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1.
Artigo em Inglês | MEDLINE | ID: mdl-38460447

RESUMO

Human serum albumin (HSA) is known to undergo modifications by glucose during diabetes. This process produces glycated HSA that can have altered binding to some drugs. In this study, high-performance affinity microcolumns and competition studies were used to see how glycation affects the binding by two thiazolidinedione-class drugs (i.e., pioglitazone and rosiglitazone) at specific regions of HSA. These regions included Sudlow sites I and II, the tamoxifen and digitoxin sites, and a drug-binding site located in subdomain IB. At Sudlow site II, the association equilibrium constants (or binding constants) for pioglitazone and rosiglitazone with normal HSA were 1.7 × 105 M-1 and 2.0 × 105 M-1 at pH 7.4 and 37 °C, with values that changed by up to 5.7-fold for glycated HSA. Sudlow site I of normal HSA had binding constants for pioglitazone and rosiglitazone of 3.4 × 105 M-1 and 4.6 × 105 M-1, with these values changing by up to 1.5-fold for glycated HSA. Rosiglitazone was found to also bind a second region that had a positive allosteric effect on Sudlow site I for all the tested preparations of HSA (binding affinity, 1.1-3.2 × 105 M-1; coupling constant for Sudlow site I, 1.20-1.34). Both drugs had a strong positive allosteric effect on the tamoxifen site of HSA (coupling constants, 13.7-19.9 for pioglitazone and 3.7-11.5 for rosiglitazone). Rosiglitazone also had weak interactions at a site in subdomain IB, with a binding constant of 1.4 × 103 M-1 for normal HSA and a value that was altered by up to 6.8-fold with glycated HSA. Neither of the tested drugs had any significant binding at the digitoxin site. The results were used to produce affinity maps that described binding by these thiazolidinediones with HSA and the effects of glycation on these interactions during diabetes.


Assuntos
Diabetes Mellitus , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/química , Hipoglicemiantes/química , Reação de Maillard , Rosiglitazona , Pioglitazona , Ligação Proteica , Albumina Sérica/química , Tamoxifeno , Digitoxina , Cromatografia de Afinidade/métodos , Sítios de Ligação
2.
Biotechnol J ; 19(3): e2300502, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38479996

RESUMO

The anti-inflammatory effect of α-melanocyte-stimulating hormone (α-MSH) in the central nervous system (CNS) has been reported for 40 years. However, the short half-life of α-MSH limits its clinical applications. The previous study has shown that a fusion protein comprising protein transduction domain (PTD), human serum albumin (HSA), and α-MSH extends the half-life of α-MSH, but its anti-inflammatory effect is not satisfactory. In this study, optimization of the structures of fusion proteins was attempted by changing the linker peptide between HSA and α-MSH. The optimization resulted in the improvement of various important characteristics, especially the stability and anti-inflammatory bioactivity, which are important features in protein medicines. Compared to the original linker peptide L0, the 5-amino-acid rigid linker peptide L6 (PAPAP) is the best option for further investigation due to its higher expression (increased by 6.27%), improved purification recovery (increased by 60.8%), excellent thermal stability (Tm = 83.5°C) and better inhibition in NF-κB expression (increased by 81.5%). From this study, the significance of the design of linker peptides in the study of structure-activity relationship of fusion proteins was proved.


Assuntos
Albumina Sérica Humana , alfa-MSH , Humanos , alfa-MSH/farmacologia , NF-kappa B/metabolismo , Anti-Inflamatórios/farmacologia
3.
Sci Rep ; 14(1): 5946, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467715

RESUMO

The use of dendrimers as drug and nucleic acid delivery systems requires knowledge of their interactions with objects on their way to the target. In the present work, we investigated the interaction of a new class of carbosilane dendrimers functionalized with polyphenolic and caffeic acid residues with human serum albumin, which is the most abundant blood protein. The addition of dendrimers to albumin solution decreased the zeta potential of albumin/dendrimer complexes as compared to free albumin, increased density of the fibrillary form of albumin, shifted fluorescence spectrum towards longer wavelengths, induced quenching of tryptophan fluorescence, and decreased ellipticity of circular dichroism resulting from a reduction in the albumin α-helix for random coil structural form. Isothermal titration calorimetry showed that, on average, one molecule of albumin was bound by 6-10 molecules of dendrimers. The zeta size confirmed the binding of the dendrimers to albumin. The interaction of dendrimers and albumin depended on the number of caffeic acid residues and polyethylene glycol modifications in the dendrimer structure. In conclusion, carbosilane polyphenolic dendrimers interact with human albumin changing its structure and electrical properties. However, the consequences of such interaction for the efficacy and side effects of these dendrimers as drug/nucleic acid delivery system requires further research.


