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1.
Anal Chem ; 95(47): 17273-17283, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37955847

RESUMO

Graph neural networks (GNNs) have shown remarkable performance in predicting the retention time (RT) for small molecules. However, the training data set for a particular target chromatographic system tends to exhibit scarcity, which poses a challenge because the experimental process for measuring RT is costly. To address this challenge, transfer learning has been used to leverage an abundant training data set from a related source task. In this study, we present an improved transfer learning method to better predict the RT of molecules for a target chromatographic system by learning from a small training data set with a pretrained GNN. We use a graph isomorphism network as the architecture of the GNN. The GNN is pretrained on the METLIN-SMRT data set and is then fine-tuned on the target training data set for a fixed number of training iterations using the limited-memory Broyden-Fletcher-Goldfarb-Shanno optimizer with a learning rate decay. We demonstrate that the proposed method achieves superior predictive performance on various chromatographic systems compared with that of the existing transfer learning methods, especially when only a small training data set is available for use. A potential avenue for future research is to leverage multiple small training data sets from different chromatographic systems to further enhance the generalization performance.

2.
Phys Chem Chem Phys ; 24(43): 26870-26878, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36317530

RESUMO

Graph neural networks (GNNs) have been proven effective in the fast and accurate prediction of nuclear magnetic resonance (NMR) chemical shifts of a molecule. Existing methods, despite their effectiveness, suffer from high space complexity and are therefore limited to relatively small molecules. In this work, we propose a scalable GNN for NMR chemical shift prediction. To reduce the space complexity, we sparsify the graph representation of a molecule by regarding only heavy atoms as nodes and their chemical bonds as edges. To better learn from the sparsified graph representation, we improve the message passing and readout functions in the GNN. For the message passing function, we adapt the attention mechanism and residual connection to better capture local information around each node. For the readout function, we use both node-level and graph-level embeddings as the local and global information to better predict node-level chemical shifts. Through the experimental investigation using 13C and 1H NMR datasets, we demonstrate that the proposed method yields higher prediction accuracy and is more scalable to large molecules having many heavy atoms.


Assuntos
Imageamento por Ressonância Magnética , Redes Neurais de Computação , Espectroscopia de Ressonância Magnética
3.
Int J Mol Sci ; 18(2)2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28208647

RESUMO

Soy-leaf extracts exert their cardioprotective effects by inducing endothelium-dependent vasodilation in the arteries, and they favorably modulate the serum lipid profile. In this study, we investigated the atheroprotective effects of an ethanol extract of soy leaf (ESL) in human umbilical vein endothelial cells (HUVECs) and high-cholesterol diet (HCD)-fed low-density lipoprotein receptor deficient (LDLR-/-) mice. ESL induced the expression of Krüppel-like factor 2 (KLF2), an endothelial transcription factor, and endothelial nitric oxide synthase (eNOS), and suppressed the expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) through moderate inflammatory signal activation, not only in tumor necrosis factor-α (TNF-α)-stimulated HUVECs but also in 7-ketocholesterol (7-KC)-stimulated HUVECs. ESL supplementation reduced aortic lesion formation in Western diet-fed LDLR-/- mice by 46% (p < 0.01) compared to the HCD group. ESL also markedly decreased the aortic expression levels of VCAM-1, ICAM-1, monocyte chemotactic protein-1 (MCP-1), TNF-α, IL-6, IL-1ß, matrix metallopeptidase 9 (MMP-9), and fractalkine, while the expression of KLF2 was significantly increased. These results suggest that ESL supplementation has potential for preventing HCD-induced atherosclerosis effectively.


