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1.
Angew Chem Int Ed Engl ; : e202407898, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739536

RESUMO

The quest for smart electronics with higher energy densities has intensified the development of high-voltage LiCoO2 (LCO). Despite their potential, LCO materials operating at 4.7 V faces critical challenges, including interface degradation and structural collapse. Herein, we propose a collective surface architecture through precise nanofilm coating and doping that combines an ultra-thin LiAlO2 coating layer and gradient doping of Al. This architecture not only mitigates side reactions, but also improves the Li+ migration kinetics on the LCO surface. Meanwhile, gradient doping of Al inhibited the severe lattice distortion caused by the irreversible phase transition of O3-H1-3-O1, thereby enhanced the electrochemical stability of LCO during 4.7 V cycling. DFT calculations further revealed that our approach significantly boosts the electronic conductivity. As a result, the modified LCO exhibited an outstanding reversible capacity of 230 mAh g-1 at 4.7 V, which is approximately 28 % higher than the conventional capacity at 4.5 V. To demonstrate their practical application, our cathode structure shows improved stability in full pouch cell configuration under high operating voltage. LCO exhibited an excellent cycling stability, retaining 82.33 % after 1000 cycles at 4.5 V. This multifunctional surface modification strategy offers a viable pathway for the practical application of LCO materials, setting a new standard for the development of high-energy-density and long-lasting electrode materials.

2.
Int J Cancer ; 145(3): 714-727, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30675909

RESUMO

PARP1 inhibitors (PARPis) are used clinically during cancer therapy and are thought to exert their cytotoxicity through PARP1 polymerase inhibition and PARP1-DNA trapping. Here, we showed no significant correlation between PARP1-DNA trapping and cytotoxicity induced by PARPis. We complemented PARP1-knockout sublines with wild-type PARP1 and 11 mutants with different point mutations that affect the polymerase activity. When examining the PARPi talazoparib, the induced cytotoxicity was highly significantly correlated with cellular PARP1 polymerase activity, but not with its PARP1-DNA trapping or polymerase inhibition. Similarly, talazoparib's PARP1-DNA trapping revealed significant correlation with the polymerase activity rather than its inhibition. Differently, however, when evaluating purified wild-type and mutated PARP1, we identified an almost linear relationship between PARPis' inhibiting PARP1 dissociation from DNA and their cytotoxicity in 17 cancer cell lines. In contrast, no significant correlation existed between PARP1 polymerase inhibition in the histone-based systems and the cytotoxicity. After careful comparisons on different methods and detection targets, we conclude that the PARPi-mediated increase in PARP1-DNA binding by inhibiting autoPARylation of PARP1 on DNA rather than in PARP1-DNA trapping is correlated with PARPi's cytotoxicity. Accordingly, we established a new PARPi screening model that more closely predicts cytotoxicity.


Assuntos
DNA de Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Linhagem Celular Tumoral , DNA de Neoplasias/genética , Ensaios de Seleção de Medicamentos Antitumorais , Técnicas de Silenciamento de Genes , Humanos , NAD/metabolismo , Neoplasias/genética , Ftalazinas/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genética
3.
Cancer Sci ; 109(3): 821-831, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29274141

RESUMO

With increasing uses of poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) for cancer therapy, understanding their resistance is becoming urgent. However, acquired PARPi resistance in the phosphatase and tensin homolog (PTEN)-deficient background is poorly understood. We generated 3 PARPi-resistant PTEN-deficient glioblastoma U251 variants separately with olaparib (U251/OP), talazoparib (U251/TP) and simmiparib (U251/SP). These variants displayed consistent resistance (2.46-71.78-fold) to all 5 PARPi, including niraparib and rucaparib, and showed higher degrees of resistance to the PARPi to which the parental cells were more sensitive. The resistance was characteristic of fast emergence and high stability. However, the resistance acquirement did not cause an increasingly aggressive phenotype. The resistance was not correlated to various factors, including PTEN mutations. The PARPi-treated variants produced less γH2AX and G2/M arrest. Consistently, loss of 53BP1 occurred in all variants and its compensation enhanced their sensitivity to PARPi by approximately 76%. The variants revealed slightly different cross-resistance profiles to 13 non-PARPi anticancer drugs. All were resistant to Ara-C (6-8-fold) but showed differential resistance to 5-fluorouracil, gemcitabine and paclitaxel. Almost no resistance was observed to the rest drugs, including cisplatin. SAMHD1 was overexpressed in all the variants and its knockout completely restored their sensitivity to Ara-C but did not affect their PARPi sensitivity. The present study demonstrates a consistent resistance profile to PARPi and a unique cross-resistance profile to non-PARPi drugs in different PARPi-resistant U251 cells and reveals 53BP1 loss and SAMHD1 overexpression as the primary mechanisms responsible for their resistance to PARPi and Ara-C, respectively. These effects probably result from heritable gene change(s) caused by persistent PARPi exposure.


