Xylene Induces Oxidative Stress and Mitochondria Damage in Isolated Human Lymphocytes

An integrative exploration of environmental stressors on the microbiome-gut-brain axis and immune mechanisms promoting neurological disorders

The microbiome-gut-brain axis is altered by environmental stressors such as heat, diet, and pollutants as well as microbes in the air, water, and soil. These stressors might alter the host's microbiome and symbiotic relationship by modifying the microbial composition or location. Compartmentalized mutualistic microbes promote the beneficial interactions in the host leading to circulating metabolites and hormones such as insulin and leptin that affect inter-organ functions. Inflammation and oxidative stress induced by environmental stressors may alter the composition, distribution, and activities of the microbes in the microbiomes such that the resultant metabolite and hormone changes are no longer beneficial. The microbiome-gut-brain axis and immune adverse changes that may accompany environmental stressors are reviewed for effects on innate and adaptive immune cells, which may make host immunity less responsive to pathogens and more reactive to self-antigens. Cardiovascular and fluid exchanges to organs might adversely alter organ functionality. Organs, especially the brain, need a consistent supply of nutrients and clearance of debris; disruption of these exchanges by stressors, and involvement of gut microbiome are discussed regarding neural dysfunctions with Alzheimer's disease, autistic spectrum disorders, viral infections, and autoimmune diseases. The focus of this review includes the manner in which environmental stressors may disrupt gut microbiota leading to adverse immune and hormonal influences on development of neuropathology related to hyperhomocysteinemia, inflammation, and oxidative stress, and how certain therapeutics may be beneficial. Strategies are explored to lessen detrimental effects of environmental stressors on central and peripheral health navigated toward (1) understanding neurological disorders and (2) promoting environmental and public health and well-being.

Altered oxidative stress and antioxidant biomarkers concentrations in pregnant individuals exposed to oil and gas sites in Northeastern British Columbia

Northeastern British Columbia is a region of prolific unconventional oil and gas (UOG) activity. UOG activity can release volatile organic compounds (VOCs) which can elevate oxidative stress and disrupt antioxidant activity in exposed pregnant individuals, potentially increasing the risk of adverse pregnancy outcomes. This study measured biomarkers of oxidative stress and antioxidant activity in pooled urine samples of 85 pregnant individuals living in Northeastern British Columbia, to analyze associations between indoor air VOCs, oil and gas well density and proximity metrics, and biomarker concentrations. Concentrations of catalase, superoxide dismutase (SOD), glutathione S-transferase, total antioxidant capacity, 6-hydroxymelatonin sulfate (aMT6s), malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG), and 8-isoprostane were measured using assay kits. Associations between exposure metrics and biomarker concentrations were determined using multiple linear regression models adjusted for biomarker-specific covariables. UOG proximity was associated with decreased SOD and 8-OHdG. Decreased 8-OHdG was associated with increased proximity to all wells. Decreased aMT6s were observed with increased indoor air hexanal concentrations. MDA was negatively associated with indoor air 1,4-dioxane concentrations. No statistically significant associations were found between other biomarkers and exposure metrics. Although some associations linked oil and gas activity to altered oxidative stress and antioxidant activity, the possibility of chance findings due to the large number of tests cannot be discounted. This study shows that living near UOG wells may alter oxidative stress and antioxidant activity in pregnant individuals. More research is needed to elucidate underlying mechanisms and to what degree UOG activity affects oxidative stress and antioxidant activity.

Mounting agents with low toxicity and with fast curing time for digital pathology in the intraoperative frozen section laboratory

AIMS

In intraoperative frozen tissue section laboratories (FS laboratories) conventional practice for mounting coverslips on tissue slides involves the use of xylene-based mounting agents, such as Pertex. However, toxic vapours pose a risk to biomedical laboratory scientists (BLS) and pathologists who handle the wet slides to provide fast and urgent diagnostic results to surgeons during operations. Our study aims to evaluate non-toxic mounting agents to substitute Pertex, preferably with a fast curing time suitable for the demands of the new digital era in pathology.

METHODS

Five non-toxic mounting agents were purchased and tested through six different protocols and compared to xylene-based Pertex as our gold standard. With light microscopy, tissue slides were quality assessed by BLS. Mounting agents, which were evaluated comparable to Pertex, were also evaluated by a pathologist, hence scanned digitally and re-evaluated.

RESULTS

The protocols for Eukitt UV, Eukitt UV R-1 and Eukitt UV R-2 had significantly more artefacts (bubbles) compared to gold standard Pertex (p<0.0001, p=0.004 and p<0.0001, respectively) and assessed inadequate as replacements. Neo-Mount and Tissue Mount were assessed applicable regarding quality, but curing times were long. Tek Select UV showed promising results in both quality and fast curing time (protocol was <2 min).

CONCLUSIONS

Toxic mounting agents need replacement to health guard professionals, and also digital pathology is revolutionising laboratories. A digitalized FS laboratory requires fast dry/cured slides for digital scanning. Therefore, a substitute for the FS laboratory should have the qualities of being non-toxic to handle and having a fast curing time, and a UV-based mounting agent may solve both requirements.

Guardians under Siege: Exploring Pollution's Effects on Human Immunity

Chemical pollution poses a significant threat to human health, with detrimental effects on various physiological systems, including the respiratory, cardiovascular, mental, and perinatal domains. While the impact of pollution on these systems has been extensively studied, the intricate relationship between chemical pollution and immunity remains a critical area of investigation. The focus of this study is to elucidate the relationship between chemical pollution and human immunity. To accomplish this task, this study presents a comprehensive review that encompasses in vitro, ex vivo, and in vivo studies, shedding light on the ways in which chemical pollution can modulate human immunity. Our aim is to unveil the complex mechanisms by which environmental contaminants compromise the delicate balance of the body's defense systems going beyond the well-established associations with defense systems and delving into the less-explored link between chemical exposure and various immune disorders, adding urgency to our understanding of the underlying mechanisms and their implications for public health.

