Gene expression altered by high-fructose diet feeding and Chrebp deficiency

Epidemiologic and animal studies implicate overconsumption of fructose in the development of non-alcoholic fatty liver disease, but the molecular mechanisms underlying fructose-induced chronic liver diseases remains largely unknown. We present evidence supporting the essential function of the lipogenic transcription factor ChREBP in mediating adaptation response to fructose and protecting against fructose-induced hepatotoxicity. High-fructose diet (HFrD) activates hepatic lipogenesis via a ChREBP-dependent manner in wildtype mice, while inducing steatohepatitis in Chrebp-KO mice. In Chrebp-KO mouse livers, HFrD reduces levels of molecular chaperones and activates the CHOP-dependent unfolded protein response, whereas administration of chemical chaperone or Chop shRNA rescues liver injury. Gene expression profiling revealed elevated expression of cholesterol biosynthesis genes in Chrebp-KO livers after HFrD, in parallel with increased abundance of nuclear SREBP2. genes expression were compared between livers of wildtype mice fed 70%-fructose-diet v.s. regular chow, and between livers of Chrebp-/- mice v.s. wildtype mice fed 70%-fructose-diet. Micro-array assay was performed with RNA samples pooled from livers of regular chow-fed WT mice (n = 7) vs. HFrD-fed WT mice (n = 7) or from livers of HFrD-fed WT mice (n = 4) vs. HFrD-fed Chrebp-/- mice (n = 6). Both male and female mice are used in all 4 groups.