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1.
J Mass Spectrom ; 59(7): e5058, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38842112

RESUMO

Analysis of noncovalent interactions between natural products and proteins is important for rapid screening of active ingredients and understanding their pharmacological activities. In this work, the intensity fading MALDI-TOF mass spectrometry (IF-MALDI-MS) method with improved reproducibility was implemented to investigate the binding interactions between saponins from Panax notoginseng and lysozyme. The benchmark IF-MALDI-MS experiment was established using N,N',N″-triacetylchitotriose-lysozyme as a model system. The reproducibility of ion intensities in IF-MALDI-MS was improved by scanning the whole sample deposition with a focused laser beam. The relative standard deviation (RSD) of deposition scanning IF-MALDI-MS is 5.7%. Similar decay trends of the relative intensities of notoginseng saponins against increasing amounts of lysozyme were observed for all six notoginseng saponins. The half-maximal fading concentration (FC50) was calculated to quantitatively characterize the binding affinity of each ligand based on the decay curve. According to the FC50 values obtained, the binding affinities of the six notoginseng saponins were evaluated in the following order: notoginsenoside S > notoginsenoside Fc > ginsenoside Rb1 > ginsenoside Rd > notoginsenoside Ft1 > ginsenoside Rg1. The binding order was in accordance with molecular docking studies, which showed hydrogen bonding might play a key role in stabilizing the binding interaction. Our results demonstrated that deposition scanning IF-MALDI-MS can provide valuable information on the noncovalent interactions between ligands and proteins.


Assuntos
Muramidase , Panax notoginseng , Saponinas , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Muramidase/química , Muramidase/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Saponinas/química , Saponinas/análise , Saponinas/metabolismo , Panax notoginseng/química , Ligação Proteica , Simulação de Acoplamento Molecular , Reprodutibilidade dos Testes , Animais , Trissacarídeos
2.
J Colloid Interface Sci ; 670: 357-363, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38763031

RESUMO

Carbon dots (CDs) are carbon nano materials (CNMs) that find use across several biological applications because of their water solubility, biocompatible nature, eco-friendliness, and ease of synthesis. Additionally, their physiochemical properties can be chemically tuned for further optimization towards specific applications. Here, we investigate the efficacy of C70-derived Graphene Acid Quantum Dots (GAQDs) in mitigating the transformation of soluble, monomeric Hen Egg-White Lysozyme (HEWL) to mature fibrils during its amyloidogenic trajectory. Our findings reveal that GAQDs exhibit dose-dependent inhibition of HEWL fibril formation (up to 70 % at 5 mg/mL) without affecting mitochondrial membrane potential or inducing apoptosis at the same density. Furthermore, GAQDs scavenged reactive oxygen species (ROS); achieving a 50 % reduction in ROS levels at a mere 100 µg/mL when exposed to a standard free radical generator. GAQDs were not only found to be biocompatible with a human neuroblastoma-derived SHSY-5Y cell line but also rescued the cells from rotenone-induced apoptosis. The GAQD-tolerance of SHSY-5Y cells coupled with their ability to restitute cells from rotenone-dependent apoptosis, when taken in conjunction with the biocompatibility data, indicate that GAQDs possess neuroprotective potential. The data position this class of CNMs as promising candidates for resolving aberrant cellular outputs that associate with the advent and progress of multifactorial neurodegenerative disorders including Parkinson's (PD) and Alzheimer's diseases (AD) wherein environmental causes are implicated (95 % etiology). The data suggest that GAQDs are a multifunctional carbon-based sustainable nano-platform at the intersection of nanotechnology and neuroprotection for advancing green chemistry-derived, sustainable healthcare solutions.


Assuntos
Apoptose , Grafite , Muramidase , Pontos Quânticos , Espécies Reativas de Oxigênio , Pontos Quânticos/química , Humanos , Grafite/química , Grafite/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Muramidase/química , Muramidase/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Animais , Tamanho da Partícula , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/química , Carbono/química , Propriedades de Superfície , Potencial da Membrana Mitocondrial/efeitos dos fármacos
3.
Neurosci Lett ; 833: 137825, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38768939

RESUMO

Alzheimer's disease (AD) is a prevalent form of dementia in the elderly. There is currently no effective treatment available for this disease. Diagnosis of AD typically relies on clinical manifestations and specific biomarkers. The present study investigated the impact of inducing Alzheimer's disease (AD) in mice through the injection of lysozyme amyloids formed in the presence or absence of Bis (Indolyl) phenylmethane (BIPM) on alterations in plasma lipid profiles and liver enzyme activities. 24 adult Wistar rats were divided into control, Scopolamine, Lysozyme, BIPM groups and the blood samples were obtained from the groups for biochemical analysis. The findings of the study revealed significant changes in the plasma lipid profiles and liver enzyme markers of the Lysozyme group compared to the control group. The Lysozyme group exhibited elevated triglycerides (n = 6, P < 0.02) and LDL levels (n = 6, P < 0.02), reduced HDL (n = 6, P < 0.05) and cholesterol levels (n = 6, P < 0.02), and altered serum glutamic oxaloacetic transaminase (SGOT) level (n = 6, P < 0.05) compared to controls. While the level of serum glutamic pyruvic transaminase (SGPT) did not change significantly compared to the control. BIPM groups showed no significant changes in lipid or enzyme levels compared to controls. Overall, our research has shown that BIPM has the ability to modify the structure of HEWL aggregates, thereby improving the detrimental effects associated with AD caused by these aggregates. Analyzing lipid profiles and liver enzyme markers presents a promising avenue for targeted therapeutic approaches. These alterations observed in the plasma may potentially serve as candidate biomarkers for diagnosing this disease.


