Biomarkers Of Protein Oxidation Research Articles

Effect of fish oil supplementation on histological changes, apoptosis and oxidative stress of rat placenta against formaldehyde-induced toxicity

Formaldehyde (FA) as a common organic compound has been shown to cause placental dysfunction and fetal defects. The potential benefits of fish oil (FOil) in protecting placental structures are attributed to its antioxidant properties. This study aimed to explore the preventive role of FOil in mitigating the adverse effects of FA in pregnant rats. Thirty pregnant Wistar rats were randomly categorized into five groups of control, sham (Normal saline; Orally and intraperitoneally), FOil (0.5 ml/day; Orally), FA (5 mg/kg/bw; intraperitoneally), FA+FOil. The treatment period was from day 0–20 of pregnancy. On the 20th day of pregnancy, placental morphometric parameters were measured. The histological and histochemical analyses were performed using H&E and PAS staining, respectively. Also, the placenta tissue was analyzed for oxidative stress biomarkers, p-53 protein levels, and the expression of caspase-3 gene. The administration of FA led to a significant decrease in the weight, diameter, and thickness of the placenta, as well as a decrease in the thickness of the decidua layer, junctional and labyrinth zone, and the number of trophoblast giant cells in rat placentas. FA led to a significant increase in placental p-53 protein levels, caspase-3 expression, and oxidative stress biomarkers. Administration of FOil to pregnant rats treated with FA led to a significant decrease in morphometric and histological changes, oxidative stress, and the expression of genes associated with apoptosis. The findings suggest that the administration of FOil to FA-treated pregnant rats can protect placental histopathological changes by enhancing the activity of the antioxidant enzymes.

MARKERS OF LIPID AND PROTEIN OXIDATION IN THE BLOOD OF WOMEN AND MEN WITH AUTOIMMUNE HASHIMOTO'S THYROIDITIS

Purpose: The aim of this study was to analyze changes in markers of oxidative stress (lipid peroxidation and oxidative modification of proteins) and the total antioxidant activity in the blood of women and men with autoimmune Hashimoto's thyroiditis (HT). Methodology. This study was carried out in a group of 153 individuals. The group of women participating in the study consisted of 109 individuals (71.24%), while the group of men consisted of 44 individuals (28.76%). All persons were divided into two groups: 1) euthyroidism (n = 64; men – n = 18, and women – n = 46); and 2) Hashimoto's autoimmune thyroiditis with subclinical hypothyroidism (n = 89; men – n = 26, and women – n = 63). The functioning of the thyroid gland was additionally verified by measuring the concentration of thyrotropin (TSH), free triiodothyronine (fT3), free tetraiodothyronine (thyroxine, fT4), and antibodies against thyroid peroxidase (anti-TPO). The concentration of thyrotropin, triiodothyronine, free thyroxine and the concentration of antibodies against thyroperoxidase in human serum were determined using the electrochemiluminescence method "ECLIA" on the immunological analyzer Elecsys Cobas e 411 (Hitachi, Japan). In each group of women and men with euthyroidism and Hashimoto's autoimmune thyroiditis with subclinical hypothyroidism, the 2-thiobarbituric acid reactive substances (TBARS), carbonyl derivatives of protein oxidative modification (OMP), and total antioxidant capacity (TAC) were determined. Scientific novelty. Statistically significant changes in levels of oxidative stress markers were not observed. In women with HT, elevated TBARS levels with simultaneously increased TAC levels in the plasma and erythrocytes were observed. Additionally, levels of aldehydic and ketonic derivatives of oxidative modification of proteins in the blood of women with HT were lower compared to the women with the euthyroid state. In men with HT, levels of markers of oxidative stress (except TAC levels in the plasma) were lower compared to those obtained in men with the euthyroid state. Conclusions. Hashimoto's thyroiditis with subclinical hypothyroidism does not have a direct influence on levels of biomarkers of lipid and protein oxidation. The results obtained in the current study highlight the need for future investigations of biomarkers of lipid and protein oxidation, especially depending on the duration of this disease.

Validation of plasma protein glycation and oxidation biomarkers for the diagnosis of autism

