Model Of DOX-induced Cardiotoxicity Research Articles

Therapeutic effects of higenamine combined with [6]-gingerol on chronic heart failure induced by doxorubicin via ameliorating mitochondrial function.

Higenamine (HG) is a natural benzylisoquinoline alkaloid isolated from Aconitum with positive inotropic and chronotropic effects. This study aimed to investigate the possible cardioprotective effects of HG combined with [6]‐gingerol (HG/[6]‐GR) against DOX‐induced chronic heart failure (CHF) by comprehensive approaches. DOX‐induced cardiotoxicity model in rats and H9c2 cells was established. Therapeutic effects of HG/[6]‐GR on haemodynamics, serum indices and histopathology of cardiac tissue were analysed. Cell mitochondrial energy phenotype and cell mitochondrial fuel flex were measured by a Seahorse XFp analyser. Moreover, UHPLC‐Q‐TOF/MS was performed to explore the potential metabolites affecting the therapeutic effects and pathological process of CHF. To further investigate the potential mechanism of HG/[6]‐GR, mRNA and protein expression levels of RAAS and LKB1/AMPK/Sirt1‐related pathways were detected. The present data demonstrated that the therapeutic effects of HG/[6]‐GR combination on CHF were presented in ameliorating heart function, down‐regulation serum indices and alleviating histological damage of heart tissue. Besides, HG/[6]‐GR has an effect on increasing cell viability of H9c2 cells, ameliorating DOX‐induced mitochondrial dysfunction and elevating mitochondrial OCR and ECAR value. Metabolomics analyses showed that the therapeutic effect of HG/[6]‐GR combination is mainly associated with the regulation of fatty acid metabolites and energy metabolism pathways. Furthermore, HG/[6]‐GR has an effect on down‐regulating RAAS pathway‐related molecules and up‐regulating LKB1/AMPKα/Sirt1‐related pathway. The present work demonstrates that HG/[6]‐GR prevented DOX‐induced cardiotoxicity via the cardiotonic effect and promoting myocardial energy metabolism through the LKB1/AMPKα/Sirt1 signalling pathway, which promotes mitochondrial energy metabolism and protects against CHF.

MiR-200a Attenuated Doxorubicin-Induced Cardiotoxicity through Upregulation of Nrf2 in Mice.

Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) was closely involved in doxorubicin- (DOX-) induced cardiotoxicity. MicroRNA-200a (miR-200a) could target Keap1 mRNA and promote degradation of Keap1 mRNA, resulting in Nrf2 activation. However, the role of miR-200a in DOX-related cardiotoxicity remained unclear. Our study is aimed at investigating the effect of miR-200a on DOX-induced cardiotoxicity in mice. For cardiotropic expression, male mice received an injection of an adeno-associated virus 9 (AAV9) system carrying miR-200a or miR-scramble. Four weeks later, mice received a single intraperitoneal injection of DOX at 15 mg/kg. In our study, we found that miR-200a mRNA was the only microRNA that was significantly decreased in DOX-treated mice and H9c2 cells. miR-200a supplementation blocked whole-body wasting and heart atrophy caused by acute DOX injection, decreased the levels of cardiac troponin I and the N-terminal probrain natriuretic peptide, and improved cardiac and adult cardiomyocyte contractile function. Moreover, miR-200a reduced oxidative stress and cardiac apoptosis without affecting matrix metalloproteinase and inflammatory factors in mice with acute DOX injection. miR-200a also attenuated DOX-induced oxidative injury and cell loss in vitro. As expected, we found that miR-200a activated Nrf2 and Nrf2 deficiency abolished the protection provided by miR-200a supplementation in mice. miR-200a also provided cardiac benefits in a chronic model of DOX-induced cardiotoxicity. In conclusion, miR-200a protected against DOX-induced cardiotoxicity via activation of the Nrf2 signaling pathway. Our data suggest that miR-200a may represent a new cardioprotective strategy against DOX-induced cardiotoxicity.

MiR-451 Silencing Inhibited Doxorubicin Exposure-Induced Cardiotoxicity in Mice.

