Department of Physiology, College of Wildlife Resources, Northeast Forestry University, Harbin, 150040, Heilongjiang, People's Republic of China.
Environ Sci Pollut Res Int. 2018 Jul;25(19):18662-18672. doi: 10.1007/s11356-018-2059-2. Epub 2018 Apr 28.
Arsenic trioxide (AsO), the most toxic form of arsenic found in foodstuffs, is considered a carcinogen for human and animal. But many of the events that occur during its passage through the gastrointestinal tract are uncharted in birds. This study assesses the toxic effect on the jejunum of chicken which subchronically exposed to diets that contain AsO (0, 0.625, 1.25, 2.5 mg/kg body weight) for 90 days. Electron microscopy, TdT-mediated dUTP nick-end labeling (TUNEL), qPCR, and Western blot were performed. The results showed that mitochondrial fusion and apoptosis inhibiting genes had degressive trends, whereas mitochondrial fission and apoptosis activating genes presented heightened expressions in the treatment group compared with the control (P < 0.05). Subsequently, significant inhibition in PI3K/AKT/mTOR signaling was observed. Moreover, the expression of autophagy markers (LC3-II/LC3-I, Beclin-1) increased time and dose-dependently. Additionally, metabolic disorders of trace elements were detected evidenced by their significant decreases (aluminum, silicon, calcium, manganese, strontium, titanium, lithium, boron, cobalt, mercury, chromium) and increases (arsenic, cadmium, selenium, lead, nickel) on 90 days using inductively coupled plasma mass spectrometer (ICP-MS). It is possible that the changes of trace elements have a hand in the come on and development of arsenism. Taken together, we conjectured that, in chicken jejunum, arsenic led to redistribution of trace elements, promoting apoptosis via regulating mitochondrial dynamics, leading to autophagy through PI3K/AKT/mTOR signal pathways.
三氧化二砷(AsO)是食物中发现的最具毒性的砷形式,被认为对人类和动物具有致癌性。但是,在鸟类的胃肠道中,其通过的许多事件都尚未被研究过。本研究评估了三氧化二砷(AsO)(0、0.625、1.25、2.5mg/kg 体重)亚慢性暴露于饮食中的鸡空肠的毒性作用,持续 90 天。进行了电子显微镜、TdT 介导的 dUTP 缺口末端标记(TUNEL)、qPCR 和 Western blot。结果表明,与对照组相比,线粒体融合和凋亡抑制基因呈下降趋势,而线粒体分裂和凋亡激活基因呈升高趋势(P<0.05)。随后,观察到 PI3K/AKT/mTOR 信号通路的显著抑制。此外,自噬标志物(LC3-II/LC3-I、Beclin-1)的表达呈时间和剂量依赖性增加。此外,通过电感耦合等离子体质谱(ICP-MS)检测到微量元素的代谢紊乱,其含量在 90 天内显著降低(铝、硅、钙、锰、锶、钛、锂、硼、钴、汞、铬)和增加(砷、镉、硒、铅、镍)。可能是微量元素的变化参与了砷中毒的发生和发展。综上所述,我们推测在鸡空肠中,砷通过调节线粒体动力学导致微量元素重新分布,促进细胞凋亡,通过 PI3K/AKT/mTOR 信号通路导致自噬。