Biol Trace Elem Res DOI 10.1007/s12011-015-0441-1
Mineral Levels in Thalassaemia Major Patients Using Different Iron Chelators Gizem Esra Genc 1 & Zeynep Ozturk 1 & Saadet Gumuslu 1 & Alphan Kupesiz 1
Received: 15 May 2015 / Accepted: 7 July 2015 # Springer Science+Business Media New York 2015
Abstract The goal of the present study was to determine the levels of minerals in chronically transfused thalassaemic patients living in Antalya, Turkey and to determine mineral levels in groups using different iron chelators. Three iron chelators deferoxamine, deferiprone and deferasirox have been used to remove iron from patients’ tissues. There were contradictory results in the literature about minerals including selenium, zinc, copper, and magnesium in thalassaemia major patients. Blood samples from the 60 thalassaemia major patients (the deferoxamine group, n = 19; the deferiprone group, n = 20 and the deferasirox group, n = 21) and the controls (n = 20) were collected. Levels of selenium, zinc, copper, magnesium, and iron were measured, and all of them except iron showed no significant difference between the controls and the patients regardless of chelator type. Serum copper levels in the deferasirox group were lower than those in the control and deferoxamine groups, and serum magnesium levels in the deferasirox group were higher than those in the control, deferoxamine and deferiprone groups. Iron levels in the patient groups were higher than those in the control group, and iron levels showed a significant correlation with selenium and magnesium levels. Different values of minerals in thalassaemia major patients may be the result of different dietary intake, chelator type, or regional differences in where patients live. That is why minerals may be measured in thalassaemia major patients at intervals, and deficient minerals should be replaced. Being careful about levels of copper and magnesium in thalassaemia major patients using deferasirox seems to be beneficial. * Saadet Gumuslu [email protected] 1
Faculty of Medicine, Akdeniz University, Antalya, Turkey
Keywords Thalassaemia . Iron chelator . Selenium . Zinc . Copper . Magnesium . Iron
Introduction Thalassaemia major (TM) is an inherited and chronic form of haemolytic anaemia, characterized by haemoglobin production abnormalities. Thalassaemia major is caused by decreased or impaired biosynthesis of the beta globin chains of haemoglobin [1]. The main treatment of this disease is blood transfusion. Regular blood transfusions lead to iron overload in patients’ tissues. In these patients, the most common cause of death is heart failure due to transfusional iron overload [2]. Since chelation therapies have improved, TM patients have started to live longer. Therefore, several iron chelators have been used to reduce this transfusional iron overload in TM patients. There are currently three approved commercially available iron chelators—deferoxamine (Desferal, DFO), deferiprone (Ferriprox, L1, DFP) and deferasirox (ICL670, Exjade, DFX)—to remove iron from patients’ tissues. The first iron chelator approved for clinical use was deferoxamine. The DFO application was subcutaneous while DFX and DFP were orally administered [3, 4]. Minerals such as selenium, zinc, copper, magnesium, and iron are essential in many biological processes, and they have critical roles in enzymes as cofactors in metalloenzymes, such as glutathione peroxidase, or a nonenzymatic protein, such as ferritin [5]. Selenium (Se) is an essential trace element and a functional component of the antioxidant defence system, an essential constituent of the thioredoxin reductase (TrxR) and glutathione peroxidase (GPx), and also many important proteins are included selenium [6]. Zinc (Zn) is a structural element of many proteins. It is known that zinc is essential for growth hormone and insulin-like growth factor in the body [7]. Copper (Cu) is an essential mineral for cellular physiology
with many key roles in antioxidant activity. Structural and redox-based actions of copper in proteins and enzymatic processes make us think copper should be considered as a third key modulator after calcium and zinc [8]. Magnesium (Mg) plays an essential role in the activity of many enzymes involved in cellular metabolism. Magnesium deficiency leads to the development of haemolytic anaemia characterized by changes in erythrocyte morphology [9]. A previous study showed that antioxidant treatment with Mg could reduce oxidative damage to the RBC membrane and improve anion transport efficiency [10]. Iron plays vital roles in oxygen transport, short-term oxygen storage and energy generation [11]. On the other hand, iron leads to production of reactive oxygen species via the Fenton reaction; thus, iron overload damages the redox balance of the cells [12]. There were contradictory results in the literature about minerals in TM patients. Although some studies have shown that serum of patients receiving an iron chelator was not deficient in trace elements, others have shown that TM patients had low levels of minerals compared to healthy subjects [13–16]. In this study, we aimed to determine the levels of minerals in chronically transfused thalassaemic patients living in Antalya, Turkey and to determine mineral levels in groups using different iron chelators.
