Endotoxin levels correlate positively with a sedentary lifestyle and negatively with highly trained subjects

Introduction: A sedentary lifestyle increases the risk of developing cardiovascular disease, obesity, and diabetes. This phenomenon is supported by recent studies suggesting a chronic, low-grade inflammation status. Endotoxin derived from gut flora may be key to the development of inflammation by stimulating the secretion of inflammatory factors. This study aimed to examine plasma inflammatory markers and endotoxin levels in individuals with a sedentary lifestyle and/or in highly trained subjects at rest. Methods: Fourteen male subjects (sedentary lifestyle n = 7; highly trained subjects n = 7) were recruited. Blood samples were collected after an overnight fast (similar to 12 h). The plasmatic endotoxin, plasminogen activator inhibitor type-1 (PAI-1), monocyte chemotactic protein-1 (MCP1), ICAM/CD54, VCAM/CD106 and lipid profile levels were determined. Results: Endotoxinemia was lower in the highly trained subject group relative to the sedentary subjects (p < 0.002). In addition, we observed a positive correlation between endotoxin and PAI-1 (r = 0.85, p < 0.0001), endotoxin and total cholesterol (r = 0.65; p < 0.01), endotoxin and LDL-c (r = 0.55; p < 0.049) and endotoxin and TG levels (r = 0.90; p < 0.0001). The plasma levels of MCP-1, ICAM/CD54 and VCAM/CD106 did not differ. Conclusion: These results indicate that a lifestyle associated with high-intensity and high-volume exercise induces favorable changes in chronic low-grade inflammation markers and may reduce the risk for diseases such as obesity, diabetes and cardiovascular diseases.

Sex and socioeconomic inequalities of lung cancer mortality in Barcelona, Spain and Sao Paulo, Brazil

The objective of this paper was to assess sex and socioeconomic inequalities in lung cancer mortality in two major cities of Europe and South America. Official information on mortality and population allowed the estimation of sex- and age-specific death rates for Barcelona, Spain and Sao Paulo, Brazil (1995-2003). Mortality trends and levels were independently assessed for each city and subsequently compared. Rate ratios assessed by Poisson regression analysis addressed hypotheses of association between the outcome and socioeconomic covariates (human development index, unemployment and schooling) at the inner-city area level. Barcelona had a higher mortality in men (76.9/100000 inhabitants) than Sao Paulo (38.2/100 000 inhabitants); although rates were decreasing for the former (-2%/year) and levelled-off for the [after. Mortality in women ranked similarly (9.1 for Barcelona, 11.5 for Sao Paulo); with an increasing trend for women aged 35-64 years (+ 7.7%/year in Barcelona and + 2.4%/year in Sao Paulo). The socioeconomic gradient of mortality in men was negative for Barcelona and positive for Sao Paulo; for women, the socioeconomic gradient was positive in both cities. Negative gradients indicate that deprived areas suffer a higher burden of disease; positive gradients suggest that prosmoking lifestyles may have been more prevalent in more affluent areas during the last decades. Sex and socioeconomic inequalities of lung cancer mortality reinforce the hypothesis that the epidemiologic profile of cancer can be improved by an expanded access to existing technology of healthcare and prevention. The continuous monitoring of inequalities in health may contribute to the concurrent promotion of well-being and social justice.

Trends in Morbid Obesity and in Bariatric Surgeries Covered by the Brazilian Public Health System

Obesity is an increasingly serious public health problem on a global level. Morbid obesity, defined as a body mass index greater than 40 kg/m(2), is associated with increased mortality and a high burden of obesity-related morbidities. To study the prevalence of morbid obesity in Brazil, three national anthropometric surveys were reanalyzed. Data about bariatric surgeries were obtained from the Ministry of Health Hospital Information System, which is available online. A 255% rise in the prevalence of morbid obesity was observed, starting at 0.18% in 1975-1976 and growing to 0.33% in 1989 and 0.64% in 2002-2003. There was a higher rate in the South in the first two surveys, but the prevalence in the Southeast rose steadily, reaching 0.77% in 2002-2003 and overtaking the South. Since 1999, the Brazilian Unified Health System has covered surgical treatment for morbid obesity. From 2000 to 2006, there was a sixfold increase in the number of surgeries, which topped the 2,500 mark in 2006. The geographic distribution of these surgeries is heavily concentrated in the Southeast, the most developed region of Brazil, where there is also the highest prevalence of morbid obesity. This was followed by the Southern region. The figures for the rise in morbid obesity in Brazil are startling, especially the increase among men. This is a situation that calls for further study, alongside measures to encourage the adoption of healthy lifestyles. Preventive measures aimed at slowing down or reversing the obesity epidemic are urgently required.

