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

• Published in: Inflammation research 2015-07, Vol.64 (7), p.487-495
• Main Authors: Wang, Fa-Xiang, Liu, Shi-Yong, Zheng, Xin, Chen, Xin, Lu, Lin-Xiang, Chen, Bin, Xiong, Xiao-yi, Shu, Hai-Feng, Yang, Qing-Wu, Yang, Hui
• Format: Article
• Language: English
• Subjects: Allergology; Animals; Astrocytes - drug effects; Astrocytes - metabolism; Biomedical and Life Sciences; Biomedicine; Brain Chemistry - genetics; CA1 Region, Hippocampal - drug effects; CA1 Region, Hippocampal - metabolism; Dentate Gyrus - drug effects; Dentate Gyrus - metabolism; Dermatology; Epilepsy, Temporal Lobe - chemically induced; Epilepsy, Temporal Lobe - genetics; Excitatory Amino Acid Agonists; Immunohistochemistry; Immunology; Injections, Intraventricular; Kainic Acid; Mice; Mice, Inbred C57BL; Microglia - drug effects; Microglia - metabolism; Neurology; Neurons - drug effects; Neurons - metabolism; Original Research Paper; Pharmacology/Toxicology; Polymerase Chain Reaction; Rheumatology; RNA, Messenger - biosynthesis; RNA, Messenger - genetics; Seizures - chemically induced; Seizures - genetics; Toll-Like Receptor 1 - biosynthesis; Toll-Like Receptor 1 - genetics; Up-Regulation - drug effects
• ISSN: 1023-3830; 1420-908X
• DOI: 10.1007/s00011-015-0828-7

Objective 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. Methods 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. Results 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. Significance 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.