Protective effects of whey on rat liver damage induced by chronic alcohol intake.

In 2012, alcohol liver disease resulted in 3.3 million-5.9% of global deaths. This study introduced whey protection capacity against chronic alcohol-induced liver injury. Rats were orally administered to 12% ethanol solution in water (ad libitum, average 8.14 g of ethanol/kg body weight (b.w.)/day) alone or combined with whey ( per os, 2 g/kg b.w./day). After 6-week treatment, chronic ethanol consumption induced significant histopathological liver changes: congestion, central vein dilation, hepatic portal vein branch dilation, Kupffer cells hyperplasia, fatty liver changes, and hepatocytes focal necrosis. Ethanol significantly increased liver catalase activity and glutathione reductase protein expression without significant effects on antioxidative enzymes: glutathione peroxidase (GPx), copper-zinc-containing superoxide dismutase (CuZnSOD) and manganese-containing superoxide dismutase (MnSOD). Co-treatment with whey significantly attenuated pathohistological changes induced by ethanol ingestion and increased GSH-Px and nuclear factor kappa B (NF-κB) protein expression. Our results showed positive effects of whey on liver chronically exposed to ethanol, which seem to be associated with NF-κB-GPx signaling.

Tianeptine's effects on spontaneous and Ca2+-induced uterine smooth muscle contraction.

Tianeptine is a novel anti-depressant with an efficacy equivalent to that of classical anti-depressants. Additional beneficial effects include neuroprotection, anti-stress and anti-ulcer properties whose molecular mechanisms are still not completely understood but may involve changes in the anti-oxidant defence system. Herein, we have studied the effects of tianeptine on both contractile activity of isolated rat uteri and components of the endogenous anti-oxidative defence system. Tianeptine-induced dose-dependent inhibition of both spontaneous and Ca2+-induced contraction of uterine smooth muscle. The effect was more pronounced in the latter. Tianeptine treatment increased glutathione peroxidase (GSH-Px) and catalase (CAT) activities in spontaneous and Ca2+-stimulated uteri. A significant decrease in glutathione-reductase (GR) activity in both spontaneous and Ca2+-induced uterine contractions after tianeptine treatment indicated a reduction in reduced glutathione and consequently a shift toward a more oxidised state in the treated uteri. In spontaneously contracting uteri, tianeptine caused a decrease in copper-zinc SOD (CuZnSOD) activity. Tianeptine's anti-depressant effects may be accomplished by triggering a cascade of cellular adaptations including inhibition of smooth muscle contractility and an adequate anti-oxidative protection response.

Expression analysis of genes involved in apoptosis, proliferation and endoplasmic reticulum stress in ionomycin/PMA treated Jurkat cells.

PURPOSE: Activation of T cells by direct stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Io) results in numerous downstream signals that activate pathways enabling T cells to proliferate and produce cytokines. Inducible T cell activation is regulated predominantly at the transcriptional level. Therefore, we were interested to analyze the transcriptional activity of the 19 genes involved in the regulation of several important cellular processes. METHODS: Quantitative real-time (RT) PCR analysis was performed using mRNA-specific primers and SybrGreen for relative mRNA expression levels of all the examined genes. RESULTS: Our results showed c-kit expression in Jurkat cells, further confirmed by sequencing of c-kit mRNAspecific PCR product. The expected increased expression of interleukin (IL)-2 mRNA, together with moderate Ki-67 upregulation, indicate the proliferation of PMA/Io treated Jurkat cells. Significant upregulation of nuclear factor (NF)-κB, JNK and the prosurvival Bcl-2 was followed by activation of only one protein kinase RNA-like endoplasmic reticulum kinase (PERK) out of 3 main endoplasmic reticulum (ER) stress subpathways (ATF6 and spliced XBP were downregulated). NF-κB and JNK activation, as well as ERK downregulation were reactive oxygen species (ROS)-independent, shown by the lack of activation of antioxidative enzymes (SOD, NOS, GSTP1, gGCS and GR). C-kit was downregulated in the absence of exogenous SCF (c-kit ligand). CONCLUSION: Based on these data it is concluded that the PMA/Io treatment of Jurkat cells induced increased expression of IL-2, followed by upregulation of prosurvival genes belonging to the Bcl-2 family. Neither c-kit nor the antioxidative system were activated, excluding their role in Jurkat T-cell activation in the absence of exogenous c-kit ligand SCF.

Hydrogen peroxide affects contractile activity and anti-oxidant enzymes in rat uterus.

