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Rivera-García LG, Francis-Malavé AM, Castillo ZW, Uong CD, Wilson TD, Ferchmin PA, Eterovic V, Burton MD, Carrasquillo Y. Anti-hyperalgesic and anti-inflammatory effects of 4R-tobacco cembranoid in a mouse model of inflammatory pain. J Inflamm (Lond) 2024; 21:2. [PMID: 38267952 PMCID: PMC10809744 DOI: 10.1186/s12950-023-00373-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 12/21/2023] [Indexed: 01/26/2024] Open
Abstract
4R is a tobacco cembranoid that binds to and modulates cholinergic receptors and exhibits neuroprotective and anti-inflammatory activity. Given the established function of the cholinergic system in pain and inflammation, we propose that 4R is also analgesic. Here, we tested the hypothesis that systemic 4R treatment decreases pain-related behaviors and peripheral inflammation via modulation of the alpha 7 nicotinic acetylcholine receptors (α7 nAChRs) in a mouse model of inflammatory pain. We elicited inflammation by injecting Complete Freund's Adjuvant (CFA) into the hind paw of male and female mice. We then assessed inflammation-induced hypersensitivity to cold, heat, and tactile stimulation using the Acetone, Hargreaves, and von Frey tests, respectively, before and at different time points (2.5 h - 8d) after a single systemic 4R (or vehicle) administration. We evaluated the contribution of α7 nAChRs 4R-mediated analgesia by pre-treating mice with a selective antagonist of α7 nAChRs followed by 4R (or vehicle) administration prior to behavioral tests. We assessed CFA-induced paw edema and inflammation by measuring paw thickness and quantifying immune cell infiltration in the injected hind paw using hematoxylin and eosin staining. Lastly, we performed immunohistochemical and flow cytometric analyses of paw skin in α7 nAChR-cre::Ai9 mice to measure the expression of α7 nAChRs on immune subsets. Our experiments show that systemic administration of 4R decreases inflammation-induced peripheral hypersensitivity in male and female mice and inflammation-induced paw edema in male but not female mice. Notably, 4R-mediated analgesia and anti-inflammatory effects lasted up to 8d after a single systemic administration on day 1. Pretreatment with an α7 nAChR-selective antagonist prevented 4R-mediated analgesia and anti-inflammatory effects, demonstrating that 4R effects are via modulation of α7 nAChRs. We further show that a subset of immune cells in the hind paw expresses α7 nAChRs. However, the number of α7 nAChR-expressing immune cells is unaltered by CFA or 4R treatment, suggesting that 4R effects are independent of α7 nAChR-expressing immune cells. Together, our findings identify a novel function of the 4R tobacco cembranoid as an analgesic agent in both male and female mice that reduces peripheral inflammation in a sex-dependent manner, further supporting the pharmacological targeting of the cholinergic system for pain treatment.
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Affiliation(s)
- Luis G Rivera-García
- Division of Intramural Research National Center for Complementary and Integrative Health, 35 Convent Drive, Building 35A / Room 1E-410, Bethesda, MD, 20892, USA
- Department of Neuroscience, Universidad Central Del Caribe School of Medicine, Bayamon, Puerto Rico, USA
| | - Adela M Francis-Malavé
- Division of Intramural Research National Center for Complementary and Integrative Health, 35 Convent Drive, Building 35A / Room 1E-410, Bethesda, MD, 20892, USA
| | - Zachary W Castillo
- Neuroimmunology and Behavior Group, Department of Neuroscience, Center for Advanced Pain Studies (CAPS), School of Behavioral and Brain Sciences, University of Texas, Dallas, USA
| | - Calvin D Uong
- Neuroimmunology and Behavior Group, Department of Neuroscience, Center for Advanced Pain Studies (CAPS), School of Behavioral and Brain Sciences, University of Texas, Dallas, USA
| | - Torri D Wilson
- Division of Intramural Research National Center for Complementary and Integrative Health, 35 Convent Drive, Building 35A / Room 1E-410, Bethesda, MD, 20892, USA
| | - P A Ferchmin
- Department of Neuroscience, Universidad Central Del Caribe School of Medicine, Bayamon, Puerto Rico, USA
| | - Vesna Eterovic
- Department of Neuroscience, Universidad Central Del Caribe School of Medicine, Bayamon, Puerto Rico, USA
| | - Michael D Burton
- Neuroimmunology and Behavior Group, Department of Neuroscience, Center for Advanced Pain Studies (CAPS), School of Behavioral and Brain Sciences, University of Texas, Dallas, USA
| | - Yarimar Carrasquillo
- Division of Intramural Research National Center for Complementary and Integrative Health, 35 Convent Drive, Building 35A / Room 1E-410, Bethesda, MD, 20892, USA.
