Flávia Troncon Rosa

Effects of creatine supplementation on oxidative stress and inflammatory markers after repeated-sprint exercise in humans.

OBJECTIVE The goal of this study was to evaluate the effects of creatine (Cr) supplementation on oxidative stress and inflammation markers after acute repeated-sprint exercise in humans. METHODS Twenty-five players under age 20 y were randomly assigned to two groups: Cr supplemented and placebo. Double-blind controlled supplementation was performed using Cr (0.3 g/kg) or placebo tablets for 7 d. Before and after 7 d of supplementation, the athletes performed two consecutive Running-based Anaerobic Sprint Tests (RAST). RAST consisted of six 35-m sprint runs at maximum speed with 10 sec rest between them. Blood samples were collected just prior to start of test (pre), just after the completion (0 h), and 1 h after completion. RESULTS Average, maximum, and minimum power values were greater in the Cr-supplemented group compared with placebo (P < 0.05). There were significant increases (P < 0.05) in plasma tumor necrosis factor alpha (TNF-α) and C-reactive protein (CRP) up to 1 h after acute sprint exercise in the placebo-supplemented group. Malondialdehyde, lactate dehydrogenase (LDH), catalase, and superoxide dismutase enzymes also were increased after exercise in both groups. Red blood cell glutathione was lower after exercise in both groups. Cr supplementation reversed the increase in TNF-α and CRP as well as LDH induced by acute exercise. Controversially, Cr supplementation did not inhibit the rise in oxidative stress markers. Also, antioxidant enzyme activity was not different between placebo and Cr-supplemented groups. CONCLUSION Cr supplementation inhibited the increase of inflammation markers TNF-α and CRP, but not oxidative stress markers, due to acute exercise.

Bioactive compounds with effects on inflammation markers in humans.

Obesity and other chronic diseases are accompanied by adipose tissue, liver, pancreas, muscle and brain low-grade chronic inflammation. Indeed, the obese condition and metabolic syndrome are characterized by an increased expression of inflammatory cytokines and infiltration of immune cells in adipocytes. The inflammatory response promotes the activation of transcriptional factors and pro-inflammatory cytokines, which can lead to an unresolved inflammatory response associated with an inhibition of insulin signalling and high risk for cardiovascular events. Epidemiological and intervention studies have been carried out to find out dietary patterns, foods and bioactive compounds with protective anti-inflammatory actions. The most studied compounds are polyphenols, especially isoflavone and anthocyanin, but quercertin, catechin and resveratrol have also been investigated. Furthermore, some studies have reported the effects of milk peptides, plant sterol and stanol, l-carnitine and α-lipoic acid on inflammatory processes. This review aimed to collect and discuss those relevant studies reported in the scientific literature following a systematic scientific search about the effect of such bioactive compounds on inflammation in humans.

Evidence of zinc deficiency in competitive swimmers.

OBJECTIVE The aim of this study was to assess the nutritional zinc (Zn) status of elite swimmers during different training periods. METHODS A longitudinal paired study was performed at the University of Sao Paulo in eight male swimmers 18 to 25 y old who had been swimming competitively at the state and national levels for at least 5 y. The swimmers were evaluated over a total period of 14 wk: before the basic and specific preparatory period (BSPP-baseline), at the end of the basic and specific preparatory period (post-BSPP), and at the end of the polishing period (PP). Levels of Zn were determined in the plasma, erythrocyte, urine, and saliva by atomic absorption spectrophotometry. Anthropometric measurements and a 3-d food record were also evaluated. RESULTS The median plasma Zn concentration was below the reference value in all training periods (BSPP-baseline 59 μg/dL, post-BSPP 55.9 μg/dL, after PP 58.8 μg/dL, P > 0.05), as were threshold values for erythrocytes (BSPP-baseline 36.5 μg of Zn/g of hemoglobin, post-BSPP 42 μg of Zn/g of hemoglobin, after PP 40.7 μg of Zn/g of hemoglobin, P > 0.05), urinary Zn (BSPP-baseline 280 μg/24 h, post-BSPP 337 μg/24 h, after PP 284 μg/24 h, P > 0.05), and salivary Zn (BSPP-baseline 66.1 μg/L, post-BSPP 54.1 μg/L, after PP 79.7 μg/L, P > 0.05). Salivary Zn did not correlate with plasma and erythrocyte Zn levels. CONCLUSION The results suggest that the elite swimmers studied presented a possible Zn deficiency and that salivary Zn was not adequate to evaluate the Zn nutritional status.

