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1.
Food Chem ; 399: 133991, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36037681

RESUMO

Fish oil develops particular off-odors, mainly fishy odor, from the oxidation of its characteristic fatty acids, docosahexaenoic (DHA) and eicosapentaenoic (EPA). Anchovy oil (AO) was taken as representative of fish oils. This was compared to three vegetable oils with different fatty acid compositions, i.e. camellia, sunflower and linseed oil, and differential volatile compounds were identified by static-headspace gas-chromatography ion-mobility-spectrometry (SHS-GC-IMS) and orthogonal partial-least-squares discriminant analysis (OPLS-DA) during oxidation at 60 °C. Three groups of differential volatile compounds detected at higher concentrations in the AO were screened out and two compounds, identified as 5-methylfurfural and 2-acetylfuran, were characteristic to the AO and not found in the vegetable oils. They were formed from both EPA and DHA, only present in the AO, and their formation mechanisms were proposed. The contents of 5-methylfurfural and 2-acetylfuran increased linearly with the oxidation time and consequently they could be used as oxidative markers of fish oils.


Assuntos
Quimiometria , Óleos de Peixe , Ácidos Graxos/análise , Óleos de Peixe/química , Furaldeído/análogos & derivados , Furanos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos de Plantas
2.
Food Chem ; 404(Pt B): 134724, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36332587

RESUMO

The aim of the present research was to explore the development of off-odors in fish oil from the perspective of fatty acid oxidation. It was found that the off-odors elicited by the two major ω-3 PUFAs in fish oil, i.e. DHA and EPA, were different from those by fish oil. Results showed that simultaneous oxidation of fatty acids other than DHA and EPA can be involved. The off-odors of fish oil was successfully simulated by combining oxidized samples of DHA, EPA and sunflower oil. Therefore, oxidation of oleic and linoleic acids also contributed to the off-odors in fish oil. A novel analytical approach that consisted in the combination of gas chromatography-ion mobility spectrometry (GC-IMS) and orthogonal partial least squares discriminant analysis (OPLS-DA) was applied to identify differences in the volatile components between the recombinant oil and the fish oil.


Assuntos
Ácidos Graxos Ômega-3 , Óleos de Peixe , Óleos de Peixe/química , Ácidos Graxos/análise , Ácido Eicosapentaenoico/análise , Odorantes/análise , Ácidos Docosa-Hexaenoicos/análise , Cromatografia Gasosa-Espectrometria de Massas
3.
MedComm (2020) ; 3(3): e152, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35978854

RESUMO

Lung cancer is the leading cause of cancer death worldwide, of which lung adenocarcinoma (LUAD) is the most common subtype. Metastasis is the major cause of poor prognosis and mortality for lung cancer patients, which urgently needs great efforts to be further explored. Herein, glutathione peroxidase 8 (GPX8) was identified as a novel potential pro-metastatic gene in LUAD metastatic mice models from GEO database. GPX8 was highly expressed in tumor tissues, predicting poor prognosis in LUAD patients. Knockdown of GPX8 inhibited LUAD metastasis in vitro and in vivo, while it did not obviously affect tumor growth. Knockdown of GPX8 decreased the levels of p-FAK and p-Paxillin and disturbed the distribution of focal adhesion. Furthermore, GPX8 was overexpressed in cancer-associated fibroblast (CAF) and associated with CAF infiltration in tumor microenvironment of lung cancer. GPX8 silence on fibroblasts suppressed lung cancer cell migration in the coculture system. BRD2 and RRD4 were the potential transcriptionally regulators for GPX8. Bromodomain extra-terminal inhibitor JQ1 downregulated GPX8 expression and suppressed lung cancer cell migration. Our findings indicate that highly expressed GPX8 in lung cancer cells and fibroblasts functions as a pro-metastatic factor in lung cancer. JQ1 is identified as a potential inhibitor against GPX8-mediated lung cancer metastasis.

