Secondary Products Of Lipid Peroxidation Research Articles

Plant acclimation to ionising radiation requires activation of a detoxification pathway against carbonyl-containing lipid oxidation products.

Ionising γ radiation produces reactive oxygen species by water radiolysis, providing an interesting model approach for studying oxidative stress in plants. Three-week old plants of Arabidopsis thaliana were exposed to a low dose rate (25 mGy h-1) of γ radiation for up to 21 days. This treatment had no effect on plant growth and morphology, but it induced chronic oxidation of lipids which was associated with an accumulation of reactive carbonyl species (RCS). However, contrary to lipid peroxidation, lipid RCS accumulation was transient only, being maximal after 1 day of irradiation and decreasing back to the initial level during the subsequent days of continuous irradiation. This indicates the induction of a carbonyl-metabolising process during chronic ionising radiation. Accordingly, the γ-radiation treatment induced the expression of xenobiotic detoxification-related genes (AER, SDR1, SDR3, ALDH4, and ANAC102). The transcriptomic response of some of those genes (AER, SDR1, and ANAC102) was deregulated in the tga256 mutant affected in three TGAII transcription factors, leading to enhanced and/or prolonged accumulation of RCS and to a marked inhibition of plant growth during irradiation compared to the wild type. These results show that Arabidopsis is able to acclimate to chronic oxidative stress and that this phenomenon requires activation of a carbonyl detoxification mechanism controlled by TGAII. This acclimation did not occur when plants were exposed to an acute γ radiation stress (100 Gy) which led to persistent accumulation of RCS and marked inhibition of plant growth. This study shows the role of secondary products of lipid peroxidation in the detrimental effects of reactive oxygen species.

Long-term consequences of acute toxic prenatal hypoxia induced by sodium nitrite in rat experiments

Introduction. Gestational hypoxia plays an important role in fetal development, as it causes the development of oxidative stress and delayed psychomotor development. The aim of the study was to evaluate the prenatal effect of sodium nitrite on indices characterizing orienting and exploratory activity, mental activity and the degree of hypoxia in rat offspring. Materials and methods. Acute hypoxia was modeled by administration of sodium nitrite at a dose of 30 mg/kg intramuscularly to five pregnant rats during 16–19 days of gestation. Five females constituted a control group. In 50 born rats, orientation and exploration activity, cognitive functions, intensity of lipid peroxidation and glycolysis were studied. Results. The offspring of females that underwent acute hypoxia significantly lagged behind in the positive dynamics of body weight gain compared to control individuals. Thirty-day-old rats showed a pronounced disorder of the structure of behavioral pattern, learning process and long-term memory, increased content of diene conjugates, malonic dialdehyde and the level of lactate dehydrogenase activity in blood. Discussion. It was found that offspring whose mothers suffered acute hypoxia of toxic genesis developed pronounced behavioral disorders of psychomotor agitation and cognitive dysfunction characterized by decreased learning ability and impaired long-term memory. The content of primary and secondary products of lipid peroxidation and lactate dehydrogenase was increased in rats. The development of cellular oxidative stress under conditions of intrauterine hypoxia leads to oxygen deficiency in the fetus and a switch from tissue respiration to glycolysis, which underlies CNS damage. Conclusion. It was shown that sodium nitrite administration during the period from the 16th to the 19th day of gestation caused hyperactivity, depressed emotional status, and decreased orienting and exploratory activity and the ability to learn and retain a memory trace in rat offspring. Increased levels of diene conjugates and malonic dialdehyde, lactate dehydrogenase activity were observed in rats.

Oxidative modification of collagen by malondialdehyde in porcine skin

Human skin is exposed to various physical and chemical stress factors, which commonly cause the oxidation of lipids and proteins. In this study, azo initiator AAPH [2,2′ -azobis(2-methylpropionamidine) dihydrochloride] was employed to initiate lipid peroxidation in porcine skin as an ex vivo model for human skin. We demonstrate that malondialdehyde (MDA), a secondary product of lipid peroxidation, is covalently bound to collagen in the dermis, forming MDA-collagen adducts. The binding of MDA to collagen results in an unfolding of the collagen triple helix, formation of the dimer of α-chains of collagen, and fragmentation of the collagen α-chain. It is proposed here that the MDA is bound to the lysine residues of α-chain collagen, which are involved in electrostatic interaction and hydrogen bonding with the glutamate and aspartate of other α-chains of the triple helix. Our data provide crucial information about the MDA binding topology in the skin, which is necessary to understand better the various types of skin-related diseases and the aging process in the skin under stress.

