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 , CatáliseRESUMO
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 HOâ. 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/químicaRESUMO
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 BlottingRESUMO
BACKGROUND: Validated biomarkers could catalyze environmental enteric dysfunction (EED) research. OBJECTIVES: Leveraging an EED histology scoring system, this multicountry analysis examined biomarker associations with duodenal histology features among children with EED. We also examined differences in 2-h compared with 1-h urine collections in the lactulose rhamnose (LR) dual sugar test. METHODS: Three cohorts of undernourished children unresponsive to nutrition intervention underwent esophagogastroduodenoscopy and duodenal biopsies. Histopathology scores were compared to fecal calprotectin (CAL), myeloperoxidase (MPO), neopterin (NEO), and urinary LR ratio and lactulose percentage recovery. Log-transformed biomarkers were used in linear regressions adjusted for age, center, and sample collection-biopsy time interval in multivariable models. RESULTS: Data on >1 biomarker were available for 120 Bangladeshi (CAL, MPO, NEO, and LR), 63 Pakistani (MPO, NEO, and LR), and 63 Zambian children (CAL). Median age at endoscopy was similar (19 mo) across centers. Median sample collection prior to endoscopy was consistent with each center's study design: 2 wk in Bangladesh (urine and stool) and Zambia (stool), and 6 (urine) and 11 (stool) mo in Pakistan. In multivariable models, intraepithelial lymphocytes were associated with CAL (exponentiated [exp.] coefficient: 1.19; 95% confidence interval [CI]: 1, 1.41), intramucosal Brunner's glands with MPO (exp. coefficient: 1.33; 95% CI: 1.05, 1.69) and NEO (exp. coefficient: 1.37; 95% CI: 1.1, 1.7), and chronic inflammation with NEO (exp. coefficient: 1.61; 95% CI: 1.17, 2.17). Intraepithelial lymphocytes were associated with lactulose % recovery (exp. coefficient: 1.22; 95% CI: 1.05, 1.41). LR recovery was substantially lower in 1-h collections than in 2-h collections. CONCLUSIONS: Four commonly used markers of enteric dysfunction were associated with specific histologic features. One-hour urine collection may be insufficient to reflect small bowel permeability in LR testing. While acknowledging the challenges with obtaining relevant tissue, these findings form the basis for further EED biomarker validation research.
Assuntos
Biomarcadores , Humanos , Biomarcadores/urina , Feminino , Masculino , Lactente , Estudos de Coortes , Pré-Escolar , Fezes/química , Intestino Delgado/patologia , Lactulose/urina , Transtornos da Nutrição Infantil/patologia , Bangladesh , Complexo Antígeno L1 Leucocitário/análise , Zâmbia , Neopterina/urina , Peroxidase/metabolismo , DesnutriçãoRESUMO
<b>Background and Objective:</b> Peroxidase (POD) is the most widely used enzyme in the manufacture of diagnostic kits, biosensors, immunohistochemistry and different industrial sectors. In this study, the POD was extracted from some local vegetables in Thailand; water mimosa. The POD was biochemically purified and characterized from water mimosa. <b>Materials and Methods:</b> The comparison of the peroxidase enzyme activity from water mimosa using Ion exchange chromatography was analyzed statistically using the Kruskal-Wallis one-way ANOVA non-parametric test. Crude extracted from water mimosa was purified by ion exchange chromatography by two techniques (DEAE-Sepharose chromatographic step and CM-Sepharose chromatographic). <b>Results:</b> The crude enzyme from water mimosa exhibited the highest peroxidase activity at 1,7458.5 U/mL. After purification, the peroxidase enzyme in the DEAE-Sepharose column showed a 1.61-fold increase in purity at a NaCl concentration of 0.0 M in 20 mM Tris-HCl buffer, pH 7.2, with a remaining yield of 46.15%. However, after DEAE-Sepharose and CM-Sepharose columns, the purity increased by 1.64-fold at a NaCl concentration of 0.0 M in 20 mM sodium acetate, pH 5.5, but the remaining yield was only 7.45%. The molecular weight of the POD enzyme was 32.3+2 kDa (n = 5) by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE). The enzyme activity of POD showed approximately 3,500 U/mL at pH 6.8 and the optimum temperature was 37°C. From these studies, peroxidase activities in water mimosa demonstrated a "high total activity". <b>Conclusion:</b> These results suggested that POD from water mimosa could replace horseradish peroxidase (HRP), the most used peroxidase, which is very valuable to reduce the costs of biosensors or diagnostic kit applications.
