Exosomes Derived by SIRT1-Overexpressing Bone Marrow Mesenchymal Stem Cells Improve Pubococcygeus Muscle Injury in Rats.

Background and Objectives To evaluate the effect of exosomes (Exos) derived from silent mating type information regulation 2 homolog 1 (SIRT1)-overexpressing human bone marrow mesenchymal stem cells (BMSCs) on the recovery of pubococcygeus muscle Injury. Methods and Results Exos isolated from SIRT1-overexpressing BMSCs (SIRT1/exos) were injected into a vaginal dilation-induced rat model of Stress urinary incontinence (SUI). The efficacy of Exos treatment on SUI was evaluated by determining the values of urodynamic parameters. The proliferation and differentiation of satellite cells (SCs) were examined by CCK-8 assay, Western blotting, and immunofluorescence staining. The mRNA and protein expression of molecules related to SC differentiation were detected by RT-qPCR and Western blotting, respectively. Treatment with SIRT1/exos significantly improved the values of abdominal leak point pressure (ALPP), maximum bladder volume (MBV), and estimated marginal mean in rats of SUI. Exposure of SIRT1/exos enhanced the proliferation, differentiation, and activation of SCs. Moreover, SIRT1/exos exhibited their positive effect on BMSCs by activating the ERK signaling. Conclusions Our findings demonstrated that SIRT1/exos meliorated pubococcygeus muscle injury in rats by promoting ERK pathway, which may provide a novel cell-free therapeutic strategy for SUI.