Exogenous γ-tocotrienol promotes preimplantation development and improves the quality of porcine embryos

Abstract

γ-tocotrienol (GTT), an isomer of vitamin E, has been the subject of increasing interest due to its strong anti-oxidant effects. Therefore, in this study, the effects of GTT on blastocyst development, expression levels of reactive oxygen species (ROS) and apoptotic index were investigated in preimplantation porcine embryos. After in vitro maturation and fertilisation, porcine embryos were cultured for 6 days in porcine zygote medium 3 supplemented with or without GTT (200μM) under oxidative stress conditions (200μM hydrogen peroxide (H2O2)). Blastocyst development was significantly improved in the GTT-treated group when compared with the H2O2-treated group (P<0.05). Subsequent evaluation of the intracellular levels of ROS and numbers of apoptotic nuclei in GTT-treated blastocysts revealed that ROS levels of GTT-treated porcine blastocysts were decreased (P<0.05) and the numbers of apoptotic nuclei were reduced by GTT treatment in porcine embryos. Moreover, the total cell numbers of blastocysts were significantly increased in the GTT-treated group relative to the untreated group under H2O2-induced oxidative stress (P<0.05). The expression levels of apoptosis-related genes (BCL-XL, BAX) in GTT-treated blastocysts were then investigated using real-time reverse transcription polymerase chain reaction. Expression of the anti-apoptotic BCL-XL gene was shown to be increased in the GTT-treated blastocyst group, whereas expression of the pro-apoptotic BAX gene was decreased. Taken together, these results suggest that GTT (200μM) under H2O2-induced oxidative stress, thereby improving the developmental competence of porcine embryos via modulation of intracellular levels of ROS and the apoptotic index during the preimplantation stage.

Native plants (Phellodendron amurense and Humulus japonicus) extracts act as antioxidants to support developmental competence of bovine blastocysts

“…Apoptosis is an important indicator used in evaluation of blastocyst quality [ 8 ]. In a previous study, we demonstrated that decreasing apoptosis enhanced blastocyst quality, while high apoptosis rate reduced blastocyst quality [ 27 ]. Apoptosis, which is known to be one of the mechanisms involved in the mitochondrial pathway, is activated by caspase-8 and -9 via the mitochondrial pathways.…”

Ganglioside GM3 induces cumulus cell apoptosis through inhibition of epidermal growth factor receptor‐mediated PI3K/AKT signaling pathways during in vitro maturation of pig oocytes

“…In vitro maturation of oocytes was performed as described by Lee et al (), with slight modifications. Pig ovaries were collected from a local slaughterhouse and transported to our laboratory at 35°C in 0.9% saline supplement with 75 µg/ml potassium penicillin G. Immature COCs, between 3 and 6 mm in diameter, were aspirated from ovary follicles into a 10‐ml syringe with an 18‐gauge needle.…”

Vitamin E as an Antioxidant in Female Reproductive Health

“…Meanwhile, co-administration with γ-TCT improved the embryonic development in nicotine-induced mice [ 64 ]. Moreover, as reported in more recent findings, using co-incubation in media supplemented with γ-TCT and hydrogen peroxide (H 2 O 2 ), γ-TCT improved the development of porcine embryos through modulation of the apoptotic BCL-XL and BAX genes [ 135 ]. The beneficial effects of TCTs were also supported by the reports on the concomitant supplementation of TRF with the anti-cancer prodrug, cyclophosphamide (CPA) on ovarian cells, which was reported to provide protection against OS-induced apoptosis in the ovaries [ 132 , 133 ].…”