Biomarkers representing key aging-related biological pathways are associated with subclinical atherosclerosis and all-cause mortality: The Framingham Study.

BACKGROUND: Increased oxidative stress, leukocyte telomere length (LTL) shortening, endothelial dysfunction, and lower insulin-like growth factor (IGF)-1 concentrations reflect key molecular mechanisms of aging. We hypothesized that biomarkers representing these pathways are associated with measures of subclinical atherosclerosis and all-cause mortality. METHODS AND RESULTS: We evaluated up to 2,314 Framingham Offspring Study participants (mean age 61 years, 55% women) with available biomarkers of aging: LTL, circulating concentrations of IGF-1, asymmetrical dimethylarginine (ADMA), and urinary F2-Isoprostanes indexed to urinary creatinine. We evaluated the association of each biomarker with coronary artery calcium [ln (CAC+1)] and carotid intima-media thickness (IMT). In multivariable-adjusted linear regression models, higher ADMA levels were associated with higher CAC values (ßADMA per 1-SD increase 0.25; 95% confidence interval [CI] [0.11, 0.39]). Additionally, shorter LTL and lower IGF-1 values were associated with higher IMT values (ßLTL -0.08, 95%CI -0.14, -0.02, and ßIGF-1 -0.04, 95%CI -0.08, -0.01, respectively). During a median follow-up of 15.5 years, 593 subjects died. In multivariable-adjusted Cox regression models, LTL and IGF-1 values were inversely associated with all-cause mortality (hazard ratios [HR] per SD increase in biomarker, 0.85, 95% CI 0.74-0.99, and 0.90, 95% CI 0.82-0.98 for LTL and IGF-1, respectively). F2-Isoprostanes and ADMA values were positively associated with all-cause mortality (HR per SD increase in biomarker, 1.15, 95% CI, 1.10-1.22, and 1.10, 95% CI, 1.02-1.20, respectively). CONCLUSION: In our prospective community-based study, aging-related biomarkers were associated with measures of subclinical atherosclerosis cross-sectionally and with all-cause mortality prospectively, supporting the concept that these biomarkers may reflect the aging process in community-dwelling adults.

Plasma isoprostanoids assessment as Alzheimer's disease progression biomarkers.

Alzheimer's Disease (AD) is the most common neurodegenerative disease worldwide. So, there is a need to identify AD early diagnosis and monitoring biomarkers in blood samples. The aim of this study was to analyse the utility of lipid peroxidation biomarkers in AD progression evaluation. Participants (n = 19) were diagnosed with AD at early stages (Time 0, T0), and they were re-evaluated 2 years later (Time 1, T1). Plasma biomarkers from AD patients were determined at both times. Some analytes, such as dihomo-isoprostanes (17-epi-17-F2t-dihomo-IsoP, 17-F2t-dihomo-IsoP, Ent-7(RS)-7-F2t-dihomo-IsoP), and neuroprostanes (10-epi-10-F4t-NeuroP) showed very high probability of showing an increasing trend over time. Baseline values allowed to develop an affordable preliminary regression model to predict long-term cognitive status. So, some lipid peroxidation biomarkers would deserve consideration as useful progression AD biomarkers. The developed prediction model would constitute an important minimally invasive approach in AD personalized prognosis and perhaps could have some interest also in experimental treatments evaluation.

Interrelationship between renin-angiotensin-aldosterone system and oxidative stress in chronic heart failure patients with or without renal impairment.

