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Cortisol é um hormônio esteroide secretado pelo eixo Hipotálamo-Hipófise-Adrenal (HHA), relacionado ao funcionamento adrenal e responde diretamente aos estímulos estressores. O objetivo deste estudo foi quantificar o cortisol em sua forma hidrocortisona utilizando técnica de Espectroscopia de Infravermelho por Transformada de Fourier (ATR-FTIR). O pó da hidrocortisona foi diluído em formol e etanol na proporção de 1:1 e diluídos com água deionizada em seis pontos com range de 1 a 8ng/mL. As leituras foram realizadas com o espectrômetro Agilent Cary 630 para cada curva de diluição. Para análise estatística foram utilizados os pré-processamentos de suavização de Savitsky-Golay 21 pontos e 2ª ordem polinomial, e a correção de linha utilizada de Rubberband e PLSR para realização da curva de calibração. Resultados: A melhor região para análise de concentração da hidrocortisona foi entre 2800-3000cm-¹, responsável pelas ligações químicas entre CH2, CH3 e C-H em cadeias cíclicas. Através do PLSR foram obtidos resultados de predição de RMSE: 0,367 e R2: 0,96%. Os resultados deste estudo sugerem que é possível pela técnica de FTIR-ATR juntamente com a utilização do algoritmo de PLSR, fazer uma curva de calibração para a compreensão dos níveis de hidrocortisona em água.

Introduction: predictive equations to estimate body fat based on simple anthropometric parameters are easy to use in the clinical practice. Objective: to evaluate the relationship between predictive equations based on anthropometric parameters and bioelectrical impedance to estimate body fat in individuals undergoing bariatric surgery. Methods: a prospective and longitudinal study carried out with individuals undergoing bariatric surgery. Body weight, body mass index, waist circumference and body fat percentage estimated by anthropometric parameters and by impedance were evaluated at three moments, one month before, two and six months after surgery. Data were analyzed by one-way ANOVA for repeated measures with Holm-Sidak´s post hoc or Friedman test with Tukey´s post hoc, and Pearson or Spearman correlations, according to data distribution. Significance level adopted 5%. Results: twenty-five subjects composed the final sample. All anthropometric parameters reduced significantly over time (p

Bariatric surgery improves oxidative damage, but little is known about the differences between Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG). This study compared changes in lipid and protein oxidative damage markers and their correlations with body parameters of patients before and after RYGB or SG. Body mass index (BMI), bioimpedance parameters, and biochemical parameters including lipid and protein oxidative damage markers were evaluated before and 6 months after surgery. Data were analyzed by t test or Mann-Whitney rank sum test and Spearman’s correlation coefficient between oxidative damage and other parameters. Twenty-five patients were submitted to RYGB and 14 to SG. There was a significant decrease of BMI, fat mass, fat-free mass, phase angle, serum total protein, transthyretin, and C-reactive protein in both groups (p

Early diagnosis of COVID-19 in suspected patients is essential for contagion control and damage reduction strategies. We investigated the applicability of attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy associated with machine learning in oropharyngeal swab suspension fluid to predict COVID-19 positive samples. The study included samples of 243 patients from two Brazilian States. Samples were transported by using different viral transport mediums (liquid 1 or 2). Clinical COVID-19 diagnosis was performed by the RT-PCR. We built a classification model based on partial least squares (PLS) associated with cosine k-nearest neighbours (KNN). Our analysis led to 84% and 87% sensitivity, 66% and 64% specificity, and 76.9% and 78.4% accuracy for samples of liquids 1 and 2, respectively. Based on this proof-of-concept study, we believe this method could offer a simple, label-free, cost-effective solution for high-throughput screening of suspect patients for COVID-19 in health care centres and emergency departments.

Biomarkers are valuable tools in clinical practice. In 2001, the National Institutes of Health (NIH) standardized the definition of a biomarker as a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacological responses to a therapeutic intervention. A biomarker has clinical relevance when it presents precision, standardization and reproducibility, suitability to the patient, straightforward interpretation by clinicians, and high sensitivity and/or specificity by the parameter it proposes to identify. Thus, serum biomarkers should have advantages related to the simplicity of the procedures and to the fact that venous blood collection is commonplace in clinical practice. We described the potentiality of cfDNA as a general clinical biomarker and focused on endothelial dysfunction. Circulating cell-free DNA (cfDNA) refers to extracellular DNA present in body fluid that may be derived from both normal and diseased cells. An increasing number of studies demonstrate the potential use of cfDNA as a noninvasive biomarker to determine physiologic and pathologic conditions. However, although still scarce, increasing evidence has been reported regarding using cfDNA in cardiovascular diseases. Here, we have reviewed the history of cfDNA, its source, molecular features, and release mechanism. We also show recent studies that have investigated cfDNA as a possible marker of endothelial damage in clinical settings. In the cardiovascular system, the studies are quite new, and although interesting, stronger evidence is still needed. However, some drawbacks in cfDNA methodologies should be overcome before its recommendation as a biomarker in the clinical setting.

One of the health benefits of endurance exercise training (ET) is the stimulation of hematopoiesis. However, the mechanisms underlying ET-induced hematopoietic adaptations are understudied. N–Acetyl–Seryl–Aspartyl–Lysyl–Proline (Ac-SDKP) inhibits proliferation of early hematopoietic progenitor cells. The angiotensin I-converting enzyme (ACE) NH2-terminal promotes hematopoiesis by inhibiting the anti-hematopoietic effect of Ac-SDKP. Here we demonstrate for the first time the role of ACE NH2-terminal in ET-induced hematopoietic adaptations. Wistar rats were subjected to 10 weeks of moderate-(T1) and high-(T2) volume swimming-training. Although both protocols induced classical ET-associated adaptations, only T2 increased plasma ACE NH2-domain activity (by 40%, P=0.0003) and reduced Ac-SDKP levels (by 50%, P

The present study aimed to test the hypothesis that high sodium affects the migratory phenotype of endothelial cells (EC) and investigates mechanisms involved independently of hemodynamic factors. Cell migration was evaluated by Wound-Healing at conditions: High Sodium (HS; 160 mM) and Control (CT; 140 mM). O2− production was evaluated by DHE. NADPH oxidase activity was determined by chemiluminescence assay. Expression of adhesion molecules was analyzed by RT-PCR. Shear Stress was performed using a rhythmic shake. Nitric oxide production was measured by Griess reaction. HS-induced impairment in EC migration while both Candesartan and DPI prevented it. HS increased NADPH oxidase activity, which was blocked by Candesartan. Also, HS increased O2− production that was inhibited by Candesartan. HS decreased adhesion molecules expression via ROS (Integrin Alpha 5, Integrin Beta 1, Integrin Beta 3, VE-Cadherin and PECAM) and via AT1R (PECAM). The nitric oxide production induced by shear stress was decreased after EC exposure to HS while both Candesartan and DPI prevented it. Conclusion: This study demonstrated that HS reduced EC migration by AT1R and ROS derived from NADPH Oxidase and mitochondria. The HS reduction in adhesion molecules expression modulated by ROS and AT1R may help to explain the impairment in migration capacity. Also, HS affected EC functionality by reducing their nitric oxide production in response to shear stress.

