RESUMO
Nanoparticles, as a novel material, have a wide range of applications in the food and biomedical fields. Nanoparticles spontaneously adsorb proteins in the biological environment, and tens or even hundreds of proteins can form protein corona on the surface of nanoparticles. The formation of protein corona on the surface of nanoparticles is one of the key factors affecting the stability, biocompatibility, targeting, and drug release properties of nanoparticles. The formation mechanism of protein corona is affected by a variety of factors, including the surface chemical properties, sizes, and shapes of nanoparticles and the types, concentrations, and pH of proteins. Studies have shown that the protein structure is associated with protein distribution on the nanoparticle surface, while the protein conformation affects the binding mode and stability of the protein on the nanoparticle surface. Since the mechanism of the formation of protein corona on the surface of nanoparticles is complex, the roles of multiple factors need to be considered comprehensively. Understanding the mechanisms and influencing factors of the formation of protein corona will help us to understand the process of protein corona formation and control the formation of protein corona for specific needs. In this paper, we summarize the recent studies on the mechanisms and influencing factors of the formation of protein corona on the surface of nanoparticles, with a view to providing a theoretical basis for in-depth research on protein corona.
Assuntos
Nanopartículas , Coroa de Proteína , Propriedades de Superfície , Coroa de Proteína/química , Coroa de Proteína/metabolismo , Nanopartículas/química , Adsorção , Conformação Proteica , HumanosRESUMO
Deterioration of bread quality, characterized by the staling of bread crumb, the softening of bread crust and the loss of aroma, has caused a huge food waste and economic loss, which is a bottleneck restriction to the development of the breadmaking industry. Various bread improvers have been widely used to alleviate the issue. However, it is noteworthy that the sourdough technology has emerged as a pivotal factor in this regard. In sourdough, the metabolic breakdown of carbohydrates, proteins, and lipids leads to the production of exopolysaccharides, organic acids, aroma compounds, or prebiotics, which contributes to the preeminent ability of sourdough to enhance bread attributes. Moreover, sourdough exhibits a "green-label" feature, which satisfies the consumers' increasing demand for additive-free food products. In the past two decades, there has been a significant focus on sourdough with in situ produced dextran due to its exceptional performance. In this review, the behaviors of bread crucial compositions (i.e., starch and gluten) during dough mixing, proofing, baking and bread storing, as well as alterations induced by the acidic environment and the presence of dextran are systemically summarized. From the viewpoint of starch and gluten, results obtained confirm the synergistic amelioration on bread quality by the coadministration of acidity and dextran, and also highlight the central role of acidification. This review contributes to establishing a theoretical foundation for more effectively enhancing the quality of wheat breads through the application of in situ produced dextran.
Assuntos
Pão , Dextranos , Glutens , Amido , Triticum , Pão/análise , Pão/normas , Amido/química , Glutens/química , Dextranos/química , Triticum/química , Fermentação , Manipulação de Alimentos/métodos , Qualidade dos AlimentosRESUMO
Perfluorodecanoic acid (PFDA), an enduring and harmful organic pollutant, is widely employed in diverse food-related sectors. Our previous studies have provided evidence that PFDA has the potential to facilitate obesity and hepatic fat accumulation induced by high-fat diet (HFD) intake. Epigallocatechin-3-gallate (EGCG), a polyphenol found in green tea, has been suggested to possess potential preventive effects against metabolic abnormalities and fatty liver. The purpose of this research was to investigate the effects of EGCG on PFDA-exacerbated adiposity and hepatic lipid accumulation in HFD-fed mice. The results showed that EGCG reduced body weight gain; tissue and organ weights; blood glucose, serum insulin, HOMA-IR, leptin, and lipid parameters; serum inflammatory cytokines (IL-1ß, IL-18, IL-6, and TNF-α); and hepatic lipid accumulation in PFDA-exposed mice fed an HFD. Further work showed that EGCG improved liver function and glucose homeostasis in mice fed an HFD and co-exposed to PFDA. The elevated hepatic mRNA levels of SREBP-1 and associated lipogenic genes, NLRP3, and caspase-1 in PFDA-exposed mice fed an HFD were significantly decreased by EGCG. Our work provides evidence for the potential anti-obesity effect of EGCG on co-exposure to HFD and PFDA and may call for further research on the bioactivity of EGCG to attenuate the endocrine disruption effects of long-term exposure to pollutants.
