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1.
Cells ; 11(9)2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35563866

RESUMO

The absence of a native extracellular matrix and the use of xenogeneic sera are often associated with rapid tenocyte function losses during in vitro culture. Herein, we assessed the influence of different sera (equine serum and foetal bovine serum) on equine tenocyte morphology, viability, metabolic activity, proliferation and protein synthesis as a function of tissue-specific extracellular matrix deposition (induced via macromolecular crowding), aging (passages 3, 6, 9) and time in culture (days 3, 5, 7). In comparison to cells at passage 3, at day 3, in foetal bovine serum and without macromolecular crowding (traditional equine tenocyte culture), the highest number of significantly decreased readouts were observed for cells in foetal bovine serum, at passage 3, at day 5 and day 7 and without macromolecular crowding. Again, in comparison to traditional equine tenocyte culture, the highest number of significantly increased readouts were observed for cells in equine serum, at passage 3 and passage 6, at day 7 and with macromolecular crowding. Our data advocate the use of an allogeneic serum and tissue-specific extracellular matrix for effective expansion of equine tenocytes.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Tenócitos , Animais , Matriz Extracelular/metabolismo , Cavalos , Substâncias Macromoleculares/metabolismo , Soroalbumina Bovina/metabolismo
2.
Carbohydr Res ; 516: 108562, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35500517

RESUMO

A convenient strategy for a 'one-pot' synthesis of neoglycoproteins (NGP) was developed using the myrosinase-glucosinolate couple, a natural enzyme-substrate system. This enzymatic reaction allowed us to generate an isothiocyanate in situ which then reacted with the lysine residues of bovine serum albumin protein (BSA) to produce multivalent neoglycoproteins. Using two models, glucomoringin which is a natural glucosinolate bearing a l-rhamnose unit, and an artificial glucosinolate specifically designed for mannose type lectins, an average of up to 17.8 and 28.7 carbohydrate residues could be respectively grafted onto the BSA protein. This process is comparable to commercial approaches using BSA-ManC without the disadvantage of handling harmful chemical reagents. Lectin binding screening (GLYcoPROFILE®) showed that among all NGPs synthesized, BSA-Man 16 gave similar and in some cases better affinities in comparison with commercial BSA-Manc towards various mannose-specific lectins.


Assuntos
Lectinas de Ligação a Manose , Manose , Glucosinolatos , Glicoproteínas/metabolismo , Glicosídeo Hidrolases , Humanos , Lectinas/química , Manose/metabolismo , Soroalbumina Bovina/metabolismo
3.
Carbohydr Polym ; 290: 119482, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35550770

RESUMO

Immunoglobulin Y (IgY) proves advantageous to IgG in prophylaxis and diagnosis. Quantification of IgY is therefore becoming a topic of interest. Here, we demonstrate a piezoelectric biosensor with carboxymethyl chitosan (CMCS) as the immobilization matrix. Gelation and hydrophilic nature of CMCS are favored to form a crosslinked matrix for antibody immobilization, and a comparison was made between carboxymethyl cellulose (CMC) and CMCS to investigate the benefits of such substitution. Calibration from 500 ng/mL to 200 µg/mL was established in buffer with the detection limit (LOD) down to 270 ng/mL, confirming its feasibility. As-prepared biosensor effectively prevents non-specific binding of bovine serum albumin (BSA) and lysozyme. Each real-time assay took 15 min including sensor regeneration, which can be further reduced to 4 min for signal readout only, ready for both repeated measurements after regeneration and disposable devices. Thus, as-prepared biosensor offers a rapid, label-free and cost-effective approach for IgY quantification.


