OBJECTIVE: The aim of the present study was the association between the relationship between Dietary Quality Index-International (DQI-I) and Healthy Eating Index (HEI) and the urinary levels of F2alpha-isoprostane (F2a-IP) and 8-hydroxy-2\'-deoxyguanosine (8-OHdG) was investigated as indicators of oxidative stress.
RESULTS: Based on HEI (low, moderate, and good), the diet quality of both groups was classified as moderate. In all participants, HEI (β=-0.29; P = 0.04) and DQI-I (β=-0.46; P = 0.005) were inversely associated with 8-OHdG. Furthermore, a negative correlation was found between HEI (mean β=-3.53; P = 0.04) and DQI-I (mean β=-5.53; P = 0.004) with F2a-IP. The quality of the footballers\' diet was higher than that of the control group. Following a high-quality diet, which is rich in antioxidants, is likely to effectively reduce oxidative stress.

BACKGROUND: There is limited evidence regarding the optimal time to commence parenteral nutrition (PN) in term and late preterm infants.
METHODS: Single-centre, non-blinded, exploratory randomised controlled trial.
METHODS: A level-3 neonatal unit in a stand-alone paediatric hospital.
METHODS: Infants born ≥34 weeks of gestation and ≤28 days, who needed PN. Eligible infants were randomised on day 1 or day 2 of admission.
METHODS: Early (day 1 or day 2 of admission, N=30) or late (day 6 of admission, N=30) PN.
METHODS: Plasma phenylalanine and F2-isoprostane levels on day 4 and day 8 of admission. Secondary outcomes were amino-acid and fatty-acid profiles on day 4 and day 8, and clinical outcomes.
RESULTS: The postnatal age at randomisation was similar between the groups (2.3 (SD 0.8) vs 2.3 (0.7) days, p=0.90). On day 4, phenylalanine levels in early-PN infants were higher than in late-PN (mean (SD) 62.9 (26.7) vs 45.5 (15.3) µmol/L; baseline-adjusted percentage difference 25.8% (95% CI 11.6% to 39.9%), p<0.001). There was no significant difference in phenylalanine levels between the two groups on day 8. There was no significant difference between the groups for F2-isoprostane levels on day 4 (early-PN mean (SD) 389 (176) vs late-PN 419 (291) pg/mL; baseline-adjusted percentage difference: -4.4% (95% CI -21.5% to 12.8%) p=0.62) and day 8 (mean (SD) 305 (125) vs 354 (113) pg/mL; adjusted mean percentage difference -16.1 (95% CI -34.1 to 1.9) p=0.09).Postnatal growth restriction for weight was less severe in the early-PN group (change in weight z-score from baseline to discharge: -0.6 (0.6) vs -1.0 (0.6); p=0.02). The incidence of hyperglycaemia was greater in the early-PN group (20/30 (66.7%) vs 11/30 (36.7%), p=0.02).
CONCLUSIONS: The timing of the commencement of PN did not seem to affect the degree of oxidative stress in critically ill term and late preterm infants. The effect of transiently high plasma phenylalanine with early PN on clinical outcomes requires further investigation.
BACKGROUND: ACTRN12620000324910.