Assuntos
Antineoplásicos/farmacologia , Citarabina/farmacologia , Glioblastoma/genética , PTEN Fosfo-Hidrolase/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Proteína 1 com Domínio SAM e Domínio HD/genética , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Humanos , PTEN Fosfo-Hidrolase/deficiência , Ftalazinas/farmacologia , Piperazinas/farmacologia
4.
Bioorg Med Chem Lett ; 27(5): 1316-1318, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28162858

RESUMO

It is demonstrated that natural product vindoline can enhance the glucose-stimulated insulin secretion (GSIS) in MIN6 cells with the EC50 value of 50.2µM. In order to improve the activities, a series of vindoline derivatives are synthesized and evaluated in MIN6 cells. Compounds 4, 8, 17 and 24 show about 4.5 times more effective stimulation insulin secretion ability (EC50: 10.4, 14.2, 11.0 and 12.7µM, respectively) than vindoline.


Assuntos
Glucose , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/metabolismo , Vimblastina/análogos & derivados , Animais , Linhagem Celular , Hipoglicemiantes/síntese química , Hipoglicemiantes/farmacologia , Concentração Inibidora 50 , Secreção de Insulina , Camundongos , Estrutura Molecular , Vimblastina/síntese química , Vimblastina/química , Vimblastina/farmacologia
5.
Front Pharmacol ; 15: 1392729, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38895620

RESUMO

Background: Oligomeric amyloid beta (oAß) is a toxic factor that acts in the early stage of Alzheimer's disease (AD) and may initiate the pathologic cascade. Therefore, detecting oAß has a crucial role in the early diagnosis, monitoring, and treatment of AD. Purpose: The purpose of this study was to evaluate MRI signal changes in different mouse models and the time-dependent signal changes using our novel gadolinium (Gd)-dodecane tetraacetic acid (DOTA)- ob5 aptamer contrast agent. Methods: We developed an MRI contrast agent by conjugating Gd-DOTA-DNA aptamer called ob5 to evaluate its ability to detect oAß deposits in the brain using MRI. A total of 10 control mice, 9 3xTg AD mice, and 11 APP/PS/Tau AD mice were included in this study, with the age of each model being 16 or 36 weeks. A T1-weighted image was acquired at the time points before (0 min) and after injection of the contrast agent at 5, 10, 15, 20, and 25 min. The analyses were performed to compare MRI signal differences among the three groups and the time-dependent signal differences in different mouse models. Results: Both 3xTg AD and APP/PS/Tau AD mouse models had higher signal enhancement than control mice at all scan-time points after injection of our contrast media, especially in bilateral hippocampal areas. In particular, all Tg AD mouse models aged 16 weeks showed a higher contrast enhancement than those aged 36 weeks. For 3xTg AD and APP/PS/Tau AD groups, the signal enhancement was significantly different among the five time points (0 min, 5 min, 10 min, 15 min, 20 min, and 25 min) in multiple ROI areas, typically in the bilateral hippocampus, left thalamus, and left amygdala. Conclusion: The findings of this study suggest that the expression of the contrast agent in different AD models demonstrates its translational flexibility across different species. The signal enhancement peaked around 15-20 min after injection of the contrast agent. Therefore, our novel contrast agent targeting oAß has the potential ability to diagnose early AD and monitor the progression of AD.

6.
Brain Behav ; 14(1): e3381, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38376028

RESUMO

BACKGROUND: Apolipoprotein E (ApoE) ε4 carriers have a higher risk of developing Alzheimer's disease (AD) and show brain atrophy and cognitive decline even before diagnosis. OBJECTIVE: To predict ApoE ε4 status using gray matter volume (GMV) obtained from magnetic resonance imaging images and demographic data with machine learning (ML) methods. METHODS: We recruited 74 participants (25 probable AD, 24 amnestic mild cognitive impairment, and 25 cognitively normal older people) with known ApoE genotype (22 ApoE ε4 carriers and 52 noncarriers) and scanned them with three-dimensional (3D) T1-weighted (T1W) and 3D double inversion recovery (DIR) sequences. We extracted GMV from regions of interest related to AD pathology and used them as features along with age and mini-mental state examination (MMSE) scores to train different ML models. We performed both receiver operating characteristic curve analysis and the prediction analysis of the ApoE ε4 carrier with different ML models. RESULTS: The best model of ML analyses was a cubic support vector machine (SVM3) that used age, the MMSE score, and DIR GMVs at the amygdala, hippocampus, and precuneus as features (AUC = .88). This model outperformed models using T1W GMV or demographic data alone. CONCLUSION: Our results suggest that brain atrophy with DIR GMV and cognitive decline with aging can be useful biomarkers for predicting ApoE ε4 status and identifying individuals at risk of AD progression.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Idoso , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Apolipoproteína E4/genética , Alelos , Apolipoproteínas E/genética , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/genética , Disfunção Cognitiva/patologia , Genótipo , Cognição , Imageamento por Ressonância Magnética/métodos , Atrofia/patologia
7.
Adv Sci (Weinh) ; : e2402380, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38837633

