A novel insight into the cardiotoxicity of antineoplastic drug doxorubicin

Protective Effects of Hippophae rhamnoides L. Phenylpropanoids on Doxorubicin-Induced Cardiotoxicity in Zebrafish

Hippophae rhamnoides L. is a deciduous shrub that contains many unique bioactive substances. This sea buckthorn possesses anticancer, antioxidant, anti-inflammatory, and cardiovascular protective properties. Herein, the effects of phenylpropyl compounds extracted from H. rhamnoides L. on doxorubicin (Dox)-induced cardiotoxicity were evaluated in zebrafish. Cardiac injury in zebrafish was induced using 35 μM Dox for 96 h, and 30 μM phenylpropanoid compounds were used as the protective treatment. The cardioprotective effects and mechanisms of the four phenylpropanoids were investigated using microscopy, behavioral analysis, acridine orange staining, western blotting, flow cytometry, and real-time quantitative polymerase chain reaction. The extracted phenylpropanoids could significantly relieve Dox-induced cardiac injury in zebrafish and inhibit cardiomyocyte apoptosis. The mechanisms of action were mainly related to the stability of mitochondrial biogenesis and function maintained by phenylpropanoids in zebrafish. To our knowledge, this is the first report on the protective effect of sea buckthorn against myocardial injury in zebrafish. Our findings provide support for the further research and development of sea buckthorn and its components.

Platinum-based drug-induced depletion of amino acids in the kidneys and liver

Cisplatin (cis-diamminedichloroplatinum II; CDDP) is a widely used cytostatic agent; however, it tends to promote kidney and liver disease, which are a major signs of drug-induced toxicity. Platinum compounds are often presented as alternative therapeutics and subsequently easily dispersed in the environment as contaminants. Due to the major roles of the liver and kidneys in removing toxic materials from the human body, we performed a comparative study of the amino acid profiles in chicken liver and kidneys before and after the application of CDDP and platinum nanoparticles (PtNPs-10 and PtNPs-40). The treatment of the liver with the selected drugs affected different amino acids; however, Leu and Arg were decreased after all treatments. The treatment of the kidneys with CDDP mostly affected Val; PtNPs-10 decreased Val, Ile and Thr; and PtNPs-40 affected only Pro. In addition, we tested the same drugs on two healthy cell lines, HaCaT and HEK-293, and ultimately explored the amino acid profiles in relation to the tricarboxylic acid cycle (TCA) and methionine cycle, which revealed that in both cell lines, there was a general increase in amino acid concentrations associated with changes in the concentrations of the metabolites of these cycles.

Physiological Roles of Carnosine in Myocardial Function and Health

Carnosine is a pleiotropic histidine-containing dipeptide synthesized from β-alanine and l-histidine, with the intact dipeptide and constituent amino acids being available from the diet. The therapeutic application of carnosine in myocardial tissue is promising, with carnosine playing a potentially beneficial role in both healthy and diseased myocardial models. This narrative review discusses the role of carnosine in myocardial function and health, including an overview of the metabolic pathway of carnosine in the myocardial tissue, the roles carnosine may play in the myocardium, and a critical analysis of the literature, focusing on the effect of exogenous carnosine and its precursors on myocardial function. By so doing, we aim to identify current gaps in the literature, thereby identifying considerations for future research.

Protective effect of valsartan against doxorubicin-induced cardiotoxicity: Histopathology and metabolomics in vivo study

