Oxidative Modification Of Lipids Research Articles

ПРОЦЕССЫ ЛИПОПЕРОКСИДАЦИИ И СИСТЕМА АНТИОКСИДАНТНОЙ ЗАЩИТЫ В КРОВИ ПУПОВИНЫ НОВОРОЖДЕННЫХ ПРИ ЦИТОМЕГАЛОВИРУСНОЙ ИНФЕКЦИИ В ПЕРИОД БЕРЕМЕННОСТИ

The aim of the work is to study the activity of lipoperoxidation processes and antioxidant protection system in the umbilical cord blood of newborns from CMV-seropositive women with exacerbation of infection in the third trimester of pregnancy. Lipid peroxidation activity and antioxidant status in 30 newborns from CMV-seropositive women with exacerbation of infection in the third trimester of pregnancy and in 25 from CMV-seronegative women were studied. Erythrocytes were used to determine the products of oxidative modification of lipids; antioxidant status was evaluated in the blood plasma of the umbilical vein. The content of TBK-active products was determined by fluorometric method, lysophosphatidylcholine by thin-layer chromatography, arachidonic acid by gas-liquid chromatography. Antioxidant status was assessed by α-tocopherol content and superoxide dismutase activity. Registration of optical densities and fluorescence was carried out using a spectrofluorometer. The study found an increase in the content of red blood cells of the umbilical cord of newborns from CMV-seropositive women with an exacerbation of infection in the third trimester of pregnancy of TAC-active products in 2.1 times (p˂0.001), of lysophosphatidylcholine in 1.9 times (p˂0.001) and of arachidonic acid in 1.5 times (p˂0.001). The antioxidant status of umbilical cord blood was characterized by 1.5 times decrease in α-tocopherol (p<0.01) and 1.3 times decrease in superoxide dismutase activity (p˂0.001) compared with similar indices in the group of newborns from CMV-seronegative women. The results of the study show that the exacerbation of cytomegalovirus infection in the third trimester of pregnancy is accompanied by the development of oxidative stress and tension in the system of antioxidant protection in the blood of the umbilical cord of newborns due to increased consumption of α-tocopherol and suppression of superoxide dismutase activity.

Oxidative Modification of Lipids and Lipoproteins in Steady State Sickle Cell Anemic Patients from South-Eastern Nigeria

Sickle cell anemia is a genetic disease associated with constant medical crises. These crises are due to many biochemical and hematological changes arising from multi-organ damages. This study was aimed to assess changes in the plasma levels of lipids and specific lipoproteins in sickle cell anemia patients who were in their steady states. The study is a cross-sectional one involving 75 patients with sickle cell anemia, who were in their stable states while attending their routine check-up at the sickle cell clinic of University of Nigeria Teaching Hospital, Enugu, Nigeria and 72 age and sex-matched apparently healthy school children with normal blood genotypes. The patients were made up of 40 males and 35 females while the controls were 36 males and 36 females. The results of the study showed that patients have the following; total cholesterol 135 ± 38.6mg/dL, HDL-cholesterol 22.7 ± 8.1mg/dL, LDL-cholesterol 91.4 ± 41.2mg/dL, VLDL-cholesterol 20.5 ± 5.0mg/dL and triglycerides 102.7 ± 25.2mg/dL, while the results from the controls were; total cholesterol 162.2 ± 27.4mg/dL, HDL-cholesterol 36.6 ± 7.9mg/dL, LDL-cholesterol 100.2 ± 23.9mg/dL, VLDL-cholesterol 25.4 ± 3.7mg/dL and triglycerides 127.0 ± 18.4mg/dL. These results showed that there were significant decreases (p 0.05) between the parameters obtained in males and females in both patients and controls. Lipids and lipoproteins were significantly reduced in steady state sickle cell anemia, causing the patients to depend mainly on limited carbohydrates and proteins for the provision of energy. This may account for constant lack of energy as well as the frail and fragile appearances of these patients.

Oxidative stress and antioxidants: Distress or eustress?