- National Institute On Drug Abuse, National Institutes of Health, 35 Convent Drive, Building 35A / Room 1E-410, Bethesda, MD, 20892, USA.
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Nicotiana tabacum Leaf Waste: Morphological Characterization and Chemical-Functional Analysis of Extracts Obtained from Powder Leaves by Using Green Solvents. Molecules 2023; 28:molecules28031396. [PMID: 36771071 PMCID: PMC9920059 DOI: 10.3390/molecules28031396] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/19/2023] [Accepted: 01/26/2023] [Indexed: 02/05/2023] Open
Abstract
Tobacco cultivation and industrialization are characterized by the production of trillions of pre-harvest and post-harvest waste biomasses each year with the resulting negative effects on the environment. The leaves of blunt, pre-harvest waste, could be further used to obtain bioactive metabolites, i.e., polyphenols and alkaloids, for its potential cosmetic use. This study was conducted to obtain bio-compounds from pre-harvest tobacco leaf waste (var. Virginia) by applying conventional and green solvents (NaDES). Leaves and ground leaf waste were characterized based on their microscopic features. Conventional solvents, such as water, acetone, ethanol, and non-conventional solvents, such as Natural Deep Eutectic Solvents (NaDES), i.e., sucrose:lactic acid (LAS), frutose:glucose:sucrose (FGS), lactic acid:sucrose:water (SALA), choline chloride:urea (CU), and citric acid: propylene glycol (CAP) were used for bioactive extraction from tobacco waste powder. CU, FGS, and acetone/ethanol had similar behavior for the best extraction of alkaloids (6.37-11.23 mg ACE/g tobacco powder). LAS, FGS, SALA, and CU were more effective in phenolic compound extraction than conventional solvents (18.13-21.98 mg AGE/g tobacco powder). Because of this, LAS and SALA could be used to obtain phenolic-enriched extracts with lower alkaloid content rather than CU and FGS. Extracts of the powder obtained with conventional solvent or CU showed a high level of sugars (47 mg/g tobacco powder) The ABTS antioxidant capacity of tobacco leaf powder was higher in the extracts obtained with CU, FGS, and acetone (SC50 1.6-5 µg GAE/mL) while H2O2 scavenging activity was better in the extracts obtained with LAS, CAP and SALA (SC50 3.8-8.7 µg GAE/mL). Due to the biocompatibility of the NaDES with the components of tobacco leaf waste, the opportunity to apply these extracts directly in antioxidant formulations, such as cosmetics, phytotherapic, and other formulations of topic use seems promising. Furthermore, NaDES constituents, i.e., urea and organic acid can also have beneficial effects on the skin.
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Hong SW, Teesdale-Spittle P, Page R, Ellenbroek B, Truman P. Biologically Active Compounds Present in Tobacco Smoke: Potential Interactions Between Smoking and Mental Health. Front Neurosci 2022; 16:885489. [PMID: 35557609 PMCID: PMC9087043 DOI: 10.3389/fnins.2022.885489] [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: 02/28/2022] [Accepted: 03/28/2022] [Indexed: 12/01/2022] Open
Abstract
Tobacco dependence remains one of the major preventable causes of premature morbidity and mortality worldwide. There are well over 8,000 compounds present in tobacco and tobacco smoke, but we do not know what effect, if any, many of them have on smokers. Major interest has been on nicotine, as well as on toxic and carcinogenic effects and several major and minor components of tobacco smoke responsible for the negative health effects of smoking have been elucidated. Smokers themselves report a variety of positive effects from smoking, including effects on depression, anxiety and mental acuity. Smoking has also been shown to have protective effects in Parkinson’s Disease. Are the subjective reports of a positive effect of smoking due to nicotine, of some other components of tobacco smoke, or are they a manifestation of the relief from nicotine withdrawal symptoms that smoking provides? This mini-review summarises what is currently known about the components of tobacco smoke with potential to have positive effects on smokers.
