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1.
Nat Commun ; 15(1): 2730, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38548730

RESUMO

Lithium-ion batteries (LIBs) and plastics are pivotal components of modern society; nevertheless, their escalating production poses formidable challenges to resource sustainability and ecosystem integrity. Here, we showcase the transformation of spent lithium cobalt oxide (LCO) cathodes into photothermal catalysts capable of catalyzing the upcycling of diverse waste polyesters into high-value monomers. The distinctive Li deficiency in spent LCO induces a contraction in the Co-O6 unit cell, boosting the monomer yield exceeding that of pristine LCO by a factor of 10.24. A comprehensive life-cycle assessment underscores the economic viability of utilizing spent LCO as a photothermal catalyst, yielding returns of 129.6 $·kgLCO-1, surpassing traditional battery recycling returns (13-17 $·kgLCO-1). Solar-driven recycling 100,000 tons of PET can reduce 3.459 × 1011 kJ of electric energy and decrease 38,716 tons of greenhouse gas emissions. This work unveils a sustainable solution for the management of spent LIBs and plastics.

2.
Chem Commun (Camb) ; 60(21): 2828-2838, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38362916

RESUMO

Plastic waste in the environment causes significant environmental pollution. The potential of using chemical methods for upcycling plastic waste offers a dual solution to ensure resource sustainability and environmental restoration. This article provides a comprehensive overview of the latest technologies driven by solar-driven, electro/photoelectrochemical-catalytic, and microwave-assisted methods for the conversion of plastics into various valuable chemicals. It emphasizes selective conversion during the plastic transformation process, elucidates reaction pathways, and optimizes product selectivity. Finally, the article offers insights into the future developments of chemical upcycling of polyesters.

3.
Medicine (Baltimore) ; 103(2): e36870, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38215103

RESUMO

In the present prospective cohort research, we aimed to explore the serum levels of Acyl-CoA synthetase long-chain family member 4 (ACSL4) in patients with ST-segment elevation myocardial infarction (STEMI) and its association with 1-year major adverse cardiovascular events (MACE). This prospective cohort study recruited 507 patients who underwent percutaneous coronary intervention for the treatment of STEMI at our hospital during August 2019 to July 2022. The serum ACSL4, tumor necrosis factor-α, interleukin (IL)-6, IL-1ß, and C-reactive protein levels were measured by enzyme-linked immunosorbent assay. Demographic and clinical statistics were also collected. In addition, all patients were followed up for 1 year, and patients with MACE were defined as poor prognosis group. All data used SPSS 26.0 to statistical analyses. The poor prognosis group had significantly higher age and low-density leptin cholesterol (LDLC) levels compared to the favorable prognosis group (P < .05). STEMI patients exhibited significantly elevated serum levels of ACSL4, tumor necrosis factor-α, IL-6, IL-1ß, and C-reactive protein (P < .05). Serum ACSL4 and IL-1ß levels in the poor prognosis group were remarkably enhanced compared to the favorable prognosis group. Curvilinear regression analysis demonstrated that ACSL4 was associated with LDLC and IL-1ß. Moreover, ACSL4 (B = 0.138, 95% CI 1.108-1.189, P < .001), LDLC (B = 2.317, 95% CI 5.253-19.603, P < .001), and IL-1ß (B = 0.061, 95%CI 1.008-1.122, P = .025) levels were the risk factors for STEMI patients with 1-year MACE. This study showed that the serum ACSL4 levels was remarkably elevated in STEMI patients. This study might provide new targets and a comprehensive approach to cardiovascular protection in STEMI patients.


