Creatine ameliorates the adverse effects of high-fat diet on hepatic lipid metabolism, intestinal health, muscle growth and flesh quality in juvenile largemouth bass (Micropterus salmoides)

Abstract With the widespread use of high-fat diets (HFDs) in aquaculture, the adverse effects of HFDs on farmed fish are becoming increasingly apparent. Creatine has shown potential as a green feed additive in farmed fish; however, the potential of dietary creatine to attenuate adverse effects caused by high fat diets remains poorly understood. To address such gaps, the present study was conducted to investigate the mitigating effect of dietary creatine on HFD-induced disturbance on growth performance, hepatic lipid metabolism, intestinal health, as well as muscle quality of juvenile largemouth bass. Three diets were formulated: a control diet (10.20% lipid), a high fat diet (HFD, 18.31% lipid), and HFD with 2% creatine (HFD + creatine). Juvenile largemouth bass (3.73±0.01g) were randomly assigned to three diets for 10 weeks. The key findings were: (1) The expression of muscle growth-related genes and proteins was stimulated by dietary creatine, which contribute to ameliorate the adverse effects of HFD on growth performance; (2) Dietary creatine alleviates HFD-induced adverse effects on intestinal health by improving intestinal health, which also enhances feed utilization efficiency; (3) Dietary creatine causes excessive lipid deposition, mainly via lipolysis and β-oxidation. Notably, the present study also reveal a previously undisclosed effect of creatine supplementation on improving muscle quality. Together, first time from a comprehensive multi-organ or tissue perspective, our study provides a feasible approach for developing appropriate nutritional strategies to alleviate the adverse effects of HFD on farmed fish, based on creatine supplementation.