Background and Objectives: Nelumbo nucifera
(lotus) is a key plant in Thai traditional medicine that
has anti-diabetic and anti-oxidant activities, and
inhibits acetylcholinesterase enzyme. It is widely
consumed as functional food. This study investigated
the effect of N. nucifera stamen extract (NNSE) on
memory deficit in amyloid beta (Aβ)-induced rat.
Methods: Forty adult male Sprague Dawley rats were
divided into 5 groups, each group consisting of 8 rats
as follows: Group 1, the normal control group. Group
2, the vehicle plus Aβ group (V+Aβ), received 0.5%
sodium carboxymethyl cellulose, orally and was
injected with amyloid-β via the lateral ventricles.
Group 3, the vitamin C plus Aβ group (Vit C+Aβ),
received vitamin C orally at 200 mg/kgBW., and was
injected with Aβ via the lateral ventricles. Group 4,
and 5, the NNSE plus Aβ groups (NNSE250+Aβ,
NNSE500+Aβ), received NNSE orally at doses of 250,
and 500 mg/kgBW, respectively, and were injected with Aβ via the lateral ventricles. All treatments were
performed for 33 consecutive days. At day 21, Aβ (1-
42) was injected via both sides of lateral ventricles.
Ten days after Aβ1-42 injection, the rats were tested
for locomotor activity and recognition memory by
using the open field and novel object recognition
tasks, respectively.
Results: The NNSE at dose of 500 mg/kg BW
significantly increase the velocity and moving distance
in locomotor activity in rats after induced with Aβ.
Moreover, NNSE at doses of 250 and 500 mg/kgBW
significantly improve short-term recognition in
cognitively impaired rats. These doses of NNSE also
tend to improve long-term recognition in memory
impaired rats.
Conclusions: NNSE improve memory impairments
induced by Aβ, especially short-term memory.
Furthermore, the high doses of NNSE stimulates muscle
function by increasing speed and movement
distance.