Lead-induced increase in antioxidant enzymes and lipid peroxidation products in developing rat brain

Pregnant rats were treated with 0.4% lead acetate through drinking water from 6th day of gestation and this treatment was continued till 21 post natal days (PND). Four regions of the brain namely hippocampus, cerebellum, frontal cortex and brain stem were dissected at 10, 20, 30 and 40 PND for estimation of lipid peroxidation products (LPP), catalase (CAT) and superoxide dismutase (SOD). The results indicate that there was a significant (P < 0.05) increase of LPP in exposed rats than their corresponding control at 10, 20 and 30 PND both in hippocampus and cerebellum. At PND 40, the LPP of control and exposed were found to be almost same in both the tissues indicating recovery from lead toxicity. CAT activity was significantly (P < 0.05) high in hippocampus of exposed rats up to PND 30 but up to PND 20 in cerebellum and frontal cortex. However, in brain stem, a significant (P < 0.05) increase in CAT activity was observed only at PND 10. A significant (P < 0.05) increase in SOD activity was observed up to PND 30 both in hippocampus and cerebellum on lead exposure. Frontal cortex exhibited a similar significant (P < 0.05) increase of SOD activity up to PND 20 and for brain stem up to PND 10. There was no significant change in the activity of antioxidant enzymes (CAT and SOD) and LPP in all the four brain tissues of control and exposed rats at PND 40 indicating recovery from lead-induced oxidative stress. This research work was presented as a poster in Annual Biomedical Research Conference for Minority Students (ABRCMS) at Dallas, Texas, USA, during November 10–13, 2004 and the abstract was printed on page 231 of the Conference Proceedings     

Region specific increase in the antioxidant enzymes and lipid peroxidation products in the brain of rats exposed to lead

The objective of this study is to determine the effect of lead (pb) on antioxidant enzymes and lipid peroxidation products in different regions of rat brain. Wistar male rats were treated with lead acetate (500 ppm) through drinking water for a period of 8 weeks. Control animals were maintained on sodium acetate. Treated and control rats were sacrificed at intervals of 1st, 4th and 8th week and the whole brains were dissected on ice into four regions namely the cerebellum, the hippocampus, the frontal cortex and the brain stem. Antioxidant enzymes namely catalase and superoxide dismutase in all the four regions of brain were determined. In addition, lipid peroxidation products were also estimated. The results indicated a gradual increase in the activity of antioxidant enzymes in different regions of the brain and this response was time-dependent. However, the increase was more in the cerebellum and the hippocampus compared to other regions of the brain. The lipid peroxidation products also showed a similar trend suggesting increased effect of lead in these two regions of the brain. The data indicated a region-specific oxidative stress in the brain exposed to lead.     

Ontogenic characteristics of changes in fatty acid composition of the liver lipids as a main substrate for peroxidation in geese

Dynamics of fatty acid composition of geese liver lipids in embryogenesis and early postnatal period has been investigated. High nonsaturation of these tissues lipids is shown during all the period of researches. It is established, that in the second half of embryogenesis and in the beginning of postnatal period (first two weeks) the increase of oleic acid contents is observed with simultaneous decrease of the contents of the polynonsaturated fatty acids (PUFA) showing properties of endogenous bioregulators (arachidonic acid (AA), docosahexaenoic acid [figure: see text] (DHA). From the two-weeks age of gosling the contents of the mentioned acids changes in the opposite direction. The coordination of dynamics of TBA-active products with nonsaturation of fatty acids (FA) expressed in mEqu/g concerning double bonds, and also with respect to AA/DHA has been revealed.     

