Metabolite of tryptophan promoting changes in EEG signal and the oxidative status of the brain.

Tryptophan is an essential amino acid precursor of neurotransmitter serotonin and triptamine. During its metabolism, indole-3-acetic acid (IAA) is generated; this substance presents both antioxidant and prooxidant effects in different biological systems in addition to hipoglicemic effects. To date, electroencephalography (EEG) has been used to evaluate the temporal effect of several substances in neurotransmission. The goal of this study was to characterize the effect of IAA in the brain by analysing the EEG signal and evaluate the oxidative status by means of biochemical parameters. The EEG was acquired by using a noninvasive method, and the brain electric signal was analysed by advanced digital signal processing techniques to determinate the energy signal filtered in different band frequencies. Furthermore, the oxidative status of the brain was investigated by measuring the activity of antioxidant enzymes and lipid peroxidation as well as blood glucose rates of the animals treated with different doses of IAA. Our results showed the relationship of IAA administration with changes in EEG signals. The oxidative status of the brain was modified by IAA after 14 days of treatment.

Effects of copper and selenium supplementation on performance and lipid metabolism in confined brangus bulls.

Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on performance, feed efficiency, composition of fatty acids in Longissimus dorsi (LD) muscle, and cholesterol concentration in serum and in LD muscle and enzymes activities, reduced glutathione (GSH) and oxidized glutathione (GSSG). The treatments were: i) Control, without copper (Cu) and selenium (Se) supplementation; ii) Se, 2 mg Se/kg of dry matter such as sodium selenite; iii) Cu, 40 mg Cu/kg of dry matter such as copper sulfate; iv) Se/Cu, 2 mg Se/kg of dry matter such as sodium selenite and 40 mg Cu/kg of dry matter such as copper sulfate. LD muscle fatty acid composition was not influenced by the treatments (p>0.05). The serum concentration of cholesterol was not influenced by the treatments (p>0.05), however, the concentration of cholesterol in LD was lower in cattle supplemented with copper and selenium (p<0.05). Oxidized glutathione and reduced glutathione increased (p<0.05) with Cu, Se and Se/Cu supplementation. The supplementation of copper (40 mg/kg DM) and selenium (2 mg/kg DM) altered the metabolism of lipids in confined Brangus cattle, through a decrease in cholesterol deposition in the LD, possibly by changing the ratio between reduced glutathione/oxidized glutathione. Copper and selenium supplementation improved animal performance and feed efficiency (p<0.05) when compared to the control group, providing advantages in the production system, while also benefiting consumers by reducing cholesterol concentration in the meat.

Copper and zinc hydroxychloride cosupplementation improve growth performance and carcass and reduce diarrhea frequency in grower-finisher pigs.

This study investigated copper (Cu) and zinc (Zn) hydroxychloride cosupplementation on the growth performance, diarrhea frequency, carcass, meat quality, and antioxidant activity in grower-finisher pigs. A total of 256 pigs were used from 70 to 154 days (d) of age, distributed in four treatments, with eight pigs in each pen and eight replications per treatment. Diets were provided to grower pigs from 70 to 112 days old and in the finisher, 112 to 154 days old. Copper was considered the low level at 100 mg Cu/kg and 90 mg Cu/kg, respectively, and 150 mg Cu/kg in both periods as high in the grower and finisher periods. In the grower and finisher period, zinc was cosupplemented in the diet at 80 mg Zn/kg and 70 mg Zn/kg, respectively. In the diets, T1 and T2 groups are the traditional inorganic sources for minerals (copper sulfate, CuSO4; zinc oxide, ZnO) and T3 and T4 hydroxychloride sources (copper hydroxychloride, CHC, and zinc hydroxychloride, ZHC). The flavomycin was associated with treatments with low Cu content in the inclusion of 50 g/ton. The experimental design was in randomized blocks, the data were submitted to analysis of PROC MIXED in SAS, the PDIFF test analyzed the treatment effect. At the finisher period, pigs fed both minerals from hydroxychloride source had a higher BW 154 d, average daily gain (ADG) 70 to 154 d, the hot and cold carcass weight and frequency of normal feces than those fed 150 mg Cu/kg and Zn from a traditional inorganic source (P < 0.05). The animals fed low Cu levels of the sulfate source had a higher ADG 70 to 154 d than those fed high Cu levels of the same source (P < 0.05). Pigs fed 150 mg Cu/kg cosupplemented with Zn from a hydroxychloride source had the highest carcass length (P < 0.05). There was no difference among the treatments for meat quality (P > 0.05). Pigs fed 150 mg Cu/kg and Zn from a traditional inorganic source had a higher superoxide dismutase (SOD) activity than the other treatments (P < 0.05). Animals fed low Cu levels from hydroxychloride had a higher malondialdehyde (MDA) formation than those fed sulfate source, regardless of the Cu levels and those fed high Cu levels of hydroxychloride (P < 0.05). In conclusion, 150 mg Cu/kg as copper sulfate cosupplemented to zinc oxide in the diet of growing and finishing pigs impairs the growth performance, carcass and increases diarrhea frequency, and copper and zinc hydroxychloride cosupplementation improves these characteristics.

