Influence of circulating nesfatin-1, GSH and SOD on insulin secretion in the development of T2DM.

Aims: To evaluate the correlation of nesfatin-1, GSH and SOD levels with ß-cell insulin secretion and their influence on insulin secretion in the development of type 2 diabetes mellitus (T2DM). Materials and methods: 75 patients with T2DM, 67 with prediabetes and 37 heathy participants were recruited in this study. Serum levels of nesfatin-1, GSH and SOD were quantified and statistically analyzed. Results: The levels of nesfatin-1, GSH and SOD in T2DM were significantly decreased (P < 0.001) compared to either in prediabetes or in healthy control, and significant reduction of these biomarkers was also observed in prediabetes when compared to the control (P < 0.001). Circulating nesfatin-1, GSH and SOD were not only strongly correlated with ß-cell insulin secretion, but also exerted remarkable influence on the secretion. Conclusion: Serum nesfatin-1, GSH and SOD are important factors involving insulin secretion in the development of T2DM, which may help provide new ideas for forthcoming investigations on the roles of these factors in pathogenesis of T2DM, as well as for active prediction and prevention of prediabetes before it develops into overt T2DM.

Mitochondrial DNA and Epigenetics: Investigating Interactions with the One-Carbon Metabolism in Obesity.

Mitochondrial DNA copy number (mtDNAcn) has been proposed for use as a surrogate biomarker of mitochondrial health, and evidence suggests that mtDNA might be methylated. Intermediates of the one-carbon cycle (1CC), which is duplicated in the cytoplasm and mitochondria, have a major role in modulating the impact of diet on the epigenome. Moreover, epigenetic pathways and the redox system are linked by the metabolism of glutathione (GSH). In a cohort of 101 normal-weight and 97 overweight/obese subjects, we evaluated mtDNAcn and methylation levels in both mitochondrial and nuclear areas to test the association of these marks with body weight, metabolic profile, and availability of 1CC intermediates associated with diet. Body composition was associated with 1CC intermediate availability. Reduced levels of GSH were measured in the overweight/obese group (p = 1.3∗10-5). A high BMI was associated with lower LINE-1 (p = 0.004) and nominally lower methylenetetrahydrofolate reductase (MTHFR) gene methylation (p = 0.047). mtDNAcn was lower in overweight/obese subjects (p = 0.004) and independently correlated with MTHFR methylation levels (p = 0.005) but not to LINE-1 methylation levels (p = 0.086). DNA methylation has been detected in the light strand but not in the heavy strand of the mtDNA. Although mtDNA methylation in the light strand did not differ between overweight/obese and normal-weight subjects, it was nominally correlated with homocysteine levels (p = 0.035) and MTHFR methylation (p = 0.033). This evidence suggests that increased body weight might perturb mitochondrial-nuclear homeostasis affecting the availability of nutrients acting as intermediates of the one-carbon cycle.

Effect of an Extract from the Egyptian Sea Cucumber, Bohadschia marmorata, on Methotrexate-Induced Hepatorenal Toxicity in Male Mice.

BACKGROUND: The sea cucumber, Bohadschia marmorata, is a marine echinoderm consumed and used as a medication. Extract of this species displays a broad spectrum of bioactivity, such as antifungal, antibacterial, immunomodulatory, and cytotoxic properties. This investigation explored sea cucumber extract for hepatorenal protection against the toxicity of methotrexate (MTX). METHODS: Four groups of mice were divided into G1: control, G2: MTX treated, G3: B. marmorata extract-treated daily for 14 days, and G4: B. marmorata extract and MTX treated. RESULTS AND CONCLUSIONS: Biochemical analysis and histopathological examination of liver tissue showed that administration of MTX increased serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), lowered levels of serum albumin, total protein, Superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Administration of B. marmorata extract to MTX- injected mice significantly reversed the increase in serum levels of liver enzymes and induced a significant elevation in serum albumin and total protein levels. SOD, CAT, and GSH levels returned to nearly normal levels. Histopathological examination indicated fewer signs of toxicity in liver and kidney tissues of mice treated with both extract and MTX compared to MTX treatment alone. An extract of B. marmorata will protect mice from hepatorenal toxicity induced by MTX.

Plasma Glutathione and Prodromal Parkinson's Disease Probability.

