Jung Hyo Young, Yoo Dae Young, Kim Jong Whi, Kwon Hyun Jung, Lee Kwon Young, Choi Jung Hoon, Kim Dae Won, Chung Jin Young, Yoon Yeo Sung, Hwang In Koo
Department of Anatomy and Cell Biology, College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, Seoul 08826, Republic of Korea.
Department of Biochemistry and Molecular Biology, Research Institute of Oral Sciences, College of Dentistry, Gangneung‑Wonju National University, Gangneung, Gangwon 25457, Republic of Korea.
Mol Med Rep. 2017 Jun;15(6):4333-4337. doi: 10.3892/mmr.2017.6512. Epub 2017 Apr 26.
Cyclooxygenase-2 (COX-2) is a known inducible inflammatory mediator. COX-2 is constitutively expressed in the hippocampus and may regulate synaptic plasticity. The present study investigated the age‑associated alterations in white blood cell counts and hippocampal COX‑2 expression in healthy mice using immunohistochemical and western blot analyses at 1 month postnatal (PM1), PM3, PM6, PM12 and PM24. White blood cell counts were significantly decreased in the PM24 group when compared with the PM1 group. In addition, lymphocyte counts were decreased in the PM24 group when compared with all other groups. By contrast, monocyte, neutrophil and eosinophil counts were increased in the PM24 group; however, this did not reach statistical significance. COX‑2 expression was identified in the granule cells of the dentate gyrus and in the pyramidal cells of the hippocampal CA2/3 region. COX‑2 immunoreactivity was maintained until PM18, however, the levels significantly decreased by PM24. These results suggest that, despite alterations in the differential white blood cell counts, the significant decrease in constitutive COX‑2 expression in the hippocampus may be associated with degenerative age-associated alterations in synaptic plasticity in the hippocampus.
环氧化酶-2（COX-2）是一种已知的诱导性炎症介质。COX-2在海马体中持续表达，并可能调节突触可塑性。本研究在出生后1个月（PM1）、PM3、PM6、PM12和PM24时，通过免疫组织化学和蛋白质印迹分析，研究了健康小鼠白细胞计数和海马体COX-2表达与年龄相关的变化。与PM1组相比，PM24组的白细胞计数显著降低。此外，与所有其他组相比，PM24组的淋巴细胞计数降低。相比之下，PM24组的单核细胞、中性粒细胞和嗜酸性粒细胞计数增加；然而，这未达到统计学意义。在齿状回的颗粒细胞和海马体CA2/3区域的锥体细胞中鉴定出COX-2表达。COX-2免疫反应性一直维持到PM18，但到PM24时水平显著降低。这些结果表明，尽管白细胞分类计数发生了变化，但海马体中组成型COX-2表达的显著降低可能与海马体中与年龄相关的突触可塑性退行性变化有关。
