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1.
ACS Appl Mater Interfaces ; 12(4): 4849-4858, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31904212

RESUMO

The transport of ionic species through nanochannels plays an important role in the basic research and practical application of nanofluidic devices. Here, a visualized CdSe@ZIF-8/PAA nanochannel membrane was created by employing in situ growth of zeolite imidazole skeleton (ZIF-8) and CdSe quantum dots (CdSe QDs) on a porous anodized aluminum oxide (PAA) membrane surface using CdSe QDs, 2-methylimidazole, and zinc nitrate as the precursor solvents. ZIF-8 is a kind of metal-organic framework, a microporous material that possesses strong metal adsorption capacity. In addition, CdSe quantum dots have fluorescent properties. The nanochannel membrane detects copper ions (Cu2+) by quenching the fluorescence intensity by the interaction between Cu2+ and Se and S atoms. The direct potential of 5 V was applied to achieve Cu2+ enrichment at the nanochannel interface, and the fluorescence change was observed. The CdSe@ZIF-8/PAA nanochannel membrane has a good linear range of concentration (0.01 pM-1 µM) for Cu2+ detection. With the help of nanochannel enrichment, its detection limit reaches 4 fM. In addition, this nanochannel membrane has good selectivity for Cu2+.

2.
J Sci Food Agric ; 100(1): 315-324, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31525262

RESUMO

BACKGROUND: In order to utilize tilapia skin gelatin hydrolysate protein, which is normally discarded as industrial waste in the process of fish manufacture, we study the in vivo and in vitro angiotensin-I-converting enzyme (ACE) inhibitory activity of the peptide Leu-Ser-Gly-Tyr-Gly-Pro (LSGYGP). The aim was to provide a pharmacological basis of the development of minimal side effects of ACE inhibitors by comparative analysis with captopril in molecular docking. RESULTS: This peptide from protein-rich wastes showed excellent ACE inhibitory activity (IC50  = 2.577 µmol L-1 ) and exhibited a mixed noncompetitive inhibitory pattern with Lineweaver-Burk plots. Furthermore, LSGYGP and captopril groups both showed significant decreases in blood pressure after 6 h and maintained good digestive stability over 4 h. Molecular bond interactions differentiate competitive captopril upon hydrogen bond interactions and Zn(II) interaction. The C-terminal Pro generates three interactions (hydrogen bonds, hydrophilic interactions and Van der Waals interactions) in the peptide and effectively interacts with the S1 and S2 pockets of ACE. CONCLUSION: LSGYGP, with an IC50 value of 2.577 µmol L-1 , has an antihypertensive effect in spontaneously hypertensive rats. Through comparison with captopril, this study revealed that LSGYGP may be a potential food-derived ACE inhibitory peptide and could act as a functional food ingredient to prevent hypertension. © 2019 Society of Chemical Industry.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/química , Anti-Hipertensivos/química , Captopril/química , Hipertensão/tratamento farmacológico , Peptídeos/química , Sequência de Aminoácidos , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/metabolismo , Pressão Sanguínea/efeitos dos fármacos , Captopril/administração & dosagem , Ciclídeos , Digestão , Proteínas de Peixes/química , Trato Gastrointestinal/metabolismo , Humanos , Ligações de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Cinética , Masculino , Simulação de Acoplamento Molecular , Peptídeos/metabolismo , Peptídeos/farmacologia , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/metabolismo , Hidrolisados de Proteína/química , Hidrolisados de Proteína/metabolismo , Ratos , Ratos Endogâmicos SHR
3.
Water Environ Res ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31799785

