The flavonoid quercetin: possible solution for anthracycline-induced cardiotoxicity and multidrug resistance

Can Dietary Nutrients Prevent Cancer Chemotherapy-Induced Cardiotoxicity? An Evidence Mapping of Human Studies and Animal Models

Introduction

Chemotherapy has significantly improved cancer survival rates at the cost of irreversible and frequent cardiovascular toxicity. As the main dose-dependent adverse effect, cardiotoxic effects not only limit the usage of chemotherapeutic agents, but also cause the high risk of severe poor prognoses for cancer survivors. Therefore, it is of great significance to seek more effective cardioprotective strategies. Some nutrients have been reported to diminish cardiac oxidative damage associated with chemotherapy. However, the currently available evidence is unclear, which requires a rigorous summary. As such, we conducted a systematic review of all available evidence and demonstrated whether nutrients derived from food could prevent cardiotoxicity caused by chemotherapy.

Methods

We searched Medline (via PubMed), Embase and the Cochrane Library from inception to Nov 9, 2021 to identify studies reporting dietary nutrients against cancer chemotherapy-related cardiotoxicity. We performed descriptive summaries on the included studies, and used forest plots to demonstrate the effects of various dietary nutrients.

Results

Fifty-seven eligible studies were identified, involving 53 animal studies carried on rats or mice and four human studies in cancer patients. Seven types of dietary nutrients were recognized including polyphenols (mainly extracted from grapes, grape seeds, and tea), allicin (mainly extracted form garlic), lycopene (mainly extracted from tomatoes), polyunsaturated fatty acids, amino acids (mainly referring to glutamine), coenzyme Q10, and trace elements (mainly referring to zinc and selenium). Dietary nutrients ameliorated left ventricular dysfunctions and myocardial oxidative stress at varying degrees, which were caused by chemotherapy. The overall risk of bias of included studies was at moderate to high risk.

Conclusion

The results indicated that dietary nutrients might be a potential strategy to protect cardiovascular system exposed to the chemotherapeutic agents, but more human studies are urged in this field.Systematic Review Registration: https://inplasy.com/inplasy-2022-3-0015/.

Serine mutations in overexpressed Hsp27 abrogate the protection against doxorubicin-induced p53-dependent cardiac apoptosis in mice

Small heat shock proteins (sHsps) protect the heart from chemotherapeutics-induced heart failure by inhibiting p53-dependent apoptosis. However, mechanism of such protection has not been elucidated yet. Here we test a hypothesis that serine phosphorylation of sHsps is essential to inhibit the doxorubicin-induced and p53-dependent apoptotic pathway. Three transgenic mice (TG) lines with cardiomyocyte-specific overexpression of human heat shock protein 27 (hHsp27), namely, wild-type [myosin heavy chain (MHC)-hHsp27], S82A single mutant [MHC-mut-hHsp27(S82A)], and trimutant [MHC-mut-hHsp27(S15A/S78A/S82A)] were generated. TG mice were treated with Dox (6 mg/kg body wt; once in a week; 4 wk) along with age-matched nontransgenic (non-TG) controls. The Dox-treated MHC-hHsp27 mice showed improved survival and cardiac function (both MRI and echocardiography) in terms of contractility [ejection fraction (%EF)] and left ventricular inner diameter (LVID) compared with the Dox-treated non-TG mice. However, both MHC-mut-hHsp27(S82A) and MHC-mut-hHsp27(S15A/S78A/S82A) mutants overexpressing TG mice did not show such a cardioprotection. Furthermore, transactivation of p53 was found to be attenuated only in Dox-treated MHC-hHsp27 mice-derived cardiomyocytes in vitro, as low p53 was detected in the nuclei, not in mutant hHsp27 overexpressing cardiomyocytes. Similarly, only in MHC-hHsp27 overexpressing cardiomyocytes, low Bax, higher mechanistic target of rapamycin (mTOR) phosphorylation, and low apoptotic poly(ADP-ribose) polymerase-1 (PARP-1) cleavage (89 kDa fragment) were detected. Pharmacological inhibition of p53 was more effective in mutant TG mice compared with MHC-hHsp27 mice. We conclude that phosphorylation of overexpressed Hsp27 at S82 and its association with p53 are essential for the cardioprotective effect of overexpressed Hsp27 against Dox-induced dilated cardiomyopathy. Only phosphorylated Hsp27 protects the heart by inhibiting p53 transactivation.NEW & NOTEWORTHY Requirement of serine phosphorylation in Hsp27 for cardioprotective effect against Dox is tested in various mutants overexpressing mice. Cardioprotective effect was found to be compromised in Hsp27 serine mutants overexpressed mice compared with wild-type overexpressing mice. These results indicate that cancer patients, who carry these mutations, may have higher risk of aggravated cardiomyopathy on treated with cardiotoxic chemotherapeutics such as doxorubicin.

