Cardiotoxicity In H9c2 Cells Research Articles

Salvianolic Acid A Protects H9c2 Cells from Arsenic Trioxide-Induced Injury via Inhibition of the MAPK Signaling Pathway

Background/Aims: This study aimed to investigate whether Salvianolic acid A (Sal A) conferred cardiac protection against Arsenic trioxide (ATO)-induced cardiotoxicity in H9c2 cells by inhibiting MAPK pathways activation. Methods: H9c2 cardiac cells were exposed to 10 µM ATO for 24 h to induce cytotoxicity. The cells were pretreated with Sal A for 4 h before exposure to ATO. Cell viability was determined utilizing the MTT assay. The percentage of apoptosis was measured by a FITC-Annexin V/PI apoptosis kit for flow cytometry. Mitochondrial membrane potential (∆Ψm) was detected by JC-1. The intracellular ROS levels were measured using an Image-iT^TM LIVE Green Reactive Oxygen Species Detection Kit. The apoptosis-related proteins and the MAPK signaling pathways proteins expression were quantified by Western blotting. Results: Sal A pretreatment increased cell viability, suppressed ATO-induced mitochondrial membrane depolarization, and significantly altered the apoptotic rate by enhancing endogenous antioxidative enzyme activity and ROS generation. Signal transduction studies indicated that Sal A suppressed the ATO-induced activation of the MAPK pathway. More importantly, JNK, ERK, and p38 inhibitors mimicked the cytoprotective activity of Sal A against ATO-induced injury in H9c2 cells by increasing cell viability, up-regulating Bcl-2 protein expression, and down-regulating both Bax and caspase-3 protein expression. Conclusion: Sal A decreases the ATO-induced apoptosis and necrosis of H9c2 cells, and the underlying mechanisms of this protective effect of Sal A may be connected with the MAPK pathways.

Resveratrol prevents doxorubicin-induced cardiotoxicity in H9c2 cells through the inhibition of endoplasmic reticulum stress and the activation of the Sirt1 pathway.

Treatment with doxorubicin (DOX) is one of the major causes of chemotherapy-induced cardiotoxicity and is therefore, the principal limiting factor in the effectiveness of chemotherapy for cancer patients. DOX‑induced heart failure is thought to result from endoplasmic reticulum (ER) stress and cardiomyocyte apoptosis. Resveratrol (RV), a polyphenol antioxidant found in red wine, has been shown to play a cardioprotective role. The aim of the present study was to examine the effects of RV on DOX‑induced cardiotoxicity in H9c2 cells. We hypothesized that RV would protect H9c2 cells against DOX‑induced ER stress and subsequent cell death through the activation of the Sirt1 pathway. Our results demonstrated that the decrease observed in the viability of the H9c2 cells following exposure to DOX was accompanied by a significant increase in the expression of the ER stress‑related proteins, glucose‑regulated protein 78 (GRP78) and C/EBP homologous protein (CHOP). However, we found that RV downregulated the expression of ER stress marker protein in the presence of DOX and restored the viability of the H9c2 cells. Exposure to RV or DOX alone only slightly increased the protein expression of Sirt1, whereas a significant increase in Sirt1 protein levels was observed in the cells treated with both RV and DOX. The Sirt1 inhibitor, nicotinamide (NIC), partially neutralized the effects of RV on the expression of Sirt1 in the DOX‑treated cells and completely abolished the effects of RV on the expression of GRP78 and CHOP. The findings of our study suggest that RV protects H9c2 cells against DOX‑induced ER stress through ER stabilization, and more specifically through the activation of the Sirt1 pathway, thereby leading to cardiac cell survival.

Mechanistic study on the cardioprotective and chemosensitizing effects of a novel danshensu derivative

Doxorubicin (Dox) is an anthracycline antibiotic which is widely used in clinics as an anticancer agent. However, the use of Dox is limited by its cardiotoxicity. Our previous studies have shown that a Danshensu derivative ADTM displayed strong cardioprotective effects in an oxidative stress-induced cell injury model in H9c2 cardiomyocytes and an acute myocardial ischemia model in rat [1]. We are developing more potent cardioprotective danshensu derivative based on ADTM structure for management of the cardiotoxic side effect of Dox. In the present study, we investigated the protective and chemosensitizing effects of a novel Danshensu derivative D006 against cardiotoxicity induced by Dox and in increasing the antitumor activity of Dox respectively. Our results showed that D006 was approximately 30-fold more potent than ADTM in ameliorating Dox-induced cardiotoxicity in H9c2 cells. In the zebrafish model, D006 but not ADTM or Danshensu alone, significantly preserved stroke volume of heart function after Dox treatment. In addition, D006 enhanced Dox-induced apoptosis as well as ROS production in MCF-7 tumor cells. Mitochondrial biogenesis, a process involved in the formation of new mitochondrial, which depends on the expression of PGC-1. Recent studies showed that suppressed cardiac mitochondrial biogenesis and decreased mtDNA contents may play vital roles in the pathogenesis of Dox induced cardiomyopathy [2]. Further mechanistic studies verified that D006 increased the expression of PGC-1β in H9c2 cells. Moreover, D006 upregulated mitochondrial biogenesis and increased mtDNA copy number after Dox treatment in H9c2 cells. Our results revealed that a new danshensu derivative displayed promising cardioprotective effects against Dox induced cardiotoxicity both in vivo and in vitro, at least partially through activating mitochondrial biogenesis. In addition, the new danshensu derivative also potentiated the anticancer effects of Dox in breast tumor cells.

Polyphenol-rich apple (Malus domestica L.) peel extract attenuates arsenic trioxide induced cardiotoxicity in H9c2 cells via its antioxidant activity

Evidences suggest that apple peel has a wide range of polyphenols having antioxidant activity and its consumption has been linked with improved health benefits. Arsenic trioxide (ATO) is a very effective drug for the treatment of acute promyelocytic leukemia (APL) but it leads to cardiotoxicity mediated through alterations in various cardiac ion channels and by increasing the intracellular calcium level and reactive oxygen species (ROS). The aim of the present investigation was to study the effect of methanolic extract of apple peel (APME) and aqueous extract of apple peel (APAE) on ATO (5 μM) induced toxicity in the H9c2 cardiac myoblast cell line. We estimated the cellular status of innate antioxidant enzymes, level of ROS, mitochondrial superoxide, glutathione and intracellular calcium with ATO and apple peel extracts. Prior to the cell line based study, we had evaluated the antioxidant potential of apple peel extract by 1,1-diphenyl-2-picrylhydrazyl (DPPH), total reducing power (TRP), superoxide anion and hydroxyl radical scavenging activity, in addition to quantifying total phenolic and flavonoid content. Both the extracts showed considerable antioxidant activity in cell-free chemical assays. In addition, both APME and APAE prevented the alteration in antioxidant status induced by ATO in H9c2 cells. Significant differential alterations had been observed in the activity of lactate dehydrogenase, superoxide dismutase, catalase, glutathione, glutathione peroxidase, thioredoxin reductase, xanthine oxidase, calcium overload and caspase3 activity with ATO. The overall result revealed the protective property of polyphenol-rich apple peel extract against ATO induced cardiac toxicity via its antioxidant activity.