Endogenous Oxidative Stress Research Articles

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

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

Structural Characterization of Neisseria gonorrhoeae Bacterial Peroxidase-Insights into the Catalytic Cycle of Bacterial Peroxidases.

Neisseria gonorrhoeae is an obligate human pathogenic bacterium responsible for gonorrhea, a sexually transmitted disease. The bacterial peroxidase, an enzyme present in the periplasm of this bacterium, detoxifies the cells against hydrogen peroxide and constitutes one of the primary defenses against exogenous and endogenous oxidative stress in this organism. The 38 kDa heterologously produced bacterial peroxidase was crystallized in the mixed-valence state, the active state, at pH 6.0, and the crystals were soaked with azide, producing the first azide-inhibited structure of this family of enzymes. The enzyme binds exogenous ligands such as cyanide and azide, which also inhibit the catalytic activity by coordinating the P heme iron, the active site, and competing with its substrate, hydrogen peroxide. The inhibition constants were estimated to be 0.4 ± 0.1 µM and 41 ± 5 mM for cyanide and azide, respectively. Imidazole also binds and inhibits the enzyme in a more complex mechanism by binding to P and E hemes, which changes the reduction potential of the latest heme. Based on the structures now reported, the catalytic cycle of bacterial peroxidases is revisited. The inhibition studies and the crystal structure of the inhibited enzyme comprise the first platform to search and develop inhibitors that target this enzyme as a possible new strategy against N. gonorrhoeae.

Large-Scale Qualitative and Quantitative Assessment of Dityrosine Crosslinking Omics in Response to Endogenous and Exogenous Hydrogen Peroxide in Escherichia coli.

Excessive hydrogen peroxide causes oxidative stress in cells. The oxidation of two tyrosine residues in proteins can generate o,o'-dityrosine, a putative biomarker for protein oxidation, which plays critical roles in a variety of organisms. Thus far, few studies have investigated dityrosine crosslinking under endogenous or exogenous oxidative conditions at the proteome level, and its physiological function remains largely unknown. In this study, to investigate qualitative and quantitative dityrosine crosslinking, two mutant Escherichia coli strains and one mutant strain supplemented with H2O2 were used as models for endogenous and exogenous oxidative stress, respectively. By integrating high-resolution liquid chromatography-mass spectrometry and bioinformatic analysis, we created the largest dityrosine crosslinking dataset in E. coli to date, identifying 71 dityrosine crosslinks and 410 dityrosine loop links on 352 proteins. The dityrosine-linked proteins are mainly involved in taurine and hypotaurine metabolism, citrate cycle, glyoxylate, dicarboxylate metabolism, carbon metabolism, etc., suggesting that dityrosine crosslinking may play a critical role in regulating the metabolic pathways in response to oxidative stress. In conclusion, we have reported the most comprehensive dityrosine crosslinking in E. coli for the first time, which is of great significance in revealing its function in oxidative stress.

Biochemical Origin of the Warburg Effect in Light of 15 Years of Research Experience: A Novel Evidence-Based View (An Expert Opinion Article).

