Characterization of the random positioning machine as a microgravity simulator for biological applications.

Area of Science:

• Biotechnology
• Space Biology
• Cellular Biology

Background:

• Ground-based simulated microgravity platforms are crucial for studying gravitational effects on biological systems.
• Quantitative evaluations of Random Positioning Machines (RPM), a common simulator, are limited.
• Understanding RPM mechanical and biological performance is essential for reliable research.

Purpose of the Study:

• To comprehensively characterize the mechanical and biological performance of an RPM device.
• To evaluate RPM function in randomized, unidirectional, and single-axis clinostat modes.
• To establish a quantitative framework for assessing and optimizing microgravity simulations.

Main Methods:

• Experimental recording of angular velocity profiles using magneto-inertial measurement units.
• Computational modeling to simulate gravity vector dispersion and centrifugal acceleration.
• Exposure of SH-SY5Y neuronal cells to simulated microgravity across different RPM modes.

Main Results:

• All RPM modes effectively simulated microgravity (10-2 to 10-3 g) with low centrifugal acceleration (<0.08 g).
• SH-SY5Y cells showed reduced confluency and increased α-synuclein inclusions in all simulated microgravity conditions.
• Clinostat mode exhibited milder cellular effects compared to other RPM configurations.

Conclusions:

• RPM and clinostat modes can reproduce key features of microgravity, influencing biological responses.
• The study provides a validated computational model for predicting and optimizing microgravity simulations.
• Findings support the use of RPM devices while emphasizing the impact of motion characteristics on cellular outcomes.