Regenerative capacity in newts is not altered by repeated regeneration and ageing

National Institute for Basic Biology, National Institutes of Natural Sciences, Nishigonaka 38, Myodaiji, Okazaki, Aichi 444-8585, Japan.
Nature Communications (Impact Factor: 11.47). 07/2011; 2(1):384. DOI: 10.1038/ncomms1389
Source: PubMed


The extent to which adult newts retain regenerative capability remains one of the greatest unanswered questions in the regeneration field. Here we report a long-term lens regeneration project spanning 16 years that was undertaken to address this question. Over that time, the lens was removed 18 times from the same animals, and by the time of the last tissue collection, specimens were at least 30 years old. Regenerated lens tissues number 18 and number 17, from the last and the second to the last extraction, respectively, were analysed structurally and in terms of gene expression. Both exhibited structural properties identical to lenses from younger animals that had never experienced lens regeneration. Expression of mRNAs encoding key lens structural proteins or transcription factors was very similar to that of controls. Thus, contrary to the belief that regeneration becomes less efficient with time or repetition, repeated regeneration, even at old age, does not alter newt regenerative capacity.

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    • "In fact, there are several reports with opposing results. In newts, for example, the entire eye lens can regenerate and neither repeated regeneration nor old age altered the regenerative capacity of the lens (Eguchi et al., 2011). In zebrafish, two studies reported that old animals show impaired fin regeneration and that the time to regenerate 50% of the fin increased with advanced age (Tsai et al., 2007; Anchelin et al., 2011). "
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    • "These patterns suggest that regenerative ability is associated with age-related changes in cells that form tissues and organs, as well as maturation of systems that broadly regulate development and physiology (Seifert and Voss, 2013). Exceptions include lens regeneration in adult newts (Eguchi et al., 2011) and fin regeneration in zebrafish (Itou et al., 2012). "
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    Full-text · Article · Jun 2014
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    • "Normally developed out of the epidermis at the embryonic stage, the lens re-emerges in a stepwise fashion from the edge of the iris instead (Henry and Tsonis 2010). Neither age nor repeated amputation seems to diminish this regenerative capability (Eguchi et al. 2011). But it turns out that an injection of the growth factor, FGF2, is all it takes to trigger the onset of development (Hayashi et al. 2004), along with the subsequent expression of other genes. "
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