Raul Osiecki

Decreased erythrocyte NA+,K+-ATPase activity and increased plasma TBARS in prehypertensive patients.

The essential hypertension has been associated with membrane cell damage. The aim of the present study is investigate the relationship between erythrocyte Na+,K+-ATPase and lipoperoxidation in prehypertensive patients compared to normotensive status. The present study involved the prehypertensive patients (systolic: 136 ± 7 mmHg; diastolic: 86.8 ± 6.3 mmHg; n = 8) and healthy men with normal blood pressure (systolic: 110 ± 6.4 mmHg; diastolic: 76.1 ± 4.2 mmHg; n = 8) who were matched for age (35 ± 4 years old). The venous blood samples of antecubital vein (5 mL) were collected into a tube containing sodium heparin as anticoagulant (1000 UI), and erythrocyte ghosts were prepared for quantifying Na+,K+-ATPase activity. The extent of the thiobarbituric acid reactive substances (TBARS) was determined in plasma. The statistical analysis was carried out by Students t-test and Pearsons correlation coefficient. A P < 0.05 was considered significant. The Na+,K+-ATPase activity was lower in prehypertensive patients compared with normotensive subjects (4.9 versus 8.0 nmol Pi/mg protein/min; P < 0.05). The Na+,K+-ATPase activity correlated negatively with TBARS content (r = −0.6; P < 0.05) and diastolic blood pressure (r = −0.84; P < 0.05). The present study suggests that Na+,K+-ATPase activity reduction and elevation of the TBARS content may underlie the pathophysiological aspects linked to the prehypertensive status.

Gender-dependent association of HSD11B1 single nucleotide polymorphisms with glucose and HDL-C levels

In this study, we investigated the influence of two SNPs (rs846910 and rs12086634) of the HSD11B1 gene that encodes 11β-hydroxysteroid dehydrogenase type 1(11β-HSD1), the enzyme that catalyzes the conversion of cortisol to cortisone, on variables associated with obesity and metabolic syndrome in 215 individuals of both sexes from southern Brazil. The HSD11B1 gene variants were genotyped using the TaqMan SNP genotyping assay. Glucose, triglycerides, total cholesterol, HDL-cholesterol and LDL-cholesterol were measured by standard automated methods. Significant results were found in women, with carriers of the G allele of SNP rs12086634 having higher glucose levels than non-carriers. Carriers of the A allele of SNP rs846910 had higher levels of HDL-cholesterol. The involvement of both polymorphisms as independent factors in determining the levels of glucose and HDL-cholesterol was confirmed by multiple regression analysis (β = 0.19 ±0.09, p = 0.03 and β= 0.22 ± 0.10, p = 0.03, respectively). Our findings suggest that the HSD11B1SNPs studied may indirectly influence glucose and HDL-cholesterol metabolism in women, possibly through down-regulation of the HSD11B1 gene by estrogen.

Effect of a Reduced-CHO Diet on the Rate of Perceived Exertion Curve During an Incremental Test

The objective of this study was to evaluate the effect of a reduced-carbohydrate (reduced-CHO) diet on the rate of perceived exertion (RPE) curve during an incremental test. Nine physically active men performed a progressive incremental test on a cycle ergometer (25 W · 2 min(-1)) after 72 hr on either a control diet (60% CHO) or a reduced-CHO diet (30% CHO). Lactate and RPE thresholds were identified using the Dmax method (DmaxLa and DmaxRPE, respectively). Power output, heart rate and RPE scores in DmaxLa and DmaxRPE were similar between the diets and were not different from each other, regardless of the diet. Lactate values were consistently higher (p < .05) in the control diet compared with the reduced-CHO diet during power output after the lactate breakpoint; however, they were not accompanied by a proportional increase in RPE scores. These results suggest that DmaxRPE and DmaxLa are not dissociated after a short-period reduced-CHO diet, whereas the lactate values after the lactate threshold are reduced with a reduced-CHO diet, although they are not accompanied by alterations in RPE.

Resposta da frequência cardíaca e da concentração de lactato após cada segmento do triathlon olímpico

INTRODUCTION: The physiological responses of each part of Triathlon are different; better training loads could be prescribed for athletes considering each segment of this sport. OBJECTIVE: The purpose of this study was to investigate the behavior of physiological variables - heart rate and blood lactate concentration - before the event, after each segment of an Olympic Triathlon: swimming, cycling and running, and after recovery time. METHODS: The sample included twelve male triathletes who participated in a triathlon event with Olympic distance. Capillary blood samples were taken from the fingertip in the beginning of the event (pre-event), after each segment (swimming, cycling, running) and after 1 hour of recovery. Each athlete was monitored during the entire event by a heart rate monitor (Polar® S610). Statistical procedures included: Spearman correlations and Wilcoxon non parametric tests (p<0.05). RESULTS: The study results showed that the highest intensity was reached during cycling (HRmax: 86.3%; Lac: 6.98 mmol/L) in both physiological parameters, followed by swimming (HRmax: 85.2%, Lac: 5.75 mmol/L) and running (HRmax: 83.6%, lac: 4.47mmol), respectively. CONCLUSIONS: Training load prescription based on different physiological markers responses - such as heart rate and blood lactate concentration - of each triathlon segment will be more efficient for the Olympic triathlon demands.

