Gestational purple grape juice consumption does not change fetal ductus arteriosus constriction in Wistar rats.

Grape juice consumption may influence the early occurrence of ductal constriction during pregnancy, since the consumption of foods rich in polyphenols can be linked to the premature constriction of the ductus arteriosus. This study aimed to evaluate the effect of purple grape juice consumption during gestation on fetal ductus arteriosus closure, prostaglandin levels, and oxidative stress markers in Wistar rats. We divided 18 pregnant rats into four groups: a control group (C), a single-dose grape juice group (SDGJ), a two-dose grape juice group (TDGJ) of 7 µl/g body weight per day, and an indomethacin group (I). Blood was collected on gestational day (GD) 0, 14, and 20. Prostaglandin levels were measured, and the livers and hearts were removed from the mothers and fetuses for oxidative stress analysis; histology of the fetal ductus arteriosus was performed. Prostaglandin levels (pg/ml) at GD 20 were (C:1462.10 ± 314.61); (SDGJ:987.66 ± 86.25); (TDGJ:1290.00 ± 221.57), and (I:584.75 ± 46.77). Fetal ductus arteriosus closure occurred only in the indomethacin group. Lipid peroxidation evaluated through thiobarbituric acid reactive substances (nmol/mg protein) in maternal livers was lower in the grape juice groups (C: 4.11 ± 0.76 nmol/mg protein), (SDGJ: 2.34 ± 0.36), (TDGJ: 1.52 ± 0.18), and (I: 4.20 ± 0.76). Sulfhydryls (nmol/mg protein) were lower in the TDGJ group (C:763.59 ± 61.38 nmol/mg protein), (SDGJ:978.88 ± 158.81), (TDGJ:385.32 ± 86.78), and (I:727.72 ± 49.12). Also, superoxide dismutase activity (USOD/mg protein) was higher in fetal hearts in this group: (C:5.29 ± 0.33), (SDGJ:4.48 ± 0.47), (TDGJ:7.35 ± 0.43), and (I:6.00 ± 0.18). We conclude that grape juice consumption in pregnancy does not induce ductus arteriosus closure in the fetus and presented potential antioxidant effects.

Purple grape juice consumption during the gestation reduces acetylcholinesterase activity and oxidative stress levels provoked by high-fat diet in hippocampus from adult female rats descendants.

The enzyme acetylcholinesterase participates in the end of cholinergic transmission and it has been shown that its activity is increased in some diseases that affect the brain, including Alzheimer disease. The objective of this study was to investigate the effect of purple grape juice consumption with or without high-fat diet in the gestational and lactation period on acetylcholinesterase activity and oxidative stress parameters in the hippocampus of female descendants. During pregnancy and lactation, 40 female Wistar rats received a control diet or a high-fat diet, with half of them receiving grape juice. After lactation, the female descendants received water and control diet in ad libitum until euthanasia on the 120 postnatal day. Hippocampus from were removed for analysis of AChE activity, protein oxidation and lipid peroxidation. It was observed that high-fat diet consumption during the pregnancy increased the AChE activity and the grape juice reduced this activity in descendants. The same was observed in protein oxidation, the descendants from high-fat diet had significantly highest values, and grape juice decreased the levels. We conclude that dietary choices during pregnancy can alter the acetylcholinesterase levels and grape juice is an important alternative to improve this function in adulthood.

The effect of consumption of purple grape juice in the gestational period on oxidative stress parameters in Wistar rat foetuses.

This study aimed to evaluate the effects of purple grape juice consumption in pregnancy on oxidative stress parameters in Wistar rat fetuses. Twenty-four pregnant rats were divided into five groups: control group, indomethacin group (received a single dose of indomethacin in DG20), group grape juice DG14 (received an amount for 14 days/first and second gestational trim), group grape juice DG20 (received a dose throughout the gestational period), group grape juice two doses (received two doses, at morning and afternoon). On the 20th day of pregnancy (DG20), rats were anesthetized, and a cesarean section was performed to obtain the fetuses. A sample of liver, heart, and total brain of fetuses was collected for oxidative stress analyses. Values P<0.05 were considered significant. In fetuses' heart, we observed that the grape juice two dose group decreased sulfhydryl and increased SOD. In the liver, the grape juice decreased TBARS and SOD. There was a decrease in carbonyl and sulfhydryl in the indomethacin and grape juice one dose groups in the brain. We conclude that indomethacin altered oxidative stress parameters only in the fetal brain, and grape juice was presented as an important modulator of antioxidant capacity when consumed in a dose.

