Downregulating miRNA-199a-5p exacerbates fluorouracil-induced cardiotoxicity by activating the ATF6 signaling pathway.

BACKGROUND: Fluorouracil (5-FU) might produce serious cardiac toxic reactions. miRNA-199a-5p is a miRNA primarily expressed in myocardial cells and has a protective effect on vascular endothelium. Under hypoxia stress, the expression level of miRNA-199a-5p was significantly downregulated and is closely related to cardiovascular events such as coronary heart disease, heart failure, and hypertension. We explored whether 5-FU activates the endoplasmic reticulum stress ATF6 pathway by regulating the expression of miRNA-199a-5p in cardiac toxicity. METHODS: This project established a model of primary cardiomyocytes derived from neonatal rats and treated them with 5-FU in vitro. The expression of miRNA-199a-5p and its regulation were explored in vitro and in vivo. RESULTS: 5-FU decreases the expression of miRNA-199a-5p in cardiomyocytes, activates the endoplasmic reticulum stress ATF6 pathway, and increases the expression of GRP78 and ATF6, affecting the function of cardiomyocytes, and induces cardiac toxicity. The rescue assay further confirmed that miRNA-199a-5p supplementation can reduce the cardiotoxicity caused by 5-FU, and its protective effect on cardiomyocytes depends on the downregulation of the endoplasmic reticulum ATF6 signaling pathway. CONCLUSIONS: 5-FU can down-regulate expression of miRNA-199a-5p, then activate the endoplasmic reticulum stress ATF6 pathway, increase the expression of GRP78 and ATF6, affect the function of cardiomyocytes, and induce cardiac toxicity.

Protective Effects of Amauroderma rugosum on Doxorubicin-Induced Cardiotoxicity through Suppressing Oxidative Stress, Mitochondrial Dysfunction, Apoptosis, and Activating Akt/mTOR and Nrf2/HO-1 Signaling Pathways.

Clinical outcomes for doxorubicin (Dox) are limited by its cardiotoxicity but a combination of Dox and agents with cardioprotective activities is an effective strategy to improve its therapeutic outcome. Natural products provide abundant resources to search for novel cardioprotective agents. Ganoderma lucidum (GL) is the most well-known edible mushroom within the Ganodermataceae family. It is commonly used in traditional Chinese medicine or as a healthcare product. Amauroderma rugosum (AR) is another genus of mushroom from the Ganodermataceae family, but its pharmacological activity and medicinal value have rarely been reported. In the present study, the cardioprotective effects of the AR water extract against Dox-induced cardiotoxicity were studied in vitro and in vivo. Results showed that both the AR and GL extracts could potentiate the anticancer effect of Dox. The AR extract significantly decreased the oxidative stress, mitochondrial dysfunction, and apoptosis seen in Dox-treated H9c2 rat cardiomyocytes. However, knockdown of Nrf2 by siRNA abolished the protective effects of AR in these cells. In addition, Dox upregulated the expression of proapoptotic proteins and downregulated the Akt/mTOR and Nrf2/HO-1 signaling pathways, and these effects could be reversed by the AR extract. Consistently, the AR extract significantly prolonged survival time, reversed weight loss, and reduced cardiac dysfunction in Dox-treated mice. In addition, oxidative stress and apoptosis were suppressed, while Nrf2 and HO-1 expressions were elevated in the heart tissues of Dox-treated mice after treatment with the AR extract. However, the GL extract had less cardioprotective effect against Dox in both the cell and animal models. In conclusion, the AR water extract demonstrated a remarkable cardioprotective effect against Dox-induced cardiotoxicity. One of the possible mechanisms for this effect was the upregulation of the mTOR/Akt and Nrf2/HO-1-dependent pathways, which may reduce oxidative stress, mitochondrial dysfunction, and cardiomyocyte apoptosis. These findings suggested that AR may be beneficial for the heart, especially in patients receiving Dox-based chemotherapy.

Investigation of the mechanism of the reduction of anthracycline-induced cardiotoxicity by Qishen Huanwu Capsule based on network pharmacology.