Assuntos
Catequina , Dieta Hiperlipídica , Masculino , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Adiposidade , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/genética , Fígado , Ácidos Decanoicos/farmacologia , Catequina/farmacologia , Catequina/metabolismoRESUMO
An electrochemical sensor with high sensitivity for the detection of sodium nitrite was constructed based on the peroxidase-like activity of Au magnetic nanocomposites (Au@Fe3O4). The Au@Fe3O4 composite nanoparticles were green-synthesized via the reduction of gold nanoparticles (AuNPs) from waste chestnut skins combined with the sonochemical method. The nanoparticles have both the recoverability of Fe3O4 and the advantage of being able to amplify electrical signals. Furthermore, the synergistic effect of green reduction and sonochemical synthesis provides a functional approach for the preparation of Au@Fe3O4 with significant peroxidase-like activities. The physicochemical properties were characterized using transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), the Brunauer-Emmett-Teller (BET) method, and Fourier transform infrared spectroscopy (FT-IR). The electrochemical properties of sodium nitrite were determined with cyclic voltammetry (CV) and chronoamperometry (i-t). The results revealed that Au@Fe3O4 acted as a peroxidase mimic to decompose hydrogen peroxide to produce free radicals, while ·OH was the primary free radical that promoted the oxidation of sodium nitrite. With the optimal detection system, the constructed electrochemical sensor had a high sensitivity for sodium nitrite detection. In addition, the current response had a good linear relationship with the sodium nitrite concentration in the range of 0.01-100 mmol/L. The regression equation of the working curve was y = 1.0752x + 4.4728 (R2 = 0.9949), and the LOD was 0.867 µmol/L (S/N = 3). Meanwhile, the constructed detection system was outstanding in terms of recovery and anti-interference and had a good detection stability of more than 96.59%. The sensor has been successfully applied to a variety of real samples. In view of this, the proposed novel electrochemical analysis method has great prospects for application in the fields of food quality and environmental testing.
RESUMO
Perfluorodecanoic acid (PFDA), a chemical contaminant, may casue became obesity, which makes it a public health concern. In this study, we investigated the effects of PFDA on adiposity development and hepatic lipid accumulation in mice fed with a high-fat diet (HFD). Animals were assigned to two diet treatments (low-fat and high-fat); and PFDA was administered through drinking water for 12 weeks. The contaminant promoted body weight gain and adiposity in HFD-fed mice. Moreover, HFD-fed mice exposed to PFDA had impaired glucose metabolism, inflammation and hepatic lipid accumulation compared to mice fed HFD alone. PFDA activated the expression of hepatic NLRP3 and caspase-1, and induced that of SREBP-1c expression in the liver of HFD-fed mice. PFDA exposure in HFD-fed mice significantly inhibited hepatic AMPK expression than animals fed HFD without PFDA exposure. Furthermore, MCC950, an NLRP3 inhibitor, suppressed the upregulation of NLRP3 and caspase-1 expression, and inhibited the expression of SREBP-1c and the accumulation of hepatic lipid in mice exposed to PFDA. Thus, PFDA may enhance HFD-induced adiposity and hepatic lipid accumulation through the NLRP3/caspase-1 pathway. This contaminant may be a key risk factor for obesity development in individuals consuming high-fat foods, particularly Western diet.
