In vitro and in vivo assessment on memory improvement of Lac Tien Thang

Memory impairment is a condition observed at all ages, particularly with a notably higher prevalence among the elderly, causing critical damages to both mental, physical states and daily activities. Lac Tien Thang (LTT; Vietnamese: Lạc Tiên Thang) was selected based on the convergence of traditional Vietnamese medical theory and modern pharmacological evidence in treating central nervous system disorders. Traditionally, it is used for sedative and cognition-enhancing effects, while modern studies show its flavonoid- and phenolic-rich components provide neuroprotective, antioxidant, anti-inflammatory and cognitive benefits. This study focused on investigating the memory-enhancing effects of the aqueous extract from LTT, which was evaluated in both in vitro and in vivo models to assess its inhibitory activity against acetylcholinesterase enzyme (AChE). The aqueous extract from LTT was analysed for a preliminary screening on its chemical compositions and total flavonoid quantification and inhibitory function of AChE enzyme in vitro using Ellman method as well as its memory improvement effects on Swiss albino mice following the novel object recognition test (NORT). The preliminary analysis on phytochemicals identified various components, which consisted of essential oils, triterpenoid, flavonoids, alkaloids, cardiac glycosides, polyphenols, organic acids, reducing agents and polyrunoic compounds. The total flavonoid content was 3.35 %, LTT successfully inhibited AChE activity, with an IC50 recorded at 88.95 µg/mL. The LTT extract at a dose of 2.61 g/kg presented an effective function in memory enhancing on Swiss albino mice induced memory impairment by 2.6 mg/kg of Trimethyltin chloride (TMT). Therefore, LTT extract can inhibit AchE activity and effectively improve memory in mice.