目的 · 探讨 3,3’- 二吲哚基甲烷（3,3’-diindolylmethane，DIM）对脂多糖（lipopolysaccharide，LPS）诱导的人牙周膜细胞
（human periodontal ligament cells，hPDLCs）分泌炎症因子的影响，并初步探讨其相关作用机制。方法 · 分离培养 hPDLCs，CCK-8 法
测定 DIM 对 hPDLCs 增殖的影响，检测 DIM 毒性浓度范围。将 hPDLCs 分为 4 组：空白组加入不含 LPS 和 DIM 的无血清 DMEM；
LPS 组仅加入含 LPS（终浓度为 10 μg/mL）的无血清 DMEM；低浓度组含 10 μg/mL LPS+6.25 μmol/L DIM；高浓度组含 10 μg/mL
LPS+12.50 μmol/L DIM。培养 12 h，酶联免疫吸附试验检测各组上清液中 TNF-α、IL-1β 和 IL-6 浓度，Western blotting 检测 hPDLCs
内丝裂原活化蛋白激酶（mitogen-activated protein kinase，MAPK）和核因子 κB（nuclear factor κB，NF-κB）信号通路中蛋白的变
化。结果 · DIM 在 50 μmol/L 范围内时细胞活力不受影响（P>0.05）。低浓度和高浓度 DIM 均抑制 LPS 刺激下 hPDLCs 分泌炎症因子
TNF-α、IL-1β 和 IL-6（P<0.05），抑制效果随 DIM 的浓度升高而增强。DIM 可显著抑制 LPS 激活 NF-κB 信号通路。结论 · DIM 可能
通过抑制 NF-κB 信号通路的激活，抑制 LPS 诱导的 hPDLCs 分泌促炎因子 TNF-α、IL-1β 和 IL-6。

Objective · To investigate the effect of 3,3’-diindolylmethane (DIM) on the expression of inflammatory cytokines in human periodontal ligament cells (hPDLCs) induced by lipopolysaccharide (LPS) and to study the related mechanism. Methods · hPDLCs were isolated and cultured, and
CCK-8 method was used to detect the effect of DIM on the proliferation of hPDLCs. hPDLCs were randomly divided into 4 groups: blank group (without
LPS and DIM), LPS group (10 μg/mL LPS), 10 μg/mL LPS+6.25 μg/mL DIM, 10 μg/mL LPS+12.50 μg/mL DIM. The cells of all groups were cultured
for 12 h. The protein levels of TNF-α, IL-1β and IL-6 in supernatant were detected by enzyme linked immunosorbent assay. The change of mitogenactivated protein kinase (MAPK) and nuclear factor κB (NF-κB) signaling pathways were detected by Western blotting. Results · The cell viability was
not affected when the DIM concentration was less than 50 μmol/L (P>0.05). DIM at 6.25 and 12.50 μg/mL reduced the LPS-induced expression of TNF-α,
IL-1β and IL-6 at protein levels (P<0.05). DIM inhibited the activation of the NF-κB signaling pathway. Conclusion · DIM can reduce the LPS-induced
inflammatory cytokine expression in hPDLCs via restraining the activation of the NF-κB signaling pathway.