Formation of free acetaldehydes derived from lipid peroxidation in U937 monocyte-like cells

Acetaldehyde can be found in human cells as a byproduct of various metabolic pathways, including oxidative processes such as lipid peroxidation. This secondary product of lipid peroxidation plays a role in various pathological processes, leading to various types of civilization diseases. In this study, the formation of free acetaldehyde induced by oxygen-centred radicals was studied in monocyte-like cell line U937. Exposure of U937 cells to peroxyl/alkoxyl radicals induced by azocompound resulted in the formation of free acetaldehyde. Acetaldehyde is formed by the cleavage of fatty acids, which represents the breakdown of fatty acids into smaller fragments initiated by the cyclization of lipid peroxyl radical and β-scission of lipid alkoxyl radical. The cleavage of fatty acids alters the integrity of the plasma and nuclear membrane, leading to the loss of cell viability. Understanding the pathological processes of acetaldehyde formation is an active area of research with potential implications for preventing and treating various diseases associated with oxidative stress.

Вплив aктовегіну на механізми розвитку окисного стресу у хворих на цукровий діабет 2-го типу з кардіоваскулярною автономною нейропатією

The effects of actovegin on the mechanisms of oxidative stress (OS) developing in the blood of patients with type 2 diabetes mellitus (DM2) and cardiovascular autonomic neuropathy (CVAN) were investigated. The aim of the study was to establish the effectiveness of treatment with actovegin for the pro- and antioxidant balance impairment and changes in gene expression of HIF-1α and mTOR in the blood of patients with DM2 and CVAN. It was shown that intravenous injections of actovegin at a dose of 1000 mg per day for 10 days and further prolonged oral administration of this drug at a dose of 800 mg per day for 90 days led to a decrease in the content of secondary products of lipid peroxidation in blood plasma and H2O2 production in erythrocytes of patients with DM2 and CVAN. These changes were indicative of a weakening of OS intensity. It was also shown that treatment with actovegin promoted an increase in total plasma SOD activity as well as reduced glutathione and glutathione peroxidase activity in erythrocytes from patients. Treatment with actovegin also raised the gene expression of HIF-1α and reduced the gene expression of mTOR in leukocytes of patients with DM2 and CVAN. These genetic changes may serve as a protective mechanism against the development of OS, which acts through different metabolic pathways. So, actovegin administration counteracting OS development due to the impact on the different components of pro- and antioxidant system as well as on HIF-1α and mTOR genes expression may offer new clinical avenues for pharmacological treatment of patients with DM2 and CVAN.

Innovative Solutions for Food Analysis: Microextraction Techniques in Lipid Peroxidation Product Detection

Lipid peroxidation, the most aggressive reaction in food, results in the formation of reactive organic compounds that detrimentally impact food sensory qualities and consumers’ health. While controlled lipid peroxidation can enhance flavors and appearance in certain foods, secondary peroxidation products lead to sensory deterioration in a variety of products, such as oils, alcoholic beverages, and meat. This publication reviews the use of modern analytical techniques for detecting and quantifying carbonyl compounds, i.e., secondary lipid peroxidation products. The paper focuses specifically on microextraction-based methods: dispersive liquid-liquid microextraction (DLLME), solid-phase microextraction (SPME), and gas-diffusion microextraction (GDME). These techniques offer efficient and sensitive approaches to extracting and quantifying lipid oxidation products and contribute to the understanding of oxidative deterioration in various food products. The review outlines recent advancements, challenges, and limitations in these microextraction techniques, as well as emphasizes the potential for further innovation and improvement in the field of food analysis.