Assuntos
Técnicas Biossensoriais , Quitosana , Anticorpos , Imunoglobulinas , Soroalbumina Bovina/metabolismo
4.
Epigenomics ; 14(8): 431-449, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35285253

RESUMO

Background: To explore advanced glycation end products (AGEs)-induced m6A modification in fibroblasts and its potential role in photoaging. Methods: We studied m6A modification in AGEs-bovine serum albumin-treated fibroblasts with m6A-mRNA & lncRNA epitranscriptomic microarray and bioinformatics analysis. The m6A modification level was also investigated in skin samples. Results: m6A methylation microarray analysis revealed m6A modification profiles in AGEs-treated fibroblasts. Gene ontology, Kyoto Encyclopedia of Genes and Genomes, protein-protein interaction and competing endogenous RNA network analysis indicated that the genes of differentially methylated mRNAs and lncRNAs were mainly related to inflammation processes. We also found that AGEs-bovine serum albumin dose-dependently increased the m6A level and METTL14 expression in both fibroblasts and sun-exposed skin. Conclusion: Our study provided novel information regarding alterations of m6A modifications in AGEs-induced dermal fibroblasts and potential targets for treatment of photoaging.


Assuntos
Produtos Finais de Glicação Avançada , RNA Longo não Codificante , Envelhecimento da Pele , Fibroblastos/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Humanos , Metiltransferases , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Mensageiro/genética , Soroalbumina Bovina/metabolismo , Pele/metabolismo
5.
Luminescence ; 37(4): 633-641, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35102681

RESUMO

In the present work, an improved class of protein functionalized fluorescent 2D Ti3 C2 MXene quantum dots (MXene QDs) was prepared using a hydrothermal method. Exfoliated 2D Ti3 C2 sheets were used as the starting precursor and transport protein bovine serum albumin (BSA) was used to functionalize the MXene QDs. BSA-functionalized MXene QDs exhibited excellent photophysical property and stability at various physiological parameters. High-resolution transmission electron microscopy analysis showed that the BSA@MXene QDs were quasispherical in shape with a size of ~2 nm. The fluorescence intensity of BSA@MXene QDs was selectively quenched in the presence of Fe3+ ions. The mechanism of fluorescence quenching was further substantiated using time-resolved fluorescence and Stern-Volmer analysis. The sensing assay showed a linear response within the concentration range 0-150 µM of Fe3+ ions with excellent limit of detection. BSA@MXene QDs probe showed good selectivity toward ferric ions even in the presence of other potential interferences. The practical applicability of BSA@MXene QDs was further tested in real samples for Fe3+ ion quantification and the sensor had good recovery rates. The cytotoxicity studies of the BSA@MXene QDs toward the human glioblastoma cells revealed that BSA@MXene QDs are biocompatible at lower doses and showed significant cytotoxicity at higher dosages.


Assuntos
Pontos Quânticos , Corantes Fluorescentes , Humanos , Íons , Pontos Quânticos/toxicidade , Soroalbumina Bovina/metabolismo , Titânio
6.
Mar Drugs ; 20(2)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35200624

RESUMO

This study aimed to investigate the influence of kappa (κ)-carrageenan on the initial stages of the foreign body response against pectin gel. Pectin-carrageenan (P-Car) gel beads were prepared from the apple pectin and κ-carrageenan using gelling with calcium ions. The inclusion of 0.5% κ-carrageenan (Car0.5) in the 1.5 (P1.5) and 2% pectin (P2) gel formulations decreased the gel strength by 2.5 times. Car0.5 was found to increase the swelling of P2 gel beads in the cell culture medium. P2 gel beads adsorbed 30-42 mg/g of bovine serum albumin (BSA) depending on pH. P2-Car0.2, P2-Car0.5, and P1.5-Car0.5 beads reduced BSA adsorption by 3.1, 5.2, and 4.0 times compared to P2 beads, respectively, at pH 7. The P1.5-Car0.5 beads activated complement and induced the haemolysis less than gel beads of pure pectin. Moreover, P1.5-Car0.5 gel beads allowed less adhesion of mouse peritoneal macrophages, TNF-α production, and NF-κB activation than the pure pectin gel beads. There were no differences in TLR4 and ICAM-1 levels in macrophages treated with P and P-Car gel beads. P2-Car0.5 hydrogel demonstrated lower adhesion to serous membrane than P2 hydrogel. Thus, the data obtained indicate that the inclusion of κ-carrageenan in the apple pectin gel improves its biocompatibility.


