Doxorubicin targets multiple players: A new view of an old problem

Mechanisms of doxorubicin-induced cardiac inflammation and fibrosis; therapeutic targets and approaches

Doxorubicin plays a pivotal role in the treatment of various malignancies. Despite its efficacy, the cardiotoxicity associated with doxorubicin limits its clinical utility. The cardiotoxic nature of doxorubicin is attributed to several mechanisms, including its interference with mitochondrial function, the generation of reactive oxygen species (ROS), and the subsequent damage to cardiomyocyte DNA, proteins, and lipids. Furthermore, doxorubicin disrupts the homeostasis of cardiac-specific transcription factors and signaling pathways, exacerbating cardiac dysfunction. Oxidative stress, cell death, and other severe changes, such as mitochondrial dysfunction, activation of pro-oxidant enzymes, the renin-angiotensin system (RAS), endoplasmic reticulum (ER) stress, and infiltration of immune cells in the heart after treatment with doxorubicin, may cause inflammatory and fibrotic responses. Fibrosis and inflammation can lead to a range of disorders in the heart, resulting in potential cardiac dysfunction and disease. Various adjuvants have shown potential in preclinical studies to mitigate these challenges associated with cardiac inflammation and fibrosis. Antioxidants, plant-based products, specific inhibitors, and cardioprotective drugs may be recommended to alleviate cardiotoxicity. This review explores the complex mechanisms of doxorubicin-induced heart inflammation and fibrosis, identifies possible cellular and molecular targets, and investigates potential substances that could help reduce these harmful effects.

Anthracycline-induced cardiotoxicity: An overview from cellular structural perspective

Anthracyclines are broad-spectrum anticancer drugs, but their clinical use is limited due to their severe cardiotoxicity. Anthracycline-induced cardiotoxicity (AIC) remains a significant cause of heart disease-related mortality in many cancer survivors. The underlying mechanisms of AIC have been explored over the past few decades. Reactive oxygen species and drug-induced inhibition of topoisomerase II beta are well-studied mechanisms, with mitochondria being a prominently investigated organelle. Emerging mechanisms such as ferroptosis, Ca2+ overload, autophagy and inflammation mediators have been implicated in recent years. In this review, our goal is to summarize and update the roles of various mechanisms in AIC, focusing on different cellular levels and further explore promising therapeutic approaches targeting these organelles or pathways.

Nanotechnology Approaches for Prevention and Treatment of Chemotherapy-Induced Neurotoxicity, Neuropathy, and Cardiomyopathy in Breast and Ovarian Cancer Survivors

Nanotechnology has emerged as a promising approach for the targeted delivery of therapeutic agents while improving their efficacy and safety. As a result, nanomaterial development for the selective targeting of cancers, with the possibility of treating off-target, detrimental sequelae caused by chemotherapy, is an important area of research. Breast and ovarian cancer are among the most common cancer types in women, and chemotherapy is an essential treatment modality for these diseases. However, chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy are common side effects that can affect breast and ovarian cancer survivors quality of life. Therefore, there is an urgent need to develop effective prevention and treatment strategies for these adverse effects. Nanoparticles (NPs) have extreme potential for enhancing therapeutic efficacy but require continued research to elucidate beneficial interventions for women cancer survivors. In short, nanotechnology-based approaches have emerged as promising strategies for preventing and treating chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy. NP-based drug delivery systems and therapeutics have shown potential for reducing the side effects of chemotherapeutics while improving drug efficacy. In this article, the latest nanotechnology approaches and their potential for the prevention and treatment of chemotherapy-induced neurotoxicity, neuropathy, and cardiomyopathy in breast and ovarian cancer survivors are discussed.

Add-on multidrug treatment based on quadruple therapy successfully treated worsening heart failure caused by anthracycline-induced cardiomyopathy in a survivor of cancer as a young adult: a case report

BACKGROUND

The overall mortality and morbidity benefit in patients with heart failure with a reduced ejection fraction is greatest with a treatment combination of sacubitril/valsartan, beta-blockers, mineralocorticoid-receptor antagonists, and sodium-glucose transporter-2 inhibitors, termed the "fantastic four" or "quadruple therapy." The addition of vericiguat (an oral soluble guanylate cyclase stimulator) is believed to aid in managing worsening heart failure after quadruple therapy. Among childhood and young adult cancer survivors, cardiovascular complications that develop more than 10 years after anthracycline-based chemotherapy have a poor prognosis. Therefore, this study reports the efficacy of multidrug regimen based on quadruple therapy for worsening heart failure in cancer survivors with anthracycline-induced cardiomyopathy.

CASE PRESENTATION

A survivor of cancer as a young adult who received high-dose anthracycline chemotherapy presented with acute decompensated heart failure 20 years post-chemotherapy and worsening heart failure 1.5 years after discharge. The patient showed signs of improvement after a step-wise introduction of carvedilol, empagliflozin, sacubitril/valsartan, ivabradine, and spironolactone for worsening heart failure. Vericiguat was accelerated owing to the risk of more severe cardiovascular events associated with ongoing aortic stenosis and the poor prognosis of anthracycline-induced cardiomyopathy. Heart failure symptoms continued to improve, with significant cardiac reverse remodeling, and the patient successfully underwent aortic valve replacement for severe aortic stenosis.

CONCLUSIONS

Our case highlighted that multidrug treatment with add-on vericiguat and ivabradine based on quadruple therapy can potentially treat worsening heart failure in young adult cancer survivors with severe anthracycline-induced cardiomyopathy.

A Luminescent MOF-Based Sensor for Monitoring of an Anticancer Drug and a Pyrethroid Fungicide Biomarker in Wastewater and Biological Fluids

The extensive use of insecticides, such as pyrethroids, and pharmaceutical drugs, such as doxorubicin (DOX) has significantly increased to meet the growing demand for food production and disease treatment. Among them, 3-phenoxybenzoic acid (3-PBA), a metabolite of pyrethroid insecticides, poses various health and environmental risks. Similarly, DOX is a well-known anticancer drug and has been continuously used for many years. The high demand and unregulated disposal of these substances raise concerns for both humans and the environment. To address this issue, there is a pressing need to monitor the presence of these analytes in wastewater to protect our ecosystems. This challenge has inspired us to develop an MOF-based fluorometric dual sensor capable of rapid and selective detection of these analytes in aqueous solutions. This work represents the first MOF-based dual probe for detecting these targeted analytes. There was a 98% fluorescence quenching upon the introduction of DOX whereas about a 11-fold increment of the probe's fluorescence intensity took place in the presence of 3-PBA. The sensitivity of the probe is notably high as limits of detection (LOD) are 8.7 nM for DOX and 1.2 nM for 3-PBA. Our designed probe has the highest KSV value for DOX which is 3.37 × 106 M-1. The MOF demonstrated remarkable rapid response time of just 5 and 10 s for DOX and 3-PBA, respectively. The MOF exhibited outstanding selectivity in detecting DOX and 3-PBA, even when other interfering substances were present. We tested the probe's sensing abilities in various environments, such as serum, urine, wastewater, and different pH levels. These findings underscore the sensor's practicality and usefulness in real-world applications. The underlying mechanisms driving the sensing processes were thoroughly investigated by using various modern analytical methods.

A longitudinal evaluation of oxidative stress - mitochondrial dysfunction - ferroptosis genes in anthracycline-induced cardiotoxicity

BACKGROUND

Antineoplastic medications, including doxorubicin, idarubicin, and epirubicin, have been found to adversely affect the heart due to oxidative stress - mitochondrial dysfunction - ferroptosis (ORMFs), which act as contributing attributes to anthracycline-induced cardiotoxicity. To better understand this phenomenon, the time-resolved measurements of ORMFS genes were analyzed in this study.

METHODS

The effect of three anthracycline drugs on ORMFs genes was studied using a human 3D cardiac microtissue cell model. Transcriptome data was collected over 14 days at two doses (therapeutic and toxic). WGCNA identified key module-related genes, and functional enrichment analysis investigated the biological processes quantified by ssGSEA, such as immune cell infiltration and angiogenesis. Biopsies were collected from heart failure patients and control subjects. GSE59672 and GSE2965 were collected for validation. Molecular docking was used to identify anthracyclines's interaction with key genes.

RESULTS

The ORMFs genes were screened in vivo or in vitro. Using WGCNA, six co-expressed gene modules were grouped, with MEblue emerging as the most significant module. Eight key genes intersecting the blue module with the dynamic response genes were obtained: CD36, CDH5, CHI3L1, HBA2, HSD11B1, OGN, RPL8, and VWF. Compared with control samples, all key genes except RPL8 were down-regulated in vitro ANT treatment settings, and their expression levels varied over time. According to functional analyses, the key module-related genes were engaged in angiogenesis and the immune system pathways. In all ANT-treated settings, ssGSEA demonstrated a significant down-regulation of angiogenesis score and immune cell activity, including Activated CD4 T cell, Immature B cell, Memory B cell, Natural killer cell, Type 1 T helper cell, and Type 2 T helper cell. Molecular docking revealed that RPL8 and CHI3L1 show significant binding affinity for anthracyclines.

CONCLUSION

This study focuses on the dynamic characteristics of ORMFs genes in both human cardiac microtissues and cardiac biopsies from ANT-treated patients. It has been highlighted that ORMFs genes may contribute to immune infiltration and angiogenesis in cases of anthracycline-induced cardiotoxicity. A thorough understanding of these genes could potentially lead to improved diagnosis and treatment of the disease.

Semaglutide attenuates doxorubicin-induced cardiotoxicity by ameliorating BNIP3-Mediated mitochondrial dysfunction

AIMS

Doxorubicin is a powerful chemotherapeutic agent for cancer, whose use is limited due to its potential cardiotoxicity. Semaglutide (SEMA), a novel analog of glucagon-like peptide-1 (GLP-1), has received widespread attention for the treatment of diabetes. However, increasing evidence has highlighted its potential therapeutic benefits on cardiac function. Therefore, the objective of this study was to examine the efficacy of semaglutide in ameliorating doxorubicin-induced cardiotoxicity.

