Activity Of Antioxidant System Enzymes Research Articles

Changes in the Antioxidant System of Germinating Seeds and Sprouts of Pea with the Use of Micellar-Substrate Extract of Oyster Mushrooms

The reactions of the antioxidant system (AOS) of daily germinating seeds and 8-day-old pea seedlings cultivated using 10% and 100% aqueous extract from spent oyster mushroom straw substrate (hereinafter extract) were studied. The mother liquor was taken for 100% extract after its preparation, and the 10% was obtained by diluting the mother liquor. The plants were grown in oligotrophic hydroponic conditions and in eutrophic conditions on gray forest soil. The activity of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), expression of SOD-1, CAT-1, POD genes, and the content of low molecular weight antioxidants (NMAO): ascorbate, phylloquinones, and free proline were studied as the main indicators of the AOS reaction. The inhibitory effect of 10% and 100% extract on the activity of SOD and CAT, but not on the activity of POD in daily germinating seeds, has been shown. At the same time, the content of mRNA transcripts of the SOD-1 and POD genes decreased only slightly in seeds cultivated with 100% extract, in the remaining experimental groups the level of gene expression did not differ from the control. The content of ascorbate in all experimental groups did not differ from the control, and phylloquinones and free proline were less than in the control. In the leaves of 8-day-old seedlings cultivated in a hydroponic medium, in all experimental groups, the activity of AOS enzymes, the expression of their coding genes and the content of phylloquinones and free proline did not differ from the control. At the same time, the ascorbate content was higher. In plants cultivated in soil using a 10% extract, all EPA indicators did not differ from the control. In plants grown using 100% extract, the activity of SOD, the expression level of the SOD-1 gene, the content of ascorbate and free proline were higher, and the remaining indicators did not differ from the control. Thus, the extract at the initial stages of germination inhibited the AOS of peas, followed by restoration (in oligotrophic conditions) and enhancement (in eutrophic cultivation conditions) of its work.

The effect of hypochlorous acid inhalation on the activity of antioxidant system enzymes in rats of different ages

Hypochlorous acid HOCl is an effective disinfectant with a broad spectrum and high rate of microbicidal action. Its use for air treatment can be an effective tool for the prevention and therapy of infectious diseases. In this work, the in vivo study was conducted on 110 Wistar Han rats (12 and 72 weeks old) on the effect of a single inhalation of air containing gaseous HOCl on the activity of antioxidant system enzymes. For this, a special installation was designed to uniformly maintain the concentration of HOCl in the air and regulate it over a wide range. Inhalation exposure was carried out for 4 h at total chlorine concentrations in the air of approximately 2.0 mg/m3 and 5.0 mg/m3, after which the animals were observed for 14 days. The effect of inhalation on the antioxidant system activity varied significantly in animals of different ages. Catalase activity in young rats increased approximately 2-fold on days 1-2 after inhalation, regardless of the HOCl concentration, while in old animals a sharp dose-dependent decrease was initially observed. The glutathione peroxidase activity in animals of both ages increased upon inhalation of air with 5.0 mg/m3 HOCl, and in old animals this was more pronounced; when the HOCl concentration decreased to 2.0 mg/m3, this indicator increased slightly in old rats and remained virtually unchanged in young ones. The glutathione reductase activity when exposed to 2.0 mg/m3 HOCl did not change for both age groups, and with increasing HOCl concentration it increased by 1.5-2.0 times in all animals.