Oxidative stress, a signal which affects redox balance and induces oxidative modification of biological molecules, may have multiple faces. Reactive oxygen and related species (ROS) protect us from invading xenobiotics and act as physiological redox signaling messenger. The production of ROS is tightly regulated and the reactions are selective. On the other hand, ROS produced by unregulated manner induce random oxidative modification of lipids, proteins, and nucleic acids, which gives rise to deleterious effects and has been implicated in the pathogenesis of many diseases. Thus, ROS may become good stress (eustress) or bad stress (distress). Unsaturated lipids such as linoleic acid (LA), arachidonic acid (AA), and cholesterol, both free and ester forms, are vulnerable to oxidation by multiple oxidants to give diverse products. Lipid hydroperoxides, the major primary product, are toxic per se and may exert deleterious effects by producing reactive secondary products including HNE. We aerobic organisms are protected from lipid oxidation products by inhibiting their production and by inducing adaptive response. It has been shown that multiple antioxidant compounds and enzymes are induced by lipid oxidation products to prepare for subsequent deleterious oxidative stress. The lipid oxidation products produced by random manner may not be physiological signaling messenger, but rather xenobiotics. It has been observed that levels of these products are associated with the onset and progress of diseases such as atherosclerosis. We are protected from oxidative stress by an array of defense system in which multiple antioxidants with diverse functions play their respective roles including reduction of hydrogen peroxide and hydroperoxides, sequestration of metal ions, scavenging of reactive oxidants, repair of damage, and excretion of toxic products. Scavenging of ROS is one of the important functions of antioxidants. It may be noted that the efficacy of scavenging oxidants depends on the nature of oxidants. Further, it is unlikely that antioxidants scavenge such oxidants that act as physiologically important signaling messenger. Interestingly, higher levels of lipid oxidation products produced by peroxyl radicals, peroxynitrite, hypochlorite, 15-lipoxygenase, and singlet oxygen have been found in atherosclerotic lesions than in normal arteries and in plasma of patients than healthy subjects, suggesting that multiple antioxidants are required to inhibit deleterious lipid oxidation in vivo.

Abstract 4902: Oxidized low-density lipoprotein is a potentially potent mediator of proteasome inhibitor resistance in multiple myeloma

Abstract Multiple myeloma (MM) is a malignancy of plasma cells that accumulate in the bone marrow. While treatment advances, particularly proteasome inhibitors (PIs) and immunomodulatory drugs, have improved survival, MM is incurable. Obesity and insulin resistance are established risk factors for MM mortality. Oxidized low-density lipoprotein (OxLDL), a key atherogenic factor that is elevated in obesity, has emerged as a risk factor for the development and progression of some solid cancers, and it has been shown to stimulate pro-oncogenic signaling; its role in MM is unexplored. We evaluated the influence of OxLDL on MM cell killing by chemotherapeutics used to treat MM. OxLDL, at concentrations within the range reported for patients with metabolic syndrome, suppressed MM cell killing by the therapeutic PIs bortezomib and ixazomib. Native low-density lipoprotein (nLDL) did not affect the anti-MM effects of these PIs, which suggests that the oxidative modification of lipids or apolipoprotein in OxLDL is the mediator of cytoprotection. OxLDL did not affect MM cell killing by other agents with distinct targets such as the immunomodulatory drug lenolinamide and doxorubicin. OxLDL appeared to restore proteasome activity as evidenced by its suppression of bortezomib-induced accumulation of ubiquinated proteins and pro-apoptotic unfolded protein response signaling. The cytoprotective effects of OxLDL were suppressed when lipid hydroperoxides (LOOHs) associated with the lipoprotein were specifically reduced by pretreatment with the glutathione-dependent selenoperoxidase mimetic ebselen. Finally, immunohistochemical analysis of bone marrow biopsy samples from newly diagnosed MM patients demonstrated the presence of OxLDL in macrophages/histiocytes scattered among MM cells. Our findings suggest that OxLDL may be a potent mediator of chemoresistance to therapeutic PIs in obese/insulin-resistant MM patients. OxLDL appears to counteract the anti-MM effects of PIs through LOOH-mediated restoration of proteasome activity, which is significant since LDL is the major carrier of LOOHs in the plasma. Our findings raise the potential benefit of LDL cholesterol-lowering therapy, or pharmacologic targeting of intracellular pathways used by OxLDL, to increase the efficacy of therapeutic PIs and improve the survival of obese/insulin-resistant MM patients. Citation Format: Edward A. Medina, Javier Esparza, Srikanth Polusani, Valerie Cortez, Huynh N. Nguyen, Gopalrao V. Velagaleti, Hongxin Fan Fan, Marsha C. Kinney, Reto Asmis. Oxidized low-density lipoprotein is a potentially potent mediator of proteasome inhibitor resistance in multiple myeloma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4902.

Effect of short-chain aldehydes on the enzymatic activity of pyruvate kinase

The oxidative modification of lipids containing polyunsaturated fatty acids results in a great diversity of reactive products including short-chain aldehydes, which can covalently modify proteins. The cellular effects of some of these oxidative post-translational modifications are yet to be understood, so there is a need to study the effect of small reactive aldehydes on the activity of enzymes. The model proteins lysozyme and human serum albumin were used to map aldehyde modifications by mass spectrometry (MS). The same approach was used to treat pyruvate kinase (PK), an enzyme that catalyses the last step in glycolysis and regulates tumour growth. PK was treated for 10 mins with varying concentrations of acrolein, malondialdehyde and 4-hydroxy-2-hexenal, before assaying the enzymatic activity. In each case, a dose-dependent effect on the activity was observed. Additionally, analysis of tryptic digests of modified PK by LC-MS/MS allowed these modifications to be identified and located. Inhibition of PK has been found to be associated with cancer progression, and this study suggests that reactive short-chain aldehydes could contribute to this and influence cell survival, as well as providing novel information on the structure-function relationship of lipoxidation.