Synthesis of Bio-Base Fluorescence Carbon Dots for Selective Detection of Tartrazine and Sunset Yellow in Food Samples

A green, economical and simple method for the preparation of water-soluble, high-fluorescent carbon quantum dots (CQDs) has been developed via hydrothermal process using pomelo peels as carbon source. The synthesized CQDs were characterized by transmission electron microscopy (TEM), X-ray diffraction(XRD), Fourier transform infrared spectroscopy (FTIR), UV - vis absorption spectra and fluorescence spectrophotometer. The results reveal that the as-prepared C-dots were spherical shape with an average diameter of 2.64 nm and emit bright blue photoluminescence (PL) with a quantum yield of approximately 3.63%. The surface of the C-dots was rich in hydroxyl groups and presented various merits including excellent photostability, low toxicity, and satisfactory solubility. Additionally, we found that two widely used synthetic food colorants, tartrazine and sunset yellow, could result in a strong fluorescence quenching of the C-dots, The possible mechanisms are caused by different ratios of inner filter and static quenching effects. According to this property, This study attempts to establish an analytical method for the determination of tartrazine and sunset yellow using carbon quantum dots as fluorescent probe. A linear relationship was found in the range of 0-100 µM tartrazine and sunset yellow with the detection limit(3σ/k) of 0.65 nM and 1.7 nM. The relative standard deviation (RSD) was 3.5% (tartrazine) and 3.0% (sunset yellow).This observation was further successfully applied for the determination of tartrazine and sunset yellow in food samples collected from local markets, and the recovery rates of the two ranges from 79% to 117.8 and 81 -103.5%, respectively. suggesting its great potential toward food routine analysis.

Environmental Chemical-Induced Reactive Oxygen Species Generation and Immunotoxicity: A Comprehensive Review

Significance: Reactive oxygen species (ROS), the reactive oxygen-carrying chemicals moieties, act as pleiotropic signal transducers to maintain various biological processes/functions, including immune response. Increased ROS production leads to oxidative stress, which is implicated in xenobiotic-induced adverse effects. Understanding the immunoregulatory mechanisms and immunotoxicity is of interest to developing therapeutics against xenobiotic insults. Recent Advances: While developmental studies have established the essential roles of ROS in the establishment and proper functioning of the immune system, toxicological studies have demonstrated high ROS generation as one of the potential mechanisms of immunotoxicity induced by environmental chemicals, including heavy metals, pesticides, aromatic hydrocarbons (benzene and derivatives), plastics, and nanoparticles. Mitochondrial electron transport and various signaling components, including NADH oxidase, toll-like receptors (TLRs), NF-κB, JNK, NRF2, p53, and STAT3, are involved in xenobiotic-induced ROS generation and immunotoxicity. Critical Issues: With many studies demonstrating the role of ROS and oxidative stress in xenobiotic-induced immunotoxicity, rigorous and orthogonal approaches are needed to achieve in-depth and precise understanding. The association of xenobiotic-induced immunotoxicity with disease susceptibility and progression needs more data acquisition. Furthermore, the general methodology needs to be possibly replaced with high-throughput precise techniques. Future Directions: The progression of xenobiotic-induced immunotoxicity into disease manifestation is not well documented. Immunotoxicological studies about the combination of xenobiotics, age-related sensitivity, and their involvement in human disease incidence and pathogenesis are warranted. Antioxid. Redox Signal. 40, 691-714.

Coniferyl ferulate alleviate xylene-caused hematopoietic stem and progenitor cell toxicity by Mgst2

Xylene exposure is known to induce toxicity in hematopoietic stem and progenitor cells (HSPCs), leading to bone marrow suppression and potential leukemogenesis. However, research on the gene expression profiles associated with xylene-induced toxicity in HSPCs, and effective therapeutic interventions, remains scarce. In our study, we employed single-cell RNA sequencing to capture the transcriptomic shifts within bone marrow HSPCs both prior to and following treatment with coniferyl ferulate (CF) in a mouse model of xylene-induced hematotoxicity. Subsequently, we pinpointed CF as a targeted agent using SPR-LC/MS analysis. This enabled us to confirm the link between the gene Mgst2 and specific cellular subtypes. Our data revealed that CF significantly countered the reduction of both monocyte and neutrophil progenitor cells, which are commonly affected by xylene toxicity. Through targeted analysis, we identified Mgst2 as a direct molecular target of CF. Notably, Mgst2 is preferentially expressed in neutrophil progenitor cells and is implicated in mitochondrial metabolic processes. By selectively inhibiting Mgst2 in bone marrow, we observed amelioration of xylene-induced hematotoxic effects. In summary, our findings suggest that coniferyl ferulate can mitigate the detrimental impact of xylene on hematopoietic stem and progenitor cells by targeting Mgst2, particularly within subpopulations of neutrophil progenitors. This discovery not only advances our comprehension of the cellular response of HSPCs to xenobiotic stressors like xylene but also identifies CF and Mgst2 as potential therapeutic targets for alleviating xylene-induced hematotoxicity.

Volatile organic compounds: A threat to the environment and health hazards to living organisms - A review

Volatile organic compounds (VOCs) are the organic compounds having a minimum vapor pressure of 0.13 kPa at standard temperature and pressure (293 K, 101 kPa). Being used as a solvent for organic and inorganic compounds, they have a wide range of applications. Most of the VOCs are non-biodegradable and very easily become component of the environment and deplete its purity. It also deteriorates the water quality index of the water bodies, impairs the physiology of living beings, enters the food chain by bio-magnification and degrades, decomposes and manipulates the physiology of living organisms. To unveil the adverse impacts of volatile organic compounds (VOCs) and their rapid eruption and interference in the living world, a review has been designed. This review presents an insight into the currently available VOCs, their sources, applications, sampling methods, analytic procedures, imposition on the health of aquatic and terrestrial communities and their contamination of the environment. Elaboration has been done on representation of toxicological effects of VOCs on vertebrates, invertebrates, and birds. Subsequently, the role of environmental agencies in the protection of environment has also been illustrated.