Cancer cells strongly upregulate glucose uptake and glycolysis to produce vital biomolecules for cancer cell survival, proliferation, and metastasis as ATP, lipids, proteins, nucleotides, and lactate. The Warburg effect is tumours' unique glucose oxidation to give lactate (not pyruvate) even in the presence of oxygen. Nicotinamide adenine dinucleotide (NAD/NADH.H) is used in glycolysis via glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and lactate dehydrogenase (LDH). Both catalyse reversible biochemical reactions to produce 1,3-diphosphoglycerate and lactate, respectively. In this expert opinion and based on published evidence, the author suggests that: "In transformed cells and hyperglycolytic cancer cells, the Warburg effect (permanent conversion of pyruvate to lactate) occurs secondary to a vicious cycle and a closed circuit between GAPDH and LDH (reaction of carcinogenesis) causing increased endogenous oxidative stress and subsequent carcinogenesis. Mitochondrial defects in cancer cells cause hyperglycolysis resulting in NADH.H accumulation (produced during GAPDH step) that obligatorily drives LDH to become an irreversible reaction in the direction of lactate formation (Warburg effect) but not pyruvate formation. Likewise, LDH oxidizes NADH.H producing excessive NAD+ that secondarily drives GAPDH reaction to be irreversible to produce NADH.H and so on. Pyruvate is an antioxidant while lactate is pro-oxidant, causing increased endogenous oxidative stress in cancer cells, tumour's hypoxia and obligatory hyperglycolysis with NADH.H overproduction (GAPDH step) to be consumed in the LDH step for lactate production and NAD+ generation (utilized by GAPDH) and so on". This confirms Warburg's origin of cancer cells. Best anticancer applications based on this hypothesis are: breaking this closed vicious circle using siRNA to target GAPDH and LDH, avoiding strong oxidants (as many cancer chemotherapeutics), and using strong antioxidants for causing antioxidant-oxidant antagonism or antioxidant-lactate antagonism to inhibit the Warburg effect. Strong natural antioxidants of prophetic medicine (related to Prophet Muhammad peace be upon him) such as Zamzam water, Nigella sativa, costus, Ajwa date fruit, olive oil, Al-hijamah and natural honey are strongly recommended to prevent and antagonize the Warburg effect.

Endogenous intoxication, oxidative stress and antioxidant system in acute lower limb ischemia

Aim. To study features of endogenous intoxication syndrome (EI), oxidative stress (LPO) and antioxidant defence (AOS) in patients with acute lower limb ischemia (LLI).Materials and methods. Some parameters of EI, LPO and AOS were studied. EI syndrome was studied in 86 patients with LLI who underwent complex examination and treatment in 2020-2021 in the Department of Vascular Surgery of the RNCfCS. POL and AOS parameters were studied in 14 patients out of 86. There were 51 (59.3%) men and 35 (40.7%) women, mean age was 56.0±5.8 years. Acute occlusion of the iliofemoral segments was noted in 33 (38.4%) patients, in 32 (37.2%) - the femoral segment, and in 21 (24.4%) - the popliteal and femoral vessels. In all cases, ischemia had a unilateral localization - on the right in 59 (68.6%) cases and on the left in 27 (31.4%) cases. In 52 (58.1%) cases, there were clinical signs of grade II b ischemia, and in 36 (41.9%) cases - grade III A (according to V.S. Saveliev, 1987). The average duration of ischemia was 77.9±28.3 hours.Results and discussion. In all cases of LLI before revascularization, there were signs of acute inflammatory reaction and EI syndrome in the form of increased ESR (42.3±7.1 mm/h), CRP concentration (16.1±4.2 mg/L), fibrinogen (8.5±0.9 g/L) and leukocytosis (12.7±1.5×109/L). Also, all patients had a slight elevation of blood glucose against the background of EI (7.5±1.8 mmol/L), a significant increase of creatinine concentration (128.9±6.1 µmol/L), urea (9.2±0.6 mmol/L) and aminotransferases as compared to normal indices. Results of LPO and AOS indices study in 14 patients showed that in LLI, malondialdehyde (MDA) increases 2.6-fold (3.9±0.1 μmol/L), diene conjugate increases 3.7-fold (0.77±0.04 units a/mL). However, after the elimination of ischemia, there was no significant decrease for 12.2±2.4 days, which confirms the presence of reperfusion syndrome. AOS indices - superoxide dismutase (20,8±1,0 u/l) and catalase (128,9±11,2 μl/l) increased 1,2 and 1,1 times in the examined patients cohort, respectively. Statistically significant associations were established between the following indices: Ischemia level and urea (r=0.89), Ischemia level and white blood cell count (r=-0.82), Hb and Er (r=0.99), Hb and creatinine (r=0.79), Hb and urea (r=0.79), Er and urea (r=0.79), creatinine and Er (r=0.90), ACTV and creatinine (r=-0.77), creatinine and urea (r=0.90).Conclusion. Acute lower limb ischemia is accompanied by ischemia-reperfusion damage manifested by endogenous intoxication syndrome, impaired glucose metabolism and activation of lipoperoxidation processes and antioxidant system. After the elimination of acute ischemia, there is not always a significant decrease in lipid peroxidation and some inflammation parameters. Therefore, prolonged use of antioxidants in the reperfusion period is recommended.

