Sandra Mary Lima Vasconcelos

Espécies reativas de oxigênio e de nitrogênio, antioxidantes e marcadores de dano oxidativo em sangue humano: principais métodos analíticos para sua determinação

We review here the chemistry of reactive oxygen and nitrogen species, their biological sources and targets; particularly, biomolecules implicated in the redox balance of the human blood, and appraise the analytical methods available for their detection and quantification. Those biomolecules are represented by the enzymatic antioxidant defense machinery, whereas coadjutant reducing protection is provided by several low molecular weight molecules. Biomolecules can be injured by RONS yielding a large repertoire of oxidized products, some of which can be taken as biomarkers of oxidative damage. Their reliable determination is of utmost interest for their potentiality in diagnosis, prevention and treatment of maladies.

Oxidative stress as an underlying contributor in the development of chronic complications in diabetes mellitus.

The high prevalence of diabetes mellitus and its increasing incidence worldwide, coupled with several complications observed in its carriers, have become a public health issue of great relevance. Chronic hyperglycemia is the main feature of such a disease, being considered the responsible for the establishment of micro and macrovascular complications observed in diabetes. Several efforts have been directed in order to better comprehend the pathophysiological mechanisms involved in the course of this endocrine disease. Recently, numerous authors have suggested that excess generation of highly reactive oxygen and nitrogen species is a key component in the development of complications invoked by hyperglycemia. Overproduction and/or insufficient removal of these reactive species result in vascular dysfunction, damage to cellular proteins, membrane lipids and nucleic acids, leading different research groups to search for biomarkers which would be capable of a proper and accurate measurement of the oxidative stress (OS) in diabetic patients, especially in the presence of chronic complications. In the face of this scenario, the present review briefly addresses the role of hyperglycemia in OS, considering basic mechanisms and their effects in diabetes mellitus, describes some of the more commonly used biomarkers of oxidative/nitrosative damage and includes selected examples of studies which evaluated OS biomarkers in patients with diabetes, pointing to the relevance of such biological components in general oxidative stress status of diabetes mellitus carriers.

Characterization of blood oxidative stress in type 2 diabetes mellitus patients: increase in lipid peroxidation and SOD activity.

This study evaluated the oxidative stress through enzymatic and nonenzymatic biomarkers in diabetic patients with and without hypertension and prediabetics. The SOD and CAT (in erythrocytes) and GPx (in plasma) enzymatic activities, plasma levels of lipid peroxidation, and total thiols were measured in the blood of 55 subjects with type 2 diabetes and 38 subjects without diabetes (9 pre-diabetics and 29 controls) aged 40–86 years. The total SOD activity and the lipid peroxidation were higher in diabetics compared to nondiabetics. In stratified groups, the total SOD activity was different for the hypertensive diabetics compared to the prediabetics and normotensive controls. Lipid peroxidation was significantly higher in both groups of diabetics (hypertensive and normotensive) compared to prediabetic groups and hypertensive and normotensive controls. There was no significant difference in the CAT and GPx activities, as well as in the concentration of total thiols in the groups studied. Present data strongly suggest the involvement of oxidative stress in the pathophysiology of diabetes, revealing that the increased lipid peroxidation has a close relationship with high glucose levels, as observed by the fasting glucose and HbA1c levels. The results evidence the correlation between lipid peroxidation and DM, irrespective of the presence of hypertension.

Determinants of weight regain after bariatric surgery.

BACKGROUND Bariatric surgery leads to an average loss of 60-75% of excess body weight with maximum weight loss in the period between 18 and 24 months postoperatively. However, several studies show that weight is regained from two years of operation. AIM To identify the determinants of weight regain in post-bariatric surgery users. METHODS Prospective cross-sectional study with 64 patients who underwent bariatric surgery with postoperative time > 2 years valued at significant weight regain. The variables analyzed were age, sex, education, socioeconomic status, work activity related to food, time after surgery, BMI, percentage of excess weight loss, weight gain, attendance monitoring nutrition, lifestyle, eating habits, self-perception of appetite, daily use of nutritional supplements and quality of life. RESULTS There were 57 (89%) women and 7 (11%) men, aged 41.76 ± 7.93 years and mean postoperative period of 53.4 ± 18.4 months. The average weight and BMI were respectively 127.48 ± 24.2 kg and 49.56 ± 6.7 kg/m2 at surgery. The minimum weight and BMI were achieved 73.0 ± 18.6 kg and 28.3 ± 5.5 kg/m2, reached in 23.7 ± 12 months postoperatively. Regained significant weight occurred in 18 (28.1%) cases. The mean postoperative period of 66 ± 8.3 months and work activities related to food showed statistical significance (p=000 and p=0.003) for the regained weight. CONCLUSION Bariatric surgery promotes adequate reduction of excess body weight, with significant weight regain observed after five years; post-operative time and work activity related to eating out as determining factors for the occurrence of weight regain.

