Increase In Lipid Peroxidation Products Research Articles

Ecoengineering Solutions for the Impairment of Spreading and Growth of Invasive Spartina patens in Mediterranean Salt Marshes

The invasion of natural communities by non-indigenous species represents one of the most serious threats to biodiversity. Understanding the ecophysiology of invasive species can provide insights into potential physiological handicaps relative to native species. By doing so, we can leverage the development of ecoengineering solutions for the removal of non-indigenous species, preferably using non-chemical methods. Spartina patens is a known invasive species of cordgrass aggressively proliferating in Mediterranean salt marshes, producing impenetrable monospecific stands. As its occurrence is delimited by the upper high tide water level, we hypothesized that S. patens is intolerant to waterlogging. Therefore, we developed a field experiment where strands of S. patens were kept waterlogged over the entire tidal cycle for 30 days. At the end of the experimental period, plants in the trial plots exhibited severe stress symptoms at different physiological levels compared with control plots (no intervention). At the photobiological level, intervened plants exhibited lower efficiency in producing chemical energy from light, whilst at the biochemical level waterlogging impaired the antioxidant system and increased lipid peroxidation products. Furthermore, the application of chlorophyll a pulse amplitude modulated (PAM) fluorometry, a non-invasive technique, allowed us to evaluate the effectiveness of the implemented measures, being the tool that provided the best separation between the control and intervened population. Considering the physiological traits observed here, ecoengineering solutions based on increased waterlogging of S. patens stands, can be a low-cost and efficient measure to reduce the spreading and growth of this invasive species in the Mediterranean and other salt marshes worldwide with little disturbance.

The Enhanced Beneficial Effect of Extra Virgin Olive Oil Over Evening Primrose Oil on Oxidative Stress, and Liver Function in Male Arthritic Rats

Aims: Rheumatoid arthritis (RA) is characterized by the onset of oxidative stress. This study aimed to evaluate the enhancing of extra virgin olive (EVOO) and Evening primrose oil (EPO) on oxidative stress and liver enzymes in male Wistar rats and compare between them.
 Place and Duration: Faculty of Science biochemistry department, Between July 2018 and August 2018.
 Methodology: A Subcutaneous injection of 200 µl of Freund's complete adjuvant into a footpad of the right hind leg of Wistar male rats at two consecutive days induced RA. Rats received EVOO and EPO daily by oral gavage needle with gauge 18 at doses of 5 mg/kg b.wt./day. for 10 and 21 days. No loss was recorded in the experimental rats.
 Results: A significant depletion in serum Reduced glutathione content (GSH), glutathione peroxidase (GPX), and glutathione s transferase activities (GST) in arthritic rats compared to normal rats after 10 and 21 days of induction which improved significantly after 10 and 21 days of EPO and EVOO treatments. EPO and EVOO treatments for 21 days increased the GSH and GPX compared to 10 days treatments while no difference in GST activity. EVOO treatment improved GSH and GPX after 10 and 21 days than EPO treatment. The elevated uric acid levels in arthritic rats were markedly ameliorated as a result of EVOO and EPO treatment administration. Increased lipid peroxidation products (MDA), rheumatoid factor, and liver enzyme (Alanine transaminase ALT and Aspartate transaminase AST) were recorded in arthritic rats and they significantly progressed after EPO and EVOO treatments for 10 and 21 days but EVOO had the best effect at 21 days.
 Conclusion: EVOO and EPO showed significant antioxidant efficacies and improved affected liver enzymes due to rheumatoid arthritis onset. When comparing olive oil has more antioxidant properties than evening primrose oil, so we recommend more studies on olive oil combination with anti-arthritic medications to improve their efficacies with less toxicity.

Biochemical markers of oxidative stress in maize seedlings exposed to rose-grass aphids

We studied the influence of rose-grass aphid (Metopolophium dirhodum L.) infestation on the biochemical markers of oxidative stress in seedlings of two maize (Zea mays L.) varieties (relatively resistant Ambrozja and resistant Plomyk). We compared the generation of superoxide anion radicals O2-, level of hydrogen peroxide (H2O2), lipid peroxidation products (MDA) as well as markers of protein damage (protein-bound carbonyl groups). The studied parameters were measured at 24, 48, 72 and 96 h post-initial aphid infestation compared to the non-infested control seedlings. Our studies indicated that the rose-grass aphid feeding evoked oxidative stress in the maize seedlings. Investigated Z. mays cultivars exhibited excessive generation of superoxide anion radicals in response to insect treatments. Rose-grass aphid feeding increased the H2O2 level in maize tissues with similar levels observed at most periods post-infestation with M. dirhodum, also increased lipid peroxidation products with the maximal levels at 48 and 72 h for Ambrozja and 48, 72 and 96 h post-infestation for Plomyk varieties. Further at 48 and 72 h post-initial aphid infestation, there was an increase in protein bound carbonyl groups content in the maize seedlings after infestation with aphids.

