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1.
Neuroimage ; 291: 120581, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38508293

RESUMO

Temporal interference (TI) stimulation, a novel non-invasive stimulation strategy, has recently been shown to modulate neural activity in deep brain regions of living mice. Yet, it is uncertain if this method is applicable to larger brains and whether the electric field produced under traditional safety currents can penetrate deep regions as observed in mice. Despite recent model-based simulation studies offering positive evidence at both macro- and micro-scale levels, the absence of electrophysiological data from actual brains hinders comprehensive understanding and potential application of TI. This study aims to directly measure the spatiotemporal properties of the interfered electric field in the rhesus monkey brain and to validate the effects of TI on the human brain. Two monkeys were involved in the measurement, with implantation of several stereo-electroencephalography (SEEG) depth electrodes. TI stimulation was applied to anesthetized monkeys using two pairs of surface electrodes at differing stimulation parameters. Model-based simulations were also conducted and subsequently compared with actual recordings. Additionally, TI stimulation was administered to patients with motor disorders to validate its effects on motor symptoms. Through the integration of computational electric field simulation with empirical measurements, it was determined that the temporally interfering electric fields in the deep central regions are capable of attaining a magnitude sufficient to induce a subthreshold modulation effect on neural signals. Additionally, an improvement in movement disorders was observed as a result of TI stimulation. This study is the first to systematically measure the TI electric field in living non-human primates, offering empirical evidence that TI holds promise as a more focal and precise method for modulating neural activities in deep regions of a large brain. This advancement paves the way for future applications of TI in treating neuropsychiatric disorders.


Assuntos
Encéfalo , Estimulação Encefálica Profunda , Humanos , Animais , Camundongos , Encéfalo/fisiologia , Eletrodos , Simulação por Computador , Eletroencefalografia , Primatas , Estimulação Encefálica Profunda/métodos
2.
Saudi Pharm J ; 31(7): 1219-1228, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37293563

RESUMO

Benign prostatic hyperplasia (BPH) is a common urinary disease among the elderly, characterized by abnormal prostatic cell proliferation. Neferine is a dibenzyl isoquinoline alkaloid extracted from Nelumbo nucifera and has antioxidant, anti-inflammatory and anti-prostate cancer effects. The beneficial therapeutic effects and mechanism of action of neferine in BPH remain unclear. A mouse model of BPH was generated by subcutaneous injection of 7.5 mg/kg testosterone propionate (TP) and 2 or 5 mg/kg neferine was given orally for 14 or 28 days. Pathological and morphological characteristics were evaluated. Prostate weight, prostate index (prostate/body weight ratio), expression of type Ⅱ 5α-reductase, androgen receptor (AR) and prostate specific antigen were all decreased in prostate tissue of BPH mice after administration of neferine. Neferine also downregulated the expression of pro-caspase-3, uncleaved PARP, TGF-ß1, TGF-ß receptor Ⅱ (TGFBR2), p-Smad2/3, N-cadherin and vimentin. Expression of E-cadherin, cleaved PARP and cleaved caspase-3 was increased by neferine treatment. 1-100 µM neferine with 1 µM testosterone or 10 nM TGF-ß1 were added to the culture medium of the normal human prostate stroma cell line, WPMY-1, for 24 h or 48 h. Neferine inhibited cell growth and production of reactive oxygen species (ROS) in testosterone-treated WPMY-1 cells and regulated the expression of androgen signaling pathway proteins and those related to epithelial-mesenchymal transition (EMT). Moreover, TGF-ß1, TGFBR2 and p-Smad2/3, N-cadherin and vimentin expression were increased but E-cadherin was decreased after 24 h TGF-ß1 treatment in WPMY-1 cells. Neferine reversed the effects of TGF-ß1 treatment in WPMY-1 cells. Neferine appeared to suppress prostate growth by regulating the EMT, AR and TGF-ß/Smad signaling pathways in the prostate and is suggested as a potential agent for BPH treatment.

