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1.
PLoS One ; 15(8): e0229477, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32822343

RESUMO

The research was conducted in the "logical series" of seven ligands: chromone, flavone, 3-hydroxyflavone, 3,7-dihydroxyflavone, galangin, kaempferol and quercetin. Each subsequent ligand differs from the previous one, among others by an additional hydroxyl group. The studied chromone derivatives are plant secondary metabolites which play an important role in growth, reproduction, and resistance to pathogens. They are important food ingredients with valuable pro-health properties. The studies of the relationships between their molecular structure and biological activity facilitate searching for new chemical compounds with important biological properties not by trial and error, but concerning the impact of specific changes in their structure on the compound properties. Therefore several pectroscopic methods (FT-IR, FT-Raman, 1H and 13C NMR) were applied to study the molecular structure of the compounds in the series. Moreover the quantum-chemical calculations at B3LYP/6-311++G** were performed to obtained the theoretical NMR spectra, NBO atomic charge, global reactivity descriptors and thermodynamic parameters. The antioxidant activity of the compounds was tested in the DPPH and FRAP assays and the mechanism of antioxidant activity was discussed based on the results on theoretical calculations. The cytotoxicity of the ligands toward human epithelial colorectal adenocarcinoma Caco2 cells was estimated and correlated with the lipophilicity of the compounds. The principal component analyses (PCA) and hierarchical cluster analysis were used to study the dependency between the molecular structure of ligands and their biological activity. The experimental data were related to the theoretical ones. The found regular changes in physicochemical properties correlated well with the systematic changes in antioxidant and biological properties.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cromonas/química , Cromonas/farmacologia , Dieta , Células CACO-2 , Teoria da Densidade Funcional , Humanos , Interações Hidrofóbicas e Hidrofílicas , Relação Estrutura-Atividade
2.
Life Sci ; 252: 117666, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32298737

RESUMO

AIMS: Euscaphic acid and Tormentic acid are aglycones of Kaji-ichigoside F1 and Rosamultin, respectively. These four compounds are pentacyclic triterpenoid, isolated from the subterranean root of the Potentilla anserina L. Based on the protective roles against hypoxia-induced apoptosis of Euscaphic acid and Tormentic acid in vascular endothelial cells, this study was designed to determine the mechanisms. MAIN METHODS: The model of hypoxic injuries in EA. hy926 cells was established. Through applications of PI3K/AKT inhibitor, LY294002 and ERK1/2 inhibitor, PD98059, we explored the relationships between pharmacodynamic mechanisms and PI3K/AKT or ERK 1/2 signaling pathway. The anti-hypoxic effects were studied by methyl-thiazolyl-tetrazolium (MTT) assay, Hematoxylin-Eosin (HE) staining, DAPI staining, and flow cytometry. The mechanisms of anti-mitochondrial apoptosis were explored by western blot. The expressions of p-ERK 1/2, ERK 1/2, p-AKT, AKT, p-NF-κB, NF-κB, Bcl-2, Bax, Cyt C, cleaved caspase-9 and cleaved caspase-3 were detected. KEY FINDINGS: Euscaphic acid protected vascular endothelial cells against hypoxia-induced apoptosis via ERK1/2 signaling pathway, and Tormentic acid brought its efficacy into full play via PI3K/AKT and ERK1/2 signaling pathways. In addition, PI3K/AKT signaling pathway positively regulated ERK1/2 pathway, and ERK1/2 pathway negatively regulated PI3K/AKT pathway. SIGNIFICANCE: This evidence provides theoretical and experimental basis for the following research on anti-hypoxic drugs of Potentilla anserina L.


Assuntos
Apoptose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Triterpenos/farmacologia , Hipóxia Celular/efeitos dos fármacos , Linhagem Celular , Cromonas/farmacologia , Células Endoteliais/metabolismo , Flavonoides/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinase/metabolismo , Potentilla/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos
3.
World Neurosurg ; 138: e659-e664, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32179193

