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1.
Talanta ; 233: 122579, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215071

RESUMO

An electrospray is a dispersed nebula of charged droplets produced under the influence of a strong electric field. The charged droplets subsequently result in ions in the gas phase. Therefore, electrospray is a commonly used method for transferring liquids to the gas phase while ionizing its constituents at the same time. In this work, we investigate the performance of an electrospray ionization ion mobility spectrometer by varying the electric field strength in the desolvation region. In particular, we investigate a new tristate ion shutter with increased sensitivity for ions with higher molecular mass and lower ion mobility that are usually suppressed by classical Bradbury-Nielsen or Tyndall-Powell ion shutters when using short gating times as required for high resolving power. The electric field in the tristate ion shutter affects the optimal ratio of the electric field strengths in the drift and desolvation region. Furthermore, the solvent flow rate needs to be considered when setting the field strengths in the desolvation region. However, a higher electric field strength in the desolvation region affects the field at the emitter tip. For this reason, a smaller ratio of the drift field strength and the desolvation field strength is beneficial, especially since higher solvent flow rates require higher fields to initiate an electrospray. In this work, we use tetraoctylammonium bromide as an instrument standard and the fungicide metalaxyl, the herbicide isoproturon and the antibiotic cefuroxime as model compounds.


Assuntos
Espectrometria de Massas por Ionização por Electrospray , Íons , Peso Molecular
2.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198692

RESUMO

The formation of fibrillar aggregates of the amyloid beta peptide (Aß) in the brain is one of the hallmarks of Alzheimer's disease (AD). A clear understanding of the different aggregation steps leading to fibrils formation is a keystone in therapeutics discovery. In a recent study, we showed that Aß40 and Aß42 form dynamic micellar aggregates above certain critical concentrations, which mediate a fast formation of more stable oligomers, which in the case of Aß40 are able to evolve towards amyloid fibrils. Here, using different biophysical techniques we investigated the role of different fractions of the Aß aggregation mixture in the nucleation and fibrillation steps. We show that both processes occur through bimolecular interplay between low molecular weight species (monomer and/or dimer) and larger oligomers. Moreover, we report here a novel self-catalytic mechanism of fibrillation of Aß40, in which early oligomers generate and deliver low molecular weight amyloid nuclei, which then catalyze the rapid conversion of the oligomers to mature amyloid fibrils. This fibrillation catalytic activity is not present in freshly disaggregated low-molecular weight Aß40 and is, therefore, a property acquired during the aggregation process. In contrast to Aß40, we did not observe the same self-catalytic fibrillation in Aß42 spheroidal oligomers, which could neither be induced to fibrillate by the Aß40 nuclei. Our results reveal clearly that amyloid fibrillation is a multi-component process, in which dynamic collisions between different interacting species favor the kinetics of amyloid nucleation and growth.


Assuntos
Peptídeos beta-Amiloides/química , Benzotiazóis/química , Fenômenos Biofísicos , Catálise , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Cinética , Peso Molecular , Conformação Proteica
3.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205146

RESUMO

The objective of the present study was to investigate the proximate composition, antiradical properties and hepatoprotective activity of three species of shellfish, Corbicula japonica, Spisula sachalinensis, and Anadara broughtonii, from the coastal areas of Far East Russia. Biologically active peptides such as taurine (3.74 g/100 g protein) and ornithine (2.12 g/100 g protein) have been found in the tissues of A. broughtonii. C. japonica contains a high amount of ornithine (5.57 g/100 g protein) and taurine (0.85 g/100 g protein). The maximum DPPH and ABTS radical scavenging activity (36.0 µg ascorbic acid/g protein and 0.68 µmol/Trolox equiv/g protein, respectively) was determined for the tissue of C. japonica. The protein and peptide molecular weight distribution of the shellfish tissue water extracts was investigated using HPLC. It was found that the amount of low molecular weight proteins and peptides were significantly and positively correlated with radical scavenging activity (Pearson's correlation coefficient = 0.96), while the amount of high molecular weight proteins negatively correlated with radical scavenging activity (Pearson's correlation coefficient = -0.86). Hepatoprotective activity, measured by the survival rate of HepG2 hepatocytes after cotreatment with t-BHP, was detected for C. japonica. The highest protection (95.3 ± 2.4%) was achieved by the cold water extract of C. japonica at the concentration of 200 mg/mL. Moreover, oral administration of hot water extract of C. japonica to rats before the treatment with CCl4 exhibited a markedly protective effect by lowering serum levels of ALT and AST, inhibiting the changes in biochemical parameters of functional state of rat liver, including MDA, SOD, GSH and GST.