Evaluation of liquid and powdered forms of polyclonal antibody preparation against Streptococcus bovis and Fusobacterium necrophorum in cattle adapted or not adapted to highly fermentable carbohydrate diets.

OBJECTIVE: Feed additives that modify rumen fermentation can be used to prevent metabolic disturbances such as acidosis and optimize beef cattle production. The study evaluated the effects of liquid and powdered forms of polyclonal antibody preparation (PAP) against Streptococcus bovis and Fusobacterium necrophorum on rumen fermentation parameters in ruminally cannulated non-lactating dairy cows that were adapted or unadapted to a high concentrate diet. METHODS: A double 3×3 Latin square design was used with three PAP treatments (control, powdered, and liquid PAP) and two adaptation protocols (adapted, unadapted; applied to the square). Adapted animals were transitioned for 2 weeks from an all-forage to an 80% concentrate diet, while unadapted animals were switched abruptly. RESULTS: Interactions between sampling time and adaptation were observed; 12 h after feeding, the adapted group had lower ruminal pH and greater total short chain fatty acid concentrations than the unadapted group, while the opposite was observed after 24 h. Acetate:propionate ratio, molar proportion of butyrate and ammonia nitrogen concentration were generally greater in adapted than unadapted cattle up to 36 h after feeding. Adaptation promoted 3.5 times the number of Entodinium protozoa but copy numbers of Streptococcus bovis and Fibrobacter succinogens genes in rumen fluid were not affected. However, neither liquid nor powdered forms of PAP altered rumen acidosis variables in adapted or unadapted animals. CONCLUSION: Adaptation of cattle to highly fermentable carbohydrate diets promoted a more stable ruminal environment, but PAP was not effective in this study in which no animal experienced acute or sub-acute rumen acidosis.

Microbicidal action of indole-3-acetic acid combined with horseradish peroxidase on Prototheca zopfii from bovine mastitis.

We investigated the toxic effect of indole-3-acetic acid (IAA) combined with horseradish peroxidase (HRP) on Prototheca zopfii from bovine mastitis. P. zopfii isolates were identified and characterized by morpho-physiological parameters; presences of P. zopfii genotype 2 were also investigated. Subsequently, P. zopfii was incubated in the absence (control) or presence of IAA/HRP and examined for: (i) cell viability; (ii) colonies number formation; (iii) antioxidant enzyme activity; and (iv) DNA integrity. Significance of differences was calculated using ANOVA and Tukey's test (P < or = 0.05). As evidenced by Trypan blue exclusion and colony formation in Sabouraud dextrose agar, IAA/HRP addition to the culture reduced respective P. zopfii viability and P. zopfii colony formation in a concentration- and time-dependent manner. IAA/HRP specifically reduced cell viability in 10, 15, 20, 25, and 32% after 4, 6, 8, 10, and 12 h of incubation, respectively, compared with the control at the same time. The number of colony formation was inhibited (45, 82, and 88%) by IAA/HRP after 4, 6, and 9 h of incubation, respectively, compared with the control at the same time. In addition, P. zopfii antioxidant activity increased measurably in the presence of IAA/HRP (6 h); superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase increased by 90, 120, 150% and 3.4 times, compared with the controls. IAA/HRP did not appear to effect P. zopfii DNA integrity when examined by electrophoresis. In conclusion, IAA/HRP appears to function as a microbicidal mechanism on P. zopfii genotype 2 from bovine mastitis.