Protocolo de reabilitação acelerada após reconstrução de ligamento cruzado anterior - dados normativos

OBJECTIVE evaluate the gotten results of the accelerated protocol adapted to the clinic conditions in CLA post operatory patients. METHODS 30 patients were selected and submitted to an isokynetic test at the pre operatory and 4 months post operatory. RESULTS the isokinetics evaluations at the pre operatory presented: flexor peak torque 93% at 60 degrees /s and 97,3% at 180 degrees /s. Extensor 87,3% at 60 degrees /s and 94,7% at 180 degrees /s; power of the flexor muscles of 93,3% and extensors of 96,7%; the muscular work of the flexors was of 91,7% and extensors of 90,3%; the flexor peak torque angle was at 28,7 degrees . At the extensor musculature the angle was at 62,2 degrees ; flexors eccentric peak torque of 78,3% and the extensors of 12,8%. With 4 months of post operatory the gotten results showed: flexor peak torque 95,4% at 60 degrees /s and 97,1%. at 180 degrees /s; extensor 70% at 60 degrees /s and 75,7%. at 180 degrees /s; power of the flexor muscles of 97,1% and extensors of 79,8%; the muscular work of the flexors was of 94,2% and extensors of 94,2%; flexors eccentric peak torque of 84% and extensors of 24,2%; the flexor peak torque angle was at 27,3 degrees ; in extensor musculature the angle was at 61,7 degrees . CONCLUSION showed that the patients treated with the adapted protocol presented similar results to the original protocol in relation to the muscular conditions.

ADIPOQ single nucleotide polymorphism: Association with adiponectin and lipoproteins levels restricted to men.

Adiponectin is an adipokine inversely correlated with obesity, which has beneficial effect on insulin resistance and lipid metabolism. Considering its potential as a therapeutic target in the metabolic disorder contexts, and in order to add knowledge in the area, our study evaluated the ADIPOQ 276G > T polymorphism effect on adiponectin levels, and on lipoproteins of clinical interest in a population sample composed of 211 healthy individuals. Significant effects were observed only among men: the carriers of heterozygous genotype (GT) showed high levels of adiponectin (p = 0.018), while the rare homozygous genotype (TT) gave its carriers a negative phenotype, represented by higher levels of low density lipoprotein cholesterol (LDL-C) (p = 0.004 and p = 0.005) and total cholesterol (TC) (p = 0.010 and p = 0.005) compared to carriers of other genotypes (GG and GT respectively), the independent effect of SNP on LDL-C and TC levels was confirmed by multiple regression analysis (p = 0.008 and p = 0.044). We found no evidence of correlation between circulating adiponectin levels and biochemical markers, which suggests, therefore, an SNP 276G > T independent effect on adiponectin levels and on lipoprotein metabolism in men enrolled in this study.

Physiological, Perceptual, and Affective Responses to Six High-Intensity Interval Training Protocols:

This study examined the extent to which different high-intensity interval training (HIIT) and sprint interval training (SIT) protocols could influence psychophysiological responses in moderately active young men. Fourteen participants completed, in a randomized order, three cycling protocols (SIT: 4 × 30-second all-out sprints; Tabata: 7 × 20 seconds at 170% ⋮O2max; and HIIT: 10 × 60 seconds at 90% HRmax) and three running HIIT protocols (4 × 4 minutes at 90%–95% HRmax, 5 × at v⋮O2max, and 4 × 1,000 meters at a rating of perceived exertion (RPE) of 8, from the OMNI-Walk/Run scale). Oxygen uptake (⋮O2), heart rate, and RPE were recorded during each interval. Affective responses were assessed before and after each trial. The Tabata protocol elicited the highest ⋮O2 and RPE responses, and the least pleasant session-affect among the cycling trials. The v⋮O2max elicited the highest ⋮O2 and RPE responses and the lowest mean session-affect among the running trials. Findings highlight the limited application of SIT and some HIIT protocols to individuals with low fitness levels.

