Modulation of collagen synthesis and its gene expression in human skin fibroblasts by tocotrienol-rich fraction

Introduction

Skin aging may occur as a result of increased free radicals in the body. Vitamin E, the major chain-breaking antioxidant, prevents propagation of oxidative stress, especially in biological membranes. In this study, the molecular mechanism of tocotrienol-rich fraction (TRF) in preventing oxidative stress-induced skin aging was evaluated by determining the rate of total collagen synthesis and its gene expression in human skin fibroblasts.

Material and methods

Primary culture of human skin fibroblasts was derived from circumcision foreskin of 9 to 12 year-old boys. Fibroblast cells were divided into 5 different treatment groups: untreated control, hydrogen peroxide (H₂O₂)-induced oxidative stress (20 µM H₂O₂ exposure for 2 weeks), TRF treatment, and pre- and post-treatment of TRF to H₂O₂-induced oxidative stress.

Results

Our results showed that H₂O₂-induced oxidative stress decreased the rate of total collagen synthesis and down-regulated COL I and COL III in skin fibroblasts. Pre-treatment of TRF protected against H₂O₂-induced oxidative stress as shown by increase in total collagen synthesis and up-regulation of COL I and COL III (p<0.05) genes. However, similar protective effects against H₂O₂-induced oxidative stress were not observed in the post-treated fibroblasts.

Conclusions

Tocotrienol-rich fraction protects against H₂O₂-induced oxidative stress in human skin fibroblast culture by modulating the expression of COL I and COL III genes with concomitant increase in the rate of total collagen synthesis. These findings may indicate TRF protection against oxidative stress-induced skin aging.     

Noninvasive measurement of cardiac performance in recovery from exercise in heart failure patients

OBJECTIVE:

To examine the association between cardiac performance during recovery and the severity of heart failure, as determined by clinical and cardiopulmonary exercise test responses.

METHODS:

As part of a retrospective cohort study, 46 heart failure patients and 13 normal subjects underwent cardiopulmonary exercise testing while cardiac output was measured using a noninvasive device. Cardiac output in recovery was expressed as the slope of a single exponential relationship between cardiac output and time; the recovery-time constant was assessed in relation to indices of cardiac function, along with clinical, functional, and cardiopulmonary exercise responses.

RESULTS:

The recovery time constant was delayed in patients with heart failure compared with normal subjects (296.7±238 vs. 110.1±27 seconds, p <0.01), and the slope of the decline of cardiac output in recovery was steeper in normal subjects compared with heart failure patients (p<0.001). The slope of the decline in cardiac output recovery was inversely related to peak VO₂ (r = -0.72, p<0.001) and directly related to the VE/VCO₂ slope (r = 0.57, p<0.001). Heart failure patients with abnormal recovery time constants had lower peak VO₂, lower VO₂ at the ventilatory threshold, lower peak cardiac output, and a heightened VE/VCO₂ slope during exercise.

CONCLUSIONS:

Impaired cardiac output recovery kinetics can identify heart failure patients with more severe disease, lower exercise capacity, and inefficient ventilation. Estimating cardiac output in recovery from exercise may provide added insight into the cardiovascular status of patients with heart failure.     

Effects of arterial oxygen tension and cardiac output on venous saturation: a mathematical modeling approach

OBJECTIVES:

Hemodynamic support is aimed at providing adequate O₂ delivery to the tissues; most interventions target O₂ delivery increase. Mixed venous O₂ saturation is a frequently used parameter to evaluate the adequacy of O₂ delivery.

METHODS:

We describe a mathematical model to compare the effects of increasing O₂ delivery on venous oxygen saturation through increases in the inspired O₂ fraction versus increases in cardiac output. The model was created based on the lungs, which were divided into shunted and non-shunted areas, and on seven peripheral compartments, each with normal values of perfusion, optimal oxygen consumption, and critical O₂ extraction rate. O₂ delivery was increased by changing the inspired fraction of oxygen from 0.21 to 1.0 in steps of 0.1 under conditions of low (2.0 L.min^-1) or normal (6.5 L.min^-1) cardiac output. The same O₂ delivery values were also obtained by maintaining a fixed O₂ inspired fraction value of 0.21 while changing cardiac output.

