NecroX‐5 suppresses sodium nitroprusside‐induced cardiac cell death through inhibition of JNK and caspase‐3 activation

Abstract

Although sodium nitroprusside (SNP) is an effective hypotensive drug and is often used in pediatric intensive care units and to treat acute heart failure, clinical application of SNP is limited by its cardiotoxicity. NecroX-5 (NX-5) was recently developed and has the capacity to inhibit necrotic cell death. No current literature addresses whether NX-5 suppresses SNP-induced cell death or its mechanism of action. We have investigated the protective role of NX-5 against SNP-induced cell death in cardiomyocyte-like H9c2 cells. SNP treatment induced severe cell death, possibly through phosphorylation of stress-activated protein kinase/c-Jun NH₂-terminal kinase (JNK) and activation of the apoptotic signaling pathway, including downregulation of Bcl-2 and cleavage of caspase-3. However, NX-5 suppresses SNP-induced cell death through inhibition of JNK activation and suppression of both downregulation of Bcl-2 protein expression and caspase-3 cleavage. These findings will provide insights and facilitate development of antidotes to SNP toxicity in cardiac cells.

Low abundance of mitochondrial DNA changes mitochondrial status and renders cells resistant to serum starvation and sodium nitroprusside insult

“…It has been suggested that the mitochondria serve as a metabolizer and target of nitrite, a nitric oxide metabolite (Shiva, ), and influence the responses to environmental pollutants, or drugs (Meyer et al, ). Therefore, we tested the toxicity of an excess of sodium nitroprusside (Lee et al, ), an exogenous nitric oxide donor in naïve H9c2 cells and H9c2 rho(0) cells. As shown in Figure A, 2 mM sodium nitroprusside caused severe cellular in naïve H9c2 cells while H9c2 rho(0) cells were highly resistant against same concentrations of the insult.…”

“…There was no significant difference in the levels of Bcl‐2 in H9c naïve and H9c2 rho(0). Anti‐apoptotic Bcl‐2 inhibits mitochondria‐driven cell death and this reduction of Bcl‐2 is induced in sodium nitroprusside mediated cell death (Lee et al, ). In line with this, the result from Figure B showed that the reduction of Bcl‐2 by sodium nitroprusside insult was highly suppressed in H9c2 rho(0) cells.…”

“…Cells were seeded on 96‐well tissue culture plates (2 × 10 4 cells/well). The viability was measured via quantitative colorimetric assay by using MTT (3‐[4,5‐dimethylthiazol‐2‐yl]‐2,5‐diphenyltetrazolium bromide) as previously described (Lee et al, ). The extent of MTT reduction to formazan within the cells was quantified by measuring the optical density at 550 nm using a Molecular Devices microplate reader (Menlo Park, CA).…”

“…Using these cells, we measured several mitochondrial parameters including changes in the mitochondrial membrane potential (MMP), mass, and Ca 2+ and Zn 2+ contents. In addition, we studied the sensitivity of the cells to serum starvation and sodium nitroprusside insults that lead to the production of excess spontaneous nitric oxide (NO) and cyanide which damage the mitochondria (Lee et al, ).…”

The Protective Effect of NecroX-5 on Flap Survival and Ischemic Reperfusion Injury Inflammation in Rat Model

“…Significant improvement in the protection of cell and tissue has been showed against various injury factors, such as neomycin, nitroprusside, oxidative stress, and gentamicin [5][6][7]. Recently, the fundamental role of NecroX-5 in IRI in the heart and liver has been described, however, there has been no research to determine the molecular mechanisms underlying the inhibition of NecroX-5 in IRI [8,9].…”