The beneficial effect of n-3 polyunsaturated fatty acids on doxorubicin-induced chronic heart failure in rats

Cardiovascular Diseases and Marine Oils: A Focus on Omega-3 Polyunsaturated Fatty Acids and Polar Lipids

Cardiovascular diseases (CVD) remain the leading cause of death across the globe, hence, establishing strategies to counteract CVD are imperative to reduce mortality and the burden on health systems. Dietary modification is an effective primary prevention strategy against CVD. Research regarding dietary supplementation has become increasingly popular. This review focuses on the current in vivo, in vitro, and epidemiological studies associated with that of omega-3 polyunsaturated fatty acids (n-3 PUFAs) and polar lipids (PLs) and how they play a role against CVD. Furthermore, this review focuses on the results of several major clinical trials examining n-3 PUFAs regarding both primary and secondary prevention of CVD. Notably, we place a lens on the REDUCE-IT and STRENGTH trials. Finally, supplementation of PLs has recently been suggested as a potential alternative avenue for the reduction of CVD incidence versus neutral forms of n-3 PUFAs. However, the clinical evidence for this argument is currently rather limited. Therefore, we draw on the current literature to suggest future clinical trials for PL supplementation. We conclude that despite conflicting evidence, future human trials must be completed to confirm whether PL supplementation may be more effective than n-3 PUFA supplementation to reduce cardiovascular risk.

The Protective Effect of Citronellol against Doxorubicin-Induced Cardiotoxicity in Rats

Citronellol has been reported to have anti-inflammatory, anti-cancer, and antihypertensive activities, but its effect on myocardial ischemia is still unclear. The aim of this study was to investigate the therapeutic effects and pharmacological mechanisms of citronellol on ischemia. Therefore, a rat model of myocardial ischemia was established using the doxorubicin (DOX) model. To induce cardiotoxicity, the rats were given DOX (2.5 mg/kg) intraperitoneally over a 14-day period. Group I served as the control and received tween 80 (0.2%), group II received the vehicle and DOX, group III received the standard drug dexrazoxane and DOX, whereas groups IV, V, and VI were treated orally with citronellol (25, 50, and 100 mg/kg) and DOX, respectively. After treatment, the rats were euthanized, and blood samples were collected to assess the levels of serum cardiac markers, lipid profiles, and tissue antioxidant enzymes. The gene expressions of eNOS, PPAR-g, IL-10, VEGF, and NFkB-1 were also determined using real-time polymerase chain reactions. Simultaneous treatment with DOX and citronellol reduced cardiac antioxidant enzymes and lipid biomarkers in a dose-dependent manner. Citronellol also increased the expression of anti-inflammatory cytokines while reducing the expression of pro-inflammatory cytokines. Therefore, it can be concluded that citronellol may have potential cardioprotective effects in preventing DOX-induced cardiotoxicity.

Potential of natural products in combination with arsenic trioxide: Investigating cardioprotective effects and mechanisms

Over the past few decades, clinical trials conducted worldwide have demonstrated the efficacy of arsenic trioxide (ATO) in the treatment of relapsed acute promyelocytic leukemia (APL). Currently, ATO has become the frontline treatments for patients with APL. However, its therapeutic applicability is severely constrained by ATO-induced cardiac side effects. Any cardioprotective agents that can ameliorate the cardiac side effects and allow exploiting the full therapeutic potential of ATO, undoubtedly gain significant attention. The knowledge and use of natural products for evidence-based therapy have grown rapidly in recent years. Here we discussed the potential mechanism of ATO-induced cardiac side effects and reviewed the studies on cardiac side effects as well as the research history of ATO in the treatment of APL. Then, We summarized the protective effects and underlying mechanisms of natural products in the treatment of ATO-induced cardiac side effects. Based on the efficacy and safety of the natural product, it has a promising future in the development of cardioprotective agents against ATO-induced cardiac side effects.

Protective Effects of Omega-3 Supplementation against Doxorubicin-Induced Deleterious Effects on the Liver and Kidneys of Rats

Anthracycline doxorubicin (DOX) is still widely used as a chemotherapeutic drug for some solid tumors. Although DOX is highly effective, its side effects are limiting factors, such as cardio, nephro and hepatotoxicity. As such, approaches used to mitigate these adverse effects are highly encouraged. Omega 3 (ω-3), which is a class of long-chain polyunsaturated fatty acids, has been shown to have anti-inflammatory and antioxidant effects in preclinical bioassays. Thus, we evaluated the protective effects of ω-3 supplementation on hepatotoxicity and nephrotoxicity induced by multiple DOX administrations in rodents. Male Wistar rats (10 rats/group) were treated daily with ω-3 (400 mg/kg/day) by gavage for six weeks. Two weeks after the first ω-3 administration, the rats received DOX (3.5 mg/kg, intraperitoneal, 1×/week) for four weeks. DOX treatment reduced body weight gain increased systemic genotoxicity and caused liver-related (increase in serum ALT levels, thickness of the Glisson’s capsule, compensatory proliferation and p65 levels) and kidney-related (increase in serum urea and creatinine levels, and incidence of tubular dilatation) deleterious outcomes. In contrast, ω-3 supplementation was safe and abrogated the DOX-related enhancement of systemic genotoxicity, serum urea and creatinine levels. Furthermore, ω-3 intervention reduced by 50% the incidence of kidney histological lesions while reducing by 40–50% the p65 protein level, and the proliferative response in the liver induced by DOX. Our findings indicate that ω-3 intervention attenuated the DOX-induced deleterious effects in the liver and kidney. Therefore, our findings may inspire future mechanistical investigations and clinical interventions with ω-3 on the reported outcomes.

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/.

Omega 3 fatty acids can reduce early doxorubicin-induced cardiotoxicity in children with acute lymphoblastic leukemia

OBJECTIVES

Omega 3 polyunsaturated fatty acids are dietary factors with several beneficial cardiovascular effects. This study aimed to assess the possible protective effect of omega 3 fatty acids on early doxorubicin-induced cardiac toxicity in children with acute lymphoblastic leukemia (ALL).

PATIENTS AND METHODS

Sixty children of newly diagnosed ALL were randomized into two groups: group I (n = 30) who received omega 3 fatty acids 1000 mg/day for 6 months in addition to their usual protocol of chemotherapy including doxorubicin; and group II (n = 30) who received their usual doxorubicin protocol during the period from February 2020 till August 2021. Echocardiographic examinations were performed before and after the treatment. Glutathione, malondialdehyde (MDA), superoxide dismutase (SOD), troponin I, creatine kinase MB (CK-MB), and N-terminal pro-brain natriuretic peptide (NT-proBNP) were measured also before and after omega 3 treatment.

RESULTS

After 6 months of omega 3 administration, group I had a significantly lower MDA level and a significantly higher glutathione and SOD levels than group II. Similarly, the levels of troponin I, CK-MB, and NT-proBNP were significantly high in group II, whereas they were unchanged in group I after treatment. Similarly, systolic function (presented with peak mitral annular systolic velocity and two-dimensional global longitudinal strain) of the heart was preserved in omega 3-treated patients, unlike the control group that showed significant impairment of left ventricular function after 6 months.

CONCLUSION

Omega 3 fatty acids may decrease early cardiac injury and doxorubicin-induced cardiotoxicity in children with ALL.

Diet impacts triple-negative breast cancer growth, metastatic potential, chemotherapy responsiveness, and doxorubicin-mediated cardiac dysfunction