Oxidative stress and cardiomyocytes apoptosis were closely involved in the pathological process of doxorubicin- (Dox-) induced cardiac injury. MicroRNA-451 (miR-451) was mainly expressed in cardiomyocytes. However, the role of miR-451 in Dox-induced cardiac injury remained unclear. Our study aimed to investigate the effect of miR-451 on Dox-induced cardiotoxicity in mice. We established a Dox-induced cardiotoxicity model in the mice and manipulated miR-451 expression in the heart using a miR-451 inhibitor, which was injected every other day beginning at one day before Dox injection. Oxidative stress and apoptosis in the hearts were evaluated. miR-451 levels were significantly increased in Dox-treated mice or cardiomyocytes. miR-451 inhibition attenuated Dox-induced whole-body wasting and heart atrophy, reduced cardiac injury, restored cardiac function, and improved cardiomyocyte contractile function. Moreover, miR-451 inhibition reduced oxidative stress and cardiomyocytes apoptosis in vivo and in vitro. miR-451 inhibition increased the expression of calcium binding protein 39 (Cab39) and activated adenosine monophosphate activated protein kinase (AMPK) signaling pathway. A specific inhibitor of AMPK abolished the protection provided by miR-451 inhibition against cell injury in vitro. In conclusion, miR-451 inhibition protected against Dox-induced cardiotoxicity via activation of AMPK signaling pathway.

FNDC5 alleviates oxidative stress and cardiomyocyte apoptosis in doxorubicin-induced cardiotoxicity via activating AKT

Oxidative stress and cardiomyocyte apoptosis play critical roles in doxorubicin (DOX)-induced cardiotoxicity. Previous studies indicated that fibronectin type III domain-containing 5 (FNDC5) and its cleaved form, irisin, could preserve mitochondrial function and attenuate oxidative damage as well as cell apoptosis, however, its role in DOX-induced cardiotoxicity remains unknown. Our present study aimed to investigate the role and underlying mechanism of FNDC5 on oxidative stress and cardiomyocyte apoptosis in DOX-induced cardiotoxicity. Cardiomyocyte-specific FNDC5 overexpression was achieved using an adeno-associated virus system, and then the mice were exposed to a single intraperitoneal injection of DOX (15 mg/kg) to generate DOX-induced cardiotoxicity. Herein, we found that FNDC5 expression was downregulated in DOX-treated murine hearts and cardiomyocytes. Fndc5 deficiency resulted in increased oxidative damage and apoptosis in H9C2 cells under basal conditions, imitating the phenotype of DOX-induced cardiomyopathy in vitro, conversely, FNDC5 overexpression or irisin treatment alleviated DOX-induced oxidative stress and cardiomyocyte apoptosis in vivo and in vitro. Mechanistically, we identified that FNDC5/Irisin activated AKT/mTOR signaling and decreased DOX-induced cardiomyocyte apoptosis, and moreover, we provided direct evidence that the anti-oxidant effect of FNDC5/Irisin was mediated by the AKT/GSK3β/FYN/Nrf2 axis in an mTOR-independent manner. And we also demonstrated that heat shock protein 20 was responsible for the activation of AKT caused by FNDC5/Irisin. In line with the data in acute model, we also found that FNDC5/Irisin exerted beneficial effects in chronic model of DOX-induced cardiotoxicity (5 mg/kg, i.p., once a week for three times, the total cumulative dose is 15 mg/kg) in mice. Based on these findings, we supposed that FNDC5/Irisin was a potential therapeutic agent against DOX-induced cardiotoxicity.