Methods Design This study was approved by the Akdeniz University Clinical Research Ethics Committee of the Faculty of Medicine. Informed consent was taken from the healthy subjects in the control group and the thalassaemia major patients before their blood samples were collected. Signed parental permission was taken for subjects under the age of 18 year. Blood samples were taken from the patients and control subjects. Levels of selenium, zinc, copper, magnesium, and iron were measured. Control Group The control group (n = 20) was selected from healthy volunteers living in the Antalya region. A whole blood examination and haemoglobin electrophoresis were performed to exclude thalassaemia traits or any haemolytic anaemia for the controls. Patient Groups The thalassaemia major patients included in this study followed up with the Department of Paediatric Haematology, Akdeniz University Hospital, Antalya, Turkey. All the patients received regular blood transfusion and used iron chelation therapy as a monotherapy over 2 years. We also divided patients into three groups according to chelators therapy ((the
deferoxamine (Desferal, DFO) group, n = 19, aged 11– 32 years), (the deferiprone (Ferriprox, DFP) group, n = 20, aged 10–36 years) and (the deferasirox (Exjade, DFX) group, n = 21, aged 12–37 years)). The mean of the daily doses of DFO, DFP and DFX were 47.84 mg/kg/day, 76.32 mg/kg/day and 29.9 mg/kg/day, respectively. No patient received combined chelation therapy. Sample Collection Blood samples from the patients were collected just before the next transfusion. Blood samples of the patients and the controls for zinc, copper, magnesium, iron and ferritin were collected in serum tubes and sent to the clinical laboratory. Whole blood samples for selenium determination were collected in heparin tubes, centrifuged at 3000×g for 10 min at 4 °C, and separated plasma samples were stored at −80 °C until analysis. Measurement of Minerals Selenium levels were analysed by an ICP Mass Spectrometry (ICP-MS) (Parkin Elmer) (United States) system. Zinc levels were measured with a Shimadzu AA-7000 Atomic Absorption Spectrophotometer (Japan) system. Copper levels were measured by commercial kit according to the manufacturer’s instructions (FAR Diagnostic, Verona, Italy). Levels of magnesium and iron were measured with a Roche/Hitachi cobas 8000 (Switzerland) system. Ferritin levels were determined by electrochemiluminescence immunoassay method with a Roche/Hitachi cobas 8000 system. Statistical Analysis Statistical analysis was performed using SPSS software (Version 18.0, New York, USA). For data of normal distribution, one-way analysis of variance (ANOVA) procedures were used for comparisons among the different groups. To determine virtual difference in iron, copper and magnesium among the groups, we used Fisher’s least significant difference (LSD) for the significant result, and we also used Dunnett’s test in comparison with the controls. Group differences in haemoglobin, ferritin and zinc were tested using KruskalWallis test with post hoc Bonferroni test. Pairwise comparisons of the patient and control groups were performed using Mann–Whitney U test for nonparametric and ındependent T test for parametric data. Spearman’s rho correlation coefficient was calculated to test the relationship between variables. P values
Mineral Levels in Thalassaemia Major Patients Using Different Iron Chelators Gizem Esra Genc 1 & Zeynep Ozturk 1 & Saadet Gumuslu 1 & Alphan Kupesiz 1
Received: 15 May 2015 / Accepted: 7 July 2015 # Springer Science+Business Media New York 2015
Abstract The goal of the present study was to determine the levels of minerals in chronically transfused thalassaemic patients living in Antalya, Turkey and to determine mineral levels in groups using different iron chelators. Three iron chelators deferoxamine, deferiprone and deferasirox have been used to remove iron from patients’ tissues. There were contradictory results in the literature about minerals including selenium, zinc, copper, and magnesium in thalassaemia major patients. Blood samples from the 60 thalassaemia major patients (the deferoxamine group, n = 19; the deferiprone group, n = 20 and the deferasirox group, n = 21) and the controls (n = 20) were collected. Levels of selenium, zinc, copper, magnesium, and iron were measured, and all of them except iron showed no significant difference between the controls and the patients regardless of chelator type. Serum copper levels in the deferasirox group were lower than those in the control and deferoxamine groups, and serum magnesium levels in the deferasirox group were higher than those in the control, deferoxamine and deferiprone groups. Iron levels in the patient groups were higher than those in the control group, and iron levels showed a significant correlation with selenium and magnesium levels. Different values of minerals in thalassaemia major patients may be the result of different dietary intake, chelator type, or regional differences in where patients live. That is why minerals may be measured in thalassaemia major patients at intervals, and deficient minerals should be replaced. Being careful about levels of copper and magnesium in thalassaemia major patients using deferasirox seems to be beneficial. * Saadet Gumuslu [email protected] 1
Faculty of Medicine, Akdeniz University, Antalya, Turkey
Keywords Thalassaemia . Iron chelator . Selenium . Zinc . Copper . Magnesium . Iron
