Myocardial proteome changes in aortic stenosis rats subjected to long-term aerobic exercise.

The effects of exercise training (ET) on the heart of aortic stenosis (AS) rats are controversial and the mechanisms involved in alterations induced by ET have been poorly clarified. In this study, we analyzed the myocardial proteome to identify proteins modulated by moderate-intensity aerobic ET in rats with chronic supravalvular AS. Wistar rats were divided into four groups: sedentary control (C-Sed), exercised control (C-Ex), sedentary aortic stenosis (AS-Sed), and exercised AS (AS-Ex). ET consisted of five treadmill running sessions per week for 16 weeks. Statistical analysis was performed by ANOVA or Kruskal-Wallis and Goodman tests. Results were discussed at a significance level of 5%. At the end of the experiment, AS-Ex rats had higher functional capacity, lower blood lactate concentration, and better cardiac structural and left ventricular (LV) functional parameters than the AS-Sed. Myocardial proteome analysis showed that AS-Sed had higher relative protein abundance related to the glycolytic pathway, oxidative stress, and inflammation, and lower relative protein abundance related to beta-oxidation than C-Sed. AS-Ex had higher abundance of one protein related to mitochondrial biogenesis and lower relative protein abundance associated with oxidative stress and inflammation than AS-Sed. Proteomic data were validated for proteins related to lipid and glycolytic metabolism. Chronic pressure overload changes the abundance of myocardial proteins that are mainly involved in lipid and glycolytic energy metabolism in rats. Moderate-intensity aerobic training attenuates changes in proteins related to oxidative stress and inflammation and increases the COX4I1 protein, related to mitochondrial biogenesis. Protein changes are combined with improved functional capacity, cardiac remodeling, and LV function in AS rats.

The influence of dapagliflozin on cardiac remodeling, myocardial function and metabolomics in type 1 diabetes mellitus rats.

BACKGROUND: Sodium-glucose cotransporter (SGLT)2 inhibitors have displayed beneficial effects on the cardiovascular system in diabetes mellitus (DM) patients. As most clinical trials were performed in Type 2 DM, their effects in Type 1 DM have not been established. OBJECTIVE: To evaluate the influence of long-term treatment with SGLT2 inhibitor dapagliflozin on cardiac remodeling, myocardial function, energy metabolism, and metabolomics in rats with Type 1 DM. METHODS: Male Wistar rats were divided into groups: Control (C, n = 15); DM (n = 15); and DM treated with dapagliflozin (DM + DAPA, n = 15) for 30 weeks. DM was induced by streptozotocin. Dapagliflozin 5 mg/kg/day was added to chow. STATISTICAL ANALYSIS: ANOVA and Tukey or Kruskal-Wallis and Dunn. RESULTS: DM + DAPA presented lower glycemia and higher body weight than DM. Echocardiogram showed DM with left atrium dilation and left ventricular (LV) hypertrophy, dilation, and systolic and diastolic dysfunction. In LV isolated papillary muscles, DM had reduced developed tension, +dT/dt and -dT/dt in basal condition and after inotropic stimulation. All functional changes were attenuated by dapagliflozin. Hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) activity was lower in DM than C, and PFK and PK activity higher in DM + DAPA than DM. Metabolomics revealed 21 and 5 metabolites positively regulated in DM vs. C and DM + DAPA vs. DM, respectively; 6 and 3 metabolites were negatively regulated in DM vs. C and DM + DAPA vs. DM, respectively. Five metabolites that participate in cell membrane ultrastructure were higher in DM than C. Metabolites levels of N-oleoyl glutamic acid, chlorocresol and N-oleoyl-L-serine were lower and phosphatidylethanolamine and ceramide higher in DM + DAPA than DM. CONCLUSION: Long-term treatment with dapagliflozin attenuates cardiac remodeling, myocardial dysfunction, and contractile reserve impairment in Type 1 diabetic rats. The functional improvement is combined with restored pyruvate kinase and phosphofructokinase activity and attenuated metabolomics changes.

Efficacy of BREATHOX® Device Inhalation on Acute Symptoms Associated with COVID-19 (BREATH Study): A Randomized Pilot Clinical Trial.

