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.

• Keywords
• Drug development, Drug resistance, Nematodes, New anthelmintics,
• MeSH
• Anthelmintics * pharmacology   chemistry   MeSH
• Antinematodal Agents * pharmacology   chemistry   chemical synthesis   MeSH
• Caenorhabditis elegans * drug effects   MeSH
• Haemonchus * drug effects   MeSH
• Haemonchiasis drug therapy   parasitology   MeSH
• Hydroxamic Acids * pharmacology   chemistry   chemical synthesis   MeSH
• Larva drug effects   MeSH
• Mice MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anthelmintics * MeSH
• Antinematodal Agents * MeSH
• Hydroxamic Acids * MeSH

Most drugs used in the treatment of helminthiasis in humans and animals have lost their efficacy due to the development of drug-resistance in helminths. Moreover, since anthelmintics, like many pharmaceuticals, are now recognized as hazardous contaminants of the environment, returning to medicinal plants and their products represents an environmentally friendly way to treat helminthiasis. The goal of the present study was to test the anthelminthic activity of methanol extracts of eight selected European ferns from the genera Dryopteris, Athyrium and Blechnum against the nematode Haemonchus contortus, a widespread parasite of small ruminants. Eggs and adults of H. contortus drug-susceptible strain ISE and drug-resistant strain WR were isolated from experimentally infected sheep. The efficacy of fern extracts was assayed using egg hatch test and adults viability test based on ATP-level measurement. Among the ferns tested, only Dryopteris aemula extract (0.2 mg/mL) inhibited eggs hatching by 25% in comparison to control. Athyrium distentifolium, Dryopteris aemula and Dryopteris cambrensis were effective against H. contortus adults. In concentration 0.1 mg/mL, A. distentifolium, D. aemula, D. cambrensis significantly decreased the viability of females from ISE and WR strains to 36.2%, 51.9%, 32.9% and to 35.3%, 27.0%, 23.3%, respectively in comparison to untreated controls. None of the extracts exhibited toxicity in precise cut slices from ovine liver. Polyphenol's analysis identified quercetin, kaempferol, luteolin, 3-hydroxybenzoic acid, caffeic acid, coumaric acid and protocatechuic acid as the major components of these anthelmintically active ferns.

• Keywords
• ATP-assay, Athyrium, Dryopteris, Natural anthelmintics, medicinal plants, nematodes,
• MeSH
• Anthelmintics * pharmacology   therapeutic use   MeSH
• Haemonchus * MeSH
• Helminthiasis * MeSH
• Ferns * MeSH
• Larva MeSH
• Humans MeSH
• Sheep Diseases * drug therapy   parasitology   MeSH
• Sheep MeSH
• Plant Extracts pharmacology   MeSH
• Veterinary Drugs * pharmacology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anthelmintics * MeSH
• Plant Extracts MeSH
• Veterinary Drugs * MeSH

As a widely distributed parasitic nematode of ruminants, Haemonchus contortus has become resistant to most anthelmintic classes, there has been a major demand for new compounds against H. contortus and related nematodes. Recent phenotypic screening has revealed two compounds, designated as BLK127 and HBK4, that are active against H. contortus larvae. The present study was designed to assess the activity of these compounds against H. contortus eggs and adults, hepatotoxicity in rats and sheep, as well as biotransformation in H. contortus adults and the ovine liver. Both compounds exhibited no inhibitory effect on the hatching of eggs. The benzyloxy amide BLK127 significantly decreased the viability of adults in sensitive and resistant strains of H. contortus and showed no hepatotoxic effect, even at the highest concentration tested (100 µM). In contrast, HBK4 had no impact on the viability of H. contortus adults and exhibited significant hepatotoxicity. Based on these findings, HBK4 was excluded from further studies, while BLK127 seems to be a potential candidate for a new anthelmintic. Consequently, biotransformation of BLK127 was tested in H. contortus adults and the ovine liver. In H. contortus, several metabolites formed via hydroxylation, hydrolysis and glycosidation were identified, but the extent of biotransformation was low, and the total quantity of the metabolites formed did not differ significantly between the sensitive and resistant strains. In contrast, ovine liver cells metabolized BLK127 more extensively with a glycine conjugate of 4-(pentyloxy)benzoic acid as the main BLK127 metabolite.

