Department of Genetic Engineering, Sungkyunkwan University, Suwon 16419, Korea.
Basic Research & Innovation Division, R&D Center, Amorepacific Corporation, Yongin 17074, Korea.
Int J Mol Sci. 2018 Jun 21;19(7):1828. doi: 10.3390/ijms19071828.
8-Hydroxydaidzein (8-HD) is a daidzein metabolite isolated from soybeans. This compound has been studied for its anti-proliferation, depigmentation, and antioxidant activities. However, the anti-inflammatory activities of 8-HD are not well-understood. Through its antioxidant effects in ABTS and DPPH assays, 8-HD reduces the production of sodium nitroprusside (SNP)-induced radical oxygen species (ROS). By triggering various Toll-like receptors (TLRs), 8-HD suppresses the inflammatory mediator nitric oxide (NO) without cytotoxicity. We examined the regulatory mechanism of 8-HD in lipopolysaccharide (LPS)-induced conditions. We found that 8-HD diminishes inflammatory gene expression (e.g., inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, and tumor necrosis factor (TNF)-α) by regulating the transcriptional activities of nuclear factor (NF)-κB and activator protein 1 (AP-1). To find the potential targets of 8-HD, signaling pathways were investigated by immunoblotting analyses. These analyses revealed that 8-HD inhibits the activation of TAK1 and that phosphorylated levels of downstream molecules decrease in sequence. Together, our results demonstrate the antioxidant and anti-inflammatory actions of 8-HD and suggest its potential use in cosmetics or anti-inflammatory drugs.
8-羟基大豆苷元（8-HD）是从大豆中分离出的大豆苷元代谢物。该化合物因其抗增殖、脱色和抗氧化活性而受到研究。然而，8-HD 的抗炎活性尚未得到很好的理解。通过 ABTS 和 DPPH 测定中的抗氧化作用，8-HD 减少了硝普钠（SNP）诱导的活性氧（ROS）的产生。通过触发各种 Toll 样受体（TLR），8-HD 在没有细胞毒性的情况下抑制了一氧化氮（NO）等炎症介质的产生。我们研究了 8-HD 在脂多糖（LPS）诱导条件下的调节机制。我们发现 8-HD 通过调节核因子（NF）-κB 和激活蛋白 1（AP-1）的转录活性，降低了炎症基因的表达（例如诱导型一氧化氮合酶（iNOS）、环氧化酶（COX）-2 和肿瘤坏死因子（TNF）-α）。为了找到 8-HD 的潜在靶点，通过免疫印迹分析研究了信号通路。这些分析表明，8-HD 抑制了 TAK1 的激活，并且下游分子的磷酸化水平依次降低。总之，我们的结果表明 8-HD 具有抗氧化和抗炎作用，并表明其在化妆品或抗炎药物中的潜在用途。
