Dataset Information

Peptidomimetic Vinyl Heterocyclic Inhibitors of Cruzain Effect Antitrypanosomal Activity.

ABSTRACT: Cruzain, an essential cysteine protease of the parasitic protozoan, Trypanosoma cruzi, is an important drug target for Chagas disease. We describe here a new series of reversible but time-dependent inhibitors of cruzain, composed of a dipeptide scaffold appended to vinyl heterocycles meant to provide replacements for the irreversible reactive "warheads" of vinyl sulfone inactivators of cruzain. Peptidomimetic vinyl heterocyclic inhibitors (PVHIs) containing Cbz-Phe-Phe/homoPhe scaffolds with vinyl-2-pyrimidine, vinyl-2-pyridine, and vinyl-2-(N-methyl)-pyridine groups conferred reversible, time-dependent inhibition of cruzain (Ki* = 0.1-0.4 ?M). These cruzain inhibitors exhibited moderate to excellent selectivity versus human cathepsins B, L, and S and showed no apparent toxicity to human cells but were effective in cell cultures of Trypanosoma brucei brucei (EC50 = 1-15 ?M) and eliminated T. cruzi in infected murine cardiomyoblasts (EC50 = 5-8 ?M). PVHIs represent a new class of cruzain inhibitors that could progress to viable candidate compounds to treat Chagas disease and human sleeping sickness.

SUBMITTER: Chenna BC

PROVIDER: S-EPMC7261474 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Peptidomimetic Vinyl Heterocyclic Inhibitors of Cruzain Effect Antitrypanosomal Activity.

Chenna Bala C BC Li Linfeng L Mellott Drake M DM Zhai Xiang X Siqueira-Neto Jair L JL Calvet Alvarez Claudia C Bernatchez Jean A JA Desormeaux Emily E Alvarez Hernandez Elizabeth E Gomez Jana J McKerrow James H JH Cruz-Reyes Jorge J Meek Thomas D TD

Journal of medicinal chemistry 20200317 6

Cruzain, an essential cysteine protease of the parasitic protozoan, <i>Trypanosoma cruzi</i>, is an important drug target for Chagas disease. We describe here a new series of reversible but time-dependent inhibitors of cruzain, composed of a dipeptide scaffold appended to vinyl heterocycles meant to provide replacements for the irreversible reactive "warheads" of vinyl sulfone inactivators of cruzain. Peptidomimetic vinyl heterocyclic inhibitors (PVHIs) containing Cbz-Phe-Phe/homoPhe scaffolds w ...[more]

PMID: 32125159

Similar Datasets

Project description:A multi-step cascade strategy using integrated ligand- and target-based virtual screening methods was developed to select a small number of compounds from the ZINC database to be evaluated for trypanocidal activity. Winnowing the database to 23 selected compounds, 12 non-covalent binding cruzain inhibitors with affinity values (K i) in the low micromolar range (3-60 µM) acting through a competitive inhibition mechanism were identified. This mechanism has been confirmed by determining the binding mode of the cruzain inhibitor Nequimed176 through X-ray crystallographic studies. Cruzain, a validated therapeutic target for new chemotherapy for Chagas disease, also shares high similarity with the mammalian homolog cathepsin L. Because increased activity of cathepsin L is related to invasive properties and has been linked to metastatic cancer cells, cruzain inhibitors from the same library were assayed against it. Affinity values were in a similar range (4-80 µM), yielding poor selectivity towards cruzain but raising the possibility of investigating such inhibitors for their effect on cell proliferation. In order to select the most promising enzyme inhibitors retaining trypanocidal activity for structure-activity relationship (SAR) studies, the most potent cruzain inhibitors were assayed against T. cruzi-infected cells. Two compounds were found to have trypanocidal activity. Using compound Nequimed42 as precursor, an SAR was established in which the 2-acetamidothiophene-3-carboxamide group was identified as essential for enzyme and parasite inhibition activities. The IC50 value for compound Nequimed42 acting against the trypomastigote form of the Tulahuen lacZ strain was found to be 10.6±0.1 µM, tenfold lower than that obtained for benznidazole, which was taken as positive control. In addition, by employing the strategy of molecular simplification, a smaller compound derived from Nequimed42 with a ligand efficiency (LE) of 0.33 kcal mol(-1) atom(-1) (compound Nequimed176) is highlighted as a novel non-peptidic, non-covalent cruzain inhibitor as a trypanocidal agent candidate for optimization.

Dataset Information

Peptidomimetic Vinyl Heterocyclic Inhibitors of Cruzain Effect Antitrypanosomal Activity.

Publications

Peptidomimetic Vinyl Heterocyclic Inhibitors of Cruzain Effect Antitrypanosomal Activity.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure