The metabolism of cholesterol after bile duct degeneration in lamprey

2012 Fiscal Year Final Research Report

• Project/Area Number: 23792026
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Pediatric surgery
• Research Institution: Akita University
• Principal Investigator: MAYAKO Morii 秋田大学, 医学部, 助教 (10375280)
• Project Period (FY): 2011 – 2012
• Keywords: ヤツメウナギ / 胆汁酸 / 肝線維化 / コレステロール代謝

Research Abstract

Lampreys are unique vertebrates in that they lose biliary trees entirely during the metamorphosis. Despite the biliary atresia, lampreys do not develop either biliary cirrhosis or liver dysfunction. In other vertebrates, obstruction of bile ducts results in fatality because of the cytotoxicity of bile salts. It means that lampreys have evolved to use another metabolic pathway of bile juice in order to avoid the cholestasis. However, molecular mechanism of this pathway is still unknown. The aim of this study is to investigate the way how the lamprey avoids the pathological consequence of cholestasis. We have cloned the cDNA sequences of two kinds of P450, which show high degree of homology with mammalian CYP7A1 and CYP27A1, respectively. We are now evaluating the expression levels of the mRNA for these genes in liver, gonad, gill, heart and intestine along with the temporal expression profiles from larva to adult. The present study suggests how and where bile acids are detoxified in adult lampreys. Understanding how lampreys avoid cholestasis could be valuable for progress in the treatment of human obstructive cholangiopathy.

Research Products

• [Journal Article] Characterization of a cellular retinol-binding protein from lamprey (2012)
  • Author(s): Mezaki Y, Morii M, Yoshikawa K, Yamaguchi N, Miura M, Imai K, Yoshino H, Senoo H.
  • Journal Title: Lethenteron japonicum. Comp. Biochem. Physiol. B Biochem. Mol. Biol. Volume: 161(3) Pages: 233-239
• [Presentation] ヤツメウナギにおける胆汁排泄機構 (2013)
  • Author(s): 森井真也子、目崎喜弘、吉川究、山口典子、三浦光隆、今井克幸、蛇口琢、渡部亮、妹尾春樹、吉野祐顕
  • Organizer: 第118回日本解剖学会
  • Place of Presentation: 香川
  • Year and Date: 2013-03-30
• [Presentation] The metabolism of cholesterol after bile duct degeneration in lamprey (2012)
  • Author(s): 森 井真也子、目崎喜弘、吉川究、山口典子、三浦光隆、今井克幸、蛇口琢、渡部亮、妹尾春樹、吉野祐顕
  • Organizer: 第117回日本解剖学会
  • Place of Presentation: 山梨
  • Year and Date: 2012-03-28
• [Presentation] Reversibility of periductal fibrosis during biliary atresia in the lamprey (2011)
  • Author(s): ayako Morii, Yoshihiro Mezaki, Noriko Yamaguchi, Kiwamu Yoshikawa, Mitsutaka Miura, Katsuyuki Imai, Taku Hebiguchi, Ryo Watanabe, Hiroaki Yoshino, and Haruki Senoo
  • Organizer: 16th ISHSR International Meeting
  • Place of Presentation: Italy
  • Year and Date: 2011-09-23
• [Book] How do lampreys avoid cholestasis after bile duct degeneration (2011)
  • Author(s): Morii M, Mezaki Y, Yoshikawa K, Miura M, Imai K, Hebuguchi T, Watanabe R, Asanuma Y, Yoshino H, and Senoo H.
  • Total Pages: 81-98
  • Publisher: Cholestasis. ed. Tripodi V. INTECH, Rijeka, Croatia