Increased Glutathione Peroxidase Activity Research Articles

Foliar-selenium enhances plant growth and arsenic accumulation in As-hyperaccumulator Pteris vittata: Critical roles of GSH-GSSG cycle and arsenite antiporters PvACR3

It is known that selenium (Se) enhances plant growth and arsenic (As) accumulation in As-hyperaccumulator Pteris vittata, but the associated mechanisms are unclear. In this study, P. vittata was exposed to 50 μM arsenate (AsV) under hydroponics plus 25 or 50 μM foliar selenate. After 3-weeks of growth, the plant biomass, As and Se contents, As speciation, malondialdehyde (MDA) and glutathione (GSH and GSSG) levels, and important genes related to As-metabolism in P. vittata were determined. Foliar-Se increased plant biomass by 17 − 30 %, possibly due to 9.1 − 19 % reduction in MDA content compared to the As control. Further, foliar-Se enhanced the As contents by 1.9–3.5 folds and increased arsenite (AsIII) contents by 64 − 136 % in the fronds. The increased AsV reduction to AsIII was attributed to 60 − 131 % increase in glutathione peroxidase activity, which mediates GSH oxidation to GSSG (8.8 −29 % increase) in the fronds. Further, foliar-Se increased the expression of AsIII antiporters PvACR3;1–3;3 by 1.6 − 2.1 folds but had no impact on phosphate transporters PvPht1 or arsenate reductases PvHAC1/2. Our results indicate that foliar-Se effectively enhances plant growth and arsenic accumulation by promoting the GSH-GSSG cycle and upregulating gene expression of AsIII antiporters, which are responsible for AsIII translocation from the roots to fronds and AsIII sequestration into the fronds. The data indicate that foliar-Se can effectively improve phytoremediation efficiency of P. vittata in As-contaminated soils.

Effect of regular winter swimming on blood morphological, rheological, and biochemical indicators and activity of antioxidant enzymes in males

BackgroundExposure of the human body to cold water triggers numerous beneficial physiological changes. The study aimed to assess the impact of regular winter swimming on blood morphological, rheological, and biochemical indicators and activity of antioxidant enzymes in males.MethodsThe study involved 10 male winter swimmers (the same participants examined before the season and after the season) and 13 males (not winter swimming, leading a sedentary lifestyle) in the control group. Fasting blood was collected twice: in November and in March of the following year. Basic blood morphological indicators, red cell elongation index (EI) and aggregation index (AI), concentrations of testosterone, cortisol, urea, and creatinine, as well as plasma activity of antioxidant enzymes of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) were determined.ResultsThe data were collected from the same winter swimmers at the beginning and end of the season. Winter swimming resulted in a significant increase of EI values at a shear stress of 0.30 (p = 0.40), 0.58 (p < 0.001), 4.24 (p = 0.021), 8.23 (p = 0.001), 15.59 (p = 0.001), 30.94 (p = 0.004), and 60.00 Pa (p = 0.043); haemoglobin was lower than before the season (p < 0.027). No significant changes were observed in AI, AMP, T1/2, the levels of urea, creatinine, eGFR, testosterone, cortisol, or the activity of CAT or SOD. There was a statistically significant increase in GPx activity (p = 0.014) and increase in testosterone concentration (p = 0.035) in the group of winter swimmers examined before the season as compared with the control group. No statistically significant differences were found for the mean values of blood morphological indicators and other parameters.ConclusionsWinter swimming can prove to be a health-promoting factor in males, as indicated by a rise in the deformability of red blood cells in the blood vessel system after a full season of winter swimming, leading to better body oxygenation, and improves the antioxidant defence and testosterone concentration (within standard limits) in the group of winter swimmers examined before the season as compared with the control group. Winter swimming helps maintain appropriate levels of blood rheological indicators, urea, creatinine, eGFR, cortisol, testosterone, and activity of antioxidant enzymes.Trial registrationClinicalTrials.gov identifier NCT06223087, 15.01.2024.

Effects of Liquid Fructose Supplementation and Chronic Unpredictable Stress on Uterine Contractile Activity in Nonpregnant Rats.