Assuntos
Carragenina/química , Macrófagos Peritoneais/metabolismo , Pectinas/química , Soroalbumina Bovina/metabolismo , Adsorção , Animais , Géis , Hemólise/efeitos dos fármacos , Humanos , Hidrogéis , Concentração de Íons de Hidrogênio , Masculino , Malus , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
7.
Int J Mol Sci ; 23(4)2022 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-35216181

RESUMO

Resistance to antifungal therapy of Candida albicans and non-albicans Candida strains, frequently associated with oral candidosis, is on the rise. In this context, host-defense peptides have emerged as new promising candidates to overcome antifungal resistance. Thus, the aim of this study was to assess the effectiveness against Candida species of different Catestatin-derived peptides, as well as the combined effect with serum albumin. Among Catestatin-derived peptides, the most active against sensitive and resistant strains of C. albicans, C. tropicalis and C. glabrata was the D-isomer of Cateslytin (D-bCtl) whereas the efficiency of the L-isomer (L-bCtl) significantly decreases against C. glabrata strains. Images obtained by transmission electron microscopy clearly demonstrated fungal membrane lysis and the leakage of the intracellular material induced by the L-bCtl and D-bCtl peptides. The possible synergistic effect of albumin on Catestatin-derived peptides activity was investigated too. Our finding showed that bovine serum albumin (BSA) when combined with the L- isomer of Catestatin (L-bCts) had a synergistic effect against Candida albicans especially at low concentrations of BSA; however, no synergistic effect was detected when BSA interacted with L-bCtl, suggesting the importance of the C-terminal end of L-bCts (GPGLQL) for the interaction with BSA. In this context in vitro D-bCtl, as well as the combination of BSA with L-bCts are potential candidates for the development of new antifungal drugs for the treatment of oral candidosis due to Candida and non-Candida albicans, without detrimental side effects.


Assuntos
Candidíase Bucal/tratamento farmacológico , Cromogranina A/farmacologia , Fragmentos de Peptídeos/farmacologia , Peptídeos/farmacologia , Animais , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/metabolismo , Candidíase Bucal/metabolismo , Bovinos , Farmacorresistência Fúngica/efeitos dos fármacos , Humanos , Soroalbumina Bovina/metabolismo
8.
Int J Mol Sci ; 23(3)2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-35163152

RESUMO

Advanced glycation end products (AGEs) are associated with diabetes and its complications. AGEs are formed by the non-enzymatic reactions of proteins and reducing sugars, such as glucose and ribose. Ribose is widely used in glycation research as it generates AGEs more rapidly than glucose. This study analyzed the AGE structures generated from ribose-modified protein by liquid chromatography-quadrupole time-of-flight mass spectrometry. Among these AGEs, Nδ-(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine (MG-H1) was the most abundant in ribose-glycated bovine serum albumin (ribated-BSA) among others, such as Nε-(carboxymethyl) lysine, Nε-(carboxyethyl) lysine, and Nω-(carboxymethyl) arginine. Surprisingly, MG-H1 was produced by ribated-BSA in a time-dependent manner, whereas methylglyoxal levels (MG) were under the detectable level. In addition, Trapa bispinosa Roxb. hot water extract (TBE) possesses several anti-oxidative compounds, such as ellagic acid, and has been reported to inhibit the formation of MG-H1 in vivo. Thus, we evaluated the inhibitory effects of TBE on MG-H1 formation using ribose- or MG-modified proteins. TBE inhibited MG-H1 formation in gelatin incubated with ribose and ribated-BSA, but not in MG-modified gelatin. Furthermore, MG-H1 formation was inhibited by diethylenetriaminepentaacetic acid. These results demonstrated that ribose reacts with proteins to generate Amadori compounds and form MG-H1 via oxidation.