Malondialdehyde enhances PsbP protein release during heat stress in Arabidopsis

Under environmental conditions, plants are exposed to various abiotic and biotic stress factors, which commonly cause the oxidation of lipids and proteins. Lipid peroxidation constantly produces malondialdehyde (MDA), a secondary product of lipid peroxidation, which is covalently bound to proteins forming MDA-protein adducts. The spatial distribution of MDA-protein adducts in Arabidopsis leaves shows that MDA-protein adducts are located in the chloroplasts, uniformly spread out over the thylakoid membrane. At the lumenal side of thylakoid membrane, MDA interacts with PsbP, an extrinsic subunit of the photosystem II (PSII), which is in electrostatic interaction with the PSII core proteins. Under heat stress, when MDA is moderately enhanced, the electrostatic interaction between PsbP and PSII core proteins is weakened, and PsbP with bound MDA is released in the lumen. It is proposed here that the electrophilic MDA is bound to the nucleophilic lysine residues of PsbP, which are involved in electrostatic interactions with the negatively charged glutamate of the PSII core protein. Our data provide crucial information about the MDA binding topology in the higher plant PSII complex, which is necessary to understand better the physiological functions of MDA for plant survival under stress.

Assessment of Antioxidant Stability of Meat Pâté with Allium cepa Husk Extract.

Antioxidants play a very important role in the food industry. Recently, both science and industry have shown substantial preference for natural antioxidants, including searching for antioxidant substances from natural sources without undesirable side effects. The purpose of this study was to evaluate the effect of adding Allium cepa husk extract at a volume of 68 or 34 μL/g of unsalted blanched materials to replace 34% and 17% of the beef broth, respectively, which corresponded to a total antioxidant capacity (TAC) of 44.4 or 22.2 μmol-equiv. Q/100 g meat pté (i.e., 13.42 or 6.71 mg of quercetin/100 g meat pté), on the quality and safety indicators of the developed meat pté. The TAC according to a ferric reducing antioxidant power assay, thiobarbituric acid reactive substances, and physicochemical and microbiological characteristics were determined during the storage of the meat pté. Proximal and UPLC-ESI-Q-TOF-MS analyses were also performed. The addition of yellow onion husk ethanolic extract to the meat pté at both volumes allowed the maintenance of an increased content of antioxidants, which contributed to a decrease in the generation of secondary products of lipid peroxidation for 14 days of storage at 4 ∘C. The results of the microbiological analyses showed that the developed meat ptés were safe according to all indicators of microbial spoilage within 10 days of production. The results supported the use of yellow onion husk extract in the food industry to contribute to improving the functionality of meat products, developing products for a healthy lifestyle, and providing clean-label foods without or with a minimal content of synthetic additives.

Effect of the complex of natural terpenes and vitamin E Renotineх® on free radical processes in patients with urolithiasis

BACKGROUND: One of the leading links in the pathogenesis of urolithiasis is oxidative stress, which occurs as a result of the intensification of free radical oxidation with insufficient activity of the antioxidant defense system of the body.
 AIM: The aim of the study was to study the effect of a complex of natural terpenes and vitamin E Renotineх on the state of oxidative stress in patients with urolithiasis in the postoperative period after percutaneous nephrolithotripsy.
 MATERIALS AND METHODS: The study included 42 patients. Of the 35 people who underwent percutaneous nephrolithotripsy, 2 groups were formed. Patients of the main group (n = 20), in contrast to the control group (n = 15), received Renotinex (Polaris LLC, Russia) before and after surgery, 2 capsules (1 capsule 300 mg) twice a day. To determine the main indicators of the activity of free-radical processes in the body, all patients underwent a blood test on the 3rd day after surgery. The total activity of the pro- and antioxidant systems in blood plasma was determined by the method of induced chemiluminescence. The activity of lipid peroxidation was assessed by determining the concentration of active products of thiobarbituric acid secondary products of lipid peroxidation in blood erythrocytes. The activity of antioxidant enzymes was studied by spectrophotometric method. To determine the ability of blood plasma to crystallize in some of the same patients with urolithiasis while taking Renotinex, the method of wedge dehydration was used. For a comparative analysis of the crystal structure of dried blood plasma samples (facies), 7 healthy volunteers were included in the study, which made up the third group (comparison group).
 RESULTS: The results of the study reliably demonstrate that the composition of the complex of natural terpenes and vitamin E Renotinex has a positive effect on free-radical processes in patients with urolithiasis, biochemical parameters of blood plasma (indicators of induced chemiluminescence, catalase activity, malondialdehyde level), as well as on crystallization processes blood plasma, which is confirmed by the method of wedge dehydration of blood plasma. Any change in the body caused by excessive activity of free-radical oxidation processes is reflected in the composition of the blood, and specifically in the indicators of the mechanical characteristics of blood plasma (viscosity, structure, surface tension), which determine the shape of the resulting structures of the drying drop of biological fluid.
 CONCLUSIONS: The complex of natural terpenes and vitamin E Renotinex has a positive effect on free-radical processes, biochemical parameters of blood plasma, as well as on the systemic structural organization of blood plasma in patients operated on for urolithiasis. The inclusion of the combined product Renotinex in the treatment regimen for patients with urolithiasis is pathogenetically justified.