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Affiliation(s)
- Sa Weon Hong
- School of Health Sciences, Massey University, Wellington, New Zealand
| | - Paul Teesdale-Spittle
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Rachel Page
- School of Health Sciences, Massey University, Wellington, New Zealand
| | - Bart Ellenbroek
- Department of Psychology, Victoria University of Wellington, Wellington, New Zealand
| | - Penelope Truman
- School of Health Sciences, Massey University, Wellington, New Zealand
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Xu K, Du X, Ren X, Li X, Li H, Fu X, Wei X. Structural Modifications and Biological Activities of Natural α- and β-Cembrenediol: A Comprehensive Review. Pharmaceuticals (Basel) 2022; 15:ph15050601. [PMID: 35631427 PMCID: PMC9143853 DOI: 10.3390/ph15050601] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 05/10/2022] [Accepted: 05/10/2022] [Indexed: 02/04/2023] Open
Abstract
As one of the most characteristic ingredients of glandular trichome secretions from Nicotiana tabacum L. (tobacco), natural cembrenediols, namely, (1S,2E,4S,6R,7E,11E)-2,7,11-cembratriene-4,6-diol (α-cembrenediol/α-CBD) and its C-4 epimer (β-cembrenediol/β-CBD), have attracted considerable attention for their potent antitumor, neuroprotective, antimicrobial, and other activities. Many researchers are committed to exploring the possibility of utilizing these two cembrenediols and their derivatives both in human medicine and in agricultural fungicides. To the best of our knowledge, this review is the first to provide a comprehensive summary of the chemical modifications and bioactivities of α- and β-CBD from their discovery to the present day; the review highlights their potential medicinal value for humans. The extensive references from 1962 to 2022 provided herein were systematically gathered from the SciFinder, Web of Science, and Google Scholar databases. We expect this review to assist in providing practical ideas for future drug development based on α- and β-CBD and in further facilitating the utilization of the tobacco cembrenediols.
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Affiliation(s)
- Kuo Xu
- Shandong University of Traditional Chinese Medicine, Jinan 250355, China; (K.X.); (X.D.); (X.R.); (X.L.); (H.L.)
- Qingdao Academy of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Qingdao 266114, China
| | - Xinying Du
- Shandong University of Traditional Chinese Medicine, Jinan 250355, China; (K.X.); (X.D.); (X.R.); (X.L.); (H.L.)
- Qingdao Academy of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Qingdao 266114, China
| | - Xia Ren
- Shandong University of Traditional Chinese Medicine, Jinan 250355, China; (K.X.); (X.D.); (X.R.); (X.L.); (H.L.)
- Qingdao Academy of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Qingdao 266114, China
| | - XiuXue Li
- Shandong University of Traditional Chinese Medicine, Jinan 250355, China; (K.X.); (X.D.); (X.R.); (X.L.); (H.L.)
- Qingdao Academy of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Qingdao 266114, China
| | - Hui Li
- Shandong University of Traditional Chinese Medicine, Jinan 250355, China; (K.X.); (X.D.); (X.R.); (X.L.); (H.L.)
- Qingdao Academy of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Qingdao 266114, China
| | - Xianjun Fu
- Shandong University of Traditional Chinese Medicine, Jinan 250355, China; (K.X.); (X.D.); (X.R.); (X.L.); (H.L.)
- Qingdao Academy of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Qingdao 266114, China
- Correspondence: (X.F.); (X.W.)
| | - Xiaoyi Wei
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
- Correspondence: (X.F.); (X.W.)
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In Vivo Evaluation of the Acute Systemic Toxicity of (1S,2E,4R,6R,7E,11E)-Cembratriene-4,6-diol (4R) in Sprague Dawley Rats. NUTRACEUTICALS 2022; 2:60-70. [PMID: 35855209 PMCID: PMC9291268 DOI: 10.3390/nutraceuticals2020005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The tobacco cembranoid (1S,2E,4R,6R,7E,11E)-2,7,11-cembratriene-4,6-diol (4R) interacts with nicotinic acetylcholine receptors, which results in neuroprotection against organophosphate toxicity, brain ischemia, and Parkinson’s disease. The present study is a continuation of our previous research in which we applied a single dose of 4R 1 h before or 24 h after exposure to diisopropylfluorophosphate (DFP) (analog of the nerve agent sarin). The 4R dose robustly decreased neuroinflammation and neuronal death at both timepoints. Here, we investigated the toxicity of a single dose of 4R in male and female Sprague Dawley (SD) rats after a subcutaneous (s.c.) injection of 6, 24, or 98 mg/kg. Body weight was not affected by 4R during the 7-day observation period. No histopathologic changes in the organs were attributed to 4R. Minor hematological and blood composition variations were detected on Day 3 in the mid- and the high-dose males, but these were resolved by Day 8. At the area of the s.c. injection site, alopecia and dry skin were detected in both the 4R-treated males and females and in the female controls.