3-Acetyldeoxynivalenol induces cell death through endoplasmic reticulum stress in mouse liver

Ingestion of food or cereal products contaminated by deoxynivalenol (DON) and related derivatives poses a threat to the health of humans and animals. However, the toxicity and underlying mechanisms of 3-acetyldeoxynivalenol (3-Ac-DON), an acetylated form of deoxynivalenol, have not been fully elucidated. In the present study, we showed that 3-Ac-DON caused significant oxidative damage, as shown by elevated aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactic dehydrogenase (LDH) in serum, increased lipid peroxidation products, such as hydrogen peroxide (H2O2) and malondialdehyde (MDA), decreased activities of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). In addition, 3-Ac-DON exposure led to elevated infiltrations of immune cell, increased apoptosis and autophagy in the liver. Interestingly, 3-Ac-DON-resulted apoptosis and liver injury were partially reduced by autophagy inhibitors. Further study showed that 3-Ac-DON-treated mice had altered ultrastructural changes of endoplasmic reticulum (ER), as well as enhanced protein levels of p-IRE1α, p-PERK, and downstream targets, indicating activation of unfolded protein response (UPR) in the liver. Importantly, 3-Ac-DON induced ER stress, oxidative damage, cell death, infiltration of immune cells, and increased mRNA levels of inflammatory cytokines were significantly abolished by 4-phenylbutyric acid (4-PBA), an ER stress inhibitor, indicating a critical role of UPR signaling for the cellular damage of the liver in response to 3-Ac-DON exposure. In conclusion, using mice as an animal model, we showed that 3-Ac-DON exposure impaired the function of liver, as shown by oxidative damage, cell death, and infiltration of immune cell, in which ER stress played an important role. Restoration of the ER function might be a preventive strategy to reduce the deleterious effect of 3-Ac-DON on the liver of animals.

Retraction: Cardiac mitochondrial oxidative stress and dysfunction induced by arsenic and its amelioration by diallyl trisulphide.

[This retracts the article DOI: 10.1039/c4tx00097h.].

Genotoxicity of esentai and ulken almaty rivers water on animal test-systems

Ecological monitoring, including water resources, is included in a set of measures for the rational use and protection of the environment. Currently, the assessment of water resources' genotoxicity and mutagenicity is an essential component of ecological monitoring.This research aimed to investigate water's genotoxicity from the Esentai and Ulken Almaty rivers flowing in Almaty. It was established that the content of Fe, Cu, Co, Ni, Pb, and Cd in the Almaty rivers water does not exceed the maximum permissible concentration (MPC). In contrast, zinc content in the Esentai and Ulken Almaty rivers' water exceeded the MPC, respectively, by 1.1 and 7.7-folds, manganese – 2.1, and 1.9-folds. It was found that water samples from the Esentai and Ulken Almaty rivers showed a DNA-damaging effect on the studied cells (bone marrow, liver, kidneys, and spleen) of laboratory mice. In the cells of the studied organs in the experimental groups, the frequency of single-strand DNA breaks a statistically significant increase compared to the control group's animal. The genotoxic action's organospecificity of the studied river waters on laboratory mice was established. According to their sensitivity to water's genotoxic effect, experimental mice's organs can arrange in the following order: spleen and bone marrow> liver> kidneys. An increase in lipid peroxidation products was found in the laboratory mice' liver that drank water from the Esentai and Ulken Almaty rivers. Thus, the results of the physicochemical, molecular-genetic, and biochemical analysis of water on animal test objects indicate the presence in the investigated natural surface waters of chemicals with genotoxic and toxic activity. Keywords:surface waters; heavy metals; DNA comet assay, organ specificity, lipid peroxidation

Apoptotic effects of valproic acid on miR-34a, miR-520h and HDAC1 gene in breast cancer

