title: Cisplatin compromises myocardial contractile function and mitochondrial ultrastructure: role of endoplasmic reticulum stress.
abstract: 1. Cisplatin is a potent chemotherapeutic agent with broad-spectrum antineoplastic activity against various types of tumours. However, a major factor limiting treatment with cisplatin is its acute and cumulative cardiotoxicity. The aim of the present study was to explore the effect of cisplatin on myocardial contractile function and the possible underlying cellular mechanisms. 2. C57 mice were treated with cisplatin (10 mg/kg per day, i.v.) or vehicle (0.9% NaCl) for 1 week and myocardial function was assessed using the Langendorff and cardiomyocyte edge-detection systems. Transmission electron microscopy, mitochondrial membrane potential, indices of endoplasmic reticulum (ER) stress and caspase 3 activity were evaluated. 3. Cisplatin-treated mice developed myocardial contractile dysfunction, as evidenced by a reduction in left ventricular developed pressure (LVDP) and the first derivative of LVDP (+/-dP/dt). Cisplatin treatment significantly prolonged time to 90% relengthening, depressed peak shortening, maximal velocity of shortening/relengthening (+/-dL/dt) and augmented the frequency-elicited depression in peak shortening. The JC-1 fluorescent assay demonstrated that cispatin-induced cardiac dysfunction was associated with mitochondrial membrane depolarization. Transmission electron microscopy revealed that cisplatin induces ultrastructural abnormalities of the mitochondria. Following cisplatin treatment, cardiomyocytes show activation of the ER stress response, increased caspase 3 activity and increased terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL) staining. 4. The data indicate that cisplatin is cardiotoxic and may lead to left ventricular dysfunction and depressed cardiomyocyte contraction associated with mitochondrial abnormalities, enhanced ER stress and apoptosis. This work should shed some light on the management of cisplatin-induced cardiac injury.
authors.affiliation: Division of Pharmaceutical Science, Center for Cardiovascular Research and Alternative Medicine, University of Wyoming, Laramie, WY 82071, USA. hma2@uwyo.edu
authors.forename: Heng
authors.initials: H
authors.lastname: Ma
authors.forename: Kyla R
authors.initials: KR
authors.lastname: Jones
authors.forename: Rui
authors.initials: R
authors.lastname: Guo
authors.forename: Peisheng
authors.initials: P
authors.lastname: Xu
authors.forename: Youqing
authors.initials: Y
authors.lastname: Shen
authors.forename: Jun
authors.initials: J
authors.lastname: Ren
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000633:toxicity*; D017209:Apoptosis / Q000187:drug effects; D054715:Cardiotoxins / Q000633:toxicity*; D053148:Caspase 3 / Q000378:metabolism; D048430:Cell Shape / Q000187:drug effects; D002478:Cells, Cultured; D002945:Cisplatin / Q000633:toxicity*; D003864:Depression, Chemical; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000648:ultrastructure; D006321:Heart / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects; D008297:Male; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D008929:Mitochondria, Heart / Q000187:drug effects* / Q000648:ultrastructure; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000166:cytology / Q000473:pathology; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000201:enzymology / Q000502:physiology / Q000648:ultrastructure; D009929:Organ Size / Q000187:drug effects; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D054715:Cardiotoxins; D053148:Caspase 3; D002945:Cisplatin