Biomarker Of Oxidative Damage Research Articles

Associations between volatile organic compounds exposure and multiple oxidative damage biomarkers: Method development, human exposure, and application for e-waste pollution prediction

Atmospheric monitoring studies reveal substantial health risks from exposure to volatile organic compounds (VOCs) for workers and nearby children in e-waste recycling areas (ERA), yet internal exposure risks are seldom examined. To address this, we developed a method to simultaneously analyze 12 urinary VOC metabolites (mVOCs) and oxidative damage biomarkers (ODBs) in workers and children from ERA and general adults from control areas using ultrahigh performance liquid chromatography coupled with quadrupole/orbitrap high-resolution mass spectrometry (UPLC-Orbitrap-HRMS). The results showed that e-waste workers exhibited significantly higher levels of VOC exposure and ODBs than e-waste children and control adults. Exceeding 91.1 %, 69.1 %, 20.8 %, 19.7 %, and 3.26 % of e-waste workers faced non-carcinogenic risk from exposure to acrolein, acrylonitrile, acrylamide, 1,3-butadiene, and 1,2-dichloroethane, respectively. The weighted quantile sum, quantile g-computation, and Bayesian kernel machine regression models consistently indicated significant positive associations between these VOC mixtures and cholesterol ODB levels (i.e., glycocholic acid, cholic acid, and glycochenodeoxycholic acid), highlighting the necessity for improved protective measures for occupational workers. Interestingly, cholesterol ODBs significantly mediated the association between VOCs exposure and nucleic acid ODBs, accounting for 12.0–26.0 % of the association with 8-hydroxy-2′-deoxyguanosine (an oxidative DNA damage biomarker) and 25.4–53.4 % with 8-hydroxyguanosine (an oxidative RNA damage biomarker). This suggests that cholesterol ODBs potentially serve as better indicators of health risks from VOC exposure than nucleic acid ODBs. Additionally, the combination of mVOCs and ODBs (Mean AUC: 0.906, ACC: 0.821) as exposure fingerprints outperformed either mVOCs (Mean AUC: 0.878, ACC: 0.802) or ODBs (Mean AUC: 0.843, ACC: 0.768) alone in predicting the presence of e-waste pollution, underscoring the importance of integrating exposure and effect biomarker fingerprints to accurately capture e-waste pollution characteristic. Our findings offer a novel approach for screening e-waste pollution in unknow e-waste recycling sites and provide a foundation for developing high-precision prediction models for other polluting industries.

Evidence of Oxidative Stress as a Mechanism of Pharmaceutical-Induced Toxicity in Amphibians

Amphibians, which are essential components of ecosystems, are susceptible to pharmaceutical contamination, a phenomenon of increasing concern owing to the widespread consumption and detection of pharmaceutical compounds in environmental matrices. This review investigates oxidative stress (OS) as the primary mechanism of drug toxicity in these organisms. The evidence gathered reveals that various pharmaceuticals, from antibiotics to anesthetics, induce OS by altering biomarkers of oxidative damage and antioxidant defense. These findings underscore the deleterious effects of pharmaceuticals on amphibian health and development and emphasize the necessity of incorporating OS biomarkers into ecotoxicological risk assessments. Although further studies on diverse amphibian species, drug mixtures, and field studies are required, OS biomarkers offer valuable tools for identifying sublethal risks. Furthermore, the development of more refined OS biomarkers will facilitate the early detection of adverse effects, which are crucial for protecting amphibians and their ecosystems. Ultimately, this review calls for continued research and mitigation strategies to safeguard biodiversity from pharmaceutical contamination.

Assessing the effects of cadmium on antioxidant enzymes and histological structures in rainbow trout liver and kidney

Cadmium contamination in aquatic environments poses severe risks to aquatic organisms, particularly fish, where cadmium accumulation in tissues can lead to compromised organ functionality and reproductive issues. The present study aimed to assess the effects of cadmium (Cd) exposure on key biomarkers of oxidative stress, DNA damage, apoptosis, and enzyme activity in the liver and kidney tissues of rainbow trout (Oncorhynchus mykiss). Specifically, the study measured 8-hydroxy-2-deoxyguanosine (8-OHdG) levels, caspase-3 activation, acetylcholinesterase (AChE) activity, and oxidative stress indicators (ONOO−, MDA, GSH, SOD, and CAT) following exposure to three Cd concentrations (1, 3, and 5 mg/L) over three time points (24, 48, and 96 h). Tissue samples were collected post-exposure, and the analysis revealed a significant decrease in MDA levels in both tissues. GSH concentrations declined with prolonged exposure, while SOD activity increased, indicating a response to oxidative stress, contrasted by a reduction in CAT activity. An initial increase in ONOO− levels was observed at 24 h, followed by a subsequent decrease at the 48 and 96 h marks. These results suggest that cadmium induces oxidative stress in the liver and kidney tissues of fish. Cadmium exposure also significantly elevated 8-OHdG levels, signaling DNA damage, and increased caspase-3 activity, indicative of apoptosis, across all doses and time points (p < 0.05). The histological examination of liver and kidney showed tissue injury. Additionally, a negative correlation between AChE activity and exposure duration was noted, with prolonged exposure resulting in substantial AChE inhibition. Given the role of AChE in behavior regulation, these findings underscore the importance of exploring time-dependent, tissue-specific changes in AChE activity to further elucidate the mechanisms underlying cadmium-induced behavioral abnormalities.

