Inflammation Research

, Volume 64, Issue 7, pp 487–495 | Cite as

TLR1 expression in mouse brain was increased in a KA-induced seizure model

  • Fa-Xiang Wang
  • Shi-Yong Liu
  • Xin Zheng
  • Xin Chen
  • Lin-Xiang Lu
  • Bin Chen
  • Xiao-yi Xiong
  • Hai-Feng Shu
  • Qing-Wu Yang
  • Hui Yang
Original Research Paper



Toll-like receptors (TLRs) that mediate inflammatory responses play an important role in epilepsy; however, whether TLR1 is also involved in epileptogenesis remains unclear. Thus, in this study, we investigated the extent and pattern of TLR1 expression in epileptic tissues.


One-hundred and thirty-two mice were intra-cerebroventricularly injected with PBS or kainic acid (KA) and were examined at 1, 3, 8 and 24 h. The expression pattern and distribution of TLR1 were examined by reverse-transcriptase polymerase chain reaction (RT-PCR), western blot analysis and immunohistochemistry staining.


The mRNA and protein levels of TLR1 were significantly upregulated in the hippocampus and temporal cortex of epileptic mice compared with those of controls. TLR1 expression was increased as early as 1 h following KA treatment and peaked at 8 and 24 h. Immunohistochemistry staining demonstrated that TLR1 was distributed in the CA1-3, dentate gyrus and hilus regions of the hippocampus and different cortical regions. Immunofluorescent staining further revealed that TLR1 was primarily expressed in the neurons, microglia, and astrocytes of epileptogenic tissue.


These results demonstrate that cortical and hippocampal sub-regional expression of TLR1 is altered during epileptogenesis in a time- and location-specific manner, suggesting a close association with the process of epilepsy.


Toll-like receptors TLR1 Status epilepticus Temporal lobe epilepsy 



This work was supported by the National Natural Science Foundation of China (No. 81070953, 81071043, 81371424, and 81371430).

Conflict of interest

None of the authors have any conflicts of interest to disclose. We also confirm that we have read the Journal’s position on issues related to ethical publication and affirm that this report is consistent with those guidelines.

Supplementary material

11_2015_828_MOESM1_ESM.jpg (402 kb)
Supplement Fig. 1. TLR1 mRNA expression in the hippocampus and temporal cortex following SE. A) Representative RT-PCR results demonstrating TLR1 mRNA expression in the hippocampus of PBS-treated mice and KA-induced mice following 1, 3, 8, and 24 h. The graph indicates that the mean OD value of TLR1 transiently increased from 1 to 24 h after the seizures. TLR1 (relative to GAPDH) mRNA quantification between PBS-treated and seizure mice from 1 to 24 h after seizures is presented. B) Representative band results demonstrating TLR1 mRNA expression in the temporal cortex of PBS-treated mice and KA-induced mice at 1, 3, 8, and 24 h. The graph indicates that the mean OD value of TLR1 transiently increased from 1 to 24 h after seizures. TLR1 (relative to GAPDH) mRNA ratios between PBS-treated and seizure mice at 1 to 24 h after seizures is presented. n = 8 for each subunit, **P < 0.01 vs PBS group; #P < 0.01 vs KA 8 h group. (JPEG 402 kb)
11_2015_828_MOESM2_ESM.jpg (265 kb)
Supplement Fig. 2. Fluorescent images of TLR1 in the temporal cortex of epileptic mice.A–C) TLR1 was primarily expressed in the cell bodies and dendrites of neurons (A; arrows) and was co-expressed with NeuN (B–C; arrows). D–I) TLR1 staining was also observed in the cytoplasm and end processes of astrocytes (D; arrow) and CD11b-positive microglia (G; arrow). TLR was expressed by GFAP-positive astrocytes (F; arrows) and CD11b-positive microglia (I; arrows). Scale bars = 25 μm. (JPEG 264 kb)


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Copyright information

© Springer Basel 2015

Authors and Affiliations

  • Fa-Xiang Wang
    • 1
  • Shi-Yong Liu
    • 1
  • Xin Zheng
    • 1
  • Xin Chen
    • 1
  • Lin-Xiang Lu
    • 1
  • Bin Chen
    • 1
  • Xiao-yi Xiong
    • 2
  • Hai-Feng Shu
    • 3
  • Qing-Wu Yang
    • 2
  • Hui Yang
    • 1
  1. 1.Department of Neurosurgery, Xinqiao HospitalThird Military Medical UniversityChongqingChina
  2. 2.Department of Neurology, Xinqiao HospitalThird Military Medical UniversityChongqingChina
  3. 3.Department of NeurosurgeryGeneral Hospital of the People’s Liberation Army Chengdu Military RegionSichuanChina

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