Plasmatic and chamber-specific modulation of cardiac microRNAs in an acute model of DOX-induced cardiotoxicity

BackgroundDoxorubicin (DOX) is a chemotherapeutic drug limited in its usefulness by an adverse side effect, cardiotoxicity. The mechanisms leading to this detrimental occurrence are not completely clear, and lately many authors focused their attention on the possible role of microRNAs (miRNAs), small regulators of cardiovascular functions, in this phenomenon. Notably, these molecules recently emerged also as potential circulating biomarkers of several cardiac diseases. Thus, the aim of this study was the simultaneous investigation of circulating and cardiac tissue miRNAs expression upon DOX treatment in vivo. MethodsTwenty C57BL/6 female mice were administered with 24 mg/Kg cumulative dose of DOX or saline (CTRL) for 2 weeks. Echocardiography was performed at baseline and at the end of treatment (T1). Plasma and heart samples were collected at T1, separating atria from left (LV) and right (RV) ventricles, and miRNAs expression was tested by RT-qPCR-based arrays. All putatively DOX-regulated candidates were then validated by single assays in vivo and then evaluated also in murine immortalized cardiomyocytes (HL-1) treated with 1 μM DOX for 24 h. In the end, bioinformatics target prediction was performed for all DOX-miRNAs. ResultsCardiotoxicity onset was diagnosed upon impairment of six cardiac functional parameters in DOX-treated mice at T1. Samples collection, followed by screening and validation steps, identified eleven miRNAs dysregulated by the drug in plasma, while seven resulted as altered in separate heart chambers. Interestingly, miR-34a-5p and miR-451a showed a dysregulation in both plasma and tissue samples of DOX-administered animals, whereas five additional miRNAs presented chamber specific modulation. Of note, in vitro experiments showed a very modest overlap with in vivo results. Bioinformatics prediction analysis performed on miR-34a-5p and miR-451a identified several putative targets presenting no significant association with cardiotoxicity. Anyhow, the same analyses, conducted by combining all miRNAs regulated by DOX in each heart chamber, evidenced a possible dysregulation of the adherens junctions gene network, known to be involved in the onset and progression of dilated cardiomyopathy, an established detrimental side effect of the drug. ConclusionsThis is the first work investigating miRNAs regulation by DOX both in plasma and heart districts of treated animals. Our results indicate a strong association of miR-34a-5p and miR-451a to DOX-induced cardiotoxicity. In addition, the observed altered expression of diverse miRNAs in separated cardiac chambers hints at a specific response to the drug, implying the existence of different players and pathways leading to dysfunction onset.

Co-administration of resveratrol with doxorubicin in young mice attenuates detrimental late-occurring cardiovascular changes.

Doxorubicin (DOX) is among the most effective chemotherapies used in paediatric cancer patients. However, the clinical utility of DOX is offset by its well-known cardiotoxicity, which often does not appear until later in life. Since hypertension significantly increases the risk of late-onset heart failure in childhood cancer survivors, we investigated whether juvenile DOX exposure impairs the ability to adapt to angiotensin II (Ang II)-induced hypertension later in life and tested a treatment that could prevent this. Five-week-old male mice were administered a low dose of DOX (4 mg/kg) or saline once a week for 3 weeks and then allowed to recover for 5 weeks. Following the 5-week recovery period, mice were infused with Ang II or saline for 2 weeks. In another cohort, mice were fed chow containing 0.4% resveratrol 1 week before, during, and 1 week after the DOX administrations. One week after the last DOX administration, p38 mitogen-activated protein kinase (MAPK) was activated in hearts of DOX-treated mice demonstrating molecular signs of cardiac stress; yet, there was no change in cardiac function between groups. However, DOX-treated mice failed to develop compensatory cardiac hypertrophy in response to Ang II-induced hypertension later in life. Of importance, mice receiving DOX with resveratrol co-administration displayed normalization in p38 MAPK activation in the heart and a restored capacity for cardiac hypertrophy in response to Ang II-induced hypertension. We have developed a juvenile mouse model of DOX-induced cardiotoxicity that displays no immediate overt physiological dysfunction; but, leads to an impaired ability of the heart to adapt to hypertension later in life. We also show that co-administration of resveratrol during DOX treatment was sufficient to normalize molecular markers of cardiotoxicity and restore the ability of the heart to undergo adaptive remodelling in response to hypertension later in life.

