Department of Military Hygiene, Second Military Medical University, No. 800 Xiangyin Road, Yangpu District, Shanghai, 200433, China.
Biol Trace Elem Res. 2012 Apr;146(1):79-85. doi: 10.1007/s12011-011-9230-7. Epub 2011 Oct 13.
We have previously demonstrated that psychological stress (PS) can cause iron to accumulate in the cerebral cortex, hippocampus, and striatum of rats. However, why iron accumulates and in what oxidation state iron it accumulates in the brain of PS-exposed rats has not been well elucidated. In the present study, we investigated the influence of PS on the low molecular weight iron pool (LMWIP) in the rat brain. The results showed that: (1) PS significantly expanded LMWIP in the cerebral cortex, hippocampus, and striatum in rats; (2) PS caused derangement of pyramidal cells and reduced the layers of pyramidal CA1 and CA2 neurons; (3) PS exposure greatly lowered the expression of ferritin (Fn) and hephaestin (HP) in the rat cortex and hippocampus; and (4) PS decreased superoxide dismutase, glutathione peroxidase, and glutathione level and increased malondialdehyde level in the cerebral cortex, hippocampus, and striatum in rats. These results indicated that PS could expand LMWIP significantly, which may be attributed to PS-induced decrease in Fn, HP expression, and the subsequent reduction in iron storage and utilization, and expansion of LMWIP could in turn lead to aggravation of oxidative damage.
我们之前的研究表明，心理应激（PS）可导致铁在大鼠大脑皮质、海马和纹状体中蓄积。然而，PS 暴露大鼠脑内铁蓄积的原因及其铁的氧化状态尚不清楚。本研究探讨了 PS 对大鼠脑内低分子铁库（LMWIP）的影响。结果表明：（1）PS 可显著增加大鼠大脑皮质、海马和纹状体中的 LMWIP；（2）PS 导致锥体细胞排列紊乱，CA1 和 CA2 神经元层减少；（3）PS 暴露可显著降低大鼠皮质和海马中铁蛋白（Fn）和热休克蛋白 72（HP）的表达；（4）PS 可降低大鼠大脑皮质、海马和纹状体中超氧化物歧化酶、谷胱甘肽过氧化物酶和谷胱甘肽水平，增加丙二醛水平。这些结果表明，PS 可显著增加 LMWIP，其可能与 PS 诱导的 Fn、HP 表达降低，进而导致铁储存和利用减少有关，而 LMWIP 的扩张又可能导致氧化损伤加重。