Assuntos
Peroxidase , Cromatografia por Troca Iônica , Peroxidase/metabolismo , Peroxidase/química , Peroxidase/isolamento & purificação , Concentração de Íons de Hidrogênio , Peroxidases/isolamento & purificação , Peroxidases/metabolismoRESUMO
Di(2-ethylhexyl)phthalate (DEHP) is one of the most widely used plasticizers in plastic manufacturing. However, the toxicological effects of DEHP on dandelions remain poorly understood. This study comprehensively analyzed and explored the response mechanisms of dandelions to 1, 10, 50, and 100 mg L-1 DEHP influencing the morphophysiological growth, metabolomics, and molecular docking. DEHP reduced chlorophyll synthesis, inhibited plant growth, and induced oxidative-state-associated stress, which was manifested by the excessive production of reactive oxygen species, an increase in antioxidant enzyme activities, and enhanced synthesis of some osmoregulatory compounds, including proline and soluble protein. An analysis of the integrated biological response index showed that the toxicity was dose-dependent. Molecular docking demonstrated that DEHP could bind stably to three enzymes, and the binding energy was peroxidase (POD) > catalase (CAT) > superoxide dismutase (SOD). Metabolomics revealed that metabolite abundance and metabolic pathways were altered by DEHP, with 88 and 72 primary metabolites identified in shoots and roots, respectively. Amino acid, sugar, and organic acid metabolism were severely disturbed, with the most significant effects being on carbohydrate metabolism, valine, leucine, and isoleucine biosynthesis. Our study elucidated the influence of DEHP exposure on dandelions, providing new insights into the toxicity mechanisms and toxicological risk assessment.
Assuntos
Dietilexilftalato , Simulação de Acoplamento Molecular , Plastificantes , Taraxacum , Dietilexilftalato/toxicidade , Plastificantes/toxicidade , Taraxacum/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Catalase/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Clorofila/metabolismo , Metabolômica , Peroxidase/metabolismoRESUMO
Recently, MOFs@AuNPs composites-based catalysts via anchoring of AuNPs onto metal-organic-frameworks (MOFs) have attracted great attention. However, the influence of the AuNPs loading amounts on the catalytic activity of MOFs@AuNPs composites remains largely unexplored. Here, ficin (Fic) protected AuNPs (Fic@AuNPs) anchored onto the surface of UiO-66-NH2 (UiO) modified with poly(2-vinyl-4,4-dimethyl-2-oxazolidine) (PV) were designed and constructed. The UiOPVFic@AuNPs composites with longer PV chains leading to high-loading Fic@AuNPs exhibited intense peroxidase (POD)-mimetic activity in 3,3'5,5'-tetramethylbenzidine (TMB) oxidation. Further, following the colour-fading, dopamine (DA) was sensitively and selectively monitored in the composites-TMB-H2O2 system. The portable smartphone sensing platform-based colourimetric method had good linearity ranging from 3.34 to 36.7 µM (R2 = 0.995), with a limit of detection of 0.3 µM. This protocol explores high-loading AuNPs on polymer-MOFs composites, providing deep insights into understanding catalytic activity improvements of polymer-MOFs@AuNPs catalysts and revealing their application potential in real biological samples analysis.
