Dexamethasone and Training-Induced Cardiac Remodeling Improve Cardiac Function and Arterial Pressure in Spontaneously Hypertensive Rats

Author(s)

Duchatsch, Francine ^[1] ; Tardelli, Lidieli P. ^[1] ; Herrera, Naiara A. ^[1] ; Ruiz, Thalles F. R. ^[2] ; Vicentini, Carlos A. ^[2] ; Okoshi, Katashi ^[3] ; Santos, Carlos F. ^[4] ; Amaral, Sandra L. ^{[1, 5]}

Affiliation

^[1] UNESP, PIPGCF UFSCar, Joint Grad Program Physiol Sci, Sao Carlos, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Sch Sci, Dept Biol Sci, Bauru, SP - Brazil

^[3] Sao Paulo State Univ UNESP, Botucatu Med Sch, Dept Internal Med, Botucatu, SP - Brazil

^[4] Univ Sao Paulo, Bauru Sch Dent, Dept Biol Sci, Bauru, SP - Brazil

^[5] Sao Paulo State Univ Unesp, Sch Sci, Dept Phys Educ, Bauru, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF CARDIOVASCULAR PHARMACOLOGY AND THERAPEUTICS; v. 26, n. 2 AUG 2020.
• Web of Science Citations: 1

Abstract

Introduction: Dexamethasone (DEX)-induced hypertension and cardiac remodeling are still unclear, especially in spontaneously hypertensive rats (SHR). On the other side, exercise training is a good strategy to control hypertension. Therefore, this study investigated the effects of DEX treatment and physical training on arterial pressure and cardiac remodeling in SHR. Material and Methods: SHR underwent treadmill training (5 days/week, 1h/session, at 50-60% of maximal capacity, 0% degree, 75 days) and received low-dose of DEX (50 mu g/kg,s.c.) during the last 15 days. Sedentary Wistar rats (W) were used as control. Echocardiography and artery catheterization were performed for cardiac remodeling and function, arterial pressure and autonomic nervous system analyses. In addition, left ventricle (LV) capillary density, myocyte diameter and collagen deposition area were analyzed using specific histological staining. Results: Low-dose of DEX treatment did not exacerbate arterial pressure of SHR and trained groups had lower values, regardless of DEX. DEX and training decreased relative left ventricle wall thickness (RWT) and determined LV angiogenesis (+19%) and lower collagen deposition area (-22%). In addition, it determined increased left ventricular diastolic diameter. These changes were followed by improvements on systolic and diastolic function, since it was observed increased posterior wall shortening velocity (PWSV) and reduced isovolumetric relaxation time (IVRT). Conclusion: In conclusion, this study is unique to indicate that low-dose of DEX treatment does not exacerbate arterial pressure in SHR and, when associated with training, it improves LV systolic and diastolic function, which may be due to LV angiogenesis and reduction of wall collagen deposition area. (AU)

• FAPESP's process: 18/00567-4 - Influence of empaglifozin on the heart of rats with myocardial infarction-induced cardiac remodeling
• Grantee: Katashi Okoshi
• Support Opportunities: Regular Research Grants
• FAPESP's process: 15/03965-2 - Role of the renin-angiotensin system in different oral inflammatory models: an experimental interdisciplinary and clinical approach
• Grantee: Carlos Ferreira dos Santos
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/14405-3 - Influence of aerobic physical training on cardiac remodeling of spontaneously hypertensive rats treated with dexamethasone
• Grantee: Francine Duchatsch Ribeiro de Souza
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 17/00509-1 - Role of physical training on autonomic balance, arterial stiffness and rarefaction in spontaneously hypertensive rats treated with dexamethasone: role of miRNA
• Grantee: Sandra Lia do Amaral Cardoso
• Support Opportunities: Regular Research Grants