Assuntos
Antioxidantes/farmacologia , Arcidae/química , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Corbicula/química , Hepatócitos/citologia , Frutos do Mar/análise , Spisula/química , terc-Butil Hidroperóxido/efeitos adversos , Administração Oral , Animais , Antioxidantes/química , Tetracloreto de Carbono/efeitos adversos , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Modelos Animais de Doenças , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Masculino , Peso Molecular , Ornitina/isolamento & purificação , Ratos , Federação Russa , Frutos do Mar/classificação , Taurina/isolamento & purificação
4.
Bratisl Lek Listy ; 122(8): 582-589, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34282625

RESUMO

OBJECTIVES: Low molecular weight heparin (LMWH) may provide beneficial effects on outcomes of COVID-19. We aimed to examine the impact of LMWH treatment on clinical outcomes (duration of hospitalization, admission to intensive care unit, the requirement for mechanical ventilation, and death) of COVID-19 patients with normal D-dimer levels at admission. BACKGROUND: Coronavirus disease-2019 (COVID-19) predisposes patients to arterial and venous thrombosis. METHODS: In this retrospective, multicentre and observational study we analysed the data of 308 confirmed COVID-19 patients with normal D-dimer levels at initial admission. After propensity score matching (PSM) patients were grouped; Group 1; patients who received LMWH with D-dimer ≤0.5 mg/L, Group 2; patients who received LMWH after D-dimer levels exceeded 0.5 mg/L, and Group 3; patients who did not receive LMWH. RESULTS: After PSM, each group comprised 40 patients. The patients in Group1 had the best clinical outcomes compared to the other groups. Group 3 had the worst clinical outcomes (p<0.005). The benefit of LMWH increased with early prophylactic therapy especially when started while the D-dimer levels were ≤0.5 mg/L. CONCLUSION: Our results strongly suggest that proactive LMWH therapy improves clinical outcomes in hospitalized COVID-19 patients even with normal D-dimer levels (≤ 0.5 mg/L) (Tab. 3, Fig. 2, Ref. 34).


Assuntos
COVID-19 , Heparina de Baixo Peso Molecular , Anticoagulantes , Heparina , Humanos , Peso Molecular , Estudos Retrospectivos , SARS-CoV-2
5.
Int J Mol Sci ; 22(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34299058

RESUMO

This study concerns green thermoplastic polyurethanes (TPU) obtained by controlling the chemical structure of flexible segments. Two types of bio-based polyether polyols-poly(trimethylene glycol)s-with average molecular weights ca. 1000 and 2700 Da were used (PO3G1000 and PO3G2700, respectively). TPUs were prepared via a two-step method. Hard segments consisted of 4,4'-diphenylmethane diisocyanates and the bio-based 1,4-butanodiol (used as a chain extender and used to control the [NCO]/[OH] molar ratio). The impacts of the structure of flexible segments, the amount of each type of prepolymer, and the [NCO]/[OH] molar ratio on the chemical structure and selected properties of the TPUs were verified. By regulating the number of flexible segments of a given type, different selected properties of TPU materials were obtained. Thermal analysis confirmed the high thermal stability of the prepared materials and revealed that TPUs based on a higher amount of prepolymer synthesized from PO3G2700 have a tendency for cold crystallization. An increase in the amount of PO3G1000 at the flexible segments caused an increase in the tensile strength and decrease in the elongation at break. Melt flow index results demonstrated that the increase in the amount of prepolymer based on PO3G1000 resulted in TPUs favorable in terms of machining.