Effects of the ingestion of different kinds of white grape juice (Vitis labrusca) during adolescence on body weight, biochemical parameters and oxidative stress in liver of adult Wistar rats.

The objective of this study was to evaluate the effects of the ingestion of different white grape juices: organic, conventional and conventional grape juice with 5% lemon juice during adolescence on biochemical serum profile and oxidative stress level in liver of adult Wistar rats. The phenolic and vitamin C composition of the juices were evaluated. During 32 days the rats were treated with the juices or oral water (gavage) for at a dose of 7 µL/g body weight. The animals were divided into 4 groups (n = 16/each). In the end, half of the animals received an intraperitoneal CCl4 injection of 3.0 mL/kg; the other ones received mineral oil. After euthanasia, biochemical parameters were evaluated in serum and oxidative stress in the liver. It is possible to emphasize that the juices have different phenolic and vitamin C contents. The juice consumption didn't alter the weight body and biochemical parameters in adult life.

Chronic Exposure to ß-Alanine Generates Oxidative Stress and Alters Energy Metabolism in Cerebral Cortex and Cerebellum of Wistar Rats.

ß-Alanine occurs naturally in the human central nervous system and performs different functions. It can act as either a neurotransmitter or a neuromodulator, depletion of taurine levels and competitive antagonist of γ-aminobutyric acid (GABA). The ß-amino acid accumulation exerts an important biological function as delay in brain development, oxidative stress and disturbances in energy metabolism, characterized as an inborn error of metabolism classified as ß-alaninemia. We evaluated the effects of the chronic administration of ß-alanine on some parameters of oxidative stress and enzymes of energy metabolism in cerebral cortex and cerebellum of 21-day-old Wistar rats. The animals received peritoneal injections of ß-alanine (300 mg/kg of body weight), and the controls received the same volume (10 µl/g of body weight) of saline solution (NaCl 0.9%), twice a day at 12-h interval, from the 7th to the 21st postpartum day. We observed that ß-amino acid was able to increase the levels of reactive oxygen species (ROS) in the two tissues; however, only in cerebral cortex total content of sulfhydryl was increased. ROS are possibly acting on antioxidant enzymes glutathione peroxidase (GPx) (cerebral cortex and cerebellum) and superoxide dismutase (SOD) (cerebellum) inhibiting their activities. We also evaluated the activities of enzymes of the phosphoryl transfer network, where we observed an increase in hexokinase and cytosolic creatine kinase (Cy-CK) activities; however, it decreased glyceraldehyde 3-phosphate dehydrogenase (GAPDH), pyruvate kinase (PK) and lactate dehydrogenase (LDH) activities, in both tissues. Besides, the ß-alanine administration increased the activities of complex II, complex IV and succinate dehydrogenase (SDH). Those results suggest that the chronic administration of ß-alanine causes cellular oxidative damage, significantly changing the energy metabolism.

Maternal consumption of high-fat diet and grape juice modulates global histone H4 acetylation levels in offspring hippocampus: A preliminary study.

This study aimed to investigate the impact of maternal consumption of a hyperlipid diet and grape juice on global histone H4 acetylation levels in the offsprinǵs hippocampus at different stages of development. During pregnancy and lactation of offspring, dams were divided into 4 groups: control diet (CD), high-fat diet (HFD), control diet and purple grape juice (PGJCD) and purple grape juice and high-fat diet (PGJHFD). Male Wistar rats were euthanized at 21days of age (PN21, adolescents) and at 50days of age (PN50, adults). The maternal consumption of grape juice increased global histone H4 acetylation levels in hippocampus of adolescents pups (PN21), an indicative of enhanced transcriptional activity and increased gene expression. On the other hand, the maternal high-fat diet diminished significantly this epigenetic marker in the adult phase (PN50), suggesting gene silencing. These preliminary findings demonstrated that the maternal choices are able to induce changes on histone H4 acetylation status in hippocampus of the offspring, which may modulate the expression of specific genes. Interestingly, this response occurs in an age and stimuli-dependent manner and strongly reinforce the importance of maternal choices during gestation.

