A-family anti-inflammatory cyclopentenone prostaglandins: A novel class of non-statin inhibitors of HMG-CoA reductase.

Disruption of the intracellular lipid balance leading to cholesterol accumulation is one of the features of cells that participate in the development of atherosclerotic lesions. Evidence form our laboratory indicates that anti-inflammatory cyclopentenone prostaglandins (cyPGs) of A- and J-family deviate lipid metabolism from the synthesis of cholesterol and cholesteryl esters to the synthesis of phospholipids in foam-cell macrophages. cyPGs possessing an α,ß-unsaturated cyclopentane ring are highly electrophilic substances able to promptly react with reactive cysteines of intracellular molecules through Michael addition. On the other hand, HMG-CoA reductase (HMGCR), the enzyme responsible for the rate-limiting step in cholesterol biosynthesis, presents critically reactive cysteines at the entry of catalytic domain, particularly Cys561, that could be target of cyPG inhibition. In the present study, we showed that cyPGs (but not other non-α,ß-unsaturated PGs) physically interact with HMGCR, in a dithiothreitol- and ß-mercaptoethanol-sensitive way, and block the activity of the catalytic subunit of the enzyme (IC50 for PGA2 = 0.17 µM). PGA2 inhibits HMGCR activity in cultured rat and human macrophages/macrophage-foam cells and leads to enhanced expression of HMGCR protein, as observed with statins. In cell culture models, PGA2 effectively inhibits the reductase at non-toxic doses (e.g., 1 µM) that block cell proliferation thus suggesting that part of the well-known antiproliferative effect of PGA2 may be due to its ability of blocking HMGCR activity, as cells cannot proliferate without a robust cholesterogenesis. Therefore, besides the powerfully anti-inflammatory and antiproliferative effects, the anticholesterogenic effects of PGA2 should be exploited in atherosclerosis therapeutics.

Effects of n-3 fatty acids and exercise on oxidative stress parameters in type 2 diabetic: a randomized clinical trial.

BACKGROUND: The relationship between diabetes and oxidative stress has been previously reported. Exercise represents a useful non-pharmacological strategy for the treatment in type 2 diabetic (T2DM) patients, but high intensity exercise can induce a transient inflammatory state and increase oxidative stress. Nutritional strategies that may contribute to the reduction of oxidative stress induced by acute exercise are necessary. The aim of this study was to examine if n-3 PUFA supplementation intervention can attenuate the inflammatory response and oxidative stress associated with high intensity exercise in this population. As a primary outcome, lipoperoxidation measurements (TBARS and F2-isoprostanes) were selected. METHODS: Thirty T2DM patients, without chronic complications, were randomly allocated into two groups: placebo (gelatin capsules) or n-3 PUFA (capsules containing 180 mg of eicosapentaenoic acid and 120 mg of docosahexaenoic acid). Blood samples were collected fasting before and after 8 weeks supplementation. In the beginning and at the end of protocol, an acute exercise was performed (treadmill), and new blood samples were collected before and immediately after the exercise for measurements of oxidative stress and high-sensitivity C-reactive protein (hs-CRP). RESULTS: After the supplementation period, a decrease in triglycerides levels was observed only in n-3 PUFA supplementation group (mean difference and 95% CI of 0.002 (0.000-0.004), p = 0.005). Supplementation also significantly reduced TRAP levels after exercise (mean difference and 95% CI to 9641 (- 20,068-39,351) for - 33,884 (- 56,976 - -10,793), p = 0.004, Cohen's d effect size = 1.12), but no significant difference was observed in n-3 PUFA supplementation group in lipoperoxidation parameters as TBARS (mean difference and 95% CI to - 3.8 (- 10-2.4) for - 2.9 (- 1.6-7.4) or F2-isoprostanes (mean difference and 95% CI -0.05 (- 0.19-0.10) for - 0.02 (- 0.19-0.16), p > 0.05 for both. CONCLUSION: PUFA n-3 supplementation reduced triglycerides as well as TRAP levels after exercise, without a significant effect on inflammatory and oxidative stress markers.This study is registered at ClinicalTrials.gov with the registration number of NCT03182712.