RESUMO

Simultaneously achieving high-energy-density and high-power-density is a crucial yet challenging objective in the pursuit of commercialized power batteries. In this study, atomic layer deposition (ALD) is employed combined with a coordinated thermal treatment strategy to construct a densely packed, electron-ion dual conductor (EIC) protective coating on the surface of commercial LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode material, further enhanced by gradient Al doping (Al@EIC-NCM523). The ultra-thin EIC effectively suppresses side reactions, thereby enhancing the stability of the cathode-electrolyte interphase (CEI) at high-voltages. The EIC's dual conduction capability provides a potent driving force for Li+ transport at the interface, promoting the formation of rapid ion deintercalation pathways within the Al@EIC-NCM523 bulk phase. Moreover, the strategic gradient doping of Al serves to anchor the atomic spacing of Ni and O within the structure of Al@EIC-NCM523, curbing irreversible phase transitions at high-voltages and preserving the integrity of its layered structure. Remarkably, Al@EIC-NCM523 displays an unprecedented rate capability (114.7 mAh g-1 at 20 C), and a sustained cycling performance (capacity retention of 74.72% after 800 cycles at 10 C) at 4.6 V. These findings demonstrate that the proposed EIC and doping strategy holds a significant promise for developing high-energy-density and high-power-density lithium-ion batteries (LIBs).

8.
Front Aging Neurosci ; 15: 1291376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38161586

RESUMO

Introduction: Alzheimer's disease (AD) presents typically gray matter atrophy and white matter abnormalities in neuroimaging, suggesting that the gray-white matter boundary could be altered in individuals with AD. The purpose of this study was to explore differences of gray-white matter boundary Z-score (gwBZ) and its tissue volume (gwBTV) between patients with AD, amnestic mild cognitive impairment (MCI), and cognitively normal (CN) elderly participants. Methods: Three-dimensional T1-weight images of a total of 227 participants were prospectively obtained from our institute from 2006 to 2022 to map gwBZ and gwBTV on images. Statistical analyses of gwBZ and gwBTV were performed to compare the three groups (AD, MCI, CN), to assess their correlations with age and Korean version of the Mini-Mental State Examination (K-MMSE), and to evaluate their effects on AD classification in the hippocampus. Results: This study included 62 CN participants (71.8 ± 4.8 years, 20 males, 42 females), 72 MCI participants (72.6 ± 5.1 years, 23 males, 49 females), and 93 AD participants (73.6 ± 7.7 years, 22 males, 71 females). The AD group had lower gwBZ and gwBTV than CN and MCI groups. K-MMSE showed positive correlations with gwBZ and gwBTV whereas age showed negative correlations with gwBZ and gwBTV. The combination of gwBZ or gwBTV with K-MMSE had a high accuracy in classifying AD from CN in the hippocampus with an area under curve (AUC) value of 0.972 for both. Conclusion: gwBZ and gwBTV were reduced in AD. They were correlated with cognitive function and age. Moreover, gwBZ or gwBTV combined with K-MMSE had a high accuracy in differentiating AD from CN in the hippocampus. These findings suggest that evaluating gwBZ and gwBTV in AD brain could be a useful tool for monitoring AD progression and diagnosis.

9.
Cell Death Dis ; 12(2): 183, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589588

RESUMO

Monotherapy with poly ADP-ribose polymerase (PARP) inhibitors results in a limited objective response rate (≤60% in most cases) in patients with homologous recombination repair (HRR)-deficient cancer, which suggests a high rate of resistance in this subset of patients to PARP inhibitors (PARPi). To overcome resistance to PARPi and to broaden their clinical use, we performed high-throughput screening of 99 anticancer drugs in combination with PARPi to identify potential therapeutic combinations. Here, we found that GSK3 inhibitors (GSK3i) exhibited a strong synergistic effect with PARPi in a panel of colorectal cancer (CRC) cell lines with diverse genetic backgrounds. The combination of GSK3ß and PARP inhibition causes replication stress and DNA double-strand breaks, resulting in increased anaphase bridges and abnormal spindles. Mechanistically, inhibition or genetic depletion of GSK3ß was found to impair the HRR of DNA and reduce the mRNA and protein level of BRCA1. Finally, we demonstrated that inhibition or depletion of GSK3ß could enhance the in vivo sensitivity to simmiparib without toxicity. Our results provide a mechanistic understanding of the combination of PARP and GSK3 inhibition, and support the clinical development of this combination therapy for CRC patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Sinergismo Farmacológico , Feminino , Glicogênio Sintase Quinase 3 beta/metabolismo , Células HCT116 , Células HT29 , Células HeLa , Recombinação Homóloga/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Distribuição Aleatória , Transfecção , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Cell Death Dis ; 11(1): 71, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992690

