Follicular extracellular vesicles enhance meiotic resumption of domestic cat vitrified oocytes

• Published in: Scientific reports Vol. 10; no. 1; p. 8619
• Main Authors: de Almeida Monteiro Melo Ferraz, Marcia, Fujihara, Mayako, Nagashima, Jennifer Beth, Noonan, Michael James, Inoue-Murayama, Miho, Songsasen, Nucharin
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 25-05-2020; Nature Publishing Group
• Subjects: 1-Phosphatidylinositol 3-kinase; 631/1647/2067; 631/61/2296; 82/58; AKT protein; Animals; Apolipoproteins; Calcium signalling; Cats; Cholesterol; Cluster Analysis; Cryopreservation; Domestic animals; Embryos; Extracellular matrix; Extracellular vesicles; Extracellular Vesicles - metabolism; Extracellular Vesicles - ultrastructure; Female; Fertility; Follicular fluid; Follicular Fluid - metabolism; Gametes; Genes; Genomes; Gluconeogenesis; Glycolysis; Glycolysis - genetics; Humanities and Social Sciences; Lipid metabolism; Lipids; MAP kinase; Meiosis; MicroRNAs; Microscopy, Electron, Transmission; multidisciplinary; Ontology; Oocytes; Oocytes - cytology; Oocytes - metabolism; Oxidative Phosphorylation; Phosphorylation; Proteins; Proteome - analysis; Proteomes; Proteomics - methods; Reproductive technologies; Roles; Science; Science (multidisciplinary); Signal Transduction - genetics; Sperm; Thawing; Transmission electron microscopy; Vitrification
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-65497-w

Extracellular vesicles (EVs) contain multiple factors that regulate cell and tissue function. However, understanding of their influence on gametes, including communication with the oocyte, remains limited. In the present study, we characterized the proteome of domestic cat (
Felis catus
) follicular fluid EVs (ffEV). To determine the influence of follicular fluid EVs on gamete cryosurvival and the ability to undergo
in vitro
maturation, cat oocytes were vitrified using the Cryotop method in the presence or absence of ffEV. Vitrified oocytes were thawed with or without ffEVs, assessed for survival,
in vitro
cultured for 26 hours and then evaluated for viability and meiotic status. Cat ffEVs had an average size of 129.3 ± 61.7 nm (mean ± SD) and characteristic doughnut shaped circular vesicles in transmission electron microscopy. Proteomic analyses of the ffEVs identified a total of 674 protein groups out of 1,974 proteins, which were classified as being involved in regulation of oxidative phosphorylation, extracellular matrix formation, oocyte meiosis, cholesterol metabolism, glycolysis/gluconeogenesis, and MAPK, PI3K-AKT, HIPPO and calcium signaling pathways. Furthermore, several chaperone proteins associated with the responses to osmotic and thermal stresses were also identified. There were no differences in the oocyte survival among fresh and vitrified oocyte; however, the addition of ffEVs to vitrification and/or thawing media enhanced the ability of frozen-thawed oocytes to resume meiosis. In summary, this study is the first to characterize protein content of cat ffEVs and their potential roles in sustaining meiotic competence of cryopreserved oocytes.