Assuntos
Adiposidade , Proteína 3 que Contém Domínio de Pirina da Família NLR , Masculino , Camundongos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Dieta Hiperlipídica/efeitos adversos , Caspase 1/metabolismo , Camundongos Endogâmicos C57BL , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Metabolismo dos Lipídeos , Fígado , Obesidade/induzido quimicamente , Obesidade/metabolismo , Ácidos DecanoicosRESUMO
Using radix pueraria flavonoids (RPFs) as a reducing and stabilizing agent, we report a simple, cost-effective, and ecologically friendly green synthesis technique for gold nanoparticles (AuNPs) in the present study. Ultraviolet-visible (UV) spectroscopy, transmission electron microscopy (TEM), Fourier transform infrared (FTIR), and X-ray diffraction (XRD) investigations were used to characterize the AuNPs. The results demonstrated that the produced AuNPs were nearly spherical and that their particle sizes had a mean diameter of 4.85 ± 0.75 nm. The "Green" AuNPs, exhibiting remarkable peroxidase-like activity and Michaelis-Menten kinetics with high affinity for H2O2 and 3,3',5,5'-tetramethylbenzidine (TMB), were effectively applied to the fabrication of a sensitive nonenzymatic enhanced electrochemical sensor for the detection of cholesterol (Cho). Under optimum circumstances, it was possible to establish two linear ranges of 1-100 and 250-5000 µmol/L with a detection limit of 0.259 µmol/L (signal/noise ratio (S/N) = 3). The suggested sensor was utilized with satisfactory findings to determine the amount of Cho in food samples.
RESUMO
A free radical scavenging system based on Fe3O4@Au/MOF-ABTSË+ has formed the basis of a novel method for the highly sensitive and specific spectrophotometric determination of ascorbic acid (AA). The Fe3O4@Au/MOF nanozyme with magnetic separation properties was effectively prepared and evaluated using an environmentally friendly technique. Nanomaterials have the advantages of superparamagnetism, biocompatibility, chemical stability, and enhanced synergistic peroxidase-like activity, which can be utilized in catalysis to oxidise the peroxidase substrate 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) into a green-colored product in the presence of H2O2. AA as an antioxidant has scavenging effects on ABTS radicals and can reduce green ABTSË+ to uncolored ABTS2-, contributing to a substantial reduction in green color. Based on such a premise, a highly selective and sensitive chromogenic sensing method depending on the peroxidase-like activity of the nanocomposites was developed in order to achieve the efficient detection of AA in real samples. Under optimum conditions, the proposed technique had a detection range of 0.001-0.1 mmol L-1, a limit of detection of 0.098 µmol L-1, and a detection time of only 30 seconds. The newly proposed colorimetric analysis method devoid of enzymes has broad application potential in the areas of quality control and quality and safety detection.
Assuntos
Estruturas Metalorgânicas , Nanocompostos , Ácido Ascórbico , Antioxidantes , Colorimetria , Peróxido de Hidrogênio , PeroxidasesRESUMO
The intestinal microecological environment is critical to an infant's growth. For those infants consuming milk power, it is very important to improve the intestinal microecological environment to promote the healthy growth of infants. In this paper, Milk protein hydrolysate (MPH), consisting of different proportions of proteins and small molecule peptides (5:5, 4:6, 3:7, 2:8, 1:9) were added to infant formula powder (IFP). The effects of MFP-enriched IFP addition on proliferation and metabolism of Bifidobacterium L80 were studied. Compared with MPH-free IFP, MFP-enriched IFP with 1:9 of proteins to small molecule peptides significantly enhanced the proliferation of Bifidobacterium L80, resulting in higher cell density, greater viable counts and higher titratable acidity. MFP-enriched IFP increased the content of seven organic acids and H2O2 in the system, and improved the antibacterial activity to E. coli BL21. This study suggested that MPH could be an effective addition to infant formula powder to promote the growth of Bifidobacterium, so to improve the intestinal health of infants.
Assuntos
Bifidobacterium/crescimento & desenvolvimento , Bifidobacterium/metabolismo , Caseínas/metabolismo , Intestinos/microbiologia , Proteínas do Leite/metabolismo , Hidrolisados de Proteína/metabolismo , Proteínas do Soro do Leite/metabolismo , Animais , Caseínas/química , Humanos , Fórmulas Infantis/química , Proteínas do Leite/química , Hidrolisados de Proteína/química , Proteínas do Soro do Leite/químicaRESUMO
Casein nonphosphopeptide (CNPP), a byproduct formed during the preparation of casein phosphopeptide (CPP), is often discarded on a large scale. Although our previous studies have demonstrated the ameliorative effect of CNPP on muscle wasting disorders, its structure-function mechanism is still unclear. Therefore, considering the great influence of structural characteristics on function, this study aims to explain the potential mechanism by characterizing the physicochemical and functional properties of CNPP. The results of structural characterization indicated that CNPP was of low molecular weight and composed of the complete range of amino acids; it was particularly rich in leucine. Compared with casein, CNPP had a lower molecular size and total/free sulfhydryl content (reduced 2.44 and 2.02 µmol/g in CNPP, respectively). Additionally, Fourier transform infrared spectroscopic analysis revealed that enzymatic hydrolysis caused protein unfolding, and the content of ß-turns and random coils reached 50.20% and 10.67%, respectively. Fluorescence-dependent detection of CNPP indicated a reduction of spectral intensity and the occurrence of a red shift. The changes in the structure of CNPP significantly affected its functional characteristics. CNPP has better solubility, foaming, and digestion properties than those of casein and whey protein. Specifically, the foam stability and emulsification properties decreased in the order of casein > CNPP > whey protein. The present study can provide a substantial basis for future application of CNPP as a functional ingredient against sarcopenia.