Assuntos
Materiais Biocompatíveis/química , Poliuretanos/química , Resistência à Tração , Peso Molecular , Temperatura
6.
Langmuir ; 37(28): 8474-8485, 2021 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-34236863

RESUMO

Protein stability and performance in various natural and artificial systems incorporating many other macromolecules for therapeutic, diagnostic, sensor, and biotechnological applications attract increasing interest with the expansion of these technologies. Here we address the catalytic activity of lysozyme protein (LYZ) in the presence of a polyethylene glycol (PEG) crowder in a broad range of concentrations and temperatures in aqueous solutions of two different molecular mass PEG samples (Mw = 3350 and 10000 g/mol). The phase behavior of PEG-protein solutions is examined by using dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS), while the enzyme denaturing is monitored by using an activity assay (AS) and circular dichroism (CD) spectroscopy. Molecular dynamic (MD) simulations are used to illustrate the effect of PEG concentration on protein stability at high temperatures. The results demonstrate that LYZ residual activity after 1 h incubation at 80 °C is improved from 15% up to 55% with the addition of PEG. The improvement is attributed to two underlying mechanisms. (i) Primarily, the stabilizing effect is due to the suppression of the enzyme aggregation because of the stronger PEG-protein interactions caused by the increased hydrophobicity of PEG and lysozyme at elevated temperatures. (ii) The MD simulations showed that the addition of PEG to some degree stabilizes the secondary structures of the enzyme by delaying unfolding at elevated temperatures. The more pronounced effect is observed with an increase in PEG concentration. This trend is consistent with CD and AS experimental results, where the thermal stability is strengthened with increasing of PEG concentration and molecular mass. The results show that the highest stabilizing effect is approached at the critical overlap concentration of PEG.


Assuntos
Polietilenoglicóis , Estabilidade Enzimática , Peso Molecular , Estabilidade Proteica , Espalhamento a Baixo Ângulo , Difração de Raios X
7.
Molecules ; 26(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205933

RESUMO

Biothiols are extremely powerful antioxidants that protect cells against the effects of oxidative stress. They are also considered relevant disease biomarkers, specifically risk factors for cardiovascular disease. In this paper, a new procedure for the simultaneous determination of human serum albumin and low-molecular-weight thiols in plasma is described. The method is based on the pre-column derivatization of analytes with a thiol-specific fluorescence labeling reagent, monobromobimane, followed by separation and quantification through reversed-phase high-performance liquid chromatography with fluorescence detection (excitation, 378 nm; emission, 492 nm). Prior to the derivatization step, the oxidized thiols are converted to their reduced forms by reductive cleavage with sodium borohydride. Linearity in the detector response for total thiols was observed in the following ranges: 1.76-30.0 mg mL-1 for human serum albumin, 0.29-5.0 nmol mL-1 for α-lipoic acid, 1.16-35 nmol mL-1 for glutathione, 9.83-450.0 nmol mL-1 for cysteine, 0.55-40.0 nmol mL-1 for homocysteine, 0.34-50.0 nmol mL-1 for N-acetyl-L-cysteine, and 1.45-45.0 nmol mL-1 for cysteinylglycine. Recovery values of 85.16-119.48% were recorded for all the analytes. The developed method is sensitive, repeatable, and linear within the expected ranges of total thiols. The devised procedure can be applied to plasma samples to monitor biochemical processes in various pathophysiological states.


Assuntos
Compostos Bicíclicos com Pontes/química , Albumina Sérica Humana/análise , Compostos de Sulfidrila/análise , Cromatografia de Fase Reversa , Humanos , Peso Molecular , Oxirredução , Albumina Sérica Humana/química , Compostos de Sulfidrila/química
8.
Molecules ; 26(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34206027

RESUMO

The utilization of biorefinery lignins as a renewable resource for the production of bio-based chemicals and materials remain a challenge because of the high polysaccharide content of this variety of lignins. This study provides two simple methods; (i) the alkaline hydrolysis-acid precipitation method and (ii) the acid hydrolysis method for the removal of polysaccharides from polymeric biorefinery lignin samples. Both purification strategies are optimized for two different hardwood hydrolysis lignins, HL1 and HL2, containing 15.1% and 10.1% of polysaccharides, respectively. The treated lignins are characterized by polysaccharide content, molecular weight, hydroxyl content, and Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR). Preliminary techno-economic calculations are also carried out for both purification processes to assess the economic potential of these technologies. The results indicate that both protocols could be used for the purification of HL1 and HL2 hydrolysis lignins because of the minimal polysaccharide content obtained in the treated lignins. Nevertheless, from an industrial and economic perspective the acid hydrolysis technology using low acid concentrations and high temperatures is favored over the alkaline hydrolysis-acid precipitation strategy.


