Rats and axolotls share a common molecular signature after spinal cord injury enriched in collagen-1

ABSTRACT Spinal cord injury (SCI) in mammals leads to irreversible tissue damage and loss of function. In contrast, axolotls are able to regenerate scar-free the injured spinal cord. To explore new pathological mechanisms, we compared rat versus axolotl transcriptomics and isolated genes shared between species post-SCI. Unexpectedly, multiple transcripts involved in extracellular matrix remodelling, in particular collagen-1, were upregulated in both species after SCI. Proteomics validated persistent expression of the collagen-enriched matrix signature at the protein level. Collagen-1 accumulated in early and advanced rat lesions. Importantly, collagen-1 was likely associated with pathological vascular remodelling rather than classic fibrosis and the transcription factor SP1 was predicted and validated to regulate, at least in part, the expression of collagen-1 in rat lesions.