Labile redox-active iron ions have been implicated in various neurodegenerative disorders, including the Parkinson's disease (PD). Iron chelation has been successfully used in clinical practice to manage iron overload in diseases such as thalassemia major; however, the use of conventional iron chelators in pathological states without systemic iron overload remains at the preclinical investigative level and is complicated by the risk of adverse outcomes due to systemic iron depletion. In this study, we examined three clinically-used chelators, namely, desferrioxamine, deferiprone and deferasirox and compared them with experimental agent salicylaldehyde isonicotinoyl hydrazone (SIH) and its boronate-masked prochelator BSIH for protection of differentiated PC12 cells against the toxicity of catecholamines 6-hydroxydopamine and dopamine and their oxidation products. All the assayed chelating agents were able to significantly reduce the catecholamine toxicity in a dose-dependent manner. Whereas hydrophilic chelator desferrioxamine exerted protection only at high and clinically unachievable concentrations, deferiprone and deferasirox significantly reduced the catecholamine neurotoxicity at concentrations that are within their plasma levels following standard dosage. SIH was the most effective iron chelator to protect the cells with the lowest own toxicity of all the assayed conventional chelators. This favorable feature was even more pronounced in prochelator BSIH that does not chelate iron unless its protective group is cleaved in disease-specific oxidative stress conditions. Hence, this study demonstrated that while iron chelation may have general neuroprotective potential against catecholamine auto-oxidation and toxicity, SIH and BSIH represent promising lead molecules and warrant further studies in more complex animal models.

• MeSH
• PC12 Cells MeSH
• Iron Chelating Agents * pharmacology   MeSH
• Deferasirox pharmacology   MeSH
• Deferiprone pharmacology   MeSH
• Deferoxamine pharmacology   MeSH
• Dopamine pharmacology   MeSH
• Catecholamines pharmacology   MeSH
• Rats MeSH
• Oxidative Stress MeSH
• Oxidopamine pharmacology   MeSH
• Iron Overload * MeSH
• Iron pharmacology   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• Iron Chelating Agents * MeSH
• Deferasirox MeSH
• Deferiprone MeSH
• Deferoxamine MeSH
• Dopamine MeSH
• Catecholamines MeSH
• Oxidopamine MeSH
• Iron MeSH

Cardiovascular diseases are a leading cause of morbidity and mortality in most developed countries of the world. Pharmaceuticals, illicit drugs, and toxins can significantly contribute to the overall cardiovascular burden and thus deserve attention. The present article is a systematic overview of drugs that may induce distinct cardiovascular toxicity. The compounds are classified into agents that have significant effects on the heart, blood vessels, or both. The mechanism(s) of toxic action are discussed and treatment modalities are briefly mentioned in relevant cases. Due to the large number of clinically relevant compounds discussed, this article could be of interest to a broad audience including pharmacologists and toxicologists, pharmacists, physicians, and medicinal chemists. Particular emphasis is given to clinically relevant topics including the cardiovascular toxicity of illicit sympathomimetic drugs (e.g., cocaine, amphetamines, cathinones), drugs that prolong the QT interval, antidysrhythmic drugs, digoxin and other cardioactive steroids, beta-blockers, calcium channel blockers, female hormones, nonsteroidal anti-inflammatory, and anticancer compounds encompassing anthracyclines and novel targeted therapy interfering with the HER2 or the vascular endothelial growth factor pathway.

• Keywords
• dysrhythmia, heart failure, hypertension, myocardial infarction, stroke,
• MeSH
• Alkaloids adverse effects   MeSH
• Amphetamines adverse effects   MeSH
• Anti-Arrhythmia Agents adverse effects   MeSH
• Anti-Inflammatory Agents, Non-Steroidal adverse effects   MeSH
• Adrenergic beta-Antagonists adverse effects   MeSH
• Calcium Channel Blockers adverse effects   MeSH
• Stroke drug therapy   MeSH
• Digoxin adverse effects   MeSH
• Hormones adverse effects   MeSH
• Cardiovascular Diseases chemically induced   drug therapy   MeSH
• Cardiovascular System drug effects   MeSH
• Cocaine adverse effects   MeSH
• Humans MeSH
• Antineoplastic Agents adverse effects   MeSH
• Heart Rate drug effects   MeSH
• Steroids adverse effects   MeSH
• Vascular Endothelial Growth Factor A MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• Alkaloids MeSH
• Amphetamines MeSH
• Anti-Arrhythmia Agents MeSH
• Anti-Inflammatory Agents, Non-Steroidal MeSH
• Adrenergic beta-Antagonists MeSH
• Calcium Channel Blockers MeSH
• cathinone MeSH Browser
• Digoxin MeSH
• Hormones MeSH
• Cocaine MeSH
• Antineoplastic Agents MeSH
• Steroids MeSH
• Vascular Endothelial Growth Factor A MeSH

Oxidative stress is a common denominator of numerous cardiovascular disorders. Free cellular iron catalyzes the formation of highly toxic hydroxyl radicals, and iron chelation may thus be an effective therapeutic approach. However, using classical iron chelators in diseases without iron overload poses risks that necessitate more advanced approaches, such as prochelators that are activated to chelate iron only under disease-specific oxidative stress conditions. In this study, three cell-membrane-permeable iron chelators (clinically used deferasirox and experimental SIH and HAPI) and five boronate-masked prochelator analogs were evaluated for their ability to protect cardiac cells against oxidative injury induced by hydrogen peroxide. Whereas the deferasirox-derived agents TIP and TRA-IMM displayed negligible protection and even considerable toxicity, the aroylhydrazone prochelators BHAPI and BSIH-PD provided significant cytoprotection and displayed lower toxicity after prolonged cellular exposure compared to their parent chelators HAPI and SIH, respectively. Overall, the most favorable properties in terms of protective efficiency and low inherent cytotoxicity were observed with the aroylhydrazone prochelator BSIH. BSIH efficiently protected both H9c2 rat cardiomyoblast-derived cells and isolated primary rat cardiomyocytes against hydrogen peroxide-induced mitochondrial and lysosomal dysregulation and cell death. At the same time, BSIH was nontoxic at concentrations up to its solubility limit (600 μM) and in 72-h incubation. Hence, BSIH merits further investigation for prevention and/or treatment of cardiovascular disorders associated with a known (or presumed) component of oxidative stress.

