Fig. 9.

Determining compound bioaccumulation in TDP-43(A315T) worms model worms using ¹H NMR. Overlay of spectra from lysates of chronically treated, age-synchronised day 1 adult TDP-43 expressing worms are shown, emphasising regions with compound-derived peaks of interest. (A) Succinimide (2.82–2.74 ppm) and (B) ethosuximide-derived peaks (1.30–1.28 ppm) were readily distinguishable in samples treated with an 8 mM external concentration of both compounds (red arrows). Peaks common to compound-treated and non-treated lysates arising from endogenous C. elegans metabolites are also shown alongside compound-derived peaks for comparison. Data shown are from nine ¹H spectra from three treatment conditions with three biological replicates each. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

(C,D) The singlet peak with the highest intensity from MPS (red boxed region) was indistinguishable from endogenous metabolites in samples treated with either the optimal neuroprotective concentration of 0.05 mM (C) or the highest tolerable concentration of 2 mM (D). Due to the undetectability of the singlet peak, the presence of other compound-derived multiplet peaks in the aromatic (E) or –CH₂ (F) region were analysed from spectra derived from treatment with both low and high concentrations. To facilitate peak identification from these multiplets, the reference spectrum of the pure compound was overlaid with those from treated worm lysates; reference peaks as shown in yellow and indicated with black arrows. These peaks were also not detectable from samples. Data shown is from nine ¹H spectra from three treatment conditions with three biological replicates each.