The association between oil spill cleanup-related total hydrocarbon exposure and diabetes

BACKGROUND

Although evidence suggests relationships between some crude oil components and glycemic dysregulation, no studies have examined oil spill-related chemical exposures in relation to type 2 diabetes mellitus (DM) risk. This study examined the relationship between total hydrocarbon (THC) exposure among workers involved in the 2010 Deepwater Horizon (DWH) oil spill and risk of DM up to 6 years afterward.

METHODS

Participants comprised 2660 oil-spill cleanup or response workers in the prospective GuLF Study who completed a clinical exam and had no self-reported DM diagnosis prior to the spill. Maximum THC exposure was estimated with a job-exposure matrix based on interview data and personal measurements taken during cleanup operations. We defined incident DM by self-reported physician diagnosis of DM, antidiabetic medication use, or a measured hemoglobin A1c value ≥ 6.5%. We used log binomial regression to estimate risk ratios (RRs) for DM across ordinal categories of THC exposure. The fully adjusted model controlled for age, sex, race/ethnicity, education, employment status, and health insurance status. We also stratified on clinical body mass index categories.

RESULTS

We observed an exposure-response relationship between maximum daily ordinal THC exposure level and incident DM, especially among overweight participants. RRs among overweight participants were 0.99 (95% CI: 0.37, 2.69), 1.46 (95% CI: 0.54, 3.92), and 2.11 (95% CI: 0.78, 5.74) for exposure categories 0.30-0.99 ppm, 1.00-2.99 ppm, and ≥3.00 ppm, respectively (ptrend = 0.03).

CONCLUSION

We observed suggestively increasing DM risk with increasing THC exposure level among overweight participants, but not among normal weight or obese participants.

Volatile organic compounds: A proinflammatory activator in autoimmune diseases

The etiopathogenesis of inflammatory and autoimmune diseases, including pulmonary disease, atherosclerosis, and rheumatoid arthritis, has been linked to human exposure to volatile organic compounds (VOC) present in the environment. Chronic inflammation due to immune breakdown and malfunctioning of the immune system has been projected to play a major role in the initiation and progression of autoimmune disorders. Macrophages, major phagocytes involved in the regulation of chronic inflammation, are a major target of VOC. Excessive and prolonged activation of immune cells (T and B lymphocytes) and overexpression of the master pro-inflammatory constituents [cytokine and tumor necrosis factor-alpha, together with other mediators (interleukin-6, interleukin-1, and interferon-gamma)] have been shown to play a central role in the pathogenesis of autoimmune inflammatory responses. The function and efficiency of the immune system resulting in immunostimulation and immunosuppression are a result of exogenous and endogenous factors. An autoimmune disorder is a by-product of the overproduction of these inflammatory mediators. Additionally, an excess of these toxicants helps in promoting autoimmunity through alterations in DNA methylation in CD4 T cells. The purpose of this review is to shed light on the possible role of VOC exposure in the onset and progression of autoimmune diseases.

Toxicological and Teratogenic Effect of Various Food Additives: An Updated Review

Scientific evidence is mounting that synthetic chemicals used as food additives may have harmful impacts on health. Food additives are chemicals that are added to food to keep it from spoiling, as well as to improve its colour and taste. Some are linked to negative health impacts, while others are healthy and can be ingested with little danger. According to several studies, health issues such as asthma, attention deficit hyperactivity disorder (ADHD), heart difficulties, cancer, obesity, and others are caused by harmful additives and preservatives. Some food additives may interfere with hormones and influences growth and development. It is one of the reasons why so many children are overweight. Children are more likely than adults to be exposed to these types of dietary intakes. Several food additives are used by women during pregnancy and breast feeding that are not fully safe. We must take specific precaution to avoid consuming dangerous compounds before they begin to wreak havoc on our health. This study is intended to understand how the preservatives induce different health problem in the body once it is consumed. This review focuses on some specific food additives such as sodium benzoate, aspartame, tartrazine, carrageenan, and potassium benzoate, as well as vitamin A. Long-term use of food treated with the above-mentioned food preservatives resulted in teratogenicity and other allergens, according to the study. Other health issues can be avoided in the future by using natural food additives derived from plants and other natural sources.

Blood serum levels of selected biomarkers of oxidative stress among printing workers occupationally exposed to low-levels of toluene and xylene

Printing workers (PWs) are exposed to a mixture of solvents, yet the health risks associated with such exposuer are unknown. This study aimed to compare the serum levels of selected biomarkers of oxidative stress among occupationally exposed PWs to low-level of toluene and xylenes and unexposed controls. Associations between levels of such biomarkers and occupational exposures to toluene and xylene were also investigated. Urinary levels of hippuric acid (HA) and methyl hippuric acids (MHAs) as exposure biomarkers of toluene and xylenes, respectively, and serum levels of oxidative stress biomarkers, including total antioxidant capacity (TAC), malondialdehyde (MDA), and the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), were measured among the 84 subjects, comprising 44 PWs and 40 unexposed subjects. Mean concentrations of urinary HA and MHAs of PWs showed a significant increase compared with the unexposed controls. Although levels of urinary biomarkers of exposure to toluene (HA) and xylenes (MHAs) were well below the biological exposure indices (BEIs; ACGHI), PWs presented significantly increased serum levels of MDA, and significantly decreased serum activities of SOD and GPx compared to the unexposed controls. However, for serum TAC and CAT activity, no significant difference was observed between the two groups. Correlation analyses indicated that urinary levels of HA and MHAs were positively correlated with MDA levels and negatively correlated with GPx and SOD. Our study suggested that the alterations evidenced in serum levels of MDA, SOD, and GPx could be involved in the oxidative stress caused by co-exposure to low levels of toluene and xylene. Further investigation is needed to clarify the effect of low-level occupational exposure to solvents among PWs.