Assuntos
Lignina/química , Polissacarídeos/análise , Madeira/química , Biotecnologia , Precipitação Química , Hidrólise , Peso Molecular , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Int J Mol Sci ; 22(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34281277

RESUMO

The aim of this research was to analyze the heterologous expression, purification, and immunoregulatory activity of recombinant YGP40 (rYGP40), the potential precursor of the yolkin peptide complex. The ygp40 coding sequence was codon optimized, successfully expressed in the E. coli system, and purified from inclusion bodies with a yield of about 1.1 mg/L of culture. This study showed that the protein exhibits immunomodulatory activity, expressed by the stimulation of TNF-α and IL-10 production and nitric oxide induction at a level comparable to that of the natural yolkin peptide complex obtained by other authors from hen egg yolk. At the highest dose of 100 µg/mL, rYGP40 also caused the up-regulation of iNOS expression in murine bone marrow-derived macrophages (BMDM). Moreover, no cytotoxic effects of rYGP40 on the BMDM cell line were observed.


Assuntos
Vitelogeninas/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Galinhas , Clonagem Molecular , Gema de Ovo/química , Feminino , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/genética , Fatores Imunológicos/farmacologia , Técnicas In Vitro , Interleucina-10/biossíntese , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Peso Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/farmacologia , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/biossíntese , Vitelogeninas/genética , Vitelogeninas/farmacologia
10.
Int J Nanomedicine ; 16: 4197-4208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34188469

RESUMO

Introduction: Intracellular protein delivery is emerging as a potential strategy to revolutionize therapeutics in the field of biomedicine, aiming at treating a wide range of diseases including cancer, inflammatory diseases and other oxidative stress-related disorders with high specificity. However, the current challenges and limitations are addressed to either synthetically or biologically through multipotency of engineering, such as protein modification, insufficient delivery of large-size proteins, deficiency or mutation of proteins, and high cytotoxicity. Methods: We prepared the nanocomposites by mixing protein with PEI1200 at a certain molar ratio and demonstrated that it can deliver proteins into living cells in high efficiency and safety through the following experiments, such as dynamic light scattering, fluorescent detection, agarose gel electrophoresis, ß-Galactosidase activity detection, immunofluorescence staining, digital fluorescent detection, cell viability assay and flow cytometry. Results: The self-assembly of PEI1200/protein nanocomposites with appropriate molar ratio (4:1 and 8:1) could provide efficiently delivery of active proteins to a variety of cell types in the presence of serum. The nanocomposites could continuously release protein up to 96 h in their desired intracellular locations. In addition, these nanocomposites were able to preserve protein activity while maintain low cytotoxicity (when final concentration <1 µg/mL). Conclusion: Collectively, PEI1200-based delivery system provided an alternative strategy to direct protein delivery in high efficiency and safety, offering increased potential applications in clinical biomedicine.


Assuntos
Espaço Intracelular/metabolismo , Polietilenoimina/química , Proteínas/administração & dosagem , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Proteínas de Fluorescência Verde/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Peso Molecular , Nanocompostos/química , Nanocompostos/ultraestrutura
12.
Molecules ; 26(9)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066584

RESUMO

The sensitive and selective detection of dopamine (DA) is very important for the early diagnosis of DA-related diseases. In this study, we reported the colorimetric detection of DA using Ganoderma lucidum polysaccharide (GLP) stabilized platinum nanoclusters (Ptn-GLP NCs). When Pt600-GLP NCs was added, 3,3',5,5'-tetramethylbenzidine (TMB) was rapidly catalyzed and oxidized to blue oxTMB, indicating the peroxidase-like activity of Pt600-GLP NCs. The catalytic reaction on the substrate TMB followed the Michaelis-Menton kinetics with the ping-pong mechanism. The mechanism of the colorimetric reaction was mainly due to the formation of hydroxyl radical (•OH). Furthermore, the catalytic reaction of Pt600-GLP NCs was used in the colorimetric detection of DA. The linear range for DA was 1-100 µM and the detection limit was 0.66 µM. The sensitive detection of DA using Pt-GLP NCs with peroxidase-like activity offers a simple and practical method that may have great potential applications in the biotechnology field.


