氨是畜舍和大气环境中的重要污染物,过量的氨会损害牲畜和饲养员的健康。先前的研究表明,氨暴露可能会损害神经系统的组织结构,但氨引起下丘脑损伤的分子机制尚不清楚。本研究的目的是确定过量的氨在猪下丘脑异常自噬中的作用以及硒代蛋氨酸是否会对氨毒性产生缓解作用。24只18周龄猪随机分为4组:对照组(C组),硒组(Se组),氨+硒组(A+Se组),和氨组(A组)。在我们的研究中,NF-κB的表达水平,IL-1β,iNOS,TNF-α,IKK-α,p-IKK-α,Nrf2,ATG5,ATG10,ATG12,LC3I/II,氨暴露后HSP60、HSP70和HSP90升高;同时,IFN-γ,IKB-α,p-IKB-α,Keap1,P62,mTOR,AKT,p-AKT,PI3K,SQSTM,Beclin1呈下降趋势。结果表明,过量吸入氨通过氧化应激介导的猪下丘脑炎症反应抑制AKT/mTOR通路促进自噬。L-硒代蛋氨酸可减轻氨暴露引起的下丘脑损伤。
Ammonia is a significant pollutant in the livestock houses and the atmospheric environment, and excessive ammonia would harm the health of livestock and breeders. Previous studies have shown that ammonia exposure could damage the tissue structure of the nervous system, but the molecular mechanism of ammonia-induced hypothalamus damage was still unclear. The purpose of this study was to determine the role of excessive ammonia in abnormal autophagy of pig hypothalamus and whether selenomethionine would have a mitigating effect on ammonia toxicity. Twenty-four 18-week pigs were randomly divided into four groups: the control group (C group), the selenium group (Se group), the ammonia + selenium group (A + Se group), and the ammonia group (A group). In our study, the expression levels of NF-κB, IL-1β, iNOS, TNF-α, IKK-α, p-IKK-α, Nrf2, ATG5, ATG 10, ATG 12, LC3 I/II, HSP60, HSP70, and HSP90 were increased after ammonia exposure; meanwhile, IFN-γ, IKB-α, p-IKB-α, Keap1, P62, mTOR, AKT, p-AKT, PI3K, SQSTM, and Beclin1 showed decreasing trends. The results indicated that excessive ammonia inhalation inhibited the AKT/mTOR pathway to acclerated autophagy through oxidative stress-mediated inflammation in the porcine hypothalamus. L-selenomethionine could alleviate hypothalamus injury induced by ammonia exposure.