Increased fructose consumption and chronic stress, the major characteristics of modern lifestyle, impact human health; however, the consequences of their combination on the uterus remain understudied. In this study, we investigated contractile activity, morphology, and intracellular activity of antioxidant enzymes in uteri from virgin Wistar rats subjected to liquid fructose supplementation and/or unpredictable stress over 9 weeks. Contractile activity and uterine response to oxytocin or adrenaline were examined ex vivo using isolated bath chambers. Fructose supplementation, irrespective of stress, affected uterine morphology by increasing endometrium while decreasing myometrium volume density, attenuated uterine response to increasing doses of oxytocin, and increased glutathione peroxidase activity. Stress, irrespective of fructose, attenuated dose-dependent adrenaline-induced uterine relaxation. Stress, when applied solely, decreased mitochondrial superoxide dismutase activity. In the combined treatment, irregular estrous cycles and both reduced response to oxytocin and to adrenaline (as a consequence of fructose consumption and exposure to stress), along with fructose-related alteration of uterine morphology, were detected. In conclusion, fructose and stress affect uterine contractile activity, irrespective of each other, by inducing completely distinct responses in isolated uteri. In the combined treatment, the effects of both factors were evident, suggesting that the combination exerts more detrimental effects on the uterus than each factor individually.

Epigallocatechin-3-gallate-synthesized gold nanoparticles modulate reactive oxygen species and antioxidant parameters in brain and heart tissues using a chicken embryo model

Chemically synthesized gold nanoparticles (AuNPs) come with drawbacks, such as biological toxicity and ecological imbalances. Nonetheless, a knowledge gap remains regarding their impact on oxidative and antioxidant parameters. Here, environmentally friendly AuNPs were synthesized using epigallocatechin-3-gallate (AuNPs-EGCG). The successful synthesis of AuNPs-EGCG were confirmed using ultraviolet–visible spectroscopy, Fourier-transform infrared spectroscopy, atomic force microscopy, and dynamic light scattering. Antioxidant activity was assessed using free radical 2,2-diphenyl-1-picrylhydrazyl, oxygen radical absorbance capacity, and ferric reducing antioxidant power assays, while cytotoxicity properties were evaluated in the NIH3T3 fibroblast cells. Furthermore, the impact of AuNPs-EGCG on oxidative stress was investigated in the hearts and brains of chicken embryos. AuNPs-EGCG exhibited no cytotoxicity and was not toxic for chicken embryos at higher concentrations. However, exposure to lower concentrations (100 and 30 μg/mL) caused an increase in reactive oxygen species (ROS) levels and a decrease in total antioxidant capacity in the heart and brain, resulting in a disturbance in the redox balance attributed to a reduction in catalase activity and glutathione (GSH) content, and an increase in glutathione peroxidase activity. In contrast, AuNPs-EGCG at 300 μg/mL promoted an increase in GSH levels and modulation of ROS, while also reducing vascular density in the chorioallantoic membrane. Furthermore, AuNPs-EGCG did not cause lipid or protein oxidation. The present study offers evidence that supports the investigation of how AuNPs-EGCG can modulate antioxidant defense mechanisms and assess the safety of phytoantioxidant-functionalized nanoparticles in vivo. This may lead to new and innovative strategies for the utilization of nanomaterials in biological systems.

The Role of Ayahuasca in Colorectal Adenocarcinoma Cell Survival, Proliferation and Oxidative Stress.

The psychedelic beverage ayahuasca is originally obtained by Banisteriopsis caapi (B. caapi) (BC) and Psychotria viridis (P. viridis) (PV). However, sometimes these plant species are replaced by others that mimic the original effects, such as Mimosa hostilis (M. hostilis) (MH) and Peganum harmala (P. harmala) (PH). Its worldwide consumption and the number of studies on its potential therapeutic effects has increased. This study aimed to evaluate the anticancer properties of ayahuasca in human colorectal adenocarcinoma cells. Thus, the maximum inhibitory concentration (IC50) of decoctions of MH, PH, and a mixture of these (MHPH) was determined. The activities of caspases 3 and 9 were evaluated, and the cell proliferation index was determined through immunocytochemical analysis (Ki-67). Two fluorescent probes were used to evaluate the production of oxidative stress and the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) was also evaluated. It was demonstrated that exposure to the extracts significantly induced apoptosis in Caco-2 cells, while decreasing cell proliferation. MH and MHPH samples significantly reduced oxidative stress and significantly increased glutathione peroxidase activity. No significant differences were found in SOD activity. Overall, it was demonstrated that the decoctions have a potential anticancer activity in Caco-2 cells.

