Transplantation of adipose tissue-derived stem cell-derived exosomes ameliorates erectile function in diabetic rats

Mesenchymal stem cells (MSCs) have been considered as an attractive tool for the therapy of diseases. Accumulating evidence indicates that the healing effects of MSCs are mainly related to paracrine action rather than transdifferentiation. Exosomes excreted from MSCs have emerged as physiologically relevant and powerful components of the MSC secretome. However, whether MSC-derived exosomes can improve erectile function of streptozotocin-induced diabetic rats and its mechanism remains unknown. Our previous work showed that adipose tissue-derived stem cells (ADSCs) transplantation could increase endothelial and smooth muscle contents and improve erectile function of diabetic rats. In this study, ADSC-derived exosomes (ADSC-Exo) exhibited in vitro proangiogenic properties, induced the proliferation of endothelial cells and restored erectile function in vivo, as well as decreased fibrosis of corpus cavernosum. In further experiments, we found that ADSC-Exo contained some proangiogenic (miR-126, miR-130a and miR-132) microRNAs and an antifibrotic microRNA family (miR-let7b and miR-let7c). Thus, it is reasonable to postulate that ADSC-Exo transports key functional miRNAs to target cells in a specific manner to improve functional recovery or to activate endogenous repair mechanisms. This proof-of-concept study provides a novel approach for the treatment of diabetic erectile dysfunction.