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1.
Food Chem ; 315: 126207, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31991252

RESUMO

Five major proteins from egg white were separated using a successive extraction/precipitation protocol. The yield and purity of the separated proteins were measured. The separated proteins were confirmed by MALDI-TOF-MS, and their structures were characterized by CD spectrum. Lysozyme was first separated using FPC 3500 resin and then ovomucin from the lysozyme-free egg white. Ammonium sulfate and citric acid were added to the resulting lysozyme- and ovomucin-free egg white solution to precipitate ovotransferrin. Ovomucoid and ovalbumin were separated from the resulting supernatant using ethanol. The separated proteins were further purified and the optimal conditions for the further purifications were suggested. The purity and yield of lysozyme, ovotransferrin, ovalbumin, and ovomucoid were higher than 90% and 77%, while those of ovomucin were about 72% and 75%, respectively. This study separated five major proteins in egg white successively using resin adsorption, pH adjustment, salt/ethanol precipitation, and ultrafiltration.


Assuntos
Fracionamento Químico/métodos , Proteínas do Ovo/análise , Proteínas do Ovo/isolamento & purificação , Clara de Ovo/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sulfato de Amônio/química , Animais , Precipitação Química , Conalbumina/análise , Conalbumina/isolamento & purificação , Proteínas do Ovo/química , Clara de Ovo/análise , Etanol/química , Muramidase/análise , Muramidase/isolamento & purificação , Ovalbumina/análise , Ovalbumina/isolamento & purificação , Ovomucina/análise , Ovomucina/isolamento & purificação , Estrutura Secundária de Proteína
2.
Anal Chim Acta ; 1097: 161-168, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31910956

RESUMO

A new adsorbent based on pH-responsive polymer assisted aptamer functionalized magnetic nanoparticles was developed for specific recognition and efficient adsorption of proteins. Arising from the synergistic effect of specific affinity of apatamer on protein and tunable hydrophobic/hydrophilic property of pH-responsive polymer, the adsorbent exhibited excellent adsorption capacity for target protein. Notably, because of the pH-responsive property of the polymer, the adsorption and desorption process could be regulated through varying environmental pH. The resultant adsorbent that immobilized with lysozyme binding aptamer was successfully applied in specific recognition and efficient adsorption of lysozyme in egg white samples and good recovery results in the range of 95.2-103.2% were obtained. Moreover, the adsorbent immobilized with cytochrome C binding aptamer also exhibited satisfactory adsorption to cytochrome C. The synergistic effect of pH-responsive polymer and aptamer promoted the recognition selectivity and adsorption capacity to target protein, illustrating a facile way for construction of more specific protein adsorbents.


Assuntos
Aptâmeros de Nucleotídeos/química , Nanopartículas de Magnetita/química , Polímeros/química , Adsorção , Conalbumina/análise , Citocromos c/análise , Citocromos c/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Muramidase/análise , Muramidase/metabolismo , Pepsina A/análise , Pepsina A/metabolismo , Albumina Sérica Humana/análise , Tripsina/análise , Tripsina/metabolismo
3.
Food Chem ; 305: 125453, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505417

RESUMO

Impact of glycerol and sorbitol on assembly of iron-bound ovotransferrin (OVT) into nanofibrils was investigated. Thioflavin T fluorescence result indicated that the presence of glycerol or sorbitol could reduce the rate of OVT fibrillation. Sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated that 60% sorbitol could retard hydrolysis of OVT completely for a period of time during thermal treatment, and decoupling hydrolysis from fibril self-assembly helped to identify the building blocks of OVT nanofibrils. OVT nanofibrils were composed of both intact OVT monomers and OVT-derived peptides. Influence of glycerol and sorbitol on morphology of OVT nanofibrils was studied using atomic force microscopy. The presence of glycerol or sorbitol shortened OVT nanofibrils, and the presence of 60% glycerol or sorbitol could increase thickness of OVT nanofibrils. Hopefully, this work may provide new insight about building blocks of protein nanofibrils and impact of polyols on protein fibrillation.


