Protective Effect of Icariin on the Development of Preimplantation Mouse Embryos against Hydrogen Peroxide-Induced Oxidative Injury

During in vitro cultivation of preimplantation embryos, the balance between ROS production and clearance is disturbed and may lead to incompetent embryos, which might be a main reason of IVF-ET failure. Icariin (ICA) is reported to be active in clearing ROS. The present study aimed to investigate whether ICA could reverse H(2)O(2) pretreatment-induced mouse preimplantation embryo development arrest and, furthermore, to study the underlying mechanisms by detecting ROS levels, mitochondrial membrane potential (ΔΨm), and zygotic gene expression. The results showed that, after pretreating mouse 1-cell embryos with 40 μM or 60 μM H(2)O(2) for 30 min, the developmental rate of each stage embryos decreased obviously. And by adding 40 μM ICA, the developmental arrest of 60 μM H(2)O(2) pretreated preimplantation embryos was significantly reversed. Immunostaining results showed that, comparing with the control group, ROS levels of H(2)O(2) pretreated 1-cell embryos were elevated and ΔΨm levels decreased. By adding ICA, the ROS levels of H(2)O(2) pretreated 1-cell embryos were decreased and ΔΨm levels were elevated. Furthermore, RT-qPCR results showed that the addition of ICA reversed the H(2)O(2)-induced downregulation of eIF-1A mRNA expression levels. These results indicate that ICA, when used in appropriate concentration, could decrease ROS levels, increase ΔΨm levels, and modulate the expression of zygotic gene activation (ZGA) marker gene eIF-1A, and thus promote the development of H(2)O(2)-pretreated mouse preimplantation embryos.