Does hepcidin affect erythropoiesis in hemodialysis patients?
BACKGROUND
Prohepcidin is the precursor of hepcidin, a liver-derived peptide involved in iron metabolism by blocking its intestinal absorption and its release by the reticuloendothelial system. Iron overload and inflammation increase hepcidin expression, whereas anemia and hypoxia suppress it. In the present study prohepcidin levels were determined in the serum of hemodialysis (HD) patients and its correlations with iron metabolism markers, C-reactive protein (CRP) and hematocrit (Hct) were assessed.


METHODS
Forty-sixHD patients and 22 healthy volunteers were enrolled in the study. Hct, serum prohepcidin, CRP, iron, ferritin, transferrin saturation and transferrin receptors were measured. The weekly erythropoietin dose, last-month intravenous iron dose and the patients' demographics were recorded.


RESULTS
In comparison to the healthy volunteers, the HD patients had higher serum ferritin, transferrin receptors and CRP, lower serum iron and similar transferrin saturation and prohepcidin levels. In the patient group prohepcidin levels were negatively correlated with Hct but not with any other of the examined parameters. Multiple linear regression analysis considering age, inflammation, iron adequacy, erythropoietin dose and prohepcidin levels revealed that prohepcidin was the predominant determinant of Hct.


CONCLUSIONS
Taking into account the low Hct levels in the HD patients of our study, it seems plausible that the prohepcidin levels assessed in this group are inappropriately high. These functionally high prohepcidin levels may be associated with the factors that inhibit erythropoiesis in HD patients. On the other hand, the absence of other expected correlations indicates that further studies are needed in order to definitely clarify this aspect.
Eleftheriadis
Theodoros
T
Department of Nephrology, University of Thessaly, Larissa, Greece. elefthe@otenet.gr
Kartsios
Charalambos
C
Liakopoulos
Vassilios
V
Antoniadi
Georgia
G
Ditsa
Maria
M
Papadopoulos
Christos
C
Anifandis
Georgios
G
Skirta
Aliki
A
Markala
Dimitra
D
Stefanidis
Ioannis
I
D000368:Aged; D023181:Antimicrobial Cationic Peptides / Q000097:blood / Q000502:physiology*; D016022:Case-Control Studies; D004920:Erythropoiesis / Q000187:drug effects / Q000502:physiology*; D004921:Erythropoietin / Q000008:administration & dosage; D005260:Female; D006400:Hematocrit; D064451:Hepcidins; D006801:Humans; D007501:Iron / Q000008:administration & dosage / Q000378:metabolism; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011498:Protein Precursors / Q000097:blood / Q000502:physiology*; D006435:Renal Dialysis
D023181:Antimicrobial Cationic Peptides; D064451:Hepcidins; D011498:Protein Precursors; D004921:Erythropoietin; D007501:Iron