Assuntos
Imidazóis/química , Ornitina/análogos & derivados , Processamento de Proteína Pós-Traducional , Ribose/química , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Animais , Bovinos , Gelatina/química , Glicosilação , Imidazóis/metabolismo , Ornitina/química , Ornitina/metabolismo , Oxirredução , Aldeído Pirúvico/química
9.
Toxicol In Vitro ; 80: 105325, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35121064

RESUMO

Mitochondria are at the core of cellular energy metabolism and are also involved in the oxidative stress response and programmed cell death pathways. Mitochondrial dysfunction is found to be associated with many disease conditions like metabolic syndrome, neurodegenerative disorders, coronary artery diseases, cancer, etc. This has generated considerable interest in the scientific community over the assessment of mitochondrial function and mitochondrial damage. One of the most common methodologies in these studies is by analysing the mitochondrial activity in the presence of mitochondrial substrates, inhibitors and uncouplers. Apart from the specific effects of these molecules on mitochondria, their interactions with the components of the experimental system could interfere with the results derived. Therefore, the role some specific experimental conditions would have on the outcome should be carefully elucidated. Fetal Bovine Serum or Bovine Serum Albumin (BSA); routinely used in in vitro experiments for their growth promoting and surfactant properties; can have profound impact on the pharmacokinetics of chemical compounds as albumin residue can bind to and affect their bioavailability. In the present study, we demonstrate that Carbonyl cyanide 3-chlorophenylhydrazone (CCCP) induced mitochondrial depolarization is hindered in the presence of albumin due to the molecular interaction between CCCP and albumin.


Assuntos
Carbonil Cianeto m-Clorofenil Hidrazona/toxicidade , Mitocôndrias/efeitos dos fármacos , Desacopladores/toxicidade , Animais , Linhagem Celular , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Ratos , Soroalbumina Bovina/metabolismo
10.
Food Chem ; 377: 131945, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-34999459

RESUMO

The present study investigated the effect of pulsed electric field (PEF) pretreatment on the interaction between bovine serum albumin (BSA) and curcumin. Fluorescence quenching results showed that proper PEF pretreatment significantly increased the binding affinity of curcumin and BSA, the binding constant increased by 6.77 times under the conditions of 15 kV/cm for 0.51 ms. However, at higher PEF strength (≥25 kV/cm) and longer processing time (≥0.68 ms), the binding affinity was weakened. PEF pretreatment made the protein structure more disordered and induced partial unfolding of BSA, exposing more hydrophobic regions, thereby increasing the binding affinity to curcumin. PEF-treated BSA (PBSA) possessed better encapsulation efficiency (95.19%) and loading capacity (5.25 mg/g) for curcumin, and the storage stability of curcumin were enhanced by the formation of a complex with PBSA. This study provides new insights into the design of BSA-based delivery systems for curcumin and other hydrophobic nutrients.


Assuntos
Curcumina , Soroalbumina Bovina , Eletricidade , Interações Hidrofóbicas e Hidrofílicas , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência
11.
Biochem Biophys Res Commun ; 592: 1-6, 2022 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-35007844

RESUMO

Currently, semiconductor nanoparticles known as quantum dots (QDs) have attracted interest in various application fields such as those requiring sensing properties, binding assays, and cellular imaging and are the very important in the acceleration of drug discovery due to their unique photophysical properties. Here, we applied graphene quantum dots (GQDs) for the binding assay of membrane progesterone receptor alpha (mPRα), one of the probable membrane receptors that have potential in drug discovery applications. By coupling the amino groups of mPRα with GQDs, we prepared fluorogenic GQD-conjugated mPRα (GQD-mPRα). When mixed with a progesterone-BSA-fluorescein isothiocyanate conjugate (P4-BSA-FITC) to check the ligand receptor binding activity of GQD-mPRα, fluorescence at 520 nm appeared. The fluorescence at 520 nm was reduced by the addition of free progesterone into the reaction mixture. GQD-coupled BSA (GQD-BSA) did not show a reduction in fluorescence at 520 nm. The results demonstrated the formation of a complex of GQD-mPRα and P4-BSA-FITC with ligand receptor binding. We established a ligand binding assay for membrane steroid receptors that is applicable for high-throughput assays.


