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1.
Mater Sci Eng C Mater Biol Appl ; 92: 477-488, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30184773

RESUMO

Most cancer patients die as a consequence of distant metastases, which are frequently unresponsive to cancer therapy. This study focuses on the anti-tumorigenic and anti-metastatic properties of tangeretin-zinc oxide quantum dots (Tan-ZnO QDs) against the NCI-H358 cell line. Tan-ZnO QDs are pH-sensitive and capitalize on the acidic pH maintained in the tumor microenvironment; therefore, targeted drug delivery is directed specifically to cancer cells, leaving the normal cells less affected. Tan was loaded into synthesized ZnO QDs, and drug loading was analyzed using Fourier transform infrared (FTIR) spectroscopy and ultraviolet-visible (UV-Vis) spectrometry. Crystalline phase and particle size were measured using transmission electron microscopy (TEM) and X-ray diffraction (XRD). Drug release was evaluated in buffered solutions with differing pH for up to 15 h. The results confirmed stable drug release (80%) in an acidic pH. Tan-ZnO QDs induced significant cytotoxicity in NCI-H358 metastatic cells, while not markedly affecting HK-2 human normal cells. Morphology of treated H358 cells analyzed via atomic force microscopy (AFM) showed an increased surface roughness and pores. Further, the number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells increased after treatment with Tan-ZnO QDs. DNA fragmentation was also induced after treatment with increasing concentrations of Tan-ZnO QDs in H358 cells. We also confirmed regulation of apoptosis via expression levels of Bax and Bcl-2 proteins; G2/M phase cell cycle arrest was observed. Additionally, cell proliferation and migration drastically decreased, and cell invasion and migration, hallmarks of metastasis, were significantly inhibited in H358 cells. Matrix metalloproteinase (MMP)2 and MMP9, markers of metastasis, as well as vascular endothelial growth factor (VEGF), a marker of angiogenesis, were significantly downregulated upon treatment with Tan-ZnO QDs. In conclusion, our novel formulation destabilized H358 cells by using its acidic tumor microenvironment, thereby regulating cell apoptosis, proliferation, and metastatic properties.


Assuntos
Apoptose/efeitos dos fármacos , Flavonas , Neoplasias Pulmonares/tratamento farmacológico , Pontos Quânticos , Óxido de Zinco , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Flavonas/química , Flavonas/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Óxido de Zinco/química , Óxido de Zinco/farmacologia
2.
Acta Histochem ; 120(5): 477-489, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29853304

RESUMO

Oxidative stress plays a crucial role in the progression of alcoholic liver diseases and substances of antioxidant property are of special interest for therapeutic purposes. We investigated the hepatoprotective effect of leaf extracts of Sasa quelpaertensis, an edible bamboo mainly cultivated in Jeju Island, South Korea. We examined the cytotoxicity of different extracts (distilled water, 20-80% EtOH) of S. quelpaertensis on HepG2 cells and their hepatoprotective effect on HepG2 cells stimulated by ethanol (800 mM, 24 h). Furthermore, we measured reactive oxygen species (ROS) production, ethanol toxicity induced cell death, and the activity of antioxidant enzymes. In in vivo experiments, liver damage was induced by oral administration of 5 g/kg ethanol with or without potent ethanol extract of S. quelpaertensis (10 or 100 mg/kg) 12 h interval for a total of 3 doses. Only 80% ethanol extract of S. quelpaertensis (SQEE80) exhibited cytoprotective effect on HepG2 cells against alcohol-induced toxicity. SQEE80 treatment (250, 500 µg/mL) in ethanol exposed HepG2 cells showed significant attenuation of ROS production and ethanol toxicity induced cell death. Furthermore, SQEE80 markedly increased the activity of antioxidant enzyme glutathione peroxidase 1 in ethanol exposed HepG2 cells compared to ethanol stimulated cells. In in vivo experiments, SQEE80 treatment evidently suppressed the alcohol-induced histopathological changes in liver, serum ethanol content, and expression of cytochrome P450 2E1. Furthermore, SQEE80 significantly reversed the reduction of glutathione level in the ethanol challenged liver. Taken together, we suggest the possibility of developing SQEE80 as a natural hepatoprotective substance in attenuating alcohol-induced oxidative stress.