(1) Background: A high concentration of sodium chloride on in vitro cell culture leads to reduced SARS-CoV-2 replication. Therefore, our aim was to evaluate the effects of inhaling hypertonic NaCl particles (BREATHOX®) on the duration of COVID-19-induced acute symptoms. (2) Methods: A prospective, open label, randomized, standard of care-controlled group (SOC) pilot trial compared inhaled oral and nasal administered BREATHOX® (2.0 mg NaCl, particles size between 1-10 µm), with five or ten inhalations per day for ten days. The primary endpoint was the time to resolve COVID-19-related symptoms. Safety outcomes included adverse clinical and laboratory events. (3) Results: A total of 101 individuals were screened and 98 were randomly assigned to BREATHOX® ten sessions per day (Group 1; 33 patients), BREATHOX® five sessions per day (Group 2; 32 patients), or SOC (33 patients), and followed up for 28 days. There was an association with cough frequency after 10 days BREATHOX® compared to SOC [Group 1: hazard ratio (HR) 2.01, 95% confidence interval (CI) 1.06-3.81; Group 2: HR 2.17, 95% CI 1.17-4.04]. No differences between the groups for the reported symptoms' resolution time were seen after 28 days. After combining both BREATHOX® groups, the period to cough resolution 10 days after randomization was significantly lower than in SOC (HR 2.10, 95% CI 1.20-3.67). An adverse event occurred in 30% of Group 1, 36% of Group 2, and 9% in SOC individuals. One patient from SOC had a serious adverse event. Nasal burning, sore or itchy nose, and dry mouth were considered related to BREATHOX® use and resolved after stopping inhalations. (4) Conclusion: BREATHOX® inhalation is safe and may be effective in reducing the duration of COVID-19-induced coughing.

Oxidative stress evaluation in patients with chronic Chagas disease.

INTRODUCTION: Chagas disease (CD), caused by protozoan Trypanosoma cruzi (T. cruzi), is a neglected disease that affects millions of people worldwide. The parasite clearance by the immune cells is accomplished by the activation of inflammation and production of reactive oxygen species, including nitric oxide (NO) that can lead to tissue injury and DNA damage. On the other hand, to balance the oxidative environment and decrease free radicals, there is an antioxidant system composed of enzymes and vitamins. The aim was to evaluate oxidative stress parameters in symptomatic and asymptomatic patients with Chagas disease. METHODS: Participants were divided into three groups: indeterminate CD (asymptomatic, n = 8), CD with cardiac/digestive involvement (symptomatic, n = 14), and Control healthy individuals (n = 20). The following parameters were analyzed: DNA damage, NO serum levels, hydrophilic antioxidant capacity (HAC) and vitamin E. RESULTS: Symptomatic patients showed increased DNA damage and NO levels and lower HAC and vitamin E levels compared to asymptomatic patients and control subjects. CONCLUSIONS: It is possible to conclude that CD patients with clinical symptoms have higher oxidative stress, characterized by increased DNA damage and NO levels, and reduced antioxidant capacity and vitamin E levels.

Effects of Resistance Exercise on Slow-Twitch Soleus Muscle of Infarcted Rats.

Although current guidelines recommend resistance exercise in combination with aerobic training to increase muscle strength and prevent skeletal muscle loss during cardiac remodeling, its effects are not clear. In this study, we evaluated the effects of resistance training on cardiac remodeling and the soleus muscle in long-term myocardial infarction (MI) rats. METHODS: Three months after MI induction, male Wistar rats were assigned to Sham (n = 14), MI (n = 9), and resistance exercised MI (R-MI, n = 13) groups. The rats trained three times a week for 12 weeks on a climbing ladder. An echocardiogram was performed before and after training. Protein expression of the insulin-like growth factor (IGF)-1/protein kinase B (Akt)/rapamycin target complex (mTOR) pathway was analyzed by Western blot. RESULTS: Mortality rate was higher in MI than Sham; in the R-MI group, mortality rate was between that in MI and Sham and did not differ significantly from either group. Exercise increased maximal load capacity without changing cardiac structure and left ventricular function in infarcted rats. Infarction size did not differ between infarcted groups. Catalase activity was lower in MI than Sham and glutathione peroxidase lower in MI than Sham and R-MI. Protein expression of p70S6K was lower in MI than Sham and p-FoxO3 was lower in MI than Sham and R-MI. Energy metabolism did not differ between groups, except for higher phosphofrutokinase activity in R-MI than MI. CONCLUSION: Resistance exercise is safe and increases muscle strength regardless structural and functional cardiac changes in myocardial-infarcted rats. This exercise modality attenuates soleus glycolytic metabolism changes and improves the expression of proteins required for protein turnover and antioxidant response.