SOD2 in platelets: with age comes responsibility

SOD2 in platelets: with age comes responsibility

Wamena Arabica Coffee (Coffea Arabica) Bean Extract Cream Inhibits The Increase Of Tyrosynase And Melanin Levels In Guinea Pig (Cavia Porcellus) Exposed To UVB Lights

Introduction: Most of the aging process in the skin occurs due to exposure to sunlight, especially UV-B light, resulting in an increase in the activity of the tyrosinase enzyme and the amount of melanin which will cause hyperpigmentation of the skin. Antioxidants are substances that can provide protection from endogenous and exogenous oxidative stress by free radicals. The purpose of this study was to prove that Wamena roasted Arabica coffee bean extract cream can inhibit the enzymes tyrosinase and melanin in guinea pig exposed to UV-B lights. Methods: The design of this study was an animal experimental design with a randomized post-test only control group. The subjects of the study were 30 guinea pigs divided into 3 groups: group 1 as control, group 2 with placebo cream and group 3 was with 3% Wamena arabica coffee bean extract cream. The group 2 and 3 were exposed to UV-B light for 2 weeks. The skin of the guinea pig was excised for examination of the levels of the enzymes tyrosinase and melanin. Result: The average tyrosinase and melanin levels in control group were 19.891% and 4.62%, treatment group 2 was an average of 42.699% and 9.26% and treatment group 3 was 23.886% and 4.87%. Conclusion: Arabica coffee (Coffea arabica) bean extract cream roasted Wamena 3% inhibits the tyrosinase enzyme levels and inhibits the melanin in guinea pigs (Cavia porcellus) which are exposed to ultraviolet B light.

Antioxidants: Structure-activity of plant polyphenolics.

The excessive accumulation of reactive oxygen species (ROS)/free radicals can lead to abnormal oxidation of biomolecules such as proteins, lipids, fats, carbohydrates and nucleic acids in human organisms. Accordingly, endogenous oxidative stress induces the progressive development of various chronic diseases like rheumatoid arthritis, cancers, cardiovascular risks, diabetes, digestive ulcers, hypertension, obesity, neurological disorders, and age-related complications. Therefore, anti-oxidant defense mechanisms are needed to control/prevent the unbalanced molecular oxidative damage. Indeed, the oxidative stress arises from both endogenous and exogenous factors such as smoking, alcohol, medications, air pollution, sunlight, lifestyle disorders, and metabolic processes. Therefore, consumption of fruits, vegetables, grains, beverages, and leafy vegetables rich in antioxidants may inhibit or treat oxidative damage accompanying diseases. From this aspect, dietary foods are rich in various antioxidant metabolites such as flavonoids, vitamin A, C, E, phenolic acids, curcumin, stilbenes, anthocyanins, etc., which promote healthy life and nutritional benefits. Additionally, various studies have also proven that foods rich in antioxidants interact with reactive species to prevent cell damage(s) or therapeutic pathways for diseases. Although, there are various myths about the antioxidant mechanism(s), the optimal dosage of antioxidants can show beneficial pharmacological activities against various molecular oxidation paths.

