紫杉醇通过促进巨噬细胞中 NLRP3 炎性小体的激活来增强先天免疫。
Paclitaxel Enhances the Innate Immunity by Promoting NLRP3 Inflammasome Activation in Macrophages.
机构信息
Department of Immunobiology, College of Life Science and Technology, Jinan University, Guangzhou, China.
Department of Cell Biology, College of Life Science and Technology, Jinan University, Guangzhou, China.
出版信息
Front Immunol. 2019 Jan 29;10:72. doi: 10.3389/fimmu.2019.00072. eCollection 2019.
Microtubules play critical roles in regulating the activation of NLRP3 inflammasome and microtubule-destabilizing agents such as colchicine have been shown to suppress the activation of this inflammasome. However, it remains largely unknown whether paclitaxel, a microtubule-stabilizing agent being used in cancer therapy, has any influences on NLRP3 inflammasome activation. Here we showed that paclitaxel pre-treatment greatly enhanced ATP- or nigericin-induced NLRP3 inflammasome activation as indicated by increased release of cleaved caspase-1 and mature IL-1β, enhanced formation of ASC speck, and increased gasdermin D cleavage and pyroptosis. Paclitaxel time- and dose-dependently induced α-tubulin acetylation in LPS-primed murine and human macrophages and further increased ATP- or nigericin-induced α-tubulin acetylation. Such increased α-tubulin acetylation was significantly suppressed either by resveratrol or NAD (coenzyme required for deacetylase activity of SIRT2), or by genetic knockdown of (gene encoding α-tubulin acetyltransferase 1). Concurrently, the paclitaxel-mediated enhancement of NLRP3 inflammasome activation was significantly suppressed by resveratrol, NAD, or knockdown, indicating the involvement of paclitaxel-induced α-tubulin acetylation in the augmentation of NLRP3 inflammasome activation. Similar to paclitaxel, epothilone B that is another microtubule-stabilizing agent also induced α-tubulin acetylation and increased NLRP3 inflammasome activation in macrophages in response to ATP treatment. Consistent with the results, intraperitoneal administration of paclitaxel significantly increased serum IL-1β levels, reduced bacterial burden, dampened infiltration of inflammatory cells in the liver, and improved animal survival in a mouse model of bacterial infection. Collectively, our data indicate that paclitaxel potentiated NLRP3 inflammasome activation by inducing α-tubulin acetylation and thereby conferred enhanced antibacterial innate responses, suggesting its potential application against pathogenic infections beyond its use as a chemotherapeutic agent.
微管在调节 NLRP3 炎性小体的激活中起着关键作用,秋水仙碱等微管去稳定剂已被证明能抑制这种炎性小体的激活。然而,紫杉醇作为一种用于癌症治疗的微管稳定剂,是否对 NLRP3 炎性小体的激活有任何影响,在很大程度上仍不清楚。在这里,我们显示紫杉醇预处理大大增强了 ATP 或 Nigericin 诱导的 NLRP3 炎性小体的激活,表现为切割的 caspase-1 和成熟的 IL-1β的释放增加,ASC 斑点的形成增强,以及 gasdermin D 的切割和细胞焦亡增加。紫杉醇时间和剂量依赖性地诱导 LPS 预刺激的小鼠和人巨噬细胞中的α-微管蛋白乙酰化,并进一步增加 ATP 或 Nigericin 诱导的α-微管蛋白乙酰化。这种增加的α-微管蛋白乙酰化被白藜芦醇或 NAD(SIRT2 去乙酰化酶活性所需的辅酶)显著抑制,或通过 (编码α-微管蛋白乙酰转移酶 1 的基因)的基因敲低显著抑制。同时,紫杉醇介导的 NLRP3 炎性小体激活的增强作用被白藜芦醇、NAD 或 基因敲低显著抑制,表明紫杉醇诱导的α-微管蛋白乙酰化参与了 NLRP3 炎性小体激活的增强。与紫杉醇类似,另一种微管稳定剂埃坡霉素 B 也诱导α-微管蛋白乙酰化,并增加巨噬细胞中 NLRP3 炎性小体对 ATP 处理的反应。与结果一致,紫杉醇腹腔内给药显著增加血清 IL-1β水平,减少细菌负荷,减轻肝脏炎症细胞浸润,提高细菌感染小鼠模型的动物存活率。总之,我们的数据表明,紫杉醇通过诱导α-微管蛋白乙酰化增强 NLRP3 炎性小体的激活,从而赋予增强的抗菌先天反应,表明其除了作为化疗药物外,在治疗致病性感染方面具有潜在的应用价值。