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Seck I, Ndoye SF, Kapchoup MVK, Nguemo F, Ciss I, Ba LA, Ba A, Sokhna S, Seck M. Effects of plant extracts and derivatives on cardiac K +, Nav, and Ca v channels: a review. Nat Prod Res 2024:1-28. [PMID: 38586947 DOI: 10.1080/14786419.2024.2337112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 03/24/2024] [Indexed: 04/09/2024]
Abstract
Natural products (NPs) are endless sources of compounds for fighting against several pathologies. Many dysfunctions, including cardiovascular disorders, such as cardiac arrhythmias have their modes of action regulation of the concentration of electrolytes inside and outside the cell targeting ion channels. Here, we highlight plant extracts and secondary metabolites' effects on the treatment of related cardiac pathologies on hERG, Nav, and Cav of cardiomyocytes. The natural product's pharmacology of expressed receptors like alpha-adrenergic receptors causes an influx of Ca2+ ions through receptor-operated Ca2+ ion channels. We also examine the NPs associated with cardiac contractions such as myocardial contractility by reducing the L-type calcium current and decreasing the intracellular calcium transient, inhibiting the K+ induced contractions, decreasing amplitude of myocyte shortening and showed negative ionotropic and chronotropic effects due to decreasing cytosolic Ca2+. We examine whether the NPs block potassium channels, particular the hERG channel and regulatory effects on Nav1.7.
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Affiliation(s)
- Insa Seck
- Laboratoire de Chimie de Coordination Organique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
- Laboratoire de Chimie Organique et Thérapeutique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | - Samba Fama Ndoye
- Laboratoire de Chimie Organique et Thérapeutique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | | | - Filomain Nguemo
- Institute of Neurophysiology, University of Cologne, Cologne, Germany
| | - Ismaila Ciss
- Laboratoire de Chimie Organique et Thérapeutique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | - Lalla Aicha Ba
- Laboratoire de Chimie Organique et Thérapeutique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | - Abda Ba
- Laboratoire de Chimie Organique et Thérapeutique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | - Seynabou Sokhna
- Laboratoire de Chimie Organique et Thérapeutique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | - Matar Seck
- Laboratoire de Chimie Organique et Thérapeutique, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
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Hu M, Xu M, Chen Y, Ye Z, Zhu S, Cai J, Zhang M, Zhang C, Huang R, Ye Q, Ao H. Therapeutic potential of toosendanin: Novel applications of an old ascaris repellent as a drug candidate. Biomed Pharmacother 2023; 167:115541. [PMID: 37738795 DOI: 10.1016/j.biopha.2023.115541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 09/13/2023] [Accepted: 09/17/2023] [Indexed: 09/24/2023] Open
Abstract
Toosendanin (TSN), extracted from Melia. toosendan Sieb.et Zucc. and Melia. azedarach L., has been developed into an ascaris repellent in China. However, with the improvement of public health protection, the incidence of ascariasis has been reduced considerably, resulting in limited medical application of TSN. Therefore, it is questionable whether this old ascaris repellent can develop into a drug candidate. Modern studies have shown that TSN has strong pharmacological activities, including anti-tumor, anti-botulinum, anti-viral and anti-parasitic potentials. It also can regulate fat formation and improve inflammation. These researches indicate that TSN has great potential to be developed into a corresponding medical product. In order to better development and application of TSN, the availability, pharmacodynamics, pharmacokinetics and toxicology of TSN are summarized systematically. In addition, this review discusses shortcomings in the current researches and provides useful suggestions about how TSN developed into a drug candidate. Therefore, this paper illustrates the possibility of developing TSN as a medical product, aimed to provide directions for the clinical application and further research of TSN.