BACKGROUND: Cancer patients who receive anthracycline-based chemotherapy regimens often discontinue chemotherapy due to cardiotoxicity. Preventing and reducing anthracycline-induced cardiotoxicity (ACT) is a hot topic in cardio-oncology research. Network pharmacology is a new discipline that integrates pharmacology, bioinformatics, and systems biology. It can be used to analyze the mechanism of action of drugs in the body from a holistic perspective by constructing a "disease-gene-drug" network, providing a new method to explore compounding mechanisms of Chinese medicine. Based on network pharmacology, this study explored the mechanism of the reduction of cardiotoxicity of anthracyclines by Qishen Huanwu Capsule. METHODS: The active ingredients of Qishen Huanwu Capsule and their targets were screened based on the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform and Chemistry Database. The target genes of ACT were screened through the PharmGkb, GeneCards, Online Mendelian Inheritance in Man (OMIM), Genetic Association Database (GAD), and Therapeutic Target Database (TTD). The Venny2.1 online analysis tool was used to construct a Venn diagram to obtain the common targets of ACT and Qishen Huanwu Capsule. The STRING platform was used to construct the protein-protein interactions (PPI) among the common targets; ClueGO software was used to perform Gene Ontology (GO) biological process enrichment analysis for the common targets; the R language was used to perform Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis; and the results were visualized using Cytoscape software. RESULTS: The predictions indicate that Qishen Huanwu Capsule has 35 main active ingredients capable of reducing the cardiotoxicity of anthracyclines and that there are 36 common targets of ACT and Qishen Huanwu Capsule that are enriched in 133 biological processes and 27 signaling pathways. CONCLUSIONS: Qishen Huanwu Capsule regulates phosphatidylinositol 3­kinase/protein kinase B (PI3K/Akt), mitogen-activated protein kinase (MAPK), forkhead box class O (FoxO) and other signaling pathways by regulating targets such as RAC-alpha serine/threonine protein kinase (Akt1), mitogen-activated protein kinase 1 (MAPK1), and mitogen-activated protein kinase 8 (MAPK8) and thereby inhibits oxidative stress and regulates apoptosis and autophagy to reduce the cardiotoxicity of anthracyclines.

Protective Effect of Methylxanthine Fractions Isolated from Bancha Tea Leaves against Doxorubicin-Induced Cardio- and Nephrotoxicities in Rats.

Doxorubicin is an anthracycline antibiotic that is used for the treatment of various types of cancer. However, its clinical usage is limited due to its potential life-threatening adverse effects, such as cardio- and nephrotoxicities. Nonetheless, simultaneous administration of doxorubicin and antioxidants, such as those found in green tea leaves, could reduce cardiac and renal tissue damage caused by oxidative stress. The methylxanthine fraction isolated from Bancha tea leaves were tested in vitro for its antioxidant activity and in vivo for its organoprotective properties against doxorubicin-induced cardio- and nephrotoxicities in a rat model. The in vivo study was conducted on male Wistar rats divided into 6 groups. Methylxanthines were administered at high (5 mg/kg body weight) and low (1 mg/kg body weight) doses, while doxorubicin was administered at a cumulative dose of 20 mg/kg body weight. Serum creatinine, uric acid, and urea concentrations, as well as serum enzyme levels (creatinine kinase (CK), creatinine kinase MB fraction (CK-MB), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH)) and electrolytes (Na+, K+, and Cl-), were analysed. In addition, histological analysis was performed to assess cardiac and renal tissue damage. The concomitant administration of Bancha methylxanthines and doxorubicin showed a dose-dependent reduction in the serum biochemical parameters, indicating a decrease in the cardiac and renal tissue damage caused by the antibiotic. Histological analysis showed that pretreatment with methylxanthines at the dose of 5 mg/kg resulted in an almost normal myocardial structure and a significant decrease in the morphological kidney changes caused by doxorubicin exposure compared with the group that received doxorubicin alone. The putative mechanism is most likely related to a reduction in the oxidative stress caused by doxorubicin.

Genetic Variability of Antioxidative Mechanisms and Cardiotoxicity after Adjuvant Radiotherapy in HER2-Positive Breast Cancer Patients.

