Mouse embryo motion and embryonic development from the 2-cell to blastocyst stage using mechanical vibration systems

Area of Science:

• Developmental Biology
• Biophysics

Background:

• Physical factors significantly influence embryonic development.
• Understanding mechanical stimuli's role is crucial for optimizing in vitro fertilization (IVF) and embryo culture.

Purpose of the Study:

• To investigate the effects of mechanical stimuli, specifically shear stress (SS) and mechanical vibration (MV), on mouse embryonic development from the 2-cell to blastocyst stage.
• To evaluate physical factors affecting embryonic development and compare different mechanical vibration systems (MVSs).

Main Methods:

• Mouse embryos (2-cell to blastocyst stage) were cultured and subjected to mechanical vibration using two distinct mechanical vibration systems (MVSs).
• Shear stress (SS) was quantified by observing embryo movement during mechanical vibration (MV).
• Embryo development was monitored over 3 days, comparing MVS conditions to static culture.

Main Results:

• Mechanical vibration systems (MVSs) did not alter medium motion or diffusion rates compared to static conditions.
• Three days of culture with MVS did not enhance embryonic development.
• MVS transmitted MV power efficiently, causing a significant decrease in development to the morula or blastocyst stage after 2 days.
• Macroscopic diffusion of secreted materials in dynamic culture systems improved mouse embryo development.
• Mouse embryos appear more sensitive to SS and MV at pre-blastocyst stages than at the blastocyst stage.

Conclusions:

• Mechanical vibration and shear stress can negatively impact early mouse embryonic development.
• Mouse embryos exhibit higher sensitivity to physical and chemical stimuli compared to human or pig embryos, potentially due to their thinner zona pellucida.
• Optimizing dynamic culture systems that facilitate macroscopic diffusion is key for improving embryo development.