Autism Spectrum Disorder (ASD) is a common neurodevelopmental disorder in children. It is currently diagnosed by behaviour-based assessments made by observation and interview. In 2018 we reported a discovery study of a blood biomarker diagnostic test for ASD based on a combination of four plasma protein glycation and oxidation adducts. The test had 88% accuracy in children 5–12 years old. Herein, we present an international multicenter clinical validation study (N = 478) with application of similar biomarkers to a wider age range of 1.5–12 years old children. Three hundred and eleven children with ASD (247 male, 64 female; age 5.2 ± 3.0 years) and 167 children with typical development (94 male, 73 female; 4.9 ± 2.4 years) were recruited for this study at Sidra Medicine and Hamad Medical Corporation hospitals, Qatar, and Hospital Regional Universitario de Málaga, Spain. For subjects 5–12 years old, the diagnostic algorithm with features, advanced glycation endproducts (AGEs)—Nε-carboxymethyl-lysine (CML), Nω-carboxymethylarginine (CMA) and 3-deoxyglucosone-derived hydroimidazolone (3DG-H), and oxidative damage marker, o,o’-dityrosine (DT), age and gender had accuracy 83% (CI 79 – 89%), sensitivity 94% (CI 90–98%), specificity 67% (CI 57–76%) and area-under-the-curve of receiver operating characteristic plot (AUROC) 0.87 (CI 0.84–0.90). Inclusion of additional plasma protein glycation and oxidation adducts increased the specificity to 74%. An algorithm with 12 plasma protein glycation and oxidation adduct features was optimum for children of 1.5–12 years old: accuracy 74% (CI 70–79%), sensitivity 75% (CI 63–87%), specificity 74% (CI 58–90%) and AUROC 0.79 (CI 0.74–0.84). We conclude that ASD diagnosis may be supported using an algorithm with features of plasma protein CML, CMA, 3DG-H and DT in 5–12 years-old children, and an algorithm with additional features applicable for ASD screening in younger children. ASD severity, as assessed by ADOS-2 score, correlated positively with plasma protein glycation adducts derived from methylglyoxal, hydroimidazolone MG-H1 and Nε(1-carboxyethyl)lysine (CEL). The successful validation herein may indicate that the algorithm modifiable features are mechanistic risk markers linking ASD to increased lipid peroxidation, neuronal plasticity and proteotoxic stress.

Mechanism-Based Targeting of Sickle Cell Pathobiology and Pain with Novel Transdermal Curcumin

Pain is a debilitating consequence of sickle cell disease (SCD). We examined the potential of novel topical transdermal curcumin (TDC) gel with transdermal systemic delivery to target pain and SCD pathobiology. Curcumin is an antioxidant and anti-inflammatory polyphenol with therapeutic potential but has poor oral bioavailability. TDC gel (Vasceptor TM, Vascarta Inc.), containing 0.1 M of curcuminoids (derived from Curcugen, Dolcas-Biotech, LLC), or vehicle were applied (0.1 mL) topically by gentle rubbing to the abdomen on alternating days for 3 weeks followed by analysis of blood, organ pathology and skin secretome. Using high-performance liquid chromatography, we found that curcumin levels peaked in the plasma (7.87 µg/mL) and blood cells (6.78 µg/mL) 60 min following administration in C57BL/6 mice, thus, showing efficient bioavailability. Next, we used humanized ‘ sickle‘, homozygous transgenic mice ( HbSS-BERK) expressing >99% human sickle hemoglobin (HbSS) without mouse α- and β-globins. These mice mimic the pathobiology and features of pain observed in persons with SCD. We observed that TDC application in male and female HbSS led to a significant decrease in hyperalgesia over the 21 days (D) of treatment. Mechanical hyperalgesia significantly decreased after 14D of treatment in males and after 21D in females (p<.05 and p<.01, respectively Vs. BL). Similarly, cold hyperalgesia (paw withdrawal frequency on cold plate at 4˚C) decreased significantly in males after 24 hours and in females after 7D of TDC treatment (p<.05 and .01, respectively Vs. BL). Non-evoked cold avoidance showed that males spent significantly more time in the colder chamber at 23ºC on 14D, and females did so on 21D after TDC treatment (p<.001 & p<.01, respectively Vs. BL). Throughout 21D TDC treatment, females showed significantly lower analgesic response in cold hyperalgesia compared to male HbSS, similar to relatively poor response to analgesia in female Vs. male individuals with SCD. The amelioration of hyperalgesia for 21D with TDC suggests a disease-modifying effect. Indeed, we observed a significant increase in hematocrit (p<.05), a reduction in reticulocytes (p<.05), and an appreciable increase (43.2%) in Hb and decreased lactate dehydrogenase activity in the blood of TDC-treated HbSS mice Vs. vehicle (p<.01). RBCs from TDC treated HbSS mice showed enhanced ATP levels (p <.01) and reduced protein carbonylation, both biomarkers of protein oxidation (p<.045) Vs RBCs from vehicle-treated HbSS. Histopathology showed a significant reduction in vascular congestion and iron deposits in TDC-treated male HbSS compared to vehicle in the spleen (p<.0003 & p<.001, respectively) and in % fields involved in hepatic infarcts and iron deposits (p<.02 & p<.044, respectively). Together, decreased hemolysis, increased Hb, hematocrit, and ATP suggest RBC stabilization, improved mitochondrial metabolism, and reduced oxidative stress and organ damage, leading to a disease-modifying effect of TDC. TDC also significantly reduced global inflammatory marker serum amyloid-P (p<.05) and inflammatory cytokines in the skin secretome with a concomitant reduction in interleukins [2 (p<.05), 4 (p<.01), and 6 (p<.01)], monocyte chemoattractant protein 1 (MCP-1; p<.01), interferon-gamma (IFN-γ; p<.05), granulocyte macrophage-colony stimulating factor (GM-CSF; p<.01), and regulated on activation, normal T-cell expressed and secreted protein (RANTES; p<.05) compared to vehicle. MCP-1 contributes to neuropathic pain and inflammation; GM-CSF stimulates granulocyte differentiation and growth. Both RANTES and MCP-1 may also activate mast cells. TDC led to a significant decrease in cutaneous mast cell degranulation (p<.001) Vs. vehicle in sickle mice. These data strongly suggest an anti-inflammatory effect of TDCby targeting the release of cytokines and inhibiting granulocyte activity. TDC significantly ameliorates hyperalgesia (chronic pain), inflammation, hemolysis, oxidative stress, and organ damage and improves mitochondrial function and hematological parameters of SCD pathobiology, indicative of disease modifying and anti-nociceptive effects. The results suggest if started early in life, the use of an easy-to-deploy novel TDC formulation, with increased bioavailability and non-toxic properties that directly target sickle cell pathobiology, may prevent chronic pain in SCD.