Changes in the level of the ingredients of the products of lipid peroxidation and the activity of antioxidant system enzymes in the blood of sows in case of violation of the microclimate parameters of the premises and their correction with oxidoprotectors

Changes in the level of the ingredients of the products of lipid peroxidation and the activity of antioxidant system enzymes in the blood of sows in case of violation of the microclimate parameters of the premises and their correction with oxidoprotectors

Effects of supplementation with different zinc-based products on the growth and health of Nile tilapia

Zinc is one of the essential microelements for the metabolism of animals. Zinc nanoparticles may have higher bioavailability due to their low specific surface area, facilitating absorption by fish. The present study aimed to evaluate the effects of supplementation with different zinc-based products on the growth and health of Nile tilapia Oreochromis niloticus. Zinc, in different sizes (nanoparticles or bulk) and forms (inorganic or organic), were used as a supplement in the tilapia diet at a dose of 15 mg kg feed−1 for 60 days. At the end of the feeding trial, production performance, hemato-immunological parameters, activity of antioxidant system enzymes, exposure to Streptococcus agalactiae and zinc concentration in the muscle were examined. After the bacterial challenge, the mean corpuscular hemoglobin concentration (MCHC) significantly increased in the fish treated with organic zinc, inorganic nano zinc, and organic nano zinc, while in the control group (inorganic zinc), MCHC remained unchanged. Regarding defense cells, dietary inorganic nano zinc increased the number of basophils (1.50 ± 1.10) compared to organic zinc (0.80 ± 0.90). Lymphocyte count increased after the challenge only in the organic zinc treatments (bulk and nanoparticles). Neutrophils decreased in the control (inorganic zinc) (2.20 ± 1.70) and inorganic nano zinc (2.60 ± 2.70) treatments after the challenge. When compared before and after the bacterial challenge, the plasma antimicrobial titer significantly increased after the bacterial challenge in all treatments. No significant differences were observed for total proteins, enzymes (SOD and CAT), cumulative survival and zinc deposition on fillet. In conclusion, organic zinc in nanoparticles or bulk size increased Nile tilapia innate defense during bacterial infection. However, the other parameters evaluated were not affected by zinc particle size or form (organic or inorganic), indicating that further evaluations should be conducted with organic zinc in nanoparticles or bulk size in the tilapia diet.

Metabolic stress and stress-limiting mechanisms in bronchial asthma combined with type 2 diabetes mellitus

Objective: to study the indicators of lipid peroxidation and the antioxidant system in the blood and moisture condensate of exhaled air in patients with AD combined with type 2 diabetes, and in the blood of these patients — total metabolites of nitric oxide. Materials and methods: the study involved 215 patients with persistent BA of moderate severity aged (38.6±2.4) years, including 88 men (40.9%), 127 women (59.1%). Among the examined patients with BA there were 64 — group I, persons with BA combined with type 2 diabetes — 151 (group II). The parameters of the lipid peroxidation system (LPS) in the blood serum were studied: malondialdehyde (MDA), diene conjugates (DC), and the antioxidant system (AOS) according to the activity of catalase and superoxide dismutase (SOD), the amount of total metabolites of nitric oxide (NOx), in the condensate of exhaled air moisture (KEAM) was determined general oxidant (GOA) and antioxidant (AOA) activity. Results: in patients with BA combined with type 2 diabetes, an increase in the concentration of POL products in the blood was revealed: MDA was 2.6 times (p<0.05) compared with the control group and 1.3 times (p<0.05) compared with the indicator in patients with AD, DC, respectively, 2.0 times (p<0.05) compared with the control group and 1.2 times (p<0.05) compared with I group. The activity of the enzymes AOS catalase and SOD in patients with comorbidity of BA and type 2 diabetes was found to be lower than in patients of group I. In the KEAM of patients with comorbidity of BA and type 2 diabetes, a significant increase in OOA and a decrease in OAA were noted. The concentration of NOx in the blood serum of group II patients was 1.6 times higher than in the control group (p<0.05), but 1.4 times lower than in patients with AD without comorbidity with type 2 diabetes (p<0.05). The direction of the revealed correlations between the products of POL in blood serum and KEAM confirmed the systemic nature of metabolic changes in the body of patients with AD, and their strength in group II patients — the negative effect of comorbid type 2 diabetes on the greater severity of these metabolic changes. Conclusions: the resulting changes in the state of LPS and AOS in the blood and KEAM of patients with BA combined with type 2 diabetes can be characterized as systemic metabolic stress, both components of which: oxidative and nitrosive are supported by insufficient stress-limiting mechanisms — low activity of AOS enzymes and possible depletion of nitric oxide production, which should be reflected in the means of correcting metabolic disorders in patients with this comorbidity.