Assuntos
Ácidos Cafeicos , Dendrímeros , Ácidos Nucleicos , Humanos , Albumina Sérica Humana/metabolismo , Dendrímeros/química , Silanos/química
4.
ACS Appl Mater Interfaces ; 16(9): 11206-11216, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38391265

RESUMO

Plasma protein therapies are used by millions of people across the globe to treat a litany of diseases and serious medical conditions. One challenge in the manufacture of plasma protein therapies is the removal of salt ions (e.g., sodium, phosphate, and chloride) from the protein solution. The conventional approach to remove salt ions is the use of diafiltration membranes (e.g., tangential flow filtration) and ion-exchange chromatography. However, the ion-exchange resins within the chromatographic column as well as filtration membranes are subject to fouling by the plasma protein. In this work, we investigate the membrane capacitive deionization (MCDI) as an alternative separation platform for removing ions from plasma protein solutions with negligible protein loss. MCDI has been previously deployed for brackish water desalination, nutrient recovery, mineral recovery, and removal of pollutants from water. However, this is the first time this technique has been applied for removing 28% of ions (sodium, chloride, and phosphate) from human serum albumin solutions with less than 3% protein loss from the process stream. Furthermore, the MCDI experiments utilized highly conductive poly(phenylene alkylene)-based ion exchange membranes (IEMs). These IEMs combined with ionomer-coated nylon meshes in the spacer channel ameliorate Ohmic resistances in MCDI improving the energy efficiency. Overall, we envision MCDI as an effective separation platform in biopharmaceutical manufacturing for deionizing plasma protein solutions and other pharmaceutical formulations without a loss of active pharmaceutical ingredients.


Assuntos
Carbono , Purificação da Água , Humanos , Carbono/química , Cloretos , Cloreto de Sódio/química , Albumina Sérica Humana , Sódio , Fosfatos , Eletrodos , Purificação da Água/métodos , Adsorção
5.
Phys Chem Chem Phys ; 26(10): 8528-8538, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38411624

RESUMO

Oxidative stress, generated by reactive oxygen species (ROS), is responsible for the loss of structure and functionality of proteins and is associated with several aging-related diseases. Here, we report an in vitro study to gauge the effect of ROS on the structural rearrangement of human serum albumin (HSA), a plasma protein, through metal-catalyzed oxidation (MCO) at physiological temperature through various biophysical techniques like UV-vis absorption, circular dichroism (CD), differential scanning calorimetry (DSC), MALDI-TOF, FTIR, and Raman spectroscopy. The UV-vis spectra of oxidized HSA show an early blueshift, signifying the unfolding of the protein because of ROS followed by the broadening of the absorption peak at a longer time. The DSC data corroborate the observation, revealing an exothermic transition for the oxidized sample at a longer time, suggesting in situ aggregation. The CD and FTIR spectra indicate the associated secondary structural changes occurring with time, depicting the variation of the helical content of HSA. The amide-III analysis of Raman data also complements the structural changes, and MALDI-TOF data show the mass distribution with time. Overall, this work might help determine the effect of oxidation on the biological activity of serum albumin as it can impact the physiological properties of HSA.


Assuntos
Albumina Sérica Humana , Albumina Sérica , Humanos , Albumina Sérica Humana/química , Espécies Reativas de Oxigênio , Albumina Sérica/química , Albumina Sérica/metabolismo , Dicroísmo Circular , Estresse Oxidativo , Ligação Proteica , Espectrometria de Fluorescência
6.
Mikrochim Acta ; 191(3): 151, 2024 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-38386184