We investigated oxidative stress and RAAS biomarkers, as well as their association, in chronic heart failure (CHF) patients on optimized medical therapy, stratified by disease severity or by renal function. Since vitamin D has been shown to attenuate RAAS activation and oxidative stress, we further evaluated the relationship between vitamin D, RAAS and oxidative stress in CHF patients with or without renal impairment. Sixty CHF outpatients were included and stratified by disease severity or by renal function. We quantified urinary hydrogen peroxide, plasma and urinary isoprostanes, plasma total antioxidant status, urinary angiotensinogen (intrarenal RAAS activation biomarker) and plasma angiotensinogen, plasma renin and aldosterone concentration, serum angiotensin-converting enzyme (ACE) activity, plasma angiotensin peptides, and serum total 25-hydroxyvitamin D (S-total 25(OH)D). Severe CHF patients had higher urinary isoprostanes (p = 0.002) and lower S-total 25(OH)D (p = 0.006) compared to mild-to-moderate patients, but no differences were observed for other redox or RAAS biomarkers. Patients with impaired renal function (iRF) had higher urinary angiotensinogen (p = 0.003) and lower S-total 25(OH)D (p = 0.028) compared to those with normal renal function (nRF), while no differences were observed for the remaining RAAS and redox parameters. Several positive correlations between oxidative stress and RAAS biomarkers were detected in iRF patients, while in patients with nRF these correlations were primarily inverse. In CHF-iRF patients, S-25(OD)D was inversely associated with urinary isoprostanes, which in turn were positively associated with plasma angiotensinogen and serum ACE. In conclusion, CHF patients with renal function impairment have increased intrarenal RAAS activation and lower vitamin D values and might benefit from the combination of RAAS blockers with vitamin D and/or antioxidants.

Measurement of Enzymatic and Nonenzymatic Polyunsaturated Fatty Acid Oxidation Products in Plasma and Urine of Macular Degeneration Using LC-QTOF-MS/MS.

Oxidized polyunsaturated fatty acids (PUFA) are associated to pathogenesis of diseases including cardiovascular and neurodegeneration. The novel products are not only biomarkers but also lipid mediators in gene regulation and signaling pathways. Herein, simultaneous quantitation of 28 products derived from nonenzymatic and enzymatic oxidation of PUFA i.e. 5-, 15-F2t -isoprostanes, 7-, 17-F2t -dihomo-isoprostanes, 7-, 17-F2t -dihomo-isofurans, 5-, 8-, 18-F3t -isoprostanes, 4-, 10-, 13-, 14-, 20-F4t -neuroprostanes, 5-, 8-, 9-, 11-,12-, 15-, 20-HETE, 4-, 7-, 11-, 14-, 17-HDHA, RvE1, and NPD1 using LC-(ESI)-QTOF-MS/MS was developed. These products were measurable in a single sample and the analytical time was relative short (~15 min). Furthermore, we showed that the use of internal standards is a requisite to normalize matrix effects and preparation loss for the quantitation. Validation assays indicated the method to be robust for plasma and mid-stream urine sample analysis in particular from those of age-related macular degeneration subjects, where the accuracy of quantitation displayed good repeatability.

Effects of diets high in corn oil or in extra virgin olive oil on oxidative stress in an experimental model of breast cancer.

Experimental evidence highlights the importance of dietetic factors on breast cancer. In this work we aimed to analyze the effects two oils, corn oil (rich in n-6 polyunsaturated fatty acids -PUFA-) and extra virgin olive oil (EVOO), on oxidative stress in an animal model of breast carcinogenesis. Female rats were fed a low-fat control, a high-corn oil, or a high-EVOO diet from weaning or after induction with 7,12-dimethylbenz[a]anthracene at 53 days. Animals were euthanized at 36, 51, 100 and 246 days of age. We analyzed antioxidant enzymes (mRNA and activity of superoxide dismutase, glutathione peroxidase and catalase), non-enzymatic capacity (oxidized and reduced glutathione) and DNA damage (8-oxo-dG) in tumors and mammary gland at different ages. We also analyzed lipid peroxidation (isoprostanes in serum and lipofuscin in liver). Results indicated a decrease in the enzymatic antioxidant capacity and increased oxidative stress in mammary gland of healthy young animals after a short period of high-fat diets intake, followed by an adaptation to chronic dietary intervention. After induction both diets, especially the one high in n-6 PUFA, increased the oxidized glutathione. In tumors no clear effects of the high-fat diets were observed, although in the long-term lipofuscin and 8-oxo-dG suggested greater oxidative damage by effect of the n-6 PUFA-rich diet. Considering the differential effects of these diets on mammary carcinogenesis that we have previously reported, this study suggests that these high-fat diets could have an effect on oxidative stress that would lead to different signaling pathways.