Glutathione‐induced hydrogen sulfide enhances drought tolerance in sweet pepper (Capsicum annuum L.)

AbstractGlutathione (GSH) has been studied for its potential to enhance stress tolerance in plant systems, but the role of hydrogen sulfide (H2S) in GSH‐induced water stress tolerance in sweet pepper (Capsicum annuum L.) is still under investigation. This study explores how H2S and GSH modulate water stress tolerance in pepper plants, addressing a research gap. The joint effect of sodium hydrosulfide (NaHS), a donor of H2S, and GSH on water stress tolerance was determined through pre‐treatment with the H2S scavenger 0.1 mM hypotaurine (HT). Pepper seedlings were sprayed with 1.0 mM GSH or GSH + 0.2 mM NaHS once a week, with soil moisture content set at 80% and 40% for full irrigation and water stress conditions for a duration of 2 weeks. The results showed that water stress significantly reduced total plant dry weight, chlorophyll a and b content, Fv/Fm, leaf water potential, and relative water content by 50%, 56%, 33%, 27%, 52%, and 34%, while increasing hydrogen peroxide (H2O2), proline, and H2S levels by 152%, 134%, and77%, respectively. Treatment with GSH and NaHS reduced water stress‐induced H2O2 production and improved plant growth, photosynthetic traits, proline, and the activity of L‐cysteine desulfhydrase (L‐DES), leading to the generation of H2S content. GSH reduced NADPH oxidase (NOX), superoxide dismutase (SOD), and H2O2 but increased glutathione peroxidase (GPX) activities. The interaction of NaHS and GSH led to further reductions in NOX, SOD, and H2O2 values but increased GPX activity. The combined GSH and NaHS treatment increased nitric oxide (NO) production but decreased the activity of S‐nitrosoglutathione reductase (GSNOR), potentially accelerating S‐nitrosylation. Hypotaurine negated the positive impacts of GSH on water stress tolerance by reducing H2S concentration in pepper plants, but this was corrected by the concurrent application of NaHS and GSH + HT. Therefore, water stress tolerance requires H2S.

Curcumin mitigates ochratoxin A-induced oxidative stress and alters gene expression inbroiler chicken liver and kidney.

The study aimed to evaluate the effect of curcumin (CURC) supplementation on broiler chickens exposed to ochratoxin A (OTA), by examining biochemical parameters and the expression of glutathione redox system genes and their regulation. OTA reduced glutathione content in the liver while increasing glutathione peroxidase activity. CURC showed no significant effects. Kidney parameters remained mostly unaffected. Gene expression analysis revealed OTA-induced upregulation of KEAP1, NRF2, AHR, GPx4 and GSR genes in the liver. CURC supplementation led to the upregulation of GPx4and AHR genes with OTA+CURC treatment, resulting in the downregulation of GPx4, KEAP1, NRF2 and AHR genes compared to OTA treatment alone. In the kidney, GPx4 was downregulated, andNRF2and AHR were upregulated as an effect of OTA, while CURC upregulated the NRF2 gene only. OTA+CURC treatment led to the downregulation of GPx4, GSS and AHR genes compared to the control and downregulation of NRF2 and AHR genes compared to OTA. The results suggested that CURC is partly effective against OTA-induced oxidative stress and that the effect of OTA and CURC on the antioxidant response is regulated through the KEAP1-NRF2-ARE and AHR pathways.

Comparison of the potential toxicity induced by microplastics made of polyethylene terephthalate (PET) and polylactic acid (PLA) on the earthworm Eiseniafoetida

