Transplantation of Allogenic Adipose-Derived Stem Cell Improve Urethral Muscle-Collagen Ratio After Vaginal Distension

Objective: To investigate the effects of allogenic adipose-derived stem cell (ADSC) transplantation on urethral tissue regeneration after vaginal distension in a rat model. Material & Method: 32 female wistar rats underwent vaginal distension (VD) for 4 h. Subsequently, PKH-labeled ADSCs (2 x 105 in 200 µl PBS, ADSC group, n = 18) or PBS (200 µl, placebo group, n = 18) were injected into periurethral tissue. Two and four weeks following transplantation (ADSC or PBS), voiding behavior (frequency) and muscle-collagen ratio of urethral tissue were measured to evaluate urethral sphincter regeneration. Data were analysed by paired-t test, one-way ANOVA and post hoc LSD. Results: Mean voiding frequency was significantly different in the ADSC group at two weeks (p < 0.0001), but not significantly different at four weeks (p = 0,448) when compared with the placebo group. Masson’s trichrome staining revealed that the muscle-collagen ratio of urethral tissue was not significantly different between study groups at two or four weeks (p = 0.053 or p = 0.166 respectively). Muscle-urethral ratio was more specific showing a significant difference at two weeks (p = 0.043). There were significant differences about muscle-collagen or muscle-urethral ratio between control and placebo groups (p < 0.05), where as between control and ADSC groups no significant difference was observed (p > 0.05). Conclusion: ADSC transplantation promotes urethral muscle-collagen ratio with development of striated muscle after vaginal distension, so that can improve voiding behavior in a rat model. Keywords: Adipose-derived stem cell, vaginal distension, rat-SUI model, muscle-collagen ratio, voiding stain on paper.