Fig. 1

Behavioural performance of APP/PS1 and wild-type (wt) mice after oral treatment with S14. a Protocol A: treatment schedule for memory testing. Behavioural tests (BT) were carried out on days 28–35. S14 or vehicle (0.5% w/v Na-CMC and 0.1% v/v Tween 80 in water suspension) were orally administered once per day for 5 weeks until the end of the tests (day 35) when the animals were sacrificed (SAC). Protocol B: treatment schedule for neurogenesis testing. 5-Bromo-2’-deoxyuridine (BrdU) or saline was injected intraperitoneally (i.p.) on days 7–14. S14 or vehicle was orally administered once per day for 5 weeks until the end of the treatment (day 35) when the animals were sacrificed (SAC). b In the novel-object recognition test, APP/PS1 mice showed a significant decline in performance. In APP/PS1 mice orally treated with S14 for 5 weeks, the ratio exploring the novel object was enhanced. Data are expressed as mean ± SEM; n = 9–13 mice/group; *p < 0.05. c APP/PS1 mice exhibited impaired spatial memory in the Morris water maze test. d Latency to reach the platform on the last day of training was higher in APP/PS1 mice. S14 treatment restored the spatial memory in APP/PS1 mice since latency to reach the platform was similar to wild-type mice. Data are expressed as mean ± SEM; n = 9–13 mice/group; *p < 0.05. Statistical significance was assessed by two-way ANOVA followed by Fisher’s post-hoc test for multiple comparisons. Veh vehicle