Oxidant-specific biomarkers of oxidative stress. Association with atherosclerosis and implication for antioxidant effects.

The unregulated oxidative modification of lipids, proteins, and nucleic acids induced by multiple oxidants has been implicated in the pathogenesis of many diseases. Antioxidants with diverse functions exert their roles either directly or indirectly in the physiological defense network to inhibit such deleterious oxidative modification of biological molecules and resulting damage. The efficacy of antioxidants depends on the nature of oxidants. Therefore, it is important to identify the oxidants which are responsible for modification of biological molecules. Some oxidation products produced selectively by specific oxidant enable to identify the responsible oxidants, while other products are produced by several oxidants similarly. In this review article, several oxidant-specific products produced selectively by peroxyl radicals, peroxynitrite, hypochlorous acid, lipoxygenase, and singlet oxygen were summarized and their potential role as biomarker is discussed. It is shown that the levels of specific oxidation products including hydroxylinoleate isomers, nitrated and chlorinated products, and oxysterols produced by the above-mentioned oxidants are elevated in the human atherosclerotic lesions, suggesting that all these oxidants may contribute to the development of atherosclerosis. Further, it was shown that the reactivities of physiological antioxidants toward the above-mentioned oxidants vary extensively, suggesting that multiple antioxidants effective against these different oxidants are required, since no single antioxidant alone can cope with these multiple oxidants.

Effects of oxidized lipids and lipoproteins on cardiac function.

Oxidative modifications of lipids and lipoproteins have long been linked to the pathogenesis of cardiovascular diseases including atherosclerosis and coronary disease. Furthermore, overwhelming evidence indicate that oxidized lipids are also associated with myocardial dysfunction and cardiomyopathy. Oxidized lipid derivatives are generated by enzymatic and non-enzymatic reactions with unsaturated lipids in the cell and foods. In addition, blood LDL particles are prone to oxidation leading to the formation of oxidized LDL (oxLDL), which is often associated with obesity, diabetes and metabolic disease. Whether produced endogenously or delivered by the diet, oxidized lipid derivatives induce multiple metabolic and functional disturbances in the cell leading eventually to cell injury and death. As obesity is already associated with increased oxidative stress and excess lipid deposition in the heart, the cytotoxic effects of oxidized lipids in cardiomyocytes are more pronounced in obese subjects. The overall objective of this review is to provide a synthesis of recent findings about the effects oxidized lipids in the heart. First, the origin of oxidized lipids and lipoproteins is reported. Then, the effects of oxidized lipids in cardiomyocytes are reviewed and discussed. Finally, potential preventive interventions are highlighted and discussed.

интенсивность свободнорадикальных процессов крови крыс при глубокой гипотермии и в ходе самосогревания

Hypothermic conditions of homoisothermic organisms are characterized by the activation of free-radical processes in tissues. The intensity of these processes occurring at hypothermia is less well understood. The essential increase in heart rate, breathing, blood flow velocity, and metabolic processes during warming must stimulate the generation of reactive oxygen species and oxidative modification of biomolecules. We study the levels of peroxidation markers of lipids (by malondialdehyde) and proteins (by carbonyl groups) in blood plasma and erythrocytes as well as the activity of erythrocyte antioxidant enzymes of rats after deep hypothermia (the temperature in the rectum was 20°C) and self-warming dynamics. A maximum warming rate (0.016°С/min) was revealed over the body temperature range of 22–33°С, below and above these temperatures a warming rate was essentially lower. The warming of rats resulted in a total protein content reduction which negatively correlates (r = –0.967; р<0.05) with a middle molecular peptide level. The deep hypothermia decreased the intensity of oxidative modification of lipid and proteins in blood plasma and red blood cell membranes, and the activity of red blood cell superoxide dismutase (SOD). Maximum amount of products of oxidative modification of lipids and proteins in plasma and erythrocytes membranes caused by rats’ self-warming was observed at body temperature of 30–35°С. After a complete rats’ warming the intensity of oxidative modification of lipids and proteins in plasma and erythrocyte membranes decreased. The activity of SOD and catalase of erythrocyte substantially increased when body temperature reached 35°С. The obtained data indicate that during self-warming at the body temperature of 30–35°С the oxidative stress appears in blood which requires the use of antioxidant defense.