RESUMO

OBJECTIVE: To investigate mechanism of endoplasmic reticulum (ER) stress-mediated autophagy in spinal cord injury (SCI). METHODS: An in vitro model of spinal cord injury (SCI) was established by recombinant human beta nerve growth factor (NGF)-induced PC12 cells. Immunofluorescence was used to detect properties of PC12 cells induced by NGF. Western blot assay was used to detect expressions of the autophagy-related protein microtubule-associated protein 1 light chain 3 (LC3)I/II, the ER stress-related protein (HSPA5/GRP78), as well as the PI3K/AKT/mTOR signaling pathway-related proteins after mechanical injury at different time points. Then the sample assigned into sham, SCI, LY294002, SCI+LY294002, 4-PBA (4-phenylbutyric acid), and SCI+4-PBA groups. The expressions of the LC3I/II and PI3K/AKT/mTOR signaling pathway-related proteins were detected by Western blot assay. RESULTS: NGF-induced PC12 cells have neurophysiological characteristics. After administration of the PI3K-specific inhibitor LY294002, phosphorylation levels of AKT and mTOR decreased, and the ratio of LC3II/I was higher in the inhibitor-treated injury group than the simple-injury group. After administration of the ER stress inhibitor 4-PBA, the results were similar to LY294002 group's results compared with SCI group. CONCLUSIONS: Our study showed that NGF-induced PC12 cells can induce autophagy and ER stress after mechanical injury. ER stress inhibitor 4-PBA obtained similar effects to PI3K inhibitor LY294002, enhanced autophagy via PI3K/AKT/mTOR signaling pathway.


Assuntos
Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator de Crescimento Neural/farmacologia , Células PC12 , Fenilbutiratos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Cromonas/farmacologia , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Morfolinas/farmacologia , Proteína Oncogênica v-akt/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosforilação , Ratos , Proteínas Recombinantes/farmacologia , Traumatismos da Medula Espinal/tratamento farmacológico , Serina-Treonina Quinases TOR/efeitos dos fármacos
4.
Proc Natl Acad Sci U S A ; 117(14): 8013-8021, 2020 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-32193335

RESUMO

AMP-activated protein kinase (AMPK) functions as an energy sensor and is pivotal in maintaining cellular metabolic homeostasis. Numerous studies have shown that down-regulation of AMPK kinase activity or protein stability not only lead to abnormality of metabolism but also contribute to tumor development. However, whether transcription regulation of AMPK plays a critical role in cancer metastasis remains unknown. In this study, we demonstrate that AMPKα1 expression is down-regulated in advanced human breast cancer and is associated with poor clinical outcomes. Transcription of AMPKα1 is inhibited on activation of PI3K and HER2 through ΔNp63α. Ablation of AMPKα1 expression or inhibition of AMPK kinase activity leads to disruption of E-cadherin-mediated cell-cell adhesion in vitro and increased tumor metastasis in vivo. Furthermore, restoration of AMPKα1 expression significantly rescues PI3K/HER2-induced disruption of cell-cell adhesion, cell invasion, and cancer metastasis. Together, these results demonstrate that the transcription control is another layer of AMPK regulation and suggest a critical role for AMPK in regulating cell-cell adhesion and cancer metastasis.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Animais , Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Linhagem Celular Tumoral , Cromonas/farmacologia , Intervalo Livre de Doença , Regulação para Baixo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Lapatinib/farmacologia , Camundongos , Morfolinas/farmacologia , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Prognóstico , Receptor ErbB-2/antagonistas & inibidores , Receptor ErbB-2/metabolismo , Análise Serial de Tecidos , Transcrição Genética/efeitos dos fármacos , Ativação Transcricional , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Horm Cancer ; 11(2): 87-96, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32037484

RESUMO

Proline-, glutamic acid-, leucine-rich protein 1 (PELP1) is a novel estrogen receptor (ER) coregulator, demonstrated distinctive characters from other ERα coregulators, and has been suggested to be involved in metastasis of several cancers. In ERα-positive breast cancer, PELP1 overexpression enhanced ruffles and filopodium-like structure stimulated by estradiol (E2) through extranuclear cell signaling transduction hereby increased cell motility. However, whether PELP1 is also involved in extracellular matrix remodeling of ERα-positive breast cancer cells is still unknown. In this study, we investigated the role of PELP1 in E2-induced MMP-9 expression and the underlined mechanism. The results demonstrated the following: E2-induced ERα-positive MCF-7 breast cancer cell MMP-9 mRNA and protein expression in a rapid response and concentration-dependent manner. Knocked down PELP1 significantly suppressed E2-induced MMP-9 expression. E2-bovine serum albumin (BSA), a large molecular membrane-impenetrable conjugate of E2, can also upregulate MMP-9 protein expression in MCF-7, and the action of E2-BSA can be abolished by PI3K inhibitor LY294002; treating MCF-7 simultaneously with PELP1-shRNA and LY294002 did not show synergetic inhibitory effect on E2-BSA-induced MMP-9 expression. Our results indicated that estrogen-induced MMP-9 expression in ER-positive breast cancer cells may be through PELP1-mediated PI3K/Akt signaling pathway.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas Correpressoras/metabolismo , Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Metaloproteinase 9 da Matriz/biossíntese , Fatores de Transcrição/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Cromonas/farmacologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Células MCF-7 , Metaloproteinase 9 da Matriz/genética , Morfolinas/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais
6.
Oxid Med Cell Longev ; 2020: 5967434, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32082480

