THE EFFECT OF VARIOUS COMPOSITE COATINGS OF TITANIUM MATRIX ON OSTEOGENIC DIFFERENTIATION OF INTERSTITIAL CELLS OF THE HUMAN AORTIC VALVE

Highlights The study involves experiments with titanium substrates with various composite coatings. The aim of the study was to assess different methods of diagnostics of artificial implant materials and evaluate the effect of coatings on osteogenic differentiation in interstitial cells of the human aortic valve. Background . Currently, the only medical treatment for aortic stenosis is aortic valve replacement. At the same time, calcific aortic stenosis is the third most prevalent cardiovascular disease that affects up to 10% of the population by the age of 80. In this regard, it is important to develop materials for aortic valve prostheses that would be highly biocompatible, chemically stable, non-thrombogenic, non-immunogenic and non-osteogenic. Aim . To assess the impact of composite coatings of titanium bases on osteogenic differentiation of valve`s interstitial cells and to analyze the methods of express diagnostics of artificial implant materials. Methods . The study examined titanium samples with three different coatings. The interstitial cells of the aortic valve were cultured on the studied materials. Using the PCR-RT method, the level of changes in the expression of osteogenic markers RUNX2, COL1a1, ALP under the influence of osteogenic stimuli was analyzed. To determine the level of calcification in cells, we stained the samples with alizarin red and conducted spectrophotometric analysis. Several RNA isolation methods were evaluated. Results . The most optimal RNA isolation method involves the use of a poly(A) tails. Moreover, we developed a protocol for the absorption of calcium from composite materials. We noted multidirectional changes in the expression of RUNX2, ALP, and COL1A1 genes in cells cultured on coated titanium samples compared to controls. The intensity of expression differed depending on the type of coatings; these data correlated with the intensity of staining with alizarin. Thus, different types of coatings affect the processes of osteogenic differentiation in cells in different ways. Conclusion . The duration of express diagnostics was 21 days and included the study of gene expression of osteodifferentiation markers at a time point of 96 hours and staining with alizarin red on day 21 from the start of osteodifferentiation. It has been established that polymer coatings affect osteogenic differentiation, however, all the studied coatings cannot be recommended for valve prostheses, it is advisable to use them to enhance osteogenic processes.