Doxorubicin (DOX) treatment has been associated with cardiotoxicity. Therefore, it is crucial to search for a therapeutic that can effectively mitigate DOX-induced cardiotoxicity. This study was conducted to investigate the protective effects of valsartan (VAL) against DOX-induced cardiotoxicity. Sprague-Dawley rats were divided into four treatment groups: Group I: Control, Group II: VAL (30 mg/kg, ip), Group III: DOX (15 mg/kg, ip), and Group IV: VAL + DOX (30 + 15 mg/kg, ip). All groups were treated every other day for 14 days. Blood was isolated for biochemical and metabolomics studies, and sections of the heart were also analyzed for histopathological and immunohistochemical alterations to detect changes in P53, BAX, BCL-2, and P62 expression. The combination of VAL + DOX resulted in a marked decrease in cardiac biomarker enzymes (aminotransferase and creatine phosphokinase) compared to DOX monotherapy. In addition, the histopathological examination of the VAL + DOX combination revealed a low percentage of fibrosis and inflammation. Immunohistochemical expression of p53 and BAX was significantly reduced, whereas BCL-2 expression was significantly increased in the VAL + DOX treatment group compared to DOX monotherapy. Also, the combination of VAL + DOX reverses the negative effect of DOX on nuclear p62 expression. Analysis of serum metabolites showed that DOX monotherapy reduced the number of several amino acids, whereas the combination of VAL + DOX restored these metabolic pathways. This study revealed the potential cardioprotective effect of VAL, which may provide novel and promising approaches for managing cardiotoxicity induced by DOX.

A multiplexed in vitro assay system for evaluating human skeletal muscle functionality in response to drug treatment

In vitro systems that mimic organ functionality have become increasingly important tools in drug development studies. Systems that measure the functional properties of skeletal muscle are beneficial to compound screening studies and also for integration into multiorgan devices. To date, no studies have investigated human skeletal muscle responses to drug treatments at the single myotube level in vitro. This report details a microscale cantilever chip-based assay system for culturing individual human myotubes. The cantilevers, along with a laser and photo-detector system, enable measurement of myotube contractions in response to broad-field electrical stimulation. This system was used to obtain baseline functional parameters for untreated human myotubes, including peak contractile force and time-to-fatigue data. The cultured myotubes were then treated with known myotoxic compounds and the resulting functional changes were compared to baseline measurements as well as known physiological responses in vivo. The collected data demonstrate the system's capacity for screening direct effects of compound action on individual human skeletal myotubes in a reliable, reproducible, and noninvasive manner. Furthermore, it has the potential to be utilized for high-content screening, disease modeling, and exercise studies of human skeletal muscle performance utilizing iPSCs derived from specific patient populations such as the muscular dystrophies.

Identification of Human Enzymes Oxidizing the Anti-Thyroid-Cancer Drug Vandetanib and Explanation of the High Efficiency of Cytochrome P450 3A4 in its Oxidation

The metabolism of vandetanib, a tyrosine kinase inhibitor used for treatment of symptomatic/progressive medullary thyroid cancer, was studied using human hepatic microsomes, recombinant cytochromes P450 (CYPs) and flavin-containing monooxygenases (FMOs). The role of CYPs and FMOs in the microsomal metabolism of vandetanib to N-desmethylvandetanib and vandetanib-N-oxide was investigated by examining the effects of CYP/FMO inhibitors and by correlating CYP-/FMO-catalytic activities in each microsomal sample with the amounts of N-desmethylvandetanib/vandetanib-N-oxide formed by these samples. CYP3A4/FMO-activities significantly correlated with the formation of N-desmethylvandetanib/ vandetanib-N-oxide. Based on these studies, most of the vandetanib metabolism was attributed to N-desmethylvandetanib/vandetanib-N-oxide to CYP3A4/FMO3. Recombinant CYP3A4 was most efficient to form N-desmethylvandetanib, while FMO1/FMO3 generated N-oxide. Cytochrome b₅ stimulated the CYP3A4-catalyzed formation of N-desmethylvandetanib, which is of great importance because CYP3A4 is not only most efficient in generating N-desmethylvandetanib, but also most significant due to its high expression in human liver. Molecular modeling indicated that binding of more than one molecule of vandetanib into the CYP3A4-active center can be responsible for the high efficiency of CYP3A4 N-demethylating vandetanib. Indeed, the CYP3A4-mediated reaction exhibits kinetics of positive cooperativity and this corresponded to the in silico model, where two vandetanib molecules were found in CYP3A4-active center.

