Department of Nephrology, Yijishan Hospital of Wannan Medical College, # 92 Zheshan Road, Wuhu, 241002, Anhui Province, People's Republic of China.
Medical Emergency Center, #158 Yueming Road, Baoshan District, Shanghai, 201900, People's Republic of China.
Inflamm Res. 2020 Apr;69(4):375-383. doi: 10.1007/s00011-019-01313-0. Epub 2020 Mar 7.
The currently available anti-inflammatory drugs often cause diverse side effects with long-term use. Exploring anti-inflammatory drugs with better efficacy and lower toxicity presents an ongoing challenge. Aloperine is an alkaloid extracted from the leaves and seeds of Sophora alopecuroides L. However, the anti-inflammatory effects of Aloperine have not been fully elucidated. This study aimed to investigate whether Aloperine suppresses lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 macrophages.
RAW264.7 macrophages were stimulated with LPS (1 μg/mL) in the presence or absence of Aloperine (50 and 100 μM). mRNA expression was measured by real-time PCR, and protein expression was assessed by western blot analysis. The secretion of pro-inflammatory cytokines was measured by ELISA. The levels of nitric oxide (NO) and reactive oxygen species (ROS) were measured by staining. The transcriptional activity of NF-κB was assayed by a luciferase activity assay.
The results proved that Aloperine inhibited the expression of LPS-induced pro-inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-17A (IL-17A)] in macrophages. Treatment with Aloperine inhibited NO production through suppressing inducible nitric oxide synthase (iNOS) expression and the secretion of prostaglandin E (PGE) by inhibiting cyclooxygenase 2 (COX-2) expression. Aloperine prevented LPS-induced oxidative stress by reducing the generation of ROS. Furthermore, aloperine significantly reduced Toll-like receptor 4 (TLR4) and myeloid differentiation factor (Myd-88) levels and prevented the nuclear translocation of nuclear factor-κB (NF-κB) in LPS-treated macrophages.
Taken together, our findings show that Aloperine could suppress LPS-induced macrophage activation by inhibiting the TLR4/Myd-88/NF-κB pathway.
目前可用的抗炎药物长期使用常常会引起多种副作用。探索疗效更好、毒性更低的抗炎药物一直是一个挑战。荷叶碱是从槐叶中提取的一种生物碱。然而，荷叶碱的抗炎作用尚未完全阐明。本研究旨在探讨荷叶碱是否抑制脂多糖（LPS）诱导的 RAW264.7 巨噬细胞炎症反应。
用 LPS（1μg/ml）刺激 RAW264.7 巨噬细胞，同时存在或不存在荷叶碱（50 和 100μM）。通过实时 PCR 测量 mRNA 表达，通过 Western blot 分析评估蛋白表达。通过 ELISA 测量促炎细胞因子的分泌。通过染色测量一氧化氮（NO）和活性氧（ROS）的水平。通过荧光素酶活性测定测定 NF-κB 的转录活性。
结果证明荷叶碱抑制了 LPS 诱导的巨噬细胞中促炎细胞因子[肿瘤坏死因子-α（TNF-α）、白细胞介素-6（IL-6）和白细胞介素-17A（IL-17A）]的表达。荷叶碱通过抑制诱导型一氧化氮合酶（iNOS）表达和抑制前列腺素 E（PGE）的分泌来抑制环氧化酶 2（COX-2）的表达，从而抑制 NO 的产生。荷叶碱通过减少 ROS 的产生来防止 LPS 诱导的氧化应激。此外，荷叶碱显著降低 TLR4 和髓样分化因子（Myd-88）水平，并防止 LPS 处理的巨噬细胞中核因子-κB（NF-κB）的核转位。
综上所述，我们的研究结果表明，荷叶碱可以通过抑制 TLR4/Myd-88/NF-κB 通路抑制 LPS 诱导的巨噬细胞激活。
