Does Vitamin D Accelerate Cell Migration Via Estrogen Receptors in a Wound Healing Assay?

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SAT 338-357-Steroid Hormone Actions
Basic/Translational
Saturday, June 15, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SAT-355
Julie Thornton* and Safa Faraj
University of Bradford, Bradford, United Kingdom
Both estradiol and vitamin D improve wound healing in animal models. Migration of epidermal keratinocytes is required to re-epithelialize and restore the cutaneous barrier. We have previously demonstrated that 17β-estradiol can accelerate human keratinocyte migration in vitro, although we have not established whether it modulates this stimulatory effect via ERα, ERβ or the G-protein coupled ER (GPER). Since other studies have suggested some interplay between estrogen and vitamin D signalling, the aim of this study was to determine whether vitamin D has a similar effect on keratinocyte migration as estradiol, and if there is any interplay with estrogen action.

Human keratinocyte cell monolayers were mechanically wounded and cell migration measured after 2, 4, 6, 24 and 48h in the presence or absence of  17β-estradiol or cholecalciferol. In addition, the affect of both hormones was assessed in the presence of fulvestrant, a high affinity ERα and ERβ antagonist and GPER agonist, or G15 a high affinity and selective GPER antagonist with no affinity for ERα and ERβ.

All concentrations (1, 10 and 100nM) of 17β-estradiol accelerated cell migration as early as 2h and for up to 48h (p<0.05). Cholecalciferol had a similar stimulatory effect, which was significant at 100nM. Fulvestrant (10µM) completely blocked the stimulatory effect of both 17β-estradiol and cholecalciferol at all time points (p<0.05), but had no effect on its own. Similarly, G15 (10µM) inhibited the stimulatory effect of both 17β-estradiol and cholecalciferol at all time points (p<0.05), but had no effect on its own. When cells were incubated with both hormones together, the migratory response was significantly increased after 4h, but at later time points was the same as cells incubated with the hormones individually. The addition of G15 totally abolished the stimulatory effect with the combined hormones at all time points.

These results demonstrate that vitamin D has a similar stimulatory affect on human keratinocyte migration and that 17β-estradiol and vitamin D modulate cell migration through the same estrogen signalling pathways. Inhibition by both G15 and fulvestrant, while fulvestrant  alone had no stimulatory effect, suggests that the actions of GPER by itself are insufficient and either ERα or ERβ, or both are also required.

Nothing to Disclose: JT, SF

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm