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1.
Food Chem ; 458: 140230, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38954954

RESUMEN

This study evaluates vacuum drying (VD), microwave drying (MD), hot air drying (HAD), and freeze drying (FD), on the color and microstructure changes of Ascophyllum nodosum (A. nodosum), which affect the extraction of polyphenols and flavonoids. During drying, VD and FD show slight color change and looser structure, aiding in active compound preservation and extraction. Polyphenols extracted from A. nodosum (PEAn) using these methods show higher anti-tyrosinase activity, with VD treatment exhibiting the strongest inhibition. Kinetic studies demonstrate competitive inhibition between PEAn and tyrosinase. The binding constant (Ki) values indicate that PEAn treated with VD exhibits the most effective inhibition on tyrosinase, and the Zeta potential suggests the formation of the most stable complex. Circular dichroism (CD) spectroscopy shows significant enzyme rearrangement with VD-treated PEAn. Molecular docking confirms strong binding affinity. This study aims to enhance the utility of A. nodosum and develop novel uses for tyrosinase inhibitors in food.

2.
Int J Biol Macromol ; 275(Pt 2): 133253, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38945709

RESUMEN

Chlorophyll (Chl) is the predominant pigment in green plants that can act as a food color and possesses various functional activities. However, its instability and rapid degradation on heating compromise the sensory qualities of its products. This study aimed to enhance the heat resistance of Chl by forming complex coacervates with two negatively charged polysaccharides, sodium alginate (SA) and K-carrageenan (KC). Dynamic light scattering and scanning electron microscopy analyses confirmed the formation of coacervates between Chl and the polysaccharides, whereas Fourier-transform infrared spectroscopy revealed that hydrogen bonding and electrostatic attraction were the primary forces behind complex formation. Electron spin resonance and thermodynamic studies further revealed that these complexes bolstered the thermal stability of Chl, with a maximum improvement of 70.38 % in t1/2 and a reduction of 50.72 % in the degradation rate constant. In addition, the antioxidant capacity of Chl was enhanced up to 35 %. Therefore, this study offers a novel approach to Chl preservation and suggests a viable alternative to artificial pigments in food products.


Asunto(s)
Clorofila , Polisacáridos , Termodinámica , Clorofila/química , Cinética , Polisacáridos/química , Antioxidantes/química , Alginatos/química , Color , Carragenina/química
3.
Curr Med Imaging ; 20: e15734056283964, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38462832

RESUMEN

BACKGROUND: Embryonal carcinoma is a rare tissue type in germ cell tumors. According to our literature review, metastatic embryonal carcinoma misdiagnosed as lymphoma because of its high similarity to lymphoma is extremely rare and has not been reported yet. CASE PRESENTATION: A 46-year-old middle adulthood male presented with unexplained fever, night sweats, abdominal distension for 3 months, and weight loss of around 7kg during almost 6 months, which is extremely similar to lymphoma from the clinical features and imaging examinations. After a clear diagnosis, the case not only obtained the opportunity of surgery but was also exempted from radiotherapy. The treatment effect was good. We report a case of rare metastatic embryonal carcinoma, which can provide insight into the diagnosis and treatment of embryonal carcinoma. CONCLUSION: Metastatic embryonal carcinoma of abdominal lymph nodes can be highly similar to lymphoma; the diagnosis can only be based on clinical manifestations and imaging examination but also combined with patient history, tumor markers and biochemical examination. However, the final diagnosis depends on pathological biopsy.


Asunto(s)
Carcinoma Embrionario , Linfoma , Humanos , Masculino , Persona de Mediana Edad , Linfoma/diagnóstico por imagen , Carcinoma Embrionario/patología , Carcinoma Embrionario/diagnóstico por imagen , Diagnóstico Diferencial , Metástasis Linfática/diagnóstico por imagen , Tomografía Computarizada por Rayos X
4.
Small Methods ; : e2301508, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38375977

