Rejane Giacomelli Tavares

Chronic administration of methionine and/or methionine sulfoxide alters oxidative stress parameters and ALA-D activity in liver and kidney of young rats

High levels of methionine (Met) and methionine sulfoxide (MetO) are found in several genetic abnormalities. Oxidative stress is involved in the pathophysiology of many inborn errors of metabolism. However, little is known about the role of oxidative damage in hepatic and renal changes in hypermethioninemia. We investigated the effect of chronic treatment with Met and/or MetO on oxidative stress parameters in liver and kidney, as lipid peroxidation (TBARS), total sulfhydryl content (SH), reactive oxygen species (ROS) and enzymes activities superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and delta aminolevulinic dehydratase (ALA-D). Serum biochemical parameters were evaluated. Wistar rats were treated daily with two subcutaneous injections of saline (control), Met (0.2–0.4xa0g/kg), MetO (0.05–0.1xa0g/kg) and the association between these (Met plus MetO) from the 6th to the 28thxa0day of life. Our data demonstrated an increase of glucose and urea levels in all experimental groups. Cholesterol (MetO and Met plus MetO) were decreased and triglycerides (MetO) were increased. SOD (MetO and Met plus MetO) and CAT (Met, MetO and Met plus MetO) activities were decreased, while GPx was enhanced by MetO and Met plus MetO treatment in liver. In kidney, we observed a reduction of SH levels, SOD and CAT activities and an increase of TBARS levels in all experimental groups. ROS levels in kidney were increased in MetO and Met plus MetO groups. ALA-D activity was enhanced in liver (MetO and Met plus MetO) and kidney (Met plus MetO). These findings help to understand the pathophysiology of hepatic and renal alterations present in hypermethioninemia.

Vaccinium virgatum fruit extract as an important adjuvant in biochemical and behavioral alterations observed in animal model of metabolic syndrome

The aim of this study was to investigate the effect of blueberry (Vaccinium virgatum) fruit extract on metabolic, behavioral and oxidative stress parameters in the hippocampus and cerebral cortex of mice submitted to an experimental model of metabolic syndrome induced by a highly palatable diet (HPD). Mice C57BL/6 were divided into 4 experimental groups: (1) received standard chow and saline orally, (2) received standard chow and blueberry hydroalcoholic extract, (3) received HPD and saline orally, (4) received HPD and blueberry hydroalcoholic extract. The animals were treated for 150days. Our results showed that the animals fed with HPD presented insulin resistance, increased body weight, visceral fat, glucose, triglycerides, and total cholesterol when compared to the control group. The blueberry extract prevented the increase of these metabolic parameters. Also, the extract was able to reduce the levels of thiobarbituric acid reactive substances in the cerebral cortex and hippocampus of animals submitted to HPD. In contrast, no differences were observed in the total thiol content, activity of the antioxidant enzymes catalase and superoxide dismutase. In addition, the HPD fed animals showed a significant increase in immobility time in the forced swimming test and blueberry prevented this alteration, although no changes were observed in the ambulatory behavior, as well as in the anxiolytic profile of these animals. Overall, our findings suggest that chronic consumption of blueberry extract exhibits hypoglycemic, hypolipidemic, antidepressant-like and antiperoxidative effects in an animal model of metabolic syndrome.

Antioxidant, antihyperglycemic, and antidyslipidemic effects of Brazilian-native fruit extracts in an animal model of insulin resistance

ABSTRACT Objective: Insulin resistance (IR) plays an important role in the development of many diseases, such as diabetes mellitus. Therefore, the aim of the present study was to evaluate the effects of the extracts from fruits native to Brazil on metabolic parameters and hepatic oxidative markers in an animal model of insulin resistance induced by dexamethasone (DEX). Methods: Wistar rats received water or extracts of Eugenia uniflora or Psidium cattleianum, once a day for 21 days. For the last 5 days, the rats received an intraperitoneal injection of saline or DEX. Results: DEX caused a reduction in body weight gain and relative pancreatic weight, as well as glucose intolerance, and an increase in serum glucose and triacylglycerol levels. The extracts were found to prevent hyperglycemia and hypertriglyceridemia. DEX caused an increase in the levels of thiobarbituric acid-reactive substances and reactive oxygen species production in the liver of rats, and both extracts prevented these changes. In addition, hepatic glutathione peroxidase activity was reduced by DEX. However, total thiol content and activities of catalase, superoxide dismutase, and delta-aminolevulinate dehydratase were not altered in any of the tested groups. Conclusion: Fruit extracts of E. uniflora and P. cattleianum exhibited considerable antihyperglycemic, antidyslipidemic, and antioxidant effects, and may be useful in the therapeutic management of alterations due to IR.

