Hata Shinro, Shinohara Mayuka, Mimata Hiromitsu, Shin Toshitaka
Department of Urology, Oita University Faculty of Medicine, Yufu, Oita, Japan.
Physiol Rep. 2025 Mar;13(5):e70265. doi: 10.14814/phy2.70265.
Urinary incontinence increases with age, reducing the elderly quality of life. Understanding its mechanisms and developing treatments are urgent tasks. While healthy striated muscle maintains homeostasis through mitophagy, aging is thought to reduce autophagy activity. This study aimed to detect abnormal mitochondrial accumulation in the rhabdosphincter using transmission electron microscopy (TEM). We collected the rhabdosphincter samples from seven patients undergoing cystectomy and used the rectus abdominis as controls. Both tissues were examined with Hematoxylin and eosin (HE) staining and TEM. ImageJ software was used to measure the mitochondrial area, perimeter, and luminance. HE staining revealed that the rhabdosphincter had fewer muscle fibers and more stromal tissue than the rectus abdominis. TEM images showed more gaps in muscle bundles and signs of mitochondrial damage, vacuolation, and swelling in the rhabdosphincter. Quantitative analysis revealed a larger average mitochondrial area (0.21 μm vs. 0.063 μm, p < 0.01), longer perimeter (1.83 μm vs. 0.94 μm, p < 0.01) and higher luminance (156.6 vs. 90.2, p < 0.01) than those of the rectus abdominis. The rhabdosphincter of elderly individuals showed significant mitochondrial morphological abnormalities, with increased swelling and vacuolation.
尿失禁随年龄增长而增加，降低了老年人的生活质量。了解其机制并开发治疗方法是紧迫的任务。健康的横纹肌通过线粒体自噬维持体内平衡，而衰老被认为会降低自噬活性。本研究旨在使用透射电子显微镜（TEM）检测尿道外括约肌中线粒体的异常积聚。我们收集了7例接受膀胱切除术患者的尿道外括约肌样本，并以腹直肌作为对照。对两种组织进行苏木精-伊红（HE）染色和TEM检查。使用ImageJ软件测量线粒体的面积、周长和亮度。HE染色显示，与腹直肌相比，尿道外括约肌的肌纤维较少，间质组织较多。TEM图像显示尿道外括约肌的肌束间隙更多，并有线粒体损伤、空泡化和肿胀的迹象。定量分析显示，尿道外括约肌的平均线粒体面积更大（0.21μm对0.063μm，p<0.01），周长更长（1.83μm对0.94μm，p<0.01），亮度更高（156.6对90.2，p<0.01）。老年人的尿道外括约肌显示出线粒体形态明显异常，肿胀和空泡化增加。
