Discovery of a Potent Botulinum Neurotoxin A Inhibitor ZM299 with Effective Protections in Botulism Mice

Abstract

Comprehensive Summary Botulinum neurotoxins serotype A (BoNT/A) is the deadliest toxins known to humans and the "Category A" agent for bioterrorism. Over the past 20 years, significant efforts have been put forth to develop effective inhibitors of BoNT/A. Unfortunately, few identified inhibitors possess noteworthy efficacy against BoNT/A in vivo. Here, we performed a high‐throughput virtual screening based on the structure‐based docking simulations and found a novel potent scaffold 2‐thionicotinate that inhibits the BoNT/A light chain (LC). We then synthesized and optimized a novel series of 2‐thionicotinate derivatives and comprehensively evaluated their activity against BoNT/A in vitro and in vivo. An optimized compound ZM299 effectively exhibits anti‐BoNT/A activity in primary neurons and displayed remarkably therapeutic efficacy against BoNT/A in vivo, which could raise the survival rate of intoxicated mice to 100% (12/12) after lethal doses of BoNT/A exposures. These findings demonstrate that 2‐thionicotinates is a promising scaffold for producing more effective anti‐BoNT/A analogs, and compound ZM299 is worthy of further preclinical evaluation as a drug candidate for the treatment of botulism.

Discovery of Novel 3,11‐Bispeptide Ester Arenobufagin Derivatives with Potential in Vivo Antitumor Activity and Reduced Cardiotoxicity

“…hERG‐CHO cells were cultured in T175 flasks to maximum 70–80 % confluence at 37 °C 5 % CO 2 incubator [21] . Then culture media was removed (F‐12 medium supplemented with 10 % fetal bovine serum, 100 μg/mL G418 and 100 μg/mL Hygromycin B) and washed with 7 mL PBS.…”

“…The absorbance (OD) was read on a WellscanMK-2 microplate reader incubator. [21] Then culture media was removed (F-12 medium supplemented with 10 % fetal bovine serum, 100 μg/mL G418 and 100 μg/mL Hygromycin B) and washed with 7 mL PBS. Followed by dissociation with 3 mL Detachin reagent in 37 °C incubator for ~3 min, and replaced with 7 mL serum-free media to gently resuspend cells using pipet up and down several times.…”