alpha-asarone and Memory-Disorders

Alzheimer's disease (AD) is a neurological ailment that causes memory loss and impairments and is linked to a drop-in acetylcholine level. Acetylcholinesterase (AChE) inhibitors are used for the management of AD. In our ongoing research to search for natural AChE inhibitors from medicinal plants, we found that the Acorus calamus possesses memory-enhancing properties. α-Asarone is the major compound isolated from the Acorus calamus and it has neuroprotective action in animal models, nonetheless, its anticholinesterase activity in different brain regions was not fully understood. The purpose of this research was to determine the anti-amnesic and anti-cholinesterase activities of α-asarone against scopolamine-induced memory impairments in rats.. The anti-cholinesterase activity of α-asarone was determined using Ellman's method in different brain areas, such as the cortex, hippocampus, and striatum. In addition, the anti-amnesic effect of α-asarone was also investigated using elevated plus-maze, passive avoidance, and active avoidance tests.. The effect of α-asarone on memory impairment against scopolamine-induced (1 mg/kg body weight) amnesia was evaluated. Administration of α-asarone (15 and 30 mg/kg body weight) for 14 days to rats significantly ameliorated the scopolamine-induced memory impairment as measured in the elevated plus-maze, passive avoidance, and avoidance active tests compared to the scopolamine-treated group. In this study, we also show that α-asarone treatment significantly (p<0.05) reduced brain acetylcholinesterase activity in the cortex, hippocampus, and striatum brain regions of amnesic rats.. These results confirmed that α-asarone has anti-amnesic and anti-cholinesterase potential which may be useful for the management of AD.

Topics: Acetylcholine; Acetylcholinesterase; Allylbenzene Derivatives; Alzheimer Disease; Amnesia; Animals; Anisoles; Avoidance Learning; Body Weight; Cholinesterase Inhibitors; Maze Learning; Memory Disorders; Rats; Scopolamine

Learning and memory impairment is a common symptom in the early stages of various types of dementia. It is likely to reduce the incidence of dementia with correct intervention. α-Asarone is the main bioactive substance isolated from Acorus tatarinowii Schott and has been proven to improve memory dysfunction; however, at present, the specific underlying mechanism is poorly understood. The aim of the present study was to investigate the effect of α-asarone on ethanol-impaired cognitive ability and explore the underlying mechanism in mice.. A mouse model of impaired learning and memory was created by ethanol (2.0 g/kg, i.g.). α-Asarone (7.5, 15 or 30 mg/kg, i.p.) was delivered 10 min prior to ethanol administration. The behavioral effect of α-asarone was evaluated using the novel object recognition test. Glutamate (Glu) and γ-aminobutyric acid (GABA) levels in the hippocampus were determined by ELISA, and the protein expression levels of hippocampal GluR2, NMDAR2B, SYNΙ, GLT-1 and CaMKⅡ were detected by western blotting.. Pretreatment with α-asarone significantly improved the behavioral performance, regulated the imbalance of Glu and GABA in the hippocampus and the abnormal expression of related proteins. A possible underlying mechanism is regulation of the calcium signaling cascade to correct functioning of related proteins, and thus, maintain the level of Glu.. Our results show that the improvement in learning and memory elicited by α-asarone may providing a possible novel candidate for the prevention of learning and memory impairment in the early stages of dementia.

Topics: Allylbenzene Derivatives; Animals; Anisoles; Central Nervous System Depressants; Disease Models, Animal; Ethanol; Fibrinolytic Agents; Glutamic Acid; Hippocampus; Learning; Male; Memory Disorders; Mice; Mice, Inbred C57BL; Neurotransmitter Agents

Chronic lead (Pb) exposure causes cognitive deficits. This study aimed to explore the neuroprotective effect and mechanism of β-asarone, an active component from Chinese Herbs Acorus tatarinowii Schott, to alleviate impairments of spatial memory and synaptogenesis in Pb-exposed rats. Both Sprague-Dawley developmental rat pups and adult rats were used in the study. Developmental rat pups were exposed to Pb throughout the lactation period and β-asarone (10, 40mg kg-1, respectively) was given intraperitoneally from postnatal day 14 to 21. Also, the adult rats were exposed to Pb from embryo stage to 11 weeks old and β-asarone (2.5, 10, 40mg kg-1, respectively) was given from 9 to 11 weeks old. The level of β-asarone in brain tissue was measured by High Performance Liquid Chromatography. The Morris water maze test and Golgi-Cox staining method were used to assess spatial memory ability and synaptogenesis. The protein expression of NR2B subunit of NMDA receptor, Activity-regulated cytoskeleton-associated protein (Arc/Arg3.1) and Wnt family member 7A (Wnt7a) in hippocampus, as well as mRNA expression of Arc/Arg3.1 and Wnt7a, was also explored. We found that β-asarone could pass through the blood brain barrier quickly. And β-asarone effectively attenuated Pb-induced reduction of spine density in hippocampal CA1 and dentate gyrus areas in a dose-dependent manner both in developmental and adult rats, meanwhile the Pb-induced impairments of learning and memory were partially rescued. In addition, β-asarone effectively up-regulated the protein expression of NR2B, Arc and Wnt7a, as well as the mRNA levels of Arc/Arg3.1 and Wnt7a, which had been suppressed by Pb exposure. The results suggest the neuroprotective properties of β-asarone against Pb-induced memory impairments, and the effect is possibly through the regulation of synaptogenesis, which is mediated via Arc/Arg3.1 and Wnt pathway.

Topics: Acorus; Allylbenzene Derivatives; Animals; Anisoles; Female; Hippocampus; Lead; Male; Maze Learning; Memory Disorders; Neurogenesis; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Spatial Memory; Synapses

Stress is a condition or stimulus that threatens an organism's survival. Noise is an environmental stressor. It is well known that long term as well as acute exposure to noise led to oxidative stress. In the present study, it was investigated that the persistence of noise stress (100 dBA/4 h/d for 30 days) could cause memory impairment in rats and whether ethylacetate extract of AC EAAC (50 mg kg(-1) b.wt.) and alpha-Asarone (9 mg kg(-1) b.wt.). treatment can prevent or not. In order to understand the possible mechanism behind it, antioxidant status and acetylcholinesterase (AChE) activity in hippocampus was evaluated after rats were tested in Radial Eight-arm Maze (RAM). Heat shock protein 70 (hsp 70) expression in hippocampus was also evaluated to understand the intensity of stress level. Results showed that after noise stress exposure, time taken to visit all the baited arms, working and reference memory errors were increased in RAM. The superoxide dismutase, lipid peroxidation, AChE activity, hsp 70 were significantly increased with concomitant decrease in catalase, glutathione peroxidase activity and G6PD activity of non-enzymatic levels was observed in the 30 days noise stress exposed group. When rats were co-administrated with EAAC and alpha-Asarone prevents the noise stress induced alterations significantly. In Conclusion, noise stress induced oxidative stress, increased AChE activity, and over expression of hsp 70 in hippocampus region might have led to the impairment of spatial memory. EAAC and alpha-Asarone prevents this noise stress induced memory impairment.

Topics: Acetylcholinesterase; Acorus; Allylbenzene Derivatives; Animals; Anisoles; Disease Models, Animal; GPI-Linked Proteins; Hippocampus; HSP72 Heat-Shock Proteins; Lipid Peroxidation; Memory; Memory Disorders; Motor Activity; Noise; Nootropic Agents; Oxidative Stress; Phytotherapy; Plant Extracts; Plants, Medicinal; Rats; Rats, Wistar; Stress, Psychological; Superoxide Dismutase; Time Factors