Impact of Prolapse Meshes on the Metabolism of Vaginal Extracellular Matrix in Rhesus Macaque

Abstract

Objective-The impact of polypropylene mesh implantation on vaginal collagen and elastin metabolism was analyzed using a nonhuman primate model to further delineate the mechanism of mesh induced complications.Methods-49 middle aged parous rhesus macaques underwent surgical implantation of 3 synthetic meshes via sacrocolpopexy. Gynemesh PS (n=12) and two lower weight, higher porosity, lower stiffness meshes -UltraPro (n = 19) and Restorelle (n=8) were implanted, in which UltraPro was implanted with its blue orientation lines perpendicular (low stiffness direction, n=11) and parallel (high stiffness direction, n=8) to the longitudinal axis of vagina. Sham operated animals were used as controls (n=10). Twelve weeks after surgery, the meshtissue complex was excised and analyzed.Results-Relative to Sham, Gynemesh PS had a negative impact on the metabolism of both collagen and elastin favoring catabolic reactions while UltraPro only induced an increase in elastin degradation. Restorelle had the least impact. As compared to Sham, the degradation of collagen and elastin in the vagina implanted with Gynemesh PS was increased with a simultaneous increase in active MMP-1, -8, -13 and total MMP-2, -9 (all P<0.05). The degradation of elastin (tropoelastin and mature elastin) was increased in the UltraPro implanted vagina with a concomitant increase of MMP-2, and -9 (all P<0.05). Collagen subtype ratio III/I was increased in both Gynemesh PS and UltraPro perpendicular groups (P<0.05). Condensation:The heavier, less porous and stiffer mesh Gynemesh PS increased the catabolism of collagen and elastin in the vagina, characterized by increased matrix degradation and MMPs.Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Conclusion-Following implantation with the heavier, less porous and stiffer mesh, Gynemesh PS, the degradation of vaginal collagen and elastin exceeded synthesis, most likely as a result of increased activity of MMPs, resulting in a structurally compromised tissue. NIH Public Access

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