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Zhang X, Dai HY, Liu WC, Zeng R, Dai Z, Wang YP, Li JL, Li QZ, Han B. Base-Promoted Formal (3 + 2) Cycloaddition of α-Halohydroxamates with Electron-Deficient Alkenyl-iminoindolines To Synthesize Spiro-indolinepyrrolidinones. J Org Chem 2023; 88:14619-14633. [PMID: 37789599 DOI: 10.1021/acs.joc.3c01619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Construction of pyrrolidinyl-spiroindoles with easily available starting materials has attracted considerable attention from the synthesis community and is in great demand. Here, we describe a base-promoted formal (3 + 2) cycloaddition of α-halohydroxamates with alkenyl-iminoindolines. The present methodology features mild reaction conditions and a broad substrate scope with up to 99% yield and excellent diastereoselectivity. The versatility of this approach is demonstrated through valuable synthetic transformations. Preliminary mechanistic studies shed light on the mechanism of this cycloaddition process.
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Affiliation(s)
- Xiang Zhang
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
| | - Hai-Yu Dai
- School of Mechanical Engineering, Chengdu University, Chengdu 610106, P. R. China
| | - Wan-Cong Liu
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
| | - Rong Zeng
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, P. R. China
| | - Zhen Dai
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
| | - Ya-Peng Wang
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
| | - Jun-Long Li
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
| | - Qing-Zhu Li
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
| | - Bo Han
- Anti-infective Agent Creation Engineering Research Centre of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of pharmacy, Chengdu University, Chengdu 610106, P. R. China
- State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, P. R. China
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Geetha RG, Ramachandran S. Recent Advances in the Anti-Inflammatory Activity of Plant-Derived Alkaloid Rhynchophylline in Neurological and Cardiovascular Diseases. Pharmaceutics 2021; 13:pharmaceutics13081170. [PMID: 34452133 PMCID: PMC8400357 DOI: 10.3390/pharmaceutics13081170] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/21/2021] [Accepted: 07/22/2021] [Indexed: 02/07/2023] Open
Abstract
Rhynchophylline (Rhy) is a plant-derived indole alkaloid isolated from Uncaria species. Both the plant and the alkaloid possess numerous protective properties such as anti-inflammatory, neuroprotective, anti-hypertensive, anti-rhythmic, and sedative effects. Several studies support the significance of the anti-inflammatory activity of the plant as an underlying mechanism for most of the pharmacological activities of the alkaloid. Rhy is effective in protecting both the central nervous system and cardiovascular system. Cerebro-cardiovascular disease primarily occurs due to changes in lifestyle habits. Many previous studies have highlighted the significance of Rhy in modulating calcium channels and potassium channels, thereby protecting the brain from neurodegenerative diseases and related effects. Rhy also has anticoagulation and anti-platelet aggregation activity. Although Rhy has displayed its role in protecting the cardiovascular system, very little is explored about its intervention in early atherosclerosis. Extensive studies are required to understand the cardioprotective effects of Rhye. This review summarized and discussed the various pharmacological effects of Rhy in neuro- and cardioprotection and in particular the relevance of Rhy in preventing early atherosclerosis using Rhy-loaded nanoparticles.
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Qian C, Li P, Sun J. Catalytic Enantioselective Synthesis of Spirooxindoles by Oxidative Rearrangement of Indoles. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202015175] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Chenxiao Qian
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
- Shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of Catalysis College of Science Southern University of Science and Technology Shenzhen 518055 China
| | - Pengfei Li
- Shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of Catalysis College of Science Southern University of Science and Technology Shenzhen 518055 China
| | - Jianwei Sun
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
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Qian C, Li P, Sun J. Catalytic Enantioselective Synthesis of Spirooxindoles by Oxidative Rearrangement of Indoles. Angew Chem Int Ed Engl 2021; 60:5871-5875. [DOI: 10.1002/anie.202015175] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Indexed: 12/12/2022]
Affiliation(s)
- Chenxiao Qian
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
- Shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of Catalysis College of Science Southern University of Science and Technology Shenzhen 518055 China
| | - Pengfei Li
- Shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of Catalysis College of Science Southern University of Science and Technology Shenzhen 518055 China
| | - Jianwei Sun
- Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon, Hong Kong SAR China
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Jung JH, Kim SJ. Anxiolytic Action of Taurine via Intranasal Administration in Mice. Biomol Ther (Seoul) 2019; 27:450-456. [PMID: 30917626 PMCID: PMC6720536 DOI: 10.4062/biomolther.2018.218] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/20/2019] [Accepted: 02/20/2019] [Indexed: 02/02/2023] Open
Abstract
Taurine has a number of beneficial pharmacological actions in the brain such as anxiolytic and neuroprotective actions. We explored to test whether taurine could be transported to the central nervous system through the intranasal route. Following intranasal administration of taurine in mice, elevated plus maze test, activity cage test and rota rod test were carried out to verify taurine's effect on anxiety. For the characterization of potential mechanism of taurine's anti-anxiety action, mouse convulsion tests with strychnine, picrotoxin, yohimbine, and isoniazid were employed. A significant increase in the time spent in the open arms was observed when taurine was administered through the nasal route in the elevated plus maze test. In addition, vertical and horizontal activities of mice treated with taurine via intranasal route were considerably diminished. These results support the hypothesis that taurine can be transported to the brain through intranasal route, thereby inducing anti-anxiety activity. Taurine's anti-anxiety action may be mediated by the strychnine-sensitive glycine receptor as evidenced by the inhibition of strychnine-induced convulsion.