Assuntos
Moléculas de Adesão Celular/metabolismo , Glycine max/química , Fatores de Transcrição Kruppel-Like/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/química , Substâncias Protetoras/farmacologia , Animais , Aorta/metabolismo , Aorta/patologia , Aterosclerose/etiologia , Aterosclerose/metabolismo , Aterosclerose/patologia , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/genética , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Fatores de Transcrição Kruppel-Like/genética , Masculino , Camundongos , Camundongos Knockout , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Receptores de LDL/deficiência , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
4.
Drug Chem Toxicol ; 39(1): 111-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26045230

RESUMO

Three chemotoxins including dimethylnitrosamine (DMN), carbon tetrachloride (CCl4), and thioacetamide (TAA) are commonly used in hepatofibrotic models. We aimed to draw characteristics of histopathology and pro-fibrogenic cytokines including TGF-ß, PDGF and CTGF among three models. Rats were divided into six groups and intra-peritoneally injected with DMN (10 mg/kg, for three weeks, three consecutive days weekly), CCl4 (1.6 g/kg, for 10 weeks, twice weekly), TAA (200 mg/kg, for 12 weeks, twice weekly) or their corresponded treatment for each control group. The liver weights were decreased in DMN model, but not other models. Ascites were occurred as 3-, 2-, and 7-rats in DMN, CCl4, and TAA model, respectively. The lipid peroxidation was highest in CCl4 model, serum levels of liver enzymes were increased as similar severity. The hepatofibrotic alterations were remarkable in DMN and TAA model, but not CCl4 as evidenced by the Masson trichrome staining and hydroxyproline. The immunohistochemistry for α-SAM showed that the DMN model was most severely enhanced than other models. On the other hand, hepatic tissue levels of pro-fibrogenic cytokines including TGF-ß, PDGF, and CTGF were generally increased in three models, but totally different among models or measurement resources. Especially, serum levels of three cytokines were remarkably increased by CCl4 injection and CTGF levels in both hepatic tissue and serum were highest in CCl4 group. Our results firstly demonstrated comparative study for features of morphological finding and pro-fibrogenic cytokines in serum and hepatic protein levels among three models. Above results would be a helpful reference for hepatofibrotic studies.


Assuntos
Tetracloreto de Carbono/toxicidade , Dimetilnitrosamina/toxicidade , Cirrose Hepática Experimental/fisiopatologia , Tioacetamida/toxicidade , Animais , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Modelos Animais de Doenças , Imuno-Histoquímica , Peroxidação de Lipídeos/efeitos dos fármacos , Cirrose Hepática Experimental/induzido quimicamente , Masculino , Fator de Crescimento Derivado de Plaquetas/metabolismo , Ratos , Ratos Sprague-Dawley , Fator de Crescimento Transformador beta/metabolismo
5.
Chron Respir Dis ; 11(3): 147-152, 2014 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-24906688

RESUMO

The Leicester Cough Questionnaire (LCQ) is a self-administered questionnaire developed in England and validated for reliability. We developed a Korean translation of this questionnaire by applying a sequential forward and backward translation approach. The purpose of this study is to validate the Korean version of the LCQ (LCQ-K) in Korean patients with chronic cough. A multicenter prospective study was undertaken with 100 chronic cough patients who consented to participate in the study. The LCQ-K includes eight physical items, seven psychological items, and four social items. Visual analog scale (VAS) of cough, Borg Cough Scale (BCS), and Short Form-36 (SF-36) were used as external comparators. Participants included 52 women and 48 men with ages ranging from 18 years to 69 years. The concurrent validity comparing LCQ-K to VAS, BCS, and SF-36 yielded statistically significant Pearson correlation coefficients. The LCQ-K showed good reliability in three domains, with Cronbach's α coefficients ranging from 0.84 to 0.87 (total: 0.91). Test-retest reliability was investigated with single measure intraclass correlation coefficients, which were found to be practically and statistically significant (p = 0.005). Responsiveness was validated by effective size ranging from 1.16 to 1.40 in each domain. LCQ-K is a reliable, valid, and responsive disease-specific questionnaire for assessing symptoms and quality of life of Korean patients with chronic cough.