3.
Anticancer Agents Med Chem ; 23(12): 1457-1468, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37005535

RESUMO

INTRODUCTION: Prostate cancer is the second-leading cause of cancer death in men. Sinularin is a soft coralsderived natural compound that has anticancer activity in many cancer cells. However, the pharmacological action of sinularin in prostate cancer is unclear. AIM: The aim of the study is to examine the anticancer effects of sinularin in prostate cancer cells. METHODS: We explored the anticancer effects of sinularin on the prostate cancer cell lines, PC3, DU145, and LNCaP, by MTT, Transwell assay, wound healing, flow cytometry, and western blotting. RESULTS: Sinularin inhibited the cell viability and colony formation of these cancer cells. Furthermore, sinularin inhibited testosterone-induced cell growth in LNCaP cells by downregulating the protein expression levels of androgen receptor (AR), type Ⅱ 5α-reductase, and prostate-specific antigen (PSA). Sinularin significantly attenuated the invasion and migration ability of PC3 and DU145 cells, with or without TGF-ß1 treatment. Sinularin inhibited epithelialmesenchymal transition (EMT) in DU145 cells after 48 h of treatment by regulating the protein expression levels of Ecadherin, N-cadherin, and vimentin. Sinularin induced apoptosis, autophagy, and ferroptosis by regulating the protein expression levels of Beclin-1, LC3B, NRF2, GPX4, PARP, caspase-3, caspase-7, caspase-9, cleaved-PARP, Bcl-2, and Bax. Moreover, intracellular reactive oxygen species (ROS) were increased but glutathione was decreased after sinularin treatment in PC3, DU145 and LNCaP cells. CONCLUSION: Sinularin regulated the androgen receptor signaling pathway and triggered apoptosis, autophagy, and ferroptosis in prostate cancer cells. In conclusion, the results indicated that sinularin may be a candidate agent for human prostate cancer and need further study for being applied to human.


Assuntos
Ferroptose , Neoplasias da Próstata , Masculino , Humanos , Receptores Androgênicos/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Linhagem Celular Tumoral , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Apoptose , Estresse Oxidativo , Proliferação de Células , Autofagia
4.
J Pharm Pharmacol ; 74(11): 1640-1650, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-35704277

RESUMO

OBJECTIVES: Temporal lobe epilepsy (TLE) is a common and intractable form of epilepsy. There is a strong need to better understand molecular events underlying TLE and to find novel therapeutic agents. Here we aimed to investigate the role of Clock and ferroptosis in regulating TLE. METHODS: TLE model was established by treating mice with kainic acid (KA). Regulatory effects of the Clock gene on KA-induced seizures and ferroptosis were evaluated using Clock knockout (Clock-/-) mice. mRNA and protein levels were determined by quantitative real-time PCR and western blotting, respectively. Ferroptosis was assessed by measuring the levels of iron, GSH and ROS. Transcriptional regulation was studied using a combination of luciferase reporter, mobility shift and chromatin immunoprecipitation (ChIP) assays. KEY FINDINGS: We found that Clock ablation exacerbated KA-induced seizures in mice, accompanied by enhanced ferroptosis in the hippocampus. Clock ablation reduced the hippocampal expression of GPX4 and PPAR-γ, two ferroptosis-inhibitory factors, in mice and in N2a cells. Moreover, Clock regulates diurnal expression of GPX4 and PPAR-γ in mouse hippocampus and rhythmicity in KA-induced seizures. Consistent with this finding, Clock overexpression up-regulated GPX4 and PPAR-γ and protected against ferroptosis in N2a cells. In addition, luciferase reporter, mobility shift and ChIP assays showed that CLOCK trans-activated Gpx4 and Ppar-γ through direct binding to the E-box elements in the gene promoters. CONCLUSION: CLOCK protects against KA-induced seizures through increased expression of GPX4 and PPAR-γ and inhibition of ferroptosis.


