Concentrations Of Oxidative Stress Biomarkers Research Articles

The halotolerant exopolysaccharide-producing Rhizobium azibense increases the salt tolerance mechanism in Phaseolus vulgaris (L.) by improving growth, ion homeostasis, and antioxidant defensive enzymes

Globally, agricultural productivity is facing a serious problem due to soil salinity which often causes osmotic, ionic, and redox imbalances in plants. Applying halotolerant rhizobacterial inoculants having multifarious growth-regulating traits is thought to be an effective and advantageous approach to overcome salinity stress. Here, salt-tolerant (tolerating 300 mM NaCl), exopolysaccharide (EPS) producing Rhizobium azibense SR-26 (accession no. MG063740) was assessed for salt alleviation potential by inoculating Phaseolus vulgaris (L.) plants raised under varying NaCl regimes. The metabolically active cells of strain SR-26 produced a significant amount of phytohormones (indole-3-acetic acid, gibberellic acid, and cytokinin), ACC deaminase, ammonia, and siderophore under salt stress. Increasing NaCl concentration variably affected the EPS produced by SR-26. The P-solubilization activity of the SR-26 strain was positively impacted by NaCl, as demonstrated by OD shift in NaCl-treated/untreated NBRIP medium. The detrimental effect of NaCl on plants was lowered by inoculation of halotolerant strain SR-26. Following soil inoculation, R. azibense significantly (p ≤ 0.05) enhanced seed germination (10%), root (19%) shoot (23%) biomass, leaf area (18%), total chlorophyll (21%), and carotenoid content (32%) of P. vulgaris raised in soil added with 40 mM NaCl concentration. Furthermore, strain SR-26 modulated the relative leaf water content (RLWC), proline, total soluble protein (TSP), and sugar (TSS) of salt-exposed plants. Moreover, R. azibense inoculation lowered the concentrations of oxidative stress biomarkers; MDA (29%), H2O2 content (24%), electrolyte leakage (31%), membrane stability (36%) and Na+ ion uptake (28%) when applied to 40 mM NaCl-treated plants. Further, R. azibense increases the salt tolerance mechanism of P. vulgaris by upregulating the antioxidant defensive responses. Summarily, it is reasonable to propose that EPS-synthesizing halotolerant R. azibense SR-26 should be applied as the most cost-effective option for increasing the yields of legume crops specifically P. vulgaris in salinity-challenged soil systems.

Atherogenicity, Oxidative Stress, Heavy Metals and Bioelements Status in Hypertensive Nigerians in an Urban Population

Objectives: This study investigated levels of measured parameters; bio-elements (zinc, copper, selenium, chromium, and manganese), heavy metals (cadmium and lead), oxidative stress biomarkers (vitamin C, Vitamin E, reduced Glutathione-GSH and malondialdehyde-MDA) and lipid profile (cholesterol-CHOL, triglyceride- TG, high-density lipoprotein- HDL, low-density lipoprotein- LDL and VLDL) in primary hypertensive individuals.
 Materials and Methods: A total of 74 confirmed hypertensive individuals (30 males, 44 females) of 30-55 years (test subjects) and 46 (22males, 24 females) age-matched apparently healthy normotensive individuals (control) were involved in this study. Atomic absorption spectrophotometer was used to determine the concentrations of bio-elements and toxic metals while spectrophotometric methods were used for the concentrations of oxidative stress biomarkers and lipid fractions.
 Results: Comparative analysis between test and control subjects showed significantly reduced concentrations of vitamins C and E, GSH, the bio-elements, HDL and Zinc/Copper ratio. Significantly elevated concentrations of the toxic metals, MDA, CHOL, TG, LDL, and VLDL, the atherogenic indices- LDL/HDL, TC/HDL, and TG/HDL as well as Cadmium/ Zinc ratio. There was indirect association between the bio-elements and atherogenic lipid fractions but a direct correlation with HDL. Also, negative correlations were observed between the heavy metals and the antioxidants biomolecules.
 Conclusion: The concentrations of the measured bio-elements, vitamins C and E, GSH and HDL were significantly lower in hypertensive individuals while the levels of heavy metals, cholesterol, TG, LDL and MDA were significantly higher.

Association of shift work with oxidative stress and alteration of fasting plasma glucose level in Chinese adults.

