title: Clinical evaluation of ezetimibe on bile lithogenicity in humans: Use of transnasal endoscopy for bile sampling.
abstract: OBJECTIVE
  Ezetimibe inhibits cholesterol absorption by blocking Niemann-Pick C1-like 1 proteins (NPC1L1) expressed in the small intestine. Because NPC1L1 is also expressed in human liver, ezetimibe conceivably alters biliary lipid compositions. Here, we performed a clinical trial investigating the effect of ezetimibe on biliary lipids using transnasal endoscopy for bile collection.
  
  
  METHODS
  Eight patients with dyslipidemia enrolled in this study completed blood and bile sampling before and at 3 months after ezetimibe treatment (10 mg/day), and the samples are analyzed.
  
  
  RESULTS
  Endoscopic bile sampling was performed safely and painlessly. Serum sterol-based biomarkers declared decreased cholesterol absorption and increased synthesis. On analysis of biliary lipids, four of the eight patients showed relative decrease of cholesterol and increase of bile acids with improved lithogenicity while the remainder exhibited the symmetrical changes.
  
  
  CONCLUSIONS
  Our data suggests that biliary lithogenicity is not worsened by ezetimibe. The regulation of biliary cholesterol is presumably multifactorial such as body cholesterol pool size and biliary cholesterol reabsorption by NPC1L1 in the liver.
authors.affiliation: Department of General Internal Medicine, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Nobusuke
authors.initials: N
authors.lastname: Kishikawa
authors.affiliation: Department of General Internal Medicine, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Keishi
authors.initials: K
authors.lastname: Kanno
authors.affiliation: Department of General Internal Medicine, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Sugiyama
authors.affiliation: Department of General Internal Medicine, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Yokobayashi
authors.affiliation: Department of General Internal Medicine, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Mizooka
authors.affiliation: Department of General Internal Medicine, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Susumu
authors.initials: S
authors.lastname: Tazuma
keywords: bile sampling; biliary lipids; ezetimibe; lithogenicity; transnasal endoscopy