Gold nanoparticles (AuNPs) decrease the viability of cervical cancer cells by inducing the BAX gene and activating antioxidant enzymes.

Cervical Cancer (CC), a leading cause of female mortality worldwide, demonstrates a direct association with high-risk human papillomavirus (HPV) infections. However, not all CC patients exhibit HPV infection, suggesting additional predisposing factors. Recently, disturbances in the oxidant-antioxidant balance have been implicated in CC development. This study explores the impact of gold nanoparticles (AuNPs) on the survival and antioxidant capacity of HeLa cells, aiming to contribute to novel CC therapy approaches. Synthesized and characterized AuNPs (25.5nm, uniform distribution according to the DLS analysis) were administered to HeLa cells at varying concentrations. After 24h, cell viability was assessed using the (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) (MTT) assay. Real-time PCR measured expression levels of apoptosis-related genes (BCL2 associated X (BAX) and p53). Catalase and superoxide dismutase (SOD) activities, key antioxidant enzymes, were also evaluated post-AuNP treatment. AuNPs dose-dependently reduced HeLa cell viability, with an IC50 value of 113µg/ml. BAX gene expression significantly increased, indicating pro-apoptotic effects. Moreover, enzyme activities significantly rose under AuNP influence. AuNPs demonstrated the potential to induce HeLa cell death by upregulating pro-apoptotic BAX gene expression and altering antioxidant system enzyme activities. These findings underscore the promise of AuNPs as a therapeutic avenue for CC, emphasizing their impact on crucial cellular processes involved in cancer progression.

Metal-accumulating capacity and antioxidant activity of Pylaisia polyantha (Hedw.) Schimp. moss in urban areas

Background. Bryophytes, including mosses, are widely used in biomonitoring of atmospheric pollution due to their ability to accumulate metals from atmospheric air. However, the effects of metal accumulation on metabolic processes in bryophyte cells have not been thoroughly studied. The aim of this work was to analyse the accumulation of heavy metals, indices of lipid peroxidation (LPO), and antioxidant status in gameto­phytes of the epiphytic moss Pylaisia polyantha (Hedw.) Schimp. collected from urban areas with different levels of technogenic load. Materials and Methods. The study was conducted in the city of Lviv (western part of Ukraine). Within the city, 15 sampling sites were selected and grouped as fol­lows: the green zone (A) conditionally used as the control, zone influenced by transport activities (B) and the industrial zone (C). In gametophyte shoots of P. polyantha, con­centrations of heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) were analysed using the method of atomic absorption spectrophotometry; the content of LPO products (lipid hydroperoxides, thiobarbituric acid reactive substances (TBARS)) and the activities of antioxidant system enzymes (superoxide dismutase, catalase, glutathione S-transferase) were analysed using standard methods. The results were processed using standard statistical methods. Results. Concentrations of heavy metals in P. polyantha gametophytes collected from the study area can be arranged in descending order as follows: Fe> Mn> Zn> Pb> Cu> Ni> Cr> Co> Cd. The content of individual metals in moss material varied depending on the sampling site. Moss shoots collected from zone B accumulated significantly higher levels of Cd, Co, Cu, Fe, Mn, Pb and Zn, and shoots from zone C had higher levels of Cr and Zn compared to those from the green zone. Moss gametophytes col­lected from sites in zone B had higher concentrations of LPO products and increased levels of antioxidant enzymes activity compared to the control. Conclusions. Elevated concentrations of heavy metals in moss material from sites exposed to traffic and industrial activities reflect atmospheric heavy metal pollution in urban areas. Intensive accumulation of heavy metals in gametophytes of P. polyantha that grows in the areas of transport activities is accompanied by increased lipid peroxi­dation processes and activation of enzymes of the antioxidant system in moss cells. Activation of antioxidant enzymes may play an important role in the adaptation of the moss P. polyantha to urban environments contaminated with heavy metals as a result of anthropogenic activities.