METHODS AND RESULTS

Doxorubicin-induced cardiotoxicity is an established model to study cardiac function. Cardiac function was studied by transthoracic echocardiography and invasive hemodynamic monitoring. The results showed that semaglutide significantly ameliorated doxorubicin-induced cardiac dysfunction. RNA sequencing suggested that Bnip3 is the candidate gene that impaired the protective effect of semaglutide in doxorubicin-induced cardiotoxicity. To determine the role of BNIP3 on the effect of semaglutide in doxorubicin-induced cardiotoxicity, BNIP3 with adeno-associated virus serotype 9 (AAV9) expressing cardiac troponin T (cTnT) promoter was injected into tail vein of C57/BL6J mice to overexpress BNIP3, specifically in the heart. Overexpression of BNIP3 prevented the improvement in cardiac function caused by semaglutide. In vitro experiments showed that semaglutide, via PI3K/AKT pathway, reduced BNIP3 expression in the mitochondria, improving mitochondrial function.

CONCLUSION

Semaglutide ameliorates doxorubicin-induced mitochondrial and cardiac dysfunction via PI3K/AKT pathway, by reducing BNIP3 expression in mitochondria. The improvement in mitochondrial function reduces doxorubicin-mediated cardiac injury and improves cardiac function. Therefore, semaglutide is a potential therapy to reduce doxorubicin-induced acute cardiotoxicity.

Primary Protection of Diosmin Against Doxorubicin Cardiotoxicity via Inhibiting Oxido-Inflammatory Stress and Apoptosis in Rats

Doxorubicin (DOX) is the cornerstone of chemotherapy. However, it has dose-dependent cardiotoxic events that limit its clinical use. This study was intended to investigate the efficiency of DOX as an anti-cancer against the MCF-7 cell line in the presence of diosmin (DIO) and to appraise the protective impact of DIO against DOX cardiotoxicity in vivo. In vitro study was carried out to establish the conservation of DOX cytotoxicity in the presence of DIO. In vivo study was conducted on 42 adult female Wistar rats that were equally allocated into 6 groups; control, DIO (100 mg/kg), DIO (200 mg/kg), DOX (20 mg/kg, single dose i.p.), DIO (100 mg/kg) + DOX, received DIO orally (100 mg/kg) for 30 days, then administrated with a single dose of DOX and DIO (200 mg/kg) + DOX, received DIO orally (200 mg/kg) for 30 days, then administrated with DOX. In vitro study showed preservation of cytotoxic activity of DOX on MCF-7 in the presence of DIO. In vivo study indicated that DOX altered electrocardiograph (ECG) parameters. Also, it yielded a significant rise in CK-MB, cTnT and LDH serum levels and cardiac contents of MDA, IL-1β; paralleled by a significant drop in cardiac IL-10 and SOD. Moreover, significant upregulation of Bax, TNF-α, and HIF-1α, in concomitant with significant downregulation of Bcl-2 mRNA in cardiac tissue have been recorded in the DOX group. Furthermore, histopathological description of cardiac tissues showed that DOX alters normal cardiac histoarchitecture. On the opposite side, DIO pretreatment could ameliorate ECG parameters, suppress IL-1β and enhanceIL-10, promote activity of SOD and repress MDA. Additionally, downregulation of Bax, TNF-α, HIF-1α and upregulation of Bcl-2 have been demonstrated in DIO-pretreated rats. Furthermore, the histopathological examination of cardiac tissues illustrated that DIO had a favorable impact on the protection of heart histoarchitecture. DIO is suggested for protection against acute cardiotoxicity caused by DOX without affecting antitumor activity.

Beneficial Effects of Oral Carbon Monoxide on Doxorubicin-Induced Cardiotoxicity

BACKGROUND

Doxorubicin and other anthracyclines are crucial cancer treatment drugs. However, they are associated with significant cardiotoxicity, severely affecting patient care and limiting dosage and usage. Previous studies have shown that low carbon monoxide (CO) concentrations protect against doxorubicin toxicity. However, traditional methods of CO delivery pose complex challenges for daily administration, such as dosing and toxicity. To address these challenges, we developed a novel oral liquid drug product containing CO (HBI-002) that can be easily self-administered by patients with cancer undergoing doxorubicin treatment, resulting in CO being delivered through the upper gastrointestinal tract.

METHODS AND RESULTS

HBI-002 was tested in a murine model of doxorubicin cardiotoxicity in the presence and absence of lung or breast cancer. The mice received HBI-002 twice daily before doxorubicin administration and experienced increased carboxyhemoglobin levels from a baseline of ≈1% to 7%. Heart tissue from mice treated with HBI-002 had a 6.3-fold increase in CO concentrations and higher expression of the cytoprotective enzyme heme oxygenase-1 compared with placebo control. In both acute and chronic doxorubicin toxicity scenarios, HBI-002 protected the heart from cardiotoxic effects, including limiting tissue damage and cardiac dysfunction and improving survival. In addition, HBI-002 did not compromise the efficacy of doxorubicin in reducing tumor volume, but rather enhanced the sensitivity of breast 4T1 cancer cells to doxorubicin while simultaneously protecting cardiac function.

CONCLUSIONS

These findings strongly support using HBI-002 as a cardioprotective agent that maintains the therapeutic benefits of doxorubicin cancer treatment while mitigating cardiac damage.

Cardiomyocytes, cardiac endothelial cells and fibroblasts contribute to anthracycline-induced cardiac injury through RAS-homologous small GTPases RAC1 and CDC42

The clinical use of the DNA damaging anticancer drug doxorubicin (DOX) is limited by irreversible cardiotoxicity, which depends on the cumulative dose. The RAS-homologous (RHO) small GTPase RAC1 contributes to DOX-induced DNA damage formation and cardiotoxicity. However, the pathophysiological relevance of other RHO GTPases than RAC1 and different cardiac cell types (i.e., cardiomyocytes, non-cardiomyocytes) for DOX-triggered cardiac damage is unclear. Employing diverse in vitro and in vivo models, we comparatively investigated the level of DOX-induced DNA damage in cardiomyocytes versus non-cardiomyocytes (endothelial cells and fibroblasts), in the presence or absence of selected RHO GTPase inhibitors. Non-cardiomyocytes exhibited the highest number of DOX-induced DNA double-strand breaks (DSB), which were efficiently repaired in vitro. By contrast, rather low levels of DSB were formed in cardiomyocytes, which however remained largely unrepaired. Moreover, DOX-induced apoptosis was detected only in non-cardiomyocytes but not in cardiomyocytes. Pharmacological inhibitors of RAC1 and CDC42 most efficiently attenuated DOX-induced DNA damage in all cell types examined in vitro. Consistently, immunohistochemical analyses revealed that the RAC1 inhibitor NSC23766 and the pan-RHO GTPase inhibitor lovastatin reduced the level of DOX-induced residual DNA damage in both cardiomyocytes and non-cardiomyocytes in vivo. Overall, we conclude that endothelial cells, fibroblasts and cardiomyocytes contribute to the pathophysiology of DOX-induced cardiotoxicity, with RAC1- and CDC42-regulated signaling pathways being especially relevant for DOX-stimulated DSB formation and DNA damage response (DDR) activation. Hence, we suggest dual targeting of RAC1/CDC42-dependent mechanisms in multiple cardiac cell types to mitigate DNA damage-dependent cardiac injury evoked by DOX-based anticancer therapy.

Combination Treatment with EGFR Inhibitor and Doxorubicin Synergistically Inhibits Proliferation of MCF-7 Cells and MDA-MB-231 Triple-Negative Breast Cancer Cells In Vitro

The role of the epidermal growth factor receptor (EGFR) in tumor progression and survival is often underplayed. Its expression and/or dysregulation is associated with disease advancement and poor patient outcome as well as drug resistance in breast cancer. EGFR is often overexpressed in breast cancer and particularly triple-negative breast cancer (TNBC), which currently lacks molecular targets. We examined the synergistic potential of an EGFR inhibitor (EGFRi) in combination with doxorubicin (Dox) in estrogen-positive (ER+) MCF-7 and MDA-MB-231 TNBC cell lines. The exposure of MDA-MB-231 and MCF-7 to EGFRi produced an IC50s of 6.03 µM and 3.96 µM, respectively. Dox induced MDA-MB-231 (IC50 9.67 µM) and MCF-7 (IC50 1.4 µM) cytotoxicity. Combinations of EGFRi-Dox significantly reduced the IC50 in MCF-7 (0.46 µM) and MBA-MB 231 (0.01 µM). Synergistic drug interactions in both cell lines were confirmed using the Bliss independence model. Pro-apoptotic Caspase-3/7 activation occurred in MCF-7 at 0.1-10 µM of EGFRi and Dox single treatments, whilst 1 μM Dox yielded a more potent effect on MDA-MB-231. EGFRi and Dox individually and in combination downregulated the EGFR gene expression in MCF-7 and MDA-MB-231 (p < 0.001). This study demonstrates EGFRi's potential for eliciting synergistic interactions with Dox, causing enhanced growth inhibition, apoptosis induction, and downregulation of EGFR in both cell lines.

Role of Nutraceuticals in Counteracting Inflammation in In Vitro Macrophages Obtained from Childhood Cancer Survivors

The advancement of anti-cancer therapies has markedly improved the survival rate of children with cancer, making them long-term childhood cancer survivors (CCS). Nevertheless, these treatments cause a low-grade inflammatory state, determining inflamm-aging and, thus, favoring the early onset of chronic diseases normally associated with old age. Identification of novel and safer therapeutic strategies is needed to counteract and prevent inflamm-aging. Macrophages are cells involved in immune and inflammatory responses, with a pivotal role in iron metabolism, which is related to inflammation. We obtained macrophages from CCS patients and evaluated their phenotype markers, inflammatory states, and iron metabolism by Western blotting, ELISA, and iron assays. We observed a strong increase in classically activated phenotype markers (M1) and iron metabolism alteration in CCS, with an increase in intracellular iron concentration and inflammatory markers. These results suggest that the prevalence of M1 macrophages and alteration of iron metabolism could be involved in the worsening of inflammation in CCS. Therefore, we propose macrophages and iron metabolism as novel therapeutic targets to counteract inflamm-aging. To avoid toxic regimens, we tested some nutraceuticals (resveratrol, curcumin, and oil-enriched lycopene), which are already known to exert anti-inflammatory properties. After their administration, we observed a macrophage switch towards the anti-inflammatory phenotype M2, as well as reductions in pro-inflammatory cytokines and the intracellular iron concentration. Therefore, we suggest-for the first time-that nutraceuticals reduce inflammation in CCS macrophages through a novel anti-inflammatory mechanism of action, modulating iron metabolism.

