title: Protective effects of natsumikan (Citrus natsudaidai) extract on acetaminophen-induced lethal hepatotoxicity in mice.
abstract: BACKGROUND
  Like other citrus fruits, natsumikan (Citrus natsudaidai) contains several antioxidative nutrients which occur in higher concentrations in the peel than in the pulp. A high dose of acetaminophen (APAP) generates highly reactive intermediates and causes fatal liver injury. In this study, we examined whether an extract from immature natsumikan peel prevents lethal hepatotoxicity induced by a lethal dose of APAP in mice.
  
  
  METHODS
  Male ICR mice were treated orally with natsumikan extract (300 and 1,000 mg/kg) 2, 26, and 50 h before single oral APAP (300 mg/kg) administration. Mice were fasted for 18 h before APAP treatment, but given tap water ad libitum. Survival was assessed for 24 h after APAP treatment.
  
  
  RESULTS
  Following administration of 300 mg/kg APAP, all mice died within 6 h. However, pretreatment with natsumikan extract (300 and 1,000 mg/kg) or silymarin (300 and 1,000 mg/kg) increased the survival rate to 16.7%, 33.3%, 16.7%, and 50%, respectively, at 24 h.
  
  
  CONCLUSIONS
  The results suggest that natsumikan has a protective effect on APAP-induced lethal hepatotoxicity.
authors.affiliation: Department of Geriatric Pharmacology and Therapeutics, Graduate School of Pharmaceutical Sciences, Chiba University, Japan.
authors.forename: Katsunori
authors.initials: K
authors.lastname: Yamaura
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Nakayama
authors.forename: Maki
authors.initials: M
authors.lastname: Shimada
authors.forename: Koichi
authors.initials: K
authors.lastname: Ueno