Protective effects of Lam. extract against learning and memory dysfunction induced by streptozotocin and amyloid β model.

Alzheimer's disease (AD) is associated with hyperglycaemia and amyloid beta (Aβ) accumulation. In the present study, we investigated whether an aqueous extract of Lam. (CCWE) improved cognitive disorder in a hyperglycaemic and cognitive-impaired mouse model. Hyperglycaemia was induced by streptozotocin (STZ, 50 mg/kg) and a single intracerebroventricular injection of Aβ (25 nM) was performed. The Aβ-injected hyperglycaemic mice were then administered CCWE (100 or 200 mg/kg/day) for 14-d. The protective effects of the CCWE were evaluated by behavioural tests and western blot analysis. The bioactive compounds in CCWE were isolated by UPLC-QTOF/MS analysis. The administration of CCWE improved the learning and memory function in STZ/Aβ-injected mice. Moreover, CCWE positively regulated the amyloidogenic pathway-related proteins and insulin signalling-related proteins. The bioactive components in CCWE were also identified. These findings suggest the possibility of CCWE as a potential candidate for the dual-targeting treatment of hyperglycaemia and AD.