Preliminary evaluation of the antiglycoxidant activity of verapamil using various in vitro and in silico biochemical/biophysical methods

Introduction: Glycoxidative stress is essential for linking glucose disturbances and cardiovascular diseases. Unfortunately, contemporary antidiabetic drugs do not have an antiglycative effect but only lower blood glucose levels. Therefore, there is an intense search for substances that could inhibit protein glycation and prevent diabetic complications. A potential antioxidant activity has been demonstrated with verapamil, a phenylalkylamine derivative belonging to selective calcium channel blockers. Verapamil has a well-established position in cardiology due to its wide range of indications and good safety profile. Nevertheless, the antidiabetic activity of verapamil is still unclear. We are the first to comprehensively evaluate the verapamil’s effect on protein glycoxidation using various in vitro and in silico models.Methods: Bovine serum albumin (BSA) was used to assess the rate of glycoxidation inhibition by verapamil. As glycating factors, sugars (glucose, fructose, and ribose) and aldehyde (glyoxal) were used. Chloramine T was used as an oxidizing agent. Aminoguanidine (protein glycation inhibitor) and Trolox (antioxidant) were used as control substances. The biomarkers of oxidation (total thiols, protein carbonyls, advanced oxidation protein products), glycation (Amadori products, β-amyloid, advanced glycation end products [AGEs]), and glycoxidation (tryptophan, kynurenine, N-formylkynurenine, dityrosine) were evaluated using colorimetric and fluorimetric methods. The mechanism of antiglycative activity of verapamil was assessed using in silico docking to study its interaction with BSA, glycosidases, and seventeen AGE pathway proteins.Results: In all in vitro models, biomarkers of protein glycation, oxidation, and glycoxidation were significantly ameliorated under the influence of verapamil. The glycoxidation inhibition rate by verapamil is comparable to that of potent antiglycating agents and antioxidants. The molecular docking simulations showed that verapamil bound preferentially to amino acids prone to glycoxidative damage out of an α-glucosidase’s active center. Among all AGE pathway proteins, verapamil was best docked with the Janus kinase 2 (JAK2) and nuclear factor-κB (NF-κB).Discussion: The results of our study confirm the antiglycoxidant properties of verapamil. The drug’s action is comparable to recognized substances protecting against oxidative and glycation modifications. Verapamil may be particularly helpful in patients with cardiovascular disease and concomitant diabetes. Studies in animal models and humans are needed to confirm verapamil’s antiglycative/antidiabetic activity.

Molecular and biochemical biomarkers in the American oyster Crassostrea virginica exposed to herbicide Roundup® at high temperature.

Aquatic organisms are frequently exposed to various environmental stressors. Thus, the effects of high temperatures and herbicides on aquatic organisms are a major subject of interest. In this study, we studied the effects of short-term exposure (1week) to Roundup®, a glyphosate-based herbicide (concentrations: 0.5 and 5µg/L), on the morphology of gills, digestive glands, and connective tissues, and the expression of heat shock protein-70 (HSP70, a chaperone protein), cytochrome P450 (CYP450, a biomarker of environmental contaminants), dinitrophenyl protein (DNP, a biomarker of protein oxidation), nitrotyrosine protein (NTP, a biomarker of protein nitration), antioxidant enzymes such as superoxidase dismutase (SOD) and catalase (CAT) in tissues of American oyster, Crassostrea virginica (Gmelin, 1791) maintained at high temperature (30°C). Histological analyses showed an increase in mucous production in the gills and digestive glands, and in hemocyte aggregation in the connective tissues as well as a structural change of lumen in the digestive glands of oysters exposed to Roundup. Immunohistochemical and quantitative RT-PCR analyses showed significant (P < 0.05) increases in HSP70, CYP450, DNP, NTP, CAT, and SOD mRNA and protein expressions in the tissues of oysters exposed to Roundup. Taken together, these results suggest that exposure to Roundup at high temperature induces overproduction of reactive oxygen species/reactive nitrogen species which in turn leads to altered prooxidant-antioxidant activity in oyster tissues. Moreover, our results provide new information on protein oxidation/nitration and antioxidant-dependent mechanisms for HSP70 and CYP450 regulations in oysters exposed to Roundup at high temperature.