A prospective randomized controlled trial to determine the safety and efficacy of extracorporeal shock waves therapy for primary prevention of subclinical cardiotoxicity in breast cancer patients without a cardiovascular risk treated with doxorubicin

Background

Doxorubicin is a highly effective anti-cancer drug that causes left ventricular (LV) dysfunction and induces late-onset cardiomyopathy. However, an effective and clinically applicable preventive treatment is yet to be discovered.

Objective

Cardiac-Extracorporeal shockwave therapy (C-ESWT) has been suggested to treat inflammatory and ischemic diseases and protect cardiomyocytes from doxorubicin-induced cardiomyopathy. This study aims to assess the safety and efficacy of C-ESWT in the prevention of subclinical cardiotoxicity.

Methods

We enrolled 64 breast cancer patients. C-ESWT group 33 patients were treated with our C-ESWT (200 shots/spot at 0.09 mJ/mm2 for 20 spots, 3 times every six weeks). The efficacy endpoints were the difference in left ventricular global longitudinal strain (LVGLS) change by 2D speckle tracking echocardiography and chemotherapy-related cardiac dysfunction (CTRCD). Echocardiography was performed on the baseline line and every 4 cycles of chemotherapy, followed by a follow-up 3,6 months after chemotherapy to compare the incidence of cardiomyopathy of subclinical LV dysfunction due to chemotherapy between the two groups.

Results

Participants averaged 50 ± 9 years in age, 100% female. In the results of follow-up 6 months after the end of chemotherapy, there was a significant difference in delta LVGLS between the C-ESWT group and the control group (LVGLS; -1.1 ± 10.9% vs. -11.5 ± 11.6% p-value; <0.001). A total of 23% (15 patients) of patients developed CTRCD (Control group; 13 vs. C-ESWT group; (2). C-ESWT was performed safely without any serious adverse events.

Conclusion

In this prospective study, C-ESWT established efficacy in preventing subclinical cardiotoxicity, especially in breast cancer patients using doxorubicin chemotherapy, and the safety of C-ESWT.

Clinical Trial Registration

ClinicalTrials.gov, identifier (NCT05584163).

A new perspective in the prevention and treatment of antitumor therapy-related cardiotoxicity: Intestinal microecology

The continuous development of antitumor therapy has significantly reduced the mortality of patients with malignancies. However, the antitumor-related cardiotoxicity has become the leading cause of long-term mortality in patients with malignancies. Besides, the pathogenesis of antitumor-related cardiotoxicity is still unclear, and practical means of prevention and treatment are lacking in clinical practice. Therefore, the major challenge is how to combat the cardiotoxicity of antitumor therapy effectively. More and more studies have shown that antitumor therapy kills tumor cells while causing damage to sensitive tissues such as the intestinal mucosa, leading to the increased permeability of the intestine and the dysbiosis of intestinal microecology. In addition, the dysbiosis of intestinal microecology contributes to the development and progression of cardiovascular diseases through multiple pathways. Thus, the dysbiosis of intestinal microecology may be a potential mechanism and target for antitumor-related cardiotoxicity. We summarized the characteristics of intestinal microecology disorders induced by antitumor therapy and the association between intestinal microecological dysbiosis and CVD. And on this basis, we hypothesized the potential mechanisms of intestinal microecology mediating the occurrence of antitumor-related cardiotoxicity. Then we reviewed the previous studies targeting intestinal microecology against antitumor-associated cardiotoxicity, aiming to provide a reference for future studies on the occurrence and prevention of antitumor-related cardiotoxicity by intestinal microecology.

Facile Fabrication of NIR-Responsive Alginate/CMC Hydrogels Derived through IEDDA Click Chemistry for Photothermal-Photodynamic Anti-Tumor Therapy

Novel chemically cross-linked hydrogels derived from carboxymethyl cellulose (CMC) and alginate (Alg) were prepared through the utilization of the norbornene (Nb)-methyl tetrazine (mTz) click reaction. The hydrogels were designed to generate reactive oxygen species (ROS) from an NIR dye, indocyanine green (ICG), for combined photothermal and photodynamic therapy (PTT/PDT). The cross-linking reaction between Nb and mTz moieties occurred via an inverse electron-demand Diels-Alder chemistry under physiological conditions avoiding the need for a catalyst. The resulting hydrogels exhibited viscoelastic properties (G' ~ 492-270 Pa) and high porosity. The hydrogels were found to be injectable with tunable mechanical characteristics. The ROS production from the ICG-encapsulated hydrogels was confirmed by DPBF assays, indicating a photodynamic effect (with NIR irradiation at 1-2 W for 5-15 min). The temperature of the ICG-loaded hydrogels also increased upon the NIR irradiation to eradicate tumor cells photothermally. In vitro cytocompatibility assessments revealed the non-toxic nature of CMC-Nb and Alg-mTz towards HEK-293 cells. Furthermore, the ICG-loaded hydrogels effectively inhibited the metabolic activity of Hela cells after NIR exposure.

Supervised exercise training in patients with cancer during anthracycline-based chemotherapy to mitigate cardiotoxicity: a randomized-controlled-trial

Background

Exercise training (ET) has been shown to mitigate cardiotoxicity of anthracycline-based chemotherapies (AC) in animal models. Data from randomized controlled trials in patients with cancer are sparse.

Methods

Patients with breast cancer or lymphoma receiving AC were recruited from four cancer centres and randomly assigned to 3 months supervised ET. Primary outcome was change in left ventricular global longitudinal strain (GLS) from baseline (before AC) to post AC (AC-end) compared between the EXduringAC group, who participated in an exercise intervention during AC including the provision of an activity tracker, and the control group EXpostAC, who received an activity tracker only. Secondary outcome parameters were changes in high sensitivity Troponin T (hsTnT), NT-pro-brain natriuretic peptide (NT-proBNP), peak oxygen consumption (peak VO2) and objectively measured physical activity (PA) during this same time-period. All assessments were repeated at a 12-week follow-up from AC-end, when also the EXpostAC group had completed the ET, that started after AC. In exploratory analyses, robust linear models were performed to assess the association of PA with changes in echocardiographic parameters and biomarkers of LV function.

Results

Fifty-seven patients (median age 47 years; 95% women) were randomized to EXduringAC (n = 28) and EXpostAC (n = 29) group. At AC-end, GLS deteriorated in both study groups (albeit insignificantly) with 7.4% and 1.0% in EXduringAC (n = 18) and EXpostAC (n = 18), respectively, and hsTnT and NT-proBNP significantly increased in both groups, without difference between groups for any parameter. Change in peak VO2 (-1.0 and -1.1 ml/kg/min) at AC-end was also similar between groups as was duration of moderate-to-vigorous PA (MVPA) with a median of 33 [26, 47] min/day and 32 [21, 59] min/day in the EXduringAC and EXpostAC group, respectively. In the robust linear model including the pooled patient population, MVPA was significantly associated with a more negative GLS and lesser increase in hsTnT at AC-end.

Conclusion

In this small scale RCT, supervised ET during AC was not superior to wearing a PA tracker to mitigate cardiotoxicity. The dose-response relationship between PA and cardioprotective effects during AC found in our and previous data supports the notion that PA should be recommended to patients undergoing AC.

Clinical Trial Registration

ClinicalTrials.gov, identifier NCT03850171.

Wnt10b protects cardiomyocytes against doxorubicin-induced cell death via MAPK modulation

BACKGROUND

Doxorubicin, an anthracycline chemotherapeutic known to incur heart damage, decreases heart function in up to 11% of patients. Recent investigations have implicated the Wnt signaling cascade as a key modulator of cardiac tissue repair after myocardial infarction. Wnt upregulation in murine models resulted in stimulation of angiogenesis and suppression of fibrosis after ischemic insult. However, the molecular mechanisms of Wnt in mitigating doxorubicin-induced cardiac insult require further investigation. Identifying cardioprotective mechanisms of Wnt is imperative to reducing debilitating cardiovascular adverse events in oncologic patients undergoing treatment.

METHODS

Exposing human cardiomyocyte AC16 cells to varying concentrations of Wnt10b and DOX, we observed key metrics of cell viability. To assess the viability and apoptotic rates, we utilized MTT and TUNEL assays. We quantified cell and mitochondrial membrane stability via LDH release and JC-1 staining. To investigate how Wnt10b mitigates doxorubicin-induced apoptosis, we introduced pharmacologic inhibitors of key enzymes involved in apoptosis: FR180204 and SB203580, ERK1/2 and p38 inhibitors. Further, we quantified apoptotic executor enzymes, caspase 3/7, via immunofluorescence.

RESULTS

AC16 cells exposed solely to doxorubicin were shrunken with distorted morphology. Cardioprotective effects of Wnt10b were demonstrated via a reduction in apoptosis, from 70.1% to 50.1%. LDH release was also reduced between doxorubicin and combination groups from 2.27-fold to 1.56-fold relative to the healthy AC16 control group. Mitochondrial membrane stability was increased from 0.67-fold in the doxorubicin group to 5.73 in co-treated groups relative to control. Apoptotic protein expression was stifled by Wnt10b, with caspase3/7 expression reduced from 2.4- to 1.3-fold, and both a 20% decrease in p38 and 40% increase in ERK1/2 activity.

CONCLUSION

Our data with the AC16 cell model demonstrates that Wnt10b provides defense mechanisms against doxorubicin-induced cardiotoxicity and apoptosis. Further, we explain a mechanism of this beneficial effect involving the mitochondria through simultaneous suppression of pro-apoptotic p38 and anti-apoptotic ERK1/2 activities.

Longitudinal strain analysis for assessment of early cardiotoxicity during anthracycline treatment in childhood sarcoma: A single center experience

BACKGROUND

The growing population of long-term childhood cancer survivors encounter a substantial burden of cardiovascular complications. The highest risk of cardiovascular complications is associated with exposure to anthracyclines and chest radiation. Longitudinal cardiovascular surveillance is recommended for childhood cancer patients; however, the optimal methods and timing are yet to be elucidated.