Enhancement of salt tolerance of transgenic Arabidopsis thaliana by Zostera japonica DnaJ gene

Abstract Soil salt damage has become one of the main biological stresses affecting plant seed germination, crop growth and yield. Salt damage can lead to the accumulation of superoxide anion, hydrogen peroxide and hydroxyl free radicals in plants, and a large amount of accumulated reactive oxygen species will cause the oxidation of lipids, proteins and nucleic acids and then cause cell damage. In this experiment, the seedlings and adult plants of transgenic Arabidopsis with overexpression of Zostera japonica (Z. japonica) DnaJ gene ZjDjB1 were used as materials. Wild-type and transgenic ZjDjB1 Arabidopsis were treated with 100 mM and 200 mM NaCl and root length, fresh weight, leaf water content and dry weight, physiological indexes and antioxidant system enzyme activities were measured. The results showed that overexpression of Z. japonica DnaJ gene ZjDjB1 could significantly alleviate the damage caused by salt stress to transgenic ZjDjB1 Arabidopsis seedlings and adult plants. The results showed that overexpression of Z. japonica DnaJ gene ZjDjB1 could reduce the content of MDA and O2-, increase the content of proline and activate the enzyme activity of antioxidant system under salt stress, to reduce the damage of salt stress to plants.

Study on the Mechanism of Grafting to Improve the Tolerance of Pepper to Low Temperature

Pepper is a horticultural crop that does not tolerate low temperatures. To investigate how the grafted pepper responds to low temperature stress in the short term, transcriptome analysis was performed on grafted seedlings treated with low temperature for 1 h, 4 h, 12 h and 24 h compared with those treated for 0 h. The results showed that genes related to CAM4, MPK8, RbohD and OXI1 might be related to the response of grafted seedlings to low temperature stress in the short term. To investigate how low temperature tolerant rootstocks can improve the low temperature tolerance of grafted peppers, morphological and physiological indices of self-rooted and grafted seedlings were analyzed under low temperature conditions for different days. The results showed that the degree of wilting, REL and MDA content of grafted seedlings were significantly lower than those of self-rooted seedlings, and the antioxidant enzyme activities were significantly higher than those of self-rooted seedlings under low temperature stress. The results indicated that grafted pepper would activate ROS-related genes in a short period of time after low temperature stress and produce a large amount of ROS in response to the low temperature stress. When ROS accumulated to a certain level, the grafted pepper could increase the enzyme activity of antioxidant system to remove the ROS produced in the body, and help the pepper seedlings adapt to low temperature stress through osmoregulation mechanism, so as to resist the damage caused by low temperature. The results of the study provide ideas for growing pepper in low temperature environment.

Acetone O-(4-chlorophenylsulfonyl)Oxime as an Agent Alleviating the Adverse Effects of Drought Stress in Maize

The negative effects of drought stress, which is the most effective type of stress on the yield loss of crops with a rate of 26% among abiotic stresses, are increasing day by day with global warming. The purpose of the study is to find out if Acetone O-(4 chlorophenylsulfonyl) oxime (AO) has positive effects on the metabolism of maize seedlings under drought or not. The following experimental setup was established: 18 hours distilled water Control (C), 6 hours 0.66 mM AO+12 hours distilled water (AO), 6 hours distilled water+12 hours 3% PEG (D), and 6 hours 0.66 mM AO+12 hours 3% PEG (AO+D). While ABA content decreased in AO application compared to control, it was determined that ABA decreased in AO+D application compared to D. While a difference could not be determined between AO by control and between D by AO+D applications on RWC content, it was observed that stress significantly reduced in RWC. It was determined that AO increased the Photosynthetic pigment content in the AO+D compared to the D. It was determined that AO reduced MDA and H2O2 content by regulating the activities of antioxidant system enzymes. It was observed that the proline content increased in AO application compared to control and in AO+D application compared to D. While ASA content decreased in AO application compared to control, it was determined that ASA content increased in AO+D application compared to D. Significant fluctuations in the contents of phenolic substances were determined. As a result, the pre-application of AO to maize under drought stress may prevent the formation of radicals, and this situation is thought to be due to the antioxidative properties of AO.