Assuntos
Proteínas CLOCK , Epilepsia do Lobo Temporal , Ferroptose , Animais , Camundongos , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/metabolismo , Ácido Caínico/efeitos adversos , PPAR gama , Convulsões/induzido quimicamente , Convulsões/genética , Proteínas CLOCK/genética , Camundongos Knockout
5.
Oncol Lett ; 23(6): 187, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35527779

RESUMO

6-Gingerol is a bioactive compound isolated from Zingiber officinale. 6-Gingerol has been shown to have anticancer effects in numerous types of cancer cell. The mechanisms underlying the anticancer effect of 6-Gingerol in prostate cancer requires investigation. In the present study, the effect on cell viability of 6-Gingerol on LNCaP, PC3 and DU145 prostate cancer cells were determined using the MTT and colony formation assays. 6-Gingerol significantly inhibited cell migration, adhesion and invasion in LPS-stimulated and LPS-unstimulated prostate cancer cells. Furthermore, these changes were accompanied by alterations in the protein expression levels of epithelial-mesenchymal transition biomarkers, including E-cadherin, N-cadherin, Vimentin and zonula occludens-1. 6-Gingerol also induced autophagy by significantly increasing LC3B-II and Beclin-1 protein expression levels in prostate cancer cells. Combining 6-Gingerol with LY294002, an autophagy inhibitor, significantly increased cell survival in DU145 cells. Furthermore, 6-Gingerol significantly decreased the protein expression levels of glutathione (GSH) peroxidase 4 and nuclear factor erythroid 2-related factor 2 in prostate cancer cells. Reactive oxygen species (ROS) levels were significantly increased but GSH levels were decreased following 6-Gingerol treatment in prostate cancer cells. Co-treatment with the ferroptosis inhibitor, ferrostatin-1, significantly increased cell viability and significantly decreased ROS levels in 6-Gingerol-treated cells. These results suggested that 6-Gingerol may have inhibited prostate cell cancer viability via the regulation of autophagy and ferroptosis. In addition, 6-Gingerol inhibited cell migration, adhesion and invasion via the regulation of EMT-related protein expression levels in LPS-stimulated and LPS-unstimulated prostate cancer cells. In conclusion, 6-Gingerol may induce protective autophagy, autophagic cell death and ferroptosis-mediated cell death in prostate cancer cells. These findings may provide a strategy for the treatment and prevention of prostate cancer.

6.
Biochem Pharmacol ; 193: 114807, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34673015

RESUMO

The molecular events underlying aristolochic acid (AA) nephropathy are poorly understood, and specific therapies for treatment of AA nephropathy are still lacking. Here we aimed to investigate a potential role of REV-ERBα and ferroptosis in renal injury induced by aristolochic acid I (AAI), a typical AA. The regulatory effects of REV-ERBα on AAI-induced renal injury were determined using kidney-specific Rev-erbα knockout mice. Ferroptosis was assessed based on measurements of iron, GSH, and GPX4. Targeted antagonism of REV-ERBα to alleviate AAI-induced renal injury and ferroptosis was assessed using the small molecule antagonist SR8278. mRNAs and proteins were quantified by qPCR and Western blotting, respectively. We first showed that REV-ERBα was upregulated and its target BMAL1 was downregulated in the kidney of mice with AAI nephropathy. Upregulation of REV-ERBα protein was confirmed in aristolactam I (ALI, a nephrotoxic metabolite of AAI)-treated mRTECs. We also observed enhanced ferroptosis (known to be regulated by REV-ERBα) in mice with AAI nephropathy and in ALI-treated mRTECs. Kidney-specific knockout of Rev-erbα reduced the sensitivity of mice to AAI-induced ferroptosis and renal injury. Furthermore, knockdown of Rev-erbα by siRNA or SR8278 (a REV-ERBα antagonist) treatment attenuated ALI-induced ferroptosis in mRTECs. Moreover, REV-ERBα antagonism by SR8278 alleviated ferroptosis and renal injury caused by AAI in mice. In conclusion, we identify REV-ERBα as a regulator of AAI-induced renal injury via promoting ferroptosis. Targeting REV-ERBα may represent a promising approach for management of AAI nephropathy.


