Memory‐Enhancing Effects of the Crude Extract of Polygala tenuifolia on Aged Mice

Abstract

Learning and memory disorders arise from distinct age-associated processes, and aging animals are often used as a model of memory impairment. The root of Polygala tenuifolia has been commonly used in some Asian countries as memory enhancer and its memory improvement has been reported in various animal models. However, there is less research to verify its effect on memory functions in aged animals. Herein, the memory-enhancing effects of the crude extract of Polygala tenuifolia (EPT) on normal aged mice were assessed by Morris water maze (MWM) and step-down passive avoidance tests. In MWM tests, the impaired spatial memory of the aged mice was partly reversed by EPT (100 and 200 mg/kg; P < 0.05) as compared with the aged control mice. In step-down tests, the nonspatial memory of the aged mice was improved by EPT (100 and 200 mg/kg; P < 0.05). Additionally, EPT could increase superoxide dismutase (SOD) and catalase (CAT) activities, inhibit monoamine oxidase (MAO) and acetyl cholinesterase (AChE) activities, and decrease the levels of malondialdehyde (MDA) in the brain tissue of the aged mice. The results showed that EPT improved memory functions of the aged mice probably via its antioxidant properties and via decreasing the activities of MAO and AChE.

Cognitive-enhancing effects of hydrolysate of polygalasaponin in SAMP8 mice

“…("Yuanzhi" in Chinese) is a well-known traditional Chinese medicine (TCM) herb, which was first documented in Shen Nong Ben Cao Jing, and its dried root has for a long time been traditionally used to treat memory loss in Asian countries (Howes and Houghton, 2003;Kwon et al, 2004;Adams et al, 2007). Recent pharmacological studies have shown that P. tenuifolia could improve memory impairment caused by scopolamine, stress, glutamate, and Aβ, and promote neuronal proliferation in normal brains (Chung et al, 2002;Lin et al, 2012;Li et al, 2014). Polygalasaponins, such as polygalasaponin B, F, G, and XXXII, are the main components responsible for the action of P. tenuifolia and have been shown to improve cognitive impairment in AD effectively (Ikeya et al, 2004;Xu et al, 2009;Wu et al, 2014).…”

The herbal extract KCHO-1 exerts a neuroprotective effect by ameliorating oxidative stress via heme oxygenase-1 upregulation

“…KCHO-1 is a novel mixture comprised of 30% ethanol (EtOH) extracts obtained from nine natural products: Curcuma longa, Salvia miltiorrhiza, Gastrodia elata, Chaenomeles sinensis, Polygala tenuifolia, Paeonia japonica, Glycyrrhiza uralensis, Atractylodes japonica and processed Aconitum carmichaeli. These natural products are well known as traditional medicinal herbs, which are used as alternative therapies in Korea and China, and recent studies have reported the beneficial effects of these herbs (19)(20)(21)(22)(23)(24)(25). In our previous study, it was suggested that KCHO-1 exerted anti-inflammatory effects in BV2 microglia (26).…”

Co-treatment With the Herbal Medicine SIP3 and Donepezil Improves Memory and Depression in the Mouse Model of Alzheimer’s Disease

“…P. tenuifolia has been used as a cure for both insomnia and amnesia [18]. More recently, it has been prescribed for memory dysfunction and various brain in ammatory diseases [19].…”