Hexavalent chromium-induced toxic effects on the hematology, redox state, and apoptosis in Cyprinus carpio

In recent years, hexavalent chromium [Cr (VI)]has been widely used in the electrochemical industry, posing potential threat to aquatic animals The objective of this study was to investigate the toxic effects of waterborne Cr (VI) on hematology, digestive enzyme, redox state, and apoptosis in Cyprinus carpio. In this study, 300 C. carpio were randomly divided into four groups and exposure to 0 (Control), 0.5, 1 and 2 mg/L Cr (VI) for 28 days, respectively. The result showed that Cr (VI) exposure exerted significant toxic effects by reducing in the levels of hematology parameters (hemoglobin, erythrocytes) and serum calcium, increasing serum biochemistry (glucose, cholesterol and ALT), decreasing digestive enzyme (lipase and amylase). The waterborne Cr (VI) exposure significantly increased oxidative stress levels by increasing the levels of MDA, ROS and PC, interfering with the enzyme activities of antioxidant system (SOD, CAT, AHR, GSH, GSH-Px, GR and GST) and finally breaking the redox state in C. carpio. Additionally, our study found that waterborne Cr (VI) exposure induced intestinal and liver apoptosis in different ways was mainly related to death receptor pathway and mitochondrial pathway, respectively. Our results suggest that exposed to waterborne Cr (VI) above 0.5 mg/L has potential toxic effects in C. carpio.

Antioxidant status of fish with inflammation of the swim bladder in yearling carp

The literature data on the etiology and pathogenesis of swim bladder inflammation (SBI) in various fish species have been highlighted in the paper. The main goal of this work was to analyze the impact of the disease on the physiological status of the body of the yearling carp, the state of the antioxidant defense system, and the content of lipid peroxidation products (LPP). The yearling Liubyn scaly carps, with an average weight of 40 g, which were grown in the ponds of the Rivne fish and reclamation station, were selected for experimental research. During control catches and ichthyopathological examination of forty fish, inflammation of the swim bladder was detected with an intensity of 35 %. During the pathological autopsy of this yearling carp, thickening of the walls of the swim bladder with purulent exudate, atrophy of the posterior lobe, and hyperemia of internal organs was found. Data on the content of lipid peroxidation products (LPP) and the state of the antioxidant system (AOS) in the cells of the hepatopancreas and skeletal muscles of this year's carp with SPM have been presented. It was determined that in the hepatopancreas of fish with the swim bladder inflammation, primary and secondary LPP products accumulate, and the activity of AOS enzymes decreases. The increase of diene conjugates in the hepatopancreas of the diseased fish was revealed by 11.8 % compared to the control group, and the content of TBC-active products by 29.8 %. The level of SOD activity is 13.5 % lower in the fish affected by SMP than in the control group. Catalase activity in the hepatopancreas of the diseased fish increases by 11.7 % compared to the control group. There was a 45.5 % decrease in superoxide dismutase activity in the skeletal muscles of fish affected by SBI and a significant increase in the level of catalase (Р < 0.01) compared to the control group. Pathogens that cause diseases of the swim bladder cause also have an inhibitory effect on the activity of enzymes of the antioxidant system, and the content of products of lipid peroxidation increases.

