Biomarkers of oxidative stress study II: are oxidation products of lipids, proteins, and DNA markers of CCl4 poisoning?

Urolithin D: A promising metabolite of ellagitannin in combatting oxidative stress

The objective of this research is to examine the function of urolithin D (UroD, 3,4,8,9-tetrahydroxy-6H-benzo[c]chromen-6-one), a metabolite obtained from ellagitannins, in the mitigation of oxidative stress. The research is based on estimating the mechanisms through which UroD acts as an antioxidant under physiological conditions, emphasizing standard antioxidant mechanisms such as formal Hydrogen Aatom Transfer (f-HAT), Radical Adduct Formation (RAF)/Radical Coupling Formation (RCF), and Single Electron Transfer followed by Proton Transfer (SET-PT). This study utilised advanced quantum mechanical techniques, specifically density functional theory (DFT) and the Quantum Mechanics-based test for Overall free Radical Scavenging activity (QM-ORSA) methodology, to assess the thermodynamic and kinetic parameters of UroD in the presence of reactive radical species HOO•, CH3OO• and CCl3OO•. The estimated overall rate constants (koverall) indicate a reactivity order of CCl3OO• (koverall = 2.06 × 1010 M-1s-1) > HOO• (koverall = 2.59 × 109 M-1s-1) > CH3OO• (koverall = 1.89 × 109 M-1s-1). The examination of the relative proportions of products (%) indicates that UroD exhibits antiradical action primarily through all examined mechanisms, with the predominant involvement of mononion and dianion acid-base species. In addition to its capacity to directly counteract ROS, UroD can restore oxidative DNA damage, specifically targeting oxidative byproducts commonly associated with 2-deoxyguanosine (2 dG), which are susceptible to oxidative stress. The UroD regenerates G-centered radical cations (2 dG•+) through the SET mechanism, C-centered radicals (2 dG•) in the sugar moiety through f-HAT, and repairs i-OH-2dG lesions through sequential hydrogen atom transfer dehydration (SHATD). Additionally, the radical products formed during antioxidant action can be regenerated in the presence of O2•- into anionic species, which are subsequently protonated into neutral species that can re-engage in antioxidant activity. These findings underscore the efficiency of UroD in scavenging free radicals and suggest its potential role in preserving cellular integrity and protecting against oxidative stress-related diseases.

Simultaneous quantification of four urinary biomarkers related to oxidative stress using UHPLC-QqQ-MS/MS

Oxidative stress biomarkers have been associated with both acute and chronic health outcomes. However, traditional methods analyze different biomarkers separately, resulting in complex sample preparation, high sample consumption, lengthy processing time, and limited comparability. In this study, we presented a newly developed and validated method for the simultaneous determination of oxidative stress from multiple perspectives (DNA, lipids, and antioxidants). Using a one-step solid-phase extraction and ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS), we measured four oxidative stress related biomarkers in urine simultaneously, within a run time of only 12 min. These biomarkers included 8-hydroxy-2'-deoxyguanosine (8-OHdG), 6-sulfatoxymelatonin (aMT6s), 8-isoprostaglandin-F2α (8-isoPGF2α), and 11-dehydro thromboxane B2 (11-DH-TXB2). The calibration curves showed wide linear ranges (0.4-800 ng/mL for 8-OHdG, 0.2-600 ng/mL for aMT6s, 0.4-600 ng/mL for 8-isoPGF2α, and 0.4-600 ng/mL for 11-DH-TXB2), with r2 values above 0.9932 for all analytes. The method demonstrated excellent sensitivity, with detection limits below 0.12 ng/mL, and good precision, with intra- and inter-day coefficients of variation ranging from 1.2 % to 14.4 %. We applied this method to urine samples from two populations living at different altitudes and found significantly higher levels of both 8-OHdG and 11-DH-TXB2 in the high-altitude group, likely due to hypobaric hypoxia. In the future, this new method could be applied in large-scale epidemiological studies to investigate biological mechanisms of oxidative stress in health risks or for clinical diagnosis.

C-reactive protein attenuates CCl4-induced acute liver injury by regulating complement system activation

Acute liver injury is liver dysfunction caused by multiple factors without any pre-existing liver disease. C-reactive protein (CRP) is an acute-phase protein produced by hepatocytes, serving as a marker of inflammation and tissue damage. However, its role in CCl4-induced acute liver injury has not been elucidated. Here, we report that CRP protects against CCl4-induced acute liver injury by regulating complement activation. CRP knockout exacerbates CCl4-induced acute liver injury in mice and rats, markedly enhances tissue damage, and reduces survival. Administration of exogenous CRP to CRP-knockout mice rescues the CCl4-induced liver injury phenotype. The protective effect of CRP is independent of its cellular receptor FcγR2b and early metabolic pathways. Instead, CRP suppresses the late-phase amplification of inflammation by inhibiting terminal complement pathway overactivation in injured hepatocytes via factor H recruitment. In complement C3 knockout (C3-/-) mice, the protective effect of CRP against CCl4-induced acute liver injury is lost. These results suggest that CRP can alleviate CCl4-induced acute liver injury by regulating the complement pathway, providing a theoretical basis for CRP's potential involvement and regulation of disease severity.

Lipid peroxidation and colorectal cancer risk: a time-varying relationship

Importance

We recently observed an inverse and time-dependent association between systemic oxidative stress (OxS), measured by urinary biomarkers of nucleic acid oxidation, and colorectal cancer (CRC) risk. Further investigations into other types of OxS markers are warranted.

Objective

To extend the investigation into systemic lipid peroxidation and CRC risk.

Design Setting and Participants

Utilizing a nested case-control design, this study's primary analysis was performed in two large prospective cohorts in Shanghai, China, and replicated in an independent cohort in the US.

Exposures

Systemic lipid peroxidation was assessed by urinary F 2 -isoprostanes (F 2 -IsoPs) using UPLC-MS/MS assays.

Main Outcomes and Measures

During 15.1-year follow-up in the Shanghai cohorts, 1938 incident CRC cases were identified and matched to one control each through incidence-density sampling. In the US cohort, 285 incident CRC cases were included, each matched to two controls. Odds ratios (ORs) for CRC were calculated using multivariable conditional logistic regression models.

Results

Elevated levels of urinary 5-F 2t -IsoP (5-iPF 2α -VI), a major isomer of F 2 -IsoPs induced solely by free radicals, were associated with reduced risk of CRC in the Shanghai cohorts. This finding was replicated in the US cohort. Moreover, this inverse association was time-dependent, manifesting only in the later years of cancer development. Multivariable-adjusted ORs (95% CI) for CRC diagnosed within 5 years of enrollment at the 10th and 90th percentiles of 5-F 2t -IsoP levels, relative to the median, were 1.57 (1.26-1.96) and 0.61 (0.42-0.89), respectively, indicating a 2.2-fold difference in risk between the two groups. A stronger association was observed when using the composite index of DNA, RNA and lipid OxS markers, showing a 3.9-fold difference in risk between the two groups. No significant association was found for CRC diagnosed beyond 5 years of enrollment.

Conclusions

This study provides new evidence that systemic OxS is inversely and time-dependently associated with CRC risk in humans.

Key Points

Question: Is the time-dependent relationship between oxidative stress and tumorigenesis observed at the cellular level in experimental models also present at the systemic level in a population-based setting?Findings: Elevated systemic lipid peroxidation, measured by urinary F 2 -isoprostanes, was associated with a reduced risk of colorectal cancer (CRC) in two large prospective cohort studies in Shanghai, China, which was replicated in an independent cohort in the United States. This association varied over time, showing a stronger effect as cancer advanced. Meaning: This study provides new evidence that systemic oxidative stress is inversely and time-dependently associated with CRC risk in humans.

Time-dependent relationship between urinary biomarkers of nucleic acid oxidation and colorectal cancer risk

PURPOSE

Randomized controlled trials have failed to validate that neutralizing oxidative stress (OxS) through antioxidant supplementation reduces cancer risk. This study aims to prospectively investigate whether the relationship between systemic OxS and colorectal cancer (CRC) risk changes over the course of cancer development.

METHODS

This study utilized a nested case-control design in two Shanghai cohorts for primary analysis and one US cohort for replication analysis. During a median follow-up of 15.1 years in the Shanghai cohorts, 1938 incident CRC cases were identified and matched to one control each. In the US cohort, 285 incident CRC cases were included with two matched controls per case. Systemic OxS was assessed by urinary markers of DNA oxidation (8-oxo-7,8-dihydro-2'-deoxyguanosine [8-oxo-dG]) and RNA oxidation (7,8-dihydro-8-oxo-guanosine [8-oxo-Guo]) using UPLC-MS/MS assays. Multivariable-adjusted odds ratios (ORs) for CRC risk were calculated.

RESULTS

After adjusting for potential confounders, we observed an inversion association between OxS markers and CRC risk in the Shanghai cohorts, which was independently replicated in the US cohort. Moreover, the inverse association was time-dependent, manifesting only for CRC cases diagnosed within 5 years of enrollment. ORs (95% CI) for CRC at the 10th and 90th percentiles of 8-oxo-dG levels, relative to the median, were 1.87 (1.39 to 2.53) and 0.48 (0.37 to 0.63), respectively, demonstrating an approximate 4-fold difference in risk between the two groups, with P for overall association of < 0.001. A similar pattern was observed for 8-oxo-Guo. No significant association was found for CRC diagnosed beyond 5 years of enrollment.

CONCLUSION

This novel finding of an inverse and time-dependent relationship between systemic OxS and CRC risk, if further confirmed, may provide a new perspective for revisiting redox-based chemoprevention.

CONTEXT

Background: Almost all large randomized controlled trials have failed to validate the hypothesis that neutralizing oxidative stress through antioxidant supplementation can lower cancer risk, which has puzzled the public and researchers for decades.Key Findings: A reduced risk for colorectal cancer (CRC) with increasing systemic oxidative stress, measured by two urinary biomarkers of DNA and RNA oxidation, was observed in two large prospective cohort studies in Shanghai, China, and was replicated in an independent cohort in the United States. This association was time-dependent, with the inverse relationship strengthening as the biomarker assessment neared the time of CRC diagnosis.Relevance: Our study, for the first time, suggests an inverse and time-dependent relationship between systemic oxidative stress and CRC development, which, if further confirmed, may provide a new perspective for revisiting redox-based chemoprevention.

Nonenzymatic Oxidized Polyunsaturated Fatty Acid Products in Human Plasma and Urine Samples by LC-QTOF-MS/MS

Oxidative stress induces autooxidation of polyunsaturated fatty acids, producing numerous isoprostanoids and isofuranoids. These oxidized products are measurable in human plasma and urine and serve as oxidative stress biomarkers for chronic diseases. This chapter details the preparation and measurement of α-linolenic acid-derived phytoprostanes and phytofurans in human samples using liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-QToF-MS/MS).

