Mechanical and Functional Responses in Astrocytes under Alternating Deformation Modes Using Magneto-Active Substrates

Area of Science:

• Mechanobiology
• Cellular mechanics
• Biomaterials

Background:

• Cellular responses to mechanical cues are critical in development and disease.
• Understanding cell mechanics under dynamic substrate deformation is challenging.
• Existing methods lack flexibility in applying controlled mechanical stimuli.

Purpose of the Study:

• Introduce NeoMag, a novel system for cell mechanics assays using magneto-active materials.
• Investigate the impact of substrate deformation on astrocyte mechanical properties and function.
• Explore the role of mechanical cues in simulating conditions like traumatic brain injury and stroke.

Main Methods:

• Utilized NeoMag system with multidomain magneto-active materials for substrate actuation.
• Performed mechanobiology assays on 2D and 3D astrocyte cultures.
• Integrated NeoMag with nanoindenters for precise mechanical property evaluation.
• Studied cellular responses under various substrate deformation modes (sustained, dynamic).

Main Results:

• NeoMag enabled flexible, reversible substrate deformation for cell mechanics studies.
• Astrocyte stiffness exhibited heterogeneous changes (>50%) based on substrate strain orientation.
• Substrate deformation significantly altered astrocyte calcium dynamics.
• Sustained deformation led to actin reorganization, Piezo1 activation, and altered calcium signaling.
• Dynamic deformation caused transient Piezo1 activation, actin disruption, and long-term cell softening.

Conclusions:

• NeoMag system effectively delivers controlled mechanical cues to cells for mechanobiology research.
• Substrate deformation induces significant, orientation-dependent mechanical and functional alterations in astrocytes.
• Findings provide insights into astrocyte behavior under simulated neurological injury conditions.
• The technology offers new avenues for studying cell mechanics and mechanotransduction.