title: E2F8 promotes hepatic steatosis through FABP3 expression in diet-induced obesity in zebrafish.
abstract: BACKGROUND
  Diet-induced hepatic steatosis is highly associated with nonalcoholic fatty liver disease, which is related to the development of metabolic syndrome. While advanced stage nonalcoholic hepatic steatosis and steatohepatitis (NASH) result ultimately in fibrosis and cirrhosis, the molecular basis for lipid droplet formation is poorly understood. Common pathways underlie the pathology of mammalian obesity and the zebrafish diet-induced obesity model (DIO-zebrafish) used in this study.
  
  
  METHODS
  Our analysis involved a combination of transcriptome (DNA microarray) and proteome (two-dimensional electrophoresis) methods using liver tissue from DIO-zebrafish to find candidate genes involved in hepatic steatosis. We conducted intraperitoneal injection (i.p.) of morpholino antisense oligonucleotides (MOs) for each gene into DIO-zebrafish. We also conducted in vitro overexpression in human cells. Additionally, we examined gene expression during feeding experiments involving anti-obesity compounds, creatine and anserine.
  
  
  RESULTS
  We found that fatty acid binding protein 3 (fabp3) and E2F transcription factors were upregulated in hepatic steatosis. E2f8 MO i.p. suppressed fabp3 expression in liver, and ameliorated hepatic steatosis. In human cells (HepG2), E2F8 overexpression promoted FABP3 expression. Additionally, co-administration of creatine and anserine suppressed obesity associated phenotypes including hepatic steatosis as indicated by e2f8 and fabp3 down regulation.
  
  
  CONCLUSIONS
  We discovered that the e2f8-fabp3 axis is important in the promotion of hepatic steatosis in DIO-zebrafish. The combination of transcriptome and proteome analyses using the disease model zebrafish allow identification of novel pathways involved in human diseases.
authors.affiliation: Department of Molecular and Cellular Pharmacology, Pharmacogenomics and Pharmacoinformatics, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie Japan ; Department of Systems Pharmacology, Mie University Graduate School of Medicine, Mie, Japan ; Mie University Medical Zebrafish Research Center, Mie, Japan ; Department of Bioinformatics, Mie University Life Science Research Center, Mie, Japan ; Department of Omics Medicine, Mie University Industrial Technology Innovation, Mie, Japan.
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Shimada
authors.affiliation: Central Research Institute, Maruha Nichiro Corporation, Ibaraki, Japan.
authors.forename: Shisei
authors.initials: S
authors.lastname: Kuninaga
authors.affiliation: Department of Molecular and Cellular Pharmacology, Pharmacogenomics and Pharmacoinformatics, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Ariyoshi
authors.affiliation: Department of Molecular and Cellular Pharmacology, Pharmacogenomics and Pharmacoinformatics, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie Japan.
authors.forename: Beibei
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Central Research Institute, Maruha Nichiro Corporation, Ibaraki, Japan.
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Shiina
authors.affiliation: Central Research Institute, Maruha Nichiro Corporation, Ibaraki, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Takahashi
authors.affiliation: Department of Molecular and Cellular Pharmacology, Pharmacogenomics and Pharmacoinformatics, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie Japan ; Department of Systems Pharmacology, Mie University Graduate School of Medicine, Mie, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Umemoto
authors.affiliation: Department of Molecular and Cellular Pharmacology, Pharmacogenomics and Pharmacoinformatics, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie Japan ; Department of Systems Pharmacology, Mie University Graduate School of Medicine, Mie, Japan ; Mie University Medical Zebrafish Research Center, Mie, Japan ; Department of Bioinformatics, Mie University Life Science Research Center, Mie, Japan ; Department of Omics Medicine, Mie University Industrial Technology Innovation, Mie, Japan.
authors.forename: Yuhei
authors.initials: Y
authors.lastname: Nishimura
authors.affiliation: Central Research Institute, Maruha Nichiro Corporation, Ibaraki, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Enari
authors.affiliation: Department of Molecular and Cellular Pharmacology, Pharmacogenomics and Pharmacoinformatics, Mie University Graduate School of Medicine, 2-174, Edobashi, Tsu, Mie Japan ; Department of Systems Pharmacology, Mie University Graduate School of Medicine, Mie, Japan ; Mie University Medical Zebrafish Research Center, Mie, Japan ; Department of Bioinformatics, Mie University Life Science Research Center, Mie, Japan ; Department of Omics Medicine, Mie University Industrial Technology Innovation, Mie, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Tanaka
keywords: Cross-species analysis; DNA microarray; Fatty liver; High-fat feeding; Obesity; Two-dimensional electrophoresis; Zebrafish