Anthracyclines are standard-of-care chemotherapy for the treatment of triple-negative breast cancer (TNBC). However, high anthracyclines cumulative doses increase heart failure risk. Designing therapeutic strategies that ameliorate cardiac toxicities without compromising oncologic efficacy are important to improve TNBC outcomes and survivorship. The purpose of this study was to determine the impact of diet on TNBC chemotherapeutic responsiveness and development of chemotherapy-induced cardiac damage. Female BALB/c mice fed a control, Western, Mediterranean, or Western + fish oil diet were injected with 1 × 106 4T1-luciferase TNBC into the mammary fat pad. Tumors grew for 21 days before surgical tumor resection, then mice were treated with 3.3 mg/kg i.v. doxorubicin for 3 weeks. Vevo (R) cardiac ultrasound was performed. Female nu/nu mice were placed on diets before 1 × 105  MDA-MB-231-luciferase TNBC were injected via the tail vein to induce the development of lung metastases. Mice were treated with saline or 3.3 mg/kg i.v. doxorubicin for 3 weeks, and the development of metastases visualized by IVIS (R). Consumption of a high-fat diet increased TNBC growth regardless of dietary pattern. Western diet-fed mice developed lung metastases sooner and displayed increased lung metastatic lesion formation, which was not observed in Mediterranean diet-fed mice. Western diet-fed animals displayed worse cardiac function when compared with Mediterranean diet-fed animals. Hearts from Western diet-fed animals displayed increased fibrosis. Diet represents a modifiable component directly impacting tumor growth, antitumor chemotherapy efficacy, and cardiac toxicities. Our data suggest that the Mediterranean diet may reduce lung metastatic lesions formation and prevent the development of cardiac toxicities.

Effects of Guanxinshutong Capsules as Complementary Treatment in Patients With Chronic Heart Failure: Study Protocol for a Randomized Controlled Trial

Chronic heart failure (CHF) is a common cardiovascular disease with high mortality and a poor prognosis, which places heavy burdens upon society and families. Traditional Chinese medicine (TCM) has been used extensively as complementary treatment for CHF. Guanxinshutong (GXST) capsules are used commonly for the treatment of coronary heart disease (CHD). Experimental research and small-sample clinical trials have shown that GXST can attenuate CHF. However, the effects of GXST as complementary medicine in CHF treatment lack high-quality clinical evidence. We have designed a multicenter, randomized, double-blind, placebo-controlled clinical trial that explores the efficacy and safety of using GXST compared with placebo for patients with CHF with reduced left ventricular ejection fraction (LVEF). A total of 480 participants will be assigned randomly to the GXST group or placebo group at a 2:1 ratio. GXST and placebo will be added to standard treatment for 12 weeks, and then followed up for another 40 weeks. The primary outcome is the improvement value of 6-min walk distance, and the secondary outcomes include plasma levels of N-terminal pro-B-type natriuretic peptide, New York Heart Association classification, Minnesota Living with Heart Failure Questionnaire scores, echocardiographic parameters, and clinical endpoint events. Adverse events will be monitored throughout the trial. Data will be analyzed following a predefined statistical analysis plan. This study will show the effects of the specific use of GXST in CHF patients with reduced LVEF. The Research Ethics Committee of the Second Affiliated Hospital of Zhejiang Chinese Medical University has approved this study (2019-Y-003-02). Written informed consent of patients will be required. This trial is registered in the Chinese Clinical Trial Registry (ChiCTR1900023877). Our results will be disseminated to the public through peer-reviewed journals, academic conferences, and the Internet.

What is considered cardiotoxicity of anthracyclines in animal studies

Anthracyclines are commonly used anticancer drugs with well-known and extensively studied cardiotoxic effects in humans. In the clinical setting guidelines for assessing cardiotoxicity are well-established with important therapeutic implications. Cardiotoxicity in terms of impairment of cardiac function is largely diagnosed by echocardiography and based on objective metrics of cardiac function. Until this day, cardiotoxicity is not an endpoint in the current general toxicology and safety pharmacology preclinical studies, although other classes of drugs apart from anthracyclines, along with everyday chemicals have been shown to manifest cardiotoxic properties. Also, in the relevant literature there are not well-established objective criteria or reference values in order to uniformly characterize cardiotoxic adverse effects in animal models. This in depth review focuses on the evaluation of two important echocardiographic indices, namely ejection fraction and fractional shortening, in the literature concerning anthracycline administration to rats as the reference laboratory animal model. The analysis of the gathered data gives promising results and solid prospects for both, defining anthracycline cardiotoxicity objective values and delineating the guidelines for assessing cardiotoxicity as a separate hazard class in animal preclinical studies for regulatory purposes.

