Fig. 3: Treatment with lead ASO KT777 reduces KCNT1 levels and improves life expectancy and neurocognitive defects of Kcnt1 P905L(L/L) mice.
a,b, Measurement of levels of mouse Kcnt1 (a) or human KCNT1 (b) in the cortex of human KCNT1 (hKCNT1)-expressing mice, 10–11 days after injection with vehicle (untreated), control ASO and KT777. Asterisks denote significant changes from the ASO control (control ASO 4 100 μg versus KT777 500 μg, P = 0.0003, and control ASO 4 100 μg versus KT777 1,000 μg, P ≤ 0.0001, in a; control ASO 4 100 μg versus KT777 500 μg, P = 0.0077, and control ASO 4 100 μg versus KT777 1,000 μg, P = 0.0031, in b). Untreated n = 7; control ASO 100 µg n = 2; KT777 100 µg n = 3, 500 µg n = 4 and 1,000 µg n = 2. c,d, IT administration of KT777 in WT rats. Injection protocols are shown at the top with dosing days (red bars) and analysis points (blue arrows). Single administration of KT777 at 200 µg and 2,000 µg (c) elicits reduction of Kcnt1 levels in the rat frontal cortex at 14 days postinjection (untreated versus 200 μg P = 0.0184). KT777 was robustly detected in CSF 14 days after dose. n = 4 except for n = 3 for KT777 CSF concentration at 200 µg. Repeat dosing of KT777 at 800 µg (d) leads to a significant decrease of Kcnt1 in the rat frontal cortex at 115 days (untreated versus 800 μg, P < 0.0001). Untreated n = 6, 50 µg n = 6, 200 µg n = 5 and 800 µg n = 6. KT777 was detected in a dose-dependent manner in CSF. 50 µg n = 3, 200 µg n = 13 and 800 µg n = 12. e, Treatment with KT777ps improves life expectancy in Kcnt1 P905L(L/L) mice. P905L(L/L) mice were dosed with KT777ps at 100 µg once (1× KT777ps, n = 5) or twice (2× KT777ps, n = 11). Times of dosing were P31–35 for the first dose and P149–164 for the second dose. Four mice not recovering from the first administration surgery were excluded. Five mice that received a single dose of KT777ps died at 1 day, 75 days, 75 days, 86 days and 169 days postinjection, respectively. The survival curve of untreated mice was obtained from previous data17. f, Nest building scores of Kcnt1 P905L(L/L) mice improved after treatment with KT777ps (100 μg ICV, ‘Post’, n = 4) compared with the untreated condition (‘Pre’, n = 4). Symbols are 48-h values after the initiation of the nest-building experiment for each mouse. Four mice that survived until 2 weeks after administration of KT777ps were reassessed for nest building. The mean nest building score after treatment was significantly improved from the untreated condition (P < 0.01). Horizontal lines represent the mean for each group (n = 4). For panels a–d, data are presented as mean values ± s.e.m. *P < 0.05, **P < 0.01 and ***P < 0.001, comparing treatment groups from samples tested by control ASOs or untreated samples (one-way ANOVA with Dunnett’s multiple comparisons test). For panel f, data are presented as mean values. **P < 0.01, from the pretreatment baseline (two-tailed Mann–Whitney U test). tg, transgenic; conc., concentration; D, day.
