Aerobic Swim Training Restores Aortic Endothelial Function by Decreasing Superoxide Levels in Spontaneously Hypertensive Rats

Authors

  • Camila P. Jordão Universidade de São Paulo; Hospital das Clinicas HCFMUSP, Faculdade de Medicina; Unidade de Reabilitação, Instituto do Coracao (InCor)
  • Tiago Fernandes Universidade de São Paulo; Escola de Educacao Fisica e Esporte; Laboratorio de Bioquimica e Biologia Molecular do Exercicio
  • Leonardo Yuji Tanaka Universidade de São Paulo; Hospital das Clinicas HCFMUSP, Faculdade de Medicina; Laboratorio de Biologia Vascular, Instituto do Coracao (InCor)
  • Luiz R. Grassmann Bechara Universidade de São Paulo; Escola de Educacao Fisica e Esporte; Laboratorio de Bioquimica e Biologia Molecular do Exercicio
  • Luis Gustavo Oliveira de Sousa Universidade de São Paulo; Escola de Educacao Fisica e Esporte; Laboratorio de Bioquimica e Biologia Molecular do Exercicio
  • Edilamar M. Oliveira Universidade de São Paulo; Escola de Educacao Fisica e Esporte; Laboratorio de Bioquimica e Biologia Molecular do Exercicio
  • Paulo Rizzo Ramires Universidade de São Paulo; Escola de Educacao Fisica e Esporte; Laboratorio de Bioquimica e Biologia Molecular do Exercicio

DOI:

https://doi.org/10.6061/clinics/2017(05)09

Keywords:

Aerobic Training, Vasodilation, Nitric Oxide, Superoxide, Hypertension

Abstract

OBJECTIVE: We aimed to determine whether aerobic training decreases superoxide levels, increases nitric oxide levels, and improves endothelium-dependent vasodilation in the aortas of spontaneously hypertensive rats. METHODS: Spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY) were distributed into 2 groups: sedentary (SHRsd and WKYsd, n=10 each) and swimming-trained (SHRtr, n=10 and WKYtr, n=10, respectively). The trained group participated in training sessions 5 days/week for 1 h/day with an additional work load of 4% of the animal’s body weight. After a 10-week sedentary or aerobic training period, the rats were euthanized. The thoracic aortas were removed to evaluate the vasodilator response to acetylcholine (10-10 to 10-4 M) with or without preincubation with L-NG-nitro-L-arginine methyl ester hydrochloride (L-NAME; 10-4 M) in vitro. The aortic tissue was also used to assess the levels of the endothelial nitric oxide synthase and nicotinamide adenine dinucleotide oxidase subunit isoforms 1 and 4 proteins, as well as the superoxide and nitrite contents. Blood pressure was measured using a computerized tail-cuff system. RESULTS: Aerobic training significantly increased the acetylcholine-induced maximum vasodilation observed in the SHRtr group compared with the SHRsd group (85.9±4.3 vs. 71.6±5.2%). Additionally, in the SHRtr group, superoxide levels were significantly decreased, nitric oxide bioavailability was improved, and the levels of the nicotinamide adenine dinucleotide oxidase subunit isoform 4 protein were decreased compared to the SHRsd group. Moreover, after training, the blood pressure of the SHRtr group decreased compared to the SHRsd group. Exercise training had no effect on the blood pressure of the WKYtr group. CONCLUSIONS: In SHR, aerobic swim training decreased vascular superoxide generation by nicotinamide adenine dinucleotide oxidase subunit isoform 4 and increased nitric oxide bioavailability, thereby improving endothelial function.

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Published

2017-05-01

Issue

Section

Basic Research

How to Cite

Jordão, C. P., Fernandes, T., Tanaka, L. Y., Bechara, L. R. G., de Sousa, L. G. O., Oliveira, E. M., & Ramires, P. R. (2017). Aerobic Swim Training Restores Aortic Endothelial Function by Decreasing Superoxide Levels in Spontaneously Hypertensive Rats. Clinics, 72(5), 310-316. https://doi.org/10.6061/clinics/2017(05)09