Zebrafish larvae as a model to demonstrate secondary iron overload.

Objectives: Thalassemia is the most common genetically inherited blood disorder arising from a defect in hemoglobin production, resulting in ineffective erythropoiesis and severe hemolytic anemia. While transfusion therapy corrects the anemia, it gives rise to secondary iron overload. Current iron chelation therapy performed using deferoxamine, and the efficiency of this drug was demonstrated here using the zebrafish animal model.

Methods: Zebrafish larvae were exposed for 3 days to iron [100 μmol L ferric ammonium citrate; 3-6 days post fertilization (dpf)]. Then, iron treated larvae were exposed to 100 μmol L deferoxamine for 3 days (6-9 dpf). Total tissue iron concentration in the whole larvae, assessed by three different assays; inductively coupled plasma mass spectrometry, colorimetry (spectrophotometry), and microscopy using iron staining followed by imaging and quantification.

Results: The three assays showed that iron treatment alone resulted in a significant increase in total iron. Deferoxamine treatment of the iron-loaded zebrafish larvae showed a significant decrease in total iron concentration.

Conclusion: This study presented a clear evidence of the effectiveness of zebrafish larvae to use as a tool to study iron overload and open the door for studying the efficiency of potential new iron chelating compounds other than commercially available ones.