Shen Xin, Zhang Xin, Li Kaiyu, Huang Guangming, Li Xinyu, Hou Yunlong, Ge Xin
Department of Pharmacy, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, China.
Luoyang Orthopedic-Traumatological Hospital of Henan Province (Henan Provincial Orthopedic Hospital), Luoyang, 471002, Henan, China.
Heliyon. 2024 Aug 3;10(16):e35793. doi: 10.1016/j.heliyon.2024.e35793. eCollection 2024 Aug 30.
This study explores the mechanism by which obstructive jaundice (OJ) induces liver damage through pyroptosis. We induced OJ in rats via bile duct ligation and assessed liver damage using serum biochemical markers and histological analysis of liver tissue. Pyroptosis was investigated through immunofluorescence, ELISA, Western blot, and quantitative RT-PCR techniques. Additionally, we examined intestinal function and fecal microbiota alterations in the rats using 16S rDNA sequencing. In vitro experiments involved co-culturing Kupffer cells and hepatocytes, which were then exposed to bile and lipopolysaccharide (LPS). Our findings indicated that OJ modified the gut microbiota, increasing LPS levels, which, in conjunction with bile, initiated a cycle of inflammation, fibrosis, and cell death in the liver. Mechanistically, OJ elevated necrotic markers such as ATP, which in turn activated pyroptotic pathways. Increased levels of pyroptosis-related molecules, including NLRP3, caspase-1, gasdermin D, and IL-18, were confirmed. In our co-cultured cell model, bile exposure resulted in cell death and ATP release, leading to the activation of the NLRP3 inflammasome and its downstream effectors, caspase-1 and IL-18. The combination of bile and LPS significantly intensified pyroptotic responses. This study is the first to demonstrate that LPS and bile synergistically exacerbate liver injury by promoting necrosis and pyroptosis, unveiling a novel mechanism of OJ-associated hepatic damage and suggesting avenues for potential preventive or therapeutic interventions.
本研究探讨阻塞性黄疸（OJ）通过细胞焦亡诱导肝损伤的机制。我们通过胆管结扎在大鼠中诱导OJ，并使用血清生化标志物和肝组织的组织学分析评估肝损伤。通过免疫荧光、酶联免疫吸附测定（ELISA）、蛋白质免疫印迹法和定量逆转录聚合酶链反应（RT-PCR）技术研究细胞焦亡。此外，我们使用16S核糖体DNA（rDNA）测序检查大鼠的肠道功能和粪便微生物群变化。体外实验包括将库普弗细胞和肝细胞共培养，然后使其暴露于胆汁和脂多糖（LPS）中。我们的研究结果表明，OJ改变了肠道微生物群，增加了LPS水平，LPS与胆汁一起引发了肝脏中的炎症、纤维化和细胞死亡循环。从机制上讲，OJ升高了坏死标志物如三磷酸腺苷（ATP），进而激活细胞焦亡途径。证实了细胞焦亡相关分子水平升高，包括NLRP3、半胱天冬酶-1、gasdermin D和白细胞介素-18（IL-18）。在我们的共培养细胞模型中，胆汁暴露导致细胞死亡和ATP释放，从而导致NLRP3炎性小体及其下游效应物半胱天冬酶-1和IL-18的激活。胆汁和LPS的组合显著增强了细胞焦亡反应。本研究首次证明LPS和胆汁通过促进坏死和细胞焦亡协同加剧肝损伤，揭示了OJ相关肝损伤的新机制，并为潜在的预防或治疗干预提供了途径。