Identifying miRNAs involved in cancer and devising strategies to control their expression is a new therapeutic approach. Valproic acid (VPA) has attracted a lot of interest in cancer research. We evaluated the impact of VPA on the expression of miR-34a, miR-520h, and their target gene histone deacetylase 1 (HDAC1), as well as their relationship with apoptosis in breast cancer. First, through bioinformatics analyses, the possible target genes of miR-34a and miR-520h and their roles in apoptosis regulation were investigated. Then, miR-34a, miR-520h, and HDAC1 gene expression in tissues of breast cancer patients were determined using the qRT-PCR method. The anticancer impact of VPA on apoptosis and the expression levels of miR-34a, miR-520h, and HDAC1 gene were measured in MCF-7 and MDA-MB-231 cell lines. The bioinformatics analyses indicated that miR-34a and miR-520h might make a unique contribution in regulating the apoptosis pathway. The relative expression of miR-34a and miR-520h significantly decreased in cancer tissues, while the relative expression of HDAC1 increased. In the in vitro study, VPA led to apoptosis induction and increased lipid peroxidation products in breast cancer cells. Moreover, VPA increased the expression of miR- 34a and miR-520h and decreased HDAC1 expression in MCF-7 cells. In MDA-MB-231 cells, VPA decreased the expression of these miRNAs and increased the expression of HDAC1. It can be concluded that miR-34a and miR-520h are implicated in the apoptosis pathways, and thus, VPA can recruit as a possible option in breast cancer research due to its interference with epigenetic processes.

Study of prooxidant activity and some indicators of the pituitary-gonadal system in patients suffering from chronic endometritis

The state of lipid peroxidation and the oxidative modification of proteins in the blood of 29 women with chronic endometritis aged 27 to 40 years were studied. The control group consisted of 19 healthy women aged 27 to 44 years. The intensity of lipid peroxidation was estimated by the level of diene conjugates and malondialdehyde, the oxidative modification of proteins - by the level of carbonyl derivatives. It was shown that in the blood of women with chronic endometritis, the concentration of aliphatic aldehyde groups and 1,9 times the carbonyl groups in protein molecules increases by 3,3 times compared with the control group. A significant increase in diene conjugates by 34% and malondialdehyde in blood plasma and red blood cells by 47 and 43%, respectively, was established. The increase in lipid peroxidation products and oxidative protein modification in the blood indicates the development of oxidative stress in women suffering from chronic endometritis. Compared with healthy patients with chronic endometritis, a convincing tendency toward an increase in prolactin and anti- Muller hormone against a decrease in progesterone was revealed in the group compared to healthy ones. To predict possible complications in patients with chronic endometritis, it is advisable to study the indicators of protein and lipid peroxidation as markers of oxidative stress and the severity of the inflammatory process. In addition, such patients should be advised to take antioxidant drugs in combination with the basic therapy.

Study of free radicals (malondialdehyde) in pre-eclampsia and eclampsia in correlation with uric acid and total proteins

Introduction: Oxidative stress is a normal phenomenon in normotensive pregnancy; however, in preeclampsia, oxidative stress is exaggerated may result in a greater potential for endothelial oxidative damage. It has been reported that higher MDA (Malondialdehyde) /total antioxidant capacity (TAC) ratio is indicative of oxidative stress in women with pre-eclampsia. Materials and Methods: Prospective study was done for duration of 2 years i.e, from January 2015 to December 2017 in the department of Biochemistry at Kakatiya Medical College, Hanmakonda, CKM hospital Warangal. A total number of 60 pregnant women were included in the study. Among these, 20 pregnant women were clinically diagnosed as pre-eclampsia and 20 are eclamptic cases and the remaining 20 were selected as control group and are normotensive antenatal women who are also in third trimester of pregnancy. Results: The mean MDA, serum uric acid, 24 hr urinary protein were higher in pre-eclampsia and eclampsia compared to controls. Conclusion: Increased lipid peroxidation products levels clearly shows that oxidation stress is more in pre-eclampsia and eclampsia than in control subjects and it plays a significant role in etiopathogensis of PIH. Serum uric acid levels are significantly higher in cases than in controls and by estimating the uric acid levels we can assess the severity of the disease and we can avoid further progress of the disease process by early detection and prompt treatment. Total serum protein levels are drastically reduced in pre-eclampsia and eclampsia cases compared to controls. Keywords: MDA, Serum uric acid, Proteins, Eclampsia, Pre-eclampsia.