RESULTS:

Venous oxygen saturation was higher when produced through increases in inspired O₂ fraction versus increases in cardiac output, even at the same O₂ delivery and consumption values. Specifically, at high inspired O₂ fractions, the measured O₂ saturation values failed to detect conditions of low oxygen supply.

CONCLUSIONS:

The mode of O₂ delivery optimization, specifically increases in the fraction of inspired oxygen versus increases in cardiac output, can compromise the capability of the “venous O₂ saturation” parameter to measure the adequacy of oxygen supply. Consequently, venous saturation at high inspired O₂ fractions should be interpreted with caution.     

Acute effect of phosphodiesterase type 5 inhibitor on serum oxidative status and prolidase activities in men with erectile dysfunction

OBJECTIVES:

To investigate the acute effect of phosphodiesterase type 5 (PDE5) inhibitor on erectile dysfunction by evaluating serum oxidative status and prolidase activity.

METHODS:

Serum samples of 36 patients with erectile dysfunction and 30 control cases were analyzed for total antioxidant status, total oxidant status, and prolidase activity, before and after the administration of tadalafil citrate.

RESULTS:

Before and after tadalafil citrate administration, serum total antioxidant status, total oxidant status, and prolidase were 1.1±0.0 vs. 1.6±0.0 µmol H₂O₂ Eq/L, 10.3±1.1 vs. 6.9±1.2 µmol H₂O₂ Eq/L, and 236.4±19.5 vs. 228.2±19.2 U/L, respectively (p<0.0001 for all).

CONCLUSIONS:

Evaluation of serum oxidative status and prolidase activity confirmed the beneficial acute effects of PDE5 inhibitor in patients with erectile dysfunction.     

Hepatoprotective Effect of Cymbopogon Citratus Aqueous Extract Against Hydrogen Peroxide-Induced Liver Injury in Male Rats

Background

Cymbopogon citratus (Poaceae) a tropical perennial herb plant that is widely cultivated to be eaten either fresh with food or dried in tea or soft drink has been reported to possess a number of medicinal and aromatic properties. This study aimed at evaluating the protective effects of C. citratus aqueous extract against liver injury induced by hydrogen peroxide (H₂O₂), in male rats.

Materials and Methods

Twenty-five rats were randomly divided into five different groups of five animals in each group; (1) Control. (2) Received H₂O₂ (0.5%) with drinking water. (3), and (4) received H₂O₂ and C. citratus (100 mg·kg⁻¹ b wt), vitamin C (250 mg·kg⁻¹ b wt) respectively. (5), was given C. citratus alone. The treatments were administered for 30 days. Blood samples were collected and serum was used for biochemical assay including liver enzymes activities, total protein, total bilirubin and malonaldehyde, glutathione in serum and liver homogenates. Liver was excised and routinely processed for histological examinations.

Results

C. citratus attenuated liver damage due to H₂O₂ administration as indicated by the significant reduction (p<0.05), in the elevated levels of ALT, AST, ALP, LDH, TB, and MDA in serum and liver homogenates; increase in TP and GSH levels in serum and liver homogenates; and improvement of liver histo-pathological changes. These effects of the extract were similar to that of vitamin C which used as antioxidant reference.

Conclusion

C. citratus could effectively ameliorate H₂O₂-induced oxidative stress and prevent liver injury in male rats.     

A sigmoidal fit for pressure-volume curves of idiopathic pulmonary fibrosis patients on mechanical ventilation: clinical implications

OBJECTIVE:

Respiratory pressure-volume curves fitted to exponential equations have been used to assess disease severity and prognosis in spontaneously breathing patients with idiopathic pulmonary fibrosis. Sigmoidal equations have been used to fit pressure-volume curves for mechanically ventilated patients but not for idiopathic pulmonary fibrosis patients. We compared a sigmoidal model and an exponential model to fit pressure-volume curves from mechanically ventilated patients with idiopathic pulmonary fibrosis.

METHODS:

Six idiopathic pulmonary fibrosis patients and five controls underwent inflation pressure-volume curves using the constant-flow technique during general anesthesia prior to open lung biopsy or thymectomy. We identified the lower and upper inflection points and fit the curves with an exponential equation, V = A-B.e^-k.P, and a sigmoid equation, V = a+b/(1+e^-(P-c)/d).

