High-intensity interval training for treating pathological cardiac hypertrophy in spontaneously hypertensive rats: Effects and mechanisms
10.3969/j.issn.2095-4344.2692
- Author:
Guoqiang YUAN
1
Author Information
1. Department of Physical Education, Zhengzhou University of Aeronautics
- Publication Type:Journal Article
- Keywords:
Cardiac hypertrophy;
Cn/NFAT;
High-intensity interval training;
Hypertension;
PI3-K/Akt;
Rats;
Signal transduction pathway
- From:
Chinese Journal of Tissue Engineering Research
2020;24(23):3708-3715
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: Regular exercise training possesses health promotion effect. Low-to-moderate intensity continuous aerobic exercise has been an important strategy for primary and secondary prevention of chronic diseases such as hypertension; however, the effect of high-intensity interval training is still debated. OBJECTIVE: To explore the effects of high-intensity interval training on pathological cardiac hypertrophy and investigate the possible mechanism in spontaneously hypertensive rats. METHODS: Thirty male spontaneously hypertensive rats were randomly assigned into a control group and a training group. Fifteen Wistar-Kyoto rats were used as normotensive group. Rats in the normotensive and control group were housed at rest, while those in the training group were subjected to a high-intensity interval training lasting for 8 weeks. After experiment, blood pressure was detected using a non-invasive blood pressure tester, and cardiac structure and function were measured by echocardiogram. Histopathological detection was performed by hematoxylin-eosin and Masson staining to determine myocardial cross-sectional area. mRNA expression of fetal genes including atrial natriuretic peptide and brain natriuretic peptide were detected by RT-PCR. Protein expression of PI3-K, Akt, CnAβ and NFATc3 was detected using western blot assay. RESULTS AND CONCLUSION: Compared with the normotensive group, the blood pressure level was significantly elevated (P < 0.05), concentric hypertrophy in the left ventricle appeared (including narrowing of the left ventricular cavity, ventricular wall thickening, increasing of myocardial cross-sectional area), cardiac function reduced significantly (P < 0.05), mRNA of brain natriuretic peptide upregulated (P < 0.05), CnAβ protein raised (P < 0.05), p-NFATc3/t-NFATc3 ratio reduced (P < 0.05), and PI3-K(p110α) protein and p-Akt/t-Akt ratio had no significant changes (P > 0.05) in the control group. Compared with the control group, the blood systolic pressure was lowered (P < 0.05), eccentric hypertrophy (cardiac chamber extension) in the left ventricle occurred, cardiac function enhanced (P < 0.05), mRNA of brain natriuretic peptide downregulated (P < 0.05), PI3-K(p110α) protein and p-Akt/t-Akt ratio increased (P < 0.05), while CnAβ protein and p-NFATc3/t-NFATc3 ratio showed no significant difference in the training group (P > 0.05). Therefore, the 8-week high-intensity interval training can induce the transfer from pathological hypertrophy to physiological hypertrophy and enhance heart function in spontaneously hypertensive rats via the activation of PI3-K/Akt signal transduction pathway; however, the Cn/NFAT pathway cannot be inhibited.