Reactive Oxygen Species and Their Involvement in Red Blood Cell Damage in Chronic Kidney Disease

Reactive oxygen species (ROS) released in cells are signaling molecules but can also modify signaling proteins. Red blood cells perform a major role in maintaining the balance of the redox in the blood. The main cytosolic protein of RBC is hemoglobin (Hb), which accounts for 95-97%. Most other proteins are involved in protecting the blood cell from oxidative stress. Hemoglobin is a major factor in initiating oxidative stress within the erythrocyte. RBCs can also be damaged by exogenous oxidants. Hb autoxidation leads to the generation of a superoxide radical, of which the catalyzed or spontaneous dismutation produces hydrogen peroxide. Both oxidants induce hemichrome formation, heme degradation, and release of free iron which is a catalyst for free radical reactions. To maintain the redox balance, appropriate antioxidants are present in the cytosol, such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and peroxiredoxin 2 (PRDX2), as well as low molecular weight antioxidants: glutathione, ascorbic acid, lipoic acid, α-tocopherol, β-carotene, and others. Redox imbalance leads to oxidative stress and may be associated with overproduction of ROS and/or insufficient capacity of the antioxidant system. Oxidative stress performs a key role in CKD as evidenced by the high level of markers associated with oxidative damage to proteins, lipids, and DNA in vivo. In addition to the overproduction of ROS, a reduced antioxidant capacity is observed, associated with a decrease in the activity of SOD, GPx, PRDX2, and low molecular weight antioxidants. In addition, hemodialysis is accompanied by oxidative stress in which low-biocompatibility dialysis membranes activate phagocytic cells, especially neutrophils and monocytes, leading to a respiratory burst. This review shows the production of ROS under normal conditions and CKD and its impact on disease progression. Oxidative damage to red blood cells (RBCs) in CKD and their contribution to cardiovascular disease are also discussed.

Protection against chemotherapy- and radiotherapy-induced side effects: A review based on the mechanisms and therapeutic opportunities of phytochemicals

BACKGROUND

Although great achievements have been made in the field of cancer therapy, chemotherapy and radiotherapy remain the mainstay cancer therapeutic modalities. However, they are associated with various side effects, including cardiocytotoxicity, nephrotoxicity, myelosuppression, neurotoxicity, hepatotoxicity, gastrointestinal toxicity, mucositis, and alopecia, which severely affect the quality of life of cancer patients. Plants harbor a great chemical diversity and flexible biological properties that are well-compatible with their use as adjuvant therapy in reducing the side effects of cancer therapy.

PURPOSE

This review aimed to comprehensively summarize the molecular mechanisms by which phytochemicals ameliorate the side effects of cancer therapies and their potential clinical applications.

METHODS

We obtained information from PubMed, Science Direct, Web of Science, and Google scholar, and introduced the molecular mechanisms by which chemotherapeutic drugs and irradiation induce toxic side effects. Accordingly, we summarized the underlying mechanisms of representative phytochemicals in reducing these side effects.

RESULTS

Representative phytochemicals exhibit a great potential in reducing the side effects of chemotherapy and radiotherapy due to their broad range of biological activities, including antioxidation, antimutagenesis, anti-inflammation, myeloprotection, and immunomodulation. However, since a majority of the phytochemicals have only been subjected to preclinical studies, clinical trials are imperative to comprehensively evaluate their therapeutic values.

CONCLUSION

This review highlights that phytochemicals have interesting properties in relieving the side effects of chemotherapy and radiotherapy. Future studies are required to explore the clinical benefits of these phytochemicals for exploitation in chemotherapy and radiotherapy.