Sex-dependent antioxidant enzyme activities and lipid peroxidation in ageing mouse brain

We investigated whether oxidant status and antioxidant enzyme activities during ageing of mouse brain are regulated in sex-dependent manner. In the homogenate from the brain of 1, 4, 10 and 18 months old male and female CBA mice, lipid peroxidation (LPO), total superoxide dismutase (tSOD), catalase (CAT) and glutathione peroxidase (Gpx) were determined. LPO was age- and sex-related, favoring males over females throughout the lifespan with the peak in both sexes at 10 months of age. Throughout ageing, no difference in tSOD activity between male and female brains was observed, except in immature 1 month old mice. Gender-related difference in Gpx activity was observed, with higher level in females comparing to males, reaching statistical significance in senescent (18 months old) animals. CAT activity was drastically changed with ageing in both the male and female brain. We found different age associated trends in CAT activity in males and females: decreased with age in males and increased with age in females. Taken together, the present findings indicate that brains of female mice have lower oxidant and higher antioxidant capacity mostly related to CAT and to a lesser extent to Gpx activity.     

Effect of cigarette smoke on lipid peroxidation and antioxidant enzymes in albino rat

Effect of cigarette smoke on lipid peroxidation (LPX) and antioxidant enzymes like catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and glutathione-S-transferase (GST) in various organs like brain, heart, lung, liver and kidney of the albino rats exposed to cigarette smoke for 30 min/day for a period of 30 days were assayed. It was observed that the lipid peroxide levels in liver, lung and kidney were enhanced in case of animals exposed to cigarette smoke, whereas brain and heart did not show any change as compared to control animals. The activity of the antioxidant enzymes was also elevated in liver, lung and kidney of the test animals whereas, brain and heart did not show any change in the activities of all of these antioxidant enzymes except glutathione-s-transferase which was increased in brain also. The level of reduced glutathione (GSH) was lowered in liver, lung and kidney of the tested animals when compared with the control animals but there was no significant change in brain and heart. The results of our study suggest that cigarette smoke induces lipid peroxidation in liver, lung and kidney, and the antioxidant enzymes levels were enhanced in order to protect these tissues against the deleterious effect of the oxygen derived free radicals. The depletion of reduced glutathione in these organs could be due to it's utilization by the tissues to mop off the free radicals.     

Hepatic antioxidant enzymes and lipid peroxidation in carbon tetrachloride-induced liver cirrhosis in rats

Liver cirrhosis was induced in rats by the combined action of oral phenobarbitone and inhalations of carbon tetrachloride vapors. These rats manifested hepatosplenomegaly, hypoalbuminemia, and 2- to 17-fold elevations in serum transaminases and alkaline phosphatase levels. The hepatic antioxidant enzymes, superoxide dismutase and catalase, showed 28 and 60% decreases, respectively. There was, however, no increase in the hepatic lipid peroxidation. These studies suggest that in cirrhosis liver cell damage may result due to the direct attack of the oxygen free radicals. Lipid peroxidation in the liver may not be a prerequisite for the development of cirrhosis, as is generally believed.     

Effect of cadmium on lipid peroxidation and activities of antioxidant enzymes in growing pigs

Malondialdehyde (MDA), glutathione (GSH) content, total antioxidant capacity (T-AOC) levels, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione transferase (GST) activities were studied in serum, liver, and kidney of growing pigs after graded doses of cadmium administration in diets. One hundred ninety-two barrows (Duroc x Landrace x Yorkshire), with similar initial body weight 27.67±1.33 kg, were randomly allotted into 4 different treatments with 3 replications (16 pigs per replication). The treatments received the same basal diet added with 0, 0.5, 5.0, and 10.0 mg/kg cadmium (as CdCl₂), respectively. The results showed pigs treated with 10 mg/kg cadmium significantly decreased average daily gain (ADG) (p<0.05) and increased feed/gain ratio (F/G) (p<0.05) compared to the control. In this treatment, the contents of MDA increased significantly (p<0.05), GSH concentrations, T-AOC levels, and the activities of SOD, GSH-PX, and GST decreased significantly (p<0.05). The results indicate 10 mg/kg cadmium could decrease pig antioxidant capacity after extended exposure and cadmium-induced increase lipid peroxidation might not be only the result of the possibility of lower level of GSH but could also be as a result of direct action of cadmium on peroxidation reaction.     