Assuntos
Bioensaio/métodos , Grafite/química , Pontos Quânticos/química , Receptores de Progesterona/metabolismo , Esteroides/metabolismo , Fluoresceína-5-Isotiocianato/metabolismo , Fluorescência , Humanos , Modelos Moleculares , Progesterona/metabolismo , Receptores de Progesterona/química , Soroalbumina Bovina/metabolismo
12.
J Diabetes Investig ; 13(6): 955-964, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35098679

RESUMO

AIMS/INTRODUCTION: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been shown to display excellent renoprotective effects in diabetic kidney disease with macroalbuminuria/proteinuria. Regarding the renoprotective mechanism of SGLT2i, a sophisticated hypothesis was made by explaining the suppression of glomerular hypertension/hyperfiltration through the adenosine/adenosine type 1 receptor (A1R) signaling-mediated restoration of the tubuloglomerular feedback mechanism; however, how such A1R signaling is relevant for renoprotection by SGLT2i in diabetic kidney disease with proteinuria has not been elucidated. MATERIALS AND METHODS: Streptozotocin-induced diabetic CD-1 mice were injected with bovine serum albumin (BSA) and treated with SGLT2i in the presence/absence of A1R inhibitor administration. RESULTS: We found that the influences of SGLT2i are essentially independent of the activation of A1R signaling in the kidney of BSA-overloaded streptozotocin-induced diabetic mice. BSA-overloaded diabetic mice showed the trend of kidney damage with higher glomerular filtration rate (GFR) and the significant induction of fibrogenic genes, such as transforming growth factor-ß2 and collagen type III. SGLT2i TA-1887 suppressed diabetes-induced GFR in BSA-overloaded diabetic mice was associated with the significant suppression of transforming growth factor-ß2 and collagen type III; A1R-specific inhibitor 8-cyclopentyl-1,3-dipropylxanthine did not cancel the effects of TA-1887 on either GFR or associated gene levels. Both TA-1887 and 8-cyclopentyl-1,3-dipropylxanthine-treated BSA-overloaded diabetic mice showed suppressed glycated hemoglobin levels associated with the increased food intake. When analyzing the association among histological evaluation, GFR and potential fibrogenic gene levels, each group of mice showed distinct correlation patterns. CONCLUSIONS: A1R signaling activation was not the dominant mechanism on the influence of SGLT2i in the kidney of BSA-overloaded diabetic mice.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Receptores Purinérgicos P1/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose , Adenosina/metabolismo , Adenosina/farmacologia , Animais , Colágeno Tipo III/metabolismo , Colágeno Tipo III/farmacologia , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/metabolismo , Glucose/metabolismo , Humanos , Rim , Camundongos , Proteinúria/metabolismo , Soroalbumina Bovina/metabolismo , Soroalbumina Bovina/farmacologia , Transdução de Sinais , Sódio/metabolismo , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Estreptozocina , Fatores de Crescimento Transformadores/metabolismo , Fatores de Crescimento Transformadores/farmacologia
13.
Chem Biol Interact ; 351: 109750, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34813780

RESUMO

We have previously synthesized and characterized the chrysin coordination complex with the oxidovanadium(IV) cation (VIVO(chrys)2) and characterized in ethanolic solution and in solid state. Because suitable single crystals for X-ray diffraction determinations could not be obtained, in the present work, we elucidate the geometrical parameters of this complex by computational methodologies. The optimization and vibrational investigation were carried out both in ethanolic solution and in gas phase. The computational results support the experimentally proposed geometries of the VIVO(chrys)2 complex, thus leading to the conclusion that the complex exists as conformers with trans-octahedral geometry in ethanolic solution and as conformers with cis-octahedral geometry in the solid state. The complex also exists as conformers with trans-octahedral geometry in aqueous media. The active species formed after dissolution in DMSO showed anticancer and antimetastatic behavior in human lung cell line A549 with moderate binding (Kaca. 105 M-1) to bovine serum albumin (BSA). The interaction through hydrogen bonding and van der Waals forces resulted in a spontaneous process. Site marker competitive experiments showed binding sites for chrysin mainly located in site II (subdomain IIIA) and in site I (subdomain IIIA) for the complex. FT-IR spectral measurements showed evidences of the alterations of protein secondary structure in the presence of chrysin and VIVO(chrys)2.