Metabolites derived from radical oxidation of PUFA: NEO-PUFAs, promising molecules for health?

Oxidative stress plays a critical role in numerous pathological processes. Under these stress conditions, the free radical-catalyzed lipid peroxidation generates in vivo a large number of key products that are involved in many physiological and pathophysiological processes. Among these products are neuroprostanes, which arise from the peroxidation of docosahexaenoic acid (DHA), and isoprostanes, resulting from arachidonic acid (AA) and eicosapentaenoic acid (EPA) through the same peroxidation process. These non-enzymatic oxygenated metabolites newly appointed NEO-PUFAs have gained recognition as reliable markers of oxidative stress in neurogenerative and cardiovascular diseases. Moreover, some of them display a wide range of biological activities. The ability to detect and measure these metabolites offers precious insights into the mechanisms of oxidative damage and holds potential therapeutic implications for various health conditions, including neurodegenerative diseases. This review focuses on the role of neuroprostanes as biomarkers for oxidative stress and related diseases, highlighting their potential applications in medical research and treatment.

Intraoperative Oxygen Treatment, Oxidative Stress, and Organ Injury Following Cardiac Surgery: A Randomized Clinical Trial

Importance

Liberal oxygen (hyperoxia) is commonly administered to patients during surgery, and oxygenation is known to impact mechanisms of perioperative organ injury.

Objective

To evaluate the effect of intraoperative hyperoxia compared to maintaining normoxia on oxidative stress, kidney injury, and other organ dysfunctions after cardiac surgery.

Design, Setting, and Participants

This was a participant- and assessor-blinded, randomized clinical trial conducted from April 2016 to October 2020 with 1 year of follow-up at a single tertiary care medical center. Adult patients (>18 years) presenting for elective open cardiac surgery without preoperative oxygen requirement, acute coronary syndrome, carotid stenosis, or dialysis were included. Of 3919 patients assessed, 2501 were considered eligible and 213 provided consent. Of these, 12 were excluded prior to randomization and 1 following randomization whose surgery was cancelled, leaving 100 participants in each group.

Interventions

Participants were randomly assigned to hyperoxia (1.00 fraction of inspired oxygen [FiO2]) or normoxia (minimum FiO2 to maintain oxygen saturation 95%-97%) throughout surgery.

Main Outcomes and Measures

Participants were assessed for oxidative stress by measuring F2-isoprostanes and isofurans, for acute kidney injury (AKI), and for delirium, myocardial injury, atrial fibrillation, and additional secondary outcomes. Participants were monitored for 1 year following surgery.

Results

Two hundred participants were studied (median [IQR] age, 66 [59-72] years; 140 male and 60 female; 82 [41.0%] with diabetes). F2-isoprostanes and isofurans (primary mechanistic end point) increased on average throughout surgery, from a median (IQR) of 73.3 (53.1-101.1) pg/mL at baseline to a peak of 85.5 (64.0-109.8) pg/mL at admission to the intensive care unit and were 9.2 pg/mL (95% CI, 1.0-17.4; P = .03) higher during surgery in patients assigned to hyperoxia. Median (IQR) change in serum creatinine (primary clinical end point) from baseline to postoperative day 2 was 0.01 mg/dL (-0.12 to 0.19) in participants assigned hyperoxia and -0.01 mg/dL (-0.16 to 0.19) in those assigned normoxia (median difference, 0.03; 95% CI, -0.04 to 0.10; P = .45). AKI occurred in 21 participants (21%) in each group. Intraoperative oxygen treatment did not affect additional acute organ injuries, safety events, or kidney, neuropsychological, and functional outcomes at 1 year.

Conclusions

Among adults receiving cardiac surgery, intraoperative hyperoxia increased intraoperative oxidative stress compared to normoxia but did not affect kidney injury or additional measurements of organ injury including delirium, myocardial injury, and atrial fibrillation.

Trial Registration

ClinicalTrials.gov Identifier: NCT02361944.

Neuroprotective Actions of Hydrogen Sulfide-Releasing Compounds in Isolated Bovine Retinae

Background: We have evidence that hydrogen sulfide (H2S)-releasing compounds can reduce intraocular pressure in normotensive and glaucomatous rabbits by increasing the aqueous humor (AH) outflow through the trabecular meshwork. Since H2S has been reported to possess neuroprotective actions, the prevention of retinal ganglion cell loss is an important strategy in the pharmacotherapy of glaucoma. Consequently, the present study aimed to investigate the neuroprotective actions of H2S-releasing compounds against hydrogen peroxide (H2O2)-induced oxidative stress in an isolated bovine retina. Materials and Methods: The isolated neural retinae were pretreated with a substrate for H2S biosynthesis called L-cysteine, with the fast H2S-releasing compound sodium hydrosulfide, and with a mitochondrial-targeting H2S-releasing compound, AP123, for thirty minutes before a 30-min oxidative insult with H2O2 (100 µM). Lipid peroxidation was assessed via an enzyme immunoassay by measuring the stable oxidative stress marker, 8-epi PGF2α (8-isoprostane), levels in the retinal tissues. To determine the role of endogenous H2S, studies were performed using the following biosynthesis enzyme inhibitors: aminooxyacetic acid (AOAA, 30 µM); a cystathione-β-synthase/cystathionine-γ-lyase (CBS/CSE) inhibitor, α-ketobutyric acid (KBA, 1 mM); and a 3-mercaptopyruvate-s-sulfurtransferase (3-MST) inhibitor, in the absence and presence of H2S-releasing compounds. Results: Exposure of the isolated retinas to H2O2 produced a time-dependent (10-40 min) and concentration-dependent (30-300 µM) increase in the 8-isoprostane levels when compared to the untreated tissues. L-cysteine (10 nM-1 µM) and NaHS (30 -100 µM) significantly (p < 0.001; n = 12) prevented H2O2-induced oxidative damage in a concentration-dependent manner. Furthermore, AP123 (100 nM-1 µM) attenuated oxidative H2O2 damage resulted in an approximated 60% reduction in 8-isoprostane levels compared to the tissues treated with H2O2 alone. While AOAA (30 µM) and KBA (1 mM) did not affect the L-cysteine evoked attenuation of H2O2-induced oxidative stress, KBA reversed the antioxidant responses caused by AP123. Conclusions: In conclusion, various forms of H2S-releasing compounds and the substrate, L-cysteine, can prevent H2O2-induced lipid peroxidation in an isolated bovine retina.

Brain mitochondrial damage attenuation by quercetin and N-acetyl cysteine: peripheral and central antiemetic effects

Nausea serves as a protective mechanism in organisms to prevent excessive consumption of toxic substances. Due to the adverse effects of chemical anti-nausea drugs, there is a growing interest in using herbal remedies and natural antioxidants. In this study, we evaluated the neuroprotective effects of quercetin (QU) and N-acetylcysteine (NAC) against oxidative damage induced by nausea. Emesis was induced in chickens using ipecac and copper sulfate (600 and 60 mg/kg, orally, respectively). QU and NAC (with doses of 50, 100, 200 mg/kg), and their combination were administered, along with a standard therapy (metoclopramide; MET 2 mg/kg) for one-time. Mitochondrial function, lipid peroxidation (LPO), protein carbonyl (PC), glutathione level (GSH), and reactive oxygen species (ROS) as oxidative damage biomarkers were evaluated in the chicken's brain mitochondria. QU and NAC significantly reduced emesis induced by copper sulfate and ipecac compared to the control group (P < 0.001). Significant differences in oxidative damage were observed in the groups received of copper sulfate and ipecac compared with control group. Levels of LPO, ROS, and PC were significantly decreased after the administration of QU and NAC in emesis induced by copper sulfate and ipecac. While, mitochondrial function and GSH levels were increased after the administration of QU and NAC. Combination therapy with QU and NAC yielded the most effective results. This study suggests that QU and NAC possess antiemetic effects through both peripheral and central mechanisms and exhibit neuroprotective effects against oxidative brain damage induced by emesis by increasing plasma antioxidants or scavenging free radicals.

Response to chronic crowding stress in shy and bold behavioral groups of male and female zebrafish

In recent years, there has been a burgeoning interest in exploring the nuances of animal stress physiology, particularly in relation to parameters such as sex and behavioral phenotype-dependent variations, which is crucial for understanding phenotypic variation and its role in evolutionary selection. However, a significant dearth remains in how chronic stressors affect organismal stress physiology concerning the aforesaid parameters. This void is even wider pertaining to the response of peripheral tissues, such as the skin, the organ with the highest surface contact area with the environment. Hence, we behaviorally grouped the zebrafishes based on their boldness and the body condition, whole body cortisol response, along with examining the transcriptional response, global DNA methylome, and oxidative DNA damage in the skin upon chronic crowding. Upon baseline conditions, clear distinction between bold and shy phenotypes was found, particularly in males. The boldness index score distribution exhibited greater uniformity in males than in females. Regarding the body condition response to chronic crowding, shy males showed a significant relative decline compared with their bold counterparts, while this trend did not hold true for females. qPCR data revealed distinctive expression patterns in key genes that play critical roles in cellular processes such as stress-mediated gene regulation, immune response, oxidative stress protection, and maintenance of genomic integrity through epigenetic modifications across behavioral phenotypes and sexes under both with and without chronic crowding stress. Global DNA methylation levels significantly declined only in chronically crowded shy males, and sex/behavioral phenotype-dependent trends in oxidative DNA damage were identified.NEW & NOTEWORTHY This paper analyzes the response of zebrafish to crowding stress through a new approach focused on the peripheral response dynamics of the skin, the main mucosal tissue, and involving sex and behavioral phenotype influences. Shy males showed significant distress as observed by body condition, physiological and transcriptional response, and global DNA methylation. Nuances in stress response across behavioral phenotypes and sex indicate a genetic and behavioral specificity and further inherent epigenetic regulatory dimension.

Beneficial effects of a combined lifestyle intervention for older people in a long-term-care facility on redox balance and endothelial function

Objective

It has recently been highlighted how a short healthy life-style program (LSP) can improve the functional outcomes of older people admitted to a Long-Term Care (LTC) facility. Although it is known that life-style medicine-based interventions can exert anti-aging effects through the modulation of oxidative stress and mitochondrial function, the mechanisms underlying the aforementioned effects have not been clarified, yet. For this reason, in this study, the outcomes were focused on the investigation of the possible mechanisms underlying the benefits of a short LSP in older people. This was achieved by examining circulating markers of oxidative stress and immunosenescence, such as Tymosin β (Tβ4), before and after LSP and the effects of plasma of older people undergone or not LSP on endothelial cells.