Integral assessment of non-specific lipid peroxidation reactions blood in adolescent girls of the Siberian ethnos

BACKGROUND: Integral parameters, in particular, the oxidative stress coefficient are informative and can be used both for evaluation of pathological conditions and compensatory-adaptive reactions of the organism.
 AIM: To investigate an integral coefficient the activity of nonspecific reactions of lipid peroxidation in adolescent girls of the Buryat, Evenki and Tofalar ethnic groups, as compared to the non-indigenous ethnic groups, by applying.
 METHODS: Total 190 adolescent girls (Buryats, Evenki and Tofalar, and nonindigenous population (for example of Russians)) living in the Irkutsk region were the objects of research. The survey was carried out in expeditionary conditions, in the territories of compact residence of ethnic groups. To calculate the integral coefficient (oxidative stress coefficient), spectrophotometry and fluorometry methods we implemented. The individual indicators: primary, secondary, and final products of lipid peroxidation as well as antioxidant defense components were measured.
 RESULTS: According to the obtained data, a lower content of diene conjugates (DC) (p 0.0001), ketodienes and conjugated trienes (KD and СT) (p=0.0003), -tocopherol (p 0.0001) with elevated levels of TBA-active products (p=0.0074) and superoxide dismutase activity (p=0.0008) in the Buryat ethnic girls group relative to similar parameters of girls in the non-ingenious population was observed. Girls of Tofalar ethnic group had higher values of DC (p=0.0009), with reduced values of KD and CT (p=0.0044) compared to the non-indigenous population. There were no differences among girls of the Evenk ethnic group relative to Russians. An integrative analysis of the state of nonspecific lipid peroxidation reactions using the coefficient showed no significant differences between the studied groups.
 CONCLUSION: The conducted study demonstrates certain changes in the lipid peroxidationantioxidant defence system, in the absence of changes in the total indicator among girls representing Siberian ethnic groups and the Russian population living next to them, which can be the basis for subsequent monitoring of their health status.

Study of parameters of lipid peroxidation and antioxidant protection in rats treated with cadmium nitrate with biocorrection by infusion of Beta vulgaris seeds

Recently, interest in natural antioxidants and their use in the food industry has increased. In addition to ensuring maximum safety of the produced product, they also serve as an antioxidant shield for the entire living organism. Plant extracts contain flavonoid compounds that have an antioxidant effect. In this regard, the purpose of the article is to study the antioxidant properties of infusion of Beta vulgaris’s seeds, to establish the relationship between acute and subacute inoculation of rats with cadmium nitrate and oxidative stress. For this experimental study, we used 50 male rats. The animals were exposed to Cd nitrate, with an initial weight of 180 ± 30 g. The first groups of rats were injected with cadmium nitrate at a dose of 0.1 g/L inter peritoneal, the second groups received a 0.01% solution of cadmium nitrate 1 ml 5 days a week, orally for 10 and 24 days. The state of oxidative metabolism in the blood was investigated. To assess the state of oxidative metabolism in the blood, the primary, secondary and end products of lipid peroxidation were determined, such as diene conjugates (DC), cetodiene (CD), malondialdehyde (MDA), Schiff bases (SHB), and the activity of glutathione peroxidase (GP), catalase (CAT), and adenosine deaminase (ADA) enzymes were evaluated by the parameters of antioxidant protection. The mean ± SEM values were calculated for each group to determine the significance of the intergroup difference. Each parameter was analyzed separately using the one-way analysis of variance (ANOVA) test. To determine the difference between groups, Student’s “t”-test was used. Studies have shown that with the use of cadmium in the blood of experimental animals, there is a violation of catabolits of lipoperoxidation, depending on the length of the days of poisoning, but a significant decrease in the biocorrection of Beta vulgaris’s seeds. Because of in this study, we found that the activity levels of antioxidant defense enzymes were significantly increased in the blood of experimental animals, which biocorrected with beetroot seed infusion. In conclusion, our study allows us to state that the use infusion of Beta vulgaris’s seeds in subacute and acute experiments with poisoning of experimental rats with cadmium nitrate as an antioxidant protective effect.