Assuntos
Caseínas/química , Fosfopeptídeos/química , Aminoácidos/análise , Fenômenos Químicos , Emulsificantes/química , Indústria Alimentícia , Hidrólise , Leucina/análise , Peso Molecular , Estrutura Secundária de Proteína , Desdobramento de Proteína , Solubilidade , Resíduos , Proteínas do Soro do Leite/químicaRESUMO
Nowadays, more and more infants are getting allergic to cow's milk protein, so it is urgent to search for infant formula powder with milk protein alternatives. In the present work, soy protein hydrolysate (SPH) was added to protein-free infant formula powder and the effects of SPH addition on proliferation and metabolism of Streptococcus thermophilus were studied. Compared with commercially available infant formula powder (CK) and protein-free milk powder (BK), the infant formula powder with 20% SPH significantly enhanced the proliferation of S. thermophilus in MRS medium, resulting in a higher cell density and greater viable counts. Moreover, the influence of SPH on the metabolism of S. thermophilus was investigated by analyzing the content of seven organic acids and H2O2 in the medium. The higher content of organic acids and H2O2 is consistent with the stronger antibacterial activity to Escherichia coli. As a consequence, the addition of SPH to infant formula powder can effectively promote the growth of probiotics and SPH may be a promising protein alternative in the infant formula powder.
Assuntos
Fórmulas Infantis , Hipersensibilidade a Leite , Animais , Bovinos , Proliferação de Células , Feminino , Humanos , Peróxido de Hidrogênio , Lactente , Pós , Hidrolisados de Proteína , Streptococcus thermophilusRESUMO
The variations in flavor substances across the different stages of fermented soybean whey tofu (FSWT) production were analyzed by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) combined with principal component analysis (PCA). The results revealed 24 representative flavor compounds in the samples across all production stages. After heating, the signal intensity of hexanal, 1-octen-3-ol, heptanal, and (E)-2-hexenol, which are unpleasant flavor substances found in raw soymilk, weakened, whereas those of some aroma substances increased. Furthermore, fermented flavor compounds, namely, 2-heptanone, 2-pentylfuran, pentanal, and 2,3-butanedione, were produced after the addition of fermented soybean whey as a coagulant. A PCA based on the signal intensity of the detected volatile compounds revealed effective differentiation of samples from different stages into comparatively independent spaces. These results showed that the flavor fingerprints of the samples from different stages of FSWT production can be successfully built using HS-GC-IMS and PCA based on the detected volatile compounds.
Assuntos
Glycine max/química , Alimentos de Soja/análise , Compostos Orgânicos Voláteis/análise , Cromatografia Gasosa , Fermentação , Espectrometria de Mobilidade Iônica , Análise de Componente Principal , Glycine max/metabolismo , Compostos Orgânicos Voláteis/químicaRESUMO
Soy protein isolate hydrolysates (SPIH) were prepared from soy protein isolate (SPI). Effects of SPIH on a satiety signal cholecystokinin (CCK) and feeding behavior in rats were investigated. SPIH induced more CCK release (164.66 ± 2.40 pg/mL) by rat intestinal mucosal cells than SPI (143.33 ± 3.71 pg/mL). Meal size (MS), intermeal interval (IMI), and satiety ratio (SR = MS/IMI) of rats received different daily doses of SPIH or dietary fiber were detected for 40 days. A 100 mg/kg dose of SPIH resulted in a greater SR than an identical dose of dietary fiber, while a 300 mg/kg dose resulted in a less MS and IMI. A 500 mg/kg dose of SPIH had similar effects to the same dose of dietary fiber on reducing MS, extending IMI, and increasing SR, but resulted in a significantly less body weight at the end of the experiment (318.15 ± 17.83 g) than the dietary fiber group (340.28 ± 6.15 g).