Assuntos
Ácidos Aristolóquicos/toxicidade , Ferroptose/efeitos dos fármacos , Isoquinolinas/farmacologia , Nefropatias/induzido quimicamente , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/metabolismo , Tiofenos/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Nefropatias/tratamento farmacológico , Túbulos Renais/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estrutura Molecular , Membro 1 do Grupo D da Subfamília 1 de Receptores Nucleares/genética
7.
Xenobiotica ; 51(10): 1101-1109, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34382487

RESUMO

miR-199a-5p is an important regulator of many biological processes. However, whether and how CYP enzymes are regulated by miR-199a-5p are unknown. Here, we aimed to investigate the potential role of mmu-miR-199a-5p in regulating CYP2 enzymes.Regulatory effects of mmu-miR-199a-5p on CYP expression were assessed in mouse AML-12 hepatocytes. The metabolic activity of CYP2B10 was probed using cyclophosphamide (CPA) as a specific substrate. The regulatory mechanism was investigated using combined luciferase reporter assays and chromatin immunoprecipitation.Of several important drug-metabolizing CYPs, mmu-miR-199a-5p significantly increased the mRNA levels of Cyp2a10, Cyp2c29, and Cyp2j5 in AML-12 cells with Cyp2a10 altered the most. Consistently, mmu-miR-199a-5p enhanced the expression of CYP2B10 protein and cellular metabolism of CPA. Based on database analysis, Cyp2b10 was not a direct target gene of mmu-miR-199a-5p. Thus, a mediator is necessary for the miRNA regulation of CYP2B10. We found that E4BP4 repressed Cyp2b10 transcription and expression through specific binding to a D-box element in the gene promoter. Moreover, mmu-miR-199a-5p inhibited the expression of E4bp4 at the posttranscriptional level by directly targeting the 59-65 nt segment in its 3'-UTR.In conclusion, mmu-miR-199a-5p positively regulates CYP2B10 expression through inhibiting its repressor E4BP4. Our findings may provide an increased understanding of the complex regulatory pathways for CYP2B10.


Assuntos
Leucemia Mieloide Aguda , MicroRNAs , Regiões 3' não Traduzidas , Animais , Hepatócitos , Camundongos , MicroRNAs/genética , RNA Mensageiro
8.
Pharmazie ; 76(5): 225-231, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33964997

RESUMO

Neferine, liensinine, and isoliensinine are bisbenzylisoquinoline alkaloids extracted from seed-embryos of Nelumbo nucifera Gaertn. In this study, we evaluated the anticancer activities and mechanism of action of these natural products in prostate cancer cells by MTT, wound healing, ELISA and Western blotting. Neferine, liensinine, and isoliensinine showed growth inhibition and displayed a significant anti-migration activity in prostate cancer cells. They induced apoptosis and autophagy by activating cleaved caspase-9, cleaved PAPR, Bax, LC3B-II, but decreased Bcl-2 and PARP protein expression in LNCaP cells 24 h after treatments. The apoptotic and cytotoxic effects of neferine, liensinine, and isoliensinine were significantly attenuated in the presence of the caspase inhibitor, Z-VAD-FMK. However, the effects were enhanced in the presence of Akt inhibitor (MK2206) and PI3K inhibitor (LY294002). Moreover, neferine, liensinine, and isoliensinine also downregulated the protein expression of androgen receptor, prostate-specific antigen, and type II 5-α-reductase. These results demonstrated that these bisbenzylisoquinoline alkaloids have the potential as promising therapeutics agents. They induced apoptosis via inactivation with the PI3K/AKT signal pathway.


Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Antagonistas de Receptores de Andrógenos/farmacologia , Benzilisoquinolinas/farmacologia , Isoquinolinas/farmacologia , Fenóis/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Clorometilcetonas de Aminoácidos/farmacologia , Antagonistas de Androgênios/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Benzilisoquinolinas/química , Produtos Biológicos/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cromonas/farmacologia , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Isoquinolinas/química , Masculino , Morfolinas/farmacologia , Nelumbo/química , Fenóis/química , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
9.
Entropy (Basel) ; 23(2)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573210

RESUMO

Android devices are currently widely used in many fields, such as automatic control, embedded systems, the Internet of Things and so on. At the same time, Android applications (apps) always use multiple permissions, and permissions can be abused by malicious apps that disclose users' privacy or breach the secure storage of information. FlowDroid has been extensively studied as a novel and highly precise static taint analysis for Android applications. Aiming at the problem of complex detection and false alarms in FlowDroid, an improved static detection method based on feature permission and risk rating is proposed. Firstly, the Chi-square test is used to extract correlated permissions related to malicious apps, and mutual information is used to cluster the permissions to generate feature permission clusters. Secondly, risk calculation method based on permissions and combinations of permissions are proposed to identify dangerous data flows. Experiments show that this method can significantly improve detection efficiency while maintaining the accuracy of dangerous data flow detection.

10.
Front Pharmacol ; 11: 01079, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33041783

RESUMO

BACKGROUND: Diazepam is a benzodiazepine drug used to treat anxiety, insomnia, and muscle spasms. Imperatorin is a phytochemical isolated from medicinal plants and is widely used in herbal medicine. The aim of this study was to investigate the interactions between imperatorin and diazepam in vitro and in vivo and to provide evidence-based guidance for the safe clinical use of the drug. METHODS: In vitro inhibition of imperatorin was assessed by incubating rat liver microsomes with diazepam to determine IC50 values and the type of inhibition. For in vivo assessment, six rats were pretreated with 50 mg/kg imperatorin for two weeks, six were administered saline, and a single dose of 10 mg/kg diazepam was administered orally to both groups 30 min after the administration of imperatorin. RESULTS: Imperatorin inhibited the in vitro metabolism of diazepam via the competitive mechanism of CYP450. The IC50 values of imperatorin to nordazepam and temazepam were 1.54 µM and 1.80 µM, respectively. The inhibitory constant values for temazepam and nordazepam were 1.24 µM and 1.29 µM, respectively. Long-term administration of imperatorin significantly increased the AUC(0-12h), AUC(0-∞), and Cmax of diazepam, while Vz/F and CLz/F were decreased significantly (P < 0.05). In turn, the AUC(0-12h), AUC(0-∞), and Cmax of nordazepam and temazepam decreased significantly, and Vz/F and CLz/F increased significantly (P < 0.05). CONCLUSIONS: This study demonstrates that imperatorin inhibits the metabolism of diazepam both in vitro and in vivo. These results indicated that more attention should be paid when taking diazepam together with food or herbs containing IMP, although further investigation is still needed.

11.
J Neurosci Methods ; 341: 108776, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32479971

RESUMO

BACKGROUND: A major difficulty for the asynchronous brain-computer interface (BCI) lies in the accurate recognition of the control and idle states. Although subject's attention level was found to be different in these states, the validity of recognizing them using attention features has not been studied. NEW METHODS: This paper proposed a novel Individualized Frequency Band based Optimized Complex Network (IFB-OCN) method to enhance the performance of discriminating the control and idle states. The IFB-OCN method extracted the attention features from a single FPz channel, selected the first three individualized frequency bands with the highest accuracies, and integrated the features of these bands for classification. RESULTS: The performance was evaluated using a steady-state visual evoked potential (SSVEP)-based BCI task. In the offline evaluation, the IFB-OCN method achieved the highest average accuracy of 93.5 % with the data length of 4 s, and achieved the highest information transfer rate (ITR) of 47.3 bits/min with the data length of 0.5 s. In the simulated online evaluation, the IFB-OCN method obtained a true positive rate (TPR) of 89.8 % and a true negative rate (TNR) of 86.2 %. COMPARISON WITH EXISTING METHODS: The proposed IFB-OCN method recognized the control and idle states using a single FPz channel rather than the occipital channels, and outperformed the existing algorithms in the accuracy of detecting the attention level. CONCLUSIONS: These results demonstrate that the proposed IFB-OCN method is efficient in recognizing the idle state and has a great potential for enhancing the asynchronous BCIs.


