Functional biopolymer-based matrices for modulation of chronic wound enzyme activities

摘要

Collagen, collagen/hyaluronic acid (HA) and collagen/HA/chitosan (CS) sponges loaded with epigallocatechingallate (EGCG), catechin (CAT) and gallic acid (GA) were developed and evaluated as active chronicwound dressings. Their physico-mechanical properties, biostability, biocompatibility and ability to inhibitin vitro myeloperoxidase (MPO) and collagenase—major enzymes related with the persistent inflammationin chronic wounds—were investigated as a function of the biopolymer composition and thepolyphenolic compound used. The results demonstrated that the molecular weight of HA influences significantlythe bulk properties of the obtained materials: higher elastic modulus, swelling ability and biostabilityagainst collagenase were measured when HA with higher molecular weights (830 and 2000 kDa)were added to the collagen matrices. The addition of CS and the polyphenols increased further the biostabilityof the sponges. Preliminary in vitro tests with fibroblasts revealed that the cells were able toadhere to all sponges. Cell viability was not affected significantly by the addition of the polyphenols;however, the presence of CS or high molecular weight HA in the sponge composition was associated withlower cellular viability. Finally, all specimens containing polyphenols efficiently inhibited the MPOactivity. The highest inhibition capacity was observed for EGCG (IC50 = 15 ± 1 lM) and it was coupledto the highest extent of binding to the biopolymers (>80%) and optimal release profile from the spongesthat allowed for prolonged (up to 3–5 days) effects.