Methods

Fifty-four older people were divided into two groups (n = 27 each): subjects undergoing LSP and subjects not undergoing LSP (control). The LSP consisted of a combination of caloric restriction, physical activity, and psychological intervention and lasted 3 months. Plasma samples were taken before (T0) and after LSP (T1) and were used to measure thiobarbituric acid reactive substances (TBARS), 8-hydroxy-2-deoxyguanosine (8OHdG), 8-Isoprostanes (IsoP), glutathione (GSH), superoxide dismutase (SOD) activity and Tβ4. In addition, plasma was used to stimulate human vascular endothelial cells (HUVEC), which were examined for cell viability, mitochondrial membrane potential, reactive oxygen species (ROS) and mitochondrial ROS (MitoROS) release.

Results

At T1, in LSP group we did not detect the increase of plasma TBARS and IsoP, which was observed in control. Also, plasma levels of 8OHdG were lower in LSP group vs control. In addition, LSP group only showed an increase of plasma GSH and SOD activity. Moreover, plasma levels of Tβ4 were more preserved in LSP group. Finally, at T1, in HUVEC treated with plasma from LSP group only we found an increase of the mitochondrial membrane potential and a reduction of ROS and MitoROS release in comparison with T0.

Conclusions

The results of this study showed that a short LSP in older persons exerts antiaging effects by modulating oxidative stress also at cellular levels. Implications of those findings could be related to both prognostic and therapeutic strategies, which could be pursued as antiaging methods.

Oxylipin profiling for clinical research: Current status and future perspectives

Oxylipins are potent lipid mediators with increasing interest in clinical research. They are usually measured in systemic circulation and can provide a wealth of information regarding key biological processes such as inflammation, vascular tone, or blood coagulation. Although procedures still require harmonization to generate comparable oxylipin datasets, performing comprehensive profiling of circulating oxylipins in large studies is feasible and no longer restricted by technical barriers. However, it is essential to improve and facilitate the biological interpretation of complex oxylipin profiles to truly leverage their potential in clinical research. This requires regular updating of our knowledge about the metabolism and the mode of action of oxylipins, and consideration of all factors that may influence circulating oxylipin profiles independently of the studied disease or condition. This review aims to provide the readers with updated and necessary information regarding oxylipin metabolism, their different forms in systemic circulation, the current limitations in deducing oxylipin cellular effects from in vitro bioactivity studies, the biological and technical confounding factors needed to consider for a proper interpretation of oxylipin profiles.

Seeing beyond words: Visualizing autism spectrum disorder biomarker insights

Objective

This study employs bibliometric and visual analysis to elucidate global research trends in Autism Spectrum Disorder (ASD) biomarkers, identify critical research focal points, and discuss the potential integration of diverse biomarker modalities for precise ASD assessment.

Methods

A comprehensive bibliometric analysis was conducted using data from the Web of Science Core Collection database until December 31, 2022. Visualization tools, including R, VOSviewer, CiteSpace, and gCLUTO, were utilized to examine collaborative networks, co-citation patterns, and keyword associations among countries, institutions, authors, journals, documents, and keywords.

Results

ASD biomarker research emerged in 2004, accumulating a corpus of 4348 documents by December 31, 2022. The United States, with 1574 publications and an H-index of 213, emerged as the most prolific and influential country. The University of California, Davis, contributed significantly with 346 publications and an H-index of 69, making it the leading institution. Concerning journals, the Journal of Autism and Developmental Disorders, Autism Research, and PLOS ONE were the top three publishers of ASD biomarker-related articles among a total of 1140 academic journals. Co-citation and keyword analyses revealed research hotspots in genetics, imaging, oxidative stress, neuroinflammation, gut microbiota, and eye tracking. Emerging topics included "DNA methylation," "eye tracking," "metabolomics," and "resting-state fMRI."

Conclusion

The field of ASD biomarker research is dynamically evolving. Future endeavors should prioritize individual stratification, methodological standardization, the harmonious integration of biomarker modalities, and longitudinal studies to advance the precision of ASD diagnosis and treatment.

Zinc about it - zinc and calf immunity

Micronutrients, such as vitamins and trace minerals, are critical for supporting growth, performance, health and maintaining redox balance. Zinc (Zn), an essential micronutrient, aids the functioning of innate and adaptive immune cells. This scoping review aims to assemble and evaluate the evidence available for the role of Zn within calf immunity. Relevant literature was identified within Web of Science, PubMed, and CABI using search terms specific to the major innate and adaptive immune cell populations. There was no evidence that Zn supplementation altered neutrophil, natural killer cell, or T-cell functions. However, there was limited evidence to support Zn supplementation with reduced monocyte numbers, but there was no evidence to associate the monocytopenia with improvements in monocyte function. There is moderate evidence to suggest that Zn supplementation was beneficial for maintaining epithelial barriers of integumental and mucosal surfaces. The evidence supports supplementation above the current industry recommendations for improving immunoglobulin (Ig) production, with the strongest results being observed for IgG and IgM. Moreover, Zn supplementation was associated with reduced proinflammatory cytokine production, which may reduce inflammation-associated hypophagia and warrants further investigation. Furthermore, Zn reduced the duration of clinical signs in animals facing respiratory disease and diarrhea. However, consensus is needed about the optimal dose, route, and Zn formulation most appropriate for supporting immunity. In conclusion, while the literature supports that Zn could enhance calf immunity, there is insufficient evidence to adequately determine the extent to which Zn impacts innate immune cell and T-cell functions. Determination of the immune cell functions susceptible to modification by Zn supplementation is an important knowledge gap for enhancing the understanding of Zn and calf immunity.

A cluster-randomized trial of water, sanitation, handwashing and nutritional interventions on stress and epigenetic programming

A regulated stress response is essential for healthy child growth and development trajectories. We conducted a cluster-randomized trial in rural Bangladesh (funded by the Bill & Melinda Gates Foundation, ClinicalTrials.gov NCT01590095) to assess the effects of an integrated nutritional, water, sanitation, and handwashing intervention on child health. We previously reported on the primary outcomes of the trial, linear growth and caregiver-reported diarrhea. Here, we assessed additional prespecified outcomes: physiological stress response, oxidative stress, and DNA methylation (N = 759, ages 1-2 years). Eight neighboring pregnant women were grouped into a study cluster. Eight geographically adjacent clusters were block-randomized into the control or the combined nutrition, water, sanitation, and handwashing (N + WSH) intervention group (receiving nutritional counseling and lipid-based nutrient supplements, chlorinated drinking water, upgraded sanitation, and handwashing with soap). Participants and data collectors were not masked, but analyses were masked. There were 358 children (68 clusters) in the control group and 401 children (63 clusters) in the intervention group. We measured four F2-isoprostanes isomers (iPF(2α)-III; 2,3-dinor-iPF(2α)-III; iPF(2α)-VI; 8,12-iso-iPF(2α)-VI), salivary alpha-amylase and cortisol, and methylation of the glucocorticoid receptor (NR3C1) exon 1F promoter including the NGFI-A binding site. Compared with control, the N + WSH group had lower concentrations of F2-isoprostanes isomers (differences ranging from -0.16 to -0.19 log ng/mg of creatinine, P < 0.01), elevated post-stressor cortisol (0.24 log µg/dl; P < 0.01), higher cortisol residualized gain scores (0.06 µg/dl; P = 0.023), and decreased methylation of the NGFI-A binding site (-0.04; P = 0.037). The N + WSH intervention enhanced adaptive responses of the physiological stress system in early childhood.

Identification of novel F2-isoprostane metabolites by specific UDP-glucuronosyltransferases

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.

Hepatic oxylipin profiles in mouse models of Wilson disease: New insights into early hepatic manifestations

Hepatic inflammation is commonly identified in Wilson disease (WD), a genetic disease of hepatic and brain copper accumulation. Copper accumulation is associated with increased oxidative stress and reactive oxygen species generation which may result in non-enzymatic oxidation of membrane-bound polyunsaturated fatty acids (PUFA). PUFA can be oxidized enzymatically via lipoxygenases (LOX), cyclooxygenases (COX), and cytochrome P450 monooxygenases (CYP). Products of PUFA oxidation are collectively known as oxylipins (OXL) and are bioactive lipids that modulate hepatic inflammation. We examined hepatic OXL profiles at early stages of WD in two mouse models, the toxic milk mouse from The Jackson Laboratory (tx-j) and the Atp7b knockout on a C57Bl/6 background (Atp7b-/-B6). Targeted lipidomic analysis performed by ultra-high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry showed that in both tx-j and Atp7b-/-B6 mice, hepatic OXL profiles were altered with higher thromboxane and prostaglandins levels. The levels of oxidative stress marker, 9-HETE were increased more markedly in tx-j mice. However, both genotypes showed upregulated transcript levels of many genes related to oxidative stress and inflammation. Both genotypes showed higher prostaglandins, thromboxin along with higher PUFA-derived alcohols, diols, and ketones with altered epoxides; the expression of Alox5 was upregulated and many CYP-related genes were dysregulated. Pathway analyses show dysregulation in arachidonic acid and linoleic acid metabolism characterizes mice with WD. Our findings indicate alterations in hepatic PUFA metabolism in early-stage WD and suggest the upregulation of both, non-enzymatic ROS-dependent and enzymatic PUFA oxidation, which could have implications for hepatic manifestations in WD and represent potential targets for future therapies.

Temperature stability of urinary F2-isoprostane and 8-hydroxy-2'-deoxyguanosine

Background

Clinical and epidemiological studies employ long-term temperature storage but the effect of temperature on the stability of oxidative stress (OS) markers is unknown. We investigated the effects of storage at -20 °C and -80 °C over 4-9 months on F2-isoprostanes (F2-IsoP) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in urine of children, a population group among whom the measurement of these markers is still limited.

Methods

Paired spot urine samples from 87 children aged 8.9-16.9 years (52.9% boys) were analyzed. Samples were preserved with 0.005% (w/v) butylated hydroxytoluene, portioned and stored within 2.5 h (median) of collection. Samples were analyzed in duplicate or triplicate using commercial ELISA kits and their correlations were evaluated.

Results

F2-IsoP and 8-OHdG showed high correlations (Spearman rho of 0.90 and 0.97, respectively; P < 0.0001) with storage at -20 °C and -80 °C. There was a strong agreement among categories of values for F2-IsoP (Kappa = 0.76 ± 0.08, agreement = 83.9%, P < 0.0001) and 8-OHdG: (Kappa = 0.83 ± 0.08, agreement = 88.4%, P < 0.0001). The correlation between the temperatures for F2-IsoP concentrations was also high when stored for <4 (0.93), 4 (0.93), and 5 months (0.88), all P < 0.0001. For 8-OHdG, Spearman correlations at <8, 8, and 9 months of storage at -20 °C and -80 °C were 0.95, 0.98, and 0.96 (all P < 0.0001), respectively.

