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1.
Biomed Eng Online ; 23(1): 57, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902671

RESUMO

OBJECTIVE: Our objective was to create a machine learning architecture capable of identifying obstructive sleep apnea (OSA) patterns in single-lead electrocardiography (ECG) signals, exhibiting exceptional performance when utilized in clinical data sets. METHODS: We conducted our research using a data set consisting of 1656 patients, representing a diverse demographic, from the sleep center of China Medical University Hospital. To detect apnea ECG segments and extract apnea features, we utilized the EfficientNet and some of its layers, respectively. Furthermore, we compared various training and data preprocessing techniques to enhance the model's prediction, such as setting class and sample weights or employing overlapping and regular slicing. Finally, we tested our approach against other literature on the Apnea-ECG database. RESULTS: Our research found that the EfficientNet model achieved the best apnea segment detection using overlapping slicing and sample-weight settings, with an AUC of 0.917 and an accuracy of 0.855. For patient screening with AHI > 30, we combined the trained model with XGBoost, leading to an AUC of 0.975 and an accuracy of 0.928. Additional tests using PhysioNet data showed that our model is comparable in performance to existing models regarding its ability to screen OSA levels. CONCLUSIONS: Our suggested architecture, coupled with training and preprocessing techniques, showed admirable performance with a diverse demographic dataset, bringing us closer to practical implementation in OSA diagnosis. Trial registration The data for this study were collected retrospectively from the China Medical University Hospital in Taiwan with approval from the institutional review board CMUH109-REC3-018.


Assuntos
Eletrocardiografia , Aprendizado de Máquina , Processamento de Sinais Assistido por Computador , Síndromes da Apneia do Sono , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes da Apneia do Sono/diagnóstico , Feminino , Adulto , Idoso , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/fisiopatologia
2.
Int J Med Sci ; 21(4): 656-663, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464824

RESUMO

Purpose: With advances in medical technology, the average lifespan has increased, leading to a growing significance of idiopathic normal pressure hydrocephalus (iNPH), particularly in the elderly population. Most patients with iNPH have been treated either with ventriculo-peritoneal shunts (VPS) or conservative measures. However, lumbo-peritoneal shunts (LPS) have emerged as an alternative treatment option for iNPH in recent decades, extensive research still lacks comparing outcomes with LPS to those with VPS or non-surgical treatment. The aim of the resent study is to disclose the long-term therapeutic outcomes of LPS, VPS, and non-shunting in patients with iNPH. Methods: We used the National Health Insurance Research Database in Taiwan to assess the long-term outcomes of these treatment options. We enrolled 5,537 iNPH patients who received shunting surgery, of which 5,254 were VPS and 283 were LPS. To compare the difference between each group, matching was conducted by propensity score matching using a 1:1 ratio based on LPS patients. Primary outcomes included death and major adverse cardiovascular events (MACEs) Results: Our findings show that VPS resulted in significantly more MACEs than non-surgical treatment (Odds ratio: 1.83, 95% confidence interval: 1.16-2.90). In addition, both VPS and LPS groups had significantly lower overall mortality rates than non-shunting group. Moreover, LPS had lower overall mortality but similar MACEs rates to VPS. Conclusions: Based on these findings, we propose that the LPS is preferable to the VPS, and surgical treatment should be considered the primary choice over conservative treatment unless contraindications are present.


Assuntos
Hidrocefalia de Pressão Normal , Humanos , Idoso , Hidrocefalia de Pressão Normal/epidemiologia , Hidrocefalia de Pressão Normal/cirurgia , Estudos Retrospectivos , Lipopolissacarídeos , Derivação Ventriculoperitoneal/efeitos adversos , Derivação Ventriculoperitoneal/métodos , Procedimentos Cirúrgicos Vasculares , Resultado do Tratamento
3.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38892294