Clinical risk factors for osteoporotic fractures in Brazilian women and men: the Brazilian Osteoporosis Study (BRAZOS)

The Brazilian Osteoporosis Study (BRAZOS) is the first epidemiological study carried out in a representative sample of Brazilian men and women aged 40 years or older. The prevalence of fragility fractures is about 15.1% in the women and 12.8% in the men. Moreover, advanced age, sedentarism, family history of hip fracture, current smoking, recurrent falls, diabetes mellitus and poor quality of life are the main clinical risk factors associated with fragility fractures. The Brazilian Osteoporosis Study (BRAZOS) is the first epidemiological study carried out in a representative sample of Brazilian men and women aged 40 years or older with the purpose of identifying the prevalence and the main clinical risk factors (CRF) associated with osteoporotic fracture in our population. A total of 2,420 individuals (women, 70%) from 150 different cities in the five geographic regions in Brazil, and all different socio-economical classes were selected to participate in the present survey. Anthropometrical data as well as life habits, fracture history, food intake, physical activity, falls and quality of life were determined by individual quantitative interviews. The representative sampling was based on Brazilian National data provided by the 2000 and 2003 census. Low trauma fracture was defined as that resulting of a fall from standing height or less in individuals 50 years or older at specific skeletal sites: forearm, femur, ribs, vertebra and humerus. Sampling error was 2.2% with 95% confidence intervals. Logistic regression analysis models were designed having the fragility fracture as the dependent variable and all other parameters as the independent variable. Significance level was set as p < 0.05. The average of age, height and weight for men and women were 58.4 +/- 12.8 and 60.1 +/- 13.7 years, 1.67 +/- 0.08 and 1.56 +/- 0.07 m and 73.3 +/- 14.7 and 64.7 +/- 13.7 kg, respectively. About 15.1% of the women and 12.8% of the men reported fragility fractures. In the women, the main CRF associated with fractures were advanced age (OR = 1.6; 95% CI 1.06-2.4), family history of hip fracture (OR = 1.7; 95% CI 1.1-2.8), early menopause (OR = 1.7; 95% CI 1.02-2.9), sedentary lifestyle (OR = 1.6; 95% CI 1.02-2.7), poor quality of life (OR = 1.9; 95% CI 1.2-2.9), higher intake of phosphorus (OR = 1.9; 95% CI 1.2-2.9), diabetes mellitus (OR = 2.8; 95% CI 1.01-8.2), use of benzodiazepine drugs (OR = 2.0; 95% CI 1.1-3.6) and recurrent falls (OR = 2.4; 95% CI 1.2-5.0). In the men, the main CRF were poor quality of life (OR = 3.2; 95% CI 1.7-6.1), current smoking (OR = 3.5; 95% CI 1.28-9.77), diabetes mellitus (OR = 4.2; 95% CI 1.27-13.7) and sedentary lifestyle (OR = 6.3; 95% CI 1.1-36.1). Our findings suggest that CRF may contribute as an important tool to identify men and women with higher risk of osteoporotic fractures and that interventions aiming at specific risk factors (quit smoking, regular physical activity, prevention of falls) may help to manage patients to reduce their risk of fracture.

