Bile acids (BAs) have considerable importance in the metabolism of glycolipid and cholesterol. BAs profile in mammals has been widely reported, but lacking in fishes. The purpose of the present study is to clarify BAs profiles of common carp and how exogenous additions of BAs could alleviate hepatopancreas injured of common carp under a high plant protein diet. A 11-week feeding trial was conducted with high plant protein diet (18%) (HP) and high plant protein diet (18%) added 600 mg/kg BAs (HP+BAs) for Common carp, and then the UHPLC-MS/MS technology was used to analyze the BAs in the bile and plasma of two groups.
HP could induce vacuolation of hepatocytes and accumulation of glycogen in Common carp, while these phenotypes were significantly improved in HP+BAs group. In addition, BAs profile of HP group and HP+BAs group were described in detail, for Common carp bile with treatment by exogenous BAs, TCA, CA, T β MCA and T ω MCA were the main components. Furthermore, in HP+BAs group plasma, CDCA, CA, LCA, and GCDCA increased significantly, they could activate TGR5, the activation of hepatopancreas TGR5 might regulate glucose metabolism to relieve hepatopancreas glycogen accumulation.
HP could induce glycogen accumulation in common carp hepatopancreas while supplemented BAs to HP could mitigate this symptom. And we determined that the reduction of common carp hepatopancreas glycogen accumulation in the HP+BAs group is importantly related to the change in the endogenous BAs profile after the addition of BAs in HP through an integrated bile acids profile determination by UHPLC-MS/MS . This study has important guiding significance for aquaculture.