A growing number of studies have demonstrated that microplastic (MP) contamination is widespread in terrestrial ecosystems. A wide array of MPs made of conventional, fossil-based polymers differing in size and shape has been detected in soils worldwide. Recently, also MPs made of bioplastics have been found in soils, but there is a dearth of information concerning their toxicity on soil organisms. This study aimed at exploring the potential toxicity induced by the exposure for 28 days to irregular shaped and differently sized MPs made of a fossil-based (polyethylene terephthalate – PET) and a bioplastic (polylactic acid – PLA) polymer on the earthworm Eisenia foetida. Two amounts (1 g and 10 g/kg of soil, corresponding to 0.1% and 1% of soil weight) of both MP types were administered to the earthworms. A multi-level approach was used to investigate the MP-induced effects at sub-individual and individual level. Changes in the activity of antioxidant and detoxifying enzymes, as well as in lipid peroxidation levels, were investigated at specific time-points (i.e., 7, 14, 21 and 28 days) as sub-individual responses. Histological analyses were performed to assess effects at tissue level, while the change in digging activity was considered as a proxy of behavioral effects. Earthworms ingested MPs made of both the polymers. MPs made of PET did not induce any adverse effect at none of the biological levels. In contrast, MPs made of PLA caused the modulation of earthworms’ oxidative status as showed by a bell-shaped activity of superoxide dismutase coupled with an increase in glutathione peroxidase activity. However, neither oxidative and tissue damage, nor behavioral alteration occurred. These findings suggest that the exposure to bio-based MPs can cause higher toxicity compared to fossil-based MPs.

Time-restricted feeding prevents ionizing radiation-induced hematopoietic stem cell damage by inhibiting NOX-4/ROS/p38 MAPK pathway

Ionizing radiation (IR)-induced damage to the hematopoietic system is a prominent symptom following exposure to total body irradiation (TBI). The exploration of strategies aimed at to mitigating radiation-induced hematopoietic damage assumes paramount importance. Time-restricted feeding (TRF) has garnered attention for its beneficial effects in various diseases. In this study, we evaluated the preventive effects of TRF on TBI-induced hematopoietic damage. The results suggested that TRF significantly enhanced the proportion and function of hematopoietic stem cells in mice exposed to 4 Gy TBI. These effects might be attributed to the inhibition of the NOX-4/ROS/p38 MAPK pathway in hematopoietic stem cells. TRF also influenced the expression of nuclear factor erythroid2-related factor 2 and increased glutathione peroxidase activity, thereby promoting the clearance of reactive oxygen species. Furthermore, TRF alleviated aberrations in plasma metabolism by inhibiting the mammalian target of rapamycin. These findings suggest that TRF may represent a novel approach to preventing hematopoietic radiation damage.

Propolis Protects GC-1spg Spermatogonial Cells against Tert-Butyl Hydroperoxide-Induced Oxidative Damage.

Propolis is a natural resin produced by honeybees with plenty of pharmacologic properties, including antioxidant activity. Oxidative stress disrupts germ cell development and sperm function, with demonstrated harmful effects on male reproduction. Several natural antioxidants have been shown to reduce oxidative damage and increase sperm fertility potential; however, little is known about the effects of propolis. This work evaluated the role of propolis in protecting spermatogonial cells from oxidative damage. Propolis' phytochemical composition and antioxidant potential were determined, and mouse GC-1spg spermatogonial cells were treated with 0.1-500 µg/mL propolis (12-48 h) in the presence or absence of an oxidant stimulus (tert-butyl hydroperoxide, TBHP, 0.005-3.6 µg/mL, 12 h). Cytotoxicity was assessed by MTT assays and proliferation by Ki-67 immunocytochemistry. Apoptosis, reactive oxygen species (ROS), and antioxidant defenses were evaluated colorimetrically. Propolis presented high phenolic and flavonoid content and moderate antioxidant activity, increasing the viability of GC-1spg cells and counteracting TBHP's effects on viability and proliferation. Additionally, propolis reduced ROS levels in GC-1spg, regardless of the presence of TBHP. Propolis decreased caspase-3 and increased glutathione peroxidase activity in TBHP-treated GC-1spg cells. The present study shows the protective action of propolis against oxidative damage in spermatogonia, opening the possibility of exploiting its benefits to male fertility.