RESUMEN

Perovskite nanocrystals are embedded into metal-organic frameworks (MOFs) to create composites with high light absorption coefficients, tunable electronic properties, high specific surface area, and metal atom tunability for enhanced photocatalytic carban dioxide (CO2 ) reduction. However, existing perovskite-MOF structures with a large particle size are achieved based on Pb source adsorption into the pores of MOFs, which can significantly break down the porous structure, thereby resulting in a decreased specific surface area and impacting CO2 adsorption. Herein, a novel perovskite-MOF structure based on the synthesis of bimetallic Pb-containing MOFs and post-processing to convert Pb to CsPbBr3 nanocrystals (NCs) is proposed. It is discovered that the additional Pb is not introduced by adsorption, but instead engages in coordination and generates Pb-N. The produced ZIF-8@CsPbBr3 NCs are ≈40 nm and have an ultra-high specific surface area of 1325.08 m2 g-1 , and excellent photovoltaic characteristics, which are beneficial for photocatalytic CO2 reduction. The electronic conversion rate of composites is 450 mol g-1 h-1 , which is more than three times that of pure perovskites. Additionally, the superior reduction capacity is sustained after undergoing four cycles. Density Functional Thoery (DFT) simulations are used to explore the 3D charge density at the ZIF-8@CsPbBr3 NCs interface to better understand the electrical structure.

5.
Int J Biol Macromol ; 261(Pt 1): 129788, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38290637

RESUMEN

Currently, people eat Undaria pinnatifida (UP) in a single way, and processing homogeneity is serious. However, UP has not gained any traction in the 3D printing industry to date. This study explored the incorporation of soy protein isolate (SPI), pea protein (PP), xanthan gum (XG), guar gum (GG), corn starch (CS), and potato starch (PS) into UP slurry liquid, the primary component of the study, to formulate a UP gel ink. The UP gel 3D printing ink system based on UP paste was established and characterized. The results show that hydrogen bonds are formed, and three-dimensional gel network structure is formed in all UP gel inks. UP gel inks containing high concentrations of SPI and GG exhibited good texture and rheological qualities and good 3D printing effect, with storage modulus (G') values of 8440.405 ± 3.893 and 8111.730 ± 3.585 Pa. The loss of modulus (G″) values were 1409.107 ± 3.524 and 1071.673 ± 3.669 Pa. Unfortunately, the properties of other UP gel inks are not suitable, resulting in poor 3D printing results. The food 3D printing method developed in this study provides valuable insights for expanding food 3D printing material choices and achieving high-value applications of UP.


Asunto(s)
Algas Comestibles , Gastrópodos , Almidón , Undaria , Humanos , Animales , Tinta , Alimentos , Excipientes , Cetonas , Impresión Tridimensional
6.
J Cancer Res Clin Oncol ; 149(10): 7125-7138, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36881149

RESUMEN

PURPOSE: Spread through air spaces (STAS) is a crucial invasive mode of lung cancer and has been shown to be associated with early recurrence and metastasis. We aimed to develop a prognostic risk assessment model for stage I lung adenocarcinoma based on STAS and other pathological features and to explore the potential relationship between CXCL-8, Smad2, Snail, and STAS. METHODS: 312 patients who underwent surgery at Harbin Medical University Cancer Hospital with pathologically diagnosed stage I lung adenocarcinoma were reviewed in the study. STAS and other pathological features were identified by H&E staining, and a prognostic risk assessment model was established. The expression levels of CXCL8, Smad2, and Snail were determined by immunohistochemistry. RESULTS: The nomogram was established based on age, smoking history, STAS, tumor lymphocyte infiltration, tissue subtype, nuclear grade, and tumor size. The C-index for DFS was (training set 0.84 vs validation set 0.77) and for OS was (training set 0.83 vs validation set 0.78). Decision curve analysis showed that the model constructed has a better net benefit than traditional reporting. The prognostic risk score validated the risk stratification value for stage I lung adenocarcinoma. STAS was an important prognostic factor associated with stronger invasiveness and higher expression of CXCL8, Smad2, and Snail. CXCL8 was associated with poorer DFS and OS. CONCLUSIONS: We developed and validated a survival risk assessment model and the prognostic risk score formula for stage I lung adenocarcinoma. Additionally, we found that CXCL8 could be used as a potential biomarker for STAS and poor prognosis, and its mechanism may be related to EMT.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Pronóstico , Estadificación de Neoplasias , Invasividad Neoplásica/patología , Adenocarcinoma del Pulmón/patología , Neoplasias Pulmonares/patología , Estudios Retrospectivos , Recurrencia Local de Neoplasia/patología
7.
J Sci Food Agric ; 102(8): 3308-3315, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34813108