BACKGROUND: A decrease in glutathione (GSH) levels is considered one of the earliest biochemical changes in Parkinson's disease (PD). OBJECTIVE: The authors explored the potential role of plasma GSH as a risk/susceptibility biomarker for prodromal PD (pPD) by examining its longitudinal associations with pPD probability trajectories. METHODS: A total of 405 community-dwelling participants (median age [interquartile range] = 73.2 [7.41] years) without clinical features of parkinsonism were followed for a mean (standard deviation) of 3.0 (0.9) years. RESULTS: A 1 µmol/L increase in plasma GSH was associated with 0.4% (95% confidence interval [CI], 0.1%-0.7%; P = 0.017) less increase in pPD probability for 1 year of follow-up. Compared with participants in the lowest GSH tertile, participants in the highest GSH tertile had a 12.9% (95% CI, 22.4%-2.2%; P = 0.020) slower rate of increase of pPD probability for 1 year of follow-up. CONCLUSION: Plasma GSH was associated with pPD probability trajectories; therefore, it might assist in the identification of individuals who are likely to reach the threshold for pPD diagnosis more rapidly. © 2021 International Parkinson and Movement Disorder Society.

Cardioprotective effects of amiodarone in a rat model of epilepsy-induced cardiac dysfunction.

Cardiac dysfunction is one of the leading causes of death in epilepsy. The anti-arrhythmic drug, amiodarone, is under investigation for its therapeutic effects in epilepsy. We aimed to evaluate the possible effects of amiodarone on cardiac injury during status epilepticus, as it can cause prolongation of the QT interval. Five rat groups were enrolled in the study; three control groups (1) Control, (2) Control-lithium and (3) Control-Amio, treated with 150 mg/kg/intraperitoneal amiodarone, (4) Epilepsy model, induced by sequential lithium/pilocarpine administration, and (5) the epilepsy-Amio group. The model group expressed a typical clinical picture of epileptiform activity confirmed by the augmented electroencephalogram alpha and beta spikes. The anticonvulsive effect of amiodarone was prominent, it diminished (p < 0.001) the severity of seizures and hence, deaths and reduced serum noradrenaline levels. In the model group, the electrocardiogram findings revealed tachycardia, prolongation of the corrected QT (QTc) interval, depressed ST segments and increased myocardial oxidative stress. The in-vitro myocardial performance (contraction force and - (df/dt)max ) was also reduced. Amiodarone decreased (p < 0.001) the heart rate, improved ST segment depression, and myocardial contractility with no significant change in the duration of the QTc interval. Amiodarone preserved the cardiac histological structure and reduced the myocardial injury markers represented by serum Troponin-I, oxidative stress and IL-1. Amiodarone pretreatment prevented the anticipated cardiac injury induced during epilepsy. Amiodarone possessed an anticonvulsive potential, protected the cardiac muscle and preserved its histological architecture. Therefore, amiodarone could be recommended as a protective therapy against cardiac dysfunction during epileptic seizures with favourable effect on seizure activity.

Altitude acclimatization via hypoxia-mediated oxidative eustress involves interplay of protein nitrosylation and carbonylation: A redoxomics perspective.

AIM: Hypoxia is an important feature of multiple diseases like cancer and obesity and also an environmental stressor to high altitude travelers. Emerging research suggests the importance of redox signaling in physiological responses transforming the notion of oxidative stress into eustress and distress. However, the behavior of redox protein post-translational modifications (PTMs), and their correlation with stress acclimatization in humans remains sketchy. Scant information exists about modifications in redoxome during physiological exposure to environmental hypoxia. In this study, we investigated redox PTMs, nitrosylation and carbonylation, in context of extended environmental hypoxia exposure. METHODS: The volunteers were confirmed to be free of any medical conditions and matched for age and weight. The human global redoxome and the affected networks were investigated using TMT-labeled quantitative proteo-bioinformatics and biochemical assays. The percolator PSM algorithm was used for peptide-spectrum match (PSM) validation in database searches. The FDR for peptide matches was set to 0.01. 1-way ANOVA and Tukey's Multiple Comparison test were used for biochemical assays. p-value<0.05 was considered statistically significant. Three independent experiments (biological replicates) were performed. Results were presented as Mean ± standard error of mean (SEM). KEY FINDINGS: This investigation revealed direct and indirect interplay between nitrosylation and carbonylation especially within coagulation and inflammation networks; interlinked redox signaling (via nitrosylation­carbonylation); and novel nitrosylation and carbonylation sites in individual proteins. SIGNIFICANCE: This study elucidates the role of redox PTMs in hypoxia signaling favoring tolerance and survival. Also, we demonstrated direct and indirect interplay between nitrosylation and carbonylation is crucial to extended hypoxia tolerance.

