Simultaneous SERS Sensing of Cysteine and Homocysteine in Blood Based on the CBT-Cys Click Reaction: Toward Precisive Diagnosis of Schizophrenia.

At present, there is a lack of sufficiently specific laboratory diagnostic indicators for schizophrenia. Serum homocysteine (Hcy) levels have been found to be related to schizophrenia. Cysteine (Cys) is a demethylation product in the metabolism of Hcy, and they always coexist with highly similar structures in vivo. There are few reports on the use of Cys as a diagnostic biomarker for schizophrenia in collaboration with Hcy, mainly because the rapid, economical, accurate, and high-throughput simultaneous detection of Cys and Hcy in serum is highly challenging. Herein, a click reaction-based surface-enhanced Raman spectroscopy (SERS) sensor was developed for simultaneous and selective detection of Cys and Hcy. Through the efficient and specific CBT-Cys click reaction between the probe containing cyan benzothiazole and Cys/Hcy, the tiny methylene difference between the molecular structures of Cys and Hcy was converted into the difference between the ring skeletons of the corresponding products that could be identified by plasmonic silver nanoparticle enhanced molecular fingerprint spectroscopy to realize discriminative detection. Furthermore, the SERS sensor was successfully applied to the detection in related patient serum samples, and it was found that the combined analysis of Cys and Hcy can improve the diagnostic accuracy of schizophrenia compared to a single indicator.

Reversible Dual Fluorescence-Lifetime Imaging of Mitochondrial GSH and Microviscosity: Real-Time Evaluation of Ferroptosis Status.

Ferroptosis, as a new form of regulated cell death, is implicated in various physiological and pathological processes. Developing a single probe for an independent analysis of multiple analytes related to ferroptosis can provide more accurate information and simplify the detection procedures, but it faces great challenges. In this work, we develop a fluorescent probe for the simultaneous detection of GSH through ratiometric fluorescence response and microviscosity via a fluorescence lifetime model. Based on the reversible Michael addition reaction between GSH and unsaturated C═C bond, the probe responds reversibly to GSH with a ratiometric fluorescence variation and a fast response time (t1/2 = 4.7 s). At the same time, the probe is sensitive to environmental viscosity by changing its fluorescence lifetimes. The probe was applied to monitor the drug-induced ferroptosis process through both the classical Xc-/GSH/GPX4- and DHODH-mediated defense mechanisms. We hope that the probe will provide a useful molecular tool for the real-time live-cell imaging of GSH dynamics, which is benefit to unveiling related physiological and pathological processes.

Dual-mode optical biosensor based on multi-functional DNA structures for detecting bioactive small molecules.

Semiconducting polymer dots and hemin-functionalized DNA nanoflowers with excellent peroxidase-like activity and high fluorescent brightness are prepared for fluorescent/colorimetric dual-mode sensing of dopamine and glutathione as low as nM and µM, respectively. This biosensor is readily applied to the analysis of complicated biological samples with high selectivity and accuracy, which opens up promising prospects in clinical applications.

Protein intake affects erythrocyte glutathione synthesis in healthy adults aged ≥60 years in a repeated-measures trial.