RESUMO

Oxidative stress-mediated endothelial injury is considered to be involved in the pathogenesis of various cardiovascular diseases. Farrerol, a typical natural flavanone from the medicinal plant Rhododendron dauricum L., has been reported to show protective effects against oxidative stress-induced endothelial injuries in our previous study. However, its action molecular mechanisms and targets are still unclear. In the present study, we determined whether farrerol can interact with glycogen synthase kinase 3ß- (GSK-3ß-) nuclear factor erythroid 2-related factor 2- (Nrf2-) antioxidant response element (ARE) signaling, which is critical in defense against oxidative stress. Our results demonstrated that farrerol could specifically target Nrf2 negative regulator GSK-3ß and inhibit its kinase activity. Mechanistic studies proved that farrerol could induce an inhibitory phosphorylation of GSK-3ß at Ser9 without affecting the expression level of total GSK-3ß protein and promote the nuclear translocation of Nrf2 as well as the mRNA and protein expression of its downstream target genes heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1) in EA.hy926 cells. Further studies performed with GSK-3ß siRNA and specific inhibitor lithium chloride (LiCl) confirmed that GSK-3ß inhibition was involved in farrerol-mediated endothelial protection and Nrf2 signaling activation. Moreover, molecular docking and molecular dynamics studies revealed that farrerol could bind to the ATP pocket of GSK-3ß, which is consistent with the ATP-competitive kinetic behavior. Collectively, our results firstly demonstrate that farrerol could attenuate endothelial oxidative stress by specifically targeting GSK-3ß and further activating the Nrf2-ARE signaling pathway.


Assuntos
Elementos de Resposta Antioxidante/genética , Cromonas/farmacologia , Células Endoteliais/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Fator de Transcrição NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/farmacologia , Linhagem Celular , Núcleo Celular/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Cromonas/química , Células Endoteliais/enzimologia , Células Endoteliais/metabolismo , Endotélio/efeitos dos fármacos , Endotélio/enzimologia , Endotélio/metabolismo , Glicogênio Sintase Quinase 3 beta/química , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Heme Oxigenase-1/metabolismo , Humanos , Cinética , Cloreto de Lítio/farmacologia , Simulação de Acoplamento Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator de Transcrição NF-E2/genética , Estresse Oxidativo/genética , Fosforilação , RNA Interferente Pequeno , Transdução de Sinais/genética
7.
Life Sci ; 246: 117428, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32057901

RESUMO

PURPOSE: Arl4c is overexpressed in several cancer tissues and is involved in cancer development. Nevertheless, the exact mechanism that regulates Arl4c expression in lung cancer has not been fully elucidated. The aim of this study was to investigate the regulatory mechanism of Arl4c and to explore potential chemotherapeutic drugs targeting Arl4c. METHODS: Immunohistochemistry was used to examine Arl4c expression levels in human lung adenocarcinoma cancer specimens. Protein expression was detected by western blot. Overexpression of Arl4c-Flag protein was used to detect the ubiquitination of Arl4c. A short interfering RNA against Arl4c was used for gene silencing. RESULTS: Arl4c was overexpressed in lung cancer tissues, and knockdown of Arl4c expression by siRNA decreased lung cancer A549 and 95-D cell proliferation. In addition, Arl4c expression was downregulated via inhibition of the AKT pathway in A549 and 95-D cells, whereas exposure to benzo (a) pyrene (a carcinogen in smoke) increased Arl4c expression in 16HBE cells via AKT activation. Finally, we found that chemotherapy drug hydroxycamptothecin (HCPT) could decrease Arl4c expression levels by inhibiting the activation of the AKT pathway in A549 and 95-D cells. Moreover, accumulation of ubiquitinated Arl4c protein was increased by HCPT and LY294002 (an AKT inhibitor) treatment whereas the proteasome inhibitor MG-132 attenuated the inhibitory effect of HCPT and LY294002 on Arl4c expression. CONCLUSION: Here, we highlighted the AKT pathway as an important regulatory pathway for Arl4c expression in lung cancer cells and identified HCPT as a promising drug for lung adenocarcinoma treatment that functioned by targeting Arl4c expression.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Células A549 , Western Blotting , Camptotecina/análogos & derivados , Camptotecina/farmacologia , Linhagem Celular Tumoral , Cromonas/farmacologia , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Leupeptinas/farmacologia , Morfolinas/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Fumar/efeitos adversos
8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 110-118, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027262