Assuntos
Antineoplásicos/farmacologia , Movimento Celular/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Flavonoides/farmacologia , Soroalbumina Bovina/metabolismo , Compostos de Vanádio/farmacologia , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Sítios de Ligação , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/metabolismo , Flavonoides/química , Flavonoides/metabolismo , Humanos , Estrutura Molecular , Ligação Proteica , Conformação Proteica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Soroalbumina Bovina/química , Compostos de Vanádio/química , Compostos de Vanádio/metabolismo
14.
Future Med Chem ; 14(1): 9-16, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34730021

RESUMO

Background: The pharmacological response and the therapeutic efficacy of a drug depends on the interactions with plasma proteins. Methodology: The interaction of bovine serum albumin (BSA) with the metal complexes of antihypertensive drugs, Zn(II)/sartan complexes (candesartan, valsartan and losartan), was investigated using fluorescence quenching determinations at different temperatures. Results: The binding studies of the compounds with BSA showed static quenching and moderate binding with calculated constants in the range of 104-106 M-1, indicating potent serum distribution via albumins. In all cases, negative values of free energy are indicative of spontaneous processes and the stabilization of BSA/compound complexes through hydrogen bonding and van der Waals forces. The results for the sartans agree with the reported pharmacokinetics studies. Conclusion: It has been determined that the three sartans and the Zn complexes could be transported and distributed by albumin.


Assuntos
Benzimidazóis/química , Compostos de Bifenilo/química , Complexos de Coordenação/metabolismo , Losartan/química , Soroalbumina Bovina/metabolismo , Tetrazóis/química , Valsartana/química , Zinco/química , Animais , Bovinos , Complexos de Coordenação/química , Cinética , Ligação Proteica , Soroalbumina Bovina/química , Espectrofotometria , Temperatura , Termodinâmica
15.
Food Chem ; 366: 130422, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34392082

RESUMO

Tea cream, produced by interactions among tea ingredients, is undesirable in tea beverage industry. The interaction between bovine serum albumin (BSA) and theaflavin-3,3'-digallate (TFDG, an important component in tea cream and functional substance of black tea) was investigated by fluorescence spectroscopy, ultraviolet-visible (UV-vis) absorption spectroscopy, synchronous fluorescence spectroscopy, fourier-transform infrared (FT-IR) spectroscopy, and molecular docking technique. Multi-spectroscopic experiments demonstrated that TFDG interacted with BSA via static quenching, and the microenvironment around BSA became more hydrophobicity. FT-IR showed that the α-helix of BSA was increased when binding with TFDG. Thermodynamic parameters and molecular docking demonstrated that hydrophobic interactions and hydrogen bonds dominated the interaction between TFDG and BSA. The mechanism proposed in this research could further develop some nanoparticles to excellent biochemical properties while reducing the formation of tea cream, and explore the potential of BSA as transport carrier for TFDG.