Assuntos
Conalbumina/química , Glicerol/química , Nanoestruturas/química , Sorbitol/química , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Propriedades de Superfície
4.
Molecules ; 24(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775281

RESUMO

Gut health is the starting place for maintaining the overall health of an animal. Strategies to maintain gut health are, thus, an important part in achieving the goal of improving animal health. A new strategy to do this involves two molecules: the iron transport protein ovotransferrin (IT) and α-tocopheryl polyethylene glycol succinate (TPGS), which result in the novel formulation of ITPGS. These molecules help reduce gut pathogens, while enhancing the absorption and bioavailability of therapeutic drugs, phytomedicines, and nanomedicines. This, in turn, helps to maintain normal health in animals. Maintaining the gastrointestinal tract (GIT) in its normal condition is key for successful absorption and efficacy of any nutrient. A compromised GIT, due to an imbalance (dysbiosis) in the GIT microbiome, can lead to an impaired GI barrier system with impaired absorption and overall health of the animal. The molecules in ITPGS may address the issue of poor absorption by keeping the GI system healthy by maintaining the normal microbiome and improving the absorption of nutrients through multiple mechanisms involving antioxidative, anti-inflammatory, immunomodulatory, and antimicrobial activities. The ITPGS technology can allow the dose of active pharmaceutical or herbal medicine to be significantly reduced in order to attain equal or better efficacy. With complimentary actions between IT and TPGS, ITPGS presents a novel approach to increase the bioavailability of drugs, phytoconstituents, nutrients, and nanomedicines by enhanced transport to the tissues at the site of action, while reducing gut pathogen load. The ITPGS approach appears to be a novel strategy for maintaining the health of animals by manipulation of microbiota.


Assuntos
Conalbumina/farmacologia , Trato Gastrointestinal/efeitos dos fármacos , Gastropatias/tratamento farmacológico , Vitamina E/farmacologia , Animais , Disponibilidade Biológica , Conalbumina/química , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Trato Gastrointestinal/microbiologia , Ferro/metabolismo , Gastropatias/veterinária , Vitamina E/química
5.
Nutrients ; 11(9)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546863

RESUMO

Ovotransferrin, a member of the transferrin family, is the second main protein found in egg white. Ovotransferrin was reported to have antimicrobial, antioxidant, and immunomodulating activities. The aim of this work was to characterize the cellular and molecular functions of egg white ovotransferrin on osteoclasts differentiation and function. Osteoclasts were prepared from mouse macrophage RAW 264.7 cells stimulated with receptor activator of nuclear factor κB ligand (RANKL). Ovotransferrin inhibited osteoclasts differentiation and the calcium-phosphate resorptive ability via the suppression of RANKL-induced nuclear factor κ-light chain-enhancer of activated B cells (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Ovotransferrin induced apoptosis of matured osteoclasts, accompanied by increased expression of Bcl-2-like protein 11 (Bim) and Bcl-2-assoicated death promoter (Bad), but decreased expression of B-cell lymphoma 2 (Bcl-2) and B-cell lymphoma-extra-large (Bcl-xl). We established a novel role of egg white ovotransferrin as an inhibitor of osteoclastogenesis, which may be used for the prevention of osteoporosis.


Assuntos
Reabsorção Óssea/metabolismo , Conalbumina/farmacologia , Clara de Ovo/química , Osteoclastos/efeitos dos fármacos , Ligante RANK/metabolismo , Animais , Apoptose , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Osteoclastos/fisiologia , Ligante RANK/genética , Células RAW 264.7
6.
J Agric Food Chem ; 67(35): 9907-9915, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31436102

RESUMO

The impact of covalent or non-covalent bound gallic acid (GA) on the formation, physicochemical properties, and digestion of ovotransferrin (OTF) nanofibrils was comprehensively studied. Thioflavin T fluorescence results revealed that bound GA could inhibit OTF nanofibrillation and that the fibril-inhibitory activity of bound GA was dose dependent. Covalent bound GA exerted stronger inhibition on OTF nanofibrillation than an equal amount of non-covalent bound GA. Atomic force microscopy revealed that covalent bound GA shortened OTF nanofibrils significantly, while non-covalent bound GA did not change the contour length of OTF fibrils remarkably. Bound GA altered diameter of OTF nanofibrils. Both covalent and non-covalent bound GA could alter the zeta potential, surface hydrophobicity, and rheological properties of OTF nanofibrils. Bound GA endowed OTF nanofibrils with a strong antioxidant activity. In vitro gastrointestinal digestion results showed that covalent bound GA elevated the fibril digestion rate better than non-covalent bound GA. Polyphenol binding provided a new approach to modulating the physicochemical properties of protein nanofibrils.


