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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124950, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39133976

RESUMO

Low fluorescence under visible light excitation and catalytic activity limit many applications of graphene quantum dots in optical detection, biosensing, catalysis and biomedical. The paper reports design and synthesis of histidine, serine and folic acid-functionalized and boron and iron-doped graphene quantum dot (Fe/B-GQD-HSF). The Fe/B-GQD-HSF shows excellent fluorescence behavior and peroxidase-like activity. Excitation of 330 nm ultraviolet light produces the strongest blue fluorescence and excitation of 480 nm visible light produces the strongest yellow fluorescence. The specific activity reaches 92.67 U g-1, which is higher than that of other graphene quantum dots. The Fe/B-GQD-HSF can catalyze oxidation of 3,3',5,5'-tetramethylbenzidine with H2O2 to form blue compound. Based on this, it was used for colorimetric and fluorescence detection of H2O2. The absorbance at 652 nm linearly increases with the increase of H2O2 concentration between 0.5 and 100 µM with detection limit of 0.43 µM. The fluorescence signal linearly decreases with the increase of H2O2 concentration between 0.05 and 100 µM with detection limit of 0.035 µM. The analytical method has been satisfactorily applied in detection of H2O2 in food. The study also paves one way for design and synthesis of functional graphene quantum dots with ideal fluorescence behavior and catalytic activity.


Assuntos
Boro , Colorimetria , Ácido Fólico , Grafite , Histidina , Peróxido de Hidrogênio , Ferro , Pontos Quânticos , Serina , Pontos Quânticos/química , Grafite/química , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Colorimetria/métodos , Ácido Fólico/análise , Ácido Fólico/química , Ferro/análise , Ferro/química , Boro/química , Histidina/análise , Histidina/química , Serina/análise , Serina/química , Espectrometria de Fluorescência/métodos , Limite de Detecção , Análise de Alimentos/métodos , Peroxidase/química , Peroxidase/metabolismo , Catálise
2.
J Environ Sci (China) ; 148: 198-209, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095157

RESUMO

Norfloxacin is widely used owing to its strong bactericidal effect on Gram-negative bacteria. However, the residual norfloxacin in the environment can be biomagnified via food chain and may damage the human liver and delay the bone development of minors. Present work described a reliable and sensitive smartphone colorimetric sensing system based on cobalt-doped Fe3O4 magnetic nanoparticles (Co-Fe3O4 MNPs) for the visual detection of norfloxacin. Compared with Fe3O4, Co-Fe3O4 MNPs earned more remarkably peroxidase-like activity and TMB (colorless) was rapidly oxidized to oxTMB (blue) with the presence of H2O2. Interestingly, the addition of low concentration of norfloxacin can accelerate the color reaction process of TMB, and blue deepening of the solution can be observed with the naked eye. However, after adding high concentration of norfloxacin, the activity of nanozyme was inhibited, resulting in the gradual fading of the solution. Based on this principle, a colorimetric sensor integrated with smartphone RGB mode was established. The visual sensor exhibited good linearity for norfloxacin monitoring in the range of 0.13-2.51 µmol/L and 17.5-100 µmol/L. The limit of visual detection was 0.08 µmol/L. In the actual water sample analysis, the spiked recoveries of norfloxacin were over the range of 95.7%-104.7 %. These results demonstrated that the visual sensor was a convenient and fast method for the efficient and accurate detection of norfloxacin in water, which may have broad application prospect.


Assuntos
Cobalto , Colorimetria , Norfloxacino , Smartphone , Poluentes Químicos da Água , Norfloxacino/análise , Colorimetria/métodos , Cobalto/análise , Cobalto/química , Poluentes Químicos da Água/análise , Antibacterianos/análise , Peroxidase , Limite de Detecção
3.
Sci Rep ; 14(1): 21231, 2024 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-39261545

RESUMO

The study assessed selected parameters of redox status in the plasma of patients suffering from high myopia (HM). Thirty-five children with mean age 13.7 ± 2.7 years with HM and 40 healthy children were included. Plasma redox status parameters were determined using colorimetric kits. The levels of retinol, α-tocopherol and coenzyme Q10 were determined with a high-performance liquid chromatograph. Negative correlations were observed between the concentrations of retinol and the axial length of the eye (r = - 0.514 p < 0.001). Increased myeloperoxidase (MPO) activity (p < 0.018), and decreased concentrations of retinol (p < 0.001) and α-tocopherol (p < 0.023) in patients with HM and the axial length of the eye > 26 mm compared to controls were established. Significantly lower retinol and α-tocopherol concentrations were found in patients with the axial length of the eye > 26 mm compared to those with the axial length of the eye ≤ 26 mm (p < 0.001, p < 0.021, respectively). Increased MPO activity in advanced stages of HM may confirm an inflammatory process in HM patients. Reduced retinol and α-tocopherol concentrations and their link to disease progression indicate a need for monitoring their levels and supplementation in children with HM.