RESUMO

A novel luminol derivative of N-(1,4-dioxo-1,2,3,4-tetrahydrophthalazin-5-yl)acrylamide (DTA) with excellent luminescence efficiency was designed and synthesized. Furthermore, a molecularly imprinted electrochemiluminescence sensor (MIECLS) was fabricated to detect ultratrace levels of human serum albumin (HSA) with high sensitivity and selectivity via a click reaction. The molecularly imprinted polymers (MIPs) were formed on the electrode surface via electropolymerization with HSA as a template molecule and catechol as a monomer. In the detection process, the -SH group of HSA on the electrode and the C = C bond of acryloyl group in DTA formed a new C-S bond via the Michael addition reaction to construct the MIECLS. The higher the concentration of HSA, the greater electrochemiluminescence (ECL) intensity measured. Taking advantage of MIECLS for ECL detection (scanning potential, - 0.4 to 0.5 V), there was a good linear relationship between ECL intensity and the logarithm of HSA concentration in the range 5 × 10-9 to 1 × 10-13 mg mL-1. The limit of detection (LOD) of the sensor was 1.05 × 10-15 mg mL-1. The sensor exhibited outstanding selectivity and stability. The sensor was applied to detect HSA in human serum with good recoveries of 97.7-105.2%. The concentration of HSA was detected by electrochemical method using the gating effect of MIP.


Assuntos
Acrilamida , Luminol , Humanos , Técnicas Eletroquímicas , Eletrodos , Albumina Sérica Humana
7.
J Biochem Mol Toxicol ; 38(3): e23664, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38372178

RESUMO

The present work elucidates the role of colchicine (COL) on albumin glycation and cellular oxidative stress in diabetic cardiomyopathy (DCM). Human serum albumin (HSA) was glycated with methylglyoxal in the presence of COL (2.5, 3.75, and 5 µM), whereas positive and negative control samples were maintained separately. The effects of COL on HSA glycation, structural and functional modifications in glycated HSA were analyzed using different spectroscopical and fluorescence techniques. Increased fructosamine, carbonyl, and pentosidine formation in glycated HSA samples were inhibited in the presence of COL. Structural conformation of HSA and glycated HSA samples was examined by field emission scanning electron microscopy, circular dichroism, Fourier transform infrared, and proton nuclear magnetic resonance analyses, where COL maintained both secondary and tertiary structures of HSA against glycation. Functional marker assays included ABTS•+ radical scavenging and total antioxidant activities, advanced oxidative protein product formation, and turbidimetry, which showed preserved functional properties of glycated HSA in COL-containing samples. Afterward, rat cardiomyoblast (H9c2 cell line) was treated with glycated HSA-COL complex (400 µg/mL) for examining various cellular antioxidants (nitric oxide, catalase, superoxide dismutase, and glutathione) and detoxification enzymes (aldose reductase, glyoxalase I, and II) levels. All three concentrations of COL exhibited effective anti-glycation properties, enhanced cellular antioxidant levels, and detoxification enzyme activities. The report comprehensively analyzes the potential anti-glycation and properties of COL during its initial assessment.


Assuntos
Diabetes Mellitus , Cardiomiopatias Diabéticas , Humanos , Animais , Ratos , Produtos Finais de Glicação Avançada/metabolismo , Antioxidantes/metabolismo , Cardiomiopatias Diabéticas/tratamento farmacológico , Reação de Maillard , Glicosilação , Albumina Sérica/metabolismo , Estresse Oxidativo , Albumina Sérica Humana/metabolismo , Dicroísmo Circular
8.
Biol Pharm Bull ; 47(2): 389-393, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38325827

RESUMO

It was recently reported that the dexmedetomidine concentration within the extracorporeal circuit decreases with co-administration of midazolam. In this study, we investigated whether displacement of dexmedetomidine by midazolam from the binding site of major plasma proteins, human serum albumin (HSA) and α1-acid glycoprotein (AAG), would increase levels of free dexmedetomidine that could be adsorbed to the circuit. Equilibrium dialysis experiments indicated that dexmedetomidine binds to a single site on both HSA and AAG with four times greater affinity than midazolam. Midazolam-mediated inhibition of the binding of dexmedetomidine to HSA and AAG was also examined. The binding of dexmedetomidine to these proteins decreased in the presence of midazolam. Competitive binding experiments suggested that the inhibition of binding by midazolam was due to competitive displacement at site II of HSA and due to non-competitive displacement at the site of AAG. Thus, our present data indicate that free dexmedetomidine displaced by midazolam from site II of HSA or from AAG is adsorbed onto extracorporeal circuits, resulting in a change in the dexmedetomidine concentration within the circuit.