This study aimed to assess the association of shift work with blood glucose and the mediating role of oxidative stress. Fasting plasma glucose (FPG) and urinary concentrations of oxidative stress biomarkers (8-hydroxy-2'-deoxyguanosine [8-OHdG], 4-hydroxy-2-nonenal-mercapturic acid, and 8-iso-prostaglandin F2α [8-isoPGF2α ]) were measured among 831 participants. Positive dose-response relationships amongshift work duration, FPG (ptrend < 0.001), and abnormal glucose regulation (AGR; ptrend = 0.035) were found. Compared with participants without shift work, three-shift work was associated with a higher level of FPG (percentage change: 6.49%, 95% CI: 4.21%-8.83%) and a higher prevalence of impaired fasting glucose (odds ratio: 1.886, 95% CI: 1.114-3.192) and AGR (odds ratio: 1.929, 95% CI: 1.197-3.111). A dose-response relationship was found between shift work duration and 8-OHdG (ptrend = 0.002) and 8-isoPGF2α (ptrend = 0.019). Urinary 8-OHdG and 8-isoPGF2α partially mediated the association between shift work duration and FPG levels and the prevalence of impaired fasting glucose and AGR, with mediating proportions ranging from 4.77% to 20.76%. These findings suggest that shift work is positively associated with blood glucose, and the association ispartially mediated by oxidative stress.

Preterm birth prediction in pregnant women over than 35 years. Observational analytical cohort study.

Introduction. Premature birth can occur at any age; however, it is important to note that the risk of preterm birth can vary based on several factors, including the mother’s medical history, general health, and lifestyle. There is thought to be a relationship between maternal age and the risk of preterm birth, although the exact nature of this relationship may vary. At the same time, it is considered for ages over 35, an increased risk factor for the evolution of pregnancies with complications. Pregnant women over 35 face a higher risk of premature birth. This increased risk may be associated with age-related factors such as underlying health conditions, higher rates of multiple pregnancies (due to fertility treatments), and potential placental dysfunction. Material and methods. In the given study, the biomarkers IL-6, IL-8, IL-10, IL-12, SDF-1α and VEGF in amniotic fluid (AF) and maternal blood were investigated, considering the above as predictive of premature birth outcome. At the same time, the oxidative stress status of maternal blood and amniotic fluid collected in the second trimester of pregnancy was identified. Results. In the research, we obtained statistically significant increases in the biomarkers AAT-isopropyl, G-GTP, HPL-isopropyl from the amniotic fluid taken from pregnant women over 35 years of age in the second trimester of pregnancy in those pregnant women who had a preterm birth. In the serum of pregnant women with premature birth, an increase in the concentration of carnosine-histidine peptides, G-GTP, GR and SH (thiol) groups was identified, and the decrease in the values of SDF 1α, HPL – hexane and IL-12 were statistically significant in the serum pregnant women compared to that of the amniotic fluid. Identifying the values of biochemical mediators during pregnancy can be a method of predictive diagnosis Conclusions. Our study shows the relationship between some concentrations of oxidative stress biomarkers (AAT-isopropyl, HPL-isopropyl and G-GTP, IL-12) in amniotic fluid, and values of (Carnosine Histidine Peptide, GR and SH and SDF-1α) in the serum of pregnant women, in the second trimester of pregnancy.

Alteration of Blood Oxidative Stress Status in Patients with Thoracic Aortic Dissection: A Pilot Study.

Thoracic aortic dissection (TAD) is a life-threatening condition which usually occurs on an aneurysmal aortic wall. Although increasing data have shown that inflammation and oxidative stress play an important role in the patho-physiology of dissection, systemic oxidative stress status (OSS) has not been clearly determined in patients suffering from TAD. A cohort of 115 patients presenting type A or B TAD were admitted to our center from 2013 to 2017. Out of this cohort, 46 patients were included in a study on dissected aorta (LIege study on DIssected Aorta: LIDIA). In 18 out of the 46 patients, systemic OSS parameters were evaluated after TAD diagnosis by determination of eight different antioxidants, four trace elements, two markers of oxidative lipid damage and two inflammatory markers. The 18 TAD patients included 10 men and 8 women (median age: 62 years; interquartile range: 55-68) diagnosed with type A (N = 8) or B (N = 10) TAD. Low plasma levels of vitamin C, β-carotene, γ-tocopherol, thiol proteins, paraoxonase and selenium were observed in these 18 patients. By contrast, the concentration of copper and total hydroperoxides, copper/zinc ratio, as well as inflammatory markers, were higher than the reference intervals. No difference was observed in oxidative stress biomarker concentrations between type A and B TAD patients. This pilot study, limited to 18 TAD patients, revealed a heightened systemic OSS, determined at 15.5 days (median) after the initial diagnosis, in those TAD patients without complications (malperfusion syndrome and aneurysm formation). Larger studies on biological fluids are needed to better characterize the oxidative stress and interpret its consequence in TAD disease.

