School of Pharmacy, Sungkyunkwan University, Suwon 16419, Korea.
College of Pharmacy, Chonnam National University, Gwangju 61186, Korea.
Biomolecules. 2019 Nov 20;9(12):755. doi: 10.3390/biom9120755.
Phytochemical investigation of the methanol (MeOH) extract of roots, known as "kudzu", combined with liquid chromatography/mass spectrometry (LC/MS)-based analysis, resulted in the identification of four norlignans (-), including three new norlignans, lobatamunsolides A-C (-), and five known isoflavonoids (-). The structures of the new compounds were elucidated by a combination of spectroscopic methods, including 1D and 2D nuclear magnetic resonance (NMR) and high resolution (HR)-electrospray ionization mass spectrometry (ESIMS), and their absolute configurations were determined by chemical reaction and quantum chemical electronic circular dichroism (ECD) calculations. The isolated compounds (-) were evaluated for their inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Compound displayed the strongest NO inhibitory effect and compound showed a weak effect. The potential mechanism of the effect of compound was investigated by analysis of its molecular docking on the active site of inducible nitric oxide synthase (iNOS), which showed the potential interactions of compound with key amino acid residues and the heme cofactor of iNOS. The mechanism as the inhibition of transcriptional iNOS protein expression was confirmed by western blotting experiments.
采用甲醇（MeOH）提取物对“葛”根进行植物化学研究，结合液相色谱/质谱（LC/MS）分析，鉴定出四种新的异落叶松脂素 A-C（-）和五种已知的异黄酮（-）。通过光谱方法，包括 1D 和 2D 核磁共振（NMR）和高分辨率（HR）电喷雾电离质谱（ESIMS），组合鉴定了新化合物的结构，并通过化学反应和量子化学电子圆二色性（ECD）计算确定了它们的绝对构型。对分离得到的化合物（-）进行了评估，以检测它们对脂多糖（LPS）刺激的 RAW 264.7 巨噬细胞中一氧化氮（NO）生成的抑制作用。化合物 表现出最强的 NO 抑制作用，而化合物 表现出较弱的作用。通过分析化合物 与诱导型一氧化氮合酶（iNOS）活性位点的分子对接，研究了化合物 作用的潜在机制，结果表明化合物 与 iNOS 的关键氨基酸残基和血红素辅因子具有潜在的相互作用。通过 Western blot 实验证实了抑制转录 iNOS 蛋白表达的机制。