4.
Acta Pharm Sin B ; 12(3): 1240-1253, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35530150

RESUMO

The mammalian target of rapamycin (mTOR) pathway is abnormally activated in lung cancer. However, the anti-lung cancer effect of mTOR inhibitors as monotherapy is modest. Here, we identified that ginsenoside Rh2, an active component of Panax ginseng C. A. Mey., enhanced the anti-cancer effect of the mTOR inhibitor everolimus both in vitro and in vivo. Moreover, ginsenoside Rh2 alleviated the hepatic fat accumulation caused by everolimus in xenograft nude mice models. The combination of everolimus and ginsenoside Rh2 (labeled Eve-Rh2) induced caspase-independent cell death and cytoplasmic vacuolation in lung cancer cells, indicating that Eve-Rh2 prevented tumor progression by triggering paraptosis. Eve-Rh2 up-regulated the expression of c-MYC in cancer cells as well as tumor tissues. The increased c-MYC mediated the accumulation of tribbles homolog 3 (TRIB3)/P62+ aggresomes and consequently triggered paraptosis, bypassing the classical c-MYC/MAX pathway. Our study offers a potential effective and safe strategy for the treatment of lung cancer. Moreover, we have identified a new mechanism of TRIB3/P62+ aggresomes-triggered paraptosis and revealed a unique function of c-MYC.

5.
Transl Oncol ; 14(9): 101162, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34171557

RESUMO

The anti-phagocytosis signal, CD47, prevents phagocytosis when it interacts with signal-regulatory protein alpha (SIRPα) on macrophages. Given the vital role of CD47 in immune response, further investigation on the regulation of CD47 in tumor microenvironment is needed. Herein, we identified that interferon-gamma (IFN-γ), one of the most important cytokines in the immune and inflammatory response, up-regulated CD47 expression in cancer cells and this effect could be inhibited by the JAK1/2 inhibitor ruxolitinib, as well as siRNA-mediated silencing of JAK1, STAT1, and IRF1. The IFN-γ-induced surface expression of CD47 contributed to a stronger binding affinity to SIRPα and a decrease in phagocytosis of cancer cells by macrophages. Knockdown of JAK1, STAT1, or IRF1 by siRNA reversed the decreased phagocytosis caused by IFN-γ. Besides, analysis from TCGA revealed that IFNG had a positive correlation with CD47 in various types of cancer, which was supported by the increased surface CD47 expression after IFN-γ treatment in different types of cancer cells. The discovery of IFN-γ-induced up-regulation of CD47 in cancer cells unveils another feedback inhibitory mechanism of IFN-γ, thus providing insights into cancer immunotherapy targeting CD47.

6.
Pharmacol Ther ; 219: 107694, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32980443

RESUMO

Programmed cell death-1 (PD-1)/programmed death-ligand 1 (PD-L1) blockade has been approved as the standard-of-care for the treatment of non-small cell lung cancer (NSCLC). Yet, the population of patients who benefit from the treatment remains modest, some of whom would get relapsed and progressed eventually. Combination therapy has emerged as an effective way to broaden beneficiaries from PD-1/PD-L1 immunotherapy and overcome or delay the resistance. In this review, we discuss the PD-1/PD-L1 blockade in combination with conventional chemotherapy, targeted therapy or immunotherapy. Meanwhile, we illustrate their underlying mechanisms in regulating the process of the cancer-immunity cycle, providing the rationale for the PD-1/PD-L1 blockade-based combination therapy. The challenges of combination regimens are also addressed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Imunoterapia , Neoplasias Pulmonares/tratamento farmacológico , Receptor de Morte Celular Programada 1
7.
Acta Pharmacol Sin ; 42(3): 451-459, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32678313

