The role of matrix metalloproteinases and their tissue inhibitors in the formation of hypertrophic skin scars with the use of a pulsed dye laser and Fermencol phonophoresis

BACKGROUND: An imbalance between matrix metalloproteinases (MMPs) expression and tissue inhibitors of MMP is considered as a possible mechanism for impaired collagen synthesis and degradation, which leads to the development of hypertrophic scars. The use of a vascular laser, in particular a pulsed dye laser, leads to coagulation of the vascular locus that feeds the hypertrophic skin scar, resulting in a decrease in extracellular matrix synthesis. The use of collagenase phonophoresis increases the effectiveness of laser therapy due to the destruction of the extracellular matrix.

AIM: To study the role of matrix metalloproteinases and their tissue inhibitors in the pathogenesis of immature hypertrophic skin scars and to evaluate the dynamics of enzymes during the combined use of a pulsed dye laser and Fermenkol phonophoresis.

MATERIAL AND METHODS: The study was performed with the participation of 125 patients aged 22 to 55 years with immature (up to 6 months) hypertrophic skin scars. All patients were divided into 4 groups according to the simple fixed randomization procedure. The first group (control, n=32) received course local compression therapy using silicone plates for 2 months. The second group (main group I, n=31) underwent two courses of Fermencol phonophoresis (5 daily procedures lasting 10 minutes each with a break of 3–4 weeks). The third group (main group II, n=31) underwent two pulsed dye laser procedures with an interval of 4 weeks. The fourth group (main III, n=31) received complex treatment, which included a combination of two pulsed dye laser procedures and two cycles of Fermenkol phonophoresis. The study of the clinical condition of patients was carried out according to the modified Vancouver scar scale (VSS). The content of MMP and tissue inhibitor of metalloproteinase-1 in blood serum was determined by enzyme immunoassay. Patients were examined twice: before the start and 2 weeks after the end of the course of treatment. To form a sample of reference values of MMPs and tissue inhibitors of metalloproteinases (TIMPs), a group of 20 somatically healthy individuals was used.

RESULTS: Initially reduced levels of MMP-1 and MMP-9 were found in the blood serum of patients with immature hypertrophic skin scars, with high values of TIMP-1, which allows us to consider reduced expression as an important link in the pathogenesis of the fibroproliferative process in the skin, which causes excessive deposition of extracellular matrix components. The use of pulsed dye laser in combination with Fermencol phonophoresis was accompanied by an increase in the content of MMP in the blood serum of patients with immature hypertrophic skin scars, which positively correlated with the severity of the clinical result of treatment, assessed by VSS.

CONCLUSION: A conclusion was made about the clinical and pathogenetic significance of MMPs and TIMPs in the development of fibroplastic processes, which allows us to consider these biochemical parameters as informative criteria for the effectiveness of the therapy.