Assuntos
Miopia , Peroxidase , Vitamina A , alfa-Tocoferol , Humanos , alfa-Tocoferol/sangue , Peroxidase/sangue , Vitamina A/sangue , Masculino , Feminino , Criança , Adolescente , Miopia/sangue , Miopia/metabolismo , Estudos de Casos e Controles
4.
Mikrochim Acta ; 191(10): 599, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39276245

RESUMO

A colorimetric sensor for the rapid and sensitive detection of GSH was developed. The hydrothermal method was utilized to synthesize chitosan-stabilized gold nanoparticles (CS-AuNPs). The synthesized CS-AuNPs were characterized by UV-vis absorption spectroscopy, transmission electron microscopy (TEM), X-ray diffractograms (XRD), and Fourier transform infrared spectroscopy (FTIR). The CS-AuNPs are well-dispersed and possess a spherical shape with an average particle size of 10.05 ± 2.26 nm in aqueous solution. They show an intrinsic peroxidase-like activity, which could efficiently catalyze the decomposition of H2O2 to produce •OH radicals. These radicals then oxidized 3, 3´, 5, 5´-tetramethylbenzidine (TMB), resulting in the formation of the blue oxidized product oxTMB, observed a visible color change (from colorless to blue), and oxTMB had an obvious absorption peak at 652 nm. The presence of GSH could inhibit the peroxidase-like activity of CS-AuNPs, thereby reducing the formation of oxTMB. The solution's blue hue underwent a reduction in absorption intensity. Based on this fact, a novel and sensitive colorimetric sensor for detection of GSH was constructed. Under optimal conditions, the results of detection had an excellent linear relationship between the concentration of GSH and ∆A within the range 0.5 ~ 50.0 × 10-6 mol/L. The limit of detection (LOD) for GSH was 2.10 × 10-7 mol/L, which was much lower than those in most previous works. Furthermore, for detection in real human serum samples, the recoveries of GSH and the relative standard deviations (RSD) in the serum were in the range 98.40 ~ 103.32% and 1.85 ~ 3.54%, respectively. Thus, this visual colorimetric method has good precision and can be used for GSH detection in practical applications, promising in the fields of bioanalysis and illness diagnostics.


Assuntos
Quitosana , Colorimetria , Glutationa , Ouro , Limite de Detecção , Nanopartículas Metálicas , Ouro/química , Humanos , Colorimetria/métodos , Quitosana/química , Nanopartículas Metálicas/química , Glutationa/sangue , Glutationa/química , Peróxido de Hidrogênio/química , Benzidinas/química , Peroxidase/química
5.
Int J Mol Sci ; 25(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39273368

RESUMO

This study aimed to compare several potential mouthrinse biomarkers for periodontitis including active matrix-metalloproteinase-8 (aMMP-8), total MMP-8, and other inflammatory biomarkers in diagnosing and monitoring the effects of nonsurgical periodontal therapy. Thirteen patients with stage III/IV periodontitis were recruited, along with thirteen periodontally and systemically healthy controls. These 13 patients were representative of the number of outpatients visiting any dentist in a single day. Full-mouth clinical periodontal parameters and biomarkers (the aMMP-8 point-of-care-test [POCT], total MMP-8, tissue inhibitor of MMPs (TIMP)-1, the aMMP-8 RFU activity assay, Myeloperoxidase, PMN elastase, calprotectin, and interleukin-6) were recorded at baseline and after nonsurgical therapy at 6 weeks. The aMMP-8 POCT was the most efficient and precise discriminator, with a cut-off of 20 ng/mL found to be optimal. Myeloperoxidase, MMP-8's oxidative activator, was also efficient. Following closely in precision was the aMMP-8 RFU activity assay and PMN elastase. In contrast, the total MMP-8 assay and the other biomarkers were less efficient and precise in distinguishing patients with periodontitis from healthy controls. aMMP-8, MPO, and PMN elastase may form a proteolytic and pro-oxidative tissue destruction cascade in periodontitis, potentially representing a therapeutic target. The aMMP-8 chair-side test with a cut-off of 20 ng/mL was the most efficient and precise discriminator between periodontal health and disease. The aMMP-8 POC test can be effectively used by dental professionals in their dental practices in online and real-time diagnoses as well as in monitoring periodontal disease and educating and encouraging good oral practices among patients.