Assuntos
Benzidinas/química , Dopamina/análise , Dopamina/sangue , Peroxidase/química , Polissacarídeos/química , Reishi/química , Encefalopatias/metabolismo , Catálise , Colorimetria , Humanos , Cinética , Limite de Detecção , Peso Molecular , Nanopartículas/química , Oxirredutases/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
13.
Molecules ; 26(9)2021 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-34066679

RESUMO

Microalgae are known to be rich in protein. In this study, we aim to investigate methods of producing and purifying proteins of 98 microalgae including Chlorella vulgaris, Arthrospira platensis, Nostoc sp., Dunaliella salina, and Pleurochrysis carterae (Baltic Sea). Therefore, we studied their amino acid composition and developed a two-stage protein concentrate purification method from the microalgae biomass. After an additional stage of purification, the mass fraction of protein substances with a molecular weight greater than 50 kDa in the protein concentrate isolated from the biomass of the microalga Dunaliella salina increased by 2.58 times as compared with the mass fraction before filtration. In the protein concentrate isolated from the biomass of the microalga Pleurochrysis cartera, the relative content of the fraction with a molecular weight greater than 50.0 kDa reached 82.4%, which was 2.43 times higher than the relative content of the same fractions in the protein concentrate isolated from this culture before the two-stage purification. The possibilities of large-scale industrial production of microalgae biomass and an expanded range of uses determine the need to search for highly productive protein strains of microalgae and to optimize the conditions for isolating amino acids from them.


Assuntos
Proteínas de Algas/química , Aminoácidos/química , Aminoácidos/isolamento & purificação , Chlorella vulgaris/química , Haptófitas/química , Microalgas/química , Nostoc/química , Spirulina/química , Biomassa , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Peso Molecular , Ultrafiltração
14.
Int J Mol Sci ; 22(10)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069497

RESUMO

The epidemiological success of Staphylococcus aureus as a versatile pathogen in mammals is largely attributed to its virulence factor repertoire and the sophisticated regulatory network controlling this virulon. Here we demonstrate that the low-molecular-weight protein arginine phosphatase PtpB contributes to this regulatory network by affecting the growth phase-dependent transcription of the virulence factor encoding genes/operons aur, nuc, and psmα, and that of the small regulatory RNA RNAIII. Inactivation of ptpB in S. aureus SA564 also significantly decreased the capacity of the mutant to degrade extracellular DNA, to hydrolyze proteins in the extracellular milieu, and to withstand Triton X-100 induced autolysis. SA564 ΔptpB mutant cells were additionally ingested faster by polymorphonuclear leukocytes in a whole blood phagocytosis assay, suggesting that PtpB contributes by several ways positively to the ability of S. aureus to evade host innate immunity.


Assuntos
Neutrófilos/metabolismo , Neutrófilos/microbiologia , Infecções Estafilocócicas/imunologia , Arginina/análogos & derivados , Arginina/química , Arginina/metabolismo , Proteínas de Bactérias/metabolismo , Parede Celular/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Humanos , Peso Molecular , Compostos Organofosforados/química , Compostos Organofosforados/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , RNA Bacteriano/metabolismo , Staphylococcus aureus/metabolismo , Staphylococcus aureus/patogenicidade , Fatores de Virulência/metabolismo
15.
Anal Chem ; 93(26): 9267-9276, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34165952