RESUMO
Herein, Gold and magnetic particles (GoldMag), an enzyme mimetic of horseradish peroxidase (HRP), have been designed to construct a colorimetric sensor for cholesterol (Cho). The well-dispersed GoldMag was successfully prepared by green reduction using a self-assembly method based on the surface amino groups, and characterized by Fourier transform infrared (FTIR), X-Ray Photoelectron Spectroscopic (XPS) techniques. In the presence of H2O2, the resulting nanocomposites possessed enhanced intrinsic peroxidase-like activity and could catalytically oxidize 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) to produce a green colored product, which could be observed apparently by the naked eye. Based on the outstanding catalytic activity, the designed colorimetric sensor displayed a linear response for cholesterol in the range from 0.1 mg/mL to 7.5 mg/mL with a detection limit as low as 0.003 mg/mL. The proposed method was validated to determine cholesterol in real samples with satisfactory results.
Assuntos
Colorimetria , Nanocompostos , Colesterol , Peróxido de Hidrogênio , Peroxidase , PeroxidasesRESUMO
Manganese (Mn) can have adverse effects on organisms as a result of heavy or chronic exposure, including neurological damage. This study examined the effects of chronic exposure to manganese chloride (MnCl2) on various biochemical indices of inflammatory cytokines, antioxidant enzymes, and heat shock proteins (HSPs) in the kidneys of Hy-line cocks. The exposures were carried out using 600, 900, or 1800 mg/kg doses of MnCl2 administered for periods of 30, 60, and 90 days. The exposure experiments indicated that Mn concentration in the kidneys increased over time and that Mn exposure potentially caused ultrastructural changes to the cells. Treatment with Mn was seen to increase the levels of various biomarkers, including protein carbonyl group content; DNA-protein cross-links (DPCs) and the mRNA expression of inflammatory factors such as tumor necrosis factor-α (TNF-α), nuclear factor-κB p50 (NF-κB p50), cyclooxygenase-2 (COX-2), and prostaglandin E synthase (PGES). The levels of other biomarkers were found to decrease as a result of Mn exposure, including the mRNA expression of oxidation indexes such as copper-zinc superoxide dismutase (CuZn-SOD), manganese superoxide dismutase (Mn-SOD), glutathione peroxidase (GSH-Px), and catalase (CAT). Accompanying the above changes, Mn exposure was seen to result in the relative mRNA and protein expression of HSPs 90, 70, 60, 40, and 27 increasing significantly. Thus, in cock kidneys, HSPs attenuated the biological changes caused by toxic exposure to Mn. This mechanism needs further exploration.
Assuntos
Proteínas de Choque Térmico , Manganês , Animais , Galinhas/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Rim/metabolismo , Manganês/toxicidade , Estresse Oxidativo , Superóxido Dismutase/metabolismoRESUMO
A new scheme for sensitive and rapid colorimetric detection of ascorbic acid (AA) has been developed by the GoldMag-ABTS free radical scavenging system. The well-dispersed Gold and magnetic particles (GoldMag) was successfully prepared by self-assembly method and characterized by Fourier transform infrared (FTIR), X-Ray Photoelectron Spectroscopic (XPS) techniques. Nanocomposites combine the advantages of superparamagnetic, biocompatibility and high catalytic activity of Fe3O4 and gold nanoparticles (AuNPs) and exhibit enhanced the intrinsic peroxidase-like activity, which can be used to catalyze the oxidation of the peroxidase substrates 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) produce a green-colored product in presence of hydrogen peroxide. Ascorbic acid as an effective antioxidant have scavenging effects on ABTS radicals and induce the reduction of green ABTS.+ to colorless ABTS2-, resulting in a significant green color fading. On this basis, a rapid, sensitive and selective colorimetric assay for ascorbic acid has been developed. Under optimal conditions, ascorbic acid has a linear response range from 0.01â¯mmol/L to 1â¯mmol/L with a detection limit of 0.12⯵mol/L and a short assay time of the 30â¯s. Furthermore, the colorimetric system showed good sensitivity, stability, selectivity, and repeatability. It also successfully applied to the determination of ascorbic acid in real samples.