Indicators of lipid peroxidation and the activity of antioxidant system enzymes as predictors of the development of metabolic disorders in primary obesity

Aim. To assess the effectiveness of indicators of lipid peroxidation and the activity of antioxidant system enzymes in the early diagnosis of metabolic disorders.
 Methods. The study included 269 women of fertile age with primary obesity. The control group consisted of 35 women. The clinical examination included identification of the type of obesity, whole-body fat percentage, the level of glycemia and the index of insulin resistance, biochemical markers of lipids, hormones (leptin and insulin), malondialdehyde and enzyme activity (peroxidase and catalase). The statistical significance of the differences was determined by using the inversion test. Spearman's rank correlation coefficient was used to assess the degree of relationship between quantitative characteristics, and scatter diagrams were used to compare two variables (Statistica software version 10.0).
 Results. A statistically significant increase in basal and stimulated immunoreactive insulin was found in obese patients compared with the controls (p 0.01). Stimulated immunoreactive insulin levels, insulin resistance score (HOMA-IR) and the level of leptin in the group of patients with android obesity was higher than in the group with gynoid obesity (p 0.01). The relationship between the concentration of serum malondialdehyde and whole-body fat percentage was found to be more significant (r=0.412; p 0.001) than the relationship with the type of obesity (r=0.257; p 0.01). Positive correlations were found between serum malondialdehyde and insulin (r=0.35; p 0.001) and leptin (r=0.32; p 0.001) levels. The relationship between the concentration of serum malondialdehyde and the activity of enzyme systems was also noted. The activity of lipid peroxidation was higher in the group of patients with android obesity (malondialdehyde 3.3 mol/L) compared with the group of patients with gynoid obesity. In the same group, a higher activity of enzyme systems was noted.
 Conclusion. An increase in the concentration of serum malondialdehyde and the activity of enzyme systems should be considered as indicators of a high risk of developing metabolic syndrome.

Impact of environmental mercury exposure on the blood cells oxidative status of fishermen living around Mundaú lagoon in Maceió – Alagoas (AL), Brazil

Mercury in the aquatic environment can lead to exposure of the human population and is a known toxic metal due to its capacity for accumulation in organs. We aimed to evaluate the mercury level in the blood and urine of fishermen and correlate it with the level of oxidative stress in blood cells. We show in this case-control study that the fishermen of the exposed group (case) of Mundaú Lagoon (Maceió - Alagoas, Brazil) have higher concentrations of total mercury in the blood (0.73–48.38 μg L−1) and urine (0.430–10.2 μg L−1) than the total mercury concentrations in blood (0.29–17.30 μg L−1) and urine (0.210–2.65 μg L−1) of the control group. In the blood cells of fishermen, we observed that the lymphomononuclear cells produced high levels of reactive oxygen species (61.7%), and the erythrocytes presented increased lipid peroxidation (151%) and protein oxidation (41.0%) and a decrease in total thiol (36.5%), GSH and the REDOX state (16.5%). The activity of antioxidant system enzymes (SOD, GPx, and GST) was also reduced in the exposed group by 26.9%, 28.3%, and 19.0%, respectively. Furthermore, hemoglobin oxygen uptake was decreased in the exposed group (40.0%), and the membrane of cells presented increased osmotic fragility (154%) compared to those in the control group. These results suggest that mercury in the blood of fishermen can be responsible for causing impairments in the oxidative status of blood cells and is probably the cause of the reduction in oxygen uptake capacity and damage to the membranes of erythrocytes.

Kuraklık Stresi Altında Sarı Kantaronun (Hypericum perforatum L.) Fizikokimyasal ve Antioksidan Tepkileri