Preventive Physical Training Partially Preserves Heart Function and Improves Cardiac Antioxidant Responses in Rats After Myocardial Infarction Preventive Physical Training and Myocardial Infarction in Rats.

In acute myocardial infarction (AMI), reactive oxygen species may cause irreversible damage to the heart tissue. Physical training is capable of enhancing antioxidant capacity, acting as a cardioprotective factor. We assessed the preventive effects of physical training on the antioxidant and functional responses of the heart of Wistar Kyoto rats after AMI. Wistar Kyoto rats (n = 12) were allocated to sedentary (SED) or trained (EXE-aerobic training on a treadmill) groups. Echocardiographic exams were performed 48 hr before and 48 hr after the induction of AMI. Superoxide dismutase (SOD) and catalase (CAT) activities, and total glutathione (GSH) were measured in vitro in the heart tissue. After AMI, the EXE group showed higher left ventricular shortening fraction (29%; p = .004), higher cardiac output (37%; p = .032) and reduced myocardial infarction size (16%; p = .007) than SED. The EXE group showed a higher nonenzymatic antioxidant capacity (GSH, 23%; p = .004), but the SOD and CAT activities were higher in SED (23% SOD; p = .021 and 20% CAT; p = .016). In addition, the SOD activity was positively correlated with myocardial infarction size and inversely correlated with cardiac output. Physical training partially preserved cardiac function and increased intracellular antioxidant response in cardiac tissue of animals after AMI.

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

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 ß-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 ß1/ß2 antagonist 10 mg/kg), double blockade (α1 and ß1/ß2), 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 ß-adrenoreceptor blockade did not change this behavior. In resting animals, α1 antagonist, as well as the double (α1/ß) 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 ß-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.

Associação entre remodelamento vascular e núcleo necrótico em artérias coronárias: análise por ultrassom intracoronário com Histologia Virtual® / Association between vascular remodeling and necrotic core in coronary arteries: Virtual Histology intravascular ultrasound analysis

INTRODUÇÃO: Estudos anatomopatológicos sugerem a associação de remodelamento vascular positivo e placas coronárias vulneráveis. O objetivo deste estudo foi avaliar se existe correlação entre o grau de remodelamento vascular positivo e o porcentual de núcleo necrótico em lesões ateroscleróticas coronárias. MÉTODOS: Foram estudados 270 cortes transversais obtidos pela Histologia Virtual® de 30 pacientes, os quais apresentavam remodelamento positivo em segmento de artéria coronária com lesão > 50%, identificada pela angiografia coronária. Foram avaliados 7 cortes transversais por segmento de artéria coronária, incluindo o corte transversal com o maior índice de remodelamento arterial, denominado corte transversal de interesse (corte transversal 4). RESULTADOS: A média de idade foi de 60,8 ± 8,8 anos, 80% eram do sexo masculino e 30% diabéticos. Angina instável foi a apresentação clínica mais frequente (56,6%) e a artéria descendente anterior foi o vaso mais analisado (43%). A área de referência do vaso foi de 15,5 ± 4,9 mm² e o índice de remodelamento no corte transversal 4 foi de 1,2 ± 0,1. Análise de variância de medidas repetidas mostrou maior porcentual de núcleo necrótico no corte transversal de interesse (P < 0,001). Observamos correlação positiva do remodelamento arterial coronário com o núcleo necrótico (r = 0,79; P < 0,001). CONCLUSÕES: O remodelamento positivo da artéria coronária está associado à presença de núcleo necrótico, o qual caracteriza placas ateromatosas vulneráveis. A pesquisa de remodelamento arterial positivo pode ser estratégia útil para a detecção de placas vulneráveis antes de sua ruptura.

