中国神经再生研究(英文版) ›› 2023, Vol. 18 ›› Issue (11): 2497-2503.doi: 10.4103/1673-5374.371379

• 原著:退行性病与再生 • 上一篇    下一篇

长期的射频电磁场通过调节小胶质细胞功能减轻阿尔茨海默病小鼠的认知功能障碍

  

  • 出版日期:2023-11-15 发布日期:2023-05-05
  • 基金资助:
    韩国政府(MSIT)资助的信息和通信技术规划与评估研究所(IITP)支持

Long-term radiofrequency electromagnetic fields exposure attenuates cognitive dysfunction in 5×FAD mice by regulating microglial function

Yeonghoon Son1, #, Hye-Jin Park1, #, Ye Ji Jeong1, #, Hyung-Do Choi2, Nam Kim3, Hae-June Lee1, *   

  1. 1Division of Radiation Biomedical Research, Korea Institute of Radiological & Medical Sciences, Seoul, Korea; 2Department of EMF Research Team, Radio and Broadcasting Technology Laboratory, Electronics and Telecommunications Research Institute, Daejon, Korea; 3School of Electrical and Computer Engineering, Chungbuk National University, Cheongju, Korea
  • Online:2023-11-15 Published:2023-05-05
  • Contact: Hae-June Lee, DVM, PhD, hjlee@kirams.re.kr.
  • Supported by:
    This work was supported by Institute of Information & Communications Technology Planning & Evaluation (IITP) grant funded by Korea government (MSIT), Nos. 2017-0-00961 and 2019-0-00102 (to HDC).

摘要:

作者所在课题组既往研究发现,长期的射频电磁场(RF-EMFs)可减少严重晚期阿尔茨海默病(AD)小鼠淀粉样β蛋白沉积。为了解其干预效果是否与调节小胶质细胞的激活有关,实验分析了阿尔茨海默病模型5×FAD小鼠小胶质细胞的基因表达谱和海马小胶质细胞功能。6月龄的5×FAD小鼠被随机分为假暴露组和RF-EMF组,然后将其暴露在1950MHz的RF-EMF中,比吸收率(SAR)为5.0W/kg,2小时/天,5天/周,持续6个月。行为学测试(物体识别和Y型迷宫测试)和脑组织中淀粉样前体蛋白-淀粉样β蛋白代谢的分子和组织病理学分析结果显示,RF-EMFs暴露6个月可以改善5×FAD小鼠认知障碍和淀粉样β蛋白的沉积。与假暴露组相比,RF-EMFs暴露的5×FAD小鼠海马Iba1(小胶质细胞标志物)和CSF1R(调节小胶质细胞增殖)的表达水平明显降低。随后分析了RF-EMFs暴露组和CSF1R抑制剂PLX3397干预组小胶质细胞增生和小胶质细胞功能相关基因的表达水平。RF-EMFs和PLX3397均抑制了与小胶质增生(Csf1r,CD68和Ccl6)和促炎症细胞因子(IL-1β)相关的基因水平。值得注意的是,与小胶质功能有关的基因,包括Trem2,Fcgr1a,Ctss和Spi,在长期的RF-EMF暴露和PLX3397干预后表达水平下降,这也是在PLX3397对小胶质的抑制中观察到的。这些结果表明,RF-EMF可通过抑制淀粉样β蛋白沉积诱导的小胶质细胞及其关键调节因子CSF1R改善淀粉样β蛋白病理学改变和认知障碍。

https://orcid.org/0000-0002-7743-0151 (Hae-June Lee)

Abstract: We have previously found that long-term effects of exposure to radiofrequency electromagnetic fields in 5×FAD mice with severe late-stage Alzheimer’s disease reduced both amyloid-β deposition and glial activation, including microglia. To examine whether this therapeutic effect is due to the regulation of activated microglia, we analyzed microglial gene expression profiles and the existence of microglia in the brain in this study. 5×FAD mice at the age of 1.5 months were assigned to sham- and radiofrequency electromagnetic fields-exposed groups and then animals were exposed to 1950 MHz radiofrequency electromagnetic fields at a specific absorption rate of 5 W/kg for 2 hours/day and 5 days/week for 6 months. We conducted behavioral tests including the object recognition and Y-maze tests and molecular and histopathological analysis of amyloid precursor protein/amyloid-beta metabolism in brain tissue. We confirmed that radiofrequency electromagnetic field exposure for 6 months ameliorated cognitive impairment and amyloid-β deposition. The expression levels of Iba1 (pan-microglial marker) and colony-stimulating factor 1 receptor (CSF1R; regulates microglial proliferation) in the hippocampus in 5×FAD mice treated with radiofrequency electromagnetic fields were significantly reduced compared with those of the sham-exposed group. Subsequently, we analyzed the expression levels of genes related to microgliosis and microglial function in the radiofrequency electromagnetic fields-exposed group compared to those of a CSF1R inhibitor (PLX3397)-treated group. Both radiofrequency electromagnetic fields and PLX3397 suppressed the levels of genes related to microgliosis (Csf1r, CD68, and Ccl6) and pro-inflammatory cytokine interleukin-1β. Notably, the expression levels of genes related to microglial function, including Trem2, Fcgr1a, Ctss, and Spi1, were decreased after long-term radiofrequency electromagnetic field exposure, which was also observed in response to microglial suppression by PLX3397. These results showed that radiofrequency electromagnetic fields ameliorated amyloid-β pathology and cognitive impairment by suppressing amyloid-β deposition-induced microgliosis and their key regulator, CSF1R.

Key words: 5×FAD, Alzheimer’s disease, CSF1R,  , long term exposure, microglial function, neuroinflammation, radiofrequency electromagnetic fields, therapeutic effect