Method validation for determination of metals in Vitis labrusca L. grapevine leaf extracts by inductively coupled plasma mass spectrometry (ICP-MS).

Vitis labrusca L. is the main species used for wine and juice production in Brazil. The grapevine leaves can be used both as functional foods and as cheapest sources for the extraction of phenolic compounds. Besides the antioxidant activity, grapevine leaves exhibited significant anti-inflammatory activity. Therefore, the aim of this study was to develop and validate an analytical methodology to determine the metals selenium (96Se), chromium (53Cr), nickel (62Ni), cadmium (111Cd) and lead (206Pb) in 30 samples of grapevine leaf extracts (Vitis labrusca, Bordo cultivar) using inductively coupled plasma mass spectrometry (ICP-MS). To obtain the grapevine leaf extracts the samples were milled, weighed and digested in microwave oven with nitric acid. The method showed linearity, precision, accuracy and limits of quantification and detection acceptable for INMETRO protocol validation of analytical methods. Therefore, the method using ICP-MS was developed and validated to determine metals concentrations in grapevine leaves of Vitis labrusca L. and the proposed method could be applied in routine analytical laboratory.

Subchronic treatment with acai frozen pulp prevents the brain oxidative damage in rats with acute liver failure.

Acai has been used by the population due to its high nutritional value and its benefits to health, such as its antioxidant properties. The aim of this study was to evaluate the protective effect of acai frozen pulp on oxidative stress parameters in cerebral cortex, hippocampus and cerebellum of Wistar rats treated with carbon tetrachloride (CCl4). Thirty male Wistar rats (90-day-old) were orally treated with water or acai frozen pulp for 14 days (7 µL/g). On the 15th day, half of the animals received treatment with mineral oil and the other half with CCl4 (3.0 mL/kg). The cerebral cortex, hippocampus and cerebellum were dissected and used for analysis of creatine kinase activity (CK), thiobarbituric acid reactive substances (TBARS), carbonyl, sulfhydryl, and the activity of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). Statistical analysis was performed by ANOVA followed by Tukey's post-test. CCl4 was able to inhibit CK activity in all tissues tested and to provoke lipid damage in cerebral cortex and cerebellum, and protein damage in the three tissues tested. CCl4 enhanced CAT activity in the cerebral cortex, and inhibited CAT activity in the hippocampus and cerebellum and reduced SOD activity in all tissues studied. Acai frozen pulp prevented the inhibition of CK, TBARS, carbonyl and CAT activity in all brain structures and only in hippocampus for SOD activity. Therefore, acai frozen pulp has antioxidant properties and maybe could be useful in the treatment of some diseases that affect the central nervous system that are associated with oxidative damage.

Evaluation of antioxidant activity of grapevine leaves extracts (Vitis labrusca) in liver of Wistar rats.

The aim of this study was to evaluate the hepatoprotection of organic and conventional grapevine leaves extract (Vitis labrusca). The total polyphenol content and the isolate polyphenols by HPLC were evaluate. The animals received intraperitoneal injections of saline or extracts (conventional or organic - 30 mg/kg) for 14 days. On day 15, the rats received carbon tetrachloride (CCl4) or mineral oil (i.p.). After 4h, the animals were euthanized. The analysis of the liver enzymes activity (AST, ALT, GGT) was performed using serum, obtained by blood and the levels of lipid peroxidation (TBARS), protein oxidation (carbonyl), and the activity of antioxidant enzymes superoxide dismutase and catalase were analyzed in the liver. The results showed that the organic extract is richer in polyphenol and resveratrol than the conventional one. Both extracts prevent lipid peroxidation and protein oxidation generated by CCl4. Moreover, the extracts demonstrated ability to modulate the activity of SOD and CAT, as well as to establish a balance in the ratio of SOD/CAT. We also found that the CCl4 increased the levels of AST and GGT, and that both extracts prevent this. These results indicate that grapevine leaves extracts, both, organic and conventional, can prevent liver disorders.