• Keywords
• ATP, drug development, drug metabolism, drug resistance, nematodes, new anthelmintics,
• Publication type
• Journal Article MeSH

Haemonchus contortus is a parasitic nematode of ruminants which causes significant losses to many farmers worldwide. Since the drugs currently in use for the treatment of haemonchosis are losing their effectiveness due to the drug-resistance of this nematode, a new or repurposed drug is highly needed. As the antipsychotic drug sertraline (SRT) has been shown to be effective against the parasitic nematodes Trichuris muris, Ancylostoma caninum and Schistosoma mansoni, the aim of the present study was to evaluate the possible effect of SRT on H. contortus. The potential hepatotoxicity of SRT was tested in sheep, a common H. contortus host. In addition, the main metabolic pathways of SRT in H. contortus and the ovine liver were identified. While no effect of SRT on H. contortus egg hatching was observed, SRT was found to significantly decrease the viability of H. contortus adults in drug-sensitive and resistant strains, with its effect comparable to the commonly used anthelmintics levamisole and monepantel. Moreover, SRT in anthelmintically active concentrations showed no toxicity to the ovine liver. Biotransformation of SRT in H. contortus was weak, with most of the drug remaining unmetabolized. Production of the main metabolite hydroxy-SRT did not differ significantly between strains. Other minor metabolites such as SRT-O-glucoside, dihydroxy-SRT, and SRT-ketone were also identified in H. contorts adults. Compared to H. contortus, the ovine liver metabolized SRT more extensively, mainly via desmethylation and glucuronidation. In conclusion, the potency of SRT against H. contortus was proven, and it should be tested further toward possible repurposing.

• Keywords
• Drug repurposing, drug metabolism, drug resistance, hepatotoxicity, nematodes,
• MeSH
• Anthelmintics * pharmacology   toxicity   MeSH
• Biotransformation MeSH
• Haemonchus drug effects   MeSH
• Haemonchiasis * drug therapy   veterinary   MeSH
• Sheep Diseases * drug therapy   MeSH
• Sheep MeSH
• Sertraline * pharmacology   toxicity   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anthelmintics * MeSH
• Sertraline * MeSH

The selection of a suitable combination of reference genes (RGs) for data normalization is a crucial step for obtaining reliable and reproducible results from transcriptional response analysis using a reverse transcription-quantitative polymerase chain reaction. This is especially so if a three-dimensional multicellular model prepared from liver tissues originating from biologically diverse human individuals is used. The mRNA and miRNA RGs stability were studied in thirty-five human liver tissue samples and twelve precision-cut human liver slices (PCLS) treated for 24 h with dimethyl sulfoxide (controls) and PCLS treated with β-naphthoflavone (10 µM) or rifampicin (10 µM) as cytochrome P450 (CYP) inducers. Validation of RGs was performed by an expression analysis of CYP3A4 and CYP1A2 on rifampicin and β-naphthoflavone induction, respectively. Regarding mRNA, the best combination of RGs for the controls was YWHAZ and B2M, while YWHAZ and ACTB were selected for the liver samples and treated PCLS. Stability of all candidate miRNA RGs was comparable or better than that of generally used short non-coding RNA U6. The best combination for the control PCLS was miR-16-5p and miR-152-3p, in contrast to the miR-16-5b and miR-23b-3p selected for the treated PCLS. Our results showed that the candidate RGs were rather stable, especially for miRNA in human PCLS.