Assuntos
Coenzima A Ligases , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Proteína C-Reativa , Coenzima A Ligases/sangue , Coenzima A Ligases/química , Coração , Intervenção Coronária Percutânea/efeitos adversos , Prognóstico , Estudos Prospectivos , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Fator de Necrose Tumoral alfa
4.
Foods ; 12(22)2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38002198

RESUMO

The droplet size, zeta potential, interface protein adsorption rate, physical stability and microrheological properties of high-pressure-homogenization (HPH)-modified, dual-protein-based whey-soy (whey protein isolate-soy protein isolate) emulsions containing different oil phase concentrations (5%, 10% and 15%; w/w) were compared in this paper. The in vitro digestion characteristics and storage stability of the dual-protein emulsions before and after HPH treatment were also explored. The results show that with an increase in the oil phase concentration, the droplet size and interface protein adsorption rate of the untreated dual-protein emulsions increased, while the absolute value of the zeta potential decreased. When the oil phase concentration was 10% (w/w), HPH treatment could significantly reduce the droplet size of the dual-protein emulsion, increase the interface protein adsorption rate, and improve the elasticity of the emulsion. Compared with other oil phase concentrations, the physical stability of the dual-protein emulsion containing a 10% (w/w) oil phase concentration was the best, so the in vitro digestion characteristics and storage stability of the emulsions were studied. Compared with the control group, the droplet size of the HPH-modified dual-protein emulsion was significantly reduced after gastrointestinal digestion, and the in vitro digestibility and release of free amino groups both significantly increased. The storage stability results show that the HPH-modified dual-protein emulsion showed good stability under different storage methods, and the storage stability of the steam-sterilized dual-protein emulsion stored at room temperature was the best. These results provide a theoretical basis for the development of new nutritional and healthy dual-protein liquid products.

5.
Foods ; 12(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37761067

RESUMO

It has been proven that high-pressure homogenization (HPH) could improve the functional properties of proteins by modifying their structure. This study researched the effect of HPH on the structural and functional properties of whey-soy dual-protein (Soy Protein Isolation-Whey Protein Isolation, SPI-WPI). Different protein solution samples were treated with HPH at 30, 60, 90, 120 and 150 MPa, and the structure changed under different pressures was analyzed by measuring particle size, zeta potential, Fourier infrared spectrum (FTIR), fluorescence spectrum and scanning electron microscope (SEM). The results showed that HPH significantly reduced the particle size of SPI-WPI, changed the secondary and tertiary structures and improved the hydrophobic interaction between molecules. In addition, HPH significantly improved the solubility and emulsification of all proteins, and the improvement effect on SPI-WPI was significantly better than SPI and WPI. It was found that SPI-WPI treated with 60 MPa had the best physicochemical properties. Secondly, we researched the effect of HPH by 60 MPa on the emulsion properties of SPI-WPI. In this study, the SPI-WPI had the lowest surface tension compared to a single protein after HPH treatment. The emulsion droplet size was obviously decreased, and the elastic properties and physical stability of SPI-WPI emulsion were significantly enhanced. In conclusion, this study will provide a theoretical basis for the application of HPH in modifying the structure of dual-protein to improve its development and utilization in liquid specialty food.

6.
Food Chem X ; 18: 100721, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37397205

RESUMO

In this study, the quality indexes and sensory evaluation of Zanthoxylum armatum DC. from the main production areas in Southwest China were analyzed. Further, correlation analysis (CRA), principal component analysis (PCA) and cluster analysis (CA) were used to comprehensively evaluate the quality characteristics of Z. armatum. The results showed that the sensory indexes and physicochemical indexes of Z. armatum were significantly correlated. Five principal component factors were extracted from 12 indexes by PCA, and a comprehensive evaluation model of quality was established with Y = 0.2943Y1 + 0.2387Y2 + 0.1896Y3 + 0.1679Y4 + 0.1094Y5. On this basis, 21 producing areas were grouped into 4 groups and 3 groups by Q-type CA, respectively. R-type CA showed that the content of hydroxyl-sanshools, linalool content and b* value were the quality characteristic indexes of Z. armatum in Southwest China. This work provided an important theory and practice reference for Z. armatum quality evaluation and in-depth product development.

