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
• buňky PC12 MeSH
• chelátory železa * farmakologie   MeSH
• deferasirox farmakologie   MeSH
• deferipron farmakologie   MeSH
• deferoxamin farmakologie   MeSH
• dopamin farmakologie   MeSH
• katecholaminy farmakologie   MeSH
• krysa rodu Rattus MeSH
• oxidační stres MeSH
• oxidopamin farmakologie   MeSH
• přetížení železem * MeSH
• železo farmakologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• chelátory železa * MeSH
• deferasirox MeSH
• deferipron MeSH
• deferoxamin MeSH
• dopamin MeSH
• katecholaminy MeSH
• oxidopamin MeSH
• železo MeSH

Catecholamines may undergo iron-promoted oxidation resulting in formation of reactive intermediates (aminochromes) capable of redox cycling and reactive oxygen species (ROS) formation. Both of them induce oxidative stress resulting in cellular damage and death. Iron chelation has been recently shown as a suitable tool of cardioprotection with considerable potential to protect cardiac cells against catecholamine-induced cardiotoxicity. However, prolonged exposure of cells to classical chelators may interfere with physiological iron homeostasis. Prochelators represent a more advanced approach to decrease oxidative injury by forming a chelating agent only under the disease-specific conditions associated with oxidative stress. Novel prochelator (lacking any iron chelating properties) BHAPI [(E)-Ń-(1-(2-((4-(4,4,5,5-tetramethyl-1,2,3-dioxoborolan-2-yl)benzyl)oxy)phenyl)ethylidene) isonicotinohydrazide] is converted by ROS to active chelator HAPI with strong iron binding capacity that efficiently inhibits iron-catalyzed hydroxyl radical generation. Our results confirmed redox activity of oxidation products of catecholamines isoprenaline and epinephrine, that were able to activate BHAPI to HAPI that chelates iron ions inside H9c2 cardiomyoblasts. Both HAPI and BHAPI were able to efficiently protect the cells against intracellular ROS formation, depletion of reduced glutathione and toxicity induced by catecholamines and their oxidation products. Hence, both HAPI and BHAPI have shown considerable potential to protect cardiac cells by both inhibition of deleterious catecholamine oxidation to reactive intermediates and prevention of ROS-mediated cardiotoxicity.

• Klíčová slova
• BHAPI, Cardiotoxicity, Catecholamines, HAPI, Iron chelation, Prochelator,
• MeSH
• adrenalin antagonisté a inhibitory   toxicita   MeSH
• biokatalýza MeSH
• buněčné linie MeSH
• chelátory železa farmakologie   MeSH
• glutathion metabolismus   MeSH
• hydroxylový radikál metabolismus   MeSH
• isoprenalin antagonisté a inhibitory   toxicita   MeSH
• kardiotonika farmakologie   MeSH
• katecholaminy antagonisté a inhibitory   toxicita   MeSH
• krysa rodu Rattus MeSH
• kyseliny boronové farmakologie   MeSH
• lidé MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• oxidační stres účinky léků   MeSH
• prekurzory léčiv farmakologie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• semikarbazony farmakologie   MeSH
• sloučeniny boru farmakologie   MeSH
• železo chemie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• adrenalin MeSH
• chelátory železa MeSH
• glutathion MeSH
• hydroxylový radikál MeSH
• isoprenalin MeSH
• kardiotonika MeSH
• katecholaminy MeSH
• kyseliny boronové MeSH
• N'-(1-(2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzyloxy)phenyl)ethylidene)isonicotinohydrazide MeSH Prohlížeč
• prekurzory léčiv MeSH
• reaktivní formy kyslíku MeSH
• semikarbazony MeSH
• sloučeniny boru MeSH
• železo MeSH

Free cellular iron catalyzes the formation of toxic hydroxyl radicals and therefore chelation of iron could be a promising therapeutic approach in pathological states associated with oxidative stress. Salicylaldehyde isonicotinoyl hydrazone (SIH) is a strong intracellular iron chelator with well documented potential to protect against oxidative damage both in vitro and in vivo. Due to the short biological half-life of SIH and risk of toxicity due to iron depletion, boronate prochelator BSIH has been designed. BSIH cannot bind iron until it is activated by certain reactive oxygen species to active chelator SIH. The aim of this study was to examine the toxicity and cytoprotective potential of BSIH, SIH, and their decomposition products against hydrogen peroxide-induced injury of H9c2 cardiomyoblast cells. Using HPLC, we observed that salicylaldehyde was the main decomposition products of SIH and BSIH, although a small amount of salicylic acid was also detected. In the case of BSIH, the concentration of formed salicylaldehyde consistently exceeded that of SIH. Isoniazid and salicylic acid were not toxic nor did they provide any antioxidant protective effect in H9c2 cells. In contrast, salicylaldehyde was able to chelate intracellular iron and significantly preserve cellular viability and mitochondrial inner membrane potential induced by hydrogen peroxide. However it was consistently less effective than SIH. The inherent toxicities of salicylaldehyde and SIH were similar. Hence, although SIH - the active chelating agent formed following the BSIH activation - undergoes rapid hydrolysis, its principal decomposition product salicylaldehyde accounts markedly for both cytoprotective and toxic properties.