Antioxidant and anti-inflammatory properties of orally disintegrating films based on starch and hydroxypropyl methylcellulose incorporated with Cordia verbenacea (erva baleeira) extract.

Cordia verbenacea (erva baleeira) is a plant used in indigenous folk medicine. Due to its pharmacological properties (antioxidant and anti-inflammatory), it can be used in the development of herbal medicines by different forms of administration such as orally disintegrating films (ODFs), which would facilitate the systemic release of its active ingredients. Considering the properties of the C. verbenacea and the advantages of ODFs, the objective of this work was the potential development of ODFs with antioxidant and anti-inflammatory properties. The polymeric matrices were produced based on starch and hydroxypropyl methylcellulose and additives with different C. verbenacea extract concentrations in order to obtain concentrations of 0.25, 0.50 and 0.75 mg flavonoids/ODF. The films were characterized by microscopy, infrared spectroscopy, mechanical properties, mucoadhesiveness, in vitro disintegration, in vitro release of flavonoids, antioxidant, and anti-inflammatory activities of the films. The ODFs showed good antioxidant activity and high anti-inflammatory capacity with inhibition of COX-2 enzyme. The stability study demonstrated the conservation of flavonoids and also the maintenance of the anti-inflammatory capacity of ODFs. This study demonstrated that orally disintegrating films have high potential for the delivery of natural bioactive compounds and the maintenance of their pharmacological properties.

In vitro antioxidant activity of olive leaf extract (Olea europaea L.) and its protective effect on oxidative damage in human erythrocytes.

AIMS: This study aimed to evaluate in vitro antioxidant capacity of olive leaf extract (OLE), Olea europaea L., and its protective effect on peroxyl radical-induced oxidative damage in human erythrocytes. MAIN METHODS: The OLE was evaluated by the following assays: i) total phenolic and flavonoid content; ii) oleuropein content; iii) Ferric reducing antioxidant power (FRAP); iv) antioxidant activity against ABTS•+, DPPH• and reactive oxygen and nitrogen species: superoxide anion ( O2·- ), hypochlorous acid (HOCl) and nitric oxide (NO•) and v) protective effect on peroxyl radical-induced oxidative damages in human erythrocytes as hemolysis, thiobarbituric acid reactive substances (TBARS) formation and oxyhemoglobin oxidation. KEY FINDINGS: Total phenolic and flavonoid contents were 131.7 ± 9.4 mg gallic acid equivalents/g dry weight (dw) and 19.4 ± 1.3 mg quercetin equivalents/g dw, respectively. Oleuropein content was 25.5 ± 5.2 mg/g dw. FRAP analysis was 281.8 ± 22.8 mg trolox equivalent/g dw and OLE inhibited ABTS•+ (50% effective concentration (EC50) = 16.1 ± 1.2 µg/mL) and DPPH• (EC50 = 13.8 ± 0.8 µg/mL). The extract demonstrated effective ability to scavenge O2·-  (EC50 = 52.6 ± 2.1 µg/mL), NO• (EC50 = 48.4 ± 6.8 µg/mL) and HOCl (EC50 = 714.1 ± 31.4 µg/mL). The extract inhibited peroxyl radical-induced hemolysis (EC50 = 11.5 ± 1.5 µg/mL), TBARS formation (EC50 = 38.0 ± 11.7 µg/mL) and hemoglobin oxidation (EC50 = 186.3 ± 29.7 µg/mL) in erythrocytes. SIGNIFICANCE: OLE is an important source of natural antioxidants; it has effective antioxidant activity against different reactive species and protects human erythrocytes against oxidative damage.

Evaluation of the antimicrobial activity and cytotoxic effect of hydroxyapatite containing Brazilian propolis.