7.
Polymers (Basel) ; 15(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37112108

RESUMO

Construction of sustainable composite biofilms from natural biopolymers are greatly promising for advanced packaging applications due to their biodegradable, biocompatible, and renewable properties. In this work, sustainable advanced food packaging films are developed by incorporating lignin nanoparticles (LNPs) as green nanofillers to starch films. This seamless combination of bio-nanofiller with biopolymer matrix is enabled by the uniform size of nanofillers and the strong interfacial hydrogen bonding. As a result, the as-prepared biocomposites exhibit enhanced mechanical properties, thermal stability, and antioxidant activity. Moreover, they also present outstanding ultraviolet (UV) irradiation shielding performance. As a proof of concept in the application of food packaging, we evaluate the effect of composite films on delaying oxidative deterioration of soybean oil. The results indicate our composite film could significantly decrease peroxide value (POV), saponification value (SV), and acid value (AV) to delay oxidation of soybean oil during storage. Overall, this work provides a simple and effective method for the preparation of starch-based films with enhanced antioxidant and barrier properties for advanced food packaging applications.

8.
Bioact Mater ; 22: 466-481, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36330163

RESUMO

Vein grafts are widely used for coronary artery bypass grafting and hemodialysis access, but restenosis remains the "Achilles' heel" of these treatments. An extravascular stent is one wrapped around the vein graft and provides mechanical strength; it can buffer high arterial pressure and secondary vascular dilation of the vein to prevent restenosis. In this study, we developed a novel Nanocellulose-gelatin hydrogel, loaded with the drug Astragaloside IV (AS-IV) as an extravascular scaffold to investigate its ability to reduce restenosis. We found that the excellent physical and chemical properties of the drug AS-IV loaded Nanocellulose-gelatin hydrogel external stent limit graft vein expansion and make the stent biocompatible. We also found it can prevent restenosis by resisting endothelial-to-mesenchymal transition (EndMT) in vitro. It does so by activating autophagy, and AS-IV can enhance this effect both in vivo and in vitro. This study has added to existing research on the mechanism of extravascular stents in preventing restenosis of grafted veins. Furthermore, we have developed a novel extravascular stent for the prevention and treatment of restenosis. This will help optimize the clinical treatment plan of external stents and improve the prognosis in patients with vein grafts.

9.
Foods ; 11(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36359984

RESUMO

This study aimed to develop a novel pH-sensing biopolymer film based on red cabbage puree (RCP) incorporated with polyvinyl alcohol (PVA), which was utilized for monitoring fish freshness during storage at 25 °C. A homogenized RCP suspension with a mean particle size of 12.86 ± 0.03 µm and a total anthocyanin concentration of 292.17 ± 2.65 mg/L was directly used as a film-forming substance and anthocyanin source to blend with PVA, showing visual changes in color and ultraviolet-visible spectra within a pH of 2-12. Rheological and microstructural studies certified the strong interactions and good compatibility between the RCP and PVA, resulting in better mechanical properties and water resistance of the composite film than those of a pure RCP film, but without affecting its pH sensitivity. When used for fish freshness monitoring at 25 °C, the developed RCP/PVA film presented visible color differences from purple to yellow, which corresponded to the spoilage threshold of the total volatile basic nitrogen and the total viable count in fish samples. The study highlights that anthocyanin-rich purees of fruits and vegetables, in this case red cabbage puree, can be fully utilized to develop eco-friendly pH-sensing indicator films for intelligent food packaging.

10.
Int J Mol Sci ; 23(14)2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35887160

RESUMO

Our previous study extracted and identified an antibacterial peptide that was named NP-6. Herein, we investigated the physicochemical properties of NP-6, and elucidated the mechanisms underlying its antimicrobial activity against Staphylococcus aureus. The results showed that the hemolysis activity of NP-6 was 2.39 ± 0.13%, lower than Nisin A (3.91 ± 0.43%) at the same concentration (512 µg/mL). Negligible cytotoxicity towards RAW264.7 cells was found when the concentration of NP-6 was lower than 512 µg/mL. In addition, it could keep most of its activity in fetal bovine serum. Moreover, transmission electron microscopy, confocal laser scanning microscopy, and flow cytometry results showed that NP-6 can destroy the integrity of the bacterial cell membrane and increase the membrane permeability. Meanwhile, NP-6 had binding activity with bacterial DNA and RNA in vitro and strongly inhibited the intracellular ß-galactosidase activity of S. aureus. Our findings suggest that NP-6 could be a promising candidate against S. aureus.