The present study aimed to test the hypothesis that increased sodium concentration affects the migratory phenotype of vascular smooth muscle cells (VSMCs) independently of the haemodynamic factors. Cell migration was evaluated by wound-healing assay under the following conditions: high sodium (HS, 160 mM) and control (CT, 140 mM). Cell viability was assessed by annexin V and propidium iodide labeling. Cyclooxygenase-2 (COX-2) gene expression was analysed by reverse transcription polymerase chain reaction. ERK1/2 phosphorylation was assessed by western blot. Exposure of VSMCs to HS reduced migration, and AT1R blockade prevented this response. HS increased COX-2 gene expression, and COX-2 blockade prevented the reduction in VSMC migration induced by HS. HS also increased ERK1/2 phosphorylation, and ERK1/2 inhibition recovered VSMC migration as well as blocked COX-2 gene expression. The TXA2 receptor blocker, but not the prostacyclin receptor blocker, prevented the HS-induced VSMCs migration decrease. HS reduces the migration of VSMCs by increasing COX-2 gene expression via AT1R-ERK1/2 phosphorylation. In addition, increased COX-2 by HS seems to modulate the reduction of VSMCs migration by the TXA2 receptor.

There is an urgent need for ultrarapid testing regimens to detect the severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] infections in real-time within seconds to stop its spread. Current testing approaches for this RNA virus focus primarily on diagnosis by RT-qPCR, which is time-consuming, costly, often inaccurate, and impractical for general population rollout due to the need for laboratory processing. The latency until the test result arrives with the patient has led to further virus spread. Furthermore, latest antigen rapid tests still require 15–30 min processing time and are challenging to handle. Despite increased polymerase chain reaction (PCR)-test and antigen-test efforts, the pandemic continues to evolve worldwide. Herein, we developed a superfast, reagent-free, and nondestructive approach of attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy with subsequent chemometric analysis toward the prescreening of virus-infected samples. Contrived saliva samples spiked with inactivated γ-irradiated COVID-19 virus particles at levels down to 1582 copies/mL generated infrared (IR) spectra with a good signal-to-noise ratio. Predominant virus spectral peaks are tentatively associated with nucleic acid bands, including RNA. At low copy numbers, the presence of a virus particle was found to be capable of modifying the IR spectral signature of saliva, again with discriminating wavenumbers primarily associated with RNA. Discrimination was also achievable following ATR-FTIR spectral analysis of swabs immersed in saliva variously spiked with virus. Next, we nested our test system in a clinical setting wherein participants were recruited to provide demographic details, symptoms, parallel RT-qPCR testing, and the acquisition of pharyngeal swabs for ATR-FTIR spectral analysis. Initial categorization of swab samples into negative versus positive COVID-19 infection was based on symptoms and PCR results (n = 111 negatives and 70 positives). Following training and validation (using n = 61 negatives and 20 positives) of a genetic algorithm-linear discriminant analysis (GA-LDA) algorithm, a blind sensitivity of 95% and specificity of 89% was achieved. This prompt approach generates results within 2 min and is applicable in areas with increased people traffic that require sudden test results such as airports, events, or gate controls.

Fourier Transform-Infrared (FT-IR) absorption spectroscopy has been used to investigate pathophysiological changes caused by sepsis. Sepsis has been defined as a potentially fatal organic dysfunction caused by a dysregulated host response to infection and can lead a patient to risk of death. This study used samples consisting of the blood plasma of mice which were induced to sepsis state, compared to a healthy group using FT-IR associated with attenuated total reflectance (ATR) spectroscopy. For statistical analysis, principal components analysis (PCA) and linear discriminant analysis (LDA) were applied, independently, to the second derivative spectra of both the fingerprint (900−1800 cm−1) and the high wavenumber (2800−3100 cm−1) regions. The technique efficiently differentiated the blood plasma of the two groups, sepsis and healthy mice, the analysis indicating that fatty acids and lipids in the blood samples could be an important biomarker of sepsis.

There is an urgent need for ultra-rapid testing regimens to detect the SARS-CoV-2 [Severe Acute Respiratory Syndrome Coronavirus 2] virus infections in real-time within seconds to stop its spread. Current testing approaches for this RNA virus focus primarily on diagnosis by RT-qPCR, which is time-consuming, costly, often inaccurate and impractical for general population rollout due to the need for laboratory processing. The latency until the test result arrives with the patient has led to further virus spread. Furthermore, latest antigen rapid tests still require 15 to 30 min processing time and are challenging to handle. Despite increased PCR-test and antigen-test efforts the pandemic has entered the worldwide second stage. Herein, we applied a superfast reagent-free and non-destructive approach of attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy with subsequent chemometric analysis to the interrogation of virus-infected samples. Contrived samples with inactivated gamma-irradiated Covid-19 virus particles at levels down to 1582 copies/ml generated infrared (IR) spectra with good signal-to-noise ratio. Predominant virus spectral peaks are associated with nucleic acid bands, including RNA. At low copy numbers, the presence of virus particle was found to be capable of modifying the IR spectral signature of saliva, again with discriminating wavenumbers primarily associated with RNA. Discrimination was also achievable following ATR-FTIR spectral analysis of swabs immersed in saliva variously spiked with virus. Following on, we nested our test system in a clinical setting wherein participants were recruited to provide demographic details, symptoms, parallel RT-qPCR testing and the acquisition of pharyngeal swabs for ATR-FTIR spectral analysis. Initial categorisation of swab samples into negativeversuspositive Covid-19 infection was based on symptoms and PCR results. Following training and validation of a genetic algorithm-linear discriminant analysis (GA-LDA) algorithm, a blind sensitivity of 95% and specificity of 89% was achieved. This prompt approach generates results within two minutes and is applicable in areas with increased people traffic that require sudden test results such as airports, events or gate controls.