Association of ambient ozone exposure with early cardiovascular damage among general urban adults: A repeated-measures cohort study in China

Longitudinal evidence of long-term ozone exposure on heart rate variability (HRV, an early indicator of cardiovascular damage) is lacking and the potential mechanism remains largely unclear. Our objectives were to evaluate the cross-sectional and longitudinal associations of ozone exposure with HRV alteration, and the potential roles of protein carbonyl (PC, biomarker of oxidative protein damage) and transforming growth factor (TGF)-β1 in this association. This repeated-measures prospective study included 4138 participants with 6617 observations from the Wuhan-Zhuhai cohort. Ozone concentrations were estimated using a high temporospatial resolution model for each participant. HRV indices, PC, and TGF-β1 were also repeatedly measured. Cross-sectional and longitudinal relationships of ozone exposure with HRV alteration were evaluated by linear mixed model. Cross-sectionally, the strongest lag effect of each 10 ppb increment in short-term ozone exposure showed a 12.40 %, 8.47 %, 4.31 %, 8.03 %, 3.69 %, and 2.41 % decrement on very low frequency (VLF, lag 3 weeks), LF (lag 2 weeks), high frequency (HF, lag 0–7 days), total power (TP, lag 2 weeks), standard deviation of all normal-to-normal intervals (SDNN, lag 3 weeks), and square root of the mean squared difference between adjacent normal-to-normal intervals (lag 2 weeks), respectively. Longitudinally, each 10 ppb increment of annual average ozone was related with an annual change rate of −0.024 ms2/year in VLF, −0.009 ms2/year in LF, −0.013 ms2/year in HF, −0.014 ms2/year in TP, and −0.004 ms/year in SDNN. Mediation analyses indicated that PC mediated 20.77 % and 12.18 % of ozone-associated VLF and TP decline, respectively; TGF-β1 mediated 16.87 % and 27.78 % of ozone-associated VLF and SDNN reduction, respectively. Our study demonstrated that ozone exposure was cross-sectionally and longitudinally related with HRV decline in general Chinese urban adults, and oxidative protein damage and increased TGF-β1 partly mediated ozone exposure-related HRV reduction.

Piperine as an Herbal Alternative for the Prevention of Drug-Induced Liver Damage Caused by Paracetamol

Background/Objective: Hepatic drug intoxication is becoming increasingly common with the increasing use of chronic medications. Piperine has emerged as a promising alternative for protecting the liver against drug-induced injury. We evaluated the prophylactic effects of piperine in C57BL/6 mice with an acute liver injury induced by a paracetamol (APAP) overdose. Methods: Piperine was administered at a dose of 20 mg/kg (P20) or 40 mg/kg (P40) for eight consecutive days before the animals were exposed to a hepatotoxic dose of paracetamol (500 mg/kg). The animals were euthanized 3 h after the paracetamol overdose. Results: The prophylactic treatment with piperine (P20 and P40) maintained the levels of alanine aminotransferase (ALT) and the biomarkers of oxidative damage (TBARS and carbonylated proteins), which were statistically similar to those for the control group. The extent of hepatocyte necrosis and TNF-α (tumor necrosis factor-alpha) levels were lower than those in the group exposed to liver injury (APAP group). Piperine modulated the gene expression of CYP2E1 (cytochrome P4502E1) and the inflammasome pathway (NLRP3, CASP-1, IL-1β, and IL-18), which play a crucial role in the inflammatory response. In the P40 group, the degree of hepatic hyperemia was similar to that in the control group, as was the increase in metalloproteinase 9 (MMP-9) activity. Conclusion: Piperine has demonstrated beneficial and promising effects for the prevention of liver injury resulting from paracetamol-induced drug intoxication.