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Affiliation(s)
- Minghao Hu
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China; School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China
| | - Min Xu
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China
| | - Yuchen Chen
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China; School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China
| | - Zhangkai Ye
- Xinjiang Normal University, Urumqi 830017, Xinjiang, China
| | - Shunpeng Zhu
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China; School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China
| | - Jia Cai
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China; School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China
| | - Mengxue Zhang
- First School of Clinical Medicine, Beijing University of Chinese Medicine, Beijing 100029, China
| | - Chi Zhang
- School of health and Rehabilitation, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China
| | - Ruizhen Huang
- Affiliated Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu 610072, China.
| | - Qiang Ye
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China; School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China.
| | - Hui Ao
- State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China; Innovative Institute of Chinese Medicine and Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, Sichuan, China.
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3
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Shen C, Pan Z, Wu X, Zhong C, Li Q, Si Y, Liu C, Tu H, Deng Z, Zhu Z, Guo J, Xin X, Liu M. A Sensitive Liquid Chromatography-Mass Spectrometry Method for Determination of Toosendanin in Rat Plasma and its Application to Pharmacokinetic Study. J Chromatogr Sci 2021; 60:478-485. [PMID: 34929736 DOI: 10.1093/chromsci/bmab135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Indexed: 11/13/2022]
Abstract
A simple, rapid and sensitive analytical method was developed for the determination of toosendanin in rat plasma using liquid chromatography tandem mass spectrometry (LC-MS/MS). Andrographolide was selected as the internal standard, and the plasma samples were extracted by liquid-liquid extraction with diethyl ether. Chromatographic separation was performed on a Dikma Spursil C18, 3.5 μm (150 × 2.1 mm i.d) analytical column with 85% methanol:water (v/v) containing 0.025% formic acid (pH = 3.9) as mobile phase. The flow rate was 0.25 mL/min, and the total run time was 3 min. Detection was performed with a triple-quadrupole tandem mass spectrometer using negative ion mode electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. The MS/MS ion transitions monitored were m/z 573.1 → 531.1 and 349.0 → 287.0 for toosendanin and andrographolide, respectively. Good linearity was observed over the concentration range of 3.125-500 ng/mL in 100 μL of rat plasma with a correlation coefficient ˃0.9997. Intra- and inter-assay variabilities were ˂8.5% in plasma. The recovery and the matrix effect were in the range 71.8-73.5% and 96.4-103.8%, respectively. The analyte was stable under various conditions (at room temperature, during freeze-thaw settings, in the autosampler, and under deep-freeze conditions). The method was successfully applied to a pharmacokinetic study of toosendanin after its oral administration in rats at a dose of 10 mg/kg.
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Affiliation(s)
- Chuangpeng Shen
- Xinjiang Medical University, Xinjiang Uygur Autonomous Region, Urumqi 830011, China.,Department of Endocrinology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, China.,Department of Chinese Medicine, The First People's Hospital of Kashgar Prefecture, Xinjiang Uygur Autonomous Region, Kashgar 844000, China
| | - Zhisen Pan
- The First Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Xiaojie Wu
- Central Lab, Binzhou People's Hospital, Binzhou 256600, China
| | - Chong Zhong
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Qiao Li
- Department of Endocrinology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Yuqi Si
- The First Clinical Medical College of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Changhui Liu
- School of Chinese Material Medical, Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Haitao Tu
- Department of Nephrology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Zhijun Deng
- Department of Science and Education, Guangzhou Hospital of Traditional Chinese Medicine, Guangzhou 510130, China
| | - Zhangzhi Zhu
- Department of Endocrinology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
| | - Jiewen Guo
- Department of Science and Education, Guangzhou Hospital of Traditional Chinese Medicine, Guangzhou 510130, China
| | - Xiaoyi Xin
- Department of Chinese Medicine, The First Affiliated Hospital of Xinjiang Medical University, Xinjiang Uygur Autonomous Region, Urumqi 830011, China
| | - Min Liu
- Department of Endocrinology, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510405, China
