Intracrine sex steroid synthesis and signaling in human epidermal keratinocytes and dermal fibroblasts.
Peripheral intracrine sex steroid synthesis from adrenal precursors dehydroepiandrosterone (DHEA) and DHEA-sulfate has evolved in humans. We sought to establish if there are differences in intracrine, paracrine, and endocrine regulation of sex steroids by primary cultures of human skin epidermal keratinocytes and dermal fibroblasts. Microarray analysis identified multifunctional genes modulated by steroids, quantitative RT-PCR (qRT-PCR) mRNA expression, enzymatic assay aromatase activity, scratch assay cell migration, immunocytochemistry α-smooth muscle actin (α-SMA), and collagen gel fibroblast contraction. All steroidogenic components were present, although only keratinocytes expressed the organic anion organic anion transporter protein (OATP) 2B1 transporter. Both expressed the G-protein-coupled estrogen receptor (GPER1). Steroids modulated multifunctional genes, up-regulating genes important in repair and aging [angiopoietin-like 4 (ANGPTL4), chemokine (C-X-C motif) ligand 1 (CXCL1), lamin B1 (LMNB1), and thioredoxin interacting protein (TXNIP)]. DHEA-sulfate (DHEA-S), DHEA, and 17β-estradiol stimulated keratinocyte and fibroblast migration at early (4 h) and late (24-48 h) time points, suggesting involvement of genomic and nongenomic signaling. Migration was blocked by aromatase and steroid sulfatase (STS) inhibitors confirming intracrine synthesis to estrogen. Testosterone had little effect, implying it is not an intermediate. Steroids stimulated fibroblast contraction but not α-SMA expression. Mechanical wounding reduced fibroblast aromatase activity but increased keratinocyte activity, amplifying the bioavailability of intracellular estrogen. Cultured fibroblasts and keratinocytes provide a biologically relevant model system to investigate the complex pathways of sex steroid intracrinology in human skin.
Centre for Skin Sciences, School of Life Sciences University of Bradford, Bradford, United Kingdom; Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Padua, Italy; and.
Elena
E
Pomari
Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Padua, Italy; and.
Luisa
L
Dalla Valle
Cutech, Padua, Italy.
Paolo
P
Pertile
Comparative Endocrinology Laboratory, Department of Biology, University of Padova, Padua, Italy; and.
Lorenzo
L
Colombo
Centre for Skin Sciences, School of Life Sciences University of Bradford, Bradford, United Kingdom; m.j.thornton@bradford.ac.uk.
M Julie
MJ
Thornton
D000199:Actins / Q000378:metabolism; D000328:Adult; D001141:Aromatase / Q000378:metabolism; D002470:Cell Survival; D002478:Cells, Cultured; D002784:Cholesterol / Q000378:metabolism; D003687:Dehydroepiandrosterone / Q000737:chemistry; D019314:Dehydroepiandrosterone Sulfate / Q000737:chemistry; D003907:Dexamethasone / Q000378:metabolism; D000078404:Epidermal Cells; D004958:Estradiol / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D012739:Gonadal Steroid Hormones / Q000096:biosynthesis*; D006801:Humans; D007150:Immunohistochemistry; D015603:Keratinocytes / Q000166:cytology*; D008875:Middle Aged; D016685:Mitomycin / Q000737:chemistry; D009130:Muscle, Smooth / Q000166:cytology; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction; D012867:Skin / Q000166:cytology*; D014945:Wound Healing
D000199:Actins; D012739:Gonadal Steroid Hormones; D012333:RNA, Messenger; D003687:Dehydroepiandrosterone; D004958:Estradiol; D016685:Mitomycin; D019314:Dehydroepiandrosterone Sulfate; D003907:Dexamethasone; D002784:Cholesterol; D001141:Aromatase
DHEA; aromatase; estradiol; testosterone; wound healing