ABSTRACT
Objective To explore the effect of bacterial endotoxin lipopolysaccharide (LPS) on wound healing by observation of change in expression of matrix metalloproteinases (MMPs) and specific tissue inhibitors of metalloproteinases (TIMPs) in fibroblasts after the challenge of lipopolysaccharide. Methods Human dermal fibroblasts were cultured in RPMI medium containing 10% fetal calf serum (FCS). At cellular confluence the medium was changed, and the cells were cultured under serum free conditions with 0.1% bovine serum albumin (BSA) in the presence of LPS (0, 10?g/ml, 100?g/ml and 1000?g/ml). All cultures were maintained at 37℃ in a humidified atmosphere of 5% CO_2 in air. After 48-hour treatment, the medium was collected for measurement of MMPs by fluorescence labeled gelatin zymography and for measurement of TIMPs by fluorescence labeled reverse gelatin zymography. The expressions of MMPs and TIMPs were quantitatively analyzed with the band's area and density from the gel image using the Phoretix software. Results LPS up-regulated the expression of both MMPs and TIMPs in fibroblasts, and expression of TIMPs was higher than that of MMPs. Compared with base level, MMPs respectively increased 1.3, 1.7 and 1.6 times, TIMP-1 respectively increased 3, 4.5 and 3.6 times, TIMP-2 respectively increased 3, 6 and 5.6 times. Conclusion It seems that LPS showed no damaging effect on fibroblasts in regulation of matrix accumulation in wound healing.