The aim of this work was to produce hydroxyapatite powder (HA) containing the dry extract of green and red propolis, and to evaluate the possible bactericidal activity of these materials over a short period of time through a fast release system. The ethanolic extracts of green and red propolis (EEP) were incorporated into the material by spray drying. After release tests, powders containing dry EEP were characterized regarding the content of total phenolics and flavonoids. Material characterization was undertaken by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The antimicrobial activity was evaluated by plate colony counting, minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) against Staphylococcus aureus (S. aureus). The cytotoxicity of the materials was determined by the neutral red incorporation method. The materials showed apparently spherical morphology, indicating a decrease in the degree of agglomeration with the addition of propolis. Characteristic HA and propolis functional groups were observed in the FTIR. The materials showed a higher release of phenolics and lower amounts of flavonoids when compared to the EEP, with the higher amounts of flavonoids observed for HA with red propolis. A bactericidal effect was observed for all materials within the interval of 0.5 and 1 h, showing lower inhibitory activity (MIC) and higher bactericidal activity (MBC) when compared to the EEP, with the best results attributed to HA with red propolis. The IC50 values (which is the concentration needed to inhibit cell growth by 50%) obtained from the cytotoxicity assay for HA with the green and red propolis lay between MIC and MCB. Considering these results, it is suggested that HA and propolis may be used as a possible antimicrobial agent, inhibiting the growth of S. aureus, although further in vivo biocompatibility should be investigated before using this material as a medical device with bactericidal potential.

Effect of Cysticercus cellulosae fractions on the respiratory burst of pig neutrophils.

Neutrophils, eosinophils and macrophages are cells that interact with invading parasites and naive hosts have been shown to have anti-parasitic activity. The initial reaction of these leukocytes is the generation of reactive oxygen species (ROS) to play in parasite expulsion. The present work was carried out to study the effect of total extract, scolex and membrane fractions from Cysticercus cellulosae on respiratory burst by pig neutrophils. Hydrogen peroxide (H2O2) production by neutrophils incubated with metacestode fractions from C. cellulosae showed an increase of: 190% (total extract), 120% (scolex) and 44% (membrane). High antioxidant catalatic activity (33%, 28%, 28% by total extract, scolex and membrane, respectively) was observed in neutrophils incubated with metacestode fractions, which could be an attempt at self-protection. Scolex and membrane fractions increased the phagocytic capacity of neutrophils (44% and 28%, respectively). On the other hand, total cysticerci did not alter the phagocytosis, possibly due to modifications in membrane function, caused by high ROS production from neutrophils in the presence of total cysticerci. Total fraction from C. cellulosae is toxic for neutrophils as shown by the decrease in phagocytic capacity, probably caused by high levels of ROS formation. The difference in toxicity of total extract, scolex and membrane fractions on neutrophils can be explained by the presence of an antigenic effect of the vesicular fluid in the total extract of C. cellulosae.

The mechanism of indole acetic acid cytotoxicity.

The cytotoxic effect of IAA (1 mM) was examined in rat neutrophils and lymphocytes by: loss of membrane integrity (necrosis), DNA fragmentation, chromatin condensation and mitochondrial transmembrane potential (apoptosis). The following conditions were studied: (1) rat neutrophils (high peroxidase activity; (2) rat lymphocytes in the absence and presence of horseradish peroxidase; and (3) rat lymphocytes co-cultivated with rat neutrophils. Incubation of neutrophils with IAA induced loss of membrane integrity, chromatin condensation and DNA fragmentation. The same was observed in lymphocytes incubated with HRP and IAA or co-cultivated with neutrophils in the presence of IAA. Neutrophils and lymphocytes incubated with IAA presented a more pronounced depolarization of mitochondrial transmembrane potential after 12 h treatment. Incubation for 24 h in the presence of IAA (1 mM) showed increase in the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase. The addition of exogenous antioxidant enzymes (SOD and CAT) prevented the loss of cell membrane integrity induced by IAA. Therefore, the process of cell death induced by IAA involves ROS production.

Effect of supplementation of two sources and two levels of copper on lipid metabolism in Nellore beef cattle.

UNLABELLED: This study was conducted with 35 Nellore beef cattle to determine the effect of supplementation of two levels and two copper sources (organic and inorganic) on metabolism of lipids and cholesterol of meat. The five treatments used were: CONTROL: without copper supplementation, I10 or I40: 10 or 40 mg/kg DM (as Cu sulfate), O10 or O40: 10 or 40 mg/kg DM (as Cu proteinate). In general, the copper supplementation changed the fatty acid profile of meat (p<0.05), with a higher proportion of unsaturated fatty acids and reduction of saturated fatty acids. There was no effect of supplementation on blood cholesterol and triglycerides, however; in general, there was a reduction in cholesterol concentration in the L. dorsi (p<0.05) compared to the control treatment through the reduction (p<0.05) in the concentrations of GSH and GSH/GSSG ratio. The Cu supplementation did have an influence on metabolism of lipids. The production of healthier meat is beneficial to public health by reducing the risk of cardiovascular disease.