Total Phenolic Content and Antioxidant Activity of Different Types of Chocolate, Milk, Semisweet, Dark, and Soy, in Cerebral Cortex, Hippocampus, and Cerebellum of Wistar Rats.

Chocolate is a product consumed worldwide and it stands out for presenting an important amount of phenolic compounds. In this study, the total phenolic content and antioxidant activity in the cerebral cortex, hippocampus, and cerebellum of male Wistar rats when consuming different types of chocolate, including milk, semisweet, dark, and soy, was evaluated. The total polyphenols concentration and antioxidant activity in vitro by the method of DPPH radical-scavenging test were evaluated in chocolate samples. Lipid peroxidation (TBARS), protein oxidation (carbonyl), sulfhydryl groups, and activity of SOD enzyme in cerebral cortex, hippocampus, and cerebellum of rats treated or not with hydrogen peroxide and/or chocolate were also evaluated. The dark chocolate demonstrated higher phenolic content and antioxidant activity, followed by semisweet, soy, and milk chocolates. The addition of chocolate in the diet of the rats reduced lipid peroxidation and protein oxidation caused by hydrogen peroxide. In the sulfhydryl assay, we observed that the levels of nonenzymatic defenses only increased with the chocolate treatments The SOD enzyme activity was modulated in the tissues treated with the chocolates. We observed in the samples of chocolate a significant polyphenol content and an important antioxidant activity; however, additional studies with different chocolates and other tissues are necessary to further such findings.

U18666A Treatment Results in Cholesterol Accumulation, Reduced Na(+), K(+)-ATPase Activity, and Increased Oxidative Stress in Rat Cortical Astrocytes.

The objective of this study was to determine the effect of U18666A, an inhibitor of cholesterol synthesis and its intracellular transport, on oxidative stress parameters in cortical astrocytes cultured from Wistar rats (0-3 days old). The cultures were incubated with U18666A (0.25 µg/mL) for 48 h, conditions that are considered ideal to mimic Niemann-Pick type C disease. A variety of indicators of oxidative stress were measured. U18666A treatment increased cholesterol 2-fold in treated compared to control astrocytes. Oxidative stress was significantly elevated in treated cells as demonstrated by a 1.7-fold increase in thiobarbituric acid reactive substances, a 60% decrease is sulfhydral groups, and a 3.7-fold increase in carbonyl groups, indicative of increased lipid and protein oxidation following U18666A treatment. Consistent with these changes, both catalase and superoxide dismutase activities were significantly reduced nearly 50% in treated compared to control astrocytes. Collectively, these change resulted in a 50% reduction in Na(+), K(+)-ATPase specific activity following U18666A treatment, suggesting a significant alteration in its plasma membrane environment. Overall, these changes indicate that U18666A treatment results in increased cholesterol levels and an increased level of oxidative stress in cortical astrocytes, consistent with what is observed in Niemann-Pick type C disease.

Carbon Tetrachloride Increases the Pro-inflammatory Cytokines Levels in Different Brain Areas of Wistar Rats: The Protective Effect of Acai Frozen Pulp.

Acai offers health benefits associated with its high antioxidante capacity, phytochemical composition, nutritional and sensory value. Therefore, the objective of this study was to evaluate the protective effect of acai frozen pulp on carbon tetrachloride (CCl4)-induced damage via modulation of anti- and pro-inflammatory cytokines in rat brain tissue. The rats were treated via oral (gavage) daily with water or acai frozen pulp for 14 days at a dose of 7 µL/g. On the 15th day, the animals in each group received a single intraperitoneal injection of CCl4 in a dose of 3.0 mL/kg or the same volume of mineral oil. After 4 h, the animals were euthanized by decapitation and the cerebral cortex, hippocampus and cerebellum were dissected and homogenated to evaluate the levels of tumor necrosis factor α (TNF-α), interleukin 1ß (IL-1ß), interleukin 18 (IL-18), interleukin 6 (IL-6) and interleukin 10 (IL-10). Data were statistically analyzed by analysis of variance followed by the Tukey post hoc test. It was observed that CCl4 increased TNF-α, IL-1ß and IL-18 levels in all brain tissues, and that acai frozen pulp was able to prevent this increase. IL-6 and IL-10 brain tissue levels remained unchanged during all treatments. CCl4 experimental model was suitable to investigate brain tissue anti and pro-inflammatory cytokines. Acai frozen pulp prevented an increase in IL-1ß, IL-18 and TNF-α, while IL-6 and IL-10 levels remained unchanged. The precise pathway by which inflammation contribute to hepatic encephalopathy, as well as to how this pathway can be modulated, is still under investigation.