Assuntos
Doença de Alzheimer , Modelos Animais de Doenças , Hipocampo , Lipídeos , Fígado , Muramidase , Ratos Wistar , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Muramidase/sangue , Muramidase/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Lipídeos/sangue , Camundongos , Masculino , Indóis/administração & dosagem , Indóis/farmacologia , Amiloide/metabolismo , Ratos
4.
ACS Appl Mater Interfaces ; 16(22): 28290-28306, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38787331

RESUMO

Protein adsorption on solid surfaces is a process relevant to biological, medical, industrial, and environmental applications. Despite this wide interest and advancement in measurement techniques, the complexity of protein adsorption has frustrated its accurate prediction. To address this challenge, here, data regarding protein adsorption reported in the last four decades was collected, checked for completeness and correctness, organized, and archived in an upgraded, freely accessible Biomolecular Adsorption Database, which is equivalent to a large-scale, ad hoc, crowd-sourced multifactorial experiment. The shape and physicochemical properties of the proteins present in the database were quantified on their molecular surfaces using an in-house program (ProMS) operating as an add-on to the PyMol software. Machine learning-based analysis indicated that protein adsorption on hydrophobic and hydrophilic surfaces is modulated by different sets of operational, structural, and molecular surface-based physicochemical parameters. Separately, the adsorption data regarding four "benchmark" proteins, i.e., lysozyme, albumin, IgG, and fibrinogen, was processed by piecewise linear regression with the protein monolayer acting as breakpoint, using the linearization of the Langmuir isotherm formalism, resulting in semiempirical relationships predicting protein adsorption. These relationships, derived separately for hydrophilic and hydrophobic surfaces, described well the protein concentration on the surface as a function of the protein concentration in solution, adsorbing surface contact angle, ionic strength, pH, and temperature of the carrying fluid, and the difference between pH and the isoelectric point of the protein. When applying the semiempirical relationships derived for benchmark proteins to two other "test" proteins with known PDB structure, i.e., ß-lactoglobulin and α-lactalbumin, the errors of this extrapolation were found to be in a linear relationship with the dissimilarity between the benchmark and the test proteins. The work presented here can be used for the estimation of operational parameters modulating protein adsorption for various applications such as diagnostic devices, pharmaceuticals, biomaterials, or the food industry.


Assuntos
Mineração de Dados , Interações Hidrofóbicas e Hidrofílicas , Propriedades de Superfície , Adsorção , Proteínas/química , Muramidase/química , Muramidase/metabolismo , Bases de Dados de Proteínas , Aprendizado de Máquina
5.
Mikrochim Acta ; 191(6): 307, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713296

RESUMO

An assay that integrates histidine-rich peptides (HisRPs) with high-affinity aptamers was developed enabling the specific and sensitive determination of the target lysozyme. The enzyme-like activity of HisRP is inhibited by its interaction with a target recognized by an aptamer. In the presence of the target, lysozyme molecules progressively assemble on the surface of HisRP in a concentration-dependent manner, resulting in the gradual suppression of enzyme-like activity. This inhibition of HisRP's enzyme-like activity can be visually observed through color changes in the reaction product or quantified using UV-visible absorption spectroscopy. Under optimal conditions, the proposed colorimetric assay for lysozyme had a detection limit as low as 1 nM and exhibited excellent selectivity against other nonspecific interferents. Furthermore, subsequent research validated the practical applicability of the developed colorimetric approach to saliva samples, indicating that the assay holds significant potential for the detection of lysozymes in samples derived from humans.


Assuntos
Colorimetria , Muramidase , Saliva , Muramidase/análise , Muramidase/química , Muramidase/metabolismo , Colorimetria/métodos , Humanos , Saliva/química , Saliva/enzimologia , Limite de Detecção , Peptídeos/química , Aptâmeros de Nucleotídeos/química , Proteínas/análise , Técnicas Biossensoriais/métodos , Histidina/análise , Histidina/química
6.
Int J Biol Macromol ; 270(Pt 2): 132332, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38768914

