title: The biological significance of non-enzymatic reaction of menadione with plasma thiols: enhancement of menadione-induced cytotoxicity to platelets by the presence of blood plasma.
abstract: To test the hypothesis that the non-enzymatic reaction of quinones with thiols in plasma can generate reactive oxygens (ROS), thereby leading to potentiated cellular toxicity, we have studied the effect of a representative quinone compound, menadione, on plasma isolated from rats. The experimental results are as follows: (1) menadione generated ROS via non-enzymatic reaction with protein thiols in plasma; (2) the presence of plasma increased menadione-induced cytotoxicity to platelets; (3) pretreatment of plasma with a thiol-depleting agent significantly suppressed menadione-induced ROS and cytotoxicity. These results suggest that the non-enzymatic reaction of menadione with plasma thiols could be an important process in quinone-induced cellular toxicity.
authors.affiliation: College of Pharmacy, Seoul National University, South Korea.
authors.forename: S H
authors.initials: SH
authors.lastname: Chung
authors.forename: S M
authors.initials: SM
authors.lastname: Chung
authors.forename: J Y
authors.initials: JY
authors.lastname: Lee
authors.forename: S R
authors.initials: SR
authors.lastname: Kim
authors.forename: K S
authors.initials: KS
authors.lastname: Park
authors.forename: J H
authors.initials: JH
authors.lastname: Chung
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D006801:Humans; D010949:Plasma; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000097:blood / Q000378:metabolism*; D014812:Vitamin K / Q000378:metabolism* / Q000633:toxicity
chemical_list: D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds; D014812:Vitamin K