Department of Restorative Dentistry, School of Dentistry, University of São Paulo, São Paulo, Brazil.
Department of Restorative Dentistry, School of Dentistry, University of São Paulo, São Paulo, Brazil.
J Endod. 2020 Mar;46(3):413-418. doi: 10.1016/j.joen.2019.12.001. Epub 2020 Jan 25.
Root canal treatment of immature necrotic teeth is a major challenge in current endodontics. The effect of inflammatory mediators, such as prostaglandin, on the modulation of stem cells of the apical papilla (SCAP) is not completely understood. The aim of this study was to investigate the role of prostaglandin E (PGE) on SCAP activation by Escherichia coli lipopolysaccharide (LPS) in vitro.
SCAP cultures were established and characterized. Increasing concentrations of lipopolysaccharide (0.1-10 μg/mL) were used to investigate cyclooxygenase-2 (COX-2/PTGS2) and PGE receptors (EP1-4) gene expression. Then, SCAP were treated with a COX-2 inhibitor (indomethacin) before treatment with different concentrations of LPS. The levels of the chemokine CCL2/monocyte chemoattractant protein 1 and interleukin (IL)-6 were detected in cell supernatants (24 hours) by enzyme-linked immunosorbent assay. Data analysis was performed using analysis of variance followed by the Tukey post test.
The expression of COX-2 was up-regulated in the group treated with LPS at 1μg/mL compared with that in the control group. EP1-4 were detected in all experimental conditions at similar levels. SCAP treated with indomethacin presented a down-regulation in the production of LPS-induced CCL2 and the secretion of IL-6.
SCAP showed increased COX-2 (PTGS2) gene expression induced by LPS and a PGE-dependent production of IL-6 and CCL2.
目前牙髓学的一个主要挑战是对未成熟坏死牙进行根管治疗。关于炎性介质（如前列腺素）对根尖乳头干细胞（SCAP）的调节作用还不完全清楚。本研究旨在探讨前列腺素 E（PGE）在大肠杆菌脂多糖（LPS）体外诱导 SCAP 激活中的作用。
建立和鉴定 SCAP 培养物。用不同浓度的脂多糖（0.1-10μg/mL）来研究环氧化酶-2（COX-2/PTGS2）和 PGE 受体（EP1-4）基因表达。然后，在用不同浓度 LPS 处理之前，用 COX-2 抑制剂（吲哚美辛）处理 SCAP。通过酶联免疫吸附试验检测细胞上清液（24 小时）中趋化因子 CCL2/单核细胞趋化蛋白 1 和白细胞介素（IL）-6 的水平。采用方差分析，随后进行 Tukey 事后检验进行数据分析。
与对照组相比，用 1μg/mL LPS 处理的组 COX-2 的表达上调。在所有实验条件下均检测到 EP1-4。用吲哚美辛处理的 SCAP 中 LPS 诱导的 CCL2 产生和 IL-6 分泌下调。
SCAP 显示 LPS 诱导的 COX-2（PTGS2）基因表达增加，并依赖 PGE 产生 IL-6 和 CCL2。