Inhibition of scopolamine-induced memory and mitochondrial impairment by betanin

Mitochondrial dysfunction and oxidative stress are identified to contribute to the mechanisms responsible for the pathogenesis of Alzheimer's disease (AD). Scopolamine (SCO) as a potent drug for inducing memory and learning impairment is associated with mitochondrial dysfunction and oxidative stress. In AD clinical trials molecules with antioxidant properties have shown modest benefit. Betanin as a multifunctional molecule with powerful antioxidative properties may be effective in the treatment of neurodegenerative. Hence, this study was designed to investigate the possible therapeutic effect of betanin against SCO-induced AD on Wistar rats. SCO (1 mg/kg) was administrated intraperitoneally to induce the AD in Wistar rats. The rats were treated with betanin doses (25 mg/kg and 50 mg/kg) intraperitoneally for 9 consecutive days. At the end of the 9th day, the animals were subjected to behavioral examination such as novel object recognition and passive avoidance tests and killed to study the mitochondrial and histological parameters. The results showed attenuation of SCO-induced memory and learning impairment by betanin at 50 mg/kg dose. Also, mitochondrial toxicity parameters such as mitochondrial membrane potential collapse, mitochondrial swelling, decreased activity of succinate dehydrogenase, and reactive oxygen species (ROS) production were reversed by betanin (50 mg/kg) compared to the SCO group. In addition, the ameliorative effect of betanin against SCO was demonstrated in histopathological results of hippocampus. The present investigation established that the betanin ameliorates the SCO-induced memory impairments, tissue injuries, and mitochondrial dysfunction by reducing mitochondrial ROS, which may be due to the potent antioxidant action of betanin.

Differences in sensitivity of human lymphocytes and fish lymphocytes to polyvinyl chloride microplastic toxicity

Polyvinyl chloride (PVC) microplastics are emerging contaminants affecting biological wastewater treatment processes. So far, the toxicological investigation of PVC microplastics usually focused on the anaerobic and denitrifying bacteria. It seems that the primary lymphocytes isolated from peripheral blood are more sensitive than most other organ cell types in vitro; therefore, the aim of this study was to assess the cytotoxicity of PVC microplastic on human and fish blood lymphocytes as a useful ex vivo model for accelerated human toxicity studies. Using biochemical analyses, we showed human lymphocytes are more sensitive to toxic effects of PVC microplastic than fish lymphocytes. Our result showed that addition of PVC microplastic at 24, 48, and 96 μ g/ml for 3 h to human blood lymphocytes induced cytotoxicity. The PVC microplastic-induced cytotoxicity on human blood lymphocytes was associated with intracellular reactive oxygen species (ROS) formation, lysosomal membrane injury, mitochondrial membrane potential (MMP) collapse, depletion of glutathione, and lipid peroxidation. According to our results, PVC microplastic particles induce oxidative stress and organelle damage in human lymphocytes, while these significant alterations in toxicity parameters in PVC microplastic-treated fish lymphocytes were not observed. Finally, our findings suggest that human lymphocytes are more sensitive to PVC microplastic toxicity compared with fish lymphocytes.

Analysis of toxicity effects of delta-9-tetrahydrocannabinol on isolated rat heart mitochondria

Mitochondria have the main roles in myocardial tissue homeostasis, through providing ATP for the vital enzymes in intermediate metabolism, contractile apparatus and maintaining ion homeostasis. Mitochondria-related cardiotoxicity results from the exposure with illicit drugs have previously reported. These illicit drugs interference with processes of normal mitochondrial homeostasis and lead to mitochondrial dysfunction and mitochondrial-related oxidative stress. Cannabis consumption has been shown to cause ventricular tachycardia, to increase the risk of myocardial infarction (MI) and potentially sudden death. Here, we investigated this hypothesis that delta-9-tetrahydrocannabinol (Delta-9-THC) as a main cannabinoid found in cannabis could directly cause mitochondrial dysfunction. Cardiac mitochondria were isolated with mechanical lysis and differential centrifugation form rat heart. The isolated cardiac mitochondria were treated with different concentrations of THC (1, 5, 10, 50, 100 and 500 µM) for 1 hour at 37 °C. Then, succinate dehydrogenase (SDH) activity, mitochondrial swelling, reactive oxygen species (ROS) formation, mitochondrial membrane potential (MMP) collapse and lipid peroxidation were measured in the treated and nontreated isolated cardiac mitochondria. Our observation showed that THC did not cause a deleterious alteration in mitochondrial functions, ROS production, MMP collapse, mitochondrial swelling, oxidative stress and lipid peroxidation in used concentrations (5-100 µM), even in several tests, toxicity showed a decreasing trend. Altogether, the results of the current study showed that THC is not directly toxic in isolated cardiac mitochondria, and even may be helpful in reducing mitochondrial toxicity.

Linalool reverses benzene-induced cytotoxicity, oxidative stress and lysosomal/mitochondrial damages in human lymphocytes

Benzene exposure results in bone marrow suppression, leading to a decrease in the number of circulating white blood cells, an increased risk of chronic lymphocytic leukemia, acute myeloid leukemia and aplastic anemia. Since the mechanism of induction of benzene toxicity is due to active metabolites through cytochrome p450 enzymes and production of reactive oxygen species (ROS), we hypothesized that natural compound such linalool with anti-inflammatory/antioxidant properties could be effective in reducing its toxicity. Lymphocytes isolated from healthy individuals were simultaneously cotreated with different concentrations of LIN (10, 25 and 50 µM) and benzene (50 µM) for 4 h at 37 °C. After incubation, the toxicity parameters such cytotoxicity, ROS formation, lysosomal membrane integrity, mitochondria membrane potential (ΔΨm) collapse, oxidized/reduced glutathione (GSH/GSSG) and malondialdehyde (MDA) were analyzed using biochemical and flow cytometry evaluations. Our data showed that benzene (50 µM) induced a significant increase in cytotoxicity, ROS formation, mitochondrial membrane potential (MMP) collapse, lipid peroxidation and oxidative stress while LIN with antioxidant potential reversed the toxic effects of benzene on isolated human lymphocytes. Our results suggest that LIN reduces and reverses benzene-induced cytotoxicity, oxidative stress and lysosomal/mitochondrial damages in human lymphocyte. This study demonstrated that cotreatment of LIN with benzene can reduce several parameters indicative of oxidative stress. As such, LIN could represent a potential therapeutic agent in reducing certain aspects of benzene-induced toxicity.