RESUMO

Osimertinib (AZD9291) has been widely used for the treatment of EGFR mutant non-small cell lung cancer. However, resistance to osimertinib is inevitable. In this study we elucidated the molecular mechanisms of resistance in osimertinib-resistant NCI-H1975/OSIR cells. We showed that NCI-H1975/OSIR cells underwent epithelial-mesenchymal transition (EMT), which conferred sensitivity to the GPX4 inhibitor 1S, 3R-RSL3 to induce ferroptotic cell death. The EMT occurrence resulted from osimertinib-induced upregulation of TGFß2 that activated SMAD2. On the other hand, we revealed that NCI-H1975/OSIR cells were highly dependent on NF-κB pathway for survival, since treatment with the NF-κB pathway inhibitor BAY 11-7082 or genetic silence of p65 caused much greater cell death as compared with the parental NCI-H1975 cells. In NCI-H1975 cells, osimertinib activated NF-κB pathway, evidenced by the increased p65 nuclear translocation, which was abolished by knockdown of TGFß2. In the cancer genome atlas lung adenocarcinoma data, TGFB2 transcript abundance significantly correlated with EMT-associated genes and NF-κB pathway. In addition, coexistence of EMT and activation of NF-κB pathway was observed in several NCI-H1975/OSIR clones. These findings shed new light on distinct roles of TGFß2 in osimertinib-resistant cells and provide new strategies for treatment of this resistant status.


Assuntos
Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Transição Epitelial-Mesenquimal/fisiologia , Subunidade p50 de NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/metabolismo , Antineoplásicos/farmacologia , Carbolinas/farmacologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Ferroptose/efeitos dos fármacos , Humanos , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/metabolismo
8.
Phytomedicine ; 80: 153394, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33130472

RESUMO

BACKGROUND: Programmed death-ligand 1 (PD-L1), which can be induced by interferon-gamma (IFN-γ) in the tumor microenvironment, is a critical immune checkpoint in cancer immunotherapy. Natural products which reduce IFN-γ-induced PD-L1 might be exert immunotherapy effect. Licochalcone A (LCA), a natural compound derived from the root of Glycyrrhiza inflata Batalin. (Fabaceae), was found to interfere IFN-γ-induced PD-L1. PURPOSE: The aim of this study is to further clarify the effect and the mechanism of LCA on inhibiting IFN-γ-induced PD-L1 in lung cancer cells. METHODS: The expression levels of PD-L1 were evaluated by flow cytometry, western blot and qRT-PCR. Click-iT protein synthesis assay and luciferase assay were used to identify the effect of LCA on protein synthesis. Jurkat T cell proliferation and apoptosis in the co-culture system were detected by flow cytometry. Flow cytometry was also applied to evaluate reactive oxygen species (ROS) generation. RESULTS: LCA downregulated IFN-γ-induced PD-L1 protein expression and membrane localization in human lung cancer cells, regardless of inhibiting PD-L1 mRNA level or promoting its protein degradation. LCA decreased apoptosis and proliferative inhibition of Jurkat T cells caused by IFN-γ-induced PD-L1-expressing in A549 cells in the co-culture system. Strikingly, LCA was verified as a protein synthesis inhibitor, which reduced both cap-dependent and -independent translation. LCA inhibited PD-L1 translation, likely due to inhibition of 4EBP1 phosphorylation (Ser 65) and activation of PERK-eIF2α pathway. Furthermore, LCA induced ROS generation in a time-dependent manner in lung cancer cells. N-acetyl-L-cysteine (NAC) not only revered ROS generation triggered by LCA but also restored IFN-γ-induced expression of PD-L1. Both the inhibition of 4EBP1 phosphorylation (Ser 65) and activation of PERK-eIF2α axis triggered by LCA was restored by co-treatment with NAC. CONCLUSION: LCA abrogated IFN-γ-induced PD-L1 expression via ROS generation to abolish the protein translation, indicating that LCA has the potential to be applied in cancer immunotherapy.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antígeno B7-H1/metabolismo , Chalconas/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Antígeno B7-H1/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Interferon gama/metabolismo , Interferon gama/farmacologia , Células Jurkat , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Evasão Tumoral/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
9.
Chin J Nat Med ; 18(7): 517-525, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32616192

