Disease relevance of SQ 2113

• TPEN, but not pyrithione, was intrinsically toxic at high concentrations, likely due to excessive chelation of [Zn(2+)](i), as this intrinsic toxicity was reduced by prior addition of extracellular Zn(2+) [1].
• Studies on cytotoxic and genotoxic effects of N-hydroxypyridine-2-thione (Omadine) in L5178Y mouse lymphoma cells [2].
• Growth and survival of Klebsiella pneumoniae in the presence of pyrithione [3].
• AIMS: The aim of this study was to determine whether passaging Pseudomonas aeruginosa PAO1 with sub-MICs of the pyrithione biocides results in both the induction of decreased susceptibility towards these antimicrobials and associated outer membrane profile changes [4].
• Pyrithione was active against a range of micro-organisms, the most resistant being Gram-negative bacteria [5].

High impact information on SQ 2113

• On the basis of these in vitro studies, we believe that the use of omadine in particular and iron chelators in general, by themselves or as cell cycle-recruiting agents together with standard cell cycle specific drugs, is an approach to the treatment of cancer worth further investigation [6].
• Oxidative stress, induced by addition of either doxorubicin or 2-mercaptopyridine N-oxide, resulted in a significant decrease in the extent of ionophore-stimulated calpain activity of both the fluorescent compound and the endogenous substrates compared with control, normoxic conditions [7].
• Treatment of H19-7 cells with 10 muM of zinc plus zinc ionophore, pyrithione, led to increased phosphorylation of Akt at Ser-473/Thr-308 and increased Akt kinase activity [8].
• Zn2+, in the presence of the Zn2+ ionophore pyrithione, caused rapid inhibition of MER rosetting at concentrations which induce the translocation and activation of PKC [9].
• Intracellular accumulation of Zn2+ induced by the combined application of pyrithione (5 microM), a Zn2+ ionophore, and Zn2+ (10 microM) caused cell death and activated JNK and ERK, but not p38 MAPK [10].

Chemical compound and disease context of SQ 2113

• The following increasing order of toxicity was obtained: Cd < Zn < Cu < Diuron < Zn pyrithione < Irgarol 1051 [11].
• Iron (5 microM), attached to ligands that either restrict iron to the extracellular space (ADP) or facilitate the entry of iron into myocytes (omadine, tropolone), was infused during the last 3 min of ischemia and the first 4 min of reperfusion [12].

Biological context of SQ 2113

• Conversely, increasing labile Zn by pretreatment with Zn plus pyrithione suppressed both spontaneous DNA fragmentation and that induced by the potent apoptosis-induced agents colchicine and dexamethasone [13].
• In the present study, we investigated the role of intracellular Zn level in the induction of apoptosis in human leukemia cells (HL-60 cells) using a Zn ionophore [pyrithione (Py)] [14].
• Hypoxia-induced vasoconstrictions were abolished by preincubation with NF-kappaB inhibitors, pyrrolidine dithiocarbamate (100 microM) or pyrithione (10 microM) [15].
• Also, a Zn2+ ionophore, pyrithione, potentiated the ADP-induced platelet aggregation and this potentiation was blocked by TPEN [16].
• Indirect estimation of degradation time for zinc pyrithione and copper pyrithione in seawater [17].

Anatomical context of SQ 2113

• We have investigated a newer agent, 2-mercaptopyridine-N-oxide (Merc) at our institution which unlike oxine, allows us to label leukocytes in plasma, using a simple kit procedure [18].
• Zinquin labelled human chronic-lymphocytic-leukaemia lymphocytes, rat splenocytes and thymocytes with a weak diffuse fluorescence that was quenched when intracellular Zn was chelated with NNN'N'-tetrakis-(2-pyridylmethyl)ethylenediamine (TPEN) and was greatly intensified by pretreatment of cells with the Zn ionophore pyrithione and exogenous Zn [13].
• We used the Zn(2+)-selective ionophore pyrithione to directly increase [Zn(2+)](i) in both neurons and astrocytes [19].
• Current-voltage analysis demonstrates that the depolarization is accompanied by a decrease in membrane electrical conductance in a manner consistent with inhibition of the primary proton pump and inconsistent with a mode of action of pyrithione on plasma membrane ion channels [20].
• Analysis of the intracellular zinc level upon pyrithione and (+/-)-(E)-methyl-2-[(E)-hydroxyimino]-5-nitro-6-methoxy-3-hexeneamide (NOR-1) treatment revealed no differences between S100A9-deficient and wildtype neutrophils [21].

Associations of SQ 2113 with other chemical compounds

• Indeed, some delay was essential for neuroprotection with pyrithione, as co-administration of pyrithione together with extracellular Zn(2+) increased levels of [Zn(2+)](i) and cell death compared to the levels induced by Zn(2+) alone [1].
• Zinc-induced apoptosis in C6 cells was independent of major signaling pathways (protein kinase C, mitogen activated protein kinase and guanylate cyclase) and protein synthesis, but was increased by facilitating zinc uptake with the ionophore pyrithione [22].
• Time-course studies of cell viability and thymidine incorporation demonstrated that the inhibitory effect of omadine was attributable to cell killing while for ADR-529 and SAG-15 there were both cytostatic and cytotoxic effects [23].
• Human leukocytes and platelets were labeled in plasma with indium 111, by incubating cells first with 2-mercaptopyridine N-oxide (Merc) and then with ionic or weakly chelated 111In citrate [24].
• The effect of coal tar distillate, cadmium sulfide, ichthyol sodium and omadine MDS on the epidermis of the guinea pig [25].

Gene context of SQ 2113

• This study shows that the drug 2-mercaptopyridine-N-oxide (MPNO) inhibits NADH-fumarate reductase purified from T. cruzi (ID50 = 35 microM) [26].

Analytical, diagnostic and therapeutic context of SQ 2113

• Fractionation of cells after treatment with Zn pyrithione showed that increased binding of PDBu occurred in the particulate fraction of cells and this was accompanied by loss of phorbol ester receptors from the cytosol [27].
• High-performance capillary electrophoresis determination of pyrithione in antidandruff preparations and shampoos [28].
• At the same time, their toxicity towards the organisms used in the toxicity bioassays (B. amphitrite nauplii, microalga Tetraselmis suecica and larvae of Mytilus galloprovincialis) was almost negligible in comparison to commercially available and currently used booster biocides based on copper and zinc complexes with pyrithione [29].

References