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Slater LH, Hett EC, Mark K, Chumbler NM, Patel D, Lacy DB, Collier RJ, Hung DT. Identification of novel host-targeted compounds that protect from anthrax lethal toxin-induced cell death. ACS Chem Biol 2013; 8:812-22. [PMID: 23343607 DOI: 10.1021/cb300555n] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Studying how pathogens subvert the host to cause disease has contributed to the understanding of fundamental cell biology. Bacillus anthracis, the causative agent of anthrax, produces the virulence factor lethal toxin to disarm host immunity and cause pathology. We conducted a phenotypic small molecule screen to identify inhibitors of lethal toxin-induced macrophage cell death and used an ordered series of secondary assays to characterize the hits and determine their effects on cellular function. We identified a structurally diverse set of small molecules that act at various points along the lethal toxin pathway, including inhibitors of endocytosis, natural product inhibitors of organelle acidification (e.g., the botulinum neurotoxin inhibitor, toosendanin), and a novel proteasome inhibitor, 4MNB (4-methoxy-2-[2-(5-methoxy-2-nitrosophenyl)ethyl]-1-nitrosobenzene). Many of the compounds, including three drugs approved for use in humans, also protected against the related Clostridium difficile toxin TcdB, further demonstrating their value as novel tools for perturbation and study of toxin biology and host cellular processes and highlighting potential new strategies for intervening on toxin-mediated diseases.
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Affiliation(s)
- Louise H. Slater
- Department of Molecular Biology
and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street,
Boston, Massachusetts 02114, United States
- Infectious Disease Initiative, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts
02142, United States
- Department
of Microbiology and
Immunobiology, Harvard Medical School,
77 Ave. Louis Pasteur Boston, Massachusetts 02115, United States
| | - Erik C. Hett
- Department of Molecular Biology
and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street,
Boston, Massachusetts 02114, United States
- Infectious Disease Initiative, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts
02142, United States
- Department
of Microbiology and
Immunobiology, Harvard Medical School,
77 Ave. Louis Pasteur Boston, Massachusetts 02115, United States
| | - Kevin Mark
- Department of Molecular Biology
and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street,
Boston, Massachusetts 02114, United States
- Infectious Disease Initiative, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts
02142, United States
- Department
of Microbiology and
Immunobiology, Harvard Medical School,
77 Ave. Louis Pasteur Boston, Massachusetts 02115, United States
| | - Nicole M. Chumbler
- Department of Microbiology and
Immunology, Vanderbilt University Medical Center, A-5301 Medical Center North, 1161 21st Avenue South, Nashville,
Tennessee 37232, United States
| | - Deepa Patel
- Department
of Microbiology and
Immunobiology, Harvard Medical School,
77 Ave. Louis Pasteur Boston, Massachusetts 02115, United States
| | - D. Borden Lacy
- Department of Microbiology and
Immunology, Vanderbilt University Medical Center, A-5301 Medical Center North, 1161 21st Avenue South, Nashville,
Tennessee 37232, United States
| | - R. John Collier
- Department
of Microbiology and
Immunobiology, Harvard Medical School,
77 Ave. Louis Pasteur Boston, Massachusetts 02115, United States
| | - Deborah T. Hung
- Department of Molecular Biology
and Center for Computational and Integrative Biology, Massachusetts General Hospital, 185 Cambridge Street,
Boston, Massachusetts 02114, United States
- Infectious Disease Initiative, Broad Institute, 7 Cambridge Center, Cambridge, Massachusetts
02142, United States
- Department
of Microbiology and
Immunobiology, Harvard Medical School,
77 Ave. Louis Pasteur Boston, Massachusetts 02115, United States
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5
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Affiliation(s)
- Qin-Gang Tan
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P.R.China
- Guilin Medical University, Guilin, 541004, P.R.China
| | - Xiao-Dong Luo
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, P.R.China
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6
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Willis B, Eubanks LM, Dickerson TJ, Janda KD. The strange case of the botulinum neurotoxin: using chemistry and biology to modulate the most deadly poison. Angew Chem Int Ed Engl 2008; 47:8360-79. [PMID: 18844202 DOI: 10.1002/anie.200705531] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the classic novella "The Strange Case of Dr. Jekyll and Mr. Hyde", Robert Louis Stevenson paints a stark picture of the duality of good and evil within a single man. Botulinum neurotoxin (BoNT), the most potent known toxin, possesses an analogous dichotomous nature: It shows a pronounced morbidity and mortality, but it is used with great effect in much lower doses in a wide range of clinical scenarios. Recently, tremendous strides have been made in the basic understanding of the structure and function of BoNT, which have translated into widespread efforts towards the discovery of biomacromolecules and small molecules that specifically modulate BoNT activity. Particular emphasis has been placed on the identification of inhibitors that can counteract BoNT exposure in the event of a bioterrorist attack. This Review summarizes the current advances in the development of therapeutics, including vaccines, peptides, and small-molecule inhibitors, for the prevention and treatment of botulism.
