Department of Stomatology, PLA Army General Hospital, Beijing 100700, China.
Department of Oncology, PLA Army General Hospital, Beijing 100700, China.
Biosci Rep. 2017 Nov 21;37(6). doi: 10.1042/BSR20170973. Print 2017 Dec 22.
Interleukin-12 (IL-12) is a proinflammatory cytokine, and its increased level correlates with the severity of periodontitis. However, its role in the pathogenesis of tooth periapical lesions is controversial and has not been completely clarified. The present study aimed to investigate whether IL-12 affects the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) in human periodontal ligament fibroblasts (hPDLFs). After treatment with IL-12 for different times, real-time PCR and Western blotting were used to determine the mRNA and protein levels of , MMP-3, , and , respectively. ELISA was applied to measure MMPs and TIMPs secretion production. The results indicated that IL-12 significantly increased the mRNA and protein expression levels of , and , but down-regulated and mRNA and protein expression in the hPDLFs. Furthermore, IL-12 (10 ng/ml) enhanced the secreted protein production of MMP-1, MMP-3, and MMP-13, and conversely lowered MMP-2 and MMP-9 secretion levels. However, IL-12 treatment did not exert a significant effect on the mRNA and protein levels of and and their secreted production. Additionally, IL-12 increased the phosphorylated levels of IκBα and nuclear factor-κB P65 (NF-κB P65), and promoted NF-κB P65 subunit nuclear translocation. Pretreatment with NF-κB inhibitor not only attenuated IL-12-induced IκBα and NF-κB P65 phosphorylation and inhibited NF-κB P65 subunit into nucleus, but also antagonized IL-12-mediated MMP-1, MMP-2, MMP-3, MMP-9, and MMP-13 expression in the hPDLFs. These findings indicate that NF-κB-dependent activation is possibly indispensable for IL-12-mediated MMP expression in hPDLFs.
白细胞介素-12（IL-12）是一种促炎细胞因子，其水平升高与牙周炎的严重程度相关。然而，其在牙髓根尖周病变发病机制中的作用存在争议，尚未完全阐明。本研究旨在探讨白细胞介素-12（IL-12）是否影响人牙周膜成纤维细胞（hPDLFs）中基质金属蛋白酶（MMPs）和金属蛋白酶组织抑制剂（TIMPs）的表达。用不同时间的 IL-12 处理后，采用实时 PCR 和 Western blot 分别检测 、MMP-3、 、和 ，酶联免疫吸附试验（ELISA）检测 MMPs 和 TIMPs 的分泌产物。结果表明，IL-12 可显著增加 hPDLFs 中 、和 的 mRNA 和蛋白表达水平，而 、和 的 mRNA 和蛋白表达水平则降低。此外，IL-12（10 ng/ml）增强了 MMP-1、MMP-3 和 MMP-13 的分泌蛋白产生，而降低了 MMP-2 和 MMP-9 的分泌水平。然而，IL-12 处理对 和 的 mRNA 和蛋白水平及其分泌产物无明显影响。此外，IL-12 增加了 IκBα 和核因子-κB P65（NF-κB P65）的磷酸化水平，并促进 NF-κB P65 亚基核转位。NF-κB 抑制剂预处理不仅减弱了 IL-12 诱导的 IκBα 和 NF-κB P65 磷酸化，并抑制了 NF-κB P65 亚基入核，还拮抗了 IL-12 介导的 hPDLFs 中 MMP-1、MMP-2、MMP-3、MMP-9 和 MMP-13 的表达。这些发现表明，NF-κB 依赖性激活可能是 IL-12 介导的 hPDLFs 中 MMP 表达所必需的。