RESUMO

Recent progress in the development and production of new, innovative protein therapeutics require rapid and adjustable high-resolution bioseparation techniques. Sodium dodecyl sulfate capillary gel electrophoresis (SDS-CGE) using a borate (B) cross-linked dextran (D) separation matrix is widely employed today for rapid consistency analysis of therapeutic proteins in manufacturing and release testing. Transient borate cross-linking of the semirigid dextran polymer chains leads to a high-resolution separation gel for SDS-protein complexes. To understand the migration and separation basis of the D/B gel, the present work explores various gel formulations of dextran monomer (2, 5, 7.5, and 10%) and borate cross-linker (2 and 4%) concentrations. Ferguson plots were analyzed for a mixture of protein standards with molecular weights ranging from 20 to 225 kDa, and the resulting nonlinear concave curves pointed to nonclassical sieving behavior. While the 2% D/4% B gel resulted in the fastest analysis time, the 10% D/2% B gel was found to produce the greatest separation window, even higher than with the 10% D/4% B gel, due to a significant increase in the electroosmotic flow of the former composition in the direction opposite to SDS-protein complex migration. The study then focused on SDS-CGE separation of a therapeutic monoclonal antibody and its subunits. A combination of molecular weight and shape selectivity as well as, to a lesser extent, surface charge density differences (due to glycosylation on the heavy chain) influenced migration. Greater molecular weight selectivity occurred for the higher monomer concentration gels, while improved glycoselectivity was obtained using a more dilute gel, even as low as 2% D/2% B. This latter gel took advantage of the dextran-borate-glycoprotein complexation. The study revealed that by modulating the dextran (monomer) and borate (cross-linker) concentration ratios of the sieving matrix, one can optimize the separation for specific biopharmaceutical modalities with excellent column-to-column, run-to-run, and gel-to-gel migration time reproducibilities (<0.96% relative standard deviation (RSD)). The widely used 10% dextran/4% borate gel represents a good screening option, which can then be followed by a modified composition, optimized for a specific separation as necessary.


Assuntos
Boratos , Dextranos , Eletroforese Capilar , Eletroforese em Gel de Poliacrilamida , Géis , Peso Molecular , Dodecilsulfato de Sódio
16.
Molecules ; 26(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072134

RESUMO

The interest in utilizing food-derived compounds therapeutically has been rising. With the growing prevalence of systematic chronic inflammation (SCI), efforts to find treatments that do not result in the side effects of current anti-inflammatory drugs are underway. Bioactive peptides (BAPs) are a particularly promising class of compounds for the treatment of SCI, and the abundance of high-quality seafood processing byproducts (SPB) makes it a favorable material to derive anti-inflammatory BAPs. Recent research into the structural properties of anti-inflammatory BAPs has found a few key tendencies including they tend to be short and of low molecular weight (LMW), have an overall positive charge, contain hydrophobic amino acids (AAs), and be rich in radical scavenging AAs. SPB-derived anti-inflammatory BAPs have been observed to work via inhibition of the NF-κB and MAPK pathways by disrupting the phosphorylation of IκBα and one or more kinases (ERK, JNK, and p38), respectively. Radical scavenging capacity has also been shown to play a significant role in the efficacy of SPB-derived anti-inflammatory BAPs. To determine if SPB-derived BAPs can serve as an effective treatment for SCI it will be important to understand their properties and mechanisms of action, and this review highlights such findings in recent research.


Assuntos
Anti-Inflamatórios/farmacologia , Peptídeos/química , Aminoácidos/química , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Antioxidantes/farmacologia , Dano ao DNA , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Peixes , Interações Hidrofóbicas e Hidrofílicas , Inflamação , MAP Quinase Quinase 4/metabolismo , Macrófagos/metabolismo , Peso Molecular , Inibidor de NF-kappaB alfa/metabolismo , Estresse Oxidativo , Reprodutibilidade dos Testes , Frutos do Mar , Proteínas de Frutos do Mar , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
18.
Food Chem ; 362: 130190, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34082288

RESUMO

To explore the potential application of proteases from soybean seedlings in the debittering of soybean protein hydrolysates, soybean seeds were germinated from 1 to 10 days. It was found that the sixth day seedlings exhibited highest proteases activity (130 U/g). After partial purification, the activity of proteases (PSP) from the sixth day seedlings further increased to 2675 U/g. In addition, PSP exhibited maximum activity at 50 â„ƒ and pH 5.5, and mainly comprised of two proteins with the molecular weight of 64.57 and 25.12 kDa respectively. PSP could decrease the bitterness score of the soybean protein isolate hydrolysate (SPIH) produced by Alcalase 2.4L from 3.45 to 0 in 3 h. Meanwhile, the degree of hydrolysis of SPIH slightly increased from 11.87% to 15.61% without reducing the antioxidant activity. This study may provide a solution to the contradiction between removing the bitterness of soybean protein hydrolysates and maintaining the bioactivity.


