The role of endoplasmic reticulum stress and insulin resistance in the occurrence of goose fatty liver

• Endoplasmic reticulum stress can induce goose insulin resistance and fatty liver.
• Insulin resistance is induced in goose fatty liver by overfeeding.
• Endoplasmic reticulum stress is inhibited in overfeeding-induced goose fatty liver.
• The inhibited hepatic stress may be due to increased fatty acid desaturases.

In mammals, insulin resistance (IR) is required for the occurrence of non-alcoholic fatty liver disease, and endoplasmic reticulum stress (ERS) contributes to IR. As geese have physiological and metabolic characteristics different from mammals, it is unclear whether these mechanisms also underlie the occurrence of goose fatty liver. To address this, 70-day-old geese were treated with an ERS inducer or overfed, and variables associated with ERS or IR were subsequently determined. The data indicated that the group of geese treated with the ERS inducer for 20d appeared to be more intolerant to blood glucose than the control group, and their livers showed features of hepatic steatosis, suggesting ERS can induce IR and hepatic steatosis in geese. In contrast, overfeeding did not induce ERS, probably due to the upregulated expression of fatty acid desaturases, but induced higher fasting/postprandial blood glucose as well as glucose intolerance in geese, which was accompanied by a dramatic increase of liver weight. Taken together, these findings delineated the role of ERS and IR in the occurrence of goose fatty liver.