Accumulation of reactive oxygen species leads to oxidative stress condition that can accelerate ovarian aging. Ovarian aging caused a reduction in plasma estradiol levels, quality of embryo and eventually will lead to infertility. Tocotrienol has been proven to possess antioxidant properties by protecting the cellular membrane from free radicals damage. Therefore, the aim of this study was to determine the effect of tocotrienol supplementation on the plasma estradiol levels, quality and development of embryos in aging mice. Female mice (Mus musculus) used in this study were divided into six groups. Six weeks old mice (young group) were used as negative control while eight months old mice (aging group) were used as age-matched (positive control) group. Group 1 (6 months old mice) were given corn oil as control, group 2, 3 and 4 (6 months old mice) were supplemented orally for two months with tocotrienol (TCT) at the dose of 90, 120 and 150 mg/kg body weight (BW), respectively. Subsequently, after two months the mice were superovulated, euthanized and 2- cell stage embryos were harvested and cultured in vitro to monitor the embryonic development. Plasma was analysed using enzyme-like immunosorbent assay. The results of this study showed that there was no significant correlation between plasma estradiol levels and the quality of embryo between young and aging group. Similarly, no significant change on plasma estradiol levels were noted in all TCT supplemented groups as compared to its vehicle control. On the other hand, there was a significant reduction on the percentage of normal embryo in all aging groups including TCT supplemented groups as compared to young group. Conversely, TCT supplementation at the dose of 150 mg/kg BW was able to increase the percentage of embryos that developed to blastocyst stage as compared to control. This finding proposed that TCT supplementations for two months are not able to cause a significant change in plasma estradiol levels and quality of embryo but it can delay the consequence of aging in embryonic development.
Penuaan ovari telah dikaitkan dengan tekanan oksidatif dan kehilangan fungsi ovari. Tokotrienol telah dibuktikan dapat memberi kesan yang baik terhadap sistem pembiakan wanita. Walau bagaimanapun, peranan tokotrienol ke atas metabolisma ovari dan seterusnya peningkatan kualiti oosit dalam mencit tua masih tidak diketahui. Oleh itu, hubungan antara perubahan aktiviti metabolik dalam ovari dan kualiti oosit dalam mencit tua selepas suplementasi fraksi kaya tokotrienol (TRF) telah dikaji. Mencit betina berusia enam minggu digunakan sebagai kumpulan Muda. Mencit betina berusia enam bulan dibahagikan kepada empat kumpulan iaitu kumpulan pertama yang diberikan minyak jagung-bebas tokoferol (kawalan) manakala tiga kumpulan yang lain diberi suplimen TRF pada dos 90, 120, dan 150 mg/kg. Rawatan diberikan secara oral selama dua bulan. Pada akhir rawatan, mencit dari semua kumpulan disuperovulasi dan kemudian dikorbankan. Kualiti oosit dinilai dan analisis metabolomik secara tidak disasarkan, pada tisu ovari dijalankan dengan menggunakan 'liquid chromatography tandem mass spectrometry of quadrupole time-of-flight' (LC-MS Q-TOF). Peratusan oosit normal adalah lebih tinggi (p