• Keywords
• RT-qPCR, human liver, mRNA, miRNA, precision-cut liver slices, reference gene,
• MeSH
• beta 2-Microglobulin genetics   metabolism   MeSH
• beta-Naphthoflavone pharmacology   MeSH
• Cytochrome P-450 CYP1A2 genetics   metabolism   MeSH
• Cytochrome P-450 CYP3A genetics   metabolism   MeSH
• Dimethyl Sulfoxide pharmacology   MeSH
• Adult MeSH
• Liver drug effects   metabolism   MeSH
• Real-Time Polymerase Chain Reaction standards   MeSH
• Middle Aged MeSH
• Humans MeSH
• RNA, Messenger genetics   metabolism   MeSH
• MicroRNAs genetics   metabolism   MeSH
• 14-3-3 Proteins genetics   metabolism   MeSH
• Reference Standards MeSH
• Rifampin pharmacology   MeSH
• Aged MeSH
• Gene Expression Profiling standards   MeSH
• Cytochrome P-450 Enzyme System pharmacology   MeSH
• Transcriptome MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• B2M protein, human MeSH Browser
• beta 2-Microglobulin MeSH
• beta-Naphthoflavone MeSH
• CYP1A2 protein, human MeSH Browser
• CYP3A4 protein, human MeSH Browser
• Cytochrome P-450 CYP1A2 MeSH
• Cytochrome P-450 CYP3A MeSH
• Dimethyl Sulfoxide MeSH
• RNA, Messenger MeSH
• MicroRNAs MeSH
• 14-3-3 Proteins MeSH
• Rifampin MeSH
• Cytochrome P-450 Enzyme System MeSH
• YWHAZ protein, human MeSH Browser

Sesquiterpenes, the main components of plant essential oils, are bioactive compounds with numerous health-beneficial activities. Sesquiterpenes can interact with concomitantly administered drugs due to the modulation of drug-metabolizing enzymes (DMEs). The aim of this study was to evaluate the modulatory effects of six sesquiterpenes (farnesol, cis-nerolidol, trans-nerolidol, α-humulene, β-caryophyllene, and caryophyllene oxide) on the expression of four phase I DMEs (cytochrome P450 3A4 and 2C, carbonyl reductase 1, and aldo-keto reductase 1C) at both the mRNA and protein levels. For this purpose, human precision-cut liver slices (PCLS) prepared from 10 patients and transfected HepG2 cells were used. Western blotting, quantitative real-time PCR and reporter gene assays were employed in the analyses. In the reporter gene assays, all sesquiterpenes significantly induced cytochrome P450 3A4 expression via pregnane X receptor interaction. However in PCLS, their effects on the expression of all the tested DMEs at the mRNA and protein levels were mild or none. High inter-individual variabilities in the basal levels as well as in modulatory efficacy of the tested sesquiterpenes were observed, indicating a high probability of marked differences in the effects of these compounds among the general population. Nevertheless, it seems unlikely that the studied sesquiterpenes would remarkably influence the bioavailability and efficacy of concomitantly administered drugs.

• Keywords
• cytochrome P450 3A4, gene reporter assay, mRNA expression, precision-cut liver slices, pregnane X receptor, protein expression, sesquiterpene,
• MeSH
• Aldo-Keto Reductases metabolism   MeSH
• Hep G2 Cells MeSH
• Cytochrome P-450 CYP3A metabolism   MeSH
• Farnesol pharmacology   MeSH
• Hepatocytes metabolism   MeSH
• Liver enzymology   MeSH
• Carbonyl Reductase (NADPH) metabolism   MeSH
• Middle Aged MeSH
• Humans MeSH
• RNA, Messenger metabolism   MeSH
• Metabolic Clearance Rate MeSH
• Monocyclic Sesquiterpenes pharmacology   MeSH
• Polycyclic Sesquiterpenes pharmacology   MeSH
• Pregnane X Receptor agonists   metabolism   MeSH
• Receptors, Aryl Hydrocarbon agonists   metabolism   MeSH
• Cytochrome P450 Family 2 metabolism   MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Sesquiterpenes pharmacology   MeSH
• Cytochrome P-450 Enzyme System metabolism   MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Aldo-Keto Reductases MeSH
• caryophyllene oxide MeSH Browser
• caryophyllene MeSH Browser
• Cytochrome P-450 CYP3A MeSH
• cytochrome P-450 CYP2C subfamily MeSH Browser
• Farnesol MeSH
• humulene MeSH Browser
• Carbonyl Reductase (NADPH) MeSH
• RNA, Messenger MeSH
• Monocyclic Sesquiterpenes MeSH
• nerolidol MeSH Browser
• Polycyclic Sesquiterpenes MeSH
• Pregnane X Receptor MeSH
• Receptors, Aryl Hydrocarbon MeSH
• Cytochrome P450 Family 2 MeSH
• Sesquiterpenes MeSH
• Cytochrome P-450 Enzyme System MeSH