Doxorubicin-induced Cardiomyopathy In Mice Research Articles

Metal-Free CO Prodrugs Activated by Molecular Oxygen Protect against Doxorubicin-Induced Cardiomyopathy in Mice.

Carbon monoxide has been extensively studied for its various therapeutic activities in cell cultures and animal models. Great efforts have been made to develop noninhalational approaches for easy and controlled CO delivery. Herein, we introduce a novel metal-free CO prodrug approach that releases CO under near-physiological conditions. CO from the quinone-derived CO prodrugs is initiated by general acid/base-catalyzed tautomerization followed by oxidation by molecular oxygen to form the key norbornadienone intermediate, leading to cheletropic CO release only in an aerobic environment. Representative CO prodrug analog QCO-105 showed marked anti-inflammatory effects and HO-1 induction activity in RAW264.7 macrophages. In a mouse model of doxorubicin-induced cardiomyopathy, we show for the first time that the CO prodrug QCO-105 prevented cardiomyocyte injury, consistent with the known organ-protective effects of HO-1 and CO. Overall, such a new CO prodrug design serves as the starting point for developing CO-based therapy in attenuating the cardiotoxicity of doxorubicin.

Poly (ADP-ribose) polymerase pathway inhibitor (Olaparib) upregulates SERCA2a expression and attenuates doxorubicin-induced cardiomyopathy in mice

The cardiotoxicity induced by doxorubicin is dose-dependent. The present study tested the potential cardioprotective effect of Poly ADP Ribose Polymerase (PARP) pathway inhibitor “olaparib” in a mouse model of doxorubicin-induced cardiomyopathy (DOX-CM). Seventy-two male BALB/c mice were randomized into six equal groups; control, DOX-CM, dexrazoxane-treated, and three olaparib-treated groups (5, 10, and 50 mg/kg/day). Cardiomyopathy was assessed by heart weight/Tibial length (HW/TL) ratio, cardiac fibrosis, oxidative stress, and electron microscope. Myocardial expression of SERCA2a mRNA and cleaved PARP-1 protein were also assessed. Similar to dexrazoxane, olaparib (10 mg/kg/day) significantly ameliorated oxidative stress, and preserved cardiac structure. It also suppressed myocardial PARP-1 protein expression and boosted SERCA2a mRNA expression. Olaparib (5 or 50 mg/kg/day) failed to show comparable effects. The current study detected the cardioprotective effect of olaparib at a dosage of 10 mg/kg/day. Also, the present study discovered a new cardioprotective mechanism of dexrazoxane by targeting PARP-1 in the heart.

Nigella sativa oil alleviates doxorubicin-induced cardiomyopathy and neurobehavioral changes in mice

Objective: To investigate the effect of Nigella sativa oil on cardiomyopathy and neurobehavioral changes induced by doxorubicin in mice. Methods: Swiss strain of albino female mice were divided into 6 groups of 5 animals in each: Group I (control group), group II (doxorubicin, 10 mg/kg, i.v.), group III, IV, and V (Nigella sativa oil; 1.5, 3, and 6 mL/kg, respectively), group Ή (Nigella sativa oil per se; 6 mL/kg, p.o.). The duration of treatment was 15 d (10 days’ pre-treatment and 5 days’ post-treatment) and doxorubicin was administered on day 11th of the treatment schedule. Following Nigella sativa oil treatment, neurobehavioral tests, cardiac hypertrophy tests, and biochemical tests in serum and tissues were performed. Neurological tests included assessment of anxiety-like behavior in the elevated plus maze, spontaneous alternation behavior in the cross maze, and depression-like behavior in modified forced swim tests. Biochemical tests included serum lactate dehydrogenase and creatinine kinase-MB, malondialdehyde and reduced glutathione in tissues. Lastly, molecular docking was used to estimate the affinity of the phytoconstituents of Nigella sativa oil with histone deacetylases. Results: Nigella sativa oil treatment significantly (P<0.001) restored doxorubicin-induced neurobehavioral changes, decreased lactate dehydrogenase and creatinine kinase-MB in the plasma, malondialdehyde contents in tissues, and increased reduced glutathione level. Besides, no significant alteration was observed in Nigella sativa oil per se group as compared to the control. Molecular docking showed that Nigella sativa oil components had appreciable binding affinitiy with the protein cavities of HDAC1 and HDAC6. Conclusions: The result shows that Nigella sativa oil exerts anxiolytic, antidepressant, and memory-enhancing effects in addition to cardioprotective effect against doxorubicin-induced cardiomyopathy in mice. The modulatory effect of Nigella sativa oil on oxidative stress could contribute to the cardioprotective effect and associated neurobehavioral changes in mice.