Modulation of bovine serum albumin aggregation by glutathione functionalized MoS2 quantum dots.

In present study, a novel glutathione functionalized MoS2 quantum dots (GSH-MoS2 QDs) was synthesized from sodium molybdate dehydrate and glutathione by using a one-pot hydrothermal method. After they were characterized, the influence of GSH-MoS2 QDs on amyloid aggregation of bovine serum albumin (BSA) was investigated by various analytical methods including thioflavin T fluorescence assay, circular dichroism and transmission electron microscope. Moreover, the effect of GSH-MoS2 QDs on cytotoxicity induced by BSA amyloid fibrils and cell penetration were evaluated by MTT assay and confocal fluorescence imaging, respectively. The results indicated that the GSH-MoS2 QDs not only had good water solubility, excellent biocompatibility and low cytotoxicity, but also could obviously inhibit the aggregation of BSA and depolymerize the formed BSA aggregates. The data obtained from this work demonstrated that the GSH-MoS2 QDs is expected to become a candidate drug for the treatment of amyloid-related diseases.

A novel design of multiple ligands for ultrasensitive colorimetric chemosensor of glutathione in plasma sample.

In this study, we developed a novel colorimetric chemosensor for selective and sensitive recognition of Glutathione (GSH) using a simple binary mixture of commercially accessible and inexpensive metal receptors with names, Bromo Pyrogallol Red (BPR) and Xylenol Orange (XO). This procedure is based on the synergistic coordination of BPR and XO with cerium ion (Ce3+) for the recognition of GSH over other available competitive amino acids (AAs) especially thiol species in aqueous media. Generally, cysteine (Cys) and homocysteine (hCys) can seriously interfere with the detection of GSH among common biological species because they possess similar chemical behavior. Using all the information from 1HNMR and FT-IR studies, the proposed interaction is presented in which GSH acts as a tri-dentate ligand with three N donor atoms in conjunction with BPR and XO as mono and bi-dentate ligands respectively. This approach opens a path for selective detection of other AAs by argumentatively selecting the ensemble of mixed organic ligands from commercially available reagents, thereby eliminating the need for developing synthetic receptors, sample preparation, organic solvent mixtures, and expensive equipment. Evaluating the feasibility of the existing method was led to the determination of GSH in human plasma samples.

Ginger honey affects cortisol, estrogen and glutathione levels; preliminary study to target preconceptional women.

OBJECTIVE: This study was aimed to determine the effect of ginger honey supplementation on cortisol, glutathione, and estrogen levels. The study was conducted on mice that had not yet experienced conception, and prior stress induction was carried out so that they could be continued for human trials at the preconception stage and subjects who experienced mild stress. METHOD: It was an in vivo study, pretest-posttest control group design. The sample of this study was 2-3 months female Balb/c mice, divided into negative control and ginger honey intervention as much as 28mg/20g BW for 14 days-the ELISA method used to examine cortisol hormone, glutathione levels, and estrogen levels. The mice chosen were those that had never experienced conception, and before the intervention, swimming activities were carried out on the mice until they showed symptoms of stress. RESULTS: Results show 42mg/20g BW of ginger honey administration for 14 days increased 1.892 ng/dl of cortisol (p = 0.165), increased 2.438 ng/dl of glutathione (p=0.002), and also increased 22.754ng/ml estrogen levels in induced stress Balb/c female mice (p=0.001). CONCLUSION: Ginger honey did not affect reducing cortisol levels but increasing glutathione and estrogen levels significantly. Ginger honey supplements are the potential to use as complementary therapies.

Plasma S-Adenosylmethionine Is Associated with Lung Injury in COVID-19.