RESUMO

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is responsible for the current coronavirus disease pandemic. With the rapid evolution of variant strains, finding effective spike protein inhibitors is a logical and critical priority. Angiotensin-converting enzyme 2 (ACE2) has been identified as the functional receptor for SARS-CoV-2 viral entry, and thus related therapeutic approaches associated with the spike protein-ACE2 interaction show a high degree of feasibility for inhibiting viral infection. Our computer-aided drug design (CADD) method meticulously analyzed more than 260,000 compound records from the United States National Cancer Institute (NCI) database, to identify potential spike inhibitors. The spike protein receptor-binding domain (RBD) was chosen as the target protein for our virtual screening process. In cell-based validation, SARS-CoV-2 pseudovirus carrying a reporter gene was utilized to screen for effective compounds. Ultimately, compounds C2, C8, and C10 demonstrated significant antiviral activity against SARS-CoV-2, with estimated EC50 values of 8.8 µM, 6.7 µM, and 7.6 µM, respectively. Using the above compounds as templates, ten derivatives were generated and robust bioassay results revealed that C8.2 (EC50 = 5.9 µM) exhibited the strongest antiviral efficacy. Compounds C8.2 also displayed inhibitory activity against the Omicron variant, with an EC50 of 9.3 µM. Thus, the CADD method successfully discovered lead compounds binding to the spike protein RBD that are capable of inhibiting viral infection.


Assuntos
Enzima de Conversão de Angiotensina 2 , Antivirais , Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Humanos , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , Antivirais/química , Enzima de Conversão de Angiotensina 2/metabolismo , Enzima de Conversão de Angiotensina 2/química , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Simulação de Acoplamento Molecular , Descoberta de Drogas/métodos , Ligação Proteica , COVID-19/virologia , Desenho de Fármacos , Internalização do Vírus/efeitos dos fármacos
4.
J Enzyme Inhib Med Chem ; 38(1): 2166039, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36683274

RESUMO

Inhibiting a specific target in cancer cells and reducing unwanted side effects has become a promising strategy in pancreatic cancer treatment. MAP4K4 is associated with pancreatic cancer development and correlates with poor clinical outcomes. By phosphorylating MKK4, proteins associated with cell apoptosis and survival are translated. Therefore, inhibiting MAP4K4 activity in pancreatic tumours is a new therapeutic strategy. Herein, we performed a structure-based virtual screening to identify MAP4K4 inhibitors and discovered the compound F389-0746 with a potent inhibition (IC50 120.7 nM). The results of kinase profiling revealed that F389-0746 was highly selective to MAP4K4 and less likely to cause side effects. Results of in vitro experiments showed that F389-0746 significantly suppressed cancer cell growth and viability. Results of in vivo experiments showed that F389-0746 displayed comparable tumour growth inhibition with the group treated with gemcitabine. These findings suggest that F389-0746 has promising potential to be further developed as a novel pancreatic cancer treatment.


Assuntos
Antineoplásicos , Neoplasias Pancreáticas , Inibidores de Proteínas Quinases , Proteínas Serina-Treonina Quinases , Humanos , Linhagem Celular Tumoral , Gencitabina/química , Gencitabina/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular , Neoplasias Pancreáticas/enzimologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Simulação por Computador , Neoplasias Pancreáticas
5.
J Enzyme Inhib Med Chem ; 38(1): 2212326, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37190931

RESUMO

Class II histone deacetylases (HDACs) are considered as potential targets to treat Alzheimer's disease (AD). Previously, C-3 substituted phenothiazine-containing compounds with class II HDAC-inhibiting activities was found to promote neurite outgrowth. This study replaced phenothiazine moiety with phenoxazine that contains many C-3 and C-4 substituents. Some resulting compounds bearing the C-4 substituent on a phenoxazine ring displayed potent class II HDAC inhibitory activities. Structure-activity relationship (SAR) of these compounds that inhibited HDAC isoenzymes was disclosed. Molecular modelling analysis demonstrates that the potent activities of C-4 substituted compounds probably arise from π-π stacked interactions between these compounds and class IIa HDAC enzymes. One of these, compound 7d exhibited the most potent class II HDAC inhibition (IC50= 3-870 nM). Notably, it protected neuron cells from H2O2-induced neuron damage at sub-µM concentrations, but with no significant cytotoxicity. These findings show that compound 7d is a lead compound for further development of anti-neurodegenerative agents.