Ex Vivo Cardiotoxicity of Antineoplastic Casiopeinas Is Mediated through Energetic Dysfunction and Triggered Mitochondrial-Dependent Apoptosis

Casiopeinas are a group of copper-based antineoplastic molecules designed as a less toxic and more therapeutic alternative to cisplatin or Doxorubicin; however, there is scarce evidence about their toxic effects on the whole heart and cardiomyocytes. Given this, rat hearts were perfused with Casiopeinas or Doxorubicin and the effects on mechanical performance, energetics, and mitochondrial function were measured. As well, the effects of Casiopeinas-triggered cell death were explored in isolated cardiomyocytes. Casiopeinas III-Ea, II-gly, and III-ia induced a progressive and sustained inhibition of heart contractile function that was dose- and time-dependent with an IC₅₀ of 1.3 ± 0.2, 5.5 ± 0.5, and 10 ± 0.7 μM, correspondingly. Myocardial oxygen consumption was not modified at their respective IC₅₀, although ATP levels were significantly reduced, indicating energy impairment. Isolated mitochondria from Casiopeinas-treated hearts showed a significant loss of membrane potential and reduction of mitochondrial Ca²⁺ retention capacity. Interestingly, Cyclosporine A inhibited Casiopeinas-induced mitochondrial Ca²⁺ release, which suggests the involvement of the mitochondrial permeability transition pore opening. In addition, Casiopeinas reduced the viability of cardiomyocytes and stimulated the activation of caspases 3, 7, and 9, demonstrating a cell death mitochondrial-dependent mechanism. Finally, the early perfusion of Cyclosporine A in isolated hearts decreased Casiopeinas-induced dysfunction with reduction of their toxic effect. Our results suggest that heart cardiotoxicity of Casiopeinas is similar to that of Doxorubicin, involving heart mitochondrial dysfunction, loss of membrane potential, changes in energetic metabolites, and apoptosis triggered by mitochondrial permeability.

Protective Effects of Dexrazoxane against Doxorubicin-Induced Cardiotoxicity: A Metabolomic Study

Cardioprotection of dexrazoxane (DZR) against doxorubicin (DOX)-induced cardiotoxicity is contentious and the indicator is controversial. A pairwise comparative metabolomics approach was used to delineate the potential metabolic processes in the present study. Ninety-six BALB/c mice were randomly divided into two supergroups: tumor and control groups. Each supergroup was divided into control, DOX, DZR, and DOX plus DZR treatment groups. DOX treatment resulted in a steady increase in 5-hydroxylysine, 2-hydroxybutyrate, 2-oxoglutarate, 3-hydroxybutyrate, and decrease in glucose, glutamate, cysteine, acetone, methionine, asparate, isoleucine, and glycylproline.DZR treatment led to increase in lactate, 3-hydroxybutyrate, glutamate, alanine, and decrease in glucose, trimethylamine N-oxide and carnosine levels. These metabolites represent potential biomarkers for early prediction of cardiotoxicity of DOX and the cardioprotective evaluation of DZR.

Sarcosine Up-Regulates Expression of Genes Involved in Cell Cycle Progression of Metastatic Models of Prostate Cancer

The effects of sarcosine on the processes driving prostate cancer (PCa) development remain still unclear. Herein, we show that a supplementation of metastatic PCa cells (androgen independent PC-3 and androgen dependent LNCaP) with sarcosine stimulates cells proliferation in vitro. Similar stimulatory effects were observed also in PCa murine xenografts, in which sarcosine treatment induced a tumor growth and significantly reduced weight of treated mice (p < 0.05). Determination of sarcosine metabolism-related amino acids and enzymes within tumor mass revealed significantly increased glycine, serine and sarcosine concentrations after treatment accompanied with the increased amount of sarcosine dehydrogenase. In both tumor types, dimethylglycine and glycine-N-methyltransferase were affected slightly, only. To identify the effects of sarcosine treatment on the expression of genes involved in any aspect of cancer development, we further investigated expression profiles of excised tumors using cDNA electrochemical microarray followed by validation using the semi-quantitative PCR. We found 25 differentially expressed genes in PC-3, 32 in LNCaP tumors and 18 overlapping genes. Bioinformatical processing revealed strong sarcosine-related induction of genes involved particularly in a cell cycle progression. Our exploratory study demonstrates that sarcosine stimulates PCa metastatic cells irrespectively of androgen dependence. Overall, the obtained data provides valuable information towards understanding the role of sarcosine in PCa progression and adds another piece of puzzle into a picture of sarcosine oncometabolic potential.