Assuntos
Dexmedetomidina , Midazolam , Humanos , Ligação Proteica/fisiologia , Dexmedetomidina/farmacologia , Proteínas Sanguíneas/metabolismo , Orosomucoide/metabolismo , Albumina Sérica Humana/metabolismo
9.
Sci Rep ; 14(1): 3964, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368495

RESUMO

The identification of circulating biomarkers of endothelial dysfunction (ED), a precursor to atherosclerosis, in rheumatoid arthritis (RA) would facilitate early risk stratification and prevention strategies. Ischemia-modified albumin (IMA) has emerged as a potential biomarker of oxidative stress, ischemia, and ED. However, studies examining the relationship between IMA and ED in RA patients are lacking. We measured serum IMA concentrations by using an albumin cobalt binding test and peripheral vasodilatory capacity by EndoPAT in 113 RA patients without previous cardiovascular events enrolled in the EDRA study (ClinicalTrials.gov: NCT02341066). The mean peripheral vasodilatory capacity, expressed by the log of reactive hyperemia index (logRHI), was 0.82, corresponding to 27% RA patients having ED. The mean plasma concentrations of IMA were 0.478 absorbance units. We observed a significant and inverse association between peripheral vasodilatory capacity and serum IMA concentrations (rho = - 0.22, p = 0.02). In univariate logistic regression, ED was significantly associated with serum IMA concentrations [OR 1173 (95% CI 1.3568 to 101,364), p = 0.040) and higher disease activity. In multivariate logistic regression, the independent association between ED and IMA remained significant after correction for disease activity and other RA-confounders [OR 2252 (95% CI 1.0596 to 4,787,505), p = 0.048 in Model 1; OR 7221 (95% CI 4.1539 to 12,552,859), p = 0.02 in Model 2]. Conclusions: This study suggests that IMA is a promising biomarker of ED in RA. Further research is needed to confirm our findings and determine the clinical utility of IMA in detecting and managing early atherosclerosis in RA patients.


Assuntos
Artrite Reumatoide , Aterosclerose , Humanos , Biomarcadores , Albumina Sérica , Albumina Sérica Humana
10.
Phys Chem Chem Phys ; 26(7): 6436-6447, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38317610

RESUMO

Human serum albumin (HSA) is the most prominent protein in blood plasma, responsible for the maintenance of blood viscosity and transport of endogenous and exogenous molecules. Fatty acids (FA) are the most common ligands of HSA and their binding can modify the protein's structure. The protein can assume two well-defined conformations, referred to as 'Neutral' and 'Basic'. The Neutral (N) state occurs at pH close to 7.0 and in the absence of bound FA. The Basic (B) state occurs at pH higher than 8.0 or when the protein is bound to long-chain FA. HSA's allosteric behaviour is dependent on the number on FA bound to the structure. However, the mechanism of this allosteric regulation is not clear. To understand how albumin changes its conformation, we compared a series of HSA structures deposited in the protein data bank to identify the minimum amount of FA bound to albumin, which is enough to drive the allosteric transition. Thereafter, non-biased molecular dynamics (MD) simulations were used to track protein's dynamics. Surprisingly, running an ensemble of relatively short MD simulations, we observed rapid transition from the B to the N state. These simulations revealed differences in the mobilities of the protein's subdomains, with one domain unable to fully complete its transition. To track the transition dynamics in full, we used these results to choose good geometrical collective variables for running metadynamics simulations. The metadynamics calculations showed that there was a low energy barrier for the transition from the B to the N state, while a higher energy barrier was observed for the N to the B transition. These calculations also offered valuable insights into the transition process.


Assuntos
Albumina Sérica Humana , Albumina Sérica , Humanos , Albumina Sérica Humana/metabolismo , Ligação Proteica , Albumina Sérica/química , Albumina Sérica/metabolismo , Ácidos Graxos/química , Termodinâmica , Sítios de Ligação
11.
BMJ Open ; 14(2): e079309, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355195