6.
J Cheminform ; 16(1): 25, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38429787

RESUMO

Graph neural networks (GNNs) have proven to be effective in the prediction of chemical reaction yields. However, their performance tends to deteriorate when they are trained using an insufficient training dataset in terms of quantity or diversity. A promising solution to alleviate this issue is to pre-train a GNN on a large-scale molecular database. In this study, we investigate the effectiveness of GNN pre-training in chemical reaction yield prediction. We present a novel GNN pre-training method for performance improvement.Given a molecular database consisting of a large number of molecules, we calculate molecular descriptors for each molecule and reduce the dimensionality of these descriptors by applying principal component analysis. We define a pre-text task by assigning a vector of principal component scores as the pseudo-label to each molecule in the database. A GNN is then pre-trained to perform the pre-text task of predicting the pseudo-label for the input molecule. For chemical reaction yield prediction, a prediction model is initialized using the pre-trained GNN and then fine-tuned with the training dataset containing chemical reactions and their yields. We demonstrate the effectiveness of the proposed method through experimental evaluation on benchmark datasets.

7.
Sci Rep ; 14(1): 5953, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38467736

RESUMO

Removal of volatile organic compounds (VOCs) from the air has been an important issue in many industrial fields. Traditionally, the operation of VOCs removal systems has relied on fixed operating conditions determined by domain experts based on their expertise and intuition. In practice, this manual operation cannot respond immediately to changes in the system environment. To facilitate the autonomous operation of the system, the operating conditions should be optimized properly in real time to adapt to the changes in the system environment. Recently, optimization frameworks have been widely applied to real-world industrial systems across various domains using different approaches. The primary motivation for this study is the effective implementation of an optimization framework targeting a VOCs removal system. In this paper, we present a data-driven autonomous operation method for optimizing the operating conditions of a VOCs removal system to enhance the overall performance. An optimization problem is formulated with the decision variables denoting the parameters associated with the operating condition, the environmental variables representing the measurements for the system environment, the constraints specifying the control ranges of the parameters, and the objective function representing the system performance as determined by the operating conditions and environment. Using the previous operation data from the system, a neural network is trained to model the system performance as a function of the decision and environmental variables to approximate the objective function. For the current state of the system environment, the optimal operating condition is derived by solving the optimization problem. A case study of a targeted VOCs removal system demonstrates that the proposed method effectively optimizes the operating conditions for improved system performance without intervention from domain experts.

8.
ACS Nano ; 18(27): 17764-17773, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38935840

RESUMO

Vacuum deposition of perovskites is a promising method for scale-up fabrication and uniform film growth. However, improvements in the photovoltaic performance of perovskites are limited by the fabrication of perovskite films, which are not optimized for high device efficiency in the vacuum evaporation process. Herein, we fabricate CsPbI2Br perovskite with high crystallinity and larger grain size by controlling the deposition sequence between PbI2 and CsBr. The nucleation barrier for perovskite formation is significantly lowered by first evaporating CsBr and then PbI2 (CsBr-PbI2), followed by the sequential evaporation of multiple layers. The results show that the reduced Gibbs free energy of CsBr-PbI2, compared with that of PbI2-CsBr, accelerates perovskite formation, resulting in larger grain size and reduced defect density. Furthermore, surface-modified homojunction perovskites are fabricated to efficiently extract charge carriers and enhance the efficiency of perovskite solar cells (PeSCs) by modulating the final PbI2 thickness before thermal annealing. Using these strategies, the best PeSC exhibits a power conversion efficiency of 13.41% for a small area (0.135 cm2), the highest value among sequential thermal deposition inorganic PeSCs, and 11.10% for a large area PeSC (1 cm2). This study presents an effective way to understand the crystal growth of thermally deposited perovskites and improve their performance in optoelectronic devices.

