Article abstract


Nature Nanotechnology 5, 80 - 87 (2010)
Published online: 8 November 2009 | doi:10.1038/nnano.2009.303

Subject Category: Nanomedicine

Effective repair of traumatically injured spinal cord by nanoscale block copolymer micelles

Yunzhou Shi1, Sungwon Kim2, Terry B. Huff3, Richard B. Borgens1,4, Kinam Park1,2, Riyi Shi1,4 & Ji-Xin Cheng1,3


Spinal cord injury results in immediate disruption of neuronal membranes, followed by extensive secondary neurodegenerative processes. A key approach for repairing injured spinal cord is to seal the damaged membranes at an early stage. Here, we show that axonal membranes injured by compression can be effectively repaired using self-assembled monomethoxy poly(ethylene glycol)-poly(d,l-lactic acid) di-block copolymer micelles. Injured spinal tissue incubated with micelles (60 nm diameter) showed rapid restoration of compound action potential and reduced calcium influx into axons for micelle concentrations much lower than the concentrations of polyethylene glycol, a known sealing agent for early-stage spinal cord injury. Intravenously injected micelles effectively recovered locomotor function and reduced the volume and inflammatory response of the lesion in injured rats, without any adverse effects. Our results show that copolymer micelles can interrupt the spread of primary spinal cord injury damage with minimal toxicity.

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  1. Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, USA
  2. Department of Industrial and Physical Pharmacy, Purdue University, West Lafayette, Indiana 47907, USA
  3. Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
  4. Department of Basic Medical Sciences, Purdue University, West Lafayette, Indiana 47907, USA

Correspondence to: Ji-Xin Cheng1,3 e-mail: jcheng@purdue.edu