Alteration of extracellular matrix modulators after nonablative laser therapy in skin rejuvenation

Nonablative laser therapy is widely practised for skin rejuvenation, which stimulates collagen production and dermal matrix remodelling. Matrix remodelling is primarily modulated by a coordinated action of matrix metalloproteinases (MMPs) and their inhibitors, but the effects of nonablative lasers on these matrix modulators are not fully investigated.

To evaluate the changes in matrix modulators, such as MMP-1, MMP-2, MMP-3, MMP-9 and MT1-MMP, and their inhibitors (TIMP-1, TIMP-2 and RECK in particular), after nonablative laser treatments of human facial skin.

Twenty-four adult volunteers received a series of four nonablative laser treatments separated by 3-week intervals on facial skin. Two-millimetre skin punch biopsies were obtained at baseline and 3 weeks after the last treatment.

Nonablative laser treatments led to a robust increase in two major dermal matrix components, type I collagen and tropoelastin. Among MMPs tested, levels of MMP-2 mRNA were statistically significantly increased, but the amount of active MMP-2 was rather reduced. More importantly, the expression level of RECK was significantly enhanced by laser treatments.

Clinical outcomes following nonablative laser treatments may result not only from increased biosynthesis but also from decreased degradation, via an induction of RECK expression, of matrix proteins.