Assessment of the excretion of oxidative stress biomarkers and anabolic steroids based on sewage: A case study of college students and the general population

The use of wastewater-based epidemiology to evaluate the health and lifestyle of the population is a novel research interest. However, studies concerning the excretion of endogenous metabolites due to oxidative stress and the consumption of anabolic steroids have rarely been involved. In this study, we compared the effects of events such as final examination and sports meeting on the levels of four oxidative stress biomarkers (8-isoPGF2α, HNE-MA, 8-OHdG, and HCY) and four prohibited anabolic steroids (Testosterone, Androstenedione, Boldenone, and Metandienone) in sewage, using university students and urban populations as studying target. It was found that the per capita mass load of the four oxidative stress biomarkers 8-isoPGF2α, HNE-MA, 8-OHdG, and HCY in the sewage of Guangzhou urban area and university town were 256.6 ± 76.1, 9.4 ± 3.8, 1.1 ± 0.5, and 0.9 ± 0.4 mg/d/1000, respectively. The mean mass load of 8-isoPGF2α was significantly higher than that before the COVID-19 pandemic (74.9 ± 29.6 mg/d/1000 people, P < 0.05). The per capita load levels of oxidative stress biomarkers were significantly higher (P < 0.05) during the 2022 exam week relative to the pre-exam period, indicating that the exams caused transient stress to students. The per capita mass load of androgenic steroids was 77.7 mg/d/1000 people. There was an increase in the per capita load level of androgenic steroids during the provincial sports meeting. In this study, we quantified the concentration of oxidative stress biomarkers and androgenic steroids in the sewage and better realized the application of WBE on the health level and lifestyle of the population during special events.

Use of a Biostimulant to Mitigate the Effects of Excess Salinity in Soil and Irrigation Water in Tomato Plants.

Global warming is linked to progressive soil salinisation, which reduces crop yields, especially in irrigated farmland on arid and semiarid regions. Therefore, it is necessary to apply sustainable and effective solutions that contribute to enhanced crop salt tolerance. In the present study, we tested the effects of a commercial biostimulant (BALOX®) containing glycine betaine (GB) and polyphenols on the activation of salinity defense mechanisms in tomato. The evaluation of different biometric parameters and the quantification of biochemical markers related to particular stress responses (osmolytes, cations, anions, oxidative stress indicators, and antioxidant enzymes and compounds) was carried out at two phenological stages (vegetative growth and the beginning of reproductive development) and under different salinity conditions (saline and non-saline soil, and irrigation water), using two formulations (different GB concentrations) and two doses of the biostimulant. Once the experiments were completed, the statistical analysis revealed that both formulations and doses of the biostimulant produced very similar effects. The application of BALOX® improved plant growth and photosynthesis and assisted osmotic adjustment in root and leaf cells. The biostimulant effects are mediated by the control of ion transport, reducing the uptake of toxic Na+ and Cl- ions and favoring the accumulation of beneficial K+ and Ca2+ cations, and a significant increase in leaf sugar and GB contents. BALOX® significantly reduced salt-induced oxidative stress and its harmful effects, as evidenced by a decrease in the concentration of oxidative stress biomarkers, such as malondialdehyde and oxygen peroxide, which was accompanied by the reduction of proline and antioxidant compound contents and the specific activity of antioxidant enzymes with respect to the non-treated plants.

331 Mitochondrial stress contributes to atopic dermatitis

Atopic dermatitis (AD) is a complex disease characterized by eczematous lesions over dry skin and local and systemic oxidative stress. Indeed, patients with AD display increased concentrations of oxidative stress biomarkers in the urine, blood, and saliva. Although the source of ROS in AD is uncertain, dysfunctional mitochondria might be involved in excessive oxidative stress in AD skin. In this study, we investigated oxidative stress in AD epidermis by using a mouse model of AD, i.e. flaky tail (ft/ft) mice, and primary keratinocytes and skin biopsies from AD patients.

Urinary 2,4-dichlorophenoxyacetic acid in Chinese pregnant women at three trimesters: Variability, exposure characteristics, and association with oxidative stress biomarkers.

Widespread exposure to herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) could have potential adverse health effects on pregnant women. However, related data are scarce. This study aimed to characterize 2,4-D exposure among three trimesters of pregnancy and to explore the relationship of 2,4-D with oxidative stress biomarkers [i.e., 8-hydroxy-2'-deoxyguanosine (8-OHdG), 8-hydroxy guanosine (8-OHG), and 4-hydroxy nonenal mercapturic acid (HNEMA)] in urine. The present study analyzed 3675 urine samples of 1225 women (across the three trimesters of pregnancy) in Wuhan, central China. 2,4-D was detectable in 97.4% of the urine samples. The median unadjusted concentration of 2,4-D was 0.12ng/mL, and the corresponding concentration adjusted by urinary specific gravity (SG-adjusted) was 0.13ng/mL. The intraclass correlation coefficient of 2,4-D (SG-adjusted concentrations) was 0.07 across the three trimesters. Significantly higher urinary levels of 2,4-D were found in samples from younger pregnant women/samples collected during winter. In addition, significantly positive association between urinary concentrations of oxidative stress biomarkers and 2,4-D were found in repeated analysis; an interquartile range increase in 2,4-D was significantly (p<0.001) associated with a 20.8% increase in 8-OHG, a 26.7% increase in 8-OHdG, and a 30.7% increase in HNEMA, respectively. Such associations were also found in trimester-specific analyses. This is the first time to quantify the urinary 2,4-D of pregnant women in China, and this study found significantly positive associations of 2,4-D with oxidative stress biomarkers. Further studies are needed to verify such associations and explore other potential adverse effects of 2,4-D exposure.

Urinary Concentrations of Oxidative Stress Biomarkers Across Pregnancy: Variability of Measures in Two Birth Cohorts

Urinary Concentrations of Oxidative Stress Biomarkers Across Pregnancy: Variability of Measures in Two Birth Cohorts

The association between urinary glyphosate and aminomethyl phosphonic acid with biomarkers of oxidative stress among pregnant women in the PROTECT birth cohort study

BackgroundGlyphosate is a widely used herbicide in global agriculture. Glyphosate and its primary environmental degradate, aminomethyl phosphonic acid (AMPA), have been shown to disrupt endocrine function and induce oxidative stress in in vitro and animal studies. To our knowledge, these relationships have not been previously characterized in epidemiological settings. Elevated urinary levels of glyphosate and AMPA may be indicative of health effects caused by previous exposure via multiple mechanisms including oxidative stress. MethodsGlyphosate and AMPA were measured in 347 urine samples collected between 16 and 20 weeks gestation and 24–28 weeks gestation from pregnant women in the PROTECT birth cohort. Urinary biomarkers of oxidative stress, comprising 8-isoprostane-prostaglandin-F2α (8-iso-PGF2α), its metabolite 2,3-dinor-5,6-dihydro-15-F2 t-isoprostane (8-isoprostane metabolite) and prostaglandin-F2α (PGF2α), were also measured. Linear mixed effect models assessed the association between exposures and oxidative stress adjusting for maternal age, smoking status, alcohol consumption, household income and specific gravity. Potential nonlinear trends were also assessed using tertiles of glyphosate and AMPA exposure levels. ResultsNo significant differences in exposure or oxidative stress biomarker concentrations were observed between study visits. An interquartile range (IQR) increase in AMPA was associated with 9.5% (95% CI: 0.5–19.3%) higher 8-iso-PGF2α metabolite concentrations. Significant linear trends were also identified when examining tertiles of exposure variables. Compared to the lowest exposure group, the second and third tertiles of AMPA were significantly associated with 12.8% (0.6–26.5%) and 15.2% (1.8–30.3%) higher 8-isoprostane metabolite, respectively. An IQR increase in glyphosate was suggestively associated with 4.7% (−0.9 to 10.7%) higher 8-iso-PGF2α. ConclusionsUrinary concentrations of the main environmental degradate of glyphosate, AMPA, were associated with higher levels of certain oxidative stress biomarkers. Associations with glyphosate reflected similar trends, although findings were not as strong. Additional research is required to better characterize the association between glyphosate exposure and biomarkers of oxidative stress, as well as potential downstream health consequences.

