National Experimental Teaching Demonstration Center of Animal Medicine Foundation, College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, 163319, PR China.
College of Veterinary Medicine, Jilin University, Changchun, 130062, PR China.
Cryobiology. 2021 Jun;100:125-132. doi: 10.1016/j.cryobiol.2021.02.008. Epub 2021 Feb 27.
Cold stress is one of the serious factors restricting the development of animal husbandry in cold areas. Cold exposure can easily lead to cold stress, slow growth and even death of newborn animals. O-GlcNAcylation modification can act as type of "stress receptor" and"nutrition sensor" in a variety of stress responses, however, it is not clear how O-GlcNAcylation can regulate glucose metabolism in the liver of piglets under cold stress. In this study, piglets 21 days of age were exposed to 4 °C for 4 h or 8 h in a phytotron. Serum cortisol and other stress hormones were used to assess body status to establish a cold stress piglet model. The changes of glycogen in liver were detected by PAS. FDP and PA were also measured to study the glycolysis level of liver. To characterize potential mechanisms of O-GlcNAcylation on the livers of cold stress piglets, AKT, GSK3β, GS, PFKFB2, AS160 and their corresponding phosphorylation were determined by Western blotting. Results show O-GlcNAcylation increased and apoptosis levels increased in the liver following cold exposure during excessive CORT or metabolic dysfunction. It is suggested that the acute cold exposure of piglets induced a sequential change in the level of O-GlcNAcylation, which may be one of the factors mediating liver cell apoptosis and glucose metabolism regulation by the O-GlcNAc/AKT pathway. These findings provide new insight into the mechanisms of the cold stress response, which can facilitate the development of new strategies to combat the effects of hypothermia.
冷应激是限制寒冷地区畜牧业发展的严重因素之一。冷暴露容易导致新生动物冷应激、生长缓慢甚至死亡。O-GlcNAc 修饰可以作为多种应激反应中的“应激感受器”和“营养传感器”,然而,O-GlcNAc 如何调节冷应激仔猪肝脏中的葡萄糖代谢尚不清楚。在这项研究中,21 日龄仔猪在人工气候室内暴露于 4°C 4 小时或 8 小时。通过测定血清皮质醇和其他应激激素来评估机体状态,以建立冷应激仔猪模型。通过 PAS 检测肝脏中糖原的变化。还测定了 FDP 和 PA 以研究肝脏的糖酵解水平。为了研究 O-GlcNAc 化在冷应激仔猪肝脏中的潜在作用机制,通过 Western blot 测定 AKT、GSK3β、GS、PFKFB2、AS160 及其相应磷酸化水平。结果表明,冷暴露后,CORT 过多或代谢功能障碍会导致肝脏中 O-GlcNAc 化增加和细胞凋亡水平增加。这表明,仔猪急性冷暴露诱导 O-GlcNAc 化水平的顺序变化,这可能是 O-GlcNAc/AKT 通路介导肝细胞凋亡和葡萄糖代谢调节的因素之一。这些发现为冷应激反应的机制提供了新的见解,有助于开发新的策略来对抗低温的影响。