Relation of exposure to amino acids involved in sarcosine metabolic pathway on behavior of non-tumor and malignant prostatic cell lines

BACKGROUND

Sarcosine (N-methylglycine) was previously delineated as a substantial oncometabolite of prostate cancer (PCa) and its metabolism seems to be significantly involved in PCa development and behavior.

METHODS

We focused on investigation whether the exposure of prostate cells (PNT1A, 22Rv1, and PC-3) to sarcosine-related amino acids (glycine, dimethylglycine, and sarcosine) affects their aggressiveness (cell mobility and division rates, using real-time cell based assay). The effect of supplementation on expression of glycine-N-methyltransferase (GNMT) mRNA was examined using qRT-PCR. Finally, post-treatment amino acids patterns were determined with consequent statistical processing using the Ward's method, factorial ANOVA and principal component analysis (P < 0.05).

RESULTS

The highest migration induced sarcosine and glycine in metastatic PC-3 cells (a decrease in relative free area about 53% and 73%). The highest cell division was achieved after treatment of 22Rv1 and PC-3 cells with sarcosine (time required for division decreased by 65% or 45%, when compared to untreated cells). qRT-PCR revealed also significant effects on expression of GNMT. Finally, amino acid profiling shown specific amino acid patterns for each cell line. In both, treated and untreated PC-3 cells significantly higher levels of serine, glutamic acid, and aspartate, linked with prostate cancer progression were found.

CONCLUSIONS

Sarcosine-related amino acids can exceptionally affect the behavior of benign and malignant prostate cells.

Improved antitumor activity and reduced myocardial toxicity of doxorubicin encapsulated in MPEG-PCL nanoparticles

Doxorubicin (Dox) is a broad-spectrum antitumor drug used for the treatment of many types of malignant tumors. Although it possesses powerful antitumor activity, its clinical application is seriously encumbered by its unselective distribution and systemic toxicities, particularly myocardial toxicity. Thus, it is imperative to modify Dox to decrease its systemic toxicities and improve its therapeutic index. In the present study, we adopted a novel type of monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL) micelles to encapsulate Dox to prepare Dox-loaded MPEG-PCL (Dox/MPEG-PCL) nanoparticles by a controllable self-assembly process. The cellular uptake efficiency and cell proliferation inhibition of the Dox/MPEG-PCL nanoparticles were examined. The antitumor activity of the Dox/MPEG-PCL nanoparticles was tested on a multiple pulmonary metastasis model of melanoma on C57BL/6 mice. Systemic toxicities and survival time were compared between the mice treated with the Dox/MPEG-PCL nanoparticles and free Dox. The potential myocardial toxicity of the Dox/MPEG-PCL nanoparticles was investigated using a prolonged observation period. Encapsulation of Dox in MPEG-PCL nanoparticles significantly improved the cellular uptake and cell proliferation inhibition of Dox in vivo. Intravenous injection of Dox/MPEG-PCL nanoparticles obtained significant inhibition of the growth and metastasis of melanoma in the lung and prolonged survival time compared with free Dox (P<0.05). The Dox/MPEG-PCL nanoparticles did not show obvious additional systemic toxicities compared with free Dox during the treatment time. During the prolonged observation period, obvious decreased cardiac toxicity was observed in the Dox/MPEG-PCL nanoparticle-treated mice compared with that observed in the free Dox-treated mice. These results indicated that encapsulating Dox with MPEG-PCL micelles could significantly promote its antitumor activity and reduce its toxicity to the myocardium.