Effects of concurrent training on oxidative stress and insulin resistance in obese individuals.

Obesity is associated with insulin resistance (IR) and increased oxidative stress. Thus, the present study aimed to evaluate anthropometric parameters, IR, and oxidative stress in obese individuals subjected to two types of concurrent training at the same intensity but differing in frequency. Accordingly, 25 individuals were divided into two groups: concurrent training 1 (CT1) (5 d/wk) and concurrent training 2 (CT2) (3 d/wk), both with moderate intensity. Anthropometric parameters, IR, and oxidative stress were analyzed before and after 26 sessions of training. Both groups had reduced body weight and body mass index (P < 0.05), but only CT1 showed lower body fat percentage and increased basal metabolic rate (P < 0.05). Moreover, CT1 had increased HOMA-IR and decreased protein damage (carbonyl level), and CT2 had decreased HOMA-IR and increased lipid peroxidation (TBARS level) (P < 0.05). On the other hand, both training protocols reduced the GPx activity. It can be concluded that both types of concurrent training could be an alternative for lowering body weight and BMI. Also, it was observed that concurrent training, depending on the frequency, can contribute to reducing body fat, oxidative damage (protein oxidation), and IR but can induce oxidative damage to lipids. More studies are needed to elucidate the mechanisms involved.

Creatine and pyruvate prevent the alterations caused by tyrosine on parameters of oxidative stress and enzyme activities of phosphoryltransfer network in cerebral cortex of Wistar rats.

Tyrosine accumulates in inborn errors of tyrosine catabolism, especially in tyrosinemia type II. In this disease caused by tyrosine aminotransferase deficiency, eyes, skin, and central nervous system disturbances are found. In the present study, we investigated the chronic effect of tyrosine methyl ester (TME) and/or creatine plus pyruvate on some parameters of oxidative stress and enzyme activities of phosphoryltransfer network in cerebral cortex homogenates of 21-day-old Wistar. Chronic administration of TME induced oxidative stress and altered the activities of adenylate kinase and mitochondrial and cytosolic creatine kinase. Total sulfhydryls content, GSH content, and GPx activity were significantly diminished, while DCFH oxidation, TBARS content, and SOD activity were significantly enhanced by TME. On the other hand, TME administration decreased the activity of CK from cytosolic and mitochondrial fractions but enhanced AK activity. In contrast, TME did not affect the carbonyl content and PK activity in cerebral cortex of rats. Co-administration of creatine plus pyruvate was effective in the prevention of alterations provoked by TME administration on the oxidative stress and the enzymes of phosphoryltransfer network, except in mitochondrial CK, AK, and SOD activities. These results indicate that chronic administration of TME may stimulate oxidative stress and alter the enzymes of phosphoryltransfer network in cerebral cortex of rats. In case this also occurs in the patients affected by these disorders, it may contribute, along with other mechanisms, to the neurological dysfunction of hypertyrosinemias, and creatine and pyruvate supplementation could be beneficial to the patients.

Oxidative stress parameters of Gaucher disease type I patients.

Enzymatic deficiency in Gaucher disease (GD) patients may induce a cascade of events, culminating in secondary effects such as the production of reactive oxygen species (ROS). Detoxification through biological systems which remove or repair the damage may cause the production of peroxides and free radicals that damage all cell components, including proteins, lipids and ADN. The study's aim was the test, using the analysis of plasma samples' the use of lipid peroxidation by thiobarbituric acid reactive substances (TBARS), protein damage by carbonyl assay, non-enzymatic antioxidant defenses by sulfhydryl (SH) content, antioxidant enzymatic defenses by catalase (CAT) and superoxide dismutase (SOD), from patients with GD type I patients who received no prior treatment. Blood samples were collected from 10 patients previously diagnosed with GD type I and from 11 healthy subjects. Chitotriosidase (CT) activity was measured in plasma and the activity of ß-glucosidase (GBA) was measured in leukocytes. The results showed a significant increased (p < 0.005) in GD samples when compared to healthy controls in CAT, SOD and SH, but there was no change in TBARS and carbonyl in the comparison between the two groups. In conclusion, the present data indicates the increased levels of enzymatic and non-enzymatic defenses without any effect on lipid peroxidation and damage to proteins. We believe that the results of this study are relevant to understanding the cellular changes involved in this important LSDs.

