June 2015 (No. 1)
Astaxanthin present in the maturation medium reduces negative effects of heat shock on the developmental competence of porcine oocytes
Lanh Thi Kim Do a, Vien Viet Luu a, Yasuhiro Morita a, Masayasu Taniguchi a, Masahiro Nii b, Augustine T. Peter c, Takeshige Otoi a,*
a Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan
b Tokushima Prefectural Livestock Research Institute, Tokushima, Japan
c Department of Veterinary Clinical Sciences, Purdue University, West Lafayette, IN, USA
Astaxanthin, one of the most common carotenoids, elicits antioxidant effects on cellular viability and embryonic development. This study was conducted to investigate the effects of astaxanthin on maturation, fertilization and development of porcine oocytes matured in vitro under heat stress conditions, and then fertilized and cultured under standard conditions. Porcine oocytes were cultured in maturation medium supplemented with different concentrations of astaxanthin (0, 0.25, 0.5 or 1 ppm) for 46 h at either 38.5 or 41 °C. In comparison to oocytes cultured at 38.5 °C, the exposure of porcine oocytes to 41.0 °C during in vitro maturation (IVM) significantly inhibited maturation and development of fertilized oocytes to the blastocyst stage. Supplementation of maturation medium with astaxanthin (0.5 ppm) significantly improved oocyte maturation, fertilization and develop-ment to the blastocysts stage in both oocyte groups. However, the total cell number and apoptosis index of blastocysts did not differ among groups. Moreover, astaxanthin (0.5 ppm) significantly increased the rate of oocytes that reached metaphase II and decreased propor-tion of apoptotic oocytes exposed to H2O2 (1.0 mM) during IVM. In summary, we demon-strated that supplementation of maturation medium with astaxanthin (0.5 ppm) exerted antioxidative effects and improved the ability of maturation, fertilization, and development of porcine oocytes exposed to heat stress.
Reproductive Biology 2015, 15 (2):
* Corresponding author at: Laboratory of Animal Reproduction, The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi 753-8515, Japan. E-mail address: email@example.com (T. Otoi).