AIMS

We aimed to investigate the feasibility of different echocardiographic methods to evaluate left ventricular systolic function in retrospective datasets, including left ventricular ejection fraction (LVEF), fractional shortening (FS), global longitudinal strain (GLS) and longitudinal strain (LS) as well as the incidence and timing of subclinical left ventricular dysfunction detected by these methods.

METHODS AND RESULTS

A retrospective longitudinal study was performed with re-analysis of longitudinal echocardiographic data, acquired during treatment and early follow-up, including 41 pediatric sarcoma patients, aged 2.1-17.8 years at diagnosis, treated at Astrid Lindgren Children's Hospital, Stockholm, Sweden, during the period 2010-2021. All patients had received treatment according to protocols including high cumulative doxorubicin equivalent doses (≥250 mg/m2 ). In 68% of all 366 echocardiograms, LS analysis was feasible. Impaired LS values (<17%) was demonstrated in >40%, with concomitant impairment of either LVEF or FS in 20% and combined impairment of both LVEF and FS in <10%. Importantly, there were no cases of abnormal LVEF and FS without concomitant LS impairment.

CONCLUSION

Our findings demonstrate feasibility of LS in a majority of echocardiograms and a high incidence of impaired LS during anthracycline treatment for childhood sarcoma. We propose inclusion of LS in pediatric echocardiographic surveillance protocols.

MicroRNA‑378: An important player in cardiovascular diseases (Review)

Cardiovascular disease (CVD) is a common chronic clinical condition and is the main cause of death in humans worldwide. Understanding the genetic and molecular mechanisms involved in the development of CVD is essential to develop effective prevention strategies and therapeutic measures. An increasing number of CVD‑related genetic studies have been conducted, including those on the potential roles of microRNAs (miRs). These studies have demonstrated that miR‑378 is involved in the pathological processes of CVD, including those of myocardial infarction, heart failure and coronary heart disease. Despite the potential importance of miR‑378 CVD, a comprehensive summary of the related literature is lacking. Thus, the present review aimed to summarize the findings of previous studies on the roles and mechanisms of miR‑378 in a variety of CVDs and provide an up‑to date basis for further r research targeting the prevention and treatment of CVDs.

Doxorubicin Dose-Dependent Impact on Physiological Balance-A Holistic Approach in a Rat Model

Doxorubicin (DOX) is commonly used in several chemotherapies to treat various cancers, but it is known to cause cardiotoxicity and cardiac symptoms. Autonomic dysfunction is thought to contribute to the cardiotoxic effects of DOX, but the specific dose required to disrupt homeostatic processes is still unclear and is influenced by numerous factors. This study aimed to investigate how the DOX dosage affects autonomic function and physiological parameters, to elucidate the neurocardiac mechanisms underlying the observed cardiovascular side effects. Wistar rats were treated with DOX for four weeks and divided into three dosing groups: DOX8 (2 mg/kg/week), DOX16 (4 mg/kg/week), and DOX20 (5 mg/kg/week). A control group received NaCl 0.9% saline (1 mL/kg/week). In an acute experiment, we recorded blood pressure (BP), electrocardiogram, heart rate (HR), and respiratory rate (RF). Baroreflex gain and chemoreflex sensitivity were calculated, and cardiac tissue was analyzed with picrosirius histochemistry to measure collagen content. Our results showed that the LF/HF ratio, indicative of autonomic activity, was altered along with hypotension and bradycardia at a cumulative DOX dose threshold of 16 mg/kg. We observed a positive correlation between DOX dose and BP, HR, urinary norepinephrine, LF/HF ratio, and fibrotic heart area. Lower LF/HF ratios were associated with high DOX doses, reflecting drug-induced impairment of autonomic control of HR. This study provides valuable insights into the dose-dependent effects of DOX on physiological parameters and the development of cardiovascular dysfunction. These findings are critical, which is important for optimizing the management and therapeutic strategies for patients undergoing DOX-based chemotherapy.

Amentoflavone mitigates doxorubicin-induced cardiotoxicity by suppressing cardiomyocyte pyroptosis and inflammation through inhibition of the STING/NLRP3 signalling pathway

BACKGROUND

Doxorubicin (DOX) is a potent anticancer chemotherapeutic agent whose clinical application is substantially constrained by its cardiotoxicity. The pathophysiology of DOX-induced cardiotoxicity manifests as cardiomyocyte pyroptosis and inflammation. Amentoflavone (AMF) is a naturally occurring biflavone possessing anti-pyroptotic and anti-inflammatory properties. However, the mechanism through which AMF alleviates DOX-induced cardiotoxicity remains undetermined.

PURPOSE

This study aimed at investigating the role of AMF in alleviating DOX-induced cardiotoxicity.

STUDY DESIGN AND METHODS

To assess the in vivo effect of AMF, DOX was intraperitoneally administered into a mouse model to induce cardiotoxicity. To elucidate the underlying mechanisms, the activities of STING/NLRP3 were quantified using the NLRP3 agonist nigericin and the STING agonist amidobenzimidazole (ABZI). Primary cardiomyocytes isolated from neonatal Sprague-Dawley rats were treated with saline (vehicle) or DOX with or without AMF and/or ABZI. The echocardiogram, haemodynamics, cardiac injury markers, heart/body weight ratio, and pathological alterations were monitored; the STING/NLRP3 pathway-associated proteins were detected by western blot and cardiomyocyte pyroptosis was analysed by immunofluorescence staining of cleaved N-terminal GSDMD and scanning electron microscopy. Furthermore, we evaluated the potential of AMF in compromising the anticancer effects of DOX in human breast cancer cell lines.

RESULTS

AMF substantially alleviated cardiac dysfunction and reduced heart/body weight ratio and myocardial damage in mice models of DOX-induced cardiotoxicity. AMF effectively suppressed DOX-mediated upregulation of IL-1β, IL-18, TNF-α, and pyroptosis-related proteins, including NLRP3, cleaved caspase-1, and cleaved N-terminal GSDMD. The levels of apoptosis-related proteins, namely Bax, cleaved caspase-3, and BCL-2 were not affected. In addition, AMF inhibited STING phosphorylation in DOX-affected hearts. Intriguingly, the administration of nigericin or ABZI dampened the cardioprotective effects of AMF. The in vitro anti-pyroptotic effect of AMF was demonstrated in attenuating the DOX-induced reduction in cardiomyocyte cell viability, upregulation of cleaved N-terminal GSDMD, and pyroptotic morphology alteration at the microstructural level. AMF exhibited a synergistic effect with DOX to reduce the viability of human breast cancer cells.

CONCLUSION

AMF alleviates DOX-induced cardiotoxicity by suppressing cardiomyocyte pyroptosis and inflammation via inhibition of the STING/NLRP3 signalling pathway, thereby validating its efficacy as a cardioprotective agent.

An integrative review of nonobvious puzzles of cellular and molecular cardiooncology

Oncologic patients are subjected to four major treatment types: surgery, radiotherapy, chemotherapy, and immunotherapy. All nonsurgical forms of cancer management are known to potentially violate the structural and functional integrity of the cardiovascular system. The prevalence and severity of cardiotoxicity and vascular abnormalities led to the emergence of a clinical subdiscipline, called cardiooncology. This relatively new, but rapidly expanding area of knowledge, primarily focuses on clinical observations linking the adverse effects of cancer therapy with deteriorated quality of life of cancer survivors and their increased morbidity and mortality. Cellular and molecular determinants of these relations are far less understood, mainly because of several unsolved paths and contradicting findings in the literature. In this article, we provide a comprehensive view of the cellular and molecular etiology of cardiooncology. We pay particular attention to various intracellular processes that arise in cardiomyocytes, vascular endothelial cells, and smooth muscle cells treated in experimentally-controlled conditions in vitro and in vivo with ionizing radiation and drugs representing diverse modes of anti-cancer activity.

Anticancer Drug Doxorubicin Spontaneously Reacts with GTP and dGTP

Here, we reported a spontaneous reaction between anticancer drug doxorubicin and GTP or dGTP. Incubation of doxorubicin with GTP or dGTP at 37 °C or above yields a covalent product: the doxorubicin-GTP or -dGTP conjugate where a covalent bond is formed between the C14 position of doxorubicin and the 2-amino group of guanine. Density functional theory calculations show the feasibility of this spontaneous reaction. Fluorescence imaging studies demonstrate that the doxorubicin-GTP and -dGTP conjugates cannot enter nuclei although they rapidly accumulate in human SK-OV-3 and NCI/ADR-RES cells. Consequently, the doxorubicin-GTP and -dGTP conjugates are less cytotoxic than doxorubicin. We also demonstrate that doxorubicin binds to ATP, GTP, and other nucleotides with a dissociation constant (Kd) in the sub-millimolar range. Since human cells contain millimolar levels of ATP and GTP, these results suggest that doxorubicin may target ATP and GTP, energy molecules that support essential processes in living organisms.

Senescent cardiac fibroblasts: A key role in cardiac fibrosis

Cardiac fibroblasts are a cell population that controls the homeostasis of the extracellular matrix and orchestrates a damage response to maintain cardiac architecture and performance. Due to these functions, fibroblasts play a central role in cardiac fibrosis development, and there are large differences in matrix protein secretion profiles between fibroblasts from aged versus young animals. Senescence is a multifactorial and complex process that has been associated with inflammatory and fibrotic responses. After damage, transient cellular senescence is usually beneficial, as these cells promote tissue repair. However, the persistent presence of senescent cells within a tissue is linked with fibrosis development and organ dysfunction, leading to aging-related diseases such as cardiovascular pathologies. In the heart, early cardiac fibroblast senescence after myocardial infarction seems to be protective to avoid excessive fibrosis; however, in non-infarcted models of cardiac fibrosis, cardiac fibroblast senescence has been shown to be deleterious. Today, two new classes of drugs, termed senolytics and senostatics, which eliminate senescent cells or modify senescence-associated secretory phenotype, respectively, arise as novel therapeutical strategies to treat aging-related pathologies. However, further studies will be needed to evaluate the extent of the utility of senotherapeutic drugs in cardiac diseases, in which pathological context and temporality of the intervention must be considered.

