AUTHOR=He Yuhang , Fu Zhengyi , Dai Shiming , Yu Gang , Ma Zhenhua 

TITLE=Dietary curcumin supplementation can enhance health and resistance to ammonia stress in the greater amberjack (Seriola dumerili)

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2022.961783

DOI=10.3389/fmars.2022.961783

ISSN=2296-7745

ABSTRACT=We evaluated the effect of dietary curcumin supplementation on the antioxidant capacity of the liver and the resistance of the liver and spleen to ammonia stress in the great amberjack (Seriola dumerili). Three isonitrogenous and isolipidic test diets were prepared by supplementing incremental levels of dietary curcumin at 0 mg/kg (CUR0%, control), 100 mg/kg (CUR0.01%) and 200 mg/kg (CUR0.02%), respectively. Each diet was randomly assigned to triplicate groups of 15 fish per tank. At the end of the feeding experiment, dietary curcumin supplementation positively modulated antioxidant-related genes and enzyme activity in liver tissues. After the ammonia challenge, dietary supplementation with the appropriate level of curcumin alleviated ammonia stress in liver tissue by up-regulating the relative expression of GSH-Px and downregulating the relative expression of Keap1 and GR. While ammonia stress in spleen tissue could also be alleviated by up-regulating the relative expression of CAT, down-regulating the relative expression of GR, and increasing the activity of SOD and GSH. After the recovery, dietary supplemented with curcumin still alleviated ammonia stress in liver tissue by up-regulating the relative expression of CAT, down-regulating the relative expression of Keap1 and GR, and increasing the activity of SOD and GSH. While ammonia stress in spleen tissue was still alleviated by up-regulating the relative expression of Mn-SOD, increasing the activity of the SOD and GSH. Histological structure results also showed the liver cell in the curcumin-containing groups exhibited the positive impact on cell boundaries, alignment, and nuclei after the ammonia challenge and recovery. Spleen cells in the curcumin-containing groups exhibited greater aggregation of melano-macrophage centres after ammonia challenge and recovery. These results suggest that dietary curcumin supplementation at 100 mg/kg can promote the health condition and resistance to ammonia stress of the greater amberjack.