RESUMO

INTRODUCTION: Human albumin is used in the treatment of complications of cirrhosis. However, the use of long-term human albumin administration is costly and resource demanding for both patients and healthcare systems. A precision medicine approach with biomarkers to predict human albumin treatment response, so-called predictive biomarkers, could make this a viable treatment option in patients with cirrhosis and ascites. METHODS AND ANALYSIS: ALB-TRIAL is a multinational, double-blind, placebo-controlled randomised controlled trial. We aim to validate a predictive biomarker, consisting of a panel of circulating metabolites, to predict the treatment response to human albumin in patients with cirrhosis and ascites. All enrolled patients are stratified into a high-expected or low-expected effect stratum of human albumin based on the biomarker outcome. After stratification, patients in each group are randomised into either active treatment (20% human albumin) or corresponding placebo (0.9% NaCl) every 10th day for 6 months. The primary outcome is the cumulative number of liver-related events (composite of decompensation episodes, transjugular intrahepatic shunt insertion, liver transplantation and death). Key secondary outcomes include time-to-event analysis of primary outcome components, an analysis of the total healthcare burden and a health economic analysis. ETHICS AND DISSEMINATION: The trial obtained ethical and regulatory approval in Denmark, Germany, the Netherlands, Belgium, Hungary and Spain through the Clinical Trials Information System (CTIS) from 13 February 2023, while UK approvals from the Health Regulatory Authority, Medicines and Healthcare products Regulatory Agency and Research Ethics Committee are pending. Findings will be published in peer-reviewed journals, presented at conferences, communicated to relevant stakeholders and in the public registry of CTIS, following trial completion. TRIAL REGISTRATION NUMBER: NCT05056220 EU CT: 2022-501006-34-01.


Assuntos
Transplante de Fígado , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/uso terapêutico , Ascite/terapia , Cirrose Hepática/complicações , Resultado do Tratamento , Biomarcadores , Método Duplo-Cego
12.
Anal Chem ; 96(8): 3498-3507, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38363806

RESUMO

The development of small-molecular fluorogenic tools for the chemo-selective labeling of proteins in live cells is important for the evaluation of intracellular redox homeostasis. Dynamic imaging of human serum albumin (HSA), an antioxidant protein under oxidative stress with concomitant release of antioxidant drugs to maintain redox homeostasis, affords potential opportunities for disease diagnosis and treatment. In this work, we developed a nonfluorogenic prodrug named TPA-NAC, by introducing N-acetyl-l-cysteine (NAC) into a conjugated acceptor skeleton. Through combined thiol and amino addition, coupling with HSA results in fluorescence turn-on and drug release. It was reasoned that the restricted intramolecular motion of the probe under an HSA microenvironment after covalent bonding inhibited the nonradiative transitions. Furthermore, the biocompatibility and photochemical properties of TPA-NAC enabled it to image exogenous and endogenous HSA in living cells in a wash-free manner. Additionally, the released drug evoked upregulation of superoxide dismutase (SOD), which synergistically eliminated reactive oxygen species in a drug-induced liver injury model. This study provides insights into the design of new theranostic fluorescent prodrugs for chemo-selective protein labeling and disease treatments.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Pró-Fármacos , Humanos , Antioxidantes/farmacologia , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Medicina de Precisão , Albumina Sérica/química , Acetilcisteína , Albumina Sérica Humana
13.
Biosens Bioelectron ; 251: 116118, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38382273

RESUMO

Glycated albumin (GA), defined as the percentage of serum albumin glycation, is a mid-term glycemic control marker for diabetes. The concentrations of both glycated human serum albumin (GHSA) and total human serum albumin (HSA) are required to calculate GA. Here, we report the development of a GA sensor employing two albumin aptamers: anti-GHSA aptamer which is specific to GHSA and anti-HSA aptamer which recognizes both glycated and non-glycated HSA. We combine these aptamers with extended gate field effect transistors (EGFETs) to realize GA monitoring without the need to pretreat serum samples, and therefore suitable for point of care and home-testing applications. Using anti-GHSA aptamer-immobilized electrodes and EGFETs, we measured GHSA concentrations between 0.1-10 µM within 20 min. The sensor was able to measure GHSA concentration in the presence of BSA for a range of known GA levels (5-29%). With anti-HSA aptamer-immobilized electrodes and EGFETs, we measured total HSA concentrations from 1-17 µM. Furthermore, GHSA and total HSA concentrations of both healthy and diabetic-level samples were determined with GHSA and HSA sensors. The measured GHSA and total HSA concentrations in three samples were used to determine respective GA percentages, and our calculations agreed with GA levels determined by reference methods. Thus, we developed simple and rapid dual aptamer-based EGFET sensors to monitor GA through measuring GHSA and total HSA concentration, without the need for sample pretreatment, a mandatory step in the current standard of enzymatic GA monitoring.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus , Humanos , Albumina Sérica Glicada , Produtos Finais de Glicação Avançada , Albumina Sérica , Albumina Sérica Humana , Oligonucleotídeos
14.
Biophys Chem ; 307: 107198, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38359582