Altered plasma response to zinc and iron tolerance test after Roux-en-Y gastric bypass

BACKGROUND The duodenum and proximal jejunum are excluded after Roux-en-Y gastric bypass but these intestinal sites are where iron and zinc are most absorbed. Therefore, they are among the nutrients whose digestive and absorptive process can be impaired after surgery. The aim of the present study was to investigate the iron and zinc plasma response to a tolerance test before and after bariatric surgery. The study was performed at São Paulo University School of Medicine of Ribeirão Preto, Brazil. METHODS In a longitudinal paired study, 9 morbidly obese women (body mass index ≥40 kg/m(2)) underwent an iron and zinc tolerance test before and 3 months after surgery. The iron and zinc levels were determined at 0, 1, 2, 3, and 4 hours after a physiologic unique oral dose. The mineral concentrations in the plasma and 24-hour urine sample were assayed using an atomic absorption spectrophotometer. The anthropometric measurements and 3-day food record were also evaluated. A linear mixed model was used to compare the plasma concentration versus interval after the oral dose, before and after surgery. RESULTS The pre- and postoperative test results revealed a significantly lower plasma zinc response (P <.01) and a delayed response to iron intake after surgery. The total plasma iron concentration area, during the 4 hours, was not different after surgery (P >.05). The 24-hour urinary iron and zinc excretion did not differ between the pre- and postoperative phases. CONCLUSION The present data showed a compromised response to the zinc tolerance test after gastric bypass surgery, suggesting an impaired absorption of zinc. More attention must be devoted to zinc nutritional status after surgery.

Calibration of the food list and portion sizes of a food frequency questionnaire applied to free-living elderly people

OBJECTIVE To calibrate the food list and relative portion sizes of a food frequency questionnaire (FFQ) for application to a free-living, healthy, elderly population. METHODS Cross-sectional study. One hundred free-living, healthy participants, aged from 60 to 75 y, randomly selected from among individuals in the area served by the Family Health Program, School of Medicine of Ribeirao Preto, University of São Paulo. A Food Frequency Questionnaire (FFQ) and a Diet History Questionnaire (DH) were applied by trained dietitians. Each food item of the FFQ had its portion size recalculated according to the percentiles referenced by the volunteers in the DH (25th = small, 50th = medium, and 75th = large). The list of foods and portion sizes of the original FFQ and those obtained by the application of the DH were compared. The percent contribution of energy, protein, fat, carbohydrate, folic acid, vitamin C, calcium, and fiber of each food item mentioned in the FFQ was determined from the data obtained by the application of the DH. RESULTS FFQ, as compared with the DH, provided good estimation of the intake of protein, calcium, folic acid, and fiber (paired t test P < 0.05). Portion sizes of the FFQ differed from those obtained by the application of the DH (-23% to 300%). CONCLUSIONS Adjustments to the FFQ in particular, new portion sizes and a reduction of the food list were found to be appropriate for application to healthy, urban, free-living elderly people in Ribeirao Preto, Brazil.

Creatine Supplementation Increases Total Body Water in Soccer Players: a Deuterium Oxide Dilution Study.

This study aimed to evaluate changes in total body water (TBW) in soccer athletes using a deuterium oxide dilution method and bioelectrical impedance (BIA) formulas after 7 days of creatine supplementation. In a double-blind controlled manner, 13 healthy (under-20) soccer players were divided randomly in 2 supplementation groups: Placebo (Pla, n=6) and creatine supplementation (CR, n=7). Before and after the supplementation period (0.3 g/kg/d during 7 days), TBW was determined by deuterium oxide dilution and BIA methods. 7 days of creatine supplementation lead to a large increase in TBW (2.3±1.0 L) determined by deuterium oxide dilution, and a small but significant increase in total body weight (1.0±0.4 kg) in Cr group compared to Pla. The Pla group did not experience any significant changes in TBW or body weight. Although 5 of 6 BIA equations were sensitive to determine TBW changes induced by creatine supplementation, the Kushner et al. 16 method presented the best concordance levels when compared to deuterium dilution method. In conclusion, 7-days of creatine supplementation increased TBW determined by deuterium oxide dilution or BIA formulas. BIA can be useful to determine TBW changes promoted by creatine supplementation in soccer athletes, with special concern for formula choice.

