Zhang Xuefen, Sun Yue, Zhang Wandong
First School of Clinical Medicine, Anhui University of Chinese Medicine, Hefei 230031, China.
Department of Rheumatology, First Affiliated Hospital, Anhui University of Chinese Medicine, Hefei 230031, China.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi. 2024 Sep;40(9):818-825.
Objective To explore the role and potential mechanism of caspase activation and recruitment domain-containing nucleotide-binding oligomerization domain-like receptor 3 (NLRC3) in the immune inflammatory response induced by macrophage pyroptosis in patients with rheumatoid arthritis (RA). Methods Fifty RA patients and ten healthy volunteers were selected according to inclusion criteria. Peripheral blood macrophages were extracted and divided into six groups: normal control(NC), RA macrophage model (RA-MC), RA-MC with NLRC3 overexpression, RA-MC with NLRC3 knockdown, RA-MC with STING overexpression, and RA-MC with STING knockdown groups. Macrophage pyroptosis was observed using transmission electron microscopy. The mRNA expressions of NLRC3, STING, caspase-1, and GSDMD were detected using RT-qPCR. interleukin 1β (IL-1β) and IL-18 levels in cell supernatants were measured using ELISA. Results Compared to the NC group, the RA-MC group showed characteristics of pyroptosis. Compared to the RA-MC group, the groups of RA-MC with NLRC3 overexpression and RA-MC with STING knockdown showed improved pyroptosis, while the groups of RA-MC with NLRC3 knockdown and RA-MC with STING overexpression demonstrated exacerbated pyroptosis. Compared to the NC group, the RA-MC group showed increased mRNA expression levels of STING, caspase-1 and GSDMD, as well as increased levels of the inflammatory cytokines IL-1β and IL-18, but decreased NLRC3 mRNA expression level. Compared to the RA-MC group, the groups of RA-MC with NLRC3 overexpression and RA-MC with STING knockdown showed reduced mRNA expression levels of caspase-1 and GSDMD, as well as reduced inflammatory factors, while the groups of RA-MC with NLRC3 knockdown and RA-MC with STING overexpression had opposite results. Compared to the RA-MC group, the group of RA-MC with NLRC3 overexpression showed a decreased STING mRNA expression level, while the group of RA-MC with NLRC3 knockdown demonstrated an increased level. Conclusion NLRC3 can inhibit the STING signaling pathway, reduce pyroptosis proteins caspase-1 and GSDMD, antagonize macrophage pyroptosis, and lower the levels of inflammatory cytokines IL-1β and IL-18, thereby alleviating the immune inflammatory response in RA patients.
目的 探讨含半胱天冬酶激活和募集结构域的核苷酸结合寡聚化结构域样受体3（NLRC3）在类风湿关节炎（RA）患者巨噬细胞焦亡诱导的免疫炎症反应中的作用及潜在机制。方法 根据纳入标准选取50例RA患者和10名健康志愿者。提取外周血巨噬细胞并分为六组：正常对照（NC）组、RA巨噬细胞模型（RA-MC）组、NLRC3过表达的RA-MC组、NLRC3敲低的RA-MC组、STING过表达的RA-MC组和STING敲低的RA-MC组。采用透射电子显微镜观察巨噬细胞焦亡情况。使用RT-qPCR检测NLRC3、STING、半胱天冬酶-1（caspase-1）和Gasdermin D（GSDMD）的mRNA表达。采用酶联免疫吸附测定法（ELISA）检测细胞上清液中白细胞介素1β（IL-1β）和IL-18水平。结果 与NC组相比，RA-MC组呈现焦亡特征。与RA-MC组相比，NLRC3过表达的RA-MC组和STING敲低的RA-MC组焦亡情况改善，而NLRC3敲低的RA-MC组和STING过表达的RA-MC组焦亡情况加剧。与NC组相比，RA-MC组STING、caspase-1和GSDMD的mRNA表达水平升高，炎症细胞因子IL-1β和IL-18水平升高，但NLRC3 mRNA表达水平降低。与RA-MC组相比，NLRC3过表达的RA-MC组和STING敲低的RA-MC组caspase-1和GSDMD的mRNA表达水平降低，炎症因子水平降低，而NLRC3敲低的RA-MC组和STING过表达的RA-MC组结果相反。与RA-MC组相比，NLRC3过表达的RA-MC组STING mRNA表达水平降低，而NLRC3敲低的RA-MC组水平升高。结论 NLRC3可抑制STING信号通路，减少焦亡蛋白caspase-1和GSDMD，拮抗巨噬细胞焦亡，降低炎症细胞因子IL-1β和IL-18水平，从而减轻RA患者的免疫炎症反应。