RESUMO

Two of the deadliest infectious diseases, COVID-19 and tuberculosis (TB), have combined to establish a worldwide pandemic, wreaking havoc on economies and claiming countless lives. The optimised, multitargeted medications may diminish resistance and counter them together. Based on computational expression studies, 183 genes were co-expressed in COVID-19 and TB blood samples. We used the multisampling screening algorithms on the top ten co-expressed genes (CD40, SHP2, Lysozyme, GATA3, cCBL, SIVmac239 Nef, CD69, S-adenosylhomocysteinase, Chemokine Receptor-7, and Membrane Protein). Imidurea is a multitargeted inhibitor for COVID-19 and TB, as confirmed by extensive screening and post-filtering utilising MM\GBSA algorithms. Imidurea has shown docking and MM\GBSA scores of -8.21 to -4.75 Kcal/mol and -64.16 to -29.38 Kcal/mol, respectively. The DFT, pharmacokinetics, and interaction patterns suggest that Imidurea may be a drug candidate, and all ten complexes were tested for stability and bond strength using 100 ns for all MD atoms. The modelling findings showed the complex's repurposing potential, with a cumulative deviation and fluctuation of <2 Å and significant intermolecular interaction, which validated the possibilities. Finally, an inhibition test was performed to confirm our in-silico findings on SARS-CoV-2 Delta variant infection, which was suppressed by adding imidurea to Vero E6 cells after infection.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Simulação de Acoplamento Molecular , Mycobacterium tuberculosis , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Humanos , COVID-19/virologia , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/efeitos dos fármacos , Simulação de Dinâmica Molecular , Muramidase/química , Muramidase/metabolismo , Antivirais/farmacologia , Antivirais/química , Ureia/farmacologia , Ureia/química , Antígenos de Diferenciação de Linfócitos T/metabolismo
7.
Phys Chem Chem Phys ; 26(20): 14766-14776, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38716816

RESUMO

Hybrid ionic fluids (HIFs) are newly emerging and fascinating sustainable solvent media, which are attracting a great deal of scientific interest in protecting the native structure of proteins. For a few decades, there has been a demand to consider ionic liquids (ILs) and deep eutectic solvents (DESs) as biocompatible solvent media for enzymes; however, in some cases, these solvent media also show limitations. Therefore, this work focuses on synthesising novel HIFs to intensify the properties of existing ILs and DESs by mixing them. Herein, HIFs have been synthesised by the amalgamation of a deep eutectic solvent (DES) and an ionic liquid (IL) with a common cation or anion. Later on, the stability and activity of hen's egg white lysozyme (Lyz) in the presence of biocompatible solvent media and HIFs were studied by various techniques such as UV-vis, steady-state fluorescence, circular dichroism (CD), Fourier transform infrared spectroscopy (FT-IR) and dynamic light scattering (DLS) measurements. This work emphasises the effect of a DES (synthesised using 1 : 2 choline chloride and malonic acid) [Maline], ILs (1-butyl-3-methylimidazolium chloride [BMIM]Cl or choline acetate [Chn][Ac]) and their corresponding HIFs on the structure and functionality of Lyz. Moreover, we also studied the secondary structure, thermal stability, enzymatic activity and thermodynamic profile of Lyz at pH = 7 in the presence of varying concentrations (0.1 to 0.5 M) of [BMIM]Cl and [Chn][Ac] ILs, Maline as a DES, and Maline [BMIM]Cl (HIF1) and Maline [Chn][Ac] (HIF2). Spectroscopic results elucidate that ILs affect the activity and structural stability of Lyz. In contrast, the stability and activity are inhibited by DES and are enhanced by HIFs at all the studied concentrations. Overall, the experimental results studied explicitly elucidate that the structure and stability of Lyz are maintained in the presence of HIF1 while these properties are intensified in HIF2. This study shows various applications in biocompatible green solvents, particularly in the stability and functionality of proteins, due to their unique combination where the properties counteract the negative effect of either DESs or ILs in HIFs.


Assuntos
Solventes Eutéticos Profundos , Estabilidade Enzimática , Líquidos Iônicos , Muramidase , Líquidos Iônicos/química , Muramidase/química , Muramidase/metabolismo , Solventes Eutéticos Profundos/química , Solventes/química , Animais , Galinhas , Colina/química
8.
Dalton Trans ; 53(20): 8535-8540, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38727007

RESUMO

The reactivity of the anticancer drug picoplatin (cis-amminedichlorido(2-methylpyridine)platinum(II) complex) with the model proteins hen egg white lysozyme (HEWL) and bovine pancreatic ribonuclease (RNase A) was investigated by electrospray ionisation mass spectrometry (ESI MS) and X-ray crystallography. The data were compared with those previously obtained for the adducts of these proteins with cisplatin, carboplatin and oxaliplatin under the same experimental conditions. ESI-MS data show binding of Pt to both proteins, with fragments retaining the 2-methylpyridine ligand and, possibly, a chloride ion. X-ray crystallography identifies different binding sites on the two proteins, highlighting a different behaviour of picoplatin in the absence or presence of dimethyl sulfoxide (DMSO). Metal-containing fragments bind to HEWL close to the side chains of His15, Asp18, Asp119 and both Lys1 and Glu7, whereas they bind to RNase A on the side chain of His12, Met29, His48, Asp53, Met79, His105 and His119. The data suggest that the presence of DMSO favours the loss of 2-methylpyridine and alters the ability of the Pt compound to bind to the two proteins. With both proteins, picoplatin appears to behave similarly to cisplatin and carboplatin when dissolved in DMSO, whereas it behaves more like oxaliplatin in the absence of the coordinating solvent. This study provides important insights into the pharmacological profile of picoplatin and supports the conclusion that coordinating solvents should not be used to evaluate the biological activities of Pt-based drugs.