Neuroprotection in Aβ25-35 -Induced Alzheimer's Disease Model by Hawthorn Leaf Flavonoids

It has been observed that increased accumulation of Aβ peptides in the brain triggers endogenous oxidative stress, neuroinflammation, and memory dysfunction in Alzheimer’s Disease (AD). Crataegus pinnatifida Bge. Commonly referred to as the Hawthorn leaf is a well-known traditional Chinese medicine. The plant is used for conditions such as hyperlipidemia, heart palpitations, forgetfulness, and tinnitus in mainstream medicinal practice, where the most important bioactive components consist of Hawthorn Leaf Flavonoids (HLF). Xu and associates showed that in a rat model given Aβ25-35 (bilateral hippocampus injection), the neuroprotective effects of HLF were significant. Oral doses of 50, 100, and 200 mg/kg for a time period of 30 days of HLF demonstrated significant attenuation of the damage to neurons alongside marked inhibition in memory deficits. Enhancement in the enzyme activities of superoxide dismutase and catalase, and glutathione content was seen. In contrast, HLF decreased the malondialdehyde content in the Aβ25-35 rat AD model and suppressed astrocytes’ activation, ameliorating neuroinflammation. HLF upregulated NQO-1, Nrf-2, and HO-1 protein expressions. These results demonstrated the potential of HLF as a potential AD therapeutic. Phytother Res (2022) DOI: 10.1002/ptr.7690.

Fluorinated triphenylphosphonium analogs improve cell selectivity and invivo detection of mito-metformin.

Triphenylphosphonium (TPP+) conjugated compounds selectively target cancercells by exploiting their hyperpolarized mitochondrial membrane potential. Todate, studies have focused on modifying either the linker or the cargo of TPP+-conjugated compounds. Here, we investigated the biological effects ofdirect modification to TPP+ to improve the efficacy and detection of mito-metformin (MMe), a TPP+-conjugated probe we have shown to have promising preclinical efficacy against solid cancer cells. We designed, synthesized, and tested trifluoromethyl and methoxy MMe analogs (pCF3-MMe, mCF3-MMe, and pMeO-MMe) against multiple distinct human cancer cells. pCF3-MMe showed enhanced selectivity toward cancer cells compared to MMe, while retaining thesame signaling mechanism. Importantly, pCF3-MMe allowed quantitative monitoring of cellular accumulation via 19F-NMR invitro and invivo. Furthermore, adding trifluoromethyl groups to TPP+ reduced toxicity invivo while retaining anti-tumor efficacy, opening an avenue to de-risk these next-generation TPP+-conjugated compounds.

Isozyme-specific histone deacetylase 1/2 inhibitor K560 attenuates oxidative stress-induced retinal cell death

Oxidative stress-induced damage is an underlying mechanism in the pathogenesis of age-related retinal diseases. Here, we examined the effects of K560, a potential candidate drug for the treatment of these diseases, on oxidative stress-induced retinal cell death. K560 is a novel isozyme-specific inhibitor of histone deacetylase 1 and 2 (HDAC1/2). Histone acetylation in retinal lysates and dissociated retinal cells was detected with a western blot analysis and cell-based enzyme-linked immunosorbent assay (ELISA), respectively. The viability of mouse retinal cells was measured with an alamarBlue assay. We used immunohistochemistry for RNA binding protein with multiple splicing (RBPMS) to visualize the retinal ganglion cells (RGCs) of mice. An ELISA analysis indicated that histone acetylation was enhanced in dissociated mouse retinal cells treated with K560. The cell viability assay indicated that K560 attenuated both exogenous hydrogen peroxide–induced and endogenous oxidative stress–induced cell death in dissociated retinal cells. Western blot analysis indicated that intravitreal K560 administration enhanced the acetylation of histones H3 and H4 in mouse retinal lysates. To examine the effect of K560 on oxidative stress–induced RGC death, we performed whole-mount immunohistochemistry for RBPMS on retinas dissected from eyes treated with K560 or vehicle on day one, and K560 or vehicle and NMDA on day two. Quantification of RBPMS-immunopositive cells indicated that K560 attenuated NMDA-induced RGC death. Taken together, our findings suggest that administration of a HDAC1/2-specific inhibitor K560 may be effective in the treatment of oxidative stress–mediated retinal degeneration and have less cytotoxicity than other known HDAC inhibitors, which are known to target a wide range of HDAC family members.