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Affiliation(s)
- Jung Hwa Jung
- Department of Pharmacology and Toxicology and Metabolic Diseases Research Laboratory, School of Dentistry, Kyung Hee University, Seoul 02447,
Republic of Korea
| | - Sung-Jin Kim
- Department of Pharmacology and Toxicology and Metabolic Diseases Research Laboratory, School of Dentistry, Kyung Hee University, Seoul 02447,
Republic of Korea
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Zhang Z, Zhang W, Kang F, Ip FCF, Ip NY, Tong R. Asymmetric Total Syntheses of Rhynchophylline and Isorhynchophylline. J Org Chem 2019; 84:11359-11365. [DOI: 10.1021/acs.joc.9b01977] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Snow AD, Castillo GM, Nguyen BP, Choi PY, Cummings JA, Cam J, Hu Q, Lake T, Pan W, Kastin AJ, Kirschner DA, Wood SG, Rockenstein E, Masliah E, Lorimer S, Tanzi RE, Larsen L. The Amazon rain forest plant Uncaria tomentosa (cat's claw) and its specific proanthocyanidin constituents are potent inhibitors and reducers of both brain plaques and tangles. Sci Rep 2019; 9:561. [PMID: 30728442 PMCID: PMC6365538 DOI: 10.1038/s41598-019-38645-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 01/04/2019] [Indexed: 01/15/2023] Open
Abstract
Brain aging and Alzheimer's disease both demonstrate the accumulation of beta-amyloid protein containing "plaques" and tau protein containing "tangles" that contribute to accelerated memory loss and cognitive decline. In the present investigation we identified a specific plant extract and its constituents as a potential alternative natural solution for preventing and reducing both brain "plaques and tangles". PTI-00703 cat's claw (Uncaria tomentosa from a specific Peruvian source), a specific and natural plant extract from the Amazon rain forest, was identified as a potent inhibitor and reducer of both beta-amyloid fibrils (the main component of "plaques") and tau protein paired helical filaments/fibrils (the main component of "tangles"). PTI-00703 cat's claw demonstrated both the ability to prevent formation/aggregation and disaggregate preformed Aβ fibrils (1-42 and 1-40) and tau protein tangles/filaments. The disaggregation/dissolution of Aβ fibrils occurred nearly instantly when PTI-00703 cat's claw and Aβ fibrils were mixed together as shown by a variety of methods including Thioflavin T fluorometry, Congo red staining, Thioflavin S fluorescence and electron microscopy. Sophisticated structural elucidation studies identified the major fractions and specific constituents within PTI-00703 cat's claw responsible for both the observed "plaque" and "tangle" inhibitory and reducing activity. Specific proanthocyanidins (i.e. epicatechin dimers and variants thereof) are newly identified polyphenolic components within Uncaria tomentosa that possess both "plaque and tangle" reducing and inhibitory activity. One major identified specific polyphenol within PTI-00703 cat's claw was epicatechin-4β-8-epicatechin (i.e. an epicatechin dimer known as proanthocyanidin B2) that markedly reduced brain plaque load and improved short-term memory in younger and older APP "plaque-producing" (TASD-41) transgenic mice (bearing London and Swedish mutations). Proanthocyanidin B2 was also a potent inhibitor of brain inflammation as shown by reduction in astrocytosis and gliosis in TASD-41 transgenic mice. Blood-brain-barrier studies in Sprague-Dawley rats and CD-1 mice indicated that the major components of PTI-00703 cat's claw crossed the blood-brain-barrier and entered the brain parenchyma within 2 minutes of being in the blood. The discovery of a natural plant extract from the Amazon rain forest plant (i.e. Uncaria tomentosa or cat's claw) as both a potent "plaque and tangle" inhibitor and disaggregator is postulated to represent a potential breakthrough for the natural treatment of both normal brain aging and Alzheimer's disease.
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Affiliation(s)
- Alan D Snow
- Cognitive Clarity Inc., Edmonds, WA, USA.
- ProteoTech Inc., Kirkland, WA, USA.
| | | | - Beth P Nguyen
- ProteoTech Inc., Kirkland, WA, USA
- Healthcare Legacy Consulting LLC, Dallas, TX, USA
| | | | - Joel A Cummings
- Cognitive Clarity Inc., Edmonds, WA, USA
- ProteoTech Inc., Kirkland, WA, USA
| | - Judy Cam
- ProteoTech Inc., Kirkland, WA, USA
- Preclinical GPS, Washington University, St. Louis, MO, USA
| | - Qubai Hu
- ProteoTech Inc., Kirkland, WA, USA
| | - Thomas Lake
- Cognitive Clarity Inc., Edmonds, WA, USA
- ProteoTech Inc., Kirkland, WA, USA
| | - Weihong Pan
- Blood-Brain Barrier Laboratory, Pennington Biomedical Research Center at Louisiana State University, Baton Rouge, Louisiana, USA
- Biopotentials Sleep Center, Baton Rouge, LA, USA
| | - Abba J Kastin
- Blood-Brain Barrier Laboratory, Pennington Biomedical Research Center at Louisiana State University, Baton Rouge, Louisiana, USA
| | | | - Steven G Wood
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, UT, USA
| | - Edward Rockenstein
- Departments of Neurosciences and Pathology, University of California- San Diego, La Jolla, CA, USA
| | - Eliezer Masliah
- Departments of Neurosciences and Pathology, University of California- San Diego, La Jolla, CA, USA
- Division of Neurosciences, National Institute on Aging, Bethesda, MD, USA
| | - Stephen Lorimer
- Department of Chemistry, University of Otago, Dunedin, New Zealand
- VicLink Ltd., Wellington, New Zealand
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Lesley Larsen
- Department of Chemistry, University of Otago, Dunedin, New Zealand
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Barringer N, Crombie A, Kotwal R. Impact of a purported nootropic supplementation on measures of mood, stress, and marksmanship performance in U.S. active duty soldiers. J Int Soc Sports Nutr 2018; 15:26. [PMID: 29855372 PMCID: PMC5984413 DOI: 10.1186/s12970-018-0229-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 05/16/2018] [Indexed: 11/25/2022] Open
Abstract
Background The purpose of this study was to determine the impact of a commercially available purported nootropic supplement on mood, stress, and rifle marksmanship accuracy and engagement time via an Engagement Skills Trainer. Methods In this double-blind, placebo-controlled trial, 43 U.S. active duty Soldiers participating in a professional military course were assigned to treatment (n = 20; 16 males and 4 females) or placebo (n = 23; 15 males and 8 females) based on initial marksmanship score. The study period was 31 days (testing performed on days 1 and 31, supplementation days 2 through 30). Participants were instructed to consume 2 pills at breakfast and 1 pill at dinner for a total of 3 pills per day (1925 mg) of either the Alpha Brain® nootropic supplement or a placebo. Height, weight, cortisol (in a hair sample), body composition using multi-frequency tetrapolar bioelectrical impedance (InBody 720), and marksmanship (Engagement Skills Trainer 2000). Marksmanship was assessed in the prone position with zeroed M-4 rifles with a twenty target protocol with targets presenting and remaining for 3 s at set intervals. Participants’ performance were assessed with hits versus misses, distance of hit from target center mass (DCM), and target engagement speed. Statistical analysis via SPSS Statistics 21 (IBM) was conducted using a repeated measures ANOVA with significance set at P < 0.5. Results There was no statistically significant difference between Treatment and Placebo for hits (TreatmentPre 18.5 ± 1.5, TreatmentPost 19.4 ± 0.8, PlaceboPre18.2 ± 2.9, PlaceboPost19.4 ± 1.3), initial reaction time in seconds (TreatmentPre 1.65 ± 0.28, TreatmentPost 1.43 ± 0.28, PlaceboPre1.59 ± 0.29, PlaceboPost1.41 ± 0.21), mean reaction time in seconds (TreatmentPre 1.60 ± 0.20, TreatmentPost 1.41 ± 0.16, PlaceboPre1.61 ± 0.51, PlaceboPost1.46 ± 0.56), or distance from center mass in centimeters (TreatmentPre 11.28 ± 4.28, TreatmentPost 11.92 ± 4.23, PlaceboPre10.52 ± 5.29, PlaceboPost10.94 ± 4.64). A significant time effect (P < 0.5) was found for both groups on all variables except distance from center mass. Reaction time values were adjusted to give percent decrease for initial reaction and mean reaction for the Treatment group (− 12.3% ± 16, − 15.2% ± 21.6) compared to the Placebo group (− 8.3% ± 21.8, − 12.5% ± 23.5), but no significant difference was found. Conclusion The Alpha Brain® nootropic supplement did not have any statistically significant effects on marksmanship performance in this study. Given the rising popularity of nootropic supplements, future research on their potential impact on cognitively demanding soldier tasks, such as target discrimination scenarios, are recommended.