Malondialdehyde as an Important Key Factor of Molecular Mechanisms of Vascular Wall Damage under Heart Diseases Development.

This mini review is devoted to a specific issue: the role of malondialdehyde (MDA)-a secondary product of free radical lipid peroxidation-in the molecular mechanisms of the formation of primary atherosclerotic vascular wall lesions. The principal difference between this review and the available literature is that it discusses in detail the important role in atherogenesis not of "oxidized" LDL (i.e., LDL particles containing lipohydroperoxides), but of LDL particles chemically modified by the natural low-molecular weight dicarbonyl MDA. To confirm this, we consider the data obtained by us earlier, indicating that "atherogenic" are not LDL oxidized as a result of free radical lipoperoxidation and containing lipohydroperoxy derivatives of phospholipids in the outer layer of particles, but LDL whose apoprotein B-100 has been modified due to the chemical reaction of terminal lysine residue amino groups of the apoB-100 with the aldehyde groups of the MDA (Maillard reaction). In addition, we present our original data proving that MDA injures endothelial glycocalyx that suppress the ability of the endothelium to control arterial tone according to changes in wall shear stress. In summary, this mini review for the first time exhaustively discloses the key role of MDA in atherogenesis.

C60 fullerene attenuates muscle force reduction in a rat during fatigue development

C60 fullerene (C60) as a nanocarbon particle, compatible with biological structures, capable of penetrating through cell membranes and effectively scavenging free radicals, is widely used in biomedicine. A protective effect of C60 on the biomechanics of fast (m. gastrocnemius) and slow (m. soleus) muscle contraction in rats and the pro- and antioxidant balance of muscle tissue during the development of muscle fatigue was studied compared to the same effect of the known antioxidant N-acetylcysteine (NAC). C60 and NAC were administered intraperitoneally at doses of 1 and 150 mg kg−1, respectively, daily for 5 days and 1 h before the start of the experiment. The following quantitative markers of muscle fatigue were used: the force of muscle contraction, the level of accumulation of secondary products of lipid peroxidation (TBARS) and the oxygen metabolite H2O2, the activity of first-line antioxidant defense enzymes (superoxide dismutase (SOD) and catalase (CAT)), and the condition of the glutathione system (reduced glutathione (GSH) content and the activity of the glutathione peroxidase (GPx) enzyme). The analysis of the muscle contraction force dynamics in rats against the background of induced muscle fatigue showed, that the effect of C60, 1 h after drug administration, was (15–17)% more effective on fast muscles than on slow muscles. A further slight increase in the effect of C60 was revealed after 2 h of drug injection, (7–9)% in the case of m. gastrocnemius and (5–6)% in the case of m. soleus. An increase in the effect of using C60 occurred within 4 days (the difference between 4 and 5 days did not exceed (3–5)%) and exceeded the effect of NAC by (32–34)%. The analysis of biochemical parameters in rat muscle tissues showed that long-term application of C60 contributed to their decrease by (10–30)% and (5–20)% in fast and slow muscles, respectively, on the 5th day of the experiment. At the same time, the protective effect of C60 was higher compared to NAC by (28–44)%. The obtained results indicate the prospect of using C60 as a potential protective nano agent to improve the efficiency of skeletal muscle function by modifying the reactive oxygen species-dependent mechanisms that play an important role in the processes of muscle fatigue development.

Thioterpenoids as Potential Antithrombotic Drugs: Molecular Docking, Antiaggregant, Anticoagulant and Antioxidant Activities

Natural monoterpenes and their derivatives are widely considered as effective ingredients for the design and production of new biologically active compounds with high antioxidant, antimicrobial and anti-protozoa properties. In this study, we synthesized two series of thiotherpenoids "sulfide-sulfoxide-sulfone", with different bicyclic monoterpene skeleton (bornane and pinane) structures. The effect of the obtained compounds on platelet aggregation was investigated by using the molecular docking technique. The obtained data revealed that all the synthesized compounds may act as potential inhibitors of platelet aggregation. Moreover, the studied sulfides have shown high antioxidant activity as revealed by lipid peroxidation (LPO) process inhibition in a non-cellular substrate containing animal lipids. The sulfides were able to inhibit erythrocyte oxidative hemolysis, to reduce the accumulation of secondary LPO products in cells and to prevent the oxidation of native oxyhemoglobin. Additionally, the corresponding sulfones and sulfoxides exhibited insignificant antioxidant activity. However, the sulfides were found to exhibit significant antiaggregant and anticoagulant effects. These findings suggest as well that the sulfides could serve as a leader compound for future research and possible practical applications.

