title: Pushing the science forward: chitosan nanoparticles and functional repair of CNS tissue after spinal cord injury.
abstract: BACKGROUND
  We continue our exploration of the large polysaccharide polymer Chitosan as an acute therapy for severe damage to the nervous system. We tested the action of subcutaneously injected nanoparticles (~ 100 - 200 nanometers in diameter; 1 mg per ml) against control injections (silica particle of the same size and concentration) in a standardized in vivo spinal cord injury model. These functional tests used standardized physiological measurements of evoked potentials arriving at the sensorimotor cortex subsequent to stimulation of the tibial nerve of the contralateral hindlimb. We further explored the degree of acetylation and molecular weight of chitosan on the success of sealing cell damage using specific probes of membrane integrity.
  
  
  RESULTS
  Not one of the control group showed restored conduction of evoked potentials stimulated from the tibial nerve of the hindleg - through the lesion - and recorded at the sensorimotor cortex of the brain. Investigation if the degree of acetylation and molecular weight impacted "membrane sealing" properties of Chitosan were unsuccessful. Dye - exchange membrane probes failed to show a difference between the comparators in the function of Chitosan in ex vivo injured spinal cord tests.
  
  
  CONCLUSIONS
  We found that Chitosan nanoparticles effectively restore nerve impulse transmission through the crushed adult guinea pig spinal cord in vivo after severe crush/compression injury. The tests of the molecular weight (MW) and degree of acetylation did not produce any improvement in Chitosan's membrane sealing properties.
authors.affiliation: Center for Paralysis Research, Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West, Lafayette, IN 47907, USA.
authors.forename: Bojun
authors.initials: B
authors.lastname: Chen
authors.affiliation: Center for Paralysis Research, Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West, Lafayette, IN 47907, USA.
authors.forename: Debra
authors.initials: D
authors.lastname: Bohnert
authors.affiliation: Center for Paralysis Research, Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West, Lafayette, IN 47907, USA.|Weldon School of Biomedical Engineering, Purdue University, West, Lafayette, IN 47907, USA.
authors.forename: Richard Ben
authors.initials: RB
authors.lastname: Borgens
authors.affiliation: Center for Paralysis Research, Department of Basic Medical Sciences, College of Veterinary Medicine, Purdue University, West, Lafayette, IN 47907, USA.|Present address: New Experimental Therapeutics Branch, National Cancer Center, 809 Madu-1dong, Ilsandong-gu, Goyang-si, Gyeonggi-do, 410-769, Korea.
authors.forename: Youngnam
authors.initials: Y
authors.lastname: Cho