Zheng Cheng, Huang Jianmin, Xu Shengming, Lu Bin, Que Hanxin, Chen Tianhao, Hou Yubo, He Linlin, Fan Xia, Chen Fa-Ming, Wang Yi, Deng Hui
Institute of Stomatology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, Zhejiang, China.
Department of Periodontology, School and Hospital of Stomatology, Wenzhou Medical University, Wenzhou, Zhejiang, China.
Front Cell Infect Microbiol. 2025 Aug 8;15:1613366. doi: 10.3389/fcimb.2025.1613366. eCollection 2025.
The direct infection of endothelial cells by (), a keystone periodontal pathogen, has been implicated in the development of atherosclerosis. While non-selective autophagy facilitates its intracellular persistence in endothelial cells, the role of selective autophagy in this process remains unclear. This study investigated whether hijacks mitophagy and lysosomes to persist in endothelial cells.
Human aortic endothelial cells (HAECs) were infected with for 24 h. Mitophagy was detected by Western Blotting (WB), immunofluorescence, and transmission electron microscopy. Lysosomal function was assessed by acridine orange staining, lysosensor staining, and WB. The effects of mitophagy and lysosomes on intracellular survival were evaluated by antibiotic protection assays and SYTO-9 staining.
Our data demonstrated that initiates PTEN-induced putative kinase 1 (PINK1)-Parkin-mediated mitophagy in HAECs, leading to increased formation of autophagosomes and mitophagosomes, but disrupted autophagy/mitophagy flux. This blockage of autophagy/mitophagy flux was linked to lysosomal dysfunction, characterized by increased lysosome number, lysosomal membrane permeabilization, disruption of the lysosomal acidic environment, and decreased enzymatic activity. Additionally, antibiotic protection assays and SYTO-9 staining further revealed that promotes its intracellular survival in endothelial cells by initiating mitophagy and impairing lysosomal function. Furthermore, the mitophagy activator decreased the co-localization of with microtubule-associated protein 1 light chain 3 (LC3)-p62, LC3-NDP52, and lysosomal-associated membrane protein 1 (LAMP1), suggesting that -initiated mitophagy inhibited xenophagosome formation and autophagosome/xenophagosome-lysosome fusion.
Our findings reveal that may promote its intracellular survival in endothelial cells by initiating PINK1-Parkin-mediated mitophagy and impairing lysosomal function, thereby suppressing xenophagosome formation and xenophagic degradation. This study provides new insights into the mechanisms by which persists in endothelial cells and its potential role in atherosclerosis progression.
主要牙周病原体牙龈卟啉单胞菌(Porphyromonas gingivalis)对内皮细胞的直接感染与动脉粥样硬化的发展有关。虽然非选择性自噬促进其在内皮细胞中的细胞内持续存在,但选择性自噬在此过程中的作用仍不清楚。本研究调查了牙龈卟啉单胞菌是否劫持线粒体自噬和溶酶体以在内皮细胞中持续存在。
用人主动脉内皮细胞(HAECs)感染牙龈卟啉单胞菌24小时。通过蛋白质免疫印迹法(WB)、免疫荧光和透射电子显微镜检测线粒体自噬。通过吖啶橙染色、溶酶体传感器染色和WB评估溶酶体功能。通过抗生素保护试验和SYTO-9染色评估线粒体自噬和溶酶体对牙龈卟啉单胞菌细胞内存活的影响。
我们的数据表明,牙龈卟啉单胞菌在HAECs中引发PTEN诱导的假定激酶1(PINK1)-帕金蛋白介导的线粒体自噬,导致自噬体和线粒体自噬体形成增加,但破坏了自噬/线粒体自噬通量。这种自噬/线粒体自噬通量的阻断与溶酶体功能障碍有关,其特征是溶酶体数量增加、溶酶体膜通透性增加、溶酶体酸性环境破坏和酶活性降低。此外,抗生素保护试验和SYTO-9染色进一步表明,牙龈卟啉单胞菌通过引发线粒体自噬和损害溶酶体功能来促进其在内皮细胞中的细胞内存活。此外,线粒体自噬激活剂减少了牙龈卟啉单胞菌与微管相关蛋白1轻链3(LC3)-p62、LC3-NDP52和溶酶体相关膜蛋白1(LAMP1)的共定位,表明牙龈卟啉单胞菌引发的线粒体自噬抑制了异噬小体的形成以及自噬体/异噬小体-溶酶体融合。
我们的研究结果表明,牙龈卟啉单胞菌可能通过引发PINK1-帕金蛋白介导的线粒体自噬和损害溶酶体功能来促进其在内皮细胞中的细胞内存活,从而抑制异噬小体的形成和异噬性降解。本研究为牙龈卟啉单胞菌在内皮细胞中持续存在的机制及其在动脉粥样硬化进展中的潜在作用提供了新的见解。