Hypoxemia events in preterm neonates are associated with urine oxidative biomarkers.

Intermittent hypoxemia (IH) events are common in preterm neonates and are associated with adverse outcomes. Animal IH models can induce oxidative stress. We hypothesized that an association exists between IH and elevated peroxidation products in preterm neonates. Time in hypoxemia, frequency of IH, and duration of IH events were assessed from a prospective cohort of 170 neonates (<31 weeks gestation). Urine was collected at 1 week and 1 month. Samples were analyzed for lipid, protein, and DNA oxidation biomarkers. At 1 week, adjusted multiple quantile regression showed positive associations between several hypoxemia parameters with various individual quantiles of isofurans, neurofurans, dihomo-isoprostanes, dihomo-isofurans, and ortho-tyrosine and a negative correlation with dihomo-isoprostanes and meta-tyrosine. At 1 month, positive associations were found between several hypoxemia parameters with quantiles of isoprostanes, dihomo-isoprostanes and dihomo-isofurans and a negative correlation with isoprostanes, isofurans, neuroprostanes, and meta-tyrosine. Preterm neonates experience oxidative damage to lipids, proteins, and DNA that can be analyzed from urine samples. Our single-center data suggest that specific markers of oxidative stress may be related to IH exposure. Future studies are needed to better understand mechanisms and relationships to morbidities of prematurity. Hypoxemia events are frequent in preterm infants and are associated with poor outcomes. The mechanisms by which hypoxemia events result in adverse neural and respiratory outcomes may include oxidative stress to lipids, proteins, and DNA. This study begins to explore associations between hypoxemia parameters and products of oxidative stress in preterm infants. Oxidative stress biomarkers may assist in identifying high-risk neonates.

Oxime blot: A novel method for reliable and sensitive detection of carbonylated proteins in diverse biological systems

Oxidative stress and oxidative protein damage occur in various biological processes and diseases. The carbonyl group on amino acid side chains is the most widely used protein oxidation biomarker. Carbonyl groups are commonly detected indirectly through their reaction with 2,4-dinitrophenylhydrazine (DNPH) and subsequent labeling with an anti-DNP antibody. However, the DNPH immunoblotting method lacks protocol standardization, exhibits technical bias, and has low reliability. To overcome these shortcomings, we have developed a new blotting method in which the carbonyl group reacts with the biotin-aminooxy probe to form a chemically stable oxime bond. The reaction speed and the extent of the carbonyl group derivatization are increased by adding a p-phenylenediamine (pPDA) catalyst under neutral pH conditions. These improvements are crucial since they ensure that the carbonyl derivatization reaction reaches a plateau within hours and increases the sensitivity and robustness of protein carbonyl detection. Furthermore, derivatization under pH-neutral conditions facilitates a good SDS-PAGE protein migration pattern, avoids protein loss by acidic precipitation, and is directly compatible with protein immunoprecipitation. This work describes the new Oxime blot method and demonstrates its use in detecting protein carbonylation in complex matrices from diverse biological samples.

Prenatal oxidative stress and rapid infant weight gain.

Infant weight patterns predict subsequent weight outcomes. Rapid infant weight gain, defined as a >0.67 increase in weight-for-age z-score (WAZ) between two time points in infancy, increases obesity risk. Higher oxidative stress, an imbalance between antioxidants and reactive oxygen species, has been associated with low birthweight and paradoxically also with later obesity. We hypothesized that prenatal oxidative stress may also be associated with rapid infant weight gain, an early weight pattern associated with future obesity. Within the NYU Children's Health and Environment Study prospective pregnancy cohort, we analyzed associations between prenatal lipid, protein, and DNA urinary oxidative stress biomarkers and infant weight data. Primary outcome was rapid infant weight gain (>0.67 increase in WAZ) between birth and later infancy at the 8 or 12 month visit. Secondary outcomes included: very rapid weight gain (>1.34 increase in WAZ), low (<2500 g) or high (≥4000 g) birthweight, and low (< -1 WAZ) or high (>1 WAZ) 12 month weight. Pregnant participants consented to the postnatal study (n = 541); 425 participants had weight data both at birth and in later infancy. In an adjusted binary model, prenatal 8-iso-PGF2α, a lipid oxidative stress biomarker, was associated with rapid infant weight gain (aOR 1.44; 95% CI: 1.16, 1.78, p = 0.001). In a multinomial model using ≤0.67 change in WAZ as a reference group, 8-iso-PGF2α was associated with rapid infant weight gain (defined as >0.67 but ≤1.34 WAZ; aOR 1.57, 95% CI: 1.19, 2.05, p = 0.001) and very rapid infant weight gain (defined as >1.34 WAZ; aOR 1.33; 95% CI: 1.02, 1.72, p < 0.05) Secondary analyses detected associations between 8-iso-PGF2α and low birthweight outcomes. We found an association between 8-iso-PGF2α, a lipid prenatal oxidative stress biomarker, and rapid infant weight gain, expanding our understanding of the developmental origins of obesity and cardiometabolic disease.

