TOPICAL ZINC-OXIDE TREATMENT INCREASES ENDOGENOUS GENE-EXPRESSION OF INSULIN-LIKE GROWTH-FACTOR-I IN GRANULATION-TISSUE FROM PORCINE WOUNDS

Application of zinc oxide has been shown to accelerate the healing of both chronic and acute wounds, but the mechanisms are unknown. We quan tified the gene expression (mRNA) for one important growth factor, ins ulin-like growth factor-1 (IGF-1) in 12 full-thickness wounds in each of three domestic pigs treated with or without topical zinc oxide. We used a RNAase protection/solution hybridisation technique to measure I GF-1 mRNA concentrations, which were 50% higher in the granulation tis sue in wounds treated with zinc oxide compared with control wounds on days 3-4 (p < 0.05), but not thereafter (up to postoperative day 11). Topical zinc oxide increased the healing rate of wounds compared to th e control group (p < 0.01). The cell composition of the granulation ti ssue was similar in the two groups. The increased gene expression of I GF-1 may be one mechanism by which topical zinc oxide enhances wound h ealing.