Assuntos
Antineoplásicos , Ácidos Hidroxâmicos , Ácidos Hidroxâmicos/farmacologia , Inibidores de Histona Desacetilases/farmacologia , Peróxido de Hidrogênio/farmacologia , Relação Estrutura-Atividade , Histona Desacetilases/metabolismo , Antineoplásicos/farmacologia , Histona Desacetilase 1/farmacologia , Proliferação de Células
6.
BMC Palliat Care ; 22(1): 138, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715158

RESUMO

BACKGROUND: Previous studies of do-not-resuscitate (DNR) or do-not-intubate (DNI) orders in stroke patients have primarily been conducted in North America or Europe. However, characteristics associated with DNR/DNI orders in stroke patients in Asia have not been reported. METHODS: Based on the Taiwan Stroke Registry, this nationwide cross-sectional study enrolled hospitalized stroke patients from 64 hospitals between 2006 and 2020. We identified characteristics associated with DNR/DNI orders using a two-level random effects model. RESULTS: Among the 114,825 patients, 5531 (4.82%) had DNR/DNI orders. Patients with acute ischemic stroke (AIS) had the highest likelihood of having DNR/DNI orders (adjusted odds ratio [aOR] 1.76, 95% confidence interval [CI] 1.61-1.93), followed by patients with intracerebral hemorrhage (ICH), and patients with subarachnoid hemorrhage (SAH) had the lowest likelihood (aOR 0.53, 95% CI 0.43-0.66). From 2006 to 2020, DNR/DNI orders increased in all three types of stroke. In patients with AIS, women were significantly more likely to have DNR/DNI orders (aOR 1.23, 95% CI 1.15-1.32), while patients who received intravenous alteplase had a lower likelihood (aOR 0.74, 95% CI 0.65-0.84). Patients with AIS who were cared for by religious hospitals (aOR 0.55, 95% CI 0.35-0.87) and patients with SAH who were cared for by medical centers (aOR 0.40, 95% CI 0.17-0.96) were significantly less likely to have DNR/DNI orders. CONCLUSIONS: In Taiwan, DNR/DNI orders increased in stroke patients between 2006 and 2020. Hospital characteristics were found to play a significant role in the use of DNR/DNI orders.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Taiwan/epidemiologia , Estudos Transversais , Ordens quanto à Conduta (Ética Médica) , Sistema de Registros , Hospitais
7.
Acta Cardiol Sin ; 39(5): 755-764, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37720404

RESUMO

Background: Previous studies have reported that statins have inconsistent and marginal cardiovascular (CV) benefits in patients with end-stage renal disease (ESRD). However, whether statins play a secondary preventive role in patients with peripheral artery disease (PAD) and ESRD remains unclear. Objectives: This study aimed to compare the long-term clinical outcomes between statin users and nonusers with PAD and ESRD. Methods: This retrospective cohort study assessed the long-term protective effects of statins using data from the National Health Insurance Research Database in Taiwan. Propensity score matching was performed according to sex, age, index year, related comorbidities, and medications. The main outcomes were limb events and major adverse CV events (MACEs). Results: The statin user group (n = 4,460) was compared with the propensity score-matched statin nonuser group (n = 4,460). The mean age of the matched patients was 64 years, and 40% of the patients were men. The baseline characteristics of the groups were well-balanced. The overall limb event and MACE rates were not different between the two groups. However, the statin user group had lower rates of limb amputation [adjusted hazard ratio (aHR): 0.85, 95% confidence interval (CI): 0.73-0.99], stroke (aHR: 0.71, 95% CI: 0.62-0.83), CV death (aHR: 0.46, 95% CI: 0.32-0.66), and all-cause death (aHR: 0.45, 95% CI: 0.42-0.48) despite having a higher rate of percutaneous transluminal angioplasty for PAD. Conclusions: This population-based retrospective cohort study demonstrated that statin therapy was associated with a lower risk of limb amputation, nonfatal stroke, CV death, and all-cause death in patients with PAD and ESRD.

