Changrun Guo1, Jinyang Shen2, Zhaoqing Meng3, Xiaolin Yang4, Fei Li5. 1. State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, PR China. Electronic address: crguocpu@126.com. 2. State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, PR China. 3. Jiangsu Kanion Pharmaceutical Co. Ltd., Lianyungang 222001, PR China. 4. Jiangsu Key Laboratory of Research and Development in Marine Bio-resource Pharmaceutics, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, PR China. 5. State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, PR China. Electronic address: lifeicpu@163.com.
Abstract
BACKGROUND: Polygala tenuifolia Willd is a Traditional Chinese Medicine used for the treatment of learning and memory deficits. Triterpenoid saponins, the main bioactive compounds of Polygala tenuifolia Willd, are easily hydrolyzed to polygalacic acid (PA). PURPOSE: The present study was undertaken to investigate the neuroprotective effects of PA on scopolamine-induced cognitive dysfunction and to elucidate its underlying mechanisms of action. METHODS: PA (3, 6, and 12 mg/kg) was administered orally to mice for fourteen days, and scopolamine (1 mg/kg) was injected intraperitoneally for fourteen days to induce memory impairment. Memory-related behaviors were evaluated using the Morris water maze. Cholinergic and neuroinflammatory activities were measured in brain tissue. Superoxide dismutase activities, malondialdehyde and reduced glutathione contents were also measured in the brains. RESULTS: Treatment with scopolamine significantly increased the escape latency time, decreased the number of crossings, and shortened the time spent in the target quadrant, while PA reversed these scopolamine-induced effects. PA significantly improved cholinergic system reactivity, as indicated by decreased acetylcholinesterase (AChE) activity, increased choline acetyltransferase (ChAT) activity, and elevated levels of acetylcholine (ACh) in the hippocampus and frontal cortex. PA also significantly ameliorated neuroinflammation and oxidative stress in mice. CONCLUSION: These results suggest that PA might exert a significant neuroprotective effect on cognitive impairment, driven in part by the modulation of cholinergic activity and neuroinflammation.
BACKGROUND:Polygala tenuifolia Willd is a Traditional Chinese Medicine used for the treatment of learning and memory deficits. Triterpenoidsaponins, the main bioactive compounds of Polygala tenuifolia Willd, are easily hydrolyzed to polygalacic acid (PA). PURPOSE: The present study was undertaken to investigate the neuroprotective effects of PA on scopolamine-induced cognitive dysfunction and to elucidate its underlying mechanisms of action. METHODS:PA (3, 6, and 12 mg/kg) was administered orally to mice for fourteen days, and scopolamine (1 mg/kg) was injected intraperitoneally for fourteen days to induce memory impairment. Memory-related behaviors were evaluated using the Morris water maze. Cholinergic and neuroinflammatory activities were measured in brain tissue. Superoxide dismutase activities, malondialdehyde and reduced glutathione contents were also measured in the brains. RESULTS: Treatment with scopolamine significantly increased the escape latency time, decreased the number of crossings, and shortened the time spent in the target quadrant, while PA reversed these scopolamine-induced effects. PA significantly improved cholinergic system reactivity, as indicated by decreased acetylcholinesterase (AChE) activity, increased choline acetyltransferase (ChAT) activity, and elevated levels of acetylcholine (ACh) in the hippocampus and frontal cortex. PA also significantly ameliorated neuroinflammation and oxidative stress in mice. CONCLUSION: These results suggest that PA might exert a significant neuroprotective effect on cognitive impairment, driven in part by the modulation of cholinergic activity and neuroinflammation.
Authors: Felipe de Paula Nogueira Cruz; Ailton Ferreira de Paula; Camila Tita Nogueira; Paulo Henrique Marques de Andrade; Leonardo Maurici Borges; Paulo Teixeira Lacava; Ilana Lopes Baratella da Cunha Camargo; Fernanda de Freitas Aníbal; Cristina Paiva de Sousa Journal: Int J Microbiol Date: 2021-02-17