Kim Yeon Ju, Park Sung Yun, Koh Young Jun, Lee Ju-Hee
Department of Medical Biotechnology, Dongguk University, Seoul 04620, Korea.
College of Korean Medicine, Dongguk University, Goyang 10326, Korea.
Plants (Basel). 2021 Apr 2;10(4):688. doi: 10.3390/plants10040688.
For centuries, (FLL; the fruit of Aiton or Thunb.) has been commonly used in traditional Chinese medicine for treating hepatitis and aging-related symptoms and in traditional Korean medicine to detoxify kidneys and the liver. Pharmacological research has shown FLL has antioxidant, anti-inflammatory, anticancer, anti-osteoporosis, and hepatoprotective activities. This study was undertaken to investigate the effects of FLL extract (FLLE) on neuroinflammation. After setting a non-toxic concentration using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide] assay data, we investigated the effects of FLLE using Western blotting, cell migration, enzyme-linked immunosorbent assay, a nitric oxide (NO) assay, and immunofluorescence staining in lipopolysaccharide (LPS)-stimulated murine BV2 microglial cells. FLLE was non-toxic to BV2 cells up to a concentration of 500 μg/mL and concentration-dependently inhibited the production of NO and prostaglandin E and the protein levels of inducible nitric oxide synthase and cyclooxygenase-2 under LPS-induced inflammatory conditions. It also inhibited the secretion of the inflammatory cytokines tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Furthermore, FLLE pretreatment attenuated LPS-induced increases of CD68 (a marker of microglia activation) and suppressed the activation of mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) signaling pathways in LPS-stimulated BV2 cells, and significantly increased heme oxygenase (HO)-1 levels. FLLE also reduced the LPS-induced increase in the migratory ability of BV2 cells and the phosphorylation of vascular endothelial growth factor receptor 1. Collectively, FLLE effectively inhibited inflammatory response by suppressing the MAPK and NF-κB signaling pathways and inducing HO-1 in LPS-stimulated BV2 microglial cells. Our findings provide a scientific basis for further study of FLL as a candidate for preventing or alleviating neuroinflammation.
几个世纪以来，（FLL；艾顿或图恩贝里的果实）在传统中医中一直被普遍用于治疗肝炎和与衰老相关的症状，在传统韩医中用于肾脏和肝脏的解毒。药理学研究表明，FLL具有抗氧化、抗炎、抗癌、抗骨质疏松和肝脏保护活性。本研究旨在探讨FLL提取物（FLLE）对神经炎症的影响。利用MTT [3-(4,5-二甲基噻唑-2-基)-2,5-二苯基溴化四氮唑] 检测数据设定无毒浓度后，我们在脂多糖（LPS）刺激的小鼠BV2小胶质细胞中，通过蛋白质免疫印迹法、细胞迁移实验、酶联免疫吸附测定、一氧化氮（NO）检测和免疫荧光染色，研究了FLLE的作用。FLLE在浓度高达500 μg/mL时对BV2细胞无毒，并在LPS诱导的炎症条件下，浓度依赖性地抑制NO和前列腺素E的产生以及诱导型一氧化氮合酶和环氧化酶-2的蛋白水平。它还抑制炎性细胞因子肿瘤坏死因子-α（TNF-α）和白细胞介素-6（IL-6）的分泌。此外，FLLE预处理减弱了LPS诱导的CD68（小胶质细胞活化标志物）增加，并抑制了LPS刺激的BV2细胞中丝裂原活化蛋白激酶（MAPKs）和核因子-κB（NF-κB）信号通路的激活，并显著增加血红素加氧酶（HO）-1水平。FLLE还降低了LPS诱导的BV2细胞迁移能力增加以及血管内皮生长因子受体1的磷酸化。总体而言，FLLE通过抑制MAPK和NF-κB信号通路并在LPS刺激的BV2小胶质细胞中诱导HO-1，有效抑制了炎症反应。我们的研究结果为进一步研究FLL作为预防或减轻神经炎症的候选药物提供了科学依据。