RESUMO

Wedelolactone (WEL) is a small molecule compound isolated from Eclipta prostrate L., which has been reported to possess various biological activities such as anti-hepatotoxicity, anti-hypertension, anti-tumour, anti-phospholipase A2 and detoxification activity against snake venom. In the present study, we investigated the interaction of WEL with human serum albumin (HSA) using simultaneous fluorescence, UV-visible spectroscopy, 3D fluorescence spectroscopy, Fourier transform infrared spectroscopy (FTIR), molecular docking technique and molecular dynamics simulation. We found that the interaction between HSA and WEL can exhibit a static fluorescence burst mechanism, and the binding process is essentially spontaneous, with the main forces manifested as hydrogen bonding, van der Waals force and electrostatic interactions. Competitive binding and molecular docking studies showed that WEL preferentially bound to HSA in substructural region IIA (site I); molecular dynamics simulations showed that HSA interacted with WEL to form a stable complex, which also induced conformational changes in HSA. The study of the interaction between WEL and HSA can provide a reference for a more in-depth study of the pharmacodynamic mechanism of WEL and its further development and utilisation.


Assuntos
Cumarínicos , Simulação de Dinâmica Molecular , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/química , Simulação de Acoplamento Molecular , Sítios de Ligação , Ligação Proteica , Dicroísmo Circular , Espectrometria de Fluorescência , Termodinâmica
15.
Environ Int ; 184: 108492, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38350258

RESUMO

Water-soluble organic molecules (WSOMs) in inhaled PM2.5 can readily translocate from the lungs into the blood circulation, facilitating their distribution to and health effects on distant organs and tissues in the human body. Human serum albumin (HSA), the most abundant protein carrier in the blood, readily binds exogenous substances to form non-covalent adducts and subsequently transports them throughout the circulatory system, thereby indicating their internal exposure. The direct internal exposure of WSOMs in PM2.5 needs to be understood. In this study, the non-covalent HSA-WSOM adductome was developed as a dosimeter to evaluate the internal exposure potential of WSOMs in urban PM2.5. The WSOM composition was acquired from non-target high-resolution mass spectrometry analysis coupled with multiple ionizations. The binding level of HSA-WSOM non-covalent adducts was obtained from surface plasma resonance. Machine learning combined WSOM composition and the binding level of HSA-WSOM non-covalent adducts to screen bindable (also internalizable) WSOMs. The concentration of WSOM ranged from 4 to 13 µg/m3 during our observation period. Of the 17,513 mass spectral features detected, 9,484 contributed to the non-covalent adductome and possessed the internal exposure potential. 102 major contributors accounted for 90.6 % of the HSA-WSOM binding level. The fraction of internalizable WSOMs in PM2.5 varied from 11.9 % to 61.3 %, averaging 26.2 %. WSOMs that have internal exposure potential were primarily lignin-like and lipid-like substances. The HSA-WSOMs non-covalent adductome represents direct internal exposure potential, which can provide crucial insights into the molecular diagnosis of PM2.5 exposure and precise assessments of PM2.5 health effects.


Assuntos
Material Particulado , Água , Humanos , Material Particulado/análise , Albumina Sérica Humana , Espectrometria de Massas , Aerossóis/análise
16.
Chirality ; 36(2): e23640, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38384157

