School of Pharmaceutical Sciences, Jilin University, Changchun 130021, China.
College of Basic Medical Sciences, Jilin University, Changchun 130021, China.
Molecules. 2021 Sep 20;26(18):5698. doi: 10.3390/molecules26185698.
Artemisinin (also known as Qinghaosu), an active component of the Qinghao extract, is widely used as antimalarial drug. Previous studies reveal that artemisinin and its derivatives also have effective anti-inflammatory and immunomodulatory properties, but the direct molecular target remains unknown. Recently, several reports mentioned that myeloid differentiation factor 2 (MD-2, also known as lymphocyte antigen 96) may be the endogenous target of artemisinin in the inhibition of lipopolysaccharide signaling. However, the exact interaction between artemisinin and MD-2 is still not fully understood. Here, experimental and computational methods were employed to elucidate the relationship between the artemisinin and its inhibition mechanism. Experimental results showed that artemether exhibit higher anti-inflammatory activity performance than artemisinin and artesunate. Molecular docking results showed that artemisinin, artesunate, and artemether had similar binding poses, and all complexes remained stable throughout the whole molecular dynamics simulations, whereas the binding of artemisinin and its derivatives to MD-2 decreased the TLR4(Toll-Like Receptor 4)/MD-2 stability. Moreover, artemether exhibited lower binding energy as compared to artemisinin and artesunate, which is in good agreement with the experimental results. Leu61, Leu78, and Ile117 are indeed key residues that contribute to the binding free energy. Binding free energy analysis further confirmed that hydrophobic interactions were critical to maintain the binding mode of artemisinin and its derivatives with MD-2.
青蒿素(又名青蒿素),青蒿提取物的有效成分,被广泛用作抗疟药物。先前的研究表明,青蒿素及其衍生物还具有有效的抗炎和免疫调节特性,但直接的分子靶标仍不清楚。最近,有几项报道提到髓系分化因子 2(MD-2,也称为淋巴细胞抗原 96)可能是青蒿素在抑制脂多糖信号传导中的内源性靶标。然而,青蒿素与 MD-2 之间的确切相互作用仍不完全清楚。在这里,采用实验和计算方法阐明了青蒿素及其抑制机制之间的关系。实验结果表明,蒿甲醚比青蒿素和青蒿琥酯具有更高的抗炎活性。分子对接结果表明,青蒿素、青蒿琥酯和蒿甲醚具有相似的结合构象,并且在整个分子动力学模拟过程中所有复合物都保持稳定,而青蒿素及其衍生物与 MD-2 的结合降低了 TLR4(Toll-Like Receptor 4)/MD-2 的稳定性。此外,与青蒿素和青蒿琥酯相比,蒿甲醚的结合能较低,这与实验结果一致。Leu61、Leu78 和 Ile117 确实是对结合自由能有贡献的关键残基。结合自由能分析进一步证实,疏水相互作用对于维持青蒿素及其衍生物与 MD-2 的结合模式至关重要。