Influence of feeding thermally peroxidized soybean oil on growth performance, digestibility, gut integrity, and oxidative stress in nursery pigs.

The objectives of the current experiments were to evaluate the effect of feeding soybean oil (SO) with different levels of peroxidation on lipid, N, and GE digestibility, gut integrity, oxidative stress, and growth performance in nursery pigs. Treatments consisted diets containing 10% fresh SO (22.5 °C) or thermally processed SO (45 °C for 288 h, 90 °C for 72 h, or 180 °C for 6 h), each with an air infusion of 15 L/min, with postprocessing peroxide values of 7.6, 11.5, 19.1, and 13.4 mEq/kg and p-anisidine values of 1.92, 6.29, 149, and 159, for the 22.5 °C, 45 °C, 90 °C and 180 °C processed SO, respectively. In experiment 1, 64 barrows (7.1 ± 0.9 kg initial BW) were randomly allotted into 2 rooms of 32 pens and individually fed their experimental diets for 21 d, with a fresh fecal sample collected on day 20 for determination of GE and lipid digestibility. In experiment 2, 56 barrows (BW 9.16 ± 1.56 kg) were placed into individual metabolism crates for assessment of GE, lipid, and N digestibility and N retention. Urinary lactulose to mannitol ratio was assessed to evaluate in vivo small intestinal integrity, and urine and plasma were collected to analyze for markers of oxidative stress. Pigs were subsequently euthanized to obtain liver weights and analyze the liver for markers of oxidative stress. In experiment 1, pigs fed the SO thermally processed at 90 °C had reduced ADG (P = 0.01) and ADFI (P = 0.04) compared to pigs fed the other SO treatment groups, with no differences noted among pigs fed the 22.5 °C, 45 °C, and 180 °C SO treatments. No effects of feeding thermally processing SO on dietary GE or lipid digestibility (P > 0.10) were noted in either experiment. In experiment 2, there was no dietary effect of feeding peroxidized SO on the DE:ME ratio, N digestibility, or N retained as a percent of N digested, on the urinary ratio of lactulose to mannitol, on serum, urinary, or liver thiobarbituric acid reactive substances, on plasma protein carbonyls, or on urinary or liver 8-OH-2dG (P > 0.10). In experiment 2, pigs fed the SO thermally processed at 90 °C had the greatest isoprostane concentrations in the serum (P ≤ 0.01) and urine (P ≤ 0.05) compared to pigs fed the unprocessed SO. These results indicate that the change in fatty acid composition and/or the presence of lipid peroxidation products in peroxidized SO may reduce ADG and ADFI in nursery pigs, but appears to have no impact on GE, lipid, or N digestibility, or gut permeability. These data suggest that the presence of lipid peroxidation products may affect certain markers of oxidative stress.

Micro-extraction by packed sorbent combined with UHPLC-ESI-MS/MS for the determination of prostanoids and isoprostanoids in dried blood spots.