Assuntos
Interfaces Cérebro-Computador , Potenciais Evocados Visuais , Algoritmos , Eletroencefalografia , Estimulação Luminosa , Reconhecimento Psicológico
12.
Pharmazie ; 74(11): 675-679, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31739836

RESUMO

Docosahexaenoic acid (DHA) is rich in fish oil with many pharmacological impacts such as anti-inflammation and anti-cancer activities. In the present study, we aimed to investigate the inhibitory effects of DHA on the invasion and inflammation in prostate cancer cells. The cytotoxicity of DHA with or without lipopolysaccharides (LPS) treatment was evaluated by MTT assay. The invasion and wound healing assays were used to determine the roles of DHA in cell migration and invasion after LPS treatment. The expression levels of IL-6 and IL-8 were detected using ELISA assay. The protein expression was investigated by Western blotting. DHA exhibited significant cytotoxicity at the concentration of 100 µM in PC3 cells. Exposure to DHA (6, 12 and 25 µM) dose-dependently inhibited invasion and wound closure potential in PC3 cells after LPS treatment. DHA dose-dependently downregulated LPS-induced expression levels of IL-6 and IL-8. In addition, the LPS-induced protein levels of p-AKT and COX-2 were suppressed by DHA treatment. Our results indicate that low doses of DHA effectively inhibit metastasis by decreasing IL-6, IL-8, p-AKT and COX-2 expression levels after LPS treatment.


Assuntos
Ácidos Docosa-Hexaenoicos/farmacologia , Inflamação/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/administração & dosagem , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/patologia , Lipopolissacarídeos , Masculino , Metástase Neoplásica/prevenção & controle , Células PC-3 , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
13.
Cell Death Dis ; 10(8): 606, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31406104

RESUMO

Triple-negative breast cancer (TNBC), defined as a tumor subtype that lacks ER, PR, and HER2, shows a poor prognosis due to its aggressive tumor biology and limited treatment options. Deregulation of Aurora kinase A (Aur-A), a member of the mitotic serine/threonine Aurora kinase family, and overactivation of the mTOR pathway commonly occur in multiple cancer types. We previously found that Aur-A activated the mTOR pathway and inhibited autophagy activity in breast cancer cell models. Whether and how Aur-A regulates mTOR in TNBC are still unclear. Here, we found that Aur-A and p-mTOR are highly expressed and positively associated with each other in TNBC cells and tissues. Inhibition or knockdown of Aur-A decreased p-mTOR and suppressed cell proliferation and migration, whereas overexpression of Aur-A increased p-mTOR levels and promoted cell proliferation and migration, which was significantly abrogated by simultaneous silencing of mTOR. Intriguingly, overexpression of Aur-A enhanced the expression of p-mTOR and p-ERK1/2, and silencing or inhibition of ERK1/2 blocked Aur-A-induced p-mTOR. However, silencing or inhibition of mTOR failed to reverse Aur-A-induced ERK1/2, indicating that Aur-A/ERK1/2/mTOR forms an oncogenic cascade in TNBC. We finally found that double inhibition of Aur-A and mTOR showed significant synergistic effects in TNBC cell lines and a xenograft model, indicating that Aur-A and mTOR are potential therapeutic targets in the TNBC subtype.


Assuntos
Aurora Quinase A/metabolismo , Progressão da Doença , Sistema de Sinalização das MAP Quinases , Mutações Sintéticas Letais , Serina-Treonina Quinases TOR/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Animais , Antineoplásicos/farmacologia , Aurora Quinase A/antagonistas & inibidores , Azepinas/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Ativação Enzimática/efeitos dos fármacos , Feminino , Inativação Gênica/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Nus , Invasividade Neoplásica , Pirimidinas/farmacologia , Sirolimo/farmacologia , Mutações Sintéticas Letais/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Comput Intell Neurosci ; 2019: 2167871, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30944553