8.
Bioorg Chem ; 121: 105675, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35182882

RESUMO

Fms-like tyrosine kinase 3 (FLT3) is considered a promising therapeutic target for acute myeloid leukemia (AML) in the clinical. However, monotherapy with FLT3 inhibitor is usually accompanied by drug resistance. Dual inhibitors might be therapeutically beneficial to patients with AML due to their ability to overcome drug resistance. Mitogen-activated protein kinase (MAPK)-interacting kinases (MNKs) phosphorylate eukaryotic translation initiation factor 4E (eIF4E), which brings together the RAS/RAF/ERK and PI3K/AKT/mTOR oncogenic pathways. Therefore, dual inhibition of FLT3 and MNK2 might have an additive effect against AML. Herein, a structure-based virtual screening approach was performed to identify dual inhibitors of FLT3 and MNK2 from the ChemDiv database. Compound K783-0308 was identified as a dual inhibitor of FLT3 and MNK2 with IC50 values of 680 and 406 nM, respectively. In addition, the compound showed selectivity for both FLT3 and MNK2 in a panel of 82 kinases. The structure-activity relationship analysis and common interactions revealed interactions between K783-0308 analogs and FLT3 and MNK2. Furthermore, K783-0308 inhibited MV-4-11 and MOLM-13 AML cell growth and induced G0/G1 cell cycle arrest. Taken together, the dual inhibitor K783-0308 showed promising results and can be potentially optimized as a lead compound for AML treatment.


Assuntos
Leucemia Mieloide Aguda , Tirosina Quinase 3 Semelhante a fms , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação , Fosfatidilinositol 3-Quinases , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Serina-Treonina Quinases
9.
J Enzyme Inhib Med Chem ; 37(1): 226-235, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34894949

RESUMO

Bruton tyrosine kinase (BTK) is linked to multiple signalling pathways that regulate cellular survival, activation, and proliferation. A covalent BTK inhibitor has shown favourable outcomes for treating B cell malignant leukaemia. However, covalent inhibitors require a high reactive warhead that may contribute to unexpected toxicity, poor selectivity, or reduced effectiveness in solid tumours. Herein, we report the identification of a novel noncovalent BTK inhibitor. The binding interactions (i.e. interactions from known BTK inhibitors) for the BTK binding site were identified and incorporated into a structure-based virtual screening (SBVS). Top-rank compounds were selected and testing revealed a BTK inhibitor with >50% inhibition at 10 µM concentration. Examining analogues revealed further BTK inhibitors. When tested across solid tumour cell lines, one inhibitor showed favourable inhibitory activity, suggesting its potential for targeting BTK malignant tumours. This inhibitor could serve as a basis for developing an effective BTK inhibitor targeting solid cancers.


Assuntos
Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Tirosina Quinase da Agamaglobulinemia/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade
10.
J Biol Chem ; 295(11): 3734-3745, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32005667

RESUMO

Most of Gram-positive bacteria anchor surface proteins to the peptidoglycan cell wall by sortase, a cysteine transpeptidase that targets proteins displaying a cell wall sorting signal. Unlike other bacteria, Clostridium difficile, the major human pathogen responsible for antibiotic-associated diarrhea, has only a single functional sortase (SrtB). Sortase's vital importance in bacterial virulence has been long recognized, and C. difficile sortase B (Cd-SrtB) has become an attractive therapeutic target for managing C. difficile infection. A better understanding of the molecular activity of Cd-SrtB may help spur the development of effective agents against C. difficile infection. In this study, using site-directed mutagenesis, biochemical and biophysical tools, LC-MS/MS, and crystallographic analyses, we identified key residues essential for Cd-SrtB catalysis and substrate recognition. To the best of our knowledge, we report the first evidence that a conserved serine residue near the active site participates in the catalytic activity of Cd-SrtB and also SrtB from Staphylococcus aureus The serine residue indispensable for SrtB activity may be involved in stabilizing a thioacyl-enzyme intermediate because it is neither a nucleophilic residue nor a substrate-interacting residue, based on the LC-MS/MS data and available structural models of SrtB-substrate complexes. Furthermore, we also demonstrated that residues 163-168 located on the ß6/ß7 loop of Cd-SrtB dominate specific recognition of the peptide substrate PPKTG. The results of this work reveal key residues with roles in catalysis and substrate specificity of Cd-SrtB.


