Imaging and Molecular Mechanisms of Pelvic Floor Electrical Stimulation in Improving Pelvic Floor Muscle Injury in Stress Urinary Incontinence Rats

Results: PFES significantly elevated ALPP compared with controls, indicating improved urinary continence. MRI demonstrated that PFES attenuated focal hyperintensity, muscle edema, and fiber disorganization in the pubococcygeus muscle. Histological analyses confirmed that PFES restored dense muscle fiber arrangement and collagen distribution, and immunohistochemistry showed upregulated expression of COL1A1, COL3A1, and CD34.

RNA-seq revealed that differentially expressed genes were prominently enriched in ECM organization, focal adhesion, ECM-receptor interaction, and the PI3K-Akt pathway. Western blotting verified that PFES increased COL1A1, COL3A1, and VEGFA, while suppressing the atrophy-related ubiquitin ligase FBXO32. Conclusion: PFES effectively repairs pelvic floor muscle structure and function by reducing muscle edema and fiber disruption, upregulating type I and III collagens to promote ECM remodeling, inducing VEGF-mediated angiogenesis, and downregulating FBXO32 to counteract atrophy.

These findings elucidate PFES mechanisms and support its clinical application.