Long-term effects of smoking on serum concentrations of oxidative stress biomarkers: Results of a large, population-based cohort study

IntroductionCross-sectional studies have consistently shown an association between current smoking and oxidative stress biomarkers. However, no longitudinal studies have been performed so far. MethodsThe oxidative stress biomarkers “total thiol groups of serum proteins” (TTP), and “derivatives of reactive oxygen metabolites” (D-ROM) were measured in serum samples of 3835 participants of a population-based, German cohort study of older adults (age: 60–84 years) with repeated measurements for 2834 participants three years later. Multivariable linear regression models were applied and β-coefficients with 95% confidence intervals were obtained. ResultsIn both cross-sectional and longitudinal analysis, current smoking was statistically significantly associated with increased D-ROM levels, and a dose-response relationship between the amount of daily tobacco consumption and the D-ROM concentrations was observed that plateaued at ≥15 g of tobacco consumption per day. Former smoking was also associated with D-ROM levels. Only former smokers who quitted smoking more than 10 years ago had no increased D-ROM levels compared to never smokers. There was neither a cross-sectional nor longitudinal association between any of the smoking variables and TTP levels. ConclusionThis large population-based cohort of older German adults suggests that smoking has long-term effects on the oxidative stress burden. The further increasing D-ROM levels of current smokers at an older age and the observation that it may take more than 10 years until the redox balance is restored are solid arguments for quitting smoking as soon as possible at any age.

The association between urinary glyphosate metabolites and biomarkers of oxidative stress among pregnant women in PROTECT birth cohort study

Background: Glyphosate is a widely used herbicide in the global agriculture industry. Glyphosate and its primary metabolite, aminomethyl phosphonic acid (AMPA), have been shown to disrupt endocrine function and induce oxidative stress within in vitro and animal studies. To our knowledge, these relationships have not been previously characterized in epidemiological settings. Elevated urinary levels of glyphosate and AMPA may impact the health of vulnerable populations such as pregnant women via multiple mechanisms including oxidative stress. Methods: Glyphosate and AMPA were measured in 347 urine samples collected at multiple visits from pregnant women in the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) birth cohort. Urinary biomarkers of oxidative stress, comprising 8-isoprostane-prostaglandin-F2a (8-iso-PGF2a), its main metabolite 2,3-dinor-5,6-dihydro-15-F2t-isoprostane (8-iso-PGF2a metabolite) and prostaglandin-F2a (PGF2a), were also measured. One-way ANOVA tests evaluated differences in exposure and oxidative stress biomarker concentrations between study visits. Linear mixed effect models assessed the association between exposures and oxidative stress adjusting for maternal age, smoking status, alcohol consumption, household income and specific gravity. Results: No significant differences in exposure or oxidative stress biomarker concentrations were observed between study visits. An interquartile range (IQR) increase in AMPA was associated with 9.5% (95% CI: 0.5%-19.3%) higher 8-iso-PGF2a metabolite. Compared to the lowest exposure group, the second and third tertiles of AMPA were significantly associated with 12.8% (0.6%-26.5%) and 15.2% (1.8%-30.3%) higher 8-iso-PGF2a metabolite, respectively. An IQR increase in glyphosate was suggestively associated with 4.7% (-0.9%-10.7%) higher 8-iso-PGF2a. Conclusions: Urinary concentrations of the main metabolite of glyphosate, AMPA, were associated with higher levels of certain oxidative stress biomarkers. Associations with glyphosate reflected similar trends, although findings were not as strong. Additional research is required to better characterize the association between glyphosate exposure and biomarkers of oxidative stress, as well as potential downstream health consequences.

