Control of doxorubicin-induced, reactive oxygen-related apoptosis by glutathione peroxidase 1 in cardiac fibroblasts

The cardioprotective properties of Persicaria maculosa and Citrus sinensis extracts against doxorubicin-induced cardiotoxicity in mice

Objective

This study assessed the cardioprotective properties of Persicaria maculosa (PME) and Citrus sinensis (CME) hydro-methanolic extracts, besides Citrus sinensis aqueous extract (CWE) against doxorubicin (DOX)-induced cardiotoxicity.

Materials and Methods

The extracts were characterized. Mice were divided into eight groups: control (saline), DOX, protected (injected with 200 mg/kg of PME, CWE or CME for 21 days, orally, and DOX), and extracts (PME, CWE or CME administration, orally, for 21 days). DOX was injected (5 mg/kg, ip) on days 8, 13 and 18 of the experiment. Cardiac tumor necrosis factor-alpha (TNF-α), nuclear factor (erythroid-derived 2)-like 2 (Nrf2) and carbonyl reductase 1 (CBR1) expression levels, besides superoxide dismutase, catalase, malondialdehyde, nitric oxide and total protein levels were evaluated. Serum lactate dehydrogenase, creatine phosphokinase cardiac isoenzyme, aspartate transaminase, cholesterol, triglycerides and creatinine levels, as well as the cardiac tissues were examined.

Results

Comparing with the control, DOX considerably (p<0.01) up-regulated TNF-α expression, malondialdehyde, nitric oxide, cardiac enzymes, lipids and creatinine levels, while it significantly (p<0.01) down-regulated Nrf2 and CBR1. Additionally, DOX interfered with antioxidant enzymes' activities (p<0.01). Conversely, protected groups showed a significant (p<0.01) amelioration of DOX-induced cardiotoxic effects.

Conclusion

The current study provides a new understanding of P. maculosa and C. sinensis cardioprotective mechanisms. The extracts' cardioprotective effects may be due to their antioxidant activities, ability to maintain the redox homeostasis through regulation of important antioxidant genes and primary antioxidant enzymes, and capability to recover inflammatory cytokines and lipids levels. Noteworthy, the tested extracts showed no toxic changes on the normal mice.

Functional Validation of Doxorubicin-Induced Cardiotoxicity-Related Genes

Background

Genome-wide association studies and candidate gene association studies have identified more than 180 genetic variants statistically associated with anthracycline-induced cardiotoxicity (AIC). However, the lack of functional validation has hindered the clinical translation of these findings.

Objectives

The aim of this study was to functionally validate all genes associated with AIC using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).

Methods

Through a systemic literature search, 80 genes containing variants significantly associated with AIC were identified. Additionally, 3 more genes with potential roles in AIC (GSTM1, CBR1, and ERBB2) were included. Of these, 38 genes exhibited expression in human fetal heart, adult heart, and hiPSC-CMs. Using clustered regularly interspaced short palindromic repeats/Cas9-based genome editing, each of these 38 genes was systematically knocked out in control hiPSC-CMs, and the resulting doxorubicin-induced cardiotoxicity (DIC) phenotype was assessed using hiPSC-CMs. Subsequently, functional assays were conducted for each gene knockout on the basis of hypothesized mechanistic implications in DIC.

Results

Knockout of 26 genes increased the susceptibility of hiPSC-CMs to DIC. Notable genes included efflux transporters (ABCC10, ABCC2, ABCB4, ABCC5, and ABCC9), well-established DIC-associated genes (CBR1, CBR3, and RAC2), and genome-wide association study-discovered genes (RARG and CELF4). Conversely, knockout of ATP2B1, HNMT, POR, CYBA, WDR4, and COL1A2 had no significant effect on the in vitro DIC phenotype of hiPSC-CMs. Furthermore, knockout of the uptake transporters (SLC28A3, SLC22A17, and SLC28A1) demonstrated a protective effect against DIC.

Conclusions

The present findings establish a comprehensive platform for the functional validation of DIC-associated genes, providing insights for future studies in DIC variant associations and potential mechanistic targets for the development of cardioprotective drugs.

Fabrication and application of glutathione biosensing SPCE strips with gold nanoparticle modification