Exercise improves cardiovascular control in a model of dislipidemia and menopause

The present study investigated the effects of exercise training on arterial pressure, baroreflex sensitivity, cardiovascular autonomic control and metabolic parameters on female LDL-receptor knockout ovariectomized mice. Mice were divided into two groups: sedentary and trained. Trained group was submitted to an exercise training protocol. Blood cholesterol was measured. Arterial pressure (AP) signals were directly recorded in conscious mice. Baroreflex sensitivity was evaluated by tachycardic and bradycardic responses to AP changes. Cardiovascular autonomic modulation was measured in frequency (FFT) and time domains. Maximal exercise capacity was increased in trained as compared to sedentary group. Blood cholesterol was diminished in trained mice (191 +/- 8 mg/dL) when compared to sedentary mice (250 +/- 9 mg/dL, p<0.05). Mean AP and HR were reduced in trained group (101 +/- 3 mmHg and 535 +/- 14 bpm, p<0.05) when compared with sedentary group (125 +/- 3 mmHg and 600 +/- 12 bpm). Exercise training induced improvement in bradycardic reflex response in trained animals (-4.24 +/- 0.62 bpm/mmHg) in relation to sedentary animals (-1.49 +/- 0.15 bpm/mmHg, p<0.01); tachycardic reflex responses were similar between studied groups. Exercise training increased the variance (34 +/- 8 vs. 6.6 +/- 1.5 ms(2) in sedentary, p<0.005) and the high-frequency band (HF) of the pulse interval (IP) (53 +/- 7% vs. 26 +/- 6% in sedentary, p<0.01). It is tempting to speculate that results of this experimental study might represent a rationale for this non-pharmacological intervention in the management of cardiovascular risk factors in dyslipidemic post-menopause women. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Effects of exercise training on autonomic dysfunction management in an experimental model of menopause and myocardial infarction

Objective: The aim of this study was to investigate the effects of exercise training on cardiovascular autonomic dysfunction in ovariectomized rats submitted to myocardial infarction. Methods: Female Wistar rats were divided into the following ovariectomized groups: sedentary ovariectomized (SO), trained ovariectomized (TO), sedentary ovariectomized infarcted (SOI), and trained ovariectomized infarcted (TOI). Trained groups were submitted to an exercise training protocol on a treadmill (8 wk). Arterial baroreflex sensitivity was evaluated by heart rate responses to arterial pressure changes, and cardiopulmonary baroreflex sensitivity was tested by bradycardic and hypotension responses to serotonin injection. Vagal and sympathetic effects were calculated by pharmacological blockade. Results: Arterial pressure was reduced in the TO in comparison with the SO group and increased in the TOI in relation to the SOI group. Exercise training improved the baroreflex sensitivity in both the TO and TOI groups. The TOI group displayed improvement in cardiopulmonary reflex sensitivity compared with the SOI group at the 16 mu g/kg serotonin dose. Exercise training enhanced the vagal effect in both the TO (45%) and TOI (46%) animals compared with the SO and SOI animals and reduced the sympathetic effect in the TOI (38%) in comparison with the SOI animals. Significant correlations were obtained between bradycardic baroreflex responses and vagal (r = -0.7, P < 0.005) and sympathetic (r = 0.7, P < 0.001) effects. Conclusions: These results indicate that exercise training in ovariectomized rats submitted to myocardial infarction improves resting hemodynamic status and reflex control of the circulation, which may be due to an increase in the vagal component. This suggests a homeostatic role for exercise training in reducing the autonomic impairment of myocardial infarction in postmenopausal women.

The evolution of jumping performance in anurans: morphological correlates and ecological implications

We investigated the evolution of anuran locomotor performance and its morphological correlates as a function of habitat use and lifestyles. We reanalysed a subset of the data reported by Zug (Smithson. Contrib. Zool. 1978; 276: 1-31) employing phylogenetically explicit statistical methods (n = 56 species), and assembled morphological data on the ratio between hind-limb length and snout-vent length (SVL) from the literature and museum specimens for a large subgroup of the species from the original paper (n = 43 species). Analyses using independent contrasts revealed that classifying anurans into terrestrial, semi-aquatic, and arboreal categories cannot distinguish between the effects of phylogeny and ecological diversification in anuran locomotor performance. However, a more refined classification subdividing terrestrial species into `fossorials` and `non-fossorials`, and arboreal species into `open canopy`, `low canopy` and `high canopy`, suggests that part of the variation in locomotor performance and in hind-limb morphology can be attributed to ecological diversification. In particular, fossorial species had significantly lower jumping performances and shorter hind limbs than other species after controlling for SVL, illustrating how the trade-off between burrowing efficiency and jumping performance has resulted in morphological specialization in this group.