RESUMO

Propranolol is currently considered as an emerging contaminant in water bodies. In this study, R- and S-propranolol were determined in river samples by electrokinetic chromatography (EKC) using nanodiamonds (NDs) and human serum albumin (HSA) as a pseudo-stationary phase in order to achieve enantioseparation. Previously, river samples were preconcentrated using a column filled with Amberlite® IR-120 and Dowex® 50WX8 resins. The setting up of influential factors such as temperature, voltage, pH, and HSA and NDs concentration is accurately described along this manuscript. A multivariate study and optimization was carried out to obtain the enantioseparation of propranolol (Rs = 2.91), which was reached under the following experimental conditions: voltage of 16 kV, temperature of 16°C, phosphate buffer pH 9.5, NDs of 0.20%, and HSA of 15 µmol l-1 . The recoveries of analytes under optimal conditions were higher than 98%. The limits of detection were 0.85 µg l-1 for R- and S-propranolol. The method was applied to real samples, and the obtained results in three different water sources studied were 1.02, 0.59, and 0.30 µg l-1 for the R-enantiomer and 0.99, 0.54, and 0.28 µg l-1 for the S-enantiomer. The accuracy of the proposed methodology (including bias and precision) has allowed us to propose it as a successful tool for the control of water quality.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Nanodiamantes , Humanos , Propranolol , Albumina Sérica Humana , Rios , Estereoisomerismo , Cromatografia Capilar Eletrocinética Micelar/métodos
17.
Molecules ; 29(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38338399

RESUMO

The interaction between human serum albumin (HSA) and hispidin, a polyketide abundantly present in both edible and therapeutic mushrooms, was explored through multispectral methods, hydrophobic probe assays, location competition trials, and molecular docking simulations. The results of fluorescence quenching analysis showed that hispidin quenched the fluorescence of HSA by binding to it via a static mechanism. The binding of hispidin and HSA was validated further by synchronous fluorescence, three-dimensional fluorescence, and UV/vis spectroscopy analysis. The apparent binding constant (Ka) at different temperatures, the binding site number (n), the quenching constants (Ksv), the dimolecular quenching rate constants (Kq), and the thermodynamic parameters (∆G, ∆H, and ∆S) were calculated. Among these parameters, ∆H and ∆S were determined to be 98.75 kJ/mol and 426.29 J/(mol·K), respectively, both exhibiting positive values. This observation suggested a predominant contribution of hydrophobic forces in the interaction between hispidin and HSA. By employing detergents (SDS and urea) and hydrophobic probes (ANS), it became feasible to quantify alterations in Ka and surface hydrophobicity, respectively. These measurements confirmed the pivotal role of hydrophobic forces in steering the interaction between hispidin and HSA. Site competition experiments showed that there was an interaction between hispidin and HSA molecules at site I, which situates the IIA domains of HSA, which was further confirmed by the molecular docking simulation.


Assuntos
Pironas , Albumina Sérica Humana , Albumina Sérica , Humanos , Albumina Sérica Humana/química , Simulação de Acoplamento Molecular , Albumina Sérica/química , Dicroísmo Circular , Espectrometria de Fluorescência , Sítios de Ligação , Termodinâmica , Ligação Proteica
18.
Environ Pollut ; 346: 123552, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38346633

RESUMO

Elucidation of the aggregation behaviors of gold nanoparticles (AuNPs) in water systems is crucial to understanding their environmental fate and transport as well as human health effects. We investigated the early-stage aggregation kinetics of AuNPs coated by human serum albumin (HSA) protein corona (PC) in NaCl and CaCl2 through time-resolved dynamic light scattering. We found that the aggregation of PC-AuNPs depended on the concerted effects of electrolyte concentration, valence, and HSA concentration. At low HSA concentration (≤0.005 g/L), the aggregation kinetics of PC-AuNPs was similar to that of bare AuNPs due to insignificant HSA adsorption. At intermediate HSA concentrations of 0.025-0.050 g/L, the aggregation of PC-AuNPs was retarded in both electrolytes due to steric repulsive forces imparted by the PCs. Additionally, HSA PCs had a weaker retardation effect on PC-AuNPs aggregation in divalent than in monovalent electrolytes. Quartz crystal microbalance measurements revealed that the presence of Ca2+ promoted additional HSA adsorption on PC-AuNPs likely via -COO-Ca2+ bond, and eventually enhanced the aggregation between PC-AuNPs. High-concentration HSA (>0.5 g/L) resulted in no PC-AuNPs aggregation regardless of electrolyte valence and concentrations. Finally, desorption of HSA barely occurred after adsorption on the gold surface, suggesting that the formation of PC-AuNPs is mostly irreversible.