This work presents a reliable analytical procedure combining micro-extraction by packed sorbent (MEPS) and ultra-high performance liquid chromatography-electrospray ionization tandem mass spectrometry to determine 8-iso prostaglandin F2α, 8-iso prostaglandin E2 and prostaglandin E2 in dried blood spots (DBSs). To reach this goal, we optimized a fast semi-automated MEPS procedure for the clean-up and pre-concentration of the analytes extracted from a single DBS (50 µL) by a 70:30 v/v methanol:water mixture. Limits of detection of about 20 pg mL-1, satisfactory recoveries (90-110%) and very good intra- and inter-day precisions (RSD ≤10%) were obtained for all the analytes. The innovative addition of internal standards on the filter paper before DBS sampling allowed to compensate changes in the amount of analyte during storage. Since prostanoids and isoprostanoids are biomarkers involved in the pathogenesis and progression of many diseases (e.g. ductal patency, diabetic nephropathy, and acute lung injury), our analytical method offers interesting diagnostic and prognostic opportunities in the medical field. The present method is currently used for the analysis of such biomarkers in DBSs from preterm newborns collected in the clinical setting.

Evaluation of the oxidant-antioxidant balance, isoprostane and quantitative CRP in patients with cutaneous leishmaniasis.

INTRODUCTION: Cutaneous leishmaniasis is a dermal disease caused by several species of the genus Leishmania. It is an endemic disease with 1.2 million new cases occurring annually and mostly in developing countries. Oxidative stress is a condition of an imbalance in oxidant/antioxidant which may play a role in many different pathologic conditions. For the first time in this study, we introduced isoprostane as a reliable index for oxidative stress in patients suffering from leishmaniasis. We also investigated the possible relation between quantitative CRP and this disease. METHOD AND MATERIAL: We collected 5 ml blood of 30 patients in addition to the same sample of the control healthy group. After applying appropriate methods, the plasma and serum specimens were extracted in order to conduct oxidant-antioxidant balance and CRP tests in serum as well as measuring isoprostane factor in plasma. STATISTICAL ANALYSIS: We used T-student, ANOVA as well as linear regression to analyze the gathered data with a 0.05 confidence interval in SPSS environment. RESULTS: The results showed a significant difference between the two groups in terms of the oxidant-antioxidant balance. Also, isoprostane and quantitative CRP levels were substantially higher in patients. There was no significant relationship between the mentioned factors and wound size and number. CONCLUSION: Leishmania Amastigotes plays an important role in disturbing the oxidant-antioxidant balance resulting in inflammation and stress in patients. Furthermore, isoprostane was confirmed as a reliable index for evaluating oxidative stress in patients.

Lipid peroxidation biomarkers correlation with medial temporal atrophy in early Alzheimer Disease.

Alzheimer Disease (AD) is a pathology that causes millions of deaths every year and it also generates severe economic consequences for families and public health systems. Oxidative stress is related to neurodegenerative diseases damage. In fact, brain lipid oxidation could produce brain atrophy. The main objective of this study is the evaluation of atrophy and lipid peroxidation damage in AD patients. We studied medial temporal brain atrophy by magnetic resonance imaging (MRI) and a set of lipid peroxidation biomarkers from plasma samples, respectively. The participants were AD patients in early stages (n = 80) and healthy controls (n = 32). Some lipid peroxidation compounds (neuroprostanes, isoprostanes, neurofurans, isofurans, 17-epi-17-F2t-dihomo-IsoP, PGF2α) in plasma showed statistically significant correlation with medial temporal atrophy. So, they were selected to generate an AD diagnosis model, showing an AUC-ROC of 0.900, close to accuracy achieved by the model based on neuroimaging analysis (AUC-ROC 0.929). In addition, the new model showed suitable specificity, so it could be used as screening test. The developed model based on plasma biomarkers could reflect white and grey matter lipid peroxidation, which occurs in medial temporal lobe in early AD patients. Nevertheless, more studies are needed in this field in order to evaluate specificity against other dementias or neurodegenerative diseases.

Assessment of lipid peroxidation and artificial neural network models in early Alzheimer Disease diagnosis.