Dietary flaxseed's protective effects on body tissues of mice after oral exposure to xylene

Xylene is a common pollutant in the environment that enters the body of animals and humans in various ways, but most often through the respiratory tract and adversely affects their overall health. However, xylene effects after oral exposure have not been sufficiently studied. This study aimed to investigate the effects of xylene exposure on the mouse organism and to identify possible beneficial effects of flaxseed on such exposure. Eighty mice were divided into four groups: control group C (basal diet + no xylene exposure), group X (oral exposure by 400 mg/kg/day xylene), group F (10% flaxseed supplementation of basal diet), and group XF (10% dietary flaxseed + oral exposure by xylene). Experimental trial took 14 days. Clinical examination, spectroscopic analysis of tissue aminotransferases, total lactate dehydrogenase (TLDH), and acetylcholinesterase (AchE) activities, electrophoretic analysis of LDH isoenzymes, western blot and immunohistochemical analysis of apoptosis as well as routine histology of the kidneys and jejunum, and transmission electron microscopy of the liver were performed. Marked restlessness in group X and high weight losses in mice of all groups were recorded during the experiment. Xylene promoted apoptosis (caspase-3 expression) without causing marked structural changes in the liver and jejunum, although renal cortex structure was affected adversely. In the brain, liver, and kidney of mice, xylene increased levels of liver transaminases, LDH, and decreased AchE activities, reflecting cell membrane damage. Flaxseed feeding improved animal behaviour, leakage of enzymes and prevented selected tissue toxic damage induced by xylene by protecting cell membrane integrity and fluidity and by suppressing apoptosis. These results point at the protective effect of flaxseed consumption on mice.

Buckwheat, rooibos, and vitex extracts can mitigate adverse effects of xylene on ovarian cells in vitro

This study examines whether selected functional food and medicinal plants can mitigate the adverse effects of xylene on ovarian cells. The influences of xylene (0, 10, 100, or 1000 ng/mL), buckwheat (Fagopyrum esculentum), rooibos (Aspalathus linearis), vitex (Vitex agnus-castus), extracts (10 μg/mL each), and a combination of xylene with these plant additives on cultured porcine ovarian granulosa cells are compared. Cell viability, proliferation (PCNA accumulation), apoptosis (accumulation of bax), and release of progesterone (P4) and estradiol (E2) were analyzed by the trypan blue tests, quantitative immunocytochemistry, and enzyme-linked immunosorbent assays, respectively. Xylene suppressed all measures of ovarian cell function. Rooibos prevented all of xylene's effects, whereas buckwheat and vitex prevented four of five of the analyzed effects (buckwheat prevented xylene influence on viability, PCNA, bax, and E2; vitex prevented xylene action on viability, PCNA, and P4 and E2). These observations show that xylene has the potential to suppress ovarian cell functions, and that buckwheat, rooibos, and vitex can mitigate those effects, making them natural protectors against the adverse effects of xylene on ovarian cells.

Health examination results and work environment factors affecting urinary 8-hydroxy-2'-deoxyguanosine levels

OBJECTIVE

Oxidative stress is considered to cause lifestyle-related diseases, including cancer. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) is widely analyzed as an oxidative stress marker. We extensively scrutinized the relationships between 8-OHdG levels and lifestyle choices as carcinogenic factors.

METHODS

In this study, we investigated health examination results and working conditions affecting urinary 8-OHdG levels in 503 male workers.

RESULTS

The urinary 8-OHdG level was positively associated with high blood sugar and leanness in smokers. In addition, urinary 8-OHdG tended to increase with organic solvent or hydrochloric acid exposure, as well as long working hours. On the other hand, the urinary 8-OHdG level was negatively associated with high plasma LDL-cholesterol levels in non-smokers and anemia.

CONCLUSION

According to the results, anemia decreased the oxidative stress, regardless of smoking status, while leanness or high blood sugar increased the oxidative stress in smokers, and the presence of plasma cholesterol contributed to the lower oxidative stress in non-smokers. Certain types of occupational exposure may cause oxidative stress. The measurement of urinary 8-OHdG at annual health checks may be a useful biomarker for preventing lifestyle- and work-related diseases.

Induced sputum metabolomic profiles and oxidative stress are associated with chronic obstructive pulmonary disease (COPD) severity: potential use for predictive, preventive, and personalized medicine

Chronic obstructive pulmonary disease (COPD) is a highly heterogeneous disease, and metabolomics plays a hub role in predictive, preventive, and personalized medicine (PPPM) related to COPD. This study thus aimed to reveal the role of induced sputum metabolomics in predicting COPD severity. In this pilot study, a total of 20 COPD patients were included. The induced sputum metabolites were assayed using a liquid chromatography-mass spectrometry (LC-MS/MS) system. Five oxidative stress products (myeloperoxidase (MPO), superoxide dismutase (SOD), glutathione (GSH), neutrophil elastase (NE), and 8-iso-PGF2α) in induced sputum were measured by ELISA, and the metabolomic profiles were distinguished by principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA). The Kyoto Encyclopedia of Genes and Genomes (KEGG) was used for pathway enrichment analysis, and a significant difference in induced sputum metabolomics was observed between moderate and severe COPD. The KEGG analysis revealed that the glycerophospholipid metabolism pathway was downregulated in severe COPD. Due to the critical role of glycerophospholipid metabolism in oxidative stress, significant negative correlations were discovered between glycerophospholipid metabolites and three oxidative stress products (SOD, MPO, and 8-iso-PGF2α). The diagnostic values of SOD, MPO, and 8-iso-PGF2α in induced sputum were found to exhibit high sensitivities and specificities in the prediction of COPD severity. Collectively, this study provides the first identification of the association between induced sputum metabolomic profiles and COPD severity, indicating the potential value of metabolomics in PPPM for COPD management. The study also reveals the correlation between glycerophospholipid metabolites and oxidative stress products and their value for predicting COPD severity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-020-00227-w.

