Throughout human life, many cells such as hair follicles and certain tissues such as liver can be continuously replaced to maintain tissue integrity in response to normal, daily wear and tear. However, the human response to more serious tissue damage, such as acute damage to limbs or to the spinal cord, is limited to relatively simple wound healing, whereby collagenous scar tissue fills the injury site, assuring the tissue’s structural integrity but often resulting in a debilitating loss of functional activity. While humans do exhibit some very limited regenerative capacity (e.g. finger tips), other vertebrates exhibit sometimes astonishing regenerative ability. Salamanders show the highest diversity in being able to regenerate limbs, tail, heart, eyes and jaw
Our aim is to understand at the molecular and cellular level how an axolotl spinal cord can functionally repair after injury and why mammals cannot. To this end we have used transcriptional profiling to identify key differences at the miRNA level between axolotl and rat after spinal cord injury. In particular we are focusing on the differences between the rostral and caudal sides of the injury site and how the axolotl creates a permissive environment for axonal regrowth while mammals do not. We are focusing not just on the neuronal cells but also on the contribution and interaction of the other cells especially endothelial cells and skin to this repair process.
(For a comprehensive list of recent publications, refer to PubMed, a service provided by the National Library of Medicine.)
- Echeverri K, Zayas RM. Regeneration: From cells to tissues to organisms. Dev Biol. 2018;433:109-110.
- Erickson JR, Echeverri K. Learning from regeneration research organisms: The circuitous road to scar free wound healing. Dev Biol. 2018;433:144-154.
- Diaz Quiroz JF, Li Y, Aparicio C, Echeverri K. Development of a 3D matrix for modeling mammalian spinal cord injury in vitro. Neural Regen Res. 2016;11:1810-1815.
- Erickson JR, Gearhart MD, Honson DD, Reid TA, Gardner MK, Moriarity BS, Echeverri K. A novel role for SALL4 during scar-free wound healing in axolotl. NPJ Regen Med. 2016;1. pii: 16016.
- Sabin K, Santos-Ferreira T, Essig J, Rudasill S, Echeverri K. Dynamic membrane depolarization is an early regulator of ependymoglial cell response to spinal cord injury in axolotl. Dev Biol. 2015;408:14-25.
- Pai VP, Martyniuk CJ, Echeverri K, Sundelacruz S, Kaplan DL, Levin M. Genome-wide analysis reveals conserved transcriptional responses downstream of resting potential change in Xenopus embryos, axolotl regeneration, and human mesenchymal cell differentiation. Regeneration (Oxf). 2015;3(1):3-25
- Gearhart MD, Erickson JR, Walsh A, Echeverri K. Identification of conserved and novel microRNAs during tail regeneration in the Mexican axolotl. Int J Mol Sci. 2015;16:22046-22061.
- Erickson JR, Echeverri K. In vivo modulation and quantification of microRNAs during axolotl tail regeneration. Methods Mol Biol. 2015;1290:159-67.
- Diaz Quiroz JF, Tsai E, Coyle M, Sehm T, Echeverri K. Precise control of miR-125b levels is required to create a regeneration-permissive environment after spinal cord injury: a cross-species comparison between salamander and rat. Dis Model Mech. 2014;7(6):601-11.
- Diaz Quiroz JF, Echeverri K. Spinal cord regeneration: where fish, frogs and salamanders lead the way, can we follow? Biochem J. 2013;451(3):353-64.