Impregnation of implantable polypropylene mesh with S-nitrosoglutathione-loaded poly(vinyl alcohol)

Clinical complications of implantable polypropylene (PP) meshes used to repair urinary incontinence and vaginal prolapse may be associated with their low surface energy and consequent poor tissue integration. For improving tissue integration, we impregnated monofilament PP meshes with physically crosslinked poly(vinyl alcohol) (PVA), resulting in PVA deposits tightly attached inside the knot spaces of the PP knit. While preserving the mesh porosity, the PVA deposits acted as an array of hydrophilic regions leading to a great increase in the overall mesh wettability, reflected by a contact angle decrease from 111 to ca. 66°. The PVA deposits were also used as reservoirs for the local release of S-nitrosoglutathione (GSNO), a nitric oxide (NO) donor. Plain and impregnated PP meshes (1.0cm×1.0cm) were implanted in the subcutaneous tissue of 21 adult female Wistar rats. Histological analysis of the abdominal wall 21 days after the surgeries revealed lower edema and greater angiogenesis while a marked decrement of NOx concentration in the tissue surrounding the impregnated meshes was observed after 2 days. These results indicate that PVA and PVA/GSNO impregnation might be a new strategy for decreasing the frequency of mesh extrusion after PP mesh implants.