Assuntos
Conalbumina/química , Ácido Gálico/química , Nanofibras/química , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Galinhas , Conalbumina/metabolismo , Digestão , Ácido Gálico/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Modelos Biológicos , Reologia
7.
Food Funct ; 10(8): 4911-4923, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31342040

RESUMO

The present work aimed to fabricate antioxidant particle-stabilized Pickering emulsions with outstanding protection of encapsulated nutraceuticals. Antioxidant ovotransferrin-gallic acid conjugates (OTGCONJ) were prepared using the alkaline method, and the electrostatic assembly technique was utilized to construct OTGCONJ-CMD particles with OTGCONJ and carboxymethyldextran (CMD) as the building blocks. After the investigation of the particle size, insoluble nature and intermediate wettability of the OTGCONJ-CMD particles, the OTGCONJ-CMD particles were verified as eligible Pickering stabilizers. Visual observation showed that the stable OTGCONJ-CMD particle-stabilized Pickering emulsion consisted of the emulsified phase alone. Rheological analysis revealed that the Pickering emulsion had a high viscosity and a gel-like structure. In terms of the protective effect, the OTGCONJ-CMD particle-stabilized Pickering emulsion could significantly retard curcumin degradation under UV light. An in vitro digestion study revealed that the OTGCONJ-CMD particle-stabilized Pickering emulsion improved both the extent of lipolysis and curcumin bioaccessibility remarkably, suggesting that the OTGCONJ-CMD particle-stabilized Pickering emulsion was an excellent nutraceutical delivery vehicle. The novel findings in this work could have important implications for the design of nutraceutical-loaded Pickering emulsions with an excellent protective effect and nutraceutical delivery efficiency.


Assuntos
Conalbumina/química , Curcumina/química , Fixadores/química , Ácido Gálico/química , Antioxidantes/química , Dextranos , Emulsões/química , Tamanho da Partícula
8.
J Exp Biol ; 222(Pt 6)2019 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-30814292

RESUMO

Avian eggs contend with omnipresent microorganisms entering the egg interior, where they affect embryo viability and hatchling phenotype. The incubation behaviour and deposition of egg white antimicrobial proteins (AMPs) vary highly across the avian altricial-precocial spectrum. Experimental evidence of how these alterations in avian reproductive strategies affect the antimicrobial properties of the precocial and altricial egg interior is lacking, however. Here, we tested the egg white antimicrobial activity in eggs of two representative model species, from each end of the avian altricial-precocial spectrum, against potentially pathogenic and beneficial probiotic microorganisms. Eggs were experimentally treated to mimic un-incubated eggs in the nest, partial incubation during the egg-laying period, the onset of full incubation and the increased deposition of two main egg white AMPs, lysozyme and ovotransferrin. We moreover assessed to what extent egg antimicrobial components, egg white pH and AMP concentrations varied as a result of different incubation patterns. Fully incubated precocial and altricial eggs decreased their antimicrobial activity against a potentially pathogenic microorganism, whereas partial incubation significantly enhanced the persistence of a beneficial probiotic microorganism in precocial eggs. These effects were most probably conditioned by temperature-dependent alterations in egg white pH and AMP concentrations. While lysozyme concentration and pH decreased in fully incubated precocial but not altricial eggs, egg white ovotransferrin increased along with the intensity of incubation in both precocial and altricial eggs. This study is the first to experimentally demonstrate that different incubation patterns may have selective antimicrobial potential mediated by species-specific effects on antimicrobial components in the egg white.


