The Effects of Glucose and Vitamin C on the Gene Expression of Lipoprotein Lipase and Hepatic Lipase During the Developement of the Yolk-Sac Larva of Carassius auratus gibelio

Abstract:

In this study we investigated the expression patterns of lipoprotein lipase and hepatic lipase genes, as well as the effects of the glucose solution and the vitamin C solution on its regulation during the development of the yolk-sac larva of Carassius auratus gibelio. In the preliminary experiments, the membrane break time and hatching rates were recorded to determine the optimal concentrations of glucose and vitamin C. Solutions without (control group) and with glucose (optimal concentration 15 g/L glucose group) or vitamin C (optimal concentration 30 mg/L vitamin C group) were used for hatching, and the gene expression patterns of lipoprotein lipase and hepatic lipase were analyzed. Real-time PCR was applied to measure the mRNA level of lipoprotein lipase and hepatic lipase, and to test how glucose and vitamin C regulated the expression of two genes during the development of the yolk-sac larva. We found that genes of lipoprotein lipase and hepatic lipase were expressed at the endogenous nutrition stage, the mixed nutrition stage and the exogenous nutrition stage, and that the expression was increased over time. The mRNA levels of both lipoprotein lipase and hepatic lipase were up-regulated from the endogenous nutrition stage to the exogenous nutrition stage in the group treated with 15 g/L glucose (P<0.05). Similarly they were also re-regulated from the endogenous nutrition stage to the exogenous nutrition stage in the group treated with 30 mg/L vitamin C, which caused a significant increase in the expression of lipoprotein lipase mRNA during the yolk-sac larva developmental stage. Vitamin C increased the expression of hepatic lipase mRNA during the mixed nutrition stage and the exogenous nutrition stage (P<0.05). Our study suggested that the lipid catabolism of C. auratus gibelio increased during the mixed nutrition stage, and that appropriate concentrations of glucose (15 g/L) and vitamin C (30 mg/L) could induce the mRNA expression of lipoprotein lipase and hepatic lipase.