RESULTS:

The mean lower inflection point for idiopathic pulmonary fibrosis patients was significantly higher (10.5±5.7 cm H₂O) than that of controls (3.6±2.4 cm H₂O). The sigmoidal equation fit the pressure-volume curves of the fibrotic and control patients well, but the exponential equation fit the data well only when points below 50% of the inspiratory capacity were excluded.

CONCLUSION:

The elevated lower inflection point and the sigmoidal shape of the pressure-volume curves suggest that respiratory system compliance is decreased close to end-expiratory lung volume in idiopathic pulmonary fibrosis patients under general anesthesia and mechanical ventilation. The sigmoidal fit was superior to the exponential fit for inflation pressure-volume curves of anesthetized patients with idiopathic pulmonary fibrosis and could be useful for guiding mechanical ventilation during general anesthesia in this condition.     

Anti-Oxidant Effects of Pomegranate Juice on Saccharomyces Cerevisiae Cell Growth

Background

Pomegranate juice has a number of positive effects on both human and animal subjects.

Material and methods

Four groups were used in this study. i: Control group, ii: H₂O₂ group, iii: Pomegranate juice (PJ) group and iv: PJ + H₂O₂ group. Following the sterilization method for pomegranate juice (10%) and H₂O₂ (6% v/v), Saccharomyces cerevisiae cultures were added and the cultivation incubated at 35°C for 72 hours. Fatty acids and vitamin concentrations were measured using HPLC and GC and the total protein bands profile were determined by SDS-PAGE.

Results

According to our results statistically significant differences have been determined among the study groups in terms of fatty acids and vitamin (p<0,05). Fatty acid synthesis, vitamin control and cell density increased in groups to which PJ was given in comparison with the control group (p<0,05). Pomegranate juice increased vitamins, fatty acids and total protein expression in Saccharomyces cerevisiae in comparison with the control.

Conclusion

Pomegranate juice has a positive effect on fatty acid, vitamin and protein synthesis by Saccharomyces cerevisiae. Accordingly, we believe that it has significantly decreased oxidative damage thereby making a positive impact on yeast development.     

Effects of Exercise Training in Patients with Chronic Heart Failure and Sleep Apnea

Study Objectives:

To test the effects of exercise training on sleep and neurovascular control in patients with systolic heart failure with and without sleep disordered breathing.

Design:

Prospective interventional study.

Setting:

Cardiac rehabilitation and exercise physiology unit and sleep laboratory.

Patients:

Twenty-five patients with heart failure, aged 42 to 70 years, and New York Heart Association Functional Class I-III were divided into 1 of 3 groups: obstructive sleep apnea (n = 8), central sleep apnea (n = 9) and no sleep apnea (n = 7).

Interventions:

Four months of no-training (control) followed by 4 months of an exercise training program (three 60-minute, supervised, exercise sessions per week).

Measures and Results:

Sleep (polysomnography), microneurography, forearm blood flow (plethysmography), peak VO_2, and quality of life were evaluated at baseline and at the end of the control and trained periods. No significant changes occurred in the control period. Exercise training reduced muscle sympathetic nerve activity (P < 0.001) and increased forearm blood flow (P < 0.01), peak VO₂(P < 0.01), and quality of life (P < 0.01) in all groups, independent of the presence of sleep apnea. Exercise training improved the apnea-hypopnea index, minimum O₂ saturation, and amount stage 3-4 sleep (P < 0.05) in patients with obstructive sleep apnea but had no significant effects in patients with central sleep apnea.

Conclusions.

The beneficial effects of exercise training on neurovascular function, functional capacity, and quality of life in patients with systolic dysfunction and heart failure occurs independently of sleep disordered breathing. Exercise training lessens the severity of obstructive sleep apnea but does not affect central sleep apnea in patients with heart failure and sleep disordered breathing.

Citation:

Ueno LM; Drager LF; Rodrigues ACT; Rondon MUPB; Braga AMFW; Mathias W; Krieger EM; Barretto ACP; Middlekauff HR; Lorenzi-Filho G; Negrão CE. Effects of exercise training in patients with chronic heart failure and sleep apnea. SLEEP 2009;32(5):637-647.     

Short-term add-on therapy with angiotensin receptor blocker for end-stage inotrope-dependent heart failure patients: B-type natriuretic peptide reduction in a randomized clinical trial

OBJECTIVE:

We aimed to evaluate angiotensin receptor blocker add-on therapy in patients with low cardiac output during decompensated heart failure.