OBJECTIVE: S-Adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH) are indicators of global transmethylation and may play an important role as markers of severity of COVID-19. METHODS: The levels of plasma SAM and SAH were determined in patients admitted with COVID-19 (n = 56, mean age = 61). Lung injury was identified by computed tomography (CT) in accordance with the CT0-4 classification. RESULTS: SAM was found to be a potential marker of lung damage risk in COVID-19 patients (SAM > 80 nM; CT3,4 vs. CT 0-2: relative ratio (RR) was 3.0; p = 0.0029). SAM/SAH > 6.0 was also found to be a marker of lung injury (CT2-4 vs. CT0,1: RR = 3.47, p = 0.0004). There was a negative association between SAM and glutathione level (ρ = -0.343, p = 0.011). Interleukin-6 (IL-6) levels were associated with SAM (ρ = 0.44, p = 0.01) and SAH (ρ = 0.534, p = 0.001) levels. CONCLUSIONS: A high SAM level and high methylation index are associated with the risk of lung injury in patients with COVID-19. The association of SAM with IL-6 and glutathione indicates an important role of transmethylation in the development of cytokine imbalance and oxidative stress in patients with COVID-19.

Dietary Antioxidant Capacity Promotes a Protective Effect against Exacerbated Oxidative Stress in Women Undergoing Adjuvant Treatment for Breast Cancer in a Prospective Study.

Breast cancer (Bca) is the most common type of cancer among women worldwide, and oxidative stress caused by adjuvant treatment may be decreased by antioxidant intake. The aim of this study is to investigate the associations between Dietary antioxidant Capacity (DaC) and oxidation and antioxidant biomarkers in women undergoing adjuvant treatment (AT) for Bca. This prospective study had a sample of 70 women (52.2 ± 10.7 y). DaC (mmol/g) was calculated using nutritional data obtained from a Food Frequency Questionnaire, and blood was collected to measure the oxidation and antioxidant biomarkers at baseline (T0), and after AT (T1). Carbonylated protein levels were inversely associated with DaC at T1 (p = 0.004); women showed an increased risk of having increment on lipid hydroperoxides and thiobarbituric acid reactive substances (TBARS), and decrement on ferric reducing antioxidant power (FRAP) and reduced glutathione after AT, in response to lowered DaC (p < 0.05). Carbonylated proteins, TBARS and FRAP levels remained stable between the periods for women at the 3rd DaC tertile at T1, differentiating them from those at the 1st tertile, who showed negative changes in these biomarkers (p < 0.04). DaC may be beneficial for women undergoing AT for Bca, since it promoted a reduction in oxidative stress.

Antioxidant status in relation to heavy metals induced oxidative stress in patients with polycystic ovarian syndrome (PCOS).

Polycystic ovary syndrome (PCOS) is a global health concern for women of reproductive age, as 6.5% of women worldwide are affected by this syndrome. PCOS is marked by hyperandrogenism, anovulation, menstrual abnormalities, and polycystic ovaries. Metals such as arsenic, cadmium, lead and mercury are considered to be systemic toxicants/human carcinogens and seem to have devastating effects on humans, even at minimal exposures. One of the probable aetiological factors for PCOS has been identified as oxidative stress. In view of the probable associations among oxidative stress, metal toxicity and PCOS, the present study examined the role of heavy metals in the generation of oxidative stress among females. This prospective study included 106 women (56 women diagnosed with PCOS and 50 women who were not diagnosed with PCOS as control women). There were no significant differences in the sociodemographic characteristics between the two groups except for the irregularity of menses and the presence of acne. The serum As, Cd, Pb, and Hg levels increased and the serum glutathione (GSH) and superoxide dismutase (SOD) levels diminished significantly in the PCOS group compared to the control group at P < 0.001. The SOD levels were negatively correlated with the As and Pb levels at P < 0.05. Additionally, the PCOS group exhibited a strong negative correlation between the GSH and As levels (P < 0.01), GSH and Pb levels (P < 0.05) and GSH and Hg levels (P < 0.01). Furthermore, the As levels were positively correlated with increased levels of Cd, Pb and Hg among PCOS women. Significant positive correlations were observed between Pb and Cd and between Cd and Hg at P < 0.001. The outcome of the study provides clear insight into the role of metal-induced oxidative stress, which plays a vital role in the pathophysiology underlying PCOS and suggests the use of these markers as prognostic tools to reduce the consequences of high-risk exposure to these metals among females.