Assuntos
Biomarcadores , Metaloproteinase 8 da Matriz , Periodontite , Humanos , Metaloproteinase 8 da Matriz/metabolismo , Periodontite/diagnóstico , Periodontite/terapia , Periodontite/metabolismo , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Peroxidase/metabolismo , Sistemas Automatizados de Assistência Junto ao Leito , Elastase de Leucócito/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo
6.
Medicine (Baltimore) ; 103(36): e39494, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39252215

RESUMO

Sepsis is an infection-induced systemic inflammatory response syndrome. Immune regulation plays a crucial role in sepsis. We looked into the link between immune effector-related proteins and sepsis in this study by using both univariate and multivariate Mendelian randomization (MR) analyses. We accessed and collected data from the Integrative Epidemiology Unit's Open About Sepsis genome-wide association study database. The 6 immune effector-associated proteins each contained 10,534,735 single-nucleotide polymorphisms from 3301 samples. Using the weighted median, MR-Egger, simplex, inverse-variance weighting, and weighted mode methods, univariate MR then investigated the link between complement factor H-related protein-5 (CFHR5), Fc epsilon receptor II (FCER2), granzyme B (GZMB), major histocompatibility complex, class II, DQ alpha (HLA-DQA2), mannose-binding lectin 2 (MBL2), or myeloperoxidase (MPO) and sepsis. In the inverse-variance weighted results, the P values of all 6 immune effector-related proteins were <0.05, suggesting a possible causal relationship between them and sepsis. MBL2 (odds ratio [OR] = 1.046) was a risk factor for sepsis, while the other proteins (FCER2: OR = 0.922; GZMB: OR = 0.908; CFHR5: OR = 0.858; HLA-DQA2: OR = 0.896; MPO: OR = 0.875) were safety factors. By revealing a causal link between sepsis and CFHR5, FCER2, GZMB, HLA-DQA2, MBL2, or MPO, our study offers an essential resource for additional investigations on the subject.


Assuntos
Estudo de Associação Genômica Ampla , Lectina de Ligação a Manose , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Sepse , Humanos , Sepse/genética , Sepse/imunologia , Lectina de Ligação a Manose/genética , Granzimas/genética , Peroxidase/genética , Peroxidase/imunologia , Fatores de Risco , Predisposição Genética para Doença , Receptores Fc/genética
7.
Anal Chim Acta ; 1326: 343150, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39260918

RESUMO

BACKGROUND: To minimize the impact of pesticide residues in food on human health, it is necessary to enhance their detection. Recently, many nanozyme-based colorimetric methods for pesticides detection have been developed, however, they often required the assistance of natural enzymes, which made the process and result of methods susceptible to the stability and activity of natural enzymes. To overcome these drawbacks, methods for direct detection of pesticides using nanozymes have been developed, and there are few studies in this field currently. Thus, it is of great research and practical significance to develop more nanozymes-based colorimetric methods for direct detection of pesticides. RESULTS: Dual colorimetric platforms based on Os-Rh nanozyme with excellent peroxidase-like activity were constructed for directly detection of glyphosate in this work. Results showed that glyphosate was able to sensitively and selectively inhibit the peroxidase-like activity of Os-Rh nanozyme through hindering the decomposition of H2O2 by Os-Rh nanozyme to produce HO∙. Based on this, the dual colorimetric platforms achieved highly sensitive detection for glyphosate over a wide linear concentration range (50-1000 µg L-1 in solution platform and 200-1000 µg L-1 in paper platform), with the detection limits of 28.37 µg L-1 in solution platform and 400 µg L-1 (naked-eye detection limit)/123.25 µg L-1 (gray scale detection limit) in paper platform, respectively. Moreover, the dual colorimetric platforms possessed satisfactory reliability and accuracy for practical applications, and has been successfully applied to the detection of real samples with the spiked recoveries of 92.78-102.75 % and RSD of 1.17-3.88 %. SIGNIFICANCE: The dual colorimetric platforms for glyphosate direct detection based on Os-Rh nanozyme developed in this work not only owned considerable practical application potential, but also could provide more inspirations and ideas for the rational design and development of colorimetric sensing methods for the rapid detection of pesticides based on nanozymes.


Assuntos
Colorimetria , Glicina , Glifosato , Colorimetria/métodos , Glicina/análogos & derivados , Glicina/análise , Glicina/química , Peroxidase/metabolismo , Peroxidase/química , Limite de Detecção , Peróxido de Hidrogênio/química
8.
Mediators Inflamm ; 2024: 8847492, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39238946

RESUMO

The pathogenesis of acute lung injury is complex. Studies have demonstrated the role of neutrophil extracellular traps (NETs) in the process of lipopolysaccharide (LPS)-induced acute lung injury (ALI). However, the underlying mechanism remains unclear. In this study, the regulation of Nrf2 in the formation of NETs, which was pathogenic in LPS-induced ALI, was identified by analyzing the levels of Cit-H3, lung function, lung tissue pathology, lung wet/dry ratio, the inflammatory cells, cytokines and proteins in the bronchoalveolar lavage fluid (BALF) and in addition, the activity of lung myeloperoxidase (MPO) was also measured. Results showed that the levels of Cit-H3 measured by western blot in Nrf2-knockout (KO) mice were higher compared with the WT mice after LPS stimulation. To further investigate the NETs formation was pathogenic during LPS-induced ALI, the Nrf2-KO mice were treated with DNase I. Results showed that DNase I improved lung function and lung tissue pathology and significantly reduced lung wet/dry ratio and proteins in the BALF. Besides, DNase I also attenuated the infiltration of inflammatory cells and the cytokines (TNF-α, IL-1ß) production in the BALF and the activity of lung MPO. Therefore, these results together indicate that Nrf2 may intervene in the release of NETs during LPS-induced ALI in mice.