As children spend up to 9 h a day in kindergarten, the main purpose of our study was to evaluate the effect of antioxidant-rich kindergarten meals on oxidative stress biomarkers (OSBs) in healthy children. In the randomized control trial with a follow-up, healthy 5-6-year-old children from six kindergartens were randomly divided into a prototype group (PG, n = 40) and a control group (CG, n = 17). PG followed a 2-week antioxidant-rich kindergarten meal plan (breakfast, lunch, and two snacks), and CG followed their standard kindergarten meal plans. Outside the kindergartens, participants ate as usual. We used a consecutive 7-day dietary record inside and outside the kindergarten and the national dietary assessment tool OPEN to assess the total dietary antioxidant capacity (dTAC) of the consumed foods. Malondialdehyde (MDA), 8-hydroxy-2-deoxyguanosine (8-OHdG), and four F2-isoprostane were measured in fasting urine on days 1 and 15. We also measured total antioxidant power (PAT) and hydroperoxides (d-ROMs) in fasting serum on day 15 and obtained the value of the oxidative stress index (OSI). We used a Welch two-sample t-test and multiple regression analysis to compare the prototype and control groups and a nonparametric Wilcoxon signed rank exact test to compare pre- and post-intervention results in urine. Antioxidant-rich kindergarten meals contributed to a significantly (p < 0.05) higher intake of dTAC in PG participants compared to standard meals in CG participants (8.6 vs. 2.8 mmol/day). We detected a negative correlation between dTAC intake and d-ROMs and between dTAC intake and OSI (r =  - 0.29, p = 0.043 and r =  - 0.31, p = 0.032, respectively). A significant decrease in urinary 8-iso-15-prostaglandin-F-2 alpha was detected in PG participants between days 1 and 15; however, no other intra-individual significant differences in urinary OSBs were found.  Conclusion: Antioxidant-rich food in kindergarten is warranted due to its potential health-protective effect. Additionally, we present original data on the average levels of urinary and serum OSBs in healthy 5-6-year-old children.  Trial registration: The study was registered at ClinicalTrials.gov, on February 5, 2020 ( https://clinicaltrials.gov/ct2/show/NCT04252105 ). What is Known: • Kindergartens are recognized as promising environments for public health measures. • A diet rich in antioxidants can reduce OSBs and, consequently, the risk of developing NCDs. What is New: • Antioxidant-rich kindergarten diet can ensure a protective intake of dTAC in children. • Original data on serum oxidative stress biomarkers (d-ROMs, PAT, and OSI) and urinary oxidative stress biomarkers (MDA, 8-OHdG, and F2 isoprostanes) in healthy 5-6-year-old children.

Isoprostanes (isoP) are formed during conditions of oxidative stress (OS) through the oxidation of cell membrane fatty acids. Different classes of isoP are formed depending on the fatty acid being oxidized but the biological activity of these molecules in innate immune cells is poorly understood. Thus, the objective of this study was to compare in vitro the effects of F2- and F3-isoP on neutrophil microbicidal functions. We isolated neutrophils from 6 dairy cows and incubated them for 8 h at various concentrations of F2- and F3-isoP. Then, microbicidal function was assessed in terms of phagocytosis, respiratory burst, myeloperoxidase activity, and extracellular trap formation. In vitro supplementation with F3-isoP enhanced microbicidal capabilities whereas supplementation with F2-isoP decreased or did not impact these microbe killing functions. Hence, favoring the production of F3- over F2-isoprostanes may be a strategy to augment neutrophils\' functional capacity during OS conditions. This should be tested in vivo.

Renal ischemia-reperfusion injury (IRI) is a critical health concern that aggravates the pathophysiology of acute kidney injury (AKI), leading to high mortality rates in intensive care units. Cardamonin is a natural compound with anti-inflammatory and antioxidant properties. The current study aimed to evaluate the renoprotective impact of cardamonin against AKI induced by renal IRI. Male rats (n=5 per group) were divided into four groups: the sham group underwent anesthesia and abdominal incision only; the control group experienced bilateral renal artery clamping for 30 minutes followed by 2 hours of reperfusion; the vehicle group received the cardamonin vehicle 30 minutes before ischemia induction; and the cardamonin group was administered 5 mg/kg of cardamonin 30 minutes before ischemia. Blood urea nitrogen (BUN) and creatinine were measured to assess the renal function. Tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β), interleukin-6 (IL-6), caspase 3, and F2-isoprostane were assessed in renal tissues. Kidney injury was examined using the hematoxylin and eosin stain method. Compared to the sham group, the control group exhibited significantly higher levels of BUN, creatinine, TNF-α, IL-1β, IL-6, F2-isoprostane, and caspase 3 in renal tissues, along with severe kidney injury as evidenced by histological analysis. Compared to the control group, pretreatment with cardamonin resulted in a significant reduction in these biomarkers and alleviated renal damage. Cardamonin had renoprotective effects against renal ischemia and reperfusion injury via modulating inflammation, oxidative stress, and apoptosis pathways.

Dioxin-like pollutants (DLPs), such as polychlorinated biphenyl 126 (PCB 126), are synthetic chemicals classified as persistent organic pollutants. They accumulate in adipose tissue and have been linked to cardiometabolic disorders, including fatty liver disease. The toxicity of these compounds is associated with activation of the aryl hydrocarbon receptor (Ahr), leading to the induction of phase I metabolizing enzyme cytochrome P4501a1 (Cyp1a1) and the subsequent production of reactive oxygen species (ROS). Recent research has shown that DLPs can also induce the xenobiotic detoxification enzyme flavin-containing monooxygenase 3 (FMO3), which plays a role in metabolic homeostasis. We hypothesized whether genetic deletion of Fmo3 could protect mice, particularly in the liver, where Fmo3 is most inducible, against PCB 126 toxicity. To test this hypothesis, male C57BL/6 wild-type (WT) mice and Fmo3 knockout (Fmo3 KO) mice were exposed to PCB 126 or vehicle (safflower oil) during a 12-week study, at weeks 2 and 4. Various analyses were performed, including hepatic histology, RNA-sequencing, and quantitation of PCB 126 and F2-isoprostane concentrations. The results showed that PCB 126 exposure caused macro and microvesicular fat deposition in WT mice, but this macrovesicular fatty change was absent in Fmo3 KO mice. Moreover, at the pathway level, the hepatic oxidative stress response was significantly different between the two genotypes, with the induction of specific genes observed only in WT mice. Notably, the most abundant F2-isoprostane, 8-iso-15-keto PGE2, increased in WT mice in response to PCB 126 exposure. The study\'s findings also demonstrated that hepatic tissue concentrations of PCB 126 were higher in WT mice compared to Fmo3 KO mice. In summary, the absence of FMO3 in mice led to a distinctive response to dioxin-like pollutant exposure in the liver, likely due to alterations in lipid metabolism and storage, underscoring the complex interplay of genetic factors in the response to environmental toxins.

Inflammation and oxidative stress are critical to pregnancy, but most human study has focused on downstream, non-causal indicators. Oxylipins are lipid mediators of inflammation and oxidative stress that act through many biological pathways. Our aim was to characterize predictors of circulating oxylipin concentrations based on maternal characteristics.
Our study was conducted among 901 singleton pregnancies in the LIFECODES Fetal Growth Study, a nested case-cohort with recruitment from 2007 to 2018. We measured a targeted panel of oxylipins in early pregnancy plasma and urine samples from several biosynthetic pathways, defined by the polyunsaturated fatty acid (PUFA) precursor and enzyme group. We evaluated levels across predictors, including characteristics of participants\' pregnancy, socioeconomic determinants, and obstetric and medical history.
Current pregnancy and sociodemographic characteristics were the most important predictors of circulating oxylipins concentrations. Plasma oxylipins were lower and urinary oxylipins higher for participants with a later gestational age at sampling (13-23 weeks), higher prepregnancy BMI (obesity class I, II, or III), Black or Hispanic race and ethnicity, and lower socioeconomic status (younger age, lower education, and uninsured). For example, compared to those with normal or underweight prepregnancy BMI, participants with class III prepregnancy obesity had 45-46% lower plasma epoxy-eicosatrienoic acids, the anti-inflammatory oxylipins produced from arachidonic acid (AA) by cytochrome P450, and had 81% higher urinary 15-series F2-isoprostanes, an indicator of oxidative stress produced from non-enzymatic AA oxidation. Similarly, in urine, Black participants had 92% higher prostaglandin E2 metabolite, a pro-inflammatory oxylipin, and 41% higher 5-series F2-isoprostane, an oxidative stress indicator.
In this large pregnancy study, we found that circulating levels of oxylipins were different for participants of lower socioeconomic status or of a systematically marginalized racial and ethnic groups. Given associations differed along biosynthetic pathways, results provide insight into etiologic links between maternal predictors and inflammation and oxidative stress.

UDP-glucuronosyltransferases (UGTs) catalyze the conjugation of glucuronic acid with endogenous and exogenous lipophilic small molecules to facilitate their inactivation and excretion from the body. This represents approximately 35 % of all phase II metabolic transformations. Fatty acids and their oxidized eicosanoid derivatives can be metabolized by UGTs. F2-isoprostanes (F2-IsoPs) are eicosanoids formed from the free radical oxidation of arachidonic acid. These molecules are potent vasoconstrictors and are widely used as biomarkers of endogenous oxidative damage. An increasing body of evidence demonstrates the efficacy of measuring the β-oxidation metabolites of F2-IsoPs rather than the unmetabolized F2-IsoPs to quantify oxidative damage in certain settings. Yet, the metabolism of F2-IsoPs is incompletely understood. This study sought to identify and characterize novel phase II metabolites of 15-F2t-IsoP and 5-epi-5-F2t-IsoP, two abundantly produced F2-IsoPs, in human liver microsomes (HLM). Utilizing liquid chromatography-mass spectrometry, we demonstrated that glucuronide conjugates are the major metabolites of these F2-IsoPs in HLM. Further, we showed that these molecules are metabolized by specific UGT isoforms. 15-F2t-IsoP is metabolized by UGT1A3, 1A9, and 2B7, while 5-epi-5-F2t-IsoP is metabolized by UGT1A7, 1A9, and 2B7. We identified, for the first time, the formation of intact glucuronide F2-IsoPs in human urine and showed that F2-IsoP glucuronidation is reduced in people supplemented with eicosapentaenoic and docosahexaenoic acids for 12 weeks. These studies demonstrate that endogenous F2-IsoP levels can be modified by factors other than redox mechanisms.

