Li Xiaoya, Wu Qiong, Gao Huimin, Cheng Jianyong, Chen Huali, Duan Jiaxin, Sun Wu, Zhang Zelin, Yang Li, Hua Rongmao, Li Lan, Li Qingwang, Jiang Zhongliang
College of Animal Science and Technology, Qingdao Agricultural University, Qingdao, 266109, PR China; College of Animal Science and Technology, Northwest A&F University, Yangling, 712100, PR China.
College of Medical, Qinghai University, Qinghai, 810001, PR China.
Free Radic Biol Med. 2025 Sep;237:239-250. doi: 10.1016/j.freeradbiomed.2025.05.418. Epub 2025 May 30.
Because of the increased global warming, heat stress (HS) damage to animals reproduction has become an inevitable and urgent problem to be solved. The disruption of oocyte maturation caused by HS is considered the main cause of impaired reproductive ability. Particularly, porcine oocytes are more susceptible to HS damage due to their sensitivity to temperature changes and physiological characteristics of high lipid droplet content. At present, there is no effective antidote for HS damage. In mammalian ovaries, maintaining cumulus cells-oocyte communications promotes oocyte development. Isorhamnetin has various pharmacological activities. However, the effect of isorhamnetin in HS-induced oocyte damage and cumulus cells-oocyte communications are still unclear. Oocytes were cultured at 39 °C (control group) or 41.5 °C (HS group) for 44 h. Oocytes were treated with different concentrations isorhamnetin (5, 10, 20 and 30 μM) respectively, during heat stress. Nuclear maturation, blastocyst development, cumulus cells-oocyte communications, COCs function, ROS levels, mitochondrial function, apoptosis, calcium ion level, and endoplasmic reticulum distribution of oocytes were detected. Our study showed that isorhamnetin therapy prevented HS-damaged oocyte development. Isorhamnetin enhanced nuclear maturation and blastocyst development inhibited by HS. Meanwhile, isorhamnetin prevented cumulus cells-oocyte communications and cumulus cell proliferation damaged by HS. Isorhamnetin alleviated HS-induced mitochondrial dysfunction in porcine oocytes by maintaining cumulus cells-oocyte communications, thereby reducing ROS accumulation and enhancing mitochondrial function. Isorhamnetin inhibited HS-induced endoplasmic reticulum (ER) stress by decreasing Ca2+ levels and increasing normal ER distribution, which was blocked by carbenoxolone. These results suggest that maintaining cumulus cells-oocyte communications is an important mechanism by which isorhamnetin protects oocytes from HS-damage. Collectively, our data indicate that isorhamnetin enhances HS-damaged oocyte development by maintaining cumulus cells-oocyte communications to inhibit oxidative stress, apoptosis, mitochondrial dysregulation and ER stress, providing a new strategy to solve the threat of HS to animal and human reproduction.
由于全球变暖加剧，热应激（HS）对动物繁殖的损害已成为一个不可避免且亟待解决的问题。HS导致的卵母细胞成熟障碍被认为是生殖能力受损的主要原因。特别是，猪卵母细胞因其对温度变化的敏感性和高脂质滴含量的生理特性，更容易受到HS损害。目前，尚无针对HS损害的有效解毒剂。在哺乳动物卵巢中，维持卵丘细胞与卵母细胞的通讯可促进卵母细胞发育。异鼠李素具有多种药理活性。然而，异鼠李素在HS诱导的卵母细胞损伤及卵丘细胞与卵母细胞通讯方面的作用仍不清楚。将卵母细胞在39℃（对照组）或41.5℃（HS组）培养44小时。在热应激期间，分别用不同浓度的异鼠李素（5、10、20和30μM）处理卵母细胞。检测卵母细胞的核成熟、囊胚发育、卵丘细胞与卵母细胞通讯、卵丘-卵母细胞复合体（COCs）功能、活性氧（ROS）水平、线粒体功能、凋亡、钙离子水平以及内质网分布。我们的研究表明，异鼠李素治疗可防止HS损伤的卵母细胞发育。异鼠李素增强了被HS抑制的核成熟和囊胚发育。同时，异鼠李素防止了被HS破坏的卵丘细胞与卵母细胞通讯及卵丘细胞增殖。异鼠李素通过维持卵丘细胞与卵母细胞通讯，减轻了HS诱导的猪卵母细胞线粒体功能障碍，从而减少ROS积累并增强线粒体功能。异鼠李素通过降低钙离子水平并增加正常内质网分布，抑制了HS诱导的内质网（ER）应激，而这种作用被生胃酮阻断。这些结果表明，维持卵丘细胞与卵母细胞通讯是异鼠李素保护卵母细胞免受HS损害的重要机制。总体而言，我们的数据表明，异鼠李素通过维持卵丘细胞与卵母细胞通讯来抑制氧化应激、凋亡、线粒体失调和ER应激，从而增强HS损伤的卵母细胞发育，为解决HS对动物和人类繁殖的威胁提供了一种新策略。