High Concentration of Protein Oxidation Biomarker O-Tyr/Phe Predicts Better Outcome in Childhood Bacterial Meningitis.

Neuronal damage in bacterial meningitis (BM) partly stems from the host´s inflammatory response and induced oxidative stress (OS). We studied the association of cerebrospinal fluid (CSF) biomarkers indicating oxidative damage to proteins with course of illness and outcome in childhood BM in Angola. Ortho-tyrosine/phenylalanine (o-Tyr/Phe), 3-chlorotyrosine/para-tyrosine (3Cl-Tyr/p-Tyr), and 3-nitrotyrosine/para-tyrosine (3NO2-Tyr/p-Tyr) concentration ratios were measured in 79 BM admission CSF samples, employing liquid chromatography coupled to tandem mass spectrometry. Besides death, disease outcomes were registered on Day 7 of treatment and one month after discharge (control visit). The outcome was graded according to the modified Glasgow Outcome Scale (GOS), which considers neurological and audiological sequelae. Children with a o-Tyr/Phe ratio below the median were more likely to present focal convulsions and secondary fever during recovery and suboptimal outcome (GOS < 5) on Day 7 and at control visit (odds ratio (OR) 2.85; 95% CI 1.14-7.14 and OR 5.23; 95% CI 1.66-16.52, respectively). Their most common sequela was ataxia on Day 7 and at control visit (OR 8.55; 95% CI 2.27-32.22 and OR 5.83; 95% CI 1.12-30.4, respectively). The association of a higher admission CSF o-Tyr/Phe ratio with a better course and outcome for pediatric BM points to a beneficial effect of OS.

Oxidative stress biomarkers in dogs with benign prostatic hyperplasia

BackgroundThe aim of this study was to evaluate total antioxidant capacity (TAC) and biomarkers of lipid and protein peroxidation in the blood serum of dogs with benign prostatic hyperplasia (BPH). The study was conducted on 36 intact male dogs of various breeds. The dogs were assigned to two groups: BPH group (n = 18) and non-affected group (n = 18). Blood samples were collected from the cephalic vein. The antioxidant status of the serum was assessed using TAC. The levels of bityrosine, formylkynurenine and SH-groups were used as protein peroxidation biomarkers and the level of radical cations of N,N-diethyl-paraphenylene diamine (RC-DEPPD) was used as a marker for lipid peroxidation. TAC and the concentrations of SH-groups and RC-DEPPD in the serum were determined spectrophotometrically, the concentrations of bityrosine and formylokynurenine, were determined using spectrofluorimetric methods.ResultsThe mean value of TAC in the serum was significantly lower (P = 0.01) in BPH dogs than in non-affected dogs (3.10 ± 0.56 vs 4.20 ± 1.60 μmol/g protein). Mean levels of protein and lipid oxidation biomarkers showed a trend towards oxidative imbalance, but there were no statistically significant differences between dogs with BPH and controls (P > 0.05).ConclusionIn conclusion, significantly lower serum TAC in dogs with BPH compared to non-affected dogs suggests a potential involvement of oxidative stress in the pathogenesis of BPH in dogs. More studies are needed to clarify the role of oxidative stress in the development of BPH in dogs.

Dose-Dependent Alterations in the Biomarkers of Lipid and Protein Oxidation in the Blood of Patients with Type 2 Diabetes Mellitus after in vitro Incubation with Extracts of Chelidonium majus L.

The role of oxidative stress in the occurrence and development of diabetes mellitus is both critical and pivotal. Several molecular event cascades in different metabolic pathways such as glycolytic, hexosamine, protein kinase C, polyol and advanced glycation end-product pathways have been identified as pro-oxidative processes and are usually upregulated in diabetics. Consistent with our previous studies, we continue to evaluate the antioxidant potential of great celandine (Chelidonium majus L., CM), a representative of the Papaveraceae family, collected from northern parts of Poland using the blood samples of patients with type 2 diabetes mellitus. Therefore, in the present study, oxidative stress biomarkers (2-thiobarbituric acid reactive substances (TBARS), aldehydic and ketonic derivatives of oxidative modification of proteins (OMP)) were used to evaluate the antioxidant properties of the stalk and root extracts of CM in final doses of 5 mg.mL-1, 2.5 mg.mL-1, 1.25 mg.mL-1 and 0.63 mg.mL-1. Plant materials were collected from natural habitats on the territory of the Kartuzy district in the Pomeranian province (northern part of Poland). The use of extracts derived from both roots and stalks of CM collected from both urban and rural agglomerations in final doses of 5 mg.mL-1, 2.5 mg.mL-1, and 1.25 mg.mL-1 resulted in a significant enhancement of lipid peroxidation in the blood samples. On the contrary, only incubation of blood samples with stalk extracts of CM collected from urban areas at a final dose of 0.63 mg.mL-1 resulted in a no-significant decrease in TBARS levels contributing to the protection of lipid structures in membranes. Similar results were obtained by analyzing levels of aldehydic derivatives of oxidatively modified proteins in the blood samples after in vitro incubation with the extracts, where final doses of 5 mg.mL-1, 2.5 mg.mL-1, and 1.25 mg.mL-1 significantly increased the oxidation process in protein structures. Analysis of levels of ketonic derivatives of oxidatively modified proteins showed that the use of root extracts of CM collected from urban agglomerations in final doses of 2.5 and 1.25 mg.mL-1 reduced levels of oxidatively modified proteins, while the use of stalk extracts of CM harvested from urban agglomerations in a final dose of 0.63 mg.mL-1 statistically significantly reduced levels of ketonic derivatives of oxidatively modified proteins compared to the control samples. These in vitro studies indicate that extracts derived from this plant are a significant source of natural metabolites that could be cytotoxic in final doses of 5 mg.mL-1, 2.5 mg.mL-1, and 1.25 mg.mL-1 to the blood of patients with T2DM. Only a final dose of 0.63 mg.mL-1 no significantly changed levels of lipid and protein oxidation in the blood samples.