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Affiliation(s)
- Bert Willis
- Department of Chemistry, Skaggs Institute for Chemical Biology, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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7
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Willis B, Eubanks L, Dickerson T, Janda K. Der seltsame Fall des Botulinum-Neurotoxins: chemische und biologische Modulierung des tödlichsten aller Gifte. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200705531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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8
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Shi YL, Li MF. Biological effects of toosendanin, a triterpenoid extracted from Chinese traditional medicine. Prog Neurobiol 2007; 82:1-10. [PMID: 17363132 DOI: 10.1016/j.pneurobio.2007.02.002] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2006] [Revised: 11/27/2006] [Accepted: 02/06/2007] [Indexed: 11/21/2022]
Abstract
Toosendanin (TSN) is a triterpenoid extracted from Melia toosendan Sieb et Zucc, which was used as a digestive tract-parasiticide and agricultural insecticide in ancient China. TSN was demonstrated to be a selective presynaptic blocker and an effective antibotulismic agent. By interfering with neurotransmitter release through an initial facilitation followed by a subsequent depression, TSN eventually blocks synaptic transmission at both the neuro-muscular junction and central synapses. Despite sharing some similar actions with botulinum neurotoxin (BoNT), TSN has a marked antibotulismic effect in vivo and in vitro. Studies suggest that the antibotulismic effect of TSN is achieved by preventing BoNT from approaching its enzymatic substrate, the SNARE protein. It is also found that TSN can induce differentiation and apoptosis in several cell lines, and suppress proliferation of various human cancer cells. TSN inhibits various K(+)-channels, selectively facilitates Ca(2+)-influx via L-type Ca(2+) channels and increases intracellular Ca(2+) concentration ([Ca(2+)](i)). The TSN-induced [Ca(2+)](i) increase and overload could be responsible for the TSN-induced biphasic effect on transmitter release, cell differentiation, apoptosis as well as the cytoxicity of TSN.
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Affiliation(s)
- Yu-Liang Shi
- Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, PR China.
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9
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Dickerson TJ, Janda KD. The use of small molecules to investigate molecular mechanisms and therapeutic targets for treatment of botulinum neurotoxin A intoxication. ACS Chem Biol 2006; 1:359-69. [PMID: 17163773 DOI: 10.1021/cb600179d] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Botulinum neurotoxins (BoNTs) are agents responsible for botulism, a disease characterized by peripheral neuromuscular blockade and subsequent flaccid paralysis. The potent paralytic ability of these toxins has resulted in their use as a therapeutic; however, BoNTs are also classified by the Centers for Disease Control and Prevention as one of the six highest-risk threat agents of bioterrorism. Consequently, a thorough understanding of the molecular mechanism of BoNT toxicity is crucial before effective inhibitors and, ultimately, an approved drug can be developed. In this article, we systematically detail BoNT intoxication by examining each of the discrete steps in this process. Additionally, rationally designed strategies for combating the toxicity of the most potent BoNT serotype are evaluated.