OBJECTIVE: Lipid peroxidation constitutes a molecular mechanism involved in early Alzheimer Disease (AD) stages, and artificial neural network (ANN) analysis is a promising non-linear regression model, characterized by its high flexibility and utility in clinical diagnosis. ANN simulates neuron learning procedures and it could provide good diagnostic performances in this complex and heterogeneous disease compared with linear regression analysis. DESIGN AND METHODS: In our study, a new set of lipid peroxidation compounds were determined in urine and plasma samples from patients diagnosed with early Alzheimer Disease (n = 70) and healthy controls (n = 26) by means of ultra-performance liquid chromatography coupled with tandem mass-spectrometry. Then, a model based on ANN was developed to classify groups of participants. RESULTS: The diagnostic performances obtained using an ANN model for each biological matrix were compared with the corresponding linear regression model based on partial least squares (PLS), and with the non-linear (radial and polynomial) support vector machine (SVM) models. Better accuracy, in terms of receiver operating characteristic-area under curve (ROC-AUC), was obtained for the ANN models (ROC-AUC 0.882 in plasma and 0.839 in urine) than for PLS and SVM models. CONCLUSION: Lipid peroxidation and ANN constitute a useful approach to establish a reliable diagnosis when the prognosis is complex, multidimensional and non-linear.

Adrenic acid non-enzymatic peroxidation products in biofluids of moderate preterm infants.

Oxidative stress plays an essential role in processes of signaling and damage to biomolecules during early perinatal life. Isoprostanoids and isofuranoids from the free radical-catalyzed peroxidation of polyunsaturated fatty acids (PUFAs) are widely recognized as reliable biomarkers of oxidative stress. However, their quantification is not straightforward due to high structural similarity of the compounds formed. In this work, a semiquantitative method for the analysis of adrenic acid (AdA, C22:4 n-6) non-enzymatic peroxidation products (i.e. dihomo-isoprostanes and dihomo-isofurans) was developed. The proposed ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) method was applied to the analysis of blood plasma and urine from preterm infants providing information about AdA peroxidation.

A ferroptosis-based panel of prognostic biomarkers for Amyotrophic Lateral Sclerosis.

Accurate patient stratification into prognostic categories and targeting Amyotrophic Lateral Sclerosis (ALS)-associated pathways may pave the way for promising trials. We evaluated blood-based prognostic indicators using an array of pathological markers. Plasma samples were collected as part of a large, phase III clinical trial (Mitotarget/TRO19622) at months 1, 6, 12 and 18. The ALSFRS-r score was used as a proxy of disease progression to assess the predictive value of candidate biological indicators. First, established clinical predictors were evaluated in all 512 patients. Subsequently, pathologic markers, such as proxies of neuronal integrity (Neurofilament light chain and phosphorylated heavy chain), DNA oxidation (8-oxo-2'-desoxyguanosine), lipid peroxidation (4-hydroxy-2-nonenal, isoprostane), inflammation (interleukin-6) and iron status (ferritin, hepcidin, transferrin) were assessed in a subset of 109 patients that represented the whole cohort. Markers of neuronal integrity, DNA and lipid oxidation, as well as iron status at baseline are accurate predictors of disability at 18-month follow-up. The composite scores of these markers in association with established clinical predictors enable the accurate forecasting of functional decline. The identified four biomarkers are all closely associated with 'ferroptosis', a recently discovered form of programmed cell death with promising therapeutic targets. The predictive potential of these pathophysiology-based indicators may offer superior patient stratification for future trials, individualised patient care and resource allocation.

Tampon use, environmental chemicals and oxidative stress in the BioCycle study.

