Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disorder in which the neuromuscular junction progressively degenerates, leading to movement difficulties, paralysis, and eventually death. Often, the translation of preclinical findings to bedside terminates prematurely as the evaluation of potential therapeutic compounds focuses on a single study or a single animal model. To circumscribe these issues, we screened 3,765 novel small molecule derivatives of Pimozide, a recently identified repurposed neuroleptic for ALS, in Caenorhabditis elegans. TRVA242 was identified as the most potent compound as it significantly improved efficiency in rescuing locomotor, motorneuron, and neuromuscular junction synaptic deficits in a C. elegans TDP-43 model.
Age-synchronized young adult mTDP-43 transgenic worms were distributed in 96-well plate in M9 buffer (20μl per well, approximately 60 worms per well), containing DMSO or test compounds. The swimming activity of the nematodes was measured by a WMicrotracker machine. Experiments were done in triplicate. All positively acting compounds were retested. The experiments were conducted at 20°C. Significance was determined using a two-way ANOVA with multiple comparison post hoc analysis (GraphPad Prism).
Figure 1A shows an initial screening of compounds in worms. Specifically, we conducted a high-throughput screen of 3,768 compounds using transgenic C. elegans strains expressing mutant human TDP-43 (TARDBPA315T, referred to herein as mTDP-43). These worms show age-dependent motility defects leading to paralysis phenotypes in a matter of hours when grown in liquid culture. We initially identified 11 compounds that improved motility in mTDP-43 worms when tested for 6 h at a concentration of 20 μM. TRVA242 in the C. elegans model showed a potent rescue of the impaired swimming activity of mTDP-43 transgenic.
Neurotherapeutics . 2019 Oct;16(4):1149-1166. doi: 10.1007/s13311-019-00765-w.
Bose P, Tremblay E, Maois C, Narasimhan V, Armstrong GAB, Liao M, Parker JA, Robitaille R, Wen XY, Barden C, Drapeau P.