Programming of high-glucose diet acceptance in Chinese perch (Siniperca Chuatsi) following an early exposure

Abstract

As a carnivorous fish, Chinese perch have a poor ability to utilize carbohydrate. To explore the effect of glucose exposure on glucose and lipid metabolism in larval Chinese perch, as well as on the domestication with high-starch artificial diet in juvenile fish. After a short-term glucose immersion, the growth performance, glucose and lipid metabolism, and DNA methylation level of glucose metabolism relative genes were measured. After a 3-month normal feeding trial, the success rate of domestication and the feed intake were examined. Success rate of feed intake and growth performance (the total length, body length and weight) in larval and juvenile fish in GLU group were all significantly higher than CON group (P<0.05). In larval fish, the expressions of insra, insrb and glycolysis relative gene (pk), glycogenolysisre relative gene (gp) in GLU group were significantly up-regulated, while gluconeogenesis relative genes (pepck and g6pca1), glycogenesis relative genes (gs) in GLU group were significantly down-regulated compared to CON group (P<0.05). The expressions of fatty acid synthesis relative genes (srebp1, acc1, and fas) in GLU group were all significantly up-regulated compared to CON group, while β-oxidation relative genes (pparα and cpt1) were significantly down-regulated (P<0.05). The DNA methylation levels of pepck and pk in GLU group were both significantly higher than CON group (P<0.05). A glucose exposure in Chinese perch during the early development stage improved utilization of glucose in larval fish by increasing insulin, glycolysis, and glycogen decomposition, inhibiting gluconeogenesis and glycogen synthesis, which might be associated with glucose metabolism relative genes (pk and pepck) regulated by DNA methylation. And the glucose exposure increased fatty acid synthesis, decreased β-oxidation in larval fish. Furthermore, the success rate of feed intake and growth was enhanced. This glucose programming continuously enhanced acceptance high-glucose diet and growth in juvenile Chinese perch.