BACKGROUND AND PURPOSE: The effects of hydrogen peroxide (H(2)O(2)) on uterine smooth muscle are not well studied. We have investigated the effect and the mechanism of action of exogenous hydrogen peroxide on rat uteri contractile activity [spontaneous and calcium ion (Ca(2+))-induced] and the effect of such treatment on anti-oxidative enzyme activities. EXPERIMENTAL APPROACH: Uteri were isolated from virgin Wistar rats and suspended in an organ bath. Uteri were allowed to contract spontaneously or in the presence of Ca(2+) (6 mM) and treated with H(2)O(2) (2 microM-3 mM) over 2 h. Anti-oxidative enzyme activities (manganese superoxide dismutase-MnSOD, copper-zinc superoxide dismutase-CuZnSOD, catalase-CAT, glutathione peroxidase-GSHPx and glutathione reductase-GR) in H(2)O(2)-treated uteri were compared with those in uteri immediately frozen after isolation or undergoing spontaneous or Ca(2+)-induced contractions, without treatment with H(2)O(2). The effect of inhibitors (propranolol, methylene blue, L-NAME, tetraethylamonium, glibenclamide and 4-aminopyridine) on H(2)O(2)-mediated relaxation was explored. KEY RESULTS: H(2)O(2) caused concentration-dependent relaxation of both spontaneous and Ca(2+)-induced uterine contractions. After H(2)O(2) treatment, GSHPx and MnSOD activities were increased, while CuZnSOD and GR (In Ca(2+)-induced rat uteri) were decreased. N(omega)-nitro-L-arginine methyl ester antagonized the effect of H(2)O(2) on Ca(2+)-induced contractions. H(2)O(2)-induced relaxation was not affected by propranolol, potentiated by methylene blue and antagonized by tetraethylamonium, 4-aminopyridine and glibenclamide, with the last compound being the least effective. CONCLUSIONS AND IMPLICATIONS: H(2)O(2) induced dose-dependent relaxation of isolated rat uteri mainly via changes in voltage-dependent potassium channels. Decreasing generation of reactive oxygen species by stimulation of anti-oxidative pathways may lead to new approaches to the management of dysfunctional uteri.

Antioxidant defense in mitochondria during diapause and postdiapause development of European corn borer (Ostrinia nubilalis, Hubn.).

Antioxidant enzymes (CAT, catalase; GPx, selenium nondependent glutathione peroxidase; GST, glutathione-S-transferase; GR, glutathione reductase; DHAR, dehydroascorbate reductase) were determined in the mitochondria of diapausing and non-diapausing larvae and pupae of both diapausing and non-diapausing larvae of the European corn borer (Ostrinia nubilalis, Hubn., Lepidoptera: Pyralidae). CAT, GST, and DHAR activity in mitochondria of diapausing larvae were reduced compared to non-diapausing larvae. Pupae of diapaused-larvae possessed lower GST, but higher DHAR activities compared to pupae of non-diapaused individuals. Comparison between larvae and pupae revealed lower GPx activity in the mitochondria of pupae. CAT activity in the mitochondria of pupae was higher compared to diapausing larvae, but lower than in non-diapausing ones. Correlation and canonical discriminant analyses revealed different antioxidant enzyme compositions for a particular stage and developmental pattern. Our results show that antioxidant enzymes have a similar role in the regulation of energetics in mitochondria as that in diapause and metamorphosis.

The anti-oxidative defence system in the isolated rat uterus during spontaneous rhythmic activity.

Possible interactions between nitric oxide donors, reactive oxygen species and anti-oxidative defence enzymes led us to determine the activities of anti-oxidative defence enzymes in isolated uterine smooth muscle before and after spontaneous rhythmic activity ex vivo. For our experiments we used isolated uteri from female Wistar rats. Our results showed an increase in total superoxide dismutase (SOD) and Mn SOD activities in uterine smooth muscle after spontaneous contractions when compared with nonexercised uterine smooth muscle. The activity of catalase (CAT) and glutathione preoxidase (GSH-Px) were also increased. No statistically significant changes in the activities of glutathione reductase (GR) and CuZn SOD were found. It is known that an organism's anti-oxidative defence system (guarding against excessive reactive oxygen species generation) requires balanced increments in its individual anti-oxidative enzyme activities rather than increases in the activity of only some enzymes without increases in others. Thus, we may conclude that some adaptive responses are found in exercised uterine smooth muscle but are not complete. Therefore, our results indicate that changes in anti-oxidative enzyme activities may influence the results of the examination of substances ex vivo.

Effect of thyroxine on antioxidant defense system in the liver of different aged rats.

