title: Hemizygosity of transsulfuration genes confers increased vulnerability against acetaminophen-induced hepatotoxicity in mice.
abstract: The key mechanism for acetaminophen hepatotoxicity is cytochrome P450 (CYP)-dependent formation of N-acetyl-p-benzoquinone imine, a potent electrophile that forms protein adducts. Previous studies revealed the fundamental role of glutathione, which binds to and detoxifies N-acetyl-p-benzoquinone imine. Glutathione is synthesized from cysteine in the liver, and N-acetylcysteine is used as a sole antidote for acetaminophen poisoning. Here, we evaluated the potential roles of transsulfuration enzymes essential for cysteine biosynthesis, cystathionine β-synthase (CBS) and cystathionine γ-lyase (CTH), in acetaminophen hepatotoxicity using hemizygous (Cbs(+/-) or Cth(+/-)) and homozygous (Cth(-/-)) knockout mice. At 4 h after intraperitoneal acetaminophen injection, serum alanine aminotransferase levels were highly elevated in Cth(-/-) mice at 150 mg/kg dose, and also in Cbs(+/-) or Cth(+/-) mice at 250 mg/kg dose, which was associated with characteristic centrilobular hepatocyte oncosis. Hepatic glutathione was depleted while serum malondialdehyde accumulated in acetaminophen-injected Cth(-/-) mice but not wild-type mice, although glutamate-cysteine ligase (composed of catalytic [GCLC] and modifier [GCLM] subunits) became more activated in the livers of Cth(-/-) mice with lower Km values for Cys and Glu. Proteome analysis using fluorescent two-dimensional difference gel electrophoresis revealed 47 differentially expressed proteins after injection of 150 mg acetaminophen/kg into Cth(-/-) mice; the profiles were similar to 1000 mg acetaminophen/kg-treated wild-type mice. The prevalence of Cbs or Cth hemizygosity is estimated to be 1:200-300 population; therefore, the deletion or polymorphism of either transsulfuration gene may underlie idiosyncratic acetaminophen vulnerability along with the differences in Cyp, Gclc, and Gclm gene activities.
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Hagiya
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Shotaro
authors.initials: S
authors.lastname: Kamata
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Saya
authors.initials: S
authors.lastname: Mitsuoka
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Norihiko
authors.initials: N
authors.lastname: Okada
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Saori
authors.initials: S
authors.lastname: Yoshida
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Junya
authors.initials: J
authors.lastname: Yamamoto
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Rika
authors.initials: R
authors.lastname: Ohkubo
authors.affiliation: Environmental Biology Laboratory, School of Medicine, University of Tsukuba, Ibaraki 305-8575, Japan.
authors.forename: Yumi
authors.initials: Y
authors.lastname: Abiko
authors.affiliation: Jobu Hospital for Respiratory Diseases, Maebashi 371-0048, Japan.
authors.forename: Hidenori
authors.initials: H
authors.lastname: Yamada
authors.affiliation: Department of Immunology, Akita University Graduate School of Medicine, Akita 010-8543, Japan.
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Akahoshi
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Kasahara
authors.affiliation: Environmental Biology Laboratory, School of Medicine, University of Tsukuba, Ibaraki 305-8575, Japan.
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Kumagai
authors.affiliation: Department of Biochemistry, Keio University School of Pharmaceutical Sciences, Tokyo 105-8512, Japan. Electronic address: isao-ishii@umin.ac.jp.
authors.forename: Isao
authors.initials: I
authors.lastname: Ishii
mesh_terms: D000082:Acetaminophen / Q000633:toxicity*; D018712:Analgesics, Non-Narcotic / Q000633:toxicity*; D000818:Animals; D056486:Chemical and Drug Induced Liver Injury / Q000235:genetics* / Q000473:pathology / Q000517:prevention & control*; D003541:Cystathionine beta-Synthase / Q000235:genetics; D003542:Cystathionine gamma-Lyase / Q000235:genetics; D005260:Female; D005978:Glutathione / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation / Q000235:genetics / Q000502:physiology; D013431:Sulfates / Q000378:metabolism*; D015053:Zygote / Q000187:drug effects*
chemical_list: D018712:Analgesics, Non-Narcotic; D013431:Sulfates; D000082:Acetaminophen; D003541:Cystathionine beta-Synthase; D003542:Cystathionine gamma-Lyase; D005978:Glutathione
keywords: 2D DIGE; Cystathionine β-synthase; Cystathionine γ-lyase; Glutamate–cysteine ligase; MALDI-TOF/MS; Oncosis