title: Oxidative stress and platelet function in multiple myeloma and renal insufficiency: clinical relations of different tests.
abstract: Hemorrhagic tendency is frequent in uremic patients and is often associated with prolonged bleeding time and decreased platelet functions in vitro. Similarly, in multiple myeloma, platelet functions are affected, mainly by the inhibitory effect of paraprotein. We have studied patients with renal insufficiency and multiple myeloma to investigate the possible relation of oxidative stress to platelet functions, adhesion and aggregation activity. We observed diminished platelet aggregation response to collagen, ADP and thrombin receptor-activating peptide (TRAP) in both groups of patients as compared with normals. The adhesion of platelets to fibrin dimers was also diminished. Malondialdehyde concentration as a criterion of oxidative stress was significantly enhanced in both groups of patients together with increased concentrations of vitamins A and E. It seems to be possible that oxidative stress contributes to modification of adhesion proteins and fibrinogen and, thus, augments the observed inhibitory influence of vitamin E on platelet aggregation and adhesion. In conclusion, the concerted influence of both malondialdehyde and vitamins A and E can contribute to diminished platelet functions in renal insufficiency and augment the inhibitory influence of paraprotein on platelet functions in multiple myeloma.
authors.affiliation: First Department of Medicine, First Faculty of Medicine, Charles University, Prague, Czech Republic. cieslar@vfn.cz
authors.forename: Petr
authors.initials: P
authors.lastname: Cieslar
authors.forename: Leona
authors.initials: L
authors.lastname: Másová
authors.forename: Tomás
authors.initials: T
authors.lastname: Scheiner
authors.forename: Jitka
authors.initials: J
authors.lastname: Rysavá
authors.forename: Petra
authors.initials: P
authors.lastname: Krízová
authors.forename: Zdena
authors.initials: Z
authors.lastname: Danzigová
authors.forename: Ivan
authors.initials: I
authors.lastname: Spicka
authors.forename: Vladimír
authors.initials: V
authors.lastname: Tesar
mesh_terms: D000368:Aged; D001792:Blood Platelets / Q000502:physiology*; D005260:Female; D006470:Hemorrhage / Q000209:etiology; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood* / Q000150:complications; D018384:Oxidative Stress; D010266:Paraproteins / Q000378:metabolism; D010973:Platelet Adhesiveness; D010974:Platelet Aggregation / Q000187:drug effects; D010979:Platelet Function Tests; D051437:Renal Insufficiency / Q000097:blood* / Q000150:complications; D014801:Vitamin A / Q000097:blood; D014810:Vitamin E / Q000097:blood
chemical_list: D010266:Paraproteins; D014801:Vitamin A; D014810:Vitamin E; D008315:Malondialdehyde