Department of Urology, The Fifth Affiliated Hospital of Sun Yat-Sen University, Zhuhai, Guangdong, China.
Guangdong Provincial Key Laboratory of Biomedical Imaging, The Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, Guangdong, China.
CNS Neurosci Ther. 2023 Nov;29(11):3239-3258. doi: 10.1111/cns.14256. Epub 2023 May 8.
Clinical treatment of erectile dysfunction (ED) caused by cavernous nerve (CN) injury during pelvic surgery is difficult. Low-intensity pulsed ultrasound (LIPUS) can be a potential strategy for neurogenic ED (NED). However, whether Schwann cells (SCs) can respond to LIPUS stimulation signals is unclear. This study aims to elucidate the signal transmission between SCs paracrine exosome (Exo) and neurons stimulated by LIPUS, as well as to analyze the role and potential mechanisms of exosomes in CN repair after injury.
The major pelvic ganglion (MPG) neurons and MPG/CN explants were stimulated with LIPUS of different energy intensities to explore the appropriate LIPUS energy intensity. The exosomes were isolated and purified from LIPUS-stimulated SCs (LIPUS-SCs-Exo) and non-stimulated SCs (SCs-Exo). The effects of LIPUS-SCs-Exo on neurite outgrowth, erectile function, and cavernous penis histology were identified in bilateral cavernous nerve crush injury (BCNI)-induced ED rats.
LIPUS-SCs-Exo group can enhance the axon elongation of MPG/CN and MPG neurons compared to SCs-Exo group in vitro. Then, the LIPUS-SCs-Exo group showed a stronger ability to promote the injured CN regeneration and SCs proliferation compared to the SCs-Exo group in vivo. Furthermore, the LIPUS-SCs-Exo group increased the Max intracavernous pressure (ICP)/mean arterial pressure (MAP), lumen to parenchyma and smooth muscle to collagen ratios compared to the SCs-Exo group in vivo. Additionally, high-throughput sequencing combined with bioinformatics analysis revealed the differential expression of 1689 miRNAs between the SCs-Exo group and the LIPUS-SCs-Exo group. After LIPUS-SCs-Exo treatment, the phosphorylated levels of Phosphatidylinositol 3-kinase (PI3K), protein kinase B (Akt) and forkhead box O (FoxO) in MPG neurons increased significantly compared to negative control (NC) and SCs-Exo groups.
Our study revealed that LIPUS stimulation could regulate the gene of MPG neurons by changing miRNAs derived from SCs-Exo, then activating the PI3K-Akt-FoxO signal pathway to enhance nerve regeneration and restore erectile function. This study had important theoretical and practical significance for improving the NED treatment.
骨盆手术中海绵体神经（CN）损伤导致的勃起功能障碍（ED）的临床治疗较为困难。低强度脉冲超声（LIPUS）可能是治疗神经源性 ED（NED）的一种潜在策略。然而，雪旺细胞（SCs）是否能对 LIPUS 刺激信号做出反应尚不清楚。本研究旨在阐明 LIPUS 刺激SCs 旁分泌外泌体（Exo）与神经元之间的信号传递，以及分析外泌体在 CN 损伤后的修复中的作用和潜在机制。
用不同能量强度的 LIPUS 刺激主要骨盆神经节（MPG）神经元和 MPG/CN 外植体，以探讨合适的 LIPUS 能量强度。从 LIPUS 刺激的SCs（LIPUS-SCs-Exo）和未刺激的SCs（SCs-Exo）中分离和纯化外泌体。在双侧海绵体神经挤压损伤（BCNI）诱导的 ED 大鼠中，研究 LIPUS-SCs-Exo 对神经突生长、勃起功能和海绵体阴茎组织学的影响。
与SCs-Exo 组相比，LIPUS-SCs-Exo 组在体外能增强 MPG/CN 和 MPG 神经元的轴突伸长。然后，与SCs-Exo 组相比，LIPUS-SCs-Exo 组在体内能更强地促进受损 CN 的再生和SCs 的增殖。此外，与SCs-Exo 组相比，LIPUS-SCs-Exo 组能增加 Max 海绵体内压（ICP）/平均动脉压（MAP）、管腔与实质比和平滑肌与胶原比。此外，高通量测序结合生物信息学分析显示，SCs-Exo 组和 LIPUS-SCs-Exo 组之间有 1689 个 miRNA 的差异表达。与阴性对照（NC）和SCs-Exo 组相比，LIPUS-SCs-Exo 处理后 MPG 神经元中磷酸化的磷脂酰肌醇 3-激酶（PI3K）、蛋白激酶 B（Akt）和叉头框 O（FoxO）水平显著升高。
本研究表明，LIPUS 刺激通过改变源自SCs-Exo 的 miRNA 来调节 MPG 神经元的基因，然后激活 PI3K-Akt-FoxO 信号通路，增强神经再生，恢复勃起功能。这项研究对改善 NED 治疗具有重要的理论和实际意义。
