Genome-wide transcriptome expression in the liver of a mouse model of high carbohydrate diet-induced liver steatosis and its significance for the disease.

Purpose: To perform a large-scale gene profiling of the liver in a mouse model of fatty liver induced by high carbohydrate (sucrose) diet (HCD) to gain a deeper insight into potential mechanisms of diet-induced hepatic steatosis.

Methods: C57BL/6 male mice were fed either a purified, control diet or a HCD for 16 weeks. HCD feeding led to marked liver steatosis without inflammation or necrosis. The expression of 42,500 genes/sequences was assessed.

Results: A number of genes (471) underwent significant expression changes in HCD- as compared to standard diet-fed mice (n = 5/group; P < 0.01). Of these genes, 211 were down- and 260 up-regulated. The latter group includes 20 genes encoding enzymes involved in carbohydrate conversion to fat. The genes that underwent expression changes perform a large variety of molecular functions, and the vast majority of these have never been tested before in non-alcoholic fatty liver of nutritional origin. They reveal novel aspects of the disease and allow identification of candidate genes that may underlie the initiation of hepatic steatosis and progression to non-alcoholic steatohepatitis.

Conclusions: HCD-fed laboratory animals provide a model of early non-alcoholic fatty liver disease resembling the disease in humans. The genome wide gene profiling of the liver reveals the complexity of the disease, unravels novel aspects of HCD-induced hepatic steatosis, and helps elucidate its nature and mechanisms.