Apex carnivores coping with metal(loid) pollution and oxidative stress: biological and environmental drivers of variation in kidney of European brown bear

Induction of oxidative stress and the associated lipid peroxidation is a prevalent mechanism through which certain metal(loid)s exert nephrotoxic effects in mammals. Research on the toxic impacts of metal(loid)s in free-ranging large mammals at high trophic positions is exceedingly rare, yet crucial for understanding environmental exposure scenarios relevant to both human and animal risk assessment. Renal cortex tissues (N=457) of free-ranging brown bears (Ursus arctos) from the Dinara-Pindos population sampled in Croatia were analysed herein for toxic metal(loid)s and the underlying biological and environmental drivers of variation, with their time trend monitored during the 2009-2022 period. In 28 individuals from the 2021-2022 period, we additionally investigated associations between metal(loid)s and oxidative stress and damage biomarkers in renal cortex cells. The principal generalized linear models used to approximate variations in biomarkers of oxidative stress and damage included non-essential As, Cd, Pb, Tl and U, and essential Co, Cu, Fe and Zn. Age class and season of sampling had no impact on biomarker levels, except for lipid peroxidation, LP (April ↑). Age, sex (females ↑), body condition index (↓) and season of sampling significantly influenced metal(loid)s levels. Non-specific mammalian thresholds were crossed for Cd and Pb toxicity in 1-16% and 2% of population, respectively. Renal levels of metal(loid) did not exhibit a clear trend over the 13-year period. The levels found in this study were higher than in sympatric carnivorous and herbivorous species, but in line with findings in ursids worldwide. Potential adverse health effects from environmental exposure in brown bears may arise from disruption of oxidative balance, as evidence clearly indicated associated changes in catalase activity (↑), glutathione content (↑), LP (↓), reactive oxygen species (↓), total antioxidant capacity (↑) in the renal cortex due to the presence of the most toxicologically relevant Cd and Pb.

Methodologies for the detection and sequencing of the epigenetic-like oxidative DNA modification, 8-oxo-7,8-dihydroguanine.

The human genome is constantly threatened by endogenous and environmental DNA damaging agents that can induce a variety of chemically modified DNA lesions including 8-oxo-7,8-dihydroguanine (OG). Increasing evidence has indicated that OG is not only a biomarker for oxidative DNA damage but also a novel epigenetic-like modification involved in regulation of gene expression in mammalian cells. Here we summarize the recent progress in OG research focusing on the following points: (i) the mechanism of OG production in organisms and its biological consequences in cells, (ii) the accurate identification of OG in low-abundance genomes and complex biological backgrounds, (iii) the development of OG sequencing methods. These studies will be helpful for further understanding of the molecular mechanisms of OG-induced mutagenesis and its potential roles in human development and diseases such as cancer.

Oxidative damage biomarkers and antioxidant enzymes in saliva of patients with peri-implant diseases

Objectives8-hydroxydeoxyguanosine (8-OHdG) and Malondialdehyde (MDA) are commonly used as markers to evaluate oxidative DNA and Lipid damage in disorders including chronic inflammatory diseases. Superoxide dismutase (SOD) and glutathione peroxidase (GPx) protect tissues against oxidative injury from free oxygen radicals generated by various metabolic processes. The aim of this study was to evaluate 8-OHdG and MDA levels, and SOD and GPx activities in whole saliva of patients with peri-implant diseases.Materials and methodsA cross-sectional study was conducted on a sum of 60 age gender balanced; peri-implantitis (n = 20), peri-mucositis (n = 20) and healthy (n = 20) individuals. Unstimulated whole saliva samples were collected and to determine the clinical condition of each subject; the plaque index (PI), gingival index (GI), peri-implant probing pocket depth (PIPD), peri-implant presence of bleeding on probing (BOP) (with/without suppuration) and radiographic signs of crestal bone loss (BL) were measured. The salivary 8-OHdG level was measured using the ELISA method. SOD, GPx activities and MDA levels were determined spectrophotometrically.ResultsA total of 60 individuals had evaluations of 318 implants. In comparison to the peri-mucositis and peri-implantitis groups, the healthy group had significantly lower PI and GI scores (p < 0.001). The PIPD value differed amongst the groups, with the peri-implantitis group having the highest value (p < 0.001). Compared to the peri-mucositis and control groups, the peri-implantitis group had a significantly higher BL score (p < 0.001 and p < 0.001, respectively). The peri-implantitis group showed a significantly higher 8-OHdG level (p < 0.001; p < 0.001 respectively) than the peri-mucositis and control groups. Compared to the peri-mucositis and control groups, the peri-implantitis group had a significantly higher MDA level (p < 0.001 and p < 0.001, respectively). The peri-implantitis group had a significantly higher SOD level (p < 0.001 and p < 0.001, respectively) in comparison to the peri-mucositis and control groups. There was no significant difference in GPx levels between the peri-mucositis and control groups (p > 0.05), while the peri-implantitis group had significantly lower GPx levels than the peri-mucositis and control groups (p < 0.001 and p < 0.001, respectively).ConclusionsElevated levels of oxidative stress in saliva may indicate the onset of pathological bone loss surrounding the implant and may be an indication of peri-implantitis.Clinical relevanceIn peri-implant diseases, changes may occur in the levels of 8-OHdG, MDA, SOD and GPx in saliva, which may lead to a deterioration in the oxidant/antioxidant balance.