LCN2 deficiency ameliorates doxorubicin-induced cardiomyopathy in mice

Doxorubicin (DOX) is an effective anticancer drug with the side effect of irreparable cardiomyopathy. Lipocalin-2 (LCN2) has been identified as an important regulator of oxidative stress and inflammation in cardiovascular disease pathophysiology. Here, we demonstrate that LCN2 deletion increases autophagic flux in the DOX-treated hearts. Mice were injected intraperitoneally six times with 30 mg/kg DOX. Echocardiography showed that DOX-treated wild-type (WT) mice had markedly weaker cardiac function compared to saline-treated WT mice. In DOX-treated LCN2 knockout (KO) mice, cardiac function was partially restored. Histological analysis showed a reduction in cardiomyocyte diameter in DOX-treated WT mice that was ameliorated in DOX-treated LCN2KO mice. Cardiac levels of phosphorylated signal transducer and activator of transcription 3, LCN2, heme oxygenase-1, and NAD (P) H dehydrogenase were markedly greater in DOX-treated WT mice than in DOX-treated LCN2KO mice. Light chain 3B (LC3B)II expression was higher in DOX-treated WT mice, but lower in DOX-treated LCN2KO mice when compared to saline-treated WT mice. Less co-localization of LC3B and lysosomal-associated membrane protein 1 was observed in DOX-treated WT mice than in DOX-treated LCN2KO mice. LCN2 co-localized with LC3B-stained cells in the DOX-treated WT mouse heart, but not in the DOX-treated LCN2KO mouse heart. These findings indicate that the cardiotoxic effect of DOX is due to autophagosome accumulation mediated by LCN2 upregulation and that LCN2 may inhibit autophagic flux, leading to DOX-induced cardiomyopathy.

Cardioprotective effects of dantrolene in doxorubicin-induced cardiomyopathy in mice.

BackgroundDoxorubicin (Dox) is a potent chemotherapeutic agent, but its usage is limited by dose-dependent cardiotoxicity. Intracellular calcium dysregulation has been reported to be involved in doxorubicin-induced cardiomyopathy (DICM). The cardioprotective role of RyR stabilizer dantrolene (Dan) on the calcium dynamics of DICM has not yet been explored.ObjectiveTo evaluate the effects of dantrolene on intracellular calcium dysregulation and cardiac contractile function in a DICM model.MethodsAdult male C57BL/6 mice were randomized into 4 groups: (1) Control, (2) Dox Only, (3) Dan Only, and (4) Dan + Dox. Fractional shortening (FS) and left ventricular ejection fraction (LVEF) were assessed by echocardiography. In addition, mice were sacrificed 2 weeks after doxorubicin injection for optical mapping of the heart in a Langendorff setup.ResultsTreatment with Dox was associated with a reduction in both FS and LVEF at 2 weeks (P < .0001) and 4 weeks (P < .006). Dox treatment was also associated with prolongation of calcium transient durations CaTD50 (P = .0005) and CaTD80 (P < .0001) and reduction of calcium amplitude alternans ratio (P < .0001). Concomitant treatment with Dan prevented the Dox-induced decline in FS and LVEF (P < .002 at both 2 and 4 weeks). Dan also prevented Dox-induced prolongation of CaTD50 and CaTD80 and improved the CaT alternans ratio (P < .0001). Finally, calcium transient rise time was increased in the doxorubicin-treated group, indicating RyR2 dyssynchrony, and dantrolene prevented this prolongation (P = .02).ConclusionDantrolene prevents cardiac contractile dysfunction following doxorubicin treatment by mitigating dysregulation of calcium dynamics.