RESUMO

A neurofeedback system adjusting an individual's attention is an effective treatment for attention-deficit/hyperactivity disorder (ADHD). In current studies, an accurate measure of the level of human attention is one of the key issues that arouse much interest. This paper proposes a novel optimized complex network method (OCNM) for measuring an individual's attention level using single-electrode electroencephalography (EEG) signals. A time-delay embedding algorithm was used to reconstruct EEG data epochs into nodes of the OCNM network. Euclidean distances were calculated between each two nodes to decide edges of the network. Three key parameters influencing OCNM, i.e., delaying time, embedding dimension, and connection threshold, were optimized for each individual. The average degree and clustering coefficient of the constructed network were extracted as a feature vector and were classified into two patterns of concentration and relaxation using an LDA classifier. In the offline experiments of six subjects, the classification performance was tested and compared with an attention meter method (AMM) and an α + ß + δ + θ + R method. The experimental results showed that the proposed OCNM achieved the highest accuracy rate (80.67% versus 70.58% and 68.88%). This suggests that the proposed method can potentially be used for EEG-based neurofeedback systems with a single electrode.


Assuntos
Atenção/fisiologia , Encéfalo/fisiologia , Eletroencefalografia , Neurorretroalimentação/fisiologia , Algoritmos , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Eletrodos , Eletroencefalografia/métodos , Humanos
15.
Front Mol Neurosci ; 10: 365, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29163040

RESUMO

In the brain, de novo gene expression driven by learning-associated neuronal activities is critical for the formation of long-term memories. However, the signaling machinery mediating neuronal activity-induced gene expression, especially the rapid transcription of immediate-early genes (IEGs) remains unclear. Cyclin-dependent kinases (Cdks) are a family of serine/threonine kinases that have been firmly established as key regulators of transcription processes underling coordinated cell cycle entry and sequential progression in nearly all types of proliferative cells. Cdk7 is a subunit of transcriptional initiation factor II-H (TFIIH) and the only known Cdk-activating kinase (CAK) in metazoans. Recent studies using a novel Cdk7 specific covalent inhibitor, THZ1, revealed important roles of Cdk7 in transcription regulation in cancer cells. However, whether Cdk7 plays a role in the regulation of transcription in neurons remains unknown. In this study, we present evidence demonstrating that, in post-mitotic neurons, Cdk7 activity is positively correlated with neuronal activities in cultured primary neurons, acute hippocampal slices and in the brain. Cdk7 inhibition by THZ1 significantly suppressed mRNA levels of IEGs, selectively impaired long-lasting synaptic plasticity induced by 4 trains of high frequency stimulation (HFS) and prevented the formation of long-term memories.

16.
Artigo em Inglês | MEDLINE | ID: mdl-29037923

RESUMO

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

17.
Cell Physiol Biochem ; 43(1): 94-107, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848145

RESUMO

BACKGROUND/AIMS: CyclinG1 (CycG1) is frequently overexpressed in solid tumors and overexpression of CycG1 promotes cell survival upon paclitaxel exposure by inducing polyploidy. Whether and how CycG1 regulates polyploidization caused by small molecular targeted inhibitors remains unclear. METHODS: Immunohistochemistry and immunoblotting were utilized to examine protein expression. Cell proliferation was measured by ATPlite assay, and cell cycle distribution and apoptosis were measured by flow cytometry and/or DNA fragmentation assays. RESULTS: Overexpression of CycG1 in breast cancer cells caused apoptosis-resistant polyploidy upon treatment with Aurora kinase inhibitor, ZM447439 (ZM). Addition of ABT-263, a small-molecule BH3 mimetic, to ZM, produced a synergistic loss of cell viability with greater sustained tumor growth inhibition in breast cancer cell lines. Decrease of Mcl-1 and increase of NOXA caused by ZM treatment, were responsible for the synergy. Furthermore, CycG1 was highly expressed in Triple-Negative-Breast-Cancer patients treated with paclitaxel and was paralleled by decreased cell survival. CONCLUSION: CycG1 is a crucial factor in ZM-induced polyploidy resistance, and ABT-263/ZM combination hold therapeutic utility in the CycG1-amplified subset of breast cancer and CycG1, thus, is a promising target in breast cancer.