Assuntos
Peptídeo Hidrolases/metabolismo , Hidrolisados de Proteína/química , Plântula/enzimologia , Soja/enzimologia , Paladar , Antioxidantes/química , Antioxidantes/farmacologia , Germinação , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Peso Molecular , Peptídeo Hidrolases/química , Hidrolisados de Proteína/farmacologia , Sementes/metabolismo , Proteínas de Soja/química , Proteínas de Soja/metabolismo , Soja/química , Subtilisinas/química , Subtilisinas/metabolismo , Temperatura
19.
Food Chem ; 362: 130218, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34087713

RESUMO

In this research, three various Mw of chitosan (CS)-gallic acid (GA) conjugates were synthesized, characterized, and used for improvement of physicochemical stability of ß-carotene (BC) nanoemulsion (NE) by layer-by-layer technique. GA conjugation degrees were in the following order: HCS (125.6 mg/g) > MCS (102.3 mg/g) > LCS (74.6 mg/g) at GA:CS mass ratio of 0.5:1. Three varying Mw of CS-GA conjugates exhibited pronouncedly higher antioxidant abilities than native CS. For native CS, antioxidant abilities increased with the decrease of Mw. However, HCS-GA conjugate showed the highest antioxidant activity, due to the higher GA conjugation degrees and decreased intramolecular hydrogen bonds and crystallinity in HCS-GA conjugate. CS-GA conjugates substantially improved BC chemical stability in NE than CS and BC retentions were in the following order: HCS-GA (76.8%) > MCS-GA (68.3%) > LCS-GA (53.4%) after 30 days storage. The results obtained may provide some useful information for the applications of CS-GA conjugates for nutraceuticals stabilization in food systems.


Assuntos
Quitosana/química , Emulsões/química , Ácido Gálico/química , beta Caroteno/química , Antioxidantes/química , Suplementos Nutricionais , Armazenamento de Alimentos , Peso Molecular , Nanoestruturas/química , Eletricidade Estática
20.
Molecules ; 26(9)2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-34064423

RESUMO

In the present study, we evaluated for the first time the photoprotective effect of fish bone bioactive peptides (FBBP) preparation isolated from silver carp (Hypophthalmichthys molitrix) discarded tissue using in vitro experimental models of skin cells exposed to ultraviolet B (UVB) irradiation and stressing agents. FBBP preparation was obtained by papain treatment of minced bones and centrifugal ultrafiltration, and the molecular weight (MW) distribution was characterized by size exclusion and reversed-phase high performance liquid chromatography (RP-HPLC). In vitro assessment of the effect of FBBP pretreatment in UVB-irradiated L929 fibroblasts and HaCaT keratinocytes revealed their cytoprotective activity. Their capacity to efficiently reduce reactive oxygen species (ROS) production and lipid peroxidation varied in a dose-dependent manner, and it was greater in fibroblasts. A decrease of proinflammatory cytokines secretion, in particular of tumor necrosis factor alpha (TNF-α), was found after FBBP pretreatment of THP-1-derived inflamed macrophages. Melanin production and tyrosinase activity investigated in UVB-irradiated Mel-Juso cells were lowered in direct relation to FBBP concentrations. FBBP fractions with high radical scavenging activity were separated by ion exchange chromatography, and two collagenic sequences were identified. All these results offer new scientific data on aquaculture fish bone-derived peptides confirming their ability to control the antioxidant, anti-inflammatory and pigmentation processes developed during UV irradiation of skin cells and recommend their use as valuable natural ingredients of photoprotective cosmeceutical products.


Assuntos
Osso e Ossos/efeitos dos fármacos , Inflamação/patologia , Peptídeos/farmacologia , Pigmentação , Pele/efeitos da radiação , Raios Ultravioleta , Animais , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Citoproteção/efeitos dos fármacos , Citoproteção/efeitos da radiação , Peixes , Células HaCaT/efeitos dos fármacos , Células HaCaT/efeitos da radiação , Humanos , Mediadores da Inflamação/metabolismo , Espaço Intracelular/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Malondialdeído/metabolismo , Melaninas/biossíntese , Camundongos , Peso Molecular , Oxirredução/efeitos dos fármacos , Oxirredução/efeitos da radiação , Peptídeos/isolamento & purificação , Pigmentação/efeitos dos fármacos , Pigmentação/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Espectrofotometria Ultravioleta , Células THP-1
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