Mechanisms of P-Glycoprotein Regulation Under Exogenous and Endogenous Oxidative Stress In Vitro.

We investigated the mechanisms of P-glycoprotein (P-gp) transporter regulation in Caco-2 cells under exogenous and endogenous oxidative stress (OS). Exogenous OS was modeled by exposure of the growth medium to hydrogen peroxide at concentrations of 0.1, 0.5, and 1 μM for 24 h or 10 μM for 72 h. Endogenous OS was modeled by incubating cells with DL-buthionine sulfoximine (BSO, gamma-glutamylcysteine synthetase inhibitor) at a concentration of 10, 50, and 100 μM for 24 h. The levels of intracellular reactive oxygen species (ROS) were assessed using MitoTracker Red CM-H2XRos fluorescent probes. Relative P-gp contents were analyzed using Western blot. Exogenous and endogenous OS was shown to increase relative to P-gp contents. An important role played by the Nrf2-Keap1 signaling pathway in increasing the P-gp contents under H2O2-induced exogenous OS was revealed using specific inhibitors. The transcription factor HIF1 is involved in the regulation of the P-gp levels under 24-hour exogenous OS, and the transcription factor CAR is involved in the regulation of transporter levels under 72-hour OS. All tested transcription factors and signaling pathways are involved in P-gp induction under endogenous OS. Most likely, this is associated with the bimodal effect of BSO on Pgp. On the one hand, BSO induces the development of OS; on the other, BSO, as a xenobiotic, is able to stimulate PXR and CAR, which, in turn, increase the P-gp contents.

A Cross-Sectional Measurement of Endogenous Oxidative Stress Marker Levels in Obsessive Compulsive Disorder.

There is a correlation between the increase in reactive oxygen radicals and the presence of specific mental illnesses. In this context, the objective of this study is to investigate the relationship between obsessive-compulsive disorder and the variations in the levels of several endogenous oxidative stress markers. Thirty obsessive-compulsive disorder patients were included in the study as the patient group, and 30 healthy volunteers of matching demographic characteristics were included in the study as the control group. Accordingly, the patient group consisted of 10 females and 20 males with a mean age of 29.5 ± 6.1 years, and the control group consisted of 15 females and 15 males with a mean age of 31.9±5.6 years. The serum nicotinamide adenine dinucleotide phosphate oxidase-2, nicotinamide adenine dinucleotide phosphate oxidase-4, and malondialdehyde levels of the 2 groups were compared using the independent samples t-test. The relationships between the serum nicotinamide adenine dinucleotide phosphate oxidase-2, nicotinamide adenine dinucleotide phosphate oxidase-4, and malondialdehyde levels of the 2 groups were analyzed using the Pearson's correlation coefficient. The serum nicotinamide adenine dinucleotide phosphate oxidase-2, nicotinamide adenine dinucleotide phosphate oxidase-4, and malondialdehyde levels of the patient group were statistically significantly higher than those of the control group (P < .001). Statistically significant positive correlations were detected between the serum nicotinamide adenine dinucleotide phosphate oxidase-2 and nicotinamide adenine dinucleotide phosphate oxidase-4 levels (r = 0.692, P = .001) and between the serum nicotinamide adenine dinucleotide phosphate oxidase-2 and malondialdehyde levels (r = 0.563, P = .001). The results of this study indicated that oxidative stress and lipid peroxidation levels were higher in obsessive-compulsive disorder patients. Based on this finding, NOX-2 and NOX-4 levels can be used as indicators of endogenous oxidative stress in obsessive-compulsive disorder patients.