This study investigated the effects of drought stress on the physiological and biochemical responses of the medicinal and aromatic plant Hypericum perforatum (St. John’s Wort). Changes were determined in leaf length, relative water content (RWC), osmotic potential, chlorophyll fluorescence (Fv/Fm), lipid peroxidation (TBARS), hydrogen peroxide (H2O2), and proline content as well as in the antioxidant system enzyme activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX), and glutathione reductase (GR). These responses were examined in relation to the tolerance of drought stress in H. perforatum. Ninety-day-old seedlings were subjected to drought for three weeks. The physiological parameters of leaf length, RWC, Fv/Fm, and osmotic potential were reduced under drought. The H2O2, TBARS, and proline levels were increased significantly under drought stress. Moreover, the proline content increase was greatly pronounced (25.9-fold) compared to the control groups. The high accumulation of proline may have resulted from the 83.8% leaf RWC still remaining under drought stress. On the other hand, the SOD, CAT, and GR enzyme activities were enhanced, whereas the POX and APX activities were reduced. The results indicate that improved tolerance to drought stress in H. perforatum plants may be accomplished through increased capacity of the antioxidative defense system

Salicylic Acid Effects on Flue-Cured Tobacco Quality and Curing Characteristics During Harvesting and Curing in Cold-Stressed Fields.

Salicylic acid (SA) can induce plants to actively enhance abiotic stress resistance. Spraying SA to prevent cold stress in flue-cured tobacco fields can provide theoretical support and practical guidance for the actual protection from cold stress in fields at high altitude in Yunnan. The experiment was performed in Jianchuan County Yunnan Province, China. Honghuadajinyuan, a flue-cured tobacco variety with cold resistance, was used as the research object. SA was tested at two concentrations (0.05 [SA-1] and 0.1 [SA-1] mol L–1) relative to an untreated control (Control) to compare the quality of fresh tobacco leaves, curing characteristics, enzyme activity of antioxidants, and quality of the first-cured tobacco leaves. The tissue structure thickness, SPAD, and plastid pigment content of fresh tobacco leaves were least in the control; there was no significant difference between SA-1 and SA-2. The change of moisture content during curing was SA-1 > SA-2 > Control, and the water loss rate was Control > SA-2 > SA-1, and both varied greatly at 38–48°C. In each curing stage, the carbon and nitrogen metabolites and polyphenols changed most rapidly at 38°C, and the sugar metabolites changed as follows: Control > SA-1 > SA-2. The activities of the antioxidant enzymes superoxide dismutase, peroxidase, and catalase in fresh tobacco leaves were SA-1 > SA-2 > Control. Malondialdehyde content and the inactivation rate of antioxidant enzymes during curing was Control > SA-2 > SA-1. The economic character and sensory smoking quality of flue-cured tobacco leaves were SA-1 > SA-2 > Control. In high-altitude tobacco planting areas prone to cold stress in the field, early warning weather forecast and field spraying 0.05 mol L–1 SA are beneficial to protect and improve the quality of fresh tobacco leaves, curing characteristics, antioxidant system enzyme activities, and the quality of flue-cured tobacco leaves.

Impact of hot water-calcium on the activity of cell wall degrading and antioxidant system enzymes in mango stored at chilling temperature.

Mango can develop symptoms of chilling injury (CI) during storage at low temperatures. The application of a hot water treatment (HWT) prior to cold storage can prevent this disorder; however, prolonged exposure to heat may cause accelerated softening of the fruit. Calcium salts allow the formation of pectates delaying softening and in combination with HWT can reduce the susceptibility to CI. This study evaluated the effect of the quarantine HWT (46.1°C, 75-90min), calcium lactate (CaLac, 0.05%), and their combination (HWT-CaLac) on the activity of cell wall and antioxidant system enzymes in "Keitt" mango stored for 20days (5°C) and during ripening (21°C). HWT and HWT-CaLac reduced CI sensitivity while the combination was more effective to reduce cell wall enzymatic activity and to increase the activity of the antioxidant system enzymes in mango, this demonstrated the usefulness of a HWT-CaLac combination to extend mango storage life by inducing CI tolerance. PRACTICAL APPLICATIONS: Simultaneous application of treatments in diverse crops is significant for prevention of rapid deterioration. In this study, the application of calcium lactate in an established quarantine hot water treatment for mango fruit fly reduced chilling injury presence and stimulated the antioxidant defense mechanism. In this sense, producers and packers can take advantage of this procedure to prolong the storage period of the fruit preserving its postharvest quality and minimizing the risk of chilling injury presence.

