Dietary Ferulic Acid Increases Endurance Capacity by Promoting Skeletal Muscle Oxidative Phenotype, Mitochondrial Function, and Antioxidant Capacity.

Scope: Endurance capacity is essential for endurance athletes' achievement and individuals' health. Nutritional supplements are a proven way to enhance endurance capacity. Previous studies have shown that ferulic acid (FA) enhances endurance capacity, but the underlying mechanism is unclear. The study is aimed to investigate the mechanism by which FA increases endurance capacity.

Methods And Results: Forty mice are divided into control and 0.5% FA-supplemented groups, and an exhaustive swimming test demonstrates increased endurance capacity with FA supplementation. This study investigates the underlying mechanism for this effect of FA. Firstly, RT-PCR and western blot analysis find that FA increases the transformation from fast to slow muscle fiber. Additionally, adenosine triphosphate concentration, metabolic enzyme activity, and mitochondrial DNA analysis find that FA increases mitochondrial biogenesis and activates nuclear factor erythroid 2-related factor (NRF)1 signaling pathway in muscle. Besides, through antioxidant capacity analysis, this study finds that FA activates NRF2 signaling pathway and improves the antioxidant capacity in muscle. Moreover, inhibiting NRF2 eliminates FA's effect on muscle fiber transformation in C2C12 cells.

Conclusion: Our results suggest that FA increases endurance capacity by promoting skeletal muscle oxidative phenotype, mitochondrial function, and antioxidant capacity, which may be related to the NRF1 and NRF2 signaling pathways.