Quantifying Mechanical Strain–Induced Membrane Damage in Early Neuronal Cells Using an In Vitro Traumatic Brain Injury Model

This protocol describes a reproducible workflow for modeling in vitro impact-induced traumatic brain injury (TBI) using a mechanical stretch system applied to differentiated SH-SY5Y human neuroblastoma cells cultured on polydimethylsiloxane (PDMS) substrates. The protocol integrates three primary components: (1) fabrication and surface modification of deformable PDMS chambers to support cellular adhesion, (2) partial differentiation of SH-SY5Y cells using retinoic acid, and (3) induction of controlled mechanical strain to simulate mild to moderate TBI. The stretch-induced injury model enables quantitative assessment of cellular viability and recovery following mechanical insult. This approach provides a versatile platform for studying cellular and molecular mechanisms of TBI, screening neuroprotective compounds, and exploring mechanobiological responses in neural cells under controlled strain magnitudes and rates. Key features • Provides reproducible in vitro modeling of traumatic brain injury in differentiated SH-SY5Y neurons via controlled mechanical stretch. • Combines PDMS chamber fabrication and polydopamine coating to generate deformable, biocompatible, neuron-adhesive substrates for mechanobiology assays. • Flexible platform for testing neuroprotective compounds and investigating mechanotransduction pathways under physiologically relevant stretch conditions.