Influence of indole acetic acid on antioxidant levels and enzyme activities of glucose metabolism in rat liver.

Indole acetic acid (IAA) is an auxin and can be synthesized in animals. This compound is metabolized in vitro by peroxidase, producing reactive oxygen species. The toxic effect of indole acetic acid in leukocytes is associated with peroxidase activities and these processes have been implicated in activation of glucose and glutamine metabolism. However, studies in vitro have shown that IAA, in absence of peroxidase, is an antioxidant almost as high in potency as those of other indolic compounds. The purpose of this study was to investigate the possible involvement of a toxic effect of indole acetic acid in the liver, as evidenced by oxidative stress and enzyme activities of the glucose pathway. The animals received IAA by subcutaneous or gavage administration in a phosphate buffered saline (the control group received only the phosphate buffered saline). The other groups received IAA at concentrations of 1 mg, 18 mg and 40 mg per kg of body mass per day. Treatments with 18 mg and 40 mg IAA decreased the activity of catalase by both subcutaneous (30% and 26%) or gavage administration (19% and 28%), respectively. A similar effect was observed on the activity of glutathione peroxidase of animals exposed to 18 mg and 40 mg IAA: A decrease of 34% and 29%, respectively, for subcutaneous administration and a decrease of 29% and 25%, respectively, for gavage administration. However, in neither source of administration did the acid alter superoxide dismutase, glutathione reductase and myeloperoxidase activities. Another alteration was observed in respect of reduced glutathione content in this organ. The lipid peroxidation level showed a significant decrease with subcutaneous (30%, 29% and 24%) and gavage administration (25%, 26% and 24%) using 1 mg, 18 mg and 40 mg of IAA, respectively compared with the control. The reduced glutathione content and catalase activity in the plasma were not altered by either of the two methods of administration. In addition to these findings, after subcutaneous or gavage administration of IAA, the activities of hepatic enzymes of glucose metabolism were not affected (glucokinase, lactate dehydrogenase, glucose-6-phosphate dehydrogenase and citrate synthase). Evidence is presented herein that IAA did not have a pro-oxidant effect in the liver as deduced from a reduction of catalase and glutathione peroxidase activities, a decrease of lipid peroxidation content and no alteration of the pool of reduced glutathione. The effects of IAA were independent of the way of administration.

Glucose and glutamine utilization by rat lymphocytes, monocytes and neutrophils in culture: a comparative study.

Glucose and glutamine utilization and production of glutamate and lactate were determined for up to 48 h in lymphocytes, monocytes and neutrophils cultured in medium rich in metabolites and vitamins. Glucose was utilized by the three cell types in culture in the following order: neutrophils > monocytes > lymphocytes, whereas lactate was produced in the order: monocytes > neutrophils > lymphocytes. The consumption of glucose followed the activity of glucose-6-phosphate dehydrogenase but it was not related to hexokinase activity. Glutamine was consumed by the three leukocyte types in culture as follows: neutrophils > lymphocytes > or = monocytes. The consumption of glutamine was not fully related to the activity of phosphate-dependent glutaminase. The production of glutamate was not remarkably different among the three cell types. For comparison, glutamine and glucose utilization and glutamate and lactate production were also evaluated using 1-h incubated leukocytes. Under this condition, only glucose or glutamine was added to the medium. Glucose was utilized as follows: neutrophils > monocytes > lymphocytes, whereas lactate was produced in the following order: monocytes > or = neutrophils > lymphocytes. Glutamine was consumed as follows: neutrophils > lymphocytes > monocytes, whereas glutamate was produced as follows: neutrophils > or = monocytes = lymphocytes. The ratio of the amount of glucose/glutamine consumed by 1-h incubated cells was 0.5 for neutrophils, 1.5 for monocytes, and 0.3 for lymphocytes. However, the three cell types cultured for 48 h utilized glucose to a much higher degree than glutamine. The ratio of the amount of glucose/glutamine utilized by the cultured cells was 8.9 for neutrophils, 16.4 for monocytes, and 6.7 for lymphocytes. These observations support the proposition that glutamine is required in much higher amounts than glucose to accomplish the total metabolic requirement of leukocytes. Under conditions closer to physiological when the availability of a variety of metabolites and vitamins is not restricted, glucose is the preferred substrate for lymphocytes, monocytes and neutrophils.