Assuntos
Muramidase , Compostos Organoplatínicos , Ribonuclease Pancreático , Muramidase/química , Muramidase/metabolismo , Ribonuclease Pancreático/química , Ribonuclease Pancreático/metabolismo , Animais , Cristalografia por Raios X , Compostos Organoplatínicos/química , Compostos Organoplatínicos/metabolismo , Bovinos , Ligação Proteica , Sítios de Ligação , Modelos Moleculares , Galinhas , Espectrometria de Massas por Ionização por Electrospray , Dimetil Sulfóxido/química , Carboplatina/química , Carboplatina/metabolismo
9.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38745481

RESUMO

Lysozyme is often used as a feed additive to act as an antibacterial protein that boosts the immune system of livestock and poultry while protecting against pathogens. To investigate the effects of recombinant human lysozyme (rhLYZ) from Pichia pastoris and chlortetracycline on broiler chicken's production performance, antioxidant characteristics, and intestinal microbiota, a total of 200, 1-d-old male Arbor Acres broiler chickens (46.53 ±â€…0.42 g) were selected for a 42-d experiment. Dietary treatments included a basal diet of corn-soybean meal supplemented with either 0 mg/kg (CON), 50 mg/kg aureomycin (ANT), 20 mg/kg rhLYZ (LOW), 60 mg/kg rhLYZ (MEDIUM), or 180 mg/kg rhLYZ (HIGH). Compared with CON, MEDIUM diet increased (P < 0.05) average daily gain (67.40 g) of broilers from day 22 to 42. In the early (1.29) and overall phases (1.69), MEDIUM led to a reduction (P < 0.05) in the feed conversion ratio of broiler chickens. Furthermore, in comparison to the CON and ANT, MEDIUM exhibited reduced (P < 0.05) levels of INF-γ and tumor necrosis factor-α in the serum. In the cecum, the abundance of Monoglobus and Family_XIII_AD3011_group was lower (P < 0.05) in the MEDIUM treatment compared to CON. Overall, supplementation of 60 mg/kg of rhLYZ improved growth performance, nutrient utilization efficiency, and serum immune function, while also influencing the composition of intestinal microbiota. This suggests lysozyme's potential to replace antibiotic additives in feed.


The aim of this study was to explore the effects of recombinant human lysozyme (rhLYZ) produced from Pichia pastoris and chlortetracycline on broiler chicken performance, antioxidant properties, and gut microbiota. A 42-d experiment was conducted, involving 200 1-d-old male Arbor Acres broiler chickens. We provided different diets: a standard diet (CON), a diet with 50 mg/kg aureomycin (ANT), a diet with 20 mg/kg rhLYZ (LOW), a diet with 60 mg/kg rhLYZ (MEDIUM), or a diet with 180 mg/kg rhLYZ (HIGH). The results showed that, compared to the control group, the MEDIUM group significantly increased the average daily gain of broilers to 67.40 g from day 22 to 42. Additionally, the MEDIUM group exhibited a reduced feed conversion ratio during both the early and overall growth stages of the chickens. Furthermore, serum levels of INF-γ and tumor necrosis factor-α were lower in the MEDIUM group compared to both the CON and ANT groups. In the cecum, the abundance of Monoglobus and Family_XIII_AD3011_group was also lower in the MEDIUM treatment compared to the CON group. Overall, supplementation with 60 mg/kg of rhLYZ improved growth performance, nutrient utilization efficiency, and serum immune function in broiler chickens while also influencing the composition of their intestinal microbiota. This suggests the potential of lysozyme as a replacement for antibiotic additives in feed.


Assuntos
Ração Animal , Antioxidantes , Galinhas , Dieta , Suplementos Nutricionais , Muramidase , Proteínas Recombinantes , Animais , Galinhas/crescimento & desenvolvimento , Muramidase/metabolismo , Muramidase/farmacologia , Ração Animal/análise , Suplementos Nutricionais/análise , Masculino , Dieta/veterinária , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal , Humanos , Intestinos/efeitos dos fármacos
10.
ACS Appl Mater Interfaces ; 16(21): 27177-27186, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38753304

RESUMO

Biocompatible nanoparticles as drug carriers can improve the therapeutic efficiency of hydrophobic drugs. However, the synthesis of biocompatible and biodegradable polymeric nanoparticles can be time-consuming and often involves toxic solvents. Here, a simple method for protein-based stable drug-loaded particles with a narrow polydispersity is introduced. In this process, lysozyme is mixed with hydrophobic drugs (curcumin, ellipticine, and dasatinib) and fructose to prepare lysozyme-based drug particles of around 150 nm in size. Fructose is mixed with the drug to generate nanoparticles that serve as templates for the lysozyme coating. The effect of lysozyme on the physicochemical properties of these nanoparticles is studied by transmission electron microscopy (TEM) and scattering techniques (e.g., dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS)). We observed that lysozyme significantly stabilized the curcumin fructose particles for 7 days. Moreover, additional drugs, such as ellipticine and dasatinib, can be loaded to form dual-drug particles with narrow polydispersity and spherical morphology. The results also reveal that lysozyme dual ellipticine/dasatinib curcumin particles enhance the cytotoxicity and uptake on MCF-7 cells, RAW 264.7 cells, and U-87 MG cells due to the larger and rigid hydrophobic core. In summary, lysozyme in combination with fructose and curcumin can serve as a powerful combination to form protein-based stable particles for the delivery of hydrophobic drugs.