RESUMO

OBJECTIVE: To investigate the proliferation inhibition and pro-apoptosis effect of LY294002 (PI3K/AKT inhibtor) combined with daunorubicin (DNR) on the chronic myeloid leurenia cell line K562 and its possible mechanisms. METHODS: The effect of LY294002 and DNR on the proliferation of K562 cells in different treating time and concentration were measured by MTT assay. The cell cycle was determined by flow cytometry, the mRNA and protein expression of SKP2 , P27, BCL-2 and BAX were determined by RT-PCR and Western blot. RESULTS: LY294002 and DNR were able to inhibit the growth of K562 cells and promote apoptosis in time- and concentration-dependent manner (P<0.05), both the cell proliferation-inhibiting rate and apoptosis rate in combination therapy group were higher than that in DNR-monotherapy group (P<0.05). After K562 cells treated by LY294002 combined DNR for 36 h, the cells were statistically significantly reduced in G2/M phase (P<0.05), as compared with control group and DNR group. Compared with DNR group, the cell level of G0/G1 phase rased (P<0.05) and cell level of S phase decreased (P>0.05). Compared with DNR group, the expresson of SKP2 and BCL-2 mRNA decreased, and the expression of P27 mRNA increased in the combination therapy group (P<0.05). The expression of BAX mRNA was not significantly different between different groups. The same result was found in the protein expression. CONCLUSION: LY294002 has the sensibilizative effect on DNR chemotherapy, which may be relative with blocking the cell cycle and inducing cell apoptosis.


Assuntos
Cromonas/farmacologia , Morfolinas/farmacologia , Apoptose , Daunorrubicina , Humanos , Células K562 , Fosfatidilinositol 3-Quinases
9.
J Agric Food Chem ; 68(7): 2024-2030, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32037814

RESUMO

Artocarpus heterophyllus (jack tree) is an evergreen fruit tree belonging to the genus Artocarpus (Moraceae), which is widely distributed in subtropical and tropical regions of Asia. Its fruits (jackfruit), well-known as the world's largest tree-borne fruit, are being consumed in our daily diets as a very popular tropical fruit throughout the world and have been confirmed to hold various health benefits. In this study, five new prenylated chromones, artocarheterones A-E (1-5), as well as seven known prenylated chromones (6-12) were purified and isolated from the ripe fruits of A. heterophyllus (jackfruit). Their chemical structures were determined through comprehensive spectroscopic methods. This is the first report on prenylated chromones isolated from A. heterophyllus. The anti-HIV-1 effects of all isolated chromones were assessed in vitro. As a result, prenylated chromones (1-12) showed remarkable anti-HIV-1 effects with EC50 values ranging from 0.09 to 9.72 µM. These research results indicate that the isolation and characterization of these prenylated chromones with remarkable anti-HIV-1 activities from the ripe fruits of A. heterophyllus could be significant to the discovery and development of new anti-HIV-1 drugs.


Assuntos
Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Artocarpus/química , Cromonas/química , Cromonas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Frutas/química , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Estrutura Molecular , Prenilação
10.
Anticancer Res ; 40(1): 87-95, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31892556

RESUMO

BACKGROUND/AIM: Very few studies are available about the biological activity of 3-styrylchromones. Our previous study demonstrated the importance of methoxy group at 6-position of the chromone ring and hydroxyl group at 4'-position of phenyl group in styryl moiety. As a sequel of this study, we synthesized fourteen compounds that include eight 3-styrylchromones where methoxy group was introduced at 7-position of chromone rings, and then evaluated their tumor-specificity. MATERIALS AND METHODS: Tumor-specificity (TS) was calculated by relative cytotoxicity against human oral squamous cell carcinoma cell lines versus human normal oral cells. Apoptosis induction and growth arrest were monitored by cell-cycle analysis. Quantitative structure-activity relationship analysis of TS was performed with 3,167 chemical descriptors. RESULTS AND DISCUSSION: Two compounds, 7-methoxy-3-[(1E)-2-phenylethenyl]-4H-1-benzopyran-4-one [7] and 3-[(1E)-2-(4-hydroxyphenyl)ethenyl]-7-methoxy-4H-1-benzopyran-4-one [14] showed higher tumor-specificity than doxorubicin and 5-FU, suggesting the importance of methoxy group in 7-position of the chromone ring. These compounds induced the apoptosis and mitotic arrest in HSC-2 cells. The tumor-specificity of 3-styrylchromone derivatives were most correlated with descriptors for molecule shape and electronic charge. The present study suggested that modification by introducing methoxy group at 7-position, instead at 6-position, further increased the tumor-specificity of 3-styrylchromone.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Cromonas/química , Cromonas/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Relação Quantitativa Estrutura-Atividade
11.
Acta Biochim Biophys Sin (Shanghai) ; 52(1): 64-71, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31889183

