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Piezoelectric Substrates Promote Neurite Growth in Rat Spinal Cord Neurons

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Abstract

We tested the possibility that exogenous electrical activity from a piezoelectric substrate could influence neuronal structure in cultured spinal cord neurons. Oscillating electrical fields were delivered to rat neurons via substrates consisting of poly(vinylidene fluoride) film, both in its piezoelectric (PZ) and non-piezoelectric (PV) forms. To induce oscillating electrical fields at the film surfaces, a 50 Hz mechanical vibration was applied. After 4 days of mechano-electrical stimulation, neuronal densities were increased by 115% and neurons grew 79% more neurites, with more than double the branch points, compared with neurons grown on non-stimulated PZ films (p < 0.001). The effects were due to electrical field, because vibration applied to non-PZ films did not increase neurite growth. We conclude that the oscillating electric fields produced from PZ polymer substrates can induce plastic changes in neurons of the central nervous system and herein we show its influence on neurite growth and branching.

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Abbreviations

ASTM:

American society for testing and materials

CNS:

Central nervous system

DIV:

Days in vitro

EF(s):

Electric field(s)

PDL:

Poly-d-Lysine

PDMS:

Polydimethylsiloxane

PP:

Polypyrrole

PVDF:

Poly(vinylidene fluoride)

PZ:

Piezoelectric

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Acknowledgments

We thank Dr. Nadarajah Vasanthan for chemical analyses, Dr. Jennifer Lynch for assistance, and Rocío Naveiras Cabello for image analysis. The NJ Commission on Spinal Cord Research provided the Fellowship 07-2932-SCR-E-0 to N.R., the NSF-IGERT Fellowship DGE 033196 was provided to M.W., and NSF grants IBN-0919747 and IBN-0548543, March of Dimes Foundation Grants 1-FY04- 107, and NJCSCR grant # 07-3070-SCR-E-0 to B.L.F.

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Authors and Affiliations

  1. Department of Biomedical Engineering, Rutgers University, 599 Taylor Rd, Piscataway, NJ, 08854, USA

    Núria Royo-Gascon & William Craelius

  2. VA Cooperative Studies Program Coordinating Center, VA Connecticut Healthcare System, 950 Campbell Avenue, West Haven, CT, 06516, USA

    Michael Wininger

  3. Department of Chemical and Biochemical Engineering, Rutgers University, 98 Brett Rd, Piscataway, NJ, 08854, USA

    Jerry I. Scheinbeim

  4. Department of Cell Biology and Neuroscience, Rutgers University, 604 Allison Rd, Piscataway, NJ, 08854, USA

    Bonnie L. Firestein

  5. Prosthetics and Orthotics Program, University of Hartford, 200 Bloomfield Ave, West Hartford, CT, 06117, USA

    Michael Wininger

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  1. Núria Royo-Gascon
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Correspondence to Núria Royo-Gascon.

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Associate Editor Scott I. Simon oversaw the review of this article.

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Royo-Gascon, N., Wininger, M., Scheinbeim, J.I. et al. Piezoelectric Substrates Promote Neurite Growth in Rat Spinal Cord Neurons. Ann Biomed Eng 41, 112–122 (2013). https://doi.org/10.1007/s10439-012-0628-y

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