جستجوی مقالات مرتبط با کلیدواژه « fertilization » در نشریات گروه « دامپزشکی »

The effects of MitoTEMPO, a mitochondria-targeted antioxidant, and its non-targeted parent, TEMPO, on bovine oocyte maturation competence have not been determined so far. Hence, our study was aimed to investigate the effects of supplementing maturation medium with different concentrations of MitoTEMPO (0.00, 0.10, 1.00 and 10.00 µM) or TEMPO (0.00, 5.00, 10.00 and 15.00 mM) on in vitro maturation (IVM) and fertilization (IVF) of bovine oocytes. The oocytes after IVM and IVF were evaluated for the signs of nuclear maturation and normal fertilization. The average number of spermatozoa penetrated per oocyte and the level of intracellular reactive oxygen species (ROS) were also evaluated. The results showed that percentages of bovine oocytes reached the metaphase II stage of meiosis were significantly higher in the 1.00 µM MitoTEMPO group compared to the control group (without antioxidant supplementation). The normal fertilization rate also tended to be greater in this group than the control group. In comparison with the control group, the medium supplementation with 1.00 µM MitoTEMPO led to a significant decrease in the intracellular ROS level. The average number of spermatozoa penetrated per oocyte was not significantly different among the antioxidant-treated and the non-treated groups. The TEMPO addition to the maturation medium affected neither the rate of maturation/fertilization nor the level of intracellular ROS in bovine oocytes. Based on these results, we concluded that MitoTEMPO at a concentration of 1.00 µM had beneficial effects on the quality and fertilization potential of bovine oocytes.

The aim of this study was to determine the potential fertilizing of spermatozoa from the epididymal tail in different periods of time post-orchiectomy (P-OQ). Therefore, the study was approached in two stages. In the first stage, the orchiectomy was performed in 30 adult pigs. The testicles were stored at 5.00 ˚C in physiological saline solution for 5, 24, 48, 72, 96 and 120 hr. The spermatozoa were obtained by backflushing the vas deferens. The spermogram and fluorometric study were performed for each sample to evaluate the exposure of phosphatidyl-serine (PS) and acrosome reaction (AR). The second stage included the fertilization test, 16 prepubertal sows were selected, after synchronizing the oestrous cycle and the post-cervical artificial insemination was performed with the refrigerated sperm samples from each P-OQ time. The percentage of live sperm remained without significant changes until 96 hr P-OQ. An increase in the percentage of spermatozoa that showed a PS exposure was observed. The premature AR was evident after 72 hr. Considering that the artificial insemination was performed ensuring a minimum number of live sperms, no significant differences were observed in the number of embryos and corpora lutea. The results indicated that pig sperm collected from the epididymal tail P-OQ and stored for 5 and up to 72 hr at 5.00 ˚C had viable characteristics and maintained their fertilization ability. However, there was an increase in the loss of phospholipid asymmetry of the plasma membrane as time increased (72 and 96 hr), therefore, sperm viability was decreased.

Docetaxel is beneficial in oocyte cryopreservation.

The effect of docetaxel, on the survival, fertilization rate and mRNA expression of apoptosis-related genes of vitrified mature oocytes was investigated.

Mature oocytes were divided into eight experimental groups, including I) control, II) docetaxel, III) docetaxel + cryoprotectant agent 1 (CPA1), IV) docetaxel + CPA2, V) docetaxel + vitrification 1 (Vit1), VI) docetaxel + Vit2, VII) Vit1, and VIII) Vit2. The survival and fertilization rates, and the mRNA expression level of Bcl-xl, Bax and caspase-3 as apoptosis-related genes were evaluated.

The survival rates in Vit1, and Vit2 groups were significantly lower than in the control group (P<0.05). The fertilization rates in docetaxel + Vit1, docetaxel + Vit2, Vit1, and Vit2 were significantly lower than the control, docetaxel, and related groups using docetaxel and CPAs. Bax expression was significantly increased in groups which oocytes vitrified. Also, its expression in the Vit2 group increased significantly in comparison to the docetaxel + Vit2 group. The expression of the Bcl-xl gene was downregulated in docetaxel + CPA2, docetaxel + Vit2 and Vit2 compared to docetaxel group. The Bax/Bcl-xl ratio significantly increased in docetaxel + CPA2, docetaxel + Vit1, docetaxel + Vit2, Vit1 and Vit2 groups compared to control, docetaxel and the docetaxel + CPA1 group. Caspase-3 expression significantly increased in all six groups in comparison to the control, and docetaxel groups. Its expression significantly increased in the Vit1 and Vit2 groups in comparison with docetaxel + Vit1, and docetaxel + Vit2, respectively.

Docetaxel ameliorates the damages to oocytes during vitrification by altering the expression of apoptosis-related genes and its effects are dependent on the vitrification solution used in cryopreservation of oocytes.