Towards the use of localised delivery strategies to counteract cancer therapy-induced cardiotoxicities

Nanoparticle Based Cardiac Specific Drug Delivery

Heart failure secondary to myocardial injuries is a leading cause of death worldwide. Recently, a growing number of novel therapies have emerged for injured myocardium repairment. However, delivering therapeutic agents specifically to the injured heart remains a significant challenge. Nanoparticles are the most commonly used vehicles for targeted drug delivery. Various nanoparticles have been synthesized to deliver drugs and other therapeutic molecules to the injured heart via passive or active targeting approaches, and their targeting specificity and therapeutic efficacies have been investigated. Here, we summarized nanoparticle-based, cardiac-specific drug delivery systems, their potency for treating heart diseases, and the mechanisms underlying these cardiac-targeting strategies. We also discussed the clinical studies that have employed nanoparticle-based cardiac-specific drug delivery.

The Implication of Low Dose Dimethyl Sulfoxide on Mitochondrial Function and Oxidative Damage in Cultured Cardiac and Cancer Cells

Although numerous studies have demonstrated the biological and multifaceted nature of dimethyl sulfoxide (DMSO) across different in vitro models, the direct effect of "non-toxic" low DMSO doses on cardiac and cancer cells has not been clearly explored. In the present study, H9c2 cardiomyoblasts and MCF-7 breast cancer cells were treated with varying concentrations of DMSO (0.001-3.7%) for 6 days. Here, DMSO doses < 0.5% enhanced the cardiomyoblasts respiratory control ratio and cellular viability relative to the control cells. However, 3.7% DMSO exposure enhanced the rate of apoptosis, which was driven by mitochondrial dysfunction and oxidative stress in the cardiomyoblasts. Additionally, in the cancer cells, DMSO (≥0.009) led to a reduction in the cell's maximal respiratory capacity and ATP-linked respiration and turnover. As a result, the reduced bioenergetics accelerated ROS production whilst increasing early and late apoptosis in these cells. Surprisingly, 0.001% DMSO exposure led to a significant increase in the cancer cells proliferative activity. The latter, therefore, suggests that the use of DMSO, as a solvent or therapeutic compound, should be applied with caution in the cancer cells. Paradoxically, in the cardiomyoblasts, the application of DMSO (≤0.5%) demonstrated no cytotoxic or overt therapeutic benefits.

The role of anti-inflammatory drugs and nanoparticle-based drug delivery models in the management of ischemia-induced heart failure

Ongoing advancements in the treatment of acute myocardial infarction (MI) have significantly decreased MI related mortality. Consequently, the number of patients experiencing post-MI heart failure (HF) has continued to rise. Infarction size and the extent of left ventricular (LV) remodeling are largely determined by the extent of ischemia at the time of myocardial injury. In the setting of MI or acute phase of post-MI LV remodeling, anti-inflammatory drugs including intravenous immunoglobulin (IVIG) and Pentoxifylline have shown potential efficacy in preventing post-MI remodeling in-vitro and in some clinical trials. However, systemic administration of anti-inflammatory drugs are not without their off-target side effects. Herein, we explore the clinical feasibility of targeted myocardial delivery of anti-inflammatory drugs via biodegradable polymers, liposomes, hydrogels, and nano-particle based drug delivery models (NDDM) based on existing pre-clinical and clinical models. We summarize the barriers to clinical application of targeted anti-inflammatory delivery post-MI, including challenges in achieving sufficient retention and distribution, as well as the potential need for multiple dosing. Collectively, we suggest that localized delivery of anti-inflammatory agents to the myocardium using NDDM is a promising approach for successful treatment of ischemic HF. Future studies will be instrumental in determining the most effective target and delivery modalities for orchestrating NDDM-mediated treatment of HF.

Nanomedicine in Oncocardiology: Contribution and Perspectives of Preclinical Studies

Cancer and cardiovascular diseases are the leading causes of death and morbidity worldwide. Strikingly, cardiovascular disorders are more common and more severe in cancer patients than in the general population, increasing incidence rates. In this context, it is vital to consider the anticancer efficacy of a treatment and the devastating heart complications it could potentially cause. Oncocardiology has emerged as a promising medical and scientific field addressing these aspects from different angles. Interestingly, nanomedicine appears to have great promise in reducing the cardiotoxicity of anticancer drugs, maintaining or even enhancing their efficacy. Several studies have shown the benefits of nanocarriers, although with some flaws when considering the concept of oncocardiology. Herein, we discuss how preclinical studies should be designed as closely as possible to clinical protocols, considering various parameters intrinsic to the animal models used and the experimental protocols. The sex and age of the animals, the size and location of the tumors, the doses of the nanoformulations administered, and the acute vs. the long-term effects of treatments are essential aspects. We also discuss the perspectives offered by non-invasive imaging techniques to simultaneously assess both the anticancer effects of treatment and its potential impact on the heart. The overall objective is to accelerate the development and validation of nanoformulations through high-quality preclinical studies reproducing the clinical conditions.

Resveratrol significantly improves cell survival in comparison to dexrazoxane and carvedilol in a h9c2 model of doxorubicin induced cardiotoxicity

Cancer is one of the leading causes of deaths worldwide with 18.1 million deaths per year. Although there have been significant advances in anti-cancer therapies, they can often result in side effects with cardiovascular complications being the most severe. Dexrazoxane is the only currently approved treatment for prevention of anthracycline induced cardiotoxicity but there are concerns about its use due to the development of secondary malignancies and myelodysplastic syndrome. Additionally, it is only recommended in patients who are due to receive a total cumulative dose of 300 mg/m² of doxorubicin or 540 mg/m² of epirubicin. Thus, there exists an urgent need to develop new therapeutic strategies to counteract anthracycline induced cardiotoxicity. The h9c2 cardiomyoblast was investigated for its differentiation capacity and used to screen and compare promising prophylactics for doxorubicin induced cardiotoxicity. The half maximal inhibitory concentration of doxorubicin was determined in differentiated h9c2 cells after 24 h of exposure, to establish a model for drug screening. Cells were treated with dexrazoxane, resveratrol, and carvedilol either 3 h or 24 h prior to doxorubicin treatment. The ability of these cardioprotectants to prevent cardiotoxicity was analysed using the cck-8 cell viability assay and the dichlorofluorescin diacetate (DCFDA) reactive oxygen species (ROS) assay. There was no significant increase in survival in treatment groups after 3 h, however, at 24 h, resveratrol significantly improved survival compared to all other groups (p < 0.05). Additionally, dexrazoxane and resveratrol significantly decreased ROS formation at 3 h (p < 0.05) and all groups significantly decreased ROS production at 24 h (p < 0.001). This work is the first comparison of these cardioprotectants and suggests that resveratrol may be a more effective treatment in the prevention of anthracycline induced cardiotoxicity, compared to dexrazoxane and carvedilol. However, further work will be needed in order to decipher the exact mechanism and potential of this drug in the clinic.