目的:探究cGAS‑STING通路和铁自噬在脂质运载蛋白2（lipocalin‑2，LCN2）基因敲除小鼠脓毒症肝脏损伤铁死亡中的变化及机制。 方法:SPF级雄性C57BL/6J小鼠36只随机分为假手术（WT）组、盲肠结扎穿刺（CLP）组、LCN2基因敲除（LCN2^‑/‑）组、LCN2^‑/‑后CLP处理（LCN2^‑/‑+CLP）组，每组9只。CLP造模24 h后H&E染色观察肝脏结构的病理变化；检测各组血清丙氨酸氨基转移酶（alanine aminotransferase，ALT）、天冬氨酸氨基转移酶（aspartate aminotransferase，AST）水平、肝脏组织丙二醛（malondialdehyde，MDA）、超氧化物歧化酶（superoxide dismutase，SOD）水平；DHE荧光染色观察肝脏组织活性氧水平；Western blot检测肝脏组织LCN2、GPX4、FTH1、NCOA4、LC3B、cGAS、STING蛋白表达水平。 结果:CLP术后，H&E染色结果显示小鼠肝脏细胞气球样变和炎症细胞浸润，LCN2基因敲除后有所缓解。与WT组相比，CLP组ALT、AST、MDA水平升高，SOD水平降低（P<0.001）；肝脏组织GPX4、FTH1蛋白表达水平降低，LCN2、NCOA4、LC3BⅡ/LC3BⅠ、cGAS、STING蛋白表达水平升高（P<0.01）。与CLP组相比，LCN2^‑/‑+CLP组的ALT、AST、MDA水平降低，SOD水平升高（P<0.01）；GPX4、FTH1蛋白表达水平升高，NCOA4、LC3BⅡ/LC3BⅠ、cGAS、STING蛋白表达水平降低（P<0.05）。 结论:敲除LCN2基因通过抑制铁自噬及cGAS‑STING通路减轻脓毒症小鼠肝细胞铁死亡的发生。

Objective:To investigate the changes and mechanism of cGAS‑STING pathway and ferritinophagy in ferroptosis of sepsis‑induced liver injury in lipocalin‑2 （LCN2） gene knockout mice. Methods:A total of 36 SPF‑grade male C57BL/6J mice were randomly divided into 4 groups： the sham surgery （WT） group， the cecal ligation and puncture （CLP） group， the LCN2 gene knockout （LCN2^‑/‑） group， and the LCN2^‑/‑ with CLP treatment （LCN2^‑/‑+CLP） group， with 9 in each group. After 24 hours of CLP modeling， liver tissue pathological changes were observed using H&E staining. The levels of serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST）， as well as the levels of liver malondialdehyde （MDA） and superoxide dismutase （SOD） were analyzed. Reactive oxygen species levels in liver tissue were assessed using the DHE probe. The protein expression levels of LCN2， GPX4， FTH1， NCOA4， LC3B， cGAS， and STING in liver tissues were detected by Western blot. Results:After CLP surgery， the result of H&E staining revealed balloon‑like degeneration of hepatocytes and inflammatory cell infiltration in liver tissues， which were alleviated after LCN2 gene knockout. Compared to the WT group， the CLP group showed increased levels of ALT， AST， and MDA， and a decreased level of SOD （P<0.001）， as well as decreased expression levels of GPX4 and FTH1 proteins in liver tissue， and increased expression levels of NCOA4， LC3BⅡ/LC3BⅠ， cGAS， and STING proteins （P<0.01）. Compared to the CLP group， ALT， AST， and MDA levels decreased， SOD level increased （P<0.01）； CPX4 and FTH1 protein expression levels increased， and NCOA4， LC3BⅡ/LC3BⅠ， cGAS， and STING protein expression levels decreased （P<0.05） in the LCN2^‑/‑+CLP group. Conclusion:Knockout of the LCN2 gene alleviates ferroptosis in hepatocytes of septic mice by inhibiting ferritinophagy and the cGAS‑STING pathway.

R459.7

安徽省高校优秀科研创新团队资助项目（2022AH010083）；蚌埠医科大学国家自然科学基金孵育项目（2024byfy004）；蚌埠医科大学科研创新项目（Byycx24001，Byycx22014）