A Comparison of Hematological, Immunological, and Stress Responses to Capture and Transport in Wild White Rhinoceros Bulls (Ceratotherium simum simum) Supplemented With Azaperone or Midazolam.

Capture and transport are essential procedures for the management and conservation of southern white rhinoceroses (Ceratotherium simum simum), but are associated with stress-induced morbidity and mortality. To improve conservation efforts, it is crucial to understand the pathophysiology of rhinoceros stress responses and investigate drug combinations that could reduce these responses. In this study we measured rhinoceros stress responses to capture and transport by quantifying hematological and immunological changes together with adrenal hormone concentrations. We investigated whether the potent anxiolytic drug midazolam was able to mitigate these responses compared to azaperone, which is more commonly used during rhinoceros transport. Twenty three wild white rhinoceros bulls were transported for 6 h (280 km) within the Kruger National Park for reasons unrelated to this study. Rhinoceroses were immobilized with either etorphine-azaperone (group A, n = 11) or etorphine-midazolam (group M, n = 12) intramuscularly by darting from a helicopter. Azaperone (group A) or midazolam (group M) were re-administered intramuscularly every 2 h during transport. Serial blood samples were collected at capture (TC), the start of transport (T0) and after 6 h of transport (T6). Changes in hematological and immunological variables over time and between groups were compared using general mixed models. Increases in plasma epinephrine and serum cortisol concentrations indicated that rhinoceroses mounted a stress response to capture and transport. Packed cell volume decreased from TC to T6 indicating that stress hemoconcentration occurred at TC. Neutrophils progressively increased and lymphocytes and eosinophils progressively decreased from T0 to T6, resulting in an increase in neutrophil to lymphocyte ratio; a characteristic leukocyte response to circulating glucocorticoids. A reduction in serum iron concentrations may suggest the mounting of an acute phase response. Rhinoceroses experienced a decrease in unsaturated fatty acids and an increase in lipid peroxidation products at capture and toward the end of transport indicating oxidative stress. Midazolam, at the dose used in this study, was not able to mitigate adrenal responses to stress and appeared to directly influence leukocyte responses.

Predictive role of indicators of oxidative metabolism and elemental status in professional drivers of vehicles in the Northern region

Introduction. The predominant source of environmental pollution is motor transport, the release of pollutants which leads to excessive formation of free radicals. The most important metabolic part of the non-specifi c component of the syndrome of adaptation to adverse factors is the activation of free radical oxidation processes that contribute to the mobilization of protective reserves of the body. There is evidence that different groups of the population have different vulnerability to Prooxidant exposure to pollutants. The aim of the study is to establish correlations between the indicators of the pro — and antioxidant system and the elemental status of professional drivers living in the Khanty-Mansiysk Autonomous Region. Materials and methods. 182 male residents (32.6±6.2 years old) of the Khanty-Mansiysk Autonomous Region (KHMAR) were examined: 94 drivers of heavy trucks and fuel trucks and 88 employees. Free radical oxidation products (FRO) were determined in the blood: lipid hydroperoxides (LHP) and thiobarbituric acid active products (TBA-AP) using test kits from BCM Diagnostics (Germany) and AGAT (Russia). Total antioxidant activity (TAA) and thiol status (TS) were determined using commercial kits from Cayman Chemical and Immundiagnostik AG (Germany). The coefficient of oxidative stress (COS) was calculated using the formula: COS=LHP × TBA-AP / TAA × TS. The content of vitamin E was determined on the fl uorometer “Fluorat 02 — ABLF” of the company “Lumex” (Russia), vitamin C — using commercial kits of the company “Immundiagnostik AG” (Germany) on the analyzer of the company “Personal Lab” (Italy). The concentration of macro — and microelements (Ca, Se, Zn, Fe, Pb, Cd) was determined in the samples of AES — ISP and MS — ISP hair in TcMB (Moscow). Statistical processing was performed using the Microsoft Exsel software package and “Statistica 8.0”. For normal distribution, M, m, min, and max values were used. For abnormal distribution, both Me, 25 and 75 PS were used. Correlation relationships were studied using Spearman’s correlation coefficient. Differences at p<0.05 were considered reliable. Results. Drivers compared with employees have signifi cantly higher values of lipid peroxidation, Pb, Cd, Fe ( p <0.001–0.046), against the background of lower indicators of AOS, Ca, Se, Cu, Zn ( p <0.001–0.040). Direct relationships between TAA, vitamins E, C, Se and Zn (r=+0.312–0.802) and inverse relationships between TAA and Pb, Cd (r= –0.623–0.558) were found in drivers of KHMAR with more than 5 years of work experience, which is associated with the development of an oxidative imbalance, which is characterized by an increase in lipid peroxidation products. Conclusions. The relationship between the indicators of the state of oxidative metabolism, the availability of bioelements and antioxidant vitamins involved in the regulation of metabolic processes (p=0.048–0.001) has been established. Direct relationships between the indicators of total antioxidant activity, the glutathione system and the concentration of vitamins E, C, selenium and zinc (r=+0.312–0.802) and inverse relationships between the level of total antioxidant activity, thiol status, and toxic elements: lead and cadmium (r= –0.513–0.604) in the male population of KHMAR were revealed. More pronounced changes in adaptive metabolic reactions in the body of employees of motor transport companies who have a work experience of more than 5 years are associated with the development of an oxidative imbalance, which is characterized by an increase in POL products. The obtained data on the state of the oxidative status of the body of residents exposed to the negative eff ects of a chemical factor can be the basis not only for the formation of risk groups, the development and implementation of a set of scientifi cally-based preventive measures, but also for subsequent evaluation of the eff ectiveness of their use.