RESUMEN

BACKGROUND: To ameliorate egg white gel's salinity and undesirable texture characteristics during curing, different metal ions (K+ , Mg2+ , Ca2+ , Zn2+ ) were used to replace sodium chloride (NaCl) to simulate salted eggs partially. The effects of these ions on the physicochemical properties, microstructure, and gel characteristics of egg white protein were studied. RESULTS: Low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) analysis showed that adding K+ , Mg2+ , Ca2+ , and Zn2+ could decrease immobile water content and increase free water content in egg white gel. Circular dichroism/fluorescence spectrophotometry (CD/FL) analysis showed that substitutive addition of K+ , Mg2+ , Ca2+, and Zn2+ changed the conformational structure of the protein, which was not conducive to the formation of the three-dimensional mesh gel structure. Differential scanning calorimetry (DSC) results show that the addition of four metal ions could reduce the thermal denaturation temperature of egg white gel. Scanning electron microscopy (SEM) showed that the gel structure of egg white in the zinc chloride (ZnCl2 ) group was rougher and more chaotic, the crosslinking degree was worse, so it was not suitable for low sodium salted egg preparations. The gel strength of the calcium chloride (CaCl2 ) group was significantly higher than other groups (P < 0.05), while the gel strength of the potassium chloride (KCl) group was similar to the NaCl group (P > 0.05). CONCLUSION: CaCl2 and KCl could be used as partial NaCl substitutes to study the addition level and ratio further and improve salted egg white quality. © 2021 Society of Chemical Industry.


Asunto(s)
Manipulación de Alimentos , Cloruro de Sodio , Cloruro de Calcio , Manipulación de Alimentos/métodos , Iones , Metales , Cloruro de Potasio , Cloruro de Sodio/análisis , Agua/análisis
8.
Langmuir ; 37(39): 11520-11525, 2021 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-34555896

RESUMEN

Lead halide perovskite quantum dots (QDs) are known as prospective optoelectronic device materials because of their excellent luminescence, extraordinary photoelectric performance, and specific octahedron framework. Herein, we report a cost-effective approach for synthesizing highly stable CH3NH3PbBr3 QDs in low-polarity binary solvents without nitrogen protection. The CH3NH3PbBr3 QDs are tunable from 1.2 to 4.2 nm by adjusting the proportion of oleic acid and oleylamine as capping ligands. The photoluminescence quantum yield of CH3NH3PbBr3 QDs can reach 87.4%. The fluorescence can maintain over 80% of its earliest emission intensity under the atmosphere after 5 days, which is much better than that (∼10%) of QDs with ligand-assisted reprecipitation. The possible reaction mechanism of preparing CH3NH3PbBr3 QDs was also addressed. Notably, such a strategy can be applied extensively in the preparation of other lead halide perovskite QDs. Furthermore, the as-prepared thick PMMA-coated CH3NH3PbBr3 QDs were further conjoined with a red luminescence powder on a blue InGaN chip to obtain a powerful efficiency (45.4 lm W-1) warm white light-emitting diode.