The Role of Oxidative Stress in the Aging Heart.

Medical advances and the availability of diagnostic tools have considerably increased life expectancy and, consequently, the elderly segment of the world population. As age is a major risk factor in cardiovascular disease (CVD), it is critical to understand the changes in cardiac structure and function during the aging process. The phenotypes and molecular mechanisms of cardiac aging include several factors. An increase in oxidative stress is a major player in cardiac aging. Reactive oxygen species (ROS) production is an important mechanism for maintaining physiological processes; its generation is regulated by a system of antioxidant enzymes. Oxidative stress occurs from an imbalance between ROS production and antioxidant defenses resulting in the accumulation of free radicals. In the heart, ROS activate signaling pathways involved in myocyte hypertrophy, interstitial fibrosis, contractile dysfunction, and inflammation thereby affecting cell structure and function, and contributing to cardiac damage and remodeling. In this manuscript, we review recent published research on cardiac aging. We summarize the aging heart biology, highlighting key molecular pathways and cellular processes that underlie the redox signaling changes during aging. Main ROS sources, antioxidant defenses, and the role of dysfunctional mitochondria in the aging heart are addressed. As metabolism changes contribute to cardiac aging, we also comment on the most prevalent metabolic alterations. This review will help us to understand the mechanisms involved in the heart aging process and will provide a background for attractive molecular targets to prevent age-driven pathology of the heart. A greater understanding of the processes involved in cardiac aging may facilitate our ability to mitigate the escalating burden of CVD in older individuals and promote healthy cardiac aging.

Relationship Between Lipodystrophy, Body Composition, Metabolic Profile, and Serum Levels of Adipocytokines.

Background: Despite the benefits in improving the clinical state of people living with HIV/aids (PLWHA), some side effects associated with the use of antiretroviral therapy (ART) are reported. Redistribution of body fat has been associated with treatment and is characterized by morphological changes, also known as lipodystrophy. The complications of metabolic and morphological changes in these individuals seem to increase the risk of cardiovascular disease. Adipocytokines are proteins that have essential functions in biological processes, in which the levels of these proteins are related to the pathogenesis of metabolic syndrome (MS) and cardiovascular disease. Recent studies have shown that such levels are generally modified in PLWHA, regardless of whether the treatment is established or not. An application of methods for body fat estimation in patients with fat redistribution, as in the case of aids, especially those that quantify body fat by segments, appears to clarify these alterations and plays an important role in the development of multiprofessional treatment. Objectives: This investigation was carried out to compare and correlate body composition, biochemical metabolic parameters, and levels of adipocytokines and cytokines of PLWHA, with and without lipodystrophy, with individuals with negative HIV serology and stratified by sex. Material and Methods: This is a cross-sectional study in which body composition, metabolic and anthropometric changes, and levels of adipocytokines of 110 individuals were assessed. These individuals were paired in sex, age, and body mass index (BMI) and subdivided into three groups: PLWHA with and without a clinical diagnosis of lipodystrophy associated with HIV, and a group control. Results: Collinearity was identified both in the general sample and for genders of the waist-to-height ratio (WHtR) with all anthropometric parameters, except for muscle mass. The results show strong association between IFN-γ and TNF-α both in the general sample and for genders and moderate correlation between leptin and fasting glucose for women; worsening of the triglyceride profile in both women with lipodystrophy compared with the control group and men without lipodystrophy compared with the control group; higher serum TNF-α values among men without lipodystrophy compared to those with HIV-associated lipodystrophy (HALS). Conclusions: The results of this study underline that, considering the manifestations of the syndrome, these patients have a high-risk endocrine metabolic profile for cardiovascular events.