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Affiliation(s)
- Nicholas Barringer
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, 10 General Greene Ave, Natick, MA, 01760, USA.
| | - Aaron Crombie
- U.S. Military-Baylor University Graduate Program in Nutrition, AMEDDC&S HRCoE, 3630 Stanley Rd, Bldg 2841, Suite 0308. Joint Base San Antonio-Fort Sam Houston, San Antonio, TX, 78234, USA
| | - Russ Kotwal
- Department of Defense Joint Trauma System, 3698 Chambers Road, Joint Base San Antonio-Fort Sam Houston, San Antonio, TX, 78234, USA
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Expression of miRNAs in Serum Exosomes versus Hippocampus in Methamphetamine-Induced Rats and Intervention of Rhynchophylline. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2018; 2018:8025062. [PMID: 29636786 PMCID: PMC5832017 DOI: 10.1155/2018/8025062] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 12/26/2017] [Indexed: 01/29/2023]
Abstract
Objective To compare the expressions of miRNAs (microRNAs) in serum exosomes and in hippocampus and to provide insights into the miRNA-mediated relationship between peripheral and central nervous systems in the presence of methamphetamine. Methods Published results on conditioned place preference (CPP) in rats conditioned by methamphetamine were replicated. The expressions of miRNAs in serum exosomes and hippocampus were determined by gene-chip sequencing. We then predicted the potential target genes of selected, differentially expressed (DE) miRNAs and then carried out functional analysis of these target genes. We also verified our results by RT-qPCR. Results Methamphetamine reward could greatly increase the activity time and distance in the intrinsically nonpreferred side of the behavioral apparatus compared with control rats (P < 0.01). Rhynchophylline treatment significantly counteracted these changes (P < 0.01). Methamphetamine-induced CPP upregulated 23 miRNAs (log2 fold change [FC] > 1, P < 0.01) in serum exosomes, whereas rhynchophylline treatment could downregulate these miRNAs (log2 FC < -1, P < 0.01). Analysis of hippocampal miRNAs profiles found 22 DE miRNAs (log2 FC > 1 or <-1, P < 0.01). When methamphetamine induced CPP, 11 of those miRNAs were upregulated, whereas rhynchophylline treatment could downregulate these miRNAs. The other 11 miRNAs behaved in the opposite way. We selected six DE miRNAs from each of serum exosomes and hippocampus for target gene prediction and functional analysis. We found that, in both, the DE miRNAs and their target genes may be related to neuronal information transmission and synaptic transmission. Conclusions Rhynchophylline blocked the alteration of behavior and the expression of some DE miRNAs induced by methamphetamine. The biological functions of these DE miRNAs target genes are correlated between serum exosomes and hippocampus. As to these biological processes and pathways which are involved in the development of addiction at multiple stages, we speculate that these DE miRNAs in serum exosomes and hippocampus are closely related to methamphetamine addiction.
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Lee K, Joo H, Sun M, Kim M, Kim B, Lee BJ, Cho JH, Jung JY, Park JW, Bu Y. Review on the characteristics of liver-pacifying medicinal in relation to the treatment of stroke: from scientific evidence to traditional medical theory. J TRADIT CHIN MED 2018. [DOI: 10.1016/j.jtcm.2018.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Zhu C, Liu W, Luo C, Liu Y, Li C, Fang M, Lin Y, Ou J, Chen M, Zhu D, Yung KKL, Mo Z. Inhibiting effects of rhynchophylline on methamphetamine-dependent zebrafish are related with the expression of tyrosine hydroxylase (TH). Fitoterapia 2017; 117:47-51. [PMID: 28063836 DOI: 10.1016/j.fitote.2017.01.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/02/2017] [Accepted: 01/03/2017] [Indexed: 02/08/2023]
Abstract
In this study, to study the effect of rhynchophylline on TH in midbrain of methamphetamine-induced conditioned place preference (CPP) adult zebrafish, place preference adult zebrafish models were established by methamphetamine (40μg/g) and the expression of TH was observed by immunohistochemistry technique and Western blot. Ketamine (150μg/g), high dose of rhynchophylline (100μg/g) group can significantly reduce the place preference; immunohistochemistry results showed that the number of TH-positive neurons in midbrain was increased in the methamphetamine model group, whereas less TH-positive neurons were found in the ketamine group and high dosage rhynchophylline group. Western blot results showed that the expression of TH protein was significantly increased in the model group, whereas less expression was found in the ketamine group, high dosage rhynchophylline group. Our data pointed out that TH plays an important role in the formation of methamphetamine-induced place preference in adult zebrafish. Rhynchophylline reversed the expression of TH in the midbrain demonstrates the potential effect of mediates methamphetamine induced rewarding effect.
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Affiliation(s)
- Chen Zhu
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Wei Liu
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Chaohua Luo
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Yi Liu
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Chan Li
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Miao Fang
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Yingbo Lin
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Jinying Ou
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Minting Chen
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Daoqi Zhu
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China
| | - Ken Kin-Lam Yung
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong
| | - Zhixian Mo
- School of Traditional Chinese Medicine, Southern Medical University, Guangdong, Guangzhou 510515, China.
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Chowdhury S, Shivani, Kumar S. In vitro anti-acetylcholinesterase activity of an aqueous extract of Unicaria tomentosa and in silico study of its active constituents. Bioinformation 2016; 12:112-118. [PMID: 28149044 PMCID: PMC5267953 DOI: 10.6026/97320630012112] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 03/30/2016] [Indexed: 12/04/2022] Open
Abstract
Depletion of acetylcholine in the central nervous system (CNS) is responsible for memory loss and cognition deficit. Enzyme acetylcholinesterase (AChE) is responsible for destruction of acetylcholine (Ach) in the brain. Many herbal plant extracts have been investigated for their potential use in the treatment of Alzheimer's disease (AD) by inhibiting AChE and upregulating the levels of Ach. The current study investigated the anti-acetylcholinesterase (AChE) activity of an aqueous extract of Unicaria tomentosa bark which has not been reported so far in the literature. The in vitro study of an aqueous extract of U. tomentosa showed maximum inhibition of 76.2±0.002 % at 0.4mg/ml of final concentration with an IC50 = 0.112 mg/ml. The mechanism of inhibition was elucidated by kinetic study which showed mixed type of inhibition, this might be due to the presence of various phytoconstituents such as oxindole alkaloids present in an aqueous extract. Based on molecular structure of phytoconstituents obtained from U. tomentosa known from the relevant literature, in-silico molecular docking study was performed against AChE protein to validate the results.
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Affiliation(s)
- Suman Chowdhury
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Dwarka, New Delhi
| | - Shivani
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Dwarka, New Delhi
| | - Suresh Kumar
- University School of Biotechnology, Guru Gobind Singh Indraprastha University, Dwarka, New Delhi
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Zhang Y, Sun J, Zhu S, Xu T, Lu J, Han H, Zhou C, Yan J. The role of rhynchophylline in alleviating early brain injury following subarachnoid hemorrhage in rats. Brain Res 2015; 1631:92-100. [PMID: 26631843 DOI: 10.1016/j.brainres.2015.11.035] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 11/20/2015] [Accepted: 11/21/2015] [Indexed: 12/30/2022]
Abstract
Rhynchophylline (Rhy) has been demonstrated protective effects on some neurological diseases. However, the roles of Rhy in the subarachnoid hemorrhage (SAH) are still to be cleared. In the present study, the effects of Rhy on attenuation of early brain injury (EBI) after SAH have been evaluated. The adult male Sprague-Dawley rats (280-300g) were used to establish the SAH models using endovascular perforation method. Rhy was administered by intraperitoneal injection immediately following SAH. Brain edema was assessed by magnetic resonance imaging (MRI) at 24h after SAH. Neurological deficits, brain water content, malondialdehyde (MDA) concentration, myeloperoxidase (MPO) activity and reactive oxygen species (ROS) content in hippocampus were also evaluated. Immunofluorescence and western blot were used to explore the underlying protective mechanism of Rhy. The results showed that, following 10mg/kg Rhy treatment, the brain edema and neurological deficits, and blood-brain barrier (BBB) disruption were significantly attenuated at 24h after SAH. Additionally, in hippocampus, MDA concentration, MPO activity and ROS content were markedly decreased. Meanwhile, the levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidoreductase (NQO-1) were increased, while the expressions of p-p53, cleaved-caspase-3 and tumor necrosis factor-α (TNF-α) were significantly decreased. Our results indicated that Rhy could attenuate early brain injury by reducing inflammation and apoptosis in hippocampus after SAH.