To analyze the association between social determinants and morbidities for the outcomes of hospitalization, intensive care unit admission and death by COVID-19 in Espírito Santo State, Brazil.Cross-sectional study with secondary data from confirmed cases of COVID-19, reported in the Notifiable Diseases Information System. Poisson regression was used to estimate the prevalence ratios.104,384 cases reported between February 28th and September 1st, 2020 were studied. The outcomes under study were more frequent among male, elderly, yellow, followed by black, uneducated and with multimorbidity. There was a higher risk of death among people over the age of 60 (PR=56.31 - 95%CI 34.24;92.61), multimorbidities (PR=3.63 - 95%CI 3.16;4.17), kidney disease (PR=3.42 - 95%CI 2.81;4.15) and neoplasms (PR=3.15 - 95%CI 2.41;4.13).The effect of social determinants and morbidities on hospitalization and deaths by COVID-19 is evident.Analisar a associação entre determinantes sociais e morbidades para os desfechos de internação, internação em unidade de terapia intensiva e óbito por COVID-19 no Espírito Santo, Brasil.Estudo transversal, com dados secundários de casos confirmados de COVID-19 notificados no Sistema de Informação de Agravos de Notificação. Utilizou-se regressão de Poisson para estimar as razões de prevalências.Foram estudados 104.384 casos, notificados entre 28 de fevereiro e 1º de setembro de 2020. Os desfechos em estudo foram mais frequentes entre indivíduos do sexo masculino, idosos, de raça/cor da pele amarela ou preta, sem escolaridade, com multimorbidade. Todas as morbidades associaram-se a maior risco de desfechos desfavoráveis. Observou-se maior risco de óbito entre pessoas com idade superior a 60 anos (RP=56,31 - IC95% 34,24;92,61), multimorbidades (RP=3,63 - IC95% 3,16;4,17), doença renal (RP=3,42 - IC95% 2,81;4,15) e neoplasias (RP=3,15 - IC95% 2,41;4,13).Evidencia-se o efeito dos determinantes sociais e morbidades em internação e óbitos por COVID-19.Analizar la asociación entre determinantes sociales y morbilidad para los resultados de hospitalización, ingreso en unidad de cuidados intensivos y muerte por COVID-19 en el Estado de Espírito Santo, Brasil.Estudio transversal con datos secundarios de casos confirmados de COVID-19, reportados en el Sistema de Información de Enfermedades Notificables. Se utilizó la regresión de Poisson para estimar las razones de prevalencia.Se estudiaron 104.384 casos notificados entre el 28 de Febrero y el 1 de Septiembre de 2020. Los desenlaces en estudio fueron más frecuentes entre hombres, ancianos, amarillos, seguidos de negros, no educados y con multimorbilidad. Hubo un mayor riesgo de muerte entre las personas mayores de 60 años (RP=56,31 - IC95% 34,24;92,61), multimorbilidades (RP=3,63 - IC95% 3,16;4,17), enfermedad renal (RP=3,42 - IC95% 2,81;4,15) y neoplasias (RP=3,15 - IC95% 2,41;4,13).El efecto de los determinantes sociales y las morbilidades sobre la hospitalización y las muertes por COVID-19 es evidente.

Muscle damage affects the blood leukocyte profile. Resistance exercise (RE) with blood flow restriction (BFR) attenuates exercise-induced muscle damage (EIMD). Purpose To evaluate muscle damage and the leukocyte profile in response to RE+BFR and to compare with high intensity RE. Methods Twenty volunteers performed the RE in the leg press apparatus in the following groups: RE80, 80% of 1RM (3 × until concentric muscle failure); RE40+BFR, 40% of 1RM with BFR (same total work of RE80 group). The BFR applied was 80% of the total occlusion pressure. Results There were no differences in the blood leukocyte profile among groups despite the lower exercise-induced muscle damage (EIMD) in the RE40+BFR group (RE80: 10.07 ± 2.67 vs. RE40+BFR: 8.25 ± 0.96; cell × 103/mm3). Both groups showed leukocytosis (RE80: 7.59 ± 1.48 vs. 10.07 ± 2.67 and RE40+BFR: 6.57 ± 1.50 vs. 8.25 ± 0.96; cell × 103/mm3) and lymphocytosis (RE80: 2.48 ± 0.83 vs. 3.65 ± 1.31 and RE40+BFR: 2.22 ± 0.23 vs. 3.03 ± 0.65; cell × 103/mm3) immediately after exercise. Leukocytosis (ES 1.12 vs. ES 1.33) and lymphocytosis (ES 1.11 vs. ES 1.76) was greater in the RE40+BFR group. Conclusion RE associated with BFR was accompanied by a greater leukocytosis and lymphocytosis immediately after exercise, with no difference in neutrophils. This leukocyte blood profile may be related to less muscle damage, as well as faster muscle recovery after 24 and 48 h post-exercise.

Despite the important role of iron in cellular homeostasis, iron overload (IO) is associated with systemic and tissue deposits which damage several organs. In order to reduce the impact caused by IO, invasive diagnosis exams (e.g., biopsies) and minimally invasive methods were developed including computed tomography and magnetic resonance imaging. However, current diagnostic methods are still time-consuming and expensive. A cost-effective solution is using Fourier-transform infrared spectroscopy (FTIR) for real-time and molecular-sensitive biofluid analysis during conventional laboratory exams. In this study, we performed the first evaluation of the accuracy of FTIR for IO diagnosis. The study was performed by collecting FTIR spectra of plasma samples of five rats intravenously injected with iron-dextran and five control rats. We developed a classification model based on principal component analysis and supervised methods including J48, random forest, multilayer perceptron, and radial basis function network. We achieved 100% accuracy for the classification of the IO status and provided a list of possible biomolecules related to the vibrational modes detected. In this preliminary study, we give a first step towards real-time diagnosis for acute IO or intoxication. Furthermore, we have expanded the literature knowledge regarding the pathophysiological changes induced by iron overload.

Cardiovascular diseases are the leading cause of mortality and morbidity worldwide. In this study we compared the effects of oral treatment with red pepper ethereal extracts or simvastatin on dyslipidemia, left ventricle remodeling, and atherosclerotic lesions of low-density lipoprotein (LDL) receptor knockout mice (LDLr-/-) fed a hyperlipidic diet. Forty 3-month-old male mice were distributed into four groups: control (C; animals fed a standard diet), HL (ani-mals fed a hyperlipidic diet), and HL+P or HL+S (animals fed a hyperlipidic diet plus red pepper ethereal extracts or simvastatin, respectively). After 60 days, treatment with both red pepper ethereal extracts and simvastatin prevented dyslipidemia, atherosclerotic lesion progression, and left ventricle hypertrophy. Our results suggest a cardioprotective effect of red pepper ethereal extracts in LDLr-/- mice, which is comparable to the well-known effects of simvastatin.

