Transforming growth factor 15 increased in severe aplastic anemia patients

Objectives: The patients with severe aplastic anemia (SAA) usually rely on red cell transfusion which lead to secondary iron overload. Transforming growth differentiation factor-15 (GDF-15) plays an important role in erythropoiesis and iron regulation. In this study, we investigated the level of GDF-15 and other indexes of iron metabolism in SAA patients to explore the correlation with GDF-15 and iron overload in SAA. Methods: The levels of serum GDF-15, hepcidin (Hepc), and erythropoietin (EPO) were determined by ELISA. The levels of serum iron (SI), ferritin, TIBC, and transferrin saturation (TS) were measured by an auto analyzer. Iron staining of bone marrow cells was used for testing extracellular and intracellular iron. Results: The GDF-15 level in the experimental group was higher than that of the case-control group and normal control group (all p<0.05). The Hepc level in the experimental group and case-control group were both higher than that of healthy controls (all p<0.05). The Hepc level was significantly lower in the experimental group patients who had excessive GDF-15 (r=-0.766, p=0.000). There was a positive correlation between the level of GDF15 and EPO in the experimental group (r=0.68, p<0.000). The level of GDF15 in SAA patients was positively correlated with SI levels (r=0.537, p=0.008), TS levels (r=0.466, p=0.025), and sideroblasts (%) (r=0.463, p=0.026). Moreover, there was a positive correlation between GDF-15 level and blood transfusion-dependent time (r=0.739, p=0.000). Discussion: Our data indicated that GDF-15 plays an important role in iron metabolism in SAA. GDF-15 might be a novel target for SAA therapy.