Indoor PM2.5 Alpha-Radioactivity is Associated with Biomarkers of Oxidative Stress in COPD Patients

Introduction: Radon decays into progeny that attach to indoor air pollution particles and form unattached clusters. After inhalation, we hypothesize that these serve as vectors for radioisotopes that emit radiation (including α-radioactivity) that promote oxidative damage in patients with COPD.Methods: We recruited 140 patients (97% men, mean (SD) age 72.8 (8.3)) with COPD at VA Boston 5/2013-3/2017 who ran a micro-environmental PM2.5 sampler in their home for 1 week up to 4 times a year (n=414 samples). Samples were analyzed for PM2.5 and black carbon (BC). In 2019, α-radioactivity was measured on each PM2.filter. Since 210Pb (t½=22 years), a Rn progeny, is a parent of 210Po (t½=138 days, α-radiation emitter), α-radioactivity reflects formation of 210Po from 210Pb. Based on the 210Pb decay constant and sampled air volume, α-radioactivity during sampling was estimated. Urinary concentrations of oxidative stress biomarkers, 8-hydroxy-2’-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) were assessed. Mixed effects models with a random intercept for each subject were used to examine associations adjusting for age, race, season, urine collection time, BMI, creatinine, diabetes, heart disease, ambient temperature, humidity, and indoor BC and PM2.5.Results: Median (IQR) PM2.5 α-radioactivity=1.5 (0.64) mBq/m3 (equivalent to 0.056 (0.024) pCi/L); PM2.5=6.9 (5.7) µg/ m3; BC=0.58 (0.27) µg/m3. There was a positive association between natural log (α-radioactivity) and 8-OHdG [5.2% increase (95% CI: 0.9-9.7%) per IQR] and MDA [2.0% increase (95% CI: -2.6-6.8%) per IQR]. Results for 8-OHdG were similar adjusting for PM2.5 (5.4%; 95% CI: 1.1-10.0%) and BC (4.6%; 95% CI: 0.1-9.2%). Results for MDA were similar adjusting for PM2.5 (1.9%; 95% CI: -2.8-6.8%) and were reduced adjusting for BC [0.5%; 95% CI: -4.2-5.4%).Conclusions: Indoor PM2.5 α-radioactivity reflecting 210Pb was positively associated with increased DNA oxidation (8-OHdG) and lipid peroxidation (MDA) in participants with COPD.Funding: ES029637, ES019853, USEPA grant RD-835872

Omega-3 fatty acid supplement use and oxidative stress levels in pregnancy.

Oxidative stress is a biological imbalance in reactive oxygen species and antioxidants. Increased oxidative stress during pregnancy has been associated with adverse birth outcomes. Omega-3 fatty acid (n-3 FA) supplementation may decrease oxidative stress; however, this relationship is seldom examined during pregnancy. This study assessed the association between n-3 FA supplement use during pregnancy and urinary oxidative stress biomarker concentrations. Data came from The Infant Development and the Environment Study (TIDES), a prospective cohort study that recruited pregnant women in 4 US cities between 2010–2012. Third trimester n-3 FA intake was self-reported. Third trimester urinary 8-iso-prostaglandin F2α (8-iso-PGF2α) was measured as an oxidative stress biomarker. Additionally, we measured the major metabolite of 8-iso-PGF2α and Prostaglandin F2α (PGF2α) and utilized the 8-iso-PGF2α to PGF2α ratio to calculate the change in 8-iso-PGF2α reflecting oxidative stress versus inflammation. Adjusted linear models were used to determine associations with control for confounding. Of 725 women, 165 reported n-3 FA supplement use in the third trimester. In adjusted linear models, n-3 FA use was associated with 10.2% lower levels of 8-iso-PGF2α (95% Confidence Interval [CI]: -19.6, 0.25) and 10.3% lower levels of the metabolite (95% CI: -17.1, -2.91). No associations were observed with PGF2α. The lower levels of 8-iso-PGF2α appeared to reflect a decrease in oxidative stress (percent change with supplement use: -18.7, 95% CI: -30.1, -5.32) rather than inflammation. Overall, third trimester n-3 FA intake was associated with lower concentrations of 8-iso-PGF2α and its metabolite, suggesting a decrease in maternal oxidative stress during pregnancy.