BACKGROUND: Protein recommendations for older adults are based on nitrogen balance data from young adults. Physiological studies using the indicator amino acid oxidation method suggest they need 30% to 50% more protein than current recommendations. We herein present glutathione (GSH) as a physiological estimate of protein adequacy in older adults. OBJECTIVES: The objective was to measure GSH kinetics in response to varying protein intakes in a repeated-measures design in healthy adults aged ≥60 y using the precursor-product method. METHODS: Sixteen healthy older adults (n = 8 male and n = 8 female; body mass index ≤30 kg/m2) were studied. Each received 4 of 6 protein intakes in random order (0.66, 0.8, 0.9, 1.1, 1.3 and 1.5 g⋅kg-1⋅d-1). At each intake level, participants underwent isotope infusion studies of 7 h duration following a 3-d adaptation to the test level of protein. On the fourth day, GSH fractional (FSR) and absolute synthesis (ASR) rates were quantified by measuring the incorporation of U-[13C2-15N]glycine into GSH at isotopic steady state. A mixed-effect change-point regression model was used to determine a breakpoint in FSR and ASR. Secondary outcomes included plasma concentrations of oxidative stress markers, homocysteine, 5-L-oxoproline (5-OP), and urinary sulfate. The effect of secondary outcomes on GSH kinetics was analyzed using a joint linear mixed-effect model and Tukey's post hoc test. RESULTS: A protein intake of 1.08 g⋅kg-1⋅d-1 (95% confidence interval [CI]: 0.83, 1.32; Rm2 = 0.207; Rc2 = 0.671; P < 0.001) maximized GSH FSR. There was no effect of protein intake on concentrations of erythrocyte GSH, plasma homocysteine, oxidative stress markers, or 5-OP (P > 0.05). Protein intake had a positive effect on urinary sulfate excretion (P < 0.0001). CONCLUSION: A protein intake of 1.08 g⋅kg-1⋅d-1 from a high-quality protein maximized GSH synthesis in adults ≥60 y. This lends support to data suggesting a requirement higher than the current recommendation. This study was registered at clinicaltrials.gov as NCT02971046.

Synergism Variation between intracellular Glutathione, phycocyanin and SOD in microalgae by carbon quantum dot fluorescence.

Based on the use of CQDs as fluorescent probe and covalent coupling method to detect biological molecules with amino groups, to deeply analysis and detect the metabolism of Microcystis aeruginosa. The metabolic changes of carboxyl biomolecules in Microcystis aeruginosa were analyzed by covalent coupling method, including GSH, phycocyanin and SOD enzyme. The changes of GSH content and its correlation between phycocyanin, SOD were analyzed. The content of phycocyanin and SOD reached the maximum on the 65th day, and GSH was more sensitive to the growth and metabolism of microalgae. GSH plays an important role in reducing the external oxidative damage of microalgae cells. The synthesis of glutathione (GSH), GSH/GSSG mutual transformation, the production of phytochelating peptide (PC), the ASA-GSH cycle, and other physiological processes are interconnected. These interactions are crucial for preserving the antioxidant properties of microalgae and regulating redox-sensitive signal transduction.

Electrochemical detection of glutathione based on accelerated CRISPR/Cas12a trans-cleavage with MnO2 nanosheets.

The CRISPR/Cas12a system is accelerated by glutathione-mediated reduction of MnO2 nanosheets. By monitoring the trans-cleavage of the DNA probe, an electrochemical method for glutathione assay is fabricated, with the detection limit of 3.5 pM. It provides a promising tool for plasma analysis with satisfactory performance, indicating the broad application prospects of this glutathione assay.

Optimization of extraction and development of an LC-HRMS method to quantify glutathione and glutathione disulfide in white wine lees and yeast derivatives.

The antioxidant capacity of wine depends on its quality and aging potential. Aging on lees can improve this capacity thanks to the release of glutathione (GSH), as can the addition of yeast derivatives (YD). Therefore, the GSH potential of wine lees (WL) and YD requires investigation. We propose an optimized method to extract and quantify GSH from WL and YD. First, a method was developed to detect and quantify GSH and glutathione disulfide (GSSG) using LC-HRMS. Second, Box-Behnken response surface methodologies (RSM) were applied to both matrices. Results showed that the main parameter affecting GSH extraction efficiency was ethanol concentration. Quantitation of various samples revealed GSH concentrations of up to 900 µg/g for WL and 40 mg/g for YD. To our knowledge, the absolute quantitation of GSH/GSSG in these matrices has not been reported until now.

[Metabolic Stress of Red Blood Cells Induces Hemoglobin Glutathionylation].