Noni (Morinda Citrifolia) Ethanol Extract Lowered Blood Glucose Levels, Increased Glutathione Peroxidase Activity, And Decreased Malondialdehyde in White Rats Model of Diabetes

Diabetes mellitus can increase oxidative stress and damage cells. Noni fruit has antibacterial, antifungal, antitumor, analgesic, hypotensive, and anti-inflammatory benefits, can boost immunity, and has antioxidant content. Noni contains phenolic compounds (anthraquinones, acuities, asperulosides, and scopoletin), organic acids (capric and caprylic acids), and alkaloids (xeronine). The effect of noni ethanol extract can significantly reduce blood glucose (P&lt;0.05) of the T2 group (177.00±137.78) and T3 (159.40±86.53) when compared to the C+ group (511.00±131.45). The T1 group (387.40±170.06) had no significant difference (P&gt;0.05) when compared to the C+ group (511.00±131.45), but there was a decrease in the average yield at T1 (387.40±170.06). Serum malondialdehyde (MDA) examination showed a significant decrease (p&lt;0.05) in T1 (1188.32±93.41), while in T2 (1385.35±38.65) and T3 (1460.32±42.51) was not significant (p&lt;0.05). Examination of serum glutathione peroxidase (GPX) showed a significant decrease in T1 (119.97±37.45), there was a decrease in GPX levels, while in the T2 group (236.14±6.05) and T3 (185.24±43.07), there was no decrease. Noni ethanol extract can lower blood glucose levels, reduce Malondialdehyde levels, and prevent increased activity of the enzyme glutathione peroxidase. Flavonoid compounds in noni ethanol extract can avoid increased blood glucose and reduce free radicals formed due to hyperglycemia conditions.

Redox status of blood lymphocytes in patients with soft tissue sarcomas

Introduction. The proven significance of free radical disorders in oncopathology determines the relevance of their study in soft tissue sarcomas (STS), which are characterized by a tendency to recurrence and high mortality of patients.Aim. To study the indicators of free radical oxidation and antioxidant protection in blood lymphocytes in primary and recurrent STS, depending on the sex and age of patients.Materials and methods. In 51 patients with primary STS, T2bN0M0 (17 men and 34 women) and in 34 patients (14 men and 20 women) with relapses, the level of lipid peroxidation products – malondialdehyde and diene conjugates, activities of superoxide dismutase and glutathione peroxidase, total peroxidase activity, the level of reduced glutathione were studied by spectrophotometric methods. Patients were divided by age: ≤45 years and &gt;45 years. The comparison groups (donors) consisted of 12 men and 17 women divided into the same age subgroups.Results. In men &gt;45 years old with primary sarcomas, there was an increase in diene conjugates by 2.2 times, with relapses by 2.4 times, and in young men - only with relapses by 2.6 times. The level of malondialdehyde in men did not change with primary sarcomas, with relapses it was reduced in both age groups by 2.4–2.6 times. In women with primary STS, there was an increase in most of the studied parameters in both age groups by 1.6–1.9 times. The increase in diene conjugates level and superoxide dismutase activity was the most pronounced (&gt;3 times) in patients of the older age group. The increase in glutathione peroxidase activity in primary STS in young women was 2.3 times, and in the older age group in patients of both sexes it was 5 times. In half of the women with relapses developed no earlier than 3 years after treatment, a decrease in both lipid peroxidation products by 2.6–3.4 times was found, and in all women almost 4-fold activation of superoxide dismutase and 8-fold glutathione peroxidase with an increase in the level of reduced glutathione by 7 times took place, which was significantly higher than in men. For women of the older age group, a 3-fold increase in the ratio of superoxide dismutase/total peroxidase activity is characteristic for primary STS and almost 5-fold for recurrence.Conclusion. In primary STS, the activation of lipid peroxidation products and antioxidant enzymes in women is more pronounced than in men. Changes in most indicators are more typical for patients of older age groups, in which relapse was accompanied by a decrease in malondialdehyde in patients of both sexes and maximum activation of superoxide dismutase and glutathione peroxidase in women.

Chronic Thermal Acclimation Effects on Critical Thermal Maxima (CTmax) and Oxidative Stress Differences in White Epaxial Muscle between Surface and Cave Morphotypes of the Mexican Cavefish (Astyanax mexicanus).