BACKGROUND: Anatomopathological studies suggest an association of positive vascular remodeling and vulnerable coronary plaques. The objective of this study was to verify whether there is a correlation between positive vascular remodeling and necrotic core in atherosclerotic coronary lesions. METHODS: We studied 270 cross sections obtained by Virtual Histology® in 30 patients who had positive remodeling in coronary artery segments with lesions > 50%, identified by coronary angiography. Seven cross sections were assessed per segment of coronary artery, including the cross section with the highest remodeling index, denominated cross section of interest (cross section 4). RESULTS: Mean age was 60.8 ± 8.8 years, 80% were male and 30% were diabetic. Unstable angina was the most frequent clinical presentation (56.6%) and the left anterior descending artery was the most analyzed vessel (43%). The vessel reference area was 15.5 ± 4.9 mm² and the remodeling index in cross section 4 was 1.2 ± 0.1. Repeated measures analysis of variance showed a higher percentage of necrotic core in the cross section of interest (P < 0.001). We observed a positive correlation of coronary artery remodeling and necrotic core (r = 0.79; P < 0.001). CONCLUSIONS: Positive coronary artery remodeling is associated to the presence of necrotic core, which characterizes vulnerable atherosclerotic plaques. The search for positive arterial remodeling may be a useful strategy for detecting vulnerable plaques before rupture.

Identificação de genes envolvidos na síntese de proteínas de células musculares lisas com expressão aumentada em placas ateromatosas associados a hiperplasia neointimal após implante de stents não-farmacológicos: estudo GENESIS-R / Identification of genes involved in smooth muscle cell protein synthesis with increased expression in atheromathous plaques associated to neointim al hyperplasia after bare-metal stenting: GENESISI-R Study

Introdução: A reestenose coronária é um fenômeno pouco compreendidoe que permanece como um desafio mesmo na era dos stents farmacológicos. Este estudo tem como objetivo identificar genes envolvidos na síntese de proteínas estruturais e funcionais de células musculares lisas com expressão aumentada em placas ateromatosas de humanos associadosa hiperplasia neointimal após o implante de stents não-farmacológicos. Métodos: Placas ateromatosas foram obtidasmediante aterectomia direcionada, previamente ao implante do stent. A análise da expressão dos genes foi realizada utilizando-se o sistema Affymetrix GeneChip. Os pacientes foramsubmetidos a ultrassom intracoronário 6 meses após o procedimento para análise volumétrica intrastent. Foi avaliada a correlação entre a expressão gênica de placas ateromatosas e o porcentual de hiperplasia intimal intrastent. Resultados: A maioria dos pacientes era do sexo masculino (85,7%), com60,2 ± 11,4 anos de idade, 35,7% eram diabéticos e o porcentual de hiperplasia intimal intrastent foi de 29,9 ± 18,7%.Não houve variação do porcentual de hiperplasia intimal intrastent entre os pacientes com ou sem diabetes (29,5% vs. 30,7%; P = 0,89). Não houve correlação entre a extensão do stent e o porcentual de hiperplasia intimal intrastent (r = -0,26; P = 0,26) ou entre o diâmetro do stent e o porcentual dehiperplasia intimal intrastent (r = 0,14; P = 0,56). Oito genes envolvidos na síntese de proteínas estruturais e funcionais de células musculares lisas apresentaram correlação positiva como porcentual de hiperplasia intimal intrastent. Conclusões: As lesões coronárias de novo apresentam expressão aumentada de genes relacionados com a síntese de proteínas estruturais e funcionais de células musculares lisas associados a futurahiperplasia neointimal intrastent significativa, surgindo como novos alvos terapêuticos.

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.

Acute exercise stimulates macrophage function: possible role of NF-kappaB pathways.

Moderate physical activity when performed on a regular basis presents a number of benefits to the whole organism, especially regarding immune system function, such as augmenting resistance to infections and to cancer growth. Although glutamine production by active muscle cells as well as neuroendocrine alterations mediated by the chronic adaptation to exercise may play a role, the entire mechanism by which exercise makes the immune system aware of challenges remains mostly uncovered. This is particularly true for the effects of an acute exercise session on immune function. In this work, circulating monocytes/macrophages from sedentary rats submitted to an acute (1 h) swimming session were tested for the ability of phagocytosing zymosan particles, phorbol myristate acetate (PMA)-induced hydrogen peroxide production, nitric oxide (NO) release (assessed by nitrate and nitrite production) and the expression of NO synthases (NOS-1, NOS-2 and NOS-3). The results showed that an exercise bout induced a 2.4-fold rise in macrophage phagocytic capacity (p = 0.0041), a 9.6-fold elevation in PMA-induced hydrogen peroxide release into the incubation media (1-h, p = 0.0022) and a 95.5%-augmentation in nitrite basal production (1-h incubation; p = 0.0220), which was associated with a marked expression of NOS-2 (the inducible NOS isoform; p = 0.0319), but not in other NOS gene products. Although NOS-2 expression is nuclear factor-kappaB (NF-kappaB)-dependent, no systemic oxidative stress was found, as inferred from the data of plasma TBARS and glutathione disulphide (GSSG) to glutathione (GSH) ratio in circulating blood erythrocytes which remained constant after the acute exercise. Also, no stressful situation seemed to be faced by monocytes/macrophages, since the expression of the 70-kDa heat shock protein (HSP70) remained unchanged. We conclude that NF-kappaB-dependent induction of NOS-2 and macrophage activation must be related to local factor(s) produced in the surroundings of monocytes/macrophages.

MRP1/GS-X pump ATPase expression: is this the explanation for the cytoprotection of the heart against oxidative stress-induced redox imbalance in comparison to skeletal muscle cells?

Striated muscle activity is always accompanied by oxidative stress (OxStress): the more intense muscle work and/or its duration, the more a redox imbalance may be attained. In spite of cardiac muscle functioning continuously, it is well known that the heart does not suffer from OxStress-induced damage over a broad physiological range. Although the expression of antioxidant enzymes may be of importance in defending heart muscle against OxStress, a series of combined antioxidant therapeutic approaches have proved to be mostly ineffective in avoiding cellular injury. Hence, additional mechanisms may be involved in heart cytoprotection other than antioxidant enzyme activities. The strong cardiotoxic effect of doxorubicin-induced cancer chemotherapy shed light on the possible role for multidrug resistance-associated proteins (MRP) in this context. Muscle activity-induced 'physiological' OxStress enhances the production of glutathione disulfide (GSSG) thus increasing the ratio of GSSG to glutathione (GSH) content inside the cells, which, in turn, leads to redox imbalance. Since MRP1 gene product (a GS-X pump ATPase) is a physiological GSSG transporter, adult Wistar rats were tested for MRP1 expression and activity in the heart and skeletal muscle (gastrocnemius), in as much as the latter is known to be extremely sensitive to muscle activity-induced OxS. MRP1 expression was completely absent in skeletal muscle. In contrast, the heart showed an exercise training-dependent induction of MRP1 protein expression which was further augmented (2.4-fold) as trained rats were challenged with a session of acute exercise. On the other hand, inducible expression of the 70-kDa heat shock protein (HSP70), a universal marker of cellular stress, was completely absent in the heart of sedentary and acutely exercised rats, whereas skeletal muscle showed a conspicuous exercise-dependent HSP70 expression, which decreased by 45% with exercise training. This effect was paralleled by a 58% decrease in GSH content in skeletal muscle which was even higher (an 80%-fall) after training thus leading to a marked redox imbalance ([GSSG]/[GSH] raised up to 38-fold). In the heart, GSH contents and [GSSG]/[GSH] ratio remained virtually unchanged even after exercise challenges, while GS-X pump activity was found to be 20% higher in the heart related to skeletal muscle. These findings suggest that an intrinsic higher capacity to express the MRP1/GS-X pump may dictate the redox status in the heart muscle thus protecting myocardium by preventing GSSG accumulation in cardiomyocytes as compared to skeletal muscle fibres.