TITLE:
Upregulated genes in toll-like receptor (TLR) signaling pathway in periodontitis-affected gingival tissues
AUTHORS:
Daisuke Abe, Takehiko Kubota, Toshiya Morozumi, Hiromasa Yoshie
KEYWORDS:
TLR Signaling Pathway; Gene Expression; Microarray; qRT-PCR
JOURNAL NAME:
Open Journal of Stomatology,
Vol.4 No.1,
January
15,
2014
ABSTRACT: Toll-like receptor (TLR) signaling is thought to be
one of the most important pathways initiating periodontitis onset. We have
previously reported that the TLR signaling pathway is upregulated in periodontitis-affected gingival tissues by microarray pathway frequency analysis. The aim
of the present study was to quantitatively analyze specific upregulated genes in
the TLR signaling pathway, as compared to healthy controls. Healthy and
periodontitis-affected gingival tissues were
taken from distinct sites of 3 patients with severe chronic
periodontitis. Total RNAs from 6 gingival tissue samples were used for microarray.
Samples were taken from 14 chronic periodontitis patients and 14 healthy
individuals for quantitative reverse transcription
real-time polymerase chain reaction (qRT-PCR) analysis. Data-mining
analyses, such as pathway analyses, were performed and significant biological
pathways in periodontitis were identified. In addition, qRT-PCR analysis was
performed for 5 genes—cluster of differentiation 14 (CD14), lymphocyte antigen
96 (MD-2), interleukin-1 beta (IL-1β),
interleukin 8 (IL-8), and chemokine ligand 9 (CXCL-9), which are associated
with TLR signaling, in order to confirm the
results of pathway analysis. qRT-PCR verified that the transcripts for
5 genes in the TLR signaling pathway were significantly upregulated (MD-2 p = 0.0082, CD14 p = 0.0322, IL-1β p = 0.0126, IL-8 p = 0.0438, CXCL-9 p = 0.0325),
which was consistent with pathway analyses. We confirmed upregulated MD-2 gene expression levels and associated TLR
pathway gene expression, including CD14, IL-1β, IL-8 and CXCL-9, in periodontitis-affected gingival tissues, as
compared with healthy controls.