Assuntos
Antibacterianos , Staphylococcus aureus , Antibacterianos/farmacologia , Bactérias , Membrana Celular , Testes de Sensibilidade Microbiana , Peptídeos/farmacologia
11.
Chemosphere ; 286(Pt 2): 131798, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34365175

RESUMO

Facile fractionation of lignocellulosic waste into useable forms is essential to achieve a multi-product treatment process especially when the resulting lignin streams are expected for high-value materials valorization. Despite acidic/alkaline deep eutectic solvents (DESs) are promising solvents for lignocellulosic waste fractionation, there is little information about their differences in the fractionation and lignin extraction profiles. In this work, four DESs that were cataloged to acidic types (formic acid-choline chloride, lactic acid-choline chloride) and alkaline types (monoethanolamine-choline chloride, glycerol-K2CO3) were investigated to compare their abilities of bamboo waste fractionation. Physicochemical properties of these resulting cellulose, lignin and derived lignin nanospheres (LNPs) were also assessed. Results showed that DESs could selectively extract lignin via cleaving lignin-carbohydrate linkages and lignin ether bonds. Acidic DESs pretreatments were more effective in biomass delignification (~95.0 %), while alkaline DESs showed better polysaccharide retention. Glycerol-K2CO3 LNPs exhibited much smaller sphere size (50-100 nm) while acidic DESs LNPs showed higher thermal stability due to higher extent of lignin condensation. In addition, MEA-ChCl could introduce amine groups onto lignin hydroxyl. This work provided insightful information for tailoring technique routes to selective lignocellulosic waste fractionation, while facilitating the downstream applications of the obtained cellulose/lignin.


Assuntos
Lignina , Nanosferas , Biomassa , Solventes
12.
Membranes (Basel) ; 12(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35054544

RESUMO

This work evaluated the improvement effects of lipids incorporation on water resistance of composite biodegradable film prepared with wheat bran cellulose/wheat gluten (WBC/WG) using an alkaline-ethanol film forming system. Four types of lipids, paraffin wax (PW), beeswax (BW), paraffin oil (PO), and oleic acid (OA), were tested. We found that PW, BW, and PO incorporation at 5-20% improved water vapor permeability (WVP) and surface hydrophobicity of prepared films. Particularly, incorporation of 15% BW could best improve the water resistance properties of the film, with the lowest WVP of 0.76 × 10-12 g/cm·s·Pa and largest water contact angle (WCA) of 86.18°. Incorporation of OA led to the decline in moisture barrier properties. SEM images revealed that different lipids incorporation changed the morphology and of the composite film, and cross-sectional morphology indicated BW-incorporated film obtained more uniform and compact structures compared to other films. Moreover, Fourier transform infrared spectra indicated that the incorporation of PW or BW enhanced the molecular interactions between the film components, confirmed by the chemical shift of characteristic peaks at 3277 and 1026 cm-1. Differential scanning calorimetry results revealed that incorporation of PW, BW, and PO increased films' melting point, decomposition temperatures, and enthalpy values. Furthermore, the presence of most lipids decreased tensile strength and elongation at the break of the film. Overall, the composite film containing 15% BW obtained the most promising water resistance performance and acceptable mechanical properties, and it thus most suitable as a hydrophobic biodegradable material for food packaging.

13.
Carbohydr Polym ; 250: 116872, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049820

RESUMO

While of enormous scientific interests, the super-wetting materials capable of one-step separation of oils and dyes from water are rare on the market. Besides, the disposal of the used materials themselves is still a challenge, mainly ascribed to their non-biodegradation. Herein, we report an all-cellulose composite membrane that can simultaneously remove oil and dye from water. The membrane was fabricated via a simple dip-coating process during which the filter paper was coated by a cellulose hydrogel layer. This cellulose hydrogel coating was discovered to play an essential role in the separation of oil/water emulsion. Meanwhile, the incorporation of citric acid remarkably improved the mechanical and adsorption properties of the membrane as it served as both the crosslinking agent and the active species for methylene blue adsorption. This work demonstrated a new strategy on the development of fully biodegradable materials for both high-efficiency oil/water separation and dye removal.