Associations between psychosocial stress and oxidative stress during pregnancy in Puerto Rico

TPS 742: Adverse birth outcomes 1, Exhibition Hall, Ground floor, August 27, 2019, 3:00 PM - 4:30 PM Background/Aim: Psychosocial stress during pregnancy has been associated with adverse birth outcomes including preterm birth. While hypothalamic-pituitary-axis activation is thought to be the primary driver, oxidative stress and inflammation may also be involved mechanistically. We used data from the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) cohort (N=476), which examines environmental risk factors for preterm birth in the Northern Karst region of Puerto Rico, to examine associations between psychosocial stress measures, demographic characteristics, and urinary oxidative stress biomarker concentrations. Methods: Perceived stress, depression, negative life experiences, neighborhood perceptions, and social support were self-reported in questionnaires administered during pregnancy. Responses were grouped into tertiles for analysis, where the highest tertile corresponded to highest level of psychosocial stress. Urinary concentrations of 8-iso-prostaglandin F2α (8-iso-PGF2α), its primary metabolite, and prostaglandin F2α (PGF2α) were measured at three study visits (median 18, 24, 28 weeks gestation) and averaged to reflect oxidative stress or inflammation across pregnancy. Geometric means and standard deviations were used to examine distributions of biomarkers across demographic characteristics. Linear models were used to examine adjusted associations between tertiles of psychosocial stress and oxidative stress biomarkers. Results: Average levels of 8-iso-PGF2α, its metabolite, and PGF2α were higher among pregnant women who were between 18-24 compared to 25-29 years of age, who had public compared to private insurance, and who were unemployed compared to employed (p-value<0.05). However, no associations were observed between tertiles of psychosocial stress measures and biomarker concentrations. Notably, compared to other populations, there are relatively low levels of psychosocial stress in PROTECT. Conclusions: Psychosocial stress during pregnancy, as indicated by self-reported questionnaire measures, was not associated with biomarkers of oxidative stress and inflammation in the PROTECT population. However, results from our study suggest that these biomarkers are elevated among women of lower socio-economic status, which is typically associated with stress.

Associations between socioeconomic status, psychosocial stress, and urinary levels of 8-iso-prostaglandin-F2α during pregnancy in Puerto Rico

BackgroundLower socioeconomic status (SES) and psychosocial stress during pregnancy have been associated with adverse birth outcomes. While hypothalamic-pituitary-axis activation is thought to be the primary driver, oxidative stress may also be involved mechanistically. We used data from the Puerto Rico Testsite for Exploring Contamination Threats (PROTECT) cohort (N=476) to examine associations between self-reported psychosocial stress measures, SES indicators, and urinary oxidative stress biomarker concentrations, hypothesizing that women with lower SES and increased psychosocial stress would have elevated oxidative stress biomarkers. MethodsMaternal age, education, marital status, insurance status, alcohol use and smoking status were obtained via self-reported questionnaires and were used as indicators of SES. Perceived stress, depression, negative life experiences, neighborhood perceptions, and social support were self-reported in questionnaires administered during pregnancy. Responses were grouped into tertiles for analysis, where the highest tertile corresponded to highest level of psychosocial stress. Urinary concentrations of 8-iso-prostaglandin F2α (8-iso-PGF2α) and its primary metabolite were measured at three study visits (median 18, 24, 28 weeks gestation) and averaged to reflect oxidative stress across pregnancy. Linear models were used to examine associations between SES indicators, tertiles of psychosocial stress and oxidative stress biomarkers. ResultsAverage levels of 8-iso-PGF2α and the 8-iso-PGF2α metabolite were higher among pregnant women who were younger, who had public compared to private insurance, and who were unemployed compared to employed. However, no associations were observed between psychosocial stress measures and biomarker concentrations in adjusted analyses. ConclusionsPsychosocial stress during pregnancy, as indicated by self-reported questionnaire measures, was not associated with biomarkers of oxidative stress in the PROTECT study. However, results suggest that these biomarkers are elevated among women of lower SES, which is typically associated with stress. Notably, compared to other populations, self-reported psychosocial stress measures were lower in PROTECT compared to other populations.