Aging and lung antioxidant enzymes, glutathione, and lipid peroxidation in the rat.

The five major antioxidants enzymes, cytochrome oxidase (COX), GSH, and GSSG, and endogenous and in vitro stimulated lipid peroxidation (TBA-RS) were assayed in the lung of old (28 months) and young (9 months) adult rats due to the almost total absence of data of this kind in this tissue, which is normally exposed to relatively high pO2 throughout life. Catalase, selenium (Se)-dependent GSH peroxidase (GPx), GSH reductase, GSH, GSSG, GSSG/GSH, and in vivo and in vitro TBA-RS showed similar values in old and young animals. The decrease observed for non Se-dependent GPx disappeared when the values were expressed in relation to COX activity. Only superoxide dismutase showed a clear decrease when referred both to protein and COX activity. These results suggest that lung aging is not accelerated in old age due to a decrease in the antioxidant capacity of the tissue. Nevertheless, they are compatible with a continuous damage of the lung tissue by free radicals throughout the life span.     

Changes in the activity of antioxidant enzymes and level of lipid peroxidation in the embryo brain tissue during prenatal action of ethanol]

Catalase, superoxide dismutase (SOD) activity and level of lipid peroxidation in embryo brain of 13-17-th day were evaluated during ethanol consumption by pregnant rats. The level of lipid peroxidation was more higher in alcohol groups, than in control groups. At the same time the reduced glutathione content was decreased by 13% in the brain of 15-th day embryos under the same conditions. One can draw a conclusion that the elevated level of lipid peroxidation may be a consequence of activated free radical mechanisms or consequence of reduced activity of a non-enzymatic antioxidant system.     

Modulations by dietary restriction on antioxidant enzymes and lipid peroxidation in developing mice.

The effects of dietary restriction (DR) on the activities of liver superoxide dismutase (SOD), catalase (Cat), and glutathione peroxidase (GPX) and the level of lipid peroxidation (LP) in developing mice were investigated in this study. Male and female Kunmin mice were fed a standard rodent diet ad libitum (AL), 80% of AL food intake (20% DR), or 65% of AL food intake (35% DR) for 12 or 24 wk. Both 12 and 24 wk of DR resulted in retarded body weight gain in male and female mice. The activities of SOD, Cat, and GPX and the content of LP in DR male and female mice were not different (P > 0.05) from those in controls after 12 wk of DR. However, the SOD activity was increased at 24 wk in 20% DR (P < 0.05) and 35% DR (P < 0.01) male, but not in DR female, mice. The Cat activity was elevated at 24 wk in both DR male (P < 0.05 for 20% DR, P < 0.01 for 35% DR) and female (P < 0.01) mice with a greater increase in DR female (P < 0.05) than in DR male animals. GPX activity was also increased at 24 wk in DR male (P < 0.01) and female (P < 0.01) mice with a greater elevation in DR females (P < 0.05) than in DR males. Furthermore, LP was decreased at 24 wk in both DR male (P < 0.01) and female (P < 0.01) animals with a greater reduction in DR females (P < 0.01) compared with DR males. These findings indicated that 24 wk, but not 12 wk, of DR led to differential effects on liver SOD, Cat, and GPX activities and LP content in male and female mice during development, suggesting sex-associated modulations of DR on antioxidant systems in developing animals.     

Paraquat pre-treatment increases activities of antioxidant enzymes and reduces lipid peroxidation in salt-stressed cucumber leaves

To investigate whether paraquat (PQ) is involved in regulation of antioxidant enzymes and lipid peroxidation under short-term salt stress, and to elucidate the physiological mechanism of salt stress mitigated by PQ, a cucumber cultivar (cv. Chunguang no. 2) was exposed to 100 mM NaCl for 48 h after pre-treatment with 10 μM PQ for 1 h. When compared to the control, salt stress increased the levels of malonaldehyde (MDA), superoxide radical (O₂^·−) and hydrogen peroxide (H₂O₂) and the activities of antioxidant enzymes, such as superoxide dismutase (EC 1.15.1.1), ascorbate peroxidase (EC 1.11.1.11) and glutathione reductase (EC 1.6.4.2) in the cucumber leaves. Under salt conditions, PQ pre-treatment prevented oxidative stress as observed by the decreases in MDA, H₂O₂ and O₂^·− that correlated with the increase in antioxidant defenses. We propose that, at low concentrations, the PQ pre-treatment can reduce the salt-induced oxidative damage by increasing the antioxidative mechanisms in cucumber plants.     