Procedimentos metodológicos empregados em questionários de frequência alimentar elaborados no Brasil: uma revisão sistemática

This review aimed to analyze and discuss the methodological procedures employed in the Food Frequency Questionnaires made in Brazil. The following databases were searched: PubMed, SciELO, Lilacs, IBECS, MedLine and the Cochrane Library. Twenty-two Food Frequency Questionnaires designed for Brazilian populations were found. Among the Food Frequency Questionnaires, 50% of them (n=11) were based on 24-hour recalls, 27.27% (n=6) were preexisting FFQ, 13.63% (n=3) were food records and 9.09% (n=2) were other types; 72.72% (n=16) had lists containing 50 to 100 items, an ideal number. Almost half the FFQ (45.45%, n=10) were quantitative, 45.45% (n=10) were semi-quantitative and 9.09% (n=2) were qualitative. Only 27.27% (n=6) were tested in a pilot study and only 36.36% (n=8) of the Food Frequency Questionnaires had a specific target audience, whether children, adolescents or adults. The Brazilian Southeast, especially the state of Sao Paulo, developed the largest number of Food Frequency Questionnaires (54.54%, n=12). The literature review helped to identify the Food Frequency Questionnaires prepared for the Brazilian population, their respective methodologies, target audience, as well as their regional distribution. Although most Food Frequency Questionnaires have been prepared following the methodological guidelines discussed here, researchers should give more attention to the criteria used for Food Frequency Questionnaires development.

Nutrition knowledge assessment studies in adults: a systematic review

The objective of this study is to perform a systematic review of published studies that assessed nutrition knowledge in adults, focusing on the methodology and content of these studies. An article search was performed on the Medline, Lilacs, and SciELO databases. The search limits were human studies; English, Portuguese, and Spanish languages; and age (over 19). Inclusion criteria were: cross-sectional studies performed on individuals over 18 years old that assessed the general nutrition knowledge of participants. The methodological quality of the articles was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) criteria. The initial search identified 3,623 articles. After reading the titles and the abstracts and applying the exclusion criteria, 25 articles were selected. The results showed that, in most studies, nutrition knowledge was associated with socioeconomic parameters and eating behaviour. Most studies belonged to class B (92%), meeting 50-80% of the STROBE criteria. The studies have revealed a greater tendency to assess the relationship of nutrition knowledge with sociodemographic and economic parameters.

Markers of redox imbalance in the blood of hypertensive patients of a community in Northeastern Brazil