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Affiliation(s)
- Tobin J Dickerson
- Departments of Chemistry and Immunology, The Skaggs Institute for Chemical Biology, and Worm Institute for Research and Medicine (WIRM), The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
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10
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Abstract
Background Recent work has indicated an increasingly complex role for astrocytes in the central nervous system. Astrocytes are now known to exchange information with neurons at synaptic junctions and to alter the information processing capabilities of the neurons. As an extension of this trend a hypothesis was proposed that astrocytes function to store information. To explore this idea the ion channels in biological membranes were compared to models known as cellular automata. These comparisons were made to test the hypothesis that ion channels in the membranes of astrocytes form a dynamic information storage device. Results Two dimensional cellular automata were found to behave similarly to ion channels in a membrane when they function at the boundary between order and chaos. The length of time information is stored in this class of cellular automata is exponentially related to the number of units. Therefore the length of time biological ion channels store information was plotted versus the estimated number of ion channels in the tissue. This analysis indicates that there is an exponential relationship between memory and the number of ion channels. Extrapolation of this relationship to the estimated number of ion channels in the astrocytes of a human brain indicates that memory can be stored in this system for an entire life span. Interestingly, this information is not affixed to any physical structure, but is stored as an organization of the activity of the ion channels. Further analysis of two dimensional cellular automata also demonstrates that these systems have both associative and temporal memory capabilities. Conclusion It is concluded that astrocytes may serve as a dynamic information sink for neurons. The memory in the astrocytes is stored by organizing the activity of ion channels and is not associated with a physical location such as a synapse. In order for this form of memory to be of significant duration it is necessary that the ion channels in the astrocyte syncytium be electrically in contact with each other. This function may be served by astrocyte gap junctions and suggests that agents that selectively block these gap junctions should disrupt memory.
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Affiliation(s)
- Robert M Caudle
- Department of Oral and Maxillofacial Surgery and Diagnostic Sciences, University of Florida College of Dentistry, Gainesville, Florida 32610, USA.
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11
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Li MF, Shi YL. Toosendanin interferes with pore formation of botulinum toxin type A in PC12 cell membrane. Acta Pharmacol Sin 2006; 27:66-70. [PMID: 16364212 DOI: 10.1111/j.1745-7254.2006.00236.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
AIM Botulinum neurotoxins (BoNT) abort the process of neurotransmitter release at presynaptic motor nerve terminals, causing muscle paralysis. The ability of botulinum toxin to produce its effect is dependent on the ability of the light chain to cleave the SNARE proteins associated with transmitter release. Translocation of the light chain protease through the heavy chain-formed channel is a pivotal step in the intoxication process. Toosendanin (TSN), a triterpenoid derivative extracted from a Chinese traditional medicine, has been demonstrated to be an effective cure for experimental botulism. This study was designed to explore the antibotulismic mechanisms of toosendanin. METHODS The inside-out single-channel recording patch-clamp technique was used to record the BoNT/A-induced currents in the presence and absence of TSN. RESULTS Channel formation was delayed and the sizes of the channels were reduced in the TSN-treated PC12 cell membrane. CONCLUSION The antibotulismic effect of TSN might occur via interference with toxin translocation.
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Affiliation(s)
- Mu-feng Li
- Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai
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12
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Li MF, Shi YL. The long-term effect of toosendanin on current through nifedipine-sensitive Ca2+ channels in NG108-15 cells. Toxicon 2005; 45:53-60. [PMID: 15581683 DOI: 10.1016/j.toxicon.2004.09.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2004] [Accepted: 09/16/2004] [Indexed: 11/17/2022]
Abstract
Toosendanin is a triterpenoid derivative extracted from Melia toosendan Sieb et Zucc. Previous studies demonstrated that toosendanin could block neurotransmission and stimulate PC12 cell into differentiation and apoptosis. These actions of toosendanin were suggested to result from a continuous increase in Ca2+ influx, which led to intracellular Ca2+ overload. Here, we observed the long-term effect of toosendanin on Ca2+ channels in NG108-15 cells by whole-cell patch-clamp recording. Obtained data showed that a prolonged exposure to toosendanin induced a continuous increase in the Ca2+ influx in a concentration and time-dependent manner while a brief treatment induced an irreversible increase in Ca2+ influx in differentiated NG108-15 cells. The nifedipine-sensitive L-type currents were significantly increased after exposure to TSN while the nifedipine-resistant or omega-conotoxin MVIIC-sensitive currents were not affected.