Conclusions

Urine storage with BHT for up to nine months at a temperature of -20 °C to -80 °C yields highly comparable concentrations of F2-IsoP and 8-OHdG.

Association between F2-isoprostanes and self-reported stressors in pregnant americans of African and European ancestry

Background

Poor birth outcomes such as preterm birth/delivery disproportionately affect African Americans compared to White individuals. Reasons for this disparity are likely multifactorial, and include prenatal psychosocial stressors, and attendant increased lipid peroxidation; however, empirical data linking psychosocial stressors during pregnancy to oxidative status are limited.

Methods

We used established scales to measure five psychosocial stressors. Maternal adverse childhood experiences, financial stress, social support, anxiety, and depression were measured among 50 African American and White pregnant women enrolled in the Stress and Health in Pregnancy cohort. Liquid chromatography-tandem mass spectrometry was used to measure biomarkers of oxidative stress (four urinary F2-isoprostane isomers), to estimate oxidative status. Linear regression models were used to evaluate associations between psychosocial stressors, prenatal oxidative status and preterm birth.

Results

After adjusting for maternal obesity, gestational diabetes, and cigarette smoking, African American women with higher oxidative status were more likely to report higher maternal adverse childhood experience scores (β = 0.16, se = 1.07, p-value = 0.024) and depression scores (β = 0.05, se = 0.02, p = 0.014). Higher oxidative status was also associated with lower gestational age at birth (β = -0.13, se = 0.06, p = 0.04) in this population. These associations were not apparent in Whites. However, none of the cross-product terms for race/ethnicity and social stressors reached statistical significance (p > 0.05).

Conclusion

While the small sample size limits inference, our novel data suggest that psychosocial stressors may contribute significantly to oxidative stress during pregnancy, and preterm birth or delivery African Americans. If replicated in larger studies, these findings would support oxidative stress reduction using established dietary or pharmacological approaches present a potential avenue to mitigate adverse effects of psychosocial stressors on birth outcomes.

The Effect of Yucca schidigera Extract on Serum Metabolites of Angus Crossbreed Steers with Metabolomics

This study was conducted to explore the potential effect of Yucca schidigera extract (YSE) on the metabolism of beef cattle. Thirty Angus crossbreed steers were selected, with an initial mean body weight of 506.6 ± 33.3 kg, and assigned to two treatments: a diet with no additives (CON group) and a diet supplemented with 1.75 g/kg of YSE (YSE group) (on a dry matter basis). The experiment lasted for 104 days, with 14 days for adaptation. The results showed that adding YSE could significantly improve the average daily gain (ADG) from 1 to 59 d (15.38%) (p = 0.01) and 1 to 90 d (11.38%) (p < 0.01), as well as dry matter digestibility (DMD) (0.84%) (p < 0.05). The contents of alanine aminotransferase, aspartate aminotransferase, and bilirubin and the total antioxidant capacity were increased and blood urea was reduced in the YSE group, compared to the CON group (p < 0.05). Both the glycerophospholipids and bile acids, including phosphocholine, glycerophosphocholine, PC(15:0/18:2(9Z,12Z)), PE(18:0/20:3(5Z,8Z,11Z)), PE(18:3(6Z,9Z,12Z)/P-18:0), LysoPC(15:0), LysoPC(17:0), LysoPC(18:0), LysoPC(20:5(5Z,8Z,11Z,14Z,17Z)), deoxycholic acid, glycocholic acid, and cholic acid, were upregulated by the addition of YSE. In summary, YSE may improve the ADG by increasing the blood total antioxidant capacity and glycerophospholipid synthesis, maintaining steers under a healthy status that is beneficial for growth. Furthermore, YSE may also increase the expression of bile acid synthesis, thereby promoting DMD, which, in turn, offers more nutrients available for growth.

Oxidative stress mediates associations between preoperative psychosocial phenotype and pain-related outcomes at 6 months following total knee arthroplasty: a longitudinal cohort study

OBJECTIVE

Greater preoperative depression, anxiety, and pain catastrophizing are associated with more severe long-term pain following total knee arthroplasty (TKA). In a secondary analysis of previously reported data, we tested the hypothesis that these associations are mediated by oxidative stress (OS).

DESIGN

A mixed between/within-subjects longitudinal cohort design.

SETTING

A single academic medical center.

SUBJECTS

Osteoarthritis patients (n = 91; 62.6% female) undergoing unilateral TKA.

METHODS

We assessed depression, anxiety, and catastrophizing, as well as markers of central sensitization (widespread pain, temporal summation of pain) preoperatively. Blood samples were then obtained immediately prior to intraoperative tourniquet placement for quantification of in vivo biomarkers of systemic OS, F2-isoprostanes and isofurans. Post-TKA pain intensity (numeric rating scale worst pain [NRS], McGill Pain Questionnaire-2 [MPQ-2]) and function (PROMIS Pain Interference) were assessed at 6 months following TKA.

RESULTS

Greater preoperative depression, catastrophizing, and widespread pain were associated with higher intraoperative combined OS (F2-isoprostanes+isofurans/2), which was in turn associated with higher post-TKA pain intensity and worse function (P < .05). All preoperative phenotype predictors except anxiety were correlated positively with post-TKA pain and/or function (P < .05). Bootstrapped mediation analyses revealed significant (P < .05) indirect (mediated) effects of depression (NRS Worst Pain, MPQ-2, PROMIS Pain Interference), anxiety (MPQ-2, PROMIS Pain Interference), and catastrophizing (PROMIS Pain Interference) on adverse long-term post-TKA outcomes via elevated OS. Central sensitization-related predictors demonstrated only direct effects (P < .05) on post-TKA outcomes that were independent of OS mechanisms.

CONCLUSIONS

Results suggest that the adverse impact of depression, anxiety, and pain catastrophizing on post-TKA pain and functional outcomes are mediated in part by elevated OS.

Selenium deficiency-induced high concentration of reactive oxygen species restricts hypertrophic growth of skeletal muscle in juvenile zebrafish by suppressing TORC1-mediated protein synthesis

Se deficiency causes impaired growth of fish skeletal muscle due to the retarded hypertrophy of muscle fibres. However, the inner mechanisms remain unclear. According to our previous researches, we infer this phenomenon is associated with Se deficiency-induced high concentration of reactive oxygen species (ROS), which could suppress the target of rapamycin complex 1 (TORC1) pathway-mediated protein synthesis by inhibiting protein kinase B (Akt), an upstream protein of TORC1. To test this hypothesis, juvenile zebrafish (45 d post-fertilisation) were fed a basal Se-adequate diet or a basal Se-deficient diet or them supplemented with an antioxidant (DL-α-tocopherol acetate, designed as VE) or a TOR activator (MHY1485) for 30 d. Zebrafish fed Se-deficient diets exhibited a clear Se-deficient status in skeletal muscle, which was not influenced by dietary VE and MHY1485. Se deficiency significantly elevated ROS concentrations, inhibited Akt activity and TORC1 pathway, suppressed protein synthesis in skeletal muscle, and impaired hypertrophy of skeletal muscle fibres. However, these negative effects of Se deficiency were partly (except that on ROS concentration) alleviated by dietary MHY1485 and completely alleviated by dietary VE. These data strongly support our speculation that Se deficiency-induced high concentration of ROS exerts a clear inhibiting effect on TORC1 pathway-mediated protein synthesis by regulating Akt activity, thereby restricting the hypertrophy of skeletal muscle fibres in fish. Our findings provide a mechanistic explanation for Se deficiency-caused retardation of fish skeletal muscle growth, contributing to a better understanding of the nutritional necessity and regulatory mechanisms of Se in fish muscle physiology.

Association between depression and stroke and the role of sociodemographic factors: A study among hypertensive populations

OBJECTIVES

Studies have shown that depression increases the risk of stroke, and that this relationship can be modified by sex. However, few studies have explored this relationship in a hypertensive population, and an examination of sociodemographic factors may be useful in determining whether depression and stroke are related.

MATERIALS AND METHODS

We used data from the National Health and Nutrition Examination Survey conducted between 2005-2018. The relationship between depression and stroke was investigated using a multivariate logistic regression. Effect modification by sex was examined using an interaction analysis model.

RESULTS

Participants with mild or moderate depression had a 53 % (odds ratio, [OR] 1.53; 95 % confidence interval [CI], 1.15-2.04) higher risk of stroke than those without depression, with 1.76 times (95 % CI, 1.14-2.72) greater risk for major depression. Interaction analysis indicated that sex had no effect on this relationship (OR, 1.30; 95 % CI, 0.85-1.47, P=0.430). In comparison with Hispanics, non-Hispanic blacks and others/mixed-race individuals with depression had a greater risk of stroke (OR, 2.26; 95 % CI, 1.5-3.14; OR, 2.67, 95 % CI, 1.29-5.55).

CONCLUSIONS

Our study found that the degree of depression was positively correlated with stroke in a hypertensive population, and that this relationship was not affected by sex.

Primary Processes of Free Radical Formation in Pharmaceutical Formulations of Therapeutic Proteins

Oxidation represents a major pathway for the chemical degradation of pharmaceutical formulations. Few specific details are available on the mechanisms that trigger oxidation reactions in these formulations, specifically with respect to the formation of free radicals. Hence, these mechanisms must be formulated based on information on impurities and stress factors resulting from manufacturing, transportation and storage. In more detail, this article focusses on autoxidation, metal-catalyzed oxidation, photo-degradation and radicals generated from cavitation as a result of mechanical stress. Emphasis is placed on probable rather than theoretically possible pathways.