Assuntos
Aminoácidos/metabolismo , Aminoaciltransferases/química , Aminoaciltransferases/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biocatálise , Clostridioides difficile/enzimologia , Cisteína Endopeptidases/química , Cisteína Endopeptidases/metabolismo , Sequência de Aminoácidos , Aminoaciltransferases/genética , Proteínas de Bactérias/genética , Sequência Conservada , Cristalografia por Raios X , Cisteína Endopeptidases/genética , Mutação/genética , Estrutura Secundária de Proteína , Serina/metabolismo , Relação Estrutura-Atividade , Especificidade por Substrato
11.
J Nat Prod ; 84(4): 1096-1103, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33600175

RESUMO

Type 2 diabetes mellitus (T2DM) is associated with pancreatic ß-cell dysfunction and insulin resistance. Islet amyloid polypeptide (IAPP) aggregation is found to induce islet ß-cell death in T2DM patients. Recently, we demonstrated that yakuchinone B derivative 1 exhibited inhibitory activity against IAPP aggregation. Thus, in this study, a series of synthesized yakuchinone B-inspired compounds were tested for their anti-IAPP aggregation activity. Four of these compounds, 4e-h, showed greater activity than the lead compound 1, in the sub-µM range (IC50 = 0.7-0.8 µM). The molecular docking analysis revealed crucial hydrogen bonds between the compounds and residues S19 and N22 and important hydrophobic interactions with residue I26. Notably, compounds 4g and 4h significantly protected ß-cells against IAPP-induced toxicity with EC50 values of 0.1 and 0.2 µM, respectively. In contrast, the protective activities of compounds 4e and 4f were weak. Overall, these results suggest that the compounds exhibiting IAPP aggregation-inhibiting activity have the potential to treat T2DM.


Assuntos
Diarileptanoides/síntese química , Polipeptídeo Amiloide das Ilhotas Pancreáticas/antagonistas & inibidores , Animais , Linhagem Celular , Resistência à Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Simulação de Acoplamento Molecular , Agregação Patológica de Proteínas/tratamento farmacológico , Ratos
12.
J Nat Prod ; 84(1): 1-10, 2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33393294

RESUMO

Acute myeloid leukemia (AML) is an aggressive disease with a poor prognosis and a high degree of relapse seen in patients. Overexpression of FMS-like tyrosine kinase 3 (FLT3) is associated with up to 70% of AML patients. Wild-type FLT3 induces proliferation and inhibits apoptosis in AML cells, while uncontrolled proliferation of FLT3 kinase activity is also associated with FLT3 mutations. Therefore, inhibiting FLT3 activity is a promising AML therapy. Flavonoids are a group of phytochemicals that can target protein kinases, suggesting their potential antitumor activities. In this study, several plant-derived flavonoids have been identified with FLT3 inhibitory activity. Among these compounds, compound 40 (5,7,4'-trihydroxy-6-methoxyflavone) exhibited the most potent inhibition against not only FLT3 (IC50 = 0.44 µM) but also FLT3-D835Y and FLT3-ITD mutants (IC50 = 0.23 and 0.39 µM, respectively). The critical interactions between the FLT3 binding site and the compounds were identified by performing a structure-activity relationship analysis. Furthermore, the results of cellular assays revealed that compounds 28, 31, 32, and 40 exhibited significant cytotoxicity against two human AML cell lines (MOLM-13 and MV-4-11), and compounds 31, 32, and 40 resulted in cell apoptosis and G0/G1 cell cycle arrest. Collectively, these flavonoids have the potential to be further optimized as FLT3 inhibitors and provide valuable chemical information for the development of new AML drugs.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Flavonoides/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/uso terapêutico , Antineoplásicos/química , Humanos , Leucemia Mieloide Aguda/genética , Inibidores de Proteínas Quinases/química , Ensaios Antitumorais Modelo de Xenoenxerto , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/química , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/farmacologia
13.
J Enzyme Inhib Med Chem ; 36(1): 98-108, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33167727