Assuntos
Nanopartículas Metálicas , Coroa de Proteína , Humanos , Ouro/química , Nanopartículas Metálicas/química , Eletrólitos/química , Albumina Sérica Humana , Cinética
19.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397014

RESUMO

The binding of ubiquitous serum ligands (free fatty acids) to human serum albumin (HSA) or its glycation can affect thiol group reactivity, thus influencing its antioxidant activity. The effects of stearic acid (SA) and glucose binding on HSA structural changes and thiol group content and reactivity were monitored by fluoroscopy and the Ellman method during a 14-day incubation in molar ratios to HSA that mimic pathophysiological conditions. Upon incubation with 5 mM glucose, HSA glycation was the same as HSA without it, in three different HSA:SA molar ratios (HSA:SA-1:1-2-4). The protective effect of SA on the antioxidant property of HSA under different glucose regimes (5-10-20 mM) was significantly affected by molar ratios of HSA:SA. Thiol reactivity was fully restored with 5-20 mM glucose at a 1:1 HSA:SA ratio, while the highest thiol content recovery was in pathological glucose regimes at a 1:1 HSA:SA ratio. The SA affinity for HSA increased significantly (1.5- and 1.3-fold, p < 0.01) with 5 and 10 mM glucose compared to the control. These results deepen the knowledge about the possible regulation of the antioxidant role of HSA in diabetes and other pathophysiological conditions and enable the design of future HSA-drug studies which, in turn, is important for clinicians when designing information-based treatments.


Assuntos
Albumina Sérica Humana , Compostos de Sulfidrila , Humanos , Albumina Sérica Humana/metabolismo , Compostos de Sulfidrila/química , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Ácidos Graxos/metabolismo , Albumina Sérica/metabolismo , Ligação Proteica
20.
Dalton Trans ; 53(11): 4984-5000, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38406993

RESUMO

In this study, we present the synthesis, characterization and in vitro cytotoxicity of six organometallic [Ru(II)(η6-p-cymene)(N,N)Cl]Cl, [Rh(III)(η5-C5Me5)(N,N)Cl]Cl and [Re(I)(CO)3(N,N)Cl] complexes, in which the (N,N) ligands are sterane-based 2,2'-bipyridine derivatives (4-Me-bpy-St-OH, 4-Ph-bpy-St-OH). The solution chemical behavior of the ligands and the complexes was explored by UV-visible spectrophotometry and 1H NMR spectroscopy. The ligands and their Re(I) complexes are neutral at pH = 7.40; this contributes to their highly lipophilic character (log D7.40 > +3). The Ru(II) and Rh(III) half-sandwich complexes are much more hydrophilic, and this property is greatly affected by the actual chloride ion content of the medium. The half-sandwich Ru and Rh complexes are highly stable in 30% (v/v) DMSO/water (<5% dissociation at pH = 7.40); this is further increased in water. The Rh(III)(η5-C5Me5) complexes were characterized by higher water/chloride exchange and pKa constants compared to their Ru(II)(η6-p-cymene) counterparts. The Re(I)(CO)3 complexes are also stable in solution over a wide pH range (2-12) without the release of the bidentate ligand; only the chlorido co-ligand can be replaced with OH- at higher pH values. A comprehensive discussion of the binding affinity of the half-sandwich Ru(II) and Rh(III) complexes toward human serum albumin and calf-thymus DNA is also provided. The Ru(II)(η6-p-cymene) complexes interact with human serum albumin via intermolecular forces, while for the Rh(III)(η5-C5Me5) complexes the coordinative binding mode is suggested as well. They are also able to interact with calf-thymus DNA, most likely via the coordination of the guanine nitrogen. The Ru(II)(η6-p-cymene) complexes were found to be the most promising among the tested compounds as they exhibited moderate-to-strong cytotoxic activity (IC50 = 3-11 µM) in LNCaP as well as in PC3 prostate cells in an androgen receptor-independent manner. They were also significantly cytotoxic in breast and colon adenocarcinoma cancer cell lines and showed good selectivity for cancer cells.


Assuntos
Adenocarcinoma , Antineoplásicos , Neoplasias do Colo , Complexos de Coordenação , Cimenos , Compostos Organometálicos , Rutênio , Humanos , Complexos de Coordenação/química , Linhagem Celular Tumoral , Ligantes , Cloretos/química , Antineoplásicos/química , DNA/química , Albumina Sérica Humana , Água , Rutênio/farmacologia , Rutênio/química , Compostos Organometálicos/farmacologia , Compostos Organometálicos/química
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