TITLE:
Wound Closure on the Neonatal Rat Skin II. The Potential Ability of Epidermis to Close Small-Sized Wounds Independently of the Underlying Dermis
AUTHORS:
Mary Arai, Takashi Matsuzaki, Setsunosuke Ihara
KEYWORDS:
Wound Closure; Reepithelialization; Rat; Neonate; Epidermis; Migration; Actomyosin; Rho Family Small GTPases
JOURNAL NAME:
CellBio,
Vol.2 No.4,
December
20,
2013
ABSTRACT: Reepithelialization of skin which comprises epidermis
and dermis has not been fully elucidated due to the complexity of the
participants as well as the interactions therein. In this study, the intrinsic
roles and behaviors of epidermis itself during wound closure
on neonatal rat skin were explored by developing and utilizing a novel in vivo wound model, termed “shallow
incisional wound” in which the injury of dermis was minimized. The shallow
wounds were closed by 12 h postwounding (PW) by the migration of the
wound-marginal epidermal sheets in which activated myosin light chain (p-MLC)
was predominantly detected at the lateral plasma membrane of individual cells. By
local administration of Rho-associated protein kinase (ROCK) inhibitor Y27632,
p-MLC disappeared at the wound margin and wounds were not closed by 12 h PW. Inhibition of Rac 1 by NSC23766 also
resulted in hold of wound closure by 12 h PW, though NSC23766 somewhat slowly
acted on p-MLC expression. These results suggest that, without joining of
dermis, epidermal cells have a potential ability of closing wounds by active
epithelial sheet movement integrated by Rho family small GTPases-dependent
extension and contraction of the individual cell bodies.