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Affiliation(s)
- Yan Zhang
- Department of Anatomy and Histology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Juan Sun
- Department of Anatomy and Histology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Shijie Zhu
- Department of Anatomy, School of Basic Medical Sciences, GuiYang College of Traditional Chinese Medicine, Guiyang, China
| | - Ting Xu
- Department of Anatomy and Histology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Jianfei Lu
- Department of Anatomy and Histology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Hongbin Han
- Department of Radiology, Peking University Third Hospital, Beijing 100191, China; Beijing Key Lab of Magnetic Resonance Imaging Technology, Beijing 100191, China
| | - Changman Zhou
- Department of Anatomy and Histology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China
| | - Junhao Yan
- Department of Anatomy and Histology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, China; Beijing Key Lab of Magnetic Resonance Imaging Technology, Beijing 100191, China.
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Abstract
Alzheimer's disease (AD) is a neurodegenerative illness associated with dementia and is most prevalent among the elderly population. Current medications can only treat symptoms. Alkaloids are structurally diverse and have been an important source of therapeutics for various brain disorders. Two US Food and Drug Administration (FDA)-approved acetylcholinesterase inhibitors for AD, galantamine and rivastigmine, are in fact alkaloids. In addition, clinical trials of four other extensively studied alkaloids-huperzine A, caffeine, nicotine, and indomethacin-have been conducted but do not convincingly demonstrate their clinical efficacy for AD. Interestingly, rhynchophylline, a known neuroprotective alkaloid, was recently discovered by in silico screening as an inhibitor of EphA4, a novel target for AD. Here, we review the pathophysiological mechanisms underlying AD, current treatment strategies, and therapeutic potential of several selected plant alkaloids in AD, highlighting their various drug targets and the key supportive preclinical and clinical studies. Future research should include more rigorous clinical studies of the most promising alkaloids, the further development of recently discovered candidate alkaloids, and the continual search for new alkaloids for relevant drug targets. It remains promising that an alkaloid drug candidate could significantly affect the progression of AD in addition to providing symptomatic relief.
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Affiliation(s)
- Yu Pong Ng
- Division of Life Science, Molecular Neuroscience Center, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Terry Cho Tsun Or
- Division of Life Science, Molecular Neuroscience Center, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
| | - Nancy Y Ip
- Division of Life Science, Molecular Neuroscience Center, State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
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Ahmad R, Salim F. Oxindole Alkaloids of Uncaria (Rubiaceae, Subfamily Cinchonoideae). STUDIES IN NATURAL PRODUCTS CHEMISTRY 2015. [DOI: 10.1016/b978-0-444-63473-3.00012-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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16
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Li J, Liu W, Peng Q, Jiang M, Luo C, Guo Y, Liu Y, Fang M, Mo Z. Effect of rhynchophylline on conditioned place preference on expression of NR2B in methamphetamine-dependent mice. Biochem Biophys Res Commun 2014; 452:695-700. [PMID: 25193707 DOI: 10.1016/j.bbrc.2014.08.127] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 08/25/2014] [Indexed: 01/23/2023]
Abstract
OBJECTIVE To study the effect of rhynchophylline on N-methyl d-aspartate receptor subtype 2B subunit in hippocampus of Methamphetamine-induced conditioned place preference (CPP) mice. METHODS Place preference mice models were established by methamphetamine; the expression of NR2B was observed by immunohistochemistry technique and Western blot. RESULTS Methamphetamine (4mg/kg)-induced place preference mice model was successfully established; ketamine (15mg/kg), rhynchophylline (40mg/kg) and rhynchophylline (80mg/kg) can eliminate place preference; Immunohistochemistry showed that the number of NR2B-positive neurons in hippocampus was increased in the methamphetamine model group, whereas less NR2B-positive neurons were found in the ketamine group, low and high dosage rhynchophylline group. Western blot showed that the expression of NR2B protein was significantly increased in the model group, whereas less expression was found in the ketamine group, low and high dosage rhynchophylline group. CONCLUSIONS NR2B plays an important role in the formation of methamphetamine-induced place preference in mice. Rhynchophylline reversed the expression of NR2B in the hippocampus demonstrates the potential effect of mediates methamphetamine induced rewarding effect.
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Affiliation(s)
- Junkui Li
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Wei Liu
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Qiuxian Peng
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China; Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong
| | - Mingjin Jiang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Chaohua Luo
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Youli Guo
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Yi Liu
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Miao Fang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Zhixian Mo
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China.
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Huang H, Zhong R, Xia Z, Song J, Feng L. Neuroprotective effects of rhynchophylline against ischemic brain injury via regulation of the Akt/mTOR and TLRs signaling pathways. Molecules 2014; 19:11196-210. [PMID: 25079660 PMCID: PMC6270871 DOI: 10.3390/molecules190811196] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/06/2014] [Accepted: 07/16/2014] [Indexed: 12/12/2022] Open
Abstract
Rhynchophylline (Rhy) is an alkaloid isolated from Uncaria which has long been recommended for the treatment of central nervous diseases. In our study, the neuroprotective effect of Rhy was investigated in a stroke model, namely permanent middle cerebral artery occlusion (pMCAO). Rats were injected intraperitoneally once daily for four consecutive days before surgery and then received one more injection after surgery. The protein and mRNA levels of p-Akt, p-mTOR, apoptosis-related proteins (p-BAD and cleaved caspase-3), TLR2/4/9, NF-κB, MyD88, BDNF and claudin-5 were examined. Following pMCAO, Rhy treatment not only ameliorated neurological deficits, infarct volume and brain edema, but also increased claudin-5 and BDNF expressions (p < 0.05). Moreover, Rhy could activate PI3K/Akt/mTOR signaling while inhibiting TLRs/NF-κB pathway. Wortmannin, a selective PI3K inhibitor, could abolish the neuroprotective effect of Rhy and reverse the increment in p-Akt, p-mTOR and p-BAD levels. In conclusion, we hypothesize that Rhy protected against ischemic damage, probably via regulating the Akt/mTOR pathway.
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Affiliation(s)
- Houcai Huang
- Animal Center, Jiangsu Provincial Academy of Chinese Medicine, Jiangsu, Nanjing 210028, China.
| | - Rongling Zhong
- Animal Center, Jiangsu Provincial Academy of Chinese Medicine, Jiangsu, Nanjing 210028, China.
| | - Zhi Xia
- Animal Center, Jiangsu Provincial Academy of Chinese Medicine, Jiangsu, Nanjing 210028, China.
| | - Jie Song
- Key Laboratory of Delivery Systems of Chinese Meteria Medica, Jiangsu Provincial Academy of Chinese Medicine, Jiangsu, Nanjing 210028, China.
| | - Liang Feng
- Key Laboratory of Delivery Systems of Chinese Meteria Medica, Jiangsu Provincial Academy of Chinese Medicine, Jiangsu, Nanjing 210028, China.
