The effects of supplemented sericin on in vitro maturation and preimplantation development of mouse embryos: An experimental study
Background: Mouse embryo culture condition is an essential part of transgenic, reproductive and developmental biology laboratories. Mouse embryonic culture media may have a high risk of serum contamination with pathogens.
Objective: To investigate the effect of sericin as an embryo culture medium supplement on in vitro maturation (IVM), in vitro fertilization (IVF), and development of the preimplantation embryo in mice.
Materials and Methods: The effects of sericin at three concentrations (subgroups) of 0.1%, 0.5%, and 1% as a medium supplement on IVM, IVF, and in vitro development of mouse embryos were separately investigated and compared with a sericin-free (control) group. The cumulative effect of the three concentrations was evaluated for IVM + in vitro development and IVF + in vitro development as follow-up groups.
Results: In the IVM group, compared to the control group, the number of oocysts reaching the MII stage was significantly higher when 1% sericin was used (161/208 = 77.4%). No significant results were observed in the IVF and in vitro development groups with different concentrations of sericin compared to the control group. Among the follow-up groups, in the IVM + in vitro development group, the number of oocytes was higher after passing the IVM and IVF and reaching the blastocysts stage when 1% sericin was used, compared with other sericin subgroups. A significant difference was also noted when compared with the control group (p = 0.048). The IVF + in vitro development study group, on the other hand, did not show any significant relationship.
Conclusion: It can be concluded that 1% sericin can be used as a supplement in mouse embryo cultures to improve the IVM rate. Also, based on the findings, sericin appears to be an effective supplement which can have a positive effect on the development of embryos derived from IVM.
Key words: Sericin, In vitro maturation, In vitro fertilization, Preimplantation embryo, Culture medium, Mice.
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