Toxicological Study and Genetic Basis of BTEX Susceptibility in Drosophila melanogaster

Benzene, toluene, ethylbenzene and xylene, also known as BTEX, are released into environmental media by petroleum product exploratory and exploitative activities and are harmful to humans and animals. Testing the effects of these chemicals on a significantly large scale requires an inexpensive, rapidly developing model organism such as Drosophila melanogaster. In this study, the toxicological profile of benzene, toluene, ethylbenzene, p-xylene, m-xylene, and o-xylene in D. melanogaster was evaluated. Adult animals were monitored for acute toxicity effects. Similarly, first instar larvae reared separately on the same compounds were monitored for the ability to develop into adult flies (eclosion). Further, the impact of fixed concentrations of benzene and xylene on apoptosis and mitosis were investigated in adult progenitor tissues found in third instar larvae. Toluene is the most toxic to adult flies with an LC₅₀ of 0.166 mM, while a significant and dose-dependent decrease in fly eclosion was observed with benzene, p-xylene, and o-xylene. An increase in apoptosis and mitosis was also observed in animals exposed to benzene and p-xylene. Through Genome Wide Association Screening (GWAS), 38 regions of the D. melanogaster genome were identified as critical for responses to p-xylene. This study reveals the strength of D. Melanogaster genetics as an accessible approach to study BTEX compounds.

Chrysin ameliorates aluminum phosphide-induced oxidative stress and mitochondrial damages in rat cardiomyocytes and isolated mitochondria

Apart from the anticancer, antioxidant, anti-inflammatory effects, and inhibition of aromatase, chrysin is involved in the protection of cardiovascular disorders. Cardiovascular complications are the main cause of death induced by aluminum phosphide (AlP) which is related to oxidative stress and mitochondrial damages. For this purpose, we investigated the effect of chrysin as an antioxidant and mitochondrial protective agent against AlP-induced toxicity in isolated cardiomyocytes and mitochondria obtained from rat heart ventricular. Using by biochemical and flow cytometry, cell viability, reactive oxygen species (ROS) formation, mitochondria membrane potential (MMP), lysosomal membrane integrity, malondialdehyde (MDA) content, and glutathione (GSH) and oxidized glutathione (GSSG) content were measured in isolated cardiomyocytes. Also, mitochondrial toxicity parameters such as mitochondrial NADH/succinate dehydrogenase activity, mitochondrial swelling, ROS formation, MMP collapse, and lipid peroxidation were analyzed in isolated mitochondria. Our results showed that the administration of chrysin (up to 10 μM) efficiently decreased (P < 0.05) cytotoxicity, oxidative, lysosomal, and mitochondrial damages induced by AlP, in isolated cardiomyocytes. Also, our finding in isolated mitochondria showed that chrysin (up to 10 μM) significantly (P < 0.05) decreased AlP-induced mitochondrial toxicity. These findings demonstrated that chrysin as an antioxidant and mitochondrial protective agent exert protective effect in wild-type cardiomyocyte treated with AlP. It was concluded that chrysin significantly reduced the toxicity of AlP in isolated cardiomyocytes and mitochondria. Due to the very low toxicity of chrysin for humans, it could be a promising agent in treatment of AlP poisoning.

Effects of quercetin loaded nanostructured lipid carriers on the paraquat-induced toxicity in human lymphocytes

Paraquat (PQ) as a herbicide and an environmental pollutant with increasing importance due to its toxicity to humans and animals. This study aimed to evaluate the protective and antioxidant activity of quercetin loaded Nanostructured Lipid Carriers (QNLC) against toxicity induced by PQ. Blood lymphocytes were prepared using Ficoll polysaccharide and subsequently by gradient centrifugation. The QNLC was prepared using an ultra-sonication method, which was characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The viability, reactive oxygen species (ROS), lipid peroxidation (LPO), mitochondrial membrane potential (MMP), lysosome membrane integrity, Bax and Bcl2 gene expression were evaluated in human isolated lymphocytes. The results showed spherical QNLCs with nano-size range (52.7 nm) and high drug encapsulation efficiency (98.5% -96%). The results also indicated that PQ induced cell death, as well as ROS production, decreased by QNLC in human lymphocytes. Also, QNLC meaningfully restored MMP reduction, lysosomal membrane destabilization, and lipid peroxidation and were capable of preventing PQ-treated change in Bax and Bcl2 gene expression. We report that QNLC, have a significantly higher capacity to prevent PQ-induced toxicity than Q itself. It is suggested that the QNLC is a promising antioxidant for drug delivery to be used as a therapeutic and prophylactic agent for PQ poisoning.

Effect of tartrazine on digestive enzymatic activities: in vivo and in vitro studies

Tartrazine (E102) is a synthetic food coloring, which belongs to the class of mono azo dyes and is known to cause numerous health problems. The current research aimed to evaluate the effect of this food dye on the enzymatic activity of amylase, lipase and proteases after a subchronic ingestion in Swiss mice. Additionally, an in vitro digestion model was used to highlight the relationship between the probable toxicity of tartrazine and the nature of the food ingested. The results show that there were no adverse effects of tartrazine on the body weight gain, and on amylase or lipase activities. However, in the high dose of tartrazine (0.05%) group, a significant decrease in trypsin and chymotrypsin enzymatic activities were observed. Regarding the in vitro digestion model, our findings show that there were no changes in the trypsin and chymotrypsin enzymatic activities either using 7.5 or 75 mg of tartrazine mixed with rice, butter or milk. We conclude that excessive consumption of tartrazine appears to alter the enzymatic activity of proteases in vivo which may have deleterious consequences on digestion. Even thought the dose close to the acceptable daily intake does not affect those activities, a strict control of tartrazine dose in high-consumption foods especially among children is an indispensable task.

