Subramanian Bhuvaneshwaran, Johnson Shedreanna, Narayanan Akshaya, Wang Wei, Seaberg Bonnie L, Ball Jillian, Paredes Mares Ilse M, Majumder Ahana, Aceves Alexandria, Frazier Sarah E, Rutledge Alexis, Griffin John F, Pal Soumiya, Zawieja Scott, Davis Michael J, Rutkowski Joseph M, Nghiem Peter P, Rimer Mendell, Muthuchamy Mariappan
Department of Medical Physiology, Naresh K. Vashisht College of Medicine, Texas A&M University, Bryan, TX 77807.
Department of Neuroscience and Experimental Therapeutics, Naresh K. Vashisht College of Medicine, Texas A&M University, Bryan, TX 77807.
Proc Natl Acad Sci U S A. 2025 Sep 23;122(38):e2505656122. doi: 10.1073/pnas.2505656122. Epub 2025 Sep 18.
Duchenne muscular dystrophy (DMD) is a severe muscle-wasting disorder characterized by progressive muscle weakness and inflammation caused by mutations in the DMD gene. Chronic inflammation in DMD exacerbates the complications associated with disease progression. Since the lymphatic system plays a crucial role in regulating and resolving inflammation, our primary goal was to investigate whether lymphatics were dysregulated in skeletal muscle of DMD animals. We used the murine and golden retriever muscular dystrophy (GRMD) canine models, as well as mouse and rat lymphatic muscle cells (LMCs) to determine the role of dystrophin in lymphatic structure and function in skeletal muscles. Single-cell RNA sequencing data from control LMCs showed dystrophin expression, and protein results demonstrated that the 427-, 140-, and 71-kDa dystrophin isoforms were detectable in the LMCs from control mice, whereas the 427 kDa isoform was undetectable in LMCs derived from mice. Microlymphangiography and magnetic resonance lymphangiogram results showed a significant decrease in lymph transport in D2. mice and GRMD dogs, respectively. Isolated flank lymphatic vessels from D2. mice exhibited an increase in tonic contraction and a significant decrease in the phasic contractile frequency and amplitude, supporting lymphatic vessel dysfunction. The gene expression profile and immunofluorescence analyses of dystrophic muscle revealed inflammatory lymphangiogenesis in dystrophic muscle. Skeletal muscle tissues that showed improvement in function after adeno-associated virus-microdystrophin treatment also showed significant improvement in inflammatory lymphangiogenesis in GRMD dogs. Thus, these results show a linkage between lymphatic function and DMD pathogenesis that merits further investigation in DMD patients.
杜兴氏肌肉营养不良症（DMD）是一种严重的肌肉萎缩性疾病，其特征是由DMD基因突变导致进行性肌肉无力和炎症。DMD中的慢性炎症会加剧与疾病进展相关的并发症。由于淋巴系统在调节和解决炎症方面起着关键作用，我们的主要目标是研究DMD动物骨骼肌中的淋巴管是否失调。我们使用了小鼠和金毛猎犬肌肉营养不良症（GRMD）犬模型，以及小鼠和大鼠的淋巴管肌肉细胞（LMCs）来确定肌营养不良蛋白在骨骼肌淋巴管结构和功能中的作用。来自对照LMCs的单细胞RNA测序数据显示了肌营养不良蛋白的表达，蛋白质结果表明，在对照小鼠的LMCs中可检测到427 kDa、140 kDa和71 kDa的肌营养不良蛋白异构体，而在来自 小鼠的LMCs中未检测到427 kDa异构体。微淋巴管造影和磁共振淋巴管造影结果分别显示D2.小鼠和GRMD犬的淋巴运输显著减少。从D2.小鼠分离的胁腹淋巴管表现出强直性收缩增加，相性收缩频率和幅度显著降低，支持淋巴管功能障碍。营养不良肌肉的基因表达谱和免疫荧光分析显示营养不良肌肉中存在炎性淋巴管生成。在腺相关病毒-微肌营养不良蛋白治疗后功能有所改善的骨骼肌组织在GRMD犬中也显示出炎性淋巴管生成的显著改善。因此，这些结果表明淋巴功能与DMD发病机制之间存在联系，值得在DMD患者中进一步研究。