Assuntos
Anti-Infecciosos/farmacologia , Proteínas Aviárias/farmacologia , Columbidae/fisiologia , Conalbumina/farmacologia , Coturnix/fisiologia , Clara de Ovo/química , Reprodução , Animais , Bacillus subtilis/efeitos dos fármacos , Micrococcus luteus/efeitos dos fármacos , Muramidase/farmacologia , Óvulo/enzimologia , Óvulo/fisiologia
9.
Food Funct ; 10(2): 1109-1122, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30724290

RESUMO

In this study, the regulative effects of ovotransferrin (OVT) on immunomodulatory function and intestinal microbial dysbiosis in a mouse model injected with cyclophosphamide (CP) were investigated. The immunomodulatory effect of OVT was determined by enzyme-linked immune sorbent assay (ELISA). Gut microbial composition was determined by high-throughput sequencing of the V3-V4 region of the 16S rDNA gene. The changes in the relative abundance of the dominant microbiota were analyzed at different taxonomic levels. The results showed that OVT alleviated the immune dysfunction caused by CP. OVT improved the spleen and thymus indices and enhanced the secretion of tumor necrosis factor alpha (TNF-α), interleukin-10 (IL-10), and immunoglobulin A (IgA). In addition, OVT increased the indexes of Shannon and Simpson, suggesting the enhancement of the diversity and richness of intestinal microflora. The relative abundance of Lachnospiraceae_NK4A136_group was also increased. However, the relative abundance of Helicobacter and Desulfovibrio was significantly decreased. These results indicated that OVT, a food-derived functional component, has effects on immune regulation in the organism and ameliorates the gut microbiota disorders induced by CP, which provides a potential therapeutic utilization of avian eggs by targeting the gut microbiome.


Assuntos
Conalbumina/farmacologia , Ciclofosfamida/toxicidade , Disbiose/tratamento farmacológico , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , DNA Bacteriano , Feminino , Genoma Bacteriano , Imunossupressores/toxicidade , Camundongos , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Organismos Livres de Patógenos Específicos
10.
Biomed Res Int ; 2019: 8676410, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719449

RESUMO

IRW (Ile-Arg-Trp), a bioactive peptide isolated from egg ovotransferrin, has been shown to exert anti-inflammatory effects. In this study, the effects of IRW on inflammatory cytokines and microbiota were explored in human umbilical vein endothelial cells (HUVECs) and a lipopolysaccharide (LPS)-induced rat model of inflammatory peritonitis. Rats were injected intraperitoneally with LPS to establish peritonitis. HUVECs were exposed to IRW for 12 h before introducing LPS. Notably, IRW exerted beneficial effects against LPS-induced peritonitis, specifically, by reducing the serum levels of tumour necrosis factor (TNF)-α and interleukin (IL)-6 and myeloperoxidase (MPO) activity (P<0.05). A faecal microbiota analysis revealed that IRW significantly increased the Shannon and decreased the Simpson indices (P<0.05). Furthermore, IRW treatment significantly inhibited the LPS-induced enhancement of TNF-α, IL-8, intercellular cell adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) expression in HUVECs (P<0.05). In conclusion, IRW supplementation inhibited the inflammatory mediator synthesis and LPS-induced inflammatory responses and influenced the gut microbiota.


Assuntos
Anti-Inflamatórios/farmacologia , Conalbumina/farmacologia , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Lipopolissacarídeos/farmacologia , Peptídeos/farmacologia , Animais , Linhagem Celular , Citocinas/metabolismo , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Inflamação/metabolismo , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Peritonite , Peroxidase/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
11.
Transgenic Res ; 28(1): 51-76, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30374651

RESUMO

Zoonotic and foodborne diseases pose a significant burden, decreasing both human and animal health. Modifying chickens to overexpress antimicrobials has the potential to decrease bacterial growth on poultry products and boost chicken innate immunity. Chickens overexpressing either ovotransferrin or avian ß-defensin-3 (AvßD3) were generated using Tol-2 transposons. Transgene expression at the RNA and protein level was seen in egg white, breast muscle, and serum. There were significant differences in the immune cell populations in the blood, bursa, and spleen associated with transgene expression including an increased proportion of CD8+ cells in the blood of ovotransferrin and AvßD3 transgenic birds. Expression of the antimicrobials inhibited the in vitro growth of human and chicken bacterial pathogens and spoilage bacteria. For example, transgene expression significantly reduced growth of aerobic and coliform bacteria in breast muscle and decreased the growth of Salmonella enterica in egg white. Overall these results indicate that overexpression of antimicrobials in the chicken can impact the immune system and increase the antimicrobial capacity of poultry products.