Early metabolomics changes in heart and plasma during chronic doxorubicin treatment in B6C3F1 mice

The present study aimed to identify molecular markers of early stages of cardiotoxicity induced by a potent chemotherapeutic agent, doxorubicin (DOX). Male B6C3F1 mice were dosed with 3 mg kg(-1) DOX or saline via tail vein weekly for 2, 3, 4, 6 or 8 weeks (cumulative DOX doses of 6, 9, 12, 18 or 24 mg kg(-1) , respectively) and euthanized a week after the last dose. Mass spectrometry-based and nuclear magnetic resonance spectrometry-based metabolic profiling were employed to identify initial biomarkers of cardiotoxicity before myocardial injury and cardiac pathology, which were not noted until after the 18 and 24 mg kg(-1) cumulative doses, respectively. After a cumulative dose of 6 mg kg(-1) , 18 amino acids and four biogenic amines (acetylornithine, kynurenine, putrescine and serotonin) were significantly increased in cardiac tissue; 16 amino acids and two biogenic amines (acetylornithine and hydroxyproline) were significantly altered in plasma. In addition, 16 acylcarnitines were significantly increased in plasma and five were significantly decreased in cardiac tissue compared to saline-treated controls. Plasma lactate and succinate, involved in the Krebs cycle, were significantly altered after a cumulative dose of 6 mg kg(-1) . A few metabolites remained altered at higher cumulative DOX doses, which could partly indicate a transition from injury processes at 2 weeks to repair processes with additional injury happening concurrently before myocardial injury at 8 weeks. These altered metabolic profiles in mouse heart and plasma during the initial stages of injury progression due to DOX treatment may suggest these metabolites as candidate early biomarkers of cardiotoxicity. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Antineoplastic copper coordinated complexes (Casiopeinas) uncouple oxidative phosphorylation and induce mitochondrial permeability transition in cardiac mitochondria and cardiomyocytes

Copper-based drugs, Casiopeinas (Cas), exhibit antiproliferative and antineoplastic activities in vitro and in vivo, respectively. Unfortunately, the clinical use of these novel chemotherapeutics could be limited by the development of dose-dependent cardiotoxicity. In addition, the molecular mechanisms underlying Cas cardiotoxicity and anticancer activity are not completely understood. Here, we explore the potential impact of Cas on the cardiac mitochondria energetics as the molecular mechanisms underlying Cas-induced cardiotoxicity. To explore the properties on mitochondrial metabolism, we determined Cas effects on respiration, membrane potential, membrane permeability, and redox state in isolated cardiac mitochondria. The effect of Cas on the mitochondrial membrane potential (Δψm) was also evaluated in isolated cardiomyocytes by confocal microscopy and flow cytometry. Cas IIIEa, IIgly, and IIIia predominately inhibited maximal NADH- and succinate-linked mitochondrial respiration, increased the state-4 respiration rate and reduced membrane potential, suggesting that Cas also act as mitochondrial uncouplers. Interestingly, cyclosporine A inhibited Cas-induced mitochondrial depolarization, suggesting the involvement of mitochondrial permeability transition pore (mPTP). Similarly to isolated mitochondria, in isolated cardiomyocytes, Cas treatment decreased the Δψm and cyclosporine A treatment prevented mitochondrial depolarization. The production of H2O2 increased in Cas-treated mitochondria, which might also increase the oxidation of mitochondrial proteins such as adenine nucleotide translocase. In accordance, an antioxidant scavenger (Tiron) significantly diminished Cas IIIia mitochondrial depolarization. Cas induces a prominent loss of membrane potential, associated with alterations in redox state, which increases mPTP opening, potentially due to thiol-dependent modifications of the pore, suggesting that direct or indirect inhibition of mPTP opening might reduce Cas-induced cardiotoxicity.