Shifting Rhythms: A Systematic Review Exploring the Multifaceted Effects of Shift Work and Circadian Disruption on Employee Cardiovascular Health.

Shift work has long been studied as a contributing risk factor for cardiovascular disease. This study aims to provide a comprehensive summary of data regarding shiftwork and its impact on the cardiovascular system from the last decade. It explores the association of shift schedules with multiple aspects of cardiovascular disease and the physiological processesthat lead up to it. It also identifies gaps in current knowledge regarding the topic. Two hundred and sixty-eight articles were gathered from PubMed, Google Scholar, and Science Direct using relevant medical subject headings (MeSH) strategy and advanced search using keywords including 'Shift work,' 'Night shift,' 'Occupational health,' 'Circadian rhythm,' 'Cardiovascular disease,' 'Cardiovascular health.'The search was conducted in April and completed in May 2023. Systemic reviews, meta-analysis, cohort and cross-sectional studies from the last 10 years were included, and assessment of multiple systematic reviews (AMSTAR), Newcastle Ottawa, and Joanna Briggs Institute (JBI) tools were used, respectively, for quality assessment. A total of 14 articles were included in our review, including five systematic reviews and meta-analyses, six prospective cohort studies, and three cross-sectional studies. Each study reported a significant association between shift work with some aspect of cardiovascular disease.An increase in the risk of myocardial infarction, coronary heart disease, hypertension, atherosclerosis, and metabolic syndrome is reported. Circadian disruption, unhealthy diet, and emotional and physiological stress contribute to these effects. Oxidative damage and inflammatory biomarkers appear to play a role in this process, but more research is warranted for a deeper understanding of these changes. Despite an abundance of evidence pointing towards the short-term and long-term harm to shift workers' cardiovascular health, there is limited research regarding the policies that are needed to better monitor cardiovascular damage in employees. The focus needs to shift toward prevention-based policies and their efficacy in workplace settings.

OXY-SCORE and Volatile Anesthetics: A New Perspective of Oxidative Stress in EndoVascular Aneurysm Repair-A Randomized Clinical Trial.

An aortic aneurysm (AA) is a life-threatening condition. Oxidative stress may be a common pathway linking multiple mechanisms of an AA, including vascular inflammation and metalloproteinase activity. Endovascular aneurysm repair (EVAR) is the preferred surgical approach for AA treatment. During surgery, inflammation and ischemia-reperfusion injury occur, and reactive oxygen species (ROS) play a key role in their modulation. Increased perioperative oxidative stress is associated with higher postoperative complications. The use of volatile anesthetics during surgery has been shown to reduce oxidative stress. Individual biomarkers only partially reflect the oxidative status of the patients. A global indicator of oxidative stress (OXY-SCORE) has been validated in various pathologies. This study aimed to compare the effects of the main volatile anesthetics, sevoflurane and desflurane, on oxidative status during EVAR. Eighty consecutive patients undergoing EVAR were randomized into two groups: sevoflurane and desflurane. Plasma biomarkers of oxidative damage (protein carbonylation and malondialdehyde) and antioxidant defense (total thiols, glutathione, nitrates, superoxide dismutase, and catalase activity) were measured before surgery and 24 h after EVAR. The analysis of individual biomarkers showed no significant differences between the groups. However, the OXY-SCORE was positive in the desflurane group (indicating a shift towards antioxidants) and negative in the sevoflurane group (favoring oxidants) (p < 0.044). Compared to sevoflurane, desflurane had a positive effect on oxidative stress during EVAR. The OXY-SCORE could provide a more comprehensive perspective on oxidative stress in this patient population.