Metabolic stress caused by a lack of glucose significantly affects the state of red blood cells, where glycolysis is the main pathway for the production of ATP. Hypoglycemia can be both physiological (occurring during fasting and heavy physical exertion) and pathological (accompanying a number of diseases, such as diabetes mellitus). In this study, we have characterized the state of isolated erythrocytes under metabolic stress caused by the absence of glucose. It was established that 24 h of incubation of the erythrocytes in a glucose-free medium to simulate blood plasma led to a two-fold decrease in the ATP level into them. The cell size, as well as intracellular sodium concentration increased. These findings could be the result of a disruption in ion transporter functioning because of a decrease in the ATP level. The calcium level remained unchanged. With a lack of glucose in the medium of isolated erythrocytes, there was no increase in ROS and a significant change in the level of nitric oxide, while the level of the main low-molecular weight thiol of cells, glutathione (GSH) decreased by almost 2 times. It was found that the metabolic stress of isolated red blood cells induced hemoglobin glutathionylation despite the absence of ROS growth. The cause was the lack of ATP, which led to a decrease in the level of GSH because of the inhibition of its synthesis and, probably, due to a decrease in the NADPH level required for glutathione (GSSG) reduction and protein deglutathionylation. Thus, erythrocyte metabolic stress induced hemoglobin glutathionylation, which is not associated with an increase in ROS. This may have an important physiological significance, since glutathionylation of hemoglobin changes its affinity for oxygen.

Pyrylium-based derivatization for rapid labeling and enhanced detection of thiol in mass spectrometry imaging.

Many endogenous antioxidants, including glutathione (GSH), cysteine (Cys), cysteinyl-glycine (Cys-Gly) and homocysteine (Hcy) possess free thiol functional groups. In most cases, matrix-assisted laser desorption ionization (MALDI) analyses of trace amounts of thiol compounds are challenging because of their instability and poor ionization properties. We present a mass spectrometry imaging (MSI) approach for mapping of thiol compounds on brain tissue sections. Our derivatization reagents 1-(2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethyl)-2,4,6-trimethylpyridinium (MTMP) and 1-(2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethyl)-2,4,5-triphenylpyridinium (MTPP) facilitate the covalent charge-tagging of molecules containing free thiol group for the selective and rapid detection of GSH synthesis and metabolic pathway related metabolites by MALDI-MSI. The developed thiol-specific mass spectrometry imaging method realizes the quantitative detection of exogenous N-acetylcysteine tissue sections, and the detection limit in mass spectrometry imaging could reach 0.05 ng. We illustrate the capabilities of the developed method to mapping of thiol compounds on brain tissue from the chronic social defeat stress (CSDS) depression model mice.

N-Acetylcysteine Displaces Glutathionyl-Moieties from Hg2+ and MeHg+ to Form More Hydrophobic Complexes at Near-Physiological Conditions.

The anthropogenic release of Hg is associated with an increased human exposure risk. Since Hg2+ and MeHg+ have a high affinity for thiols, their interaction with L-glutathione (GSH) within mammalian cells is fundamentally involved in their toxicological chemistry and excretion. To gain insight into the interaction of these mercurials with multiple small molecular weight thiols, we have investigated their competitive interactions with GSH and N-acetylcysteine (NAC) at near-physiological conditions, using a liquid chromatographic approach. This approach involved the injection of each mercurial onto a reversed-phase (RP)-HPLC column (37 °C) using a PBS buffer mobile phase containing 5.0 mM GSH to simulate cytosolic conditions with Hg being detected in the column effluent by an inductively coupled plasma atomic emission spectrometer (ICP-AES). When the 5.0 mM GSH mobile phase was amended with up to 10 mM NAC, gradually increasing retention times of both mercurials were observed. To explain this behavior, the experiment with 5.0 mM NAC and 5.0 mM GSH was replicated using 50 mM Tris buffer (pH 7.4), and the Hg-containing fractions were analyzed by electrospray ionization mass spectrometry. The results revealed the presence of Hg(GS)(NAC) and Hg(NAC)2 for Hg2+ and MeHg(GS) and MeHg(NAC) for MeHg+, which suggests that the coordination/displacement of GS-moieties from each mercurial by the more hydrophobic NAC can explain their retention behavior. Since the biotransformations of both mercurials were observed at near-physiological conditions, they are of toxicological relevance as they provide a biomolecular explanation for some results that were obtained when animals were administered with each mercurial and NAC.