RESUMO

The STE20 kinase family is a complex signalling cascade that regulates cytoskeletal organisation and modulates the stress response. This signalling cascade includes various kinase mediators, such as TAOK1 and MAP4K5. The dysregulation of the STE20 kinase pathway is linked with cancer malignancy. A small-molecule inhibitor targeting the STE20 kinase pathway has therapeutic potential. In this study, a structure-based virtual screening (SBVS) approach was used to identify potential dual TAOK1 and MAP4K5 inhibitors. Enzymatic assays confirmed three potential dual inhibitors (>50% inhibition) from our virtual screening, and analysis of the TAOK1 and MAP4K5 binding sites indicated common interactions for dual inhibition. Compound 1 revealed potent inhibition of colorectal and lung cancer cell lines. Furthermore, compound 1 arrested cancer cells in the G0/G1 phase, which suggests the induction of apoptosis. Altogether, we show that the STE20 signalling mediators TAOK1 and MAP4K5 are promising targets for drug research.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Int J Mol Sci ; 22(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34299072

RESUMO

Five new compounds, eupatodibenzofuran A (1), eupatodibenzofuran B (2), 6-acetyl-8-methoxy-2,2-dimethylchroman-4-one (3), eupatofortunone (4), and eupatodithiecine (5), have been isolated from the aerial part of Eupatorium fortunei, together with 11 known compounds (6‒16). Compounds 1 and 2 featured a new carbon skeleton with an unprecedented 1-(9-(4-methylphenyl)-6-methyldibe nzo[b,d]furan-2-yl)ethenone. Among the isolates, compound 1 exhibited potent inhibitory activity with IC50 values of 5.95 ± 0.89 and 5.55 ± 0.23 µM, respectively, against A549 and MCF-7 cells. The colony-formation assay demonstrated that compound 1 (5 µM) obviously decreased A549 and MCF-7 cell proliferation, and Western blot test confirmed that compound 1 markedly induced apoptosis of A549 and MCF-7 cells through mitochondrial- and caspase-3-dependent pathways.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Eupatorium/química , Neoplasias/tratamento farmacológico , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/farmacologia , Acetofenonas/química , Antineoplásicos Fitogênicos/química , Apoptose , Benzofuranos/química , Proliferação de Células , Cromonas/química , Humanos , Estrutura Molecular , Neoplasias/patologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
Molecules ; 26(22)2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34834129

RESUMO

Xestoquinone is a polycyclic quinone-type metabolite with a reported antitumor effect. We tested the cytotoxic activity of xestoquinone on a series of hematological cancer cell lines. The antileukemic effect of xestoquinone was evaluated in vitro and in vivo. This marine metabolite suppressed the proliferation of Molt-4, K562, and Sup-T1 cells with IC50 values of 2.95 ± 0.21, 6.22 ± 0.21, and 8.58 ± 0.60 µM, respectively, as demonstrated by MTT assay. In the cell-free system, it inhibited the activity of topoisomerase I (Topo I) and II (Topo II) by 50% after treatment with 0.235 and 0.094 µM, respectively. The flow cytometric analysis indicated that the cytotoxic effect of xestoquinone was mediated through the induction of multiple apoptotic pathways in Molt-4 cells. The pretreatment of Molt-4 cells with N-acetyl cysteine (NAC) diminished the disruption of the mitochondrial membrane potential (MMP) and apoptosis, as well as retaining the expression of both Topo I and II. In the nude mice xenograft model, the administration of xestoquinone (1 µg/g) significantly attenuated tumor growth by 31.2% compared with the solvent control. Molecular docking, Western blotting, and thermal shift assay verified the catalytic inhibitory activity of xestoquinone by high binding affinity to HSP-90 and Topo I/II. Our findings indicated that xestoquinone targeted leukemia cancer cells through multiple pathways, suggesting its potential application as an antileukemic drug lead.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Choque Térmico HSP90/metabolismo , Quinonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
J Nat Prod ; 83(10): 2967-2975, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33026809

