Salamander Insights Into Ageing and Rejuvenation

Abstract

Exhibiting extreme regenerative abilities which extend to complex organs and entire limbs, salamanders have long served as research models for understanding the basis of vertebrate regeneration. Yet these organisms display additional noteworthy traits, namely extraordinary longevity, indefinite regenerative potential and apparent lack of traditional signs of age-related decay or “negligible senescence.” Here, I examine existing studies addressing these features, highlight outstanding questions, and argue that salamanders constitute valuable models for addressing the nature of organismal senescence and the interplay between regeneration and ageing.

Long-Term Rearing of Two Cynops Species and Fertility of Old Cynops ensicauda popei (Amphibia: Urodela)

“…The longevities of animals correlate with their body size, but some salamanders have longer longevities relative to body sizes (Sousounis et al, 2014). A factor contributing to their relatively long longevities might be their resistance to aging process (Yun, 2021).…”

“…The longevity of animals is strongly correlated with their body sizes, but some salamanders have longer longevities than those expected from their body sizes (Yun, 2021) (e.g., Proteus anguinus are: 100 years [Voituron et al, 2011;Tacutu et al, 2018], S. salamandra: 50 years [Böhme, 1979], Andrias japonicus: 55 years, Ambystoma maculatum: 25 years, Am. tigrinum: 25 years, Amphiuma means: 27 years, Cryptobranchus alleganiensis: 25 years, Siren lacertina: 25 years [Carey and Judge, 2000;de Magalhāes and Costa, 2009;Wells, 2010]).…”

Regenerative hallmarks of aging: Insights through the lens ofPleurodeles waltl

“…An increased accumulation of senescent cells could also account for the delay in regeneration from older newts. Senescent cells secrete numerous growth factors, proteases, cytokines, chemokines, and matrix remodeling proteins that can negatively impact several stages of regeneration (Yu and Yun, 2020;Yun, 2021). The importance of clearing senescent cells in mammalian tissues was highlighted by Baker et al, where genetic targeting of senescent cells was shown to alleviate cellular dysfunction caused by aging (Baker et al, 2011).…”

Editorial: Mechanisms and Pathways Contributing to the Diversity of Aging Across the Tree of Life

“…Most articles in our Research Topic set their work in a comparative (cross-species) context, and some also highlight the value of undertaking detailed studies using non-canonical model organisms. For example, Yun (2021) provides a fascinating perspective on the regenerative abilities of salamanders. These exceptionally long-lived animals can famously regrow limbs and even complex organs and are also markedly cancer-resistant.…”