Exercise changes the size of cardiac neurons and protects them from age-related neurodegeneration

Aging leads to changes in cardiac structure and function. Evidence suggests that the practice of regular exercise may prevent disturbances in the cardiovascular system during aging. We studied the effects of aging on the morphology and morphometry of cardiac neurons in Wistar rats and investigated whether a lifelong moderate exercise program could exert a protective effect toward some deleterious effects of aging. Aging caused a significant decline (28%) in the number of NADH-diaphorase-stained cardiac Animals submitted to a daily session of 60 min, 5 day/week, at 1.1 km/h of running in treadmill over the entire life span exhibited a reversion of the observed decline in the number of cardiac neurons. However, most interesting was that the introduction of this lifelong exercise protocol dramatically altered the sizes of cardiac neurons. There was a notable increase in the percentage of small neurons in the rats of the exercise group compared to the sedentary animals. This is the first time that a protective effect of lifelong regular aerobic exercise has been demonstrated on the deleterious effects of aging in cardiac neurons. (C) 2009 Elsevier GmbH. All rights reserved.

Exercise reduces inhibitory neuroactivity and protects myenteric neurons from age-related neurodegeneration

The practice of regular exercise is indicated to prevent some motility disturbances in the gastrointestinal tract, such as constipation, during aging. The motility alterations are intimately linked with its innervations. The goal of this study is to determine whether a program of exercise (running on the treadmill), during 6 months, has effects in the myenteric neurons (NADH- and NADPH-diaphorase stained neurons) in the colon of rats during aging. Male Wister rats 6 months (adult) and 12 months (middle-aged) old were divided into 3 different groups: AS (adult sedentary), MS (middle-aged sedentary) and MT (middle-aged submitted to physical activity). The aging did not cause a decline significant (p > 0.05) of the number of NADH-diaphorase stained neurons in sedentary rats (AS vs. MS group). In contrast, a decline of 3 1% was observed to NADPH-diaphorase stained neurons. Thus, animals that underwent physical activity (AS vs. MT group) rescued neurons from degeneration caused by aging (total number, density and profile of neurons did not change with age - NADH-diaphorase method). On the other hand, physical activity augmented the decline of NADPH-diaphorase positive neurons (total number, density and profile of neurons decreased). Collectively, the results show that exercise inhibits age-related decline of myenteric neurons however, exercise augments the decline of neurons with inhibitory activity (nitric oxide) in the colon of the rats. (c) 2008 Elsevier B.V. All rights reserved.

Effects of exercise on the morphology of the myenteric neurons of the duodenum of Wistar rats during the ageing process

This study aimed to evaluate the effects of regular physical activity on the morphology of the myenteric plexus of the duodenum in rats during the ageing process. To this end, 45 Wistar rats were divided into three groups: C (sedentary - 6 months old), S (sedentary - 12 months old) and T (trained - 12 months old). The animals of group S were given with a physical activity programme consisting of a 10-min-treadmill workout once a week. The animals of group T were submitted to the physical activity programme five times a week. Their duodenums were collected and submitted to the techniques of nicotinamide adenine dinucleotide (NADH)-diaphorase enzyme histochemistry for whole-mount preparations and transmission electron microscopy. No differences in the constitution of the myenteric plexuses were found when the sedentary and trained groups were compared with the control group. The ultrastructural features were similar for the three groups. However, it was verified that the physical activity of the trained animals resulted in a similar myenteric neuron morphology to that of the adult animals (6 months old), thereby confirming its beneficial effect, as the sedentary animals had larger alterations in the collagen fibrils and the basal membrane that occur through ageing. The quantitative analysis showed that the NADH-diaphorase positive neurons decreased with ageing and increased with physical activity (P > 0.05). No significant alteration (P > 0.05) in the neuronal profile area of the NADH-diaphorase positive neurons has been observed with ageing.