RESUMO

As an emerging contaminant in the environment, microplastics have attracted worldwide attention. Although research methods on microplastics in the environment have been reported extensively, the data on microplastics obtained cannot be comparable due to different methods. In this work, we critically reviewed the analytical methods of microplastics, including sample collection, separation, identification, and quantification. Manta trawl and tweezers or cassette corers are used to collect water samples and sediments, respectively. For biota sample, internal organs need to be dissected and separated to obtain microplastics. Density differences are often used to separate microplastics from the sample matrix. Visual classification is one of the most common methods for identifying microplastics, and it can be better detected by combining it with other instruments. However, they are not suitable for detection nanoplastics, which may lead to underestimation of risk. The abundance of microplastics varies with the detection method. Thus, the analytical methods for microplastics need to be standardized as soon as possible. Meanwhile, new methods for analyzing nanoplastics are urgently needed. PRACTITIONER POINTS: Sampling, separation, identification, and quantification are important procedures. The sampling and separation methods for microplastics need to be standardized. The organic matter can be removed by digestion to facilitate identification. Combine microscope with analytical instruments to better identify microplastics. There is still a challenge to quantification of smaller-sized plastic particles.

4.
Food Nutr Res ; 632019.
Artigo em Inglês | MEDLINE | ID: mdl-31762729

RESUMO

Introduction: A previous study has shown that Ala-Thr-Pro-Gly-Asp-Glu-Gly (ATPGDEG) peptide identified from boiled abalone by-products has high antioxidant activities and antihypertensive effect. Objective: In this study, we further investigated its antiphotoaging activities by ultraviolet B (UVB)-induced HaCaT cells. Result: UVB irradiation significantly increased the content of intercellular reactive oxygen species (ROS) and the production of matrix metalloproteinases (MMPs) in HaCaT cells and decreased its content of collagen. First, the generation of intercellular ROS was reduced by abalone peptide in UVB-induced HaCaT cells. And activities of MMP-1 and MMP-9 were reduced by abalone peptide in a dose-dependent manner. Furthermore, western blot analysis demonstrated that abalone peptide downregulated the expression of p38, c-Jun N-terminal kinases, and extracellular signal-regulated kinases via mitogen-activated protein kinases (MAPKs) and NF-κB signaling to protect type I pro collagen and DNA damage. Molecular docking simulation confirms that abalone peptide inhibited activities of MMP-1 and MMP-9 by docking their active site, among them N-terminal Ala, C-terminal Gly, and Pro at the third position of N-terminal made a great contribution. Conclusion and recommendation: Abalone peptide could protect type I procollagen synthesis in UVB-irradiated HaCaT cells, and it is a potential peptide for the treatment of skin photoaging in the future.

5.
Environ Pollut ; 255(Pt 2): 113283, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31580990

RESUMO

Microplastics (particle size <5 mm) are an emerging contaminant for aquatic environmental, which have attracted increasing attention in worldwide range. In this study, an improved fluorescent staining method for detection and quantification of microplastics was developed based on thermal expansion and contraction. This method is effective in detection of polyethylene, polystyrene, polyvinyl chloride and polyethylene terephthalate plastic particles. In order to avoid error statistics caused by pretreatment, various characterizations of microplastics were measured after heated, such as microstructure, compositions and thermostability. The results showed that there was no significant damage to microplastics even under heating condition at 75 °C for 30 min, and the stained microplastics had strong stability for up to two months. Moreover, this method has been successfully applied to the quantification of microplastics in biological samples and result showed there were about 54 particles g-1 (dry weight) microplastics in the Sipunculus nudus. This new method provides a reliable method for quantitative analysis of microplastics in environment and biological tissue.


Assuntos
Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Fluoresceína/química , Corantes Fluorescentes/análise , Oxazinas , Fenazinas/química , Plásticos/análise , Polietileno/análise , Poliestirenos/análise , Cloreto de Polivinila
6.
Artigo em Inglês | MEDLINE | ID: mdl-31337157

