title: PSK, a biological response modifier, modifies p53 expression, mitosis and apoptosis in X-ray irradiated mouse embryos: possible cellular mechanism of the anti-teratogenic effect.
abstract: We previously showed that PSK, a biological response modifier, suppressed X-ray irradiation induced ocular anomalies in mouse embryos. In the present study, in mouse embryos irradiated at E7.5, PSK, when administered immediately after irradiation, suppressed mitosis and increased apoptosis as compared with embryos not treated with PSK at 12 hrs after irradiation. In the irradiated embryos, p53, which is normally expressed at a high level in early embryos, increased at 6 hrs and decreased at 12 hrs after irradiation. In the irradiated and PSK-treated embryos, the p53 level did not change at 6 hrs, increased at 12 hrs and decreased at 24 hrs after irradiation. This timing of PSK-induced delayed increase of p53 coincided with that of the PSK-induced decrease in mitosis and increase in apoptosis. These results suggested that PSK modified the p53 level and affected cell proliferation and apoptosis, which might contribute to the suppression of teratogenesis.
authors.affiliation: Department of Anatomy, Shimane Medical University, Izumo 693-8501, Japan.
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Kagohashi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Naora
authors.forename: Hiroki
authors.initials: H
authors.lastname: Otani
mesh_terms: D000818:Animals; D017209:Apoptosis; D002453:Cell Cycle; D002455:Cell Division; D004622:Embryo, Mammalian / Q000528:radiation effects*; D015151:Immunoblotting; D007155:Immunologic Factors / Q000502:physiology*; D051379:Mice; D008813:Mice, Inbred ICR; D008938:Mitosis; D011509:Proteoglycans / Q000502:physiology*; D013723:Teratogens / Q000494:pharmacology; D013997:Time Factors; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*; D014965:X-Rays
chemical_list: D007155:Immunologic Factors; D011509:Proteoglycans; D013723:Teratogens; D016159:Tumor Suppressor Protein p53; C010770:polysaccharide-K