Dataset Information

Iron deficiency impairs contractility of human cardiomyocytes through decreased mitochondrial function.

ABSTRACT:

Aims

Iron deficiency is common in patients with heart failure and associated with a poor cardiac function and higher mortality. How iron deficiency impairs cardiac function on a cellular level in the human setting is unknown. This study aims to determine the direct effects of iron deficiency and iron repletion on human cardiomyocytes.

Methods and results

Human embryonic stem cell-derived cardiomyocytes were depleted of iron by incubation with the iron chelator deferoxamine (DFO). Mitochondrial respiration was determined by Seahorse Mito Stress test, and contractility was directly quantified using video analyses according to the BASiC method. The activity of the mitochondrial respiratory chain complexes was examined using spectrophotometric enzyme assays. Four days of iron depletion resulted in an 84% decrease in ferritin (P < 0.0001) and significantly increased gene expression of transferrin receptor 1 and divalent metal transporter 1 (both P < 0.001). Mitochondrial function was reduced in iron-deficient cardiomyocytes, in particular ATP-linked respiration and respiratory reserve were impaired (both P < 0.0001). Iron depletion affected mitochondrial function through reduced activity of the iron-sulfur cluster containing complexes I, II and III, but not complexes IV and V. Iron deficiency reduced cellular ATP levels by 74% (P < 0.0001) and reduced contractile force by 43% (P < 0.05). The maximum velocities during both systole and diastole were reduced by 64% and 85%, respectively (both P < 0.001). Supplementation of transferrin-bound iron recovered functional and morphological abnormalities within 3 days.

Conclusion

Iron deficiency directly affects human cardiomyocyte function, impairing mitochondrial respiration, and reducing contractility and relaxation. Restoration of intracellular iron levels can reverse these effects.

SUBMITTER: Hoes MF

PROVIDER: S-EPMC5993224 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Iron deficiency impairs contractility of human cardiomyocytes through decreased mitochondrial function.

Hoes Martijn F MF Grote Beverborg Niels N Kijlstra J David JD Kuipers Jeroen J Swinkels Dorine W DW Giepmans Ben N G BNG Rodenburg Richard J RJ van Veldhuisen Dirk J DJ de Boer Rudolf A RA van der Meer Peter P

European journal of heart failure 20180227 5

<h4>Aims</h4>Iron deficiency is common in patients with heart failure and associated with a poor cardiac function and higher mortality. How iron deficiency impairs cardiac function on a cellular level in the human setting is unknown. This study aims to determine the direct effects of iron deficiency and iron repletion on human cardiomyocytes.<h4>Methods and results</h4>Human embryonic stem cell-derived cardiomyocytes were depleted of iron by incubation with the iron chelator deferoxamine (DFO). ...[more]

PMID: 29484788

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Dataset Information

Iron deficiency impairs contractility of human cardiomyocytes through decreased mitochondrial function.

Aims

Methods and results

Conclusion

Publications

Iron deficiency impairs contractility of human cardiomyocytes through decreased mitochondrial function.

Similar Datasets

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