9.
Mater Horiz ; 11(12): 2926-2936, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38567487

RESUMO

Recently, inverted perovskite solar cells (PeSCs) have witnessed significant advancements; however, their long-term stability remains a challenge because of the oxidation of silver cathodes to form AgI by mobile iodides. To overcome this problem, we propose the integration of an electron-deficient naphthalene diimide-based zwitterion (NDI-ZI) as the cathode interlayer. Compared to the physical ion-blocking layer, it effectively captures ions by forming ionic bonds via electrostatic Coulombic interaction to suppress the migration of iodide and Ag ions. The NDI-ZI interlayer also suppresses the shunt paths and modulates the work function of the Ag electrode by forming interface dipoles, thereby enhancing charge extraction. FA0.85Cs0.15PbI3 based PeSCs incorporating NDI-ZI exhibited a noticeably high power conversion efficiency of up to 23.3% and outstanding stability, maintaining ∼80% of their initial performance over 1500 h at 85 °C and over 500 h under continuous 1-sun illumination. This study highlights the potential of a zwitterionic cathode interlayer in diverse perovskite optoelectronic devices, leading to their improved efficiency and stability.

10.
Pharm Biol ; 51(7): 930-5, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23570518

RESUMO

CONTEXT: Amomum xanthioides Wall. ex Baker (Zingiberaceae) is a tropical medicinal plant that is commonly utilized in the treatment of digestive system disorders in Asia for a long time. OBJECTIVE: This study aimed to evaluate the hepatoprotective effect and related mechanisms of A. xanthoides. MATERIALS AND METHODS: Sub-chronic liver injury was induced by dimethylnitrosamine (DMN, 10 mg/kg, three times per week for 3 weeks, i.p.) in rats. Water extract of A. xanthoides (WAX, 50 and 100 mg/kg) was given once a day for 3 weeks. RESULTS AND CONCLUSION: WAX (100 mg/kg) significantly attenuated the DMN-induced excessive release of alanine aminotransferase (123.6 IU/L), aspartate aminotransferase (227.9 IU/L), alkaline phosphatase (820.9 IU/L) and total bilirubin (0.50 g/dL) in serum (p < 0.01), and hydroxyproline (30.5 mg/g tissue) and malondialdehyde (MDA) (53.6 µM/g tissue) contents (p < 0.01) in liver tissue. Furthermore, WAX significantly ameliorated the depletion of total antioxidant capacity (2.54 µM/mg tissue), superoxide dismutase (0.30 U/mg tissue), glutathione (2.10 µM/mg tissue) and catalase (605.0 U/mg tissue) activities (p < 0.05 or p < 0.01) in liver tissue. Histopathological and immunohistochemical analyses indicated that WAX markedly reduced inflammation, necrosis, collagen accumulation and activation of hepatic satellite cells in the liver. Our findings demonstrated that A. xanthoides exerts favorable hepatoprotective effects via positive regulation of the antioxidative system.


Assuntos
Amomum/química , Antioxidantes/metabolismo , Hepatopatias/prevenção & controle , Extratos Vegetais/farmacologia , Animais , Dimetilnitrosamina/toxicidade , Relação Dose-Resposta a Droga , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Hepatopatias/patologia , Masculino , Medicina Tradicional do Leste Asiático , Extratos Vegetais/administração & dosagem , Substâncias Protetoras/administração & dosagem , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley
11.
J Mol Med (Berl) ; 99(12): 1783-1795, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34626199

RESUMO

We investigated the molecular mechanisms of paclitaxel resistance in TNBC using seven patient-derived xenograft (PDX) models and TNBC cell lines. Among the seven PDX models, four models showed resistance to paclitaxel. Dysregulation of JAK/STAT pathways and JAK2 copy number gains were observed in the four paclitaxel-resistant PDX tumors. In TNBC cell lines, silencing the JAK2 gene showed a significant but mild synergistic effect when combined with paclitaxel in vitro. However, JAK1/2 inhibitor treatment resulted in restoration of paclitaxel sensitivity in two out of four paclitaxel-resistant PDX models and JAK1/2 inhibitor alone significantly suppressed the tumor growth in one out of the two remaining PDX models. Transcriptome data derived from the murine microenvironmental cells revealed an enrichment of genes involved in the cell cycle processes among the four paclitaxel-resistant PDX tumors. Histologic examination of those PDX tumor tissues showed increased Ki67-positive fibroblasts in the tumor microenvironment. Among the four different cancer-associated fibroblast (CAF) subtypes, cycling CAF exhibiting features of active cell cycle was enriched in the paclitaxel-resistant PDX tumors. Additionally, fibroblasts treated with the conditioned media from the JAK2-silenced breast cancer cells showed downregulation of cell cycle-related genes. Our data suggest that the JAK2 gene may play a critical role in determining responses of TNBC to paclitaxel by modulating the intrinsic susceptibility of cancer cells against paclitaxel and also by eliciting functional transitions of CAF subtypes in the tumor microenvironment. KEY MESSAGES : We investigated the molecular mechanisms of paclitaxel resistance in TNBC. JAK2 signaling was associated with paclitaxel resistance in TNBC PDX models. Paclitaxel-resistant PDX tumors were enriched with microenvironment cCAF subpopulation. JAK2 regulated paclitaxel-resistant CAF phenotype transition.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Janus Quinase 2/genética , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/genética , Paclitaxel/uso terapêutico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Animais , Antineoplásicos Fitogênicos/farmacologia , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/metabolismo , Neoplasias Mamárias Experimentais/metabolismo , Camundongos , Nitrilas/farmacologia , Paclitaxel/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Microambiente Tumoral/efeitos dos fármacos
12.
Biol Pharm Bull ; 33(6): 1019-23, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20522970

RESUMO

Oxidized low-density lipoprotein (oxLDL) and reactive oxygen species (ROS) play key roles in the early stage of atherosclerosis. Nitric oxide (NO) and ROS are responsible for regulation of the transcriptional pathways of nuclear Factor-kappaB (NF-kappaB) and mitogen-activated protein kinase (MAPK), key regulators of cellular inflammatory and immune responses. Previously, we examined LDL-antioxidant activities of the nine flavonoids isolated from Sophora flavescens. Among these, two lavandulyl flavonoids, kurarinone (1) and kuraridin (2) inhibited inducible nitric oxide synthase (iNOS)-dependent NO production and ROS generation, and suppressed remarkably the expression of inflammatory cytokines, CCL2, tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta, and iNOS in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Moreover, compounds 1 and 2 attenuated NF-kappaB activation by inhibition of IkappaBalpha proteolysis and p65 nuclear translocation, as well as phosphorylation of extracellular signal-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK), and p38 MAP kinases.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Chalconas/farmacologia , Flavonoides/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Monoterpenos/farmacologia , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Sophora/química , Animais , Linhagem Celular , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Camundongos , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Espécies Reativas de Oxigênio/metabolismo
13.
J Obes Metab Syndr ; 29(2): 143-149, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32493836

RESUMO

BACKGROUND: Ketone bodies are a well-known metabolite from the utilization of fatty acids in the fasting state. Some studies have demonstrated the metabolic benefits of urinary ketones in a specific population in whom ketone bodies were detected. However, other studies described the influence of associated factors on the presence of urinary ketone bodies. In the present study, we analyzed lifestyle factors that are hypothesized to be related to the presence of ketone bodies in urine. METHODS: Data from the Korea National Health and Nutrition Examination Survey (KNHANES, 2014-2015) were analyzed. The urinary ketone-positive group was defined as the population in whom urinary ketones were detected. We compared differences in metabolic characteristics as well as lifestyle characteristics such as smoking, alcohol intake, education levels, and exercise between the urine ketone-positive and -negative groups. RESULTS: Of the 9,379 identified eligible subjects, the urine-ketone group showed metabolic benefits with respect to several factors such as body mass index, waist circumference, triglyceride, and high density lipoprotein cholesterol after adjustment for sex and age. A higher proportion of urinary ketones was associated with current smoking (P=0.050), high education level (P=0.008), and aerobic exercise (P=0.021). CONCLUSION: Aerobic exercise was identified as a factor associated with the presence of urinary ketones. It is also an important lifestyle intervention factor for the recovery of urinary ketones in patients with obesity.