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19
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Biologically Active Compounds from the Genus Uncaria (Rubiaceae). STUDIES IN NATURAL PRODUCTS CHEMISTRY 2014. [DOI: 10.1016/b978-0-444-63430-6.00013-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Liu W, Peng QX, Lin XL, Luo CH, Jiang MJ, Mo ZX, Yung KKL. Effect of rhynchophylline on the expression of p-CREB and sc-Fos in triatum and hippocampal CA1 area of methamphetamine-induced conditioned place preference rats. Fitoterapia 2013; 92:16-22. [PMID: 24140441 DOI: 10.1016/j.fitote.2013.10.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Revised: 09/30/2013] [Accepted: 10/05/2013] [Indexed: 02/04/2023]
Abstract
To explore the effect of rhynchophylline (Rhy) on the expression of p-CREB and c-Fos in the striatum and hippocampal CA1 area of methamphetamine-induced conditioned place preference (CPP) rat, methamphetamine (2 mg/kg) was injected to rats and the conditioned place preference was observed in these rats treated with or without Rhy. An immunohistochemistry assay was used to determine the expression of p-CREB and c-Fos in the striatum and hippocampal CA1 area. Methamphetamine induced significant behavior alteration in CPP, while after pretreatment with rhynchophylline or ketamine, the time of staying in methamphetamine-paired compartment of rats was significantly reduced. Methamphetamine also increased the number of p-CREB positive cells in the striatum and hippocampal CA1 zone, as well as p-Fos positive cells. However, the compound Rhy could attenuate the effect. These findings show that Rhy can suppress the acquisition of CPP in rats induced by methamphetamine and the action may be related with the reduced expression of p-CREB and p-Fos in the striatum and hippocampus.
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Affiliation(s)
- Wei Liu
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Qiu-Xian Peng
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong
| | - Xiao-Liang Lin
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Chao-Hua Luo
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Ming-Jin Jiang
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China
| | - Zhi-Xian Mo
- School of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China.
| | - Ken Kin-Lam Yung
- Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong.
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Bigliani MC, Rosso MC, Zunino PM, Baiardi G, Ponce AA. Anxiogenic-like effects ofUncariatomentosa(Willd.) DC. aqueous extract in an elevated plus maze test in mice: a preliminary study. Nat Prod Res 2013; 27:1682-5. [DOI: 10.1080/14786419.2012.761617] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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22
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Lee B, Sur B, Park J, Shin H, Kwon S, Yeom M, Kim SJ, Kim K, Shim I, Yin CS, Lee H, Hahm DH. Fucoidan ameliorates scopolamine-induced neuronal impairment and memory dysfunction in rats via activation of cholinergic system and regulation of cAMP-response element-binding protein and brain-derived neurotrophic factor expressions. ACTA ACUST UNITED AC 2012. [DOI: 10.1007/s13765-012-2137-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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23
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Lee B, Sur B, Cho S, Yeom M, Shim I, Lee H, Hahm DH. Protective effect ofPhellodendri Cortexagainst lipopolysaccharide-induced memory impairment in rats. Anim Cells Syst (Seoul) 2012. [DOI: 10.1080/19768354.2012.699004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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24
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Yang PH, Qu CT, Wang WZ. AcOH catalyzed three-component synthesis of spirooxindole derivatives. RESEARCH ON CHEMICAL INTERMEDIATES 2012. [DOI: 10.1007/s11164-012-0570-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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25
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Lee B, Sur B, Shim I, Lee H, Hahm DH. Phellodendron amurense and Its Major Alkaloid Compound, Berberine Ameliorates Scopolamine-Induced Neuronal Impairment and Memory Dysfunction in Rats. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2012; 16:79-89. [PMID: 22563252 PMCID: PMC3339292 DOI: 10.4196/kjpp.2012.16.2.79] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 02/17/2012] [Accepted: 03/03/2012] [Indexed: 01/06/2023]
Abstract
We examine whether Phellodendron amurense (PA) and its major alkaloid compound, berberine (BER), improved memory defects caused by administering scopolamine in rats. Effects of PA and BER on the acetylcholinergic system and pro-inflammatory cytokines in the hippocampus were also investigated. Male rats were administered daily doses for 14 days of PA (100 and 200 mg/kg, i.p.) and BER (20 mg/kg, i.p.) 30 min before scopolamine injection (2 mg/kg, i.p.). Daily administration of PA and BER improved memory impairment as measured by the passive avoidance test and reduced the escape latency for finding the platform in the Morris water maze test. Administration of PA and BER significantly alleviated memory-associated decreases in cholinergic immunoreactivity and restored brain-derived neurotrophic factor and cAMP-response element-binding protein mRNA expression in the hippocampus. PA and BER also decreased significantly the expression of proinflammatory cytokines such as interleukin-1β, tumor necrosis factor-α and cyclooxygenase-2 mRNA in the hippocampus. These results demonstrated that PA and BER had significant neuroprotective effects against neuronal impairment and memory dysfunction caused by scopolamine in rats. These results suggest that PA and BER may be useful as therapeutic agents for improving cognitive functioning by stimulating cholinergic enzyme activity and alleviating inflammatory responses.
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Affiliation(s)
- Bombi Lee
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Bongjun Sur
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Insop Shim
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Hyejung Lee
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
| | - Dae-Hyun Hahm
- Acupuncture and Meridian Science Research Center, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
- The Graduate School of Basic Science of Oriental Medicine, College of Oriental Medicine, Kyung Hee University, Seoul 130-701, Korea
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Zhou JY, Zhou SW. Isorhynchophylline: A plant alkaloid with therapeutic potential for cardiovascular and central nervous system diseases. Fitoterapia 2012; 83:617-26. [PMID: 22406453 DOI: 10.1016/j.fitote.2012.02.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 02/20/2012] [Accepted: 02/22/2012] [Indexed: 11/19/2022]
Abstract
Uncaria species (Gouteng in Chinese) have been used as a plant medicine to treat ailments of cardiovascular and central nervous systems. As the main alkaloid constituent of Uncaria species, isorhynchophylline has drawn extensive attention toward antihypertensive and neuroprotective activities in recent years. Isorhynchophylline mainly acts on cardiovascular and central nervous systems diseases including hypertension, brachycardia, arrhythmia, and sedation, vascular dementia, and amnesia. Isorhynchophylline also has effects on anticoagulation, inhibition vascular smooth muscle cell apoptosis and proliferation, anti-multidrug resistant of lung cells, anti-endotoxemic, and antispasmodic. The active mechanisms are related to modulation on calcium ion channel, protection neural and neuroglial cells against β-amyloid(25-35)-induced neurotoxicity and via inducing autophagy. As a candidate drug of several cardiovascular and central nervous systems diseases, isorhynchophylline will attract scientists to pursue the potential related pharmacological effects and its mechanism with new technologies. But relatively few clinical application of isorhynchophylline has been conducted on its pharmacological activities. It requires more in vivo validations and further investigations of antihypertensive and neuroprotective mechanisms of isorhynchophylline.