An update on the mechanisms related to cell death and toxicity of doxorubicin and the protective role of nutrients

Doxorubicin (DOX), is a very effective chemotherapeutic agent against cancer whose clinical use is limited by toxicity. Different strategies have been proposed to attenuate toxicity, including combined therapy with bioactive compounds. This review update mechanisms of action and toxicity of doxorubicin and the role of nutrients like vitamins (A, C, E), minerals (selenium) and n-3 polyunsaturated fatty acids. Protective activities against DOX toxicity in liver, kidney, skin, bone marrow, testicles or brain have been reported, but these have not been evaluated for all of the reviewed nutrients. In most cases oxidation-related effects were present either, by reducing ROS levels and/or increasing antioxidant defenses. Antiapoptotic and anti-inflammatory mechanisms are also commonly reported. In some cases, interferences with autophagy and calcium homeostasis also have shown to be affected. Notwithstanding, there is a wide variety in duration and doses of treatment tested for both, compounds and DOX, which make difficult to compare the results of the studies. In spite of the reduction of DOX cardiotoxicity in health models, DOX anti-cancer activity in cancer cell lines or xenograft models usually did not result compromised when this has been evaluated. Importantly, clinical studies are needed to confirm all the observed effects.

Dietary Supplementation with Anti-Inflammatory Omega-3 Fatty Acids for Cardiovascular Protection: Help or Hoax?

Dietary supplementation with omega-3 fatty acids, also known as n-3 fatty acids, has been widely considered cardiovascular protective in the general human population. This widely acclaimed status of omega-3 fatty acids as cardiovascular protective molecules has, however, been questioned by findings from multiple rigorously designed randomized controlled trials, recently reported in the New England Journal of Medicine. Although the anti-inflammatory and other beneficial effects of omega-3 fatty acids are substantiated by research in experimental models as well as findings from observational epidemiological studies, dietary supplementation with omega-3 fatty acids at the typical dosage of 1 g daily does not appear to be an effective strategy for either primary or secondary prevention of cardiovascular disease in humans.

Protective Effects of ω-3 PUFA in Anthracycline-Induced Cardiotoxicity: A Critical Review

It has been demonstrated that ω-3 polyunsaturated fatty acids (ω-3 PUFA) may exert a beneficial role as adjuvants in the prevention and treatment of many disorders, including cardiovascular diseases and cancer. Particularly, several in vitro and in vivo preclinical studies have shown the antitumor activity of ω-3 PUFA in different kinds of cancers, and several human studies have shown that ω-3 PUFA are able to decrease the risk of a series of cardiovascular diseases. Several mechanisms have been proposed to explain their pleiotropic beneficial effects. ω-3 PUFA have also been shown to prevent harmful side-effects (including cardiotoxicity and heart failure) induced by conventional and innovative anti-cancer drugs in both animals and patients. The available literature regarding the possible protective effects of ω-3 PUFA against anthracycline-induced cardiotoxicity, as well as the mechanisms involved, will be critically discussed herein. The study will analyze the critical role of different levels of ω-3 PUFA intake in determining the results of the combinatory studies with anthracyclines. Suggestions for future research will also be considered.

Oxidative Stress and Cellular Response to Doxorubicin: A Common Factor in the Complex Milieu of Anthracycline Cardiotoxicity

The production of reactive species is a core of the redox cycling profile of anthracyclines. However, these molecular characteristics can be viewed as a double-edged sword acting not only on neoplastic cells but also on multiple cellular targets throughout the body. This phenomenon translates into anthracycline cardiotoxicity that is a serious problem in the growing population of paediatric and adult cancer survivors. Therefore, better understanding of cellular processes that operate within but also go beyond cardiomyocytes is a necessary step to develop more effective tools for the prevention and treatment of progressive and often severe cardiomyopathy experienced by otherwise successfully treated oncologic patients. In this review, we focus on oxidative stress-triggered cellular events such as DNA damage, senescence, and cell death implicated in anthracycline cardiovascular toxicity. The involvement of progenitor cells of cardiac and extracardiac origin as well as different cardiac cell types is discussed, pointing to molecular signals that impact on cell longevity and functional competence.