Lymphocyte and Cytokines after Short Periods of Exercise

The purpose of this study was to verify the effects of short periods of exercise of different intensity on lymphocyte function and cytokines. Thirty Wistar rats, 2 months old, were used. They were divided into five groups of six rats: a sedentary control group; a group exercised for 5 minutes at low intensity (5 L): a group exercised for 15 minutes at low intensity (15 L); and groups exercised at moderate intensity (additional load of 5% of body weight) for 5 minutes (5 M) or for 15 minutes (15 M). The parameters measured were: total leukocytes, neutrophils, lymphocytes, monocytes, lymphocytes from lymph nodes, serum cytokines (IL-2, IL-6 and TNF-alpha), lymphocyte mitochondrial transmembrane potential, viability and DNA fragmentation. ANOVA two way followed by Tukey`s post hoc test (p <= 0.05) was used. The exercised groups exhibited a significant increase in total leukocytes, tissue and circulating lymphocytes in comparison with the control group. There was a significant decrease in lymphocyte viability and decrease in DNA fragmentation for the 15 M group when compared with the control. There was a decrease in the level TNF-alpha in the 5 M and 15 M groups. Short-term, low- and moderate-intensity exercise may be considered for sedentary individuals beginning to exercise, since no deleterious alterations were observed in lymphocyte function.

Is gender crucial for cardiovascular adjustments induced by exercise training in female spontaneously hypertensive rats?

Evidence of mild hypertension in women and female rats and our preliminary observation showing that training is not effective to reduce pressure in female as it does in male spontaneously hypertensive rats (SHR) prompt us to investigate the effects of gender on hemodynamic pattern and microcirculatory changes induced by exercise training. Female SHR and normotensive controls (Wistar- Kyoto rats) were submitted to training (55% VO2 peak; 3 months) or kept sedentary and instrumented for pressure and hindlimb flow measurements at rest and during exercise. Heart, kidney, and skeletal muscles (locomotor/ nonlocomotor) were processed for morphometric analysis of arterioles, capillaries, and venules. High pressure in female SHR was accompanied by an increased arteriolar wall: lumen ratio in the kidney (+30%; P < 0.01) but an unchanged ratio in the skeletal muscles and myocardium. Female SHR submitted to training did not exhibit further changes on the arteriolar wall: lumen ratio and pressure, showing additionally increased hindlimb resistance at rest (+29%; P < 0.05). On the other hand, female SHR submitted to training exhibited increased capillary and venular densities in locomotor muscles (+50% and 2.3- fold versus sedentary SHR, respectively) and normalized hindlimb flow during exercise hyperemia. Left ventricle pressure and weight were higher in SHR versus WKY rats, but heart performance (positive dP/dt(max) and negative dP/dt(max)) was not changed by hypertension or training, suggesting a compensated heart function in female SHR. In conclusion, the absence of training- induced structural changes on skeletal muscle and myocardium arterioles differed from changes observed previously in male SHR, suggesting a gender effect. This effect might contribute to the lack of pressure fall in trained female SHRs.

