Sodium acetate alleviates the liver injury induced by high carbohydrate diets in swamp eel Monopterus albus through inhibiting inflammation formation

Optimal carbohydrate level in diets could improve growth and feed efficiency, whereas HC (high carbohydrate) diets usually induce the liver injury in reared fish. While SA (sodium acetate) has demonstrated its potential to alleviate liver injury in mammals, the mechanism underlying its impact on liver health in fish remains elusive. This study aims to elucidate the effect of dietary SA on liver injury in the female Monopterus albus. In our study, groups of M. albus were fed with different diets: NC (normal, 20% carbohydrate), HC (high carbohydrate, 32% carbohydrate) and HC+A (HC supplemented with 0.2% SA) diets, in separate, for a consecutive period of 56 days. Our findings showed that HC+A diets improved growth (weight gain rate, from 263.27 +/- 9.87-292.34 +/- 6.18%) and FE (feed efficiency, from 67.28 +/- 2.18-75.91 +/- 1.90%) (P < 0.05). Simultaneously, HC+A diets alleviated the liver injury caused by HC diets, including the decrease of serum AST (aspartate aminotransferase) (P < 0.05). Meanwhile, HC-A diets decreased the relative areas of hepatic glycogen compared with the HC diets by histological analysis (P < 0.05). In addition, the transcriptomic analysis of DEG (differentially expressed genes) in liver showed that all the DEG involved in anti-inflammatory (PPAR alpha, APOA-I) were up-regulated in HC+A group compared with NC and HC group (P < 0.05). In general, sodium acetate could improve the liver injury induced by HC diets of swamp eel through inhibiting the formation of inflammatory. Our results indicated that sodium acetate can be used as a functional additive in the application of aquatic HC diets.