Resveratrol suppresses doxorubicin-induced cardiotoxicity by disrupting E2F1 mediated autophagy inhibition and apoptosis promotion

The clinical use of doxorubicin (DOX) is limited by cardiotoxicity, involving the dysregulation of autophagy and apoptosis in the myocardium, which were partly reversed by resveratrol (RSV) supplement. However, a definitive mechanisms accounting for DOX’s cardiotoxicity and the protective role of RSV remain poorly defined. The aim of the present study was to clarify the specific role of E2F transcription factor 1 (E2F1) in regulating autophagy and apoptosis in DOX-induced cardiotoxicity as well as the protective effects of RSV. Autophagy and apoptosis were successfully induced by the serum deprivation strategy in H9c2 cardiomyocytes. DOX inhibited autophagy through activating E2F1/mammalian target of rapamycin complex 1 (mTORC1) pathway and further induced apoptosis by activating E2F1/AMP-activated protein kinase α2 (AMPKα2) pathway in starved H9C2 cells. And RSV supplement showed increased autophagy and decreased apoptosis, accompanied with inhibitory effect on E2F1/mTORC1 as well as E2F1/AMPKα2 pathway. Moreover, the favorable effect of RSV on autophagy and apoptosis was dependent on E2F1. The same result was observed in the mouse model of DOX-induced cardiotoxicity in both non-myocardial ischemia and myocardial ischemia condition. Injection with DOX and RSV in combination, resulted in a reduced apoptotic ratio and activated autophagy process compared with the DOX treatment alone. In conclusions, RSV, which has been suggested to attenuate DOX-induced cytotoxicity, significantly blocks induction of E2F1/mTORC1 and E2F1/AMPKα2 pathway by DOX, leading to acceleratory autophagy and inhibitory apoptosis. And E2F1 plays a key role for the protective effect of RSV.

Hydrogen sulfide protects H9c2 cardiac cells against doxorubicin-induced cytotoxicity through the PI3K/Akt/FoxO3a pathway

Doxorubicin(DOX) is an efficient drug used in cancer therapy that also produces reactive oxygen species(ROS) that induces severe cytotoxicity, which limits its clinical application. Hydrogen sulfide(H2S), a novel gasotransmitter, has been shown to exert cardioprotective effects. The present study aimed to determine whether exogenous H2S protects H9c2 cardiac cells against DOX-induced cytotoxicity and whether these protective effects are mediated through the PI3K/Akt/FoxO3a pathway. The H9c2 cardiac cells were exposed to 5µM DOX for 24h to establish a model of DOX-induced cardiotoxicity. The results showed that the treatment of H9c2 cardiac cells with sodium hydrosulfide(NaHS) for 30min prior to DOX exposure markedly attenuated the phosphorylation of Akt and FoxO3a. Notably, pre-treatment of the H9c2 cells with NaHS significantly attenuated the nuclear localization of FoxO3a as well as the apoptosis of H9c2 cells induced by DOX. The treatment of H9c2 cells with N-acetyl-L-cysteine(NAC), a scavenger of ROS, prior to DOX exposure, also markedly increased the phosphorylation of Akt and FoxO3a which was inhibited by DOX alone. Furthermore, pre-treatment with LY294002, a selective inhibitor of PI3K/Akt, reversed the protective effect of H2S against DOX-induced injury of cardiomyocytes, as demonstrated by an increased number of apoptotic cells, a decrease in cell viability and the reduced phosphorylation of Akt and FoxO3a. These findings suggested that exogenous H2S attenuates DOX-induced cytotoxic effects in H9c2 cardiac cells through the PI3K/Akt/FoxO3a pathway.

