Decoquinate

Decoquinate is a coccidiostat.

Straightforward conversion of decoquinate into inexpensive tractable new derivatives with significant antimalarial activities.[Pubmed:27210430]

Bioorg Med Chem Lett. 2016 Jul 1;26(13):3006-3009.

As part of a programme aimed at identifying rational new triple drug combinations for treatment of malaria, tuberculosis and toxoplasmosis, we have selected quinolones as one component, given that selected examples exhibit exceptionally good activities against the causative pathogens of the foregoing diseases. The quinolone Decoquinate (DQ), an old and inexpensive coccidiostat, displays anti-malarial activity in vitro against Plasmodium falciparum (Pf). However, because of its exceedingly poor solubility in water or organic solvents, development of DQ as a drug is problematical. We have therefore converted DQ in straightforward fashion into tractable new derivatives that display good activities in vitro against chloroquine-sensitive NF54 and multidrug-resistant K1 and W2 Pf, and relatively low toxicities against human fibroblast cells. The most active compound, the N-acetyl derivative 30, is 5-fold more active than DQ against NF54 and K1 and equipotent with DQ against W2. It possesses an activity profile against all strains comparable with that of the artemisinin derivative artesunate. Overall, this compound and the other accessible and active derivatives serve as an attractive template for development of new and economic lead quinolones.

Nanoparticle formulations of decoquinate increase antimalarial efficacy against liver stage Plasmodium infections in mice.[Pubmed:23891618]

Nanomedicine. 2014 Jan;10(1):57-65.

UNLABELLED: Decoquinate has potent activity against both Plasmodium hepatic development and red cell replication when tested in vitro. Decoquinate, however, is practically insoluble in water. To achieve its maximal in vivo efficacy, we generated nanoparticle formulations of Decoquinate with a mean particle size less than 400 nm. Three separate preparations at doses of Decoquinate 0.5-5 mg/kg were examined in mice infected with Plasmodium berghei. Oral administration of nanoparticle Decoquinate at a dose of 1.25 mg/kg effectively inhibited the liver-stage parasite growth and provided complete causal prophylactic protection. This efficacy is 15 fold greater than that observed for microparticle Decoquinate, which requires minimal dose of 20 mg/kg for the same inhibitory effect. Further in vitro studies utilizing dose-response assays revealed that Decoquinate nanoformulation was substantially more potent than Decoquinate microsuspension in killing both liver and blood stage malarial parasites, proving its potential for therapeutic development. FROM THE CLINICAL EDITOR: In this study, a nanoparticle formulation of Decoquinate is shown to have superior bioavailability and efficacy in a mouse model of malaria, paving the way to the development of novel, potentially less toxic and more effective therapeutics to combat a disease that still has an enormous impact on a global scale despite the available partially effective therapies.

Deposition and depletion of decoquinate in eggs after administration of cross-contaminated feed.[Pubmed:25952987]

Food Addit Contam Part A Chem Anal Control Expo Risk Assess. 2015;32(7):1124-8.

Decoquinate, a chemical coccidiostat used as a feed additive, can occur in eggs due to cross-contamination of feedstuffs for laying hens. An experiment was designed to assess the transfer of Decoquinate to hen eggs and its distribution between egg yolk and egg white. Hens were given the feed containing Decoquinate at a cross-contamination level (0.34 mg kg(-1)) and collected eggs were analysed using an LC-MS/MS method. The plateau level was reached on the eighth day of the experiment and averaged 8.91 microg kg(-1), which is far below the maximum level established at 20 microg kg(-1) for whole eggs. Decoquinate was deposited mostly in egg yolks (26.2 microg kg(-1)) and did not deplete completely during 14 days of administration of Decoquinate-free feed. The results confirmed that administration of cross-contaminated feed is associated with very low risk of non-compliant residue levels of Decoquinate in eggs.

Efficacy of decoquinate against Sarcocystis neurona in cell cultures.[Pubmed:23523012]

Vet Parasitol. 2013 Sep 1;196(1-2):21-3.

Decoquinate is a quinolone anticoccidial approved for use in the prevention of intestinal coccidiosis in farm animals. This compound has good activity against Toxoplasma gondii and Neospora caninum in cell cultures. The drug acts on the parasites' mitochondria. The activity of Decoquinate against developing merozoites of 2 isolates of Sarcocystis neurona was examined in cell culture. Merozoite production at 10 days was completely inhibited when Decoquinate was used at 20 or 240 nM. The IC50 of Decoquinate was 0.5 +/- 0.09nM for the Sn6 isolate of S. neurona from a horse and 1.1 +/- 0.6 nM for the SnOP15 isolate of S. neurona from an opossum. Levamisole was toxic at 5 mug/ml and no synergism was observed when Decoquinate was combined with levamisole and tested against the Sn3YFP isolate of S. neurona. Decoquinate was cidal for developing schizonts of S. neurona at 240 nM.