Assuntos
Curcumina , Dasatinibe , Portadores de Fármacos , Elipticinas , Muramidase , Nanopartículas , Muramidase/química , Muramidase/metabolismo , Nanopartículas/química , Curcumina/química , Curcumina/farmacologia , Animais , Humanos , Camundongos , Portadores de Fármacos/química , Dasatinibe/química , Dasatinibe/farmacologia , Elipticinas/química , Elipticinas/farmacologia , Células RAW 264.7 , Células MCF-7 , Tamanho da Partícula , Frutose/química , Interações Hidrofóbicas e Hidrofílicas , Sobrevivência Celular/efeitos dos fármacos , Linhagem Celular Tumoral
11.
Colloids Surf B Biointerfaces ; 239: 113936, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38703556

RESUMO

Hydrophilic antifouling polymers provide excellent antifouling effects under usual short-term use conditions, but the long-term accumulation of contaminants causes them to lose their antifouling properties. To overcome this drawback, surface-initiated ring-opening graft polymerization (SI-ROP) was performed on the surface of the material by applying the cyclic carbide monomer 4'-(fluorosulfonyl)benzyl-5-methyl-2-oxo-1,3-dioxane-5-carboxylate (FMC), which contains a sulfonylfluoride group on the side chain, followed by a "sulfur(IV)-fluorine exchange" (SuFEx) post click modification reaction to link the hydrophilic polyethylene glycol (PEG) to the polyFMC (PFMC) brush, and a novel antifouling strategy for self-polishing dynamic antifouling surfaces was developed. The experimental results showed that the antifouling surface could effectively prevent the adsorption of proteins such as bovine serum albumin (BSA, ∼96.4%), fibrinogen (Fg, ∼87.8%) and lysozyme (Lyz ∼69.4%) as well as the adhesion of microorganisms such as the bacteria Staphylococcus aureus (S. aureus) (∼87.5%) and HeLa cells (∼67.2%). Moreover, the enzymatically self-polished surface still has excellent antifouling properties. Therefore, this modification method has potential applications in the field of biosensors and novel antifouling materials.


Assuntos
Aderência Bacteriana , Incrustação Biológica , Cimento de Policarboxilato , Polietilenoglicóis , Soroalbumina Bovina , Staphylococcus aureus , Propriedades de Superfície , Staphylococcus aureus/efeitos dos fármacos , Cimento de Policarboxilato/química , Polietilenoglicóis/química , Incrustação Biológica/prevenção & controle , Aderência Bacteriana/efeitos dos fármacos , Humanos , Soroalbumina Bovina/química , Adsorção , Polimerização , Bovinos , Animais , Fibrinogênio/química , Fibrinogênio/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Muramidase/química , Muramidase/metabolismo , Muramidase/farmacologia
12.
Aquat Toxicol ; 272: 106959, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38768528

RESUMO

As one of the main components of marine pollution, microplastics (MPs) inevitably enter the mussel aquaculture environment. At the same time, pathogenic bacteria, especially pathogens such as Vibrio, can cause illness outbreaks, leading to large-scale death of mussels. The potential harm of MPs and pathogenic bacteria to bivalve remains unclear. This study designed two experiments (1) mussels (Mytilus galloprovincialis) were exposed to 100 particles/L or 1,000 particles/L polymethyl methacrylate (PMMA, 17.01 ± 6.74 µm) MPs and 1 × 107 CFU/mL Vibrio parahaemolyticus at the same time (14 days), and (2) mussels were exposed to 100 particles/L or 1,000 particles/L MPs for a long time (30 days) and then exposed to 1 × 107 CFU/mL V. parahaemolyticus to explore the effects of these two stresses on the mussel immune system. The results showed that after the combined exposure of V. parahaemolyticus and MPs, the lysosomal membrane stability of hemocytes decreased, lysozyme activity was inhibited, and hemocytes were induced to produce more lectins and defensins to fight pathogenic invasion. Long-term exposure to MPs caused a large amount of energy consumption in mussels, inhibited most of the functions of humoral immunity, increased the risk of mussel infection with pathogenic bacteria, and negatively affected mussel condition factor, the number of hemocytes, and the number of byssuses. Mussels may allocate more energy to deal with MPs and pathogenic bacterial infections rather than for growth. Above all, MPs exposure can affect mussel immune function or reduce its stress resistance, which in turn has an impact on mollusk farming.