The Critical Assessment of Oxidative Stress Parameters as Potential Biomarkers of Carbon Monoxide Poisoning

In conventional clinical toxicology practice, the blood level of carboxyhemoglobin is a biomarker of carbon monoxide (CO) poisoning but does not correspond to the complete clinical picture and the severity of the poisoning. Taking into account articles suggesting the relationship between oxidative stress parameters and CO poisoning, it seems reasonable to consider this topic more broadly, including experimental biochemical data (oxidative stress parameters) and patients poisoned with CO. This article aimed to critically assess oxidative-stress-related parameters as potential biomarkers to evaluate the severity of CO poisoning and their possible role in the decision to treat. The critically set parameters were antioxidative, including catalase, 2,2-diphenyl-1-picryl-hydrazyl, glutathione, thiol and carbonyl groups. Our preliminary studies involved patients (n = 82) admitted to the Toxicology Clinical Department of the University Hospital of Jagiellonian University Medical College (Kraków, Poland) during 2015-2020. The poisoning was diagnosed based on medical history, clinical symptoms, and carboxyhemoglobin blood level. Blood samples for carboxyhemoglobin and antioxidative parameters were collected immediately after admission to the emergency department. To evaluate the severity of the poisoning, the Pach scale was applied. The final analysis included a significant decrease in catalase activity and a reduction in glutathione level in all poisoned patients based on the severity of the Pach scale: I°-III° compared to the control group. It follows from the experimental data that the poisoned patients had a significant increase in level due to thiol groups and the 2,2-diphenyl-1-picryl-hydrazyl radical, with no significant differences according to the severity of poisoning. The catalase-to-glutathione and thiol-to-glutathione ratios showed the most important differences between the poisoned patients and the control group, with a significant increase in the poisoned group. The ratios did not differentiate the severity of the poisoning. The carbonyl level was highest in the control group compared to the poisoned group but was not statistically significant. Our critical assessment shows that using oxidative-stress-related parameters to evaluate the severity of CO poisoning, the outcome, and treatment options is challenging.

Urinary oxidative stress biomarkers are associated with preterm birth: an Environmental Influences on Child Health Outcomes program study

BACKGROUND

Preterm birth is the leading cause of infant morbidity and mortality worldwide. Elevated levels of oxidative stress have been associated with an increased risk of delivering before term. However, most studies testing this hypothesis have been conducted in racially and demographically homogenous study populations, which do not reflect the diversity within the United States.

OBJECTIVE

We leveraged 4 cohorts participating in the Environmental Influences on Child Health Outcomes Program to conduct the largest study to date examining biomarkers of oxidative stress and preterm birth (N=1916). Furthermore, we hypothesized that elevated oxidative stress would be associated with higher odds of preterm birth, particularly preterm birth of spontaneous origin.

STUDY DESIGN

This study was a pooled analysis and meta-analysis of 4 birth cohorts spanning multiple geographic regions in the mainland United States and Puerto Rico (208 preterm births and 1708 full-term births). Of note, 8-iso-prostaglandin-F2α, 2,3-dinor-5,6-dihydro-8-iso-prostaglandin-F2α (F2-IsoP-M; the major 8-iso-prostaglandin-F2α metabolite), and prostaglandin-F2α were measured in urine samples obtained during the second and third trimesters of pregnancy. Logistic regression was used to calculate adjusted odds ratios and 95% confidence intervals for the associations between averaged biomarker concentrations for each participant and all preterm births, spontaneous preterm births, nonspontaneous preterm births (births of medically indicated or unknown origin), and categories of preterm birth (early, moderate, and late). Individual oxidative stress biomarkers were examined in separate models.

RESULTS

Approximately 11% of our analytical sample was born before term. Relative to full-term births, an interquartile range increase in averaged concentrations of F2-IsoP-M was associated with higher odds of all preterm births (odds ratio, 1.29; 95% confidence interval, 1.11-1.51), with a stronger association observed for spontaneous preterm birth (odds ratio, 1.47; 95% confidence interval, 1.16-1.90). An interquartile range increase in averaged concentrations of 8-iso-prostaglandin-F2α was similarly associated with higher odds of all preterm births (odds ratio, 1.19; 95% confidence interval, 0.94-1.50). The results from our meta-analysis were similar to those from the pooled combined cohort analysis.

CONCLUSION

Here, oxidative stress, as measured by 8-iso-prostaglandin-F2α, F2-IsoP-M, and prostaglandin-F2α in urine, was associated with increased odds of preterm birth, particularly preterm birth of spontaneous origin and delivery before 34 completed weeks of gestation.

Lipid peroxidation mediates the association between iron overload and liver injury: cross-sectional and longitudinal analyses in general Chinese urban adults

Iron overload has been associated with acute/chronic organ failure, but whether iron overload induces liver injury remains unclear. The objectives of this study were to assess the relationship between urinary iron and serum alanine aminotransferase (ALT, a biomarker for liver injury), and investigate the potential mediating roles of lipid peroxidation and oxidative DNA damage in such association. Levels of urinary iron, serum ALT, and urinary biomarkers of lipid peroxidation (8-iso-prostaglandin-F_2α [8-iso-PGF_2α]) and oxidative DNA damage (8-hydroxy-deoxyguano-sine [8-OHdG]) were measured among 5386 observations of 4220 participants from the Wuhan-Zhuhai cohort. The relationships of urinary iron with serum ALT and risk of hyperALT were evaluated by linear mixed model and logistic regression model, respectively. The mediating roles of 8-iso-PGF_2α and 8-OHdG were assessed by mediation analyses. This cross-sectional analysis found that urinary iron was positively associated with ALT (β = 0.032; 95% CI: 0.020, 0.044) and hyperALT prevalence (OR = 1.127; 95% CI: 1.065, 1.192). After 3 years of follow-up, participants with persistent high iron levels had increased risk of developing hyperALT (RR = 3.800; 95% CI: 1.464, 9.972) when compared with those with persistent low iron levels. In addition, each 1% increase in urinary iron was associated with a 0.146% (95% CI: 0.128%, 0.164%) increase and a 0.192% (95% CI: 0.154%, 0.229%) increase in 8-iso-PGF_2α and 8-OHdG, respectively. Urinary 8-iso-PGF_2α (β = 0.056; 95% CI: 0.039, 0.074) was positively associated with ALT, while the association between 8-OHdG and ALT was insignificant. Furthermore, increased 8-iso-PGF_2α significantly mediated 22.48% of the urinary iron-associated ALT increment. Our study demonstrated that iron overload was significantly associated with liver injury, which was partly mediated by lipid peroxidation. Controlling iron intake and regulating lipid peroxidation may help in preventing liver injury.

Comparison of the Effects of Yucca saponin, Yucca schidigera, and Quillaja saponaria on Growth Performance, Immunity, Antioxidant Capability, and Intestinal Flora in Broilers

The purpose of this study is to investigate the effects of Yucca saponin (YSa), Yucca schidigera (YS), and Quillaja Saponaria (QS) on growth performance, nitrogen metabolism, immune ability, antioxidant capability, and intestinal flora of yellow-feather broilers. This study randomly divided a total of 480 1-day yellow-feather broilers into 4 treatment groups. Factors in the 4 groups included CON group (basic diet), YSa group (basic diet mixed with 500 mg/kg YSa), YS group (basic diet mixed with 500 mg/kg YS), and QS group (basic diet mixed with 500 mg/kg QS). Throughout the 56-day study period, YSa, YS, and QS groups had higher average daily gain in broilers than the CON group (p < 0.01). The YS group had a lower feed gain ratio (F: G) in broilers than the CON group (p < 0.05). YSa, YS, and QS showed increased serum immunoglobin A (IgA), immunoglobin Y (IgY), immunoglobin M (IgM), and total antioxidant capacity (T-AOC) levels; enhanced acetic acid, butyric acid, and valeric acid levels of cecal content; and reduced contents of ammonia nitrogen, urea nitrogen, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and malondialdehyde (MDA) in serum in broilers (p < 0.05). The relative abundance of Lachnoclostridium in the QS group was decreased compared with that in the CON group (p < 0.05). Higher IgA and IgY sera contents were observed in the YS group compared to the YSa and QS groups (p < 0.05). In contrast with the QS group, the serum IL-6 concentration of the YS group was reduced (p < 0.05). In conclusion, YSa, YS, and QS promoted growth performance, nitrogen metabolism, immunity, antioxidant capability, and intestinal flora in broilers. Through the comparison of YSa, YS, and QS, it was found that YS is more suitable as a feed additive to ameliorate the healthy growth of broilers.

The Contribution of the Nrf2/ARE System to Mechanotransduction in Musculoskeletal and Periodontal Tissues

Mechanosensing plays an essential role in maintaining tissue functions. Across the human body, several tissues (i.e., striated muscles, bones, tendons, ligaments, as well as cartilage) require mechanical loading to exert their physiological functions. Contrary, mechanical unloading triggers pathological remodeling of these tissues and, consequently, human body dysfunctions. At the cellular level, both mechanical loading and unloading regulate a wide spectrum of cellular pathways. Among those, pathways regulated by oxidants such as reactive oxygen species (ROS) represent an essential node critically controlling tissue organization and function. Hence, a sensitive balance between the generation and elimination of oxidants keeps them within a physiological range. Here, the Nuclear Factor-E2-related factor 2/Antioxidant response element (Nrf2/ARE) system plays an essential role as it constitutes the major cellular regulation against exogenous and endogenous oxidative stresses. Dysregulations of this system advance, i.a., liver, neurodegenerative, and cancer diseases. Herein, we extend our comprehension of the Nrf2 system to the aforementioned mechanically sensitive tissues to explore its role in their physiology and pathology. We demonstrate the relevance of it for the tissues' functionality and highlight the imperative to further explore the Nrf2 system to understand the physiology and pathology of mechanically sensitive tissues in the context of redox biology.

Therapeutic impact of purified Trichoderma viride L-asparaginase in murine model of liver cancer and in vitro Hep-G2 cell line

BACKGROUND

Hepatocellular carcinoma (HCC) is among the common cancers, but difficult to diagnose and treat. L-asparaginase has been introduced in the treatment protocol of pediatric acute lymphoblastic leukemia (ALL) since the 1960s with a good outcome and increased survival rates to nearly 90%. Moreover, it has been found to have therapeutic potential in solid tumors. Production of glutaminase-free-L-asparaginase is of interest to avoid glutaminase-related toxicity and hypersensitivity. In the current study, an extracellular L-asparaginase that is free of L-glutaminase was purified from the culture filtrate of an endophytic fungus Trichoderma viride. The cytotoxic effect of the purified enzyme was evaluated in vitro against a panel of human tumor cell lines and in vivo against male Wister albino mice intraperitoneally injected with diethyl nitrosamine (200 mg/kg bw), followed by (after 2 weeks) oral administration of carbon tetrachloride (2 mL/kg bw). This dose was repeated for 2 months, and after that, the blood samples were collected to estimate hepatic and renal injury markers, lipid profiles, and oxidative stress parameters.

