1 - Efeito do treinamento preventivo no transcriptoma cardíaco de ratos com hipertensão pulmonar 2 - Tradução para o português da ferramenta syrcle de risco de viés

Abstract

Introduction 1: Induction of pulmonary hypertension (PH) by monocrotaline is common, which leads to increased right ventricular afterload, vascular remodeling, right ventricular hypertrophy and dysfunction, and ultimately heart failure. Physical exercise has long been recognized as a treatment for this condition. Although different mechanisms have been proposed to explain the development of PH, and the influence of preventive physical training, the analysis of the cardiac transcriptomic profile in this condition has not been explored. Objective: in this thesis we developed 2 scientific articles, one experimental (ARTICLE 1) and a translation of a risk of bias questionnaire (ARTICLE 2). Objective 1: to analyze the effect of preventive training on the global gene expression profile of the right ventricle in PH in rats. Twenty-four male Wistar rats (206-220 g) were divided into three groups (n=8/group): S, sedentary control; HPS, sedentary pulmonary hypertension; and TPH, group trained for pulmonary hypertension. The preventive training protocol was performed on a treadmill for 13 weeks. Cardiac hypertrophy by HP was experimentally induced by a single intraperitoneal injection (60 mg/kg) of monocrotaline after preventive training. Rats were evaluated 28 days after administration of monocrotaline. Left ventricular weight, right ventricular weight, and atrial weight normalized by body weight were used as indices of cardiac hypertrophy. Gene expression profiling was performed using the Rat Gene ST Array platform. To better understand the biological relevance of differentially expressed genes, we performed a functional enrichment analysis in the context of gene ontology (biological process, molecular function and cellular component) and networks (KEGG, Reactome, Wikipathways and BioPlanet). Results 1: Through the analysis of the cardiomyocytes area, the HP group presented cardiac hypertrophy, and the training softened this alteration p< 0.05. The global gene expression profile identified 687 differentially expressed genes (S vs. SPH) in right ventricular hypertrophy during PH, and when compared to preventive training, 91 genes were dysregulated (SPH vs. TPH). Analysis of the gene ontology in the expression profile data revealed changes in the genes that regulate the inflammatory process, muscle growth, metabolic processes, cell death and comparison of ionic regulation between HPS vs. TPH The genes that were altered in the PH hypertrophy phase and modified by exercise were platelet alpha granule lumen (Fgg and Qsox1 genes), NAD + binding (Cryl1 gene), cAMP-mediated signaling upregulation (Cxcl11 gene), upregulation of macrophage differentiation (IL34 gene), mRNA cleavage (Cstf3 gene), downregulation of transporter activity (Wwp2 gene), regulation of respiratory system process (Mtg2 gene) p< 0.05. Conclusion 1: Preventive training influences changes in cardiac gene expression profile in the hypertrophy phase of PH. New genes were identified, and these may be biomarkers and potential therapeutic targets in the initial phase of PH. Introduction 2: Experimental research has increased and meta-analysis has become frequent in Brazil and worldwide. In order to carry out these studies, the methodological quality is evaluated by important instruments such as the RoB-SYRCLE tool. Objective 2: translate RoB-SYRCLE for use in experimental studies. Methods 2: The translation of the tool was carried out following an international guide. After translation, back-translation and approval of the version by the creators, the tool, which is composed of 10 items, in Portuguese, was evaluated by 15 researchers with experience in animal studies. Items 1 and 2 refer to selection bias (sequence generation, baseline characteristics and allocation concealment), Items 3 and 4 to performance bias; item 5 for execution bias (random placement and blinding), Item 6 and 7 for detection bias (random assessment of outcomes and blinding), Item 8 for attrition bias (incomplete outcomes), item 9 for reporting bias (report of selective outcome) and item 10 to other sources of bias. The evaluators should respond in relation to the degree of understanding (I fully understood, I partially understood, I did not understand). Statistical analysis: descriptive statistics with percentage values. Results 2: Of the researchers who evaluated the tool, 100 to 86.6% fully understood items 1 to 7, 9 and 10. Regarding item 8, this was fully understood by 80% of the researchers. The RoB tool was successfully translated and used by all researchers, but still, adjustments and expert analysis are needed in question 8 due to the percentage of non-understanding being 20%.