AbstractIn the face of increasing environmental temperatures, operative differences between mitochondrial function and whole-animal phenotypic response to the environment are underrepresented in research, especially in subtemperate ectothermic vertebrates. A novel approach to exploring this connection is to examine model species that are genetically similar but that have different whole-animal phenotypes, each of which inhabits different environments. The blind Mexican cavefish (Astyanax mexicanus) has the following two morphotypes: a surface form found in aboveground rivers and an obligate cave-dwelling form. Each morphotype inhabits vastly different thermal and oxygen environments. Whole-animal and mitochondrial responses to thermal acclimation and oxidative stress, with respect to increasing temperatures, have not been previously determined in either morphotype of this species. Here, we chronically acclimated both morphotypes to three temperatures (14°C, 25°C, and 31°C) to establish potential for acclimation and critical thermal maxima (CTmax) for each morphotype of this species. After measuring CTmax in six cohorts, we additionally measured enzymatic antioxidant capacity (catalase, superoxide dismutase, and glutathione peroxidase activities), peroxyl scavenging capacity, and lipid peroxidation damage in white epaxial muscle for each individual. We found a significant effect of acclimation temperature on CTmax (, ) but no effect of morphotype on CTmax (, ). Additionally, we found that morphotype had a significant effect on glutathione peroxidase activity, with the surface morphotype having increased glutathione peroxidase activity compared with the cave morphotype (, ). No other oxidative stress variable demonstrated significant differences. Increases in CTmax with chronic thermal acclimation to higher temperatures suggests that there is some degree of phenotypic plasticity in this species that nominally occupies thermally stable environments. The decreased glutathione peroxidase activity in the cave morphotype may be related to decreased environmental oxygen concentration and decreased metabolic rate in this environmentally constrained morphotype compared to in its surface-living counterparts.

Enzymatic responses reveal different physiological strategies employed by eurytolerant fish during extreme hot and cold cycling acclimation temperatures

Heat waves and cold snaps are projected to rise in magnitude, duration, interval, and harshness in the coming years. The current literature examining thermal impacts on the physiology of organisms rarely uses chronic, variable thermal acclimations despite the fact that climate change predictions project a more variable environment. If we are to determine species’ susceptibility to climate change, chronic and variable lab acclimations should be prioritized. Here, we acclimated the eurytolerant sheepshead minnow (Cyprinodon variegatus) to two extreme cycling thermal regimes: one warm [resting 27 °C with a spike to 33 °C for 8 h daily], one cold [resting 6.5 °C with a spike to 12 °C for 8 h daily], and three chronically stable conditions (10, 22, and 30 °C) for comparison. We measured enzymatic antioxidants (catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)), total antioxidant capacity, lipid peroxidation (LPO) damage, and citrate synthase (CS) activity in white epaxial muscle. Of particular note, we found significant increases in log CAT activity and SOD concentration in the warm cycling temperatures, and significant increases in GPx activity in the cold cycling temperatures. We found no significant accumulation of LPO damage in any of our thermal acclimation treatments. Thus, sheepshead minnows demonstrate two particularly different mechanisms towards dealing with thermal variation in low and high temperatures. The enzymatic differences between low and high cycling temperatures may define pathways of eurytolerant organisms and how they may survive predicted variability in thermal regimes.

Selenium homeostasis in human brain cells: Effects of copper (II) and Se species

BackgroundBoth essential trace elements selenium (Se) and copper (Cu) play an important role in maintaining brain function. Homeostasis of Cu, which is tightly regulated under physiological conditions, seems to be disturbed in Alzheimer´s (AD) and Parkinson´s disease (PD) patients. Excess Cu promotes the formation of oxidative stress, which is thought to be a major cause for development and progression of neurological diseases (NDs). Most selenoproteins exhibit antioxidative properties and may counteract oxidative stress. However, expression of selenoproteins is altered under conditions of Se deficiency. Serum Se levels are decreased in AD and PD patients suggesting Se as an important factor in the development and progression of NDs. The aim of this study was to elucidate the interactions between Cu and Se in human brain cells particularly with respect to Se homeostasis. MethodsFirstly, modulation of Se status by selenite or SeMet were assessed in human astrocytes and human differentiated neurons. Therefore, cellular total Se content, intra- and extracellular selenoprotein P (SELENOP) content, and glutathione peroxidase (GPX) activity were quantified. Secondly, to investigate the impact of Cu on these markers, cells were exposed to copper(II)sulphate (CuSO4) for 48 h. In addition, putative protective effects of Se on Cu-induced toxicity, as measured by cell viability, DNA damage, and neurodegeneration were investigated. ResultsModulation of cellular Se status was strongly dependent on Se species. In detail, SeMet increased total cellular Se and SELENOP content, whereas selenite led to increased GPX activity and SELENOP excretion. Cu treatment resulted in 133-fold higher cellular Cu concentration with a concomitant decrease in Se content. Additionally, SELENOP excretion was suppressed in both cell lines, while GPX activity was diminished only in astrocytes. These effects of Cu could be partially prevented by the addition of Se depending on the cell line and Se species used. While Cu-induced oxidative DNA damage could not be prevented by addition of Se regardless of chemical species, SeMet protected against neurite network degeneration triggered by Cu. ConclusionCu appears to negatively affect Se status in astrocytes and neurons. Especially with regard to an altered homeostasis of those trace elements during aging, this interaction is of high physiological relevance. Increasing Cu concentrations associated with decreased selenoprotein expression or functionality might be a promoting factor for the development of NDs.