Methionine and methionine sulfoxide treatment induces M1/classical macrophage polarization and modulates oxidative stress and purinergic signaling parameters

Methionine is an essential amino acid involved in critical metabolic process, and regulation of methionine flux through metabolism is important to supply this amino acid for cell needs. Elevation in plasma methionine commonly occurs due to mutations in methionine-metabolizing enzymes, such as methionine adenosyltransferase. Hypermethioninemic patients exhibit clinical manifestations, including neuronal and liver disorders involving inflammation and tissue injury, which pathophysiology is not completely established. Here, we hypothesize that alterations in macrophage inflammatory response may contribute to deleterious effects of hypermethioninemia. To this end, macrophage primary cultures were exposed to methionine (1xa0mM) and/or its metabolite methionine sulfoxide (0.5xa0mM), and M1/proinflammatory or M2/anti-inflammatory macrophage polarization was evaluated. In addition, inflammation-related pathways including oxidative stress parameters, as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities; reactive oxygen species (ROS) production, and purinergic signaling, as ATP/ADP/AMPase activities, were investigated. Methionine and/or methionine sulfoxide induced M1/classical macrophage activation, which is related to proinflammatory responses characterized by increased iNOS activity and TNF-α release. Further experiments showed that treatments promoted alterations on redox state of macrophages by differentially modulated SOD and CAT activities and ROS levels. Finally, methionine and/or methionine sulfoxide treatment also altered the extracellular nucleotide metabolism, promoting an increase of ATPase/ADPase activities in macrophages. In conclusion, these findings contribute to better understand the participation of proinflammatory responses in cell injury observed in hypermethioninemic patients.

Preventive effects of blueberry extract on behavioral and biochemical dysfunctions in rats submitted to a model of manic behavior induced by ketamine

The aim of the present study was to evaluate the protective effects of blueberry extract on oxidative stress and inflammatory parameters in a model of mania induced by ketamine administration in rats. Male rats were pretreated with blueberry extract (200mg/kg, once a day for 14days), lithium chloride (45mg/kg, mood stabilizer used as a positive control, twice a day for 14days), or vehicle. Between the 8th and 14th days, rats also received an injection of ketamine (25mg/kg) or vehicle. In the 15th day, thirty minutes after ketamine administration the hyperlocomotion of the animals was assessed in the open - field apparatus. Immediately after the behavioral analysis brain and blood were collected for biochemical determinations. ketamine treatment induced hyperlocomotion and oxidative damage in cerebral cortex, hippocampus and striatum such as an increase in lipid peroxidation and a decrease in the antioxidant enzymes activities (superoxide dismutase, catalase e glutatione peroxidase). Ketamine administration also increased the IL-6 levels in serum in rats. Pretreatment of rats with blueberry extract or lithium prevented the hyperlocomotion, pro - oxidant effects and inflammation induced by ketamine. Our findings suggest that blueberry consumption has a neuroprotective potential against behavioral and biochemical dysfunctions induced in a preclinical model that mimic some aspects of the manic behavior.

Eugenia uniflora fruit (red type) standardized extract: a potential pharmacological tool to diet-induced metabolic syndrome damage management

The aim of this study was to investigate the effect of Eugenia uniflora fruit (red type) extract on metabolic status, as well as on neurochemical and behavioral parameters in an animal model of metabolic syndrome induced by a highly palatable diet (HPD). Rats were treated for 150days and divided into 4 experimental groups: standard chow (SC) and water orally, SC and E. uniflora extract (200mg/kg daily, p.o), HPD and water orally, HPD and extract. Our data showed that HPD caused glucose intolerance, increased visceral fat, weight gain, as well as serum glucose, triacylglycerol, total cholesterol and LDL cholesterol; however, E. uniflora prevented these alterations. The extract decreased lipid peroxidation and prevented the reduction of superoxide dismutase and catalase activities in the prefrontal cortex, hippocampus and striatum of animals submitted to HPD. We observed a HPD-induced reduction of thiol content in these cerebral structures. The extract prevented increased acetylcholinesterase activity in the prefrontal cortex caused by HPD and the increase in immobility time observed in the forced swim test. Regarding chemical composition, LC/MS analysis showed the presence of nine anthocyanins as the major compounds. In conclusion, E. uniflora extract showed benefits against metabolic alterations caused by HPD, as well as exhibited antioxidant and antidepressant-like effects.