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Affiliation(s)
- Mu-Feng Li
- Key Laboratory of Neurobiology, Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, People's Republic of China
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13
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Li MF, Shi YL. Toosendanin, a triterpenoid derivative, acts as a novel agonist of L-type Ca2+ channels in neonatal rat ventricular cells. Eur J Pharmacol 2004; 501:71-8. [PMID: 15464064 DOI: 10.1016/j.ejphar.2004.08.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2004] [Revised: 08/05/2004] [Accepted: 08/10/2004] [Indexed: 10/26/2022]
Abstract
Toosendanin, a triterpenoid derivative extracted from Melia toosendan Sieb et Zucc, was demonstrated to be potentially useful in medical and scientific researches. Here, we investigated the effects of toosendanin on L-type voltage-dependent Ca(2+) channels in cultured neonatal rat ventricular cells, using whole-cell patch-clamp method. Toosendanin irreversibly increased L-type Ca(2+) current (I(Ca(L))) in a concentration-dependent manner and shifted the maximum of the current/voltage relationship from 8.3+/-3.7 to 1.7+/-3.7 mV, without modifying the threshold potential of the current. Toosendanin shifted the steady-state activation and inactivation curves to the left. The deactivation kinetics of the I(Ca(L)) was significantly slowed by toosendanin while the activation kinetics was not affected. The cells pretreated with 100 nM 1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)phenyl]-3-pyridinecarboxylic acid methyl ester (S(-)-BayK8644) still respond to further addition of 87 microM toosendanin, and vice versa. These results prove toosendanin to be a novel L-type Ca(2+) channel agonist, which possesses a distinct binding site from BayK8644.
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Affiliation(s)
- Mu-Feng Li
- Key Laboratory of Neurobiology, Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, P.R. China
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14
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Li MF, Wu Y, Wang ZF, Shi YL. Toosendanin, a triterpenoid derivative, increases Ca2+ current in NG108-15 cells via L-type channels. Neurosci Res 2004; 49:197-203. [PMID: 15140562 DOI: 10.1016/j.neures.2004.02.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2003] [Accepted: 02/23/2004] [Indexed: 11/25/2022]
Abstract
Toosendanin, a triterpenoid derivative extracted from Melia toosendan Sieb et Zucc, was demonstrated to be a selective presynaptic blocker and an effective antibotulismic agent in previous studies. Here, we observed its effects on Ca(2+) channels in NG108-15 cells by whole-cell patch-clamp recording. Obtained data showed that toosendanin concentration dependently increased the high-voltage-activated (HVA) Ca(2+) current with an EC(50) of 5.13 microM in differentiated NG108-15 cells. The enhancement effect was still observed when the cells were pretreated with 5 microM omega-conotoxin MVIIC. However, when the cells were preincubated with 5 microM nifedipine or 10 microM verapamil-containing solution, the effect was absent. In undifferentiated NG108-15 cells, which only express T-type Ca(2+) channels, toosendanin did not affect Ca(2+) currents. These results show that toosendanin increases Ca(2+) influx in NG108-15 cells via L-type Ca(2+) channels.