Assuntos
Lesão Pulmonar Aguda , Líquido da Lavagem Broncoalveolar , Armadilhas Extracelulares , Lipopolissacarídeos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2 , Animais , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Fator 2 Relacionado a NF-E2/metabolismo , Camundongos , Armadilhas Extracelulares/metabolismo , Líquido da Lavagem Broncoalveolar/química , Masculino , Peroxidase/metabolismo , Neutrófilos/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Interleucina-1beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Desoxirribonuclease I/metabolismo , Citocinas/metabolismo , Western Blotting
9.
Acta Cir Bras ; 39: e395524, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39230095

RESUMO

PURPOSE: To investigate the impact of the Chinese medicine compound Ento-PB on oxazolone (OXZ)-induced ulcerative colitis (UC) in rats. METHODS: UC rats induced by OXZ were treated with Ento-PB. The damage to the colon was assessed using several measures, including the disease activity index (DAI), colon length, colon weight/length ratio, colonic mucosal damage index, and histological score. The levels of interleukin-4 (IL-4), interleukin-10 (IL-10), interleukin-13 (IL-13), epidermal growth factor (EGF), inducible nitric oxide synthase, and total nitric oxide synthase (tNOS) in rat serum, as well as the levels of tumor necrosis factor-α (TNF-α) and myeloperoxidase (MPO) in rat colon tissue, were determined using enzyme-linked immunosorbent assay and conventional kits. RESULTS: After being treated with Ento-PB, the DAI score and macroscopic lesion score of OXZ-induced UC rats were significantly reduced. Ento-PB prevented the shortening of rat colons, reduced the ratio of colon weight to length, and improved colon tissue lesions. Meanwhile, Ento-PB could significantly inhibit the activities of proinflammatory cytokines TNF-α, IL-13, and MPO, as well as tNOS and iNOS, while upregulating the expression of anti-inflammatory cytokines IL-4 and IL-10. Moreover, a significant increase in the expression level of EGF was observed in UC rats treated with Ento-PB, indicating that Ento-PB could enhance the repair of damaged intestinal epithelial tissue. CONCLUSIONS: Ento-PB demonstrates significant anti-UC activities in OXZ-induced UC rats by regulating the expression levels of inflammatory factors and promoting the repair of colon tissue. This study provides scientific evidence to support the further development of Ento-PB.


Assuntos
Colite Ulcerativa , Colo , Oxazolona , Peroxidase , Animais , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/patologia , Masculino , Colo/efeitos dos fármacos , Colo/patologia , Colo/metabolismo , Peroxidase/análise , Peroxidase/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Modelos Animais de Doenças , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/metabolismo , Ratos Sprague-Dawley , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Ratos , Ensaio de Imunoadsorção Enzimática , Fator de Crescimento Epidérmico/análise , Citocinas/metabolismo , Interleucina-13/análise , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/análise , Reprodutibilidade dos Testes , Resultado do Tratamento
10.
Plant Signal Behav ; 19(1): 2400451, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-39235999

RESUMO

Lead is one of the major environmental pollutants which is highly toxic to plants and living beings. The current investigation thoroughly evaluated the synergistic effects of oxalic acid (OA) and salicylic acid (SA) on Zea mays L. plants subjected to varying durations (15, 30, 30, and 45 days) of lead (Pb) stress. Besides, the effects of oxalic acid (OA) combined with salicylic acid (SA) for different amino acids at various periods of Pb stress were also investigated on Zea mays L. The soil was treated with lead nitrate Pb (NO3)2 (0.5 mM) to induce Pb stress while the stressed plants were further treated using oxalic acid (25 mg/L), salicylic acid (25 mg/L), and their combination OA + SA (25 mg/L each). Measurements of protein content, malondialdehyde (MDA) levels, guaiacol peroxidase (GPOX) activity, catalase (CAT) activity, GSH content, and Pb concentration in maize leaves were done during this study. MDA levels increased by 71% under Pb stress, while protein content decreased by 56%, GSH content by 35%, and CAT activity by 46%. After treatment with SA, OA, and OA+SA, there was a significant reversal of these damages, with the OA+SA combination showing the highest improvement. Specifically, OA+SA treatment led to a 45% increase in protein content and a 39% reduction in MDA levels compared to Pb treatment alone. Moreover, amino acid concentrations increased by 68% under the Pb+OA+SA treatment, reflecting the most significant recovery (p < 0.0001).