Vein graft failure limits the long-term patency of the saphenous vein used as a conduit for coronary artery bypass graft. Early graft adaptation involves some degree of intima hyperplasia to sustain the hemodynamic stress, but the progress to occlusion in some veins remains unclear. We have demonstrated that stretch-induced up-regulation of cysteine and glycine-rich protein 3 (Crp3) in rat jugular vein and human saphenous vein in response to arterialization. Here, we developed a Crp3-knockout (KO) rat to investigate the role of Crp3 in vascular remodeling. After 28 days of jugular vein arterialization, the intima layer was three-fold thicker in the Crp3-KO that showed comparable smooth muscle cells (SMC) proliferation but an absence of early apoptosis observed in the wild-type (WT) rat. We then investigated the role of Crp3 in early integrin-mediated signaling apoptosis in isolated jugular SMC. Interestingly, under basal conditions, ceramide treatment failed to induce apoptosis in both WT and Crp3-KO SMC. Under stretch, Crp3 expression increased in WT SMC and ceramide-induced apoptosis. Immunoblotting analysis indicated that ceramide stretch-induced apoptosis in SMC is accompanied by a decrease in the phosphorylation status of both focal adhesion kinase (Fak) and protein kinase B (Akt), leading to an increase in Bax expression and caspase-3 cleavage. In contrast, ceramide failed to decrease Fak and Akt phosphorylation in Crp3-KO SMC and, therefore, there was no downstream induction of Bax expression and effector caspase-3 cleavage. Taken together, we provide evidence that stretch-induced Crp3 modulates vein remodeling in response to arterialization by sensitizing SMC to apoptosis.

Early diagnosis of COVID-19 in suspected patients is essential for contagion control and damage reduction strategies. We investigated the applicability of attenuated total reflection (ATR) Fourier transform infrared (FTIR) spectroscopy associated with machine learning in oropharyngeal swab suspension fluid to predict COVID-19 positive samples. The study included samples of 243 patients from two Brazilian States. Samples were transported by using different viral transport mediums (liquid 1 or 2). Clinical COVID-19 diagnosis was performed by the RT-PCR. We built a classification model based on partial least squares (PLS) associated with cosine k-nearest neighbours (KNN). Our analysis led to 84% and 87% sensitivity, 66% and 64% specificity, and 76.9% and 78.4% accuracy for samples of liquids 1 and 2, respectively. Based on this proof-of-concept study, we believe this method could offer a simple, label-free, cost-effective solution for high-throughput screening of suspect patients for COVID-19 in health care centres and emergency departments.

The aim of this study was to evaluate the acute effects of high-intensity eccentric exercise (HI-ECC) combined with blood flow restriction (BFR) on muscle damage markers, and perceptual and cardiovascular responses. Nine healthy men (26 ± 1 years, BMI 24 ± 1 kg m- ²) underwent unilateral elbow extension in two conditions: without (HI-ECC) and with BFR (HI-ECC+BFR). The HI-ECC protocol corresponded to three sets of 10 repetitions with 130% of maximal strength (1RM). The ratings of perceived exertion (RPE) and pain (RPP) were measured after each set. Muscle damage was evaluated by range of motion (ROM), upper arm circumference (CIR) and muscle soreness using a visual analogue scale at different moments (pre-exercise, immediately after, 24 and 48 h postexercise). Systolic (SBP), diastolic (DBP), mean blood pressure (MBP) and heart rate (HR) were measured before exercise and after each set. RPP was higher in HI-ECC+BFR than in HI-ECC after each set. Range of motion decreased postexercise in both conditions; however, in HI-ECC+BFR group, it returned to pre-exercise condition earlier (post-24 h) than HI-ECC (post-48 h). CIR increased only in HI-ECC, while no difference was observed in HI-ECC+BFR condition. Regarding cardiovascular responses, MBP and SBP did not change at any moment. HR showed similar increases in both conditions during exercise while DBP decreased only in HI-ECC condition. Thus, BFR attenuated HI-ECC-induced muscle damage and there was no increase in cardiovascular responses.

Early life experiences have strong influences on brain programming and can affect eating behavior control and body weight later in life. However, there is no consensus about the relationship between neonatal stress and feeding behavior. We evaluated whether maternal deprivation (MD) and maternal separation (MS) alter body weight and appetite using standard rat chow consumption and palatable food. Also, we evaluated anxiety and the expression of the leptin receptor, neuropeptides POMC, CART, NPY in the hypothalamus, as well as the serotoninergic system in the amygdala and hypothalamus as possible modulators of these behaviors. We found a decrease in standard rat chow consumption in MD. However, both neonatal stress protocols increased the consumption of palatable food and led to anxiogenic behavior in male animals. MD led to decreased hypothalamic POMC levels in adult males. Serotonin in the hypothalamus was decreased by both stress models in males and females. In the amygdala, MS decreased serotonin levels while MD increased its metabolite levels. We observed that males are more vulnerable and females are more resilient to the effects of neonatal stress on anxiety-like behavior, as well as on food consumption and on the central changes observed. These data together add support to the concept that the early environment contributes to the development of eating disorders later in life.

Sepsis survivors are at higher risk for cardiovascular events. Lipopolysaccharide (LPS) activates Toll-like receptor 4 (TLR4) in sepsis. Activation of TLR4 modulates vascular smooth muscle cells (VSMCs) phenotype and contributes to cardiovascular changes after sepsis.Investigate changes in VSMCs phenotype caused by LPS-induced TLR4 activation.Rat VSMCs were incubated with LPS. Two incubation conditions were used in cell contraction and migration assays: acute stimulation - LPS stimulus was initiated at the beginning of the assay and maintained throughout; and preconditioning - LPS stimulation was applied prior to the assay then discontinued. Nitric oxide (NO) production, mRNA expression of cytokines and phenotype markers, and interleukin (IL)-6 production were evaluated.LPS increased gene expression of IL-1β, IL-6, TNFα and MCP-1 (p .001), of secretory phenotype markers collagen and vimentin (p .0479) and of the contractile marker smooth muscle 22α (SM22α) (p = .0067). LPS exposure increased IL-6 secretion after 24 and 48 h (p .0001), and NO at 8 and 24 h (p .0249) via inducible nitric oxide synthase (iNOS), as demonstrated by a decrease in NO after incubation with aminoguanidine. Acute stimulation with LPS reduced migration and contraction in a NO-dependent manner, while preconditioning with LPS increased both in an IL-6-dependent manner.LPS affects VSMCs by modulating their secretory, contractile and migratory phenotypes. LPS acute stimulation of VSMCs promoted a NO-dependent reduction in migration and contraction, while preconditioning with LPS promoted IL-6-dependent increases in migration and contraction, evidencing that VSMCs can present phenotype modifications that persist after sepsis, thereby contributing to postsepsis cardiovascular events.

Chronic stimulation of the β-adrenergic sympathetic system induces vascular dysfunction which is associated with increased inflammatory cytokines production. A recently proposed therapy to control vascular injury through inflammatory processes involves inhibition of the enzyme dipeptidyl peptidase-IV (DPP4). The present study investigates whether the inhibition of DPP4 prevents the increase in inflammatory markers induced by isoproterenol and restores endothelial function in vivo and in vitro. Male Wistar rats were divided into four groups: vehicle (VHC), an isoproterenol-treated group (ISO), a sitagliptin-treated group (SITA), and an isoproterenol and sitagliptin-treated group (ISO + SITA). The ISO group exhibited significantly increased contractile responses to phenylephrine associated with reduced endothelial participation, which was totally prevented by DPP4 inhibition. In vitro incubation with isoproterenol had no effect on vascular smooth muscle cells, however isoproterenol increased the activity of DPP4 and the expression of inflammatory cytokines in endothelial cells, while sitagliptin reduced the level of cytokines to basal level. In conclusion, we have shown that beta-adrenergic receptor activation can increase DPP4 activity, which was associated with vascular dysfunction and cytokine expression in endothelial cells. The important role of DPP4 was further supported by sitagliptin, which reversed vascular changes induced by isoproterenol in vivo and in vitro.

