Plasma substance P and soluble P-selectin as biomarkers of β-thalassemia induced hypercoagulability

Background: Hypercoagulability in thalassemia especially in thalassemia major has emerged as a complication of the disease. There is evidence of increased platelet aggregation and increased proportion of platelets expressing P-selectin in thalassemia. P-selectin is a cell adhesion molecule which plays a key role in hemostasis and thrombosis, mediating platelet rolling and generating procoagulant molecules. Substance P is one of the tachykinins which constitute a family of neuropeptides. It now appears that platelets contain substance P which is released upon stimulation leading to faster and more extensive aggregation. Objective: To detect the possible role of substance P and soluble P-selectin (sP-selectin) as biomarkers of hypercoagulability in patients with beta-thalassemia major. Subjects and methods: Venous blood samples were collected from ten normal control subjects and thirty patients with beta-thalassemia major (divided into two groups, splenectomized and unsplenectomized). To all studied individuals, plasma substance P and sP-selectin were assayed by an enzyme linked Immunosorbent assay (ELISA). Results: Higher levels of plasma substance P and sP-selectin were observed in thalassemic patients versus the controls. Both substance P and sP-selectin were significantly higher in the splenectomized group of patients. Conclusions: Substance P and sP-selectin might have a role in platelet activation and subsequent hypercoagulability in thalassemic patients.