Age-dependent variations in mitochondrial and cytosolic antioxidant enzymes and lipid peroxidation in different regions of central nervous system of guinea pigs

The age-related changes in the activities of antioxidant enzymes of mitochondrial and cytosolic fractions were measured in different regions of the central nervous system (CNS) in 10 and 32 months old guinea pigs. In old animals, the activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) were reduced (p < 0.05) in all the regions of CNS studied but catalase (CAT) declined significantly only in the cerebral cortex, hypothalamus and cerebellum. Glutathione reductase (GRd) activity declined in cerebral cortex and hypothalamus in the cytosolic fractions and only in cerebellum in the mitochondrial fraction. It is concluded that age-related decline in the activities of antioxidant enzymes is both region and enzyme specific. The endogenous lipid peroxide was found to be significantly higher (p < 0.05) in the 32 month old animals whereas, lipid peroxidation after incubating the tissue homogenate in air was found to be lower (p < 0.05). The in vitro mitochondrial lipid peroxidation decreased with age. The results indicate that accumulation of lipid peroxides takes place with ageing but the susceptibility of lipid peroxidation decreases in the older animals.     

Lipid peroxidation and antioxidant enzymes in vanadate-treated rats

Male Wistar rats received an aqueous solution of ammonium metavanadate (AMV) of 0.15 mg/V/ml concentration instead of water for 14 days. The erythrocyte count and haemoglobin level in blood were not changed; the haematocrit index was slightly increased. The spontaneous lipid peroxidation in kidney and liver homogenates was increased. The Fe(II)- or ascorbate-induced lipid peroxidation was more pronounced in the kidney than in the liver. No changes in lipid peroxidation were observed in erythrocytes after AMV treatment. The AMV treatment resulted in a decrease in the activity of the antioxidant enzymes, catalase and glutathione peroxidase in the kidney and liver; the cytosolic Cu,Zn-SOD and mitochondrial Mn-SOD were unchanged. The activity of the enzymes in blood was not changed. The results are discussed with a view to the participation of lipid peroxidation in vanadium toxicity.     

Effect of amiodarone (AMD) on the antioxidant enzymes,lipid peroxidation and mitochondrial metabolism

The effects of amiodarone (AMD) on lipid peroxidation of rat liver mitochondria, the formation of superoxide anions at the respiratory chain level, and the cytosolic and mitochondrial enzymatic protective mechanisms of oxidative stress were studied. An attempt to classify AMD according to its toxic ability to interfere with the integrated function of electron transport enzymes was also investigated. The results confirm the effects of AMD on complex I and permit the placing of this drug in class A of the classification of Knobeloch, together with rotenone, amytal and chaotropic agents. AMD has no effect on the activity of the enzymes superoxide dismutase, catalase, glutathione reductase and glutathione peroxidase, nor on glucose 6-phosphate dehydrogenase. AMD did not promote an increase in the formation of anion superoxide at the respiratory chain level. Pre-incubation with AMD (16·6 μM ) inhibited about 70 per cent of lipid peroxidation. The results suggest a protective effect of AMD against lipid peroxidation in mitochondrial membranes by iron-dependent systems. © 1997 John Wiley & Sons, Ltd.     