Glutathione (GSH) is a major antioxidant in organisms. An alteration in GSH concentration has been implicated in a number of pathological conditions. Therefore, GSH sensing has become a critical issue. In this study, a disposable strip used for tyrosinase-modified electrochemical testing was fabricated for the detection of GSH levels in vivo. The system is based on tyrosinase as a biorecognition element and a screen-printed carbon electrode (SPCE) as an amperometric transducer. On the tyrosinase-SPCE strips, the oxidation reaction from catechol to o-quinone was catalyzed by tyrosinase. The tyrosinase-SPCE strips were modified with gold nanoparticles (AuNPs). In the presence of AuNPs of 25 nm diameter, the cathodic peak current of cyclic voltammetry (CV) was significantly enhanced by 5.2 fold. Under optimized conditions (250 μM catechol, 50 mM phosphate buffer, and pH 6.5), the linear response of the tyrosinase-SPCE strips ranged from 31.25 to 500 μM GSH, with a detection limit of approximately 35 μM (S/N > 3). The tyrosinase-SPCE strips have been used to detect real samples of plasma and tissue homogenates in a mouse experiment. The mice were orally administrated with N-acetylcysteine (NAC) 100 mg kg-1 once a day for 7 days; the plasma GSH significantly enhanced 2.8 fold as compared with saline-treated mice (1123 vs. 480 μM μg-1 protein). NAC administration also could alleviate the adverse effect of GSH reduction in the mice treated with doxorubicin.

Azilsartan improves doxorubicin-induced cardiotoxicity via inhibiting oxidative stress, proinflammatory pathway, and apoptosis

Azilsartan, a known angiotensin receptor blocker, has shown potential in reducing 24-hour blood pressure and may have protective effects against cardiac complications. Increased oxidative stress in cardiac tissue is directly related to the cardiac complications of doxorubicin. This study investigated whether azilsartan could mitigate doxorubicin-induced cardiotoxicity. We divided 28 male rats into four groups: the control group receiving a standard diet and water, the vehicle group given DMSO orally for two weeks, doxorubicin group receiving 2.5 mg/kg of doxorubicin three times a week for two weeks, and azilsartan group treated with 5 mg/kg/day of azilsartan orally and doxorubicin. Doxorubicin-induced cardiotoxicity was evidenced by a significant increase in TNF-α, IL-1β, MDA, and caspase-3 levels and significantly decreased TAC and Bcl-2 levels in the cardiac tissues of treated rats compared to the DMSO and control groups. Azilsartan significantly decreased doxorubicin-induced cardiotoxicity, as evidenced by a decline in serum levels of both TNF-α and IL-1β. Additionally, MDA significantly decreased in the cardiac tissue, although TAC was significantly increased when comparing the azilsartan group to the group receiving doxorubicin-only. These results suggest that azilsartan effectively reduced doxorubicin-induced cardiotoxicity, likely by mitigating apoptosis, inflammation, and oxidative stress in cardiac tissues.

Doxorubicin covalently conjugated heparin displays anti-cancer activity as a self-assembled nanoparticle with a low-anticoagulant effect

Heparin is a glycosaminoglycans (GAGs) member and well-known FDA-approved anticoagulant that has been widely used in the clinic for 100 years. It has also been evaluated in various fields for further clinical applications, such as in anti-cancer or anti-inflammatory therapy beyond its anticoagulant effect. Here, we sought to utilize heparin molecules as drug carriers by directly conjugating the anticancer drug doxorubicin to the carboxyl group of unfractionated heparin. Given the molecular action of doxorubicin in intercalating DNA, it is expected to be less effective when structurally combined with other molecules. However, by utilizing doxorubicin molecules to produce reactive oxygen species (ROS), we found that the heparin-doxorubicin conjugates have significant cytotoxic ability to kill CT26 tumor cells with low anticoagulant activity. Several doxorubicin molecules were bound to heparin to provide sufficient cytotoxic capability and self-assembly ability due to their amphiphilic properties. The self-assembled formation of these nanoparticles was demonstrated through DLS, SEM and TEM. The cytotoxic ROS-generating doxorubicin-conjugated heparins could inhibit tumor growth and metastasis in CT26-bearing Balb/c animal models. Our results demonstrate that this cytotoxic doxorubicin-based heparin conjugate can significantly inhibit tumor growth and metastasis, thus showing promise as a potential new anti-cancer therapeutic.

Underlying the Mechanisms of Doxorubicin-Induced Acute Cardiotoxicity: Oxidative Stress and Cell Death

Cancer is a destructive disease that causes high levels of morbidity and mortality. Doxorubicin (DOX) is a highly efficient antineoplastic chemotherapeutic drug, but its use places survivors at risk for cardiotoxicity. Many studies have demonstrated that multiple factors are involved in DOX-induced acute cardiotoxicity. Among them, oxidative stress and cell death predominate. In this review, we provide a comprehensive overview of the mechanisms underlying the source and effect of free radicals and dependent cell death pathways induced by DOX. Hence, we attempt to explain the cellular mechanisms of oxidative stress and cell death that elicit acute cardiotoxicity and provide new insights for researchers to discover potential therapeutic strategies to prevent or reverse doxorubicin-induced cardiotoxicity.