RESUMO

Nagilactone E (NLE), a natural product with anticancer activities, is isolated from Podocarpus nagi. In this study, we reported that NLE increased programmed death ligand 1 (PD-L1) expressions at both protein and mRNA levels in human lung cancer cells, and enhanced its localization on the cell membrane. Mechanistically, NLE increased the phosphorylation and expression of c-Jun, and promoted the localization of c-Jun in the nucleus, while silencing of c-Jun by small interfering RNA (siRNA) reduced NLE-induced PD-L1. Further study showed that NLE activated the c-Jun N-terminal kinases (JNK), the upstream of c-Jun, and its inhibitor SP600125 reversed the NLE-increased PD-L1. Moreover, NLE-induced PD-L1 increased the binding intensity of PD-1 on the cell surface. In summary, NLE upregulates the expression of PD-L1 in lung cancer cells through the activation of JNK-c-Jun axis, which has the potential to combine with the PD-1/PD-L1 antibody therapies in lung cancer.


Assuntos
Antineoplásicos/farmacologia , Antígeno B7-H1/metabolismo , Diterpenos/farmacologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lactonas/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Diterpenos/química , Humanos , Lactonas/química , Estrutura Molecular
10.
J Food Sci ; 85(7): 2207-2215, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32572979

RESUMO

Trimethylamine-N-oxide (TMAO) is considered to have negative effect on human health. Different precursors of TMAO, such as choline, betaine, and L-carnitine, are commonly found in daily foods. The aim of the present study was to compare the ability of different precursors to be metabolized into TMAO, as well as the possible effect of chronic administration with TMAO precursors on TMAO production. The rate of TMAO generation after single gavage with different precursors was L-carnitine > choline >betaine. Moreover, the serum TMAO level of mice increased more than twofold after administration with choline for 3 weeks compared with L-carnitine and betaine groups, which was accompanied by the change of intestinal flora. After the gavage of choline chloride, the production for TMAO was 2.8 and 1.6 times higher in chronic choline-treated group compared with L-carnitine and betaine groups, respectively. In addition, administration with choline increased the lowest TMAO level after intraperitoneal injection of trimethylamine (TMA) hydrochloride among the three treated groups. These findings indicated that different TMAO precursors had different ability to form TMAO in vivo, and long-term dietary intervention would affect the metabolism of precursors to generate TMA and the TMA oxidation to form TMAO, suggesting that TMAO levels in vivo could be regulated by dietary intervention. PRACTICAL APPLICATION: Diverse TMAO precursors exhibited different ability to be converted into TMAO in vivo. The ability of choline to produce TMAO was stronger than that of betaine and L-carnitine. Long-term dietary intervention would affect the metabolism of precursors to generate TMA and the TMA oxidation to form TMAO, suggesting that TMAO levels in vivo could be regulated by adjustment of dietary structure.


Assuntos
Betaína/metabolismo , Carnitina/metabolismo , Colina/metabolismo , Metilaminas/sangue , Animais , Feminino , Microbioma Gastrointestinal , Intestinos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C
11.
Anticancer Agents Med Chem ; 20(8): 982-988, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32286950

RESUMO

BACKGROUND: Cassane-type diterpenoids are widely distributed in the medical plants of genus Caesalpinia. To date, plenty of cassane diterpenoids have been isolated from the genus Caesalpinia, and some of them were documented to exhibit multiple biological activities. However, the effects of these compounds on autophagy have never been reported. OBJECTIVE: To investigate the effects and mechanisms of the cassane diterpenoids including Phanginin R (PR) on autophagy in Non-Small Cell Lung Cancer (NSCLC) A549 cells. METHODS: Western blot analysis and immunofluorescence assay were performed to investigate the effects of the compounds on autophagic flux in A549 cells. The pathway inhibitor and siRNA interference were used to investigate the mechanism of PR. MTT assay was performed to detect cell viability. RESULTS: PR treatment upregulated the expression of phosphatidylethanolamine-modified microtubule-associated protein Light-Chain 3 (LC3-II) in A549 cells. Immunofluorescence assay showed that PR treatment increased the production of red-fluorescent puncta in mRFP-GFP-LC3 plasmid-transfected cells, indicating PR promoted autophagic flux in A549 cells. PR treatment activated the c-Jun N-terminal Kinase (JNK) signaling pathway while it did not affect the classical Akt/mammalian Target of Rapamycin (mTOR) pathway. Pretreatment with the JNK inhibitor SP600125 or siRNA targeting JNK or c-Jun suppressed PR-induced autophagy. In addition, cotreatment with the autophagy inhibitor Chloroquine (CQ) or inhibition of the JNK/c-Jun signaling pathway increased PR-induced cytotoxicity. CONCLUSION: PR induced cytoprotective autophagy in NSCLC A549 cells via the JNK/c-Jun signaling pathway, and autophagy inhibition could further improve the anti-cancer potential of PR.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Autofagia/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Substâncias Protetoras/farmacologia , Células A549 , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Caesalpinia/química , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Estrutura Molecular , Substâncias Protetoras/química , Substâncias Protetoras/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
12.
Biochem Pharmacol ; 175: 113921, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32201213