Differential expression of epigenetic modifiers in early and late cardiotoxic heart failure reveals DNA methylation as a key regulator of cardiotoxicity

Background

Anthracycline-induced cardiotoxicity is a well-known serious clinical entity. However, detailed mechanistic insights on how short-term administration leads to late and long-lasting cardiotoxicity, are still largely undiscovered. We hypothesize that chemotherapy provokes a memory effect at the level of epigenomic DNA modifications which subsequently lead to cardiotoxicity even years after cessation of chemotherapy.

Methods

We explored the temporal evolution of epigenetic modifiers in early and late cardiotoxicity due to anthracyclines by means of RNA-sequencing of human endomyocardial left ventricular biopsies and mass spectrometry of genomic DNA. Based on these findings, validation of differentially regulated genes was obtained by performing RT-qPCR. Finally, a proof-of-concept in vitro mechanistic study was performed to dissect some of the mechanistic aspects of epigenetic memory in anthracycline-induced cardiotoxicity.

Results

Correlation of gene expression between late and early onset cardiotoxicity revealed an R2 value of 0.98, demonstrating a total of 369 differentially expressed genes (DEGs, FDR &lt; 0.05). of which 72% (n = 266) were upregulated, and 28% of genes, (n = 103) downregulated in later as compared to earlier onset cardiotoxicity. Gene ontology analysis showed significant enrichment of genes involved in methyl-CpG DNA binding, chromatin remodeling and regulation of transcription and positive regulation of apoptosis. Differential mRNA expression of genes involved in DNA methylation metabolism were confirmed by RT-qPCR in endomyocardial biopsies. In a larger biopsy cohort, it was shown that Tet2 was more abundantly expressed in cardiotoxicity biopsies vs. control biopsies and vs. non-ischemic cardiomyopathy patients. Moreover, an in vitro study was performed: following short-term doxorubicin treatment, H9c2 cells were cultured and passaged once they reached a confluency of 70%–80%. When compared to vehicle-only treated cells, in doxorubicin-treated cells, three weeks after short term treatment, Nppa, Nppb, Tet1/2 and other genes involved in active DNA demethylation were markedly upregulated. These alterations coincided with a loss of DNA methylation and a gain in hydroxymethylation, reflecting the epigenetic changes seen in the endomyocardial biopsies.

Conclusions

Short-term administration of anthracyclines provokes long-lasting epigenetic modifications in cardiomyocytes both in vivo and in vitro, which explain in part the time lapse between the use of chemotherapy and the development of cardiotoxicity and, eventually, heart failure.

Efficacy and safety of cardioprotective drugs in chemotherapy-induced cardiotoxicity: an updated systematic review & network meta-analysis

BACKGROUND

Cancer patients receiving chemotherapy have an increased risk of cardiovascular complications. This limits the widespread use of lifesaving therapies, often necessitating alternate lower efficacy regimens, or precluding chemotherapy entirely. Prior studies have suggested that using common cardioprotective agents may attenuate chemotherapy-induced cardiotoxicity. However, small sample sizes and conflicting outcomes have limited the clinical significance of these results.

HYPOTHESIS

A comprehensive network meta-analysis using updated and high-quality data can provide more conclusive information to assess which drug or drug class has the most significant effect in the management of chemotherapy-induced cardiotoxicity.

METHODS

We performed a literature search for randomized controlled trials (RCTs) investigating the effects of cardioprotective agents in patients with chemotherapy-induced cardiotoxicity. We used established analytical tools (netmeta package in RStudio) and data extraction formats to analyze the outcome data. To obviate systematic bias in the selection and interpretation of RCTs, we employed the validated Cochrane risk-of-bias tools. Agents included were statins, aldosterone receptor antagonists (MRAs), ACEIs, ARBs, and beta-blockers. Outcomes examined were improvement in clinical and laboratory parameters of cardiac function including a decreased reduction in left ventricular ejection fraction (LVEF), clinical HF, troponin-I, and B-natriuretic peptide levels.

RESULTS

Our study included 33 RCTs including a total of 3,285 patients. Compared to control groups, spironolactone therapy was associated with the greatest LVEF improvement (Mean difference (MD) = 12.80, [7.90; 17.70]), followed by enalapril (MD = 7.62, [5.31; 9.94]), nebivolol (MD = 7.30, [2.39; 12.21]), and statins (MD = 6.72, [3.58; 9.85]). Spironolactone was also associated with a significant reduction in troponin elevation (MD =  - 0.01, [- 0.02; - 0.01]). Enalapril demonstrated the greatest BNP reduction (MD =  - 49.00, [- 68.89; - 29.11]), which was followed by spironolactone (MD =  - 16.00, [- 23.9; - 8.10]). Additionally, patients on enalapril had the lowest risk of developing clinical HF compared to the control population (RR = 0.05, [0.00; 0.75]).

CONCLUSION

Our analysis reaffirmed that statins, MRAs, ACEIs, and beta-blockers can significantly attenuate chemotherapy-induced cardiotoxicity, while ARBs showed no significant effects. Spironolactone showed the most robust improvement of LVEF, which best supports its use among this population. Our analysis warrants future clinical studies examining the cardioprotective effects of cardiac remodeling therapy in cancer patients treated with chemotherapeutic agents.

Berberine Alleviates Doxorubicin-Induced Myocardial Injury and Fibrosis by Eliminating Oxidative Stress and Mitochondrial Damage via Promoting Nrf-2 Pathway Activation

Doxorubicin (DOX)-related cardiotoxicity has been recognized as a serious complication of cancer chemotherapy. Effective targeted strategies for myocardial protection in addition to DOX treatment are urgently needed. The purpose of this paper was to determine the therapeutic effect of berberine (Ber) on DOX-triggered cardiomyopathy and explore the underlying mechanism. Our data showed that Ber markedly prevented cardiac diastolic dysfunction and fibrosis, reduced cardiac malondialdehyde (MDA) level and increased antioxidant superoxide dismutase (SOD) activity in DOX-treated rats. Moreover, Ber effectively rescued the DOX-induced production of reactive oxygen species (ROS) and MDA, mitochondrial morphological damage and membrane potential loss in neonatal rat cardiac myocytes and fibroblasts. This effect was mediated by increases in the nuclear accumulation of nuclear erythroid factor 2-related factor 2 (Nrf2) and levels of heme oxygenase-1 (HO-1) and mitochondrial transcription factor A (TFAM). We also found that Ber suppressed the differentiation of cardiac fibroblasts (CFs) into myofibroblasts, as indicated by decreased expression of α-smooth muscle actin (α-SMA), collagen I and collagen III in DOX-treated CFs. Pretreatment with Ber inhibited ROS and MDA production and increased SOD activity and the mitochondrial membrane potential in DOX-challenged CFs. Further investigation indicated that the Nrf2 inhibitor trigonelline reversed the protective effect of Ber on both cardiomyocytes and CFs after DOX stimulation. Taken together, these findings demonstrated that Ber effectively alleviated DOX-induced oxidative stress and mitochondrial damage by activating the Nrf2-mediated pathway, thereby leading to the prevention of myocardial injury and fibrosis. The current study suggests that Ber is a potential therapeutic agent for DOX-induced cardiotoxicity that exerts its effects by activating Nrf2.

Nifuroxazide mitigates doxorubicin-induced cardiovascular injury: Insight into oxidative/NLRP3/GSDMD-mediated pyroptotic signaling modulation

Doxorubicin (DOX) is a widely used powerful anthracycline for treatment of many varieties of malignancies; however its cumulative and dose-dependent cardio-toxicity has been limited its clinical use. In the current study, in vivo and in vitro (neonatal rat's cardiomyocytes) experiments were conducted to identify the impact of nifuroxazide (NIFU) on DOX-induced cardiomyopathy, vascular injury, and hemato-toxcity and plot the underlying regulatory mechanisms. Cardiovascular injury was induced in vivo by I.P. injection of an overall dose of DOX (21 mg/kg) administered (3.5 mg/kg) twice weekly for 21 days. NIFU (10 and 30 mg/kg) was administered orally once daily for 21 days, 1 week after DOX injection initiation. In vivo experiments confirmed NIFU to restore blood cells counts and hemoglobin concentration. Moreover, NIFU normalized the myocardial functional status as confirmed by ECG examination and myocardial injury markers; CK-MB, LDH, and AST. NIFU restored the balance between TAC and both of ROS and MDA and down-regulated the protein expression of TLR4, NF-kB, TXNIP, NLR-family pyrin domain containing 3 (NLRP3), caspase-1, IL-1β, and GSDMD-N terminal, with inhibition of the up-stream of NLRP3 and the down-stream DOX-induced pyroptosis. The in vitro assay confirmed well preserved cardiomyocytes' architecture, amelioration of NLRP3/IL-1 β-mediated cell pyroptosis, enhanced cell viability, and improved spontaneous beating. Moreover, NIFU normalized the disturbed aortic oxidant-antioxidant balance; enhanced eNOS- mediated endothelial relaxation, and down regulated IL-1β expression. Thus, NIFU may be proposed to serve as a cardioprotective agent to attenuate DOX-induced cardio-toxicity and vascular injury.

Cardioprotective Effect of Centaurea castriferrei Borbás & Waisb Extract against Doxorubicin-Induced Cardiotoxicity in H9c2 Cells

Doxorubicin (DOX) is one of the most used chemotherapeutic agents in the treatment of various types of cancer. However, a continual problem that is associated with its application in therapeutic regimens is the development of dose-dependent cardiotoxicity. The progression of this process is associated with a range of different mechanisms, but especially with the high level of oxidative stress. The aim of the study was to evaluate the effects of the water and methanol-water extracts from the plant Centaurea castriferrei (CAS) obtained by the ultrasound-assisted extraction method on the DOX-induced cardiotoxicity in the rat embryonic cardiomyocyte cell line H9c2. The H9c2 cells were treated for 48 h with the DOX and water or methanol-water extracts, or a combination (DOX + CAS H2O/CAS MeOH). The MTT assay, cell cycle analysis, and apoptosis detection revealed that both the tested extracts significantly abolished the cytotoxic effect caused by DOX. Moreover, the detection of oxidative stress by the CellROX reagent, the evaluation of the number of AP sites, and the expressions of the genes related to the oxidative stress defense showed substantial reductions in the oxidative stress levels in the H9c2 cells treated with the combination of DOX and CAS H2O/CAS MeOH compared with the DOX administered alone. The tested extracts did not affect the cytotoxic effect of DOX on the MCF-7 breast cancer cell line. The obtained results constitute the basis for further research in the context of the application of C. castriferrei extracts as adjuvants in the therapy regiments of cancer patients treated with DOX.