BACKGROUND Recent studies describe the participation of reactive oxygen and nitrogen species in hypertension. OBJECTIVE To identify the redox imbalance in the blood of hypertensive. METHODS Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), vitamin C, transferrin, ceruloplasmin, malondialdehyde (MDA) and carbonyl group were quantified in the blood of 20 hypertensives and 21 controls. The individuals had a Body Mass Index of ≥ 18.5 and ≤ 30 kg/m(2), glycemia ≤ 100 mg/dL, serum cholesterol ≤ 200 mg/dL, and were nonsmokers, non-pregnant and non-lactating women, non-users of alopurinol and probucol, with hypertensives on antihypertensive medication. All individuals underwent a preparatory period of 4 weeks without alcohol, vitamin supplements, dexamethasone and paracetamol. RESULTS Reduced levels of CAT (p 0.013), GSH (p 0.003) and MDA (p 0.014), and high levels of GPx (p 0.001) and ceruloplasmin (p 0.015) were obtained in the hypertensive group compared with controls. A positive correlation between systolic pressure and MDA in hypertensive and diastolic pressure and CAT in controls was obtained. CONCLUSION The data obtained suggest that the hypertensives were in redox imbalance, despite the possibly attenuating effect of their antihypertensive medication.BACKGROUND: Recent studies describe the participation of reactive oxygen and nitrogen species in hypertension. OBJECTIVE: To identify the redox imbalance in the blood of hypertensive. METHODS: Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), vitamin C, transferrin, ceruloplasmin, malondialdehyde (MDA) and carbonyl group were quantified in the blood of 20 hypertensives and 21 controls. The individuals had a Body Mass Index of > 18.5 and < 30 kg/m2, glycemia < 100 mg/dL, serum cholesterol < 200 mg/dL, and were nonsmokers, non-pregnant and non-lactating women, non-users of alopurinol and probucol, with hypertensives on antihypertensive medication. All individuals underwent a preparatory period of 4 weeks without alcohol, vitamin supplements, dexamethasone and paracetamol. RESULTS: Reduced levels of CAT (p 0.013), GSH (p 0.003) and MDA (p 0.014), and high levels of GPx (p 0.001) and ceruloplasmin (p 0.015) were obtained in the hypertensive group compared with controls. A positive correlation between systolic pressure and MDA in hypertensive and diastolic pressure and CAT in controls was obtained. CONCLUSION: The data obtained suggest that the hypertensives were in redox imbalance, despite the possibly attenuating effect of their antihypertensive medication.Sandra Mary Lima Vasconcelos1,2,4, Marília Oliveira Fonseca Goulart1,2, Maria Alayde Mendonça da Silva1,5, Vanusa Manfredini6, Mara da Silveira Benfato6, Luiza Antas Rabelo1,3, Gilberto Fontes1,3 Universidade Federal de Alagoas-UFAL1, Instituto de Química e Biotecnologia-IQB2, Instituto de Ciências Biológicas e da Saúde-ICBS3, Faculdade de Nutrição-FANUT4, Faculdade de Medicina-FAMED5; Maceió, AL-Brasil. Universidade Federal do Rio Grande do Sul-UFRGS6; Porto Alegre, RS-Brasil.

Marcadores de desequilíbrio redox em sangue de pacientes hipertensos de uma comunidade no Nordeste do Brasil

BACKGROUND Recent studies describe the participation of reactive oxygen and nitrogen species in hypertension. OBJECTIVE To identify the redox imbalance in the blood of hypertensive. METHODS Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), vitamin C, transferrin, ceruloplasmin, malondialdehyde (MDA) and carbonyl group were quantified in the blood of 20 hypertensives and 21 controls. The individuals had a Body Mass Index of ≥ 18.5 and ≤ 30 kg/m(2), glycemia ≤ 100 mg/dL, serum cholesterol ≤ 200 mg/dL, and were nonsmokers, non-pregnant and non-lactating women, non-users of alopurinol and probucol, with hypertensives on antihypertensive medication. All individuals underwent a preparatory period of 4 weeks without alcohol, vitamin supplements, dexamethasone and paracetamol. RESULTS Reduced levels of CAT (p 0.013), GSH (p 0.003) and MDA (p 0.014), and high levels of GPx (p 0.001) and ceruloplasmin (p 0.015) were obtained in the hypertensive group compared with controls. A positive correlation between systolic pressure and MDA in hypertensive and diastolic pressure and CAT in controls was obtained. CONCLUSION The data obtained suggest that the hypertensives were in redox imbalance, despite the possibly attenuating effect of their antihypertensive medication.BACKGROUND: Recent studies describe the participation of reactive oxygen and nitrogen species in hypertension. OBJECTIVE: To identify the redox imbalance in the blood of hypertensive. METHODS: Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), vitamin C, transferrin, ceruloplasmin, malondialdehyde (MDA) and carbonyl group were quantified in the blood of 20 hypertensives and 21 controls. The individuals had a Body Mass Index of > 18.5 and < 30 kg/m2, glycemia < 100 mg/dL, serum cholesterol < 200 mg/dL, and were nonsmokers, non-pregnant and non-lactating women, non-users of alopurinol and probucol, with hypertensives on antihypertensive medication. All individuals underwent a preparatory period of 4 weeks without alcohol, vitamin supplements, dexamethasone and paracetamol. RESULTS: Reduced levels of CAT (p 0.013), GSH (p 0.003) and MDA (p 0.014), and high levels of GPx (p 0.001) and ceruloplasmin (p 0.015) were obtained in the hypertensive group compared with controls. A positive correlation between systolic pressure and MDA in hypertensive and diastolic pressure and CAT in controls was obtained. CONCLUSION: The data obtained suggest that the hypertensives were in redox imbalance, despite the possibly attenuating effect of their antihypertensive medication.Sandra Mary Lima Vasconcelos1,2,4, Marília Oliveira Fonseca Goulart1,2, Maria Alayde Mendonça da Silva1,5, Vanusa Manfredini6, Mara da Silveira Benfato6, Luiza Antas Rabelo1,3, Gilberto Fontes1,3 Universidade Federal de Alagoas-UFAL1, Instituto de Química e Biotecnologia-IQB2, Instituto de Ciências Biológicas e da Saúde-ICBS3, Faculdade de Nutrição-FANUT4, Faculdade de Medicina-FAMED5; Maceió, AL-Brasil. Universidade Federal do Rio Grande do Sul-UFRGS6; Porto Alegre, RS-Brasil.

