , Cerebelo/embriologia , Modelos Animais de Doenças , Xenoenxertos , Humanos , Imuno-Histoquímica , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Reação em Cadeia da Polimerase , RNA Interferente Pequeno , Transdução Genética
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