Assuntos
Benzidinas , Colorimetria , Dopamina , Ouro , Peróxido de Hidrogênio , Nanopartículas Metálicas , Estruturas Metalorgânicas , Humanos , Benzidinas/química , Materiais Biomiméticos/química , Catálise , Colorimetria/métodos , Dopamina/química , Dopamina/análise , Ficina/química , Ouro/química , Peróxido de Hidrogênio/química , Limite de Detecção , Nanopartículas Metálicas/química , Estruturas Metalorgânicas/química , Oxirredução , Peroxidase/química , Peroxidase/metabolismo , Polivinil/química , SmartphoneRESUMO
In the present research, Fe-based metal-organic frameworks (MIL-101(Fe)-NH2) nanoparticles were synthesized by simple solvothermal methods and used to assay Cr(â ¥). The MIL-101(Fe)-NH2 performs dual functions: the 2-aminoterephthalic acid (NH2-BDC) ligand endows a strong fluorescence emission, and the Fe metal nodes are able to facilitate the oxidation of 3,3',5,5'- tetramethylbenzidine (TMB) directly, resulting in the generation of oxidized-TMB (ox-TMB). Our research results showed that reducing agents such as ascorbic acid (AA) can collapse the structures of MIL-101(Fe)-NH2 because of the reduction of Fe3+ by AA, resulting in release of NH2-BDC. In the presence of Cr(â ¥), the fluorescence intensity of the MIL-101(Fe)-NH2 + AA system will be decreased due to the competitive reduction of Fe3+ and Cr(â ¥). Nevertheless, Cr(â ¥) can significantly accelerate the oxidation of TMB by MIL-101(Fe)-NH2 as it boosts the electron transfer rate between Fe3+ and Fe2+. Therefore, a fluorescent/colorimetric dual-mode platform was developed for the detection of Cr(â ¥) with an extensive linear range (7.5-750 µg/L and 13.3-1000 µg/L) as well as a remarkably low detection limit (0.99 µg/L and 1.98 µg/L). This MOF with the ability to release ligands not only provides inspiration for the design of new luminescent materials, but also offers a novel and reliable solution for the detection of Cr(â ¥).
Assuntos
Cromo , Colorimetria , Corantes Fluorescentes , Estruturas Metalorgânicas , Cromo/análise , Cromo/química , Estruturas Metalorgânicas/química , Corantes Fluorescentes/química , Colorimetria/métodos , Limite de Detecção , Benzidinas/química , Oxirredução , Ferro/química , Espectrometria de Fluorescência/métodos , Peroxidase/química , Peroxidase/metabolismo , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/químicaRESUMO
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/metabolismoRESUMO
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 TratamentoRESUMO
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/metabolismoRESUMO
Trichoderma longibrachiatum UN32 is a well-documented mutant strain known to produce dendrobine-type total alkaloids (DTTAs). It was serendipitously observed that the addition of Co2+ to the medium resulted in a notable enhancement in DTTAs production in the T. longibrachiatum UN32 strain, accompanied by an upregulating effect on the expression of antioxidase-related genes. Hence, the objective of the present work was to ascertain whether ROS (intracellular levels of hydrogen peroxide) induced by Co2+ treatment has a beneficial or detrimental impact on DTTAs biosynthesis. A comparison of the intracellular levels of hydrogen peroxide (H2O2) and DTTAs treated with CoCl2 and CH3COOH revealed that CoCl2 was the optimal inducer for investigating the relationship between ROS formation and DTTAs production. This was due to the observation that ROS formation was reduced by approximately 4% and DTTAs production was increased by 12.55% in comparison to the CH3COOH treatment. The physiological results revealed that the introduction of Co2+ resulted in the oxidative damage and activation of the expression of intracellular superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). Furthermore, it was confirmed that ROS induced by Co2+ was beneficial to DTTAs production by adding exogenous ROS scavengers. The inclusion of all ROS scavengers, including vitamin C, tocopherol, melatonin, mannitol, and sesamol, resulted in a reduction in ROS accumulation and a concomitant decrease in DTTAs production. Specifically, the addition of melatonin at a concentration of 0.4 mg/L demonstrated significant effects, resulting in a 32.53% (P < 0.01) decrease in ROS accumulation and a 45.22% (P < 0.01) reduction in DTTAs production. Subsequently, the timelines of accumulation of intracellular H2O2 and DTTAs content indicated that ROS are also crucial for normal fermentation without CoCl2 addition. Specifically, the proper H2O2 dose for DTTAs accumulation is between 8.82 and 18.86 µmol/g. The present study offers the initial experimental evidence indicating that CoCl2 enhance DTTAs production during the culture of T. longibrachiatum UN32 via leading an increase in intracellular ROS, which is conductive to DTTAs production and can be inhibited by the ROS scavengers. Our results provide insights into the mechanistic study of DTTAs biosynthesis.