9.
Chemosphere ; 222: 91-97, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30690405

RESUMEN

In the study, zebrafish were exposed to 0 and 200 µg/L Zn for 8 weeks, and then both groups were transferred to water including 0, 100, and 200 µg/L Cd for 4 days, respectively. Acute Cd exposure caused negative effects on stress defense, immune, and metal transport systems by increasing lipid peroxidation, iNOS activity and mRNA levels of il-6 and inos, and decreasing Cu/Zn-SOD and HSP70 levels, and mRNA levels of sod1, cat, hsp70, p65, mtf-1, znt5, zip7, atp7a, and atp7b. Lipid peroxidation was significantly reduced by Zn pre-exposure under Cd exposure, which may be explained by the enhanced stress defense capacity and the weaken inflammatory response. Firstly, Zn pre-exposure increased MTs and HSP70 levels and CAT activity in Cd-free water, which may facilitate fish quick response to Cd. Secondly, Zn pre-exposure reduced Cd accumulation at 100 and 200 µg/L Cd, down-regulated il-6 and il-1ß at 100 µg/L Cd and p65 at 200 µg/L Cd, and increased Cu/Zn-SOD and CAT activities at 200 µg/L Cd. Thirdly, Zn pre-exposure alone up-regulated transcription factors (hsf1, hsf2, and mtf-1, and nrf2) and their target genes (sod1, cat, hsp70, and mt2) under Cd exposure in a dose-dependent manner. It should be noted that Zn pre-exposure down-regulated several metal transport genes dramatically at 0 and 100 µg/L Cd, which may be an important mechanism for reducing Cd import into livers. Overall, long-term and environmental Zn pre-exposure mitigated Cd toxicity by the enhanced stress defense capacity and the down-regulated metal transport and inflammatory responses.


Asunto(s)
Cadmio/farmacología , Homeostasis/efectos de los fármacos , Hígado/metabolismo , Pez Cebra/metabolismo , Zinc/farmacología , Animales , Proteínas HSP70 de Choque Térmico/metabolismo , Inflamación , Peroxidación de Lípido , Estrés Fisiológico/efectos de los fármacos , Factores de Transcripción , Contaminantes Químicos del Agua/farmacología
10.
Aquat Toxicol ; 207: 153-162, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30572175

RESUMEN

Effects on short-term (6 h) and long-term (96 h) exposure to cadmium (Cd) at 0.1, 0.5 and 2.5 mg/L in microalga Dunaliella salina were assessed using both physiological end points and gene expression analysis. Different physiological responses between the short-term and long-term exposures were observed. Upon 6 h after Cd exposure, lipid peroxidation and cell ultrastructure remained unchanged, while contents of chlorophyll a, chlorophyll b, carotenoids were increased at 0.5 and 2.5 mg/L Cd. Contrarily, 96 h after Cd exposure, lipid peroxidation levels were increased, while pigments content was decreased, and damaged cell ultrastructure was apparent at 2.5 mg/L Cd. Activities of antioxidant enzymes (APX, SOD, GST, GPX, and GR) changed differently both at 6 h and 96 h after Cd exposure. Upon 6 h after Cd exposure, SOD and GST activity increased at all three doses, GR and GPX activity increased at 0.5 mg/L Cd while APX activity increased at 0.1 mg/L Cd. Contrarily, 96 h after Cd exposure, activities of all the antioxidant enzymes increased both at 0.1 and 0.5 mg/L Cd; but there was a decrease in SOD and GR activity in D. salina exposed to 2.5 mg/L Cd. RNA-seq and qRT-PCR analyses indicated that genes involved in ROS-scavenge, photosystem, and ribosome functions were differentially expressed. The most significantly enriched function was the ribosome, in which more than 30 ribosome genes were up-regulated at 6 h but down-regulated at 96 h after Cd exposure at 2.5 mg/L. Our study indicated for the first time that genes encoding ribosomal proteins are the primary target for Cd in microalgae, which allowed gaining new insights into temporal dynamics of toxicity and adaptive response pathways in microalgae exposed to metals.


Asunto(s)
Cadmio/toxicidad , Chlorophyta/genética , Chlorophyta/fisiología , Depuradores de Radicales Libres/metabolismo , Proteínas del Complejo del Centro de Reacción Fotosintética/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ribosomas/metabolismo , Transcripción Genética , Antioxidantes/metabolismo , Chlorophyta/efectos de los fármacos , Chlorophyta/ultraestructura , Peroxidación de Lípido/efectos de los fármacos , Microalgas/genética , Microalgas/crecimiento & desarrollo , Microalgas/fisiología , Microalgas/ultraestructura , Modelos Biológicos , Estrés Oxidativo/efectos de los fármacos , Pigmentos Biológicos/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ribosomas/efectos de los fármacos , Factores de Tiempo , Transcripción Genética/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad
11.
Chemosphere ; 214: 85-93, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30253258

