Dilshara Matharage Gayani, Lee Kyoung-Tae, Lee Chang-Min, Choi Yung Hyun, Lee Hak-Ju, Choi Il-Whan, Kim Gi-Young
Department of Marine Life Sciences, Jeju National University, Jeju 690-756, Republic of Korea.
Division of Wood Chemistry & Microbiology Department of Forest Products, Korea Forest Research Institute, Republic of Korea.
Int Immunopharmacol. 2015 Jan;24(1):14-23. doi: 10.1016/j.intimp.2014.10.030. Epub 2014 Nov 8.
Microglia are main immune cells to exacerbate neural disorders in persistent overactivating. Therefore, it is a good strategy to regulate microglia for the treatment of neural disorders. In the present study, we isolated and characterized a novel compound, 5-O-isoferuloyl-2-deoxy-D-ribono-γ-lacton (5-DRL) from Clematis mandshurica, and evaluated its anti-inflammatory effect in lipopolysaccharide (LPS)-treated BV2 microglial cells. 5-DRL inhibited the expression of LPS-stimulated proinflammatory mediators such as nitric oxide (NO) and prostaglandin E2 (PGE2), as well as their regulatory genes inducible NO syntheses (iNOS) and cyclooxygenase-2 (COX-2). 5-DRL also downregulated the LPS-induced DNA-binding activity of nuclear factor-κB (NF-κB) through suppression of the nuclear translocation of the NF-κB subunits, p65 and p50. Consistent with the inhibition of iNOS and COX-2 via NF-κB activity with 5-DRL, an inhibitor of NF-κB, pyrrolidine dithiocarbamate (PDTC), also led to the suppression of LPS-induced iNOS and COX-2 expression. Additionally, 5-DRL corresponding with antioxidants, N-acetylcysteine (NAC) and glutathione (GSH), remarkably inhibited reactive oxygen species (ROS) generation. Both NAC and GSH, thus attenuated the expression of iNOS and COX-2 by suppressing NF-κB activation, indicating that 5-DRL suppresses LPS-induced iNOS and COX-2 expression through downregulation of the ROS-dependent NF-κB signaling pathway. The present study also indicated that 5-DRL suppresses NO and PGE2 production by inducing heme oxygenase-1 (HO-1) via nuclear factor erythroid 2-related factor 2 (Nrf2). Taken together, the present data indicate that 5-DRL attenuates the production of proinflammatory mediators such as NO and PGE2 as well as their regulatory genes in LPS-stimulated BV2 microglial cells by inhibiting ROS-dependent NF-κB activation and stimulating the Nrf2/HO-1 signal pathway. These data may be implicated in the application of 5-DRL in LPS-stimulated inflammatory disease.
小胶质细胞是在持续过度激活时加剧神经紊乱的主要免疫细胞。因此，调节小胶质细胞是治疗神经紊乱的一个好策略。在本研究中，我们从东北铁线莲中分离并鉴定了一种新型化合物5-O-异阿魏酰基-2-脱氧-D-核糖-γ-内酯（5-DRL），并评估了其在脂多糖（LPS）处理的BV2小胶质细胞中的抗炎作用。5-DRL抑制了LPS刺激的促炎介质如一氧化氮（NO）和前列腺素E2（PGE2）的表达，以及它们的调节基因诱导型NO合酶（iNOS）和环氧化酶-2（COX-2）的表达。5-DRL还通过抑制NF-κB亚基p65和p50的核转位下调了LPS诱导的核因子κB（NF-κB）的DNA结合活性。与5-DRL通过NF-κB活性抑制iNOS和COX-2一致，NF-κB抑制剂吡咯烷二硫代氨基甲酸盐（PDTC）也导致LPS诱导的iNOS和COX-2表达受到抑制。此外，与抗氧化剂N-乙酰半胱氨酸（NAC）和谷胱甘肽（GSH）相当的5-DRL显著抑制了活性氧（ROS）的产生。NAC和GSH均通过抑制NF-κB激活减弱了iNOS和COX-2的表达，表明5-DRL通过下调ROS依赖的NF-κB信号通路抑制LPS诱导的iNOS和COX-2表达。本研究还表明，5-DRL通过核因子红细胞2相关因子2（Nrf2）诱导血红素加氧酶-1（HO-1）来抑制NO和PGE2的产生。综上所述，目前的数据表明，5-DRL通过抑制ROS依赖的NF-κB激活并刺激Nrf2/HO-1信号通路，减弱了LPS刺激的BV2小胶质细胞中促炎介质如NO和PGE2及其调节基因的产生。这些数据可能与5-DRL在LPS刺激的炎症性疾病中的应用有关。
