Role of alpha- and beta-adrenoreceptors in rat monocyte/macrophage function at rest and acute exercise

Previous studies from our laboratory have demonstrated that a single bout of moderate exercise stimulates macrophage function, increasing phagocytic capacity, and production of hydrogen peroxide and nitric oxide (NO˙) through nuclear factor kappa B activation. In this work, we investigated the role of α- and β-adrenoreceptors on the function of monocyte/macrophages during rest and exercise. Adult male Wistar rats were i.p. administered (100 μL/100 g) with specific adrenergic antagonists before an acute moderate exercise bout: prazosin (α1-specific antagonist 2 mg/kg), propranolol (unspecific β1/β2 antagonist 10 mg/kg), double blockade (α1 and β1/β2), or phosphate-buffered saline (control). Acute exercise consisted in a single swimming session of moderate intensity (5 % body weight overload on the chest) for 60 min. Control groups (rest) received the same antagonists and were killed 60 min after drug administration. Exercise increased phagocytic capacity (1.7-fold, p < 0.05), NO˙ production (5.24 fold, p < 0.001), and inducible nitric oxide synthase (NOS2) expression (by 58.1 %), thus suggesting macrophage activation. The β-adrenoreceptor blockade did not change this behavior. In resting animals, α1 antagonist, as well as the double (α1/β) blockade, however, further increased phagocytic capacity (by up to 261 %, p < 0.001), NO˙ production (by up to 328 %, p < 0.001), and the expressions of NOS2 (by 182 %, p < 0.001) and HSP70 (by 42.5 %, p < 0.01) suggesting a tonic inhibitory effect of α1 stimulation on macrophage activation. In exercised animals, α1-blockade showed similar enhancing effect on phagocytic indices and expressions of NOS and HSP70, particularly in double-blocked groups, although NO˙ production was found to be reduced in exercised animals submitted to both α- and β-blockade. Redox (glutathione) status and lipoperoxidation were evaluated in all test groups and approximately paralleled macrophage NO˙ production. We suggest the prevalence of a peripheral α1-adrenoreceptor inhibitory tonus that limits macrophage responsiveness but operates differently after physical exercise

Prevalência da colonização por Streptococcus agalactiae em uma amostra de mulheres grávidas e não grávidas de Porto Alegre, estado do Rio Grande do Sul / Prevalence of Streptococcus agalactiae colonization in a sample of pregnant and non pregnant women from Porto Alegre, Rio Grande do Sul state, Brazil

Objetivos: Verificar a prevalência de Streptococcus agalactiae em amostras vaginais e retais de mulheres grávidas e não grávidas, analisadas em um laboratório privado de Porto Alegre, Rio Grande do Sul, no período de janeiro de 2011 a junho de 2012.Métodos: Foram incluídos no estudo todos os resultados de culturas de amostras coletadas da vagina e região ano-retal de mulheres grávidas e não grávidas, com idade acima de 18 anos, no período de janeiro de 2011 a junho de 2012, em um laboratório privado do município de Porto Alegre. As amostras foram semeadas em ágar sangue e ágar cromogênico específico para S. agalactiae, sendo realizado o teste de CAMP nas amostras com crescimento bacteriano positivo. A análise estatística foi realizada por meio do teste de qui-quadrado e valores de p menor do que 0,05 foram considerados significativos.Resultados: Foram analisadas 1146 amostras, os quais 963 do ano de 2011 e 183 do primeiro semestre de 2012, sendo que 105 eram de gestantes e 1041 eram de não gestantes. Entre as 1146 mulheres examinadas, 83 (7,2% ? intervalo de confiança 95%: 5,8%-8,8%) estavam colonizadas pelo S. agalactiae. Houve maior frequência de amostras positivas no grupo de gestantes (15,2%) do que no grupo de não gestantes (6,4%) (p igual a 0,002). Esta diferença deveu-se principalmente aos resultados do ano de 2012, quando o grupo de grávidas apresentou 23,1% de amostras positivas, enquanto o grupo de não grávidas teve 6,3% (p igual a 0,004).Conclusões: A incidência elevada de colonização por S. agalactiae entre as gestantes avaliadas enfatiza a importância de detectar essa colonização no final da gravidez, para uma prevenção eficaz da doença estreptocócica neonatal.

Aims: To determine the prevalence of Streptococcus agalactiae in vaginal and rectal samples of pregnant and non-pregnant women, analyzed in a private laboratory in Porto Alegre, Rio Grande do Sul state, Brazil, from January 2011 to June 2012.Methods: The study included all culture results of vaginal and anorectal samples collected from pregnant and non-pregnant women, aged 18 years or more, from January 2011 to June 2012, in a private laboratory in the city of Porto Alegre. The samples were plated on blood agar and chromogenic specific for S. agalactiae, being analyzed in the CAMP test for samples with positive bacterial growth. Statistical analysis was performed using the chi-square and p values less than 0.05 were considered significant.Results: We analyzed 1146 samples, being 963 of 2011 and 183 of the first half of 2012, of which 105 were from pregnant and 1041 and were from non-pregnant women. Among the 1146 women surveyed, 83 (7.2%-95% confidence interval: 5.8%-8.8%) were colonized with S. agalactiae. There was a higher frequency of positive samples in the group of pregnant women (15.2%) than in the group of non-pregnant women (6.4%) (p equals 0.002). This difference was mainly due to the results of the year 2012, when the pregnant group had 23.1% of positive samples, while the non-pregnant group had 6.3% (p equals 0.004).Conclusions: The high incidence of colonization by S. agalactiae among the pregnant women screened emphasizes the importance of detecting this colonization in late pregnancy for the effective prevention of neonatal streptococcal disease.

The effects of periodized concurrent and aerobic training on oxidative stress parameters, endothelial function and immune response in sedentary male individuals of middle age.

The vascular endothelium plays a key role in arterial wall homeostasis by preventing atherosclerotic plaque formation. A primary causal factor of endothelial dysfunction is the reactive oxygen species. Aerobic exercise is ascribed as an important adjuvant therapy in endothelium-dependent cardiovascular disease. However, little is known about the effects of concurrent (aerobic + strength) training on that. For a comparison of the effects of aerobic and concurrent physical training on endothelial function, oxidative stress parameters and the immunoinflammatory activity of monocytes/macrophages, 20 adult male volunteers of middle age were divided into a concurrent training (CT) programme group and an aerobic training group. The glutathione disulphide to glutathione ratio (GSSG/GSH) and plasma lipoperoxide (LPO) levels, as well as flow-mediated dilation (FMD), monocyte/macrophage functional activity (zymosan phagocytosis), body lipid profiles, aerobic capacity (maximal oxygen uptake) and strength parameters (one-repetition maximum test), were measured before and after the exercise training programmes. The CT exhibited reduced acute effects of exercise on the GSSG/GSH ratio, plasma LPO levels and zymosan phagocytosis. The CT also displayed improved lipid profiles, glycaemic control, maximal oxygen uptake and one-repetition maximum test values. In both the aerobic training and the CT, training improved the acute responses to exercise, as inferred from a decrease in the GSSG/GSH ratios. The aerobic sessions did not alter basal levels of plasma LPO or macrophage phagocytic activity but improved FMD values as well as lipid profiles and glycaemic control. In summary, both training programmes improve systemic redox status and antioxidant defences. However, the aerobic training was more efficient in improving FMD in the individuals studied.