Molecular and Biological Functions of Quercetin as a Natural Solution for Cardiovascular Disease Prevention and Treatment

Cardiovascular disease (CVD) is a worldwide health problem with growing up rates of mortality and morbidity. Many risk factors, including high blood pressure, cigarette smoking, diabetes, obesity, and dyslipidemia are responsible for CVD. CVD can be prevented by some simple and cost-effective steps such as smoking cessation, normalizing body weight, regular physical activity, and dietary changes, including decreasing saturated fats, increasing the intake of vegetables and fruits, and reducing sugar intake. In the last decades, growing up number of studies were performed to explain the possible function of non-nutrient substances from the diet which might prevent CVD. One of these natural compounds is quercetin which is widely present in vegetables, tea, fruits and wine. Many in vitro, in vivo and clinical studies have indicated the cardioprotective functions of quercetin. They can be explained by quercetin's reducing blood pressure, antioxidant potential and some other activities. This review evaluates the experimental and clinical studies that have studied the effect of quercetin in CVD and summarizes the molecular mechanisms of action as well as clinical effects of quercetin in CVD.

Combination Therapy of Doxorubicin and Quercetin on Multidrug-Resistant Breast Cancer and Their Sequential Delivery by Reduction-Sensitive Hyaluronic Acid-Based Conjugate/d-α-Tocopheryl Poly(ethylene glycol) 1000 Succinate Mixed Micelles

The therapeutic efficacy of chemotherapy in many types of hematological malignancies and solid tumors is dramatically hindered by multidrug resistance (MDR). This work presents a combination strategy of pretreatment of MDA-MB-231/MDR1 cells with quercetin (QU) followed by doxorubicin (DOX) to overcome MDR, which can be delivered by mixed micelles composed of the reduction-sensitive hyaluronic acid-based conjugate and d-α-tocopheryl poly(ethylene glycol) 1000 succinate. The combination strategy can enhance the cytotoxicity of DOX on MDA-MB-231/MDR1 cells by increasing intracellular DOX accumulation and facilitating DOX-induced apoptosis. The probable MDR reversal mechanisms are that the pretreatment cells with QU-loaded mixed micelles downregulate P-glycoprotein expression to decrease DOX efflux as well as initiate mitochondria-dependent apoptotic pathways to accelerate DOX-induced apoptosis. In addition, this combination strategy can not only potentiate in vivo tumor-targeting efficiency but also enhance the antitumor effect in MDA-MB-231/MDR1-bearing nude mice without toxicity or side effects. This research suggests that the co-administration of natural compounds and chemotherapeutic drugs could be an effective strategy to overcome tumor MDR, which deserves further exploration.

Therapeutic potential of natural compounds in inflammation and chronic venous insufficiency

The term varicose vein refers to the twisted and swollen vein visible under the skin surface which occurs most commonly in the leg. Epidemiological studies report a varying percentage of incidences from 2 to 56% in men and <1-60% in women. Venous insufficiency is most often caused by the damage to the valves and walls of the veins. The mechanism of varicose vein formation is complex. It is, however, based on hypotensive blood vessels, hypoxia, and other mechanisms associated with inflammation. This work describes mechanisms related to the formation and development of the varicose vein. It discusses risk factors, pathogenesis of chronic venous disease, markers of the epithelial and leukocyte activation, state of hypoxia and inflammation, reactive oxygen species (ROS) generation, and oxidative stress. Additionally, this paper describes substances of plant origin used in the treatment of venous insufficiency. It also considers the structure of the molecules, their properties, and their mechanisms of action, the structure-activity relationship and chemical properties of flavonoids and other substances. The flavonoids include quercetin derivatives, micronized purified flavonoid fraction (Daflon), natural pine bark extract (Pycnogenol), and others such as triterpene saponine, extracts from Ruscus aculeatus and Centella asiatica, Ginkgo biloba extract, coumarin dereivatives that are used in chronic venous insufficiency. Flavonoids are natural substances found in plants, including fruits, vegetables, flowers, and others. They are important to the circulatory system and critical to blood vessels and the blood flow. Additionally, they have antioxidant, antiinflammatory properties.

