Of Salamanders and Spiny Mice: Common Features of Regeneration and Stem Cells
Purpose of Review
This review identifies the salient cellular and molecular features of regeneration of the skin and limbs of salamanders to see whether any of these features are in common with recent reports on the spiny mouse (Acomys), a mammal with some remarkable regenerative behavior. Other reports of mammalian regeneration are also highlighted.
Mammals have classically been regarded as non-regenerating, but the regeneration of several embryonic and post-natal tissues as well as reports of adult skin and ear hole regeneration have recently been described. Common features of these regenerating systems and those of salamanders are discussed in terms of their immune systems, cytokine responses, matrix composition, and matrix metalloproteinases (MMP) activation as well as the occurrence of blastemas in these diverse organisms. The common involvement of stem cells in regenerating systems is also addressed.
Mammals may not have lost all their regenerative powers, and a more diverse approach across other new model systems may reveal surprising behavior such as that seen in Acomys, the spiny mouse. Mammalian regenerating tissues share many common features with the champions of regeneration, the salamanders.
KeywordsAxolotl Spiny mouse Acomys Regeneration Skin wounding Blastema
Unpublished work from the author mentioned in the text was supported by a grant from the W. M. Keck Foundation.
Compliance with Ethical Standards
Conflict of Interest
Malcolm Maden declares that he has no conflict of interest.
Human and Animal Rights
All the reported studies with animal subjects performed by the author have complied with all applicable ethical standards following the guidelines of the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health and protocols approved by the Institutional Animal Care and Use Committee at the University of Florida.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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