RESUMO

In this paper, nitrogen-doped carbon quantum dots (N-CQDs) were synthesized by a solvothermal method using 1,2,4-triaminobenzene as a carbon precursor. The surface of the synthesized N-CQDs was modified with amino functional groups. The results indicated that N-CQDs had various N-related functional groups and chemical bonds and were amorphous in structure. At the same time, the quantum yield of N-CQDs was 5.11%, and the average lifetime of fluorescence decay was 5.79 ns. The synthesized N-CQDs showed good selectivity for and sensitivity to Ag+. A linear relationship between N-CQDs detection efficiency and Ag+ concentration was observed for concentration ranges of Ag+ corresponding to 0-10 µM and 10-30 µM. In addition, N-CQDs were used for the detection of trace Ag+ in food packaging material. The silver ion content of the sample determined by the N-CQDs detection method was 1.442 mg/L, with a relative error of 6.24% with respect to flame atomic absorption spectrometry, according to which the Ag+ content was 1.352 mg/L. This indicates that the N-CQDs detection method is reliable. Therefore, the N-CQDs prepared in this paper can detect Ag+ rapidly, simply, and sensitively and are expected to be a promising tool for the detection of trace Ag+ in food packaging materials.


Assuntos
Carbono/química , Embalagem de Alimentos , Nitrogênio/química , Pontos Quânticos , Prata/análise , Espectrometria de Fluorescência
7.
J Agric Food Chem ; 67(32): 8855-8867, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31343893

RESUMO

Abalone (Haliotis discus hannai) is a precious seafood in the market. It has been reported that biological active substances derived from abalone have anti-oxidative, anti-inflammatory, anti-bacterial, and anti-thrombosis potential. However, there were few studies to assess whether they have anti-cancer potential. In this study, we evaluated the anti-metastasis and anti-pro-angiogenic factors and mechanism of action of boiled abalone byproduct peptide (BABP, EMDEAQDPSEW) in human fibrosarcoma (HT1080) cells and human umbilical vein endothelial cells (HUVECs). The results demonstrated that BABP treatment significantly lowers migration and the invasion of HT1080 cells and HUVECs. BABP inhibits phorbol 12-myristate 13-acetate (PMA)-induced matrix metalloproteinase (MMP) expression and activity by blocking mitogen-activated protein kinases (MAPKs) and NF-κB signaling and hypoxia-induced vascular endothelial growth factor (VEGF) secretion and hypoxia inducible factor (HIF)-1α accumulation through suppressing the AKT/mTOR signal pathway. BABP treatment inhibits VEGF-induced VEGFR-2 expression and tube formation in HUVECs. The effect of BABP on anti-metastatic and anti-vascular activity in HT1080 cells and HUVECs revealed that BABP may be a potential pharmacophore for tumor therapy in the future.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Gastrópodes/química , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Peptídeos/farmacologia , Resíduos/análise , Inibidores da Angiogênese/química , Inibidores da Angiogênese/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Metástase Neoplásica , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/fisiopatologia , Peptídeos/química , Peptídeos/isolamento & purificação , Frutos do Mar/análise , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
8.
Nanomaterials (Basel) ; 9(7)2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31262004

RESUMO

Micro-nano composite material was prepared to adsorb Hg(II) ions via the co-precipitation method. Oyster shell (OS), Fe3O4 nanoparticles, and humic acid (HA) were used as the raw materials. The adhesion of nanoparticles to OS displayed by scanning electron microscopy (SEM), the appearance of the (311) plane of standard Fe3O4 derived from X-ray diffraction (XRD), and the transformation of pore sizes to 50 nm and 20 µm by mercury intrusion porosimetry (MIP) jointly revealed the successful grafting of HA-functionalized Fe3O4 onto the oyster shell surface. The vibrating sample magnetometer (VSM) results showed superparamagnetic properties of the novel adsorbent. The adsorption mechanism was investigated based on X-ray photoelectron spectroscopy (XPS) techniques, which showed the process of physicochemical adsorption while mercury was adsorbed as Hg(II). The effects of pH (3-7), initial solution concentration (2.5-30 mg·L-1), and contact time (0-5 h) on the adsorption of Hg(II) ions were studied in detail. The experimental data were well fitted to the Langmuir isotherm equation (R2 = 0.991) and were shown to follow a pseudo-second-order reaction model (R2 = 0.998). The maximum adsorption capacity of Hg(II) was shown to be 141.57 mg·g-1. In addition, this new adsorbent exhibited excellent selectivity.