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Affiliation(s)
- Ji-Yin Zhou
- Base for Drug Clinical Trial, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China
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27
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Increased expression of β amyloid precursor gene in the hippocampus of streptozotocin-induced diabetic mice with memory deficit and anxiety induction. J Neural Transm (Vienna) 2010; 117:1411-8. [PMID: 21069392 DOI: 10.1007/s00702-010-0516-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Accepted: 10/19/2010] [Indexed: 10/18/2022]
Abstract
Diabetes has been associated with memory and behavioral dysfunctions such as anxiety. However, exact mechanisms of how diabetes affect such changes remain to be characterized. The purpose of present study is to search for streptozotocin-regulated genes in hippocampus of the mice using a differential display PCR technique, in the hope of type I diabetes-related hippocampal gene(s). It has been found that expression of a PCR product was increased by streptozotocin treatment and it was identified as β amyloid precursor protein. These results were further confirmed by performing RT-PCR analysis. In addition, the protein expression of β amyloid precursor protein as evidenced by Western blot analysis was increased in the hippocampus of streptozotocin-induced diabetic mice. To explore if the changes in amyloid β precursor protein could be related with functional changes in the brain regarding memory activity and anxiety, passive avoidance test and elevated plus maze test were performed, respectively. There is significant reduction of memory formation and marked induction of anxiety in the streptozotocin-induced diabetic mice. These results suggest that increase of β amyloid precursor protein may play a role in the memory loss and anxiety induction in type I diabetic mice.
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Zhou J, Zhou S. Antihypertensive and neuroprotective activities of rhynchophylline: the role of rhynchophylline in neurotransmission and ion channel activity. JOURNAL OF ETHNOPHARMACOLOGY 2010; 132:15-27. [PMID: 20736055 DOI: 10.1016/j.jep.2010.08.041] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 08/14/2010] [Accepted: 08/17/2010] [Indexed: 05/29/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Uncaria species (Gouteng in Chinese) have been used as ethnopharmacological medicines to treat ailments of the cardiovascular and central nervous systems. As the main alkaloid constituent of Uncaria species, rhynchophylline has drawn extensive attention in recent years for its antihypertensive and neuroprotective activities, and its pharmacological effects are related to ethnopharmacological medicine properties of Uncaria species. AIM OF THE REVIEW This review examined the pharmacological studies and mechanisms of rhynchophylline, with an emphasis on cardiovascular and central nervous system diseases linked to the ethnopharmacological uses of Uncaria species. METHODS We conducted both an electronic search and a library search of in vivo and in vitro studies. The terms and keywords for the search included rhynchophylline, Uncaria species, Gouteng, pharmacological effects, and mechanism. We focused on the papers, including ours, with studies on all related pharmacological effects and mechanisms of rhynchophylline. RESULTS Rhynchophylline was the main constituent of several components identified from Uncaria species. Rhynchophylline mainly acts on cardiovascular and central nervous system diseases, including hypertension, bradycardia, arrhythmia, sedation, vascular dementia, epileptic seizures, drug addiction, and cerebral ischemia. Rhynchophylline also has effects on anticoagulation, inhibits vascular smooth muscle cell proliferation, and has been shown to be anti-endotoxemic. The active mechanisms are related to modulation of calcium and potassium ion channels, protection of neural and neuroglial cells, and regulation of central neurotransmitter transport and metabolism. More studies are necessary to verify the pharmacological activities and determine the exact mechanisms of rhynchophylline activity. CONCLUSIONS Rhynchophylline treatment of cardiovascular and central nervous system diseases has a strong linkage with traditional concepts and uses of Uncaria species in ethnopharmacological medicine, such as treatment for lightheadedness, convulsions, numbness, and hypertension. As a candidate drug for several cardiovascular and central nervous system diseases, rhynchophylline will attract scientists to pursue the potential pharmacological effects and mechanisms with new technologies. Relatively few clinically relevant studies of rhynchophylline have been conducted. Thus, more in vivo validations and investigations of antihypertensive and neuroprotective mechanisms of rhynchophylline are necessary.
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Affiliation(s)
- Jiyin Zhou
- Base for Drug Clinical Trial, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China.
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29
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Zhang Y, Panek JS. Stereocontrolled synthesis of spirooxindoles through Lewis acid-promoted [5 + 2]-annulation of chiral silyl alcohols. Org Lett 2009; 11:3366-9. [PMID: 19719185 DOI: 10.1021/ol901202t] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The enantioselective synthesis of stereochemically and structurally diverse spirocyclic oxindoles by [5 + 2]-annulation of chiral crotylsilanes bearing a primary alcohol is described. The annulation products were further elaborated to polycyclic oxindoles by Pd(0) catalysis.
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Affiliation(s)
- Yun Zhang
- Department of Chemistry, Metcalf Center for Science and Engineering, Boston University, 590 Commonwealth Avenue, Boston, Massachusetts 02215, USA
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30
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Gomes NGM, Campos MG, Orfão JMC, Ribeiro CAF. Plants with neurobiological activity as potential targets for drug discovery. Prog Neuropsychopharmacol Biol Psychiatry 2009; 33:1372-89. [PMID: 19666075 DOI: 10.1016/j.pnpbp.2009.07.033] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 07/31/2009] [Accepted: 07/31/2009] [Indexed: 12/21/2022]
Abstract
Significant number of studies has been performed to find alternatives or treatments for diseases of the nervous forum by identifying structures with activity at the central nervous system (CNS). However most of the screenings are usually conducted on an ad hoc basis and not systematically. The initial purpose of this review was to screen plants with neurological bioactivity, in particular those that have not been fully studied and that have molecular mechanisms whose active constituents responsible for the activity remain to be identified. The second purpose was to identify potential target plants for future studies of new and alternative therapies for the treatment of neurological disorders and neurodegenerative diseases. All plants considered in this review were selected for three qualities: possible molecular requirements to act at the CNS; representative of the main classes of compounds with the referred bioactivity and the major families containing species with those compounds; and diffuse world distribution. We identified several examples of plants that have potential for further study. We have included the main families of these plants, their known molecular mechanisms involved in neurological bioactivity, and the active constituents responsible for such activity. Also included is a brief discussion about the requirements of the different compounds to reach the CNS. These requirements may be less limited than what researchers have previously thought.
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Affiliation(s)
- Nelson G M Gomes
- Center of Pharmaceutical Studies, Laboratory of Pharmacognosy, Faculty of Pharmacy, University of Coimbra, Polo III, Azinhaga de Santa Comba, Coimbra, Portugal.
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Saraf M, Prabhakar S, Anand A. Bacopa monniera alleviates Nω-nitro-l-arginine-induced but not MK-801-induced amnesia: A mouse Morris water maze study. Neuroscience 2009; 160:149-55. [DOI: 10.1016/j.neuroscience.2009.02.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2008] [Revised: 02/03/2009] [Accepted: 02/04/2009] [Indexed: 11/28/2022]
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Zhang CG, Kim SJ. Taurine Induces Anti-Anxiety by Activating Strychnine-Sensitive Glycine Receptor in vivo. ANNALS OF NUTRITION AND METABOLISM 2007; 51:379-86. [PMID: 17728537 DOI: 10.1159/000107687] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Accepted: 03/09/2007] [Indexed: 11/19/2022]
Abstract
Taurine has a variety of actions in the body such as cardiotonic, host-defensive, radioprotective and glucose-regulatory effects. However, its action in the central nervous system remains to be characterized. In the present study, we tested to see whether taurine exerts anti-anxiety effects and to explore its mechanism of anti-anxiety activity in vivo. The staircase test and elevated plus maze test were performed to test the anti-anxiety action of taurine. Convulsions induced by strychnine, picrotoxin, yohimbine and isoniazid were tested to explore the mechanism of anti-anxiety activity of taurine. The Rotarod test was performed to test muscle relaxant activity and the passive avoidance test was carried out to test memory activity in response to taurine. Taurine (200 mg/kg, p.o.) significantly reduced rearing numbers in the staircase test while it increased the time spent in the open arms as well as the number of entries to the open arms in the elevated plus maze test, suggesting that it has a significant anti-anxiety activity. Taurine's action could be due to its binding to and activating of strychnine-sensitive glycine receptor in vivo as it inhibited convulsion caused by strychnine; however, it has little effect on picrotoxin-induced convulsion, suggesting its anti-anxiety activity may not be linked to GABA receptor. It did not alter memory function and muscle activity. Taken together, these results suggest that taurine could be beneficial for the control of anxiety in the clinical situations.
