title: Inhibition of cyclophoshamide-induced mutagenicity by microsized powder of selenium-enriched green tea in mice.
abstract: Previously, the antioxidant activity of Se-enriched green tea extracts has been studied in vitro. In the present study, an in vivo micronuclei test was employed to assess the antimutagenic effect of microsized Se-enriched green tea powder (MSTP) in mice bone marrow. Pretreatments of MSTP, micrometer-sized regular tea powder (MRTP), selenite, and MRTP + selenite were given by gavage for 29 consecutive days prior to cyclophoshamide (CP) treatment. Certain key antioxidant enzymes were also investigated to elucidate the mechanism of antimutagenic effect. Results indicated that MSTP and MRTP or selenite alone did not significantly induce micronuclei at either concentration, confirming its nonmutagenicity. In the CP-treated groups, significant suppressions in the micronuclei were recorded following pretreatment with MSTP, MRTP, and selenite administration. The antimutagenic effect of MSTP was evidently observed by significant reduction in the frequencies of micronuclei in bone marrow cells when compared to a positive control group. The administration of MSTP, selenite, and MRTP + selenite also increased the levels of selenium concentration, glutathione peroxidase (GPx), and superoxide dismutase (SOD) enzymes in both blood and liver. However, no pronounced differences in activities of GPx and SOD were found among MSTP, selenite, and MRTP + selenite. The present findings demonstrate that the antimutagenic potential of MSTP could not be solely related to the enhancment of antioxidant enzymes of GPx and SOD.
authors.affiliation: College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, Institute of Supervision and Inspection on Product Quality, Lianyungang Bureau of Quality and Technical Supervision, Lianyungang 222000, People's Republic of China.
authors.forename: Juan
authors.initials: J
authors.lastname: Xu
authors.forename: Jing
authors.initials: J
authors.lastname: Zhou
authors.forename: Jianchun
authors.initials: J
authors.lastname: Sheng
authors.forename: Yong
authors.initials: Y
authors.lastname: Fang
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Guiju
authors.initials: G
authors.lastname: Sun
authors.forename: Qiuhui
authors.initials: Q
authors.lastname: Hu
mesh_terms: D000818:Animals; D016587:Antimutagenic Agents / Q000008:administration & dosage*; D001854:Bone Marrow Cells / Q000187:drug effects / Q000648:ultrastructure; D003520:Cyclophosphamide / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D005519:Food Preservation; D005979:Glutathione Peroxidase / Q000032:analysis / Q000097:blood; D008099:Liver / Q000737:chemistry; D051379:Mice; D048629:Micronuclei, Chromosome-Defective / Q000187:drug effects; D010316:Particle Size; D012643:Selenium / Q000008:administration & dosage* / Q000032:analysis / Q000097:blood; D018038:Sodium Selenite / Q000008:administration & dosage; D013482:Superoxide Dismutase / Q000032:analysis / Q000097:blood; D013662:Tea / Q000737:chemistry*
chemical_list: D016587:Antimutagenic Agents; D013662:Tea; D003520:Cyclophosphamide; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D012643:Selenium; D018038:Sodium Selenite