ВПЛИВ ПРОДУКТІВ ОКИСНЕННЯ ЕСТЕРІВ ХОЛЕСТЕРОЛУ НА РОЗВИТОК АТЕРОСКЛЕРОЗУ

Products of per oxide lipid oxidation are produced in the place of increased oxidative stress and their accumulation leads to aterotic damage. Most of the investigations are still devoted to formation and oxidized lipid metabolism, but the data on their biological activity and possible pathophysiological functions are not many. In this review it was done an attempt to analyze the mechanisms of formation, metabolic activity and by transforming the cholesterol ester, which contain the unsaturated fatty acids, that may oxidize to form peroxides. The last are able to be restored to appropriate alcohols, which can be oxidized to biologically active aldehydes, which make a significant contribution to the development of progressive atherosclerotic lesions.The most cholesterol esters are as a part of ß – lipoproteins, localized in the hydrophobic core and in doing so are able to be oxidized hydro peroxides faster than the outer layer of phospholipids. Most of aldehydes, which are formed at per ester oxidation – these are nine–, eight– and five carbon compounds. Because of cholesterol esters in ß – lipoprotein were formed mainly by linoleic acid, therefore its level was reliable test of per oxidation degree of these esters.The analysis of stereoisomers of oxidized lipids, which were marked from atherogenic plaques, witnessed a significant contribution of the enzyme lipooxi genesis in oxidative modification of cholesterol esters. Selenium containing enzymes play an important role in the metabolism of cholesterol hydroxides esters, in particular: glutathionereductase and tioredoxinereductase. It was also obtained the convincing data on the participation of aldosereductase in these processes.Esther of cholesterol inhibit the mitotic activity of growth factor of atherogenic plaques, fibroblast growth factor and the ß1– antiproliferative activity of transforming growth factor.Hence, oxidative modification of lipids in general, oxidized of cholesterol esters and in particular, is one of the causes of progressive development of atherosclerotic damages, Although metabolic pathway of lipoprotein particles to the atherosclerotic plaque is search enough.

PP15 - Interplay between lipid and protein carbonylation in a cardiomyocyte model of nitrosative stress

Carbonylation of biomolecules, a stable oxidative modification yielding reactive carbonyl groups, is a well-accepted biomarker of oxidative damage, which has been linked to several oxidative stress (OS) related human diseases. Protein carbonylation can be induced via several independent mechanisms, including direct oxidation of amino acid residues or modification of nucleophilic residues with products of lipid and carbohydrate oxidation. Lipid-protein adducts are believed to be a major source of protein-bound carbonyls. Lipid peroxidation products (LPP) containing reactive carbonyls can modify proteins in two different ways via - (i) Schiff base formation with a loss of the carbonyl function or (ii) Michael addition resulting in protein carbonylation. Although oxidative modifications of lipids and proteins in biological systems are closely interconnected, they are rarely studied together. Here we combined a mass spectrometry (MS) based analysis of OS-derived LPP with proteomics targeting modified proteins for high-throughput identification of lipid-protein adducts in a dynamic cellular model of OS. The influence of nitrosative stress on carbonylation of proteins and lipids was investigated in primary cardiomyocytes treated with SIN-1 for different time intervals. Twenty-five carbonylated lipids were identified by LC-MS and considered as possibly modifying agents yielding the corresponding LPP-modified proteins. A combination of different proteomics techniques allowed identifying over 200 of these modified proteins. Systems biology analysis of modified proteins revealed alterations in Ca2+ -signalling pathways. Ca2+ mobilization was studied by activating voltage-dependent Ca2+ channels, ryanodine receptor 2 and inositol-trisphosphate receptor. Significant alterations in the activity of LPP-modified Ca2+ -channels were observed after 70 min of SIN-1 treatment. Thus, the combination of lipidomics, proteomics, and biochemical assays allowed connecting the molecular pattern of “carbonylation stress” to functional changes in the studied nitrosative stress cell model.

