Presentation Authors: Hsun Wang, Kaohsiung, Taiwan, Byung Oh, Bohan Wang, Yajun Ruan, Jun Zhou, Lia Banie, Arianna Tamaddon, Tie Zhou, Guifang Wang, Kelly Walker*, Guiting Lin, Tom Lue, San Francisco, CA
Introduction: Underactive bladder is a consequence of late-stage diabetes with decreased bladder contractility and increased post void residual urine. This study evaluates the therapeutic effect of once-per-week low-intensity extracorporeal shock wave therapy (Li-ESWT) on underactive bladder in the diabetic rat model.
Methods: Thirty-six female Sprague-Dawley rats were assigned into 3 groups: normal control (NC), diabetes control (DMC), and diabetes underwent Li-ESWT (DM Li-ESWT). The two DM groups received intraperitoneal streptozotocin to induce diabetes mellitus. Li-ESWT toward the pelvis of the rats was applied in DM Li-ESWT group once-per-week (0.02 mJ/mm2 at 3 Hz for 400 pulses) for 4 weeks. All rats were subjected to cystometry, leak point pressure, ex-vivo organ bath study, histology, western blot analysis, and immunofluorescence.
Results: Cystometry revealed significant improvement in the DM Li-ESWT group with reduced post-void residual urine (0.30 vs 0.91mL, p < 0.01), and increased leak point pressure (38.2 vs 31.3 cmH2O, p < 0.01) compared to DMC group. Ex-vivo organ bath study showed that Li-ESWT enhances muscle contractile activity of bladder in electrical field stimulation and drug stimulation. Histologically, Li-ESWT significantly restored bladder morphology- reducing intravesical lumen area and increasing muscle proportion. Western blot analysis showed higher smooth muscle actin expression in DM Li-ESWT compared to DMC group. Immunofluorescence demonstrated restored neuronal integrity and innervation in DM Li-ESWT group.
Conclusions: In conclusion, once-per-week Li-ESWT ameliorated the bladder function in the diabetic underactive bladder rat model. Li-ESWT improved bladder wall composition, activated bladder muscle regeneration, enhanced bladder muscle contractile function, increased bladder nerve innervation and promoted continence. Further investigations are encouraged for the potential clinical application.
Source of Funding: Support by NIDDK of the National Institutes of Health under award number R56DK105097 and 1R01DK105097-01A1.