Ameliorative Effect of Trehalose on Liver Due to Doxorubicin-Induced Cardiomyopathy in Mice

Doxorubicin (DOX) is one of the most efficient anticancer chemotherapeutic drugs. However, its use is limited due to the induction of irreversible dilated cardiomyopathy and hepatotoxicity. The present study aimed to evaluate the hepatoprotective effect of trehalose (TRE) against DOX –induced cardiomyopathy(DIC). Mice were divided into five treated groups: Control group given saline, DOX group (2mg/kg body weight three times per week for three weeks day after day), TRE group (200µg/mouse three times per week for three weeks day after day), DOX+TRE cotreatment group (animals were co-administered 2mg/kg body weight of DOX with 200µg/mouse TRE by the same time), and DOX+TRE post treatment group (animals received 2mg/kg body weight DOX followed by treatment with 200µg/mouse TRE after 18 days). The obtained results indicated that DOX-treatment resulted in a decrease in body and liver weight ,and relative weight of liver compared to the control group. In addition, DOX-treatment caused an increase in activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST),and in level of hepatic malondialdehyde (MDA) concentration. However, concentration of total thiols (T-thiol), total antioxidant capacity (TAC) as well as catalase (CAT) enzyme activity were reduced in DOX-treated mice. Furthermore, dramatic changes in the histological architecture of the liver were observed. On the other hand, an improvement in the activities of ALT,AST, and CAT as well as levels of hepatic MDA ,T-thiol and TAC were observed in animals administrated with TRE either alone or in combination with DOX in cotreatment and post treatment groups in comparison with the ones treated with DOX alone. Moreover, histopathological examination of liver tissues in mice co-treated with DOX and TRE showed a significant improvement in hepatic parenchyma as compared to mice treated with DOX alone.

2-Aminobutyric acid modulates glutathione homeostasis in the myocardium.

A previous report showed that the consumption of glutathione through oxidative stress activates the glutathione synthetic pathway, which is accompanied by production of ophthalmic acid from 2-aminobutyric acid (2-AB). We conducted a comprehensive quantification of serum metabolites using gas chromatography-mass spectrometry in patients with atrial septal defect to find clues for understanding myocardial metabolic regulation, and demonstrated that circulating 2-AB levels reflect hemodynamic changes. However, the metabolism and pathophysiological role of 2-AB remains unclear. We revealed that 2-AB is generated by an amino group transfer reaction to 2-oxobutyric acid, a byproduct of cysteine biosynthesis from cystathionine. Because cysteine is a rate-limiting substrate for glutathione synthesis, we hypothesized that 2-AB reflects glutathione compensation against oxidative stress. A murine cardiomyopathy model induced by doxorubicin supported our hypothesis, i.e., increased reactive oxygen species are accompanied by 2-AB accumulation and compensatory maintenance of myocardial glutathione levels. Intriguingly, we also found that 2-AB increases intracellular glutathione levels by activating AMPK and exerts protective effects against oxidative stress. Finally, we demonstrated that oral administration of 2-AB efficiently raises both circulating and myocardial glutathione levels and protects against doxorubicin-induced cardiomyopathy in mice. This is the first study to demonstrate that 2-AB modulates glutathione homeostasis in the myocardium.

Matricellular protein CCN1 mediates doxorubicin-induced cardiomyopathy in mice

Doxorubicin (DOX) is an effective chemotherapeutic agent however its clinical use is limited by its cumulative cardiotoxicity. Matricellular protein CCN1 mediates work-overload-induced cardiac injury. We aimed to assess the role of CCN1 in DOX-associated cardiomyopathy. Here we discovered CCN1 expression in the myocardium 1 day after DOX treatment (15 mg/kg; i.p.) in mice. Whereas CCN1 synergizes with Fas ligand (FasL) to induce cardiomyocyte apoptosis, we found that FasL was also induced by DOX in the heart. To assess the function of CCN1 in vivo, knockin mice (Ccn1dm/dm) expressing an β6β1-binding defective CCN1 mutant were treated with a single dose of DOX (15 mg/kg; i.p.). Compared with wild-type mice, Ccn1dm/dm mice were resistant to DOX-induced cardiac injury and dysfunction 14 days after injection. Using rat cardiomyoblast H9c2 cells, we demonstrated that DOX induced reactive oxygen species accumulation to upregulate CCN1 and FasL expression. CCN1 mediated DOX cardiotoxicity by engaging integrin β6β1 to promote p38 mitogen-activated protein kinase activation and the release of mitochondrial Smac and HtrA2 to cytosol, thereby counteracting the inhibition of XIAP and facilitating apoptosis. In summary, CCN1 critically mediates DOX-induced cardiotoxicity. Disrupting CCN1/β6β1 engagement abolishes DOX-associated cardiomyopathy in mice.