Supply of Methionine During Late-Pregnancy Alters Fecal Microbiota and Metabolome in Neonatal Dairy Calves Without Changes in Daily Feed Intake

To our knowledge, most studies demonstrating the role of manipulating maternal nutrition on hindgut (i.e., large intestine) microbiota in the offspring have been performed in non-ruminants. Whether this phenomenon exists in cattle is largely unknown. Therefore, the objectives of the current study were to evaluate the impact of maternal post-ruminal supply of methionine during late-pregnancy in dairy cows on fecal microbiota and metabolome in neonatal calves, and their association with body development and growth performance during the preweaning period. To achieve this, heifer calves, i.e., neonatal female offspring, born to Holstein cows receiving either a control (CON) diet (n = 13) or CON plus rumen-protected methionine (MET; Evonik Nutrition & Care GmbH) during the last 28 days of pregnancy were used. Fecal samples from heifers were collected from birth until 6 weeks of age, i.e., the preweaning period. Fecal microbiota was analyzed with QIIME 2 whereas fecal metabolites were measured using an untargeted LC-MS approach. At birth, MET heifers had greater (P ≤ 0.05) BW, HH, and WH. During the preweaning period, no differences between groups were detected for starter intake (P = 0.77). However, MET heifers maintained greater (P ≤ 0.05) BW, HH and tended (P = 0.06) to have greater WH and average daily gain (ADG) (P = 0.10). Fecal microbiota and metabolome profiles through 42 days of age in MET heifers indicated greater capacity for hindgut production of endogenous antibiotics and enhanced hindgut functionality and health. Enhancing maternal post-ruminal supply of methionine during late-gestation in dairy cows has a positive effect on hindgut functionality and health in their offspring through alterations in the fecal microbiota and metabolome without affecting feed intake. Those alterations could limit pathogen colonization of the hindgut while providing essential nutrients to the neonate. Together, such responses contribute to the ability of young calves to achieve better rates of nutrient utilization for growth.

Human steroid sulfatase enhances aerobic glycolysis through induction of HIF1α and glycolytic enzymes

Human steroid sulfatase (STS) has been linked with poor prognosis in steroid-associated tumors and represents an important clinical target in cancers, yet the mechanism of STS-induced carcinogenesis remains unclear. To correlate STS with cancer metabolism, we determined the effects of STS on aerobic glycolysis. STS overexpression increased cellular levels of lactic acid, the final product of aerobic glycolysis. Moreover, STS suppressed the oxygen consumption rate (OCR), which represents mitochondrial respiration. Inhibition of STS by the specific inhibitor STX064 recovered STS-induced OCR repression and lactic acid over-production. DHEA, but not DHEA-S, suppressed the OCR level and enhanced lactic acid production. To understand the molecular mechanism of STS-induced cancer metabolism, we measured the expression of glycolytic enzymes hexokinase 2 (HK2) and pyruvate kinase M2 (PKM2), which was highly upregulated by STS and DHEA at both protein and mRNA levels. HIF1α is a key mediator of aerobic glycolysis, and STS enhanced HIF1α promoter activity, mRNA expression, and protein expression. Down-regulation of HIF1α by siRNA suppressed the HK2 and PKM2 expression induced by both STS and DHEA. HIF1α siRNA also recovered the OCR repression and lactic acid over-production induced by both STS and DHEA. To explore the mechanism in vivo, we produced transgenic mice overexpressing STS and found that STS expression was particularly enhanced in the lung. Consistent with our in vitro results, the expression of HIF1α, HK2, and PKM2 was also increased in mouse lung tissues. In conclusion, we suggest that STS may induce aerobic glycolysis through enhancing HIF1α expression.

Wood dust and urinary 15-F2t isoprostane in Italian industry workers

Wood dust is one of the most common occupational exposures, with about 3.6 million of workers in the wood industry in Europe. Wood particles can deposit in the nose and the respiratory tract and cause adverse health effects. Occupational exposure to wood dust has been associated with malignant tumors of the nasal cavity and paranasal sinuses. The induction of oxidative stress and the generation of reactive oxygen species through activation of inflammatory cells could have a role in the carcinogenicity of respirable wood dust. Therefore, we conducted a cross-sectional study to evaluate the prevalence of urinary 15-F_2t isoprostane (15-F_2t-IsoP), a biomarker of oxidative stress and peroxidation of lipids, in 123 wood workers compared to 57 unexposed controls living in Tuscany region, Italy. 15-F_2t-IsoP generation was measured by ELISA. The main result of the present study showed that a statistically significant excess of this biomarker occurred in the workers exposed to 1.48 mg/m³ of airborne wood dust with respect to the unexposed controls. The overall mean ratio (MR) between the workers exposed to wood dust and the controls was 1.36, 95% Confidence Interval (C.I.) 1.18-1.57, after correction for age and smoking habits. A significant increment of 15-F_2t-IsoP (43%) was observed in the smokers as compared to the non-smokers. The urinary excretion of 15-F_2t-IsoP was significantly associated with co-exposure to organic solvents, i.e., MR of 1.41, 95% C.I. 1.17-1.70, after adjustment for age and smoking habits. A 41% excess was observed in long-term wood workers, 95% C.I. 1.14-1.75. Multivariate regression analysis showed that the level of 15-F_2t-IsoP was linearly correlated to the length of exposure, regression coefficient (β) = 0.244 ± 0.002 (SE). The overall increment by exposure group persisted after stratification for smoking habits. For instance, in smokers, a 53% excess was detected in the wood workers as compared to the controls, 95% C.I. 1.23-1.91. Our data support the hypothesis that oxidative stress and lipid peroxidation can have a role in the toxicity of wood dust F₂-IsoP measure can be a tool for the evaluation of the effectiveness of targeted interventions aimed to reduce exposures to environmental carcinogens.

Embryotoxic and Teratogenic Effects of Tartrazine in Rats

Tartrazine (TAZ) is one of the most commonly used artificial dyes for foods and drugs. We determined the effect of TAZ on fetal development by examining morphological, visceral, and skeletal malformations in rat fetuses following daily oral administration of TAZ to pregnant Wistar rats at the 6th-15th day of gestation. TAZ at 0.45 and 4.5 mg/kg induced 6.0 and 7.1% fetal resorptions, as well as 10.0 and 10.5% fetal mortality, respectively. Fetal body weight and length were significantly lower in the groups treated with TAZ at 0.45 (3.97 ± 0.21 g and 27.3 ± 0.54 mm, respectively) and 4.5 mg/kg (3.48 ± 0.15 g and 23.22 ± 1.02 mm, respectively) than in the control group (4.0 ± 0.15 g and 30.01 ± 0.42 mm, respectively). TAZ at 0.45 and 4.5 mg/kg induced hepatic damage (20 and 33.3%, respectively), dark brown pigmentation due to hemosiderin in the splenic parenchyma (16.7 and 21.7%, respectively), as well as destructed and necrotic renal tubules (16.7 and 26.7%, respectively) in the fetuses. Moreover, TAZ at 0.45 and 4.5 mg/kg caused one or more missing coccygeal vertebrae (20 and 40%, respectively), missing sternebrae (6 and 10%, respectively), missing hind limbs (24 and 4%, respectively), and irregular ribs (16 and 20, respectively) in the fetuses. We concluded that TAZ has embryotoxic and teratogenic potentials in rats.