BACKGROUND: Tampons are used by up to 86% of US women and are a rarely considered potential source of pesticide and metal exposure. Tampons may be of particular concern given the likely higher absorption that occurs in the vagina. Our objective was to examine the potential associations between tampon use and metal concentrations, and biomarkers of inflammation and oxidative stress among healthy women. METHODS: We used information from a prospective cohort of 259 regularly menstruating women, aged 18-44, followed for two menstrual cycles. Tampon use was assessed using information provided in participant study diaries. Metal concentrations were measured from a blood sample collected at enrollment. Oxidative stress and inflammation biomarker concentrations were determined from blood samples collected at up to 8 clinic visits for each cycle. Linear regression models were used to estimate associations of tampon use with metal exposure, and linear mixed models to estimate associations of tampon use with inflammation and oxidative stress biomarkers at different times during the menstrual cycle. RESULTS: We observed non-significantly higher mean levels of mercury for tampon users compared to non-tampon users (exp(ß) = 1.25, 95% CI = 0.93, 1.68). We found no evidence of an association between tampon use and inflammation biomarkers. We observed consistently higher isoprostane levels, an oxidative stress biomarker, among tampon users compared to non-tampon users (e.g. exp.(ß) = 1.05, 95%CI = 0.96, 1.16, for the average isoprostane during the menstruating week); however, these results were not statistically significant. CONCLUSIONS: While our results are not statistically significant, we observed suggestive associations between tampon use and elevated levels of mercury and oxidative stress biomarkers. Although our finding should be interpreted in light of our limitations, they indicate that tampons may be a source of exposure to metals and chemicals that have been largely ignored, and any related health effects are an important public health concern.

Prenatal exposure to particulate matter and ozone: Bulky DNA adducts, plasma isoprostanes, allele risk variants, and neonate susceptibility in the Mexico City Metropolitan Area.

Mexico City's Metropolitan Area (MCMA) includes Mexico City and 60 municipalities of the neighbor states. Inhabitants are exposed to emissions from over five million vehicles and stationary sources of air pollutants such as particulate matter (PM) and ozone. MCMA PM contains elemental carbon and organic carbon (OC). OCs include polycyclic aromatic hydrocarbons (PAHs), many of which induce mutagenic and carcinogenic DNA adducts. Gestational exposure to air pollution has been associated with increased risk of intrauterine growth restriction, preterm birth or low birth weight risk, and PAH-DNA adducts. These effects also depend on the presence of risk alleles. We investigated the presence of bulky PAH-DNA adducts, plasma 8-iso-PGF2α (8-iso-prostaglandin F2α ) and risk allele variants in neonates cord blood and their non-smoking mothers' leucocytes from families that were living in a highly polluted area during 2014-2015. The presence of adducts was significantly associated with both PM2.5 and PM10 levels, mainly during the last trimester of gestation in both neonates and mothers, while the last month of pregnancy was significant for the association between ozone levels and maternal plasma 8-iso-PGF2α . Fetal CYP1B1*3 risk allele was associated with increased adduct levels in neonates while the presence of the maternal allele significantly reduced the levels of fetal adducts. Maternal NQO1*2 was associated with lower maternal levels of adducts. Our findings suggest the need to reduce actual PM limits in MCMA. We did not observe a clear association between PM and/or adduct levels and neonate weight, length, body mass index, Apgar or Capurro score. Environ. Mol. Mutagen. 60:428-442, 2019. © 2019 Wiley Periodicals, Inc.

Elevation of isoprostanes in polycystic ovary syndrome and its relationship with cardiovascular risk factors.

PURPOSE: To evaluate the plasma level of 8-isoprostanes in women with polycystic ovary syndrome. To also investigate whether there is a relationship between 8-isoprostanes and several cardiovascular risk factors. METHODS: A total of 125 women with polycystic ovary syndrome and 169 healthy women were enrolled in this case-control study. 8-Isoprostanes and different parameters were measured in all subjects. Patients were evaluated for the presence of polycystic ovary syndrome according to the Rotterdam Consensus Conference criteria. RESULTS: 8-Isoprostanes levels were significantly higher in patients with polycystic ovary syndrome (138.4 ± 104.1 pg/mL) compared with control group (68.6 ± 34.3 pg/mL) (p < 0.001). The mean of triglycerides, lipid accumulation product, C-reactive protein, homocysteine, insulin, and homeostatic model assessment for insulin resistance were significantly higher in polycystic ovary syndrome patients with high 8-isoprostanes than those with normal 8-isoprostanes (p < 0.05). The Pearson correlation analyses showed that 8-isoprostanes levels in polycystic ovary syndrome group had a positive correlation with waist circumference, triglycerides, low-density lipoprotein cholesterol, apolipoprotein B, homocysteine, insulin, homeostatic model assessment for insulin resistance. CONCLUSIONS: Patients with polycystic ovary syndrome have higher 8-isoprostanes levels and it is associated with several cardiovascular risk factors.