Assuntos
Hemócitos , Microplásticos , Mytilus , Vibrio parahaemolyticus , Poluentes Químicos da Água , Animais , Mytilus/microbiologia , Mytilus/efeitos dos fármacos , Mytilus/imunologia , Microplásticos/toxicidade , Vibrio parahaemolyticus/fisiologia , Vibrio parahaemolyticus/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Hemócitos/efeitos dos fármacos , Hemócitos/imunologia , Muramidase/metabolismo , Sistema Imunitário/efeitos dos fármacos
13.
Nutrients ; 16(10)2024 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-38794693

RESUMO

Human milk (HM) contains the essential macronutrients and bioactive compounds necessary for the normal growth and development of newborns. The milk collected by human milk banks is stored frozen and pasteurized, reducing its nutritional and biological value. The purpose of this study was to determine the effect of hyperbaric storage at subzero temperatures (HS-ST) on the macronutrients and bioactive proteins in HM. As control samples, HM was stored at the same temperatures under 0.1 MPa. A Miris HM analyzer was used to determine the macronutrients and the energy value. The lactoferrin (LF), lysozyme (LYZ) and α-lactalbumin (α-LAC) content was checked using high-performance liquid chromatography, and an ELISA test was used to quantify secretory immunoglobulin A (sIgA). The results showed that the macronutrient content did not change significantly after 90 days of storage at 60 MPa/-5 °C, 78 MPa/-7 °C, 111 MPa/-10 °C or 130 MPa/-12 °C. Retention higher than 90% of LYZ, α-LAC, LF and sIgA was observed in the HM stored at conditions of up to 111 MPa/-10 °C. However, at 130 MPa/-12 °C, there was a reduction in LYZ and LF, by 39 and 89%, respectively. The storage of HM at subzero temperatures at 0.1 MPa did not affect the content of carbohydrates or crude and true protein. For fat and the energy value, significant decreases were observed at -5 °C after 90 days of storage.


Assuntos
Armazenamento de Alimentos , Lactoferrina , Leite Humano , Muramidase , Valor Nutritivo , Humanos , Leite Humano/química , Lactoferrina/análise , Armazenamento de Alimentos/métodos , Muramidase/análise , Muramidase/metabolismo , Lactalbumina/análise , Imunoglobulina A Secretora/análise , Imunoglobulina A Secretora/metabolismo , Nutrientes/análise , Proteínas do Leite/análise , Feminino
14.
J Phys Chem B ; 128(20): 4922-4930, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38733344

RESUMO

The disaccharide trehalose is generally acknowledged as a superior stabilizer of proteins and other biomolecules in aqueous environments. Despite many theories aiming to explain this, the stabilization mechanism is still far from being fully understood. This study compares the stabilizing properties of trehalose with those of the structurally similar disaccharide sucrose. The stability has been evaluated for the two proteins, lysozyme and myoglobin, at both low and high temperatures by determining the glass transition temperature, Tg, and the denaturation temperature, Tden. The results show that the sucrose-containing samples exhibit higher Tden than the corresponding trehalose-containing samples, particularly at low water contents. The better stabilizing effect of sucrose at high temperatures may be explained by the fact that sucrose, to a greater extent, binds directly to the protein surface compared to trehalose. Both sugars show Tden elevation with an increasing sugar-to-protein ratio, which allows for a more complete sugar shell around the protein molecules. Finally, no synergistic effects were found by combining trehalose and sucrose. Conclusively, the exact mechanism of protein stabilization may vary with the temperature, as influenced by temperature-dependent interactions between the protein, sugar, and water. This variability can make trehalose to a superior stabilizer under some conditions and sucrose under others.


Assuntos
Varredura Diferencial de Calorimetria , Muramidase , Mioglobina , Sacarose , Trealose , Trealose/química , Sacarose/química , Muramidase/química , Muramidase/metabolismo , Mioglobina/química , Estabilidade Proteica , Animais , Temperatura
15.
Molecules ; 29(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731411

RESUMO

Fullerenes, particularly C60, exhibit unique properties that make them promising candidates for various applications, including drug delivery and nanomedicine. However, their interactions with biomolecules, especially proteins, remain not fully understood. This study implements both explicit and implicit C60 models into the UNRES coarse-grained force field, enabling the investigation of fullerene-protein interactions without the need for restraints to stabilize protein structures. The UNRES force field offers computational efficiency, allowing for longer timescale simulations while maintaining accuracy. Five model proteins were studied: FK506 binding protein, HIV-1 protease, intestinal fatty acid binding protein, PCB-binding protein, and hen egg-white lysozyme. Molecular dynamics simulations were performed with and without C60 to assess protein stability and investigate the impact of fullerene interactions. Analysis of contact probabilities reveals distinct interaction patterns for each protein. FK506 binding protein (1FKF) shows specific binding sites, while intestinal fatty acid binding protein (1ICN) and uteroglobin (1UTR) exhibit more generalized interactions. The explicit C60 model shows good agreement with all-atom simulations in predicting protein flexibility, the position of C60 in the binding pocket, and the estimation of effective binding energies. The integration of explicit and implicit C60 models into the UNRES force field, coupled with recent advances in coarse-grained modeling and multiscale approaches, provides a powerful framework for investigating protein-nanoparticle interactions at biologically relevant scales without the need to use restraints stabilizing the protein, thus allowing for large conformational changes to occur. These computational tools, in synergy with experimental techniques, can aid in understanding the mechanisms and consequences of nanoparticle-biomolecule interactions, guiding the design of nanomaterials for biomedical applications.