Effects of dietary yeast β-1.3/1.6-glucans on oxidative stress biomarkers in hearts and livers of rainbow trout (Oncorhynchus mykiss Walbaum), European whitefish (Coregonus lavaretus L.), and grayling (Thymallus thymallus L.)

Abstract The present study was performed to investigate the effects of dietary yeast β-1,3/1,6-D-glucans supplemented over a 14-day feeding period on liver and cardiac function and the oxidative mechanism underlying these effects. We assessed relevant lipid peroxidation and protein oxidation biomarkers, antioxidant defense indices [superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx), total antioxidant capacity (TAC)], and biochemical alterations [activities of aminotransferases (AT), lactate dehydrogenase (LDH), and succinate dehydrogenase (SDH), and levels of lactate (L) and pyruvate (P)] in rainbow trout, European whitefish, and grayling. The fish received a control diet and an experimental diet containing yeast β-1,3/1,6-D-glucans at a dose of 1% in the basal feed for 14 days. The results demonstrated enhancement in the phagocytic activity and phagocytic index in the groups fed β-glucans, compared to the control groups. In the groups fed β-glucans, the oxidative stress parameters such as lipid peroxidation, oxidatively modified proteins, and TAC did not vary significantly. The dietary β-glucans stimulated CAT and GPx activities in hepatic and cardiac tissues in comparison to the control group; however, a reverse trend was observed in the GR activity in these tissues.

Insights into the characteristics and molecular transformation of lipids in Litopenaeus vannamei during drying from combined lipidomics

Hot-air drying is one of the most important processing methods for aquatic products; however, this technique usually induces protein and lipid oxidation. Although an association was found between protein and lipid oxidation, the effects of drying on lipid profiles and their correlation with lipid and protein oxidation in shrimps remain unclear. Herein, the lipid oxidation and the myofibrillar protein oxidation in shrimp (Litopenaeus vannamei) during drying were investigated by assessing the peroxide value (POV) and thiobarbituric acid-reactive substances value (TBARS), carbonyl content, total sulfhydryl amount, and surface hydrophobicity. Ultra-performance liquid chromatography-tandem mass spectrometry-mass spectrometry-based lipidomics was applied to analyze the effect of drying time (0 and 16 h) on the lipidomics of L. vannamei. Among the 31 lipid subclasses that were examined, phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), diglycerides (DGs), and triglycerides (TGs) accounted for the vast majority of peak areas. High relative content of unsaturated fatty acids, specifically oleic acid, linoleic acid, docosahexaenoic acid, and arachidonic acid, were localized mainly at sn-2 and sn-3 lipid positions. Thirty-nine significantly (p < 0.01) different lipid molecular species (31 of which belong to PC, PE, DG, and TG) were selected as the potential biomarkers of protein and lipid oxidation. The results indicated that drying affects the lipidomic profile, protein oxidation and lipid oxidation of L. vannamei.

Electrochemical behavior of protein oxidation biomarkers meta-, ortho- and 3-chloro-tyrosine on carbon electrodes: A comparative study with para-tyrosine and phenylalanine