The effects of altered thyroid state on the antioxidant defense system in the liver of differently aged rats were examined. Male rats aged 15, 45 and 75 days were treated with L-thyroxine, T(4) (40 microg/100 g body mass, s.c., one dose per day) for 14 days (finally aged 30, 60 and 90 days, respectively). The following antioxidant defense enzymes were measured: superoxide dismutases (both copper zinc, CuZn-SOD and manganese containing, Mn-SOD), catalase (CAT), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST), glutathione reductase (GR), as well as the content of low molecular mass antioxidant glutathione (GSH). The effect of T(4) on antioxidant defense system in the liver differs with respect to age. T(4) treatment decreased CAT and GST activities, as well as the content of GSH in animals aged 60 and 90 days. The same treatment elevated GR activity in rats at 30 days of age, this phenomenon was not observed in older animals. The different response of immature rats to thyroxine compared to older animals could be attributed to the differences in thyroxine metabolism and the developmental pattern. Direct effect of T(4) on mature rats can be considered as a part of its overall catabolic action.

Role of antioxidant defense during different stages of preadult life cycle in European corn borer (Ostrinia nubilalis, Hubn.): Diapause and metamorphosis.

Antioxidant enzymes, total glutathione (GSH), and ascorbic acid (ASA) were determined in whole body homogenates of nondiapausing larvae, diapausing larvae during the diapausing period (October, December, and February), and in pupae emerged from both diapausing and nondiapausing larvae of the European corn borer (Ostrinia nubilalis, Hubn., Lepidoptera: Pyralidae). The activities of catalase, selenium nondependent glutathione peroxidase (GPx), and glutathione-S-transferase (GST), as well as the content of GSH and ASA, were found to vary throughout the larval diapause. Compared to diapausing larvae, nondiapausing larvae were higher in levels of catalase, GPx, GST, and dehydroascorbate reductase (DHAR) activity. GSH content was also increased. However, nondiapausing larvae contained less ASA than diapausing ones. Pupae had higher GPx and GST activity and an increased ASA content compared to larvae. The pupae emerged from nondiapausing larvae had higher GST, glutathione reductase (GR), and DHAR activities, but lower GPx activity and ASA content than those emerged from diapausing larvae. Correlation analysis revealed differences in the way the antioxidant level is equilibrated for a particular stage and developmental pattern. The results suggest that cellular antioxidants are involved in both the protection of cells and the regulation of redox levels during the pre-adult stages of Ostrinia nubilalis. Arch. Insect Biochem. Physiol. 55:79-89, 2004.

Activity of superoxide dismutase and catalase in the bean weevil (Acanthoscelides obtectus) selected for postponed senescence.

Relationship of superoxide dismutase and catalase activities and aging were tested using bean weevil lines selected for postponed senescence. The beetles of different age (young and old) and mating status (virgin and mated) from the extended longevity lines were compared with their counterparts derived from the short-lived lines for activities of SOD and catalase. The old beetles from the long-lived lines had statistically significant higher activity of SOD than their controls. Although we did not find a significant effect of catalase on longevity, beetles originating from both types of lines exhibited an increased catalase activity during mating processes. In addition, we did observe an increased activity of catalase in one-day-old beetles of the short-lived lines relative to the same-aged individuals of the long-lived lines.

Seasonal changes in the antioxidative defense in ground squirrels (Citellus citellus): possible role of GSH-Px.

As seasonal hibernators, ground squirrels decrease their body temperature to 7 degrees C and hibernate during the winter. Maintenance at 30 degrees C prevents seasonal changes of body temperature and animals remain euthermic and active. We measured selenium (Se)-dependent glutathione peroxidase (GSH-Px), as well as the activity of other antioxidative components such as superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), and glutathione-S-transferase (GST) and the amount of low-molecular-weight antioxidants glutathione (GSH), ascorbic acid (AsA), and vitamin E (vit E) in spring, summer, and winter in ground squirrels continuously kept at a temperature of 30 degrees C. We examined liver and interscapular brown adipose tissue (IBAT) as thermogenic tissues, as well as the brain and the kidneys. During the winter, we found a decrease in enzymatic activity and an increase in the level of low molecular antioxidants in all tissues. Correlation analysis revealed a similarity in the composition of antioxidative defense (AD) among the tissues examined. The results obtained clearly demonstrated numerous correlative expressions of antioxidative components in this experimental model, especially of GSH-Px, suggesting the complexity of the system responsible for the maintenance of physiological homeostasis.

Seasonal changes in the activity of antioxidative defense in the kidneys of the euthermic ground squirrel (Citellus citellus).