RESUMO

Previous studies have shown that during severe acute pancreatitis (SAP) attacks, hydrogen sulfide (H2S) is released in the colon. However, the roles played by H2S in regulating enteric nerves remain unclear. In this study, we examined the association between SAP-induced H2S release and loss of intestinal motility, and also explored the relevant mechanism in enteric nerve cells. A rat SAP model was constructed and enteric nerve cells were prepared. Intestinal mobility was evaluated by measuring the number of bowel movements at indicated time points and by performing intestinal propulsion tests. The production of inflammatory cytokines during a SAP attack was quantified by ELISA, and the levels of cystathionine-γ-lyase (CSE) and cystathionine-ß-synthase (CBS) were examined by immunohistochemistry and western blot analysis. In vivo studies showed that PI3K/Akt/Sp1 signaling in enteric nerve cells was blocked, confirming the mechanism of endogenous H2S formation by western blot analysis and immunofluorescence. Our results also showed that rats with SAP symptoms had reduced intestinal motility. Furthermore, PI3K/Akt/Sp1 signaling was triggered and CSE expression was up-regulated, and these changes were associated with H2S formation in the colon. In addition, propargylglycine reduced the levels of inflammatory cytokines and suppressed the release of H2S. Enteric nerve cells that were incubated with LY294002 and transfected with a Sp1-knockdown vector displayed decreased levels of CSE production, which led to a decrease in H2S production. These results suggest that SAP symptoms suppressed the intestinal motility of rats via the release of H2S in enteric nerve cells, which was dependent on the inflammation-induced PI3K/Akt/Sp1 signaling pathway.


Assuntos
Movimento Celular , Sistema Nervoso Entérico/patologia , Sulfeto de Hidrogênio/metabolismo , Neurônios/metabolismo , Pancreatite/metabolismo , Animais , Cromonas/farmacologia , Cistationina beta-Sintase/metabolismo , Cistationina gama-Liase/metabolismo , Citocinas/metabolismo , Motilidade Gastrointestinal , Técnicas de Silenciamento de Genes , Inflamação/metabolismo , Masculino , Morfolinas/farmacologia , Pancreatite/induzido quimicamente , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Ácido Taurocólico/efeitos adversos , Ácido Taurocólico/farmacologia , Transfecção
12.
Oxid Med Cell Longev ; 2020: 9741369, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31998447

RESUMO

Spinal cord injury (SCI) is a devastating disease that may lead to lifelong disability. Thus, seeking for valid drugs that are beneficial to promoting axonal regrowth and elongation after SCI has gained wide attention. Metformin, a glucose-lowering agent, has been demonstrated to play roles in various central nervous system (CNS) disorders. However, the potential protective effect of metformin on nerve regeneration after SCI is still unclear. In this study, we found that the administration of metformin improved functional recovery after SCI through reducing neuronal cell apoptosis and repairing neurites by stabilizing microtubules via PI3K/Akt signaling pathway. Inhibiting the PI3K/Akt pathway with LY294002 partly reversed the therapeutic effects of metformin on SCI in vitro and vivo. Furthermore, metformin treatment weakened the excessive activation of oxidative stress and improved the mitochondrial function by activating the nuclear factor erythroid-related factor 2 (Nrf2) transcription and binding to the antioxidant response element (ARE). Moreover, treatment with Nrf2 inhibitor ML385 partially abolished its antioxidant effect. We also found that the Nrf2 transcription was partially reduced by LY294002 in vitro. Taken together, these results revealed that the role of metformin in nerve regeneration after SCI was probably related to stabilization of microtubules and inhibition of the excessive activation of Akt-mediated Nrf2/ARE pathway-regulated oxidative stress and mitochondrial dysfunction. Overall, our present study suggests that metformin administration may provide a potential therapy for SCI.


Assuntos
Axônios/fisiologia , Metformina/farmacologia , Microtúbulos , Estresse Oxidativo/efeitos dos fármacos , Regeneração/efeitos dos fármacos , Traumatismos da Medula Espinal , Animais , Cromonas/farmacologia , Microtúbulos/metabolismo , Microtúbulos/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Morfolinas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Elementos de Resposta , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologia
13.
Sci Rep ; 10(1): 1326, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992748

RESUMO

Overcoming the global health threat of HIV infection requires continuous pipelines of novel drug candidates. We identified the γ-pyrone polyketides Aureothin/Neoaureothin as potent hits by anti-HIV screening of an extensive natural compound collection. Total synthesis of a structurally diverse group of Aureothin-derivatives successfully identified a lead compound (#7) superior to Aureothin that combines strong anti-HIV activity (IC90<45 nM), photostability and improved cell safety. Compound #7 inhibited de novo virus production from integrated proviruses by blocking the accumulation of HIV RNAs that encode the structural components of virions and include viral genomic RNAs. Thus, the mode-of-action displayed by compound #7 is different from those of all current clinical drugs. Proteomic analysis indicated that compound #7 does not affect global protein expression in primary blood cells and may modulate cellular pathways linked to HIV infection. Compound #7 inhibited multiple HIV genotypes, including HIV-type 1 and 2 and synergistically inhibited HIV in combination with clinical reverse transcriptase and integrase inhibitors. We conclude that compound #7 represents a promising new class of HIV inhibitors that will facilitate the identification of new virus-host interactions exploitable for antiviral attack and holds promise for further drug development.