Assuntos
Animais Geneticamente Modificados/genética , Conalbumina/genética , Imunidade Inata/genética , beta-Defensinas/genética , Animais , Animais Geneticamente Modificados/microbiologia , Anti-Infecciosos/sangue , Galinhas/sangue , Galinhas/genética , Conalbumina/sangue , Conalbumina/imunologia , Elementos de DNA Transponíveis/genética , Clara de Ovo/química , Regulação da Expressão Gênica/genética , Humanos , Músculos/metabolismo , Produtos Avícolas/microbiologia , beta-Defensinas/sangue , beta-Defensinas/imunologia
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 208: 243-254, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30342339

RESUMO

Due to the high sensitivity to alterations in microenvironment polarity of macromolecules, pyrene and its derivatives have long been applied in biosciences. Human serum albumin (HSA), besides its numerous physiological functions, is the main responsible by transport of endogenous and exogenous compounds in the circulatory system. Here, a comprehensive study was carry out to understand the interaction between HSA and the pyrene derivative 1-pyrenesulfonic acid (PMS), which showed a singular behaviour when bound to this protein. The complexation of PMS with HSA was studied by steady state, time-resolved and anisotropy fluorescence, induction of circular dichroism (ICD) and molecular docking. The fluorescence quenching of PMS by HSA was abnormal, being stronger at lower concentration of the quencher. Similar behaviour was obtained by measuring the ICD signal and fluorescence lifetime of PMS complexed in HSA. The displacement of PMS by site-specific drugs showed that this probe occupied both sites, but with higher affinity for site II. The movement of PMS between these main binding sites was responsible by the abnormal effect. Using the holo (PDB: ID 1A06) and apo (PDB: ID 1E7A) HSA structures, the experimental results were corroborated by molecular docking simulation. The abnormal spectroscopic behaviour of PMS is related to its binding in different regions in the protein. The movement of PMS into the protein can be traced by alteration in the spectroscopic signals. These findings bring a new point of view about the use of fluorescence quenching to characterize the interaction between albumin and ligands.


Assuntos
Conalbumina/metabolismo , Pirenos/metabolismo , Soroalbumina Bovina/metabolismo , Albumina Sérica Humana/metabolismo , Ácidos Sulfônicos/metabolismo , Animais , Anisotropia , Sítios de Ligação , Bovinos , Dicroísmo Circular , Fluorescência , Humanos , Simulação de Acoplamento Molecular , Pirenos/química , Ácidos Sulfônicos/química , Termodinâmica , Fatores de Tempo , Triptofano/análogos & derivados , Triptofano/química
13.
J Microbiol Methods ; 154: 19-24, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30291881

RESUMO

The purpose of this study was to establish a method for determining the bacteriolytic activity after separation of lysozyme-binding proteins from egg white. Lysozyme-binding proteins such as ovotransferrin and ovalbumin were separated by non-denaturing two-dimensional electrophoresis (2DE) and transferred to a membrane. The lysozyme activity of the separated and immobilized egg white proteins was assessed directly to produce a non-denaturing 3D map of the egg white proteins by incorporating an axis that combined each spot's lysozyme-activity with the non-denaturing 2DE pattern. Lysozyme-ovotransferrin and lysozyme-ovalbumin complexes could be reconstructed in vitro after the cathode end fraction containing lysozyme was added to purified ovotransferrin and ovalbumin, respectively. These complexes retained lysozyme activity even after separation by non-denaturing 2DE. Furthermore, when the lysozyme-ovotransferrin complex from egg white was extracted after separation by isoelectric focusing by replacing the cathodic sodium hydroxide solution with phosphoric acid solution, the complex possessed bacteriolytic activity against both Bacillus subtilis and Escherichia coli. These methods can be applied to investigate protein complexes possessing bacteriolytic activity against a wide range of both Gram-positive and Gram-negative bacteria.


