Parasitic nematodes cause a wide range of diseases in animals, including humans. However, the efficacy of existing anthelmintic drugs, commonly used to treat these infections, is waning due to the increasing prevalence of drug resistance in nematode populations. This growing challenge underscores the urgent need to discover and develop novel nematocidal drugs that target new molecular pathways. In the present study, 13 novel derivatives of benzhydroxamic acid (OMKs) were designed and synthesized. Their anthelmintic activity was tested in the parasitic nematode Haemonchus contortus (barber's pole worm) and the free-living nematode Caenorhabditis elegans and potential toxicity assessed in mammalian models. Compound OMK211 showed the most promising results. It decreased viability and motility of larval and adult stages of both nematode species and of both drug-sensitive and drug-resistant strains of H. contortus at micromolar concentrations with the highest efficacy in H. contortus adult males (IC50 ∼ 1 μM). Moreover, OMK211 was not toxic in mammalians cells in vitro and in mice in vivo. Consequently, thermal proteome profiling analysis was used to infer the putative molecular target of OMK211 in H. contortus. The results revealed C2-domain containing protein A0A6F7Q0A8, encoded by gene HCON_00184,900, as an interacting partner of OMK211. Using advanced structural prediction and docking tools, this protein is considered an interesting putative molecular target of new nematocidal drugs as its orthologs are present in several nematodes but not in mammals. In conclusion, novel derivatives of benzhydroxamic acid represent a promising new class of potential anthelmintics, which deserve further testing.

• Klíčová slova
• Drug development, Drug resistance, Nematodes, New anthelmintics,
• Publikační typ
• časopisecké články MeSH

In all organisms, the biotransformation of xenobiotics to less toxic and more hydrophilic compounds represents an effective defense strategy. In pathogens, the biotransformation of drugs (used for their elimination from the host) may provide undesirable protective effects that could potentially compromise the drug's efficacy. Accordingly, increased drug deactivation via accelerated biotransformation is now considered as one of the mechanisms of drug resistance. The present study summarizes the current knowledge regarding the biotransformation of anthelmintics, specifically drugs used to treat mainly nematodes, a group of parasites that are a significant health concern for humans and animals. The main biotransformation enzymes are introduced and their roles in anthelmintics metabolism in nematodes are discussed with a particular focus on their potential participation in drug resistance. Similarly, the inducibility of biotransformation enzymes with sublethal doses of anthelmintics is presented in view of its potential contribution to drug resistance development. In the conclusion, the main tasks awaiting scientists in this area are outlined.

• MeSH
• anthelmintika * farmakologie   metabolismus   farmakokinetika   MeSH
• biotransformace MeSH
• hlístice * účinky léků   metabolismus   enzymologie   MeSH
• léková rezistence * MeSH
• lidé MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• anthelmintika * MeSH

Aldo-keto reductases (AKRs), a superfamily of NADP(H)-dependent oxidoreductases, catalyze the oxidoreduction of a wide variety of eobiotic and xenobiotic aldehydes and ketones. In mammals, AKRs play essential roles in hormone and xenobiotic metabolism, oxidative stress, and drug resistance, but little is known about these enzymes in the parasitic nematode Haemonchus contortus. In the present study, 22 AKR genes existing in the H. contortus genome were investigated and a phylogenetic analysis with comparison to AKRs in Caenorhabditis elegans, sheep and humans was conducted. The constitutive transcription levels of all AKRs were measured in eggs, larvae, and adults of H. contortus, and their expression was compared in a drug-sensitive strain (ISE) and a benzimidazole-resistant strain (IRE) previously derived from the sensitive strain by imposing benzimidazole selection pressure. In addition, the inducibility of AKRs by exposure of H. contortus adults to benzimidazole anthelmintic flubendazole in vitro was tested. Phylogenetic analysis demonstrated that the majority of AKR genes in H. contortus lack orthologues in the sheep genome, which is a favorable finding for considering AKRs as potential drug targets. Large differences in the expression levels of individual AKRs were observed, with AKR1, AKR3, AKR8, and AKR10 being the most highly expressed at most developmental stages. Significant changes in the expression of AKRs during the life cycle and pronounced sex differences were found. Comparing the IRE and ISE strains, three AKRs were upregulated, and seven AKRs were downregulated in adults. In addition, the expression of three AKRs was induced by flubendazole exposure in adults of the ISE strain. Based on these results, AKR1, AKR2, AKR3, AKR5, AKR10 and AKR19 in particular merit further investigation and functional characterization with respect to their potential involvement in drug biotransformation and anthelmintic resistance in H. contortus.