Determination of trans-4-hydroxy-2-alkenals in thermally treated soybean oil by SPE-HPLC

Trans-4-hydroxy-2-hexenal (4-HHE) and trans-4-hydroxy-2-nonenal (4-HNE) are secondary lipid peroxidation products in edible oils, which are cytotoxic and genotoxic. They could covalently bind with protein, phospholipids and DNA, further disrupting the normal function of liver, lung and brain. Derivation process was generally conducted during pretreatment before detection and quantification of 4-HHE and 4-HNE. However, the derivation procedures were time consuming and chemical degradation may occur during the process. Hence, this paper aims to establish a simple solid phase extraction-high performance liquid chromatography (SPE-HPLC) method to determine the 4-HHE and 4-HNE contents in thermally treated soybean oil. C18 solid phase extraction was applied in the pretreatment process. Firstly, the reliability of the method was evaluated. Good linearity was observed in the range of 0.1–0.5 μg/mL and 0.5–10 μg/mL for 4-HHE and 4-HNE. The limit of detection (LOD) of 4-HHE and 4-HNE were 0.0486 and 0.0129 μg/mL, respectively. And the limit of quantitation (LOQ) of 4-HHE and 4-HNE were 0.1458 and 0.0431 μg/mL, respectively. Recovery rate were in the range of 89.11%–91.58% and 71.83%–79.40% for 4-HHE and 4-HNE, respectively. The method achieved the extraction, purification and detection of 4-HHE and 4-HNE simultaneously and had the advantages of simple operation, effectiveness, high precision, good repeatability. Then, the method was applied to monitor the concentrations of 4-HHE and 4-HNE in soybean oil heated at 180 °C for 40 h. The contents of 4-HHE and 4-HNE were 0–0.32 μg/g and 0–6.97 μg/g, respectively, which provided guidance for evaluating health risks of thermally treated soybean oil during heating.

Changes of Lipid Peroxidation after Administration of Nanomodified Resuspending Solution into Donor Red Blood Cells

The problem of increasing the functional activity preservation of red blood cells is priority for the Blood Service and clinical transfusiology. Taking into account the previously discovered unique properties of magnetite nanoparticles, namely: nonspecific modulation of metabolic processes, strengthening of adaptive mechanisms of cellular organelles, acceleration of reparative processes at the level of membranes and macromolecules, for the first time an attempt was made to use the upgraded saline solution of sodium chloride (nanotechnologically upgraded solution - NUS) as a resuspending of erythrocyte-containing components (ECC). Objective: to improve the preservation of red blood cells containing donor blood components using NUS for resuspending. To achieve this goal, the first stage of the study examined the effect of a new resuspending solution (NUS) on lipoperoxidation, catalase activity, and red blood cell peroxidation resistance in donor blood components containing red blood cells. Object of Research: red blood cells from preservation blood of donors, which are intended for component transfusion therapy. As a result of the study, the advantages of using NUS were established, namely: a significant decrease in the levels of primary and secondary lipid peroxidation products in the first 15 days of observation, an increase in catalase activity and resistance of red blood cells to peroxidation in the first stages of the study, inhibition of the shear reaction with neutral lipid peroxidation in the late stages of observation.

