Activation of protease-activated receptor 2 stimulates proliferation and interleukin (IL)-6 and IL-8 secretion of endometriotic stromal cells.
BACKGROUND
Inflammation has been proposed to play essential roles in the pathophysiology of endometriosis, in which neutrophils and mast cells have been suggested to be involved. We studied whether the protease-activated receptor 2 (PAR2), which is activated by enzymes from neutrophils and mast cells, in endometriotic stromal cells (ESC) has any implication in the development of the disease.


METHODS
Cultured ESC were stimulated with various concentrations of a specific PAR2 agonist peptide. Proliferating activity of the cells was determined using immunostaining of proliferating cell nuclear antigen (a cell proliferation marker), 5-bromo-2'-deoxyuridine incorporation into DNA and cell count. The concentrations of interleukin (IL)-6 and IL-8 were measured using specific enzyme-linked immunosorbent assay kits. The phosphorylation of three mitogen-activated protein kinases (MAPK), i.e. p38 MAPK, p42/44 MAPK and stress-activated protein Kinase/c-jun N terminal Kinase, in ESC was examined with Western blot analysis.


RESULTS
Activation of PAR2 stimulated the proliferation of ESC and the secretion of IL-6 and IL-8 from ESC in a dose-dependent manner. Activation of PAR2 stimulated the phosphorylation of all three MAPK, and inhibitors of each MAPK suppressed the PAR2 activation-induced proliferation of ESC.


CONCLUSIONS
The activation of PAR2 in ESC may be involved in the pathophysiology of endometriosis by inducing the growth and inflammation of endometriotic lesions.
Hirota
Yasushi
Y
Department of Obstetrics and Gynecology, Faculty of Medicine, University of Tokyo, 7-3-1, Hongo, Tokyo, 113-8655, Japan.
Osuga
Yutaka
Y
Hirata
Tetsuya
T
Harada
Miyuki
M
Morimoto
Chieko
C
Yoshino
Osamu
O
Koga
Kaori
K
Yano
Tetsu
T
Tsutsumi
Osamu
O
Taketani
Yuji
Y
D015153:Blotting, Western; D001973:Bromodeoxyuridine / Q000494:pharmacology; D002452:Cell Count; D049109:Cell Proliferation; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004715:Endometriosis / Q000473:pathology; D004717:Endometrium / Q000473:pathology*; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D015850:Interleukin-6 / Q000096:biosynthesis* / Q000378:metabolism; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000378:metabolism; D020935:MAP Kinase Signaling System; D008407:Mast Cells / Q000166:cytology*; D009504:Neutrophils / Q000378:metabolism*; D010766:Phosphorylation; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D044464:Receptor, PAR-2 / Q000737:chemistry / Q000378:metabolism*; D017154:Stromal Cells / Q000166:cytology / Q000378:metabolism* / Q000473:pathology; D013997:Time Factors
D004791:Enzyme Inhibitors; D015850:Interleukin-6; D016209:Interleukin-8; D018809:Proliferating Cell Nuclear Antigen; D044464:Receptor, PAR-2; D004247:DNA; D001973:Bromodeoxyuridine