Aerobic exercise-induced cardiac hypertrophy (CH) is a physiological response involving accurate orchestration of gene and protein expression of contractile and metabolic components. The microRNAs: miR-208a, miR-208b and miR-499 are each encoded by a myosin gene and thus are also known as ‘MyomiRs’, regulating several mRNA targets that in turn regulate CH and metabolic pathways. To understand the role of myomiRs in the fine-tuning of cardiac myosin heavy chain (MHC) isoform expression by exercise training-induced physiological hypertrophy, Wistar rats were subjected to two different swim training protocols. We observed that high-volume swim training (T2), improved cardiac diastolic function, induced CH and decreased the expression of miR-208a and miR-208b. Consequently, the increased expression of their targets, sex determining region y-related transcription factor 6 (Sox6), Med13, Purβ, specificity proteins (Sp)/Krüppel-like transcription factor 3 (SP3) and HP1β (heterochromatin protein 1β) was more prominent in T2, thus converging to modulate cardiac metabolic and contractile adaptation by exercise training, with an improvement in the α-MHC/β-MHC ratio, bypassing the increase in PPARβ and histone deacetylase (HDAC) class I and II regulation. Altogether, we conclude that high-volume swim training finely assures physiological cardiac remodelling by epigenetic regulation of myomiRs, because inhibition of miR-208a and miR-208b increases the expression of their target proteins and stimulates the interaction among metabolic, contractile and epigenetic genes.

In the last 10 years the number of studies showing the benefits of resistance training (RT) to the cardiovascular system, have grown. In comparison to aerobic training, RT-induced favorable adaptations to the cardiovascular system have been ignored for many years, thus the mechanisms of the RT-induced cardiovascular adaptations are still uncovered. The lack of animal models with comparable protocols to the RT performed by humans hampers the knowledge. We have used squat-exercise model, which is widely used by many others laboratories. However, to a lesser extent, other models are also employed to investigate the cardiovascular adaptations. In the subsequent sections we will review the information regarding cardiac morphological adaptations, signaling pathway of the cardiac cell, cardiac function and the vascular adaptation induced by RT using this animal model developed by Tamaki et al. in 1992. Furthermore, we also describe cardiovascular findings observed using other animal models of RT.

Aims: To determine the effects of resistance training (RT) on the expression of microRNA (miRNA)-214 and its target in sarcoplasmic reticulum Ca2+-ATPase (SERCA2a), and on the morphological and mechanical properties of isolated left ventricular myocytes. Main methods: Male Wistar rats were divided into two groups (n = 7/group): Control (CO) or trained (TR). The exercise-training protocol consisted of: 4 × 12 bouts, 5×/week during 8 weeks, with 80% of one repetition maximum. Key findings: RT increased the left ventricular myocyte width by 15% and volume by 12%, compared with control animals (p &lt, 0.05). The time to half relaxation and time to peak were 8.4% and 4.4% lower, respectively, in cells from TR group as compared to CO group (p &lt, 0.05). RT decreased miRNA-214 level by 18.5% while its target SERCA2a expression were 18.5% higher (p &lt, 0.05). Significance: Our findings showed that RT increases single left ventricular myocyte dimensions and also leads to faster cell contraction and relaxation. These mechanical adaptations may be related to the augmented expression of SERCA2a which, in turn, may be associated with the epigenetic modification of decreased miRNA-214 expression.

Dipeptidyl peptidase IV (DPPIV) is a widely expressed multifunctional serine peptidase that exists as a membrane-anchored cell surface protein or in a soluble form in the plasma and other body fluids. Numerous substrates are cleaved at the penultimate amino acid by DPPIV, including glucagon-like peptide-1 (GLP-1), brain natriuretic peptide (BNP) and stromal cell-derived factor-1 (SDF-α), all of which play important roles in the cardiovascular system. In this regard, recent reports have documented that circulating DPPIV activity correlates with poorer cardiovascular outcomes in human and experimental heart failure (HF). Moreover, emerging evidence indicates that DPPIV inhibitors exert cardioprotective and renoprotective actions in a variety of experimental models of cardiac dysfunction. On the other hand, conflicting results have been found when translating these promising findings from preclinical animal models to clinical therapy. In this review, we discuss how DPPIV might be involved in the cardio-renal axis in HF. In addition, the potential role for DPPIV inhibitors in ameliorating heart disease is revised, focusing on the effects of the main DPPIV substrates on cardiac remodeling and renal handling of salt and water.

Purpose: To evaluate whether cell-free DNA (cfDNA) levels increase immediately after an acute light and heavy resistance exercise (RE) bout and whether cfDNA levels are associated with functional muscle capacity up to 48 h after an exercise session. Methods: Twenty healthy volunteers performed 3 sets of leg-press RE with 80% of 1-repetition maximum (1RM) (RE80) or 40% of 1RM (RE40) with similar exercise volume. Blood lactate was measured after completion of the 3 sets. Creatine kinase, cfDNA, and jump performance were evaluated before (pre) exercise, immediately postexercise (post-0h), and every 24 h until 48 h. Results: Lactate concentration increased similarly in both groups (RE40 4.0 [1.3] mmol/L; RE80 4.8 [1.3] mmol/L). No changes were observed in squat-jump and countermovement-jump performance after RE40; however, both jumps remained reduced until 48 h in the RE80 group. Creatine kinase concentration increased post-24h only in the RE80 group (pre 128.8 [73.7] U/L to post-24h 313.8 [116.4] U/L). cfDNA concentration increased post-0h only in the RE80 group (pre 249.8 [82.3] ng/mL to post-0h 406.3 [67.2] ng/mL). There was a negative correlation between post-0h cfDNA concentration and post-24h squat jump (r = −.521; P = .01) and post-0h cfDNA concentration and post-24h countermovement jump (r = −.539; P = .01). Conclusion: cfDNA increases in response to RE intensity even when not performed until exhaustion. cfDNA measured immediately after RE is a promising biomarker for muscle-performance decrement up to 48 h after a RE bout.

