The identification of small molecule inhibitors with anthelmintic activities that target conserved proteins among ruminant gastrointestinal nematodes

Authors: JUNG, HYEIM - Washington University School Of Medicine; ZARLENGA, DANTE - Former ARS Employee; MARTIN, JOHN - Ghent University; GELDHOF, PETER - Washington University School Of Medicine; HALLSWORTH-PEPIN, KYMBERLIE - Washington University School Of Medicine; MITREVA, MAKEDONKA - Washington University School Of Medicine

Submitted to: mBio
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/22/2024
Publication Date: 2/15/2024
Citation: Jung, H., Zarlenga, D., Martin, J.C., Geldhof, P., Hallsworth-Pepin, K., Mitreva, M. 2024. The identification of small molecule inhibitors with anthelmintic activities that target conserved proteins among ruminant gastrointestinal nematodes. mBio. 15(3). Article e00095. https://doi.org/10.1128/mbio.00095-24.
DOI: https://doi.org/10.1128/mbio.00095-24

Interpretive Summary: Gastrointestinal nematode (GIN) infections in ruminants are caused by parasites that inhibit normal function in the digestive tract of cattle, sheep, and goats thereby causing morbidity and mortality. Coinfection and increasing drug resistance to current therapeutic agents will continue to worsen disease outcomes and impose significant production losses in domestic livestock producers worldwide. In combination with ongoing therapeutic efforts, advancing the discovery of new drugs with novel modes of action is critical for better controlling GIN infections. Herein we assembled and characterized the genomes of 3 GIN to facilitate a multi-genomics approach to identify novel, biologically conserved drug targets for 5 major GINs of veterinary importance. We used this information to demonstrate the potential of commercially available compounds as new anthelmintics. This information can be used by scientists and veterinary companies to develop new anthelmintics against the most common and devastating GINs of goats, sheep and cows worldwide.

Technical Abstract: Gastrointestinal nematode (GIN) infections are a major concern to the ruminant industry worldwide and result in significant production losses. Naturally occurring polyparasitism and increasing drug resistance that potentiate disease outcomes are observed among the most prevalent GINs of veterinary importance. To better understand parasite biology, evolution, and parasitism, we first assembled draft genomes of Cooperia oncophora, Trichostrongylus colubriformis, and Ostertagia ostertagi (clade Va), and compared these with genomes of closely related ruminant GINs (clade V). Genome-wide phylogenetic reconstruction showed a relationship among ruminant GINs in clade V structured by taxonomic classification. Based on orthogroup (OG) inference and functional enrichment analyses, we identified 220 clade Va-specific and Va-conserved (VaSC) OGs whose functions were significantly enriched in cell cycle and cellular senescence. Comparative transcriptomic analysis revealed a total of 61 OGs that were taxonomically and functionally conserved across all ruminant clade Va GINs examined, and that may function as drug targets for new broad-spectrum anthelmintics. Next, we performed a chemogenomic screening using the ChEMBL database and prioritized 11 commercially available compounds as potential anthelmintics predicted to target the conserved proteins in the ruminant clade Va GINs. In vitro phenotypic assays demonstrated that three kinase inhibitors (digitoxigenin, K-252A, and Staurosporine) exhibited broad-spectrum anthelmintic activities against ruminant GINs in clade Va by obstructing motility of exsheathed L3 (xL3) or molting of xL3 to L4. These results demonstrate novel applications for the new genomes in ruminant GINs, provide better insights into the life cycles of GINs, and afford a contemporary approach for discovering the next generation of anthelmintics.