Effect of High-Intensity Interval Training and High-Fat Diet on Nrg-1 and Pgc-1α in Aging Rats’ Heart Tissue

Abstract

Objective: Neuregulin is activated by exercise and has been implicated as a mediator of the beneficial effects of exercise training on metabolism. The aim of this study was to effect of high-intensity interval training and high-fat diet on NRG-1 and PGC-1α in aging rats’ heart tissue.

Materials and Methods: 20 male Wistar rats aged 48 to 52 weeks were purchased and kept inside standard cages at a temperature of 22±2 degrees Celsius. After one week of acclimatization to the laboratory environment, the animals were divided into four groups (normal diet, normal diet+training, high-fat diet, and high-fat diet+ training). According to the research design, the training group underwent 8 weeks of training. This was followed by high-intensity interval training at an intensity of 85% to 90% of VO2max. Two-way ANOVA (DIET×HIIT) were used to examine (P<0.05).

Results: The findings indicated a High-fat diet had a significant and decreasing effect on NRG-1 (p=0.004, F=11.17). Exercise did not have a significant effect (p=0.039, F=5.04) on NRG-1, although it increased NRG-1 levels. The interactive effect of diet and exercise on NRG-1 was not statistically significant (p=0.93, F=0.008). The findings indicate that diet reduced and exercise increased NRG-1 levels. In fact, the effect of exercise in the high-fat diet group reduced the differences and led to non-significant results statistically.

Conclusion: Eight weeks of HIIT training, along with a normal diet, led to an increase in the expression of neuregulin in the heart tissue of aged mice. The expression of PGC-1α also increased following the HIIT. This increase can be attributed to the increased neuregulin expression, leading to improved mitochondrial biogenesis.