14.
Carbohydr Polym ; 245: 116554, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32718643

RESUMO

Nanocellulose-derived carbon is a promising material in energy storage because of its sustainability, low environmental impact, and large specific surface area. Herein, the skin secretion of Andrias davidianus (SSAD) is applied for the first time as the bio-nitrogen source to dope carbon aerogels from nanocellulose. Cellulose nanocrystal (CNC) is discovered to be very effective to address the dispersion problem of SSAD in water. After being homogeneously mixed with cellulose nanofiber (CNF), honeycomb-structured nanofibrous carbon aerogels are obtained via unidirectional freeze-drying of the SSAD/CNC/CNF mixture followed by high-temperature carbonization. Impressively, unlike those fragile carbon aerogels in many early works, the present ones exhibit outstanding elasticity in repeated compression and release tests. Moreover, a symmetric binder-free supercapacitor is assembled from the carbon aerogels, which exhibits improved electrochemical capacitive properties and cycling stability. And even after 500 compression and release cycles, the supercapacitor can still maintain high capacitive performance, indicating its superiorities in durability and electrochemical stability.


Assuntos
Secreções Corporais/química , Carbono/química , Géis/química , Nanofibras/química , Nanopartículas/química , Pele/metabolismo , Urodelos/fisiologia , Animais , Celulose/química , Elasticidade , Eletrodos , Temperatura Alta , Nitrogênio/química , Porosidade , Água/química
15.
Carbohydr Polym ; 231: 115736, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888822

RESUMO

A recently developed three-dimensional (3D) gel-printing technology, namely continuous liquid interface production (CLIP), was utilized to fabricate supramolecular shape memory hydrogels with high resolutions and complex 3D geometries. The UV-curable ink for CLIP was composed of hydrogel precursors (alginate and acrylamide) and a photo-initiator (ammonium persulfate). As expected, the double network formed from ionically crosslinked alginate and covalently crosslinked polyacrylamide endowed the printed hydrogels with excellent mechanical properties. Meanwhile, due to the reversible metal-ligand coordination interaction, the hydrogel could be temporarily immobilized into an optional shape after introducing calcium ions and return to its original shapes upon ion removal, exhibiting ion-triggered shape memory effect. Moreover, the presence of ions greatly improved the conductivity of the resultant hydrogels. Such 3D printed versatile hydrogels with complex geometries demonstrated the potential for selected applications, particularly in load-bearing materials and flexible electronic devices.

16.
Wei Sheng Yan Jiu ; 49(6): 908-913, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33413764

RESUMO

OBJECTIVE: To establish the relationship between hemoglobin level of 6-23 month infants and altitude of their living places, and to determine the adjusting hemoglobin values for infants in high altitude areas. METHODS: Conduct this study by using available data from Improvement of Nutrition in Children in Poor Rural Regions. 6-23 months infants were sampled with the method of combined multi-stage stratified cluster, PPS and random equidistant. Questionnaires were used to collect data of infants and their families, feeding practices and nutrition knowledge of caretakers. The weight and length were measured by the intelligent physical examination instrument. Hemoglobin was tested by HemoCue method with blood drop from finger tips. Altitude was checked by the residence regions. Linear regressions were used to analyze the relation quotation of hemoglobin and altitude, adjusting hemoglobin values were determined with the quotation. A comparison was observed among adjusting method of CDC, Dirren and the established. RESULTS: A total of 24 938 infants at age of 6-23 months were sampled from 140 counties, in 19 provinces in 2018. Data were from 22 207 male accounting for 51. 7% and 20 731 female, 48. 3%. The weight, height and hemoglobin were(77. 6±6. 2)cm, (9. 91±1. 62)kg and 11. 9 g/dL respectively. The altitude ranges from 10 m to 4236 m, averagely 893. 4 m. Anemia rates of the infants and adjusted with method from CDC, Dirren and this study were 18. 9%, 27. 5%, 22. 7% and 20. 3%, showing remarkable adjusting effect. This study obtained adjusting Hb value for 1000, 2000, 3000 and 4000 m were 0. 1, 0. 3, 0. 6 and 1. 2 g/dL respectively and noticeably lower than that of suggested by WHO. CONCLUSION: Adjusting hemoglobin values of 6-23 months were different from the used values.