Assuntos
Soroalbumina Bovina , Biflavonoides , Sítios de Ligação , Catequina/análogos & derivados , Dicroísmo Circular , Simulação de Acoplamento Molecular , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
16.
Carbohydr Polym ; 275: 118754, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34742448

RESUMO

Herein, environmentally benign chitin nanofiber (ChNF) membranes were fabricated by regulating suspension behavior. The introduction of zeolitic imidazole frameworks (ZIF-8) into the composite membranes led to the domain formation of ChNF derived by coordinative interaction, resulting in pore size-tunable membranes. Based on the rheological, morphological, and structural characterizations, the driving force of pore-size control was studied in the aqueous suspension of ChNF and ZIF-8 according to the relative concentration. At critical concentration, the 30-ChNF membrane presents superior water permeance (40 LMH h-1) while maintaining a high rejection rate (>80% for all organic dyes). Moreover, the molecular size cut-off of the composite membranes for dyes can be controlled in the range of less than 1 nm to 2 nm. The experimental results provide a simple strategy for the preparation of pore tunable ChNF membranes using MOF with high mechanical strength, good durability, high flux, dye rejection, and antifouling ability.


Assuntos
Quitina/química , Imidazóis/química , Estruturas Metalorgânicas/química , Nanofibras/química , Zeolitas/química , Animais , Incrustação Biológica/prevenção & controle , Bovinos , Quitina/farmacologia , Poluentes Ambientais/antagonistas & inibidores , Poluentes Ambientais/metabolismo , Imidazóis/farmacologia , Estruturas Metalorgânicas/farmacologia , Tamanho da Partícula , Soroalbumina Bovina/antagonistas & inibidores , Soroalbumina Bovina/metabolismo , Propriedades de Superfície , Zeolitas/farmacologia
17.
Biochem Biophys Res Commun ; 589: 254-259, 2022 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-34933199

RESUMO

Indocyanine green (ICG) is an FDA-approved near infrared (NIR) imaging agent for diagnosis and imaging guided surgery. It also exhibits phototoxicity under high-dose NIR irradiation, expanding its application as a photo-therapeutic agent. Since ICG's efficiency as a type II photosensitizer has been controversial due to its low triplet state yield, other mechanisms have been explored. While claims of toxic decomposition products, accompanied by irreversible ICG photobleaching, were proposed as the main mechanism, evidences from systemic studies are lacking. In this work, we aimed to unravel the factors affecting ICG photobleaching and the associated photo-killing effect on neuroblastoma, one of the most common pediatric tumors but often escapes therapy. Specifically, we examined how albumin-induced ICG stabilization affects the ICG photobleaching process, and the effect of photobleached ICG on cell proliferation and viability of neuroblastoma cells. It was found that ICG photobleaching was significant only under aerobic conditions and was more efficient in solutions with higher concentration ICG monomers, which were stabilized from aggregates by the presence of BSA while increasing photobleaching and associated oxygen consumption. Photobleached ICG inhibited cell proliferation, indicating another effect of tumor treatment by ICG. Taken together, while enhanced photobleaching by BSA-bound ICG monomers may reduce the photodynamic effect targeting cellular components, the photoproducts directly contribute to tumor growth inhibition and assist in a secondary mechanism to stop tumor growth.


Assuntos
Verde de Indocianina/farmacologia , Neuroblastoma/patologia , Fotodegradação , Animais , Bovinos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Oxigênio/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Soroalbumina Bovina/metabolismo
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120261, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34419830

RESUMO

Bovine serum albumin (BSA) has been used as a transporter protein for levothyroxine (LT4) and rutin, due to its property of binding to various ligands. Rutin binding to the BSA-LT4 complex can bring many benefits due to its proven pharmacological properties. Using Fourier-Transform Infrared Spectroscopy (FT-IR) the changes induced by rutin in the structure of BSA-LT4 complex were determined. Fluorescence studies allowed us to determine the quenching mechanism and affinity of rutin to the BSA-LT4 complex. The thermodynamic parameters suggest the binding of rutin to BSA-LT4 is a spontaneous process, driven by enthalpy and electrostatic forces. Also, the second derivative of the emission spectra suggests the Trp's of BSA are located in two different microenvironments. Thermal and chemical denaturation of BSA-LT4-rutin complex presents similar behavior but with better stability of the complex in case of chemical denaturation. Molecular docking studies show the binding of the two ligands to the same BSA site, suggesting that rutin may influence the bond of LT4 with the protein. Studies on the antioxidant activity of the BSA-LT4-rutin complex suggest that the presence of LT4 decreases the antioxidant activity of the rutin, but even so this antioxidant activity can be used to bring benefits for medical purposes.