Lipid peroxidation and lipid-soluble antioxidants as quality control markers in cold-stored fruit for establishing commercial acceptability in Bacon avocados

Avocados are prone to chilling injury disorders when stored at low temperatures. Although most studies have been performed in the worldwide distributed ‘Hass’ variety, other less exploited commercial varieties such as ‘Bacon’ might be more cold-tolerant. Aiming at evaluating how cold storage influences chilling injury, the extent of lipid peroxidation and the contents of lipophilic antioxidants were measured in ‘Bacon’ avocados. Harvested fruit were divided into two groups: one stored for 6 weeks at 4 °C and sampled at various time intervals for 42 days, and the other maintained at low temperatures for 3 and 6 weeks and then exposed to room temperature for 5 days until ripened. Long-term cold storage negatively influenced tocochromanols and carotenoids composition in unripen fruit, decreasing progressively both vitamin E and plastochromanol-8 contents, and most particularly carotenoids; yet chilling injury was prevented during cold storage for 6 weeks. When these fruits were ripened at room temperature, chilling injury increased 20% in the peel but only 5% in the mesocarp (edible part). Enhanced chilling injury in the mesocarp was associated with a 2.3-fold increase in lipid hydroperoxides (a primary lipid peroxidation product) and a 2.5-fold increase in plastochromanol-8 content, while contents of other tocochromanols, carotenoids and malondialdehyde (a secondary product of lipid peroxidation) kept unaltered. Interestingly, medium-term cold storage (3 weeks at 4 °C) did not lead to chilling injury in ripe fruit, therefore cold storage for 3 weeks is considered optimal to prevent large antioxidant vitamin degradation and maintain fruit quality in ripen avocados. In conclusion, despite the high cold tolerance shown by ‘Bacon’ avocados, fruit showed a strong depletion (60%) in carotenoids content after 6 weeks of storage at 4 °C, negatively affecting their commercial acceptability. Aside from evaluating visual chilling injury symptoms, evaluation of lipid peroxidation markers and contents of lipid-soluble antioxidants are deemed to be essential to establish commercial acceptability in cold-stored fruit.

Effect of a novel thiazole derivative and its complexes with polymeric carriers on the processes of lipid peroxidation in lymphoma cells

Background. Many types of tumors are sensitive to changes in prooxidant-antioxidant balance. Thus, further studies on reactive oxygen species inducing antitumor drugs that generate oxidative stress-dependent cytotoxic effects are promising. Our previous works showed that thiazole derivatives in combination with polymeric carriers have a pronounced cytotoxic effect on tumor, while not being cytotoxic against pseudo-normal cells in vitro. It was found that thiazole derivatives in complex with PEG-based polymeric carriers affected the antioxidant system of lymphoma cells in vitro. The aim of this work was to study the in vitro effect of the complex of thiazole derivative N-(5-benzyl-1,3-thiazol-2-yl)-3,5-dimethyl-1-benzofuran-2-carboxamide (BF1) in combination with polymeric carriers poly(VEP-co-GMA)-graft-mPEG (Th1), poly(PEGMA) (Th3) and poly(PEGMA-co-DMM) (Th5) on the level of lipid peroxidation products in NK/Ly cells. Materials and Methods. The experiments were conducted on white wild-type male mice with a grafted NK/Ly lymphoma. Ascites tumor cells were inoculated into mice intraperitoneally. Abdominal drainage with ascites of anesthetized mice was performed with a sterile syringe on the 7th–10th days after inoculation. Investigated compounds BF1, polymeric carriers Th1, Th3, Th5 and combination of BF1 + Th1 (Th2), BF1 + Th3 (Th4) and BF1 + Th5 (Th6) at a final concentration of 10 μM were added to the lymphoma samples and incubated for 10 minutes. The level of lipid peroxidation products, such as lipid hydroperoxides and thiobarbituric acid-positive products) were determined according to the techniques described below. Results. All applied complexes based on thiazole derivative BF1 and PEG-based polymeric carriers at a concentration of 10 μM increased the activity of lipid hydroperoxi­des in the lymphoma cells by 29–36% compared to control. Complexes Th2 and Th6 increased the significance of BF1 influence on lymphoma cells from P <0.05 to P <0.01. Among all of the studied complexes, Th4 and Th6 significantly increased the level of TBA-positive products, while Th2 and BF1 did not change the content of the secondary products of lipid peroxidation. None of the unconjugated polymeric carriers affected the level of lipid peroxidation products. Conclusions. Thus, based on the results of this work, thiazole derivative BF1 in complex with polymeric carriers increases the level of primary and secondary products of lipid peroxidation in lymphoma cells. Polymeric carriers enhanced the effect of thiazole derivative on the studied parameters, so complexes of thiazole derivatives and PEG-containing polymeric carriers should be taken into consideration and further investigated as potential antitumor agents.