Effect of sulfite on antioxidant enzymes and lipid peroxidation in normal and sulfite oxidase-deficient rat erythrocytes

Sulfite and related chemical such as sulfite salts and sulfur dioxide has been used as a preservative in food and drugs. This molecule has also been generated from the catabolism of sulfur-containing amino acids. Sulfite is a very reactive and potentially toxic molecule and has to be detoxified by the enzyme sulfite oxidase (SOX). The aim of this study was to investigate the effects of ingested sulfite on erythrocyte antioxidant status by measuring glucose-6-phosphate dehydrogenase (G-6-PD), superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) activities and oxidant status by measuring thiobarbituric acid reactive substances (TBARS) in normal and SOX-deficient rats. Rats were assigned to four groups (n = 10 rats/group) as follows; control (C), sulfite (CS), deficient (D), and deficient + sulfite (DS). SOX deficiency was established by feeding rats a low molybdenum diet and adding to their drinking water 200 ppm tungsten (W). Sulfite (25 mg/kg) was administered to the animals via their drinking water. At the end of 6 weeks, Erythrocyte G-6-PD, SOD, and GPx but not CAT activities were found to be significantly increased with and without sulfite treatment in SOX-deficient groups. Sulfite treatment alone was also significantly increased erythrocytes’ SOD activity in CS group compared to control. TBARS levels were found to be significantly increased in CS and DS groups and decreased in D group. When SOX-deficient rats treated with sulfite, TBARS level was still higher than other groups. In conclusion, these results suggested that erythrocyte antioxidant capacity, a defense mechanism against the oxidative challenge, increased by endogenous and exogenous sulfite due to its oxidant nature. This increase was also observed in CS and DS groups but it was insufficient to prevent lipid peroxidation.     

CO2浓度倍增对城市银杏(Ginkgo biloba)叶片膜脂过氧化与抗氧化酶活性的影响

以生长在沈阳市区内的银杏为试材,使用开顶箱模拟法对倍增CO2浓度（700μmolmol-1）和正常空气CO2浓度（≈350μmolmol-1）条件下银杏生长参数,超氧阴离子自由基（O2^-.）产生速率,丙二醛（MDA）含量,抗坏血酸（ASA）含量,超氧化物歧化酶（SOD）、抗坏血酸过氧化物酶（APX）及谷胱甘肽还原酶（GR）活性动态变化进行分析,探讨高浓度CO2对银杏膜脂过氧化与抗氧化酶活性的影响。结果表明,在短期（60d）内CO2浓度倍增使银杏细胞内O2^-.产生速率与H2O2含量减少,而ASA含量与SOD、APX、GR活性升高。与对照相比,大多数测定显示出显著差别。但较长期（70d以上）CO2浓度倍增处理则使试验结果发生逆转,活性氧O2-.产生速率略有升高,SOD、APX、GR活性略有下降,ASA含量仍略高于对照（但与对照相比差异并不显著）,长期CO2浓度倍增处理可能使试验结果发生逆转。     

Activity of antioxidant system enzymes and lipid peroxidation product content in the liver and thymus of rats in the early stages of irradiation]

The activity of enzymes of the antioxidation system and the content of some lipid peroxidation products in the liver and thymus of irradiated (0.21 C/kg) rats have been investigated. Glutathione reductase and glutathione transferase activity in the liver and thymus of rats decreased during the first 24 h after irradiation. There was a phase change in the catalase activity during the initial postirradiation period. The content of malonic dialdehyde increased immediately after irradiation and somewhat decreased during the first 24 h. In 24 h, there observed a radiation-induced increase in the diene conjugate content in the liver and thymus of rats, against the background of low activity of such antioxidation system enzymes as glutathione transferase, glutathione reductase and catalase.     