Assuntos
Aminoácidos , Chumbo , Malondialdeído , Ácido Oxálico , Ácido Salicílico , Estresse Fisiológico , Zea mays , Zea mays/efeitos dos fármacos , Zea mays/metabolismo , Chumbo/toxicidade , Ácido Oxálico/metabolismo , Ácido Oxálico/farmacologia , Ácido Salicílico/farmacologia , Aminoácidos/metabolismo , Malondialdeído/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Catalase/metabolismo , Peroxidase/metabolismo , Glutationa/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Sinergismo Farmacológico , Proteínas de Plantas/metabolismo
11.
Mikrochim Acta ; 191(10): 588, 2024 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256210

RESUMO

Different morphological Cu2O nanoparticles including cube, truncated cube, and octahedron were successfully prepared by a selective surface stabilization strategy. The prepared cube Cu2O exhibited superior peroxidase-like activity over the other two morphological Cu2O nanoparticles, which can readily oxidize 3,3',5,5'-tetramethylbenzidine (TMB) to form visually recognizable color signals. Consequently, a sensitive and simple colorimetric biosensor was proposed for deoxynivalenol (DON) detection. In this biosensor, the uniform cube Cu2O was employed as the vehicle to label the antibody for the recognition of immunoreaction. The sensing strategy showed a detection limit as low as 0.01 ng/mL, and a wide linear range from 2 to 100 ng/mL. Concurrently, the approximate DON concentration can be immediately and conveniently observed by the vivid color changes. Benefiting from the high sensitivity and selectivity of the designed biosensor, the detection of DON in wheat, corn, and tap water samples was achieved, suggesting the bright prospect of the biosensor for the convenient and intuitive detection of DON in actual samples.


Assuntos
Benzidinas , Técnicas Biossensoriais , Colorimetria , Cobre , Limite de Detecção , Nanopartículas Metálicas , Tricotecenos , Zea mays , Tricotecenos/análise , Tricotecenos/imunologia , Colorimetria/métodos , Cobre/química , Técnicas Biossensoriais/métodos , Benzidinas/química , Zea mays/química , Nanopartículas Metálicas/química , Triticum/química , Peroxidase/química , Anticorpos Imobilizados/imunologia , Contaminação de Alimentos/análise
12.
Colloids Surf B Biointerfaces ; 244: 114137, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39116601

RESUMO

BACKGROUND: Overcoming radio-resistance and enhance radio-sensitivity to obtain desired therapeutic outcome plays an important role in treating cancer. METHODS: Here we constructed a versatile enzyme-like nano-radiosensitizer MDP. MDP is composed of MnCO decorated and Ru-based nanozyme with triphenylphosphine (TPP) group coordinated on the surface. RESULTS: Due to the mitochondria-targeting ability of TPP and enhanced permeability and retention effect (EPR) effect of MDP, MDP accumulated in the mitochondria of tumor cells. Therefore, quantities of reactive oxygen species were produced via multiple enzyme-like properties including peroxidase (POD) and catalase (CAT) in a tumor microenvironment mimicking status. In additional, more energy of radiation ionizing was deposed in tumor site via Compton effect and secondary electron scattering by Ru element. Impressively, it was disclosed that the nanozyme can act as a cGAS-STING agonist to provoke immune response of the system, which hereby further elevated this combined therapy. CONCLUSIONS: Collectively, we fabricated a novel nanozyme with POD and CAT mimicking properties for the combination therapy of catalytical therapy, radiotherapy as well as immune therapy to eliminate cancer.


Assuntos
Mitocôndrias , Humanos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Animais , Nucleotidiltransferases/metabolismo , Nucleotidiltransferases/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Compostos Organofosforados/química , Compostos Organofosforados/farmacologia , Radiossensibilizantes/química , Radiossensibilizantes/farmacologia , Catalase/metabolismo , Linhagem Celular Tumoral , Catálise , Nanopartículas/química , Rutênio/química , Rutênio/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/terapia , Propriedades de Superfície , Tamanho da Partícula , Peroxidase/metabolismo
13.
JCI Insight ; 9(14)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-39133648

RESUMO

Neutrophils (polymorphonuclear leukocytes, PMNs) comprise a major component of the immune cell infiltrate during acute mucosal inflammation and have an important role in molding the inflammatory tissue environment. While PMNs are essential to clearance of invading microbes, the major PMN antimicrobial enzyme myeloperoxidase (MPO) can also promote bystander tissue damage. We hypothesized that blocking MPO would attenuate acute colitis and prevent the development of chronic colitis by limiting bystander tissue damage. Using the acute and chronic dextran sodium sulfate model of murine colitis, we demonstrated that MPO-deficient mice experienced less inflammation and more rapidly resolved colitis relative to wild-type controls. Mechanistic studies demonstrated that activated MPO disrupted intestinal epithelial barrier function through the dysregulation of the epithelial tight junction proteins. Our findings revealed that activated MPO chlorinates tyrosine within several tight junction proteins, thereby promoting tight junction mislocalization and dysfunction. These observations in cell models and in murine colitis were validated in human intestinal biopsies from individuals with ulcerative colitis and revealed a strong correlation between disease severity (Mayo score) and tissue chlorinated tyrosine levels. In summary, these findings implicate MPO as a viable therapeutic target to limit bystander tissue damage and preserve mucosal barrier function during inflammation.