RESUMO

The mammalian target of rapamycin (mTOR) pathway converges diverse environmental cues to support the lung cancer growth and survival. However, the mTOR-targeted mono-therapy does not achieve expected therapeutic effect. Here, we revealed that fangchinoline (FCL), an active alkaloid that purified from the traditional Chinese medicine Stephania tetrandra S. Moore, enhanced the anti-lung cancer effect of mTOR inhibitor everolimus (EVE). The combination of EVE and FCL was effective to activate Notch 3, and subsequently evoked its downstream target c-MYC. The blockage of Notch 3 signal by the molecular inhibitor of γ-secretase or siRNA of Notch 3 reduced the c-MYC expression and attenuated the combinational efficacy of EVE and FCL on cell apoptosis and proliferation. Moreover, the c-MYC could bind to the C/EBP homologous protein (CHOP) promoter and facilitate CHOP transcription. The conditional genetic deletion of CHOP reduced the apoptosis on lung cancer cells to the same degree as blockage of Notch 3/c-MYC axis, providing further evidence for that the Notch 3/c-MYC axis regulates the transcription of CHOP and finally induces apoptosis upon co-treatment of FCL and EVE in lung cancer cells. Overall, our findings, to the best of our knowledge, firstly link CHOP to Notch 3/c-MYC axis-dependent apoptosis and provide the Notch 3/c-MYC/CHOP activation as a promising strategy for mTOR-targeted combination therapy in lung cancer treatment.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Everolimo/farmacologia , Neoplasias Pulmonares/metabolismo , Receptor Notch3/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fator de Transcrição CHOP/metabolismo , Fatores de Transcrição/metabolismo , Células A549 , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/fisiologia , Everolimo/uso terapêutico , Células HEK293 , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Serina-Treonina Quinases TOR/antagonistas & inibidores
13.
Acta Pharmacol Sin ; 41(5): 698-705, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32047261

RESUMO

Norditerpenoids and dinorditerpenoids represent diterpenoids widely distributed in the genus Podocarpus with notable chemical structures and biological activities. We previously reported that nagilactone E (NLE), a dinorditerpenoid isolated from Podocarpus nagi, possessed anticancer effects against lung cancer cells in vitro. In this study we investigated the in vivo effect of NLE against lung cancer as well as the underlying mechanisms. We administered NLE (10 mg·kg-1·d-1, ip) to CB-17/SCID mice bearing human lung cancer cell line A549 xenograft for 3 weeks. We found that NLE administration significantly suppressed the tumor growth without obvious adverse effects. Thereafter, RNA sequencing (RNA-seq) analysis was performed to study the mechanisms of NLE. The effects of NLE on A549 cells have been illustrated by GO and pathway enrichment analyses. CMap dataset analysis supported NLE to be a potential protein synthesis inhibitor. The inhibitory effect of NLE on synthesis of total de novo protein was confirmed in Click-iT assay. Using the pcDNA3-RLUC-POLIRES-FLUC luciferase assay we further demonstrated that NLE inhibited both cap-dependent and cap-independent translation. Finally, molecular docking revealed the low-energy binding conformations of NLE and its potential target RIOK2. In conclusion, NLE is a protein synthesis inhibitor with anticancer activity.