METHODS:

We selected patients with decompensated heart failure, low cardiac output, dobutamine dependence, and an ejection fraction <0.45 who were receiving an angiotensin-converting enzyme inhibitor. The patients were randomized to losartan or placebo and underwent invasive hemodynamic and B-type natriuretic peptide measurements at baseline and on the seventh day after intervention. ClinicalTrials.gov: {"type":"clinical-trial","attrs":{"text":"NCT01857999","term_id":"NCT01857999"}}NCT01857999.

RESULTS:

We studied 10 patients in the losartan group and 11 patients in the placebo group. The patient characteristics were as follows: age 52.7 years, ejection fraction 21.3%, dobutamine infusion 8.5 mcg/kg.min, indexed systemic vascular resistance 1918.0 dynes.sec/cm⁵.m², cardiac index 2.8 L/min.m², and B-type natriuretic peptide 1,403 pg/mL. After 7 days of intervention, there was a 37.4% reduction in the B-type natriuretic peptide levels in the losartan group compared with an 11.9% increase in the placebo group (mean difference, -49.1%; 95% confidence interval: -88.1 to -9.8%, p = 0.018). No significant difference was observed in the hemodynamic measurements.

CONCLUSION:

Short-term add-on therapy with losartan reduced B-type natriuretic peptide levels in patients hospitalized for decompensated severe heart failure and low cardiac output with inotrope dependence.     

Comparison of the effects of propofol and midazolam on inflammation and oxidase stress in children with congenital heart disease undergoing cardiac surgery

Purpose

To investigate and compare the effects of propofol and midazolam on inflammation and oxidase stress in children with congenital heart disease undergoing cardiac surgery.

Materials and Methods

Thirty-two ASA class I-II children with congenital heart disease undergoing cardiac surgery were randomly divided into two groups: propofol combined with low dose fentanyl (PF group, n = 16) and midazolam combined with low dose fentanyl (MF group, n = 16). Tracheal extubation time and length of Intensive Care Unit (ICU) stay were recorded. Blood samples were taken before operation (T₀), at 2 h after release of the aorta cross-clamp (T₃) and at 24 h after operation (T₄) to measure interleukin 6 (IL-6), IL-8, superoxide dismutase (SOD) and malondialdehyde (MDA) levels. Myocardium samples were collected at 10-20 min after aorta cross-clamp (T₁) and at 10-20 min after the release of the aorta cross-clamp (T₂) to detect heme oxygenase-1 (HO-1) expression.

Results

Tracheal extubation time and length of ICU stay in PF group were significantly shorter than those of the MF group (p < 0.05, respectively). After cardiopulmonary bypass, IL-6, IL-8 and MDA levels were significantly increased, and the SOD level was significantly reduced in both two groups, but PF group exhibited lower IL-6, IL-8 and MDA levels and higher SOD levels than the MF group (p < 0.05, respectively). The HO-1 expression in the PF group was significantly higher than that in MF group at the corresponding time points (p < 0.05, respectively).

Conclusion

Propofol is superior to midazolam in reducing inflammation and oxidase stress and in improving post-operation recovery in children with congenital heart disease undergoing cardiac surgery.     

Left Ventricle Fibrosis Associated With Nonsustained Ventricular Tachycardia in an Elite Athlete: Is Exercise Responsible? A Case Report

Objective:

To emphasize the potentially harmful effects of high-intensity exercise on cardiac health and the fine line between physiologic and pathologic adaptation to chronic exercise in the elite athlete. This case also highlights the crucial need for regular evaluation of symptoms that suggest cardiac abnormality in athletes.

Background:

Sudden cardiac death (SCD) of young athletes is always a tragedy because they epitomize health. However, chronic, high-intensity exercise sometimes has harmful effects on cardiac health, and pathologic changes, such as myocardial fibrosis, have been observed in endurance athletes. In this case, a highly trained 30-year-old cyclist reported brief palpitations followed by presyncope feeling while exercising. Immediate investigations revealed nonsustained ventricular tachycardia originating from the left ventricle on a stress test associated with myocardial fibrosis of the left ventricle as shown with magnetic resonance imaging. Despite complete cessation of exercise, life-threatening arrhythmia and fibrosis persisted, leading to complete restriction from competition.