Sirt3 protects mitochondrial DNA damage and blocks the development of doxorubicin-induced cardiomyopathy in mice

Doxorubicin (Doxo) is a chemotherapeutic drug widely used to treat variety of cancers. One of the most serious side effects of Doxo is its dose-dependent and delayed toxicity to the heart. Doxo is known to induce cardiac mitochondrial damage. Recently, the mitochondrial sirtuin SIRT3 has been shown to protect mitochondria from oxidative stress. Here we show that overexpression of SIRT3 protects the heart from toxicity of Doxo by preventing the drug-induced mitochondrial DNA (mtDNA) damage. Doxo treatment caused depletion of Sirt3 levels both in primary cultures of cardiomyocytes and in mouse hearts, which led to massive acetylation of mitochondrial proteins. Doxo-induced toxicity to cardiomyocytes was associated with increased reactive oxygen species (ROS) production, mitochondrial fragmentation, and cell death. Overexpression of SIRT3 helped to attenuate Doxo-induced ROS levels and cardiomyocyte death. Sirt3 knockout (Sirt3.KO) mice could not endure the full dose of Doxo treatment, developed exacerbated cardiac hypertrophy, and died during the course of treatment, whereas Sirt3 transgenic (Sirt3.tg) mice were protected against Doxo-induced cardiotoxicity. Along with Sirt3, we also observed a concomitant decrease in levels of oxoguanine-DNA glycosylase-1 (OGG1), a major DNA glycosylase that hydrolyzes oxidized-guanine (8-oxo-dG) to guanine. Depletion of OGG1 levels was associated with increased mtDNA damage. Sirt3.KO mice and Doxo-treated mice showed increased 8-oxo-dG adducts in DNA and corresponding increase in mtDNA damage, whereas, 8-oxo-dG adducts and mtDNA damage were markedly reduced in Sirt3 overexpressing transgenic mice hearts. These results thus demonstrated that Sirt3 activation protects the heart from Doxo-induced cardiotoxicity by maintaining OGG1 levels and protecting mitochondria from DNA damage.

Protective effect of cilostazol against doxorubicin-induced cardiomyopathy in mice

Doxorubicin (Dox) is an effective anti-cancer drug, but its use is limited because of its adverse effect of inducing irreversible dilated cardiomyopathy. Cilostazol (Cilo), a potent phosphodiesterase III inhibitor, has been reported to have an anti-inflammatory effect. Here, we investigated whether Cilo has a protective effect against Dox-induced cardiomyopathy (DIC). Mice were randomly divided into four groups: saline control, Dox (15mg/kg), Dox (15mg/kg) plus Cilo (50mg/kg), and Cilo (50mg/kg). The results showed that the coadministration of Dox and Cilo significantly enhanced left-ventricular systolic function compared with Dox alone. In addition, Cilo treatment significantly reduced Dox-induced perivascular fibrosis, collagen concentration, and connective growth factor expression in the heart. Also, Cilo administration markedly reduced Dox-induced levels of serum B-type natriuretic peptide, dysferlin, high-mobility group protein B1, Toll-like receptor 4, nuclear factor-κB p65, and cyclooxygenase-2. Furthermore, Cilo treatment significantly reduced Dox-induced oxidative stress by lowering the translocation of Nrf2 into the nucleus and the expression of NQO1, heme oxygenase 1, and superoxide dismutase-1. Our results suggest that Cilo may be a potential antifibrotic, antioxidative, and anti-inflammatory drug for DIC.

