Galectin-7 is important for normal uterine repair following menstruation.
Menstruation involves the shedding of the functional layer of the endometrium in the absence of pregnancy. At sites where tissue shedding is complete, re-epithelialization of the tissue is essential for repair and termination of bleeding. The complement of growth factors that mediate post-menstrual endometrial repair are yet to be completely elucidated. Galectins regulate many cell functions important for post-menstrual repair, such as cell adhesion and migration. Galectin-7 has a well characterized role in re-epithelialization and wound healing. We hypothesized that galectin-7 would be important in re-epithelialization during post-menstrual repair. We aimed to identify endometrial expression of galectin-7 in women undergoing normal endometrial repair and in women with amenorrhoea who do not experience endometrial breakdown and repair, and to determine whether galectin-7 enhances endometrial re-epithelialization in vitro. Galectin-7 immunolocalized to the endometrial luminal and glandular epithelium during the late secretory and menstrual phases, and to decidualized stroma in regions exhibiting tissue breakdown. Immunostaining intensity was significantly reduced in the endometrium of women with amenorrhoea compared with normally cycling woman. ELISA identified galectin-7 in menstrual fluid at significantly elevated levels compared with matched peripheral plasma. Exogenous galectin-7 (2.5 µg/ml) significantly enhanced endometrial epithelial wound repair in vitro; this was abrogated by inhibition of integrin binding. Galectin-7 elevated epithelial expression of extracellular matrix-related molecules likely involved in repair including β-catenin, contactin and TGF-β1. In conclusion, galectin-7 is produced by the premenstrual and menstrual endometrium, where it accumulates in menstrual fluid and likely acts as a paracrine factor to facilitate post-menstrual endometrial re-epithelialization.
Endometrial Remodelling Laboratory, MIMR-PHI Institute of Medical Research, Clayton, VIC 3168, Australia Department of Physiology, Monash University, Clayton, VIC 3800, Australia jemma.evans@princehenrys.org.
Jemma
J
Evans
Endometrial Remodelling Laboratory, MIMR-PHI Institute of Medical Research, Clayton, VIC 3168, Australia.
Joanne
J
Yap
Embryo Implantation Laboratory, MIMR-PHI Institute of Medical Research, Clayton, VIC 3168, Australia.
Thillini
T
Gamage
Endometrial Remodelling Laboratory, MIMR-PHI Institute of Medical Research, Clayton, VIC 3168, Australia Department of Obstetrics and Gynecology, Monash University, Clayton, VIC 3800, Australia.
Lois
L
Salamonsen
Department of Physiology, Monash University, Clayton, VIC 3800, Australia Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC 3800, Australia.
Evdokia
E
Dimitriadis
Department of Physiology, Monash University, Clayton, VIC 3800, Australia.
Ellen
E
Menkhorst
D002478:Cells, Cultured; D004717:Endometrium / Q000187:drug effects / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D037161:Galectins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D066298:In Vitro Techniques; D008597:Menstrual Cycle / Q000187:drug effects / Q000378:metabolism*; D008598:Menstruation / Q000378:metabolism*; D011247:Pregnancy; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D051176:beta Catenin / Q000378:metabolism
D037161:Galectins; C092525:LGALS7 protein, human; D053773:Transforming Growth Factor beta1; D051176:beta Catenin
endometrium; extracellular matrix; galectin-7; menstruation; repair