Wu Jia-Shen, Xu Chi-Yu, Mo Su-Min, Wu Xin-Mou, Du Ze-Bang, Che Lin, Zhang Yi-Ling, Yang Kai-Li, Li Ting-Dong, Ge Sheng-Xiang, Zhang Tian-Ying, Lin Zhong-Ning, Lin Yu-Chun
State Key Laboratory of Vaccines for Infectious Diseases, Xiang An Biomedicine Laboratory, Xiang'an Hospital of Xiamen University, National Innovation Platform for Industry-Education Integration in Vaccine Research, School of Public Health, Xiamen University, Xiamen 361102, China.
J Adv Res. 2025 May 9. doi: 10.1016/j.jare.2025.05.005.
The complex interplay between protein palmitoylation, mitochondrial dynamics, and inflammatory responses plays a pivotal role in respiratory diseases. One significant feature of post-acute coronavirus disease 2019 (COVID-19) syndrome (PACS) is the occurrence of a storm of inflammatory cytokines related to the NOD-like receptor protein 3 (NLRP3). However, the specific mechanisms via which palmitoylation affects mitochondrial function and its impact on the NLRP3 inflammasome under pathological respiratory conditions remain to be elucidated.
This study aimed to investigate how protein palmitoylation influences inflammatory responses and mitochondrial dynamics in respiratory diseases, such as those induced by the SARS-CoV-2 spike S protein in PACS, thereby providing a therapeutic target for inflammatory lung injury.
In vivo experiments were conducted using AdV5-pADM-CMV-COVID-19-S (AdV5-S) nasal drip-treated C57BL/6 mice to assess NLRP3 inflammasome activation and inflammatory response. In vitro experiments were performed using pCMV-S-transfected human lung epithelial BEAS-2B cells to analyze the effects of DHHC5-mediated palmitoylation of cyclooxygenase-2 (COX-2) at cysteine 555 (COX-2) on mitochondrial metabolism and NLRP3 inflammasome activation.
Palmitoylation of COX-2 enhanced its interaction with hexokinase 2 (HK2) to regulate mitochondrial metabolic reprogramming, leading to NLRP3 inflammasome activation and pyroptosis. Pharmacological and genetic suppression of palmitoylation diminished the mitochondrial localization of palmitoylated COX-2 and its interaction with HK2, thereby reducing mitochondrial metabolic reprogramming. Furthermore, genetic intervention targeting DHHC5 (shDhhc5) alleviated NLRP3 activation and pyroptosis, mitigating the chronic inflammatory damage associated with PACS.
This study highlights the regulatory role of COX-2 palmitoylation in mitochondrial metabolism and lung inflammatory injury, and suggests potential therapeutic targets to combat respiratory pathogenesis linked to palmitoylated COX-2.
蛋白质棕榈酰化、线粒体动力学和炎症反应之间的复杂相互作用在呼吸系统疾病中起着关键作用。2019年冠状病毒病（COVID-19）后急性综合征（PACS）的一个显著特征是出现与NOD样受体蛋白3（NLRP3）相关的炎症细胞因子风暴。然而，在病理性呼吸条件下，棕榈酰化影响线粒体功能的具体机制及其对NLRP3炎性小体的影响仍有待阐明。
本研究旨在探讨蛋白质棕榈酰化如何影响呼吸系统疾病中的炎症反应和线粒体动力学，如PACS中由严重急性呼吸综合征冠状病毒2（SARS-CoV-2）刺突S蛋白诱导的疾病，从而为炎症性肺损伤提供治疗靶点。
使用经腺病毒5型-pADM-CMV-COVID-19-S（AdV5-S）滴鼻处理的C57BL/6小鼠进行体内实验，以评估NLRP3炎性小体的激活和炎症反应。使用pCMV-S转染的人肺上皮BEAS-2B细胞进行体外实验，以分析二氢神经酰胺合酶5（DHHC5）介导的环氧化酶-2（COX-2）半胱氨酸555位点的棕榈酰化对线粒体代谢和NLRP3炎性小体激活的影响。
COX-2的棕榈酰化增强了其与己糖激酶2（HK2）的相互作用以调节线粒体代谢重编程，导致NLRP3炎性小体激活和细胞焦亡。棕榈酰化的药理学和遗传学抑制减少了棕榈酰化COX-2的线粒体定位及其与HK2的相互作用，从而减少了线粒体代谢重编程。此外，靶向DHHC5的基因干预（shDhhc5）减轻了NLRP3激活和细胞焦亡，减轻了与PACS相关的慢性炎症损伤。
本研究突出了COX-2棕榈酰化在线粒体代谢和肺部炎症损伤中的调节作用，并提出了对抗与棕榈酰化COX-2相关的呼吸发病机制的潜在治疗靶点。