Plant-Based, Antioxidant-Rich Snacks Elevate Plasma Antioxidant Ability and Alter Gut Bacterial Composition in Older Adults.

Plant-rich diets alleviate oxidative stress and gut dysbiosis and are negatively linked to age-associated chronic disorders. This study examined the effects of consuming plant-based, antioxidant-rich smoothies and sesame seed snacks (PBASS) on antioxidant ability and gut microbial composition in older adults. Healthy and sub-healthy older adults (n = 42, 79.7 ± 8.6 years old) in two senior living facilities were given PBASS for 4 months. Blood and fecal samples were collected from these individuals at the baseline and after 2 and 4 months of PBASS consumption. After 2 months, serum levels of albumin and high-density lipoprotein-cholesterol and the ratio of reduced to oxidized glutathione (GSH/GSSG) had increased significantly and erythrocytic glutathione, GSH/GSSG and superoxide dismutase activity had decreased significantly compared with baseline levels (p < 0.05). After 4 months, red blood cells, hematocrit, serum blood urea nitrogen and erythrocyte glutathione peroxidase activity had decreased significantly, whereas plasma and erythrocyte protein-bound sulfhydryl groups had increased significantly. Furthermore, plasma glutathione and total antioxidant capacity were significantly greater after 2 months and increased further after 4 months of PBASS consumption. The results of next generation sequencing showed that PBASS consumption prompted significant decreases in observed bacterial species, their richness, and the abundance of Actinobacteria and Patescibacteria and increases in Bacteroidetes in feces. Our results suggest that texture-modified, plant-based snacks are useful nutrition support to benefit healthy ageing via the elevation of antioxidant ability and alteration of gut microbiota.

The Prognostic Role of Glutathione and Its Related Antioxidant Enzymes in the Recurrence of Hepatocellular Carcinoma.

The imbalance of high oxidative stress and low antioxidant capacities is thought to be a significant cause of the development and progression of hepatocellular carcinoma (HCC). However, the impact of oxidative stress, glutathione (GSH), and its related antioxidant enzymes on the recurrence of HCC has not been investigated. The purpose of this study was to compare the changes to oxidative stress and GSH-related antioxidant capacities before and after tumor resection in patients with HCC recurrence and non-recurrence. We also evaluated the prognostic significance of GSH and its related enzymes in HCC recurrence. This was a cross-sectional and follow-up study. Ninety-two HCC patients who were going to receive tumor resection were recruited. We followed patients' recurrence and survival status until the end of the study, and then assigned patients into the recurrent or the non-recurrent group. The tumor recurrence rate was 52.2% during the median follow-up period of 3.0 years. Patients had significantly lower plasma malondialdehyde level, but significantly or slightly higher levels of GSH, glutathione disulfide, trolox equivalent antioxidant capacity, glutathione peroxidase (GPx), and glutathione reductase (GR) activities after tumor resection compared to the respective levels before tumor resection in both recurrent and non-recurrent groups. GSH level in HCC tissue was significantly higher than that in adjacent normal tissue in both recurrent and non-recurrent patients. Decreased plasma GPx (HR = 0.995, p = 0.01) and GR (HR = 0.98, p = 0.04) activities before tumor resection, and the increased change of GPx (post-pre-resection) (HR = 1.004, p = 0.03) activity were significantly associated with the recurrence of HCC. These findings suggest there might be a possible application of GPx or GR as therapeutic targets for reducing HCC recurrence.

Intermediate Cu(II)-Thiolate Species in the Reduction of Cu(II)GHK by Glutathione: A Handy Chelate for Biological Cu(II) Reduction.

Gly-His-Lys (GHK) is a tripeptide present in the human bloodstream that exhibits a number of biological functions. Its activity is attributed to the copper-complexed form, Cu(II)GHK. Little is known, however, about the molecular aspects of the mechanism of its action. Here, we examined the reaction of Cu(II)GHK with reduced glutathione (GSH), which is the strongest reductant naturally occurring in human plasma. Spectroscopic techniques (UV-vis, CD, EPR, and NMR) and cyclic voltammetry helped unravel the reaction mechanism. The impact of temperature, GSH concentration, oxygen access, and the presence of ternary ligands on the reaction were explored. The transient GSH-Cu(II)GHK complex was found to be an important reaction intermediate. The kinetic and redox properties of this complex, including tuning of the reduction rate by ternary ligands, suggest that it may provide a missing link in copper trafficking as a precursor of Cu(I) ions, for example, for their acquisition by the CTR1 cellular copper transporter.