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Affiliation(s)
- Cheng Gao Zhang
- Department of Pharmacology and Metabolic Diseases Research Laboratory, School of Dentistry, Kyung Hee University, Seoul, Korea
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Matsumoto K, Morishige R, Murakami Y, Tohda M, Takayama H, Sakakibara I, Watanabe H. Suppressive effects of isorhynchophylline on 5-HT2A receptor function in the brain: Behavioural and electrophysiological studies. Eur J Pharmacol 2005; 517:191-9. [PMID: 15963493 DOI: 10.1016/j.ejphar.2005.05.015] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2005] [Accepted: 05/20/2005] [Indexed: 11/26/2022]
Abstract
Isorhynchophylline is a major oxindole alkaloid found in Uncaria species which have long been used in traditional Chinese medicine. Here, we investigated the effects of isorhynchophylline and isorhynchophylline-related alkaloids on 5-hydroxytryptamine (5-HT) receptor-mediated behavioural responses in mice and 5-HT-evoked current responses in Xenopus oocytes expressing 5-HT2A or 5-HT2C receptors. Isorhynchophylline dose-dependently inhibited 5-HT2A receptor-mediated head-twitch but not 5-HT1A receptor-mediated head-weaving responses evoked by 5-methoxy-N,N-dimethyltryptamine. Pretreatment with reserpine, a monoamine-depleting agent, enhanced the head-twitching, but did not influence the effect of isorhynchophylline on the behavioural response. Isocorynoxeine, an isorhynchophylline-related alkaloid in which the configuration of the oxindole moiety is the same as in isorhynchophylline, also reduced the head-twitch response in reserpinized mice over the same dose range as isorhynchophylline, while both rhynchophylline and corynoxeine, stereoisomers of isorhynchophylline and isocorynoxeine, did not. None of the alkaloids tested had an effect on meta-chlorophenylpiperazine-induced hypolocomotion, a 5-HT2C receptor-mediated behavioural response. In experiments in vitro, isorhynchophylline and isocorynoxeine dose-dependently and competitively inhibited 5-HT-evoked currents in Xenopus oocytes expressing 5-HT2A receptors, but had less of a suppressive effect on those in oocytes expressing 5-HT2C receptors. These results indicate that isorhynchophylline and isocorynoxeine preferentially suppress 5-HT2A receptor function in the brain probably via a competitive antagonism at 5-HT2A receptor sites and that the configuration of the oxindole moiety of isorhynchophylline is essential for their antagonistic activity at the 5-HT2A receptor.
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MESH Headings
- Alkaloids/pharmacology
- Aminopyridines/pharmacology
- Animals
- Behavior, Animal/drug effects
- Brain/drug effects
- Brain/physiology
- Dose-Response Relationship, Drug
- Female
- Indole Alkaloids
- Ketanserin/pharmacology
- Male
- Membrane Potentials/drug effects
- Methoxydimethyltryptamines/pharmacology
- Mianserin/pharmacology
- Mice
- Mice, Inbred ICR
- Motor Activity/drug effects
- Oocytes/drug effects
- Oocytes/physiology
- Oxindoles
- Patch-Clamp Techniques
- Piperazines/pharmacology
- Rats
- Receptor, Serotonin, 5-HT2A/genetics
- Receptor, Serotonin, 5-HT2A/physiology
- Receptor, Serotonin, 5-HT2C/genetics
- Receptor, Serotonin, 5-HT2C/physiology
- Serotonin/pharmacology
- Serotonin 5-HT2 Receptor Antagonists
- Serotonin Antagonists/pharmacology
- Xenopus
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Affiliation(s)
- Kinzo Matsumoto
- Division of Medicinal Pharmacology, Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan.
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34
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Kang TH, Murakami Y, Takayama H, Kitajima M, Aimi N, Watanabe H, Matsumoto K. Protective effect of rhynchophylline and isorhynchophylline on in vitro ischemia-induced neuronal damage in the hippocampus: putative neurotransmitter receptors involved in their action. Life Sci 2004; 76:331-43. [PMID: 15531384 DOI: 10.1016/j.lfs.2004.08.012] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2004] [Accepted: 08/05/2004] [Indexed: 11/24/2022]
Abstract
Rhynchophylline and isorhynchophylline are major tetracyclic oxindole alkaloid components of Uncaira species, which have been long used as medicinal plants. In this study we examined the protective effects of rhynchophylline and isorhynchophylline on in vitro ischemia-induced neuronal damage in the hippocampus and interaction of these alkaloids with neurotransmitter receptors in a receptor expression model of Xenopus oocytes. In vitro ischemia was induced by exposing the hippocampal slices to oxygen- and D-glucose-deprived medium over 8 min. The resultant neuronal damage was elucidated as deterioration of population spike (PS) amplitudes evoked trans-synaptically by electrical stimulation of Schaffer collaterals and recorded in the CA1 area. Rhynchophylline and isorhynchophylline, as well as the N-methyl-D-aspartate (NMDA) antagonist (+/-)-2-amino-5-phosphono-valeric acid (APV), the muscarinic M1 receptor antagonist pirenzepine, and the 5-HT2 receptor antagonist ketanserin, attenuated the in vitro ischemia-induced neuronal damage in a concentration-dependent manner. There was no difference in the extent of protection against the neuronal damage between rhynchophylline and isorhynchophylline treatment. In Xenopus oocytes expressing the rat brain receptors encoded by total RNA, both rhynchophylline and isorhynchophylline reduced muscarinic receptor- and 5-HT2 receptor-mediated current responses in a competitive manner. Together with our previous findings that rhynchophylline and isorhynchophylline have a non-competitive antagonistic effect on the NMDA-type ionotropic glutamate receptors, the present results suggest that these alkaloids exert their protective action against ischemia-induced neuronal damage by preventing NMDA, muscarinic M1, and 5-HT2 receptors-mediated neurotoxicity during ischemia.
