Cardioprotective effects of hyperkalemia during simulated ischemia/reperfusion in neonatal rat cardiomyocytes-Preservation of Na<SUP>+</SUP>/K<SUP>+</SUP>-ATPase activity-

Preconditioning in cultured cardiomyocytes elevates the expression of several protective genes including Glut-4 and heat shock protein (HSP)70. Hypoxia-inducible factor-1 (HIF-1) is known to mediate the transcriptional activation of hypoxia-responsive genes. In this study, we examined the effect of adenovirus-mediated expression of constitutively stable hybrid forms of HIF-1α on cardiomyocyte viability and gene expression. Cultured neonatal rat cardiomyocytes were subjected to simulated ischemia-reperfusion with or without preinfection with recombinant adenoviral vectors [Ad2/HIF-1α/herpes simplex virus protein VP16 and Ad2/HIF-1α/nuclear factor-κB (NF-κB)]. Cellular viability and mRNA levels of several cardioprotective genes were measured. We demonstrated that infection with Ad2/HIF-1α/VP16 and Ad2/HIF-1α/NF-κB mimicked the upregulation of the mRNA levels of vascular endothelial growth factor (VEGF), Glut-1, Glut-4, HSP70, and inducible NO synthase (iNOS) and the protection of cultured neonatal rat cardiomyocytes by late-phase preconditioning against simulated ischemia-reperfusion. The same dose of a control viral vector expressing no transgene had no effect. Preconditioning also elevated HIF-1α protein levels. These results suggest that adenovirus-mediated expression of HIF-1α/VP16 or HIF-1α/NF-κB, a constitutively stable hybrid transcriptional factor, protected cultured neonatal cardiomyocytes against simulated ischemia-reperfusion injury by inducing multiple protective genes.

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Percutaneous Intracoronary Delivery of Plasma Extracellular Vesicles Protects the Myocardium Against Ischemia-Reperfusion Injury in Canis

Hypertension ◽

10.1161/hypertensionaha.121.17574 ◽

2021 ◽

Vol 78 (5) ◽

pp. 1541-1554

Author(s):

Hongyun Wang ◽

Rusitanmujiang Maimaitiaili ◽

Jianhua Yao ◽

Yuling Xie ◽

Sujing Qiang ◽

...

Keyword(s):

Stem Cell ◽

Embryonic Stem Cell ◽

Human Embryonic Stem Cell ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Embryonic Stem ◽

Cardiomyocyte Apoptosis ◽

Neonatal Rat ◽

Rat Cardiomyocytes ◽

Neonatal Rat Cardiomyocytes

Plasma circulating extracellular vesicles (EVs) have been utilized as a potential therapeutic strategy to treat ischemic disease through intramyocardial injection (efficient but invasive) or tail vein injection (noninvasive but low cardiac retention). An effective and noninvasive delivery of EVs for future clinical use is necessary. The large animal (canine) model was complemented with a murine ischemia-reperfusion injury (IRI) model, as well as H9 human embryonic stem cell–induced cardiomyocytes or neonatal rat cardiomyocytes to investigate the effective delivery method and the role of plasma EVs in the IRI model. We further determine the crucial molecule within EVs that confers the cardioprotective role in vivo and in vitro and investigate the efficiency of CHP (cardiac homing peptide)-linked EVs in alleviating IRI. D-SPECT imaging showed that percutaneous intracoronary delivery of EVs reduced infarct extent in dogs. CHP-EVs further reduced IRI-induced cardiomyocyte apoptosis in mice and neonatal rat cardiomyocytes. Mechanistically, administration of EVs by percutaneous intracoronary delivery (in dog) and myocardial injection (in mice) just before reperfusion reduced infarct size of IRI by increasing miR-486 levels. miR-486–deleted EVs exacerbated oxygen-glucose deprivation/reoxygenation–induced human embryonic stem cell–induced cardiomyocytes and neonatal rat cardiomyocyte apoptosis. EV-miR-486 inhibited the PTEN (phosphatase and tensin homolog deleted on chromosome ten) expression and then promoted AKT (protein kinase B) activation in human embryonic stem cell–induced cardiomyocytes and neonatal rat cardiomyocytes. In conclusion, plasma-derived EVs convey miR-486 to the myocardium and attenuated IRI-induced infarction and cardiomyocyte apoptosis. CHP strategy was effective to improve cardiac retention of EVs in mice (in vivo) and dogs (ex vivo).

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Comparison of cardioprotective effects of labeled and unlabeled oleanoic acids with new BOPIM dye on primary neonatal rat cardiomyocytes following hypoxia/reoxygenation injury

Pharmacological Reports ◽

10.1016/j.pharep.2014.03.014 ◽

2014 ◽

Vol 66 (4) ◽

pp. 677-685 ◽

Cited By ~ 3

Author(s):

Sa Wang ◽

Hai-bo He ◽

Shu-zhang Xiao ◽

Jun-zhi Wang ◽

Cai-hong Bai ◽

...

Keyword(s):

Neonatal Rat ◽

Rat Cardiomyocytes ◽

Neonatal Rat Cardiomyocytes ◽

Reoxygenation Injury ◽

Cardioprotective Effects ◽

Hypoxia Reoxygenation

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Radicicol activates heat shock protein expression and cardioprotection in neonatal rat cardiomyocytes

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00921.2003 ◽

2004 ◽

Vol 287 (3) ◽

pp. H1081-H1088 ◽

Cited By ~ 34

Author(s):

Tina M. Griffin ◽

Tina V. Valdez ◽

Ruben Mestril

Keyword(s):

Heat Shock ◽

Transcriptional Activation ◽

Cardiac Tissue ◽

Defense Mechanism ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Neonatal Rat ◽

Heat Shock Factor 1 ◽

Rat Cardiomyocytes ◽

Neonatal Rat Cardiomyocytes

Heat shock proteins (HSPs) constitute an endogenous cellular defense mechanism against environmental stresses. In the past few years, studies have shown that overexpression of HSPs can protect cardiac myocytes against ischemia-reperfusion injury. In an attempt to increase the HSPs in cardiac tissue, we used the compound radicicol that activates HSP expression by binding to the HSP 90 kDa (HSP90). HSP90 is the main component of the cytosolic molecular chaperone complex, which has been implicated in the regulation of the heat shock factor 1 (HSF1). HSF1 is responsible for the transcriptional activation of the heat shock genes. In the present study, we show that radicicol induces HSP expression in neonatal rat cardiomyocytes, and this increase in HSPs confers cardioprotection to these cardiomyocytes. We also show that radicicol induction of the HSP and cardioprotection is dependent on the inhibition of HSP90 in cardiomyocytes. These results indicate that modulation of the active HSP90 protein level plays an important role in cardioprotection. Therefore, compounds, such as radicicol and its possible derivatives that inhibit the function of HSP90 in the cell may represent potentially useful cardioprotective agents.

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