Nanoscale Covalent Organic Frameworks with Donor-Acceptor Structures as Highly Efficient Light-Responsive Oxidase-like Mimics for Colorimetric Detection of Glutathione.

Although organic artificial enzymes have been reported as biomimetic oxidation catalysts and are widely used for colorimetric biosensors, developing organic artificial enzymes with high enzymatic activity is still a challenge. Two-dimensional (2D) covalent organic frameworks (COFs) have shown superior potential in biocatalysts because of their periodic π-π arrays, tunable pore size and structure, large surface area, and thermal stability. The interconnection of electron acceptor and donor building blocks in the 2D conjugated COF skeleton can lead to narrower band gaps and efficient charge separation and transportation and thus is helpful to improve catalytic activity. Herein, a donor-acceptor 2D COF was synthesized using tetrakis(4-aminophenyl)pyrene (Py) as an electron donor and thieno[3,2-b]thiophene-2,5-dicarbaldehyde (TT) as an electron acceptor. Under visible light irradiation, the donor-acceptor 2D COF exhibited superior enzymatic catalytic activity, which could catalyze the oxidation of chromogenic substrates such as 3,3',5,5'-tetramethylbenzidine (TMB) by the formation of superoxide radicals and holes. Based on the above property, the photoactivated donor-acceptor 2D COF with enzyme-like catalytic properties was designed as a robust colorimetric probe for cheap, highly sensitive, and rapid colorimetric detection of glutathione (GSH); the corresponding linear range of GSH was 0.4-60 µM, and the limit of detection was 0.225 µM. This study not only presents the construction of COF-based light-activated nanozymes for environmentally friendly colorimetric detection of GSH but also provides a smart strategy for improving nanozyme activity.

Evaluation of Silver Nanoparticles Caffeic Acid Complex Compound as New Potential Therapeutic Agent against Cancer Incidence in Mice.

OBJECTIVE: The present work was designed to study the effect of new conjugated caffeic and folic acid with silver nanoparticles with definite molecular size applied with and without gamma radiation exposure, as an antitumor agent against experimentally induced Ehrlich tumor and attempted to identify their potential molecular mechanisms of action throughout determination of anti-tumor activities using MTT cytotoxic assay against two human carcinoma cell lines in vitro, such as apoptosis analysis by flow cytometry through caspase-8, caspase-3 and TNF determination in vivo. MATERIALS AND METHODS: Adult female albino mice were used and divided into five groups. Animals were sacrificed and the following parameters were estimated, glutathione (GSH), glutathione peroxidase (GPx), superoxide dismutase (SOD) in blood in addition to caspase8, caspase 3 and tumor necrosis factor (TNF) of tumor tissue, liver and kidney function also measured in plasma. The tumor specimens were processed for histopathological examination. RESULTS: Nano-silver folate caffeic (NSFC) complex compound treatment resulted in growth inhibition in Ehrlich solid tumor, Hep-G2, and MCF-7 cells (IC50 0.062 mg, 7.70 µM, and 14.50 µM, respectively). Flow cytometric analysis revealed that (NSFC) with radiation IR had apoptotic effects at caspases 8 (Mean±SD) (49.4±14), caspase3 (39.97±9.75), and TNF (40.1±3.4) more than any other groups. Those disturbances were found to be associated with a kinetic induction of apoptosis and showed modulation of the antioxidant system {glutathione (GSH), glutathione peroxidase (GPx) and superoxide dismutase (SOD) which were 60.70±0.80, 26.73±0.80, 39.52±0.58 respectively}at the group which took (NSFC+IR), besides its high percentage of necrotic cells by histopathological studies. In conclusion, the present study showed that the treatment of (NSFC) exhibits very efficient oncolytic activity in delaying tumor growth in mice bearing Ehrlich Solid Carcinoma (ESC) and the mechanisms underlying the inhibitory effect of the present compound involve both an apoptotic effect against Hep-G2 and MCF-7 cells and modulation of antioxidant system.

An ultrasensitive chemiluminescent biosensor for tracing glutathione in human serum using BSA@AuNCs as a peroxidase-mimetic nanozyme on a luminol/artesunate system.