Effect of olive oil on oxidative and DNA damage induced by imidacloprid

The current study aimed to evaluate the effect of olive oil (OLO) on the genotoxicity of imidacloprid (IMI). Rats were divided into four groups: control group, IMI group that was exposed to 22.5 mg/kg b.w. IMI for 4, 8, and 12 weeks; OLO before IMI group – dosed orally with OLO at a dose of 10 mL/kg body weight for two weeks before IMI exposure of 4, 8, and 12 weeks. The OLO after IMI group was treated with OLO in a dose of 10 mL /kg body weight for two weeks after IMI exposure of 4, 8, and 12 weeks. Malondialdehyde (MDA) and glutathione peroxidase (GPx) levels were measured in blood serum. The bone marrow from the femur was collected for the comet assay. The results revealed that exposure to IMI induced DNA damage, which was associated with increased blood MDA level and decreased GPx activity. However, treatment with OLO resulted in decreasing both DNA damage and MDA level while increasing GPx activity. On the other hand, pre-treatment with OLO was effective in decreasing the DNA damaging effect of IMI.

Effects of Epigallocatechin Gallate on the Cytotoxicity of Epirubicin-HCl in Lung Cancer Cells

Background: Studies have shown that epigallocatechin-3-gallate (EGCG), which is present in green tea at a higher rate than other components, has an additive or synergistic cytotoxic effect when applied with different anticancer drugs and reduces the side effects caused by anticancer drugs. It is known that the order of administration of drugs in combined applications also affects cytotoxicity. In this context, in our study, the most effective application sequence was determined by evaluating the cytotoxic responses of epirubicin-HCl and EGCG according to the different application order in A-549 cells (NSCLC). Methods: To demonstrate the apoptotic activity, we detected changes in mRNA ratios of Bax, a pro-apoptotic gene, and Bcl-2, an anti-apoptotic gene, (Bax/Bcl2), as well as changes in the activity of caspase 3/7 enzyme. To demonstrate the effect of oxidative stress generation, we investigated changes in glutathione peroxidase activity. Results: It was observed that the cell viability of A-549 cells exposed to different concentrations of epirubicin-HCl and EGCG for 48 h decreased depending on the concentration increase. According to the results of cell viability in cells to which epirubicin-HCl (&lt;IC50) and EGCG (&lt;IC50) were treated with together, and the combination index (CI) value calculations, the most effective combination concentrations were determined to be IC20 Epirubicin-HCl and IC10 EGCG. LDH activities were found higher in epirubicin-HCl + EGCG treatment than epirubicin-HCl alone treatment compared to control groups. Treatment of epirubicin-HCl with EGCG was found to be more effective in increasing glutathione peroxidase activity than epirubicin-HCl alone. Both of epirubicin-HCl alone and combination traetments caused increase in Bax/Bcl-2 ratio in A-549 cells. Conclusion: Combination therapy of epirubicin-HCl with EGCG may be a light in the future for lung cancer patients who are tried to be treated with conventional chemotherapy drugs but cannot achieve the desired success.