RESUMO

Excessive eIF4E phosphorylation by mitogen-activated protein kinase (MAPK)-interacting kinases 1 and 2 (MNK1 and MNK2; collectively, MNKs) has been associated with oncogenesis. The overexpression of eIF4E in acute myeloid leukemia (AML) is related to cancer cell growth and survival. Thus, the inhibition of MNKs and eIF4E phosphorylation are potential therapeutic strategies for AML. Herein, a structure-based virtual screening approach was performed to identify potential MNK inhibitors from natural products. Three flavonoids, apigenin, hispidulin, and luteolin, showed MNK2 inhibitory activity with IC50 values of 308, 252, and 579 nM, respectively. A structure-activity relationship analysis was performed to disclose the molecular interactions. Furthermore, luteolin exhibited substantial inhibitory efficacy against MNK1 (IC50 = 179 nM). Experimental results from cellular assays showed that hispidulin and luteolin inhibited the growth of MOLM-13 and MV4-11 AML cells by downregulating eIF4E phosphorylation and arresting the cell cycle at the G0/G1 phase. Therefore, hispidulin and luteolin showed promising results as lead compounds for the potential treatment for AML.


Assuntos
Flavonoides , Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide Aguda , Proteínas Serina-Treonina Quinases , Ciclo Celular , Linhagem Celular Tumoral , Humanos , Estrutura Molecular , Fosforilação , Inibidores de Proteínas Quinases , Relação Estrutura-Atividade
17.
Bioorg Chem ; 98: 103729, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32179284

RESUMO

Leucettamine B is a natural product found in marine sponge Leucetta microraphis. Several of analogs of its family, such as aplysinopsine and clathridine, are medicinally active molecules which have applications in many pharmaceuticals and healthcare products; however, thus far, leucettamine B has not been studied. In this report, we describe the synthesis of a new class of analogs of leucettamine B obtained by Knoevenagel condensation using a microwave reactor. The 25 newly synthesized compounds were tested against MDA-MB-468, SW480, and Mahlavu cell lines for anticancer activity. Among them, the carborane-based compound (Z)-5-(benzo[d][1,3]dioxol-5-ylmethylene)-3-(1-closo-carboranyl)-2-thioxo -thiazolidin-4-one (49) and (Z)-5-(benzo[d][1,3]dioxol-5-ylmethylene)-3-(2-(pyrrolidin-1-yl)ethyl)-2-thioxothiazolidin-4-one (31) derivatives were found to have the most potential for use against tumor cells. The carborane derivative 49 had the lowest IC50 value against the SW480 cell line (4.7 µM) and the Mahlavu (6.6 µM) cell line. Furthermore, compound 31 also had a low IC50 value against SW480 (7.5 µM). Our research shows that leucettamine B analogs might have potential for use in cancer chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Boranos/farmacologia , Desenho de Fármacos , Imidazóis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Boranos/síntese química , Boranos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Imidazóis/síntese química , Imidazóis/química , Estrutura Molecular , Relação Estrutura-Atividade , Células Vero
18.
Mar Drugs ; 18(8)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32718084

RESUMO

13-Acetoxysarcocrassolide (13-AC), a marine cytotoxic product isolated from the alcyonacean coral Lobophytum crassum, exhibited potent antitumor and immunostimulant effects as reported in previous studies. However, the 13-AC antitumor mechanism of action against oral cancer cells remains unclear. The activity of 13-AC against Ca9-22 cancer cells was determined using MTT assay, flow cytometric analysis, immunofluorescence, immunoprecipitation, Western blotting, and siRNA. 13-AC induced apoptosis in oral cancer cells Ca9-22 through the disruption of mitochondrial membrane potential (MMP) and the stimulation of reactive oxygen species (ROS) generation. It increased the expression of apoptosis- and DNA damage-related proteins in a concentration- and time-dependent manner. It exerted potent antitumor effect against oral cancer cells, as demonstrated by the in vivo xenograft animal model. It significantly reduced the tumor volume (55.29%) and tumor weight (90.33%). The pretreatment of Ca9-22 cells with N-acetylcysteine (NAC) inhibited ROS production resulting in the attenuation of the cytotoxic activity of 13-AC. The induction of the Keap1-Nrf2 pathway and the promotion of p62/SQSTM1 were observed in Ca9-22 cells treated with 13-AC. The knockdown of p62 expression by siRNA transfection significantly attenuated the effect of 13-AC on the inhibition of cell viability. Our results indicate that 13-AC exerted its cytotoxic activity through the promotion of ROS generation and the suppression of the antioxidant enzyme activity. The apoptotic effect of 13-AC was found to be mediated through the interruption of the Keap1/Nrf2/p62/SQSTM1 pathway, suggesting its potential future application as an anticancer agent.