RESUMEN

Responses to zinc (Zn) during exposure have well studied but the effects after the exposure are commonly neglected. In the study, non-specific immune response to zinc in blood and spleen of zebrafish was evaluated after exposure. At first, fish were subjected to 0 (control) and 200 µg/L zinc (Zn) for 6 weeks. Specific growth rate, survival rate, blood albumin level, and the activities of Cu/Zn-SOD and iNOS were not significantly changed by Zn exposure. Conversely, Zn increased the levels of globulin and hemoglobin, CAT activity, and mRNA levels of nrf2, sod1, cat, hsf1, hsp70, p65, il-6, il-1ß, tnf-α and inos. In the second experiment, zebrafish were transferred to a recovery period for 4 and 8 days. The increased activities of Cu/Zn-SOD and CAT and the up-regulated mRNA levels of nrf2, cat, p65, tnf-α, and inos still were observed. In the third experiment, zebrafish from 4 d post-exposure were re-exposed to the high levels of Zn and cadmium (Cd) (600, 1200 µg/L Zn; 100, 200 µg/L Cd) for 4 days. 100 µg/L Cd caused a higher survival rate in the Zn-exposed fish than the control, suggesting Zn pre-exposure might develop the tolerance to Zn and Cd. Although transcriptional levels of sod1, hsf1, hsf2, hsp70, il-6 and il-1ß and activity levels of iNOS recovered to the control levels at 4 and 8 d post-exposure, differences in magnitude of responsiveness were observed between normal fish and Zn-exposed fish. Overall, Zn acclimation persisted when fish recovered, which provides a new perspective about Zn toxicology.


Asunto(s)
Contaminantes Químicos del Agua/farmacología , Pez Cebra/inmunología , Zinc/farmacología , Animales , Cadmio/metabolismo , Tolerancia a Medicamentos , Inmunidad Innata , Bazo/efectos de los fármacos , Pez Cebra/fisiología
12.
Fish Shellfish Immunol ; 72: 1-8, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29074130

RESUMEN

Zebrafish were exposed to 0, 2.5 and 5 µg/L cadmium (Cd) for 10 weeks, and then each group was exposed to 26 °C(control) and 32 °C (high temperature) for 7 days. 22 indicators were compared between 26 °C and 32 °C in the spleen, including body weight, LPO and NO levels, activity levels of Cu/Zn-SOD, CAT and iNOS, MTs protein levels, and mRNA levels of Nrf2, Cu/Zn-SOD, CAT, HSF1, HSF2, HSP70, MTF-1, MTs, IL-6, IL-10, IL-1ß, TNF-α, iNOS and NF-κB. Most indicators were not significantly affected by heat in fish from no Cd pollution. However, almost all of indicators were responsive to heat in fish pre-exposed to Cd. Several indicators were sensitive to heat in fish pre-exposed to 2.5 µg/L Cd such as iNOS activities, and mRNA levels of iNOS and IL-10. Most other indicators were sensitive to heat in fish pre-exposed to 5 µg/L. The mRNA levels of HSP70 and MTF-1 were up-regulated by heat in fish pre-exposed to 0, 2.5 and 5 µg/L Cd. However, the magnitude of increase was the greatest in fish pre-exposed to 5 µg/L Cd. These differences between control and high temperature would serve as biomarkers to distinguish healthy from Cd-polluted group. The findings imply that metal pollution history should be carefully considered when screening heat biomarkers in fish.


Asunto(s)
Cadmio/metabolismo , Calor/efectos adversos , Inmunidad Innata , Estrés Oxidativo , Contaminantes Químicos del Agua/metabolismo , Pez Cebra/metabolismo , Animales , Biomarcadores/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Masculino
13.
Sci Total Environ ; 618: 1363-1370, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29042086