Assuntos
Antioxidantes/química , Hepatopatias Alcoólicas/tratamento farmacológico , Extratos Vegetais/química , Folhas de Planta/química , Sasa/química , Animais , Antioxidantes/uso terapêutico , Western Blotting , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico
3.
J Ethnopharmacol ; 224: 335-348, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-29906537

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Sasa quelpaertensis Nakai is an edible dwarf bamboo cultivated mainly in Jeju Island, South Korea and its leaf displays various health-promoting properties including antioxidant scavenging. AIM OF THE STUDY: In this study, we aimed at elucidating its hepatoprotective effect against alcohol-induced fatty liver. METHODS: In in vitro study, we evaluated the cytotoxicity and hepatoprotective effect of different solvent fractions (aqua, butanol, chloroform, ethyl acetate and hexane) of 80% EtOH extract of S. quelpaertensis Nakai leaf. In vivo experiment performed using binge alcohol consumption model. RESULTS: Although all five fractions (0-1000 µg/mL) were non-cytotoxic to HepG2 cells, only ethyl acetate fraction (SQEA), rich in phenolic acids such as p-coumaric acid and flavonoids particularly myristin, showed hepatoprotective effect against EtOH (400 mM) in HepG2 cells. Furthermore, SQEA significantly decreased the ethanol induced cell death and enhanced the cell proliferation. In in vivo experiment using binge consumption model (5 g of EtOH/kg body weight in every 12 h for 3 times), SQEA treatment (10, 50 and 100 mg/kg) markedly reduced the alcohol induced histopathological changes and serum EtOH content, and reversed the reduction of glutathione level in ethanol challenged livers. Further, it suppressed the expression of cytochrome P450 2E1 (CYP2E1). In particular, SQEA activated AMP activated protein kinase (AMPK) pathway, and decreased the expression of tumor necrosis factor receptor-1 (TNFR1), which attenuated lipogenesis via decreased expression of fatty acid synthase (FAS). Inhibited lipogenesis due to SQEA treatment directed towards decreased perilipin-2 expression. These results indicate that SQEA has hypolipidemic effect which is mediated by decreased oxidative stress, increased fatty acid oxidation response and decreased lipogenesis. CONCLUSION: Our results suggest the possibility of developing SQEA as a natural hepatoprotective agent potent in attenuating alcohol-induced fatty liver.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Fígado Gorduroso Alcoólico/tratamento farmacológico , Flavonoides , Hidroxibenzoatos , Substâncias Protetoras , Sasa , Animais , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocromo P-450 CYP2E1/metabolismo , Fígado Gorduroso Alcoólico/metabolismo , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Glutationa/metabolismo , Células Hep G2 , Humanos , Hidroxibenzoatos/farmacologia , Hidroxibenzoatos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos Endogâmicos C57BL , Perilipina-2/metabolismo , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Triglicerídeos/metabolismo
4.
Sci Rep ; 5: 15178, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26478189

RESUMO

Conventional surface acoustic wave - electrostatic deposition (SAW-ED) technology is struggling to compete with other thin film fabrication technologies because of its limitation in atomizing high density solutions or solutions with strong inter-particle bonding that requires very high frequency (100 MHz) and power. In this study, a hybrid surface acoustic wave - electrohydrodynamic atomization (SAW-EHDA) system has been introduced to overcome this problem by integrating EHDA with SAW to achieve the deposition of different types of conductive inks at lower frequency (19.8 MHZ) and power. Three materials, Poly [2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEH-PPV), Zinc Oxide (ZnO), and Poly(3, 4-ethylenedioxythiophene):Polystyrene Sulfonate ( PEDOT: PSS) have been successfully deposited as thin films through the hybrid SAW-EHDA. The films showed good morphological, chemical, electrical, and optical characteristics. To further evaluate the characteristics of deposited films, a humidity sensor was fabricated with active layer of PEDOT: PSS deposited using the SAW-EHDA system. The response of sensor was outstanding and much better when compared to similar sensors fabricated using other manufacturing techniques. The results of the device and the films' characteristics suggest that the hybrid SAW-EHDA technology has high potential to efficiently produce wide variety of thin films and thus predict its promising future in certain areas of printed electronics.

5.
Appl Opt ; 44(5): 742-50, 2005 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-15751855

RESUMO

A new optical security system for the protection of personal identification information is proposed. First, authentication of the encrypted personal information is carried out by primary recognition of a personal identification number (PIN) with the proposed multiplexed minimum average correlation energy phase-encrypted (MMACE_p) filter. The MMACE_p filter, synthesized with phase-encrypted training images, can increase the discrimination capability and prevent the leak of personal identification information. After the PIN is recognized, speedy authentication of personal information can be achieved through one-to-one optical correlation by means of the optical wavelet filter. The possibility of information counterfeiting can be significantly decreased with the double-identification process. Simulation results demonstrate the effectiveness of the proposed technique.


Assuntos
Biometria/métodos , Segurança Computacional , Face/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Armazenamento e Recuperação da Informação/métodos , Óptica e Fotônica , Reconhecimento Automatizado de Padrão/métodos , Algoritmos , Gráficos por Computador , Humanos , Processamento de Sinais Assistido por Computador
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