9.
Mar Drugs ; 17(7)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340575

RESUMO

Angiotensin II (Ang II) is closely involved in endothelial injury during the development of hypertension. In this study, the protective effects of the tilapia by-product oligopeptide Leu-Ser-Gly-Tyr-Gly-Pro (LSGYGP) on oxidative stress and endothelial injury in Angiotensin II (Ang II)-stimulated human umbilical vein endothelial cells (HUVEC) were evaluated. LSGYGP dose-dependently suppressed the fluorescence intensities of nitric oxide (NO) and reactive oxygen species (ROS), inhibited the nuclear factor-kappa B (NF-κB) pathway, and reduced inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and endothelin-1 (ET-1) expression, as shown by western blot. In addition, it attenuated the expression of gamma-glutamyltransferase (GGT) and heme oxygenase 1 (HO-1), as well as increasing superoxide dismutase (SOD) and glutathione (GSH) expression through the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Other experiments revealed that LSGYGP increased the apoptotic inhibition ratio between cleaved-caspase-3/procaspase-3, reduced expressions of pro-apoptotic ratio between Bcl-2/Bax, inhibited phosphorylation of mitogen-activated protein kinases (MAPK), and increased phosphorylation of the serine/threonine kinase (Akt) pathway. Furthermore, LSGYGP significantly decreased Ang II-induced DNA damage in a comet assay, and molecular docking results showed that the steady interaction between LSGYGP with NF-κB may be attributed to hydrogen bonds. These results suggest that this oligopeptide is effective in protecting against Ang II-induced HUVEC injury through the reduction of oxidative stress and alleviating endothelial damage. Thus, it has the potential for the therapeutic treatment of hypertension-associated diseases.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Hipertensão/complicações , Oligopeptídeos/farmacologia , Tilápia , Doenças Vasculares/prevenção & controle , Angiotensina II/toxicidade , Animais , Endotélio Vascular/citologia , Endotélio Vascular/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipertensão/patologia , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/química , NF-kappa B/metabolismo , Oligopeptídeos/química , Estresse Oxidativo/efeitos dos fármacos , Ligação Proteica , Transdução de Sinais/efeitos dos fármacos , Doenças Vasculares/patologia
10.
Photochem Photobiol ; 95(6): 1424-1432, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31230361

RESUMO

In this study, we investigated the protective effects of a peptide (YGDEY, Tyr-Gly-Asp-Glu-Tyr) isolated from tilapia skin gelatin hydrolysates (TGHs), against UVB-induced photoaging in human keratinocytes (HaCaT) cells. Results showed that YGDEY significantly decreased levels of intracellular reactive oxygen species (ROS), increased antioxidant factors (Superoxide Dismutase, SOD and Glutathione, GSH) expression and maintained balance between GSH and GSSG in HaCaT cells. Comet assay shows that YGDEY can protect DNA from oxidative damage. Furthermore, it significantly inhibited MMP-1 (collagenase) and MMP-9 (gelatinase) expression and increased Type I procollagen production. In addition, the molecular docking study showed that YGDEY may form active sites with MMP-1 and MMP-9. Moreover, Western blot analysis was utilized to measure the protein levels of UVB-induced mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways. Therefore, these results suggested that YGDEY has a therapeutic effectiveness in prevention of UVB-induced cellular damage, and it is a candidate worthy of being developed as a potential natural antioxidant and food additive.

11.
Anal Chem ; 91(13): 8184-8191, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31140271

RESUMO

The transport of ions in nanochannels has received considerable interest owing to the unique transport properties and potential applications. In this study, ultrasmall nanochannels (0.8-1.2 nm) were fabricated in porous anodized aluminum (PAA) membrane in situ growth. 2-Methylimidazole and zinc nitrate were used as the reaction precursor solkution, and then zeolitic imidazolate framework (ZIF-8) nanoparticles were sufficiently filled in PAA nanochannels to form a ZIF-8/PAA nanochannels composite membrane. Because ZIF-8 is a microporous material and has a strong ability to adsorb heavy metals, the composite membrane was used as a biosensor to detect lead ion (Pb2+) by the coordination interaction between Pb2+ and nitrogen atoms. The detection limit reached to 0.03 nM due to the enrichment of nanochannels under electric field. The sensor has a good linear range for Pb2+ from 10 nM to 10 µM.