ВПЛИВ ІНФУЗІЙНИХ РОЗЧИНІВ ЛАКТОПРОТЕЇНУ З СОРБІТОЛОМ ТА HAESLX- 5% НА БІОХІМІЧНІ МАРКЕРИ ФІБРОГЕНЕЗУ ЛЕГЕНЕВОЇ ТКАНИНИ В ЩУРІВ З ОПІКОВОЮ ТРАВМОЮ ШКІРИ

<p><strong>INFLUENCE </strong><strong>of</strong><strong> </strong><strong>laktoprotein</strong><strong>um</strong><strong> with sorbitol and HAES-LX-5% infusion</strong><strong>’S</strong><strong> solutions </strong><strong>on</strong><strong> biochemical markers of fibrogenesis lung tissue in rats with </strong><strong>skin</strong><strong> burn trauma </strong><strong></strong></p><p><strong>Ocheretnyuk</strong><strong> </strong><strong>A</strong><strong>.А. </strong><strong></strong></p><p>VinnytsiaNationalMedicalUniversityby M.I. Pyrogov <strong></strong></p><p><strong>Summary. </strong>It is shown that in a case of burn disease, especially on day 3, remodeling of connective tissue and oxidative damage phospholipid lungs takes place. Infusion of colloidal hyperosmolar solution - HAES-LX- 5% and lactoproteinum solution with sorbitol equally causes antifibrogenic effect and reduces the severity of oxidative degradation of membrane phospholipids in rats with skin burns. Their protective effect is the most expressive on day 7 of the experiment.</p><p><strong>Keywords:</strong> infusion therapy, fibrogenesis, phospholipids, HAES-LX-5%, lactoproteinum with sorbitol.</p><p><strong>Introduction.</strong><strong></strong></p><p>Trigger mechanisms for alteration of lung tissue under conditions of skin burn injuries is considered a development of oxidative stress accompanied by accumulation of oxidative modification of lipids and destruction of cell membranes. This process is characterized also by remodeling of connective tissue and activation of fibrogenesis processes in the lung tissues. It is quite clear that the efficacy of potential correctors of the lung functional condition is largely determined by their ability to contain the accumulation of reactive free radicals, reduce lesion of bi-lipidic layer of cell membranes, and to detect depressing effect on fibrogenesis in the lung tissue.<strong></strong></p><p class="-1"><strong>Methods.</strong></p><p class="-1">The contents of biochemical studies: serum samples were tested for markers of degradation of connective tissue and fibrogenesis (free oxyproline, transforming growth factor-β1), lung homogenate was tested for contents of phosphatidylcholine and <a href="http://www.multitran.ru/c/m.exe?t=5341349_1_2&s1=%EB%E8%E7%EE%F4%EE%F1%F4%E0%F2%E8%E4%E8%EB%F5%EE%EB%E8%ED">lysophosphatidylcholine</a>.</p><p><strong>Results and discussion.</strong></p><p class="-1">Skin burn injury causes diverse biochemical and pathophysiological changes in rats in whole and particularly in the lung tissue. Our research has shown that burn disease is accompanied by distortion of phospholipid spectrum of lung tissue, which manifested by decrease of phosphatidylcholine content and increase of its oxidation product - <a href="http://www.multitran.ru/c/m.exe?t=5341349_1_2&s1=%EB%E8%E7%EE%F4%EE%F1%F4%E0%F2%E8%E4%E8%EB%F5%EE%EB%E8%ED">lysophosphatidylcholine</a>. Covalent modification of phospholipid membranes in case of burn disease leads to disruption of the permeability of cell membranes and disorders in the cellular pumps required to transport materials and create ion concentration gradient on both sides of cell membrane. Along with these changes, the burn disease is characterized by connective tissue remodeling and fibrogenesis processes activation, as convincingly proved by growth in serum free oxyproline and transforming growth factor TGF-β1. Pharmacological correction of burn disease using HAES-LX-5% and lactoproteinum with sorbitol solutions somewhat normalized ratio of phosphatidylcholine/<a href="http://www.multitran.ru/c/m.exe?t=5341349_1_2&s1=%EB%E8%E7%EE%F4%EE%F1%F4%E0%F2%E8%E4%E8%EB%F5%EE%EB%E8%ED">lysophosphatidylcholine</a> in cell membranes of the lung tissue and prevented remodeling of connective tissue and fibrogenesis activation. HAES -LX-5% was proven at least not inferior versus a reference medicine - lactoproteinum with sorbitol- in terms of the above-said effects.</p><p><strong>Conclusions.</strong></p><p class="-1">Skin burn injury in rats accompanied by the development of lung imbalance of lung phospholipids (phosphatidylcholine content reduced by 35-47% and the <a href="http://www.multitran.ru/c/m.exe?t=5341349_1_2&s1=%EB%E8%E7%EE%F4%EE%F1%F4%E0%F2%E8%E4%E8%EB%F5%EE%EB%E8%ED">lysophosphatidylcholine</a> grew by 34-66%) and increasing content of connective tissue destruction (free oxyproline - by 60-97%) and fibrogenesis (TGF-β1 – by 58-137%) markers in serum.</p><p class="-1">Administration of colloidal-osmotic solution HAES-LX-5% and lactoproteinum with sorbitol suppressed development of connective tissue remodeling processes of fibrogenesis and oxidative lesion of lungs phosphorlipidic bilayer.</p>

