Key Laboratory of Molecular Animal Nutrition, Ministry of Education, College of Animal Sciences, Zhejiang University, Hangzhou, China.
Biol Trace Elem Res. 2020 Aug;196(2):481-493. doi: 10.1007/s12011-019-01948-4. Epub 2019 Nov 15.
The current study aimed to investigate the influence of four supplemental zinc salts (chelated: Zn glycine; non-chelated: Zn sulfate, Zn citrate, Zn gluconate) among different zinc concentrations (30-300 μM) on cell proliferation, oxidative stress, and energy depletion in intestinal porcine jejunum epithelial cells (IPEC-J2). Different zinc salts affected cell viability in a time- and dose-dependent manner, which was mainly dependent on the uptake of intracellular Zn. Intracellular Zn of Zn sulfate has taken up almost twice as high as Zn glycine when cells were loaded with 100-200 μM zinc. After loading cells with 300 μM zinc, Zn glycine and Zn sulfate had a similar trend in accumulation of Zn. When the intracellular Zn overloads, cells will gradually be damaged and subsequently die bearing biochemical features of necrosis or late apoptosis. Meanwhile, obviously, increased levels of intracellular ROS, mitochondrial ROS, MDA, and NO and decreased levels of GSH were observed. Excessive intracellular Zn significantly decreased mitochondria membrane potential accompanied by an obvious loss of ATP and NAD levels. Overall, exposure to high doses of zinc salts caused cell damage, which was mainly dependent on the uptake of Zn. Zinc overload induced oxidative stress and energy depletion in IPEC-J2 cells, and the cell damage with non-chelated zinc addition was more serious than Zn glycine.
本研究旨在探讨不同锌浓度（30-300 μM）下四种补充锌盐（螯合：Zn 甘氨酸；非螯合：Zn 硫酸盐、Zn 柠檬酸盐、Zn 葡萄糖酸盐）对猪肠上皮细胞（IPEC-J2）增殖、氧化应激和能量耗竭的影响。不同的锌盐以时间和剂量依赖的方式影响细胞活力，这主要取决于细胞内 Zn 的摄取。当细胞加载 100-200 μM 锌时，Zn 硫酸盐摄取的细胞内 Zn 几乎是 Zn 甘氨酸的两倍。当细胞加载 300 μM 锌后，Zn 甘氨酸和 Zn 硫酸盐在 Zn 的积累上有相似的趋势。当细胞内 Zn 过载时，细胞会逐渐受损，随后以坏死或晚期凋亡的生化特征死亡。同时，观察到细胞内 ROS、线粒体 ROS、MDA 和 NO 水平明显升高，GSH 水平降低。过量的细胞内 Zn 显著降低了线粒体膜电位，同时伴随着 ATP 和 NAD 水平的明显下降。总的来说，高剂量的锌盐暴露会导致细胞损伤，这主要取决于 Zn 的摄取。Zn 过载诱导 IPEC-J2 细胞氧化应激和能量耗竭，并且添加非螯合锌导致的细胞损伤比 Zn 甘氨酸更严重。