RESUMO

Poly(ADP-ribose) polymerase 1 (PARP1) regulates gene transcription in addition to functioning as a DNA repair factor. Forkhead box O1 (FoxO1) is a transcription factor involved in extensive biological processes. Here, we report that PARP1 binds to two separate motifs on the FoxO1 promoter and represses its transcription in a polymerase-independent manner. Using PARP1-knock out (KO) cells, wild-type-PARP1-complemented cells and catalytic mutant PARP1E988K-reconstituted cells, we investigated transcriptional regulation by PARP1. PARP1 loss led to reduced DNA damage response and ~362-fold resistance to five PARP inhibitors (PARPis) in Ewing sarcoma cells. RNA sequencing showed 492 differentially expressed genes in a PARP1-KO subline, in which the FoxO1 mRNA levels increased up to more than five times. The change in the FoxO1 expression was confirmed at both mRNA and protein levels in different PARP1-KO and complemented cells. Moreover, exogenous PARP1 overexpression reduced the endogenous FoxO1 protein in RD-ES cells. Competitive EMSA and ChIP assays revealed that PARP1 specifically bound to the FoxO1 promoter. DNase I footprinting, mutation analyses, and DNA pulldown FREP assays showed that PARP1 bound to two particular nucleotide sequences separately located at -813 to -826 bp and -1805 to -1828 bp regions on the FoxO1 promoter. Either the PARPi olaparib or the PARP1 catalytic mutation (E988K) did not impair the repression of PARP1 on the FoxO1 expression. Exogenous FoxO1 overexpression did not impair cellular PARPi sensitivity. These findings demonstrate a new PARP1-gene promoter binding mode and a new transcriptional FoxO1 gene repressor.


Assuntos
Proteína Forkhead Box O1/genética , Regulação da Expressão Gênica/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Sarcoma de Ewing/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Dano ao DNA/efeitos dos fármacos , Proteína Forkhead Box O1/metabolismo , Técnicas de Inativação de Genes , Humanos , Mutação , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Regiões Promotoras Genéticas , Ligação Proteica , Sarcoma de Ewing/genética , Regulação para Cima
11.
J Tradit Chin Med ; 36(4): 486-95, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-28459513

RESUMO

OBJECTIVE: To investigate the effects of Bazhen decoction (BZD), Siwu decoction (SWD) and Sijunzi decoction (SJZD) in mice with anemia induced by 5-fluorouracil (5-FU) and discussed the possible pharmacological hematopoietic mechanism to provide experimental evidence for the clinical use of the three classical prescriptions in the treatment of anemia. METHODS: Anemia was induced by intravenous injection of 5-FU and 80 female Kunming mice were randomly, assigned to oral administration of SWD, SJZD, or BZD daily for 10 days. Peripheral blood cells count and bone marrow cell cycle were monitored to evaluate anti-anemia effects. Serum cytokines, interferon-γ (IFN-γ), interleukin-3 (IL-3), erythropoietin (EPO), granulocyte-macrophage colony stimulating factor (GM-CSF), and tumor necrosis factor-α (TNF-α) were assayed. EPO mRNA expression was assayed in kidney and liver tissue homogenates. RESULTS: BZD and SWD significantly increased the number of red blood cells, hemoglobin concentration, and hematocrit, promoted bone marrow cells to enter the cell cycle, proliferate and differentiate, significantly increased IL-3 secretion, and significantly inhibited IFN-γ secretion. BZD stimulated transcription of EPO mRNA in the kidney and liver and enhanced serum EPO expression. A therapeutic effect of SJZD was not observed. CONCLUSION: BZD and SWD treatment specifically enhanced hematopoietic function and mediated myelopoiesis by altering serum cytokines levels and accelerating entry of bone marrow cells into the cell cycle. Better curative effects were achieved via nourishing both Qi and blood (BZD) than by enriching the blood (SWD) or invigorating Qi (SWZD) alone.


Assuntos
Anemia/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Anemia/induzido quimicamente , Anemia/genética , Anemia/metabolismo , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Ciclo Celular , Feminino , Fluoruracila/efeitos adversos , Humanos , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-3/genética , Interleucina-3/metabolismo , Camundongos , Resultado do Tratamento
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