• Keywords
• BSIH, Deferasirox, Free radicals, ICL670A, Iron chelation, Prochelator, Salicylaldehyde isonicotinoyl hydrazone,
• MeSH
• Aldehydes chemistry   pharmacology   MeSH
• Apoptosis drug effects   MeSH
• Benzoates chemistry   pharmacology   MeSH
• Cell Line MeSH
• Iron Chelating Agents chemistry   pharmacology   MeSH
• Cytoprotection * MeSH
• Deferasirox MeSH
• Hydrazones chemistry   pharmacology   MeSH
• Myocytes, Cardiac drug effects   physiology   MeSH
• Rats MeSH
• Boronic Acids chemistry   pharmacology   MeSH
• Isonicotinic Acids chemistry   pharmacology   MeSH
• Membrane Potential, Mitochondrial drug effects   MeSH
• Oxidative Stress drug effects   MeSH
• Cell Membrane Permeability drug effects   MeSH
• Hydrogen Peroxide metabolism   MeSH
• Rats, Wistar MeSH
• Semicarbazones chemistry   pharmacology   MeSH
• Boron Compounds chemistry   pharmacology   MeSH
• Mitochondria, Heart drug effects   physiology   MeSH
• Triazoles chemistry   pharmacology   MeSH
• Iron chemistry   metabolism   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Comparative Study MeSH
• Names of Substances
• (isonicotinic acid (2-(4,4,5,5-tetramethyl-(1,3,2)dioxaborolan-2-yl)benzylidene)hydrazide) MeSH Browser
• Aldehydes MeSH
• Benzoates MeSH
• Iron Chelating Agents MeSH
• Deferasirox MeSH
• Hydrazones MeSH
• Boronic Acids MeSH
• Isonicotinic Acids MeSH
• N'-(1-(2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyloxy)phenyl)ethylidene)isonicotinohydrazide MeSH Browser
• Hydrogen Peroxide MeSH
• salicylaldehyde isonicotinoyl hydrazone MeSH Browser
• Semicarbazones MeSH
• Boron Compounds MeSH
• Triazoles MeSH
• Iron MeSH

SIGNIFICANCE: Anthracyclines (doxorubicin, daunorubicin, or epirubicin) rank among the most effective anticancer drugs, but their clinical usefulness is hampered by the risk of cardiotoxicity. The most feared are the chronic forms of cardiotoxicity, characterized by irreversible cardiac damage and congestive heart failure. Although the pathogenesis of anthracycline cardiotoxicity seems to be complex, the pivotal role has been traditionally attributed to the iron-mediated formation of reactive oxygen species (ROS). In clinics, the bisdioxopiperazine agent dexrazoxane (ICRF-187) reduces the risk of anthracycline cardiotoxicity without a significant effect on response to chemotherapy. The prevailing concept describes dexrazoxane as a prodrug undergoing bioactivation to an iron-chelating agent ADR-925, which may inhibit anthracycline-induced ROS formation and oxidative damage to cardiomyocytes. RECENT ADVANCES: A considerable body of evidence points to mitochondria as the key targets for anthracycline cardiotoxicity, and therefore it could be also crucial for effective cardioprotection. Numerous antioxidants and several iron chelators have been tested in vitro and in vivo with variable outcomes. None of these compounds have matched or even surpassed the effectiveness of dexrazoxane in chronic anthracycline cardiotoxicity settings, despite being stronger chelators and/or antioxidants. CRITICAL ISSUES: The interpretation of many findings is complicated by the heterogeneity of experimental models and frequent employment of acute high-dose treatments with limited translatability to clinical practice. FUTURE DIRECTIONS: Dexrazoxane may be the key to the enigma of anthracycline cardiotoxicity, and therefore it warrants further investigation, including the search for alternative/complementary modes of cardioprotective action beyond simple iron chelation.

• MeSH
• Antioxidants chemistry   pharmacology   MeSH
• Anthracyclines adverse effects   chemistry   pharmacology   MeSH
• Chelating Agents adverse effects   chemistry   pharmacology   MeSH
• Cardiotonic Agents adverse effects   chemistry   pharmacology   MeSH
• Metals adverse effects   MeSH
• Humans MeSH
• Myocardium metabolism   MeSH
• Oxidation-Reduction MeSH
• Oxidative Stress * MeSH
• Antineoplastic Agents adverse effects   chemistry   pharmacology   MeSH
• Razoxane adverse effects   chemistry   pharmacology   MeSH
• Reactive Oxygen Species metabolism   MeSH
• Signal Transduction * MeSH
• Heart drug effects   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH
• Names of Substances
• Antioxidants MeSH
• Anthracyclines MeSH
• Chelating Agents MeSH
• Cardiotonic Agents MeSH
• Metals MeSH
• Antineoplastic Agents MeSH
• Razoxane MeSH
• Reactive Oxygen Species MeSH