Effects of astaxanthin and canthaxanthin on oxidative stress biomarkers in rainbow trout

ABSTRACTFarmed trout are commonly fed carotenoid-enriched diets during the finishing period to acquire typical red-to-pink flesh color in salmonid muscle. The aim of this study was to examine the effects of two xanthophylls, astaxanthin (Ax) or canthaxanthin (Cx), administered individually or in combination, on oxidative stress biomarkers in kidney and liver of rainbow trout. Specimens were fed Ax (75 mg/kg) or Cx (25 mg/kg) individually or in combination in the diets for 8 weeks. Changes in concentration of oxidative stress biomarkers, including total glutathione, superoxide dismutase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase, were recorded in Ax- and Cx-dosed trout. These two carotenoids, predominantly Cx, initiated enzymatic responses in rainbow trout. It is noteworthy that lipid peroxidation processes were not apparent in all Ax or Cx-dosed trout. Further, both combined xanthophylls did not exert significant synergistic effects in liver and kidney. Biomarker responses were generally altered in both tissues through the 4 and 8 weeks suggesting that different time-dependent mechanisms led to enhanced antioxidant defense in Ax and/or Cx-fed trout. Data demonstrated that these two xanthophylls did not exert detrimental effects on rainbow trout.

Salivary myeloperoxidase and malondialdehyde are increased in patients exhibiting an asymptomatic mandibular impacted third molar.

BackgroundTo determine whether saliva is a good means of evaluating concentrations of oxidative stress biomarkers, analyzing the correlation between concentrations in saliva and in follicular tissue, and to compare biomarker concentrations in patients with one asymptomatic mandibular impacted third molar (MITM) (before extraction) with a healthy control, and to determine how biomarkers are modified by extraction.Material and Methods80 patients with one asymptomatic MITM and 80 healthy controls were included. Saliva samples were collected from all subjects (before extraction in the study group) to evaluate Myeloperoxidase (MPO) and Malondialdehyde (MDA) concentrations. Follicular tissues were obtained during surgery to measure biomarkers. One month after extraction, saliva samples were collected to assess changes of oxidative stress.ResultsSalivary MPO and MDA showed positive correlation with concentrations in follicular tissue (MPO: correlation coefficient=0.72, p=0.025; MDA: =0.92, p=0.001). Patients with asymptomatic MITMs showed higher salivary concentrations of oxidative stress biomarkers than healthy control subjects, with statistical significance for both MPO (p<0.001) and MDA (p<0.001). One month after extraction, salivary biomarkers decreased significantly in the study group (p<0.001).ConclusionsSalivary MPO and MDA are higher among patients with one asymptomatic MITM, but these levels decrease significantly one month after surgical extraction. The large decrease in oxidative stress biomarkers could justify third molar extraction despite the absence of symptoms. Key words:Oxidative stress biomarkers, myeloperoxidase, malondialdehyde, impacted third molar, surgical extraction.

Antioxidant capacity and biomarkers of oxidative stress in saliva of khat-chewing patients: a case-control study

The aim of this study was to investigate the antioxidant levels and biomarkers of oxidative stress in saliva from khat-chewing patients compared with controls. Saliva samples were collected from 51 chronic khat chewers and 46 age- and sex-matched controls. Concentrations of oxidative stress biomarkers (malonyl-dialdehyde [MDA], protein carbonyl, and 8-hydroxy-2'-deoxyguanosine) and antioxidant defense (total antioxidant capacity [TAC], superoxide dismutase, glutathione peroxidase, and catalase [CAT) were analyzed. Salivary MDA level in the khat users group (45 ± 9.2 nmol/mL) was significantly increased in comparison with controls (13 ± 2.1 nmol/mL; P < .001), but there were no significant differences between the 2 groups regarding the levels of salivary protein carbonyl and oxidized guanine species. Salivary TAC was significantly reduced in khat users (0.25 ± 0.028 mmol/L) in comparison with controls (0.34 ± 0.037 mmol/L). Salivary CAT level was significantly reduced in khat users (6.0 ± 0.47 U/mL) in comparison with controls (7.7 ± 0.43 units/mL; P <.05), but no significant differences were observed between the 2 groups with regard to salivary superoxide dismutase or glutathione peroxidase levels. Chronic khat chewing is associated with increased levels of salivary MDA and reduced levels of TAC and CAT among a population of adult men in comparison with non-khat-chewing controls. These findings suggest that the pro-oxidative effect of khat chewing may be a contributing mechanism for various oral diseases associated with khat use, including cancer, periodontitis, and caries.