哺乳动物低氧应激代谢成因的研究进展

氧气是哺乳动物机体代谢稳态维持的物质基础,若代谢过程中氧气供给不足,可造成低氧应激。目前,环境低氧、代谢性低氧和携氧细胞功能障碍是造成动物低氧应激的重要成因。目前,低氧对动物机体代谢和组织功能的影响研究主要集中于肺脏、肝脏、消化道、肌肉和乳腺等部位。若处于低氧状态的哺乳动物形成了适应低氧的代谢模式,则可维持其代谢稳态;相反,若动物无法维持低氧状态下的代谢稳态,则会导致机体氧化应激甚至病变。目前,低氧应激在家畜方面的研究主要集中于高原动物代谢适应机制;然而,泌乳期动物机体代谢速率、氧气消耗和自由基水平均较高,但氧在泌乳动物代谢应激形成中的作用及其对泌乳性能的影响,仍有待探索。综述了哺乳动物产生低氧应激的代谢成因与作用结果,旨在探讨哺乳动物低氧应激生物学基础,为进一步从低氧应激调控角度为泌乳动物的健康状况维持提供理论依据。

Research Progress on Metabolic Causes for Hypoxic Stress in Mammalian Animals

Oxygen is the material basis for maintaining the metabolic homeostasis of mammals.If the oxygen supply is insufficient during the metabolic process,it can cause hypoxic stress.Environmental hypoxia,metabolic hypoxia,and oxygen-carrier dysfunction are known as the key causes of hypoxic stress.The impact of hypoxia on the body metabolism and tissue function of mammals were mainly conducted in lung,liver,digestive tract,muscle,and mammary gland,etc.It can maintain its metabolic homeostasis if a mammal in a hypoxic state has developed a metabolic pattern adapted to hypoxia.On the contrary,if the animal cannot maintain metabolic homeostasis under hypoxic conditions,it will cause oxidative stress or even pathological changes.At present,the research on hypoxic stress in livestock mainly focuses on the metabolic adaptation mechanism of plateau animals;however,the metabolic rate,oxygen consumption and free radical levels of lactating animals are relatively high,but the role of oxygen in the formation of metabolic stress in lactating animals and impact on lactation performance are still under being explored.The current review summarized the causes and consequences of hypoxic stress,aimed to discuss the biological basis of mammalian hypoxic stress,and to provide a theoretical basis for maintaining the health status of lactating animals from the perspective of hypoxic stress.