Bae Won-Jung, Shin Mee-Ran, Kang Soo-Kyung, Kim Jun-Yeol, Lee Sang-Cheon, Kim Eun-Cheol
Department of Oral and Maxillofacial Pathology, Research Center for Tooth and Periodontal Regeneration (MRC), School of Dentistry, Kyung Hee University, Seoul, Republic of Korea.
Department of Prosthodontics, Dongatn Sacred Heart Hospital, Hallym University, Dongtan, South Korea.
J Cell Biochem. 2015 Jul;116(7):1241-55. doi: 10.1002/jcb.25078.
Recent reports suggest that hypoxia inducible factor-2α (HIF-2α) is a key regulator of osteoarthritis cartilage destruction. However, the precise role of HIF-2α in the inflammatory response and osteoclast differentiation remains unclear. The purpose of this study was to investigate the effect of HIF-2α on inflammatory cytokines, extracellular matrix (ECM) destruction enzymes, and osteoclastic differentiation in nicotine and lipopolysaccharide (LPS)-stimulated human periodontal ligament cells (PDLCs). HIF-2α was upregulated in chronically inflamed PDLCs of periodontitis patients, and in nicotine- and LPS-exposed PDLC in dose- and time-dependent manners. HIF-2α inhibitor and HIF-2α siRNA attenuated the nicotine- and LPS- induced production of NO and PGE2 , upregulation of iNOS, COX-2, pro-inflammatory cytokines (IL-1β, TNF-α, IL-1β, IL-6, IL-8, IL-10, IL-11, and IL-17), and matrix metalloproteinases (MMPs; MMP-1, -8, -13, -2 and -9), and reversed the effect on TIMPs (TIMP-1 and -2) in PDLCs. The conditioned medium produced by nicotine and LPS-treated PDLCs increased the number of TRAP-stained osteoclasts, TRAP activity and osteoclast-specific genes, which has been blocked by HIF-2α inhibition and silencing. HIF-2α inhibitor and HIF-2α siRNA inhibited the effects of nicotine and LPS on the activation of Akt, JAK2 and STAT3, ERK and JNK MAPK, nuclear factor-κB, c-Jun, and c-Fos. Taken together, this study is the first to demonstrate that HIF-2α inhibition exhibits anti-inflammatory activity through the inhibition of inflammatory cytokines and impairment of ECM destruction, as well as blocking of osteoclastic differentiation in a nicotine- and periodontopathogen-stimulated PDLCs model. Thus, HIF-2α inhibition may be a novel molecular target for therapeutic approaches in periodontitis.
最近的报告表明，缺氧诱导因子-2α（HIF-2α）是骨关节炎软骨破坏的关键调节因子。然而，HIF-2α在炎症反应和破骨细胞分化中的确切作用仍不清楚。本研究的目的是探讨HIF-2α对尼古丁和脂多糖（LPS）刺激的人牙周膜细胞（PDLCs）中炎性细胞因子、细胞外基质（ECM）破坏酶和破骨细胞分化的影响。HIF-2α在牙周炎患者慢性炎症的PDLCs中上调，并在尼古丁和LPS暴露的PDLCs中呈剂量和时间依赖性上调。HIF-2α抑制剂和HIF-2α siRNA减弱了尼古丁和LPS诱导的NO和PGE2的产生、iNOS、COX-2、促炎细胞因子（IL-1β、TNF-α、IL-1β、IL-6、IL-8、IL-10、IL-11和IL-17）以及基质金属蛋白酶（MMPs；MMP-1、-8、-13、-2和-9）的上调，并逆转了对PDLCs中组织金属蛋白酶抑制剂（TIMPs；TIMP-1和-2）的影响。尼古丁和LPS处理的PDLCs产生的条件培养基增加了抗酒石酸酸性磷酸酶（TRAP）染色的破骨细胞数量、TRAP活性和破骨细胞特异性基因，这已被HIF-2α抑制和沉默所阻断。HIF-2α抑制剂和HIF-2α siRNA抑制了尼古丁和LPS对Akt、JAK2和STAT3、ERK和JNK丝裂原活化蛋白激酶（MAPK）、核因子κB、c-Jun和c-Fos激活的影响。综上所述，本研究首次证明，在尼古丁和牙周病原体刺激的PDLCs模型中，HIF-2α抑制通过抑制炎性细胞因子和损害ECM破坏以及阻断破骨细胞分化而表现出抗炎活性。因此，HIF-2α抑制可能是牙周炎治疗方法的一个新的分子靶点。