Assuntos
Modelos Animais de Doenças , Mucosa Intestinal , Neutrófilos , Peroxidase , Proteínas de Junções Íntimas , Peroxidase/metabolismo , Animais , Camundongos , Humanos , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Neutrófilos/metabolismo , Neutrófilos/imunologia , Proteínas de Junções Íntimas/metabolismo , Colite/patologia , Colite/metabolismo , Colite/induzido quimicamente , Halogenação , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos Knockout , Sulfato de Dextrana/toxicidade , Junções Íntimas/metabolismo , Feminino , Camundongos Endogâmicos C57BL , Colite Ulcerativa/patologia , Colite Ulcerativa/metabolismo
14.
Bull Exp Biol Med ; 177(2): 197-202, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39090470

RESUMO

Type 2 diabetes mellitus (T2DM) is accompanied by halogenative stress resulting from the excessive activation of neutrophils and neutrophilic myeloperoxidase (MPO) generating highly reactive hypochlorous acid (HOCl). HOCl in blood plasma modifies serum albumin (Cl-HSA). We studied the formation of neutrophil extracellular traps (NETs) in the whole blood and by isolated neutrophils under the action of Cl-HSA. It was found that Cl-HSA induces neutrophil priming and NETosis. MPO-containing as well as MPO-free NETs were found. These NETs with different composition can be a product of NETosis of one and the same neutrophil. NET formation in neutrophils with vacuolated cytoplasm was detected. In the presence of Cl-HSA, acceleration of NET degradation was observed. Accelerated NET degradation and neutrophil priming can be the factors contributing to the development of complications in T2DM.


Assuntos
Armadilhas Extracelulares , Ácido Hipocloroso , Neutrófilos , Peroxidase , Ácido Hipocloroso/metabolismo , Ácido Hipocloroso/farmacologia , Neutrófilos/metabolismo , Neutrófilos/efeitos dos fármacos , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/efeitos dos fármacos , Humanos , Peroxidase/metabolismo , Diabetes Mellitus Tipo 2/sangue , Albumina Sérica/metabolismo , Masculino
15.
Sci Rep ; 14(1): 17944, 2024 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095388

RESUMO

This study demonstrates that root-associated Kosakonia oryziphila NP19, isolated from rice roots, is a promising plant growth-promoting bioagent and biopesticide for combating rice blast caused by Pyricularia oryzae. In vitro experiments were conducted on fresh leaves of Khao Dawk Mali 105 (KDML105) jasmine rice seedlings. The results showed that NP19 effectively inhibited the germination of P. oryzae fungal conidia. Fungal infection was suppressed across three different treatment conditions: rice colonized with NP19 and inoculated by fungal conidia, a mix of NP19 and fungal conidia concurrently inoculated on the leaves, and fungal conidia inoculation first followed by NP19 inoculation after 30 h. Additionally, NP19 reduced fungal mycelial growth by 9.9-53.4%. In pot experiments, NP19 enhanced the activities of peroxidase (POD) and superoxide dismutase (SOD) by 6.1-63.0% and 3.0-67.7%, respectively, indicating a boost in the plant's defense mechanisms. Compared to the uncolonized control, the NP19-colonized rice had 0.3-24.7% more pigment contents, 4.1% more filled grains per panicle, 26.3% greater filled grain yield, 34.4% higher harvest index, and 10.1% more content of the aroma compound 2-acetyl-1-pyrroline (2AP); for rice colonized with NP19 and infected with P. oryzae, these increases were 0.2-49.2%, 4.6%, 9.1%, 54.4%, and 7.5%, respectively. In field experiments, blast-infected rice that was colonized and/or inoculated with NP19 treatments had 15.1-27.2% more filled grains per panicle, 103.6-119.8% greater filled grain yield, and 18.0-35.8% higher 2AP content. A higher SOD activity (6.9-29.5%) was also observed in the above-mentioned rice than in the blast-infected rice that was not colonized and inoculated with NP19. Following blast infection, NP19 applied to leaves decreased blast lesion progression. Therefore, K. oryziphila NP19 was demonstrated to be a potential candidate for use as a plant growth-promoting bioagent and biopesticide for suppressing rice blast.


Assuntos
Oryza , Doenças das Plantas , Oryza/microbiologia , Oryza/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Raízes de Plantas/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Esporos Fúngicos , Folhas de Planta/microbiologia , Ascomicetos/patogenicidade , Plântula/microbiologia , Plântula/crescimento & desenvolvimento , Agentes de Controle Biológico/farmacologia , Peroxidase/metabolismo
16.
Langmuir ; 40(32): 16909-16920, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39087886