OBJECTIVE: We assessed the cross-sectional association between healthy dietary patterns [alternate Mediterranean diet (aMED), Dietary Approaches to Stop Hypertension (DASH), alternative Healthy Eating Index (aHEI), and Healthy Eating Index 2015 (HEI-2015)] and urinary biomarkers of oxidative stress.
METHODS: Between 2003 and 2009, the Sister Study enrolled 50,884 breast cancer-free US women aged 35 to 74 (non-Hispanic White, 83.7%). Data were analyzed for 844 premenopausal and 454 postmenopausal women who had urine samples analyzed for F2-isoprostanes and non-missing covariate data. Food frequency questionnaire responses were used to calculate dietary pattern scores. Concentrations of 8-iso-prostaglandin F2α (8-iso-PGF2α) and its metabolite (8-iso-PGF2α-M) were measured in urine samples by GC/MS for premenopausal women and LC/MS for postmenopausal women. Multivariable linear regression models were used to estimate associations between aMED, DASH, aHEI, and HEI-2015 and urinary F2-isoprostanes by menopausal status. Effect modification by sociodemographic, lifestyle, and clinical characteristics was also evaluated.
RESULTS: Among premenopausal women, the four dietary indices were inversely associated with 8-iso-PGF2α (aMED βQ4vsQ1: - 0.17, 95% CI - 0.27, - 0.08; DASH βQ4vsQ1: - 0.18, 95% CI - 0.28, - 0.08; aHEI βQ4vsQ1: - 0.20, 95% CI - 0.30, - 0.10; HEI-2015 βQ4vsQ1: - 0.19, 95% CI - 0.29, - 0.10). In contrast, inverse associations with 8-iso-PGF2α-M were found for the continuous aMED, aHEI, and HEI-2015. Associations between dietary indices and 8-iso-PGF2α were generally stronger among younger women, women with lower income, and women with higher BMI. Similar results were observed among postmenopausal women, though only the continuous DASH and aHEI models were statistically significant.
CONCLUSIONS: Healthy dietary patterns were associated with lower levels of oxidative stress.

Theoretically, some metabolic traits may predispose older individuals to weight loss during aging, leading to increased all-cause mortality and many serious health issues. Biomarkers to robustly predict progressive weight loss during aging are, however, lacking. We prospectively assessed if urinary levels of F2-isoprostanes and their peroxisomal β-oxidation metabolite, 2,3-dinor-5,6-dihydro-15-F2t-isoprostane (F2-IsoP-M), were associated with subsequent weight loss in middle-aged and older women.
Included in the analysis were 2,066 women aged 40-70 years, a subset of a prospective cohort study. F2-isoprostanes (F2-IsoPs) and its β-oxidation metabolite, F2-IsoP-M, were measured in urine using gas chromatography-mass spectrometry. Measurements of anthropometry and exposures to major determinants of body weight were performed at baseline and repeated thrice over 15-year follow-up. The longitudinal associations of F2-IsoP-M and the F2-IsoP-M to its parent compound, F2-IsoP, ratio (MPR) with repeatedly measured weight changes were examined using linear mixed-effect models.
After adjusting for time-varying covariates: energy intake, physical activity, and comorbidity index, among others, levels of F2-IsoP-M and the MPR were both inversely associated with percentage of weight change. Weight in the highest quartile of these two biomarkers was 1.33% (95% CI = -2.41, -0.24) and 1.09% (95% CI = -2.16, -0.02) lower than those in the lowest quartile group, with p for trend of 0.01 and 0.03, respectively. The inverse association was consistently seen across follow-up periods, although appearing stronger with prolonged follow-up. There was no association between the parent compound, F2-IsoPs, and weight change.
This study demonstrates the first piece of evidence to associate F2-IsoP metabolism, peroxisomal β-oxidation, with weight loss in older women. Further investigations into the role of lipid peroxidation and peroxisomal β-oxidation in weight change among older individuals are warranted.