Kingsley Manoj Kumar, Rao Gurugubelli Krishna, Bhat Ballambattu Vishnu
Department of Neonatology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India.
Department of Pulmonary Medicine, Christian Medical College, Vellore, India.
Bioinform Biol Insights. 2024 Mar 16;18:11779322241233436. doi: 10.1177/11779322241233436. eCollection 2024.
Narciclasine is an alkaloid belonging to the Amaryllidaceae family which has been reported to have many beneficial properties. Especially its anticancer properties have been widely reported. Here, we have focused on its potential use in suppressing the inflammatory response in sepsis using in silico methods. Lipopolysaccharide (LPS) is an endotoxin which is present in the outer membrane of gram-negative bacteria and is a crucial player in the pathogenesis of gram-negative sepsis. Activation of toll-like receptor 4 (TLR4) signaling by LPS is an important event in the pathogenesis of gram-negative sepsis. This initiates a downstream signaling pathway comprising of several adaptor proteins such as toll/interleukin-1 receptor domain-containing adapter protein (TIRAP), myeloid differentiation primary response protein 88 (MyD88), interleukin-1 receptor-associated kinase (IRAK)-1, IRAK-4, interferon regulatory factor 3 (IRF-3), tumor necrosis factor receptor-associated factor 6 (TRAF-6) leading to nuclear factor kappa B (NF-κβ) activation resulting in elevated production of inflammatory cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6. S100 calcium binding proteins A8/A9 (S100A8/A9) have been found to be an agonist of TLR4, and it amplifies the inflammatory response in sepsis. Molecular docking studies of narciclasine with target proteins associated with the LPS-TLR4 pathway showed that it has good binding affinity and stable interactions with the targets studied. Molecular dynamics (MD) simulation studies over 100 ns showed that most of the ligand-target complexes were stable. The structures of all the targets except TRAF-6 were retrieved from the Protein Data Bank (PDB) database. Homology modeling was done to predict the 3-dimensional structure of TRAF-6. MD simulation of narciclasine-TRAF-6 complex showed that the structure is stable. Metapocket was used for active site prediction in the target proteins. Toxicity analysis by admetSAR revealed that narciclasine was readily biodegradable and exhibited minimum toxicity. These results indicate that narciclasine has effective anti-inflammatory properties which could be useful in suppressing the inflammatory response in sepsis.
水仙环素是一种属于石蒜科的生物碱，据报道具有许多有益特性。尤其是其抗癌特性已被广泛报道。在此，我们利用计算机模拟方法重点研究了其在抑制脓毒症炎症反应中的潜在用途。脂多糖（LPS）是一种存在于革兰氏阴性菌外膜的内毒素，是革兰氏阴性菌脓毒症发病机制中的关键因素。LPS激活Toll样受体4（TLR4）信号通路是革兰氏阴性菌脓毒症发病机制中的一个重要事件。这启动了一个下游信号通路，该通路由几种衔接蛋白组成，如含Toll/白细胞介素-1受体结构域的衔接蛋白（TIRAP）、髓样分化初级反应蛋白88（MyD88）、白细胞介素-1受体相关激酶（IRAK）-1、IRAK-4、干扰素调节因子3（IRF-3）、肿瘤坏死因子受体相关因子6（TRAF-6），导致核因子κB（NF-κβ）激活，进而导致炎症细胞因子如肿瘤坏死因子α（TNF-α）和白细胞介素（IL）-6的产生增加。已发现S100钙结合蛋白A8/A9（S100A8/A9）是TLR4的激动剂，它会放大脓毒症中的炎症反应。水仙环素与LPS-TLR4通路相关靶蛋白的分子对接研究表明，它与所研究的靶标具有良好的结合亲和力和稳定的相互作用。超过100纳秒的分子动力学（MD）模拟研究表明，大多数配体-靶标复合物是稳定的。除TRAF-6外，所有靶标的结构均从蛋白质数据库（PDB）中检索获得。通过同源建模预测了TRAF-6的三维结构。水仙环素-TRAF-6复合物的MD模拟表明该结构是稳定的。利用Metapocket预测靶蛋白的活性位点。通过admetSAR进行的毒性分析表明，水仙环素易于生物降解且毒性最小。这些结果表明，水仙环素具有有效的抗炎特性，可用于抑制脓毒症中的炎症反应。