The anodic behavior of the isomers meta-, ortho- and para-tyrosine (m-, o-, p-Tyr) and of phenylalanine in aqueous support electrolytes, with different pH values, on the glassy carbon electrode (GCE), were investigated and compared using cyclic and differential pulse voltammetry. The electrochemical behavior of 3‑chloro-tyrosine (3-Cl-Tyr) in different aqueous media was also investigated on a GCE and boron-doped diamond electrode (BDDE). The results showed that all tyrosines undergo oxidation at the phenolic group, with the removal of one electron and one proton, forming one intermediate radical, Tyr●. The reactivity of this radical in aqueous medium, however, is clearly conditioned by its position in the tyrosine structure. The m-Tyr● reaction occurs with the formation of polymers and with water to form one quinone derivative. The o-Tyr● radical reacts preferentially with water leading to formation of two electroactive quinone derivatives and p-Tyr● preferentially follows the polymerization. The electrochemical results of the 3-Cl-Tyr electro-oxidation were very similar in relation to p-Tyr. There was little influence of the substituent -Cl, occurring in the phenolic group with predominantly polymer formation. On the other hand, unlike the other tyrosines, one irreversible and pH-dependent cathodic peak for 3-Cl-Tyr was detected, associated to the electro-reduction of the chloro group attached at C3. Using differential pulse voltammetry (DPV), experimental optimizations were also performed for quantification of 3-Cl-Tyr with low detection limit. These were carried out with a carbon working electrode (GCE or BDDE), support electrolyte composition and pH and considering possible interferents. Thus, electroanalytical methods for detection and quantification of 3-Cl-Tyr at carbon electrodes were also developed and proposed.

Effect of biological and anthropogenic habitat sounds on oxidative stress biomarkers and behavior in a key crab species

Soundscapes are characterized by a combination of natural and anthropogenic sounds. This study evaluated the stress effect of biological and anthropogenic sounds characterizing a Man and Biosphere UNESCO wetland, by assessing the protein content, oxidative biomarkers, and behavior of a key crab species (Neohelice granulata), through a tank-laboratory experiment. Biological sounds corresponded to predators of N. granulata (fish and crustacean stimuli), while anthropogenic ones belonged to motorboat passages (boat stimulus). Biochemical results showed differences depending on the sound stimuli used and the crab tissue analyzed. Protein content was higher in hemolymph when crabs were exposed to fish and boat stimuli, and in gills when exposed to boat stimulus. The enzymatic activity in hemolymph showed a decreased GST (fish stimulus) and CAT (fish and boat stimuli) activity, in hepatopancreas a higher GST (crustacean stimulus) and CAT (crustacean and boat stimuli) activity was found, and in gills a higher CAT activity was also observed (crustacean and boat stimuli). Lipid peroxidation was higher only in hemolymph (fish and crustacean stimuli). Protein oxidation was higher in gills (fish stimulus) and hepatopancreas (crustacean stimulus). Behavioral analysis demonstrated that the crab locomotion activity diminished when exposed to diverse sound stimuli. Thus, both sound sources caused physiological and behavioral stress in this species. The results contribute important data to be used in the development of management plans considering the habitat importance in terms of biodiversity, the ecosystem services provided and the role of the studied species.

Vitamin D Deficiency, Excessive Gestational Weight Gain, and Oxidative Stress Predict Small for Gestational Age Newborns Using an Artificial Neural Network Model.

(1) Background: Size at birth is an important early determinant of health later in life. The prevalence of small for gestational age (SGA) newborns is high worldwide and may be associated with maternal nutritional and metabolic factors. Thus, estimation of fetal growth is warranted. (2) Methods: In this work, we developed an artificial neural network (ANN) model based on first-trimester maternal body fat composition, biochemical and oxidative stress biomarkers, and gestational weight gain (GWG) to predict an SGA newborn in pregnancies with or without obesity. A sensibility analysis to classify maternal features was conducted, and a simulator based on the ANN algorithm was constructed to predict the SGA outcome. Several predictions were performed by varying the most critical maternal features attained by the model to obtain different scenarios leading to SGA. (3) Results: The ANN model showed good performance between the actual and simulated data (R2 = 0.938) and an AUROC of 0.8 on an independent dataset. The top-five maternal predictors in the first trimester were protein and lipid oxidation biomarkers (carbonylated proteins and malondialdehyde), GWG, vitamin D, and total antioxidant capacity. Finally, excessive GWG and redox imbalance predicted SGA newborns in the implemented simulator. Significantly, vitamin D deficiency also predicted simulated SGA independently of GWG or redox status. (4) Conclusions: The study provided a computational model for the early prediction of SGA, in addition to a promising simulator that facilitates hypothesis-driven constructions, to be further validated as an application.

Elevated Urinary Biomarkers of Oxidative Damage in Photocopier Operators following Acute and Chronic Exposures.

