IL-17A exacerbates corpus cavernosum fibrosis and neurogenic erectile dysfunction by inducing CSMC senescence via the mTORC2-ACACA pathway.

ABSTRACT

BACKGROUND: Neurogenic erectile dysfunction, characterized by neurological repair disorders and progressive corpus cavernosum fibrosis (CCF), is an unbearable disease with limited treatment success. IL-17A exhibits a complex role in tissue remodelling. Nevertheless, the precise role and underlying mechanisms of IL-17A in CCF under denervation remain unclear. METHODS: PCR array was employed to identified differentially expressed genes between neurogenic ED and normal rats. IL-17A expression and its main target cells were analyzed using Western blotting, immunofluorescence and immunohistochemistry. The phenotypic regulation of IL-17A on corpus cavernosum smooth muscle cells (CSMCs) was evaluated by cell cycle experiments and SA-ß-Gal staining. The mechanism of IL-17A was elucidated using non-target metabolomics and siRNA technique. Finally, IL-17A antagonist and ABT-263 (an inhibitor of B-cell lymphoma 2/w/xL) were utilized to enhance the therapeutic effect in a rat model of neurogenic ED. RESULTS: IL-17A emerged as the most significantly upregulated gene in the corpus cavernosum of model rats. It augmented the senescence transformation and fibrotic response of CSMCs, and exhibited a strong correlation with CCF. Mechanistically, IL-17A facilitated CCF by activating the mTORC2-ACACA signalling pathway, upregulating of CSMCs lipid synthesis and senescence transition, and increasing the secretion of fibro-matrix proteins. In vivo, the blockade of IL-17A-senescence signalling improved erectile function and alleviated CCF in neurogenic ED. CONCLUSIONS: IL-17A assumes a pivotal role in denervated CCF by activating the mTORC2-ACACA signalling pathway, presenting itself as a potential therapeutic target for effectively overcoming CCF and erection rehabilitation in neurogenic ED.