| dc.description.abstract | This study seeks to quantitatively evaluate the expression of messenger RNA (mRNA)
of integrins alpha1, alfa4, alpha 5, alpha L, cytokines, and chemokines, from cells
present in the periapical interstitial fluid adjacent to teeth with root canal infection.
Twenty-two individuals needing endodontic treatment and referred to the School of
Dentistry of the Federal University of Minas Gerais (Belo Horizonte, MG, Brazil) were
selected. The samples were collected in 11 necrotic teeth and carriers of endodontic
infections and 11 healthy teeth needing endodontic treatment for prosthetic reasons.
After access surgery and before root canal system (RCS) cleaning and shaping
procedures (T0), immediately after cleaning and shaping the root canal system (T1),
in 7 (T2) and 14 days (T3) an endodontic sterilized paper point #20 was inserted into
the RCS, maintained for 2 min, and subsequently stored at -70°C. Real-Time PCR
microbiologically analyzed these samples to read the gene expression of microbial
rRNA 16S and fragments of the ITS region of the Fungus Candida species gDNA. After
RCS cleaning and shaping procedures, three sterilized absorbent paper cones were
inserted. Passively, the paper point exceeded the root apex by 2 mm and remained for
2 minutes. Samples were collected immediately after RCS cleaning and shaping, 7
and 14 days after the first session. The paper points have the 4 mm of their tip cut,
inserted in Eppendorf, and stored at - 70°C. This procedure extracted RNA from the
periapical interstitial fluid to characterize the expressions of the genes ITGA1, ITGA4,
ITGA5, ITGAL, IL-1β, TNF- α, IL-17A, IL-10, IFN-γ, CCL2/MCP-1, CCL5, CXCR4, ITS
using Real-Time PCR. The results showed that 16S mRNA expression levels
decreased after cleaning and modeling procedures and that Candida abundance was
incipient in the analyzed sample. Pro-inflammatory cytokines IL-1β and IL-17 showed
high expression levels against infection, significantly reduced after cleaning and
formatting procedures. TNF-α gene expression levels significantly increased in both
experimental and control groups. No significant difference was observed regarding the
gene expression of the cytokines IFN-γ, IL-10, CCL-2, and CCL-5 and the integrins
ITGAL and ITGA5. The gene expressions of ITGA1 and ITGA4 in the experimental
group were significantly reduced time-dependent. Finally, there was no significant
change in their macrophage markers (CD64) expression, while fibroblast markers
(S100A4) expression significantly increased in the control group. It was concluded that
microbial load and yeast abundance are positively correlated with the expression of
pro-inflammatory mediators and that endodontic therapy negatively impacts the
expression of pro-inflammatory mediators and integrins in periradicular tissues | |
