Vacuum therapy ameliorates erectile dysfunction in bilateral cavernous nerve crush rats by inhibiting apoptosis and activating autophagy

Abstract

Postprostatectomy erectile dysfunction (pPED) remains a current problem despite improvements in surgical techniques. Vacuum therapy is clinically confirmed as a type of pPED rehabilitation. However, its underlying mechanisms are incompletely understood. Recently, autophagy and apoptosis were extensively studied in erectile dysfunction resulting from diabetes, senescence, and androgen deprivation but not in the context of pPED and vacuum therapy. Therefore, this study was designed to investigate the roles of autophagy and apoptosis in pPED and vacuum therapy. Twenty-four adult male Sprague–Dawley rats were randomly divided into three groups: the control group, bilateral cavernous nerve crush (BCNC) group, and BCNC + vacuum group. After 4 weeks of treatment, intracavernosal pressure was used to evaluate erectile function. Real-time quantitative polymerase chain reaction, western blot, and immunohistochemistry were used to measure the molecular expression. TdT-mediated dUTP nick-end labeling staining was used to assess apoptosis. Transmission electron microscopy was used to observe autophagosomes. After treatment, compared with those of the BCNC group, erectile function and cavernosal hypoxia had statistically significantly improved (P < 0.05). Apoptosis and the relative protein expression of B-cell lymphoma-2-associated X and cleaved Caspase3 were decreased (P < 0.05). Autophagy-related molecules such as phosphorylated unc-51-like autophagy-activating kinase 1 (Ser757) and p62 were decreased. Beclin1, microtubule-associated protein 1 light chain 3 A/B, and autophagosomes were increased (P < 0.05). Besides, the phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin signaling pathway, as a negative regulator of autophagy to some degree, was inhibited. This study revealed that vacuum therapy ameliorated pPED in BCNC rats by inhibiting apoptosis and activating autophagy.

Keywords

• apoptosis; autophagy; bilateral cavernous nerve crush; erectile dysfunction; vacuum therapy