Assuntos
Rutina , Soroalbumina Bovina , Sítios de Ligação , Simulação de Acoplamento Molecular , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica , Tiroxina
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120298, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34464920

RESUMO

Dapagliflozin (DAPA) is a selective sodium-glucose cotransporter-2 inhibitor that reduces renal glucose reabsorption. The drug has recently become a crucial milestone in the management of diabetes and heart failure. In this study, the interaction of DAPA with bovine serum albumin (BSA) was investigated for the first time using various fluorescence spectroscopic techniques, UV-absorption spectroscopy, molecular docking, and molecular dynamic (MD) simulation. The fluorescence spectroscopic titration study performed at different temperatures showed that DAPA quenched the fluorescence of BSA through a combination of dynamic and static mechanisms, which was confirmed by UV absorption, fluorescence-resonance energy transfer measurements, and MD simulation. The binding thermodynamic parameters demonstrated that the binding stoichiometry between BSA and DAPA was 1:1. Competitive binding experiments using site-specific markers as well as molecular docking studies showed that DAPA binds to site I on BSA. The positive values of enthalpy change (ΔH) and entropy change (ΔS) revealed that hydrophobic forces played a predominant role in the binding of DAPA to BSA, whereas the negative value of Gibbs free energy change (ΔG) indicated the spontaneity of the interaction. Moreover, the synchronous fluorescence spectroscopy has shown that DAPA binding to the protein molecule occurs in the vicinity of the tryptophan residue. These findings were confirmed by the molecular docking and MD simulation studies.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores do Transportador 2 de Sódio-Glicose , Compostos Benzidrílicos , Sítios de Ligação , Glucosídeos , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Soroalbumina Bovina/metabolismo , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termodinâmica
20.
Biochim Biophys Acta Mol Basis Dis ; 1868(1): 166283, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601015

RESUMO

Advanced glycation end products (AGEs) play a critical pathogenic role in the development of diabetic complications. Recent studies have shown that diabetes is associated with not only abnormal glucose metabolism but also abnormal ribose and fructose metabolism, although glucose is present at the highest concentration in humans. The glycation ability and contribution of ribose and fructose to diabetic complications remain unclear. Here, the glycation ability of ribose, fructose and glucose under a mimic physiological condition, in which the concentration of ribose or fructose was one-fiftieth that of glucose, was compared. Bovine serum albumin (BSA) was used as the working protein in our experiments. Ribose generated more AGEs and was markedly more cytotoxic to SH-SY5Y cells than fructose. The first-order rate constant of ribose glycation was found to be significantly greater than that of fructose glycation. LC-MS/MS analysis revealed 41 ribose-glycated Lys residues and 12 fructose-glycated residues. Except for the shared Lys residues, ribose reacted selectively with 17 Lys, while no selective Lys was found in fructose-glycated BSA. Protein conformational changes suggested that ribose glycation may induce BSA into amyloid-like monomers compared with fructose glycation. The levels of serum ribose were correlated positively with glycated serum protein (GSP) and diabetic duration in type 2 diabetes mellitus (T2DM), respectively. These results indicate that ribose has a greater glycation ability than fructose, while ribose largely contributes to the production of AGEs and provides a new insight to understand in the occurrence and development of diabetes complications.


Assuntos
Complicações do Diabetes/sangue , Diabetes Mellitus Tipo 2/sangue , Produtos Finais de Glicação Avançada/genética , Soroalbumina Bovina/metabolismo , Animais , Bovinos , Cromatografia Líquida , Complicações do Diabetes/metabolismo , Complicações do Diabetes/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Frutose/sangue , Glucose/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Glicosilação , Humanos , Ribose/sangue , Espectrometria de Massas em Tandem
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