Taurine supplementation does not decrease homocysteine levels and liver injury induced by a choline-deficient diet.

AIMS The aim of this study is to examine the effects of taurine supplementation on homocysteine (Hcy) metabolism and liver injury in rats fed a choline-deficient diet. MAIN METHODS Thirty rats were divided into three groups (n=10), to receive one of the following diets for 4 weeks: control diet (C), choline-deficient diet (CDD), or choline-deficient diet supplemented with taurine (CDDT). The CDD and the CDDT consisted of AIN-93 without the recommended choline content of 2.5%, and the CDDT was supplemented by the addition of 2.5% taurine. KEY FINDINGS Four weeks of ingesting a CDD resulted in a significant increase in plasma Hcy (50%) as well as a decrease in liver S-adenosylmethionine (SAM) concentration and S-adenosylmethionine/S-adenosylhomocysteine ratio. No changes were found in plasma methionine and cysteine plasma levels compared to control group. Four weeks of ingesting a CDD also caused a significant (P<0.05) increase in hepatic total fat, hepatic malondialdehyde (MDA), and plasma alanine aminotransferase (ALT) levels. In addition, reduced hepatic glutathione (GSH) levels and reduced/oxidized glutathione ratios (GSH/GSSG) were found in rats fed a CDD compared to controls. Taurine supplementation of the CDD normalized genes involved in the remethylation pathway, BHMT and CHDH, which were impaired by CDD alone. However, taurine supplementation failed to prevent CDD-induced Hcy metabolism disturbances and hepatic injury. Also, taurine added to CDD caused decreased expression of PEMT, CHKa, and CHKb, key genes involved in phosphatidylcholine (PC) synthesis and liver fat accumulation. SIGNIFICANCE Taurine supplementation failed to ameliorate impaired Hcy metabolism and liver injury caused by CDD intake.

Amino acids in squamous cell carcinomas and adjacent normal tissues from patients with larynx and oral cavity lesions

Cancer patients experience metabolic disturbances that lead to nutritional status imbalance. The metabolic alterations of both host and tumor cells are predominantly caused by changes in the glucose metabolism of tumors, higher energy expenditures, decreases in ATP levels and increases in lactic acid production (1,2). Cellular amino acid contents appear to be essential for tumor growth. Theuer (3) observed that the restriction of tryptophan, threonine, leucine, methionine, phenylalanine, valine and isoleucine contributed to the control of tumor growth in rats. However, host weight was affected by tryptophan, threonine, leucine and methionine restriction. The restriction of phenylalanine and tyrosine also reduced weight, causing a loss of fat and lean body mass and an increase in white cells and neutrophils (4). Although it has been postulated that tumors utilize more amino acids than normal cells, few studies have compared the proportions of amino acids in tumor cells and paired normal tissues. Thus, the objective of the present study was to compare the amino acid content in malignant and adjacent normal tissues from the same patient.

Effect of combined training on body composition and metabolic variables in people living with HIV: A randomized clinical trial

Purpose The aim of this study was to conduct a randomized clinical trial to assess the effects of 16 weeks of combined training on body composition, lipid profile, adiponectin, C‐reactive protein (CRP), and leptin levels in people living with HIV/AIDS (PLWHA). Methods Fifty‐eight HIV‐infected individuals were randomized into a training group (T) or a control group (C). Combined training consisted of aerobic and resistance exercises performed at the same training session, applied at a frequency of three times a week for a total of 16 weeks. Waist circumference, body mass, body fat percentage (%fat), fat mass, lipid profile, adiponectin, CRP, and leptin levels were measured pre‐ and post‐training in both groups. Results Sixteen weeks of combined training decreased (P < 0.05) body fat in different body segments in PLWHA. Lipodystrophic PLWHA experienced greater reduction in body fat in the android region than non‐lipodystrophic PLWHA after combined training. Lipid profile and circulating levels of adiponectin, leptin, and CRP remained unchanged. Conclusions Sixteen weeks of combined training was effective to reduce body fat in different body segments, without altering plasma lipid and cytokine levels. HighlightsCombined training was beneficial for body composition HIV‐infected people.Combined training did not modify lipid profile and cytokines levels.Reduction of body fat was not accompanied by metabolic changes.Patients with lipodystrophy showed reduction of android fat when compared to non‐lipodystrophic. Graphical abstract Figure. No caption available.