Changes in extracellular matrix glycosaminoglycans during the wound repair allowed us to apply the burn model in which therapeutic efficacy of propolis and silver sulfadiazine was compared. Burns were inflicted on four pigs. Glycosaminoglycans isolated from healthy and burned skin were quantified using a hexuronic acid assay, electrophoretic fractionation, and densitometric analyses. Using the reverse-phase HPLC the profile of sulfated disaccharides released by chondroitinase ABC from chondroitin/dermatan sulfates was estimated. Chondroitin/dermatan sulfates and hyaluronic acid were found in all samples. Propolis stimulated significant changes in the content of particular glycosaminoglycan types during burn healing. Glycosaminoglycans alterations after silver sulfadiazine application were less expressed. Propolis maintained high contribution of 4-O-sulfated disaccharides to chondroitin/dermatan sulfates structure and low level of 6-O-sulfated ones throughout the observed period of healing. Propolis led to preservation of significant contribution of disulfated disaccharides especially 2,4-O-disulfated ones to chondroitin sulfates/dermatan sulfates structure throughout the observed period of healing. Our findings demonstrate that propolis accelerates the burned tissue repair by stimulation of the wound bed glycosaminoglycan accumulation needed for granulation, tissue growth, and wound closure. Moreover, propolis accelerates chondroitin/dermatan sulfates structure modification responsible for binding growth factors playing the crucial role in the tissue repair.

Background: The mechanisms which cause age-dependent remodeling of connective tissue are still not fully understood. Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) constitute an important proteolytic pathway affecting physiological matrix remodeling. Objective: The way in which changes in the extracellular matrix metabolism during the ageing process influence the level of circulating MMP-3 and MMP-10, as well as their tissue inhibitors TIMP-1 and TIMP-2, in a healthy population was investigated in this study. Methods: Blood samples were taken from 81 healthy individuals aged 6–62 years and measured for MMP-3, MMP-10, TIMP-1 and TIMP-2 levels using enzyme-linked immunosorbent assays. Polyacrylamide gel electrophoresis followed by Western immunoblotting allowed for the detection of pro- and active forms of both MMPs. Results: Serum MMP-3 and TIMP-1 values were positively correlated with age (r = 0.44, p = 0.00001 and r = 0.28, p = 0.012, respectively). A contrary tendency was found for MMP-10 and TIMP-2 serum levels. A strong age-related decrease in MMP-10 (–0.53; p = 0.000) and TIMP-2 (–0.52; p = 0.000) was noticed in our study. Gender was a significant factor modifying MMP/TIMP potential, except for the MMP-10 level. Conclusions: The data presented indicate that changes in MMP/TIMP balance occur in physiological ageing. Moreover, these findings highlight the necessity of utilizing age- and sex-matched values for analysis of MMPs and TIMPs in the pathological conditions.

This study was aimed at assessing the dynamics of vitronectin (VN), laminin (LN), and heparan sulfate/heparin (HS/HP) content changes during experimental burn healing. VN, LN, and HS/HP were isolated and purified from normal and injured skin of domestic pigs, on the 3rd, 5th, 10th, 15th, and 21st days following thermal damage. The wounds were treated with apitherapeutic agent (propolis), silver sulfadiazine (SSD), physiological salt solution, and propolis vehicle. VN and LN were quantified using an immunoenzymatic assay and HS/HP was estimated by densitometric analysis. Propolis treatment stimulated significant increases in VN, LN, and HS/HP contents during the initial phase of study, followed by a reduction in the estimated extracellular matrix molecules. Similar patterns, although less extreme, were observed after treatment with SSD. The beneficial effects of propolis on experimental wounds make it a potential apitherapeutic agent in topical burn management.