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Affiliation(s)
- Mu-Feng Li
- Key Laboratory of Neurobiology, Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, PR China
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15
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Zhou JY, Wang ZF, Ren XM, Tang MZ, Shi YL. Antagonism of botulinum toxin type A-induced cleavage of SNAP-25 in rat cerebral synaptosome by toosendanin. FEBS Lett 2003; 555:375-9. [PMID: 14644446 DOI: 10.1016/s0014-5793(03)01291-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Toosendanin (TSN), a triterpenoid derivative extracted from Chinese traditional medicine, has been demonstrated to be an effective cure for experimental botulism. This study is designed to explore its antibotulismic mechanism by Western blotting. The results showed that TSN incubation did not change the electrophoresis pattern and the amounts of synaptosomal-associated protein of 25 kDa (SNAP-25), syntaxin and synaptobrevin/vesicle-associated membrane protein in rat cerebral synaptosomes, but made the synaptosomes completely resistant to botulinum neurotoxin A (BoNT/A)-mediated cleavage of SNAP-25. After binding of BoNT/A to synaptosomes, TSN still partially antagonized the toxin-mediated cleavage of SNAP-25. However, TSN-incubated synaptosomal membrane fraction did not resist the cleavage of SNAP-25 by the light chain of BoNT/A. It is suggested that the antibotulismic effect of TSN results from blocking the toxin's approach to its enzymatic substrate.
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Affiliation(s)
- Jian-Ying Zhou
- Key Laboratory of Neurobiology, Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, PR China
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Tang MZ, Wang ZF, Shi YL. Toosendanin induces outgrowth of neuronal processes and apoptosis in PC12 cells. Neurosci Res 2003; 45:225-31. [PMID: 12573469 DOI: 10.1016/s0168-0102(02)00225-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In the present study, the effects of toosendanin on cell differentiation and apoptosis were investigated in PC12 cells. The results showed that after 24-48 h of culture in a medium containing toosendanin (approximately 1-10x10(-7) M), cell differentiation and outgrowth of neuronal processes were promoted. Combined treatment with toosendanin and a calcium channel blocker, nifedipine or omega-conotoxin GVIA, resulted in a significant inhibition of the toosendanin-induced effects. Pretreatment of PC12 cells with BAPTA-AM also inhibited the toosendanin-induced effects; however, these effects were not inhibited by pertussis toxin and H-7 in the medium. Toosendanin also induced cell apoptosis. Based on the DNA content determined by flow cytometric analysis, the number of apoptotic cells significantly increased when the incubation time in the toosendanin-containing medium was lasted up to 72 h. Toosendanin at a higher concentration (> or =1 x 10(-6) M) caused cell death while it had no effect on cell division at concentrations lower than 1 x 10(-7) M.
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Affiliation(s)
- Mian-Zhi Tang
- Key Laboratory of Neurobiology, Institute of Physiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, PR China
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Abstract
AIM Toosendanin is a pre-synaptic blocker at the neuromuscular junction and its inhibitory effect is divided into an initial facilitative/stimulatory phase followed by a prolonged inhibitory phase. The present study investigated whether the subsequent inhibitory phase was due to exhaustion of the secretory machinery as a result of extensive stimulation during the initial facilitative phase. More specifically, this paper examined whether toosendanin could directly inhibit the secretory machinery in exocrine cells. METHODS Rat pancreatic acinar cells were isolated by collagenase digestion. Secretion was assessed by measuring the amount of amylase released into the extracellular medium as a percentage of the total present in the cells before stimulation. Cholecystokinin (CCK)-induced increases in intracellular calcium in single cells were measured with fura-2 microfluorometry. RESULTS Effects of toosendanin on CCK-induced amylase secretion and calcium oscillations were investigated. Toosendanin of 87-870 microM had no effect on 10 pM-100 nM CCK-stimulated amylase secretion, nor did 8.7-870 microM toosendanin inhibit 5 pM CCK-induced calcium oscillations. In contrast, 10 nM CCK(1) receptor antagonist FK 480 completely blocked 5 pM CCK-induced calcium oscillations. CONCLUSION The pre-synaptic "blocker" toosendanin is a selective activator of the voltage-dependent calcium channels, but does not interfere with the secretory machinery itself.
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Affiliation(s)
- Zong-Jie Cui
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China.
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