RESULTS

L-asparaginase was purified from T. viride culture filtrate with 36 purification folds, 688.1 U/mg specific activity, and 38.9% yield. The highest antiproliferative activity of the purified enzyme was observed against the hepatocellular carcinoma (Hep-G2) cell line, with an IC50 of 21.2 g/mL, which was higher than that observed for MCF-7 (IC50 34.2 g/mL). Comparing the DENA-intoxicated group to the negative control group, it can be demonstrated that L-asparaginase adjusted the levels of the liver function enzymes and the hepatic injury markers that had previously changed with DENA intoxication. DENA causes kidney dysfunction and altered serum albumin and creatinine levels as well. Administration of L-asparaginase was found to improve the levels of the tested biomarkers including kidney and liver function tests. L-asparaginase treatment of the DENA-intoxicated group resulted in a significant improvement in the liver and kidney tissues to near normal similar to the healthy control group.

CONCLUSION

The results suggest that this purified T. viride L-asparaginase may be able to delay the development of liver cancer and may be used as a potential candidate for future application in medicine as an anticancer medication.

Ability of a Polyphenol-Rich Nutraceutical to Reduce Central Nervous System Lipid Peroxidation by Analysis of Oxylipins in Urine: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Isoprostanes (IsoPs) are lipid peroxidation biomarkers that reveal the oxidative status of the organism without specifying which organs or tissues it occurs in. Similar compounds have recently been identified that can assess central nervous system (CNS) lipid peroxidation status, usually oxidated by reactive oxygen species. These compounds are the neuroprostanes (NeuroPs) derived from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and the F2t-dihomo-isoprotanes derived from adrenic acid (AdA). The aim of the present investigation was to evaluate whether the long-term nutraceutical consumption of high polyphenolic contents (600 mg) from fruits (such as berries) and vegetables shows efficacy against CNS lipid peroxidation in urine biomarkers. A total of 92 subjects (47 females, 45 males, age 34 ± 11 years old, weight 73.10 ± 14.29 kg, height 1.72 ± 9 cm, body mass index (BMI) 24.40 ± 3.43 kg/m2) completed a randomized, cross-over, double-blind study after an intervention of two periods of 16 weeks consuming either extract (EXT) or placebo (PLA) separated by a 4-week washout period. The results showed significant reductions in three AdA-derived metabolites, namely, 17-epi-17-F2t-dihomo-IsoPs (Δ −1.65 ng/mL; p < 0.001), 17-F2t-dihomo-IsoPs (Δ −0.17 ng/mL; p < 0.015), and ent-7(RS)-7-F2t-dihomo-IsoPs (Δ −1.97 ng/mL; p < 0.001), and one DHA-derived metabolite, namely, 4-F4t-NeuroP (Δ −7.94 ng/mL; p < 0.001), after EXT consumption, which was not observed after PLA consumption. These data seem to show the effectiveness of the extract for preventing CNS lipid peroxidation, as determined by measurements of oxylipins in urine through Ultra-High-Performance Liquid Chromatography triple quadrupole tandem mass spectrometry (UHPLC-QqQ-ESI-MS/MS).

Oxidative Stress and Cardiovascular Risk Factors: The Coronary Artery Risk Development in Young Adults (CARDIA) Study

Introduction—Oxidative stress is linked to cardiovascular diseases (CVD) and is suggested to vary by sex. However, few population-level studies have explored these associations and the majority comprise populations with advanced CVD. We assessed urinary isoprostane concentrations, a standard measure of oxidative stress, in a relatively young and healthy cohort, hypothesizing that higher oxidative stress is associated with an adverse cardiometabolic profile and female sex. Methods—Oxidative stress was measured in 475 women and 266 men, aged 48–55 years, from the Coronary Artery Risk Development in Young Adults (CARDIA) study using urinary 8-isoprostane (IsoP) and 2,3-dinor-8-isoprostane (IsoP-M). Multivariable-adjusted regression was used to evaluate cross-sectional associations. As secondary analysis, previously measured plasma F2-isoprostanes (plasma IsoP) from another CARDIA subset was similarly analyzed. Results—Mean (SD) ages for men and women were 52.1(2.3) and 52.2(2.2) years, respectively (p = 0.46), and 39% of the participants self-identified as Black (vs. White). Before adjustments, female sex was associated with higher median urinary IsoP (880 vs. 704 ng/g creatinine in men; p < 0.01) and IsoP m (1675 vs. 1284 ng/g creatinine in men; p < 0.01). Higher body mass index (BMI), high-density cholesterol (HDL-C), and triglycerides, current smoking, and less physical activity were associated with higher oxidative stress. Diabetes was not associated with urinary IsoP but was associated with lower IsoP m and plasma IsoP. Higher serum creatinine showed diverging associations with higher plasma and lower urinary isoprostane concentrations. Conclusions—Different isoprostane entities exhibit varying association patterns with CVD risk factors, and therefore are complementary, rather than interchangeable, in assessment of oxidative stress. Still, consistently higher isoprostanes among women, smokers, less active persons, and those with higher BMI and plasma triglycerides could reflect higher oxidative stress among these groups. While urinary isoprostanes are indexed to urinary creatinine due to variations in concentration, caution should be exercised when comparing groups with differing serum creatinine.

Effects of a Saccharomyces cerevisiae fermentation product-supplemented diet on fecal characteristics, oxidative stress, and blood gene expression of adult dogs undergoing transport stress

Previously, a Saccharomyces cerevisiae fermentation product (SCFP) was shown to positively alter fecal microbiota, fecal metabolites, oxidative stress, and circulating immune cell function of adult dogs. The objective of this study was to measure the effects of SCFP on fecal characteristics, serum oxidative stress biomarkers, and whole blood gene expression of dogs undergoing transport stress. Sixteen adult pointer dogs [8M, 8F; mean age = 6.7 ± 2.1 yr; mean body weight (BW) = 25.5 ± 3.9 kg] were used in a randomized crossover design study. All dogs were fed a control diet for 4 wk, then randomly assigned to a control or SCFP-supplemented diet (formulated to include approximately 0.13% of the active SCFP ingredient) and fed to maintain BW for 11 wk. A 6-wk washout preceded the second 11-wk experimental period with dogs receiving opposite treatments. After 11 wk, fresh fecal and blood samples were collected before and after transport in a van for 45 min. Change from baseline data (i.e., before and after transport) were analyzed using the Mixed Models procedure of SAS 9.4, with P < 0.05 being significant and P < 0.10 being trends. Change in serum malondialdehyde concentrations increased (P < 0.05) and serum 8-isoprostane concentrations tended to increase (P < 0.10) in dogs fed SCFP, but decreased (P < 0.05) in control dogs after transport. Other serum markers were unaffected by diet during transport stress. Fecal dry matter percentage tended to be affected (P < 0.10) by diet during transport stress, being reduced in control dogs, but stable in dogs fed SCFP. Other fecal characteristics were unaffected by diet during transport stress. Genes associated with activation of innate immunity were impacted by diet in response to transport stress, with blood cyclooxygenase-2 and malondialdehyde mRNA expression being increased (P < 0.05) in control dogs, but stable or decreased in dogs fed SCFP. Expression of other genes was unaffected by diet during transport stress. These data suggest that the benefits of feeding a SCFP during transport stress may be mediated through suppression of innate immune cell activation.

Perioperative oxidative stress predicts subsequent pain-related outcomes in the 6 months after total knee arthroplasty

ABSTRACT

Total knee arthroplasty (TKA) is effective for pain reduction in most patients, but 15% or more report unsatisfactory long-term pain outcomes. We tested whether oxidative stress (OS) related to extended tourniquet application during TKA and subsequent ischemic reperfusion (IR) contributed to adverse post-TKA pain outcomes. Blood samples were obtained in 91 patients with osteoarthritis (63% female) undergoing TKA before tourniquet placement (T1), 45 minutes after tourniquet inflation (T2), and 15 minutes after tourniquet removal (T3). Plasma levels of F 2 -isoprostanes and isofurans, the most specific measures of in vivo OS, were quantified. Pain intensity and function were assessed at baseline and again at 6 weeks and 6 months after TKA. Results indicated that higher Combined OS (F 2 -isoprostanes + isofurans/2) at T1 baseline and larger increases in Combined OS from T1 to T2 were associated with higher baseline-corrected past 24-hour worst and average pain intensity (numeric rating scale) and higher past week McGill Pain Questionnaire-2 total scores at 6-month follow-up ( P 's < 0.05). Increases in Combined OS from T1 to T3, which should most directly capture OS and IR injury related to tourniquet use, were not associated with short-term or long-term post-TKA pain outcomes. Longer ischemia duration was unexpectedly associated with lower baseline-corrected pain intensity at 6-month follow-up. Combined OS was not linked to functional outcomes at either follow-up. Elevated perioperative OS seems to exert small but significant adverse effects on long-term post-TKA pain outcomes, although this OS seems unrelated to IR injury associated with extended tourniquet use.

Oxidative stress coping capacity (OSC) value: Development and validation of an in vitro measurement method for blood plasma using electron paramagnetic resonance spectroscopy (EPR) and vitamin C

Oxidative stress as a driver of disease is reinforcing the trend towards supplementation with antioxidants. While antioxidants positively influence the redox status when applied at physiological doses, higher concentrations may have pro-oxidative effects. Precise assessment methods for testing the supply of antioxidants are lacking. Using in-situ-irradiation as stressor and electron paramagnetic resonance (EPR) spectroscopy as readout system for formed radicals, a stress response assessment method was developed, using protein solutions and plasma samples from transfusion medicine. The method was validated in a double-blind placebo-controlled in vivo cross-over pilot study in blood plasma samples of individuals before and after vitamin C supplementation. Reference measurements were performed for the exogenous antioxidants β-carotene and vitamin C, and glutathione as an endogenous representative. Malondialdehyde was studied for oxidative stress indication. Protein solutions without antioxidants showed a linear increase in radical concentration during irradiation. The in-vitro-addition of vitamin C or plasma samples from subjects displayed two slopes (m₁, m₂) for radical production, whereby m₁ represented the amount of antioxidants and proteins, m₂ only the protein content. These two slopes in combination with the intervening transition area (T) were used to calculate the oxidative stress coping capacity (OSC), which correlated positively with vitamin C concentration in blood plasma, while oxidative stress biomarkers showed only fluctuations within their reference ranges. Furthermore, a selective radical quenching mechanism for vitamin C was observed: the proportion of reactive oxygen species (ROS) in the plasma samples was degraded in dependence to the vitamin C concentration ingested. The proportion of lipid oxygen species (LOS) remained stable while the ascorbyl radical increased with higher vitamin C intake. OSC may represent a sensitive method to detect treatment effects on the redox status in vivo in future validation and treatment studies, and potentially in clinical routine.