Antioxidant Therapeutic Strategies for Cardiovascular Conditions Associated with Oxidative Stress

Oxidative stress (OS) refers to the imbalance between the generation of reactive oxygen species (ROS) and the ability to scavenge these ROS by endogenous antioxidant systems, where ROS overwhelms the antioxidant capacity. Excessive presence of ROS results in irreversible damage to cell membranes, DNA, and other cellular structures by oxidizing lipids, proteins, and nucleic acids. Oxidative stress plays a crucial role in the pathogenesis of cardiovascular diseases related to hypoxia, cardiotoxicity and ischemia-reperfusion. Here, we describe the participation of OS in the pathophysiology of cardiovascular conditions such as myocardial infarction, anthracycline cardiotoxicity and congenital heart disease. This review focuses on the different clinical events where redox factors and OS are related to cardiovascular pathophysiology, giving to support for novel pharmacological therapies such as omega 3 fatty acids, non-selective betablockers and microRNAs.

Human carbonyl reductase 1 participating in intestinal first-pass drug metabolism is inhibited by fatty acids and acyl-CoAs

Human carbonyl reductase 1 (CBR1), a member of the short-chain dehydrogenase/reductase (SDR) superfamily, reduces a variety of carbonyl compounds including endogenous isatin, prostaglandin E₂ and 4-oxo-2-nonenal. It is also a major non-cytochrome P450 enzyme in the phase I metabolism of carbonyl-containing drugs, and is highly expressed in the intestine. In this study, we found that long-chain fatty acids and their CoA ester derivatives inhibit CBR1. Among saturated fatty acids, myristic, palmitic and stearic acids were inhibitory, and stearic acid was the most potent (IC₅₀ 9µM). Unsaturated fatty acids (oleic, elaidic, γ-linolenic and docosahexaenoic acids) and acyl-CoAs (palmitoyl-, stearoyl- and oleoyl-CoAs) were more potent inhibitors (IC₅₀ 1.0-2.5µM), and showed high inhibitory selectivity to CBR1 over its isozyme CBR3 and other SDR superfamily enzymes (DCXR and DHRS4) with CBR activity. The inhibition by these fatty acids and acyl-CoAs was competitive with respect to the substrate, showing the K_i values of 0.49-1.2µM. Site-directed mutagenesis of the substrate-binding residues of CBR1 suggested that the interactions between the fatty acyl chain and the enzyme's Met141 and Trp229 are important for the inhibitory selectivity. We also examined CBR1 inhibition by oleic acid in cellular levels: The fatty acid effectively inhibited CBR1-mediated 4-oxo-2-nonenal metabolism in colon cancer DLD1 cells and increased sensitivity to doxorubicin in the drug-resistant gastric cancer MKN45 cells that highly express CBR1. The results suggest a possible new food-drug interaction through inhibition of CBR1-mediated intestinal first-pass drug metabolism by dietary fatty acids.

Nutrition Modulation of Cardiotoxicity and Anticancer Efficacy Related to Doxorubicin Chemotherapy by Glutamine and ω-3 Polyunsaturated Fatty Acids

BACKGROUND

Doxorubicin (DOX) has been one of the most effective antitumor agents against a broad spectrum of malignancies. However, DOX-induced cardiotoxicity forms the major cumulative dose-limiting factor. Glutamine and ω-3 polyunsaturated fatty acids (PUFAs) are putatively cardioprotective during various stresses and/or have potential chemosensitizing effects during cancer chemotherapy.

METHODS

Antitumor activity and cardiotoxicity of DOX treatment were evaluated simultaneously in a MatBIII mammary adenocarcinoma tumor-bearing rat model treated with DOX (cumulative dose 12 mg/kg). Single or combined treatment of parenteral glutamine (0.35 g/kg) and ω-3 PUFAs (0.19 g/kg eicosapentaenoic acid and 0.18 g/kg docosahexaenoic acid) was administered every other day, starting 6 days before chemotherapy initiation until the end of study (day 50).