8624 Maternal ZIKV Infection Causes Oxidative Damage in Placenta of Both Female and Male Mice

Abstract Disclosure: V.M. Nascimento: None. I.S. Andrade: None. C.B. Andrade: None. R.S. Alves: None. R.P. Sousa: None. A.C. Valim: None. L.S. Dias: None. K.N. Fontes: None. I.F. Miranda: None. S.A. Coelho: None. L.B. Arruda: None. R.S. Fortunato: None. T.M. Ortiga-Carvalho: None. The placenta is a maternal-fetal organ with nutritional, exchanging, hormonal and protecting functions that are vital for fetal growth and development during gestation. However, these functions can be disturbed by vertically transmitted pathogens such as Zika virus (ZIKV). In 2015, ZIKV was responsible for an increasing number of newborns with congenital abnormalities in Brazil, known as Congenital Zika Syndrome (CZS). Nonetheless, the extension of ZIKV infection in the placenta, leading to CZS, is still unclear. It is known that ZIKV causes oxidative stress in trophoblasts. However, no one has ever studied placental oxidative stress caused by ZIKV infection in vivo. Here, we investigated whether maternal ZIKV infection could cause sex-specific oxidative stress in murine placenta. At gestational day (GD)12.5, pregnant mice (C57BL/6; 8-12 weeks old) were infected with ZIKV-BRPE243 (5x107 PFU; ZIKV group, n=22) or Mock (supernatants of noninfected C6/36 cells; control group, n=28). At GD18.5, c-section was performed and maternal spleens, placentas, fetuses and fetal brains were collected. We measured placental carbonylated protein levels (n=7), by 2D OxyBlot, nitrotyrosine residues (n=5), by immunohistochemistry, reduced thiol content (n=9), total superoxide dismutase (SOD; n=9) and total glutathione peroxidase (GPx; n=9) activities, by spectrophotometry. Data were analyzed by unpaired Student’s t test and Two-Way ANOVA with Tukey’s post test and represented as mean±SEM. ZIKV infection increased maternal spleen weight (p&amp;lt;0.0001) and decreased both female (p=0.0429) and male (p=0.0171) placental weight. Although placental weights were affected by the infection, female and male fetal weight and fetal crown-rump length were not changed. Conversely, maternal ZIKV infection increased only female fetal brain weight (p=0.0028). Moreover, we found that ZIKV infection increased nitrotyrosine residues in the placental labyrinth region of both female (p&amp;lt;0.0001) and male (p=0.0007) fetuses. Meanwhile, nitrotyrosine residues were increased by the infection only in the placental junctional zone of female fetuses (p=0.0131). Although ZIKV increased this oxidative damage biomarker, placental carbonylated protein levels were not changed by the infection in both sexes. Also, reduced thiol content and total SOD and GPx activities were not affected. Together, our data show that maternal ZIKV infection caused oxidative stress in both placental regions of female and male fetuses, as we saw that ZIKV increased oxidative damage, although antioxidant defenses were not changed by the infection, at least at term (GD18.5). ZIKV infection may have disturbed placental growth, as we found that placental weight was decreased in both sexes. Moreover, we believe that the increase in the female fetal brain weight could be a suggestive feature of cerebral edema or hydrocephalus. Presentation: 6/2/2024

8624 Maternal ZIKV Infection Causes Oxidative Damage in Placenta of Both Female and Male Mice

Abstract Disclosure: V.M. Nascimento: None. I.S. Andrade: None. C.B. Andrade: None. R.S. Alves: None. R.P. Sousa: None. A.C. Valim: None. L.S. Dias: None. K.N. Fontes: None. I.F. Miranda: None. S.A. Coelho: None. L.B. Arruda: None. R.S. Fortunato: None. T.M. Ortiga-Carvalho: None. The placenta is a maternal-fetal organ with nutritional, exchanging, hormonal and protecting functions that are vital for fetal growth and development during gestation. However, these functions can be disturbed by vertically transmitted pathogens such as Zika virus (ZIKV). In 2015, ZIKV was responsible for an increasing number of newborns with congenital abnormalities in Brazil, known as Congenital Zika Syndrome (CZS). Nonetheless, the extension of ZIKV infection in the placenta, leading to CZS, is still unclear. It is known that ZIKV causes oxidative stress in trophoblasts. However, no one has ever studied placental oxidative stress caused by ZIKV infection in vivo. Here, we investigated whether maternal ZIKV infection could cause sex-specific oxidative stress in murine placenta. At gestational day (GD)12.5, pregnant mice (C57BL/6; 8-12 weeks old) were infected with ZIKV-BRPE243 (5x107 PFU; ZIKV group, n=22) or Mock (supernatants of noninfected C6/36 cells; control group, n=28). At GD18.5, c-section was performed and maternal spleens, placentas, fetuses and fetal brains were collected. We measured placental carbonylated protein levels (n=7), by 2D OxyBlot, nitrotyrosine residues (n=5), by immunohistochemistry, reduced thiol content (n=9), total superoxide dismutase (SOD; n=9) and total glutathione peroxidase (GPx; n=9) activities, by spectrophotometry. Data were analyzed by unpaired Student’s t test and Two-Way ANOVA with Tukey’s post test and represented as mean±SEM. ZIKV infection increased maternal spleen weight (p&amp;lt;0.0001) and decreased both female (p=0.0429) and male (p=0.0171) placental weight. Although placental weights were affected by the infection, female and male fetal weight and fetal crown-rump length were not changed. Conversely, maternal ZIKV infection increased only female fetal brain weight (p=0.0028). Moreover, we found that ZIKV infection increased nitrotyrosine residues in the placental labyrinth region of both female (p&amp;lt;0.0001) and male (p=0.0007) fetuses. Meanwhile, nitrotyrosine residues were increased by the infection only in the placental junctional zone of female fetuses (p=0.0131). Although ZIKV increased this oxidative damage biomarker, placental carbonylated protein levels were not changed by the infection in both sexes. Also, reduced thiol content and total SOD and GPx activities were not affected. Together, our data show that maternal ZIKV infection caused oxidative stress in both placental regions of female and male fetuses, as we saw that ZIKV increased oxidative damage, although antioxidant defenses were not changed by the infection, at least at term (GD18.5). ZIKV infection may have disturbed placental growth, as we found that placental weight was decreased in both sexes. Moreover, we believe that the increase in the female fetal brain weight could be a suggestive feature of cerebral edema or hydrocephalus. Presentation: 6/2/2024