• Klíčová slova
• AKR, Drug-resistance, Drug-susceptibility, Expression profile, Haemonchus contortus, Phylogenetic analysis,
• MeSH
• aldehydreduktasa genetika   metabolismus   MeSH
• aldo-keto reduktasy * genetika   metabolismus   MeSH
• anthelmintika farmakologie   MeSH
• benzimidazoly farmakologie   MeSH
• Caenorhabditis elegans genetika   účinky léků   enzymologie   MeSH
• fylogeneze * MeSH
• Haemonchus * genetika   účinky léků   enzymologie   MeSH
• léková rezistence genetika   MeSH
• lidé MeSH
• mebendazol * farmakologie   analogy a deriváty   MeSH
• ovce MeSH
• transkriptom MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• aldehydreduktasa MeSH
• aldo-keto reduktasy * MeSH
• anthelmintika MeSH
• benzimidazoly MeSH
• flubendazole MeSH Prohlížeč
• mebendazol * MeSH

Carbonyl-reducing enzymes (CREs) catalyse the reduction of carbonyl groups in many eobiotic and xenobiotic compounds in all organisms, including helminths. Previous studies have shown the important roles of CREs in the deactivation of several anthelmintic drugs (e.g., flubendazole and mebendazole) in adults infected with the parasitic nematode Haemonchus contortus, in which the activity of a CRE is increased in drug-resistant strains. The aim of the present study was to compare the abilities of nematodes of both a drug-susceptible strain (ISE) and a drug-resistant strain (IRE) to reduce the carbonyl group of flubendazole (FLU) in different developmental stages (eggs, L1/2 larvae, L3 larvae, and adults). In addition, the effects of selected CRE inhibitors (e.g., glycyrrhetinic acid, naringenin, silybin, luteolin, glyceraldehyde, and menadione) on the reduction of FLU were evaluated in vitro and ex vivo in H. contortus adults. The results showed that FLU was reduced by H. contortus in all developmental stages, with adult IRE females being the most metabolically active. Larvae (L1/2 and L3) and adult females of the IRE strain reduced FLU more effectively than those of the ISE strain. Data from the in vitro inhibition study (performed with cytosolic-like fractions of H. contortus adult homogenate) revealed that glycyrrhetinic acid, naringenin, mebendazole and menadione are effective inhibitors of FLU reduction. Ex vivo study data showed that menadione inhibited FLU reduction and also decreased the viability of H. contortus adults to a similar extent. Naringenin and mebendazole were not toxic at the concentrations tested, but they did not inhibit the reduction of FLU in adult worms ex vivo.

• Klíčová slova
• Anthelmintics, Strongyloides, drug biotransformation, helminths, inhibitors,
• MeSH
• anthelmintika * farmakologie   terapeutické užití   MeSH
• Haemonchus * MeSH
• kyselina glycyrhetinová * farmakologie   MeSH
• larva MeSH
• mebendazol farmakologie   terapeutické užití   MeSH
• vitamin K 3 farmakologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• anthelmintika * MeSH
• flubendazole MeSH Prohlížeč
• kyselina glycyrhetinová * MeSH
• mebendazol MeSH
• vitamin K 3 MeSH