Sato Daichi, Itami Nobuhiko, Tasaki Hidetaka, Takeo Shun, Kuwayama Takehito, Iwata Hisataka
Tokyo University of Agriculture, Funako, Atugi City, Japan.
PLoS One. 2014 Apr 18;9(4):e94488. doi: 10.1371/journal.pone.0094488. eCollection 2014.
The present study assessed the effect of resveratrol on the expression of SIRT1 and mitochondrial quality and quantity in porcine oocytes. Supplementing the maturation medium with 20 µM resveratrol increased the expression of SIRT1, and enhanced mitochondrial functions, as observed from the increased ATP content and mitochondrial membrane potential. Addition of resveratrol also improved the ability of oocytes to develop into the blastocyst stage following activation. The effects of resveratrol on mitochondrial number were examined by comparing the mitochondrial DNA copy number (Mt number) between group of oocytes collected from the same donor gilt ovaries. Supplementing the maturation medium with only resveratrol did not affect the Mt number in the oocytes. However, supplementing the maturation medium with 10 µM MG132, a proteasome inhibitor, significantly increased the amount of ubiquitinated proteins and Mt number by 12 and 14%, respectively. In addition, when resveratrol was added to the medium containing MG132, the Mt number increased significantly by 39%, this effect was diminished by the addition of the SIRT1 inhibitor EX527. Furthermore, supplementing the medium with MG132 and EX527 did not affect Mt number. The mean SIRT1 expression in 20 oocytes was significantly and positively correlated with the Mt number in oocytes collected from the same donor. This study suggests that the expression of SIRT1 is associated with the Mt number in oocytes. In addition, activation of SIRT1 by resveratrol enhances the biosynthesis and degradation of mitochondria in oocytes, thereby replenishing and improving mitochondrial function and the developmental ability of oocytes.
本研究评估了白藜芦醇对猪卵母细胞中SIRT1表达以及线粒体质量和数量的影响。在成熟培养基中添加20µM白藜芦醇可增加SIRT1的表达，并增强线粒体功能，这可从ATP含量增加和线粒体膜电位升高观察到。添加白藜芦醇还提高了卵母细胞激活后发育到囊胚阶段的能力。通过比较从同一供体母猪卵巢采集的卵母细胞组之间的线粒体DNA拷贝数（Mt数），研究了白藜芦醇对线粒体数量的影响。仅在成熟培养基中添加白藜芦醇不会影响卵母细胞中的Mt数。然而，在成熟培养基中添加10µM蛋白酶体抑制剂MG132，可分别使泛素化蛋白量和Mt数显著增加12%和14%。此外，当将白藜芦醇添加到含有MG132的培养基中时，Mt数显著增加39%，添加SIRT1抑制剂EX527可减弱这种作用。此外，在培养基中添加MG132和EX527不会影响Mt数。从同一供体采集的20个卵母细胞中的平均SIRT1表达与卵母细胞中的Mt数显著正相关。本研究表明，SIRT1的表达与卵母细胞中的Mt数相关。此外，白藜芦醇激活SIRT1可增强卵母细胞中线粒体的生物合成和降解，从而补充和改善线粒体功能以及卵母细胞的发育能力。
