Pyridoxine (Pyr)-dependent epilepsy in aldh7a1−/− larvae. Pyridoxal 5′-phosphate (PLP) treatment promoted dose-dependent increase in survival of mutant larvae (A). Pyr treatment also led to prolonged life span of the null-mutants, with 100% survival until juvenile stage (5 and 10 mM daily) (B). In both cases, experiments were terminated at 40 days postfertilization (dpf) and consisted of n = 5 individuals per group except for untreated aldh7a1−/− (n = 12). Representative movement traces obtained from Zebralab software showing in red, high-speed, green, intermediate, and black, slow movements for mutants and their wild-type (WT) siblings, untreated and treated with Pyr 10 mM (C). Movement analysis using Zebralab showing duration (D) and distance traveled in high-speed movements (E). Blinded analysis of baseline (F) and light stimulus (G) video recordings classified the behavior in seizure scores as described previously. N = 16 aldh7a1−/− untreated, n = 8 aldh7a1−/− + Pyr 10 mM, n = 16 WT untreated, and n = 8 WT + Pyr 10 mM (D–G). Total event duration of the electrographic seizure-like bursts (H) and total number of such events (I) observed in a window of 5 min for n = 5 WT siblings, n = 5 untreated aldh7a1−/−, and n = 9 aldh7a1−/− treated with Pyr 10 mM. Examples of traces of treated mutants showing magnification of one burst are shown in “i” (J). Western blot probing with anti-c-Fos and anti-ALDH7A1 antibodies (K); each lane corresponds to protein extracts of a single larva. Asterisks indicate statistical significance (* P < 0.05, ** P < 0.01, and *** P < 0.001) based on ANOVA test with Tukey’s post hoc pairwise tests. Error bars represent ± SD. All experiments were performed comparing aldh7a1−/− and its WT siblings. Electrophysiology measurements were performed using four different batches of larvae.
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