Developmental blockage of mouse embryos caused by fatty acids.

PURPOSE

It has been shown that lipid peroxides derived from polyunsaturated fatty acids (PUFAs) inhibit the proliferation of various cells. In the meantime, it has been suggested that oxidative stress is closely related to the developmental blockage of mammalian embryos cultured in vitro. In this study, we investigated the effects by various fatty acids on mouse embryo development in vitro, and the reversal of these effects by various antioxidants such as superoxide dismutase, ascorbic acid, alpha-tocopherol, uric acid, and ethylenediaminetetraacetic acid.

METHODS

Pronuclear and two-cell stage mouse (ICR) embryos were cultured in Biggers-Whitten-Whittingham medium with 0.3% bovine serum albumin alone or complexed with one of the following fatty acids: palmitic, stearic, oleic, linoleic, linolenic, or arachidonic acid. We also measured the fluorescence emission of embryos in media containing various fatty acids in order to investigate the involvement of H2O2 or lipid peroxidation in embryo development.

RESULTS

Palmitic acid and PUFAs including linoleic acid inhibited the embryo development. The inhibitory effect of PUFAs was attenuated by adding antioxidants into the media, while the inhibitory effect of palmitic acid was not. Both pronuclear and two-cell stage embryos with PUFAs showed markedly more intensive emissions than those under other conditions.

CONCLUSIONS

These results suggest that lipid radicals can easily be generated in early stage embryos and that blastomeres are among the cells vulnerable to the damage by lipid peroxidation.