Insights into the antibacterial mechanism of ozone water combined with tea polyphenols against Shewanella putrefaciens: membrane disruption and oxidative stress

SummaryShewanella putrefaciens (S. putrefaciens) is the main specific spoilage organism (SSO) of marine fish during cold logistic process. To explore the antimicrobial mechanism of ozone water combined with tea polyphenol (TP) against S. putrefaciens, the growth condition, endogenous oxidative stress, changes of membrane integrity and energy metabolism enzyme were evaluated, respectively. As evidenced by the growth curve and confocal laser scanning microscopy (CLSM) analysis, bacterial growth was inhibited, and death threat occurred. The increase of reactive oxygen species (ROS) suggested intracellular oxidative stress was activated. Additionally, membrane integrity and metabolism functions were destroyed according to the results of alkaline phosphatase (AKPase), β‐galactosidase, transmembrane electrical potential, scanning electron microscope (SEM), adenosine triphosphatase (ATPase) and lactate dehydrogenase (LDHase). In summary, the inactivation of S. putrefaciens could be induced by the combination of ozone water and TP, which provided a theoretical basis for the sterilisation in aquatic products.

Using follicular fluid metabolomics to investigate the association between air pollution and oocyte quality

Background and aimOur objective was to use metabolomics in a toxicological-relevant target tissue to gain insight into the biological processes that may underlie the negative association between air pollution exposure and oocyte quality. MethodsOur study included 125 women undergoing in vitro fertilization at an academic fertility center in Massachusetts, US (2005–2015). A follicular fluid sample was collected during oocyte retrieval and untargeted metabolic profiling was conducted using liquid chromatography with ultra-high-resolution mass spectrometry and two chromatography columns (C18 and HILIC). Daily exposure to nitrogen dioxide (NO2), ozone, fine particulate matter, and black carbon was estimated at the women’s residence using spatiotemporal models and averaged over the period of ovarian stimulation (2-weeks). Multivariable linear regression models were used to evaluate the associations between the air pollutants, number of mature oocytes, and metabolic feature intensities. A meet-in-the-middle approach was used to identify overlapping features and metabolic pathways. ResultsOf the air pollutants, NO2 exposure had the largest number of overlapping metabolites (C18: 105; HILIC: 91) and biological pathways (C18: 3; HILIC: 6) with number of mature oocytes. Key pathways of overlap included vitamin D3 metabolism (both columns), bile acid biosynthesis (both columns), C21-steroid hormone metabolism (HILIC), androgen and estrogen metabolism (HILIC), vitamin A metabolism (HILIC), carnitine shuttle (HILIC), and prostaglandin formation (C18). Three overlapping metabolites were confirmed with level-1 or level-2 evidence. For example, hypoxanthine, a metabolite that protects against oxidant-induced cell injury, was positively associated with NO2 exposure and negatively associated with number of mature oocytes. Minimal overlap was observed between the other pollutants and the number of mature oocytes. ConclusionsHigher exposure to NO2 during ovarian stimulation was associated with many metabolites and biologic pathways involved in endogenous vitamin metabolism, hormone synthesis, and oxidative stress that may mediate the observed associations with lower oocyte quality.

Dietary intake of deuterium oxide decreases cochlear metabolism and oxidative stress levels in a mouse model of age-related hearing loss

Age-related hearing loss (ARHL) is the most prevalent sensory disorder in the elderly. Currently, no treatment can effectively prevent or reverse ARHL. Aging auditory organs are often accompanied by exacerbated oxidative stress and metabolic deterioration. Here, we report the effect of deuterated oxygen (D2O), also known as “heavy water”, mouse models of ARHL. Supplementing the normal mouse diet with 10% D2O from 4 to 9 weeks of age lowered hearing thresholds at selected frequencies in treated mice compared to untreated control group. Oxidative stress levels were significantly reduced and in the cochlear duct of treated vs. untreated mice. Through metabolic flux analysis, we found that D2O mainly slowed down catabolic reactions, and may delay metabolic deterioration related to aging to a certain extent. Experiments confirmed that the Nrf2/HO-1/glutathione axis was down-regulated in treated mice. Thus, D2O supplementation can hinder ARHL progression in mouse models by slowing the pace of metabolism and reducing endogenous oxidative stress production in the cochlea. These findings open new avenues for protecting the cochlea from oxidative stress and regulating metabolism to prevent ARHL.

