ABSTRACT
Although changes in protein expression in spinal cord injury (SCI) would be of pivotal interest, information so far is limited. It was therefore the aim of the study to determine protein levels and post-translational modifications in the early phase following SCI in the rat. SCI was induced in Sprague-Dawley rats and sham operated rats served as controls. A gel-based proteomic approach using two-dimensional gel electrophoresis followed by quantification with specific software and subsequent identification of differentially expressed proteins by nano-ESI-LC-MS/MS was applied. Proteins of several pathways and cascades were dysregulated in SCI: 14-3-3 epsilon protein, dynein light chain 1, and tubulin beta-5 chain showed higher levels in SCI, whereas adenylyl cyclase associated protein 1, dihydropyrimidinase-related protein 2, F-actin capping protein subunit beta, glyceraldehyde-3-phosphate dehydrogenase, stress-induced phosphoprotein 1 and transthyretin showed lower levels in the injured tissue. Post-translational modifications indicated free oxygen radical attack on proteins in SCI. The occurrence of stress is indicated by deranged stress-induced phosphoprotein 1 and signaling abnormalities are reflected by adenylyl cyclase-associated protein 1 and 14-3-3 epsilon protein. The findings propose the involvement of the corresponding cascades and challenge further work into aberrant signaling and oxidative stress in SCI, which may form the basis for experimental intervention for spinal cord trauma.
Subject(s)
Protein Processing, Post-Translational , Proteins/analysis , Proteomics/methods , Spinal Cord Injuries/metabolism , 14-3-3 Proteins/analysis , 14-3-3 Proteins/metabolism , Animals , Blotting, Western , Cytoskeletal Proteins/analysis , Cytoskeletal Proteins/metabolism , Electrophoresis, Gel, Two-Dimensional , Male , Mass Spectrometry , Phosphorylation , Proteins/metabolism , Rats , Rats, Sprague-Dawley , Tubulin/analysis , Tubulin/metabolismABSTRACT
OBJECTIVES: Various models of spinal cord injury in rodents have been established, and also techniques for lesion quantification. Measurement of the extent of the underlying injury is essential for monitoring the reproducibility of the experimental injury and assessment of therapeutic effects. In this study, we tested manganese-enhanced magnetic resonance imaging (MEMRI) for postmortem quantification of experimental spinal cord injury in rats. MATERIALS AND METHODS: Twelve rats were subjected to contusion injuries at the 11th thoracic vertebra, followed by MnCl2 injections into the cisterna magna. After 3 days of observation, postmortem MEMRI-features were correlated with values of locomotion testing and histology. RESULTS: MnCl2 yielded a strong contrast enhancement of the uninjured spinal cord, whereas no enhancement was observed at the injury site or caudally. Magnetic resonance imaging findings correlate closely with locomotor ratings. CONCLUSIONS: MEMRI represents a reliable method for visualization and functional assessment of spinal cord integrity in rats.