12.
Chem Commun (Camb) ; 55(45): 6397-6400, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31094376

RESUMO

A single gold nanopore with high surface enhanced Raman spectroscopy (SERS) activity is fabricated on the tip of a glass nanopipette. Polystyrene (PS) nanospheres can be recognized from the SERS spectrum while passing through the single nanopore.

13.
Mar Drugs ; 17(4)2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022939

RESUMO

Vasculogenic mimicry (VM) formed by tumor cells plays a vital role in the progress of tumor, because it provides nutrition for tumor cells and takes away the metabolites. Therefore, the inhibition of VM is crucial to the clinical treatment of tumors. In this study, we investigated the anti-tumor effect of a novel peptide, KVEPQDPSEW (AATP), isolated from abalone (Haliotis discus hannai) on HT1080 cells by migration, invasion analysis and the mode of action. The results showed that AATP effectively inhibited MMPs by blocking MAPKs and NF-κB pathways, leading to the downregulation of metastasis of tumor cells. Moreover, AATP significantly inhibited VM and pro-angiogenic factors, including VEGF and MMPs by suppression of AKT/mTOR signaling. In addition, molecular docking was used to study the interaction of AATP and HIF-1α, and the results showed that AATP was combined with an active site of HIF-1α by a hydrogen bond. The effect of AATP on anti-metastatic and anti-vascular in HT1080 cells revealed that AATP may be a potential lead compound for treatment of tumors in the future.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Gastrópodes/química , Neoplasias/tratamento farmacológico , Peptídeos/farmacologia , Adulto , Inibidores da Angiogênese/química , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Metaloproteinases da Matriz/metabolismo , NF-kappa B/metabolismo , Metástase Neoplásica , Neoplasias/irrigação sanguínea , Neoplasias/metabolismo , Neoplasias/patologia , Proteína Oncogênica v-akt/metabolismo , Peptídeos/química , Peptídeos/isolamento & purificação , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Esferoides Celulares/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , eIF-2 Quinase/metabolismo
14.
Sensors (Basel) ; 19(6)2019 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-30893770

RESUMO

A method is developed for detecting the concentration of sodium thiocyanate (NaSCN) in milk based on surface-enhanced Raman scattering (SERS) technology. A trichloroacetic acid solution can be used to enhance the SERS signal because of its function in promoting the aggregation of Ag nanoparticles (Ag NPs). Meanwhile, the protein in milk would be precipitated as trichloroacetic acid added and the interference from protein could be reduced during the detection. In this work, the enhancement factor (EF) is 7. 56 × 105 for sodium thiocyanate in water and the limit of detection (LOD) is 0.002 mg/L. Meanwhile, this method can be used to detect the concentration of sodium thiocyanate in milk. Results show that SERS intensity increased as the concentration of sodium thiocyanate increase from 10 to 100 mg/L. The linear correlation coefficient is R² = 0.998 and the detection limit is 0.04 mg/L. It is observed that the concentration of sodium thiocyanate does not exceed the standard in the three kinds of milk. The confirmed credibility of SERS detection is compared with conventional methods.


Assuntos
Nanopartículas Metálicas/química , Leite/química , Prata/química , Análise Espectral Raman/métodos , Tiocianatos/análise , Animais , Limite de Detecção , Água/química
15.
J Neuroimmunol ; 330: 143-151, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30884275

RESUMO

Seahorse has been used as a traditional medicine in Southeast Asian countries for a long time. A compound, 2'-Hydroxy-5'-Methoxyacetophenone (2H5M) isolated from seahorse, Hippocampus kuda, was tested for its anti-inflammatory effect in lipopolysaccharides (LPS)-stimulated BV-2 cells and RAW264.7 cells. MTT assay indicated that 2H5M has no cytotoxicity on two kinds of cells. The concentration of nitric oxide (NO) measured by Griess Reaction System showed that 2H5M could significantly inhibit the NO concentration. The ELISA results showed that 2H5M could suppress the secretion of TNF-α in a dose-dependent manner. Moreover, western blot analysis was utilized to measure the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways. Electrophoretic mobility shift assay (EMSA) demonstrated that 2H5M reduced NF-κB DNA binding activity. Furthermore, the molecular docking study showed that 2H5M can form active sites with NF-κB. Collectively, these results indicated that 2H5M possesses anti-inflammatory effects and may have a potential application in inflammatory disorders in the future.