Methanol leaf extract of Simarouba glauca induced dyslipidemia-linked cardiovascular disease indicators and its effect on antioxidant proteins

The study focused on the effect of methanol leaf extract of Simarouba glauca (MESG) on lipoproteins cholesterols and oxidative stress biomarkers in male Wistar rat. Toxicological inquest of MESG was evaluated as prescribed in the guidelines of organization for economic co-operation and development (OECD), No. 425. A total of twenty-four male Wistar rats were used; divided into four groups of six rats each, including the control. Test rats were given MESG 500, 1000 and 2000 mg/kg body weight respectively, daily for thirty (30) days. At the end of the study, the rats were fasted overnight and sacrificed and biochemical indicators were evaluated. Results showed marked increase (p ˂ 0.05) in Total Cholesterol at MESG 2000 mg/kg; a reduction and increase (p ˂ 0.05) in High-Density Lipoprotein Cholesterol and Triglycerides respectively, at all doses; an increase (p ˂ 0.05) in Low- Density Lipoprotein Cholesterol at MESG 2000 mg/kg. Additional data indicated no changes (p ˃ 0.05) in Malondialdehyde levels; liver Catalase was significantly (p ˂ 0.05) expressed at MESG 500 and 2000 mg/kg, kidney CAT was significantly (P ˂ 0.05) expressed at all doses. The liver Superoxide Dismutase (SOD) was significantly (p ˂ 0.05) expressed at MESG 1000 and 2000 mg/kg; the kidney and heart SOD were also significantly (P ˂ 0.05) expressed at MESG 500 and 2000 mg/kg respectively. The plasma GSH-PX was significantly (P ˂ 0.05) expressed at MESG 1000 mg/kg; while the liver and heart GSH-PX were significantly (P ˂ 0.05) expressed and repressed at 500 mg/kg respectively. Conclusively, MESG elicited obvious dyslipidemia; accompanied by marked alterations in selected endogenous oxidative stress biomarkers.

Haloperidol Prevents Oxytosis/Ferroptosis by Targeting Lysosomal Ferrous Ions in a Manner Independent of Dopamine D2 and Sigma-1 Receptors.

Haloperidol is a widely used antipsychotic agent that exerts antipsychotic effects through a strong antagonism of dopamine D2 receptors. In addition, haloperidol is classified as a sigma-1 receptor (S1R) antagonist that prevents endogenous oxidative stress in cultured cells. However, pharmacological activities of haloperidol against oxidative stress remain unclear. Oxytosis/ferroptosis are iron-dependent nonapoptotic oxidative cell deaths that are regarded as two names for the same cell death pathway and the potential physiological relevance of oxytosis/ferroptosis in multiple diseases is suggested. In the present study, the effects of haloperidol on oxytosis/ferroptosis were investigated in S1R-knockdown mouse hippocampal HT22 cells. The results indicate that haloperidol is a strong inhibitor of oxytosis/ferroptosis independent of S1R. Imaging of HT22 cells with a newly developed fluorescent probe showed that haloperidol was localized to late endosomes and lysosomes and reduced the accumulation of lysosomal ferrous ions, resulting in reduced production of intracellular reactive oxygen species and inhibition of cell death. These results indicate that haloperidol is useful not only as an antipsychotic agent but also as a neuroprotective agent against endogenous oxidative stress via distinct mechanisms. Furthermore, lysosome-targeting ferroptosis inhibitors could be useful for the treatment of various diseases, including cancers, ischemia-reperfusion injury, and neurodegenerative disorders, which have been associated with ferroptosis.

