Is the poly (L- lactide- co- caprolactone) nanofibrous membrane suitable for urinary bladder regeneration?

The purpose of this study was to compare: a new five-layered poly (L-lactide-co-caprolactone) (PLC) membrane and small intestinal submucosa (SIS) as a control in rat urinary bladder wall regeneration. The five-layered poly (L-lactide-co-caprolactone) membrane was prepared by an electrospinning process. Adipose tissue was harvested from five 8-week old male Wistar rats. Adipose derived stem cells (ADSCs) were seeded in a density of 3×10(6) cells/cm2 onto PLC membrane and SIS scaffolds, and cultured for 5-7 days in the stem cell culture medium. Twenty male Wistar rats were randomly divided into five equal groups. Augmentation cystoplasty was performed in a previously created dome defect. Groups: (I) PLC+ 3×10(6)ADSCs; (II) SIS+ 3×10(6)ADSCs; (III) PLC; (IV) SIS; (V) control. Cystography was performed after three months. The reconstructed urinary bladders were evaluated in H&E and Masson's trichrome staining. Regeneration of all components of the normal urinary bladder wall was observed in bladders augmented with cell-seeded SIS matrices. The urinary bladders augmented with SIS matrices without cells showed fibrosis and graft contraction. Bladder augmentation with the PLC membrane led to numerous undesirable events including: bladder wall perforation, fistula or diverticula formation, and incorporation of the reconstructed wall into the bladder lumen. The new five-layered poly (L-lactide-co-caprolactone) membrane possesses poorer potential for regenerating the urinary bladder wall compared with SIS scaffold

Contact angle measurements: untreated poly (lactydo-<i>co</i>-caprolactone) (PLC) membrane, 110° (A), NaHCO₃ treated PLC membrane: unmodified side- 97° (C) and modified side- 72° (B).

<p>Contact angle is the angle between the baseline of the drop (marked in red) and the tangent at the drop boundary (marked in yellow).</p

Analysis of poly (lactydo-<i>co</i>-caprolactone) (PLC) and small intestinal submucosa (SIS) cytotoxicity using Real Time Cell Analyzer (RTCA).

<p>Adipose derived stem cells were treated with 75%, 50% and 25% extracts of PLC (PLC75, PLC50, PLC25 respectively) and SIS (SIS75, SIS50, SIS25 respectively). The results are presented as: cell growth curves (A), mean cell index ± standard deviation after 96 hours of cell incubation with extracts. The statistical significance is shown as * p<0.05 (B)</p

Cystography.

<p>Urinary bladders augmented with poly (lactydo-<i>co</i>-caprolactone) membrane (A) and small intestinal submucosa seeded with adipose derived stem cells (B). The arrows point out the reconstructed area.</p

Bladders augmented with poly (lactydo-<i>co</i>-caprolactone) membrane seeded (A,B) and unseeded (C,D) with adipose derived stem cells.

<p>Light microscope, H&E (A,C) and Trichrome Masson staining (B,D), bar = 500 µm.</p

Bladders augmented with small intestinal submucosa seeded (A,B) and unseeded (C,D) with adipose derived stem cells.

<p>Native bladders in control group (E,F). Light microscope, H&E (A,C,E) and Trichrome Masson staining (B,D,F), bar = 200 µm.</p