Oxidative Stress Index Levels in Asian Adolescents with Exogenous-Constitutional Obesity

The aim of this research was to evaluate the integral oxidative stress index (OSI) level in Asian girls and boys with exogenous-constitutional obesity. Methods and Results: A total of 170 Asian adolescents aged 12-18 years were examined: 26 girls and 28 boys with constitutional obesity (main group, MG); 59 girls and 57 boys - healthy adolescents (control group, CG). The levels of lipid peroxidation (LPO) products and antioxidant defense (AOD) parameters were detected using spectrophotometric and fluorometric methods. The level of LPO products and AOD components in the studied groups were assessed to calculate the integral OSI. Significant increases in the levels of primary LPO products (conjugated dienes by 2.18 times) and secondary LPO products (ketodienes and conjugated trienes by 2.48 times) in the obese Asian girls, compared with the control values, were observed. We found a significant decrease in the parameters of the AOD system in the obese Asian girls, compared with the control values: α-tocopherol (by 1.41 times; P=0.0262), retinol (by 1.12 times; P=0.0306), and SOD activity (by 1.28 times; P=0.0004). In the obese Asian boys, increased values of LPO components were found, compared to controls: conjugated dienes (by 2.13 times), ketodienes and conjugated trienes (by 3.4 times), final thiobarbituric acid reactants of LPO (by 1.24 times). They showed a statistically significant decrease in the level of α-tocopherol (by 1.49 times), compared with the control values. According to the obtained data, OSI in the group of Asian girls with obesity was 15.68 units, in the group of Asian boys with obesity - 22.89 units. The OSI in the group of Asian boys was higher (by 1.46 times) than in the obese girls. Conclusion: Certain OSI levels are consistent with the presence of antioxidant insufficiency in exogenous-constitutional obesity and allow us to specify and evaluate the ethnic aspect of the severity of the pathological process more reliably.

Prospective study of the cytokine profile and antioxidant status of patients with pyoderma

Background. The importance of studying the pathogenetic features of pyoderma associated with Streptococcus pyogenes is associated with the severity of the course of the disease, frequent relapses with a short inter-relapse period, and long-term disability.The severity of the course, long-term disability, violations of the pro-oxidate mechanisms recorded in patients with poidermias associated with Streptococcus pyogenes are priority and timely.
 Aims. Study of the cytokine, prooxidant and antioxidant profiles of patients with pyoderma associated with Streptococcus pyogenes.
 Мethods. А prospective study of the cytokine profile, the level of antioxidant defense enzymes, and lipid peroxidation factors in patients with pyoderma, lasting more than 2 years, associated with Streptococcus pyogenes, was carried out. The study included 100 people with diffuse lesions of smooth skin, identified on the skin surface of Streptococcus pyogenes, at the age of 28.76 6.24 years; in blood serum, the content of cytokines IL-2, IL-8, IL-10, TNF-, IFN-, IL-1 was studied by enzyme immunoassay, in whole blood the content of primary, secondary and final products of lipid peroxidation, antioxidant enzymes protection superoxide dismutase and catalase.
 Results. Analysis of the content of cytokines showed a significant decrease in the concentration of IL-2, an increase in IL-10, TNF-, IL-8, IL-1 in the blood serum of patients with streptoderma compared with the reference values of healthy people (p 0.05). In whole blood plasma, an increase in the concentration of primary, secondary and final products of lipid peroxidation was registered with a significant decrease in the activity of antioxidant enzymes of superoxide dismutase and catalase relative to the indicators of healthy volunteers (p 0.05).
 Conclusions. In patients with streptoderma, an increase in the production of cytokines with pro-inflammatory and chemotactic properties in response to the invasion of the pathogen and its persistence was revealed. The intracellular nature of the parasitization of Streptococcus pyogenes contributes to the enhancement of the systemic and local inflammatory process, the formation of oxidative stress, the accumulation of primary, secondary and final products of lipid peroxidation, and a decrease in the activity of antioxidant enzymes. A decrease in the content of interleukin 2, which has immunoregulatory properties in patients with streptoderma, leads to impaired immune homeostasis, a decrease in the processes of differentiation in the direction of the Th1 immune response, proliferation of T-lymphocytes, a violation of the qualitative and quantitative composition of the main subpopulations of peripheral blood lymphocytes, which is clinically expressed in this occurrence of relapses in categories of patients.