Induction of matrix metalloproteinase-1 in in vitro experimental model using a novel three-dimensional culture system

The aim of this study was to determine whether experimentally punched wound s may influence the connective tissue metabolism of human fibroblast in a t hree dimensional culture supplemented with L-ascorbic acid. This culture wa s designed for human dermal fibroblasts to organize a three-dimensional der mis-like structure by accumulating self-produced extracellular matrixes. In order to examine the effects of the wound, mRNA expression and production of type I collagen, matrix metalloproteinase-1 (MMP-1) and tissue inhibitor s of metalloproteinase-1 (TIMP-1) were sequentially examined up to 72 hrs a fter the wound was created, The levels of mRNA expression of MMP-1 were hig her at 12 and 24 hrs compared with the initial level and then gradually dec reased in studies both with and without wounds. However, the levels of mRNA expression of MMP-1 between 6 to 48 hrs were higher in wounds than in non- wounds. The production of proMMP-1 was also significantly enhanced. There w ere no significant differences in the levels of mRNA expression or the prod uction of type I collagen and TIMP-1 with the presence or absence of a woun d. These results indicate that MMP-1 is synthesized to initiate the tissue restoration in response to the disruption of the three dimensional structur e. Thus, this culture system provides a new experimental tool with which to examine the direct effect of mechanical changes on connective tissue metab olism in human dermal fibroblasts.