Doxorubicin resistance in breast cancer is driven by light at night-induced disruption of the circadian melatonin signal

Chemotherapeutic resistance, particularly to doxorubicin (Dox), represents a major impediment to successfully treating breast cancer and is linked to elevated tumor metabolism and tumor over-expression and/or activation of various families of receptor- and non-receptor-associated tyrosine kinases. Disruption of circadian time structure and suppression of nocturnal melatonin production by dim light exposure at night (dLEN), as occurs with shift work, and/or disturbed sleep-wake cycles, is associated with a significantly increased risk of an array of diseases, including breast cancer. Melatonin inhibits human breast cancer growth via mechanisms that include the suppression of tumor metabolism and inhibition of expression or phospho-activation of the receptor kinases AKT and ERK1/2 and various other kinases and transcription factors. We demonstrate in tissue-isolated estrogen receptor alpha-positive (ERα+) MCF-7 human breast cancer xenografts, grown in nude rats maintained on a light/dark cycle of LD 12:12 in which dLEN is present during the dark phase (suppressed endogenous nocturnal melatonin), a significant shortening of tumor latency-to-onset, increased tumor metabolism and growth, and complete intrinsic resistance to Dox therapy. Conversely, a LD 12:12 dLEN environment incorporating nocturnal melatonin replacement resulted in significantly lengthened tumor latency-to-onset, tumor regression, suppression of nighttime tumor metabolism, and kinase and transcription factor phosphorylation, while Dox sensitivity was completely restored. Melatonin acts as both a tumor metabolic inhibitor and circadian-regulated kinase inhibitor to reestablish the sensitivity of breast tumors to Dox and drive tumor regression, indicating that dLEN-induced circadian disruption of nocturnal melatonin production contributes to a complete loss of tumor sensitivity to Dox chemotherapy.

Beneficial effects of carnosine and carnosine plus vitamin E treatments on doxorubicin-induced oxidative stress and cardiac, hepatic, and renal toxicity in rats

OBJECTIVE

Oxidative stress plays an important role in doxorubicin (DOX)-induced toxicity. Carnosine (CAR) is a dipeptide with antioxidant properties. The aim of this study was to evaluate the decreasing or preventive effect of CAR alone or combination with vitamin E (CAR + Vit E) on DOX-induced toxicity in heart, liver, and brain of rats.

METHODS

Rats were treated with CAR (250 mg kg(-1) day(-1); intraperitoneally (i.p.)) or CAR + Vit E (equals 200 mg kg(-1) α-tocopherol; once every 3 days; intramuscularly) for 12 consecutive days. On the 8th day of treatment, rats were injected with a single dose of DOX (30 mg kg(-1), i.p.). Serum cardiac troponin I (cTnI), urea, and creatinine levels; alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities; and oxidative stress parameters in tissues were measured. We also determined thiobarbituric acid reactive substances, diene conjugate, protein carbonyl (PC), and glutathione levels and antioxidant enzyme activities.

RESULTS

DOX resulted in increased serum cTnI, ALT, AST, urea, and creatinine levels and increased lipid peroxide and PC levels in tissues. CAR or CAR + Vit E treatments led to decreases in serum cTnI levels and ALT and AST activities. These treatments reduced prooxidant status and ameloriated histopathologic findings in the examined tissues.

CONCLUSION

Our results may indicate that CAR alone, especially in combination with Vit E, protect against DOX-induced toxicity in heart, liver, and kidney tissues of rats. This was evidenced by improved cardiac, hepatic, and renal markers and restoration of the prooxidant state and amelioration of histopathologic changes.

Co-delivery of doxorubicin and SATB1 shRNA by thermosensitive magnetic cationic liposomes for gastric cancer therapy

In previous a study, we had developed a novel thermosensitive magnetic delivery system based on liposomes. This study aimed to evaluate the efficiency of this system for the co-delivery of both drugs and genes to the same cell and its anti-tumor effects on gastric cancer. Doxorubicin (DOX) and SATB1 shRNA vector were loaded into the co-delivery system, and in vitro DOX thermosensitive release activity, targeted gene silencing efficiency, targeted cellular uptake, in vitro cytotoxicity, as well as in vivo anti-tumor activity were determined. The results showed that this co-delivery system had desirable targeted delivery efficacy, DOX thermosensitive release and SATB1 gene silencing. Moreover, the co-delivery of DOX and SATB1 shRNA exhibited enhanced activity to inhibit gastric cancer cell growth in vitro and in vivo, compared to single delivery. In conclusion, the novel thermosensitive magnetic drug and gene co-delivery system has promising application in combined chemotherapy and gene therapy for gastric cancer.