Assuntos
Fator 4 Ativador da Transcrição/antagonistas & inibidores , Antineoplásicos/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Diterpenos/farmacologia , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Inibidores da Síntese de Proteínas/farmacologia , Fator de Transcrição STAT3/antagonistas & inibidores , Células A549 , Fator 4 Ativador da Transcrição/biossíntese , Fator 4 Ativador da Transcrição/genética , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Biologia Computacional , Inibidor de Quinase Dependente de Ciclina p21/biossíntese , Inibidor de Quinase Dependente de Ciclina p21/genética , Diterpenos/administração & dosagem , Diterpenos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos SCID , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/biossíntese , Fator 2 Relacionado a NF-E2/genética , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Inibidores da Síntese de Proteínas/administração & dosagem , Inibidores da Síntese de Proteínas/isolamento & purificação , Fator de Transcrição STAT3/biossíntese , Fator de Transcrição STAT3/genética , Células Tumorais Cultivadas
14.
Angew Chem Int Ed Engl ; 59(12): 4856-4859, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-31654453

RESUMO

A large nonlinear optical (NLO) coefficient and a wide band gap are two crucial but contradictory parameters that are difficult to achieve simultaneously in a single infrared (IR) NLO compound. A salt-inclusion chalcogenide (SIC), Li[LiCs2 Cl][Ga3 S6 ] (1), was prepared that presents a nanosized tunnel framework constructed from monotype chalcogenide tetrahedra. Highly oriented covalent GaS4 tetrahedra in the host lead to a moderate second harmonic generation response (0.7 AgGaS2 ), and ionic guests effectively broaden the band gap to the widest value (4.18 eV) among all IR NLO chalcogenides, thereby achieving a remarkable balance between NLO efficiency and band gap.

15.
Antioxidants (Basel) ; 8(12)2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31817714

RESUMO

Considering the safety of synthetic antioxidants, more and more natural antioxidants have been developed and utilized in foods. This study aimed to screen out a natural antioxidant combination from many antioxidants, which could significantly affect the oxidation stability of anchovy oil, while Plackett-Burman design (PBD) methodology was employed in this screening. According to the statistical results of this design, sesamol, dihydromyricetin, teapolyphenol, and rosemary acid were four significant parameters on the oxidation stability of anchovy oil. Moreover, dihydromyricetin presented the best antioxidant effect among nine kinds of selected antioxidants when they were used alone in anchovy oil. Meanwhile, a combination including sesamol (0.02%), teapolyphenol (0.02%). and rosemary acid (0.02%) was adopted, and its antioxidant ability was similar to that of tert-butylhydroquinone (TBHQ). Additionally, phytic acid as a synergist was used and combined with sesamol, and the antioxidant ability of this combination was better than that of TBHQ. This study presented a reference for the industrial applications of natural antioxidants and synergists in anchovy oil.

16.
Food Chem Toxicol ; 131: 110537, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31150782

RESUMO

Programmed death ligand-1 (PD-L1) is an important immune checkpoint for cancer immunotherapy in clinic. In this study, we reported that platycodin D, a natural product isolated from an edible and medicinal plant Platycodon grandiflorus (Jacq.) A. DC., down-regulated the protein level of PD-L1 in lung cancer cells. Flow cytometry and immunofluorescence assay showed a weaker surface PD-L1 signal in NCI-H1975 cells after the incubation with platycodin D (10 µM) for 15 min compared to the control group. Jurkat T cells showed enhancive interleukin-2 secretion when co-cultured with platycodin D-treated NCI-H1975 cells, suggesting that platycodin D-induced PD-L1 reduction increases the activation of Jurkat T cells. An augmentation of PD-L1 protein was detected in the cell culture medium from platycodin D treatment group. Chlorpromazine (60 µM) almost abolished the platycodin D-mediated PD-L1 extracellular release and restored the membrane PD-L1. Finally, hemolysis assay exhibited that platycodin D-triggered PD-L1 extracellular release was independent of the hemolytic mechanism. Taken together, our study demonstrates that platycodin D reduces the protein level of PD-L1 in lung cancer cells via triggering its release into the cell culture medium, which sheds new light for the application of natural products in cancer immunotherapy.