Simulated remote ischemic preconditioning inhibits Smad2 and enhances post‐hypoxic autophagy and survival of H9c2 cells

BackgroundCardiomyocyte apoptosis is considered as one the major forms of cell deaths of myocardial ischemia/reperfusion (I/R) injury. Remote ischemic preconditioning (RIPC) protects the cardiomyocytes from I/R injury that involves the enhancement of autophagy, but the underlying mechanism and especially the relationship with apoptosis has not been delineated. Smad2 is an important autophagy regulatory protein, but its role in RIPC is unknown.MethodsRat cardiac myoblast H9c2 cells hypoxia/reoxygenation (H/R) injury model was established with 6 hours of hypoxia followed by 12 hours of normoxia reoxygenation to mimic I/R injury. The cells in the conditioning group were exposed to 3 cycles of 10 minutes of alternating nitrogen‐flushed hypoxia and reoxygenation as stimulated RIPC (sRIPC) 24 hours before inducing prolonged H/R. The cell viability, oxidative damage, inflammatory markers, expressions of apoptosis and autophagy‐related proteins were assessed.ResultsH/R caused significant cell injury in untreated control H9c2 cells that was associated reduced autophagy (reduction in the ratio of LC3‐II to LC3‐I) and sRIPC enhanced post‐hypoxic cell survival, reduced reactive oxygen species formation and oxidative damage manifested as increased lipid peroxidation product Malondialdehyde (MDA), inhibited Smad2 transcriptional repressor activity, activated Beclin‐1 and autophagy but reduced apoptotic cell death (all p &lt; 0.05).ConclusionsIt is concluded that inhibition of Smad2 and the subsequent activation of autophagy may represent a mechanism by which sRIPC attenuate post‐hypoxic cardiomyocyte injury.Support or Funding InformationFunding: This study was supported by grants NSFC(81800245 and 81670770), and in part by Health and Medical Research Fund (HMRF, 05161826)

Effects of oxidative stress on liver, brain and spinal cord of rats using L-NAME and treated with hydroxyurea. A model of sickle cell complication

Purpose:To analyze the serum levels of nitric oxide and correlate them with the levels of thiobarbituric acid reactive substances (TBARS) in liver, brain and spinal cord of animals using L-NAME and treated with hydroxyurea.Methods:Eighteen male albino Wistar rats were divided into three groups. NG-nitro-L-arginine methyl ester (L-NAME) was intraperitoneally administered to induce oxidative stress. TBARS and plasma nitric oxide levels were analyzed in all groups. Histopathology of the liver and vascular tissue was performed.Results:Statistically significant differences were seen in liver, brain and spinal cord TBARS levels.Conclusions:Following the use of L-NAME, hepatic tissue increased the number of Kupffer cells as oxidative stress and inflammatory response increased. The use of L-NAME caused an increase in lipid peroxidation products and, consequently, in oxidative stress in animals. Hydroxyurea doses of 35 mg / kg / day reduced TBARS values in liver, brain and spinal cord.