Assuntos
Antivirais/farmacologia , Infecções por HIV/virologia , HIV/efeitos dos fármacos , HIV/fisiologia , Policetídeos/farmacologia , Replicação Viral/efeitos dos fármacos , Antivirais/síntese química , Antivirais/química , Cromonas/farmacologia , Desenho de Fármacos , Sinergismo Farmacológico , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Policetídeos/síntese química , Policetídeos/química , Cultura Primária de Células
14.
PLoS One ; 15(1): e0227340, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31910234

RESUMO

The PI3K/Akt pathway is interconnected to protein kinase CK2, which directly phosphorylates Akt1 at S129. We have previously found that, in HK-2 renal cells, downregulation of the CK2 regulatory subunit ß (shCK2ß cells) reduces S129 Akt phosphorylation. Here, we investigated in more details how the different CK2 isoforms impact on Akt and other signaling pathways. We found that all CK2 isoforms phosphorylate S129 in vitro, independently of CK2ß. However, in HK-2 cells the dependence on CK2ß was confirmed by rescue experiments (CK2ß re-expression in shCK2ß HK-2 cells), suggesting the presence of additional components that drive Akt recognition by CK2 in cells. We also found that CK2ß downregulation altered the phosphorylation ratio between the two canonical Akt activation sites (pT308 strongly reduced, pS473 slightly increased) in HK-2 cells. Similar results were found in other cell lines where CK2ß was stably knocked out by CRISPR-Cas9 technology. The phosphorylation of rpS6 S235/S236, a downstream effector of Akt, was strongly reduced in shCK2ß HK-2 cells, while the phosphorylation of two Akt direct targets, PRAS40 T246 and GSK3ß S9, was increased. Differently to what observed in response to CK2ß down-regulation, the chemical inhibition of CK2 activity by cell treatment with the specific inhibitor CX-4945 reduced both the Akt canonical sites, pT308 and pS473. In CX-4945-treated cells, the changes in rpS6 pS235/S236 and GSK3ß pS9 mirrored those induced by CK2ß knock-down (reduction and slight increase, respectively); on the contrary, the effect on PRAS40 pT246 phosphorylation was sharply different, being strongly reduced by CK2 inhibition; this suggests that this Akt target might be dependent on Akt pS473 status in HK-2 cells. Since PI3K/Akt and ERK1/2/p90rsk pathways are known to be interconnected and both modulated by CK2, with GSK3ß pS9 representing a convergent point, we investigated if ERK1/2/p90rsk signaling was affected by CK2ß knock-down and CX-4945 treatment in HK-2 cells. We found that p90rsk was insensitive to any kind of CK2 targeting; therefore, the observation that, similarly, GSK3ß pS9 was not reduced by CK2 blockade suggests that GSK3ß phosphorylation is mainly under the control of p90rsk in these cells. However, we found that the PI3K inhibitor LY294002 reduced GSK3ß pS9, and concomitantly decreased Snail1 levels (a GSK3ß target and Epithelial-to-Mesenchymal transition marker). The effects of LY294002 were observed also in CK2ß-downregulated cells, suggesting that reducing GSK3ß pS9 could be a strategy to control Snail1 levels in any situation where CK2ß is defective, as possibly occurring in cancer cells.


Assuntos
Caseína Quinase II/genética , Glicogênio Sintase Quinase 3 beta/genética , Proteína Oncogênica v-akt/genética , Fatores de Transcrição da Família Snail/genética , Sistemas CRISPR-Cas/genética , Linhagem Celular , Cromonas/farmacologia , Transição Epitelial-Mesenquimal/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Morfolinas/farmacologia , Naftiridinas/farmacologia , Fosfatidilinositol 3-Quinases/genética , Fosforilação/efeitos dos fármacos , Isoformas de Proteínas , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Transdução de Sinais/efeitos dos fármacos
15.
Chem Biodivers ; 17(1): e1900547, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31916685