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 60mg/kg, orally, respectively). QU and NAC (with doses of 50, 100, 200mg/kg), and their combination were administered, along with a standard therapy (metoclopramide; MET 2mg/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.

Oxidative stress-related biomarkers as promising indicators of inflammatory bowel disease activity: A systematic review and meta-analysis

Oxidative stress is believed to play an important role in the pathogenesis of inflammatory bowel disease (IBD), specifically Crohn's disease (CD) and ulcerative colitis (UC). This meta-analysis aimed to identify and quantify the oxidative stress-related biomarkers in IBD and their associations with disease activity. We systematically searched Ovid MEDLINE, Ovid Embase, and Web of Science databases, identifying 54 studies for inclusion. Comparisons included: (i) active IBD versus healthy controls; (ii) inactive IBD versus healthy controls; (iii) active CD versus inactive CD; and (iv) active UC versus inactive UC. Our analysis revealed a significant accumulation of biomarkers of oxidative damage to biomacromolecules, coupled with reductions in various antioxidants, in both patients with active and inactive IBD compared to healthy controls. Additionally, we identified biomarkers that differentiate between active and inactive CD, including malondialdehyde, Paraoxonase 1, catalase, albumin, transferrin, and total antioxidant capacity. Similarly, levels of Paraoxonase 1, erythrocyte glutathione peroxidase, catalase, albumin, transferrin, and free thiols differed between active and inactive UC. Vitamins and carotenoids also emerged as potential disease activity biomarkers for CD and UC, but their intake should be monitored to obtain meaningful results. These findings emphasize the involvement of oxidative stress in the pathogenesis of IBD and highlight the potential of oxidative stress-related biomarkers as a minimally invasive and additional tool for monitoring the activity of IBD.

Haemolysis overestimates plasma oxidative stress biomarkers in free-ranging roe deer

Quantifying oxidative stress has garnered extensive interest in evolutionary ecology and physiology since proposed as a mediator of life histories. However, while the theoretical framework of oxidative stress ecology is well-supported by laboratory-based studies, results obtained in wild populations on oxidative damage and antioxidant biomarkers have shown inconsistent trends. We propose that red blood cell lysis could be a source of bias affecting measurements of oxidative stress biomarkers, distorting the conclusions drawn from them. Using an experimental approach consisting of enriching plasma from roe deer with lysed red blood cells, we show that the values of commonly used oxidative stress biomarkers linearly increase with the degree of haemolysis – assayed by haemoglobin concentration. This result concerns oxidized proteins (carbonyls) and lipids (TBARS), as well as enzymatic (superoxide dismutase) and non-enzymatic (trolox assay, OXY assay) antioxidant markers. Based on 707 roe deer blood samples collected in the field, we next show that the occurrence of haemolysis in plasma samples is negatively related to age. Finally, we illustrate that considering the variance explained by age-related haemolysis improves explanatory models for inter-individual variability in plasma oxidative stress biomarkers, without substantially altering the estimates of the parameters studied here. Our results raise the question of the veracity of the conclusions if the degree of haemolysis in plasma is not considered in animal models such as roe deer, for which the occurrence and severity of haemolysis vary according to individual characteristics. We recommend measuring and controlling for the degree of haemolysis be considered in future studies that investigate the causes and consequences of oxidative stress in ecophysiological studies.

Enhancing ocular protection against UVB: The role of irigenin in modulating oxidative stress and apoptotic pathways In Vivo