RESULTS

Glutamine alone significantly prevented DOX-related deterioration of cardiac function, reduced serum cardiac troponin I levels, and diminished cardiac lipid peroxidation while not affecting tumor inhibition kinetics. Single ω-3 PUFA treatment significantly enhanced antitumor activity of DOX associated with intensified tumoral oxidative stress and enhanced tumoral DOX concentration while not potentiating cardiac dysfunction or increasing cardiac oxidative stress. Intriguingly, providing glutamine and ω-3 PUFAs together did not consistently confer a greater benefit; conversely, individual benefits on cardiotoxicity and chemosensitization were mostly attenuated or completely lost when combined.

CONCLUSIONS

Our data demonstrate an interesting differentiality or even dichotomy in the response of tumor and host to single parenteral glutamine and ω-3 PUFA treatments. The intriguing glutamine × ω-3 PUFA interaction observed draws into question the common assumption that there are additive benefits of combinations of nutrients that are beneficial on an individual basis.

Cardioprotective effects of fish omega-3 fatty acids on doxorubicin-induced cardiotoxicity in rats

The aim of this study was to investigate the protective effects of fish omega-3 (n-3) fatty acids on doxorubicin (DOX)-induced acute cardiotoxicity. A total of 24 rats were divided into three groups: control, DOX-treated, and DOX treated with fish n-3 fatty acids. Control group received 0.4 ml/kg/day of saline intragastrically. The rats in the fish n-3 fatty acid-pretreated group were given 400 mg/kg/day fish n-3 fatty acids for 30 days by intragastric intubation. To induce acute cardiotoxicity, DOX (30 mg/kg) was injected intraperitoneally by a single dose and the rats were killed after 48 h. DOX treatment caused severe damage in heart tissues. Disorganization of myocardial muscle fibers, myofibrillar loss, and cardiotoxic myocardial fibers with cytoplasmic vacuoles were seen. Fish n-3 fatty acid-treated rats showed an improved histological appearance in the DOX-treated group. Our data indicate a significant reduction in the activity of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling in cardiomyocytes of the DOX-treated group with fish n-3 fatty acids therapy. The DOX-treated with fish n-3 fatty acids group showed a significant decrease in malondialdehyde levels, and an increase in superoxide dismutase and glutathione peroxidase activities in comparison with the DOX-treated group. This study showed that fish n-3 fatty acids may be a suitable cardioprotector against acute toxic effects of DOX.

Dietary trans fats enhance doxorubicin-induced cardiotoxicity in mice

This study investigated the combined effects of trans fat diet (TFD) and doxorubicin upon cardiac oxidative, inflammatory, and coagulatory stress. TFD increased trans fatty acid deposit in heart (P < 0.05), and decreased protein C and antithrombin-III activities in circulation (P < 0.05). TFD plus doxorubicin treatment elevated activities of plasminogen activator inhibitor-1, lactate dehydrogenase, and creatine phosphokinase (P < 0.05). This combination also raised xanthine oxidase activity, and enhanced cardiac levels of reactive oxygen species, interleukin (IL)-6, IL-10, tumor necrosis factor-alpha, and monocyte chemoattractant protein-1 than TFD or doxorubicin treatment alone (P < 0.05). TFD alone increased cardiac nuclear factor kappa B (NF-κB) activity (P < 0.05), but failed to affect expression of NF-κB and mitogen-activated protein kinase (MAPK) (P > 0.05). Doxorubicin treatment alone augmented cardiac activity, mRNA expression, and protein production of NF-κB and MAPK (P < 0.05). TFD plus doxorubicin treatment further upregulated cardiac expression of NF-κB p65, p-p38, and p-ERK1/2 (P < 0.05). These findings suggest that TFD exacerbates doxorubicin-induced cardiotoxicity.