Arginase inhibition augments nitric oxide production and facilitates left ventricular systolic function in doxorubicin-induced cardiomyopathy in mice.

A metabolizing enzyme arginase can decrease nitric oxide (NO) production by competing with NO synthase for arginine as a substrate, but its pathophysiological role in heart failure remains unknown. We aimed to investigate the effect of pharmacological inhibition of arginase on left ventricular function in doxorubicin‐induced cardiomyopathy in mice. Doxorubicin administration for 5 weeks significantly increased protein expression levels or activity of arginase in the lungs and liver, and caused moderate increase in arginase 2 expression in the aorta. In the lungs, accumulated interstitial cells strongly expressed both arginase 1 and arginase 2 by doxorubicin administration. Echocardiography revealed that administration of a potent, reversible arginase inhibitor N‐omega‐hydroxy‐nor‐l‐arginine completely reversed doxorubicin‐induced decrease in the ejection fraction, in parallel with expression levels of BNP mRNA, without affecting apoptosis, hypertrophy, fibrosis, or macrophage infiltration in the left ventricle. Arginase inhibition reversibly lowered systolic blood pressure, and importantly, it recovered doxorubicin‐induced decline in NO concentration in the serum, lungs, and aorta. Furthermore, arginase inhibition stimulated NO secretion from aortic endothelial cells and peritoneal macrophages in vitro. In conclusion, pharmacological inhibition of arginase augmented NO concentration in the serum, lungs, and aorta, promoted NO‐mediated decrease in afterload for left ventricle, and facilitated left ventricular systolic function in doxorubicin‐induced cardiomyopathy in mice.

S-diclofenac Protects against Doxorubicin-Induced Cardiomyopathy in Mice via Ameliorating Cardiac Gap Junction Remodeling

Hydrogen sulfide (H2S), as a novel gaseous mediator, plays important roles in mammalian cardiovascular tissues. In the present study, we investigated the cardioprotective effect of S-diclofenac (2-[(2,6-dichlorophenyl)amino] benzeneacetic acid 4-(3H-1,2,dithiol-3-thione-5-yl)phenyl ester), a novel H2S-releasing derivative of diclofenac, in a murine model of doxorubicin-induced cardiomyopathy. After a single dose injection of doxorubicin (15 mg/kg, i.p.), male C57BL/6J mice were given daily treatment of S-diclofenac (25 and 50 µmol/kg, i.p.), diclofenac (25 and 50 µmol/kg, i.p.), NaHS (50 µmol/kg, i.p.), or same volume of vehicle. The cardioprotective effect of S-diclofenac was observed after 14 days. It showed that S-diclofenac, but not diclofenac, dose-dependently inhibited the doxorubicin-induced downregulation of cardiac gap junction proteins (connexin 43 and connexin 45) and thus reversed the remodeling of gap junctions in hearts. It also dose-dependently suppressed doxorubicin-induced activation of JNK in hearts. Furthermore, S-diclofenac produced a dose-dependent anti-inflammatory and anti-oxidative effect in this model. As a result, S-diclofenac significantly attenuated doxorubicin-related cardiac injury and cardiac dysfunction, and improved the survival rate of mice with doxorubicin-induced cardiomyopathy. These effects of S-diclofenac were mimicked in large part by NaHS. Therefore, we propose that H2S released from S-diclofenac in vivo contributes to the protective effect in doxorubicin-induced cardiomyopathy. These data also provide evidence for a critical role of H2S in the pathogenesis of doxorubicin-induced cardiomyopathy.