The aim of this work was to determine the activity of the antioxidant enzymes: superoxide dismutase (EC 1.15.1.1; SOD), catalase (EC 1.11.1.6; CAT), glutathione peroxidase (EC 1.11.1.9; GSH-Px), glutathione-S-transferase (EC 2.5.1.18; GST), glutathione reductase (EC 1.6.4.2; GR) and the low molecular mass antioxidants: ascorbic acid (ASA) and vitamin E (vit E) in the kidney of ground squirrels during circannual changes. Keeping the ground squirrel at the temperature of thermic neutrality (30 degrees C) provides a stable euthermic state during the whole year and thus any change is due to the circannual rhythm. The highest specific activity of all examined antioxidative defense enzymes in the kidney was found in the spring, when ground squirrels are seasonally the most active. In the summer, lower specific activity of GSH-Px as well as of SOD and CAT were noted and, when expressed per g wet mass, only a decrease in GSH-Px activity was recorded. In the kidney of ground squirrels kept at 30 degrees C, the lowest specific activity of all examined enzymes was found during the winter and, when expressed per g wet mass, only the SOD activity was lower than in the spring and summer. Higher amounts of vitamins C and E were found in the ground squirrel kidneys in the summer. The results obtained in this work demonstrate that circannual regulation of metabolic activity, which is inherent to seasonal hibernators, is also expressed at the level of antioxidative defense in the kidneys.

Glutathione peroxidase in amyotrophic lateral sclerosis: the effects of selenium supplementation.

The activity of glutathione peroxidase (GSH-Px) as well as the activities of other antioxidative enzymes: CuZn superoxide dismutase (CuZn SOD), catalase (CAT), glutathione reductase (GR) in erythrocytes, as well as the activity of plasma glutathione transferase (GST), and the plasma content of vitamins E and C were evaluated in 35 sporadic amyotrophic lateral sclerosis (sALS) patients. The results revealed significantly decreased activity of both GSH-Px and CuZn SOD in sALS patients compared with the control. These data showed that a disturbed oxidative/antioxidative balance in sALS patients exists not only in motoneurons but also in the blood. The effect of exogenously administered selenium (Se), antioxidants, amino acids, a Ca2+ channel blocker such as nimodipine, and their combination in Alsamin was evaluated by screening parameter levels after 9 weeks of treatment. Only the use of all components together enhanced the activity of GSH-Px and the amount of vitamin E in sALS patients. Judging by the results of clinical trials, this treatment slowed the course of the disease.

Seasonal variation in the antioxidant defense system of the brain of the ground squirrel (Citellus citellus) and response to low temperature compared with rat.

Seasonal variation in the activity of antioxidant enzymes (superoxide dismutase (EC 1.15.1.1.; SOD), catalase (EC 1.11.1.6; CAT), glutathione peroxidase (EC 1.11.1.9; GSH-Px), glutathione reductase (EC 1.6.4.2; GR), glutathione-S-transferase (EC 2.5.1.18; GST) and low-molecular-weight antioxidants: ascorbic acid (AsA), vitamin E (VIT E) and glutathione (CSH+GSSG) were examined in the brain of the ground squirrels (Citellus citellus) maintained at 30 degrees C during the whole year. The highest activity (per mg protein) of antioxidant defense (AD) enzymes was found in the spring and was much lower in the summer. A further decrease in activity of CAT, GSH-Px and GST was observed in the winter. The highest levels of AsA and glutathione were recorded in winter in comparison with spring and summer. AD system in the brain of the ground squirrel and rates (maintained at thermoneutrality) exposed to low temperature (4 degrees C) for 3, 6 or 24 hr during the summer was studied as well. Summer was chosen as a period of stable euthermia for ground squirrels and in thermoregulation similar to rats. Consumption of free fatty acid and glucose during the acute exposure to low temperature was found to be species specific. In the ground squirrel, an increase in the specific activities of SOD, after 3, 6 and 24 hr, CAT after 3 and 6 hr and GR after 6 hr of exposure to low temperature was detected. When activities were expressed in U/g wet mass, an increase of SOD after 3, 6 and 24 hr (P < 0.02, P < 0.02, P < 0.005) and CAT and GSH-Px 3 hr (P < 0.01) upon exposure to low temperature was observed. In the rats, no changes in the specific activities of these enzymes after exposure to low temperature were recorded and only an increase in GST activity (U/g wet mass) after 6 hr exposure was registered. Low-molecular-weight AD components in both animal species were unchanged upon short-term exposure to low temperature. The species-specific differences in brain AD between the rats and the ground squirrels after short exposure to low temperature may be ascribed to seasonal changes of the brain activity in the latter.

Activity of antioxidant defense enzymes and glutathione content in some tissues of the Belgrade (b/b) laboratory rat.