Assessment of changes in energy metabolism parameters provoked by carbon tetrachloride in Wistar rats and the protective effect of white grape juice.

The objective of this study was to evaluate the effect of organic and conventional grape juices consumption on the behavior of rats and their neuroprotective effect on the activity of brain energy metabolism enzymes in different brain areas of adult rats on the experimental model of hepatic encephalopathy. Male Wistar rats (90-days-old) were treated once a day with conventional or organic white grape juice by gavage for 14 days (7 µL/g). On the 15th day the rats received carbon tetrachloride (CCl4) in a single dose of 3.0 mL/kg. Cerebral cortex, hippocampus and cerebellum were dissected to measure the activity of creatine kinase (CK) and pyruvate kinase (PK). No changes in feeding behavior were observed after the treatment with the grapes juices. However, there was an increase in grooming behavior in the open field test provoked by both juices. CCl4 inhibited CK activity in cerebral cortex and hippocampus of the rats and CCl4 also reduced PK activity in all brain structures studied. Furthermore, both white grape juices prevented the decrease in the activity of CK and PK. Therefore, we can suggest that organic and conventional white grape juices could restore the activity of enzymes with a central role in brain energy metabolism.

Consumo exacerbado de lipídeos provoca dano celular em algumas doenças metabólicas e cardiovasculares / Excessive consumption of fat provokes systemic cellular damage in some metabolic and cardiovascular diseases

OBJECTIVE: To review the deleterious biochemical mechanisms related to changes of oxidative stress and inflammation, provoked by excessive consumption and accumulation of lipids in different tissues, in cardiovascular diseases, diabetes and metabolic syndrome. Data source: This review article was based on papers selected for their relevance from databases such as Science Direct, PubMed and SciELO, published between 1995 and 2014. The search included the following keywords: High-fat diet, obesity, oxidative stress, inflammation. Data synthesis: Evidence suggests that the deleterious effects of lipotoxicity are related to ectopic deposition, activation of lipolysis, formation of lipid metabolites, generation of reactive oxygen species and oxidative stress, as well as to stimulation of inflammatory cascades. In this context, the simultaneous activation of these biochemical mechanisms interferes with intracellular signaling cascades, disrupting homeostasis, leading to systemic cellular damage or even lipoapoptosis. CONCLUSIONS: The identification of the biochemical cellular pathways involved in the process provides an understanding of the molecular mechanisms and, especially, may identify potential therapeutic targets

OBJETIVO: Revisar mecanismos bioquímicos deletérios relacionados com alterações de estresse oxidativo e inflamação ocasionados pelo consumo excessivo e acúmulo de lipídeos em diferentes tecidos, nas doenças cardiovasculares, diabetes e síndrome metabólica. Fonte de dados: Este artigo de revisão baseou-se em artigos científicos, selecionados por sua relevância e provenientes de bases de dados como Science Direct, Scielo e Pubmed, publicados entre 1995 e 2014. A busca contemplou as seguintes palavras-chave: dieta hiperlipídica, obesidade, estresse oxidativo, inflamação. Síntese dos dados: Evidências sugerem que os efeitos deletérios da lipotoxidade estão relacionados com a deposição ectópica, ativação da lipólise, formação de metabólitos lipídicos, geração de espécies reativas e estresse oxidativo, bem como estimulação de cascatas inflamatórias. Nesse contexto, a ativação simultânea desses mecanismos bioquímicos interfere em cascatas de sinalização intracelular, prejudicando a homeostase, levando ao dano celular sistêmico ou até mesmo à lipoapoptose. CONCLUSÕES: A identificação das vias bioquímicas celulares envolvidas proporciona a compreensão dos mecanismos moleculares e, principalmente, pode identificar possíveis alvos terapêuticos

In vitro antioxidant capacity of tea of Echinodorus grandiforus, "leather hat," in Wistar rat liver.