OXIDATIVE AND ANTIOXIDANT PROCESSES IN THE FOCUS OF THE SKIN EXPOSED TO LOCAL ULTRAVIOLET IRRADIATION

The purpose of this study was to investigate the effect of local ultraviolet radiation on the content of lipid peroxidation products, lipofuscin, and the functioning of antioxidant enzymes in the skin of guinea pigs. Materials and methods. The studies were performed on 24 albino guinea pigs exposed to a single local ultraviolet radiation. The control group was made up of intact animals. The content of primary (diene conjugates) and secondary (TAC-active products) lipid peroxidation products, the activity of antioxidant enzymes (superoxide dismutase and catalase), and the content of lipofuscin were assessed in the skin in 2 hours, 4 hours, and on the 3rd and 8th day following the UV irradiation. Results. Under the influence of local ultraviolet radiation, all guinea pigs develop erythema (its peak is observed in 4 hours, and on the 3rd day), which disappears on the 8th day. There is a sharp enhancement of lipid peroxidation processes due to the accumulation of lipid peroxidation primary and secondary products in the skin of guinea pigs in all periods of the experiment. In parallel with the increase in lipid peroxidation products, there is a decrease in the activity of antioxidant enzymes (catalase and superoxide dismutase) in the focus of radiation. The content of lipofuscin in the skin progressively increases throughout the study period. Conclusions. The early erythema period following the local ultraviolet irradiation in the skin of guinea pigs, is characterized by increased content of diene conjugates and TBA-active products (in 2, 4 hours, on the 3rd day); decreased catalase activity and increased lipofuscin concentration (on the 3rd day after irradiation). The early post-erythema period (8th day) following the local ultraviolet irradiation is characterized by the accumulation of diene conjugates, TBA-active products and lipofuscin against the background of a decrease in the activity of catalase and superoxide dismutase in the skin of guinea pigs.

Choline supplementation alters egg production performance and hepatic oxidative status of laying hens fed high-docosahexaenoic acid microalgae

The purpose of the current study was to investigate the effect of choline as a means of increasing docosahexaenoic acid (22:6 n-3, DHA) deposition in egg yolks of hens fed a high-DHA microalgae product. Fifty-six, 26-wk-old, White Leghorn hens were kept in individual cages and randomly allocated to 1 of 4 dietary treatments, each with 7 replicate groups of 2 hens (n = 7 per treatment). The experimental diets were corn and soybean meal based, with 0% microalgae (control), 1% microalgae and no additional choline chloride (Alg), and Alg plus choline chloride at 0.1% (Ch0.1) and 0.2% (Ch0.2). The feeding trial lasted 16 wk. The data were fit as a general linear mixed model to generate least square means in response to diet. Variables measured multiple times during the study were fit as repeated measures. Using orthogonal contrasts, Alg was compared to control, and Ch0.1 and Ch0.2 were compared separately to Alg. Ch0.1 increased hen day egg production (P < 0.05) and Haugh unit (P < 0.05), and reduced feed conversion ratio (P < 0.05) compared to Alg, but Ch0.2 did not. Alg increased egg DHA (P < 0.001), phosphatidylethanolamine (P < 0.05), and phosphatidylcholine (P < 0.001) compared to control, but Ch0.1 or Ch0.2 had no effect compared to Alg (P > 0.05). In the liver, Alg increased lipid peroxidation products compared to control (P < 0.01), and Ch0.1 reduced them compared to Alg (P < 0.01). Both Ch0.1 and Ch0.2 increased hepatic concentrations of γ- (P < 0.05; P < 0.001) and α-tocopherol (P < 0.01; P < 0.001), and Ch0.1 increased γ-tocopherol concentration in eggs compared to Alg (P < 0.05). The results from the current study suggest that supplemental choline chloride in hen diets containing microalgae can improve production performance and egg quality, and protect the liver from oxidative stress.

Involvement of GPx4-Regulated Lipid Peroxidation in Idiopathic Pulmonary Fibrosis Pathogenesis.

