Smartphone generated electrical fields induce axon regrowth within microchannels following injury

Area of Science:

• Neuroscience
• Biomedical Engineering
• Regenerative Medicine

Background:

• Axonal injury is a primary cause of central nervous system damage, leading to functional deficits.
• Electrical stimulation has shown potential for axon sprouting in vitro, but its efficacy in stretch-induced axonal injury models was unexplored.

Purpose of the Study:

• To investigate the effect of electrical fields on the morphological changes of ruptured axons using an electrostimulation-on-a-chip system.
• To assess the potential of electrical stimulation for promoting axon regrowth following stretch-induced axonal injury.

Main Methods:

• Development of a simple electrostimulation-on-a-chip device.
• Utilizing a smartphone pulse generator to deliver electrical stimulation in microchannels via sterile needles.
• Culturing and observing stretch-injured axons in microchannels with and without electrical stimulation.

Main Results:

• Electrical stimulation promoted axon outgrowth in 72% of injured axons within microchannels.
• Regenerated axons exhibited a growth rate of 46 µm/day.
• Unstimulated control axons showed 100% degeneration within 3 days, with no regrowth observed within 9 days.

Conclusions:

• Electrical stimulation effectively promotes axon regrowth after stretch-induced injury in a microchannel culture system.
• The findings support an engineering approach combining soft microchannel scaffolds with stimulating electrodes.
• This research encourages the development of potential medical devices for traumatic brain and spinal cord injuries.