Assuntos
Antibacterianos/farmacologia , Proteínas de Transporte/farmacologia , Galinhas , Proteínas do Ovo/química , Proteínas do Ovo/isolamento & purificação , Muramidase/farmacologia , Animais , Compostos Azo/química , Bacillus subtilis/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bacteriólise , Conalbumina/química , Conalbumina/farmacologia , Eletroforese em Gel Bidimensional/métodos , Escherichia coli/efeitos dos fármacos , Imobilização , Focalização Isoelétrica/métodos , Muramidase/química , Ovalbumina/química , Ovalbumina/farmacologia
14.
Int J Biol Macromol ; 120(Pt A): 1-9, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30114420

RESUMO

Ovotransferrin (OVT), a glycoprotein from avian egg, which has a variety of biological activities and immunomodulatory effects. The purpose of this research was to demonstrate the effect of OVT on intestinal immunomodulatory function which used a mouse model of cyclophosphamide (CP) induced intestinal immunosuppression and injury by intraperitoneal injection of 80 mg/kg. Effects of OVT on intestinal immunomodulatory function in CP-induced immunosuppression mice were detected by flow cytometry, real-time quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and western blot. Results showed that OVT effectively increased the major histocompatibility complex class II (MHC-II) and cluster of differentiation 83 (CD83) levels to enhance intestinal dendritic cells (DCs) maturation and promoted the expression of cytokines and gene of tumor necrosis factor alpha (TNF-α), interferon-γ (IFN-γ), interleukin-4 (IL-4) and interleukin-10 (IL-10). Furthermore, the imbalance ratio of the Th1 and Th2 in the intestine was regulated to produce an immune response and the expression of immunoglobulin A (IgA) and secretory immunoglobulin A (sIgA) were increased to promote humoral immunity by OVT-treated. Meanwhile, cyclophosphamide treatment induces activation of p38 MAPK, c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) to causes intestinal damage and blockage of p38 MAPK, JNK and ERK activation contributed to the effect of OVT on the repair of intestinal damage. These results indicated that OVT may have immunomodulatory function and could be potential functional factor to regulate body intestinal immunity.


Assuntos
Conalbumina/farmacologia , Ciclofosfamida/farmacologia , Imunossupressão , Intestinos/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Animais , Antígenos CD/imunologia , Conalbumina/imunologia , Citocinas/imunologia , MAP Quinases Reguladas por Sinal Extracelular/imunologia , Feminino , Antígenos de Histocompatibilidade Classe II/imunologia , Imunoglobulina A Secretora/imunologia , Imunoglobulinas/imunologia , Intestinos/patologia , Sistema de Sinalização das MAP Quinases/imunologia , Glicoproteínas de Membrana/imunologia , Camundongos
15.
Vet Res ; 49(1): 51, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29925427

RESUMO

Intestinal health is critically important for the welfare and performance of poultry. Enteric diseases that cause gut barrier failure result in high economic losses. Up till now there is no reliable faecal marker to measure gut barrier failure under field conditions. Therefore, the aim of the present study was to identify a faecal protein marker for diminished intestinal barrier function due to enteric diseases in broilers. To assess this, experimental necrotic enteritis and coccidiosis in broilers were used as models for gut barrier failure. Ovotransferrin was identified as a marker for gut barrier failure using a proteomics approach on samples from chickens with necrotic enteritis. These results were confirmed via ELISA on samples derived from both necrotic enteritis and coccidiosis trials, where faecal ovotransferrin levels were significantly correlated with the severity of gut barrier failure caused by either coccidiosis or necrotic enteritis. This indicates that faecal ovotransferrin quantification may represent a valuable tool to measure gut barrier failure caused by enteric pathogens.


