“Fibronectin from oviductal cells fluctuates during the estrous cycle and contributes to sperm-oviduct interaction in cattle”

OSYCKA-SALUT, CE; CASTELLANO, L; FORNES, D; BELTRAME, JS; ALONSO, CAI; JAWERBAUM, A; FRANCHI, A; DÍAZ, ES; PEREZ MARTINEZ, S

JOURNAL OF CELLULAR BIOCHEMISTRY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2017

0730-2312

During the passage of sperm through the oviduct, spermatozoa bind to the oviductalepithelium and form the oviductal reservoir. This interaction keeps the fertilizing capacity ofsperm until ovulation-associated signals induce sperm release from the oviductal epithelium,allowing the transit of spermatozoa to the fertilization site.Fibronectin is a glycoprotein from the extracellular matrix that binds to α5β1 receptors.Fibronectin has been found to be expressed in the oviduct, whereas α5β1 has been found tobe expressed in the sperm of different species. Fibronectin is involved through α5β1 in spermfunctions.The aim of this work was to study the participation of oviductal fibronectin in the regulationof the sperm-oviduct interaction in cattle. We found that oviductal epithelial cellsdifferentially expressed all mRNA splice variants of fibronectin during the estrous cycle.Fibronectin was localized in the apical region of oviductal epithelial cells and fibronectinlevels in the oviductal fluid fluctuated during the estrous cycle. Also, bovine spermatozoaexpressed α5β1. Using in vitro sperm-oviduct co-cultures, we found that spermatozoa wereattached to the oviductal epithelium through α5β1. The incubation of co-cultures withfibronectin induced sperm release from the oviductal cells through α5β1. The spermpopulation released from oviductal cells by fibronectin was enriched in motile andcapacitated spermatozoa. Based on our in vitro culture system results, we propose thatfibronectin and α5β1 are involved in the sperm-oviduct interaction. Also, an increase infibronectin levels in the oviductal fluid during the pre-ovulatory period may promote spermrelease from the oviductal epithelium in cattle. This article is protected by copyright. All rightsreserved