Assuntos
Altitude , Anemia , Criança , Pré-Escolar , Feminino , Hemoglobinas/análise , Humanos , Lactente , Masculino , Estado Nutricional , População Rural
17.
Carbohydr Polym ; 207: 609-618, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30600046

RESUMO

Three-dimensional (3D) printing parts with excellent resolution and high performance are of great significance for scientific and engineering applications. In this study, a novel photocurable cellulose acetate butyrate (PC-CAB) resin was synthesized for continuous liquid interface production (CLIP) to construct 3D objects with high resolution, tailored mechanical properties, excellent chemical resistance and thermal stability. Particularly, the tensile and flexural strength of the CLIP 3D printed specimen could reach 44.67 and 64.53 MPa, respectively. Their solvent resistance against various organic solvents and strong acidic/basic solutions was evaluated. As expected, the 3D prints could well maintain their structural integrity and exhibited very low swelling ratios owing to the photo-induced chemical crosslinking structure. Notably, even after immersion in methylene chloride or 1.0 M acid/alkali for 3 h, the 3D prints still showed excellent mechanical and thermal properties. Further study demonstrated that when PC-CAB in the CLIP ink was optimized to 20 wt% while the photoinitiator (PI) was 0.5 wt%, complex-structured 3D printed objects with high surface quality could be obtained under specific printing parameters.

18.
J Biol Chem ; 294(7): 2486-2499, 2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30567741

RESUMO

Chronic benzene exposure is associated with hematotoxicity and the development of aplastic anemia and leukemia. However, the signaling pathways underlying benzene-induced hematotoxicity remain to be defined. Here, we investigated the role of protein phosphatase 2A (PP2A) in the regulation of benzene-induced hematotoxicity in a murine model. Male mice with a hepatocyte-specific homozygous deletion of the Ppp2r1a gene (encoding PP2A Aα subunit) (HO) and matched wildtype (WT) mice were exposed to benzene via inhalation at doses of 1, 10, and 100 ppm for 28 days. Peripheral white blood cell counts and activation of bone marrow progenitors were attenuated in the HO mice, indicating that Ppp2r1a deletion protects against benzene-induced hematotoxicity. Moreover, elevation of urinary S-phenyl mercapturic acid, a benzene metabolite, was much greater in WT mice than in HO mice. Real-time exhalation analysis revealed more exhaled benzene but fewer benzene metabolites in HO mice than in WT mice, possibly because of the down-regulation of Cyp2e1, encoding cytochrome P4502E1, in hepatocytes of the HO mice. Loss-of-function screening disclosed that PP2A complexes containing the B56α subunit participate in regulating Cyp2e1 expression. Notably, PP2A-B56α suppression in HepG2 cells resulted in persistent ß-catenin phosphorylation at Ser33-Ser37-Thr41 in response to CYP2E1 agonists. In parallel, nuclear translocation of ß-catenin was inhibited, concomitant with a remarkable decrease of Cyp2e1 expression. These findings support the notion that a regulatory cascade comprising PP2A-B56α, ß-catenin, and Cyp2e1 is involved in benzene-induced hematotoxicity, providing critical insight into the role of PP2A in responses to the environmental chemicals.