Assuntos
Anti-Inflamatórios/farmacologia , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/toxicidade , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Anti-Inflamatórios/isolamento & purificação , Relação Dose-Resposta a Droga , Mediadores da Inflamação/antagonistas & inibidores , Camundongos , NF-kappa B/antagonistas & inibidores , Células RAW 264.7 , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Smegmamorpha
16.
Nutrients ; 11(2)2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30781878

RESUMO

According to a previous study, YGDEY from tilapia fish skin gelatin hydrolysates has strong free radical scavenging activity. In the present study, the protective effect of YGDEY against oxidative stress induced by ethanol in HepG2 cells was investigated. First, cells were incubated with YGDEY (10, 20, 50, and 100 µM) to assess cytotoxicity, and there was no significant change in cell viability. Next, it was established that YGDEY decreased the production of reactive oxygen species (ROS). Western blot results indicated that YGDEY increased the levels of superoxide dismutase (SOD) and glutathione (GSH) and decreased the expression of gamma-glutamyltransferase (GGT) in HepG2 cells. It was then revealed that YGDEY markedly reduced the expressions of bax and cleaved-caspase-3 (c-caspase-3); inhibited phosphorylation of Akt, IκB-α, p65, and p38; and increased the level of bcl-2. Moreover, the comet assay showed that YGDEY effectively decreased the amount of ethanol-induced DNA damage. Thus, YGDEY protected HepG2 cells from alcohol-induced injury by inhibiting oxidative stress, and this may be associated with the Akt/nuclear factor-κB (NF-κB)/mitogen-activated protein kinase (MAPK) signal transduction pathways. These results demonstrate that YGDEY from tilapia fish skin gelatin hydrolysates protects HepG2 cells from oxidative stress, making it a potential functional food ingredient.


Assuntos
Etanol/toxicidade , Gelatina/química , Peptídeos/farmacologia , Tilápia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Peptídeos/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Pele/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-30519264

RESUMO

Hippocampus is a traditional medicine in China, which can be used for treating tumors, aging, fatigue, thrombosis, inflammation, hypertension, prostatic hyperplasia, and other diseases. 1-(5-Bromo-2-hydroxy-4-methoxyphenyl)ethanone [SE1] from seahorse (Hippocampus kuda Bleeler) has been shown to suppress proinflammatory responses. In the present study, SE1 potently inhibited gelatin digestion by MMP-9 induced by phorbol 12-myristate 13-acetate (PMA) and migration of human fibrosarcoma HT1080 cells in dose-dependent manner. Moreover, western blot analysis and immunofluorescence analysis have been studied on MAPKs (ERK1/2, p38 kinase and JNK) and NF-κB (p65 and IκB), which refer to the clear molecular mechanism. The results indicated that SE1 significantly suppressed the phosphorylation of mitogen-activated protein kinases (MAPK: p38 kinase and JNK) and NF-κB. Finally, molecular docking result showed SE1 interacts with TYR245 and HIS226 of MMP-9 by hydrogen bond and Pi-Pi bond to suppress MMP-9 activity. This data suggested that the SE1 may possess therapeutic and preventive potential for the treatment of MMP-9 related disorders.