Assuntos
Ácido Ascórbico/análise , Ouro/química , Nanopartículas de Magnetita/química , Nanopartículas Metálicas/química , Vitaminas/análise , Materiais Biomiméticos/química , Catálise , Colorimetria/métodos , Nanocompostos/química , Peroxidase/química , ComprimidosRESUMO
The effects of casein non-phosphopeptide (CNPP) on the muscle development of healthy rats and selected blood hormones levels were investigated. CT technology and the ELISA kit were employed to detect the cross-sectional area of each muscle group and blood hormone levels, respectively. The cross-sectional area of the trunk and lower limb muscles of resistance exercise group (REG) rats that were administered a high daily dose of CNPP for 50 days increased more significantly than that of the blank group rats, no exercise group (NEG) rats administered with the same daily dose of CNPP, and REG rats administered with the same daily dose of lactalbumin (P < 0.05).The more enhanced development of trunk and lower limb muscles in CNPP-administered REG rats was associated with a higher blood level of insulin, while no clear trends in blood levels of growth hormone and testosterone were observed. The present results have demonstrated that a combination of physical exercise and diet supplementation with CNPP can synergistically improve muscle mass.
Assuntos
Caseínas/farmacologia , Músculo Esquelético/efeitos dos fármacos , Condicionamento Físico Animal , Tomógrafos Computadorizados , Animais , Hormônio do Crescimento/sangue , Concentração de Íons de Hidrogênio , Insulina/sangue , Lactalbumina/sangue , Leucina/farmacologia , Masculino , Desenvolvimento Muscular/efeitos dos fármacos , Músculo Esquelético/crescimento & desenvolvimento , Ratos , Ratos Wistar , Testosterona/sangueRESUMO
A simple and sensitive method for colorimetric detection of mercury ion (Hg(2+)) has been developed by using a poly (γ-glutamic acid) functionalized gold nanoparticles (PGA-AuNPs) system. Electrostatic self-assembly technique was used to assemble negatively charged PGA on the surface of positively charged CTAB-capped AuNPs. With the increase of Hg(2+) concentration, the color of the solution would progress from light red to purple blue. The results showed that the absorbance ratio (A750/A580) was linear with the Hg(2+) concentration in the range of 0.01-10 µM and from 50 to 300 µM, with the correlation coefficients of 0.998 and 0.991, respectively. The reported probe is suitable for real-time detection of Hg(2+) in water with the limit of detection (LOD) of 1.9 nM obtained by UV-vis spectrum, and exhibits selectivity toward one order of magnitude over other metal ions. This approach was applied successfully to the determination of Hg(2+) in tap water and mineral water, and the recoveries were from 90% to 103% and from 103.53% to 113%, respectively. The proposed method is rapid, low-cost and free of complex equipment, making it possible to analyze Hg(2+) in various water samples.
Assuntos
Técnicas Biossensoriais/métodos , Colorimetria/métodos , Ouro/química , Mercúrio/análise , Nanopartículas Metálicas/química , Ácido Poliglutâmico/análogos & derivados , Íons , Nanopartículas Metálicas/ultraestrutura , Ácido Poliglutâmico/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Água/químicaRESUMO
Manganese (Mn) is a trace element known to be essential for maintaining the proper function and regulation of many biochemical and cellular reactions. However, little is known about the reproductive toxicity of Mn in birds. To investigate the toxicity of Mn on male reproduction in birds, 50-day-old cocks were fed either a commercial diet or a Mn-supplemented diet containing 600, 900, and 1800 mg/kg MnCl2. After being treated with Mn for 30, 60, and 90 d, the following were determined: Mn content; histological and ultrastructural changes in the testes, apoptosis; the malondialdehyde (MDA) level; the activities of superoxide dismutase (SOD); the inhibition ability of hydroxyl radicals (OH); the levels of nitric oxide (NO), nitric oxide synthase (NOS), and protein carbonyl in the testes; the DNA-protein crosslinks (DPC); and the activity of the ATP enzyme. Exposure to Mn significantly lowered the activity of SOD and glutathione peroxidase (GPx) and the inhibition ability of OH. Mn exposure also increased the levels of MDA, NO, NOS, DPC, and protein carbonyl; the number of apoptotic cells; and the Mn content and caused obvious histopathological changes in the testes. These findings suggested that Mn exposure resulted in the oxidative damage of cock testicular tissue by altering radical formation, ATP enzyme systems, apoptosis, and DNA damage, which are possible underlying reproductive toxicity mechanisms induced by Mn exposure.