Phosphoinositide 3-Kinase (PI3K) Reactive Oxygen Species (ROS)-Activated Prodrug in Combination with Anthracycline Impairs PI3K Signaling, Increases DNA Damage Response and Reduces Breast Cancer Cell Growth

RIDR-PI-103 is a novel reactive oxygen species (ROS)-induced drug release prodrug with a self-cyclizing moiety linked to a pan-PI3K inhibitor (PI-103). Under high ROS, PI-103 is released in a controlled manner to inhibit PI3K. The efficacy and bioavailability of RIDR-PI-103 in breast cancer remains unexplored. Cell viability of RIDR-PI-103 was assessed on breast cancer cells (MDA-MB-231, MDA-MB-361 and MDA-MB-453), non-tumorigenic MCF10A and fibroblasts. Matrigel colony formation, cell proliferation and migration assays examined the migratory properties of breast cancers upon treatment with RIDR-PI-103 and doxorubicin. Western blots determined the effect of doxorubicin ± RIDR-PI-103 on AKT activation and DNA damage response. Pharmacokinetic (PK) studies using C57BL/6J mice determined systemic exposure (plasma concentrations and overall area under the curve) and T1/2 of RIDR-PI-103. MDA-MB-453, MDA-MB-231 and MDA-MB-361 cells were sensitive to RIDR-PI-103 vs. MCF10A and normal fibroblast. Combination of doxorubicin and RIDR-PI-103 suppressed cancer cell growth and proliferation. Doxorubicin with RIDR-PI-103 inhibited p-AktS473, upregulated p-CHK1/2 and p-P53. PK studies showed that ~200 ng/mL (0.43 µM) RIDR-PI-103 is achievable in mice plasma with an initial dose of 20 mg/kg and a 10 h T1/2. (4) The prodrug RIDR-PI-103 could be a potential therapeutic for treatment of breast cancer patients.

Cinnamaldehyde and Doxorubicin Co-Loaded Graphene Oxide Wrapped Mesoporous Silica Nanoparticles for Enhanced MCF-7 Cell Apoptosis

Background

Combined chemotherapy is often affected by the different physicochemical properties of chemotherapeutic drugs, which should be improved by the reasonable design of co-loaded preparations.

Purpose

A kind of simple but practical graphene oxide (GO) wrapped mesoporous silica nanoparticles (MSN) modified with hyaluronic acid (MSN@GO-HA) were developed for the co-delivery of cinnamaldehyde (CA) and doxorubicin (DOX), in order to enhance their combined treatment on tumor cells and reduce their application defects.

Methods

The MSN_CA@GO_DOX-HA was constructed by MSN_CA (loading CA via physical diffusion) and GO_DOX-HA (modified with HA and loading DOX via π–π stacking) through the electrostatic adsorption, followed by the physicochemical characterization, serum stability and in vitro release study. Cytotoxicity on different cells was detected, followed by the tumor cell uptake tests. The intracellular reactive oxygen species (ROS) changes, mitochondrial functions and activities of caspase-3/-9 in MCF-7 cells were also evaluated, respectively.

Results

The MSN_CA@GO_DOX-HA nanoparticles kept stable in FBS solution and achieved pH-responsive release behavior, which was beneficial to increase the accumulation of CA and DOX in tumor cells to enhance the treatment. MSN_CA@GO_DOX-HA exerted higher cytotoxicity to MCF-7 human breast cancer cells than H9c2 cardiac myocyte cells, which were not only attributed to the active targeting to tumor cells by HA, but also related with the activation of intrinsic apoptotic pathway in MCF-7 cells induced by CA, which was mediated by the specific ROS signal amplification and the interference with mitochondrial function. Moreover, the efficacy of DOX was also enhanced by the above process.

Conclusion

The establishment of the MSN_CA@GO_DOX-HA nanoparticles played a role in promoting strengths and restricting shortcomings of CA and DOX, thereby exerting their function and achieving efficient treatment against cancer.

Effect of Anticancer Quinones on Reactive Oxygen Production by Adult Rat Heart Myocytes

This study investigated the effect of anthracycline antibiotics, mitomycin C, and menadione on oxygen consumption and hydrogen peroxide production by intact, beating, rat heart myocytes. Doxorubicin produced a dose-dependent increase in the rate of cyanide-resistant respiration by beating myocytes. The anthracycline analogs 4-demethoxydaunorubicin, 4′-epidoxorubicin, 4′-deoxydoxorubicin, and menogaril, as well as the anticancer quinones mitomycin C and menadione, also significantly increased oxygen consumption by cardiac myocytes. However, 5-iminodaunorubicin (which has a substituted quinone group) and mitoxantrone (which is not easily reduced by flavin dehydrogenases) had no effect on cardiac respiration. Both catalase (43%) and acetylated cytochrome c (19%) significantly decreased oxygen consumption that had been stimulated by doxorubicin; furthermore, extracellular hydrogen peroxide production was increased from undetectable control levels to 1.30 ± 0.02 nmol/min/10⁷ myocytes (n = 4, P < 0.01) in the presence of 400 μM doxorubicin. These experiments suggest that the anthracycline antibiotics and other anticancer quinones stimulate cardiac oxygen radical production in intact heart myocytes; such a free radical cascade could contribute to the cardiac toxicity of these drugs.