Avian uterine fluid proteome: Exosomes and biological processes potentially involved in sperm survival

• Published in: Molecular reproduction and development 2020-04, Vol.87 (4), p.454-470
• Main Authors: Riou, Cindy, Brionne, Aurélien, Cordeiro, Luiz, Harichaux, Grégoire, Gargaros, Audrey, Labas, Valérie, Gautron, Joël, Gérard, Nadine
• Format: Article
• Language: English
• Subjects: Animals; Annexin A4 - metabolism; avian; Biological Phenomena; Biomarkers - metabolism; Body Fluids - chemistry; Body Fluids - metabolism; Chickens - physiology; Electron microscopy; Epithelium; Exosomes; Exosomes - chemistry; Exosomes - metabolism; Female; Genital tract; Immunoblotting; Immunohistochemistry; Life Sciences; Male; Microscopy; Other; PARK7 protein; Protein Deglycase DJ-1 - metabolism; Proteome; Proteomes; Proteomics; Reproductive Biology; Semen; Semen - chemistry; Semen - metabolism; Sperm; Spermatozoa - metabolism; Survival; Tubules; uterine fluid; Uterus; Uterus - metabolism; Valosin Containing Protein - metabolism
• ISSN: 1040-452X; 1098-2795
• DOI: 10.1002/mrd.23333

Uterine fluid is an aqueous milieu to which sperm are exposed during their storage and ascent. In this study, a bottom‐up proteomic strategy and bioinformatic analysis of hen uterine fluid was performed to improve the understanding of this fluid and its potential role in sperm survival mechanisms. The proteomic data were submitted to ProteomeXchange. Among the 913 proteins identified, 160 are known to be secreted and 640 are referenced in exosomes databases. We isolated exosomes from the avian uterine fluid, analyzed them using electron microscopy, and targeted several exosomes markers (ANXA1/2/4/5, VCP, HSP90A, HSPA8, PARK7, and MDH1) using immunoblotting. Electron microscopy and immunohistochemistry were also used to analyze uterovaginal junctions for the exosomal proteins ANXA4, VCP, and PARK7. Exosomes were observed both at the surface epithelium and inside sperm storage tubules. Our data were compared with two previously published studies on proteomic of hen uterine fluid, and with one study describing the proteomic content of rooster seminal plasma and sperm. In conclusion, we demonstrated for the first time that avian uterine fluid contains exosomes. These may play a key role in preserving sperm functions within the female genital tract. Their presence in the sperm storage tubules may represent an important mechanism regarding interaction between the female genital tract and sperm. A bottom‐up proteomic strategy and bioinformatic analysis of hen uterine fluid (UF) was performed to improve the understanding of this fluid and its role in sperm survival. Among the 913 proteins identified, 640 are referenced in exosome databases. Electron microscopy, immunohistochemistry, and immunoblotting approches demonstrated for the first time that avian UF contains exosomes. Their presence in the sperm storage tubules may represent an important novel mechanism regarding interaction between the female genital tract and sperm involved in sustained sperm survival.