Protective effects of liposomes encapsulating ferulic acid against CCl4-induced oxidative liver damage in vivo rat model

Antioxidants are useful for the treatment of oxidative stress mediated liver damage. A naturally occurring antioxidant γ-oryzanol is rapidly hydrolyzed to its active hydrophobic metabolite, ferulic acid, inside the body. Limitations associated with the hydrophobicity of ferulic acid can be overcome by encapsulating in a liposomal formulation. As intravenously administered nanoparticles (including liposomes) can effectively reach the liver, such systems may be suitable drug delivery carriers to treat liver injury. In this study, we prepared a liposomal formulation of ferulic acid (ferulic-lipo) and examined its effects on liver damage induced by CCl₄. Ferulic-lipo were ~100 nm in size and drug encapsulation efficiency was about 92%. Ferulic-lipo showed potent scavenging efficacy against hydroxyl radical compared to α-tocopherol liposomes. Ferulic-lipo significantly prevented CCl₄-mediated cytotoxicity in human hepatocarcinoma cells. Furthermore, intravenous administration of ferulic-lipo significantly reduced alanine aminotransferase and aspartate amino transferase levels in a rat model of liver injury. CCl₄-mediated reactive oxygen species generation in liver was also reduced by intravenous administration of ferulic-lipo. Hepatoprotective effects of ferulic-lipo were demonstrated by histological observation of CCl₄-induced liver tissue damage. Therefore, ferulic-lipo exhibit potent antioxidative capacity and were suggested to be an effective formulation for prevention of oxidative damage of liver tissue.

Association between lipid peroxidation biomarkers and microRNA expression profiles

BACKGROUND

In-vitro and animal studies demonstrate that epigenetic regulation may play an important role in lipid peroxidation. No human study to date has directly evaluated microRNAs (miRNAs), as epigenetic modulators, in relation to systemic levels of lipid peroxidation.

OBJECTIVES

To evaluate associations between systemic levels of lipid peroxidation and miRNA expression profiles in women.

METHODS

Included in the analysis were 92 women aged 40-70 years, a subset of the Shanghai Women's Health Study (SWHS). Lipid peroxidation was assessed by urinary markers F₂-isoprostanes (F₂-IsoPs), the products of free radical-catalyzed peroxidation of arachidonic acid, and its major metabolite after β-oxidation, 2,3-dinor-5,6-dihydro-15-F_2t-IsoP (F₂-IsoP-M), with GC/NICI-MS assays. Expression levels of 798 miRNAs were quantified in peripheral plasma with NanoString nCounter assays. A multivariable linear regression model was used to examine the association between lipid peroxidation and miRNA expression.

RESULTS

After adjusting for potential confounders, 29 miRNAs and 213 miRNAs were associated with F₂-IsoPs and F₂-IsoP-M, respectively. When further controlling for multiple comparisons, none of these nominally significant associations with F₂-IsoPs was retained, whereas 71 of 213 miRNAs associated with F₂-IsoP-M remained. The predicted targets of the F₂-IsoP-M associated miRNAs were enriched for several lipid peroxidation-related processes such as PI3K/AKT, MAPK, FOXO and HIF-1 signaling pathways. Moreover, 10 miRNAs (miR-93-5p, miR-761, miR-301b-3p, miR-497-5p, miR-141-3p, miR-186-5p, miR-126-3p, miR-200b-3p, miR-520d-3p, and miR-363-3p) exhibited functional interactions with 50 unique mRNAs targets involved in the regulation of β-oxidation.

CONCLUSIONS

To our knowledge, this study, for the first time, provides human data suggesting that miRNA expression may be linked to lipid peroxidation products and their metabolism.

Dietary Supplementation with Epicatechin Improves Intestinal Barrier Integrity in Mice

Epicatechin (EPI) is a dietary flavonoid that is present in many foods and possesses various bioactivities. We assessed the effects of EPI supplementation on intestinal barrier integrity in mice. Thirty-six mice were assigned to three groups and fed a standard diet or a standard diet supplemented with 50 or 100 mg EPI/kg (n = 12 per group). After 21 days of rearing, blood and intestinal samples were collected from eight randomly selected mice. Supplementation with 50 and 100 mg/kg EPI decreased (p < 0.05) the serum diamine oxidase activity and _D-lactic acid concentration and increased (p < 0.05) the duodenal, jejunal, and ileal abundance of tight junction proteins, such as occludin. Moreover, it lowered (p < 0.05) the duodenal, jejunal, and ileal tumor necrosis factor-α contents and enhanced (p < 0.05) the duodenal and jejunal catalase activities and ileal superoxide dismutase activity. Supplementation with a lower dose (50 mg/kg) decreased (p < 0.05) the ileal interleukin-1β content, whereas supplementation with a higher dose (100 mg/kg) increased (p < 0.05) the duodenal and jejunal glutathione peroxidase activities. Furthermore, supplementation with 50 and 100 mg/kg EPI decreased (p < 0.05) cell apoptosis, cleaved cysteinyl aspartate-specific proteinase-3 (caspase-3), and cleaved caspase-9 contents in the duodenum, jejunum, and ileum. In conclusion, EPI could improve intestinal barrier integrity in mice, thereby suppressing intestinal inflammation and oxidative stress and reducing cell apoptosis.

Oxidative Stress and DNA Damage Markers in Colorectal Cancer

Oxidative stress (OS) and inflammation are known to play an important role in chronic diseases, including cancer, and specifically colorectal cancer (CRC). The main objective of this study was to explore the diagnostic potential of OS markers in patients with CRC, which may translate into an early diagnosis of the disease. To do this, we compared results with those in a group of healthy controls and assessed whether there were significant differences. In addition, we explored possible correlations with the presence of tumors and tumor stage, with anemia and with inflammatory markers used in clinical practice. The study included 80 patients with CRC and 60 healthy controls. The following OS markers were analyzed: catalase (CAT), reduced glutathione (GSH) and oxidized glutathione (GSSG) in serum; and 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) and F2-isoprotanes in urine (F2-IsoPs). Tumor markers (CEA and CA 19.9), anemia markers (hemoglobin, hematocrit and medium corpuscular volume) and inflammatory markers (leukocytes, neutrophils, N/L index, platelets, fibrinogen, C-reactive protein, CRP and IL-6) were also determined. Comparison of means between patients and controls revealed highly significant differences for all OS markers, with an increase in the prooxidant markers GSSG, GSSG/GSH ratio, 8-oxodG and F2-IsoPs, and a decrease in the antioxidant markers CAT and GSH. Tumor and inflammatory markers (except CRP) correlated positively with GSSG, GSSG/GSH ratio, 8-oxodG and F2-IsoPs, and negatively with CAT and GSH. In view of the results obtained, OS markers may constitute a useful tool for the early diagnosis of CRC patients.

Associations between mixtures of urinary phthalate metabolite concentrations and oxidative stress biomarkers among couples undergoing fertility treatment

Phthalate exposure has been associated with adverse reproductive outcomes and oxidative stress is a potential mechanism by which they act. However, few human studies have explored co-exposure confounding or joint effects. Furthermore, most studies examine associations between biomarkers of exposure and oxidative stress from the same urine sample. We investigated single-exposure, co-exposure-adjusted, and joint associations between phthalate metabolites and oxidative stress in the Environment and Reproductive Health (EARTH) study among couples undergoing fertility treatment. We examined cross-sectional associations in both women and men, and longitudinal associations in women. Urine was collected in the follicular phase (women only) and at the time of fertility procedure (women and men), and analyzed for 11 phthalate metabolites. Urine from the time of fertility procedure was analyzed for oxidative stress biomarkers, including free 8-iso-prostaglandin F2α (8-iso-PGF2α), its primary metabolite (2,3-dinor-5,6-dihydro-15-F2t-isoprostane [F2-IsoP-M]), and prostaglandin F2α (PGF2α). Linear mixed effects models were used to estimate single-exposure associations. Bayesian Kernel Machine Regression (BKMR) was used to adjust for co-exposures and to estimate joint effects. Among women, we observed positive associations between all phthalate metabolites and oxidative stress biomarkers in single-exposure models, but there was clear co-exposure confounding. For instance, in a single-exposure model, we estimated a 63% (95% confidence interval: 51, 77) increase in the 8-iso-PGF2α metabolite per interquartile range (IQR) difference in mono-n-butyl phthalate (MBP) versus a 34% (95% credible interval: 12, 60) increase in co-adjusted models. However, several phthalate metabolites remained associated with oxidative stress in co-exposure models, and the joint effects of all exposures were high (e.g., an 114% increase in the 8-iso-PGF2α metabolite per IQR difference in all exposures). Longitudinal results were also attenuated compared to cross-sectional results in women; however, the joint effect of all exposures and the 8-iso-PGF2α metabolite remained positive and statistically significant (11% increase per IQR difference in all exposures, 95% credible interval: 0.2, 23). In men, associations were generally less pronounced, although the joint effect of the mixture on 8-iso-PGF2α was above the null. Because oxidative stress is related to reproductive success among couples seeking fertility treatment, mitigating phthalate exposure should be considered as a potentially beneficial measure.

Oxidative Stress Biomarkers in the Diagnosis and Prognosis

Oxidative stress describes the state of a cell where there is an imbalance between free radical formation and antioxidants due to either excess formation of reactive oxygen species (ROS) or inadequate antioxidant defence. It is very well known that oxidative stress plays an important role in the pathophysiology of various diseases through impaired intracellular redox homeostasis. To evaluate and imply the excess production of ROS, various biomarkers are used and suggested, yet it is also known that there is a lack of standardization and validation for these methods. It is almost very difficult to measure ROS directly because of their short half-life, yet it is still possible with a suitable technique. The most frequently used biomarkers are represented by oxidized macromolecules such as lipids, proteins, and nucleic acids, which are modified via ROS, and also the amounts or activities of antioxidant molecules and enzymes, respectively. There are also various genetic biomarkers measuring the susceptibility of modification due to oxidative stress. However, the preferred biomarker would be dependent on the aim of the study and the clinical relevance.

The association between prenatal F2-isoprostanes and child wheeze/asthma and modification by maternal race

BACKGROUND

Childhood wheeze, asthma, and allergic rhinitis are common and likely have prenatal origins. Oxidative stress is associated with respiratory disease, but the association of oxidative stress during the prenatal period with development of respiratory and atopic disease in childhood, particularly beyond the infancy period, is unknown. This study aims to investigate associations between prenatal oxidative stress, measured by maternal urinary F2-isoprostanes, and child respiratory outcomes, including effect modification by maternal race.

METHODS

We prospectively studied Black (n = 717) and White (n = 363) mother-child dyads. We measured F2-isoprostanes in 2nd-trimester urine (ng/mg-creatinine). At approximately age 4, we obtained parent report of provider-diagnosed asthma (ever), current wheeze, current asthma (diagnosis, symptoms and/or medication), and current allergic rhinitis (current defined as previous 12 months). We used multivariable logistic regression to estimate adjusted odds ratios (aOR) and 95% confidence intervals (95%CI) per interquartile range (IQR) increase in F2-isoprostane concentration, controlling for confounders. We examined modification by maternal race using interaction terms.