Assuntos
Fulerenos , Simulação de Dinâmica Molecular , Muramidase , Ligação Proteica , Fulerenos/química , Muramidase/química , Muramidase/metabolismo , Sítios de Ligação , Proteínas de Ligação a Tacrolimo/química , Proteínas de Ligação a Tacrolimo/metabolismo , Proteínas de Ligação a Ácido Graxo/química , Proteínas de Ligação a Ácido Graxo/metabolismo , Proteínas/química , Proteínas/metabolismo , Protease de HIV
16.
Gut Microbes ; 16(1): 2355693, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38780487

RESUMO

Chemotherapy remains a major treatment for malignant tumors, yet the application of standard dose intensity chemotherapy is limited due to the side effects of cytotoxic drugs, especially in old populations. The underlying mechanisms of cytotoxicity and strategies to increase the safety and tolerance of chemotherapy remain to be explored. Using 5-fluorouracil (5-FU), a cornerstone chemotherapeutic drug, we demonstrate that the main cause of death in ad libitum (AL) fed mice after 5-FU chemotherapy was infection caused by translocation of intestinal opportunistic pathogens. We show that these opportunistic pathogens greatly increase in the intestine after chemotherapy, which was closely related to loss of intestinal lysozyme. Of note, two weeks of dietary restriction (DR) prior to chemotherapy significantly protected the loss of lysozyme and increased the content of the beneficial Lactobacillus genera, resulting in a substantial inhibition of intestinal opportunistic pathogens and their translocation. The rescue effect of DR could be mimicked by Lysozyme or Lactobacillus gavage. Our study provides the first evidence that DR achieved a comprehensive protection of the intestinal physical, biological and chemical barriers, which significantly improved the overall survival of 5-FU-treated mice. Importantly, the above findings were more prominent in old mice. Furthermore, we show that patients over 65 years old have enriched opportunistic pathogens in their gut microbiota, especially after 5-FU based chemotherapy. Our study reveals important mechanisms for the poor chemotherapy tolerance of the elderly population, which can be significantly improved by short-term DR. This study generates new insights into methods for improving the chemotherapeutic prognosis by increasing the chemotherapy tolerance and safety of patients with malignant tumors.


Assuntos
Translocação Bacteriana , Fluoruracila , Microbioma Gastrointestinal , Intestinos , Animais , Camundongos , Translocação Bacteriana/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Intestinos/microbiologia , Intestinos/efeitos dos fármacos , Muramidase/metabolismo , Restrição Calórica , Camundongos Endogâmicos C57BL , Masculino , Lactobacillus , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Bactérias/classificação , Feminino , Infecções Oportunistas/microbiologia , Infecções Oportunistas/prevenção & controle , Infecções Oportunistas/tratamento farmacológico
17.
Dalton Trans ; 53(21): 9001-9010, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38726661

RESUMO

Cyclometallated Pt(II) complexes possessing hydrophobic 2-phenylpyridine (ppy) ligands and hydrophilic acetonylacetone (acac) ligands have been investigated for their ability to detect amyloid fibrils via luminescence response. Using hen egg-white lysozyme (HEWL) as a model amyloid protein, Pt(II) complexes featuring benzanilide-substituted ppy ligands and ethylene glycol-functionalized acac ligands demonstrated enhanced luminescence in the presence of HEWL fibrils, whereas Pt(II) complexes lacking complementary hydrophobic/hydrophilic ligand sets displayed little to no emission enhancement. An amphiphilic Pt(II) complex incorporating a bis(ethylene glycol)-derivatized acac ligand was additionally found to trigger restructuring of HEWL fibrils into smaller spherical aggregates. Amphiphilic Pt(II) complexes were generally non-toxic to SH-SY5Y neuroblastoma cells, and several complexes also exhibited enhanced luminescence in the presence of Aß42 fibrils associated with Alzheimer's disease. This study demonstrates that easily prepared and robust (ppy)PtII(acac) complexes show promising reactivity toward amyloid fibrils and represent attractive molecular scaffolds for design of small-molecule probes targeting amyloid assemblies.


Assuntos
Amiloide , Muramidase , Humanos , Amiloide/química , Amiloide/metabolismo , Muramidase/química , Muramidase/metabolismo , Linhagem Celular Tumoral , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Luminescência , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/química , Animais , Interações Hidrofóbicas e Hidrofílicas , Agregados Proteicos/efeitos dos fármacos , Platina/química , Compostos Organoplatínicos/química , Compostos Organoplatínicos/farmacologia , Compostos Organoplatínicos/síntese química , Ligantes , Tensoativos/química , Tensoativos/síntese química
18.
Colloids Surf B Biointerfaces ; 238: 113928, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692175