The activity of antioxidant defense (AD) enzymes--superoxide dismutase (SOD, EC 1.15.1.1.), catalase (CAT, EC 1.11.1.6.), glutathione peroxidase (GSH-Px, EC 1.11.1.9.), glutathione-S-transferase (GST, EC 2.5.1.18), glutathione reductase (GR, EC 1.6.4.2) and glutathione (GSH) content of the anemic Belgrade (b/b) laboratory rats--were measured and analyzed in liver, spleen, lung, heart, brain and testes in comparison with nonanemic controls. The activities of hepatic Mn SOD, CAT, GSH-Px and GST (P < 0.02, P < 0.01 and P < 0.005) were decreased in anemic, comparing with nonanemic animals, whereas the spleen CuZn SOD, Mn SOD, CAT and GSH-Px (P < 0.005, P < 0.02, P < 0.005 and P < 0.01) activities were increased. In the lung of anemic rats, Mn SOD, GSH-Px and GR (P < 0.005, P < 0.01, P < 0.05) activities were higher, whereas GST (P < 0.01) activity was lower in relation to nonanemic ones. In anemic rats, heart Mn SOD (P < 0.05) activity was increased, brain GSH-Px (P < 0.005) activity was lower, whereas GR (P < 0.02) activity was higher compared with nonanemic controls. CuZn SOD (P < 0.05) activity in the testes was elevated and GSH-Px (P < 0.05) reduced in anemic animals. GSH content was decreased in the liver (P < 0.01), lung and brain (P < 0.005) and increased in the spleen (P < 0.02) of anemic rats in relation to the controls. Our data suggest phenotype specific differences in the AD system of the Belgrade (b/b) rat tissues in comparison with nonanemic controls.

Effect of the Host Plant on the Antioxidative Defence in the Midgut of Lymantria dispar L. Caterpillars of Different Population Origins.

THE RESPONSES OF GYPSY MOTH LARVAE ORIGINATING FROM TWO POPULATIONS (OAK FOREST, LOCUST FOREST) TO FAVORABLE (OAK) AND UNFAVORABLE (LOCUST) HOST PLANTS WERE MONITORED AT THE LEVEL OF MIDGUT ANTIOXIDATIVE DEFENCE: the activities of superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), glutathione reductase (GR), glutathione peroxidase like ('GSH-Px like') and glutathione content (GSH). Short-term change of the diet (3 days) to locust leaves of the 5th instar larvae (oak population) provoked an increase in GST and 'GSH-Px like' activities as well as in the amount of GSH. On the contrary, transferring the gypsy moth larvae (locust population) to oak leaves was followed by a decrease in GST, 'GSH-Px like' activities, and in the amount of GSH. Feeding gypsy moth larvae from hatching on an unfavorable host plant such as locust, led to increases in GST and SOD activities and GSH content, as well as to a decrease in CAT activity in all instars studied (4th, 5th, 6th). The locust leaf diet caused changes in other components of antioxidative defence dependent on larval instar and population origin, a feature which could be ascribed to trophic adaptation of the gypsy moth to an unfavorable host plant.

Effect of long-term exposure to cold on the antioxidant defense system in the rat.

Catalase (CAT), glutathione peroxidase (GSH-Px), glutathione reductase (GR), and glutathione-S-transferase (GST) activities as well as glutathione (GSH), ascorbic acid (AsA), and vitamin E concentrations were analyzed in the blood, liver, brain, interscapular brown adipose tissue (IBAT), and small intestine of rats exposed to low environmental temperature (4 degrees C; 35, 75, and 105 d of exposure) and in controls of the same age exposed to an environmental temperature of 22 +/- 2 degrees C. Prolonged cold exposure resulted in an increase in GSH-Px in IBAT and in small intestine after 35, 75, and 105 d of exposure. Catalase activity in cold-exposed animals was higher in IBAT after 75 and 105 d of cold exposure. Glutathione reductase activity was greater in brain after 35 d, in liver after 75 d, and in IBAT after 105 d of exposure to low temperatures as compared to the controls. In contrast, GST activity was lower in liver and IBAT after 35 and 75 d of cold exposure. AsA and GSH (determined only 105 d after cold exposure) were markedly higher in IBAT, whereas plasma GSH was lower and plasma AsA was higher in cold-exposed animals. The observed changes in analysed components of the antioxidant defense system under conditions of prolonged exposure to low temperature suggest that a reorganization the activity of this system at the molecular level occurred. Although other studies indicate that a 21-d cold exposure is sufficient for adaptation of thermogenesis, the present study shows that in general, longer periods are required for the registration of the changes in the antioxidant defense system.