title: Kaempferol protects cardiomyocytes against anoxia/reoxygenation injury via mitochondrial pathway mediated by SIRT1.
abstract: Mitochondria-mediated apoptosis is a critical mechanism of anoxia/ reoxygenation (A/R)-induced injury in cardiomyocytes. Kaempferol (Kae) is a natural polyphenol and a type of flavonoid, which has been demonstrated to protect myocardium against ischemia/reperfusion (I/R) injury. However, the mechanism is still not fully elucidated. We hypothesize that Kae may improve the mitochondrial function during I/R injury via a potential signal pathway. In this study, an in vitro I/R model was replicated on neonatal rat primary cardiomyocytes by A/R treatment. Cell viability was monitored by the 3-(4,5-dimethylthiazol- 2-yl)-5-(3- carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium (MTS) assay. The levels of intracellular reactive oxygen species, mitochondrial membrane potential (Δψm) and apoptosis were determined by flow cytometry. Protein expression was detected by Western Blotting. mPTP opening and the activity of caspase-3 were measured by colorimetric method. The results showed that Kae effectively enhanced the cell viability and decreased the LDH release in cardiomyocytes subjected to A/R injury. Kae reduced the A/R-induced reactive oxygen species generation, the loss of Δψm, and the release of cytochrome c from mitochondria into cytosol. Kae inhibited the A/R-stimulated mPTP opening and activation of caspase-3, and ultimate decrease in cardiomyocytes apoptosis. Furthermore, we found Kae up-regulated Human Silent Information Regulator Type 1 (SIRT1) expression, indicating SIRT1 signal pathway likely involved the cardioprotection of Kae. Sirtinol, a SIRT1 inhibitor, abolished the protective effect of Kae in cardiomyocytes subjected to A/R. Additionally, Kae significantly increased the expression of Bcl-2. Thus, we firstly demonstrate that Kae protects cardiomyocytes against A/R injury through mitochondrial pathway mediated by SIRT1.
authors.affiliation: Department of Pharmacology & Molecular Therapeutics, Nanchang University School of Pharmaceutical Science, Nanchang 330006, PR China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Department of Pharmacology & Molecular Therapeutics, Nanchang University School of Pharmaceutical Science, Nanchang 330006, PR China.
authors.forename: Zhangping
authors.initials: Z
authors.lastname: Liao
authors.affiliation: Department of Pharmacology & Molecular Therapeutics, Nanchang University School of Pharmaceutical Science, Nanchang 330006, PR China.
authors.forename: Liqing
authors.initials: L
authors.lastname: Huang
authors.affiliation: Department of Pharmacology & Molecular Therapeutics, Nanchang University School of Pharmaceutical Science, Nanchang 330006, PR China.
authors.forename: Dan
authors.initials: D
authors.lastname: Liu
authors.affiliation: Jiangxi Provincial Key Laboratory of Molecular Medicine at the Second Affiliated Hospital, Nanchang University, Nanchang 330006, PR China.
authors.forename: Dong
authors.initials: D
authors.lastname: Yin
authors.affiliation: Department of Pharmacology & Molecular Therapeutics, Nanchang University School of Pharmaceutical Science, Nanchang 330006, PR China. Electronic address: jxhm56@hotmail.com.
authors.forename: Ming
authors.initials: M
authors.lastname: He
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D045304:Cytochromes c / Q000378:metabolism; D019610:Cytoprotection; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D044949:Kaempferols / Q000494:pharmacology*; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008929:Mitochondria, Heart / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D033681:Mitochondrial Membrane Transport Proteins / Q000187:drug effects / Q000378:metabolism; D000083162:Mitochondrial Permeability Transition Pore; D015428:Myocardial Reperfusion Injury / Q000201:enzymology / Q000473:pathology / Q000517:prevention & control*; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D056564:Sirtuin 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: D056572:Histone Deacetylase Inhibitors; D044949:Kaempferols; D033681:Mitochondrial Membrane Transport Proteins; D000083162:Mitochondrial Permeability Transition Pore; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; C006552:kaempferol; D045304:Cytochromes c; D007770:L-Lactate Dehydrogenase; C505410:Casp3 protein, rat; D053148:Caspase 3; C488368:Sirt1 protein, rat; D056564:Sirtuin 1
keywords: Anoxia/reoxygenation; Cardiomyocyte; Kaempferol; Mitochondrial; SIRT1