The Effects of White Tea (Camellia Sinensis) and Infliximab Against Cisplatin- Induced Testicular Damage via Oxidative Stress and Apoptosis / Efectos del Té Blanco (Camellia Sinensis) e Infliximab Contra el Daño Testicular Inducido por Cisplatino a Través del Estrés Oxidativo y la Apoptosis

SUMMARY: Cisplatin (Cis) is an important chemotherapeutic agent used in cancer treatment. Males exposed to Cis were reported to exhibit testicular toxicity. Cis-induced testicular toxicity is mediated by oxidative stress, inflammation, testosterone inhibition and apoptosis. Accordingly, this study was conducted to evaluate the potential protective roles of infliximab (IFX), which is an anti- TNF-a agent, and of white tea (Camellia sinensis), which is known to possess antioxidant, anti-apoptotic, and anti-inflammatory effects, against Cis-induced testicular toxicity in rats. Rats were randomly assigned into five groups as follows: control group, Cisplatin (7 mg/kg) treatment group, Cisplatin (7 mg/kg) + infliximab (7 mg/kg) treatment group, cisplatin + white tea (WT) treatment group, and Cisplatin+ WT+IFX combined treatment group. In the present study, Cis exposure reduced the sperm count. It also increased testicular oxidative stress as well as the levels of inflammatory and apoptotic markers. Histopathological assays supported the biochemical findings. Treatment with IFX and/or WT restored testicular histology, preserved spermatogenesis, suppressed oxidative stress and apoptosis, and significantly ameliorated Cis-induced damage. It was concluded that white tea and infliximab could potentially serve as therapeutic options for the protection of testicular tissue against the harmful effects of Cis.

El cisplatino (Cis) es un importante agente quimioterapéutico utilizado en el tratamiento del cáncer. Se informó que los hombres expuestos a Cis exhibieron toxicidad testicular. La toxicidad testicular inducida por Cis está mediada por el estrés oxidativo, la inflamación, la inhibición de la testosterona y la apoptosis. En consecuencia, este estudio se realizó para evaluar las posibles funciones protectoras de infliximab (IFX), un agente anti-TNF-α, y del té blanco (Camellia sinensis), conocido por sus propiedades antioxidantes, antiapoptóticas y anti-TNF-α -efectos inflamatorios, contra la toxicidad testicular inducida por Cis en ratas. Cinco grupos de ratas se asignaron al azar de la siguiente manera: grupo control, grupo de tratamiento con cisplatino (7 mg/ kg), grupo de tratamiento con cisplatino (7 mg/kg) + infliximab (7 mg/kg), grupo de tratamiento con cisplatino + té blanco (WT), y grupo de tratamiento combinado Cisplatino+ WT+IFX. En el presente estudio, la exposición a Cis redujo el conteo de espermatozoides. También aumentó el estrés oxidativo testicular, así como los niveles de marcadores inflamatorios y apoptóticos. Los ensayos histopatológicos respaldaron los hallazgos bioquímicos. El tratamiento con IFX y/o WT restauró la histología testicular, preservó la espermatogénesis, suprimió el estrés oxidativo y la apoptosis, y mejoró significativamente el daño inducido por Cis. Se concluyó que el té blanco y el infliximab podrían potencialmente servir como opciones terapéuticas para la protección del tejido testicular contra los efectos nocivos de Cis.

In vivo monitoring of glutathione in a live rat brain based on the ratiometric signal output of 2D Cu-TCPP(Fe) nanosheets.

Herein, a novel ratiometric electrochemical platform was developed for in vivo analysis of GSH based on the dual signal output of 2D Cu-TCPP(Fe) nanosheets. Our method with high selectivity and high accuracy enabled GSH monitoring in a live rat brain, and accurate GSH concentrations were firstly reported in different brain regions upon global cerebral ischemia.

Emission enhanced fluorometric biosensor by functionalized carbon polymer dots for glutathione detection in human real samples and molecular logic gate operation.