Temperature- and pH-responsive injectable chitosan hydrogels loaded with doxorubicin and curcumin as long-lasting release platforms for the treatment of solid tumors

The efficacy of treating solid tumors with chemotherapy is primarily hindered by dose-limiting toxicity due to off-target effects and the heterogeneous drug distribution caused by the dense extracellular matrix. The enhanced permeability and retention (EPR) effect within tumors restricts the circulation and diffusion of drugs. To overcome these obstacles, hydrogels formed in situ at the tumor site have been proposed to promote drug accumulation, retention, and long-lasting release. We developed a thiolated chitosan (CSSH) hydrogel with a gelation point of 37°C. Due to the pH-sensitive characteristics of disulfides, the prepared hydrogel facilitated drug release in the acidic tumor environment. A drug release system composed of hydrophilic doxorubicin (Dox) and hydrophobic liposome-encapsulated curcumin (Cur-Lip) was designed to enhance the long-lasting therapeutic impacts and reduce adverse side effects. These composite gels possess a suitable gelation time of approximately 8-12 min under physiological conditions. The cumulative release ratio was higher at pH = 5.5 than at pH = 7.4 over the first 24 h, during which approximately 10% of the Dox was released, and Cur was released slowly over the following 24-120 h. Cell assays indicated that the Cur-Lip/Dox/CSSH gels effectively inhibited the growth of cancer cells. These in situ-formed Cur-Lip/Dox gels with long-term drug release capabilities have potential applications for tumor suppression and tissue regeneration after surgical tumor resection.

Natural compound glycyrrhetinic acid protects against doxorubicin-induced cardiotoxicity by activating the Nrf2/HO-1 signaling pathway

BACKGROUND

As one of the most classic antineoplastic agents, doxorubicin (Dox) is extensively used to treat a wide range of cancers. Nevertheless, the clinical outcomes of Dox-based therapies are severely hampered due to the significant cardiotoxicity. Glycyrrhetinic acid (GA) is the major biologically active compound of licorice, one of the most well-known food additives and medicinal plants in the world. We previously demonstrated that GA has the potential capability to protect mice from Dox-induced cardiac injuries. However, the underlying cardioprotective mechanism remains unexplored.

PURPOSE

To investigate the cardioprotective benefits of GA against Dox-induced cardiotoxicity and to elucidate its mechanisms of action.

STUDY DESIGN/METHODS

H9c2 cardiomyoblasts and AC16 cardiomyocytes were used as the cell models in vitro. A transgenic zebrafish model and a 4T1 mouse breast cancer model were applied to explore the cardioprotective effects of GA in vivo.

RESULTS

In vitro, GA inhibited Dox-induced cell death and LDH release in H9c2 and AC16 cells without affecting the anti-cancer effects of Dox. GA significantly alleviated Dox-induced ROS generation, mitochondrial dysfunction, and apoptosis in H9c2 cells. Moreover, GA abolished the expression of pro-apoptotic proteins and restored Nrf2/HO-1 signaling pathway in Dox-treated H9c2 cells. On the contrary, Nrf2 knockdown strongly abrogated the cardioprotective effects of GA on Dox-treated H9c2 cells. In vivo, GA attenuated Dox-induced cardiac dysfunction by restoring stroke volume, cardiac output, and fractional shortening in the transgenic zebrafish embryos. In a 4T1 mouse breast cancer model, GA dramatically prevented body weight loss, attenuated cardiac dysfunction, and prolonged survival rate in Dox-treated mice, without compromising Dox's anti-tumor efficacy. Consistently, GA attenuated oxidative injury, reduced cardiomyocytes apoptosis, and restored the expressions of Nrf2 and HO-1 in Dox-treated mouse hearts.

CONCLUSION

GA protects against Dox-induced cardiotoxicity by suppressing oxidative stress, mitochondrial dysfunction, and apoptosis via upregulating Nrf2/HO-1 signaling pathway. These findings could provide solid evidence to support the further development of GA as a feasible and safe adjuvant to Dox chemotherapy for overcoming Dox-induced cardiotoxicity.

N-Tertaining a New Signaling Paradigm for the Cardiomyocyte β 1 -Adrenergic Receptor

ABSTRACT

β 1 -adrenergic receptors (β 1 ARs) are the principle mediators of catecholamine actions in cardiomyocytes. β 1 ARs rapidly adjust cardiac output and provide short-term hemodynamic support for the failing heart by activating a Gs-adenylyl cyclase pathway that increases 3'-5'-cyclic adenosine monophosphate and leads to the activation of protein kinase A and the phosphorylation of substrates involved in excitation-contraction coupling. However, chronic persistent β 1 AR activation in the setting of heart failure leads to a spectrum of maladaptive changes that contribute to the evolution of heart failure. The molecular basis for β 1 AR-driven maladaptive responses remains uncertain because chronic persistent β 1 AR activation has been linked to the activation of both proapoptotic and antiapoptotic signaling pathways. Of note, studies to date have been predicated on the assumption that β 1 ARs signal exclusively as full-length receptor proteins. Our recent studies show that β 1 ARs are detected as both full-length and N-terminally truncated species in cardiomyocytes, that N-terminal cleavage is regulated by O-glycan modifications at specific sites on the β 1 AR N-terminus, and that N-terminally truncated β 1 ARs remain signaling competent, but their signaling properties differ from those of the full-length β 1 AR. The N-terminally truncated form of the β 1 AR constitutively activates the protein kinase B signaling pathway and confers protection against doxorubicin-dependent apoptosis in cardiomyocytes. These studies identify a novel signaling paradigm for the β 1 AR, implicating the N-terminus as a heretofore-unrecognized structural determinant of β 1 AR responsiveness that could be pharmacologically targeted for therapeutic advantage.

Thymoquinone alleviates doxorubicin induced acute kidney injury by decreasing endoplasmic reticulum stress, inflammation and apoptosis

Doxorubicin (DOX) is used as an anticancer drug despite its many side effects. Thymoquinone (THQ) is a plant-derived substance that exhibits antioxidant and anti-inflammatory properties. We investigated the protective effects of THQ on DOX induced nephrotoxicity in rats. Rats were divided into five groups of eight: group 1, untreated control; group 2, olive oil group given olive oil intraperitoneally (i.p.) for 14 days; group 3, THQ group given 10 mg/kg THQ i.p. for 14 days; group 4, DOX group given a single dose of 15 mg/kg DOX i.p. on day 7 of experiment; group 5, DOX + THQ given 10 mg/kg THQ i.p. for 14 days and 15 mg/kg DOX i.p. on day 7. Kidney tissues were evaluated for histopathology. Caspase-3, IL-17, GRP78 and TNF-α immunostaining was used to determine the expression levels of these proteins among the groups. The TUNEL method was used to determine the apoptotic index. Total antioxidant status (TAS), total oxidant status (TOS), and TNF-α and TGF-β1 levels in kidney tissue were measured using ELISA assay. Histopathologic damage, caspase-3, IL-17, GRP78 and TNF-α immunoreactivity, TUNEL positive cells, TOS, TNF-α and TGF-β1 levels were increased in group 4 compared to group 1. The TAS of group 4 decreased compared to group 1. We found decreased caspase-3, IL-17, GRP78 and TNF-α expressions and TUNEL positive cells in group 5 compared to group 4. In rats given DOX, THQ reduced kidney damage by suppressing endoplasmic reticulum stress, inflammation and apoptosis pathways.

Resolvin E1 attenuates doxorubicin-induced cardiac fibroblast senescence: A key role for IL-1β

Cardiac fibroblasts (CFs) undergo senescence in reaction to different stressors, leading to a poor prognosis of cardiac disease. Doxorubicin (Doxo) is an antineoplastic drug with strong cardiotoxic effects, which induces IL-1β secretion and thus, triggers a potent pro-inflammatory response. Doxo induces CFs senescence; however, the mechanisms are not fully understood. Different pharmacological strategies have been used to eliminate senescent cells by inducing their apoptosis or modifying their secretome. However, Resolvin E1 (RvE1), a lipid derivative resolutive mediator with potent anti-inflammatory effects has not been used before to prevent CFs senescence. CFs were isolated from adult male C57BL/6J mice and subsequently stimulated with Doxo, in the presence or absence of RvE1. Senescence-associated β-galactosidase activity (SA-β-gal), γ-H2A.X, p53, p21, and senescence-associated secretory phenotype (SASP) were evaluated. The involvement of the NLRP3 inflammasome/interleukin-1 receptor (IL-1R) signaling pathway on CFs senescence was studied using an NLRP3 inhibitor (MCC950) and an endogenous IL-1R antagonist (IR1A). Doxo is able to trigger CFs senescence, as evidenced by an increase of γ-H2A.X, p53, p21, and SA-β-gal, and changes in the SASP profile. These Doxo effects were prevented by RvE1. Doxo triggers IL-1β secretion, which was dependent on NLRP3 activation. Doxo-induced CFs senescence was partially blocked by MCC950 and IR1A. In addition, IL-1β also triggered CFs senescence, as evidenced by the increase of γ-H2A.X, p53, p21, SA-β-gal activity, and SASP. All these effects were also prevented by RvE1 treatment. CONCLUSION: These data show the anti-senescent role of RvE1 in Doxo-induced CFs senescence, which could be mediated by reducing IL-1β secretion.

A circular RNA derived from the insulin receptor locus protects against doxorubicin-induced cardiotoxicity

AIMS

Cardiotoxicity leading to heart failure (HF) is a growing problem in many cancer survivors. As specific treatment strategies are not available, RNA discovery pipelines were employed and a new and powerful circular RNA (circRNA)-based therapy was developed for the treatment of doxorubicin-induced HF.