A method for improved detection of 8-isoprostaglandin F2α/β and benzodiazepines in wastewater

Wastewater-based epidemiology is a tool incorporating biomarker analysis that can be used to monitor the health status of a population. Indicators of health include endogenous oxidative stress biomarkers and hormones, or exogenous such as alcohol and nicotine. 8-Iso-prostaglandin F2α/β is a biomarker of endogenous metabolism that can be used to measure oxidative stress in a community. Benzodiazepines are a harmful subclass of anxiolytics either prescribed or sourced illegally. The analysis of oxidative stress markers and uptake of benzodiazepines in wastewater may provide information about distress in the community. A method has been applied to detect 8-isoPGF2α/β and the illicit benzodiazepines clonazolam, flubromazolam and flualprazolam in addition to other prescribed benzodiazepines in wastewater. These substances have been sold as counterfeit pharmaceutical products, such as Xanax, which was formulated to include alprazolam.Deconjugation was initially performed on wastewater samples, followed by liquid-liquid extraction for isoprostanes and solid phase extraction for benzodiazepines to determine the total levels of these analytes. Limits of quantification were in the range of 0.5–2 ng/L for all the analytes except 8-isoPGF2α/β which was 50 ng/L. Stability, recovery and matrix effect studies were also conducted. Finally, this method was applied to influent wastewater from South Australia which showed the prevalence of 8-isoPGF2α/β and benzodiazepines.

Cancer-Associated Exosomal CBFB Facilitates the Aggressive Phenotype, Evasion of Oxidative Stress, and Preferential Predisposition to Bone Prometastatic Factor of Breast Cancer Progression.

Background Despite therapeutic advancements, metastasis remains a major cause in breast cancer-specific mortality. Breast cancer cells are susceptible to oxidative damage and exhibit high levels of oxidative stress, including protein damage, DNA damage, and lipid peroxidation. Some breast cancer risk factors may change the level of endogenous oxidative stress. Circulating exosomes play critical roles in tumorigenesis, distant metastasis, and poor prognosis in patients with breast cancer. Methods We used an online database to analyze the expression and prognostic value of core binding factor subunit β (CBFB) and oxidative stress–related targets in patients with breast cancer. Serum from healthy controls and patients with primary breast cancer or bone metastatic breast cancer in the bone was collected. Exosomes were isolated from the sera or cell culture media. We used an MDA-MB-436-innoculated tumor xenograft mouse model for silencing CBFB. Results Circulating exosomes from patients with breast cancer metastasis to the bone were rich in CBFB. The human mammary fibroblast cells HMF3A and fibroblasts derived from patient samples cocultured with exosomes had increased α-SMA and vimentin expression and IL-6 and OPN secretion. Similarly, nonmetastatic breast cancer cells cocultured with exosomes exhibited increased levels of certain markers, including vimentin, snail1, CXCR4, and Runx2, and the exosomes had high CBFB expression. Silencing CBFB in metastatic MDA-MB-436 and MDA-MB-157 cells resulted in suppressed migration and invasion and downregulation of vimentin, CXCR4, snail1, Runx2, CD44, and OPN. Conversely, CBFB overexpression resulted in upregulation of Runx2, vimentin, snail1, CD44, and OPN in nonmetastatic T47D and MCF12A cells. The CBFB-rich exosomes derived from MDA-MB-436 cells induced enhanced metastatic phenotypes in the low-metastatic T47D and MCF12A cell lines. Conclusion Our results revealed that CBFB may promote bone metastasis in patients with breast cancer. Of therapeutic relevance, targeting CBFB resulted in decreased tumor burden and bone metastasis, downregulation of bone metastasis markers, and impaired regulation of oxidative stress–related proteins NAE1 and NOS1.