Differential Diagnosis:

Hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, myocarditis, postmyocarditis, use of drugs and toxic agents, doping, and systemic disease.

Treatment:

The arrhythmia could not be treated with catheter ablation procedure or drug suppression. Therefore, the athlete was instructed to withdraw completely from sport participation and to have a medical follow-up twice each year.

Uniqueness:

To our knowledge, no other report of left ventricle exercise-induced fibrosis associated with life-threatening arrhythmia in a living young elite athlete exists. Only postmortem evidence supports such myocardial pathologic adaptation to exercise.

Conclusions:

To prevent SCD in young athletes, careful attention must be paid to exercise-related symptoms that suggest a cardiac abnormality because they more often are linked to life-threatening cardiovascular disease.     

Native low-density lipoprotein-dependent interleukin-8 production through pertussis toxin-sensitive G-protein coupled receptors and hydrogen peroxide generation contributes to migration of human aortic smooth muscle cells

Purpose

Stimulation of human aortic smooth muscle cells (hAoSMCs) with native low-density lipoprotein (nLDL) induced the production of interleukin-8 (IL-8) that is involved in the pathogenesis of cardiovascular diseases. However, the process of signal transduction of nLDL was currently uncharacterized. Therefore, the aim of this study was to investigate the signal transduction pathway of nLDL-dependent IL-8 production and the effect of IL-8 on hAoSMCs migration.

Materials and Methods

nLDL was prepared by ultracentrifugation with density-adjusted human serum of normocholesterolemia. In hAoSMCs, IL-8 secreted to medium was measured using ELISA assay, and Western blot analysis was performed to detect p38 MAPK activation as a key regulator of IL-8 production. nLDL-dependent H₂O₂ generation was determined by microscopic analysis using 2'',7''-dichlorofluoroscein diacetate (DCF-DA). IL-8-induced migration of hAoSMCs was evaluated by counting the cell numbers moved to lower chamber using Transwell plates.

Results

nLDL-induced IL-8 production was completely blocked by preincubation of hAoSMCs with pertussis toxin (PTX), which inhibited nLDL-dependent p38 MAPK phosphorylation. PTX-sensitive G-protein coupled receptor was responsible for nLDL-dependent H₂O₂ generation that was abrogated with preincubation of the cells with of polyethylene glycol-conjugated catalase (PEG-Cat). Pretreatment of PEG-Cat prevented nLDL-induced p38 MAPK phosphorylation and IL-8 production, which was partly mimicked by treatment with exogenous H₂O₂. Finally, IL-8 increased hAoSMCs migration that was completely blocked by incubation with IL-8 neutralizing antibody.

Conclusion

PTX-sensitive G-protein coupled receptor-dependent H₂O₂ generation by nLDL plays a critical role in IL-8 production in hAoSMC, and IL-8 may contribute to atherogenesis through increased migration of hAoSMCs.     

Predictors of low cardiac output in decompensated severe heart failure

OBJECTIVE:

To identify predictors of low cardiac output and mortality in decompensated heart failure.

INTRODUCTION:

Introduction: Patients with decompensated heart failure have a high mortality rate, especially those patients with low cardiac output. However, this clinical presentation is uncommon, and its management is controversial.

METHODS:

We studied a cohort of 452 patients hospitalized with decompensated heart failure with an ejection fraction of <0.45. Patients underwent clinical‐hemodynamic assessment and Chagas disease immunoenzymatic assay. Low cardiac output was defined according to L and C clinical‐hemodynamic profiles. Multivariate analyses assessed clinical outcomes. P<0.05 was considered significant.

RESULTS:

The mean age was 60.1 years; 245 (54.2%) patients were >60 years, and 64.6% were men. Low cardiac output was present in 281 (63%) patients on admission. Chagas disease was the cause of heart failure in 92 (20.4%) patients who had higher B type natriuretic peptide levels (1,978.38 vs. 1,697.64 pg/mL; P = 0.015). Predictors of low cardiac output were Chagas disease (RR: 3.655, P<0.001), lower ejection fraction (RR: 2.414, P<0.001), hyponatremia (RR: 1.618, P = 0.036), and renal dysfunction (RR: 1.916, P = 0.007). Elderly patients were inversely associated with low cardiac output (RR: 0.436, P = 0.001). Predictors of mortality were Chagas disease (RR: 2.286, P<0.001), ischemic etiology (RR: 1.449, P = 0.035), and low cardiac output (RR: 1.419, P = 0.047).