Assuntos
Alcaloides , Catalase , Cobalto , Peróxido de Hidrogênio , Estresse Oxidativo , Espécies Reativas de Oxigênio , Trichoderma , Espécies Reativas de Oxigênio/metabolismo , Cobalto/metabolismo , Cobalto/farmacologia , Trichoderma/metabolismo , Trichoderma/genética , Trichoderma/efeitos dos fármacos , Alcaloides/metabolismo , Alcaloides/biossíntese , Peróxido de Hidrogênio/metabolismo , Catalase/metabolismo , Catalase/genética , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Superóxido Dismutase/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Peroxidase/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genéticaRESUMO
Background: Neutrophils (polymorphonuclear leukocytes, PMNs) are the most abundant subtype of white blood cells and are among the main actors in the inflammatory response. Psoriatic arthritis (PsA) is a chronic inflammatory disease affecting both the axial and peripheral joints. Typically associated with psoriasis, PsA can also affect multiple systems and organs, including the nails and entheses. Despite the involvement of PMNs in PsA, their specific role in the disease remains poorly understood. This study aimed to characterize the biological functions of PMNs and neutrophil-related mediators in PsA patients. Materials and methods: 31 PsA patients and 22 healthy controls (HCs) were prospectively recruited. PMNs were isolated from peripheral blood and subjected to in vitro stimulation with lipopolysaccharide (LPS), N-Formylmethionyl-leucyl-phenylalanine (fMLP), tumor necrosis factor (TNF), phorbol 12-myristate 13-acetate (PMA), or control medium. Highly purified peripheral blood PMNs (>99%) were evaluated for activation status, reactive oxygen species (ROS) production, phagocytic activity, granular enzyme and neutrophil extracellular traps (NETs) release. Serum levels of matrix metalloproteinase-9 (MMP-9), myeloperoxidase (MPO), TNF, interleukin 23 (IL-23), and interleukin 17 (IL-17) were measured by ELISA. Serum Citrullinated histone H3 (CitH3) was measured as a NET biomarker. Results: Activated PMNs from PsA patients displayed reduced activation, decreased ROS production, and impaired phagocytic activity upon stimulation with TNF, compared to HCs. PMNs from PsA patients also displayed reduced granular enzyme (MPO) and NET release. Serum analyses revealed elevated levels of MMP-9, MPO, TNF, IL-23, IL-17, and CitH3 in PsA patients compared to HCs. Serum CitH3 levels positively correlated with MPO and TNF concentrations, and IL-17 concentrations were positively correlated with IL-23 levels in PsA patients. These findings indicate that PMNs from PsA patients show reduced in vitro activation and function, and an increased presence of neutrophil-derived mediators (MMP-9, MPO, TNF, IL-23, IL-17, and CitH3) in their serum. Conclusions: Taken together, our findings suggest that PMNs from PsA patients exhibit an "exhausted" phenotype, highlighting their plasticity and multifaceted roles in PsA pathophysiology.
