title: Hepatic triglyceride lipase plays an essential role in changing the lipid metabolism in genotype 1b hepatitis C virus replicon cells and hepatitis C patients.
abstract: OBJECTIVE
  Recently, several studies have shown the existence of associations between lipoprotein profiles and hepatitis C virus (HCV), although only a limited amount of information is available about the mechanisms underlying the changes in the lipoprotein profiles associated with HCV. In this study, we investigated the association between lipoprotein profile, classified according to the particle size, and lipoprotein metabolism.
  
  
  METHODS
  We used four kinds of cells for this experiment; full-length genome HCV RNA replicon cells (OR6), sub-genomic HCV RNA replicon cells (sO), and OR6c cells and sOc cells, which were the same cell lines treated with interferon-α. The triglyceride (TG) levels in the lipoprotein subclasses of the culture medium were measured by high-performance liquid chromatography. The mRNA expression levels of several molecules associated with lipoprotein metabolism were measured in the OR6, OR6c, sO and sOc cells. To confirm some of the results obtained using the in vitro system, liver biopsy samples obtained from the patients were also examined.
  
  
  RESULTS
  The content of TG in the large low-density lipoprotein (LDL) and medium LDL in the culture medium was increased only in the OR6 cells. The hepatic triglyceride lipase (HTGL) mRNA expression levels were lower in the OR6 cells than in the OR6c cells (P < 0.01). Examination of the HTGL expression levels in the patients' livers revealed a decrease in HTGL expression in the chronic hepatitis C liver as compared with that in the chronic hepatitis B or non-alcoholic steatohepatitis liver (P < 0.01).
  
  
  CONCLUSIONS
  We showed that HCV inhibits HTGL production in hepatocytes, inducing a change of the lipoprotein profile.
authors.affiliation: Gastroenterology Division, Yokohama City University Graduate School of Medicine, Yokohama, Japan; Departments of Neuroanatomy, Yokohama City University Graduate School of Medicine, Yokohama, Japan.
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Shinohara
authors.forename: Kento
authors.initials: K
authors.lastname: Imajo
authors.forename: Masato
authors.initials: M
authors.lastname: Yoneda
authors.forename: Wataru
authors.initials: W
authors.lastname: Tomeno
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ogawa
authors.forename: Koji
authors.initials: K
authors.lastname: Fujita
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kirikoshi
authors.forename: Junichiro
authors.initials: J
authors.lastname: Takahashi
authors.forename: Kengo
authors.initials: K
authors.lastname: Funakoshi
authors.forename: Masanori
authors.initials: M
authors.lastname: Ikeda
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kato
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nakajima
authors.forename: Satoru
authors.initials: S
authors.lastname: Saito
keywords: hepatic triglyceride lipase; hepatitis C virus; high-performance liquid chromatography; lipoprotein metabolism; replicon cell