Glutathione (GSH), an active peptide, plays pivotal roles in many physiological processes and detection of GSH inside of human body is of great importance for the playing of its biological effects. Here silver-phosphorus co-doped carbonized polymer dots (Ag@PCPDs) were prepared via solvothermal treatment of citric acid and phytic acid in the presence of Ag+ for GSH determination. The physicochemical and optical performance of the Ag@PCPDs were characterized by X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared (FT-IR), X-ray powder diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), fluorescence spectroscopy and ultraviolet-visible (UV-Vis) spectroscopy analyses. The prepared Ag@PCPDs have outstanding water solubility with high monodispersity (7.81 ± 0.31 nm) and exhibited excellent optical properties with excitation-dependent emission, high photostability, pH, and ionic strength tolerance. An optimized excitation at 358 nm, the Ag@PCPDs showed strong photoluminescent (PL) emission at 456 nm with a PL quantum yield (QYs) of 15.6%. Furthermore, the Ag@PCPDs were used as a PL sensing platform for detection GSH in a linear range of 0-200 µM with a low limit of detection at 0.68 µM. In addition, the proposed system can construct molecular logic gates with GSH and Fe3+ ions as the chemical inputs and PL emissions as the output. And the Ag@PCPDs were successfully used for GSH determination in real samples resulting in high sensitivity and satisfactory recoveries (92.81--107.45%). More importantly, the Ag@PCPDs showed low cytotoxicity at 500 µg/mL and superior cell imaging capability in HeLa cells, which offer a new path for detection and categorization of GSH in biomedical applications.

A dual-channel sensor array for discrimination of biothiols based on manganese dioxide nanosheets.

A dual-signal sensor array for highly sensitive identification of biothiols is reported based on different optical responses of MnO2/curcumin (CUR) system to different biothiols. The addition of MnO2 nanosheets (MnO2 NSs) quenches the fluorescence of CUR, and the color of the mixture changes from yellow to brown. In the presence of reductive biothiols, MnO2 NSs are etched and lose their fluorescence quenching ability, resulting in an increase in the fluorescence intensity of CUR at 540 nm and a decrease in the absorbance at 430 nm. The sensor array generates specific response modes based on the varying reduction abilities of different biothiols, which can be distinguished by linear discriminant analysis (LDA). The sensor array successfully distinguished five biothiols (glutathione (GSH), dithiothreitol (DTT), cysteine (Cys), mercaptoethanol (ME), and homocysteine (Hcy)) across a wide concentration range (1 µM-100 µM) and biothiol mixtures with varing molar ratios.

Predicting lifespan-extending chemical compounds for C. elegans with machine learning and biologically interpretable features.

Recently, there has been a growing interest in the development of pharmacological interventions targeting ageing, as well as in the use of machine learning for analysing ageing-related data. In this work, we use machine learning methods to analyse data from DrugAge, a database of chemical compounds (including drugs) modulating lifespan in model organisms. To this end, we created four types of datasets for predicting whether or not a compound extends the lifespan of C. elegans (the most frequent model organism in DrugAge), using four different types of predictive biological features, based on: compound-protein interactions, interactions between compounds and proteins encoded by ageing-related genes, and two types of terms annotated for proteins targeted by the compounds, namely Gene Ontology (GO) terms and physiology terms from the WormBase's Phenotype Ontology. To analyse these datasets, we used a combination of feature selection methods in a data pre-processing phase and the well-established random forest algorithm for learning predictive models from the selected features. In addition, we interpreted the most important features in the two best models in light of the biology of ageing. One noteworthy feature was the GO term "Glutathione metabolic process", which plays an important role in cellular redox homeostasis and detoxification. We also predicted the most promising novel compounds for extending lifespan from a list of previously unlabelled compounds. These include nitroprusside, which is used as an antihypertensive medication. Overall, our work opens avenues for future work in employing machine learning to predict novel life-extending compounds.

Colorimetric sensor arrays for antioxidant recognition based on Co3O4 dual-enzyme activities.