Effects of Late Aerobic Exercise on Cardiac Remodeling of Rats with Small-Sized Myocardial Infarction. / Efeitos do Exercício Aeróbico Tardio na Remodelação Cardíaca de Ratos com Infarto do Miocárdio Pequeno.

BACKGROUND: Physical exercise has been considered an important non-pharmacological therapy for the prevention and treatment of cardiovascular diseases. However, its effects on minor cardiac remodeling are not clear. OBJECTIVE: To evaluate the influence of aerobic exercise on the functional capacity, cardiac structure, left ventricular (LV) function, and gene expression of NADPH oxidase subunits in rats with small-sized myocardial infarction (MI). METHODS: Three months after MI induction, Wistar rats were divided into three groups: Sham; sedentary MI (MI-SED); and aerobic exercised MI (MI-AE). The rats exercised on a treadmill three times a week for 12 weeks. An echocardiogram was performed before and after training. The infarction size was evaluated by histology, and gene expression was assessed by RT-PCR. The significance level for statistical analysis was set at 5%. RESULTS: Rats with MI lower than 30% of the LV total area were included in the study. Functional capacity was higher in MI-AE than in Sham and MI-SED rats. The infarction size did not differ between groups. Infarcted rats had increased LV diastolic and systolic diameter, left atrial diameter, and LV mass, with systolic dysfunction. Relative wall thickness was lower in MI-SED than in the MI-AE and Sham groups. Gene expression of the NADPH oxidase subunits NOX2, NOX4, p22phox, and p47phox did not differ between groups. CONCLUSION: Small-sized MI changes cardiac structure and LV systolic function. Late aerobic exercise is able to improve functional capacity and cardiac remodeling by preserving the left ventricular geometry. NADPH oxidase subunits gene expression is not involved in cardiac remodeling or modulated by aerobic exercise in rats with small-sized MI.

FUNDAMENTO: O exercício físico tem sido considerado uma importante terapia não farmacológica para a prevenção e tratamento das doenças cardiovasculares. No entanto, seus efeitos na remodelação cardíaca leve não são claros. OBJETIVO: Avaliar a influência do exercício aeróbico sobre a capacidade funcional, estrutura cardíaca, função ventricular esquerda (VE) e expressão gênica das subunidades da NADPH oxidase em ratos com infarto do miocárdio pequeno (IM). MÉTODOS: Três meses após a indução do IM, ratos Wistar foram divididos em três grupos: Sham; IM sedentário (IM-SED); e IM exercício aeróbico (IM-EA). Os ratos se exercitaram em uma esteira três vezes por semana durante 12 semanas. Um ecocardiograma foi realizado antes e após o treinamento. O tamanho do infarto foi avaliado por histologia e a expressão gênica por RT-PCR. O nível de significância para análise estatística foi estabelecido em 5%. RESULTADOS: Ratos com IM menor que 30% da área total do VE foram incluídos no estudo. A capacidade funcional foi maior no IM-EA do que nos ratos Sham e IM-SED. O tamanho do infarto não diferiu entre os grupos. Ratos infartados apresentaram aumento do diâmetro diastólico e sistólico do VE, diâmetro do átrio esquerdo e massa do VE, com disfunção sistólica. A espessura relativa da parede foi menor no grupo IM-SED do que nos grupos IM-EA e Sham. A expressão gênica das subunidades NADPH oxidase NOX2, NOX4, p22phox e p47phox não diferiu entre os grupos. CONCLUSÃO: Infarto do miocárdio pequeno altera a estrutura cardíaca e a função sistólica do VE. O exercício aeróbico tardio pode melhorar a capacidade funcional e a remodelação cardíaca por meio da preservação da geometria ventricular esquerda. A expressão gênica das subunidades da NADPH oxidase não está envolvida na remodelação cardíaca, nem é modulada pelo exercício aeróbico em ratos com infarto do miocárdio pequeno.