Resveratrol-induced autophagy promotes survival and attenuates doxorubicin-induced cardiotoxicity

Resveratrol (RSV) has many biological effects, including antitumor and antiviral activities, and vascular protection. Recent studies have suggested that RSV exerts its antitumor effects through induction of autophagy by an unknown mechanism. Doxorubicin (DOX) is a wide spectrum antitumor drug, but its clinical application is limited by its cardiotoxicity. This study evaluated whether the manipulation of autophagy could attenuate the cardiotoxic effects of DOX in vitro as well as in a rat model of DOX-induced cardiotoxicity. We found that DOX induced H9C2 cell apoptosis by inhibiting AMPK activation and promoting pro-apoptotic protein expression through p38MAPK/p53 signaling. RSV-treated H9C2 cells showed increased autophagy through the AMPK/mTOR/Ulk1 pathway. When DOX and RSV were combined, apoptosis was decreased, despite a slight increase in the autophagy ratio. The same result was observed in the rat model of DOX-induced cardiotoxicity. Injection with DOX or RSV alone, or in combination, for a week, resulted in a reduced apoptotic ratio in the combination group compared with the DOX alone group. Our results strongly indicate that this co-treatment strategy with RSV can attenuate the cardiotoxic effects of DOX. Our findings may have important clinical implications.

Resveratrol protects cardiomyocytes from doxorubicin-induced apoptosis through the AMPK/P53 pathway.

Doxorubicin (DOX) is an efficient drug used in cancer therapy; however, it has severe cardiotoxic side effects. The aim of the present study was to investigate the effects of resveratrol on the adenosine monophosphate-activated protein kinase (AMPK)/P53 pathway in mediating DOX-induced cytotoxicity. H9c2 cells were exposed to 5 µM DOX for 24 h to establish a model of DOX-induced cardiotoxicity. DOX administration amplified P53 and B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax) expression and decreased Bcl-2 expression in H9c2 cells. Resveratrol increased the cell viability and decreased the apoptotic rate. In addition, resveratrol markedly increased the phosphorylation of AMPK. Of note, resveratrol protected against DOX-induced increases of P53 and Bax and also prevented the downregulation of Bcl-2 in H9c2 cells. Furthermore, AMPK inhibitor Compound C abolished the protective effects of resveratrol. The results of the present study therefore indicated that resveratrol protected H9c2 cells from DOX-induced apoptosis via the AMPK/P53 pathway.

Metformin rescues the myocardium from doxorubicin-induced energy starvation and mitochondrial damage in rats.

Clinical use of doxorubicin (DOX) is limited by its cardiotoxic side effects. Recent studies established that metformin (MET), an oral antidiabetic drug, possesses an antioxidant activity. However, whether it can protect against DOX-induced energy starvation and mitochondrial damage has not been reported. Our results, in a rat model of DOX-induced cardiotoxicity, show that DOX treatment significantly increased serum levels of LDH and CK-MB, indicators of cardiac injury, and induced expression of hypertrophic gene markers. DOX also caused marked decreases in the cardiac levels of glutathione, CoA-SH and ATP, and mRNA expression of catalase and NQO-1. These biochemical changes were associated with myocardial histopathological and ultrastructural deteriorations, as observed by light and electron microscopy, respectively. Cotreatment with MET (500 mg/kg) eliminated all DOX-induced biochemical, histopathological, and ultrastructural changes. These findings demonstrate that MET successfully prevents DOX-induced cardiotoxicity in vivo by inhibiting DOX-induced oxidative stress, energy starvation, and depletion of intramitochondrial CoA-SH.

Protective effect of tetrahydroxystilbene glucoside on cardiotoxicity induced by doxorubicin in vitro and in vivo

To test the effect of 2,3,5,4'-tetrahydroxystilbene-2-O-beta-D-glucoside (THSG) on doxorubicin (DOX)-induced cardiotoxicity. We used neonate rat cardiomyocytes and an acute mouse model of DOX-induced cardiotoxicity to examine the protective effect of THSG. In the mouse model, administration of THSG significantly reduced DOX-induced cardiotoxicity, including animal mortality, histopathological changes, and levels of serum creatine kinase (CK) and lactate dehydrogenase (LDH). Moreover, THSG was able to attenuate the increased malondialdehyde (MDA) and decreased reduced glutathione (GSH) caused by DOX. In in vitro studies, THSG 10-300 micromol/L ameliorated DOX-induced cardiomyocyte apoptosis in a concentration-dependent manner. Further studies showed that THSG inhibited reactive oxygen species (ROS) generation and prevented DOX-induced loss of mitochondrial membrane potential, caspase-3 activation and upregulation of Bax protein expression. We observed a protective response against damage after DOX treatment. The level of Bcl-2 protein was increased. Additionally, THSG inhibited a DOX-induced [Ca(2+)] increase. These results showed that THSG protected against DOX-induced cardiotoxicity by decreasing ROS generation and intracellular [Ca(2+)] and by inhibiting apoptotic signaling pathways.

