While Mg deficiency results in congenital abnormalities and embryo death, the underlying mechanisms are unknown. The in vitro embryo culture system allows one to study, at a mechanistic level, how defects occur during discrete periods of development. Embryos were removed on gestation day 10 from dams fed either a control (Mg+) or Mg deficient (Mg-) diet (1175 vs. 40 ug Mg/g diet). Embryos were cultured in Mg adequate (1.1 mM) or Mg deficient (0.4 mM) sera for 48h. Embryos from Mg+ dams cultured in Mg+ serum developed normally. In contrast, embryos from Mg- dams cultured in Mg- serum exhibited multiple abnormalities, including enlarged heart, and open or misshapen neural tubes. Mg+ embryos cultured in Mg sera also developed abnormally, albeit not to the same magnitude as Mg- embryos cultured under Mg- conditions. Embryos were stained with Nile Blue Sulfate; cell death patterns were similar between Mg+ and Mg- embryos indicating that apoptosis is not a mechanism underlying Mg deficiency teratogenicity. Histological evaluation of Mg+ embryos cultured in Mg+ serum showed normal morphology. In contrast, Mg-embryos cultured in Mg- serum were characterized by an overgrowth of cells resulting in irregular neuroepithelial thickness and deformation of the neural tube. In addition, cellular debris was seen in the diencephalon and optic vesicle, and blood was present in the pericardium and optic vrsicle. These data show that the embryo culture model can be used to study the mechanisms underlying Mg deficiency-induced teratogenesis.
|Original language||English (US)|
|State||Published - 1997|
ASJC Scopus subject areas
- Agricultural and Biological Sciences (miscellaneous)
- Biochemistry, Genetics and Molecular Biology(all)
- Cell Biology