Mechanical activities of self-beating cardiomyocyte aggregates under mechanical compression

Area of Science:

• Cardiovascular Research
• Biophysics
• Cellular Mechanics

Background:

• Electrical communication is the primary focus in cardiomyocyte (CM) research.
• Emerging evidence suggests mechanical communication plays a role in CM function.
• Cardiac spheroids (CSs) offer a model for studying multicellular CM behavior.

Purpose of the Study:

• To investigate mechanical communication in cardiac spheroids (CSs).
• To determine the effect of mechanical compression on CS beating.
• To elucidate the contribution of cell stress to mechanical work in CSs.

Main Methods:

• Compression of single and paired cardiac spheroids (CSs) between parallel plates.
• Measurement of beating frequency and mechanical energy.
• Application of contact mechanics to analyze stress-strain relationships.

Main Results:

• Mechanical compression significantly increased beating frequency and energy in single CSs.
• A scaling law demonstrated that stressed cells drive mechanical work in compressed CSs.
• Compression induced synchronous beating and mechanical coupling in paired CSs, enhancing stability.

Conclusions:

• Cardiac spheroids (CSs) exhibit cooperative mechanical communication under compression.
• Mechanical compression is a critical parameter for evaluating cardiomyocyte (CM) aggregate activity.
• Findings suggest mechanical forces are integral to CM network function.