Oxidative stress has been considered as one of the factors responsible for hepatic diseases, which sometimes require new ways of treatment. The present study aimed to evaluate the in vitro antioxidant capacity of the tea of Echinodorus grandiforus ("leather hat" plant) in rat liver. Different preparations of tea were evaluated for phenolic composition, antioxidant activity by DPPH assay and ability to inhibit lipid peroxidation induced by copper sulfate. The antioxidant activity was assessed in liver tissue treated with sodium azide in the presence or absence of tea by assays for lipid peroxidation (TBARS), protein oxidation (carbonyl) and the antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). The results show that different preparations of tea are important sources of polyphenols and contain theobromine, catechin and vitexin. Furthermore, the results indicate that this tea exhibits an antioxidant activity by its ability to scavenge DPPH radical. Different preparations of tea prevented damage to lipids and proteins induced by sodium azide, as well as assisting in restoring CAT and SOD activities. Thus, it can be seen that E. grandiforus tea had antioxidant activity in serum and liver being able to prevent oxidative damages generated by sodium azide.

Acute exposure to the vinyl chalcogenide 3-methyl-1-phenyl-2-(phenylseleno)oct-2-en-1-one induces oxidative stress in different brain area of rats.

The mechanisms that lead to the onset of organoselenium intoxication are still poorly understood. Therefore, in the present study, we investigated the effect of acute administration of 3-methyl-1-phenyl-2-(phenylseleno)oct-2-en-1-one on some parameters of oxidative stress and on the activity of creatine kinase (CK) in different brain areas and on the behaviour in the open field test of 90-day-old male rats. Animals (n = 10/group) were treated intraperitoneally with a single dose of the organoselenium (125, 250 or 500 µg kg(-1) ), and after 1 h of the drug administration, they were exposed to the open field test, and behaviour parameters were recorded. Immediately after they were euthanized, cerebral cortex, hippocampus and cerebellum were dissected for measurement of thiobarbituric acid reactive substances (TBARS), carbonyl, sulfhydryl, catalase (CAT), superoxide dismutase (SOD) and CK activity. Our results showed that the dose of 500 µg kg(-1) of the organoselenium increased the locomotion and rearing behaviours in the open field test. Moreover, the organochalcogen enhanced TBARS in the cerebral cortex and cerebellum and increased the oxidation of proteins (carbonyl) only in the cerebral cortex. Sulfhydryl content was reduced in all brain areas, CAT activity enhanced in the hippocampus and reduced in the cerebellum and SOD activity increased in all brain structures. The organoselenium also inhibited CK activity in the cerebral cortex. Therefore, changes in motor behaviour, redox state and energy homeostasis in rats treated acutely with organoselenium support the hypotheses that the brain is a potential target for the organochalcogen action. Ltd.

Antioxidant Activity of Grapevine Leaf Extracts against Oxidative Stress Induced by Carbon Tetrachloride in Cerebral Cortex, Hippocampus and Cerebellum of Rats.

In recent years, it has become increasingly important to study the beneficial properties of derivatives of grapes and grapevine. The objective of this study was to determine the antioxidant activity of Vitis labrusca leaf extracts, comparing conventional and organic grapevines, in different brain areas of rats. We used male Wistar rats treated with grapevine leaf extracts for a period of 14 days, and on the 15th day, we administered in half of the rats, mineral oil and the other half, carbon tetrachloride (CCl4). The animals were euthanized by decapitation and the cerebral cortex, hippocampus and cerebellum were removed to assess oxidative stress parameters and the activity of antioxidant enzymes. Lipid peroxidation levels (TBARS) were unchanged. However, CCl4 induced oxidative damage to proteins in all tissues studied, and this injury was prevented by both extracts. Superoxide dismutase (SOD) activity was increased by CCl4 in the cerebral cortex and decreased in other tissues. However, CCl4 increased catalase (CAT) activity in the cerebellum and decreased it in the cerebral cortex. The SOD/CAT ratio was restored in the cerebellum by both extracts and only in the cerebral cortex by the organic extract.