Oxidative damage contributes to age-related macular degeneration. Irigenin possesses diverse pharmacologic properties, including antioxidative and antiapoptotic effects. Our in vivo experiments indicated that irigenin mitigates UVB-induced histopathologic changes and oxidative DNA damage. Histologic analyses and TUNEL staining revealed that this compound dose-dependently ameliorated UVB-induced retinal damage and apoptosis. Furthermore, irigenin substantially reduced the level of 8-hydroxyguanosine, a biomarker of UVB-induced oxidative DNA damage. We further explored the molecular mechanisms that mediate the protective effects of irigenin. Our findings suggested that UVB-induced generation of ROS disrupts the stability of the mitochondrial membrane, activating intrinsic apoptotic pathways; the underlying mechanisms include the release of cytochrome c, activation of caspase-9 and caspase-3, and subsequent degradation of PARP-1. Notably, irigenin reversed mitochondrial disruption and apoptosis. It also modulated the Bax and Bcl-2 expression but influenced the mitochondrial apoptotic pathways. Our study highlights the role of the Nrf2 pathway in mitigating the effects of oxidative stress. We found that UVB exposure downregulated, but irigenin treatment upregulated the expression of Nrf2 and antioxidant enzymes. Therefore, irigenin activates the Nrf2 pathway to address oxidative stress. In conclusion, irigenin exhibits protective effects against UVB-induced ocular damage, evidenced by the diminution of histological alterations. It mitigates oxidative DNA damage and apoptosis in the retinal tissues by modulating the intrinsic apoptotic pathways and the AIF mechanisms. Furthermore, irigenin effectively reduces lipid peroxidation, enhancing the activity of antioxidant enzymes by stimulating the Nrf2 pathway. This protective mechanism underscores the potential benefit of irigenin in combating UVB-mediated ocular damage.

8-OxodG: A Potential Biomarker for Chronic Oxidative Stress Induced by High-LET Radiation.

Oxidative stress-mediated biomolecular damage is a characteristic feature of ionizing radiation (IR) injury, leading to genomic instability and chronic health implications. Specifically, a dose- and linear energy transfer (LET)-dependent persistent increase in oxidative DNA damage has been reported in many tissues and biofluids months after IR exposure. Contrary to low-LET photon radiation, high-LET IR exposure is known to cause significantly higher accumulations of DNA damage, even at sublethal doses, compared to low-LET IR. High-LET IR is prevalent in the deep space environment (i.e., beyond Earth's magnetosphere), and its exposure could potentially impair astronauts' health. Therefore, the development of biomarkers to assess and monitor the levels of oxidative DNA damage can aid in the early detection of health risks and would also allow timely intervention. Among the recognized biomarkers of oxidative DNA damage, 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-OxodG) has emerged as a promising candidate, indicative of chronic oxidative stress. It has been reported to exhibit differing levels following equivalent doses of low- and high-LET IR. This review discusses 8-OxodG as a potential biomarker of high-LET radiation-induced chronic stress, with special emphasis on its potential sources, formation, repair mechanisms, and detection methods. Furthermore, this review addresses the pathobiological implications of high-LET IR exposure and its association with 8-OxodG. Understanding the association between high-LET IR exposure-induced chronic oxidative stress, systemic levels of 8-OxodG, and their potential health risks can provide a framework for developing a comprehensive health monitoring biomarker system to safeguard the well-being of astronauts during space missions and optimize long-term health outcomes.

The particle effect: comparative toxicity of chlorpyrifos in combination with microplastics and phytoplankton particles in mussel

Lately, the role of microplastics (MP) as vectors for dissolved contaminants and as vehicle for their transfer to aquatic organisms has received attention. Similarly to MP, other inorganic and organic particles may act as passive samplers. However, limited comparative knowledge exists at this respect. In the present study we have comparatively investigated the risk for mussel of MP and the pesticide chlorpyrifos (CPF) alone and in combination with MP and phytoplankton particles of microalgae (MP-CPF and MA-CPF, respectively). We selected MP and microalgae of similar size to expose mussel to the same volume of particles (≈1.5 mm3L−1 ≈ equivalent to 1.5 mg MP L−1) and the same concentration of contaminant (CPF, 7.6 μg L−1). MP were virgin HDPE microparticles (≤10 μm) while the microalgae species was Isochrisis galbana (4–8 μm). Mussels were exposed for 21 days to MP, CPF, MP-CPF and MA-CPF. Then, a suite of neurotoxicity, oxidative stress and oxidative damage biomarkers were measured in samples collected at day 7 and 21. Additionally, these biochemical markers were assessed in an integrated manner with others measured at physiological, immune and cell component level in the same organisms, previously published. Overall, MP did not elicit significant alterations on the majority of parameters measured. In contrast, mussels exposed to CPF, MA-CPF and MP-CPF showed evidence of neurotoxicity and oxidant imbalance at day 7, added to a detrimental physiological condition and immune imbalance at day 21. At the latter time MP-CPF mussels showed greater alterations than CPF or MA-CPF mussels. This suggested a synergistic toxicity of MP combined with CPF greater than that produced by the contaminants alone (MP or CPF) or by MA combined with CPF.

