title: 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.
authors.affiliation: Liver Disease Prevention and Treatment Research Foundation, Taipei, Taiwan.
authors.forename: Ting-Yu
authors.initials: TY
authors.lastname: Huang
authors.affiliation: Department of Entomology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.|Institute of Biotechnology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.
authors.forename: Chun-Che
authors.initials: CC
authors.lastname: Chang
authors.affiliation: Department of Surgery, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Nai-Chen
authors.initials: NC
authors.lastname: Cheng
authors.affiliation: Institute of Biotechnology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.
authors.forename: Mu-Hui
authors.initials: MH
authors.lastname: Wang
authors.affiliation: Liver Disease Prevention and Treatment Research Foundation, Taipei, Taiwan.
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Chiou
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Kuang-Lun
authors.initials: KL
authors.lastname: Lee
authors.affiliation: Institute of Biotechnology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.|Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.|Agricultural Biotechnology Research Center, Academia Sinica, Taipei, Taiwan.
authors.forename: Hsuan-Shu
authors.initials: HS
authors.lastname: Lee
mesh_terms: D000558:Ambystoma mexicanum / Q000502:physiology*; D000818:Animals; D004817:Epidermis / Q000378:metabolism; D062326:Re-Epithelialization / Q000502:physiology*
keywords: axolotl; cell migration; metamorphosis; re-epithelialisation; wound healing