RESUMO

Four previously unreported chromones, 5-hydroxy-2-(hydroxymethyl)-8-methoxy-4H-chromen-4-one (1), (5R,7S)-5,7-dihydroxy-2-propyl-5,6,7,8-tetrahydro-4H-chromen-4-one (2), (5R,7S)-5,7-dihydroxy-2-methyl-5,6,7,8-tetrahydro-4H-chromen-4-one (3), and (5R,7S)-5,7-dihydroxy-2-[(E)-prop-1-en-1-yl]-5,6,7,8-tetrahydro-4H-chromen-4-one (4), as well as one known analogue 5-hydroxy-2-methyl-4H-chromen-4-one (5) were isolated from the fermentation broth of the endophytic fungus Colletotrichum gloeosporioides derived from the mangrove Ceriops tagal. Their structures were elucidated based on extensive spectroscopic analyses. The absolute configurations of 2-4 were determined by comparison the experimental and calculated electronic circular dichroism (ECD) spectra. Compound 2 showed cytotoxic activity against A549 cell line with the IC50 value of 0.094 mm.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Cromonas/isolamento & purificação , Cromonas/farmacologia , Colletotrichum/química , Células A549 , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Cromonas/química , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
16.
Cancer Res ; 80(4): 843-856, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31911549

RESUMO

Among malignant mesotheliomas (MM), the sarcomatoid subtype is associated with higher chemoresistance and worst survival. Due to its low incidence, there has been little progress in the knowledge of the molecular mechanisms associated with sarcomatoid MM, which might help to define novel therapeutic targets. In this work, we show that loss of PTEN expression is frequent in human sarcomatoid MM and PTEN expression levels are lower in sarcomatoid MM than in the biphasic and epithelioid subtypes. Combined Pten and Trp53 deletion in mouse mesothelium led to nonepithelioid MM development. In Pten;Trp53-null mice developing MM, the Gαi2-coupled receptor subunit activated MEK/ERK and PI3K, resulting in aggressive, immune-suppressed tumors. Combined inhibition of MEK and p110ß/PI3K reduced mouse tumor cell growth in vitro. Therapeutic inhibition of MEK and p110ß/PI3K using selumetinib (AZD6244, ARRY-142886) and AZD8186, two drugs that are currently in clinical trials, increased the survival of Pten;Trp53-null mice without major toxicity. This drug combination effectively reduced the proliferation of primary cultures of human pleural (Pl) MM, implicating nonepithelioid histology and high vimentin, AKT1/2, and Gαi2 expression levels as predictive markers of response to combined MEK and p110ß/PI3K inhibition. Our findings provide a rationale for the use of selumetinib and AZD8186 in patients with MM with sarcomatoid features. This constitutes a novel targeted therapy for a poor prognosis and frequently chemoresistant group of patients with MM, for whom therapeutic options are currently lacking. SIGNIFICANCE: Mesothelioma is highly aggressive; its sarcomatoid variants have worse prognosis. Building on a genetic mouse model, a novel combination therapy is uncovered that is relevant to human tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Mesotelioma/tratamento farmacológico , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Pleurais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Cromonas/farmacologia , Cromonas/uso terapêutico , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Modelos Animais de Doenças , Epitélio/patologia , Feminino , Técnicas de Introdução de Genes , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mesotelioma/genética , Mesotelioma/patologia , Camundongos , Camundongos Knockout , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Terapia de Alvo Molecular/métodos , PTEN Fosfo-Hidrolase/genética , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Peritônio/patologia , Pleura/patologia , Neoplasias Pleurais/genética , Neoplasias Pleurais/patologia , Cultura Primária de Células , Prognóstico , Inibidores de Proteínas Quinases/uso terapêutico , Proteína Supressora de Tumor p53/genética
17.
Chem Biol Interact ; 317: 108946, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31935362

RESUMO

Trigonelline is a plant alkaloid that has generated interest for its neuroprotective roles in brain pathology. However, the protective effect of trigonelline on cerebral ischemia/reperfusion (I/R) injury and the potential mechanism have not been fully evaluated. Our results showed that trigonelline pretreatment ameliorated oxygen-glucose deprivation/reperfusion (OGD/R)-induced hippocampal neurons injury. The OGD/R-caused reactive oxygen species (ROS) generation and decreased concentrations of superoxide dismutases (SOD) and glutathione peroxidase (GPx) were markedly attenuated by trigonelline. In addition, the increased levels of TNF-α, IL-6 and IL-1ß in OGD/R-induced hippocampal neurons were significantly decreased by trigonelline pretreatment. Trigonelline also suppressed caspase-3 activity and bax expression, and induced bcl-2 expression in OGD/R-induced hippocampal neurons. Furthermore, trigonelline induced the activation of PI3K/Akt pathway in hippocampal neurons exposed to OGD/R condition. Inhibition of PI3K/Akt signaling reversed the protective effects of trigonelline on OGD/R-induced hippocampal neurons injury. Taken together, these findings indicated that trigonelline protected hippocampal neurons from OGD/R-induced injury, which was mediated by the activation of PI3K/Akt signaling pathway.