RESUMEN

In this study, female zebrafish (Danio rerio) were exposed to 26°C or 34°C, 0 or 197µg/L cadmium (Cd), singly or in combination for 7days. Multiple stress-related indicators were evaluated in the liver. Mortality, lipid peroxidation (LPO) and ultrastructural damage increased significantly by Cd exposure alone, and were not affected by heat alone. Interestingly, the combined exposure increased LPO, ultrastructural damage, and mortality compared with Cd exposure alone. The results indicated that elevated temperature increased Cd toxicity, which could be explained by several reasons. Firstly, Cd-exposed fish failed to activate the antioxidant defense system under heat stress. Secondly, expression levels of heat shock protein 70 (HSP70) were not significantly up-regulated by heat in Cd-exposed fish but increased by 117 times in Cd-free fish. Besides, hypermethylation of heat shock factor (HSF) binding motif in HSP70 promoter was observed during the combined exposure, indicating that simultaneous exposure may have partially suppressed the cytoprotective up-regulation of HSP70. Thirdly, heat induced an immunosuppressive effect in Cd-exposed fish, as reflected by the reduced mRNA and activity levels of nitric oxide synthase (iNOS) and interleukin-1ß (IL-1ß) expression levels. Finally, heat down-regulated Zir-, Irt-like protein 8 (ZIP8) and copper transporter 1 (CTR1) and up-regulated metallothioneins (MTs) in Cd-exposed fish, possibly suggesting Cu and Zn depletion and Cd accumulation. Hence, our data provide evidences that warmer temperatures can potentiate Cd toxicity, involved in the regulation of gene transcription, enzymatic activity, and DNA methylation. We found that heat indicators showed varied sensitivity between normal and Cd-exposed fish, emphasizing that the field metal pollution should be carefully considered when evaluating effects of climate change.


Asunto(s)
Cadmio/toxicidad , Calor , Estrés Fisiológico/fisiología , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/fisiología , Animales , Antioxidantes/metabolismo , Proteínas de Transporte de Catión/metabolismo , Transportador de Cobre 1 , Femenino , Proteínas HSP70 de Choque Térmico/metabolismo , Interleucina-1beta , Peroxidación de Lípido/efectos de los fármacos , Hígado/metabolismo , Metalotioneína/metabolismo
14.
Aquat Toxicol ; 191: 1-9, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28763775

RESUMEN

Environmental stressors such as high temperature and metal exposure may occur sequentially, simultaneously, previously in aquatic ecosystems. However, information about whether responses to high temperature depend on Cd exposure history is still unknown in fish. Zebrafish were exposed to 0 (group 1), 2.5 (group 2) and 5µg/L (group 3) cadmium (Cd) for 10 weeks, and then each group was subjected to Cd-free water maintained at 26°C and 32°C for 7days respectively. 26 indicators were used to compare differences between 26°C and 32°C in the liver of female zebrafish, including 5 biochemical indicators (activity of Cu/Zn-SOD, CAT and iNOS; LPO; MT protein), 8 molecular indicators of oxidative stress (mRNA levels of Nrf2, Cu/Zn-SOD, CAT, HSF1, HSF2, HSP70, MTF-1 and MT), 5 molecular indicators of inflammation (mRNA levels of IL-6, IL-1ß, TNF-α, iNOS and NF-κB), 8 molecular indicators of metal transport (mRNA levels of, ZnT1, ZnT5, ZIP8, ZIP10, ATP7A, ATP7B and CTR1). All biochemical indicators were unchanged in group 1 and changed in group 2 and 3. Contrarily, differences were observed in almost all of molecular indicators of inflammation and metal transport in group 1, about half in group 2, and few in group 3. We also found that all molecular indicators of oxidative stress in group 2 and fewer in group 1 and 3 were significantly affected by heat. Our data indicated that heat indicators of oxidative stress, inflammation and metal transport showed dependence of previous cadmium exposure in the liver of zebrafish, emphasizing metal pollution history should be carefully considered when evaluating heat stress in fish.


Asunto(s)
Cadmio/toxicidad , Calor , Hígado/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Proteínas de Pez Cebra/metabolismo , Pez Cebra , Animales , Transporte Biológico , Biomarcadores/metabolismo , Cadmio/metabolismo , Relación Dosis-Respuesta a Droga , Femenino , Expresión Génica/efectos de los fármacos , Expresión Génica/inmunología , Inflamación , Hígado/enzimología , Hígado/inmunología , Estrés Oxidativo/genética , Estrés Oxidativo/inmunología , Contaminantes Químicos del Agua/metabolismo , Pez Cebra/inmunología , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
15.
Aquat Toxicol ; 190: 104-111, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28704659