Isoprostane in systemic sclerosis: A systematic review and meta-analysis.

OBJECTIVES: To further the knowledge of oxidative stress in systemic sclerosis (SSc), we performed a systematic review and meta-analysis on studies measuring isoprostane, a vasoactive agent deriving from arachidonic acid and implicated in the vasculopathy of SSc. METHODS: Systematic search following the PRISMA guidelines in PubMed and EMBASE between January-1990/December-2017 using the terms: oxidative stress, isoprostane, systemic sclerosis and scleroderma. RESULTS: After the screening process, 8 studies including 240 SSc patients and 192 controls were included in the systematic review and meta-analysis, 6 investigating urinary and 2 serum isoprostane: random effect meta-analysis revealed isoprostane overgeneration in SSc (p < .001) with wide heterogeneity (I2 = 75%). Subgroup analysis on urinary isoprostane favoured excess excretion in SSc (p = .009) with slightly lower heterogeneity (I2 = 67%); further subgroup analysis according to unit of measurement revealed no increased isoprostane excretion when expressed as pg/mg creatinine but increased when expressed as pmol/mmol creatinine (p = .05) with medium heterogeneity (I2 = 32%). Subgroup analysis on serum isoprostane favoured overproduction in SSc (p < .0001) with no heterogeneity. CONCLUSION: There is some evidence for isoprostane overgeneration in SSc that confirms the occurrence of oxidative stress in this setting: further prospective studies with specified outcomes are needed to evaluate the prognostic value of this functional biomarker.

Does Nox2 Overactivate in Children with Nonalcoholic Fatty Liver Disease?

It is unknown whether nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2) activation is early associated with endotoxemia and liver damage in nonalcoholic fatty liver disease (NAFLD). To address this issue, we evaluated Nox2 activation, oxidative stress, gut permeability, and lipopolysaccharide (LPS) serum levels in 67 children with biopsy-proven NAFLD and 73 controls. Compared with controls, NAFLD patients had higher Nox2 activity, isoprostane, zonulin, and LPS levels. Multivariate linear regression analysis showed that triglycerides, high-density lipoprotein (HDL), homeostatic model assessment-estimated insulin resistance (HOMA-IR), LPS, and isoprostanes were independently associated with Nox2-derivative peptide (sNox2-dp) levels. Within the NAFLD group, patients with nonalcoholic steatohepatitis (NASH) had significant higher levels of sNox2-dp, isoprostanes, LPS, triglycerides, HOMA-IR, fasting glucose and insulin, and lower HDL than those without NASH. Furthermore, sNox2-dp levels were linearly associated with the histological grading of steatosis, inflammation, ballooning, fibrosis, and NAFLD activity score. This study provides evidence that children with NAFLD have Nox2 overactivation compared with controls and significant association with the degree of liver damage. The close relationship between Nox2 and LPS serum levels leads to hypothesize a potential role for gut-derived LPS in eliciting systemic Nox2 activation.

Influence of Diosmin Treatment on the Level of Oxidative Stress Markers in Patients with Chronic Venous Insufficiency.

