Background and Aims : Calciprotein particles (CPPs), generated in human blood to cope with mineral stress, represent both a physiological tool for aggregating excessive calcium and phosphate and a trigger of pathological events upon the internalisation by endothelial cells (ECs). However, unbiased proteomic profiling of CPP-treated ECs have not been performed.Methods: Primary human coronary artery (HCAEC) and internal thoracic artery ECs (HITAEC) were exposed to primary (CPP-P) or secondary (CPP-S) CPPs for 24 hours. Label-free proteomic profiling was performed by liquid chromatography-tandem mass spectrometry with ion mobility (TimsToF Pro). Bioinformatic analysis was conducted using PEAKS Studio Xpro and R software environment. Proteins identified with false discovery rate <1% and having ≥2 unique peptides were included into further analysis.View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)Conclusions: CPP-P and CPP-S promote considerable changes in the proteomic (in particular mitochondrial- and lysosomal-related) profile of ECs. Funding: This study was funded by the Ministry of Science and Higher Education of the Russian Federation (National Project Science and Universities, Research Topic No. 0419-2021-001). Background and Aims : Calciprotein particles (CPPs), generated in human blood to cope with mineral stress, represent both a physiological tool for aggregating excessive calcium and phosphate and a trigger of pathological events upon the internalisation by endothelial cells (ECs). However, unbiased proteomic profiling of CPP-treated ECs have not been performed. Methods: Primary human coronary artery (HCAEC) and internal thoracic artery ECs (HITAEC) were exposed to primary (CPP-P) or secondary (CPP-S) CPPs for 24 hours. Label-free proteomic profiling was performed by liquid chromatography-tandem mass spectrometry with ion mobility (TimsToF Pro). Bioinformatic analysis was conducted using PEAKS Studio Xpro and R software environment. Proteins identified with false discovery rate <1% and having ≥2 unique peptides were included into further analysis. Conclusions: CPP-P and CPP-S promote considerable changes in the proteomic (in particular mitochondrial- and lysosomal-related) profile of ECs. Funding: This study was funded by the Ministry of Science and Higher Education of the Russian Federation (National Project Science and Universities, Research Topic No. 0419-2021-001).

Background and Aims : Half of the bioprosthetic heart valves (BHVs) demand a repeated replacement within 15 years postimplantation because of structural valve deterioration (SVD). The pathogenesis of SVD is far from being fully understood, largely due to the lack of high-throughput investigation of failed BHVs.Methods: Failed bovine xenopericardial (XPB-BHVs, n = 5)) and porcine xenoaortic (XPA-BHVs, n = 5) BHVs and dysfunctional AVs (n = 5) were excised during the heart valve replacement. Label-free proteomic profiling was performed by means of liquid chromatography-tandem mass spectrometry with ion mobility (TimsToF Pro). Bioinformatic analysis was conducted using PEAKS Studio Xpro and R software environment. Proteins identified with false discovery rate < 1% and having ≥ 2 unique peptides were included into further analysis.View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)Conclusions: In contrast to dysfunctional native AVs, failing BHVs suffer from complement-driven neutrophil invasion, excessive proteolysis, and unwanted coagulation. Funding: This research was funded by the Russian Science Foundation, grant number 21-75-10107. Background and Aims : Half of the bioprosthetic heart valves (BHVs) demand a repeated replacement within 15 years postimplantation because of structural valve deterioration (SVD). The pathogenesis of SVD is far from being fully understood, largely due to the lack of high-throughput investigation of failed BHVs. Methods: Failed bovine xenopericardial (XPB-BHVs, n = 5)) and porcine xenoaortic (XPA-BHVs, n = 5) BHVs and dysfunctional AVs (n = 5) were excised during the heart valve replacement. Label-free proteomic profiling was performed by means of liquid chromatography-tandem mass spectrometry with ion mobility (TimsToF Pro). Bioinformatic analysis was conducted using PEAKS Studio Xpro and R software environment. Proteins identified with false discovery rate < 1% and having ≥ 2 unique peptides were included into further analysis. Conclusions: In contrast to dysfunctional native AVs, failing BHVs suffer from complement-driven neutrophil invasion, excessive proteolysis, and unwanted coagulation. Funding: This research was funded by the Russian Science Foundation, grant number 21-75-10107.

Fracture healing is a complex process in which the periosteum and endosteum become the main sources of osteoblast progenitor cells. However, cellular mechanisms and signaling cascades underlying the early stages of osteoblast progenitors differentiation in adult bone are still not well understood. Therefore, we performed shotgun proteomics analysis of primary culture of isolated human osteoblasts from femur of adult donors in undifferentiated conditions and on the fifth day of osteogenic differentiation in vitro. This is an early timepoint in which we have observed no extracellular matrix mineralization yet. 1612 proteins identified with at least two unique peptides were included in proteomics analysis. Data are available via ProteomeXchange with identifier PXD033697. Despite the fact, that matrix mineralization starts only after induction of osteogenic differentiation, we revealed unexpectedly weak physiological shift associated with a decrease of cells proliferative activity and changes in proteins involved in extracellular matrix secretion and organization. We demonstrated that osteoblasts were positive for markers of later osteogenic differentiation stages during standard cultivation: osteopontin, osteocalcin, BMP-2/4 and RUNX2. Therefore, further differentiation required for matrix mineralization needs minimal physiological changes.