RESUMO

In this research, four water-insoluble flavonoid compounds were utilized and reacted with arginine to prepare four carbonized polymer dots with good water-solubility in a hydrothermal reactor. Structural characterization demonstrated that the prepared carbonized polymer dots were classic core-shell structure. Effect of the prepared carbonized polymer dots on protein amyloid aggregation was further investigated using hen egg white lysozyme and human lysozyme as model protein in aqueous solution. All of the prepared carbonized polymer dots could retard the amyloid aggregation of hen egg white lysozyme and human lysozyme in a dose-depended manner. All measurements displayed that the inhibition ratio of luteolin-derived carbonized polymer dots (CPDs-1) was higher than that of the other three carbonized polymer dots under the same dosage. This result may be interpreted by the highest content of phenolic hydroxyl groups on the periphery. The inhibition ratio of CPDs-1 on hen egg white lysozyme and human lysozyme reached 88 % and 83 % at the concentration of 0.5 mg/mL, respectively. CPDs-1 also could disaggregate the formed mature amyloid fibrils into short aggregates.


Assuntos
Amiloide , Flavonoides , Muramidase , Polímeros , Agregados Proteicos , Muramidase/química , Muramidase/metabolismo , Humanos , Polímeros/química , Polímeros/farmacologia , Amiloide/química , Amiloide/antagonistas & inibidores , Flavonoides/química , Flavonoides/farmacologia , Agregados Proteicos/efeitos dos fármacos , Animais , Galinhas , Carbono/química
19.
J Phys Chem Lett ; 15(20): 5543-5548, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38752860

RESUMO

Protein dynamics display distinct traits that are linked to their specific biological function. However, the interplay between intrinsic dynamics and the molecular environment on protein stability remains poorly understood. In this study, we investigate, by incoherent neutron scattering, the subnanosecond time scale dynamics of three model proteins: the mesophilic lysozyme, the thermophilic thermolysin, and the intrinsically disordered ß-casein. Moreover, we address the influence of water, glycerol, and glucose, which create progressively more viscous matrices around the protein surface. By comparing the protein thermal fluctuations, we find that the internal dynamics of thermolysin are less affected by the environment compared to lysozyme and ß-casein. We ascribe this behavior to the protein dynamic personality, i.e., to the stiffer dynamics of the thermophilic protein that contrasts the influence of the environment. Remarkably, lysozyme and thermolysin in all molecular environments reach a critical common flexibility when approaching the calorimetric melting temperature.


Assuntos
Caseínas , Muramidase , Termolisina , Muramidase/química , Muramidase/metabolismo , Termolisina/química , Termolisina/metabolismo , Caseínas/química , Glicerol/química , Água/química , Glucose/química , Difração de Nêutrons , Simulação de Dinâmica Molecular
20.
ACS Appl Mater Interfaces ; 16(20): 25740-25756, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38722759

RESUMO

Micro- and nano-plastics (NPs) are found in human milk, blood, tissues, and organs and associate with aberrant health outcomes including inflammation, genotoxicity, developmental disorders, onset of chronic diseases, and autoimmune disorders. Yet, interfacial interactions between plastics and biomolecular systems remain underexplored. Here, we have examined experimentally, in vitro, in vivo, and by computation, the impact of polystyrene (PS) NPs on a host of biomolecular systems and assemblies. Our results reveal that PS NPs essentially abolished the helix-content of the milk protein ß-lactoglobulin (BLG) in a dose-dependent manner. Helix loss is corelated with the near stoichiometric formation of ß-sheet elements in the protein. Structural alterations in BLG are also likely responsible for the nanoparticle-dependent attrition in binding affinity and weaker on-rate constant of retinol, its physiological ligand (compromising its nutritional role). PS NP-driven helix-to-sheet conversion was also observed in the amyloid-forming trajectory of hen egg-white lysozyme (accelerated fibril formation and reduced helical content in fibrils). Caenorhabditis elegans exposed to PS NPs exhibited a decrease in the fluorescence of green fluorescent protein-tagged dopaminergic neurons and locomotory deficits (akin to the neurotoxin paraquat exposure). Finally, in silico analyses revealed that the most favorable PS/BLG docking score and binding energies corresponded to a pose near the hydrophobic ligand binding pocket (calyx) of the protein where the NP fragment was found to make nonpolar contacts with side-chain residues via the hydrophobic effect and van der Waals forces, compromising side chain/retinol contacts. Binding energetics indicate that PS/BLG interactions destabilize the binding of retinol to the protein and can potentially displace retinol from the calyx region of BLG, thereby impairing its biological function. Collectively, the experimental and high-resolution in silico data provide new insights into the mechanism(s) by which PS NPs corrupt the bimolecular structure and function, induce amyloidosis and onset neuronal injury, and drive aberrant physiological and behavioral outcomes.


Assuntos
Caenorhabditis elegans , Lactoglobulinas , Muramidase , Animais , Muramidase/química , Muramidase/metabolismo , Lactoglobulinas/química , Lactoglobulinas/metabolismo , Caenorhabditis elegans/metabolismo , Poliestirenos/química , Nanopartículas/química , Vitamina A/química , Vitamina A/metabolismo , Humanos , Homeostase/efeitos dos fármacos , Plásticos/química
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