Anti-leishmanial, immunomodulatory and anti-oxidative activity of quercetin against cutaneous leishmaniasis caused by Leishmania major

Objective: To evaluate the in vitro and in vivo efficacy of quercetin and its immunomodulatory and anti-oxidative activity against Leishmania major (L. major). Methods: L. major promastigotes and amastigotes were incubated with different concentrations of quercetin to estimate EC50. For in vivo study, the base of tails of mice was infected with L. major. After developing ulcers in the inoculation site, mice were treated with 50 mg/kg quercetin orally for 28 consecutive days. The wound-healing potential of quercetin was evaluated by histopathological analysis of tissue sections stained by hematoxylin and eosin as well as Masson's trichrome. In addition, the levels of tumor necrosis factor-α, interleukin-6, malondialdehyde, and adiponectin, the ferric reducing ability of plasma, as well as superoxide dismutase and glutathione peroxidase activities were measured. Results: The EC50 values of quercetin against L. major promastigotes and intracellular amastigotes were 0.27 and 0.85 μM, respectively. Histopathological analysis showed that fewer inflammatory cells, more fibroblasts, and more collagen deposition were observed in tissue sections of quercetin-treated mice. In addition, treatment with quercetin markedly increased glutathione peroxidase activity, the ferric reducing ability of plasma and adiponectin levels while decreasing malondialdehyde, interleukin-6, and tumor necrosis factor-α levels. Conclusions: Quercetin shows anti-leishmanial activity, immunomodulatory, anti-oxidative, and anti-inflammatory effects. Therefore, it may be further explored as an effective drug in treating leishmaniasis.

Effect of omega-3 polyunsaturated fatty acid supplementation on oxidative stress parameters and sex hormone levels of modern genotype sows.

Sows are exposed to severe stress and hormonal challenges during their whole productive life. As polyunsaturated fatty acids play an important role in immune and reproductive functions, with a better understanding of their role in breeding sows' nutrition, improved performance and more sustainable pig production can be achieved. In this study, we investigated the effects of omega-6 and omega-3 fatty acid supplementation on the antioxidant status and hormone levels of sows. A total of 48 Danish Large white × Danish Landrace sows were supplemented either with sunflower oil (SO) as a control group or with fish oil (FO) as experimental group at the same dose of 10g/kg feed. Blood samples were collected on day 14 of lactation, 5 days after weaning (insemination), and 30 days after insemination. To estimate antioxidant and reproductive effects, the amounts of reduced glutathione (GSH), thiobarbituric acid reactive substance, the activity of glutathione peroxidase (GPx), serum 17β oestradiol (E2), progesterone (P4), and 6-keto prostaglandin F1α (6-keto PGF1α) levels were investigated. FO-based supplementation increased GPx activity on day 14 of lactation. Five days after weaning, the concentration of GSH in FO-fed sows was significantly higher than that in SO-fed sows. The E2 content of blood was significantly lower in the experimental group than in the control group for two of the three examined periods (day 14 of lactation and 30 days after insemination), whereas P4 levels were significantly higher in the experimental group 5 days after weaning. We found that 6-keto PGF1α levels were systematically lower in the experimental group throughout the trial. This study provides evidence of the major impact of omega-6 and -3 fatty acids on the tested hormone levels, which serve as precursors for the production of E2 and P4 but have an opposite effect on PGF2α production.

Evaluation of Toxic Effects Induced by Sub-Acute Exposure to Low Doses of α-Cypermethrin in Adult Male Rats.

To contribute new information to the pyrethroid pesticide α-cypermethrin toxicity profile, we evaluated its effects after oral administration to Wistar rats at daily doses of 2.186, 0.015, 0.157, and 0.786 mg/kg bw for 28 days. Evaluations were performed using markers of oxidative stress, cholinesterase (ChE) activities, and levels of primary DNA damage in plasma/whole blood and liver, kidney, and brain tissue. Consecutive exposure to α-cypermethrin affected the kidney, liver, and brain weight of rats. A significant increase in concentration of the thiobarbituric acid reactive species was observed in the brain, accompanied by a significant increase in glutathione peroxidase (GPx) activity. An increase in GPx activity was also observed in the liver of all α-cypermethrin-treated groups, while GPx activity in the blood was significantly lower than in controls. A decrease in ChE activities was observed in the kidney and liver. Treatment with α-cypermethrin induced DNA damage in the studied cell types at almost all of the applied doses, indicating the highest susceptibility in the brain. The present study showed that, even at very low doses, exposure to α-cypermethrin exerts genotoxic effects and sets in motion the antioxidative mechanisms of cell defense, indicating the potential hazards posed by this insecticide.