Elevated salt intake induces changes in the extracellular matrix collagen, leading to myocardial stiffness and impaired relaxation. Resistance training (RT) has been used as a remarkably successful strategy in the treatment of heart disease. Therefore, the aim of this study was to investigate the effects of RT on preventing pathological adaptation of the left ventricle (LV) induced by salt overload. Male Wistar rats (10 weeks old) were distributed into four groups (n=8/group): control (CO), control+1% salt (CO+SALT), RT and RT+1% salt (RT+SALT). The RT protocol consisted of 4×12 bouts of squat training, 5/week for 8 weeks, with 80% of one repetition maximum (1RM). Echocardiographs were analyzed and interstitial collagen volume fraction (CVF) was determined in the LV. The 1RM tests in the RT and RT+SALT groups increased 145 and 137%, respectively, compared with the test performed before the training program. LV weight-to-body weight ratio and LV weight-to-tibia length ratio were greater in the RT and RT+SALT groups, respectively, compared with the CO group. Although there was no difference in the systolic function between groups, diastolic function decreased 25% in the CO+SALT group compared with the CO group measured by E/A wave ratio. RT partially prevented this decrease in diastolic function compared with the CO+SALT group. A 1% salt overload increased CVF more than 2.4-fold in the CO+SALT group compared with the CO group and RT prevented this increase. In conclusion, RT prevented interstitial collagen deposition in LV rats subjected to 1% NaCl and attenuated diastolic dysfunction induced by salt overload independent of alterations in blood pressure.

This study evaluated modulators of apoptosis in the myocardium of rats subjected to exercise training. Rats were assigned to non-trained and exercise-trained groups, respectively. The animals ran for 1 h per day, 6 times per week and, for a total of 13 weeks. The left ventricle was processed for analysis of gene and protein anti- (Bcl-2, c-IAP1, c-IAP2, Survivin, ILK, Akt and pAkt) and pro- (Bad) apoptotic expression by real-time PCR (except for Akt and pAkt) and Western blot, respectively. The Bad mRNA (p

Changes in lifestyle such as increase in high-fat food consumption are an important cause for vascular diseases. The present study aimed to investigate the involvement of ACE and TGF-βin the aorta stiffness induced by high-fat diet. C57BL/6 male mice were divided in two groups according to their diet for 8 weeks: standard diet (ST) and high-fat diet (HF). At the end of the protocol, body weight gain, adipose tissue content, serum lipids and glucose levels, and aorta morphometric and biochemical measurements were performed. Analysis of collagen fibers by picrosirius staining of aorta slices showed that HF diet promoted increase of thin (55%) and thick (100%) collagen fibers deposition and concomitant disorganization of these fibers orientations in the aorta vascular wall (50%). To unravel the mechanism involved, myeloperoxidase (MPO) and angiotensin I converting enzyme (ACE) were evaluated by protein expression and enzyme activity. HF diet increased MPO (90%) and ACE (28%) activities, as well as protein expression of ACE. TGF-βwas also increased in aorta tissue of HF diet mice after 8 weeks. Altogether, we have observed that the HF diet-induced aortic stiffening may be associated with increased oxidative stress damage and activation of the RAS in vascular tissue.

Mechanotransduction enables cells to sense and respond to stimuli, such as strain, pressure and shear stress (SS), critical for maintenance of cardiovascular homeostasis or pathological states. The angiotensin II type 1 receptor (AT1R) was the first G protein-coupled receptor described to display stretch-induced activation in cardiomyocytes independent of its ligand Ang II. Here, we assessed whether SS (15dynes/cm2, 10min), an important mechanical force present in the cardiovascular system, activates AT1R independent of its ligand. SS induced extracellular signal-regulated kinase (ERK) activation, used as a surrogate of AT1R activation, in Chinese hamster ovary cells expressing the AT1R (CHO+AT1) but not in wild type cells (CHO). AT1R dependent SS-induced ERK activation involves Ca2+ inflow and activation of Gαq since Ca2+ chelator EGTA or Gαq-specific inhibitor YM-254890 decreased SS-induced ERK activation. On the other hand, the activation of JAK-2 and Src, two intracellular signaling molecules independent of G protein activation, were not differently modulated in the presence of AT1R. Also, ERK activation by SS was observed in CHO cells expressing the mutated AT1R DRY/AAY, which has impaired ability to activate Gαq dependent intracellular signaling. Altogether we provided evidence that SS activates AT1R in the absence of its ligand by both a G protein-dependent and -independent pathways. The biological relevance of these observations deserves to be further investigated since the novel mechanisms described extend the knowledge of the activation of GPCRs independent of its traditional ligand.

The endothelial lining of the vasculature is exposed to a large variety of biochemical and hemodynamic stimuli with different gradients throughout the vascular network. Adequate adaptation requires endothelial cells to be highly plastic, which is reflected by the remarkable heterogeneity of endothelial cells in tissues and organs. Hemodynamic forces such as fluid shear stress and cyclic strain are strong modulators of the endothelial phenotype and function. Although endothelial plasticity is essential during development and adult physiology, proatherogenic stimuli can induce adverse plasticity which contributes to disease. Endothelial-to-mesenchymal transition (EndMT), the hallmark of endothelial plasticity, was long thought to be restricted to embryonic development but has emerged as a pathologic process in a plethora of diseases. In this perspective we argue how shear stress and cyclic strain can modulate EndMT and discuss how this is reflected in atherosclerosis and pulmonary arterial hypertension.