Performance analysis of software for identification of intestinal parasites

Introduction:Intestinal parasites are among the most frequent diagnoses worldwide. An accurate clinical diagnosis of human parasitic infections depends on laboratory confirmation for specific differentiation of the infectious agent.Objectives:To create technological solutions to help parasitological diagnosis, through construction and use of specific software.Material and method:From the images obtained from the sediment, the software compares the morphometry, area, perimeter and circularity, and uses the information on specific morphological and staining characteristics of parasites and allows the potential identification of parasites.RESULTS:Our results demonstrate satisfactory performance, from a total of 204 images analyzed, 81.86% had the parasite correctly identified by the computer system, and 18.13% could not be identified, due to the large amount of fecal debris in the sample evaluated.Discussion:Currently the techniques used in Parasitology area are predominantly manual, probably being affected by variables, such as attention and experience of the professional. Therefore, the use of computerization in this sector can improve the performance of parasitological analysis.Conclusions:This work contributes to the computerization of healthcare area, and benefits both health professionals and their patients, in addition to provide a more efficient, accurate and secure diagnosis.

Harmonization study of results between biochemical analyzers Labmax 240® and Labmax 240 Premium®

Introduction: The harmonization of equipment is recommended in clinical laboratory practice aiming for the homogeneity of results when similar or equivalent analyzers are used to perform routine testing. Objectives: To conduct a study of equivalence between the biochemical analyzers Labmax 240 (E1) and Labmax 240 Premium (E2) through the matching results and the statistical value analysis of dosages. Materials and methods: We evaluated tests with glucose, total cholesterol, triglycerides, uric acid, aspartate transaminase (AST), alanine transaminase (ALT) and lactate dehydrogenase (LDH), all with 40 repeated measurements, performed in both equipments. The Clinical and Laboratory Standards Institute (CLSI) EP09-3A protocol was used to conduct the comparison test between E1 and E2 equipment, with subsequent evaluation of the results for statistical analysis determining the Pearson correlation coefficient (r) and indexes comparison error with EP Evaluator software. Results: Regarding the values of the Pearson correlation coefficient, all tests showed a strong correlation between equipment with r > 0.989, except for the dosage of LDH (r = 0.982). This dosage failed not because the value of r, but due to the values obtained in the error index being larger than the total errors index allowed. Discussion: Compared to clinical criteria, the results of the analyzers are approximately equal, but this control process must be done continuously in order to prevent and track random errors within the laboratory routine. Conclusion: The process of harmonization of multiple devices that perform the same laboratory parameters is essential for ensuring quality and reliability of laboratory results and should be standardized and included in routine clinical analysis laboratories.

Lack of association between helicobacter pylori's virulence and increased serum C-reactive protein levels in functional dyspeptic patients

BACKGROUNDnRecently, a great variety of studies aimed to investigate and even suggest Helicobacter pylori as an important key factor in gastrointestinal and non-gastrointestinal events development. The well-established relationship between bacterial virulence and increased risk for peptic ulcer or gastric carcinoma is not so clear when comparing inflammation markers alterations, such C-reactive protein, with the pathogen.nnnOBJECTIVEnThe objective of this study was to evaluate the presence of H. pylori, bacterial virulence and C-reactive protein serum levels in individuals diagnosed with functional dyspepsia.nnnMETHODSnWere prospectively included in this study 489 dyspeptic individuals. They fulfill Rome III clinical criteria for the diagnosis of functional dyspepsia with no organic disease at endoscopy. The bacterial infection was established by histology and urease rapid test. The levels of serum C-reactive protein were obtained by immunonefelometry and CagA status of H. pylori positive individuals was determined through an imunoenzimatic assay.nnnRESULTSnPrevalence rate of H. pylori was 66.3% and virulence factor CagA was detected in nearly 43% of positive samples. In addition, it has been noticed an association between Ilex paraguariensis (yerba maté) consumption and pathogens prevalence. An important effect of bacterial infection on inflammation was only observed in gastric epithelium.nnnCONCLUSIONnNo systemic response to the pathogen, measured through C-reactive protein levels, was observed, regardless of CagA status. Otherwise, the intake of yerba maté should be considered as a cultural factor possibly related to H. pyloris transmission.