BACKGROUND: Breast cancer treatment is associated with the occurrence of various cardiac adverse events. One of the mechanisms associated with cardiotoxicity is oxidative stress, against which cells are protected by antioxidative enzymes. Genetic variability of antioxidative enzymes can affect enzyme activity or expression, which modifies the ability of cells to defend themselves against oxidative stress and could consequently contribute to the occurrence of treatment-related cardiotoxicity. Our aim was to evaluate the association of common polymorphisms in antioxidative genes with cardiotoxicity after adjuvant radiotherapy (RT) in HER2-positive breast cancer patients. METHODS: Our retrospective study included 101 HER2-positive early breast cancer patients who received trastuzumab and adjuvant RT. We isolated DNA from buccal swabs and used competitive allele-specific PCR for genotyping of PON1 rs854560 and rs662, GSTP1 rs1138272 and rs1695, SOD2 rs4880, CAT rs1001179, and HIF1 rs1154965 polymorphisms. N-terminal pro B-type natriuretic peptide (NT-proBNP), left ventricular ejection fraction, and NYHA class were used as markers of cardiotoxicity. We used logistic regression to evaluate the association of genetic factors with markers of cardiotoxicity. RESULTS: Carriers of at least one polymorphic PON1 rs854560 allele were less likely to have increased NT-proBNP (OR = 0.34; 95% CI = 0.15-0.79; P = 0.012), even after adjustment for age (OR = 0.35; 95% CI = 0.15-0.83; P = 0.017). Carriers of at least one polymorphic PON1 rs662 allele were more likely to have increased NT-proBNP (OR = 4.44; 95% CI = 1.85-10.66; P = 0.001), even after adjustment for age (OR = 5.41; 95% CI = 2.12-13.78; P < 0.001). GSTP1 rs1695 was also associated with decreased NT-proBNP in the multivariable analysis (P = 0.026), while CAT rs1001179 was associated with NYHA class in the univariable (P = 0.012) and multivariable analysis (P = 0.023). CONCLUSION: In our study, polymorphisms PON1 rs662 and rs854560, CAT rs1001179, and GSTP1 rs1695 were significantly associated with the occurrence of cardiac adverse events after adjuvant RT and could serve as biomarkers contributing to treatment personalization.

Protective effect of Shenmai injection on doxorubicin-induced cardiotoxicity via regulation of inflammatory mediators.

BACKGROUND: Doxorubicin (DOX) is a chemotherapy drug for malignant tumors. The clinical application of DOX is limited due to its dosage relative cardiotoxicity. Oxidative damage and cardiac inflammation appear to be involved in DOX-related cardiotoxicity. Shenmai injection (SMI), which mainly consists of Panax ginsengC.A.Mey.and Ophiopogon japonicus (Thunb.) Ker Gawl, is widely used for the treatment of atherosclerotic coronary heart disease and viral myocarditis in China. In this study, we investigated the protective effect of Shenmai injection on doxorubicin-induced acute cardiac injury via the regulation of inflammatory mediators. METHODS: Male ICR mice were randomly divided into seven groups: control, DOX (10 mg/kg), SMI (5 g/kg), DOX with pretreatment with SMI (0.5 g/kg, 1.5 g/kg or 5 g/kg) and DOX with post-treatment with SMI (5 g/kg). Forty-eight hours after the last DOX administration, all mice were anesthetized for ultrasound echocardiography. Then, serum was collected for biochemical and inflammatory cytokine detection, and heart tissue was collected for histological and Western blot detection. RESULTS: A cumulative dose of DOX (10 mg/kg) induced acute cardiotoxicity in mice manifested by altered echocardiographic outcome, and increased tumor necrosis factor, interleukin 6 (IL-6), monocyte chemotactic protein 1, interferon-γ, and serum AST and LDH levels, as well as cardiac cytoplasmic vacuolation and myofibrillar disarrangement. DOX also caused the increase in the expression of IKK-α and iNOS and produced a large amount of NO, resulting in the accumulation of nitrotyrosine in the heart tissue. Pretreatment with SMI elicited a dose-dependent cardioprotective effect in DOX-dosed mice as evidenced by the normalization of serum inflammatory mediators, as well as improve dcardiac function and myofibril disarrangement. CONCLUSIONS: SMI could recover inflammatory cytokine levels and suppress the expression of IKK-α and iNOS in vivo, which was increased by DOX. Overall, there was evidence that SMI could ameliorate DOX-induced cardiotoxicity by inhibiting inflammation and recovering heart dysfunction.

Use of Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes in Preclinical Cancer Drug Cardiotoxicity Testing: A Scientific Statement From the American Heart Association.