ARC is a critical cardiomyocyte survival switch in doxorubicin cardiotoxicity

Despite its complexity of action, doxorubicin (Dox)-induced cardiomyopathy eventually results in loss of cardiac myocytes which further contributes to the development of overt heart failure. In the present study, we examined the relevance of the apoptosis repressor with caspase recruitment domain (ARC) on cardiac myocyte survival and its underlying mechanisms in a model of Dox-induced cardiotoxicity. Exposure of neonatal rat ventricular cardiomyocytes with Dox resulted in a downregulation of ARC mRNA and protein levels that occurred in a pre-translational and post-translational manner and led to a significant induction of apoptosis. Proteasomal inhibitors partially rescued both Dox-induced downregulation of ARC protein and induction of apoptosis. Knockdown of endogenous ARC sensitised cardiomyocytes to undergo apoptosis upon treatment with Dox. In contrast, enforced expression of ARC by adenoviral-mediated gene transfer dramatically increased the resistance of cardiomyocytes to undergo apoptotic cell death following Dox administration. In response to Dox, Bax translocated from cytosol to mitochondria where it resulted in dissipation of the mitochondrial membrane potential, cytochrome c release and activation of caspases -3 and -9. ARC prevented Bax translocation to the mitochondrium and thereby blocked the activation of the mitochondrial apoptotic death pathway in a t-Bid and caspase-8-independent manner. In this study, we provide evidence for the protective role of anti-apoptotic ARC in Dox-induced cardiotoxicity, which makes this molecule an interesting target for future therapies.

Potent Metalloporphyrin Peroxynitrite Decomposition Catalyst Protects Against the Development of Doxorubicin-Induced Cardiac Dysfunction

Increased oxidative stress and dysregulation of nitric oxide have been implicated in the cardiotoxicity of doxorubicin (DOX), a commonly used antitumor agent. Peroxynitrite is a reactive oxidant produced from nitric oxide and superoxide in various forms of cardiac injury. Using a novel metalloporphyrinic peroxynitrite decomposition catalyst, FP15, and nitric oxide synthase inhibitors or knockout mice, we now delineate the pathogenetic role of peroxynitrite in rodent models of DOX-induced cardiac dysfunction. Mice received a single injection of DOX (25 mg/kg IP). Five days after DOX administration, left ventricular performance was significantly depressed, and high mortality was noted. Treatment with FP15 and an inducible nitric oxide synthase inhibitor, aminoguanidine, reduced DOX-induced mortality and improved cardiac function. Genetic deletion of the inducible nitric oxide synthase gene was also accompanied by better preservation of cardiac performance. In contrast, inhibition of the endothelial isoform of nitric oxide synthase with N-nitro-L-arginine methyl ester increased DOX-induced mortality. FP15 reduced the DOX-induced increase in serum LDH and creatine kinase activities. Furthermore, FP15 prevented the DOX-induced increase in lipid peroxidation, nitrotyrosine formation, and metalloproteinase activation in the heart but not NAD(P)H-driven superoxide generation. Peroxynitrite neutralization did not interfere with the antitumor effect of DOX. FP15 also decreased ischemic injury in rats and improved cardiac function and survival of mice in a chronic model of DOX-induced cardiotoxicity. Thus, peroxynitrite plays a key role in the pathogenesis of DOX-induced cardiac failure. Targeting peroxynitrite formation may represent a new cardioprotective strategy after DOX exposure or in other conditions associated with peroxynitrite formation, including myocardial ischemia/reperfusion injury.