Effect of iron deficiency on c-kit⁺ cardiac stem cells in vitro.

Abstract

Iron deficiency is a common comorbidity in chronic heart failure (CHF) which may exacerbate CHF. The c-kit⁺ cardiac stem cells (CSCs) play a vital role in cardiac function repair. However, much is unknown regarding the role of iron deficiency in regulating c-kit⁺ CSCs function. In this study, we investigated whether iron deficiency regulates c-kit⁺ CSCs proliferation, migration, apoptosis, and differentiation in vitro. All c-kit⁺ CSCs were isolated from adult C57BL/6 mice. The c-kit⁺ CSCs were cultured with deferoxamine (DFO, an iron chelator), mimosine (MIM, another iron chelator), or a complex of DFO and iron (Fe(III)), respectively. Cell migration was assayed using a 48-well chamber system. Proliferation, cell cycle, and apoptosis of c-kit⁺ CSCs were analyzed with BrdU labeling, population doubling time assay, CCK-8 assay, and flow cytometry. Caspase-3 protein level and activity were examined with Western blotting and spectrophotometric detection. The changes in the expression of cardiac-specific proteins (GATA-4,TNI, and β-MHC) and cell cycle-related proteins (cyclin D1, RB, and pRB) were detected with Western blotting. DFO and MIM suppressed c-kit⁺ CSCs proliferation and differentiation. They also modulated cell cycle and cardiac-specific protein expression. Iron chelators down-regulated the expression and phosphorylation of cell cycle-related proteins. Iron reversed those suppressive effects of DFO. DFO and MIM didn't affect c-kit⁺ CSCs migration and apoptosis. Iron deficiency suppressed proliferation and differentiation of c-kit⁺ CSCs. This may partly explain how iron deficiency affects CHF prognosis.