Efeito da suplementação aguda com cafeína na resposta bioquímica durante exercício de endurance em ratos

Introduccion:La cafeina es actualmente la sustancia de mayor consumo en el mundo, y combinado con el ejercicio fisico, ha traido beneficios importantes en el rendimiento durante el ejercicio.Objetivo:Investigar los efec-tos bioquimicos da la suplementacion aguda de cafeina despues de un ejercicio de endurance en ratones Wistar.Metodos:Fueron utilizados 27 ratones Wistar machos, con 357 ± 73 g de peso corporal, distribuidos de forma alea-toria en tres grupos: 1) Control (sin suplementacion y ejercicio); 2) Salina (salina + ejercicio); 3) Cafeina (6 mg/Kg de cafeina + ejercicio). Las suplementaciones les fueran administradas 50 minutos antes de la natacion con duracion de 60 minutos. Despues de la natacion, los animales fueron sacrificados para la extraccion de sangre y biopsia de tejido hepatico y muscular. Fueron analizados los niveles de glucosa sanguinea, trigliceridos, lactato serico y concentraciones de glucogeno hepatico y muscular. Todos los resultados fueron representados como media ± EPM. Para la analisis estadistica se aplico la prueba ANOVA one way, siendo considerada diferencia estadistica solo para P<0,05.Resultados:Lo glucogeno muscular y el lactato no difirieron entre los grupos. La cafeina preservo los niveles de glucosa sanguinea y glucogeno hepatico (P<0,05). La cafeina elevo los niveles de glicerol plasmatico en 31,2% (P<0,05) en comparacion con el grupo ejercitado sin suplementacion.Conclusion:El estudio reporta que el uso de la cafeina antes del ejercicio promueve alteraciones bioquimicas que pueden mejorar la eficiencia metabolica durante el ejercicio de endurance.

Sulfonylurea induction of caffeine-enhanced insulin secretion and reduction of glycemic levels in diabetic rats

Abstract Context: Caffeine can stimulate insulin secretion by attenuating hyperglycemia in diabetes models with significant reduction of pancreatic functional β cells. Knowledge of these mechanisms could contribute to new strategies for treating diabetes. Objective: This study evaluated the effects of caffeine and physical exercise on glycemic and insulin responses in diabetic rats. Materials and methods: The diabetes model was induced by intraperitoneal administration of 60 mg/kg of streptozotocin (STZ). Animals were divided into six groups: control, caffeine, STZ control, STZ caffeine, STZ sulfonylurea, and STZ caffeine + sulfonylurea. Acutely, control animals received 6 mg of caffeine and 10 mg/kg sulfonylurea or 10 mg/kg saline. Animals were sacrificed after physical exercise; blood samples were collected for glucose, glycerol, lactate, and insulin analyses. Cardiovascular responses were recorded before and after treatments. A one-way ANOVA and the post hoc Student–Newman–Keuls test were used to analyze statistical differences between treatments (p < 0.05). Results: About 6 mg/kg of caffeine did not alter cardiovascular responses, but promoted blood glucose reduction after 60 min of exercise when compared to animals in the control groups (387–187 mg/dL; p < 0.05). Insulin levels increased significantly (0.6–10 µU/mL; p < 0.05) in rats that received acute caffeine treatment associated with sulfonylurea compared to rats in the other groups. Discussion and conclusion: Acute caffeine intake with exercise can increase glucose uptake enhancing insulin secretion stimulated by sulfonylurea in β cells-deficient pancreas. The results indicate the potential use of caffeine as a strategy for glycemic and insulin control in diabetes.

VARIÁVEIS PSICOLÓGICAS ASSOCIADAS À SÍNDROME DE BURNOUT E DESEMPENHO EM ATLETAS ADULTOS ATRAVÉS DO ATHLETE BURNOUT QUESTIONNAIRE - ABQ

Recently, scholars have been sought to deepen research on a psycho-physiological phenomenon that can lead athletes to quit sports, known in the literature as sport-related burnout. The aim of the present integrative review study was to analyze psychological and performance variables associated with the burnout syndrome in adult athletes. Articles were searched on Pubmed, Web of Science, Scielo, Science Direct, Scopus and Apapsycnet electronic databases, using the following descriptors: burnout, sports and athletes, in both English and Portuguese. From the 15 selected studies, there was predominance of psychological variables associated with burnout over performance aspects. Negative correlations were found between burnout and basic psychological needs, intrinsic motivation and coping strategies. Positive correlations were found between burnout and competitive level, training volume, years of training, perfectionism and overtraining. There were no data on performance increase or decrease related to burnout in adult high-performance athletes, which shows a gap in the literature and encourages new investigations.