Introduction Thalassaemia major (TM) is an inherited and chronic form of haemolytic anaemia, characterized by haemoglobin production abnormalities. Thalassaemia major is caused by decreased or impaired biosynthesis of the beta globin chains of haemoglobin [1]. The main treatment of this disease is blood transfusion. Regular blood transfusions lead to iron overload in patients’ tissues. In these patients, the most common cause of death is heart failure due to transfusional iron overload [2]. Since chelation therapies have improved, TM patients have started to live longer. Therefore, several iron chelators have been used to reduce this transfusional iron overload in TM patients. There are currently three approved commercially available iron chelators—deferoxamine (Desferal, DFO), deferiprone (Ferriprox, L1, DFP) and deferasirox (ICL670, Exjade, DFX)—to remove iron from patients’ tissues. The first iron chelator approved for clinical use was deferoxamine. The DFO application was subcutaneous while DFX and DFP were orally administered [3, 4]. Minerals such as selenium, zinc, copper, magnesium, and iron are essential in many biological processes, and they have critical roles in enzymes as cofactors in metalloenzymes, such as glutathione peroxidase, or a nonenzymatic protein, such as ferritin [5]. Selenium (Se) is an essential trace element and a functional component of the antioxidant defence system, an essential constituent of the thioredoxin reductase (TrxR) and glutathione peroxidase (GPx), and also many important proteins are included selenium [6]. Zinc (Zn) is a structural element of many proteins. It is known that zinc is essential for growth hormone and insulin-like growth factor in the body [7]. Copper (Cu) is an essential mineral for cellular physiology
with many key roles in antioxidant activity. Structural and redox-based actions of copper in proteins and enzymatic processes make us think copper should be considered as a third key modulator after calcium and zinc [8]. Magnesium (Mg) plays an essential role in the activity of many enzymes involved in cellular metabolism. Magnesium deficiency leads to the development of haemolytic anaemia characterized by changes in erythrocyte morphology [9]. A previous study showed that antioxidant treatment with Mg could reduce oxidative damage to the RBC membrane and improve anion transport efficiency [10]. Iron plays vital roles in oxygen transport, short-term oxygen storage and energy generation [11]. On the other hand, iron leads to production of reactive oxygen species via the Fenton reaction; thus, iron overload damages the redox balance of the cells [12]. There were contradictory results in the literature about minerals in TM patients. Although some studies have shown that serum of patients receiving an iron chelator was not deficient in trace elements, others have shown that TM patients had low levels of minerals compared to healthy subjects [13–16]. In this study, we aimed to determine the levels of minerals in chronically transfused thalassaemic patients living in Antalya, Turkey and to determine mineral levels in groups using different iron chelators.
Methods Design This study was approved by the Akdeniz University Clinical Research Ethics Committee of the Faculty of Medicine. Informed consent was taken from the healthy subjects in the control group and the thalassaemia major patients before their blood samples were collected. Signed parental permission was taken for subjects under the age of 18 year. Blood samples were taken from the patients and control subjects. Levels of selenium, zinc, copper, magnesium, and iron were measured. Control Group The control group (n = 20) was selected from healthy volunteers living in the Antalya region. A whole blood examination and haemoglobin electrophoresis were performed to exclude thalassaemia traits or any haemolytic anaemia for the controls. Patient Groups The thalassaemia major patients included in this study followed up with the Department of Paediatric Haematology, Akdeniz University Hospital, Antalya, Turkey. All the patients received regular blood transfusion and used iron chelation therapy as a monotherapy over 2 years. We also divided patients into three groups according to chelators therapy ((the
deferoxamine (Desferal, DFO) group, n = 19, aged 11– 32 years), (the deferiprone (Ferriprox, DFP) group, n = 20, aged 10–36 years) and (the deferasirox (Exjade, DFX) group, n = 21, aged 12–37 years)). The mean of the daily doses of DFO, DFP and DFX were 47.84 mg/kg/day, 76.32 mg/kg/day and 29.9 mg/kg/day, respectively. No patient received combined chelation therapy. Sample Collection Blood samples from the patients were collected just before the next transfusion. Blood samples of the patients and the controls for zinc, copper, magnesium, iron and ferritin were collected in serum tubes and sent to the clinical laboratory. Whole blood samples for selenium determination were collected in heparin tubes, centrifuged at 3000×g for 10 min at 4 °C, and separated plasma samples were stored at −80 °C until analysis. Measurement of Minerals Selenium levels were analysed by an ICP Mass Spectrometry (ICP-MS) (Parkin Elmer) (United States) system. Zinc levels were measured with a Shimadzu AA-7000 Atomic Absorption Spectrophotometer (Japan) system. Copper levels were measured by commercial kit according to the manufacturer’s instructions (FAR Diagnostic, Verona, Italy). Levels of magnesium and iron were measured with a Roche/Hitachi cobas 8000 (Switzerland) system. Ferritin levels were determined by electrochemiluminescence immunoassay method with a Roche/Hitachi cobas 8000 system. Statistical Analysis Statistical analysis was performed using SPSS software (Version 18.0, New York, USA). For data of normal distribution, one-way analysis of variance (ANOVA) procedures were used for comparisons among the different groups. To determine virtual difference in iron, copper and magnesium among the groups, we used Fisher’s least significant difference (LSD) for the significant result, and we also used Dunnett’s test in comparison with the controls. Group differences in haemoglobin, ferritin and zinc were tested using KruskalWallis test with post hoc Bonferroni test. Pairwise comparisons of the patient and control groups were performed using Mann–Whitney U test for nonparametric and ındependent T test for parametric data. Spearman’s rho correlation coefficient was calculated to test the relationship between variables. P values
