Studies on ergothioneine. VIII. Preventive effects of ergothioneine on cadmium-induced teratogenesis.

Abstract
Possible preventive effects of ergothioneine on cd-induced teratogenesis were examined. Cd (2 mg/kg) was administered i.p. to mice on day 7 of pregnancy. The treatment group of mice was given i.p. ergothioneine daily at a dose of 80 mg/kg during days 5-9; the control group was given saline solution. These mice were subjected to cesarean section on day 17 of gestation, and the number of dead fetuses, the body weight of living fetuses, and external, skeletal and visceral abnormalities were recorded. 109Cd (50 .mu.Ci/2 mg Cd per kg) was administered i.p. to other pregnant mice on day 7, and the tissue distribution of the Cd was examined on days 8 and 17 of gestation. Administration of ergothioneine alone had no effect on external, skeletal and visceral abnormalities. Of 257 cases, fetuses in 79 cases died or were resorbed after Cd administration. The body weight of living fetuses was significantly reduced, and exencephalia (64%), open eye (31.5%) and marked skeletal malformations of cervical, thoracic and lumbar vertebrae were observed. Ergothioneine very significantly reduced the incidences of exencephalia, open eye and skeletal abnormalities caused by Cd. There were no differences between both groups in the in vivo distribution of 109Cd, or in the form of 109Cd present in the liver, kidney and placenta. Apparently, ergothioneine inhibits cd-induced teratogenesis through a mechanism other than causing changes in the maternal distribution of cd and in Cd transfer to fetuses.