title: Protection of tea melanin on hydrazine-induced liver injury.
abstract: The protective activity of melanin derived from tea (MDFT) was studied using hydrazine as a DNA-reactive chemical agent. Intra-peritoneal administration of MDFT at the doses of 5 or 20 mg/kg dose-dependently prevented liver toxicity induced by hydrazine in rats. It normalized rises in serum alanine transferase activity and a decrease in the glutathione level in the liver. It also reduced the hepatic malondialdehyde concentration. Monitoring the intensity of chemiluminescence showed that MDFT could prevent the production of free radicals that are generated owing to metabolic transformation of hydrazine. It also prevented the formation 8-hydroxy-deoxyguanosine (8-OH-dG) DNA adducts. The results obtained in vivo and in vitro suggest that MDFT confers marked protection of the liver against hydrazine-induced oxidative toxicity.
authors.affiliation: Section of Gynecologic Oncology, Department of Obstetrics and Gynecology, China Medical College, 91 Hsueh Shih Road, Taichung 404, Taiwan, ROC.
authors.forename: Y C
authors.initials: YC
authors.lastname: Hung
authors.forename: V M
authors.initials: VM
authors.lastname: Sava
authors.forename: V A
authors.initials: VA
authors.lastname: Blagodarsky
authors.forename: M-Y
authors.initials: MY
authors.lastname: Hong
authors.forename: G S
authors.initials: GS
authors.lastname: Huang
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D000975:Antioxidants / Q000008:administration & dosage / Q000302:isolation & purification / Q000627:therapeutic use*; D056486:Chemical and Drug Induced Liver Injury / Q000097:blood / Q000473:pathology / Q000517:prevention & control*; D018736:DNA Adducts / Q000187:drug effects; D004249:DNA Damage; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005609:Free Radicals / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D006834:Hydrazines / Q000633:toxicity; D007274:Injections, Intraperitoneal; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008543:Melanins / Q000008:administration & dosage / Q000302:isolation & purification / Q000627:therapeutic use*; D010936:Plant Extracts / Q000008:administration & dosage / Q000302:isolation & purification / Q000627:therapeutic use*; D051381:Rats; D017208:Rats, Wistar; D013662:Tea / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D018736:DNA Adducts; D005609:Free Radicals; D006834:Hydrazines; D008543:Melanins; D010936:Plant Extracts; D013662:Tea; C029424:hydrazine; D008315:Malondialdehyde; D000080242:8-Hydroxy-2'-Deoxyguanosine; D000410:Alanine Transaminase; D003849:Deoxyguanosine; D005978:Glutathione