The imbalanced redox status in lung has been widely implicated in idiopathic pulmonary fibrosis (IPF) pathogenesis. To regulate redox status, hydrogen peroxide must be adequately reduced to water by glutathione peroxidases (GPx). Among GPx isoforms, GPx4 is a unique antioxidant enzyme that can directly reduce phospholipid hydroperoxide. Increased lipid peroxidation products have been demonstrated in IPF lungs, suggesting the participation of imbalanced lipid peroxidation in IPF pathogenesis, which can be modulated by GPx4. In this study, we sought to examine the involvement of GPx4-modulated lipid peroxidation in regulating TGF-β-induced myofibroblast differentiation. Bleomycin-induced lung fibrosis development in mouse models with genetic manipulation of GPx4 were examined. Immunohistochemical evaluations for GPx4 and lipid peroxidation were performed in IPF lung tissues. Immunohistochemical evaluations showed reduced GPx4 expression levels accompanied by increased 4-hydroxy-2-nonenal in fibroblastic focus in IPF lungs. TGF-β-induced myofibroblast differentiation was enhanced by GPx4 knockdown with concomitantly enhanced lipid peroxidation and SMAD2/SMAD3 signaling. Heterozygous GPx4-deficient mice showed enhancement of bleomycin-induced lung fibrosis, which was attenuated in GPx4-transgenic mice in association with lipid peroxidation and SMAD signaling. Regulating lipid peroxidation by Trolox showed efficient attenuation of bleomycin-induced lung fibrosis development. These findings suggest that increased lipid peroxidation resulting from reduced GPx4 expression levels may be causally associated with lung fibrosis development through enhanced TGF-β signaling linked to myofibroblast accumulation of fibroblastic focus formation during IPF pathogenesis. It is likely that regulating lipid peroxidation caused by reduced GPx4 can be a promising target for an antifibrotic modality of treatment for IPF.

Na+/K+-ATPase level and products of lipid peroxidation in live cells treated with therapeutic lithium for different periods in time (1, 7, and 28days); studies of Jurkat and HEK293 cells.

Regulation of Na+/K+-ATPase in bipolar disorder and lithium therapy has been investigated for more than 40years. Contradictory results in this area may be caused by the difference between acute and long-term Li effects on cell metabolism and variance in responsiveness of different cell types. We compared the time-course of Li action focusing on Na+/K+-ATPase and lipid peroxidation in two widely different cell models-Jurkat and HEK293. Na+/K+-ATPase expression level was determined in cells cultivated in the absence or presence of 1mM Li for different time spans (1, 7, and 28days) using [3H] ouabain binding and immunoblot assay of α-subunit. In parallel samples, the formation of malondialdehyde (MDA) was quantified by HPLC, and 4-hydroxy-2-nonenal (4-HNE) protein adducts were determined by immunoblot. Cultivation of Jurkat cells in 1mM Li medium resulted in downregulation of Na+/K+-ATPase (decrease of [3H] ouabain-biding sites and intensity of immunoblot signals) in all Li-groups. In HEK293 cells, the decrease of Na+/K+-ATPase was observed after the acute, 1-day exposure only. The long-term treatment with Li resulted in Na+/K+-ATPase upregulation. MDA and 4-HNE modified proteins were decreased in Jurkat cells in all Li-groups. On the other hand, in HEK293 cells, MDA concentration was decreased after the acute, 1-day Li exposure only; the long-term cultivations, for 7 or 28days, resulted in a significant increase of lipid peroxidation products. The Li-induced decrease of lipid peroxidation products was associated with the decrease of Na+/K+-ATPase level and vice versa.

Mutagenic effects of sodium azide on pineapple micropropagant growth and biochemical profile within temporary immersion bioreactors

Sodium azide (NaN3) is widely used to induce mutagenesis within in vitro plant systems. However, since this mutagenesis is undirected, its unintended effects demand characterization. This study investigated the mutagenic effects of sodium azide (0-0.45 mM) on selected growth (shoot multiplication rate and shoot cluster fresh weight) and biochemical (aldehydes, chlorophylls, carotenoids and phenolics) parameters in pineapple micropropagants within temporary immersion bioreactors (TIBs). The content of soluble phenolics in the culture medium was also evaluated. Irrespective of the concentration NaN3 decreased shoot multiplication rate (by 87% relative to the control at 0.45 mM) and fresh weight (by 66% relative to the control at 0.45 mM). Levels of chlorophyll a and b, and soluble phenolics in the culture medium were also negatively correlated with NaN3 concentration. Interestingly, NaN3 application increased shoot carotenoid and soluble phenolic levels but had no significant effect on a range of established plant stress biomarkers: cell wall-linked phenolic levels, malondialdehyde and other aldehydes. Given that 0.19 mM NaN3 decreased shoot multiplication rate by 50% and resulted in propagants that displayed no morphologically abnormalities, increased levels of photoprotective pigments (relative to the control) and no significant increase in lipid peroxidation products, the mutagen can be used at this concentration to induce pineapple mutagenesis in TIB based studies aimed at producing agriculturally-useful mutants.