Exploratory analysis on the use of statins with or without n-3 PUFA and major events in patients discharged for acute myocardial infarction: an observational retrospective study

Background

Combined treatment (CT) with statins and polyunsaturated fatty acids (n-3 PUFA) resulted in a reduction of death and major cardiovascular events when administered after a myocardial infarction (MI). However, recent data suggests that CT may be ineffective because patients are currently treated aggressively and the risk may not be further decreased. We aimed to study the prevalence and the results on major outcomes with CT among patients discharged with a MI in Italy.

Methodology/Principal findings

Retrospective cohort study that used linked hospital discharge, prescription databases and vital statistics containing information on 14,704 patients who were discharged for MI between 1/2003 and 12/2003 in 117 hospitals in Italy. All analyses were time-dependent and adjusted for major confounders. Sensibility and paired matched analysis were conducted to further verify main results. A total of 11,532 (78.4%) filled a prescription for a statin. Of these, 4302 (37.3%) were on CT. There were 45,528 patients/years of follow-up. As compared with statins alone, CT was associated with an adjusted higher survival rate (HR = 0.59 [0.52–0.66], p<0.001), survival free of atrial fibrillation (HR = 0.78 [0.71–0.86], p<0.001) and survival free of new heart failure development (HR = 0.81 [0.74–0.88], p<0.001), but not with re-infarction (HR = 0.94 [0.86–1.02], p<0.127). Clinically this means that between 2 to 3 fewer events for each 100 patients/year were obtained in the group under CT.

Conclusions/Significance

Among a representative sample of patients discharged with MI in Italy, we observed clinically significant synergism between the effects of statins and n-3 PUFA for most cardiovascular outcomes, including all cause mortality.

Dietary omega-3 supplementation exacerbates left ventricular dysfunction in an ovine model of anthracycline-induced cardiotoxicity

BACKGROUND

Cumulative dose-dependent nonischemic cardiomyopathy (NICM) remains a significant risk with the use of some chemotherapeutic agents. In this context, omega-3 polyunsaturated fatty acids (PUFA) have been investigated for their cardioprotective potential in rodent and in vitro models of anthracycline toxicity, with conflicting results. This study evaluated prophylactic omega-3 PUFA supplementation in a large-animal model of anthracycline-induced NICM.

METHODS AND RESULTS

Merino sheep were randomized to oral drenching with omega-3 PUFA (fish oil; n = 8) or olive oil placebo (n = 9) 3 weeks before commencing repeated intracoronary infusions of doxorubicin (DOX) to induce cardiac dysfunction. Cumulative DOX dose was 3.6 mg/kg. Drenching was continued for 12 weeks after final DOX exposure. Despite significant increases in tissue omega-3 PUFA levels (P < .05 vs placebo), omega-3-treated sheep displayed greater signs of anthracycline cardiotoxicity than placebo animals, consisting of left ventricular dilatation and a greater decline in ejection fraction (P < .05), although myocardial fibrosis burden was similar in both groups.

CONCLUSIONS

Dietary intake of omega-3 PUFA fails to prevent and may indeed exacerbate DOX-induced cardiotoxicity. Clinical use of omega-3 supplementation during chemotherapy should be deferred until more information is available regarding the mechanisms of interaction between fatty acids and the myocardium during anthracycline exposure.

Selective sensitization of tumors to chemotherapy by marine-derived lipids: a review

Despite great improvements, a significant proportion of cancer patients still die, mainly because of the development of metastases. At this stage, current treatments still rely heavily on conventional chemotherapy for most cancers. The efficacy of chemotherapy is dose-dependent, which is limited by toxicity to non-tumor tissues, as a result of its poor tumor selectivity. To improve survival length and preserve quality of life, the challenge is to develop approaches aimed at increasing chemotherapy toxicity to tumor tissue while not affecting non-tumor tissues. Marine-derived lipids, docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), have the potential to differentially sensitize tissues to chemotherapy. These lipids enhance the cytotoxicity of 15 anticancer drugs (antimetabolites, alkylating or intercalating agents, microtubule stabilizers, Abl tyrosine kinase inhibitor and arsenic trioxide) to a variety of cancer cell lines or tumors in animals, used as models for breast, prostate, colonic, lung, cervical, ovarian cancers, neuroblastomas, leukemia or lymphomas. However, DHA and EPA do not sensitize non-tumor tissues to anticancer drugs, which suggests that the effect of these lipids is tumor selective. Two phase II clinical trials already support these results, and randomized, phase III trials are ongoing. In this review, we discuss the double-faceted properties of these lipids, and then focus on their potential for transfer to the patient in the light of current therapeutic strategies. Should their beneficial effects be confirmed, the consequences could be considerable by opening up the prospect of systematic supplementation during cancer treatment, a significant shift in current cancer therapeutic paradigms.