Assuntos
Alcaloides/farmacologia , Glucose/administração & dosagem , Hipocampo/citologia , Neurônios/efeitos dos fármacos , Oxigênio/administração & dosagem , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Alcaloides/antagonistas & inibidores , Animais , Isquemia Encefálica , Sobrevivência Celular/efeitos dos fármacos , Cromonas/farmacologia , Inflamação , Morfolinas/farmacologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão , Transdução de Sinais/efeitos dos fármacos
18.
Biochem Biophys Res Commun ; 523(4): 987-992, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-31973819

RESUMO

In previous studies we demonstrated that zinc stimulates iron uptake in intestinal Caco-2 cells via Zinc-PI3K-IRP2-DMT1 axis. In the current study we investigated the effect of zinc on basolateral iron release and characterized the associated mechanisms. In Caco-2 cells grown on permeable supports, zinc induced iron transport and expression of DMT1, HEPH mRNA and protein, but not that of FPN1. LY294002, an inhibitor of PI3K, inhibited the zinc-induced iron transport, DMT1, HEPH mRNA and protein expression. In addition, LY294002 also inhibited the basal expression of HEPH and FPN1 resulting in blockade of iron egress from cells. In addition, siRNA-silencing of HEPH led to inhibition of both zinc-induced and basal iron transport. Conversely, TPEN, a chelator of zinc, inhibited iron uptake, DMT1, HEPH and FPN1 mRNA and protein expression. These results suggest that intestinal cell zinc status is a critical determinant of iron absorption and effects are mediated via activation of PI3K. Further, PI3K pathway appears to selectively modulate the expression of iron transporters and iron absorption, therefore this might serve as a therapeutic target in iron overload disorders.


Assuntos
Absorção Intestinal , Intestinos/fisiologia , Ferro/metabolismo , Proteínas de Membrana/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Zinco/farmacologia , Transporte Biológico/efeitos dos fármacos , Células CACO-2 , Cromonas/farmacologia , Etilenodiaminas/farmacologia , Inativação Gênica/efeitos dos fármacos , Humanos , Intestinos/efeitos dos fármacos , Morfolinas/farmacologia
19.
Chem Biol Interact ; 316: 108921, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31838053

RESUMO

Hyperproliferation and oxidative stress induced by hyperglycemia in mesangial cells plays crucial roles in the pathological process of diabetic nephropathy. Farrerol, isolated from rhododendron leaves, possesses broad anti-oxidative and anti-inflammatory properties towards several diseases, but its role in diabetic neuropathy remains unclear. The aim of this study was to evaluate the effects of farrerol in high glucose induced mesangial cell injury, and to explore underlying molecular mechanisms. Our results showed that high glucose in vitro conditions significantly stimulated cell proliferation, inflammatory cytokine secretion, extracellular matrix deposition, excessive oxidative stress, and NADPH oxidase activity in mesangial cells. Levels of NADPH oxidase 4 (Nox4) expression, ERK1/2 phosphorylation, and TGF-ß1/Smad2 activation were significantly induced by high glucose conditions in mesangial cells. Inversely, farrerol treatments at 40, 60, and 80 µM concentrations, dose-dependently alleviated this molecular damage by high glucose in mesangial cells. We also found that restoration of Nox4 expression abolished the protective effects of farrerol on high glucose-induced proliferation and reactive oxygen species generation. Furthermore, pretreatment with the Nox4 inhibitor diphenyliodonium or the ERK1/2 pathway inhibitor PD98059, displayed similar ameliorated effects of farrerol on high glucose-induced mesangial cell damage. Taken together, these data suggest that farrerol displays protective effects on high glucose induced mesangial cell injury, partly through the Nox4-mediated ROS/ERK1/2 signaling pathway. These observations may provide novel insights into the application of farrerol as a diabetic neuropathy treatment.


Assuntos
Cromonas/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , NADPH Oxidase 4/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Glucose/toxicidade , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Células Mesangiais/citologia , Células Mesangiais/efeitos dos fármacos , Células Mesangiais/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Fator de Crescimento Transformador beta/metabolismo
20.
Nat Prod Res ; 34(1): 137-152, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31631696

RESUMO

Natural compounds occurring throughout the world are scientifically and practically valuable because of their unique and beneficial properties to control a wide range of disorders in the human body. Chromones are attracting increasing attention as novel therapeutic agents due to their effective bioactivities for human health. Accordingly, the present overview article was designed to scan the biological and pharmacological performance of chromones, including their anti-inflammatory, anticancer, anti-oxidant, and anti-microbial activities.


Assuntos
Cromonas/uso terapêutico , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Cromonas/farmacologia , Humanos
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