The Effects of Microgravity on the Structure and Function of Cardiomyocytes

Area of Science:

• Cardiovascular Physiology
• Space Biology
• Cellular Biology

Background:

• Spaceflight and microgravity induce significant cardiovascular changes impacting cardiac structure and function.
• Understanding these effects is crucial for astronaut health and in-space tissue engineering.
• Cardiomyocytes are central to cardiac function and are directly affected by microgravity.

Purpose of the Study:

• To review and analyze over 30 years of research on microgravity's impact on cardiomyocytes.
• To identify consistent findings and model-dependent outcomes in microgravity research.
• To synthesize knowledge on cellular and molecular changes in cardiomyocytes due to spaceflight.

Main Methods:

• Comprehensive literature search across five databases.
• Analysis of 62 eligible studies on cardiac cells under real or simulated microgravity.
• Compilation and synthesis of data regarding cardiomyocyte responses to microgravity.

Main Results:

• Consistent alterations reported in Ca2+ handling, metabolism, contractility, and gene expression.
• Three-dimensional human-induced pluripotent stem cell-derived cardiomyocyte (HiPSC-CM) models showed enhanced maturation and proliferation.
• Two-dimensional models predominantly exhibited stress-related dysfunction; in vivo models confirmed structural and functional cardiac remodeling.

Conclusions:

• Microgravity exposure consistently induces cellular and molecular cardiac changes.
• The choice of cardiac model, microgravity platform, and exposure duration critically influence research outcomes.
• Further research using advanced models like HiPSC-CMs is needed to understand and mitigate microgravity's effects on the heart.