Ovarian stimulation reduces IL-6 release from mouse and human pre-implantation embryos.

Problem In our previous study, ovarian stimulation retarded post-implantation development and caused 92 genes, including interleukin-6 (IL-6), to be differentially expressed in mouse blastocysts. None of them had been tested at protein level, In this study, we confirm the level change of IL-6 mRNA in mouse blastocysts and IL-6 protein release to the culture medium from mouse and human pre-implantation embryos. Method of study IL-6 mRNA were measured by PCR and IL-6 release to the culture medium were measured by ELISA. Results Superovulation caused a 1.95-fold reduction in IL-6 mRNA in mouse blastocysts and reduced IL-6 secretion into the culture medium in mouse zygotes which were developed to the blastocyst stage (6.397 ± 0.635 versus 4.799 ± 0.312 pg/mL). Ovarian stimulation also significantly reduced IL-6 release into the culture medium in human zygotes which were cultured for 2 days (4.713 ± 0.945 versus 4.543 ± 0.796 pg/mL). Conclusion Our findings indicate that IL-6 might serve as a candidate marker for evaluating embryo developmental competence.