Assuntos
Artrite Psoriásica , Armadilhas Extracelulares , Neutrófilos , Humanos , Artrite Psoriásica/imunologia , Masculino , Neutrófilos/imunologia , Neutrófilos/metabolismo , Feminino , Pessoa de Meia-Idade , Adulto , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/imunologia , Espécies Reativas de Oxigênio/metabolismo , Metaloproteinase 9 da Matriz/sangue , Metaloproteinase 9 da Matriz/metabolismo , Ativação de Neutrófilo , Biomarcadores/sangue , Peroxidase/sangue , Peroxidase/metabolismo , Citocinas/sangue , Citocinas/metabolismo , Estudos de Casos e Controles , FagocitoseRESUMO
Lead (Pb) exposure can induce molecular changes in plants, disrupt metabolites, and impact plant growth. Therefore, it is essential to comprehend the molecular mechanisms involved in Pb tolerance in plants to evaluate the long-term environmental consequences of Pb exposure. This research focused on maize as the test subject to study variations in biomass, root traits, genes, and metabolites under hydroponic conditions under Pb conditions. The findings indicate that high Pb stress significantly disrupts plant growth and development, leading to a reduction in catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) activities by 17.12, 5.78, and 19.38%, respectively. Conversely, Pb stress led to increase malondialdehyde (MDA) contents, ultimately impacting the growth of maize. The non-targeted metabolomics analysis identified 393 metabolites categorized into 12 groups, primarily consisting of organic acids and derivatives, organ heterocyclic compounds, lipids and lipid-like molecules and benzenoids. Further analysis indicated that Pb stress induced an accumulation of 174 metabolites mainly enriched in seven metabolic pathways, for example phenylpropanoid biosynthesis and flavonoid biosynthesis. Transcriptome analysis revealed 1933 shared differentially expressed genes (DEGs), with 1356 upregulated and 577 downregulated genes across all Pb treatments. Additionally, an integrated analysis identified several DEGs and differentially accumulated metabolites (DAMs), including peroxidase, alpha-trehalose, and D-glucose 6-phosphate, which were linked to cell wall biosynthesis. These findings imply the significance of this pathway in Pb detoxification. This comprehensive investigation, employing multiple methodologies, provides a detailed molecular-level insight into maize's response to Pb stress.
Assuntos
Regulação da Expressão Gênica de Plantas , Chumbo , Metabolômica , Plântula , Zea mays , Zea mays/genética , Zea mays/efeitos dos fármacos , Zea mays/metabolismo , Zea mays/fisiologia , Chumbo/toxicidade , Chumbo/metabolismo , Plântula/efeitos dos fármacos , Plântula/genética , Plântula/fisiologia , Plântula/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Transcriptoma/genética , Perfilação da Expressão Gênica , Malondialdeído/metabolismo , Superóxido Dismutase/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Estresse Fisiológico/genética , Catalase/metabolismo , Catalase/genética , Peroxidase/metabolismo , Peroxidase/genéticaRESUMO
Cathepsin C (CatC) is an enzyme which regulates the maturation of neutrophil serine proteases (NSPs) essential for neutrophil activation. Activated neutrophils are key players in the innate immune system, and are also implicated in the etiology of various inflammatory diseases. This study aims to demonstrate a therapeutic potential for CatC inhibitors against disorders in which activated neutrophil-derived neutrophil extracellular traps (NETs) play a significant role. We demonstrate that a CatC inhibitor, MOD06051, dose-dependently suppresses the cellular activity of NSPs, including neutrophil elastase (NE), in vitro. Neutrophils derived from MOD06051-administered rats exhibit significantly lower NE activity and NET-forming ability than controls. Furthermore, MOD06051 dose-dependently ameliorates vasculitis and significantly decreases NETs when administered to a rat model of myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody-associated vasculitis (AAV). These findings suggest that CatC inhibition is a promising strategy to reduce neutrophil activation and improve activated neutrophil-mediated diseases such as MPO-AAV.
