Guo Yong-Xian, Liu Liang, Yan Dong-Zhan, Guo Jian-Ping
Department of Orthopedics, The Second People's Hospital of Liaocheng, Affiliated Hospital of Taishan Medical University, Linqing, Shandong 252600, P.R. China.
Department II of Orthopedics, Linzi District People's Hospital, Zibo, Shandong 255400, P.R. China.
Mol Med Rep. 2017 Apr;15(4):2333-2338. doi: 10.3892/mmr.2017.6234. Epub 2017 Feb 22.
Osteoarthritis (OA) is an inflammatory disorder dealing with the focal degradation of articular cartilage. Oxidative stress and inflammation are the major events in OA. The present study aimed at identifying the mechanism of the potent antioxidant, plumbagin, in protecting against hydrogen peroxide (H2O2)‑induced chondrocyte oxidative stress and inflammatory signaling. Oxidative stress was determined by measuring reactive oxygen species, lipid peroxidation, non‑enzymic (glutathione; GSH) and enzymic antioxidant activities (GSH, glutathione S‑transferase, glutathione peroxidase, superoxide dismutase, catalase). Expression levels of nuclear factor (erythroid‑derived 2)‑like 2 (Nrf‑2), heme oxygenase 1 (HO‑1), NAD(P)H:quinone oxidoreductase 1 (NQO‑1), nuclear factor‑κB (NF‑κB), cyclooxygenase‑2 (COX‑2) and inducible NO synthase (iNOS) were determined by western blot analysis. Pro‑inflammatory cytokine expression levels were assessed using ELISA. Results from reactive oxygen species generation, lipid peroxidation content and antioxidant enzyme activities demonstrated that plumbagin significantly inhibited oxidative stress status in H2O2‑induced chondrocytes. In addition, plumbagin modulated transcription factors involved in redox and inflammation regulation, including NF‑κB and Nrf‑2, by nuclear expression. plumbagin enhanced antioxidant status by increasing the expression levels of Nrf‑2 target genes, including HO‑1 and NQO‑1. An anti‑inflammatory effect against chondrocyte‑induced inflammation was demonstrated by downregulating COX‑2, iNOS and pro‑inflammatory cytokine expression levels (tumor necrosis factor‑α, interleukin (IL)‑6 and IL‑8). The present study identified strong evidence for a protective role of plumbagin against H2O2-induced oxidative stress and inflammation in chondrocytes by modulating redox signaling transcription factors.
骨关节炎（OA）是一种涉及关节软骨局灶性降解的炎症性疾病。氧化应激和炎症是OA的主要发病机制。本研究旨在确定强效抗氧化剂白花丹醌在预防过氧化氢（H2O2）诱导的软骨细胞氧化应激和炎症信号传导中的作用机制。通过测量活性氧、脂质过氧化、非酶（谷胱甘肽；GSH）和酶抗氧化活性（GSH、谷胱甘肽S-转移酶、谷胱甘肽过氧化物酶、超氧化物歧化酶、过氧化氢酶）来确定氧化应激。通过蛋白质印迹分析确定核因子（红细胞衍生2）样2（Nrf-2）、血红素加氧酶1（HO-1）、NAD（P）H：醌氧化还原酶1（NQO-1）、核因子-κB（NF-κB）、环氧化酶-2（COX-2）和诱导型一氧化氮合酶（iNOS）的表达水平。使用酶联免疫吸附测定法评估促炎细胞因子的表达水平。活性氧生成、脂质过氧化含量和抗氧化酶活性的结果表明，白花丹醌显著抑制H2O2诱导的软骨细胞中的氧化应激状态。此外，白花丹醌通过核表达调节参与氧化还原和炎症调节的转录因子，包括NF-κB和Nrf-2。白花丹醌通过增加Nrf-2靶基因（包括HO-1和NQO-1）的表达水平来增强抗氧化状态。通过下调COX-2、iNOS和促炎细胞因子表达水平（肿瘤坏死因子-α、白细胞介素（IL）-6和IL-8）证明了对软骨细胞诱导的炎症具有抗炎作用。本研究通过调节氧化还原信号转录因子，为白花丹醌对H2O2诱导的软骨细胞氧化应激和炎症的保护作用提供了有力证据。
