Dysregulated metabolism, cell death, and inflammation contribute to the development of metabolic dysfunction-associated steatohepatitis (MASH). Pyroptosis, a recently identified form of programmed cell death, is closely linked to inflammation. However, the precise role of pyroptosis, particularly gasdermin-E (GSDME), in MASH development remains unknown. In this study, we observed GSDME cleavage and GSDME-associated interleukin-1β (IL-1β)/IL-18 induction in liver tissues of MASH patients and MASH mouse models induced by a choline-deficient high-fat diet (CDHFD) or a high-fat/high-cholesterol diet (HFHC). Compared with wild-type mice, global GSDME knockout mice exhibited reduced liver steatosis, steatohepatitis, fibrosis, endoplasmic reticulum stress, lipotoxicity and mitochondrial dysfunction in CDHFD- or HFHC-induced MASH models. Moreover, GSDME knockout resulted in increased energy expenditure, inhibited intestinal nutrient absorption, and reduced body weight. In the mice with GSDME deficiency, reintroduction of GSDME in myeloid cells—rather than hepatocytes—mimicked the MASH pathologies and metabolic dysfunctions, as well as the changes in the formation of neutrophil extracellular traps and hepatic macrophage/monocyte subclusters. These subclusters included shifts in Tim4⁺ or CD163⁺ resident Kupffer cells, Ly6C^hi pro-inflammatory monocytes, and Ly6C^loCCR2^loCX3CR1^hi patrolling monocytes. Integrated analyses of RNA sequencing and quantitative proteomics revealed a significant GSDME-dependent reduction in citrullination at the arginine-114 (R114) site of dynamin-related protein 1 (Drp1) during MASH. Mutation of Drp1 at R114 reduced its stability, impaired its ability to redistribute to mitochondria and regulate mitophagy, and ultimately promoted its degradation under MASH stress. GSDME deficiency reversed the de-citrullination of Drp1^R114, preserved Drp1 stability, and enhanced mitochondrial function. Our study highlights the role of GSDME in promoting MASH through regulating pyroptosis, Drp1 citrullination-dependent mitochondrial function, and energy balance in the intestine and liver, and suggests that GSDME may be a potential therapeutic target for managing MASH.

代谢失调、细胞死亡和炎症会导致代谢功能障碍相关脂肪性肝炎 (MASH) 的发生。焦亡是最近发现的一种程序性细胞死亡形式，与炎症密切相关。然而，细胞焦亡，尤其是gasdermin-E (GSDME)，在MASH 发育中的确切作用仍不清楚。在这项研究中，我们观察了 MASH 患者和由缺乏胆碱的高脂饮食 (CDHFD) 或高脂肪/高胆固醇饮食（HFHC）。与野生型小鼠相比，全GSDME基因敲除小鼠在CDHFD或HFHC诱导的MASH模型中表现出肝脏脂肪变性、脂肪性肝炎、纤维化、内质网应激、脂毒性和线粒体功能障碍的减少。此外，GSDME敲除导致能量消耗增加，抑制肠道营养吸收，并减轻体重。在患有 GSDME 缺陷的小鼠中，在骨髓细胞（而不是肝细胞）中重新引入 GSDME 模拟了 MASH 病理和代谢功能障碍，以及中性粒细胞胞外陷阱和肝巨噬细胞/单核细胞亚群形成的变化。这些亚群包括 Tim4 ⁺或 CD163 ⁺驻留 Kupffer 细胞、Ly6C ^hi促炎单核细胞和 Ly6C ^lo CCR2 ^lo CX3CR1 ^hi巡逻单核细胞的转变。 RNA 测序和定量蛋白质组学的综合分析揭示了 MASH 过程中动力相关蛋白 1 (Drp1) 精氨酸 114 (R114) 位点的瓜氨酸化显着减少，依赖于 GSDME。 Drp1 R114 处的突变降低了其稳定性，损害了其重新分配到线粒体和调节线粒体自噬的能力，并最终促进了其在 MASH 胁迫下的降解。 GSDME 缺陷逆转了 Drp1 ^R114的去瓜氨酸化，保留了 Drp1 的稳定性并增强了线粒体功能。我们的研究强调了 GSDME 通过调节细胞焦亡、Drp1 瓜氨酸依赖性线粒体功能以及肠和肝脏能量平衡在促进 MASH 中的作用，并表明 GSDME 可能是管理 MASH 的潜在治疗靶点。