Department of Theriogenology, University of Veterinary and Animal Sciences, Outfall Road Lahore, 54000, Pakistan.
Reproduction Division, Buffalo Research Institute, Pattoki, 55300, Pakistan.
Theriogenology. 2024 Sep 15;226:219-227. doi: 10.1016/j.theriogenology.2024.06.008. Epub 2024 Jun 14.
During in-vitro maturation, the oocyte experiences stressful conditions that likely compromise its development. Epinephrine is a catecholamine that plays a vital role during cellular stress by scavenging free radicals. The hypothesis is that epinephrine addition in maturation media improves the developmental competence of oocytes in cattle and buffalo. The objectives of the experiments were to investigate the effect of epinephrine addition in maturation media on nuclear maturation, developmental competence, and oocyte mRNA abundance of genes related to antioxidants and growth pathways in cattle and buffalo. In experiment 1, cattle oocytes were matured for 24 h in maturation media supplemented with increasing concentrations of epinephrine 0, 0.01, 1.0, and 100 μM. Oocytes were cultured to assess cleavage at 48 h and blastocyst on day 7 of the culture. The cumulus-oocyte complexes (COCs) expansion, nuclear maturation, and oocyte mRNA abundance of genes (SOD1, GPX4, GDF9, CASP9) were evaluated. In experiment 2, buffalo oocytes were matured and assessed for development and mRNA abundance as described for cattle. In addition, the blastomere number was counted in the hatched blastocyst. The data were analyzed using GLIMMIX and MIXED procedures of SAS. Results revealed that the supplementation of epinephrine increased (P ≤ 0.03) the COCs expansion, nuclear maturation, and developmental competence of oocytes in cattle. Interestingly, all the responses were maximized (quadratic effect; P ≤ 0.08) at 1 μM concentrations. The mRNA abundance of genes in cattle oocytes was not affected by the treatment. The experiment in buffalo revealed that epinephrine increased blastocyst formation without affecting COCs expansion, and nuclear maturation. The higher blastocyst was achieved at 0.01 μM concentrations of epinephrine. Interestingly, the addition of epinephrine increased the mRNA abundance of genes related to antioxidant pathways (SOD1, GPX4). Moreover, supplementation of epinephrine increased the blastomere count of the hatched blastocyst in buffalo. In conclusion, epinephrine addition in maturation media benefited oocyte development in cattle and blastocyst yield in buffalo at 1 and 0.01 μM concentrations, respectively. It appears that the addition of epinephrine affected different cellular pathways, COCs expansion, and nuclear maturation in cattle and increased antioxidant genes for buffalo.
在体外成熟过程中，卵母细胞经历应激条件，这可能会损害其发育。肾上腺素是一种儿茶酚胺，在细胞应激时通过清除自由基发挥重要作用。假设在成熟培养基中添加肾上腺素可以提高牛和水牛卵母细胞的发育能力。实验的目的是研究在成熟培养基中添加肾上腺素对牛和水牛卵母细胞核成熟、发育能力以及与抗氧化和生长途径相关的基因的 mRNA 丰度的影响。在实验 1 中，牛卵母细胞在成熟培养基中培养 24 小时，成熟培养基中添加了不同浓度的肾上腺素 0、0.01、1.0 和 100 μM。在 48 小时评估卵裂情况，在培养的第 7 天评估囊胚。评估卵丘-卵母细胞复合物（COC）扩张、核成熟和与抗氧化和生长途径相关的基因（SOD1、GPX4、GDF9、CASP9）的卵母细胞 mRNA 丰度。在实验 2 中，按照牛的描述对水牛卵母细胞进行成熟和评估发育以及 mRNA 丰度。此外，在孵化的囊胚中计数卵裂球数。使用 SAS 的 GLIMMIX 和 MIXED 程序分析数据。结果表明，肾上腺素的补充增加了（P≤0.03）牛卵母细胞 COC 扩张、核成熟和发育能力。有趣的是，所有反应在 1 μM 浓度时达到最大值（二次效应；P≤0.08）。牛卵母细胞基因的 mRNA 丰度不受处理的影响。在水牛的实验中，肾上腺素增加了囊胚的形成，而不影响 COC 扩张和核成熟。在 0.01 μM 浓度的肾上腺素时获得了更高的囊胚。有趣的是，添加肾上腺素增加了与抗氧化途径相关的基因（SOD1、GPX4）的 mRNA 丰度。此外，在水牛中，添加肾上腺素增加了孵化囊胚的卵裂球数。总之，在成熟培养基中添加肾上腺素分别有利于牛卵母细胞的发育和水牛囊胚的产量，浓度分别为 1 和 0.01 μM。似乎肾上腺素的添加影响了牛的不同细胞途径、COC 扩张和核成熟，并增加了水牛的抗氧化基因。