Inhalation exposures to nanoparticles (NPs) from printers and photocopiers have been associated with upper airway and systemic inflammation, increased blood pressure, and cases of autoimmune and respiratory disorders. In this study we investigate oxidative stress induced by exposures to copier-emitted nanoparticles using a panel of urinary oxidative stress (OS) biomarkers representing DNA damage (8-hydroxydeoxyguanosine, 8-OHdG; 8-hydroxyguanosine, 8-OHG; 5-hydroxymethyl uracil 5-OHMeU), lipid peroxidation (8-isoprostane; 4-hydroxynonenal, HNE), and protein oxidation biomarkers (o-tyrosine, 3-chlorotyrosine, and 3-nitrotyrosine) under conditions of acute (single 6 h exposure, 9 volunteers, 110 urine samples) and chronic exposures (6 workers, 11 controls, 81 urine samples). Urinary biomarkers were quantified with liquid chromatography–tandem mass spectrometry after solid phase extraction sample cleanup. 8-OHdG, 8-OHG, 8-isoprostane, and HNE were significantly elevated in both the acute and chronic exposure study participants relative to the controls. In the acute exposure study, the geometric mean ratios post-/pre-exposure were 1.42, 1.10, 2.0, and 2.25, respectively. Urinary 8-OHG and HNE increased with time to at least 36 h post-exposure (post-/pre-exposure GM ratios increased to 3.94 and 2.33, respectively), suggesting slower generation and/or urinary excretion kinetics for these biomarkers. In chronically exposed operators, the GM ratios of urinary biomarkers relative to controls ranged from 1.52 to 2.94, depending on the biomarker. O-Tyrosine and 5-OHMeU biomarkers were not significantly different from the controls. 3-chlorotyrosine and 3-nitrotyrosine were not detected in the urine samples. We conclude that NPs from photocopiers induce systemic oxidative stress by damaging DNA, RNA, and lipids. Urinary levels of 8-OHdG, 8-OHG, HNE, and 8-isoprostane were orders of magnitude higher than in nanocomposite processing workers, comparable to nano titanium dioxide and fiberglass manufacturing workers, but much lower than in shipyard welding and carbon nanotube synthesis workers. Biomarkers 8-OHdG, 8-OHG, 8-isoprostane, and HNE appear to be more sensitive and robust urinary biomarkers for monitoring oxidative stress to NPs from photocopiers.

PEG35 and Glutathione Improve Mitochondrial Function and Reduce Oxidative Stress in Cold Fatty Liver Graft Preservation.

The need to meet the demand for transplants entails the use of steatotic livers, more vulnerable to ischemia-reperfusion (IR) injury. Therefore, finding the optimal composition of static cold storage (SCS) preservation solutions is crucial. Given that ROS regulation is a therapeutic strategy for liver IR injury, we have added increasing concentrations of PEG35 and glutathione (GSH) to the preservation solutions (IGL-1 and IGL-2) and evaluated the possible protection against energy depletion and oxidative stress. Fatty livers from obese Zücker rats were isolated and randomly distributed in the control (Sham) preserved (24 h at 4 °C) in IGL-0 (without PEG35 and 3 mmol/L GSH), IGL-1 (1 g/L PEG35, and 3 mmol/L GSH), and IGL-2 (5 g/L PEG35 and 9 mmol/L GSH). Energy metabolites (ATP and succinate) and the expression of mitochondrial oxidative phosphorylation complexes (OXPHOS) were determined. Mitochondrial carrier uncoupling protein 2 (UCP2), PTEN-induced kinase 1 (PINK1), nuclear factor-erythroid 2 related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and the inflammasome (NLRP3) expressions were analyzed. As biomarkers of oxidative stress, protein oxidation (AOPP) and carbonylation (DNP derivatives), and lipid peroxidation (malondialdehyde (MDA)–thiobarbituric acid (TBA) adducts) were measured. In addition, the reduced and oxidized glutathione (GSH and GSSG) and enzymatic (Cu–Zn superoxide dismutase (SOD), CAT, GSH S-T, GSH-Px, and GSH-R) antioxidant capacities were determined. Our results showed that the cold preservation of fatty liver graft depleted ATP, accumulated succinate and increased oxidative stress. In contrast, the preservation with IGL-2 solution maintained ATP production, decreased succinate levels and increased OXPHOS complexes I and II, UCP2, and PINK-1 expression, therefore maintaining mitochondrial integrity. IGL-2 also protected against oxidative stress by increasing Nrf2 and HO-1 expression and GSH levels. Therefore, the presence of PEG35 in storage solutions may be a valuable option as an antioxidant agent for organ preservation in clinical transplantation.

A UPLC-MS/MS method for the determination of oxidative stress biomarkers in amniotic fluid

Oxidative stress in the fetal period is associated with preterm birth as well as short and long-term adverse clinical outcomes. Here, an Ultra-Performance Liquid Chromatography–tandem Mass Spectrometry (UPLC-MS/MS) method for the simultaneous quantification of biomarkers of oxidative stress-derived damage to proteins and DNA in amniotic fluid (AF) samples is presented. Appropriate accuracy and precision levels, as well as sensitivity with limits of detection in the low nanomolar (<2 nM) range were achieved. The analytical method was applied to a set of AF samples and reference ranges of the biomarker panel are presented. Median concentrations of biomarkers of protein oxidation (ortho-, 3-chloro-, and 3-nitrotyrosine) and their precursors (para-tyrosine and phenylalanine) ranged between 0.6 and 3 nM and 23 and 30 μM, respectively, while levels of a biomarker of DNA-oxidation (8-hydroxydeoxyguanosine, 8OHdG) and its precursor (2′-deoxyguanosine) were found to be 0.18 and 3 nM, respectively. Detection frequencies of all metabolites were 100% with exception of 3-chlorotyrosine (3Cl-Tyr) and 8OHdG, that were only detected in 8% of samples. The developed method may be applied in research studies focusing on oxidative stress-related complications during pregnancy.