Background OxyElite Pro (OEP) is a dietary supplement to increase metabolism which contains as key stimulant the ingredient 1,3-dimethylamylamine (DMAA). Serious adverse effects have been reported after OEP consumption however, these effects are related to poisoning or overdose. To our knowledge, no one studied the effects of OEP at controlled doses. Thus, the aim of this study was to evaluate acute and chronic OEP affects, at controlled doses in Wistar rats, on physical performance, metabolic parameters, liver injury markers and oxidative stress markers and mitochondrial biogenesis in skeletal muscle. Methods Rats were divided in control, 4.3 mg OEP/kg, 12.9 mg OEP/kg and 25.8 mg OEP/kg. All groups were submitted to supplementation with OEP for 4 weeks and the experimental protocols were performed 30 min after the first OEP administration (acute response) and 30 min after the last OEP administration at the end of the forth week (chronic response). Results Running distance and running time increased after acute administration of 12.9 mg OEP/kg (2.6-fold) and 25.8 mg OEP/kg (2.8-fold). Since no effect on the exercise tolerance test was observed at the lower OEP dose (4.3 mg OEP/kg), this group was removed from further analyzes. On other hand, running distance and running time decreased after daily supplementation for 4 weeks also in both groups (64% in 12.9 mg OEP/kg and 72% in 25.8 mg OEP/kg). Chronic supplementation at both 12.9 and 25.8 mg OEP/kg decreased TBARS levels in soleus muscle (36 and 31%) and liver (43 and 25%). AOPP was also decreased by both doses in the liver (39 and 45%). Chronic administration of the highest dose, 25.8 mg OEP/kg, was able to reduce mRNA expression of PGC-1α in soleus muscle (25%). No effect was found in other analyses such as spontaneous physical activity, body weight, food and water intake, hepatic toxicity, cardiac oxidative stress and mitochondrial DNA amount. Conclusion Maximum and not recommended doses of OEP ingested acutely presented stimulating effect on the ability to exercise. However, its daily consumption for 4 weeks showed antioxidant effects in soleus muscle and liver which may have decreased the PGC-1α mRNA expression on soleus muscle and contributed to the impaired performance in the exercise tolerance test. Fundo OxyElite Pro (OEP) é um suplemento alimentar para aumentar o metabolismo que contém como estimulante chave o ingrediente 1,3-dimetilamilamina (DMAA). Efeitos adversos graves foram relatados após o consumo de OEP, no entanto, esses efeitos estão relacionados a envenenamento ou overdose. Até onde sabemos, ninguém estudou os efeitos da OEP em doses controladas. Assim, o objetivo deste estudo foi avaliar os efeitos agudos e crônicos da OEP, em doses controladas em ratos Wistar, no desempenho físico, parâmetros metabólicos, marcadores de lesão hepática e marcadores de estresse oxidativo e biogênese mitocondrial no músculo esquelético. Métodos Os ratos foram divididos em controle, 4,3 mg OEP/kg, 12,9 mg OEP/kg e 25,8 mg OEP/kg. Todos os grupos foram submetidos à suplementação com OEP por 4 semanas e os protocolos experimentais foram realizados 30 minutos após a primeira administração de OEP (resposta aguda) e 30 minutos após a última administração de OEP ao final da quarta semana (resposta crônica). Resultados A distância e o tempo de corrida aumentaram após a administração aguda de 12,9 mg OEP/kg (2,6 vezes) e 25,8 mg OEP/kg (2,8 vezes). Como nenhum efeito no teste de tolerância ao exercício foi observado na dose mais baixa de OEP (4,3 mg OEP/kg), esse grupo foi removido de análises posteriores. Por outro lado, a distância percorrida e o tempo de corrida diminuíram após a suplementação diária por 4 semanas também em ambos os grupos (64% em 12,9 mg OEP/kg e 72% em 25,8 mg OEP/kg). A suplementação crônica de 12,9 e 25,8 mg OEP/kg diminuiu os níveis de TBARS no músculo sóleo (36 e 31%) e no fígado (43 e 25%). AOPP também foi diminuída por ambas as doses no fígado (39 e 45%). A administração crônica da maior dose, 25,8 mg OEP/kg, foi capaz de reduzir a expressão de mRNA de PGC-1α no músculo sóleo (25%). Nenhum efeito foi encontrado em outras análises, como atividade física espontânea, peso corporal, ingestão de alimentos e água, toxicidade hepática, estresse oxidativo cardíaco e quantidade de DNA mitocondrial. Conclusão Doses máximas e não recomendadas de OEP ingeridas de forma aguda apresentaram efeito estimulante sobre a capacidade de exercício. No entanto, seu consumo diário por 4 semanas mostrou efeitos antioxidantes no músculo sóleo e fígado, o que pode ter diminuído a expressão do mRNA de PGC-1α no músculo sóleo e contribuído para o desempenho prejudicado no teste de tolerância ao exercício.

Aim: To investigate the effects of swimming training on the renin-angiotensin system (RAS) during the development of hypertensive disease.Main methods: Male spontaneously hypertensive rats (SHR) were randomized into: sedentary young (SY), trained young (TV), sedentary adult (SA), and trained adult (TA) groups. Swimming was performed 5 times/wk/8wks.Key findings: Trained young and adult rats showed both decreased systolic and mean blood pressure, and bradycardia after the training protocol. the left ventricular hypertrophy (LVH) was observed only in the TA group (12.7%), but there was no increase on the collagen volume fraction. Regarding the components of the RAS, TV showed lower activity and gene expression of angiotensinogen (AGT) compared to SY. the TA group showed lower activity of circulatory RAS components, such as decreased serum ACE activity and plasma renin activity compared to SA. However, depending on the age, although there were marked differences in the modulation of the RAS by training, both trained groups showed a reduction in circulating angiotensin II levels which may explain the lower blood pressure in both groups after swimming training.Significance: Swimming training regulates the RAS differently in adult and young SHR rats. Decreased local cardiac RAS may have prevented the LVH exercise-induced in the TV group. Both groups decreased serum angiotensin II content, which may, at least in part, contribute to the lowering blood pressure effect of exercise training. (C) 2011 Elsevier Inc. All rights reserved. Univ São Paulo, Sch Phys Educ & Sport, Biochem Lab, BR-05508900 São Paulo, Brazil Univ São Paulo Med Sch, Heart Inst InCor, Hypertens Unit, São Paulo, SP, Brazil Universidade Federal de São Paulo, Dept Med, Div Nephrol, São Paulo, SP, Brazil Univ São Paulo, Inst Biomed Sci, Dept Pharmacol, BR-05508900 São Paulo, Brazil Universidade Federal de São Paulo, Dept Med, Div Nephrol, São Paulo, SP, Brazil Web of Science

Myocardial hypertrophy and dysfunction occur in response to excessive catecholaminergic drive. Adverse cardiac remodelling is associated with activation of proinflammatory cytokines in the myocardium. To test the hypothesis that exercise training can prevent myocardial dysfunction and production of proinflammatory cytokines induced by β-adrenergic hyperactivity, male Wistar rats were assigned to one of the following four groups: sedentary non-treated (Con); sedentary isoprenaline treated (Iso); exercised non-treated (Ex); and exercised plus isoprenaline (Iso+Ex). Echocardiography, haemodynamic measurements and isolated papillary muscle were used for functional evaluations. Real-time RT-PCR and Western blot were used to quantify tumour necrosis factor α, interleukin-6, interleukin-10 and transforming growth factor β1 (TGF-β1) in the tissue. NF-κB expression in the nucleus was evaluated by immunohistochemical staining. The Iso rats showed a concentric hypertrophy of the left ventricle (LV). These animals exhibited marked increases in LV end-diastolic pressure and impaired myocardial performance in vitro, with a reduction in the developed tension and maximal rate of tension increase and decrease, as well as worsened recruitment of the Frank–Starling mechanism. Both gene and protein levels of tumour necrosis factor α and interleukin-6, as well as TGF-β1 mRNA, were increased. In addition, the NF-κB expression in the Iso group was significantly raised. In the Iso+Ex group, the exercise training had the following effects: (1) it prevented LV hypertrophy; (ii) it improved myocardial contractility; (3) it avoided the increase of proinflammatory cytokines and improved interleukin-10 levels; and (4) it attenuated the increase of TGF-β1 mRNA. Thus, exercise training in a model of β-adrenergic hyperactivity can avoid the adverse remodelling of the LV and inhibit inflammatory cytokines. Moreover, the cardioprotection is related to beneficial effects on myocardial performance.