14.
Adv Mater ; 32(11): e1907064, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32022987

RESUMO

Perishable foods at undesired temperatures can generate foodborne illnesses that present significant societal costs. To certify refrigeration succession in a food-supply chain, a flexible, easy-to-interpret, damage-tolerant, and sensitive time-temperature indicator (TTI) that uses a self-healing nanofiber mat is devised. This mat is opaque when refrigerated due to nanofiber-induced light scattering, but becomes irreversibly transparent at room temperature through self-healing-induced interfibrillar fusion leading to the appearance of a warning sign. The mat monitors both freezer (-20 °C) and chiller (2 °C) successions and its timer is tunable over the 0.5-22.5 h range through control of the polymer composition and film thickness. The thin mat itself serves as both a temperature sensor and display; it does not require modularization, accurately measures localized or gradient heat, and functions even after crushing, cutting, and when weight-loaded in a manner that existing TTIs cannot. It also contains no drainable chemicals and is attachable to various shapes because it operates through an intrinsic physical response.


Assuntos
Nanofibras/química , Polímeros/química , Refrigeração , Termômetros , Armazenamento de Alimentos , Nanofibras/ultraestrutura , Temperatura
15.
Nutr Cancer ; 61(5): 723-34, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19838947

RESUMO

Cinnamaldehydes have been reported to induce apoptosis in human carcinomas through the generation of reactive oxygen species (ROS). 2'-benzoyloxycinnamaldehyde (BCA) has been reported to inhibit tumor formation in H-ras12V transgenic mice. To see the antitumor effects of BCA, BCA was administrated intraperitoneally (50 mg/kg) to H-ras12V transgenic mice for 3 wk, and it was found that the hepatic tumor volume and the total number of tumors were decreased in BCA-treated mice as compared to control H-ras12V transgenic mice. To identify possible target genes responsible for BCA antitumor effects in H-ras12V transgenic mice, cDNA microarray analyses were performed comparing gene expression between BCA treated and control transgenic mice. We found that 42 genes were downregulated, and 40 genes were upregulated in the BCA-treated transgenic mice. The downregulated genes included several genes involved in ROS regulation and immune response (aconitase, metallothionein-1, metallothionein-2, and purine nucleoside phosphorylase). The expression of ROS-related genes, metallothionein 1 and metallothionein 2, was decreased more than twofold with BCA treatment (P < 0.001). It was confirmed by RT-PCR and immunohistochemical analyses. The inhibition of tumor formation and growth in H-ras12V transgenic mice by BCA was mediated through inhibition of the expression of the ROS scavengers metallothionein 1 and metallothionein 2.


Assuntos
Acroleína/análogos & derivados , Antineoplásicos/administração & dosagem , Benzoatos/administração & dosagem , Neoplasias Hepáticas Experimentais/prevenção & controle , Metalotioneína/genética , Acroleína/administração & dosagem , Acroleína/isolamento & purificação , Animais , Antineoplásicos/isolamento & purificação , Benzoatos/isolamento & purificação , Linhagem Celular Tumoral , Regulação para Baixo , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas Experimentais/patologia , Masculino , Metalotioneína/metabolismo , Camundongos , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Componentes Aéreos da Planta/química , Polygonaceae/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/metabolismo , Carga Tumoral , Proteínas ras/genética
16.
J Agric Food Chem ; 56(1): 92-8, 2008 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-18069795