Photo-protective effect of americanin B against ultraviolet B-induced damage in cultured human keratinocytes

Excessive ultraviolet (UV) radiation, a constituent of sunlight, can induce multiple types of skin damage. We recently demonstrated that americanin B, a lignin compound, protected cells against hydrogen peroxide (H2O2)-induced damage by exerting antioxidant effects and inhibiting apoptosis. In this study, we investigated the ability of americanin B to protect against cell injury induced by UVB (280–320nm), the most harmful UV wavelengths, in human HaCaT keratinocytes. Americanin B absorbed UVB, eliminated UVB-induced intracellular reactive oxygen species (ROS), and decreased the extent of UVB-induced oxidative modification of lipids, proteins, and DNA. In addition, americanin B inhibited UVB-induced apoptosis, as indicated by reductions in apoptotic body formation and DNA fragmentation. Furthermore, americanin B reversed the depolarization of the mitochondrial membrane induced by UVB exposure. These protective activities were associated with down-regulation of apoptosis-promoting proteins, Bax, caspase-9, and caspase-3 and up-regulation of an apoptosis inhibitor, Bcl-2. These results suggest that americanin B can protect human keratinocytes against UVB-induced cell damage.

Toxicological study and oxidative stress evaluation for safety assessment of xylanase preparations in Wistar rats.

Acute and 90-day subchronic oral toxicity studies were conducted to establish the safety evaluation of xylanases preparations. A potential oxidative stress evaluation was also performed through testing the generation of oxidative radicals, depletion of antioxidants via oxidative modification of lipids, proteins and DNA of organ cells. During the subchronic oral toxicity study, no mortality was observed, obvious treatment-related clinical signs and urinalysis parameters were in normal range. Differences in some hematological parameters, biochemistry, relative organ weight, and histopathology examinations between the treated group and the control group were not judged to be adverse. Our results indicated that the no-observed-adverse-effect level for xylanases was 1,500TXU/kg/day and the plasma antioxidant assays showed that these xylanases did not produce free-radicals nor oxidative injuries. On the basis of the bacterial reverse mutation assay data, it is concluded that the expressed xylanase in Pichia pastoris do not present any mutagenic potential when tested in relevant genotoxicological assays.

Інтенсивність окисних процесів у мікросомній фракції печінки щурів за умов різного забезпечення поліненасиченими жирними кислотами

The effect of fat compositions with the varying ratio of polyunsaturated fatty acids (PUFAs) of families ω-3 and ω-6 on oxidation process intensity in microsomal fraction of rat liver has been investigated. The aim of the study was to investigate the level of markers of oxidative modification of lipids and proteins in microsomal fraction of rat liver. Fat components in the experiment diets were presented by sunflower oil, soybean oil and fish oil. Rats were fed using one of the fillowing 5 diets for the period of 4 weeks: 1) AIN-93 diet with 7% sunflower oil and fish oil, with the inclusion of linoleic acid, eicosapentaenoic acid and docosahexaenoic acid in the ratio of ω-6:ω-3 – 7:1 (control diet); 2) AIN-93 diet with 7% soybean oil, with the inclusion of linoleic acid and α-linolenic acid in the ratio of 7:1; 3) the diet containing only ω-6 PUFAs; 4) the diet containing only ω-3 PUFAs; 5) the diet without PUFAs. The fatty acid compositions of the diets were analysed by gas chromatography. We measured the primary and secondary lipoperoxidation products, proteins carbonyl derivatives and SH-groups of proteins. It was shown that inclusion of linoleic acid and α-linolenic acid in the ratio of 7:1 or ω-6 PUFAs into the animal diet increased lipid peroxidation in microsomal fraction of the rat liver as compared with the control group. Only ω-6 PUFAs increased the oxidative modification of proteins in microsomal fraction of the rat liver as compared with the control rat group. High dose of ω-3 PUFAs – eicosapentaenoic acid and docosahexaenoic acid had no influence on free radical oxidation of lipids and proteins. Using the diet without PUFAs increased oxidation process intensity in microsomal fraction of rat liver. According to our study, ω-6 PUFAs increased the oxidative modification of lipids and proteins in microsomal fraction of the rat liver. ω-3 PUFAs, in particular, eicosapentaenoic acid and docosahexaenoic acid, increased lipid and protein resistance to oxidative modification in microsomal fraction of the rat liver.