Assuntos
Proteínas Aviárias/metabolismo , Galinhas/fisiologia , Coccidiose/veterinária , Conalbumina/metabolismo , Enterite/veterinária , Fezes/química , Intestinos/fisiopatologia , Animais , Coccidiose/fisiopatologia , Enterite/fisiopatologia , Ensaio de Imunoadsorção Enzimática/veterinária , Proteômica
16.
Food Chem ; 263: 135-141, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784298

RESUMO

Egg white thinning during ambient storage is a well-known phenomenon. The objective of the study was to characterize the formation of peptides <10 kDa in egg white during storage at room temperature. The results indicated that the content of peptides in the egg white fraction of <10 kDa increased gradually. Similar but a faster trend was observed for the fraction of <3 kDa. Gallin, also called ovodefensin (∼7 kDa), was the main component in 10-3 kDa egg white fraction, which rapidly degraded and disappeared at 28 d of storage. Mass spectrometry analysis of <3 kDa fraction identified 6 peptide fragments from ovotransferrin and 11 peptides from ovomucin. Ovodefensin, ovotransferrin and ovomucin are the major innate components of egg defense; thus the degradation of these proteins during storage contributes to egg white thinning and increased susceptibility to bacterial contamination. This study provides the insights on the molecular mechanism of egg deterioration during prolonged ambient storage.


Assuntos
Clara de Ovo/química , Armazenamento de Alimentos/métodos , Peptídeos/química , Animais , Galinhas , Conalbumina/química , Conalbumina/metabolismo , Espectrometria de Massas , Ovomucina/química , Ovomucina/metabolismo , Peptídeos/metabolismo , Espectrometria de Massas em Tandem , Temperatura
17.
Food Res Int ; 108: 465-474, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29735080

RESUMO

Protein susceptibility to in vitro gastrointestinal digestion of ovomucin-depleted egg white (OdEW) adjusted to pH 4, 5, 7 and 9 and processed by heat (60 and 80 °C for 10 min) or pulsed electric fields (PEF) (1.4-1.8 kV/cm, 259-695 kJ/kg) was studied by assessing peptide production, proteolytic pattern, and the final peptide profile. Ovotransferrin was more susceptible to pepsin hydrolysis than lysozyme, with ovalbumin showing the highest proteolytic resistance. Ovalbumin was, however, hydrolyzed by pancreatin to produce a stable fragment. Heat treatment of OdEW solutions at 60 °C had little impact on protein susceptibility with the ovalbumin dimers formed having a comparable resistance to pepsinolysis as ovalbumin. Heating at 80 °C significantly enhanced protein susceptibility, as ovalbumin and protein aggregates formed were completely hydrolyzed within 30 min of pepsinolysis. Adjusting OdEW solution to pH 4 and treating with PEF at 695 kJ/kg enhanced protein susceptibility, similar to heat treatment at 80 °C, mainly owing to the enhanced enzymatic hydrolysis of ovalbumin. PEF processing can, therefore, increase protein digestion while minimizing protein aggregation, which will enhance protein functionality in egg whites.


Assuntos
Digestão , Proteínas Dietéticas do Ovo/química , Eletricidade , Manipulação de Alimentos/métodos , Temperatura Alta , Ovomucina/isolamento & purificação , Peptídeo Hidrolases/química , Peptídeos/química , Cromatografia Líquida , Conalbumina/química , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Hidrólise , Muramidase/química , Ovalbumina/química , Agregados Proteicos , Proteólise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
J Exp Biol ; 221(Pt 10)2018 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-29666198

RESUMO

Predation risk is thought to modify the physiology of prey mainly through the stress response. However, little is known about its potential effects on the immunity of animals, particularly in young individuals, despite the importance of overcoming wounding and pathogen aggression following a predator attack. We investigated the effect of four progressive levels of nest predation risk on several components of the immune system in common blackbird (Turdus merula) nestlings by presenting them with four different calls during 1 h: non-predator calls, predator calls, parental alarm calls and conspecific distress calls to induce a null, moderate, high and extreme level of risk, respectively. Nest predation risk induced an increase in ovotransferrin, immunoglobulin and the number of lymphocytes and eosinophils. Thus, the perception of a potential predator per se could stimulate the mobilization of a nestling's immune function and enable the organism to rapidly respond to the immune stimuli imposed by a predator attack. Interestingly, only high and extreme levels of risk caused immunological changes, suggesting that different immunological parameters are modulated according to the perceived level of threat. We also found a mediator role of parasites (i.e. Leucocytozoon) and the current health status of the individual, as only nestlings not parasitized or in good body condition were able to modify their immune system. This study highlights a previously unknown link between predation risk and immunity, emphasizing the complex relationship among different selective pressures (predation, parasitism) in developing organisms and accentuating the importance of studying predation from a physiological point of view.