In this work, a nanosensor chemiluminescent (CL) probe for sensing glutathione (GSH) was developed, for the first time, based on its inhibition of the intrinsic peroxidase-mimetic effect of BSA@AuNCs. The endoperoxide linkage of artesunate could be hydrolyzed by BSA@AuNCs resulting in the release of reactive oxygen species (ROS), and the consequent generation of strong CL emission. By virtue of the strong covalent interactions of -S⋯Au-, GSH could greatly suppress the peroxidase-mimetic effect of BSA@AuNCs, leading to a drastic CL quenching. The CL quenching efficiency increased proportionally to the logarithm of GSH concentration through the linearity range of 50.0-5000.0 nM with a limit of detection of 5.2 nM. This CL-based strategy for GSH tracing demonstrated the advantages of ultrasensitivity, high selectivity and simplicity. This strategy was successfully utilized to measure GSH levels in human serum with reasonable recovery results of 98.71%, 103.18%, and 101.68%, suggesting that this turn-off CL sensor is a promising candidate for GSH in biological and clinical samples.

Estrogen Replacement Therapy Induces Antioxidant and Longevity-Related Genes in Women after Medically Induced Menopause.

Females live longer than males in many species, including humans, and estrogens are in part responsible for this protection against aging. We reported previously that estrogens can protect rats against oxidative stress, by inducing antioxidant and longevity-related genes. Thus, this study was aimed at confirming the ability of estrogens to upregulate antioxidant and longevity-related genes in humans. For this purpose, we selected 16 women of reproductive age (18-42 years old) undergoing a fertility treatment that includes a medically induced menopause, at the Valencian Infertility Institute. We took blood samples at each time point of the treatment (basal, induced menopause, estrogen, and estrogen plus progesterone replacement therapy). mRNA expression of antioxidant and longevity-related genes in peripheral blood mononuclear cells (PBMC) was determined by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Determination of reduced glutathione (GSH) in total blood was carried out using high-performance liquid chromatography (HPLC). As expected, we found that medically induced menopause significantly decreased sexual hormone (estrogens and progesterone) levels. It also lowered glutathione peroxidase (GPx), 16S rRNA, P21, and TERF2 mRNA expression and blood GSH levels. Estrogen replacement therapy significantly restored estrogen levels and induced mRNA expression of manganese superoxide dismutase (MnSOD), GPx, 16S rRNA, P53, P21, and TERF2 and restored blood GSH levels. Progesterone replacement therapy induced a significant increase in MnSOD, P53, sestrin 2 (SENS2), and TERF2 mRNA expression when compared to basal conditions. These findings provide evidence for estrogen beneficial effects in upregulating antioxidant and longevity-related genes in women.

Enzymatic Changes in Red Blood Cells of Diamond-Blackfan Anemia.

Diamond-Blackfan anemia is a congenital bone marrow failure syndrome characterized by red blood cell (RBC) aplasia with varied malformations in infants. Elevated activity of adenosine deaminase (ADA) has been considered as a useful biomarker of Diamond-Blackfan anemia, and ADA assay has been shown to be more sensitive than genetic diagnosis. Approximately, 80% of the examined patients showed elevated ADA activity, whereas genetic tests of ribosome subunit genes identified mutations in approximately 60% of the patients. We previously reported that reduced glutathione (GSH) levels in RBCs may serve as a biomarker of Diamond-Blackfan anemia. In this study, to confirm the universality of our data, we extended the analysis to seven RBC enzymes and GSH of 14 patients with Diamond-Blackfan anemia and performed a cross-analysis study using enzyme activity assay and recently reported proteome data. Statistical analysis revealed that both data exhibited high similarity, upregulation in the hexokinase and pentose-phosphate pathway, and downregulation in glycolytic enzymes such as phosphofructokinase and pyruvate kinase, in the RBCs obtained from the subjects with Diamond-Blackfan anemia. The only discrepancy between enzyme activity and proteome data was observed in glucose-6-phosphate dehydrogenase (G6PD), as increased G6PD activity showed no relation with the significant elevation in protein levels. These results suggest that our enzymatic activity data of Diamond-Blackfan anemia are universal and that the enzymatic activation of G6PD via a hitherto-unveiled mechanism is another metabolic feature of RBCs of Diamond-Blackfan anemia.