Ferritin heavy chain as main mediator of preventive effect of metformin against mitochondrial damage induced by doxorubicin in cardiomyocytes.
The efficacy of doxorubicin (DOX) as an antitumor agent is greatly limited by the induction of cardiomyopathy, which results from mitochondrial dysfunction and iron-catalyzed oxidative stress in the cardiomyocyte. Metformin (MET) has been seen to have a protective effect against the oxidative stress induced by DOX in cardiomyocytes through its modulation of ferritin heavy chain (FHC), the main iron-storage protein. This study aimed to assess the involvement of FHC as a pivotal molecule in the mitochondrial protection offered by MET against DOX cardiotoxicity. The addition of DOX to adult mouse cardiomyocytes (HL-1 cell line) increased the cytosolic and mitochondrial free iron pools in a time-dependent manner. Simultaneously, DOX inhibited complex I activity and ATP generation and induced the loss of mitochondrial membrane potential. The mitochondrial dysfunction induced by DOX was associated with the release of cytochrome c to the cytosol, the activation of caspase 3, and DNA fragmentation. The loss of iron homeostasis, mitochondrial dysfunction, and apoptosis induced by DOX were prevented by treatment with MET 24h before the addition of DOX. The involvement of FHC and NF-κB was determined through siRNA-mediated knockdown. Interestingly, the presilencing of FHC or NF-κB with specific siRNAs blocked the protective effect induced by MET against DOX cardiotoxicity. These findings were confirmed in isolated primary neonatal rat cardiomyocytes. In conclusion, these results deepen our knowledge of the protective action of MET against DOX-induced cardiotoxicity and suggest that therapeutic strategies based on FHC modulation could protect cardiomyocytes from the mitochondrial damage induced by DOX by restoring iron homeostasis.
Cardiology Department, University Hospital Virgen de la Arrixaca, 30120 Murcia, Spain; Department of Medicine, School of Medicine, University of Murcia, 30120 Murcia, Spain.
Mari C
MC
Asensio-Lopez
Cardiology Department, University Hospital Virgen de la Arrixaca, 30120 Murcia, Spain; Department of Medicine, School of Medicine, University of Murcia, 30120 Murcia, Spain.
Jesus
J
Sanchez-Mas
Cardiology Department, University Hospital Virgen de la Arrixaca, 30120 Murcia, Spain; Department of Medicine, School of Medicine, University of Murcia, 30120 Murcia, Spain.
Domingo A
DA
Pascual-Figal
Research Unit, University Hospital Virgen de la Arrixaca, 30120 Murcia, Spain.
Carlos
C
de Torre
Cardiology Department, University Hospital Virgen de la Arrixaca, 30120 Murcia, Spain; Department of Medicine, School of Medicine, University of Murcia, 30120 Murcia, Spain.
Mariano
M
Valdes
Cardiology Department, University Hospital Virgen de la Arrixaca, 30120 Murcia, Spain; Department of Medicine, School of Medicine, University of Murcia, 30120 Murcia, Spain. Electronic address: alax@um.es.
Antonio
A
Lax
D000818:Animals; D000831:Animals, Newborn; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D001052:Apoferritins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D002316:Cardiotonic Agents / Q000494:pharmacology*; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D045304:Cytochromes c / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D004317:Doxorubicin / Q000494:pharmacology*; D005786:Gene Expression Regulation; D007501:Iron / Q000378:metabolism; D008687:Metformin / Q000494:pharmacology*; D051379:Mice; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D051381:Rats; D015398:Signal Transduction
D000903:Antibiotics, Antineoplastic; D002316:Cardiotonic Agents; D016328:NF-kappa B; D034741:RNA, Small Interfering; D004317:Doxorubicin; D045304:Cytochromes c; D001052:Apoferritins; D008687:Metformin; D007501:Iron; D053148:Caspase 3
Cardiotoxicity; Doxorubicin; Ferritin; Free radicals; Iron homeostasis; Metformin; Mitochondrial function