Self-gripping versus polypropylene mesh for incisional hernia repair in a rat model

BackgroundSelf-gripping mesh, made of monofilament polypropylene and covered by a layer of polylactic acid micro-hooks, is applied in ventral hernia repair, whereas cytological change and collagen expression around the mesh are rarely reported. The objective of this research was to compare inflammatory response and collagen proliferation between self-gripping and polypropylene mesh in rat model of incisional hernia.MethodsForty-five rats were randomly divided into unrepaired (UR) group, polypropylene (PP) mesh group, and self-gripping (SG) mesh group and euthanized at 1, 2 and 4 weeks postoperatively. The levels of inflammation, neovascularization, and collagen expression were measured by immunohistochemistry, quantitative real-time polymerase chain reaction, and Western blot.ResultsOne rat died and others developed typical incisional hernia in UR group, and hematoma, seroma, or wound infection were not observed in PP and SG groups. There was no significant difference in mesh shrinkage and inflammatory infiltration between PP and SG groups. With regard to neovascularization, 2 groups were comparable at 1 and 2 weeks, while the neovascularization score of PP group was statistically higher than that of SG group at 4 weeks. One week after surgery, the amounts of Collagen I (Col I) mRNA in PP group were significantly higher than SG group, while the amounts of Collagen III (Col III) mRNA were comparable between 2 groups. Two weeks following operation, the expressions of Col I mRNA and Col III mRNA in PP group were statistically lower than those in SG group. Four weeks postoperatively, the levels of Col I mRNA and Col III mRNA in PP group were significantly higher than those in SG group.ConclusionSelf-gripping mesh induced comparable inflammatory response and collagen proliferation compared with polypropylene mesh in a rat model. Registration number: ZZU-LAC2023080121.