Yu Liu1, Jie Wang2, Shu-Ying Qi3, Lei-Sheng Ru3, Chao Ding3, Hai-Jun Wang4, Jing-Shan Zhao5, Jing-Jing Li3, Ai-Ying Li5, Dong-Mei Wang6. 1. Department of Cardiology, Peace Hospital of People's Liberation Army, Shijiazhuang, Hebei, China; Department of Biochemistry and Molecular Biology, School of Basic Medicine, Laboratory of Medical Biotechnology of Hebei Province, Hebei Traditional Chinese Medical College, Shijiazhuang, Hebei, China. 2. Division of Cardiology, Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York, USA. 3. Department of Cardiology, Peace Hospital of People's Liberation Army, Shijiazhuang, Hebei, China. 4. Department of Surgery, The Fourth Affiliated Hospital of Hebei Medical University, Shijiazhuang, Hebei, China. 5. Department of Biochemistry and Molecular Biology, School of Basic Medicine, Laboratory of Medical Biotechnology of Hebei Province, Hebei Traditional Chinese Medical College, Shijiazhuang, Hebei, China. 6. Department of Cardiology, Peace Hospital of People's Liberation Army, Shijiazhuang, Hebei, China. Electronic address: slwangdm@126.com.
Abstract
BACKGROUND: Endoplasmic reticulum (ER) stress plays an important role in mediating ischemic heart cell death. The aim of this study was to investigate whether manipulation of a key factor of the ER stress pathway, eukaryotic translation initiation factor 2 subunit α (eIF2α), can change the natural history of heart failure (HF). METHODS: HF was induced using coronary artery ligation in adult rats and a selective eIF2α dephosphorylation inhibitor, salubrinal (Sal), was used. Thirty minutes after ligation, rats were randomly assigned to 3 groups: myocardial infarction (MI) plus placebo injections (dimethyl sulfoxide; n = 12), MI plus Sal injection (Sal; n = 12), and MI (HF; n = 12). Hemodynamic parameters were examined. Hearts were harvested for apoptosis assessment after 8 weeks of Sal treatment by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labelling and flow cytometric analysis. Hearts were harvested to determine ER chaperones by Western analysis, real-time polymerase chain reaction and immunohistochemical analysis. RESULTS: Cardiac function was significantly improved in Sal-treated rats. Apoptosis was reduced by Sal treatment. Glucose-regulated protein-78 and -94 were increased in HF but normalized by Sal treatment. HF caused a significant increase in eIF2α phosphorylation, which was further increased by Sal treatment, and caspase-12 and phospho-c-JUN NH2-terminal kinase were markedly increased in rats with HF alone but significantly reduced by Sal treatment. CONCLUSIONS: Our results suggest that reduction of ER stress and myocardial apoptosis through inhibition of eIF2α dephosphorylation might alter the natural history of HF, which might provide a new approach for its treatment.
BACKGROUND: Endoplasmic reticulum (ER) stress plays an important role in mediating ischemic heart cell death. The aim of this study was to investigate whether manipulation of a key factor of the ER stress pathway, eukaryotic translation initiation factor 2 subunit α (eIF2α), can change the natural history of heart failure (HF). METHODS: HF was induced using coronary artery ligation in adult rats and a selective eIF2α dephosphorylation inhibitor, salubrinal (Sal), was used. Thirty minutes after ligation, rats were randomly assigned to 3 groups: myocardial infarction (MI) plus placebo injections (dimethyl sulfoxide; n = 12), MI plus Sal injection (Sal; n = 12), and MI (HF; n = 12). Hemodynamic parameters were examined. Hearts were harvested for apoptosis assessment after 8 weeks of Sal treatment by terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labelling and flow cytometric analysis. Hearts were harvested to determine ER chaperones by Western analysis, real-time polymerase chain reaction and immunohistochemical analysis. RESULTS: Cardiac function was significantly improved in Sal-treated rats. Apoptosis was reduced by Sal treatment. Glucose-regulated protein-78 and -94 were increased in HF but normalized by Sal treatment. HF caused a significant increase in eIF2α phosphorylation, which was further increased by Sal treatment, and caspase-12 and phospho-c-JUN NH2-terminal kinase were markedly increased in rats with HF alone but significantly reduced by Sal treatment. CONCLUSIONS: Our results suggest that reduction of ER stress and myocardial apoptosis through inhibition of eIF2α dephosphorylation might alter the natural history of HF, which might provide a new approach for its treatment.
Authors: Aric F Logsdon; Brandon P Lucke-Wold; Linda Nguyen; Rae R Matsumoto; Ryan C Turner; Charles L Rosen; Jason D Huber Journal: Brain Res Date: 2016-04-27 Impact factor: 3.252
Authors: Man Liu; Guangbin Shi; Anyu Zhou; Cassady E Rupert; Kareen L K Coulombe; Samuel C Dudley Journal: J Mol Cell Cardiol Date: 2018-02-21 Impact factor: 5.000