CONCLUSIONS:

In severe decompensated heart failure, predictors of low cardiac output are Chagas disease, lower ejection fraction, hyponatremia, and renal dysfunction. Additionally, Chagas disease patients have higher B type natriuretic peptide levels and a worse prognosis independent of lower ejection fraction.     

Goal-directed fluid optimization based on stroke volume variation and cardiac index during one-lung ventilation in patients undergoing thoracoscopy lobectomy operations: a pilot study

OBJECTIVES:

This pilot study was designed to utilize stroke volume variation and cardiac index to ensure fluid optimization during one-lung ventilation in patients undergoing thoracoscopic lobectomies.

METHODS:

Eighty patients undergoing thoracoscopic lobectomy were randomized into either a goal-directed therapy group or a control group. In the goal-directed therapy group, the stroke volume variation was controlled at 10%±1%, and the cardiac index was controlled at a minimum of 2.5 L.min^-1.m^-2. In the control group, the MAP was maintained at between 65 mm Hg and 90 mm Hg, heart rate was maintained at between 60 BPM and 100 BPM, and urinary output was greater than 0.5 mL/kg^-1/h^-1. The hemodynamic variables, arterial blood gas analyses, total administered fluid volume and side effects were recorded.

RESULTS:

The PaO₂/FiO₂-ratio before the end of one-lung ventilation in the goal-directed therapy group was significantly higher than that of the control group, but there were no differences between the goal-directed therapy group and the control group for the PaO₂/FiO₂-ratio or other arterial blood gas analysis indices prior to anesthesia. The extubation time was significantly earlier in the goal-directed therapy group, but there was no difference in the length of hospital stay. Patients in the control group had greater urine volumes, and they were given greater colloid and overall fluid volumes. Nausea and vomiting were significantly reduced in the goal-directed therapy group.

CONCLUSION:

The results of this study demonstrated that an optimization protocol, based on stroke volume variation and cardiac index obtained with a FloTrac/Vigileo device, increased the PaO₂/FiO₂-ratio and reduced the overall fluid volume, intubation time and postoperative complications (nausea and vomiting) in thoracic surgery patients requiring one-lung ventilation.     

Effects of N-acetylcysteine on nicotinamide dinucleotide phosphate oxidase activation and antioxidant status in heart, lung, liver and kidney in streptozotocin-induced diabetic rats

Purpose

Hyperglycemia increases reactive oxygen species (ROS) and the resulting oxidative stress plays a key role in the pathogenesis of diabetic complications. Nicotinamide dinucleotide phosphate (NADPH) oxidase is one of the major sources of ROS production in diabetes. We, therefore, examined the possibility that NADPH oxidase activation is increased in various tissues, and that the antioxidant N-acetylcysteine (NAC) may have tissue specific effects on NADPH oxidase and tissue antioxidant status in diabetes.

Materials and Methods

Control (C) and streptozotocin-induced diabetic (D) rats were treated either with NAC (1.5 g/kg/day) orally or placebo for 4 weeks. The plasma, heart, lung, liver, kidney were harvested immediately and stored for biochemical or immunoblot analysis.

Results

levels of free 15-F_2t-isoprostane were increased in plasma, heart, lung, liver and kidney tissues in diabetic rats, accompanied with significantly increased membrane translocation of the NADPH oxidase subunit p67phox in all tissues and increased expression of the membrane-bound subunit p22phox in heart, lung and kidney. The tissue antioxidant activity in lung, liver and kidney was decreased in diabetic rats, while it was increased in heart tissue. NAC reduced the expression of p22phox and p67phox, suppressed p67phox membrane translocation, and reduced free 15-F_2t-isoprostane levels in all tissues. NAC increased antioxidant activity in liver and lung, but did not significantly affect antioxidant activity in heart and kidney.

Conclusion

The current study shows that NAC inhibits NADPH oxidase activation in diabetes and attenuates tissue oxidative damage in all organs, even though its effects on antioxidant activity are tissue specific.     

Aerobic exercise improves the inflammatory profile correlated with cardiac remodeling and function in chronic heart failure rats

OBJECTIVE:

The aim of the present study was to evaluate the effect of 8 weeks of aerobic exercise training on cardiac functioning and remodeling and on the plasma levels of inflammatory cytokines in chronic heart failure rats.

