Shi Yi, Huang Maoping, Zhou Wanmei, Zhao Yi, Zhao Jiuying, Zhong Bei, French Samuel W, Tang Xiaoping, Liu Hui
Precision Medicine Center, Department of Clinical Laboratory, The Fifth Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
The State Key Laboratory of Respiratory Disease and National Clinical Research Center for Respiratory Disease, Guangzhou, 510530, China.
J Transl Med. 2025 Jun 3;23(1):621. doi: 10.1186/s12967-025-06618-9.
Mallory-Denk bodies (MDBs) are characteristic proteins and inflammatory aggregates appeared in drug-induced chronic liver injury and various chronic liver disease. MDBs formation is often accompanied with mitochondrial damage and inflammatory environment. However, how mitochondrial damage and inflammatory response affect the pathological process of MDBs is largely unknown. The scope of this study was to provide unprecedented insights into the mechanism of MDBs pathogenesis and the potential target of transforming growth factor beta (TGF-β)/JNK axis in the treatment of MDB-related chronic liver disease.
Single-nucleus RNA sequencing (snRNA-seq), typical MDB-related multiplex immunofluorescence staining and functional in vitro and in vivo experiments were performed to investigate the potential mechanisms of TGF-β/JNK axis in the process of MDBs formation in chronic liver injury. Furthermore, the TGF-β/JNK axis has been demonstrated to be activated in clinical patients with metabolic dysfunction-associated steatotic liver disease (MASLD), which implies the potential clinical implications of the TGF-β/JNK axis.
Our study delineates a hepatocyte-macrophage crosstalk axis wherein TGF-β/TGF-βR dysregulation drives JNK-mediated MDBs pathogenesis. Mechanistically, the activation of JNK pathway upregulates downstream c-JUN expression (p < 0.0009, n = 3) and directly contributes to MDBs formation by promoting transcriptional activation of UbD. Concurrently, JNK signaling promotes BAX/BAK oligomerization, triggering mitochondrial translocation and subsequent generation of mitochondria-derived vesicles (MDVs), as evidenced by the significantly enhanced colocalization between damaged mtDNA and the mitochondrial outer membrane marker TOM20 in the experimental group compared to controls (p = 0.0001, n = 5). Then, following transport to macrophages, mtDNA escapes from MDVs, activating the cGAS-STING signaling and subsequently mediating IL-6 pro-inflammatory cytokine release (p = 0.0006, n = 3). Notably, the inhibition of JNK signaling attenuated both MDBs formation (p = 0.0027, n = 3) and IL-6 secretion (p = 0.0658, n = 3), demonstrating therapeutic potential through dual cytoprotective and immunomodulatory effects.
This study identifies the novel regulatory mechanism of the TGF-β/JNK signaling axis in MDBs formation, delivering mechanistic insights into MDB-associated chronic liver disease. Inhibition of JNK pathway suppresses MDBs formation while alleviates the inflammatory microenvironment by attenuating mitochondrial damage. Blocking the TGF-β/JNK signaling axis may represent a potential therapeutic strategy for MDB-associated chronic liver disease.
马洛里-登克小体（MDBs）是出现在药物性慢性肝损伤和各种慢性肝病中的特征性蛋白质和炎性聚集体。MDBs的形成常伴有线粒体损伤和炎症环境。然而，线粒体损伤和炎症反应如何影响MDBs的病理过程在很大程度上尚不清楚。本研究的目的是为MDBs发病机制以及转化生长因子β（TGF-β）/JNK轴在治疗与MDB相关的慢性肝病中的潜在靶点提供前所未有的见解。
进行单核RNA测序（snRNA-seq）、典型的与MDB相关的多重免疫荧光染色以及体外和体内功能实验，以研究TGF-β/JNK轴在慢性肝损伤中MDBs形成过程中的潜在机制。此外，TGF-β/JNK轴已被证明在代谢功能障碍相关脂肪性肝病（MASLD）临床患者中被激活，这暗示了TGF-β/JNK轴的潜在临床意义。
我们的研究描绘了一条肝细胞-巨噬细胞串扰轴，其中TGF-β/TGF-βR失调驱动JNK介导的MDBs发病机制。从机制上讲，JNK通路的激活上调下游c-JUN表达（p < 0.0009，n = 3），并通过促进UbD的转录激活直接促成MDBs的形成。同时，JNK信号促进BAX/BAK寡聚化，触发线粒体易位以及随后线粒体衍生囊泡（MDVs）的产生，与对照组相比，实验组中受损的线粒体DNA与线粒体外膜标记物TOM20之间的共定位显著增强证明了这一点（p = 0.0001，n = 5）。然后，在转运至巨噬细胞后，线粒体DNA从MDVs中逸出，激活cGAS-STING信号，随后介导IL-6促炎细胞因子释放（p = 0.0006，n = 3）。值得注意的是，JNK信号的抑制减弱了MDBs的形成（p = 0.0027，n = 3）和IL-6的分泌（p = 0.0658，n = 3），通过双重细胞保护和免疫调节作用证明了其治疗潜力。
本研究确定了TGF-β/JNK信号轴在MDBs形成中的新型调节机制，为与MDB相关的慢性肝病提供了机制性见解。抑制JNK通路可抑制MDBs的形成，同时通过减轻线粒体损伤来缓解炎症微环境。阻断TGF-β/JNK信号轴可能代表一种针对与MDB相关的慢性肝病的潜在治疗策略。