RESULTS

The prevalence of provider-diagnosed asthma and current wheeze, asthma and allergic rhinitis was 14%, 19%, 15%, and 24%, respectively. Median (IQR) F2-isoprostane levels were 2.1 (1.6, 2.9) ng/mg-creatinine. Associations between prenatal F2-isoprostanes and provider-diagnosed asthma, current wheeze, and current asthma were modified by maternal race. Results were strongest for current wheeze (aOR [95%CI]: 1.55 [1.16, 2.06] for White; 0.98 [0.78, 1.22] for Black; p-interaction = 0.01). We observed no association between F2-isoprostanes and allergic rhinitis.

CONCLUSION

Prenatal urinary F2-isoprostanes may be a marker associated with childhood wheeze/asthma in certain populations. Research is needed to understand underlying mechanisms and racial differences.

Versatile Enzymology and Heterogeneous Phenotypes in Cobalamin Complementation Type C Disease

Nutritional deficiency and genetic errors that impair the transport, absorption, and utilization of vitamin B₁₂ (B₁₂) lead to hematological and neurological manifestations. The cblC disease (cobalamin complementation type C) is an autosomal recessive disorder caused by mutations and epi-mutations in the MMACHC gene and the most common inborn error of B₁₂ metabolism. Pathogenic mutations in MMACHC disrupt enzymatic processing of B₁₂, an indispensable step before micronutrient utilization by the two B₁₂-dependent enzymes methionine synthase (MS) and methylmalonyl-CoA mutase (MUT). As a result, patients with cblC disease exhibit plasma elevation of homocysteine (Hcy, substrate of MS) and methylmalonic acid (MMA, degradation product of methylmalonyl-CoA, substrate of MUT). The cblC disorder manifests early in childhood or in late adulthood with heterogeneous multi-organ involvement. This review covers current knowledge on the cblC disease, structure–function relationships of the MMACHC protein, the genotypic and phenotypic spectra in humans, experimental disease models, and promising therapies.

Packed-Fiber Solid Phase-Extraction Coupled with HPLC-MS/MS for Rapid Determination of Lipid Oxidative Damage Biomarker 8-Iso-Prostaglandin F2α in Urine

The 8-iso-prostaglandin F2α (8-iso-PGF2α) biomarker is used as the gold standard for tracing lipid oxidative stress in vivo. The analysis of urinary 8-iso-PGF2α is challenging when dealing with trace amounts of 8-iso-PGF2α and the complexity of urine matrixes. A packed-fiber solid-phase extraction (PFSPE)−coupled with HPLC-MS/MS−method, based on polystyrene (PS)-electrospun nanofibers, was developed for the specific determination of 8-iso-PGF2α in urine and compared with other newly developed LC-MS/MS methods. The method, which simultaneously processed 12 samples within 5 min on a self-made semi-automatic array solid-phase extraction processor, was the first to introduce PS-electrospun nanofibers as an adsorbent for the extraction of 8-iso-PGF2α and was successfully applied to real urine samples. After optimizing the PFSPE conditions, good linearity in the range of 0.05−5 ng/mL with R2 > 0.9996 and a satisfactory limit of detection of 0.015 ng/mL were obtained, with good intraday and interday precision (RSD < 10%) and recoveries of 95.3−103.8%. This feasible method is expected to be used for the batch quantitative analysis of urinary 8-iso-PGF2α.

Anti-Inflammatory and Antioxidant Capacity of a Fruit and Vegetable-Based Nutraceutical Measured by Urinary Oxylipin Concentration in a Healthy Population: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Oxylipins, lipid biomarkers of inflammation are considered the gold standard method to evaluate the inflammatory and antioxidant status. The aim of the present study was to investigate whether the administration of a polyphenolic extract shot in the form of a nutraceutical was able to reduce inflammation, measured in urine markers. Ninety-two participants (45 males, 47 females, age 34 ± 11 years, weight 73.10 ± 14.29 kg, height 1.72 ± 9 cm, BMI 24.40 ± 3.43 kg/m2) completed the study after an intervention of two 16-week periods consuming extract or placebo separated by a 4-week washout period. The results showed significant differences in terms of reduction of different pro-inflammatory oxylipins (15-keto-PGF2α (from 0.90 ± 0.25 ng/mL to 0.74 ± 0.19 ng/mL p < 0.05), ent-PGF2α (from 1.59 ± 0.37 ng/mL to 1.44 ± 0.32 ng/mL p < 0.05), 2,3-dinor-15-F2t-Isop) (from 1.17 ± 0.35 ng/mL to 1.02 ± 0.27 ng/mL p < 0.05), in total oxylipins count (from 8.03 ± 1.86 ng/mL to 7.25 ± 1.23 ng/mL p < 0.05), and increase in PGE2 (from 1.02 ± 0.38 ng/mL to 1.26 ± 0.38 ng/mL p < 0.05) which has an anti-inflammatory character, after extract consumption compared to placebo. The available data seem to indicate that long-term consumption of a nutraceutical with high polyphenol content improves inflammation and oxidation parameters measured in urine, through UHPLC-QqQ-ESI-MS/MS.

Oxidative Stress and Menopausal Status: The Coronary Artery Risk Development in Young Adults Cohort Study

Background: Low endogenous estrogen concentrations after menopause may contribute to higher oxidative stress and greater cardiovascular disease (CVD) risk. However, differences in oxidative stress between similarly aged premenopausal and postmenopausal women are not well-characterized on a population level. We hypothesized that urinary isoprostane concentrations, a standard measure of systemic oxidative stress, are higher in women who have undergone menopause compared to premenopausal women. Methods and Results: We examined differences in urinary 8-isoprostane (iPF_2α-III) and 2,3-dinor-8-isoprostane (iPF_2α-III-M) indexed to urinary creatinine between 279 postmenopausal and 196 premenopausal women in the Coronary Artery Risk Development in Young Adults (CARDIA) study, using linear regression with progressive adjustment for sociodemographic factors and traditional CVD risk factors. Unadjusted iPF_2α-III-M concentrations were higher among postmenopausal compared to premenopausal women (Median [25th, 75th percentile]: 1762 [1178, 2974] vs. 1535 [1067, 2462] ng/g creatinine; p = 0.01). Menopause was associated with 25.5% higher iPF_2α-III-M (95% confidence interval [6.5-47.9]) adjusted for age, race, college education, and field center. Further adjustments for tobacco use (21.2% [2.9-42.6]) and then CVD risk factors (18.8% [0.1-39.6]) led to additional partial attenuation. Menopause was associated with higher iPF_2α-III in Black but not White women. Conclusions: We conclude that postmenopausal women had higher oxidative stress, which may contribute to greater CVD risk. ClinicalTrials.gov Identifier: NCT00005130.

Association between lipid peroxidation and risk of type 2 diabetes in women

In-vitro and animal studies demonstrate that lipid peroxidation plays an important role in the pathogenesis of type 2 diabetes (T2D). However, human data from prospective studies are limited and contradictory. We used data originally collected in two nested case-control studies of cancer to prospectively evaluate whether systemic levels of lipid peroxidation were associated with incidence of T2D in 1917 women who were 40-70 years old and diabetes-free at baseline. Lipid peroxidation was measured by urinary F₂-isoprostanes (F₂-IsoPs) and its major metabolite 2,3-dinor-5,6-dihydro-15-F_2t-IsoP (F₂-IsoP-M) with GC/NICI-MS assays. The Cox regression model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident T2D. After a median follow-up of 10.1 years, 187 women were diagnosed with T2D. Urinary concentrations of both F₂-IsoPs and F₂-IsoP-M were significantly higher in T2D cases than in non-cases. Both biomarkers were positively associated with subsequent risk of T2D in multivariable-adjusted Cox models. When further adjusted for body mass index (BMI), the positive association with F₂-IsoP-M was attenuated and no longer statistically significant, whereas the association with F₂-IsoPs remained (P for overall significance < 0.001). HR for T2D was 1.68 (95% CI: 1.13, 2.51) for the highest vs the lowest quartile of F₂-IsoPs. Moreover, this association appeared more pronounced among women with higher BMI. In summary, our study suggests that F₂-IsoPs could be of significance in T2D risk prediction among middle-aged and elderly women.

Natural Antioxidant Evaluation: A Review of Detection Methods

Antioxidants have drawn the attention of the scientific community due to being related to the prevention of various degenerative diseases. The antioxidant capacity has been extensively studied in vitro, and different methods have been used to assess its activity. However, the main issues related to studying natural antioxidants are evaluating whether these antioxidants demonstrate a key role in the biological system and assessing their bioavailability in the organism. The majority of outcomes in the literature are controversial due to a lack of method standardization and their proper application. Therefore, this study aims to compile the main issues concerning the natural antioxidant field of study, comparing the most common in vitro methods to evaluate the antioxidant activity of natural compounds, demonstrating the antioxidant activity in biological systems and the role of the main antioxidant enzymes of redox cellular signaling and explaining how the bioavailability of bioactive compounds is evaluated in animal models and human clinical trials.

Lipid peroxidation biomarkers associated with height and obesity measures in the opposite direction in women

OBJECTIVE

This study aimed to investigate whether and how lipid peroxidation markers are associated with height and obesity measures.

METHODS

In two independent samples of women (Study 1: n = 1,005; Study 2: n = 1,158), systemic levels of lipid peroxidation were assessed by urinary markers F₂ -isoprostanes (F₂ -IsoPs) and its major metabolite (F₂ -IsoP-M), with gas chromatography/negative ion chemical ionization mass spectrometry assays. Anthropometric parameters were directly measured and genetically estimated, and they were used in the primary analysis and in a Mendelian randomization analysis in relation to lipid peroxidation, respectively, with general linear models.

RESULTS

After adjusting for potential confounders, it was found that measured adult height was inversely associated with levels of F₂ -IsoPs (β = -0.89, p < 0.001) and F₂ -IsoP-M (β = -0.71, p = 0.003), whereas obesity measures were positively associated with F₂ -IsoP-M (β = 1.81, p < 0.001 for BMI; and β = 0.77, p < 0.001 for waist circumference). Results were consistent between the two study samples. The opposite associations were further replicated when using genetically determined measures of height and obesity in the Mendelian randomization analysis. Moreover, analyses mutually adjusted for height and obesity measures suggested that these associations were independent of one another.

CONCLUSIONS

This study, for the first time, to our knowledge, reveals that a shared biological process (lipid peroxidation) is associated with both height and obesity measures but in the opposite direction.