败血症是一种威胁生命的器官功能障碍，在重症监护病房中是导致死亡的主要原因之一。炎性细胞噬菌作用增强因子（macrophage pyroptosis）与败血症的发生紧密相关，而微小核糖核酸(miRNAs)已被证明在这一过程中起到重要作用。然而，miR-122-3p在败血症进展中对炎性细胞噬菌作用的具体作用和其潜在机制尚未完全阐明。我们采用脂多糖(LPS)激活的巨噬细胞建立了体外败血症模型，随后将miR-122-3p模拟剂转染到RAW264.7巨噬细胞中。随后，我们使用细胞活力、蛋白免疫印迹和实时荧光定量PCR实验确定了miR-122-3p对细胞存活和炎性细胞噬菌作用的影响。然后，我们采用双荧光素酶报告基因实验验证了miR-122-3p与NLR pyrin结构域含1 (NLRP1) mRNA的结合亲和性。最后，我们使用ELISA确定了前炎性细胞因子（白细胞介素(IL)-2、IL-6和肿瘤坏死因子-α(TNF-α))的分泌。结果表明，LPS处理导致RAW264.7细胞中前炎性细胞因子（包括IL-2、IL-6和TNF-α）的产生显著增加。我们观察到miR-122-3p的过表达有效恢复了细胞存活能力，并减弱了LPS促进的关键炎症标志物的表达，如半胱天冬氨酸蛋白酶-1，前半胱天冬氨酸蛋白酶-1，IL-18，IL-1β，NLRP3，包含CARD的凋亡相关斑点样蛋白以及裂解的气孔溶血素-D。我们的数据显示，miR-122-3p能够直接与NLRP1结合并抑制其表达。这些结果证实了miR-122-3p在抑制败血症中通过抑制炎性细胞噬菌作用的NLRP1依赖性途径中起到了关键作用。因此，miR-122-3p成为了败血症的一个有前途的治疗靶点。© 2023由临床科学家协会所有。

Sepsis, a life-threatening organ dysfunction, is among the leading causes of mortality in intensive care units. Sepsis occurrence is associated with macrophage pyroptosis, and microRNAs (miRNAs) have emerged as key factors in this process. However, the specific role of miR-122-3p in pyroptosis during sepsis progression and its underlying mechanisms remain to be fully elucidated.We established an in vitro sepsis model using lipopolysaccharide (LPS)-activated macrophages, followed by transfection of a miR-122-3p mimic into RAW264.7 macrophages. We subsequently determined the effects of miR-122-3p on cell viability and pyroptosis using cell viability, western blot, and qPCR assays. The binding affinity between miR-122-3p and NLR pyrin domain containing 1 (NLRP1) mRNA was then confirmed using a dual-luciferase reporter assay. Finally, the secretion of pro-inflammatory cytokines (interleukin (IL)-2, IL-6, and tumor necrosis factor-α (TNF-α) was determined using ELISA.The results revealed that LPS treatment lead to a significant increase in the production of pro-inflammatory cytokines including IL-2, IL-6, and TNF-α in RAW264.7 cells. We observed that overexpression of miR-122-3p effectively restored cell viability and attenuated the expression of key inflammatory markers promoted by LPS, such as caspase-1, pro-caspase-1, IL-18, IL-1β, NLRP3, apoptosis-associated speck-like protein containing CARD, and cleaved- gasdermin-D. Our data indicate that miR-122-3p is capable of directly bounding to NLRP1 and inhibiting its expression.These results confirmed that miR-122-3p plays a crucial role in the inhibition of sepsis by suppressing macrophage pyroptosis in an NLRP1-dependent manner. Therefore, miR-122-3p presents as a promising therapeutic target for sepsis.© 2023 by the Association of Clinical Scientists, Inc.