Assuntos
Benzeno/toxicidade , Citocromo P-450 CYP2E1/biossíntese , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Proteína Fosfatase 2/metabolismo , Transcrição Gênica/efeitos dos fármacos , Animais , Citocromo P-450 CYP2E1/genética , Células Hep G2 , Humanos , Camundongos , Camundongos Knockout , Proteína Fosfatase 2/genética
19.
Toxicol Appl Pharmacol ; 358: 56-67, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30195019

RESUMO

Previous studies have demonstrated that oxidative stress is implicated in benzene-induced hematotoxicity. However, the low dose-response effects and the mechanism underlying perturbation of hematopoiesis remain to be defined. This study aims to address the role of Nrf2 pathway in mediating benzene-induced hematotoxicity. Nrf2+/+ (wildtype, Nrf2-WT) and Nrf2-/- (knockout, Nrf2-KO) mice were administrated with benzene at doses of 0.1, 1.0, 10.0, 100.0 mg/kg by oral gavage for a consecutive 4 weeks (6 times/week). As a result, benzene exposure caused a decline of WBC and lymphocyte counts in a dose-dependent manner at a dose range from 1.0 to 100.0 mg/kg, while low dose benzene induced hormesis effects. Interestingly, Nrf2 deficiency seemed to relieve the decline of peripheral blood cell counts upon benzene exposure, indicating the involvement of Nrf2 in regulation of benzene-induced hematotoxicity. The suppression of phase II enzyme expression in Nrf2-KO mice resulted in considerable reduction in detoxification indicated by the decrease of urinary S-phenylmercapturic acid (SPMA), a metabolite of benzene. Ex vivo assay revealed enhanced cytotoxicity and oxidative stress were induced by benzene in Nrf2-KO mice. Notably, the depletion of Nrf2 triggered the proliferation and differentiation of hematopoietic cells, but induced aberrant morphological changes in periphery erythrocytes and bone marrow cells, implicating the compensatory effects carried on at the expense of induction of dysfunctional blood cells. Our findings provide a new insight into a low dose-response towards benzene-induced hematotoxicity and uncover the critical role of Nrf2 pathway in mediating abnormal hematopoiesis in response to oxidative stress.


Assuntos
Benzeno/toxicidade , Hematopoese/efeitos dos fármacos , Hematopoese/fisiologia , Fator 2 Relacionado a NF-E2/deficiência , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/fisiologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Relação Dose-Resposta a Droga , Eritrócitos/efeitos dos fármacos , Eritrócitos/fisiologia , Células HL-60 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Distribuição Aleatória
20.
Oncol Lett ; 15(5): 6377-6385, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29725397

RESUMO

The present study examined the effect of diallyl disulfide (DADS) on the invasion and migration ability of HL-60 cells with a high expression of parkinsonism associated deglycase (DJ-1) in the nucleus (HHDN), and its molecular mechanism. A western blot assay was used to measure the effects of DADS and an Src inhibitor on the expression of DJ-1 and the Src signal pathway in HHDN. The effects of DADS and Src inhibitors on the invasion and migration ability of HHDN was detected using Transwell migration and invasion chamber experiments. The experiments were divided into three groups: A control group (HL-60 cells), an empty vector group and a high expression group (HHDN cells). Western blot assays revealed that the expression of DJ-1 in HHDN was inhibited in a time-dependent manner following treatment with DADS for 24, 48 and 72 h. Following DADS treatment, the expression of phosphorylated Src (p-Src) and phosphorylated Fak (p-Fak) were significantly decreased in all groups compared with the untreated groups, however the expression level of Src, Fak and integrin did not change significantly. Western blot analysis results revealed that following treatment with DADS and Src inhibitor, the expression levels of p-Src and p-Fak significantly decreased in all three groups compared with untreated groups, whereas the expression levels of Src, Fak and integrin did not change significantly. The expression of DJ-1 in HHND was inhibited in time-dependent manner following treatment with DADS and Src inhibitor for 24, 48 and 72 h. Transwell migration and invasion assay results revealed that DADS and Src inhibitors may suppress migration and invasion in leukemic cells, and a combination of the two treatments may result in more efficient suppression. DADS may downregulate DJ-1-mediated invasion and migration in leukemic cells through suppressing the Src-Fak-Integrin signaling pathway, and the Src inhibitor may enhance the antitumor effect of DADS.

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