Assuntos
Ciclina G1/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Adulto , Compostos de Anilina/toxicidade , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Benzamidas/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclina G1/antagonistas & inibidores , Ciclina G1/genética , Feminino , Humanos , Células MCF-7 , Pessoa de Meia-Idade , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Poliploidia , Prognóstico , Quinazolinas/farmacologia , Interferência de RNA , Sulfonamidas/toxicidade , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/mortalidade , Proteína bcl-X/metabolismo
18.
Biomed Pharmacother ; 90: 531-541, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28402922

RESUMO

Triptolide (TP), a major active and toxic ingredient isolated from the traditional Chinese herb Tripterygium wilfordii Hook f. (TWHF). A widespread application of TP raises the question on the safety of its use in clinical settings. The metabolism of TP is mediated by hepatic cytochrome P450s, and a strong correlation exists between TP toxicity and CPY3A. Toxicity of TP and the molecular mechanisms of its toxic effects have been studied in recent years. Studies have demonstrated that TP exposure results in injury of various organs, including the liver, kidney, testes, ovary, and heart in animals and even in humans, according to clinical case reports. Moreover, on the cellular level, TP has been reported to be associated with diverse toxic effects, encompassing membrane damage, mitochondrial disruption, metabolism dysfunction, endoplasmic reticulum stress, oxidative stress, apoptosis and autophagy. This review presents an overview of the current findings related to TP toxicity with an emphasis on biological targets and the molecular mechanisms that may be involved, thus providing a systematic understanding of the mechanisms by which TP affects cells and tissues in vitro and in vivo.


Assuntos
Diterpenos/efeitos adversos , Fenantrenos/efeitos adversos , Tripterygium/efeitos adversos , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Compostos de Epóxi/efeitos adversos , Humanos , Mitocôndrias/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos
19.
Phys Chem Chem Phys ; 17(1): 159-65, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25372713

RESUMO

The ion-migration mechanism of Na3V2(PO4)2F3 is investigated in Na3V2(PO4)2F3-Li hybrid-ion batteries for the first time through a combined computational and experimental study. There are two Na sites namely Na(1) and Na(2) in Na3V2(PO4)2F3, and the Na ions at Na(2) sites with 0.5 occupation likely extract earlier to form Na2V2(PO4)2F3. The structural reorganisation is suggested to make a stable configuration of the remaining ions at the centre of Na(1) sites. After the extraction of the second Na ion, the last ion prefers to change occupation from 1 to 0.5 to occupy two Na(2) sites. The insertion of predominant Li ions also should undergo structural reorganization when the first Li ion inserts into the centre of Na(1) site theoretically forming NaLiV2(PO4)2F3, and the second ion inserts into two Na(2) sites to form NaLi2V2(PO4)2F3. More than a 0.3 Li ion insertion would take place in the applied voltage range by increasing the number of sites occupied rather than occupy the vacancy in triangular prismatic sites. An improved solution-based carbothermal reduction methodology makes Na3V2(PO4)2F3 exhibit excellent C-rate and cycling performances, of which the Li-inserted voltage is evaluated by first principles calculations.

20.
Langmuir ; 30(41): 12438-46, 2014 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-25212063

RESUMO

The electrochemical properties of Na3V2(PO4)2F3 cathode utilized in the sodium ion battery are investigated, and the ion migration mechanisms are proposed as combined via the first principles calculations. Two different Na sites, namely, the Na(1) and Na(2) sites, could cause two sodium ions of Na3V2(PO4)2F3 to be extracted or inserted by a two-step electrochemical process accompanied by structural reorganization that could be responsible for the redox reaction of V(3+/4+). Because the calculated average voltage (V(avg)) of the second charging plateau is 4.04 V for the optimized system but 4.38 V for the unoptimized one, the reorganization of the cathode system can make a stable configuration and lower the extraction energy. Three designed pathways for sodium ions along the x, y, z directions in Na3V2(PO4)2F3, known as a 3D ions transport tunnel, have activation energies (Ea) of 0.449, 0.2, and 0.323 eV, respectively, by using DFT calculations, demonstrating the different feasibilities of the migration directions.

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