Assuntos
Antígeno B7-H1/metabolismo , Saponinas/farmacologia , Triterpenos/farmacologia , Linhagem Celular Tumoral , Clorpromazina/farmacologia , Humanos , Interleucina-2/metabolismo , Células Jurkat , Transporte Proteico/efeitos dos fármacos
17.
Environ Sci Pollut Res Int ; 26(20): 20325-20343, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31093916

RESUMO

In this study, integrate electrical resistivity tomography (ERT) tests were carried out in a large-scale (5.0 × 4.0 × 7.5 m) MSW landfill cell to investigate the possibility of detecting perched leachate mounds, leachate level, and gas accumulation zones at wet landfills. The resistivity of both bulk waste and waste components at different moisture states were measured and the three-phase volumetric relationships of the waste pile were analyzed to better interpret the ERT test results in the large-scale cell. The following observations were given: (1) The relationship between resistivity and volumetric moisture content (VMC) of waste sample can be reasonably fitted by Archie's law. The resistivity of waste components at a saturated state was all lower than 21 Ω m. (2) A significant amount of void gas was entrapped in the underwater waste, being 30.4-34.8% of the whole waste pile in volume. (3) Low-resistivity zones (< 5.0 Ω m) were observed in the waste pile being fully drained under a gravity condition, which was believed to be related to a perched leachate. (4) The average VMC values of the waste layer below and above the leachate level were in the ranges of 46.5-53.1% and 28.1-41.3%, respectively. (5) Irregular variations of high-resistivity zones (> 40 Ω m) observed in the underwater waste were associated with the accumulation and dissipation of gas pressure. It was found that the "gas-breaking value" in the gas accumulation zone was up to 10.5 kPa greater than the pore liquid pressure in the stable methanogenesis stage. These findings shone a light on the possibility of using the ERT method as an efficient tool for mapping the gas/leachate distribution and improving operations at wet landfills.


Assuntos
Gases/análise , Tomografia/métodos , Instalações de Eliminação de Resíduos , Poluentes Químicos da Água/análise , Eletricidade , Eliminação de Resíduos/métodos
18.
Anticancer Agents Med Chem ; 19(6): 731-739, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30848214

RESUMO

BACKGROUND: Pemetrexed (PMT) is a multitargeted antifolate agent that is used for treating patients with Non-Small Cell Lung Cancer (NSCLC). However, patients have presented clinical responses of drug resistance to PMT. OBJECTIVE: This study aimed to explore the underlying mechanisms of PMT resistance in NSCLC cells. METHODS: PMT-resistant NCI-H460/PMT cells were established by treating with PMT in a concentrationescalation manner. MTT assay and colony formation were performed to detect cell proliferation. Immunofluorescence was used to detect the expression of Ki-67. Transwell assay was performed to measure cell migration ability. qPCR and Western blot were used to detect the mRNA and protein expression levels of indicated genes. Small interfering RNAs (siRNA) were used to knockdown ATP binding cassette subfamily B member 1 (ABCB1) and Thymidylate Synthase (TYMS). RESULTS: This study showed that compared with the parental cells, the NCI-H460/PMT cells displayed weakened proliferation and enhanced cell mobility. In addition, the NCI-H460/PMT cells demonstrated cellular senescence, which might result in PMT resistance. The NCI-H460/PMT cells exhibited cross-resistance to other chemotherapeutics, including fluorouracil, paclitaxel, doxorubicin, etoposide and gemcitabine, possibly because of the upregulated expression of ABCB1. However, the ABCB1 knockdown by siRNA failed to eradicate PMT resistance. Moreover, TYMS, a target of PMT, was obviously upregulated in the resistant cells. The genetic silence of TYMS partially abrogated PMT resistance, suggesting that the overexpression of TYMS was a key resistant mechanism of PMT. CONCLUSION: The overexpression of TYMS was an important resistance mechanism of PMT for KRAS-mutated NCI-H460 cells. Cross-resistance to other chemotherapeutics should be considered in addressing PMT resistance.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Pemetrexede/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Proteínas Proto-Oncogênicas p21(ras)/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
19.
Phytomedicine ; 52: 32-39, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30599910