It has been demonstrated that human adipose tissue-derived mesenchymal stem cells (hASCs) enhance vascular density in ischemic tissues, suggesting that they can differentiate into vascular cells or release angiogenic factors that may stimulate neoangiogenesis. Moreover, there is evidence that shear stress (SS) may activate proliferation and differentiation of embryonic and endothelial precursor stem cells into endothelial cells (ECs). In this work, we investigated the effect of laminar SS in promoting differentiation of hASCs into ECs. SS (10 dyn/cm(2) up to 96 h), produced by a cone plate system, failed to induce EC markers (CD31, vWF, Flk-1) on hASC assayed by RT-PCR and flow cytometry. In contrast, there was a cumulative production of nitric oxide (determined by Griess Reaction) and vascular endothelial growth factor (VEGF; by ELISA) up to 96 h of SS stimulation ( in nmol/10(4) cells: static: 0.20 +/- 0.03; SS: 1.78 +/- 0.38, n = 6; VEGF in pg/10(4) cells: static: 191.31 +/- v35.29; SS: 372.80 +/- 46.74, n = 6, P < 0.05). Interestingly, the VEGF production was abrogated by 5 mM N(G)-L-nitro-arginine methyl ester (L-NAME) treatment (VEGF in pg/10(4) cells: SS: 378.80 +/- 46.74, n = 6; SS + L-NAME: 205.84 +/- 91.66, n = 4, P < 0.05). The results indicate that even though SS failed to induce EC surface markers in hASC under the tested conditions, it stimulated NO-dependent VEGF production.

To evaluate the effects of heat acclimation on sweat rate redistribution and thermodynamic parameters, 9 tropical native volunteers were submitted to 11 days of exercise-heat exposures (40+/-0 degrees C and 45.1+/-0.2% relative humidity). Sudomotor function was evaluated by measuring total and local (forehead, chest, arm, forearm, and thigh) sweat rates, local sweat sodium concentration, and mean skin and rectal temperatures. We also calculated heat production (H), heat storage (S), heat exchange by radiation (R) and by convection (C), evaporated sweat (E(sw)), sweating efficiency (eta(sw)), skin wettedness (w(sk)), and the ratio between the heat storage and the sum of heat production and heat gains by radiation and convection (S/(H+R+C)). The heat acclimation increased the whole-body sweat rate and reduced the mean skin temperature. There were changes in the local sweat rate patterns: on the arm, forearm, and thigh it increased significantly from day 1 to day 11 (all p

Aims Cysteine- and glycine-rich protein 3/muscle LIM-domain protein (CRP3/MLP) mediates protein–protein interaction with actin filaments in the heart and is involved in muscle differentiation and vascular remodelling. Here, we assessed the induction of CRP3/MLP expression during arterialization in human and rat veins. Methods and results Vascular CRP3/MLP expression was mainly observed in arterial samples from both human and rat. Using quantitative real time RT–PCR, we demonstrated that the CRP3/MLP expression was 10 times higher in smooth muscle cells (SMCs) from human mammary artery (h-MA) vs. saphenous vein (h-SV). In endothelial cells (ECs), CRP3/MLP was scarcely detected in either h-MA or h-SV. Using an ex vivo flow through system that mimics arterial condition, we observed induction of CRP3/MLP expression in arterialized h-SV. Interestingly, the upregulation of CRP3/MLP was primarily dependent on stretch stimulus in SMCs, rather than shear stress in ECs. Finally, using a rat vein in vivo arterialization model, early (1–14 days) CRP3/MLP immunostaining was observed predominantly in the inner layer and later (28–90 days) it appeared more scattered in the vessel layers. Conclusion Here we provide evidence that CRP3/MLP is primarily expressed in arterial SMCs and that stretch is the main stimulus for CRP3/MLP induction in veins exposed to arterial haemodynamic conditions.

Introduction.This study addressed the role of the local renin-angiotensin system (RAS) in the left ventricular hypertrophy (LVH) induced by swimming training using pharmacological blockade. Materials and methods. Female Wistar rats treated with enalapril maleate (60 mg.kg-1.d -1, n=38), losartan (20 mg.kg-1.d-1, n=36) or high salt diet (1% NaCl, n=38) were trained by two protocols (T1: 60-min swimming session, 5 days per week for 10 weeks and T2: the same T1 protocol until the 8th week, then 9th week they trained twice a day and 10th week they trained three times a day). Salt loading prevented activation of the systemic RAS. Haemodynamic parameters, soleus citrate synthase (SCS) activity and LVH (left ventricular/body weight ratio, mg/g) were evaluated. Results. Resting heart rate decreased in all trained groups. SCS activity increased 41% and 106% in T1 andT2 groups, respectively. LVH was 20% and 30% in T1 andT2 groups, respectively. Enalapril prevented 39% of the LVH in T2 group (p Conclusions.These data provide evidence that the physiological LVH induced by swimming training is regulated by local RAS independent from the systemic, because the hypertrophic response was maintained even when PRA was inhibited by chronic salt loading. However, other systems can contribute to this process.

Resistance training is accompanied by cardiac hypertrophy, but the role of the renin-angiotensin system (RAS) in this response is elusive. We evaluated this question in 36 male Wistar rats divided into six groups: control ( n = 6); trained ( n = 6); control + losartan (10 mg·kg−1·day−1, n = 6); trained + losartan ( n = 6); control + high-salt diet (1%, n = 6); and trained + high-salt diet (1%, n = 6). High salt was used to inhibit the systemic RAS and losartan to block the AT1 receptor. The exercise protocol consisted of: 4 × 12 bouts, 5×/wk during 8 wk, with 65–75% of one repetition maximum. Left ventricle weight-to-body weight ratio increased only in trained and trained + high-salt diet groups (8.5% and 10.6%, P < 0.05) compared with control. Also, none of the pathological cardiac hypertrophy markers, atrial natriuretic peptide, and αMHC (α-myosin heavy chain)-to-βMHC ratio, were changed. ACE activity was analyzed by fluorometric assay (systemic and cardiac) and plasma renin activity (PRA) by RIA and remained unchanged upon resistance training, whereas PRA decreased significantly with the high-salt diet. Interestingly, using Western blot analysis and RT-PRC, no changes were observed in cardiac AT2 receptor levels, whereas the AT1 receptor gene (56%, P < 0.05) and protein (31%, P < 0.05) expressions were upregulated in the trained group. Also, cardiac ANG II concentration evaluated by ELISA remained unchanged (23.27 ± 2.4 vs. 22.01 ± 0.8 pg/mg, P > 0.05). Administration of a subhypotensive dose of losartan prevented left ventricle hypertrophy in response to the resistance training. Altogether, we provide evidence that resistance training-induced cardiac hypertrophy is accompanied by induction of AT1 receptor expression with no changes in cardiac ANG II, which suggests a local activation of the RAS consistent with the hypertrophic response.