18.
Nanomaterials (Basel) ; 8(11)2018 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-30413087

RESUMO

A degradable and antibacterial sodium alginate film containing functional Au-TiO2 nanocomposites for food packaging was successfully developed. The Au-TiO2 nanocomposites are synthesized hydrothermally and mixed with the alginate solution to form the film by a casting method. The Au-TiO2 nanocomposites enable the film with excellent visible light absorption and transfer ability with the light absorption rang covering UV⁻visible wavelength (300⁻800 nm) and induce the increase of the film water contact angle from 40° to 74°, which contributes to the film shape stability. Furthermore, compared to the TiO2 nanoparticle-incorporated film, the antibacterial ability of Au-TiO2/sodium alginate composite film is improved approximately by 60% and 50% against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively, in light conditions. The antibacterial property of the film arises from the increased production of reactive oxygen species (ROS) induced by the surface plasmonic resonance of Au nanoparticles. The degradable and antibacterial properties render the composite film of great application potential in food packaging industry.

19.
J Agric Food Chem ; 66(44): 11812-11822, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30339011

RESUMO

Prodrug, in which the inactive parent drug with good bioavailability is metabolized into an active drug in the body, is one of the main strategies to target the disease site to improve the drug efficiency and reduce the adverse effects of chemotherapy. Because of the good capability of chemical modification, zein, a plant derived protein, and drugs can be conjugated through environmentally sensitive links to form prodrugs capable of triggered drug release. In this study, a novel prodrug was synthesized using paclitaxel (PTX), zein, and a disulfide linker, and nanoparticles were formed by self-assembly of the prodrug. An effective in vitro triggered release, 80-90% in 5 min, of the prodrug based nanoparticles (zein-S-S-PTX_NP) was successfully approached. The cytotoxicity of zein-S-S-PTX_NP as well as the zein encapsulation of PTX (zein_PTX_NP) and pure PTX on HeLa cells and NIH/3T3 fibroblast cells was tested using MTS assay. It showed that, after the treatment of zein-S-S-PTX_NP at the equivalent PTX concentrations of 0.1, 0.5, 1, and 5 µg/mL, respectively, zein-S-S-PTX_NP had zero damage to normal cells but a similar cytotoxicity to cancer cells as pure PTX. In the animal study, the tumor was 50% of the original size after the treatment of zein-S-S-PTX_NP for 9 days with 3 doses. This study suggested that the novel prodrug based nanoparticle zein-S-S-PTX_NP could be a promising approach in chemotherapy with targeted delivery, improved efficacy, and reduced side effects.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Paclitaxel/administração & dosagem , Paclitaxel/química , Pró-Fármacos/administração & dosagem , Pró-Fármacos/química , Zeína/química , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos/instrumentação , Liberação Controlada de Fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Oxirredução
20.
Environ Sci Pollut Res Int ; 25(30): 30575-30584, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30173386

RESUMO

A heterogeneous catalyst (M-N-rGO) composed of stability enhanced magnetic iron oxide nanoparticles and nitrogen-doped reduced graphene oxide was synthesized and characterized by SEM, XRD, BET, and XPS. It showed excellent catalytic degradation properties in advanced oxidation technology. In the presence of 200 mg/L catalyst and 135 mg/L persulfate at pH 5, 95% of 10-20 mg/L methylene blue could be degraded in 90 min with the TOC removal efficiency of 50%. The rate constant based on pseudo-first-order kinetics ranged from 0.0227 to 0.0488/min in the temperature range of 15 to 32 °C, and the activation energy was 32.5 kJ/mol. Under the optimal operation conditions, 20 mg/L of 2,4-dichlorophneol (2,4-DCP) could be removed almost completely. EPR analysis showed that sulfate and hydroxyl radicals were responsible for degradation of pollutants, and radical quenching experiments indicated that nonradical pathway also played a role in pollutant removal. And a mechanism for M-N-rGO and persulfate system was elucidated. This catalyst was easy for preparation, low-cost, highly effective, convenient for separation, and could be used effectively for four times through 0.1 mol/L H2SO4 regeneration. It provided a choice for wastewater treatment in practice.


Assuntos
Nitrogênio/química , Sulfatos/química , Águas Residuárias/química , Poluentes Químicos da Água/química , Catálise , Grafite/química , Radical Hidroxila , Magnetismo , Azul de Metileno , Oxirredução , Óxidos/química , Eliminação de Resíduos Líquidos
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