METHODS:

Wistar rats were subjected to myocardial infarction or sham surgery and assigned to 4 groups: chronic heart failure trained (n = 7), chronic heart failure sedentary (n = 6), sham trained (n = 8) and sham sedentary (n = 8). Four weeks after the surgical procedures, the rats were subjected to aerobic training in the form of treadmill running (50 min/day, 5 times per week, 16 m/min). At the end of 8 weeks, the rats were placed under anesthesia, the hemodynamic variables were recorded and blood samples were collected. Cardiac hypertrophy was evaluated using the left ventricular weight/body weight ratio, and the collagen volume fraction was assessed using histology.

RESULTS:

The chronic heart failure trained group showed a reduction in left ventricular end-diastolic pressure, a lower left ventricular weight/body weight ratio and a lower collagen volume fraction compared with the chronic heart failure sedentary group. In addition, exercise training reduced the plasma levels of TNF-α and IL-6 and increased the plasma level of IL-10.

CONCLUSION:

An 8-week aerobic exercise training program improved the inflammatory profile and cardiac function and attenuated cardiac remodeling in chronic heart failure rats.     

Piper Sarmentosum Increases Nitric Oxide Production in Oxidative Stress: A Study on Human Umbilical Vein Endothelial Cells

OBJECTIVE:

Nitric oxide produced by endothelial nitric oxide synthase (eNOS) possesses multiple anti-atherosclerotic properties. Hence, enhanced expression of eNOS and increased Nitric oxide levels may protect against the development of atherosclerosis. Piper sarmentosum is a tropical plant with antioxidant and anti-inflammatory activities. This study aimed to investigate the effects of Piper sarmentosum on the eNOS and Nitric oxide pathway in cultured human umbilical vein endothelial cells (HUVECs).

METHODS:

HUVECs were divided into four groups: control, treatment with 180 μM hydrogen peroxide (H₂O₂), treatment with 150 μg/mL aqueous extract of Piper sarmentosum, and concomitant treatment with aqueous extract of PS and H₂O₂ for 24 hours. Subsequently, HUVECs were harvested and eNOS mRNA expression was determined using qPCR. The eNOS protein level was measured using ELISA, and the eNOS activity and Nitric oxide level were determined by the Griess reaction.

RESULTS:

Human umbilical vein endothelial cells treated with aqueous extract of Piper sarmentosum showed a marked induction of Nitric oxide. Treatment with PS also resulted in increased eNOS mRNA expression, eNOS protein level and eNOS activity in HUVECs.

CONCLUSION:

Aqueous extract of Piper sarmentosum may improve endothelial function by promoting NO production in HUVECs.     

Association between muscle strength and the cardiopulmonary status of individuals living with HIV/AIDS

OBJECTIVE:

The purpose of this study was to compare aerobic function [anaerobic threshold (%V˙O₂-AT), respiratory compensation point (%V˙O₂-RCP) and peak oxygen uptake (V˙O_2peak)] between physically active patients with HIV/AIDS and matched controls and to examine associations between disease status, poor muscle strength, depression (as estimated by the profile of mood states questionnaire) and the aerobic performance of patients.

METHODS:

Progressive treadmill test data for %V˙O₂-AT (V-slope method), RCP and (V˙O_2peak) were compared between 39 male patients with HIV/AIDS (age 40.6±1.4 years) and 28 male controls (age 44.4±2.1 years) drawn from the same community and matched for habitual physical activity. Within-patient data were also examined in relation to CD4⁺ counts (nadir and current data) and peak isokinetic knee torque.

RESULTS:

AT, RCP and (V˙O_2peak) values were generally similar for patients and controls. Within the patient sample, binary classification suggested that AT, RCP and (V˙O_2peak) values were not associated with either the nadir or current CD4⁺ count, but treadmill test variables were positively associated with peak isokinetic knee torque.

CONCLUSION:

The aerobic performance of physically active patients with HIV/AIDS is generally well conserved. Nevertheless, poor muscle strength is observed in some HIV/AIDS patients, which is associated with lower anaerobic power and (V˙O_2peak), suggesting the possibility of enhancing the aerobic performance of patients with weak muscles through appropriate muscle-strengthening activities.