RESUMO

Diarylheptanoids are known to have anti-inflammatory and anti-atherosclerotic activities in various cell types, including macrophages. 5- O-Methylhirsutanonol (5-MH) isolated from the leaves of Alnus japonica Steud exhibited the antioxidant activities on Cu (2+)- and AAPH-mediated low-density lipoprotein (LDL) oxidation in the thiobarbituric acid-reactive substances (TBARS) assay as well as the macrophage-mediated LDL oxidation. In the main study, we examined anti-inflammatory activities of 5- O-methylhirsutanonol (5-MH) on nuclear factor kappaB (NF-kappaB)-dependent nitric oxide (NO) production and expression of inducible nitric oxide synthease (iNOS) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages. 5-MH inhibited NO production with an IC 50 value of 14.5 microM and expression of both iNOS protein and iNOS mRNA in a parallel dose-response manner. Then, expression of inflammation-associated genes, such as TNF-alpha, COX-2, and IL-1beta, was suppressed by 5-MH, as determined by reverse transcriptase polymerase chain reaction analysis. Moreover, 5-MH attenuated NF-kappaB activation by inhibition of hyperphosphorylation of IkappaB-alpha and its subsequent proteolytic degradation and p65 nuclear translocation, as well as preventing DNA-binding ability. In addition, 5-MH suppressed the mRNA expression of the gene reactive oxygen species (ROS) concerned in the regulation of NF-kappaB signaling.


Assuntos
Anti-Inflamatórios/farmacologia , Diarileptanoides/farmacologia , Macrófagos/efeitos dos fármacos , NF-kappa B/farmacologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico/biossíntese , Animais , Linhagem Celular , Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Camundongos , RNA Mensageiro/análise
17.
Arch Pharm Res ; 31(4): 429-37, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18449499

RESUMO

Oxidized low-density lipoprotein (oxLDL) plays a key role in the inflammatory processes of atherosclerosis. Jaceosidin isolated from the methanolic extracts of the aerial parts of Artemisia princeps Pampanini cv. Sajabal was tested for antioxidant and anti-inflammatory activities. Jaceosidin inhibited the Cu(2+)-mediated LDL oxidation with IC(50) values of 10.2 microM in the thiobarbituric acid-reactive substances (TBARS) assay as well as the macrophage-mediated LDL oxidation. The antioxidant activities of jaceosidin were exhibited in the conjugated diene production, relative electrophoretic mobility, and apoB-100 fragmentation on copper-mediated LDL oxidation. Jaceosidin also inhibited the generation of reactive oxygen species (ROS) concerning in regulation of NF-kappaB signaling. And jaceosidin inhibited nuclear factor-kappa B (NF-kappaB) activity, nitric oxide (NO) production, and suppressed expression of inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-induced RAW264.7 macrophages.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Artemisia , Flavonoides/farmacologia , Macrófagos/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Anti-Inflamatórios/isolamento & purificação , Antioxidantes/isolamento & purificação , Apolipoproteína B-100/metabolismo , Artemisia/química , Linhagem Celular , Relação Dose-Resposta a Droga , Repressão Enzimática , Flavonoides/isolamento & purificação , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Lipoproteínas LDL/metabolismo , Macrófagos/metabolismo , Camundongos , Estrutura Molecular , Monócitos/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Componentes Aéreos da Planta , Regiões Promotoras Genéticas/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo , Transfecção
18.
Exp Mol Med ; 39(2): 160-9, 2007 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-17464177

RESUMO

In our previous study, two point mutants of apolipoprotein A-I, designated V156K and A158E, revealed peculiar characteristics in their lipid-free and lipid-bound states. In order to determine the putative therapeutic potential of these mutants, several in vitro and in vivo evaluations were conducted. In the lipid-free state, V156K showed more profound antioxidant activity against LDL oxidation than did the wildtype (WT) or A158E variants in an in vitro assay. In the lipid-bound state, V156K-rHDL showed an enhanced cholesterol delivery activity to HepG2 cells in a time-dependent manner, as compared to WT-rHDL, A158E-rHDL, and R173C-rHDL. We assessed the physiological activities of the mutants in circulation, using hypercholesterolemic mice (C57BL6/J). Palmitoyloleoyl phosphatidylcholine (POPC)-rHDL preparations containing each of the apoA-I variants were injected into the mice at a dosage of 30 mg of apoA-I/kg of body weight. Forty eight hours after injection, the sera of the V156K-rHDL injected group showed the most potent antioxidant abilities in the ferric acid removal assay. The V156K-rHDL- or R173C-rHDL-injected mice showed no atherosclerotic lesions and manifested striking increases in their serum apo-E levels, as compared to the mice injected with WT-rHDL or A158E-rHDL. In conclusion, V156K-rHDL exhibited the most pronounced antioxidant activity and anti-atherosclerotic activity, both in vitro and in vivo. These results support the notion that HDL-therapy may prove beneficial due to its capacity to induce accelerated cholesterol excretion, as well as its enhanced antioxidant and anti-inflammatory effects and lesion regression effect.


