Induced pluripotent stem cell-derived mesenchymal stem cells exert growth differentiation factor-15-dependent paracrine effect in cigarette smoke medium-induced cardiomyocyte injury

Abstract

Introduction: Mesenchymal stem cells (MSCs) are emerging as a potential cell-based therapy for cardiovascular diseases (CVDs), in which cigarette smoking is the major risk factor. Our previous findings demonstrated that the secretions from human induced pluripotent stem cell–derived mesenchymal stem cells (iPSC-MSCs) had a superior effect over bone marrow–derived MSCs (BM-MSCs) in attenuating cigarette smoke medium (CSM)–induced cardiomyocytes injury. Secretions of iPSC-MSCs contain higher level of growth differentiation factor-15 (GDF-15) than BM-MSCs,1 which has been regarded as a cardioprotective protein against cell apoptosis. The aim of this study was to investigate whether GDF-15 is responsible for the superior therapeutic effects of secretions from iPSC-MSCs. Methods: The human AC16 cardiomyocyte cell line was cultured in DMEM/F12 containing 12.5% fetal bovine serum. The CSM and conditioned medium (CdM) from iPSC-MSCs or recombinant human GDF-15 (rhGDF-15; same concentration as detected in CdM from iPSC-MSC) were added into cells and incubated for 24 hours. Cells were harvested to perform H2DCF-DA and MitoSox Red assays to determine cellular reactive oxygen species (ROS) and mitochondrial superoxide by flow cytometry. Apoptotic cells were measured with Annexin V apoptosis detection kit. JC-1 assay was conducted on cells to measure mitochondrial membrane potential. Results: CdM from iPSC-MSC had a superior effect on the inhibition of CSM-induced cell apoptosis than that from BM-MSCs, along with reduced cleaved caspase 3 and cleaved PARP. CdM from iPSC-MSCs or rhGDF-15 significantly reduced CSM-induced ROS, mitochondrial superoxide production and cell apoptosis, respectively. Recombinant hGDF-15 partially restored mitochondrial function by maintaining mitochondrial membrane potential compared to CdM from iPSC-MSCs. Conclusion: These data suggest that iPSC-MSCs-mediated protective effects on cardiomyocytes by inhibiting cell apoptosis and oxidative stress and attenuating mitochondrial dysfunction are likely to be GDF-15-dependent paracrine action in vitro. Reference 1. Zhang Y, Liang X, Liao S, et al. Potent Paracrine Effects of human induced Pluripotent Stem Cell-derived Mesenchymal Stem Cells Attenuate Doxorubicin-induced Cardiomyopathy. Sci Rep 2015;5:11235.