Glucose participates in the formation of goose fatty liver by regulating the expression of miRNA-33/CROT

Glucose oversupply promotes formation of fatty liver, and fatty liver is usually accompanied with hyperglycemia. However, the mechanism by which glucose promotes formation of fatty liver is not very clear. In this study, fatty liver was successfully induced in Landes goose by 19 days of overfeeding with corn-based feed, the overfed geese had a significantly higher level of blood glucose than the normally fed geese (control group). In goose primary liver cells, high level of glucose promoted fat deposition and induced the expression of SREBF2(or SREBP2), a key regulator of lipid metabolism, and its intronic gene, miR-33. Moreover, overexpression of miRNA-33(miR-33) promotes lipid accumulation in goose primary liver cells. Consistently, miR-33 inhibitor suppressed glucose induced lipid accumulation in liver cells. Interestingly, the relative abundance of miR-33 in goose fatty liver was significantly higher than that in normal liver, while the relative mRNA and protein abundances of CROT, the target gene of miR-33, in goose fatty liver were significantly lower than those in goose normal liver. Taken together, these findings suggest that miR-33 mediates glucose promotion of lipid accumulation in goose primary liver cells, and that glucose participates in formation of goose fatty liver by regulating the expression of miR-33/CROT.