Correlation of serum paraoxonase activities in known cases of 130 elderly hypertensive South Asian aged 56–64 years – a hospital based study

ObjectiveTo evaluate paraoxonase activity, antioxidant status and lipid peroxidation in hypertensive participants and to address the hypothesis that oxidative modifications of lipids due to hypertension can cause changes in serum paraoxonase activities. MethodsThe serum paraoxonase activities, antioxidants and lipid peroxidation were determined in 130 hypertensive participants and 130 age-sexes matched normotensive healthy volunteers served as control. Serum paraoxonase activities were measured by enzymatic kit. The glutathione peroxidase, superoxide dismutase and catalase activity were determined by standard methods. Malondialdehyde was measured by thiobarbituric acid reaction. Conjugated diene level was measured by Recknagel and Glende method. Serum uric acid, total bilirubin, serum albumin, serum ascorbic acid and lipid profile were analyzed by standard methods. ResultsTotal cholesterol, triglycerides, low-density lipoprotein cholesterol were significantly higher and high-density lipoprotein cholesterol were significantly lower in hypertensive patients when compared to normotensive healthy controls. The superoxide dismutase, glutathione peroxidase and catalase were significantly lower in hypertensive when compared with normotensive. Similar findings were observed in the levels of albumin, uric acid, bilirubin and ascorbic acid when hypertensives were compared with normotensive. The oxidative stress indicators namely malondialdehyde and conjugated diene were significantly higher and paraoxonase activity were significantly lower in hypertensive. ConclusionsOur study concludes that paraoxonase activities are bound to alter in hypertension which is caused due to interplay of several confounding factors namely oxidative stress, increased oxidized low-density lipoprotein and depletion of antioxidants.

Suppressive effects of Hydroxytyrosol on oxidative stress in erythrocytes

We investigated the oxidative modifications of lipids, proteins and antioxidants enzymes activities, in erythrocytes treated with H2O2 in the presence or absence of hydroxytyrosol (HT) at 37°C for 30 min. Conjugated dienes level was measured as biomarker of lipid peroxidation. Protein carbonyl level was measured as biomarker of protein oxidation. The antioxidants enzymes activities were evaluated by superoxide dismutase and catalase activities determinations. Conjugated dienes levels decreased in erythrocytes after hydroxytyrosol treatment as compared to erythrocytes treated with 0.2 mM H2O2. Protein carbonyl levels increased in erythrocytes after hydroxytyrosol treatment as compared to erythrocytes treated with 0.2 mM H2O2. In addition, this study showed a prospective protective action of HT of human erythrocytes from the attack of reactive oxygen species. In fact, a considerable increase of superoxide dismutase activity by 40% was showed after incubation of erythrocytes with HT at dose 5 µg/ml. Although, there were no significant differences in catalase activity in erythrocytes after hydroxytyrosol treatment as compared to erythrocytes treated with 0.2 mM H2O2. This study demonstrates that hydroxytyrosol prevents protein oxidation and lipid peroxidation caused by H2O2 treatment using erythrocytes cell model. Key words: Hydroxytyrosol, thiol, erythrocytes, conjugated dienes, malondialdehyde, superoxide dismutase, catalase, peripheral blood mononuclear (PBL), peripheral blood mononuclear.

Mass spectrometry and inflammation—MS methods to study oxidation and enzyme-induced changes of phospholipids

Many diseases such as arthritis or atherosclerosis are accompanied by inflammatory processes. Inflammation is characterized by the infiltration of cells such as neutrophilic granulocytes and (a) the release of phospholipases [particularly phospholipase A2 (PLA2)] and (b) the generation of reactive oxygen as well as nitrogen species (ROS and RNS). While PLA2 leads to defined lyso products (lacking one acyl residue), lipid oxidation is characterized by much more complex product patterns, including lipid peroxides, aldehydes (by double bond cleavage), and many others. Nevertheless, oxidation processes are highly important under in vivo conditions because molecules with regulatory functions are generated by the oxidation of lipids and/or free fatty acids. Therefore, lipid oxidation products as well as lysolipids are increasingly assumed to represent important disease (bio)markers. Consequently, there is also increasing interest in methods to characterize these products qualitatively and quantitatively.Mass spectrometry (MS) seems to be the method of choice to study (phospho)lipids changed under inflammatory conditions: nowadays, soft ionization MS methods are regularly used to study oxidative lipid modifications because of their high sensitivities and the tremendous mass resolutions that are achievable by using modern mass spectrometers. However, experimental care is required to be able to detect all relevant products. Although electrospray ionization (ESI) MS is so far most popular, applications of matrix-assisted laser desorption and ionization (MALDI) MS are continuously increasing. This review aims to summarize the so far available data on MS analyses of oxidized lipids as well as lysolipids. In addition to model systems, special attention will be paid to the monitoring of oxidized lipids and lysolipids under in vivo conditions. It is the aim of this review to provide a critical survey of the advantages and drawbacks of the different MS methods, with the focus on MALDI and ESI.

