The effect of adipose-derived stem cells on augmentation ileocystoplasty: A pilot study

OBJECTIVES: Incorporation of intestinal tissue into urinary tract elicits many metabolic and mechanical complications due to anatomical and physiological differences. Adipose-derived stem cells (ADSCs) improve vascularity and functional outcomes by a paracrine mechanism. In a pilot study we investigated whether ADSCs can survive in the augmented bladder and improve its function. MATERIALS AND METHODS: Autologous ADSCs were harvested from rat paragonadal fat and cultured before injection into a rat model of augmentation ileocystoplasty (study group). Control augmented bladders were injected with cell-free saline. Eight weeks later, rats underwent abdominal ultrasonography for upper tract changes and were examined by conscious cystometry to determine bladder function. After extirpation, augmented bladders were examined using Masson trichrome staining for connective tissue and muscle content, immunohistochemistry for α-smooth muscle actin, and rat endothelial cell antigen staining for endothelial cells. Changes in the extracellular matrix were assessed by determining the elastin content. ADSCs were labelled and tracked by 5-ethynyl-2-deoxyuridine nuclear staining. RESULTS: Abdominal ultrasonography showed better preservation of upper tract function in the ADSC group than in the saline-treated group (P = 0.007). After 2 months there were no differences in the variables assessed by conscious cystometry between the ADSC and saline-treated groups. However, the bladder weight was significantly greater in the ADSC-treated group. On immunohistochemistry, the implanted ADSCs survived up to 8 weeks but did not transdifferentiate into smooth muscle or endothelial cells. CONCLUSION: These results suggested a potential role of ADSCs in modifying the intestinal segment in augmented bladders; this role has to be further elucidated.