193 - Antioxidant activity of calcium-independent phospholipase A2γ in brain mitochondria

Mitochondrial calcium-independent phospholipase A2γ (iPLA2γ) belongs to a family of enzymes that participate in cellular signaling by simultaneously producing free fatty acids and lysophospholipids. We have shown previously that the activity of iPLA2γ is increased following the addition of oxidants, such as tert-butyl hydroperoxide (tBHP) or H2O2. We have also shown that iPLA2γ-liberated fatty acids induce H+ transport mediated by mitochondrial uncoupling proteins and mitochondrial adenine nucleotide translocase (ANT) in heart, lung and spleen mitochondria, leading to a decrease in the mitochondrial protonmotive force and subsequent decrease in mitochondrial superoxide production [1,2]. Here we tested the hypothesis that iPLA2γ serves similar antioxidant function in brain. Using brain mitochondria isolated from wild-type (WT) mice, we found that low micromolar concentrations of tBHP induced increase in respiration and a parallel decrease in mitochondrial superoxide and H2O2 production. These effects of tBHP were fully prevented by bovine serum albumin and inhibited by R-bromoenol lactone, a selective inhibitor of iPLA2γ, and were absent in brain mitochondria isolated from iPLA2γ-KO mice. Moreover, the tBHP-induced effects were fully inhibited by carboxyatractyloside, indicating the participation of ANT. In addition, we observed decrease in mRNA levels of selected antioxidant enzymes and increase in lipid peroxidation products in brain tissues homogenates of iPLA2γ-KO mice compared to the WT controls. Our results support the hypothesis of an antioxidant role of iPLA2γ in brain, consistent with iPLA2γ-dependent, ANT-mediated attenuation of mitochondrial superoxide production. Supported by LTAUSA17174

Pathophysiological Alterations of Redox Signaling and Endocannabinoid System in Granulocytes and Plasma of Psoriatic Patients.

Inflammatory granulocytes are characterized by an oxidative burst, which may promote oxidative stress and lipid modification both in affected tissues and on a systemic level. On the other hand, redox signaling involving lipid peroxidation products acting as second messengers of free radicals play important yet not fully understood roles in the pathophysiology of inflammation and various stress-associated disorders. Therefore, the aim of this study was to evaluate the onset of oxidative stress and alterations of enzyme-dependent lipid metabolism resulting from redox imbalance in granulocytes and plasma obtained from patients with psoriasis vulgaris or psoriatic arthritis in comparison to the healthy subjects. The results obtained revealed enhanced activity of pro-oxidant enzymes nicotinamide adenine dinucleotide phosphate (NADPH) and xanthine oxidases in granulocytes with a decrease of enzymatic and non-enzymatic antioxidants in the plasma of psoriatic patients. The nuclear factor erythroid 2–related factor 2 (Nrf2) and its regulators were increased in both forms of psoriasis while heme oxygenase 1 levels were increased only in psoriasis vulgaris. The redox imbalance was associated with decreased levels of phospholipids and of free polyunsaturated fatty acids but with enhanced activity of enzymes involved in lipid metabolism (phospholipase A2, acetylhydrolase PAF, cyclooxygenases 1 and 2) and increased lipid peroxidation products 4-hydroxynonenal, isoprostanes, and neuroprostanes. Increased endocannabinoids and G protein-coupled receptor 55 were observed in both forms of the disease while expression of the cannabinoid type 1 receptor (CB1) was increased only in patients with psoriatic arthritis, which is opposite to the cannabinoid type 2 receptor. This receptor was increased only in psoriasis vulgaris. Changes in protein expression promoted the apoptosis of granulocytes by increased caspases mainly in psoriasis vulgaris. This study indicates that inhibition of the Nrf2 pathway in psoriatic arthritis promotes a redox imbalance. In addition, increased expression of CB1 receptors leads to increased oxidative stress, lipid modifications, and inflammation, which, in turn, may promote the progression of psoriasis into the advanced, arthritic form of the disease.