Antioxidants are considered as essential compounds for monitoring human health. In this work, a colorimetric sensor array was developed using oxidase-like (OXD) and peroxidase-like (POD) activities of Co3O4 nanoflowers as sensing elements, together with a substrate, 3,3',5,5'-tetramethylbenzidine dihydrochloride (TMB), as a signal reader to effectively identify different antioxidants. In the presence of Co3O4, colorless TMB can be oxidized into blue oxTMB to different degrees in the presence and absence of H2O2. Interestingly, after the addition of antioxidants, the sensor array showed cross-reactions, and different changes in color and absorbance were observed, as TMB and antioxidants competed for binding. Different colorimetric responses were obtained on the sensor array and identified by linear discriminant analysis (LDA). The LDA result indicated that the sensor array can be used to distinguish 4 antioxidants, namely, dopamine (DA), glutathione (GSH), ascorbic acid (AA), and cysteine (Cys) at seven different concentrations, namely, 10, 20, 30, 50, 100, 200, and 250 nM. Different concentrations of antioxidants and proportions of mixed antioxidants were determined. This demonstrates the potential application of sensor arrays in diagnosis and food monitoring.

A novel SERS sensor array based on AuNRs and AuNSs inverse-etching for the discrimination of five antioxidants.

Antioxidants play an important role in life health and food safety. Herein, an inverse-etching platform based on gold nanorods (AuNRs) and gold nanostars (AuNSs) for high-throughput discrimination of antioxidants was constructed. Under the action of hydrogen peroxide (H2O2) and horseradish peroxidase (HRP), 3,3',5,5'-tetramethylbenzidine (TMB) would be oxidized to TMB+ or TMB2+. HRP reacts with H2O2 to release oxygen free radicals, which then react with TMB. Au nanomaterials can react with TMB2+, at the same time, Au was oxidized into Au (I), leading to the etching of the shape. Antioxidants, with good reduction ability, would prevent the further oxidation of TMB+ to TMB2+. So the presence of antioxidants will prevent further oxidation while avoiding the etching of Au in the catalytic oxidation process, thereby achieved inverse etching. Distinctive surface enhanced Raman scattering (SERS) fingerprint of five antioxidants were obtained based on the differential ability to scavenge free radicals. Five antioxidants, including ascorbic acid (AA), melatonin (Mel), glutathione (GSH), tea polyphenols (TPP), and uric acid (UA) were successfully distinguished by using linear discriminant analysis (LDA), heat map analysis and hierarchical cluster analysis (HCA). The study exhibits an effective inverse-etching based SERS sensor array for the response of antioxidants, which has great reference value in the field of human disease and food detection.

[Toxicity attenuation processing technology and mechanism of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction].

This study explored toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction for the first time, and further explored its detoxification mechanism. Nine processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction were prepared by orthogonal experiment with three factors and three levels. Based on the decrease in the content of the main hepatotoxic component diosbulbin B before and after processing of Rhizoma Dioscoreae Bulbiferae by high-performance liquid chromatography, the toxicity attenuation technology was preliminarily screened out. On this basis, the raw and representative processed products of Rhizoma Dioscoreae Bulbiferae were given to mice by gavage with 2 g·kg~(-1)(equival to clinical equivalent dose) for 21 d. The serum and liver tissues were collected after the last administration for 24 h. The serum biochemical indexes reflecting liver function and liver histopathology were combined to further screen out and verify the proces-sing technology. Then, the lipid peroxidation and antioxidant indexes of liver tissue were detected by kit method, and the expressions of NADPH quinone oxidoreductase 1(NQO1) and glutamate-cysteine ligase(GCLM) in mice liver were detected by Western blot to further explore detoxification mechanism. The results showed that the processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reduced the content of diosbulbin B and improved the liver injury induced by Rhizoma Dioscoreae Bul-biferae to varying degrees, and the processing technology of A_2B_2C_3 reduced the excessive levels of alanine transaminase(ALT) and aspartate transaminase(AST) induced by raw Rhizoma Dioscoreae Bulbiferae by 50.2% and 42.4%, respectively(P<0.01, P<0.01). The processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reversed the decrease protein expression levels of NQO1 and GCLM in the liver of mice induced by raw Rhizoma Dioscoreae Bulbiferae to varying degrees(P<0.05 or P<0.01), and it also reversed the increasing level of malondialdehyde(MDA) and the decreasing levels of glutathione(GSH), glutathione peroxidase(GPX), and glutathione S-transferase(GST) in the liver of mice(P<0.05 or P<0.01). In summary, this study shows that the optimal toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction is A_2B_2C_3, that is, 10% of Paeoniae Radix Alba decoction is used for moistening Rhizoma Dioscoreae Bulbiferae and processed at 130 ℃ for 11 min. The detoxification mechanism involves enhancing the expression levels of NQO1 and GCLM antio-xidant proteins and related antioxidant enzymes in the liver.