It is now well recognized that many lifesaving oncology drugs may adversely affect the heart and cardiovascular system, including causing irreversible cardiac injury that can result in reduced quality of life. These effects, which may manifest in the short term or long term, are mechanistically not well understood. Research is hampered by the reliance on whole-animal models of cardiotoxicity that may fail to reflect the fundamental biology or cardiotoxic responses of the human myocardium. The emergence of human induced pluripotent stem cell-derived cardiomyocytes as an in vitro research tool holds great promise for understanding drug-induced cardiotoxicity of oncological drugs that may manifest as contractile and electrophysiological dysfunction, as well as structural abnormalities, making it possible to deliver novel drugs free from cardiac liabilities and guide personalized therapy. This article briefly reviews the challenges of cardio-oncology, the strengths and limitations of using human induced pluripotent stem cell-derived cardiomyocytes to represent clinical findings in the nonclinical research space, and future directions for their further use.

MicroRNA expression, targeting, release dynamics and early-warning biomarkers in acute cardiotoxicity induced by triptolide in rats.

Tripterygium wilfordii Hook. F. is a plant used in traditional Chinese medicine to treat rheumatoid arthritis, lupus erythematosus, and psoriasis in China. However, its main active substance, triptolide, has toxic effects on the heart, liver, and kidneys, which limit its clinical application. Therefore, determining the mechanism of cardiotoxicity in triptolide and identifying effective early-warning biomarkers is beneficial for preventing irreversible myocardial injury. We observed changes in microRNAs and aryl hydrocarbon receptor (AhR) as potential biomarkers in triptolide-induced acute cardiotoxicity by using techniques such as polymerase chain reaction (PCR) assay. The results revealed that triptolide increased the heart/body ratio and caused myocardial fiber breakage, cardiomyocyte hypertrophy, increased cell gaps, and nuclear dissolution in treated male rats. Real-time PCR array detection revealed a more than 2-fold increase in the expression of 108 microRNA genes in the hearts of the male rats; this not only regulated the signaling pathways of ErbB, FOXO, AMPK, Hippo, HIF-1α, mTOR, and PI3K-Akt but also participated in biological processes such as cell adhesion, cell cycling, action potential, locomotory behavior, apoptosis, and DNA binding. Moreover, triptolide reduced the circulatory and cardiac levels of AhR protein as a target of these microRNAs and the messenger RNA expression of its downstream gene CYP1 A1. However, decreases in myocardial lactate dehydrogenase, creatine kinase MB, catalase, and glutathione peroxidase activity and an increase in circulating cardiac troponin I were observed only in male rats. Moreover, plasma microRNAs exhibited dynamic change. These results revealed that circulating microRNAs and AhR protein are potentially early-warning biomarkers for triptolide-induced cardiotoxicity.

Cardiotoxicity and myocardial infarction-associated DNA damage induced by thiamethoxam in vitro and in vivo: Protective role of Trigonella foenum-graecum seed-derived polysaccharide.

The risk of pesticides on the human health and environment has drawn increasing attention. Today, new tools are developed to reduce pesticide adverse effects. This study aimed to evaluate the toxicity induced by, thiamethoxam (TMX), and the cytoprotective effect of a novel polysaccharide, named fenugreek seed water polysaccharide (FWEP) in vitro using H9c2 cardiomyoblastes and in vivo using Wistar rat model. Animals were assigned into four groups per eight rats each: group 1 served as a control group, group 2 received TMX, group 3, and group 4 received both FWEP and TMX tested at two doses (100 and 200 mg/kg, respectively). Regarding the in vitro study, our results demonstrated that TMX induced a decrease in H9c2 cell viability up to 70% with the highest concentration. In vivo, TMX injection induced marked heart damage noted by a significant increase in plasma lactate dehydrogenase, creatine phosphokinase, troponin-T, aspartate amino transferase activities, cholesterol, and triglyceride levels. Concomitant alterations in cardiac antioxidant defense system revealed depletion in the levels of glutathione and non-protein thiol and an increase in the activity of superoxide dismutase, catalase, and glutathione peroxidase. Similarly, a significant increase in heart lipid, malondialdehyde, advanced oxidation protein product and in protein carbonyls levels was also noted. In addition, heart tissues histo-architecture displayed major presence of apoptosis and necrosis as confirmed by DNA degradation. However, supplementation with FWEP alleviated heart oxidative damage and genotoxicity. In this manner, ABTS radical-scavenging activity, linoleic acid oxidation tests and heart genomic and DNA nicking assay had proved FWEP strong antioxidant potential. In conclusion, FWEP provided significant protection against TMX-induced heart injury, and could be a useful and efficient agent against cardiotoxicity and atherosclerosis.

Taiwanese and Japanese yam (Dioscorea spp.) extracts attenuate doxorubicin-induced cardiotoxicity in mice.