Assuntos
Comportamento Predatório , Aves Canoras/imunologia , Vocalização Animal , Animais , Animais Recém-Nascidos/imunologia , Animais Recém-Nascidos/parasitologia , Conalbumina/sangue , Eosinófilos , Haemosporida/isolamento & purificação , Imunoglobulinas/sangue , Contagem de Linfócitos , Comportamento de Nidação , Infecções por Protozoários/imunologia , Aves Canoras/crescimento & desenvolvimento , Aves Canoras/parasitologia , Espanha
19.
J Agric Food Chem ; 66(11): 2775-2782, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29502401

RESUMO

Ovotransferrin, the major protein in egg white, is a member of transferrin family. The objective of this study was to study the effects of ovotransferrin on cell proliferation, differentiation, mineralization and osteoclastogenesis of bone osteoblast cells. Effect of ovotransferrin (concentrations ranging from 1 to 1000 µg/mL) on the proliferation, differentiation, and mineralization of mouse osteoblast cells MC3T3-E1 was determined by 5-bromo-2-deoxyuridine (BrdU) incorporation assay, Western blot, immunofluorescence, and Alizarin-S red staining, respectively. Our results showed that ovotransferrin stimulated cell proliferation (enhanced BrdU incorporation), differentiation (enhanced expression of alkaline phosphatase and type-I collagen), and mineralization (increased calcium deposits) in a dose-dependent manner. Furthermore, ovotransferrin could increase the expression of osteoprotegerin (OPG) while decreasing the expression of receptor activator of nuclear factor kappa-B ligand (RANKL), suggesting its role in inhibition of bone resorption. This study demonstrated for the first time that ovotransferrin might promote bone formation while preventing bone resorption, which might open up a new application of egg white protein ovotransferrin as a functional ingredient in bone health management.


Assuntos
Conalbumina/metabolismo , Clara de Ovo/química , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese , Osteoporose/metabolismo , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Proliferação de Células , Galinhas , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Humanos , Camundongos , Osteoporose/genética , Osteoporose/fisiopatologia , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo
20.
Electrophoresis ; 39(8): 1054-1061, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29405312

RESUMO

To separate and extract the native states of lysozyme from chicken egg white, a hybrid method for the mobilization of proteins after non-denaturing gel isoelectric focusing (IEF) combined with detection of lysozyme activity was developed. When the proteins in the chicken egg white were first separated using non-denaturing gel IEF, a lysozyme was obtained at the top of the gel column at the cathode end of the IEF. And, when the IEF-separated proteins of the egg white were mobilized by replacing the cathodic sodium hydroxide solution with phosphoric acid solution, an additional active state of the lysozyme that could be bound to proteins, such as ovotransferrin, was extracted from the solution. Furthermore, it was shown that the addition of lysozyme, obtained via IEF, to pure ovotransferrin generated a complex manifesting lysozyme activity, clearly indicating a successful reconstruction of the lysozyme-ovotransferrin complex in vitro. Therefore, the obtained results demonstrated that the native states of lysozymes, such as lysozyme and the lysozyme-ovotransferrin complex, can be effectively separated and extracted using non-denaturing gel IEF. Thus, this method can be applied to separate and extract different charge states of native proteins that retain their biological activities.


Assuntos
Clara de Ovo/química , Focalização Isoelétrica/métodos , Muramidase/isolamento & purificação , Animais , Galinhas , Conalbumina/química , Focalização Isoelétrica/normas , Complexos Multiproteicos/isolamento & purificação , Muramidase/metabolismo
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