Neutrophil death induced by a triathlon competition in elite athletes

Introduction/Purpose: The effect of a triathlon competition on death of neutrophils from elite athletes was investigated. Methods: Blood was collected from 11 sedentary volunteers and 12 triathletes under rest and after a Half Ironman triathlon competition (2-km swimming, 80-km cycling, and 20-km running). Results: The triathlon competition increased DNA fragmentation, phosphatidylserine externalization, and reactive oxygen species production in neutrophils when compared to the results at rest. The proportion of neutrophils with mitochondrial transmembrane depolarization was increased in the triathletes at rest and after competition as compared with sedentary volunteers. Plasma levels of thiobarbituric acid reactive substances were increased in triathletes after competition. Expression of bcl-xL (antiapoptotic) was decreased and that of bax (proapoptotic) was increased, whereas intracellular neutral lipid content was lowered in neutrophils after the triathlon. A positive correlation was found between the proportion of neutrophils with DNA fragmentation and the plasma free fatty acid levels (r = 0.688, P < 0.05), which was elevated by threefold after competition. Plasma levels of oleic, linoleic, and stearic acids were increased in triathletes after the competition when compared with sedentary volunteers. The plasma concentration of these three fatty acids, measured after the triathlon competition, was toxic for 3-h cultured neutrophils obtained from sedentary volunteers. The maximal tolerable (nontoxic) concentration of the fatty acids by 3-h cultured neutrophils was 100 mu mol.L-1 for oleic and linoleic acids and 200 mu mol.L-1 for stearic acid. Conclusion: The triathlon competition induced neutrophil death possibly by apoptosis as indicated by DNA fragmentation and phosphatidylserine externalization. The increase in plasma levels of oleic, linoleic, and stearic acids induced by the competition may be involved in the neutrophil death observed possibly by increasing the production of reactive oxygen species and by decreasing the accumulation of intracellular neutral lipid.

Exercise-stimulated GLUT4 Expression is Similar in Normotensive and Hypertensive Rats

The effects of exercise training on systolic blood pressure (BP), insulin sensitivity, and plasma membrane GLUT4 protein content in spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto (WKY) rats were compared. 16 SHR and 16 WKY male rats, aged 6 months, were randomized into sedentary and trained (tread-mill running, 5 days/week, 60 min/day for 10 weeks) groups (n = 8/group). At baseline, SHR had lower insulin sensitivity than WKY rats, however, there were no differences between WKY and SHR GLUT4 expression. The 10-week training reduced BP by similar to 19% in SHR, improved insulin sensitivity by similar to 24% in SHR, but not in WKY, and increased GLUT4 expression in both animal models. Compared to the sedentary group, there was an increase of GLUT4 in WKY rats by similar to 25% in the heart, by similar to 23% in the gastrocnemius, and by similar to 15% in the fat tissue. Trained SHR presented an increase in GLUT4 of similar to 21%, similar to 20%, and similar to 14%, in the same tissues, respectively. There were no differences between SHR and WKY rats in post-training GLUT4 expression. We conclude that training determined BP and insulin resistance reduction in SHR, and increased GLUT4 expression in both normotensive and hypertensive rats. However, considering the similar rise in GLUT4-induced training in SHR and WKY, it is possible that GLUT4 levels in plasma membrane fraction do not have a pivotal role in the exercise-induced improvement of insulin sensitivity in SHR.

Exercise-induced plasticity of AMPA-type glutamate receptor subunits in the rat brain

The aim of this study was to analyze the plastic effects of moderate exercise upon the motor cortex (M1 and M2 areas), cerebellum (Cb), and striatum (CPu) of the rat brain This assessment was made by verifying the expression of AMPA type glutamate receptor subunits (GluR1 and GluR2/3) We used adult Wistar rats, divided into 5 groups based on duration of exercise training, namely 3 days (EX3), 7 days (EX7) 15 days (EX15) 30 days (EX30), and sedentary (S) The exercised animals were subjected to a treadmill exercise protocol at the speed of the 10 meters/min for 40 mm After exercise, the brains were subjected to immunohistochemistry and immunoblotting to analyze changes of GluR1 and GluR2/3, and plasma cortcosterone was measured by ELISA in order to verify potential stress induced by physical training Overall the results of immunohistochemistry and immunoblotting were similar and revealed that GluR subunits show distinct responses over the exercise periods and for the different structures analyzed In general, there was increased expression of GluR subunits after longer exercise periods (such as EX30) although some opposite effects were seen after short periods of exercise (Ex3) In a few cases biphasic patterns with decreases and subsequent increases of GluR expression were seen and may represent the outcome of exercise dependent, complex regulatory processes The data show that the protocol used was able to promote plastic GluR changes during exercise, suggesting a specific involvement of these receptors in exercise induced plasticity processes in the brain areas tested (C) 2010 Elsevier B V All rights reserved