Shikonin Exerts Cytotoxic Effects in Human Colon Cancers by Inducing Apoptotic Cell Death via the Endoplasmic Reticulum and Mitochondria-Mediated Pathways

The apoptotic effects of shikonin (5,8-dihydroxy-2-[(1R)-1-hydroxy-4-methylpent-3-enyl]naphthalene-1,4-dione) on the human colon cancer cell line SNU-407 were investigated in this study. Shikonin showed dose-dependent cytotoxic activity against SNU-407 cells, with an estimated IC₅₀ value of 3 µM after 48 h of treatment. Shikonin induced apoptosis, as evidenced by apoptotic body formation, sub-G₁ phase cells, and DNA fragmentation. Shikonin induced apoptotic cell death by activating mitogen-activated protein kinase family members, and the apoptotic process was mediated by the activation of endoplasmic reticulum (ER) stress, leading to activation of the PERK/elF2α/CHOP apoptotic pathway, and mitochondrial Ca²⁺ accumulation. Shikonin increased mitochondrial membrane depolarization and altered the levels of apoptosis-related proteins, with a decrease in B cell lymphoma (Bcl)-2 and an increase in Bcl-2-associated X protein, and subsequently, increased expression of cleaved forms of caspase-9 and -3. Taken together, we suggest that these mechanisms, including MAPK signaling and the ER-and mitochondria-mediated pathways, may underlie shikonin-induced apoptosis related to its anticancer effect.

Total Synthesis and Biological Evaluation of Sericetin for Protection against Cisplatin-Induced Acute Kidney Injury

A concise synthesis of sericetin (1) was performed in four steps from readily available 3- O-benzylgalangin (4), featuring electrocyclization to produce the tricyclic core and a sequential aromatic Claisen/Cope rearrangement to incorporate the 8-prenyl group of 1. In addition, the therapeutic potential of sericetin (1), isosericetin (2), and three prenylated tetracyclic synthetic intermediates (11, 12, and 14) against cisplatin-induced nephrotoxicity using renal tubular cells were evaluated. Compound 14 showed therapeutic potential against cisplatin-induced kidney damage.

Schisandrin A prevents oxidative stress-induced DNA damage and apoptosis by attenuating ROS generation in C2C12 cells

The generation of excessive reactive oxygen species (ROS) by oxidative stress has various deleterious effects on cellular constituents. Therefore, the discovery of natural products that can inhibit the production of ROS may be effective in suppressing the onset and treatment of oxidative stress-mediated diseases. Despite the antioxidant efficacy studies on various substances in the genus Schisandra used as traditional medicine, research on the efficacy of schisandrin A, a class of active lignans, remains insufficient. This study was conducted to evaluate the protective effect of schisandrin A on DNA damage and apoptosis induced by hydrogen peroxide (H₂O₂) in C2C12 cells. Results showed that schisandrin A effectively attenuated H₂O₂-induced cytotoxicity and DNA damage, which was related to the blockage of ROS accumulation. Schisandrin A also prevented the decrease in ATP content by H₂O₂ and restored the H₂O₂-induced activation of AMP-activated protein kinase. In addition, schisandrin A prevented the release of H₂O₂-induced cytochrome c into the cytoplasm presumably by inhibiting the loss of mitochondrial membrane potential and the changes in the Bcl-2 family protein expression by H₂O₂. Furthermore, the blocking of H₂O₂-induced apoptosis by schisandrin A was associated with the inhibition of poly (ADP-ribose) polymerase degradation by the inactivation of caspase-3. These results suggest that schisandrin A maintains energy metabolism through the preservation of mitochondrial function while eliminating ROS generated by H₂O₂ in C2C12 cells. Therefore, our data indicate that schisandrin A may have a beneficial effect on the prevention and treatment of diseases associated with apoptosis induced by oxidative stress.

Sargassum serratifolium attenuates RANKL-induced osteoclast differentiation and oxidative stress through inhibition of NF-κB and activation of the Nrf2/HO-1 signaling pathway

Sargassum serratifolium C. Agardh is a marine brown alga that has long been used as an ingredient for food and medicine by many people living along Asian coastlines. Recently, various beneficial effects of extracts or compounds isolated from S. serratifolium have been reported, but their efficacies against bone destruction are unclear. Therefore, in this study, we investigated the inhibitory property of an ethanol extract of S. serratifolium (EESS) on osteoclast differentiation by focusing on the receptor activator of nuclear factor-κB ligand (RANKL)-stimulated osteoclastogenesis model using RAW 264.7 macrophages. Our results demonstrated that EESS reduced RANKL-induced osteoclast differentiation in RAW 264.7 cells, by inhibiting tartrate-resistant acid phosphatase (TRAP) activity and destroying the F-actin ring formation. EESS also attenuated RANKL-induced expressions of key osteoclast-specific genes, such as nuclear factor of activated T cells cytoplasmic 1 (NFATC1), TRAP, cathepsin K and matrix metalloproteinase-9. These effects were mediated by impaired nuclear translocation of nuclear factor (NF)-κB and suppression of IκB-α degradation. In addition, EESS effectively inhibited the production of reactive oxygen species (ROS) by RANKL, which was associated with enhanced expression of nuclear translocation of nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). Overall, our findings provide evidence that EESS suppresses RANKL-induced osteoclastogenesis and oxidative stress through suppression of NF-κB and activation of Nrf2/HO-1 signaling pathway, indicating that S. serratifolium has a potential application the prevention and treatment of osteoclastogenic bone disease.