Cross-sectional and longitudinal associations of PAHs exposure with serum uric acid and hyperuricemia among Chinese urban residents: The potential role of oxidative damage

A few studies found polycyclic aromatic hydrocarbons (PAHs) were associated with serum uric acid (SUA) or hyperuricemia (HUA). However, the longitudinal study is vacant, and the underlying mechanisms remain unclear. We aimed to assess the cross-sectional and longitudinal associations of urinary PAHs metabolites with SUA levels and HUA risk, and explore the mediating effects of oxidative stress and inflammation. 10 urinary mono-hydroxylated PAHs metabolites and SUA levels were measured among 4047 Chinese urban residents at baseline and 1496 individuals at 6-year follow-up. Biomarkers of oxidative damage and inflammation in urine/plasma were determined at baseline. We adopted generalized linear mixed models and logistic regression to assess the associations of PAHs metabolites with SUA and HUA, weighted quantile sum regression and adaptive elastic net regression to evaluate the overall effects of multi-PAHs mixture, and mediation analysis to estimate the mediating roles of the biomarkers. In the cross-sectional study, each 1-unit increase in the ln-transformed values of 2-OHNa, 2-OHFlu, 4-OHPh, 9-OHPh, 3-OHPh, 2-OHPh, ΣOHNa, ΣOHPh, and ΣOHPAHs was associated with a 4.10-, 3.90-, 6.42-, 7.33-, 4.85-, 5.43-, 4.47-, 7.67-, and 5.22-μmol/L increase in SUA, respectively. Meanwhile, each 1-unit increase in the ln-transformed values of 1-OHNa, 2-OHNa, 4-OHPh, 9-OHPh, 3-OHPh, 2-OHPh, ΣOHNa, ΣOHPh, and ΣOHPAHs was associated with a 17, 14, 15, 22, 14, 19, 18, 27, and 21% increment in HUA risk, respectively. After 6 years, individuals with persistent high level of 9-OHPh had a 12.5 μmol/L increase in SUA compared with those with persistent low level. The overall effects of multi-PAHs mixture on SUA and HUA remain positive. 8-hydroxy-deoxyguanosine mediated the associations of PAHs metabolites with SUA and HUA, and the mediated proportion ranged from 5.39% to 15.34%. PAHs exposure was associated with the elevated SUA levels and increased HUA risk, and oxidative DNA damage may be one of the underlying mechanisms.

Toxicological insight of metiram: immuno-oxidative, neuro-behavioral, and hemato-biochemical changes during acute exposure of Nile tilapia (Oreochromis niloticus)

BackgroundThe inappropriate use of pesticides including fungicides creates severe biological hazards that can endanger fish health and impede sustainable aquaculture.ObjectiveThis study investigated the negative impacts of metiram (MET), a fungicide on the health status of Nile tilapia (Oreochromis niloticus) for a 96-hour duration as an acute exposure in a static renewal system.MethodsThree hundred fish (average body weight: 37.50 ± 0.22 g) were assigned into six groups (50 fish/group) with five replicates (10 fish/replicate). Fish were exposed to various six concentrations (0, 1.5, 3, 4.5, 6, and 7.5 mg/L) of MET as a water exposure to for 96-hour without water exchange. The fish’s behavior, clinical signs, and mortalities were documented every day of the exposure period. Additionally, MET’s impact on blood profile, stress biomarkers, hepato-renal functions, immune-antioxidant status, and brain biomarker were closely monitored.ResultsThe lethal concentration (LC50) of MET estimated using Finney’s probit technique was 3.77 mg/L. The fish’s behavior was severely impacted by acute MET exposure, as clear by an increase in surfacing, loss of equilibrium, unusual swimming, laterality, abnormal movement, and a decline in aggressive behaviors. The survivability and hematological indices (white and red blood cell count, differential white blood cell count, hematocrit value, and hemoglobin) were significantly reduced in a concentration-dependent manner following MET exposure. Acute exposure to MET (1.5–7.5 mg/L) incrementally increased stress biomarkers (nor-epinephrine, cortisol, and glucose), lipid peroxides (malondialdehyde), and brain oxidative DNA damage biomarker (8-hydroxy-2-deoxyguanosine). A hepato-renal dysfunction by MET exposure (4.5–7.5 mg/L) was evidenced by the significant increase in the alanine and aspartate aminotransferases and creatinine values. Moreover, a substantial decline in the immune parameters (lysozyme, complement 3, serum bactericidal activity, and antiprotease activity) and antioxidant variables (total antioxidant capacity, superoxide dismutase, and glutathione peroxidase) resulted from acute MET exposure.ConclusionAccording to these findings, the 96-hour LC50 of MET in Nile tilapia was 3.77 mg/L. MET exposure triggered toxicity in Nile tilapia, as seen by alterations in fish neuro-behaviors, immune-antioxidant status, hepato-renal functioning, and signifying physiological disturbances. This study emphasizes the potential ecological dangers provoked by MET as an environmental contaminant to aquatic systems. However, the long-term MET exposure is still needed to be investigated.