Effect of cryopreservation on sperm parameters, lipid peroxidation and antioxidant enzymes activity in fowl semen

The aim of the present study was to determine the influence of chicken semen cryopreservation on sperm parameters, lipid peroxidation and antioxidant enzymes activities. Pooled semen from 10 Black Minorca roosters was used in the study. Semen samples were subjected to cryopreservation using the “pellet” method and dimethylacetamide (DMA) as a cryoprotectant. In the fresh and the frozen-thawed semen sperm membrane integrity (SYBR-14/propidium iodide (PI)), acrosomal damage (PNA-Alexa Fluor^®488) and mitochondrial activity (Rhodamine 123) were assessed using flow cytometry. Malondialdehyde (MDA) concentration, catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase (SOD) activities were determined in sperm cells and seminal plasma by spectrophotometry. All sperm characteristics evaluated using flow cytometry were affected by cryopreservation. After freezing-thawing, there was significant (P < 0.01) reduction in sperm membrane integrity, sperm acrosome integrity and mitochondrial activity. Following cryopreservation, MDA concentration significantly increased in chicken seminal plasma and spermatozoa (P < 0.01, P < 0.05). The CAT activity in seminal plasma significantly decreased (P < 0.05), while intracellular activity of this enzyme did not significantly change in frozen-thawed semen. In seminal plasma of frozen-thawed semen the significant increase (P < 0.01) in GPx activity was detected. Whereas GPx activity in spermatozoa remained statistically unchanged after thawing. The SOD activity significantly increased (P < 0.01) in cryopreserved seminal plasma with simultaneous decrease (P < 0.01) of its activity in cells. In conclusion, this is probably the first report describing the level of antioxidant enzymes in frozen-thawed avian semen. The present study showed that the activity of CAT, GPx and SOD in chicken semen was affected by cryopreservation, what increased the intensity of lipid peroxidation (LPO). Catalase appeared to play an important role in the sperm antioxidant defense strategy at cryopreservation since, opposite to SOD and GPx, its content was clearly reduced by the cryopreservation process. Change in the antioxidant defense status of the chicken spermatozoa and surrounding seminal plasma might affect the semen quality and sperm fertilizing ability.     

Tinospora cordifolia induces enzymes of carcinogen/drug metabolism and antioxidant system, and inhibits lipid peroxidation in mice

The present study is an effort to identify a potent chemopreventive agent against various diseases (including cancer) in which oxidative stress plays an important causative role. Here, we investigated the effect of a hydroalcoholic (80% ethanol: 20% distilled water) extract of aerial roots of Tinospora cordifolia (50 and 100mg/kg body wt./day for 2 weeks) on carcinogen/drug metabolizing phase-I and phase-II enzymes, antioxidant enzymes, glutathione (GSH) content, lactate dehydrogenase and lipid peroxidation in liver of 8-week-old Swiss albino mice. The modulatory effect of the extract was also examined on extrahepatic organs, i.e., lung, kidney and forestomach, for the activities of GSH S-transferase (GST), DT-diaphorase (DTD), superoxide dismutase (SOD) and catalase. Significant increases in the levels of acid-soluble sulfhydryl (-SH) and cytochrome P(450) contents, and enzyme activities of cytochrome P(450) reductase, cytochrome b(5) reductase, GST, DTD, SOD, catalase, GSH peroxidase (GPX) and GSH reductase (GR) were observed in the liver. Both treated groups showed decreased malondialdehyde (MDA) formation. In lung SOD, catalase and GST; in kidney SOD and catalase; and in forestomach SOD, DTD and GST showed significant increase at both dose levels of treatment. BHA (0.75%, w/w in diet), a pure antioxidant compound, was used as a positive control. This group showed increase in hepatic levels of GSH content, cytochrome b(5), DTD, GST, GR and catalase, whereas MDA formation was inhibited significantly. In the BHA-treated group, the lung and kidney showed increased levels of catalase, DTD and GST, whereas SOD was significantly increased in the kidney and forestomach; the latter also showed an increase in the activities of DTD and GST. The enhanced GSH level and enzyme activities involved in xenobiotic metabolism and maintaining antioxidant status of cells are suggestive of a chemopreventive efficacy of T. cordifolia against chemotoxicity, including carcinogenicity, which warrants further investigation of active principle (s) present in the extract responsible for the observed effects employing various carcinogenesis models.