Emodepside

Intestinal protozoa infections present a major public health challenge, particularly in areas with poor sanitation and limited access to clean water. Effective diagnostic methods are critical, yet traditional microscopy, though widely used for its simplicity, lacks the sensitivity and specificity of modern techniques like real-time Polymerase Chain Reaction (qPCR), making the latter a more effective tool for monitoring and assessing the burden of intestinal protozoa diseases. In this study, we implemented two duplex qPCR assays to detect Entamoeba dispar + Entamoeba histolytica and Cryptosporidium spp. + Chilomastix mesnili, along with singleplex assays for Giardia duodenalis and Blastocystis spp., using a 10 µL reaction volume. This marks the first molecular detection of Chilomastix mesnili by qPCR, enhancing diagnostic precision. Using these, we analyzed stool samples from 70 patients on Pemba Island, Tanzania, before and 54 samples after treatment with 20, 25, or 30 mg of emodepside or placebo, aiming to assess protozoa prevalence for this region and emodepside’s potential antiprotozoal effects. Our qPCR reliably detected protozoa in 74.4% of samples, with Entamoeba histolytica and Entamoeba dispar in 31.4% of cases. Notably, one-third of these infections were caused by Entamoeba histolytica. No significant reduction in protozoa was observed after emodepside treatment compared to placebo. The study highlights the utility of qPCR in providing species-level differentiation and improving the speed and cost-effectiveness of testing. The high prevalence of protozoa in this region underscores the need for continued monitoring and control efforts, though emodepside was not effective against protozoa infections.

This study focuses on the systematic exploration of the emodepside conformations bound to monovalent K+ ion using quantum mechanical density functional theory (DFT) calculations at the M06‐2X/6‐31+G(d,p) level of theory. Nine conformers of emodepside and their complexes with K+ ion were characterized as stationary points on the potential energy surface. The conformational isomers were examined for their 3D structures, bonding, energetics, and interactions with the cation. A cavitand‐like structure (CC) is identified to be the energetically most stable arrangement. To arrive at a better understanding of the K+ ion binding, calculations were initially performed on complexes formed by the K+ and Na+ ions with model ligands (methyl ester and N,N‐dimethyl acetamide). Both the natural bond orbital (NBO) method and the block‐localized wavefunction (BLW) energy decomposition approach was employed to assess the bonding and energetic contributions stabilizing the ion‐bound model complexes. Finally, the solvent effect was evaluated through complete geometry optimizations and energy minimizations for the model ion‐ligand complexes and the emodepside‐K+ bound complexes using an implicit solvent model mimicking water and DMSO.