ERICA: prevalence of healthy eating habits among Brazilian adolescents

ABSTRACT OBJECTIVE To describe the prevalence of eating habits considered healthy in adolescents according to sex, age, education level of the mother, school type, session of study, and geographic region. METHODS The assessed data come from the Study of Cardiovascular Risks in Adolescents (ERICA), a cross-sectional, national and school-based study. Adolescents of 1,247 schools of 124 Brazilian municipalities were evaluated using a self-administered questionnaire with a section on aspects related to eating behaviors. The following eating behaviors were considered healthy: consuming breakfast, drinking water, and having meals accompanied by parents or legal guardians. All prevalence estimates were presented proportionally, with their respective 95% confidence intervals. The Chi-square test was used to evaluate the differences in healthy eating habits prevalences according to other variables. The module survey of the Stata program version 13.0 was used to analyze complex data. RESULTS We evaluated 74,589 adolescents (72.9% of the eligible students). Of these, 55.2% were female, average age being 14.6 years (SD = 1.6). Among Brazilian adolescents, approximately half of them showed healthy eating habits when consuming breakfast, drinking five or more glasses of water a day, and having meals with parents or legal guardians. All analyzed healthy eating habits showed statistically significant differences by sex, age, type of school, session of study, or geographic region . CONCLUSIONS We suggest that specific actions of intersectoral approach are implemented for the dissemination of the benefits of healthy eating habits. Older female adolescents (15 to 17 years old) who studied in public schools, resided in the Southeast region, and whose mothers had lower education levels, should be the focus of these actions since they present lower frequencies concerning the evaluated healthy habits.

ERICA: use of screens and consumption of meals and snacks by Brazilian adolescents

ABSTRACT OBJECTIVE To describe the length of exposure to screens and the prevalence of consumption of meals and snacks by Brazilian adolescents in front of screens. METHODS We evaluated 74,589 12 to 17-year old adolescents from 1,247 schools in 124 Brazilian municipalities. A self-administered questionnaire was used. Its segment regarding nutrition contained questions about using TV, computers, and video game systems, having meals while watching TV, and consuming snacks in front of screens. Consumption of meals and snacks in front of screens was analyzed according to the following variables: geographical region, gender, age range, type of school (public or private), and school shift. The prevalences and their respective 95% confidence intervals were estimated under a complex sampling design. RESULTS A great deal of the adolescents (73.5%, 95%CI 72.3-74.7) reported spending two or more hours a day in front of screens. That habit was more frequent among male adolescents, private school students, morning shift students, and students from Brazil’s South region. More than half of the adolescents (56.6%, 95%CI 55.4-57.8) reported almost always or always having meals in front of TV, and 39.6% (95%CI 38.8-40.5) of them said they consumed snacks in front of screens exactly as often. Both situations were the most prevalent ones among the girls, who attended public schools and were from Brazil’s Midwest region. CONCLUSIONS Length of exposure to screens and consumption of meals and snacks almost always or always in front of screens are high among Brazilian adolescents. It is necessary to develop strategies aiming to reduce the length of screen use, considering the media reality that children and adolescents have been experiencing from earlier and earlier ages. That context must therefore be analyzed in an indissociable way.