Assuntos
Apoptose/efeitos dos fármacos , Suplementos Nutricionais , Manganês/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Antioxidantes/metabolismo , Galinhas , Cloretos/administração & dosagem , Cloretos/toxicidade , Dano ao DNA/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Radical Hidroxila/metabolismo , Masculino , Malondialdeído/metabolismo , Manganês/administração & dosagem , Compostos de Manganês/administração & dosagem , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Carbonilação Proteica/efeitos dos fármacos , Reprodução/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Testículo/patologiaRESUMO
Exposure to Manganese (Mn) is a common phenomenon due to its environmental pervasiveness. To investigate the Mn-induced toxicity on cerebral trace element levels and crucial nitric oxide parameters on brain of birds, 50-day-old male Hyline cocks were fed either a commercial diet or a Mn-supplemented diet containing 600, 900, 1,800 mg kg(-1). After being treated with Mn for 30, 60, and 90 days, the following were determined: the changes in contents of copper (Cu), iron (Fe), zinc (Zn), calcium (Ca), selenium (Se) in brain; inducible nitric oxide synthase-nitric oxide (iNOS-NO) system activity in brain; and histopathology and ultrastructure changes of cerebral cortex. The results showed that Mn was accumulated in brain and the content of Cu and Fe increased. However, the levels of Zn and Se decreased and the Ca content presented no obvious regularity. Exposure to Mn significantly elevated the content of NO and the expression of iNOS mRNA. Activity of total NO synthase (T NOS) and iNOS appeared with an increased tendency. These findings suggested that Mn exposure resulted in the imbalance of cerebral trace elements and influenced iNOS in the molecular level, which are possible underlying nervous system injury mechanisms induced by Mn exposure.
Assuntos
Química Encefálica/efeitos dos fármacos , Encéfalo/metabolismo , Manganês/farmacologia , Óxido Nítrico/metabolismo , Oligoelementos/metabolismo , Animais , Proteínas Aviárias/metabolismo , Galinhas , Masculino , Proteínas do Tecido Nervoso/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismoRESUMO
Stable and even microcrystals of Avermectin (AVM) were produced by recrystallization in presence of a stabilizer. Sequential layer growth was achieved by the layer-by-layer (LbL) self-assembly of biocompatible polyelectrolytes (PEs). The coated colloids were characterized using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). The in vitro release of Avermectin from microcapsules was studied under the simulated insect midgut conditions. W-doped TiO(2) photocatalysts were synthesized by a simple hydrothermal method, and characterized by Brunauer-Emmett-Teller (BET) surface area measurements and SEM. The photocatalytic activities of photocatalysts, which were undoped with TiO(2) and W-doped TiO(2), were evaluated by the photocatalytic oxidation degradation of AVM microcapsules in aqueous solution under UV illumination. The toxicity of the photodegradable insecticide was evaluated by the adult stage Martianus dermestoides. The results showed that AVM microcrystals which were obtained by association had a mean length of 13.8µm and a zeta potential of -34.7mV. The drug loading and encapsulation efficiency were 65.57±0.96% and 46.15±0.96%, respectively. The in vitro release experiments revealed that the polyelectrolytes prolonged the release time of the encapsulated AVM microcrystals. The sample which was prepared at 120°C with 4.0mol% W-doped amount had the highest photocatalytic activity. Toxicity of the novel photodegradable insecticide was higher in the adult stage compared to the 95% AVM as indicated by the lower LC(50) value.