Fibrinogen is one of the plasma proteins most susceptible to oxidative modification. It has been suggested that modification of fibrinogen may cause thrombotic/bleeding complications associated with many pathophysiological states of organism. We exposed fibrinogen molecules to three different modification reagents-malondialdehyde, sodium hypochlorite, and peroxynitrite-that are presented to various degrees in different stages of oxidative stress. We studied the changes in fibrin network formation and platelet interactions with modified fibrinogens under flow conditions. The fastest modification of fibrinogen was caused by hypochlorite. Fibers from fibrinogen modified with either reagent were thinner in comparison with control fibers. We found that platelet dynamic adhesion was significantly lower on fibrinogen modified with malondialdehyde and significantly higher on fibrinogen modified either with hypochlorite or peroxynitrite reflecting different prothrombotic/antithrombotic properties of oxidatively modified fibrinogens. It seems that, in the complex reactions ongoing in living organisms at conditions of oxidation stress, hypochlorite modifies proteins (e.g., fibrinogen) faster and more preferentially than malondialdehyde. It suggests that the prothrombotic effects of prior fibrinogen modifications may outweigh the antithrombotic effect of malondialdehyde-modified fibrinogen in real living systems.

• MeSH
• Platelet Adhesiveness drug effects   physiology   MeSH
• Sodium Hypochlorite pharmacology   MeSH
• Fibrinogen chemistry   metabolism   pharmacology   MeSH
• Indicators and Reagents chemistry   pharmacology   MeSH
• Cells, Cultured MeSH
• Peroxynitrous Acid chemistry   MeSH
• Humans MeSH
• Malondialdehyde chemistry   pharmacology   MeSH
• Oxidative Stress drug effects   physiology   MeSH
• Blood Platelets drug effects   metabolism   MeSH
• Structure-Activity Relationship MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Sodium Hypochlorite MeSH
• Fibrinogen MeSH
• Indicators and Reagents MeSH
• Peroxynitrous Acid MeSH
• Malondialdehyde MeSH

BACKGROUND: Refractory anemia and refractory anemia with ringed sideroblasts are two myelodysplastic syndrome (MDS) subgroups linked with anemia. MDS is a group of heterogeneous oncohematological bone marrow disorders characterized by ineffective hematopoiesis, blood cytopenias, and progression of the disease toward acute myeloid leukemia. The aim of this study was to search for plasma proteome changes in MDS patients with refractory anemia and refractory anemia with ringed sideroblasts. RESULTS: A total of 26 patient and healthy donor plasma samples were depleted of fourteen high-abundant plasma proteins, separated with 2D electrophoresis, and statistically processed with Progenesis SameSpots software. 55 significantly differing spots were observed and corresponded to 39 different proteins identified by nanoLC-MS/MS. Changes in the fragments of the inter-alpha-trypsin inhibitor heavy chain H4 protein were observed. Using mass spectrometry-based relative label-free quantification of tryptic peptides, there were differences in alpha-2-HS-glycoprotein peptides, while no differences were observed between the control and patient sample groups for retinol-binding protein 4 peptides. CONCLUSIONS: This study describes plasma proteome changes associated with MDS patients with refractory anemia and refractory anemia with ringed sideroblasts. Changes observed in the inter-alpha-trypsin inhibitor heavy chain H4 fragments were in agreement with our previous studies of other MDS subgroups: refractory cytopenia with multilineage dysplasia and refractory anemia with excess blasts subtype 1. Mass spectrometry-based relative quantification of retinol-binding protein 4 peptides has shown that there are differences in the modification of this protein between refractory anemia with excess blasts subtype 1 patients and MDS patients with refractory anemia and refractory anemia with ringed sideroblasts. Alpha-2-HS-glycoprotein seems to be a new potential MDS biomarker candidate.

• Publication type
• Journal Article MeSH

BACKGROUND: Refractory anemia with excess blasts subtype 1 (RAEB-1) is a subgroup of myelodysplastic syndrome. It represents a heterogeneous group of oncohematological bone marrow diseases, which occur particularly in elderly patients. The aim of this proteomic study was to search for plasma protein alterations in RAEB-1 patients. RESULTS: A total of 24 plasma samples were depleted of fourteen high-abundant plasma proteins, analyzed with 2D SDS-PAGE, compared, and statistically processed with Progenesis SameSpots software. Proteins were identified by nanoLC-MS/MS. Retinol-binding protein 4 and leucine-rich alpha-2-glycoprotein were relatively quantified using mass spectrometry. 56 significantly differing spots were found; and in 52 spots 50 different proteins were successfully identified. Several plasma proteins that changed either in their level or modification have been described herein. The plasma level of retinol-binding protein 4 was decreased, while leucine-rich alpha-2-glycoprotein was modified in RAEB-1 patients. Changes in the inter-alpha-trypsin inhibitor heavy chain H4, altered protein fragmentation, or fragments modifications were observed. CONCLUSIONS: This study describes proteins, which change quantitatively or qualitatively in the plasma of RAEB-1 patients. It is the first report on qualitative changes in the leucine-rich alpha-2-glycoprotein in the RAEB-1 subgroup of myelodysplastic syndrome. Described changes in the composition or modification of inter-alpha-trypsin inhibitor heavy chain H4 fragments in RAEB-1 are in agreement with those changes observed in previous study of refractory cytopenia with multilineage dysplasia, and thus H4 fragments could be a marker specific for myelodysplastic syndrome.

• Publication type
• Journal Article MeSH

BACKGROUND: Refractory cytopenia with multilineage dysplasia (RCMD) is a subgroup of myelodysplastic syndrome (MDS), which belongs to oncohematological diseases, occurring particularly in elderly patients, and represents a heterogeneous group of bone marrow diseases. The goal of this study was to look for plasma proteins that changed quantitatively or qualitatively in RCMD patients. RESULTS: A total of 46 plasma samples were depleted, proteins were separated by 2D SDS-PAGE (pI 4-7), and proteomes were compared using Progenesis SameSpots statistical software. Proteins were identified by nanoLC-MS/MS. Sixty-one unique, significantly (p < 0.05, ANOVA) different spots were found; proteins in 59 spots were successfully identified and corresponded to 57 different proteins. Protein fragmentation was observed in several proteins: complement C4-A, complement C4-B, inter-alpha-trypsin inhibitor heavy chain H4, and endorepellin. CONCLUSIONS: This study describes proteins, which change quantitatively or qualitatively in RCMD patients, and represents the first report on significant alterations in C4-A and C4-B complement proteins and ITIH4 fragments in patients with MDS-RCMD.

• Publication type
• Journal Article MeSH