COPPER EFFECT ON COMPONENTS OF THE ANTIOXIDANT SYSTEM OF THE DIGESTIVE GLAND IN THE FRESHWATER MUSSEL ANODONTA CYGNEA

The effects of copper accumulation and its impact on the functioning of some components of the antioxidant system (AOS) – CAT, GST, GSH – in the digestive gland of the freshwater mussel Anodonta cygnea were studied in an aquarium experiment. After a 12‑day acclimation, the mussels were divided among aquariums with Cu²⁺ concentrations of 0, 5, 50, 100, and 250 μg/L. Hepatopancreas tissue samples were taken for analysis after 1, 3, and 7 days. Copper ions content, GST and CAT activity, as well as GSH concentration were determined in the tissue. The accumulation process was shown to be doseand time-dependent. The metal accumulated in this concentration was not lethal. The rate of the metal accumulation in the studied organ increased along with the concentration of copper ions in the water. The activity of AOS enzymes in the swan mussel is modified as an adaptation in response to elevated copper concentrations to neutralize the products of oxidative reactions. Changes in the activity of AOS enzymes (CAT and GST) were observed mainly on the seventh day of the experiment at the highest copper concentrations tested. GST proved to be the most stable enzyme. The GSH level in the digestive gland changed 1 day after the start of the experiment, corroborating this tripeptide is involved in the first wave of protection against xenobiotics. Copper ions have a cumulative effect. The changes in enzyme activity observed on day 7 at Cu²⁺ concentration of 250 μg/L suggest that a longer exposure to copper, even in low concentrations, can be detrimental.

Activity of Antioxidant Defense Enzymes in Rats with Experimental Allergic Encephalomyelitis.

We studied activities of antioxidant system enzymes in tissues of rats with experimental allergic encephalomyelitis. It was shown that the development of pathology is accompanied by deformation of the neurons and axonal degeneration, intensification of free radical oxidation, exhaustion of the reduced glutathione pool, and multidirectional changes in activities of antioxidant enzymes in rat tissues. The observed imbalance in the antioxidant defense system can be associated with excessive glutathione utilization in the glutathione transferase reaction and different severity of the pathological process in the brain and spinal cord. The received data necessitate the search for compounds that can prevent inhibition of antioxidant system components in order to analyze the possibility of their use in the treatment of multiple sclerosis.

Silver(I) complexes containing diclofenac and niflumic acid induce apoptosis in human-derived cancer cell lines

We investigated the anti-cancer activity of [Ag(μ-dicl)] n 1 and [AgH(nif)2] 2 complexes against human cancer cell lines (MCF-7, HT-29, and HepG2) and mouse fibroblast (3T3-L1) cell line. Anti-proliferative activity was monitored by XTT cell viability and LDH leakage assays. Cell death mode was evaluated by multi-caspase activity, annexin V cytofluorimetric, MMP, cell cycle arrest, and ROS generation assays. Antioxidant capacity was evaluated on SOD, GPx, GR, and CAT enzymes. The XTT and LDH assay results showed that both complexes exhibited strong cytotoxicity against the tested cancer cell lines. The apoptotic mechanisms of the complexes were demonstrated by loss of MMP and increase in phosphatidylserine translocation, sub-G1 phase, and multi-caspase activity. Besides, both complexes induced the oxidative stress in MCF-7 cells by decreasing the activity of GPx, GR, and CAT enzymes. In conclusion, both Ag(I) complexes, especially 1, warrant for further in vivo evaluation as a new alternative in cancer treatment. Highlights Ag(I) complexes inhibited cell proliferation and induced LDH leakage in human cancer cell lines. Ag(I) complexes induced apoptosis through MMP disruption and ROS generation. Ag(I) complexes mimicked the multi-caspase activity. Ag(I) complexes increased the accumulation of sub-G1 phase. Ag(I) complexes inhibited the activity of antioxidant system enzymes.