Re‐epithelialization of large wound in paedomorphic and metamorphic axolotls

Abstract

Axolotls (Ambystoma mexicanum) may heal their skin wounds scar-free in both paedomorphs and metamorphs. In previous studies on small punch skin wounds, rapid re-epithelialisation was noted in these two axolotl morphs. However, large wound size in mammals may affect wound healing. In this study, large circumferential full thickness excision wounds on the hind limbs were created on juvenile paedomorphic and metamorphic axolotls. The results showed re-epithelialisation was more quickly initiated in paedomorphs than in metamorphs after wounding. The migrating rate of epidermis on the wound bed was faster in paedomorphs than in metamorphs and thus completion of re-epithelialisation was faster in paedomorphs than in metamorphs. Within these re-epithelialisation periods, neither basement membrane nor dermis was reformed. Epidermal cell proliferation was detected by EdU-labelling technique. In the normal unwounded skin, epidermal proliferation rate was higher in paedomorphs than in metamorphs. After wounding, the epidermal proliferation rate was significantly lower in the migrating front on the wound bed than in the normal skin in paedomorphs. The EdU-labelling rate between normal skin and migration front was not different in metamorphs. Lacking of more proliferating epidermal cells on the wound bed indicated that the new epidermis here derived rather from migrating epidermal cells than from cell proliferation in situ. In conclusion, re-epithelialisation in the large wound might be fully completed in both morphs despite it was initiated earlier and with faster rate in paedomorphs than in metamorphs. The new epidermis on the wound bed derived mainly from cell migration than by cell proliferation in the re-epithelialisation period. J. Morphol. 278:228-235, 2017. © 2016 Wiley Periodicals,Inc.

A Double Fluorescence Chimeric Limb Regeneration Model Reveals Muscle Fiber Reconnection During Axolotl Limb Regeneration

“…Husbandry of axolotls and ethics statement. Adult or juvenile axolotls (Ambystoma mexicanum) were kept separately in individual fish tanks in an aquaria system as previously described (Wu et al, 2017;Huang et al, 2017). Animal care and experiments were approved by the Institutional Animal Care and Use Committee of National Taiwan University College of Medicine (Permit number: 20160535) and were conducted in accordance with the approved guidelines.…”

Axolotls’ and Mices’ Oral-Maxillofacial Trephining Wounds Heal Differently

“…This exploratory study overviews the relatively early phases of wound healing including: haemorrhage/hemostasis [Oakley and Larjava, 2012], epithelial migration [Larjava et al, 2012;Huang et al, 2017], and the inflammatory response [Turabelidze and DiPietro, 2012;Seifert and Maden, 2014] after a similar wound in both animals' tongues and intermandibular regions. We expected the wounds to create observable and quantifiable data highlighting certain important differences in these animals early wound responses.…”

Inhibiting fibroblast aggregation in skin wounds unlocks developmental pathway to regeneration

“…in Schmidt Ullrich and Paus, 2005) has far outpaced our knowledge of dermal development (Driskell et al, 2013; Van Exan and Hardy, 1984). Renewed interest into the scar-free healing ability of salamanders (Cook and Seifert, 2016; Erickson and Echeverri, 2018; Huang et al, 2017; Levesque et al, 2010; Seifert et al, 2012b; Weiss and Ferris, 1956) and frogs (Bertolotti et al, 2013; Otsuka-Yamaguchi et al, 2017; Seifert and Maden, 2014; Yokoyama et al, 2011b) has exposed a relatively sparse literature on skin development in urodeles (Gerling et al, 2012; Hay and Revel, 1963; Pederzoli et al, 2002; Salpeter and Singer, 1959; Weiss and Ferris, 1954). Instead, most of our knowledge of amphibian skin development comes from work in anurans (rev.…”