Assuntos
Antineoplásicos/farmacologia , Diterpenos/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Bucais/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Proteína Sequestossoma-1/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células HCT116 , Células HeLa , Humanos , Células MCF-7 , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Nus , Neoplasias Bucais/enzimologia , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Espécies Reativas de Oxigênio/metabolismo , Proteína Sequestossoma-1/genética , Transdução de Sinais , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Molecules ; 25(23)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266202

RESUMO

Alzheimer's disease (AD), which is among the most prevalent neurodegenerative diseases, manifests as increasing memory loss and cognitive decline. Tau phosphorylation and aggregation are strongly linked to neurodegeneration, as well as associated with chronic neuroinflammatory processes. The anti-inflammation effects of natural products have led to wide recognition of their potential for use in treating and preventing AD. This study investigated whether eupatin, a polymethoxyflavonoid found in Artemisia species, has inhibitory effects on neuroinflammation and tau phosphorylation. We treated mouse macrophages and microglia cells with lipopolysaccharides (LPSs) to activate inflammatory signals, and we treated neuronal cells with a protein phosphatase 2A inhibitor, okadaic acid (OA), or transfection with pRK5-EGFP-Tau P301L plasmid to induce tau phosphorylation. The results indicated that eupatin significantly reduced the LPS-induced protein expression and phosphorylation of p65 and inducible nitric oxide synthase as well as downstream products interleukin 6 and nitrite, respectively. Furthermore, eupatin markedly inhibited the expression of phospho-tau in response to OA treatment and plasmid transfection. We discovered that this inhibition was achieved through the inhibition of glycogen synthase kinase 3ß (GSK3ß), and molecular docking results suggested that eupatin can sufficiently bind to the GSK3ß active site. Our results demonstrate that eupatin has neuroprotective effects, making it suitable for AD treatment.


Assuntos
Anti-Inflamatórios/farmacologia , Flavonoides/farmacologia , Macrófagos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais/farmacologia , Proteínas tau/antagonistas & inibidores , Animais , Apoptose , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Microglia/metabolismo , Microglia/patologia , Simulação de Acoplamento Molecular , Fosforilação , Fitoterapia , Zingiberaceae/química
20.
IUBMB Life ; 71(5): 539-548, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30578665

RESUMO

For many, "DNA mimic protein" (DMP) remains an unfamiliar term. The key feature of these proteins is their DNA-like shape and charge distribution, and they affect the activity of DNA-binding proteins by occupying their DNA-binding domains. Functionally, DMPs regulate mechanisms such as gene expression, restriction, and DNA repair as well as the nucleosome package. Although a few DMPs, such as phage uracil DNA glycosylase inhibitor (UGI) and overcome classical restriction (Ocr), were reported about 20 years ago, only a small number of DMPs have been studied to date. In 2014, we reviewed the functional and structural features of 16 DMPs that were known at the time. Now, seven new DMPs, namely anti-CRISPR suppressors AcrF2, AcrF10 and AcrIIA4, human immunodeficiency virus essential factor VPR, multi-functional inhibitor anti-restriction nuclease (Arn), translational regulator AbbA, and putative Z-DNA mimic MBD3, have been reported. In addition, further study of two previously known DMPs, DMP19 and SAUGI, increased our knowledge of their importance and function. Here, we discuss these updated results and address how several characteristics of the structure/sequence of DMPs (e.g. the DNA-like charge distribution and structural D/E-rich repeats) might someday be used to identify new DMPs using bioinformatic approach. © 2018 IUBMB Life, 71(5):539-548, 2019.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , DNA/química , Mimetismo Molecular , Humanos , Modelos Moleculares
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