Synergistic effect of Korean red ginseng and Pueraria montana var. lobata against trimethyltin-induced cognitive impairment

Abstract

Many edible plant extracts exhibit biological activities. For example, the ethanol extract of Pueraria montana var. lobata (P. montana) inhibits acetylcholinesterase (AChE), and red ginseng is well known for promoting health. In this study the authors investigated the synergistic effect of P. montana and red ginseng extracts on AChE activity in vitro and in mouse brain tissues and trimethyltin (TMT)-induced cognitive impairment in a mouse model of TMT-induced neurodegeneration. A diet containing a mixture of P. montana and red ginseng extracts reversed learning and memory impairments in Y-maze and passive avoidance behavioral tests. In addition, the mixture inhibited AChE activity and lipid peroxidation synergistically.

Keywords: Alzheimer’s disease; Learning; Memory; Pueraria montana var. lobata; Red ginseng.

Fig. 1

Acetylcholinesterase (AChE) inhibition by Korean red ginseng (KRG) and Pueraria montana var. lobata (PM) extracts. The sample groups were treated with various mixtures of KRG and PM extracts (100:0, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80, 10:90, and 0:100 [w/w]). The concentration of all samples was 1 mg/mL, and the concentration of tacrine was 300 nM. Each value represents the mean ± SD (n = 4), p < 0.05. Different superscript symbols (*, #, ‡, and §) represent statistical differences between groups

Fig. 2

The effect of Korean red ginseng (KRG) and Pueraria montana var. lobata (PM) extracts on trimethyltin (TMT)-induced memory impairment in mice as measured by the Y-maze test. Spontaneous alternation behavior was measured over 8 min. The control group was injected with a sodium chloride solution. The TMT group was injected with a sodium chloride solution containing TMT. Sample groups were injected with TMT solution after pretreatment with KRG extract (800 mg/kg of body weight per day), PM extract (800 mg/kg of body weight per day), or KRG + PM extract (800 mg/kg of body weight per day). Each value represents the mean ± SD (n = 8), p < 0.05. Different superscript symbols (*, #, and §) represent statistical differences between groups

Fig. 3

The effect of KRG and PM extracts on TMT-induced memory impairment in mice as assessed by the passive avoidance test. Step-through latency was measured over 5 min. The control group was injected with a sodium chloride solution. The TMT group was injected with a sodium chloride solution containing TMT. Sample groups were injected with TMT solution after pretreatment with KRG extract (800 mg/kg of body weight per day), PM extract (800 mg/kg of body weight per day), or KRG + PM extract (800 mg/kg of body weight per day). Each value represents the mean ± SD (n = 8), p < 0.05. Different superscript symbols (*, #, and §) represent statistical differences between groups

Fig. 4

Effect of KRG and PM extracts on AChE activity and ACh contents in the mouse brain. The control group was injected with a sodium chloride solution. The TMT group was injected with a sodium chloride solution containing TMT. Sample groups were injected with TMT solution after pretreatment with KRG extract (800 mg/kg of body weight per day), PM extract (800 mg/kg of body weight per day), or KRG + PM extract (800 mg/kg of body weight per day). Each value represents the mean ± SD (n = 8), p < 0.05. Different superscript symbols (*, #, ‡, and §) represent statistical differences between groups

Fig. 5

Effect of KRG and PM extracts on lipid peroxidation in the mouse brain. The control group was injected with a sodium chloride solution. The TMT group was injected with a sodium chloride solution containing TMT. Sample groups were injected with TMT solution after pretreatment with KRG extract (800 mg/kg of body weight per day), PM extract (800 mg/kg of body weight per day), or KRG + PM extract (800 mg/kg of body weight per day). Each value represents the mean ± SD (n = 8), p < 0.05. Different superscript symbols (*, #, and §) represent statistical differences between groups

Fig. 6

Effect of KRG and PM extracts on catalase activity in the mouse brain. The control group was injected with a sodium chloride solution. The TMT group was injected with a sodium chloride solution containing TMT. Sample groups were injected with TMT solution after pretreatment with KRG extract (800 mg/kg of body weight per day), PM extract (800 mg/kg of body weight per day), or KRG + PM extract (800 mg/kg of body weight per day). Each value represents the mean ± SD (n = 8), p < 0.05. Different superscript symbols (*, #, and §) represent statistical differences between groups