• Klíčová slova
• Boronyl salicylaldehyde isonicotinoyl hydrazone (BSIH), Iron chelation, Prochelator, Salicylaldehyde, Salicylaldehyde isonicotinoyl hydrazone (SIH),
• MeSH
• aldehydy farmakologie   toxicita   MeSH
• buněčné linie MeSH
• chelátory železa farmakologie   toxicita   MeSH
• hydrazony farmakologie   toxicita   MeSH
• krysa rodu Rattus MeSH
• kyseliny boronové farmakologie   toxicita   MeSH
• kyseliny isonikotinové farmakologie   toxicita   MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• myoblasty srdeční účinky léků   metabolismus   MeSH
• oxidační stres účinky léků   MeSH
• peroxid vodíku toxicita   MeSH
• poločas MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• viabilita buněk účinky léků   MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• železo metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• (isonicotinic acid (2-(4,4,5,5-tetramethyl-(1,3,2)dioxaborolan-2-yl)benzylidene)hydrazide) MeSH Prohlížeč
• aldehydy MeSH
• chelátory železa MeSH
• hydrazony MeSH
• kyseliny boronové MeSH
• kyseliny isonikotinové MeSH
• peroxid vodíku MeSH
• reaktivní formy kyslíku MeSH
• salicylaldehyde isonicotinoyl hydrazone MeSH Prohlížeč
• železo MeSH

Salicylaldehyde isonicotinoyl hydrazone (SIH) is an intracellular iron chelator with well documented potential to protect against oxidative injury both in vitro and in vivo. However, it suffers from short biological half-life caused by fast hydrolysis of the hydrazone bond. Recently, a concept of boronate prochelators has been introduced as a strategy that might overcome these limitations. This study presents two complementary analytical methods for detecting the prochelator-boronyl salicylaldehyde isonicotinoyl hydrazone-BSIH along with its active metal-binding chelator SIH in different solution matrices and concentration ranges. An LC-UV method for determination of BSIH and SIH in buffer and cell culture medium was validated over concentrations of 7-115 and 4-115 μM, respectively, and applied to BSIH activation experiments in vitro. An LC-MS assay was validated for quantification of BSIH and SIH in plasma over the concentration range of 0.06-23 and 0.24-23 μM, respectively, and applied to stability studies in plasma in vitro as well as analysis of plasma taken after i.v. administration of BSIH to rats. A Zorbax-RP bonus column and mobile phases containing either phosphate buffer with EDTA or ammonium formate and methanol/acetonitrile mixture provided suitable conditions for the LC-UV and LC-MS analysis, respectively. Samples were diluted or precipitated with methanol prior to analysis. These separative analytical techniques establish the first validated protocols to investigate BSIH activation by hydrogen peroxide in multiple matrices, directly compare the stabilities of the prochelator and its chelator in plasma, and provide the first basic pharmacokinetic data of this prochelator. Experiments reveal that BSIH is stable in all media tested and is partially converted to SIH by H2O2. The observed integrity of BSIH in plasma samples from the in vivo study suggests that the concept of prochelation might be a promising strategy for further development of aroylhydrazone cytoprotective agents.

• Klíčová slova
• Aroylhydrazone, Boronyl salicylaldehyde isonicotinoyl hydrazone, Pharmacokinetics, Prochelator salicylaldehyde isonicotinoyl hydrazone, Stability,
• MeSH
• aldehydy analýza   krev   MeSH
• chelátory analýza   MeSH
• chromatografie kapalinová metody   MeSH
• hmotnostní spektrometrie metody   MeSH
• hydrazony analýza   krev   MeSH
• kultivační média chemie   MeSH
• kyseliny boronové analýza   krev   MeSH
• kyseliny isonikotinové analýza   krev   MeSH
• molekulární struktura MeSH
• potkani Wistar MeSH
• referenční standardy MeSH
• senzitivita a specificita MeSH
• spektrofotometrie ultrafialová metody   MeSH
• stabilita léku MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• Názvy látek
• (isonicotinic acid (2-(4,4,5,5-tetramethyl-(1,3,2)dioxaborolan-2-yl)benzylidene)hydrazide) MeSH Prohlížeč
• aldehydy MeSH
• chelátory MeSH
• hydrazony MeSH
• kultivační média MeSH
• kyseliny boronové MeSH
• kyseliny isonikotinové MeSH
• salicylaldehyde isonicotinoyl hydrazone MeSH Prohlížeč