The present study was designed to explore whether yam could protect the heart from doxorubicin (DOX)-induced oxidative stress leading to cardiotoxicity in vivo. In this study, the protective effects of water and ethanol extracts of three varieties of yam, including water extracts of Dioscorea japonica Thunb., ethanol extracts of D. japonica Thunb., water extracts of Dioscorea alata, ethanol extracts of D. alata, water extracts of Dioscorea purpurea, and ethanol extracts of D. purpurea, against DOX-induced cardiotoxicity in experimental mice were evaluated. DOX treatment led to significant decreases in the ratio of heart weight to body weight and heart rate, and increases in blood pressure and the serum level of lactate dehydrogenase, a marker of cardiotoxicity, were recovered by yam extracts, especially in water extracts of D. alata. Yam extracts also decreased the cardiac levels of thiobarbituric acid relative substances, reactive oxygen species, and inflammatory factors, as well as the expression of nuclear factor kappa B, while ethanol extracts of D. japonica Thunb. and D. purpurea were shown to be more potent. Moreover, yam extracts had a role in increasing the activities of glutathione peroxidase and superoxide dismutase, thus improving the DOX-induced alterations in oxidative status in the heart tissue of DOX-treated mice. All ethanol extracts of yam exhibited their antiapoptotic abilities on caspase-3 activation and mitochondrial dysfunction, and ethanol extracts of D. alata still exerted a superior effect. Based on these findings, it can be concluded that yam has significant cardioprotective properties against DOX-induced damage via its multiple effects on antioxidant, anti-inflammatory, or antiapoptotic activities.

Mung bean (Phaseolus radiatus L.) polyphenol extract attenuates aluminum-induced cardiotoxicity through an ROS-triggered Ca2+/JNK/NF-κB signaling pathway in rats.

Aluminum (Al) has been linked to the development of some cardiovascular diseases and mung bean is a functional food with the ability to detoxify. We aimed to evaluate the preventive effect and possible underlying mechanisms of the mung bean polyphenol extract (MPE) on Al-induced cardiotoxicity. Control, AlCl3 (171.8 mg Al per kg body weight), MPE + AlCl3 (Al-treatment plus 200 mg MPE per kg body weight), and a group of MPE per se were used. Al intake induced a significant increase of serum CK and LDH activity and the level of Na+, Ca2+, malondialdehyde and advanced oxidation protein products in the AlCl3-treated rats' heart tissue. Administration of MPE significantly improved the integrity and normal ion levels of heart tissue, and attenuated oxidative damage and the accumulation of Al in Al-treated rats. MPE significantly inhibited Al-induced increase of myocardial p-JNK, cytoplasmic NF-κB, cytochrome C, and caspase-9 protein expressions. Therefore, these results showed that MPE has a cardiac protective effect against Al-induced biotoxicity through ROS-JNK and NF-κB-mediated caspase pathways. Furthermore, the stability constant for the vitexin-Al complex was analyzed (log K = log K1 + log K2 = 4.91 + 4.85 = 9.76). We found that MPE-mediated protection against Al-cardiotoxicity is connected both with MPE antioxidant and chelation properties.

Corresponding morphological and molecular indicators of crude oil toxicity to the developing hearts of mahi mahi.

Crude oils from distinct geological sources worldwide are toxic to developing fish hearts. When oil spills occur in fish spawning habitats, natural resource injury assessments often rely on conventional morphometric analyses of heart form and function. The extent to which visible indicators correspond to molecular markers for cardiovascular stress is unknown for pelagic predators from the Gulf of Mexico. Here we exposed mahi (Coryphaena hippurus) embryos to field-collected crude oil samples from the 2010 Deepwater Horizon disaster. We compared visible heart defects (edema, abnormal looping, reduced contractility) to changes in expression of cardiac-specific genes that are diagnostic of heart failure in humans or associated with loss-of-function zebrafish cardiac mutants. Mahi exposed to crude oil during embryogenesis displayed typical symptoms of cardiogenic syndrome as larvae. Contractility, looping, and circulatory defects were evident, but larval mahi did not exhibit downstream craniofacial and body axis abnormalities. A gradation of oil exposures yielded concentration-responsive changes in morphometric and molecular responses, with relative sensitivity being influenced by age. Our findings suggest that 1) morphometric analyses of cardiac function are more sensitive to proximal effects of crude oil-derived chemicals on the developing heart, and 2) molecular indicators reveal a longer-term adverse shift in cardiogenesis trajectory.