Glabridin resensitizes p-glycoprotein-overexpressing multidrug-resistant cancer cells to conventional chemotherapeutic agents

Multidrug resistance (MDR) remains an obstacle to chemotherapy related with the overexpression of several efflux membrane proteins, and p-glycoprotein (P-gp) is the most studied among them. Thus, continuous investigational efforts are necessary to find valuable MDR reversal agents, and the flavonoid compound glabridin (GBD) seems to be a promising candidate. This study aimed to investigate the potential of GBD against MDR and explore the possible mechanisms. First, we found that GBD could decrease the half maximal inhibitory concentration of paclitaxel and doxorubicin (DOX) in breast cancer cells like MDA-MB-231/MDR1 cells and MCF-7/ADR cells. It was further explained that GBD enhanced the apoptosis of MDA-MB-231/MDR1 cells induced by DOX, due to the increased accumulation of DOX. Then, tests were performed to explore the possible MDR reversal mechanisms. On one hand, GBD can suppress the expression of P-gp. On the other hand, GBD can downregulate the activity of P-gp ATPase when cotreated with DOX or verapamil, revealing that GBD was a substrate of P-gp. Moreover, the obtained kinetic inhibition parameters proved that GBD was a competitive inhibitor of P-gp, and in molecular docking simulation modeling, GBD exhibited stronger binding affinity with P-gp than DOX. In conclusion, GBD can increase the accumulation of DOX in MDA-MB-231/MDR1 cells by suppressing the expression of P-gp and competitively inhibiting the P-gp efflux pump and enhance the apoptosis of MDA-MB-231/MDR1 cells induced by DOX, and thus realize reversal effects on MDR. Therefore, the combination therapy of anticancer drugs and flavonoid-like GBD is a promising strategy to overcome P-gp-mediated MDR.

Quercetin and doxorubicin co-encapsulated biotin receptor-targeting nanoparticles for minimizing drug resistance in breast cancer

The combination of a chemotherapeutic drug with a chemosensitizer has emerged as a promising strategy for cancers showing multidrug resistance (MDR). Herein we describe the simultaneous targeted delivery of two drugs to tumor cells by using biotin-decorated poly(ethylene glycol)-b-poly(ε-caprolactone) nanoparticles encapsulating the chemotherapeutic drug doxorubicin and the chemosensitizer quercetin (BNDQ). Next, the potential ability of BNDQ to reverse MDR in vitro and in vivo was investigated. Studies demonstrated that BNDQ was more effectively taken up with less efflux by doxorubicin-resistant MCF-7 breast cancer cells (MCF-7/ADR cells) than by the cells treated with the free drugs, single-drug–loaded nanoparticles, or non-biotin–decorated nanoparticles. BNDQ exhibited clear inhibition of both the activity and expression of P-glycoprotein in MCF-7/ADR cells. More importantly, it caused a significant reduction in doxorubicin resistance in MCF-7/ADR breast cancer cells both in vitro and in vivo, among all the groups. Overall, this study suggests that BNDQ has a potential role in the treatment of drug-resistant breast cancer.

Differential toxicity of gold-doxorubicin in cancer cells vs. cardiomyocytes as measured by real-time growth assays and fluorescence lifetime imaging microscopy (FLIM)

The kinetics of toxicity of doxorubicin (Dox) and gold nanoparticle-conjugated doxorubicin (Au-Dox) were investigated in cultured B16 melanoma cells and cardiomyocytes using real-time cell-growth imaging. Both bolus exposure and continuous exposure were used. Modeling of the growth curve dynamics suggested patterns of uptake and/or expulsion of the drug that were different for the different cell lines and exposures. Dox alone in B16 cells fit to a model of slow drug buildup, whereas Au-Dox fit to a pattern of initial high drug efficacy followed by a decrease. In cardiomyocytes, the best fit was to a model of increasing drug concentration which then began to decrease, consistent with breakdown of the doxorubicin in solution. Cardiomyocytes were more sensitive than B16 cells to Dox alone (IC50 123 ± 2 nM vs. 270 ± 2 nM with continuous exposure), but were dramatically less sensitive to Au-Dox (IC50 1 ± 0.1 μM vs. 58 ± 5 nM with continuous exposure). Bolus exposure for 40 min led to significant cell death in B16 cells but not in cardiomyocytes. Fluorescence lifetime imaging (FLIM) showed different patterns of uptake of Au-Dox in the two cell types that explained the differential toxicity. While Au-Dox concentrated in the nuclei of B16 cells, it remained endosomal in cardiomyocytes. These results suggest that stable conjugates of nanoparticles to doxorubicin may be useful for treating resistant cancers while sparing healthy tissue.