Oxidative stress plays an important role in the pathophysiology of many human disorders, while antioxidants prevent the development of various adverse symptoms. Diosmin is a natural flavonoid applied in vascular system disorders, especially in chronic venous insufficiency (CVI), and it plays a significant part in the alleviation of CVI symptoms. Due to antioxidant activity, it also has the ability to scavenge the oxygen free radicals and hence decreases the level of oxidative stress biomarkers, such as prostaglandins and their precursors-isoprostanes. In the study, the influence of diosmin treatment on the level of isoprostanes in plasma samples of patients suffering from CVI was examined. The qualitative analysis was performed using high-performance liquid chromatography with spectrometry detection (LC-MS). The statistically significant decrease of isoprostane content after 3 months of treatment was observed within the studied group; however, the most significant changes were observed in patients who smoke.

Experimental Woodsmoke Exposure During Exercise and Blood Oxidative Stress.

OBJECTIVES: The current laboratory study quantified blood oxidative stress to woodsmoke exposure. METHODS: Participants inhaled woodsmoke during three randomized crossover exercise trials (Clean Air [0 µg/m], Low Exposure [250 µg/m], and High Exposure [500 µg/m], Woodsmoke [particulate matter less than 2.5 µm, PM2.5]). Trolox equivalent antioxidant capacity (TEAC), uric acid (UA), 8-isoprostanes (8-ISO), lipid hydroperoxides (LOOH), protein carbonyls (PC), nitrotyrosine (3-NT), 8-isoprostane, and myeloperoxidase (MPO) were quantified in Pre, immediately Post, and 1- (1Hr) hour post blood samples. RESULTS: UA decreased following Low Exposure, while plasma TEAC levels increased Post and 1Hr. LOOH levels decreased 1Hr Post (High Exposure), while 8-Iso increased following both smoke trials. PC and MPO were unchanged following all trials, while 3-NT increased over Clean Air. CONCLUSION: Blood oxidative stress occurred largely independent of PM2.5 concentrations. Future studies should employ longer duration smoke and exercise combined with physiologic parameters.

Lipid peroxidation biomarkers for evaluating oxidative stress in equine neuroaxonal dystrophy.

BACKGROUND: Equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM) is a neurodegenerative disorder affecting genetically predisposed foals maintained on an α-tocopherol (α-TOH) deficient diet. Currently no antemortem diagnostic test for eNAD/EDM is available. HYPOTHESIS: Because α-TOH deficiency is associated with increased lipid peroxidation, it was hypothesized that F2 -isoprostanes (F2 IsoP), F4 -neuroprostanes (F4 NP) and oxysterols derived from free radical oxidation would be increased in the cerebrospinal fluid (CSF) and neural tissue of eNAD/EDM affected horses and could serve as potential biomarkers for disease. ANIMALS: Isoprostane Study A: 14 Quarter horse foals (10 healthy foals and 4 eNAD/EDM affected foals) at 1 and 6 months of age. Isoprostane Study B: 17 eNAD/EDM affected and 10 unaffected horses ≥ 1-4 years of age. Oxysterol study: eNAD/EDM affected (n = 14, serum; n = 11, CSF; n = 10, spinal cord [SC]) and unaffected horses 1-4 years of age (n = 12, serum; n = 10, CSF; n = 7, SC). PROCEDURES: Cerebrospinal fluid [F2 IsoP] and [F4 NP] were assessed using gas chromatography-negative ion chemical ionization mass spectrometry. Serum, CSF, and cervical SC [oxysterols] were quantified using high performance liquid chromatography mass spectrometry. Results were compared with respective α-TOH concentrations. RESULTS: Spinal cord [7-ketocholesterol], [7-hydroxycholesterol], and [7-keto-27-hydrocholesterol] were higher in eNAD/EDM horses whereas [24-ketocholesterol] was lower. No significant difference was found in CSF [F2 IsoP] and [F4 NP], serum [oxysterols] and CSF [oxysterols] between eNAD/EDM affected and unaffected horses. No correlation was found between [F2 IsoP], [F4 NP], or [oxysterols] and respective [α-TOH]. CONCLUSIONS AND CLINICAL IMPORTANCE: In the SC, targeted markers of cholesterol oxidation were significantly increased in horses with eNAD/EDM.