RESUMEN

The working hypothesis for this study was that moderate heat stress would alleviate the deleterious effects of subsequent cadmium (Cd) exposure on fish. Thus, zebrafish (Danio rerio) were subjected to water maintained at 26°C and 34°C for 4days, and then exposed to 0 or 200µg/L Cd for 1 week at 26°C. Multiple indicators were measured from livers of zebrafish at different levels, including DNA, RNA, protein and enzymatic activity associated with oxidative stress, inflammation and metal transport. The ameliorative effect of preheatinging on Cd toxicity was demonstrated. In the Cd-exposed groups, preheating decreased mortality and lipid peroxidation, increased activity levels of catalase (CAT) and copper/zinc-superoxide dismutase (Cu/Zn-SOD), and up-regulated mRNA levels of heat shock protein 70 (HSP70) and heat shock factor 2 (HSF2). Preheating also mitigated Cd-induced increases in protein and mRNA levels of metallothioneins (MTs), and mRNA levels of several inflammation-related genes. Furthermore, preheating alone dramatically up-regulated mRNA levels of genes related to antioxidant and immune defenses, zinc and copper transporters, protein folding, and reduced methylation levels in the HSF binding motif of the HSP70 promoter. Overall, preheating-induced accumulation of transcripts via demethylation might support the rapid defense responses at post-transcriptional levels caused by subsequent Cd exposure, indicating an adaptive mechanism for organisms exposed to one mild stressor followed by another.


Asunto(s)
Cadmio/toxicidad , Metilación de ADN/efectos de los fármacos , Hígado/efectos de los fármacos , Termotolerancia/fisiología , Transcripción Genética/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/metabolismo , Animales , Proteínas HSP70 de Choque Térmico/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Peroxidación de Lípido/genética , Hígado/metabolismo , Regiones Promotoras Genéticas , Regulación hacia Arriba , Pez Cebra/genética
16.
Aquat Toxicol ; 188: 64-71, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28458151

RESUMEN

In natural environments, fish survive in polluted water by cadmium (Cd) throughout their whole life cycle. However, little information is available on Cd toxicity considering a life cycle assessment. The present study investigated effects of environmental levels of cadmium (0, 2.5, and 5µg/L) on immune responses in liver and spleen of zebrafish for 15 weeks, from embryos to sexually maturity. Nitric oxide (NO) levels and iNOS activity declined in liver and spleen of zebrafish exposed to 5µg/L Cd, suggesting an immunosuppressive effect. The result was further supported by the decreased transcriptional levels of proinflammatory cytokines by Cd, such as interleukin-6 (IL-6), interleukin-10 (IL-10), interleukin-1ß (IL-1ß), and tumour necrosis factor-α (TNF-α) in liver. However, a sharp increase in the mRNA levels of these cytokines was observed in spleen of zebrafish exposed to Cd. The increased mRNA expression of these proinflammatory cytokines may be the secondary effect following immunosuppression and just reflect a compensatory mechanism for coping with the decreased immunity, which may explain an increase in mRNA levels and a decrease in iNOS activity in spleen of zebrafish exposed to Cd. In liver, the down-regulated mRNA levels of iNOS paralleled with the decreased iNOS activity, suggesting a synchronous response from a molecular level to a biochemical level. Positive correlations between mRNA expression levels of nuclear transcription factor κB (NF-κB) and proinflammatory cytokines were also observed, suggesting that NF-κB might be required for the protracted induction of inflammatory genes. The corresponding changes in the mRNA levels of the inhibitor of κBα (IκBαa and IκBαb) may form a feedback loop to restore transcriptional activity of NF-κB. Furthermore, splenic ROS levels were increased by 5µg/L Cd, possibly activating NF-κB pathway. Taken together, immunosuppressive effects and tissue-dependent compensatory responses were demonstrated in zebrafish after full life-cycle exposure to environmental levels of Cd, indicating a compromise between survival and immunity.


Asunto(s)
Cadmio/toxicidad , Embrión no Mamífero/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Pez Cebra/inmunología , Animales , Citocinas/genética , Regulación hacia Abajo , Embrión no Mamífero/inmunología , Embrión no Mamífero/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , FN-kappa B/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Bazo/efectos de los fármacos , Bazo/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética
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