一种抑制NF-κB活化的有效抗炎剂

Discovery of an effective anti-inflammatory agent for inhibiting the activation of NF-κB

一种抑制NF-κB活化的有效抗炎剂

Authors: Yaoyao Yan,Qi Li, Feilong Zhou, Yujie Jian, Liu Xinhua, Xing Chen and Yong Hu 

Source：JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY 

Doi: 10.1080/14756366.2023.2225135

Abstract 

        In this study, based on the effect of compounds on the activation of NF-κB and NO release, compound 51 was discovered as the best one with NO release inhibition IC50 value was 3.1 ± 1.1 μM and NF-κB activity inhibition IC50 value was 172.2 ± 11.4 nM. Compound 51 could inhibit the activation of NF-κB through suppressing phosphorylation and nuclear translocation of NF-κB, and suppress LPS-induced inflammatory response in RAW264.7 cells, such as the over-expression of TNF-α and IL-6, which were target genes of NF-κB. This compound also showed preferable anti-inflammatory activity in vivo, including alleviating significantly gastric distention and splenomegaly caused by LPS stimulation, reducing the level of oxidative stress induced by LPS, and inhibiting the expression of IL-6 and TNF-α in serum. Thus, it’s reasonable to consider that this compound is a promising small molecule with anti-inflammatory effect for inhibiting the NF-κB signalling pathway

Conclusion

        The NF-κB pathway is implicated as a typical inflammatory signalling pathway, its activation leads to a series of inflammatory response. Thus, inhibiting NF-κB activation has long been considered as a promising approach to alleviate many inflammatory diseases. In this study, we synthesised a series of compounds, among them, compound 51 showed favourable NO release inhibition activity (IC50=3.1 μM) and inhibited NF-κB transcriptional activity strongly. Further studies showed that this compound suppressed LPS and TNF-α induced NF-κB activation, including the effect on phosphorylation of and nuclear translocation of NF-κB. In addition, title compound also exert inhibition effect on MAPKs signal, the expression of phosphorylation of P38, JNK and ERK was significantly decreased. NF-κB activation triggered the downstream inflammatory response, we found that compound 51 decrease the levels of IL-6, TNF-α and ROS, which indicated this compound could alleviate LPS and TNF-α induced inflammatory response through inhibiting NF-κB activation. In vivo study, we evaluated the anti-inflammatory activity of compound 51 using animal model of acute inflammation induced by LPS. LPS stimulation caused changes in organ tissues in vivo, compound reduced inflammatory symptoms, including gastric distention and splenomegaly. The result also showed that title compound decreased the levels of IL-6 and TNF-α in blood. In addition, it was confirmed that this compound could decrease ROS level in vitro, which indicated it could alleviate oxidative stress. So we also measured the activity of SOD and MDA in vivo, two key indicators of evaluate the level of oxidative stress. We found that treatment of compound increased SOD activity and decreased MDA activity. What’s more, title compound suppressed the activation of NF-κB signalling in spleen, which indicated that this compound inhibited LPS-induced inflammation through inhibiting NF-κB activity. Overall, we obtained a novel compound with favourable anti-inflammatory activity in vitro and in vivo, which is meaningful for the development of NF-κB inhibitors and anti-inflammatory drugs.

摘要

       本研究基于化合物对NF-κB活化和NO释放的影响，发现化合物51是抑制NO释放IC的最佳化合物50值为 3.1 ± 1.1 μM 和 NF-κB 活性抑制 IC50值为 172.2 ± 11.4 nM。化合物51可通过抑制NF-κB的磷酸化和核易位来抑制NF-κB的活化，抑制LPS诱导的RAW264.7细胞炎症反应，如NF-κB靶基因TNF-α和IL-6的过表达。该化合物在体内还显示出较好的抗炎活性，包括显着缓解LPS刺激引起的胃胀和脾肿大，降低LPS诱导的氧化应激水平，以及抑制血清中IL-6和TNF-α的表达。因此，可以合理地认为该化合物是一种很有前途的小分子，具有抑制NF-κB信号通路的抗炎作用。

结论

        NF-κB通路是一种典型的炎症信号通路，其激活可引起一系列炎症反应。因此，抑制NF-κB活化一直被认为是缓解许多炎症性疾病的一种有希望的方法。在本研究中，我们合成了一系列化合物，其中化合物51具有良好的NO释放抑制活性(IC50=3.1 μM)，并对NF-κB转录活性有较强的抑制作用。进一步研究表明，该化合物可抑制LPS和TNF-α诱导的NF-κB活化，包括对NF-κB磷酸化和核易位的影响。此外，标题化合物对MAPKs信号也有抑制作用，P38、JNK和ERK的磷酸化表达显著降低。NF-κB激活触发下游炎症反应，我们发现化合物51降低IL-6、TNF-α和ROS水平，表明该化合物可能通过抑制NF-κB激活来缓解LPS和TNF-α诱导的炎症反应。在体内实验中，我们采用LPS诱导的急性炎症动物模型来评价化合物51的抗炎活性。LPS刺激引起体内器官组织的改变，复合减轻炎症症状，包括胃胀和脾肿大。结果还表明，标题化合物降低了血液中IL-6和TNF-α的水平。此外，体外实验证实该化合物可以降低ROS水平，表明其具有减轻氧化应激的作用。因此，我们还测量了体内SOD和MDA的活性，这是评估氧化应激水平的两个关键指标。我们发现，化合物处理增加了SOD活性，降低了MDA活性。此外，标题化合物抑制脾脏NF-κB信号的激活，表明该化合物通过抑制NF-κB活性抑制lps诱导的炎症。总的来说，我们获得了一个体外和体内具有良好抗炎活性的新化合物，这对NF-κB抑制剂和抗炎药物的开发具有重要意义。