Wound healing is a highly dynamic and complex process which involves
multiple kind of cells, extracellular matrix (ECM) and soluble molecules and it
consisted of slightly overlapped 4 phases, hemostasis, inflammation, proliferation
and remodeling. To find an agent to treat wound and accelerate wound healing, it
is required to trace the influence of the agent on 4 phases of wound healing.
The under shrub, Achillea asiatica Serg. which spreads across Mongolia, China,
Russia and Central Asia is reported that it has been used to heal inflammatory
diseases, enterogastritis and skin related problems in many countries. Even though,
extract of A.asiatica (AAE) has been studied for its effect of inducing gastric acid
secretion and anthelmintic, any research work has not been performed on its effect
on skin related diseases. Therefore, we have concentrated on revealing molecular
mechanism for wound healing in multiple cell lines.
To examine anti-inflammatory effect of AAE and its constituents, we have
evaluated its influence on release of inflammatory mediators and cytokine in
RAW264.7, murine macrophage cells. AAE and its compounds including luteolin
and apigenin have moderately reduced production of the inflammatory mediators
ii
such as nitric oxide (NO) and prostaglandin E2 (PGE2) and other cytokine
expressions like interleukin-1β (IL-1β), tumor necrosis factor?α (TNF-α) and
interleukin-6 (IL-6) in a dose-dependent manner.
Then, expressions of important molecules for keratinocyte migration and
differentiation in HaCaT human keratinocyte cell line were measured by western
blot analysis to evaluate influence of AAE on proliferation phase. The nuclear
translocation of β-catenin and phosphorylation of Akt protein increased in the
presence of AAE as well as chlorogenic acid and schaftoside, separated
compounds from AAE. Also expression of involucrin, the marker of keratinocyte
differentiation, was enhanced by treatment with AAE and chlorogenic acid and
schaftoside.
Finally, to estimate effect of AAE on ECM synthesis and remodeling, collagen
expression and activation of β-catenin and Smad2/3, which are important signaling
molecules for remodeling phase in Hs68 human dermal fibroblast cell lines were
assessed. The treatment of AAE induced collagen type I expression, while only
schaftoside increased collagen type III expression. In addition, AAE and
chlorogenic acid, schaftoside and apigenin-7-O-glucoside have stimulated
activation of β-catenin and phosphorylation of Smad2/3 proteins, a downstream
molecule of transforming growth factor-β (TGF-β) signaling.
In conclusion, based on these results, AAE may carry promising wound
healing potential in a way by reducing inflammation in tissue, enhancing
keratinocyte migration and proliferation and expression of extracellular matrix
molecules, especially collagen in fibroblast due to various major constituents.