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Affiliation(s)
- Tai-Hyun Kang
- Division of Pharmacology, Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan
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35
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Zhang ZJ. Therapeutic effects of herbal extracts and constituents in animal models of psychiatric disorders. Life Sci 2004; 75:1659-99. [PMID: 15268969 DOI: 10.1016/j.lfs.2004.04.014] [Citation(s) in RCA: 210] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Accepted: 04/07/2004] [Indexed: 11/18/2022]
Abstract
A search for novel pharmacotherapy from medicinal plants for psychiatric illnesses has progressed significantly in the past decade. This is reflected in the large number of herbal preparations for which psychotherapeutic potential has been evaluated in a variety of animal models. The objective of this review is to provide an overview of herbal extracts and constituents that have significant therapeutic effects in animal models of psychiatric illnesses. Eighty five individual herbs reviewed were classified as anxiolytic, antidepressant, neuroleptic, antidementia, or anti-substance abuse herbs. The full scientific name of each herb, herbal part used, active constituent, extract, dose range and route, animal model, possible mechanisms of action, and pertinent references are presented via synoptic tables. The herbal mixtures were also mentioned. A considerable number of herbal constituents whose behavioral effects and pharmacological actions have been well characterized may be good candidates for further investigations that may ultimately result in clinical use. The investigation of a large portion of the herbal extracts and herbal mixtures is in its infancy. Herbal remedies that have demonstrable psychotherapeutic activities have provided a potential to psychiatric pharmaceuticals and deserve increased attention in future studies.
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Affiliation(s)
- Zhang-Jin Zhang
- Department of Psychiatry, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
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36
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Lee SC, Linh PT, Jing Z, Ryu SY, Myung CS, Kim YH, Kang JS. Effects of repeated administration of Uncaria hooks on the acquisition and central neuronal activities in ethanol-treated mice. JOURNAL OF ETHNOPHARMACOLOGY 2004; 94:123-128. [PMID: 15261972 DOI: 10.1016/j.jep.2004.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2004] [Revised: 03/29/2004] [Accepted: 05/06/2004] [Indexed: 05/24/2023]
Abstract
The effects of the repeated administration of Uncaria hooks were examined on the impaired memory acquisition and the level of neurotransmitters in the cortex, hippocampus and striatum in ethanol-treated mice, in comparison with those with L-deprenyl and N-methyl-D-glucamine as positive controls. Ethanol-induced amnesia was significantly ameliorated by repeated administration of methanol extract and alkaloid fraction of Uncaria hooks, similar to in the positive controls. Treatment with methanol extract and alkaloid fraction of Uncaria hooks significantly reduced the ethanol-induced increase of dopamine in the hippocampus. The 5-hydroxytryptamine and glutamic acid neuronal activities were significantly changed by Uncaria hooks, but not by L-deprenyl, in all examined brain tissues of ethanol-treated mice. On the other hand, the GABAergic and cholinergic neuronal activities did not show any significant changes by Uncaria hooks in any of the examined brain tissues of the ethanol-treated animals. The results suggest that the extracts of Uncaria hooks exert a beneficial effect on ethanol-induced memory impairment, and that the central 5-hydroxytryptaminergic and glutaminergic neuronal systems play an important role in the memory acquisition of Uncaria hooks.
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Affiliation(s)
- Soon Chul Lee
- Dental School, University of Maryland, Baltimore 21201, USA
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37
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Kang TH, Murakami Y, Matsumoto K, Takayama H, Kitajima M, Aimi N, Watanabe H. Rhynchophylline and isorhynchophylline inhibit NMDA receptors expressed in Xenopus oocytes. Eur J Pharmacol 2002; 455:27-34. [PMID: 12433591 DOI: 10.1016/s0014-2999(02)02581-5] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Rhynchophylline and isorhynchophylline are major tetracyclic oxindole alkaloid components of Uncaira species, which have been long used as medicinal plants. In this study, the effects of rhynchophylline and isorhynchophylline on the ionotropic and metabotropic glutamate receptor-mediated current responses were examined using Xenopus oocytes injected with total RNA prepared from rat cortices or cerebelli. Rhynchophylline and isorhynchophylline (1-100 microM) per se failed to induce membrane current, but these alkaloids reversibly reduced N-methyl-D-aspartate (NMDA)-induced current in a concentration-dependent but voltage-independent manner. The IC(50) values of rhynchophylline and isorhynchophylline were 43.2 and 48.3 microM, respectively. Substitution of Ba(2+) for Ca(2+) in the recording medium did not alter the extent of rhynchophylline- and isorhynchophylline-induced suppression of NMDA currents. In contrast, neither alkaloid had an effect on the currents mediated by ionotropic kainic acid-type and (+/-)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptors or by the metabotropic glutamate receptor(1 and 5) (mGlu(1/5)). Rhynchophylline and isorhynchophylline (30 microM) significantly reduced the maximal current responses evoked by NMDA and glycine (a co-agonist of NMDA receptor), but had no effect on the EC(50) values and Hill coefficients of NMDA and glycine for inducing currents. These alkaloids showed no interaction with the polyamine binding site, the Zn(2+) site, proton site or redox modulatory site on the NMDA receptor. These results suggest that rhynchophylline and isorhynchophylline act as noncompetitive antagonists of the NMDA receptor and that this property may contribute to the neuroprotective and anticonvulsant activity of the Uncaira species plant extracts.
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Affiliation(s)
- Tai-Hyun Kang
- Department of Pharmacology, Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama 930-0194, Japan
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38
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Kang TH, Matsumoto K, Tohda M, Murakami Y, Takayama H, Kitajima M, Aimi N, Watanabe H. Pteropodine and isopteropodine positively modulate the function of rat muscarinic M(1) and 5-HT(2) receptors expressed in Xenopus oocyte. Eur J Pharmacol 2002; 444:39-45. [PMID: 12191580 DOI: 10.1016/s0014-2999(02)01608-4] [Citation(s) in RCA: 264] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Pteropodine and isopteropodine are heteroyohimbine-type oxindole alkaloid components of Uncaria tomentosa (Willd.) DC, a Peruvian medicinal plant known as cat's claw. In this study, the effects of these alkaloids on the function of Ca(2+)-activated Cl(-) currents evoked by stimulation of G protein-coupled muscarinic M(1) acetylcholine and 5-HT(2) receptors were studied in Xenopus oocytes in which rat cortex total RNA was translated. Pteropodine and isopteropodine (1-30 microM) failed to induce membrane current by themselves. However, these alkaloids markedly enhanced the current responses evoked by both acetylcholine and 5-hydroxyhyptamine (5-HT) in a concentration-dependent and reversible manner with the maximal effects at 30 microM. Pteropodine and isopteropodine produced 2.7- and 3.3-fold increases in the acetylcholine response with EC(50) values of 9.52 and 9.92 microM, respectively, and 2.4- and 2.5-fold increases in the 5-HT response with EC(50) values of 13.5 and 14.5 microM, respectively. In contrast, in oocytes injected with total RNA from the rat cerebellum or spinal cord, neither alkaloid had an effect on the metabotropic current responses mediated by glutamate receptor(1 and 5) (mGlu(1/5)) receptors or ionotropic responses mediated by N-methyl-D-aspartate, kainic acid or glycine. Pteropodine and isopteropodine (10 microM) significantly reduced the EC(50) values of acetylcholine and 5-HT that elicited current responses, but had no effect on the maximal current responses elicited by acetylcholine and 5-HT. On the other hand, mitraphylline, a stereoisomer of pteropodine, failed to modulate acetylcholine- and 5-HT-induced responses. These results suggest that pteropodine and isopteropodine act as positive modulators of muscarinic M(1) and 5-HT(2) receptors.
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Affiliation(s)
- Tai-Hyun Kang
- Department of Pharmacology, Institute of Natural Medicine, Toyama Medical and Pharmaceutical University, 2630 Sugitani, Toyama, 930-0194, Japan
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