DHA derivatives of fish oil as dietary supplements: a nutrition-based drug discovery approach for therapies to prevent metabolic cardiotoxicity

INTRODUCTION

During the early 1970s, Danish physicians Jorn Dyerberg and colleagues observed that Greenland Eskimos consuming fatty fishes exhibited low incidences of heart disease. Fish oil is now one of the most commonly consumed dietary supplements. In 2004, concentrated fish oil was approved as a drug by the FDA for the treatment of hyperlipidemia. Fish oil contains two major omega-3 fatty acids: eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). With advancements in lipid concentration and purification techniques, EPA- or DHA-enriched products are now commercially available, and the availability of these components in isolation allows their individual effects to be examined. Newly synthesized derivatives and endogenously discovered metabolites of DHA exhibit therapeutic utility for obesity, metabolic syndrome and cardiovascular disease.

AREAS COVERED

This review summarizes our current knowledge on the distinct effects of EPA and DHA to prevent metabolic syndrome and reduce cardiotoxicity risk. Since EPA is an integral component of fish oil, we will briefly review EPA effects, but our main theme will be to summarize effects of the DHA derivatives that are available today. We focus on using nutrition-based drug discovery to explore the potential of DHA derivatives for the treatment of obesity, metabolic syndrome and cardiovascular diseases.

EXPERT OPINION

The safety and efficacy evaluation of DHA derivatives will provide novel biomolecules for the drug discovery arsenal. Novel nutritional-based drug discoveries of DHA derivatives or metabolites may provide realistic and alternative strategies for the treatment of metabolic and cardiovascular disease.

Omega-3 fatty acids and cardiovascular disease: effects on risk factors, molecular pathways, and clinical events

We reviewed available evidence for cardiovascular effects of n-3 polyunsaturated fatty acid (PUFA) consumption, focusing on long chain (seafood) n-3 PUFA, including their principal dietary sources, effects on physiological risk factors, potential molecular pathways and bioactive metabolites, effects on specific clinical endpoints, and existing dietary guidelines. Major dietary sources include fatty fish and other seafood. n-3 PUFA consumption lowers plasma triglycerides, resting heart rate, and blood pressure and might also improve myocardial filling and efficiency, lower inflammation, and improve vascular function. Experimental studies demonstrate direct anti-arrhythmic effects, which have been challenging to document in humans. n-3 PUFA affect a myriad of molecular pathways, including alteration of physical and chemical properties of cellular membranes, direct interaction with and modulation of membrane channels and proteins, regulation of gene expression via nuclear receptors and transcription factors, changes in eicosanoid profiles, and conversion of n-3 PUFA to bioactive metabolites. In prospective observational studies and adequately powered randomized clinical trials, benefits of n-3 PUFA seem most consistent for coronary heart disease mortality and sudden cardiac death. Potential effects on other cardiovascular outcomes are less-well-established, including conflicting evidence from observational studies and/or randomized trials for effects on nonfatal myocardial infarction, ischemic stroke, atrial fibrillation, recurrent ventricular arrhythmias, and heart failure. Research gaps include the relative importance of different physiological and molecular mechanisms, precise dose-responses of physiological and clinical effects, whether fish oil provides all the benefits of fish consumption, and clinical effects of plant-derived n-3 PUFA. Overall, current data provide strong concordant evidence that n-3 PUFA are bioactive compounds that reduce risk of cardiac death. National and international guidelines have converged on consistent recommendations for the general population to consume at least 250 mg/day of long-chain n-3 PUFA or at least 2 servings/week of oily fish.