RESUMO

BACKGROUND: Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-related death around the world. Epithelial-mesenchymal transition (EMT) has been documented to increase motility and invasiveness of cancer cells, which promotes cancer metastasis. PURPOSE: This study aims to investigate the inhibitory effects and mechanisms of the dinorditerpenoids and norditerpenoids isolated from the seeds of Podocarpus nagi against transforming growth factor (TGF)-ß1-induced EMT. METHODS: A series of dinorditerpenoids and norditerpenoids were isolated from the seeds of P. nagi. Western blot and quantitative real-time PCR assays were performed to determine the expression levels of relative proteins and mRNA, along with immunofluorescence, Smad-binding element (SBE)-luciferase and chromatin immunoprecipitation (ChIP) assays for the mechanism study. Transwell assays were conducted to determine the effect of the compounds on cell migration and invasion. RESULTS: Nagilactone E (NLE) showed the superior inhibitory effect against TGF-ß1-induced EMT. NLE treatment dramatically inhibited TGF-ß1-induced expression of EMT markers in A549 cells. Mechanism study indicated that NLE markedly suppressed TGF-ß1-induced Smad2 and Smad3 activation and nuclear translocation. SBE-luciferase and ChIP assays showed that NLE inhibited the combining of Smad3 to SBE in the promoters of the cell signaling factors. NLE co-treatment attenuated TGF-ß1-induced up-regulation of the protein and mRNA levels of TGF-ß receptor TßRI. Furthermore, NLE inhibited TGF-ß1-stimulated cell migration and invasion, as well as up-regulation of the key signaling proteins related with migration and invasion. CONCLUSION: NLE inhibited TGF-ß/Smad signaling pathway, thereafter suppressed TGF-ß1-induced EMT, migration and invasion in NSCLC A549 cells.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Diterpenos/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Fator de Crescimento Transformador beta1/farmacologia , Células A549 , Movimento Celular/efeitos dos fármacos , Gleiquênias/química , Humanos , Invasividade Neoplásica , Sementes/química , Transdução de Sinais/efeitos dos fármacos , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo
20.
Mol Med Rep ; 18(1): 610-616, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29749525

RESUMO

With extensive pharmacological actions, quercetin has anti­oxidant, free radical scavenging, anti­tumor, anti­inflammatory, anti­bacterial and anti­viral activity. Quercetin also reduces blood glucose and reduces high blood pressure, and has immunoregulation and cardiovascular protection functions. Additionally, it has been reported that it can reduce depression. The current study evaluated whether quercetin protects against inflammation, matrix metalloproteinase­2 (MMP­2) activation and apoptosis induction in a rat model of cardiopulmonary resuscitation (CPR), and whether Bmi­1 expression was involved in the effects. In CPR model rats, treatment with quercetin significantly recovered left ventricular ejection fraction, left ventricular fractional shortening, ejection fraction (%), and left ventricle weight/body weight. Treatment with quercetin significantly inhibited ROS generation, inflammation and MMP­2 protein expression in the rat model CPR. Finally, quercetin significantly suppressed caspase­3 activity and activated Bmi­1 protein expression in the rat model of CPR. The results demonstrated that quercetin protects against inflammation, MMP­2 activation and apoptosis induction in a rat model of CPR, and that this may be mediated by modulating Bmi­1 expression.


Assuntos
Reanimação Cardiopulmonar , Inflamação , Metaloproteinase 2 da Matriz/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Quercetina/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Animais , Apoptose , Modelos Animais , Substâncias Protetoras/farmacologia , Ratos
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