The involvement of monoacylglycerol O-acyltransferase 1 (MOGAT1) in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD) has been recognized. While exercise is recommended for the improvement of obesity and MASLD, the impact of exercise intensity remains unclear. This study aimed to examine the influence of exercise intensity on MOGAT1 expression in high-fat diet (HFD)-induced obese mice with MASLD.

Male C57BL/6 mice aged 6 weeks were subjected to either a regular or HFD with 60 % fat content for 8 weeks. The mice were categorized into 5 groups based on their diet and exercise intensity: normal diet group (ND), HFD group, low-intensity exercise with HFD group (HFD+LIE), moderate-intensity exercise with HFD group (HFD+MIE), and high-intensity exercise (HIE) with HFD group (HFD+HIE). The duration of running was adjusted to ensure uniform exercise load across groups (total distance = 900 m): HFD+LIE at 12 m/min for 75 min, HFD+MIE at 15 m/min for 60 min, and HFD+HIE at 18 m/min for 50 min.

Lipid droplet size and MASLD activity score were significantly lower in the HFD+HIE group compared to other exercise-intensity groups (p < 0.05). Among the 3 intensity exercise groups, the lowest MOGAT1 protein expression was found in the HFD+HIE group (p < 0.05).

This study reveals that high-intensity exercise has the potential to mitigate MASLD development, partly attributed to the downregulation of MOGAT1 expression.