Simultaneous determination of 2-(3-hydroxy-5-phosphonooxymethyl-2-methyl-4-pyridyl)-1,3-thiazolidine-4-carboxylic acid and main plasma aminothiols by HPLC-UV based method.

The report presents the first method for simultaneous determination of plasma 2-(3-hydroxy-5-phosphonooxymethyl-2-methyl-4-pyridyl)-1,3-thiazolidine-4-carboxylic acid (HPPTCA), an adduct of cysteine (Cys) and active form of vitamin B6 pyridoxal 5'-phosphate (PLP), as well as total low molecular-weight thiols content, including Cys, homocysteine (Hcy), cysteinyl-glycine (Cys-Gly), and glutathione (GSH). The assay is based on high performance liquid chromatography coupled with ultraviolet detection (HPLC-UV) and involves disulfides reduction with tris(2-carboxyethyl)phosphine (TCEP), derivatization with 2-chloro-1-methylquinolinium tetrafluoroborate (CMQT) followed by sample deproteinization with perchloric acid (PCA). The chromatographic separation of obtained stable UV-absorbing derivatives is achieved on ZORBAX SB-C18 (150 × 4.6 mm, 5.0 µm) column using gradient elution with eluent consisted of 0.1 mol/L trichloroacetic acid (TCA), pH 1.7 and acetonitrile (ACN), delivered at a flow rate 1 mL/min. Under these conditions, the analytes are separated within 14 min at room temperature, and quantified by monitoring at 355 nm. Regarding HPPTCA, the assay linearity was demonstrated within a 1-100 µmol/L in plasma and the lowest concentration on the calibration curve was recognized as the limit of quantification (LOQ). The accuracy ranged from 92.74 to 105.57% and 95.43 to 115.73%, while precision varied from 2.48 to 6.99% and 0.84 to 6.98% for intra- and inter-day measurements, respectively. The utility of the assay was proved by application to plasma samples delivered by apparently healthy donors (n = 18) in which the HPPTCA concentration ranged from 19.2 to 65.6 µmol/L. The HPLC-UV assay provides complementary tool for routine clinical analysis, facilitating further studies on the role of aminothiols and HPPTCA in living systems.

Comparative assessment of green and chemically synthesized glutathione capped silver nanoparticles for antioxidant, mosquito larvicidal and eco-toxicological activities.

A comparative assessment of AgNPs synthesized through three different routes viz. clove bud extract mediated AgNPs, sodium borohydride AgNPs and Glutathione (GSH) capped AgNPs for antioxidant and mosquito larvicidal activities was the major focus of the present study. The nanoparticles were characterized using UV-VIS spectrophotometry, dynamic light scattering (DLS), X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis. Characterization studies revealed the synthesis of stable, crystalline AgNPs measuring 28 nm, 7 nm and 36 nm for green, chemical and GSH-capped AgNPs respectively. FTIR analysis exhibited the surface functional moieties that were responsible for reduction, capping and stabilizing AgNPs. Antioxidant activity was found to be 74.11%, 46.62% and 58.78% for clove, borohydride and GSH-capped AgNPs respectively. Mosquito larvicidal bioactivity of AgNPs against Aedes aegypti IIIrd instar larvae depicted clove AgNPs being most effective (LC50-4.9 ppm, LC90-30.2 ppm) followed by GSH-capped (LC50-20.13 ppm, LC90-46.63 ppm) and borohydride AgNPs (LC50-13.43 ppm, LC90-160.19 ppm) after 24 h. Toxicity screening against aquatic model Daphnia magna revealed Clove mediated and GSH-capped AgNPs to be safer as compared to the borohydride AgNPs. It may be envisaged that green and capped AgNPs may be further explored for diverse biomedical and therapeutic applications.