METHODS AND RESULTS

The circRNA sequencing was applied and the highly species-conserved circRNA insulin receptor (Circ-INSR) was identified, which participates in HF processes, including those provoked by cardiotoxic anti-cancer treatments. Chemotherapy-provoked cardiotoxicity leads to the down-regulation of Circ-INSR in rodents and patients, which mechanistically contributes to cardiomyocyte cell death, cardiac dysfunction, and mitochondrial damage. In contrast, Circ-INSR overexpression prevented doxorubicin-mediated cardiotoxicity in both rodent and human cardiomyocytes in vitro and in a mouse model of chronic doxorubicin cardiotoxicity. Breast cancer type 1 susceptibility protein (Brca1) was identified as a regulator of Circ-INSR expression. Detailed transcriptomic and proteomic analyses revealed that Circ-INSR regulates apoptotic and metabolic pathways in cardiomyocytes. Circ-INSR physically interacts with the single-stranded DNA-binding protein (SSBP1) mediating its cardioprotective effects under doxorubicin stress. Importantly, in vitro transcribed and circularized Circ-INSR mimics also protected against doxorubicin-induced cardiotoxicity.

CONCLUSION

Circ-INSR is a highly conserved non-coding RNA which is down-regulated during cardiotoxicity and cardiac remodelling. Adeno-associated virus and circRNA mimics-based Circ-INSR overexpression prevent and reverse doxorubicin-mediated cardiomyocyte death and improve cardiac function. The results of this study highlight a novel and translationally important Circ-INSR-based therapeutic approach for doxorubicin-induced cardiac dysfunction.

Risk Factors for Anthracycline-Induced Cardiotoxicity in Breast Cancer Treatment: A Meta-Analysis

Background

Anthracyclines play an important role in the treatment of breast cancer (BC) and other malignant tumors. However, accompanied side-effects are non-ignorable. The purpose of this meta-analysis is to determine the risk factors for anthracycline-induced cardiotoxicity (ACT), so as to identify high-risk patients.

Methods

The search for literature was conducted in PubMed, The Cochrane Library, Embase and Web of science. Records were selected with inclusion criteria and exclusion criteria. The newcastle-ottawa scale (NOS) was used to assess the quality of literature, and Review Manager 5.3 software was used for meta-analysis.

Results

Thirteen studies met the inclusion criteria. Meta-analysis indicated that risk factors for ACT were use of trastuzumab (odds ratio [OR]: 2.84, 95% confidence interval [CI]: 2.49-3.22, p < 0.00001), cumulative dose of anthracyclines (OR: 1.45, 95%CI: 1.28-1.65, p < 0.00001), hypertension (OR: 2.95, 95%CI: 1.75-4.97, p < 0.0001), diabetes mellitus (DM) (OR: 1.39, 95%CI: 1.20-1.61, p < 0.0001), tumor metastasis (OR: 1.91, 95%CI: 1.17-3.11, p = 0.009) and coronary heart disease (CAD) (OR: 2.17, 95%CI: 1.50-3.15, p < 0.0001). In addition, our analysis revealed that body mass index (BMI) had no effect on ACT (OR: 1.18, 95%CI: 0.98-1.43, p = 0.08).

Conclusions

Patients with high risk for ACT can be identified by these factors. For such patients, a higher level of monitoring and protection for the cardiac function should be performed by clinicians.

Systematic Review Registration

INPLASY, identifier INPLASY202250140.

Exercise Cardio-Oncology: Exercise as a Potential Therapeutic Modality in the Management of Anthracycline-Induced Cardiotoxicity

Anthracyclines are one of the most effective chemotherapy agents and have revolutionized cancer therapy. However, anthracyclines can induce cardiac injuries through ‘multiple-hits', a series of cardiovascular insults coupled with lifestyle risk factors, which increase the risk of developing short- and long-term cardiac dysfunction and cardiovascular disease that potentially lead to premature mortality following cancer remission. Therefore, the management of anthracycline-induced cardiotoxicity is a serious unmet clinical need. Exercise therapy, as a non-pharmacological intervention, stimulates numerous biochemical and physiologic adaptations, including cardioprotective effects, through the cardiovascular system and cardiac muscles, where exercise has been proposed to be an effective clinical approach that can protect or reverse the cardiotoxicity from anthracyclines. Many preclinical and clinical trials demonstrate the potential impacts of exercise on cardiotoxicity; however, the underlying mechanisms as well as how to implement exercise in clinical settings to improve or protect against long-term cardiovascular disease outcomes are not clearly defined. In this review, we summarize the current evidence in the field of “exercise cardio-oncology” and emphasize the utilization of exercise to prevent and manage anthracycline-induced cardiotoxicities across high-risk and vulnerable populations diagnosed with cancer.

Sodium-Glucose Cotransporter 2 Inhibitors and Heart Failure: A Bedside-to-Bench Journey

Type 2 diabetes mellitus (T2DM) and heart failure (HF) are multifactorial diseases sharing common risk factors, such as obesity, hyperinsulinemia, and inflammation, with underlying mechanisms including endothelial dysfunction, inflammation, oxidative stress, and metabolic alterations. Cardiovascular benefits of sodium-glucose cotransporter 2 (SGLT2) inhibitors observed in diabetic and non-diabetic patients are also related to their cardiac-specific, SGLT-independent mechanisms, in addition to the metabolic and hemodynamic effects. In search of the possible underlying mechanisms, a research campaign has been launched proposing varied mechanisms of action that include intracellular ion homeostasis, autophagy, cell death, and inflammatory processes. Moreover, the research focus was widened toward cellular targets other than cardiomyocytes. At the moment, intracellular sodium level reduction is the most explored mechanism of direct cardiac effects of SGLT2 inhibitors that mediate the benefits in heart failure in addition to glucose excretion and diuresis. The restoration of cardiac Na⁺ levels with consequent positive effects on Ca²⁺ handling can directly translate into improved contractility and relaxation of cardiomyocytes and have antiarrhythmic effects. In this review, we summarize clinical trials, studies on human cells, and animal models, that provide a vast array of data in support of repurposing this class of antidiabetic drugs.

Transient Exposure of Endothelial Cells to Doxorubicin Leads to Long-Lasting Vascular Endothelial Growth Factor Receptor 2 Downregulation

Doxorubicin (Dox) is an effective antineoplastic drug with serious cardiotoxic side effects that persist after drug withdrawal and can lead to heart failure. Dysregulation of vascular endothelium has been linked to the development of Dox-induced cardiotoxicity, but it is unclear whether and how transient exposure to Dox leads to long-term downregulation of Endothelial Vascular Endothelial Growth Factor Receptor type2 (VEGFR2), essential for endothelial cells function. Using an in vitro model devised to study the long-lasting effects of brief endothelial cells exposure to Dox, we show that Dox leads to sustained protein synthesis inhibition and VEGFR2 downregulation. Transient Dox treatment led to the development of long-term senescence associated with a reduction in VEGFR2 levels that persisted days after drug withdrawal. By analyzing VEGFR2 turnover, we ruled out that its downregulation was depended on Dox-induced autophagy. Conversely, Dox induced p53 expression, reduced mTOR-dependent translation, and inhibited global protein synthesis. Our data contribute to a mechanistic basis to the permanent damage caused to endothelial cells by short-term Dox treatment.

Mitochondrial Dynamin-Related Protein Drp1: a New Player in Cardio-oncology

PURPOSE OF REVIEW

This study is aimed at reviewing the recent progress in Drp1 inhibition as a novel approach for reducing doxorubicin-induced cardiotoxicity and for improving cancer treatment.

RECENT FINDINGS

Anthracyclines (e.g. doxorubicin) are one of the most common and effective chemotherapeutic agents to treat a variety of cancers. However, the clinical usage of doxorubicin has been hampered by its severe cardiotoxic side effects leading to heart failure. Mitochondrial dysfunction is one of the major aetiologies of doxorubicin-induced cardiotoxicity. The morphology of mitochondria is highly dynamic, governed by two opposing processes known as fusion and fission, collectively known as mitochondrial dynamics. An imbalance in mitochondrial dynamics is often reported in tumourigenesis which can lead to adaptive and acquired resistance to chemotherapy. Drp1 is a key mitochondrial fission regulator, and emerging evidence has demonstrated that Drp1-mediated mitochondrial fission is upregulated in both cancer cells to their survival advantage and injured heart tissue in the setting of doxorubicin-induced cardiotoxicity. Effective treatment to prevent and mitigate doxorubicin-induced cardiotoxicity is currently not available. Recent advances in cardio-oncology have highlighted that Drp1 inhibition holds great potential as a targeted mitochondrial therapy for doxorubicin-induced cardiotoxicity.

PEGylated Liposomes Remotely Loaded with the Combination of Doxorubicin, Quinine, and Indocyanine Green Enable Successful Treatment of Multidrug-Resistant Tumors

Multidrug resistance (MDR) of cancer cells remains a major obstacle to favorable outcomes of treatment with many drugs, including doxorubicin. Most of the clinical trials failed to demonstrate the benefit of the drug efflux transporter P-glycoprotein (P-gp) inhibitors to circumvent P-gp-mediated drug resistance in vivo. The present study explored the therapeutic potential of combined treatment with liposomal doxorubicin, P-gp inhibitor quinine, and the photodynamic therapy (PDT) using indocyanine green (ICG) in the adenocarcinoma drug-resistant tumor model. Liposomes were actively co-remotely loaded with doxorubicin and quinine, and ICG was passively adsorbed. The liposomes were characterized by differential scanning calorimetry (DSC) and cryogenic transmission microscopy (Cryo-TEM). We found that quinine impaired the crystalline structure of doxorubicin. In vitro, treatment with single agents themselves was insufficient to inhibit the growth of HT-29 MDR1 cells. However, pegylated liposomal doxorubicin and quinine (PLDQ) significantly diminished HT-29 MDR1 cell survival. Furthermore, survival inhibition intensified by the addition of ICG to the PLDQ (ICG + PLDQ). In vivo, ICG + PLDQ significantly decreased tumor growth when combined with tumor irradiation with NIR light (** p < 0.01). ICG + PLDQ + irradiation was superior to single treatments or combinational treatments without irradiation. These findings suggest that ICG + PLDQ can overcome P-gp-mediated MDR in cancer cells.

