Kere Michel, Liu Pan-Chen, Chen Yuh-Kun, Chao Pei-Chi, Tsai Li-Kuang, Yeh Ting-Yu, Siriboon Chawalit, Intawicha Payungsuk, Lo Neng-Wen, Chiang Hsing-I, Fan Yang-Kwang, Ju Jyh-Cherng
Department of Animal Science, National Chung Hsing University, 250 Kuo Kuang Road, Taichung 402, Taiwan.
Institute of Rural Development, Nazi Boni University, 01 P.O. Box 1091 Bobo-Dioulasso 01, Burkina Faso.
Animals (Basel). 2020 Apr 11;10(4):664. doi: 10.3390/ani10040664.
This study aimed to investigate ultrastructural changes of growing porcine oocytes and in vitro maturated oocytes. Light microscopy was used to characterize and localize the primordial, primary, secondary, and tertiary follicles. During oocyte growth and maturation, the morphology of mitochondria was roundish or ovoid in shape depending on the differentiation state, whereas their mean diameters oscillated between 0.5 and 0.7 µm, respectively, from primary and secondary follicles. Hooded mitochondria were found in the growing oocytes of the tertiary follicles. In addition to the pleomorphism of mitochondria, changes in the appearance of lipid droplets were also observed, along with the alignment of a single layer of cortical granules beneath the oolemma. In conclusion, our study is apparently the first report to portray morphological alterations of mitochondria that possess the hooded structure during the growth phase of porcine oocytes. The spatiotemporal and intrinsic changes during oogenesis/folliculogenesis are phenomena at the ultrastructural or subcellular level of porcine oocytes, highlighting an in-depth understanding of oocyte biology and impetus for future studies on practical mitochondrion replacement therapies for oocytes.
本研究旨在探究生长中的猪卵母细胞和体外成熟卵母细胞的超微结构变化。利用光学显微镜对原始卵泡、初级卵泡、次级卵泡和三级卵泡进行特征描述和定位。在卵母细胞生长和成熟过程中，线粒体的形态根据分化状态呈圆形或椭圆形，而初级卵泡和次级卵泡中线粒体的平均直径分别在0.5至0.7微米之间波动。在三级卵泡的生长中的卵母细胞中发现了带帽线粒体。除了线粒体的多形性外，还观察到脂滴外观的变化，以及卵黄膜下单层皮质颗粒的排列。总之，我们的研究显然是第一份描绘猪卵母细胞生长阶段具有带帽结构的线粒体形态改变的报告。卵子发生/卵泡发生过程中的时空和内在变化是猪卵母细胞超微结构或亚细胞水平的现象，突出了对卵母细胞生物学的深入理解，并为未来卵母细胞实际线粒体替代疗法的研究提供了动力。