Assuntos
Aminoácidos/genética , Antioxidantes/metabolismo , Apolipoproteína A-I/genética , Aterosclerose/patologia , Hipercolesterolemia/patologia , Mutação Puntual/genética , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Colesterol/metabolismo , Cobre/farmacologia , Humanos , Hipercolesterolemia/induzido quimicamente , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução/efeitos dos fármacos , Proteínas Recombinantes/sangue
19.
J Agric Food Chem ; 55(23): 9457-64, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-17929893

RESUMO

Atherosclerosis is a chronic inflammatory disease that is characterized by infiltration of mononuclear lymphocytes into the intima through the expression of adhesion molecules on the arterial wall. In the present study, we report the inhibitory effects of two diarylheptanoids, 5-O-methylhirsutanonol (1) and oregonin (2), isolated from the methanolic extracts of Alnus japonica leaves, on the expression of adhesion molecules in human umbilical vein endothelial cells (HUVECs). Compounds 1 and 2 inhibited tumor necrosis factor (TNF)-alpha-induced up-regulation of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1), which also prevented adhesion of monocytes to HUVECs, and slightly suppressed the mRNA expression of the inflammation-associated gene interleukin-1beta (IL-1beta). A further study demonstrated the inhibitory effect of compound 1 on DNA-binding of nuclear factor kappaB (NF-kappaB) and on the phosphorylation and degradation of inhibitory factor kappaBalpha (IkappaBalpha) in TNF-alpha-stimulated HUVECs. These results indicate that compounds 1 and 2 may be useful in the prevention and treatment of atherosclerosis through attenuation of adhesion molecule expression by inhibition of NF-kappaB activation.


Assuntos
Diarileptanoides/farmacologia , Células Endoteliais/metabolismo , Expressão Gênica/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/genética , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/genética , Alnus/química , Humanos , Extratos Vegetais/química , Folhas de Planta/química , Veias Umbilicais
20.
J Agric Food Chem ; 54(15): 5369-74, 2006 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-16848519

RESUMO

Investigation on antioxidant compounds from the ethanolic extracts of Torreya nucifera leaves resulted in the isolation of abietane diterpenoids, a known 18-methylesterferruginol (1) and a new 18-dimethoxyferruginol (2). The structures of compounds 1 and 2 were elucidated on the basis of their spectroscopic analyses. Compounds 1 and 2 inhibited the Cu2+-mediated, 2,2'-azobis(2-amidinopropane)hydrochloride-mediated and 3-morpholinosydnonimine-1-mediated low-density lipoprotein (LDL) oxidation in the thiobarbituric acid-reactive substances assay as well as the macrophage-mediated LDL oxidation. Compounds 1 and 2 exhibited the potent antioxidant activities in the conjugated diene production, relative electrophoretic mobility, and apoB-100 fragmentation on copper-mediated LDL oxidation. Compound 1 also suppressed nitric oxide production and inducible nitric oxide synthase expression in lipopolysaccharide-stimulated RAW264.7 cells.


Assuntos
Abietanos/isolamento & purificação , Abietanos/farmacologia , Antioxidantes/farmacologia , Folhas de Planta/química , Taxaceae/química , Abietanos/química , Antioxidantes/química , Cobre/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoproteínas LDL/química
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