Nucleus-mitochondria positive feedback loop formed by ERK5 S496 phosphorylation-mediated poly (ADP-ribose) polymerase activation provokes persistent pro-inflammatory senescent phenotype and accelerates coronary atherosclerosis after chemo-radiation

The incidence of cardiovascular disease (CVD) is higher in cancer survivors than in the general population. Several cancer treatments are recognized as risk factors for CVD, but specific therapies are unavailable. Many cancer treatments activate shared signaling events, which reprogram myeloid cells (MCs) towards persistent senescence-associated secretory phenotype (SASP) and consequently CVD, but the exact mechanisms remain unclear. This study aimed to provide mechanistic insights and potential treatments by investigating how chemo-radiation can induce persistent SASP. We generated ERK5 S496A knock-in mice and determined SASP in myeloid cells (MCs) by evaluating their efferocytotic ability, antioxidation-related molecule expression, telomere length, and inflammatory gene expression. Candidate SASP inducers were identified by high-throughput screening, using the ERK5 transcriptional activity reporter cell system. Various chemotherapy agents and ionizing radiation (IR) up-regulated p90RSK-mediated ERK5 S496 phosphorylation. Doxorubicin and IR caused metabolic changes with nicotinamide adenine dinucleotide depletion and ensuing mitochondrial stunning (reversible mitochondria dysfunction without showing any cell death under ATP depletion) via p90RSK-ERK5 modulation and poly (ADP-ribose) polymerase (PARP) activation, which formed a nucleus-mitochondria positive feedback loop. This feedback loop reprogramed MCs to induce a sustained SASP state, and ultimately primed MCs to be more sensitive to reactive oxygen species. This priming was also detected in circulating monocytes from cancer patients after IR. When PARP activity was transiently inhibited at the time of IR, mitochondrial stunning, priming, macrophage infiltration, and coronary atherosclerosis were all eradicated. The p90RSK-ERK5 module plays a crucial role in SASP-mediated mitochondrial stunning via regulating PARP activation. Our data show for the first time that the nucleus-mitochondria positive feedback loop formed by p90RSK-ERK5 S496 phosphorylation-mediated PARP activation plays a crucial role of persistent SASP state, and also provide preclinical evidence supporting that transient inhibition of PARP activation only at the time of radiation therapy can prevent future CVD in cancer survivors.

Irisin ameliorates doxorubicin-induced cardiac perivascular fibrosis through inhibiting endothelial-to-mesenchymal transition by regulating ROS accumulation and autophagy disorder in endothelial cells

The dose-dependent toxicity to cardiomyocytes has been well recognized as a central characteristic of doxorubicin (DOX)-induced cardiotoxicity (DIC), however, the pathogenesis of DIC in the cardiac microenvironment remains elusive. Irisin is a new hormone-like myokine released into the circulation in response to exercise with distinct functions in regulating apoptosis, inflammation, and oxidative stress. Recent advances revealed the role of irisin as a novel therapeutic method and an important mediator of the beneficial effects of exercise in cardioprotection. Here, by using a low-dose long-term mouse DIC model, we found that the perivascular fibrosis was involved in its myocardial toxicity with the underlying mechanism of endothelial-to-mesenchymal transition (EndMT). Irisin treatment could partially reverse DOX-induced perivascular fibrosis and cardiotoxicity compared to endurance exercise. Mechanistically, DOX stimulation led to excessive accumulation of ROS, which activated the NF-κB-Snail pathway and resulted in EndMT. Besides, dysregulation of autophagy was also found in DOX-treated endothelial cells. Restoring autophagy flux could ameliorate EndMT and eliminate ROS. Irisin treatment significantly alleviated ROS accumulation, autophagy disorder, NF-κB-Snail pathway activation as well as the phenotype of EndMT by targeting uncoupling protein 2 (UCP2). Our results also initially found that irisin was mainly secreted by cardiomyocytes in the cardiac microenvironment, which was significantly reduced by DOX intervention, and had a protective effect on endothelial cells in a paracrine manner. In summary, our study indicated that DOX-induced ROS accumulation and autophagy disorders caused an EndMT in CMECs, which played a role in the perivascular fibrosis of DIC. Irisin treatment could partially reverse this phenomenon by regulating UCP2. Cardiomyocytes were the main source of irisin in the cardiac microenvironment. The current study provides a novel perspective elucidating the pathogenesis and the potential treatment of DIC.

Comparative Study of the Pharmacological Properties and Biological Effects of Polygonum aviculare L. herba Extract-Entrapped Liposomes versus Quercetin-Entrapped Liposomes on Doxorubicin-Induced Toxicity on HUVECs

This study aimed to evaluate the comparative biological effects of Polygonum aviculare L. herba (PAH) extract and quercetin-entrapped liposomes on doxorubicin (Doxo)-induced toxicity in HUVECs. HUVECs were treated with two formulations of liposomes loaded with PAH extract (L5 and L6) and two formulations of liposomes loaded with quercetin (L3 prepared with phosphatidylcholine and L4 prepared with phosphatidylserine). The results obtained with atomic force microscopy, zeta potential and entrapment liposome efficiency confirmed the interactions of the liposomes with PAH or free quercetin and a controlled release of flavonoids entrapped in all the liposomes. Doxo decreased the cell viability and induced oxidative stress, inflammation, DNA lesions and apoptosis in parallel with the activation of Nrf2 and NF-kB. Free quercetin, L3 and L4 inhibited the oxidative stress and inflammation and reduced apoptosis, particularly L3. Additionally, these compounds diminished the Nrf2 and NF-kB expressions and DNA lesions, principally L4. PAH extract, L5 and L6 exerted antioxidant and anti-inflammatory activities, reduced γH2AX formation and inhibited extrinsic apoptosis and transcription factors activation but to a lesser extent. The loading of quercetin in liposomes increased the cell viability and exerted better endothelial protection compared to free quercetin, especially L3. The liposomes with PAH extract had moderate efficiency, mainly due to the antioxidant and anti-inflammatory effects and the inhibition of extrinsic apoptosis.

Inhibition of the DSB repair protein RAD51 potentiates the cytotoxic efficacy of doxorubicin via promoting apoptosis-related death pathways

The anthracycline derivative doxorubicin (Doxo) induces DNA double-strand breaks (DSBs) by inhibition of DNA topoisomerase type II. Defective mismatch repair (MMR) contributes to Doxo resistance and has been reported for colon and mammary carcinomas. Here, we investigated the outcome of pharmacological inhibition of various DNA repair-related mechanisms on Doxo-induced cytotoxicity employing MMR-deficient HCT-116 colon carcinoma cells. Out of different inhibitors tested (i.e. HDACi, PARPi, MRE11i, RAD52i, RAD51i), we identified the RAD51-inhibitor B02 as the most powerful compound to synergistically increase Doxo-induced cytotoxicity. B02-mediated synergism rests on pleiotropic mechanisms, including pronounced G2/M arrest, damage to mitochondria and caspase-driven apoptosis. Of note, B02 also promotes the cytotoxicity of oxaliplatin and 5-fluoruracil (5-FU) in HCT-116 cells and, furthermore, also increases Doxo-induced cytotoxicity in MMR-proficient colon and mammary carcinoma cells. Summarizing, pharmacological inhibition of RAD51 is suggested to synergistically increase the cytotoxic efficacy of various types of conventional anticancer drugs in different tumor entities. Hence, pre-clinical in vivo studies are preferable to determine the therapeutic window of B02 in a clinically oriented therapeutic regimen.

Vitamin D3 attenuates doxorubicin-induced senescence of human aortic endothelial cells by upregulation of IL-10 via the pAMPKα/Sirt1/Foxo3a signaling pathway

The toxicity of doxorubicin to the cardiovascular system often limits its benefits and widespread use as chemotherapy. The mechanisms involved in doxorubicin-induced cardiovascular damage and possible protective interventions are not well-explored. Using human aortic endothelial cells, we show vitamin D3 strongly attenuates doxorubicin-induced senescence and cell cycle arrest. We further show the protective effects of vitamin D3 are mediated by the upregulation of IL-10 and FOXO3a expression through fine modulation of pAMPKα/SIRT1/FOXO3a complex activity. These results have great significance in finding a target for mitigating doxorubicin-induced cardiovascular toxicity.

Analysis of Models of Doxorubicin-Induced Cardiomyopathy in Rats and Mice. A Modern View From the Perspective of the Pathophysiologist and the Clinician

Today the pharmacological possibilities of treating cancer are expanding and as a result, life expectancy is increasing against the background of chemotherapy and supportive treatment. In the conditions of successful antitumor treatment, complications associated with its toxic effect on healthy tissues and organs began to come to the fore. Anthracycline cardiomyopathy was the first serious cardiovascular complication to draw the attention of oncologists and cardiologists around the world. Anthracycline drugs such as doxorubicin, epirubicin, idarubicin are still widely used in oncological practice to treat a wide range of solid and hematological malignancies. Doxorubicin-induced cardiomyopathy is closely associated with an increase in oxidative stress, as evidenced by reactive oxygen species (ROS) nduced damage such as lipid peroxidation, and decreased levels of antioxidants. Myofibrillar destruction and dysregulation of intracellular calcium are also important mechanisms, usually associated with doxorubicin-induced cardiotoxicity. Despite the abundance of data on various mechanisms involved in the implementation of doxorubicin-induced cardiotoxicity, a final understanding of the mechanism of the development of doxorubicin cardiomyopathy has not yet been formed. It poses the most significant challenges to the development of new methods of prevention and treatment, as well as to the unambiguous choice of a specific treatment regimen using the existing pharmacological tools. In order to resolve these issues new models that could reflect the development of the chemotherapy drugs effects are needed. In this review we have summarized and analyzed information on the main existing models of doxorubicin cardiomyopathy using small laboratory animals. In addition, this paper discusses further areas of research devoted to the development and validation of new improved models of doxorubicin cardiomyopathy suitable both for studying the mechanisms of its implementation and for the preclinical drugs effectiveness assessment.