Department of Medical Ultrasound, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai, China.
Shanghai Key Laboratory of Vascular Lesions Regulation and Remodeling, Shanghai Pudong Hospital, Fudan University Pudong Medical Center, Shanghai, China.
Ultrasound Med Biol. 2023 Nov;49(11):2336-2345. doi: 10.1016/j.ultrasmedbio.2023.07.010. Epub 2023 Aug 4.
Two-dimensional shear wave elastography (2-D SWE) has been proven to detect hyperlipidemia-induced elastic abnormality in the corpus cavernosum. This study investigated cytological factors affecting the elasticity of the corpus cavernosum in rabbits with hyperlipidemia using single-cell RNA sequencing (scRNA-seq).
Male New Zealand white rabbits were randomly divided into a hyperlipidemia group (high-cholesterol diet) and a control group (standard diet). Penile 2-D SWE was performed to detect the elastic abnormality in the corpus cavernosum. ScRNA-seq was performed to observe cellular changes in the corpus cavernosum of rabbits with hyperlipidemia. Immunohistochemistry, immunofluorescence and histological examinations were conducted to verify the results of scRNA-seq.
Two-dimensional SWE revealed that the Young's modulus of the corpus cavernosum was significantly greater in the hyperlipidemia group than that in the control group (p < 0.001). Histological findings revealed extracellular matrix accumulation within the corpus cavernosum, with stronger staining of collagen types I and Ⅲ. ScRNA-seq revealed that fibroblasts, smooth muscle cells, and endothelial cells were the major cell types in the corpus cavernosum. A novel subtype of fibroblasts (myofibroblast) was discovered in the hyperlipidemia group, which was verified by immunofluorescence staining and gene ontology analysis. Fibroblasts, smooth muscle cells and endothelial cells were three cellular sources for myofibroblasts.
Myofibroblasts are activated and proliferate and secrete large amounts of collagen fibers in the corpus cavernosum during hyperlipidemia, leading to abnormal Young's modulus detected by 2-D SWE and their recognition as a new factor affecting the hyperlipidemia-induced elastic abnormality of the corpus cavernosum.
二维剪切波弹性成像（2-D SWE）已被证明可检测出高脂血症引起的海绵体弹性异常。本研究通过单细胞 RNA 测序（scRNA-seq）研究了高脂血症兔海绵体弹性的细胞学影响因素。
雄性新西兰白兔随机分为高脂血症组（高胆固醇饮食）和对照组（标准饮食）。行阴茎 2-D SWE 检测海绵体弹性异常。行 scRNA-seq 观察高脂血症兔海绵体的细胞变化。免疫组化、免疫荧光和组织学检查验证 scRNA-seq 的结果。
2-D SWE 显示高脂血症组的海绵体杨氏模量明显大于对照组（p<0.001）。组织学发现海绵体中有细胞外基质积聚，胶原 I 和 III 型染色较强。scRNA-seq 显示成纤维细胞、平滑肌细胞和内皮细胞是海绵体的主要细胞类型。在高脂血症组发现了一种新型成纤维细胞（肌成纤维细胞），免疫荧光染色和基因本体分析验证了这一点。成纤维细胞、平滑肌细胞和内皮细胞是肌成纤维细胞的三个细胞来源。
高脂血症时，海绵体中成纤维细胞被激活、增殖并分泌大量胶原纤维，导致 2-D SWE 检测到异常杨氏模量，并将其视为影响海绵体弹性异常的新因素。