RESUMO

We have prepared a novel assembly with copper nanoclusters (CuNCs) and imidazolium-based gemini surfactants (different chain lengths). These novel mimic enzymes formed through the assembly of nanocluster-gemini surfactants have been utilized in creating colorimetric sensors to detect biomolecules. Yet, understanding the method for detecting glutathione (GSH) and its sensing mechanism using this specific assembly-based colorimetric sensor poses a significant challenge. Because of the role of surface ligands, the complexes of cysteine-capped CuNCs (Cys-CuNCs) and gemini surfactants exhibit strong amphiphilicity, enabling them to self-assemble like a molecular amphiphile. We have investigated the kinetics and catalytic capabilities of this Cys-CuNCs@gemini surfactant assembly through peroxidase-like activity. Additionally, a sensitive and simple-to-use colorimetric sensing approach for glutathione (GSH) is also disclosed here, demonstrating a low limit of detection, by using this peroxidase-like activity of Cys-CuNCs@gemini surfactant assemblies. Thus, the remarkable advantages of the Cys-CuNCs@gemini surfactant nanozyme make it suitable for the precise colorimetric detection of GSH, demonstrating excellent sensitivity and reliable selectivity. Additionally, it performs well in detecting GSH in various soft drinks.


Assuntos
Colorimetria , Cobre , Cisteína , Glutationa , Nanopartículas Metálicas , Tensoativos , Cobre/química , Glutationa/análise , Glutationa/química , Colorimetria/métodos , Tensoativos/química , Cisteína/análise , Cisteína/química , Nanopartículas Metálicas/química , Imidazóis/química , Peroxidase/química , Peroxidase/metabolismo
17.
Int J Mol Sci ; 25(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39125806

RESUMO

Cytochrome c (CytC), a one-electron carrier, transfers electrons from complex bc1 to cytochrome c oxidase (CcO) in the electron-transport chain. Electrostatic interaction with the partners, complex bc1 and CcO, is ensured by a lysine cluster near the heme forming the Universal Binding Site (UBS). We constructed three mutant variants of mitochondrial CytC with one (2Mut), four (5Mut), and five (8Mut) Lys->Glu substitutions in the UBS and some compensating Glu->Lys substitutions at the periphery of the UBS for charge compensation. All mutants showed a 4-6 times increased peroxidase activity and accelerated binding of cyanide to the ferric heme of CytC. In contrast, decomposition of the cyanide complex with ferrous CytC, as monitored by magnetic circular dichroism spectroscopy, was slower in mutants compared to WT. Molecular dynamic simulations revealed the increase in the fluctuations of Cα atoms of individual residues of mutant CytC compared to WT, especially in the Ω-loop (70-85), which can cause destabilization of the Fe…S(Met80) coordination link, facilitation of the binding of exogenous ligands cyanide and peroxide, and an increase in peroxidase activity. It was found that only one substitution K72E is enough to induce all these changes, indicating the significance of K72 and the Ω-loop (70-85) for the structure and physiology of mitochondrial CytC. In this work, we also propose using a ferro-ferricyanide buffer as a substrate to monitor the peroxidase activity of CytC. This new approach allows us to determine the rate of peroxidase activity at moderate (200 µM) concentrations of H2O2 and avoid complications of radical formation during the reaction.


Assuntos
Citocromos c , Simulação de Dinâmica Molecular , Sítios de Ligação , Ligantes , Citocromos c/metabolismo , Citocromos c/química , Citocromos c/genética , Peroxidase/metabolismo , Peroxidase/química , Peroxidase/genética , Substituição de Aminoácidos , Ligação Proteica , Cianetos/metabolismo , Cianetos/química , Animais , Heme/metabolismo , Heme/química , Mutação
18.
World J Microbiol Biotechnol ; 40(10): 303, 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153119

RESUMO

Dye-decolorizing peroxidases (DyPs) belong to a novel superfamily of heme peroxidases that can oxidize recalcitrant compounds. In the current study, the GlDyP2 gene from Ganoderma lucidum was heterologously expressed in Escherichia coli, and the enzymatic properties of the recombinant GlDyP2 protein were investigated. The GlDyP2 protein could oxidize not only the typical peroxidase substrate ABTS but also two lignin substrates, namely guaiacol and 2,6-dimethoxy phenol (DMP). For the ABTS substrate, the optimum pH and temperature of GlDyP2 were 4.0 and 35 °C, respectively. The pH stability and thermal stability of GlDyP2 were also measured; the results showed that GlDyP2 could function normally in the acidic environment, with a T50 value of 51 °C. Moreover, compared to untreated controls, the activity of GlDyP2 was inhibited by 1.60 mM of Mg2+, Ni2+, Mn2+, and ethanol; 0.16 mM of Cu2+, Zn2+, methanol, isopropyl alcohol, and Na2EDTA·2H2O; and 0.016 mM of Fe2+ and SDS. The kinetic constants of recombinant GlDyP2 for oxidizing ABTS, Reactive Blue 19, guaiacol, and DMP were determined; the results showed that the recombination GlDyP2 exhibited the strongest affinity and the most remarkable catalytic efficiency towards guaiacol in the selected substrates. GlDyP2 also exhibited decolorization and detoxification capabilities towards several dyes, including Reactive Blue 19, Reactive Brilliant Blue X-BR, Reactive Black 5, Methyl Orange, Trypan Blue, and Malachite Green. In conclusion, GlDyP2 has good application potential for treating dye wastewater.