Assuntos
Catepsina C , Armadilhas Extracelulares , Elastase de Leucócito , Ativação de Neutrófilo , Neutrófilos , Peroxidase , Catepsina C/metabolismo , Catepsina C/antagonistas & inibidores , Animais , Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Armadilhas Extracelulares/efeitos dos fármacos , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Ativação de Neutrófilo/efeitos dos fármacos , Humanos , Ratos , Elastase de Leucócito/metabolismo , Elastase de Leucócito/antagonistas & inibidores , Masculino , Peroxidase/metabolismo , Peroxidase/antagonistas & inibidores , Serina Proteases/metabolismo , Ratos Sprague-Dawley , Modelos Animais de Doenças , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologiaRESUMO
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 , MutaçãoRESUMO
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 RosanilinaRESUMO
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 FuncionalRESUMO
BACKGROUND: The unique size, physical and chemical properties, and ultra-high stability of nanozymes have attracted extensive attentions in sensing, but improvement of catalytic activity of the nanozymes is still an urgent issue. Given the ultra-high simulated enzyme activity of metal nanoparticles and the advantage of multi-enzyme catalysis, an Au-decorated MoS2 nanosheets (MoS2/Au NS) integrating the double peroxidase-like (POD) activity is developed. RESULTS: By optimizing and adjusting the density of AuNPs, as well as its morphology and other parameters, a monodisperse and high-density distribution of AuNPs on MoS2 nanosheets was obtained, which can greatly improve the POD-like activity of MoS2/Au NS. Nafion solution was applied to assist the modification of MoS2/Au NS on the electrode surface so as to improved its stability. An electrochemical H2O2 detection platform was constructed by modifying MoS2/Au NS nanozyme on the SPCE using the conductive Nafion solution. And the negatively charged sulfonic acid group can eliminate negatively charged electroactive substances to improve the specificity. Then ascorbic acid was used to stimulate tumor cells to produce H2O2 as therapeutic model, an ultrasensitive chronocoulometry detection for H2O2 in cell lysate was established. The logarithmically of ΔQ and the logarithmically of H2O2 concentration showed a good linear relationship between 1 µM and 500 mM, with a LOD value of 0.3 µM. SIGNIFICANCE: The developed H2O2 sensor has excellent stability, reproducibility (RSD = 2.3 %, n = 6) and selectivity, realized the quantitative detection of H2O2 in cell lysate. Compared with commercial fluorescence detection kits for H2O2 in cell lysate, it is worth mentioning that the electrochemical H2O2 sensor developed in this study is simpler and faster, with higher sensitivity and lower cost. This provides a potential substitute for disease diagnosis and treatment evaluation based on accurate detection of H2O2.
Assuntos
Antineoplásicos , Dissulfetos , Técnicas Eletroquímicas , Ouro , Peróxido de Hidrogênio , Nanopartículas Metálicas , Molibdênio , Ouro/química , Molibdênio/química , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Dissulfetos/química , Nanopartículas Metálicas/química , Técnicas Eletroquímicas/métodos , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/análise , Nanoestruturas/química , Limite de Detecção , Peroxidase/química , Peroxidase/metabolismo , Ensaios de Seleção de Medicamentos AntitumoraisRESUMO
Herein, the selenium (Se) modified gold nanoparticles (Se-AuNPs) was synthesized using cerium doped carbon dots (Ce-CDs) as a reducing agent and template. As desired, Se-AuNPs displays enhanced peroxidase (POD)-like activity in the presence of Hg2+. The mechanism for the enhanced activity was attributed to the increased affinity between Se-AuNPs-Hg2+ and the substrate, in which Se and Au elements have a strong binding capacity to Hg2+, forming Hg-Se bonds and Au-Hg amalgam to generate more ·OH. This POD-like activity of Se-AuNPs-Hg2+ correlates with the colorimetric reaction by the catalytic reaction between 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2. The oxidation of TMB was completely inhibited by the introduction of the reductive S2-. Based on the above findings, a strategy for the colorimetric detection of Hg2+ and S2- by Se-AuNPs was established with linear ranges of 0.33-66 µg/L and 0.625-75 µg/L, and low detection limits of 0.17 µg/L and 0.12 µg/L (3.3 δ/k), respectively. When the colorimetric probes for detection of Hg2+ and S2- was applied in environmental water samples, the recoveries were in the range of 90.3-108.0 %. This method will provide a new idea for the colorimetric detection strategy of Hg2+ due to the strong interaction between Hg and Se.