We have previously shown that oxidative stress is generated in pathological red blood cells (RBC) in congenital (thalassemia, sickle cell anemia) and acquired (myelodysplastic syndrome and paroxysmal nocturnal hemoglobinuria) hemolytic anemias. In the present study we tested whether a similar mechanism occurs in hereditary spherocytosis (HS) which is a heterogeneous group of disorders, where RBC have short survival due to primary deficiency in spectrin, ankyrin-1, band 3 or protein 4.2 in their membranes. Secondary protein deficiencies resulting from oxidative stress are often observed and may be involved in the outcome of the disease. Seventeen patients from 7 families with clinical and laboratory diagnosis of mild to severe HS were examined. All patients were anemic, (Hb ranging from 5.3 to 10.5 g/dl) and 7 were splenectomized. Twelve patients received 5 to 58 units of blood. The diagnosis was based on spherocyte morphology, increased MCHC (33–38 g/dl), decreased MCV (<80 fl in 11 patients) and increased osmotic fragility (>75%) in all of them. Using flow cytometry techniques, we showed that RBC from HS patients generate high amounts (1.65-fold) reactive oxygen species (ROS), as well as membrane lipid peroxides (LP) (3.04-fold), and lower levels (2.05-fold) of the cellular anti-oxidant reduced glutathione (GSH) compared with RBC obtained from normal donors of matched gender and age (Figure). In order to determine whether oxidative stress plays a role in hemolysis in HS, we incubated HS-RBC with their autologous plasma and added antioxidants such as N-acetylcystein, vitamin C and the vitamin E derivative, tocotrinol, each at 1 mM, for 12 hours. The results showed that the antioxidants protected HS-RBC from lysis. Our results provide a direct evidence for oxidative stress in RBC from HS patients similar to findings in other hemolytic anemias which contribute to the magnitude of their lysis, and suggest that treatment with antioxidants may attenuate some of the clinical symptoms of these patients.

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Topics:
hemolysis, hereditary spherocytosis, oxidative stress, antioxidants, anemia, hemolytic anemia, acetylcysteine, ankyrins, ascorbic acid, cisplatin/methotrexate/vinblastine protocol

Author notes

Disclosure: No relevant conflicts of interest to declare.

2007, The American Society of Hematology
2007
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