Cardioprotective Effect of Endogenous Pituitary Adenylate Cyclase-Activating Polypeptide on Doxorubicin-Induced Cardiomyopathy in Mice

Pituitary adenylate cyclase-activating polypeptide (PACAP) is known as a cytoprotective polypeptide. PACAP and its receptors are expressed in the heart, but it is unclear whether PACAP exerts its protective effect on the myocardium in vivo. The aim of the present study was to investigate whether endogenous PACAP has a cardioprotective effect on Doxorubicin (Dox)-induced cardiomyopathy. Dox was intraperitoneally injected to induce cardiomyopathy in wild type (WT) and PACAP knockout (ie, PACAP+/- and PACAP-/-) mice. The survival rates up to 15 days of PACAP+/- mice and PACAP-/- mice were significantly less than that of WT mice. Cardiac function, measured by echocardiography, was significantly lower in PACAP+/- mice than in WT mice at day 10. Morphological examination of sections of myocardium showed degenerative change and fibrosis in PACAP+/- mice at day 10. Serum reactive oxygen metabolites (a marker of oxidative stress), the number of 8-hydroxy-deoxyguanosine-positive nuclei and TdT-mediated dUTP nick end-labeling (TUNEL) positive nuclei in the myocardium were higher in PACAP+/- mice than WT mice. However, continuous subcutaneous administration of PACAP38 was able to prevent the myocardial damage typically caused by Dox injection in PACAP+/-. These results suggest that endogenous PACAP might attenuate Dox-induced myocardial damage and that its mechanism of action is likely to be associated with the reduction of oxidative stress and mediated via anti-apoptotic effects.

Adiponectin Protects Doxorubicin-induced Cardiomyopathy in Mice

Adiponectin Protects Doxorubicin-induced Cardiomyopathy in Mice

Adiponectin Protects Doxorubicin-induced Cardiomyopathy in Mice

Adiponectin Protects Doxorubicin-induced Cardiomyopathy in Mice

Reduction of HMG-CoA-reductase leads to improved cardiac function in doxorubicin-induced cardiomyopathy in mice

Reduction of HMG-CoA-reductase leads to improved cardiac function in doxorubicin-induced cardiomyopathy in mice

Prediction and Prevention of Chemotherapy-Induced Cardiomyopathy

Although anthracyclines are highly effective at treating certain cancers, their use is limited by the potential for cardiotoxicity. Studies report a wide range of the incidence of cardiotoxicity, related to differences in definitions, chemotherapy regimens, and patient populations. The occurrence of clinical heart failure seems to be in the range of 1% to 5%, and asymptomatic decrease in left ventricular function is in the range of 5% to 20%.1,2 Toxicity can occur early (within 1 year) or late (particularly among children, where late cardiac abnormalities are detectable in two thirds of surviving patients).3 The occurrence of cardiomyopathy is related to cumulative dose of anthracycline (especially doxorubicin doses >550 mg/m2), dosing schedule, age, gender, mediastinal irradiation, and combination with other agents, including trastuzumab.4 Other chemotherapy, including imatinib mesylate,5 can also cause cardiotoxicity, suggesting a broader potential for adverse cardiac effects from novel chemotherapy and, especially, from inhibitors of nonreceptor tyrosine kinases. Anthracycline-induced cardiomyopathy seems to have a similar impact on survival as other forms of heart failure.6 Thus, identification of individuals at risk, prevention, early diagnosis, and effective treatment are all important goals. Most of these needs have been addressed by uncontrolled or small studies, and guidelines have relatively sparse information on which to base recommendations for care, other than careful monitoring of left …

Morphometric study of myocardial changes during doxorubicin-induced cardiomyopathy in mice

Doxorubicin (DOX) is one of the most effective anti-cancer drugs in oncology, but may cause a cumulative dose-dependent cardiomyopathy in a number of cancer patients. The effect of DOX on the heart was studied in mice treated with i.v. injections of 2 mg/kg by measuring morphometric parameters, including nuclear index (number of non-myocytes/number of myocyte nuclei), reticulin index (reticulin area/number of myocyte transsections), nuclear transsectional area, myocyte transsectional area, capillary index (number of capillaries/number of myocyte transsections) and capillary transsectional area. The highest significant difference between control mice and DOX-treated mice was observed immediately after the 12th dose of DOX except for the two capillary parameters. The highest level of significance for these two parameters was obtained 12 weeks after the end of DOX treatment. In contrast to the observations in rats, mice did not develop a nephrotic syndrome during treatment with DOX. The morphometric analysis of myocardial changes in mice, as a quantitative and objective method, seems to be a good model for comparative studies on cardiomyopathy induced by anthracycline analogues.