295 EFFECT OF TREHALOSE DURING IN VITRO MATURATION OF PIG OOCYTES ON OOCYTE MATURATION AND EMBRYONIC DEVELOPMENT AFTER PARTHENOGENESIS
Y. Jeon A , B. Baasanjav A , Y. I. Jeong A , Y. W. Jeong A , Y. W. Kim A , S. H. Hyun B , I. S. Yang A and W. S. Hwang AA Sooam Biotech Research Foundation, Seoul, Republic of Korea;
B Laboratory of Veterinary Embryology and Biotechnology (VETEMBIO), College of Veterinary Medicine, Chungbuk National University, Cheongju, Republic of Korea
Reproduction, Fertility and Development 27(1) 236-237 https://doi.org/10.1071/RDv27n1Ab295
Published: 4 December 2014
Abstract
Autophagy is a critical process for the maintenance of cellular homeostasis and mammalian early embryogenesis. Autophagy can be regulated by various chemical inducers. However, there are few reports about effect of autophagy inducer in vitro maturation (IVM) of porcine oocyte. The present study investigated the effects of supplementary trehalose, a novel mTOR-independent autophagy enhancer, on oocyte maturation and embryonic development after parthenogenetic activation (PA). Immature oocytes were treated with various concentrations (0, 25, 50, and 100 mM) of trehalose in M-199 (Invitrogen, Carlsbad, CA) supplemented with 10 ng mL–1 of epidermal growth factor (EGF; Sigma-Aldrich Corp.), 1 ug mL–1 of insulin (Sigma-Aldrich Corp.), 4 IU mL–1 of pregnant mare serum gonadotropin (PMSG; Intervet, Boxmeer, Holland), 4 IU mL–1 of human chorionic gonadotropin (hCG; Intervet), and 10% (vol/vol) porcine follicular fluid (pFF) for 10 h, and transferred to another IVM medium without trehalose. Osmolality of each groups (0, 25, 50, and 100 mM trehalose) was in the 290 to 295, 310 to 315, 330 to 335, and 375 to 380 osmol range, respectively. After 44 h of IVM, trehalose treatment during IVM did not improve nuclear maturation rates of oocytes in any group (90.7, 92.1, 92.7, and 90.1%, respectively). The developmental competence of oocytes matured with different trehalose concentrations was evaluated after PA. There were no significant differences in cleavage rates. However, blastocyst (BL) formation was different. Oocytes treated with 25 mM of trehalose during IVM had a significantly higher (P < 0.05) BL formation rate (64.2%) after PA compared with the control (52.0%). The BL quality was also improved in the 25 mM trehalose-treated group. Early BL rate significantly reduced in the 25 mM trehalose-treated group as compared to control (19.6 v. 29.9%, P < 0.05). By contrast, expanded BL rate significantly increased in the 25 mM trehalose-treated group than of control (27.7 v. 11.0%, P < 0.05). Total cell numbers of BL were significantly higher (P < 0.05) in the 25 mM trehalose-treated group compared to those in the control group (52.2 v. 36.8). However, BL rate and quality of oocytes treated with 50 and 100 mM trehalose were similar with control group. In conclusion, these results indicate that 25 mM trehalose during IVM improved the developmental potential of porcine embryos. Trehalose will be useful for large-scale production of BL with good quality in porcine in vitro production.
This work was supported by a grant from the Next-Generation Bio Green 21 Program (No. PJ009563032014), Rural Development Administration, Republic of Korea.