Assuntos
Corantes , Estabilidade Enzimática , Escherichia coli , Guaiacol , Proteínas Recombinantes , Reishi , Temperatura , Corantes/metabolismo , Corantes/química , Reishi/genética , Reishi/enzimologia , Reishi/metabolismo , Concentração de Íons de Hidrogênio , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Guaiacol/metabolismo , Guaiacol/análogos & derivados , Biodegradação Ambiental , Cinética , Benzotiazóis/metabolismo , Especificidade por Substrato , Lignina/metabolismo , Oxirredução , Peroxidase/genética , Peroxidase/metabolismo , Peroxidase/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/química , Peroxidases/genética , Peroxidases/metabolismo , Peroxidases/química , Poluentes Químicos da Água/metabolismo , Compostos Azo/metabolismo , Águas Residuárias/microbiologia , Águas Residuárias/química , Ácidos Sulfônicos/metabolismo , Antraquinonas , Corantes de Rosanilina
19.
Nat Commun ; 15(1): 6888, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39134525

RESUMO

Constructing atom-pair engineering and improving the activity of metal single-atom nanozyme (SAzyme) is significant but challenging. Herein, we design the atom-pair engineering of Zn-SA/CNCl SAzyme by simultaneously constructing Zn-N4 sites as catalytic sites and Zn-N4Cl1 sites as catalytic regulator. The Zn-N4Cl1 catalytic regulators effectively boost the peroxidase-like activities of Zn-N4 catalytic sites, resulting in a 346-fold, 1496-fold, and 133-fold increase in the maximal reaction velocity, the catalytic constant and the catalytic efficiency, compared to Zn-SA/CN SAzyme without the Zn-N4Cl1 catalytic regulator. The Zn-SA/CNCl SAzyme with excellent peroxidase-like activity effectively inhibits tumor cell growth in vitro and in vivo. The density functional theory (DFT) calculations reveal that the Zn-N4Cl1 catalytic regulators facilitate the adsorption of *H2O2 and re-exposure of Zn-N4 catalytic sites, and thus improve the reaction rate. This work provides a rational and effective strategy for improving the peroxidase-like activity of metal SAzyme by atom-pair engineering.


Assuntos
Peroxidase , Zinco , Humanos , Catálise , Peroxidase/metabolismo , Peroxidase/química , Zinco/química , Zinco/metabolismo , Animais , Domínio Catalítico , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Camundongos , Linhagem Celular Tumoral , Teoria da Densidade Funcional
20.
J Vis Exp ; (209)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39141533

RESUMO

Wheat plants infested by Russian wheat aphids (RWA) induce a cascade of defense responses, including the hypersensitive responses (HR) and induction of pathogenesis-related (PR) proteins, such as ß-1,3-glucanase and peroxidase (POD). This study aims to characterize the physicochemical properties of cell wall-associated POD and ß-1,3-glucanase and determine their synergism on the cell wall modification during RWASA2-wheat interaction. The susceptible Tugela, moderately resistant Tugela-Dn1, and resistant Tugela-Dn5 cultivars were pregerminated and planted under greenhouse conditions, fertilized 14 days after planting, and irrigated every 3 days. The plants were infested with 20 parthenogenetic individuals of the same RWASA2 clone at the 3-leaf stage, and leaves were harvested at 1 to 14 days post-infestation. The Intercellular wash fluid (IWF) was extracted using vacuum filtration and stored at -20 °C. Leaf residues were crushed into powder and used for cell wall components. POD activity and characterization were determined using 5 mM guaiacol substrate and H2O2, monitoring change in absorbance at 470 nm. ß-1,3-glucanase activity, pH, and temperature optimum conditions were demonstrated by measuring the total reducing sugars in the hydrolysate with DNS reagent using ß-1,3-glucan and ß-1,3-1,4-glucan substrates, measuring the absorbance at 540 nm, and using glucose standard curve. The pH optimum was determined between pH 4 to 9, temperature optimum between 25 and 50 °C, and thermal stability between 30 °C and 70 °C. ß-1,3-glucanase substrate specificity was determined at 25 °C and 40 °C using curdlan and barley ß-1,3-1,4-glucan substrates. Additionally, the ß-1,3-glucanase mode of action was determined using laminaribiose to laminaripentaose. The oligosaccharide hydrolysis product patterns were qualitatively analyzed with thin-layer chromatography (TLC) and quantitatively analyzed with HPLC. The method presented in this study demonstrates a robust approach for infesting wheat with RWA, extracting peroxidase and ß-1,3-glucanase from the cell wall region and their comprehensive biochemical characterization.


Assuntos
Afídeos , Parede Celular , Triticum , Triticum/química , Parede Celular/química , Parede Celular/metabolismo , Animais , Glucana 1,3-beta-Glucosidase/metabolismo , Glucana 1,3-beta-Glucosidase/química , Peroxidase/química , Peroxidase/metabolismo , Doenças das Plantas/parasitologia
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