СВЯЗЬ КОЛОСТРАЛЬНОГО ИММУНИТЕТА И БИОХИМИЧЕСКОГО СТАТУСА У НОВОРОЖДЕННЫХ ТЕЛЯТ В ПЕРВЫЕ ДНИ ЖИЗНИ

It is known that in animals with a desmohorial placenta, the unchanged colostral immunoglobulins enter the blood from the digestive tract for the first two days after birth, but remain the most active during the first hours of life. The passive transport of these immunoglobulins is influenced by various factors, including breed traits, housing conditions, and terms, amount and quality of colostrum intake. However, information about the effect of metabolic and antioxidant status of calves on the formation of colostral immunity is not complete until now. We studied the relationship between colostral immunity and biochemical status of newborn Red-and-White breed calves. The results of our investigations conclusively prove that the high level of magnesium and low values of calcium-magnesium ratio in the calves’serum lead to disruption of neuromuscular conduction and decrease muscle tone which are manifested through the later appearance and weakness of sucking reflex in animals. As a result, the volume of maternal colostrum is insufficient for the calves. The long-lasting (more than 48 hours) hypoxia and acidosis, and the increased toxic lipid peroxidation in neonatal calves cause a colostral immunoglobulin transport disorder. Protein and lipid oxidative modifications destruct the antibodies, circulating in newborn calves, and suppress the colostral immunity. In spite of the high level of humoral antibodies to bovine parainfluenza-3 and infectious bovine rhinotracheitis viruses antigens in cow-mothers, not all newborn calves are able to obtain the necessary colostral protection, as it is greatly affected by their metabolic and antioxidant status.

The Effects of Fasciola hepatica Infection on the Total Antioxidant Status (TAS) and the Activity of Proteases and Their Inhibitors in Rat Serum

Fasciola hepatica infection results in increased production of reactive oxygen species (ROS) and changes the activity/level of antioxidants in the host organism, which leads to oxidative stress formation and oxidative modifications of lipids and proteins. Taking this into account, the aim of this study was to assess the antioxidant potential and the activity of proteases and their inhibitors in the serum of rats infected with F. hepatica. Wistar rats were infected per os with 30 metacercariae of F. hepatica. The total antioxidant status (TAS) and the activity of cathepsin G and elastase and their inhibitors (alpha1-antitrypsin and alpha2-macroglobulin) were determined at 4, 7, and 10 weeks post infection (wpi). It was confirmed that F. hepatica infection leads to a decrease in the antioxidant capacity of serum, which was manifested as a reduction in total antioxidant status by about 24, 39, and 27%, respectively, at 4, 7, and 10 wpi. At the same time, the activity of proteases increased significantly: cathepsin G by about 25, 37, and 30%, and elastase by about 18, 16, and 9% during the course of F. hepatica infection, compared with the control group. However, the activity of alpha1-antitrypsin was significantly reduced, by 36, 55, and 25%, while alpha2-macroglobulin activity was reduced by about 14, 17, and 8% during the same period of fasciolosis. These results indicate that the shift in protease/antiprotease balance towards protease action observed during the course of fasciolosis may result in a decrease in host antioxidant capacity.

Oxidized phosphatidylcholines in membrane‐level cellular signaling: from biophysics to physiology and molecular pathology

The oxidation of lipids has been shown to impact virtually all cellular processes. The paradigm has been that this involvement is due to interference with the functions of membrane-associated proteins. It is only recently that methodological advances in molecular-level detection and identification have begun to provide insights into oxidative lipid modification and its involvement in cell signaling as well as in major diseases and inflammation. Extensive evidence suggests a correlation between lipid peroxidation and degenerative neurological diseases such as Parkinson's and Alzheimer's, as well as type 2 diabetes and cancer. Despite the obvious relevance of understanding the molecular basis of the above ailments, the exact modes of action of oxidized lipids have remained elusive. In this minireview, we summarize recent findings on the biophysical characteristics of biomembranes following oxidative derivatization of their lipids, and how these altered properties are involved in both physiological processes and major pathological conditions. Lipid-bearing, oxidatively truncated and functionalized acyl chains are known to modify membrane bulk physical properties, such as thermal phase behavior, bilayer thickness, hydration and polarity profiles, as manifest in the altered structural dynamics of lipid bilayers, leading to augmented membrane permeability, fast lipid transbilayer diffusion (flip-flop), loss of lipid asymmetry (scrambling) and phase segregation (the formation of 'rafts'). These changes, together with the generated reactive lipid derivatives, can be further expected to interfere with lipid-protein interactions, influencing metabolic pathways, causing inflammation, the execution phase in apoptosis and initiating pathological processes.