Low‐intensity pulsed ultrasound ameliorates erectile dysfunction induced by bilateral cavernous nerve injury through enhancing Schwann cell‐mediated cavernous nerve regeneration

Abstract

Background Cavernous nerve injury‐induced erectile dysfunction caused by pelvic surgery or trauma is refractory to conventional medications and required an alternative treatment. Low‐intensity pulsed ultrasound is a noninvasive mechanical therapy that promotes nerve regeneration. Objectives To investigate the therapeutic effect and potential mechanism of low‐intensity pulsed ultrasound in the treatment of neurogenic erectile dysfunction. Materials and methods Thirty rats were randomly divided into the sham‐operated group, bilateral cavernous nerve injury group, and bilateral cavernous nerve injury + low‐intensity pulsed ultrasound group. The erectile function was assessed 3 weeks after daily low‐intensity pulsed ultrasound treatment. The penile tissues and cavernous nerve tissues were harvested and subjected to histologic analysis. Primary Schwann cells and explants were extracted from adult rats. The effects of low‐intensity pulsed ultrasound on proliferation, migration, and nerve growth factor expression of Schwann cells and axonal elongation were examined in vitro. RNA sequencing and western blot assay were applied to predict and verify the molecular mechanism of low‐intensity pulsed ultrasound‐induced Schwann cell activation. Results Our study showed that low‐intensity pulsed ultrasound promoted Schwann cells proliferation, migration, and neurotrophic factor nerve growth factor expression. Meanwhile, low‐intensity pulsed ultrasound exhibits a stronger ability to enhance Schwann cells‐mediated neurite outgrowth of major pelvic ganglion neurons and major pelvic ganglion/cavernous nerve explants in vitro. In vivo experiments demonstrated that the erectile function of the rats in the bilateral cavernous nerve injury + low‐intensity pulsed ultrasound group was significantly higher than those in the bilateral cavernous nerve injury groups. Moreover, the expression levels of smooth muscle and cavernous endothelium also increased significantly in the bilateral cavernous nerve injury + low‐intensity pulsed ultrasound group. In addition, we observed the higher density and number of cavernous nerve regenerating axons in the bilateral cavernous nerve injury + low‐intensity pulsed ultrasound group, indicating that low‐intensity pulsed ultrasound promotes axonal regeneration following cavernous nerve injury in vivo. RNA sequencing analysis and bioinformatic analysis suggested that low‐intensity pulsed ultrasound might trigger the activation of the PI3K/Akt pathway. Western blot assay confirmed that low‐intensity pulsed ultrasound activated Schwann cells through TrkB/Akt/CREB signaling. Conclusions Low‐intensity pulsed ultrasound promoted nerve regeneration and ameliorated erectile function by enhancing Schwann cells proliferation, migration, and neurotrophic factor nerve growth factor expression. The TrkB/Akt/CREB axis is the possible mechanism of low‐intensity pulsed ultrasound‐mediated Schwann cell activation. Low‐intensity pulsed ultrasound‐based therapy could be a novel potential treatment strategy for caverno...

Knowledge mapping and global trends in the field of low-intensity pulsed ultrasound and endocrine and metabolic diseases: a bibliometric and visual analysis from 2012 to 2022

“…found that LIPUS could increase testosterone levels in animal models and alleviate Leydig cell aging in vitro ( 51 ). Furthermore, combining LIPUS with tadalafil effectively treats erectile dysfunction in patients with type 2 diabetes ( 52 ), and promotes nerve regeneration and improves erectile function by enhancing Schwann cell proliferation, migration, and expression of neurotrophic factors such as nerve growth factor ( 53 ). In terms of bone metabolism, Wu et al.…”

New developments in erectile dysfunction treatments: A role for regenerative medicine

“…Ectoderm, mesoderm, and endoderm are the three germ cells that can be differentiated from iPSCs, similar to ESCs, in contrast to MSCs, which can only differentiate into a limited number of cell lines [86]. Increases in ICP/MAP, eNOS, and S100β content in MPG can be achieved by employing iPSCs to repair cavernous nerve integrity [87].…”