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Marine Origin Ligands of Nicotinic Receptors: Low Molecular Compounds, Peptides and Proteins for Fundamental Research and Practical Applications. Biomolecules 2022; 12:biom12020189. [PMID: 35204690 PMCID: PMC8961598 DOI: 10.3390/biom12020189] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/18/2022] [Accepted: 01/19/2022] [Indexed: 02/05/2023] Open
Abstract
The purpose of our review is to briefly show what different compounds of marine origin, from low molecular weight ones to peptides and proteins, offer for understanding the structure and mechanism of action of nicotinic acetylcholine receptors (nAChRs) and for finding novel drugs to combat the diseases where nAChRs may be involved. The importance of the mentioned classes of ligands has changed with time; a protein from the marine snake venom was the first excellent tool to characterize the muscle-type nAChRs from the electric ray, while at present, muscle and α7 receptors are labeled with the radioactive or fluorescent derivatives prepared from α-bungarotoxin isolated from the many-banded krait. The most sophisticated instruments to distinguish muscle from neuronal nAChRs, and especially distinct subtypes within the latter, are α-conotoxins. Such information is crucial for fundamental studies on the nAChR revealing the properties of their orthosteric and allosteric binding sites and mechanisms of the channel opening and closure. Similar data are provided by low-molecular weight compounds of marine origin, but here the main purpose is drug design. In our review we tried to show what has been obtained in the last decade when the listed classes of compounds were used in the nAChR research, applying computer modeling, synthetic analogues and receptor mutants, X-ray and electron-microscopy analyses of complexes with the nAChRs, and their models which are acetylcholine-binding proteins and heterologously-expressed ligand-binding domains.
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Saleh HA, Raafat KM, Temraz TA, Noureldin N, Breitinger HG, Breitinger U. Sarcophine and (7S, 8R)-dihydroxydeepoxysarcophine from the Red Sea soft coral Sarcophyton glaucum as in vitro and in vivo modulators of glycine receptors. Neurotoxicology 2020; 80:105-111. [PMID: 32702364 DOI: 10.1016/j.neuro.2020.07.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 07/13/2020] [Accepted: 07/14/2020] [Indexed: 01/16/2023]
Abstract
The inhibitory glycine receptor (GlyR) is a key mediator of synaptic signalling in spinal cord, brain stem, and higher centres of the central nervous system. We examined the glycinergic activity of sarcophine (SN), a marine terpenoid known for its various biological activities, and its trans-diol derivative (7S, 8R)-dihydroxy-deepoxysarcophine (DSN). SN was isolated from the Red Sea soft coral Sacrophyton glaucum, DSN was semisynthesized by hydrolysis of the epoxide ring. In cytotoxicity tests against HEK293 cells, SN and DSN had LD50 values of 29.3 ± 3.0 mM and 123.5 ± 13.0 mM, respectively. Both compounds were tested against recombinant human α1 glycine receptors in HEK293 cells using whole-cell recording techniques. Both, SN and DSN were shown for the first time to be inhibitors of recombinant glycine receptors, with KIvalues of 2.1 ± 0.3 μM for SN, and 109 ± 9 μM for DSN. Receptor inhibition was also studied in vivo in a mouse model of strychnine toxicity. Surprisingly, in mouse experiments strychnine inhibition was not augmented by either terpenoid. While DSN had no significant effect on strychnine toxicity, SN even delayed strychnine effects. This could be accounted for by assuming that strychnine and sarcophine derivatives compete for the same binding site on the receptor, so the less toxic sarcophine can prevent strychnine from binding. The combination of modulatory activity and low level of toxicity makes sarcophines attractive structures for novel glycinergic drugs.
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Affiliation(s)
- Hesham A Saleh
- Department of Pharmaceutical Chemistry, German University in Cairo, New Cairo, Egypt
| | - Karim M Raafat
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
| | - Tarek A Temraz
- Department of Marine Sciences, Suez Canal University, Ismailia, Egypt
| | - Nazih Noureldin
- Department of Pharmaceutical Chemistry, German University in Cairo, New Cairo, Egypt.
| | | | - Ulrike Breitinger
- Department of Biochemistry, German University in Cairo, New Cairo, Egypt
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Yan N, Du Y, Liu X, Zhang H, Liu Y, Zhang Z. A Review on Bioactivities of Tobacco Cembranoid Diterpenes. Biomolecules 2019; 9:E30. [PMID: 30654586 PMCID: PMC6359560 DOI: 10.3390/biom9010030] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 12/27/2018] [Accepted: 01/14/2019] [Indexed: 01/08/2023] Open
Abstract
Cembranoids are carbocyclic diterpenes comprising four isoprene units and are natural products with a parent skeleton consisting of a 14-membered ring. They have gained wide interest in recent years and are a major hotspot in the research of natural product chemistry. Since 1962, various tobacco cembranoid diterpenes have been identified. This review systematically discusses and summarises the excellent antimicrobial, insecticidal, cytotoxic and neuroprotective activities of tobacco cembranoid diterpenes. These compounds show potential to be developed as botanical fungicides, cytotoxic drugs and drugs for the treatment of human immunodeficiency virus, Alzheimer's disease, Parkinson's disease, and other neurodegenerative diseases. However, there are relatively few studies on the structure⁻activity relationship (SAR) of tobacco cembranoid diterpenes. Therefore, future studies should focus on their structural modification, SAR and biogenic relationships.
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Affiliation(s)
- Ning Yan
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Yongmei Du
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Xinmin Liu
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Hongbo Zhang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Yanhua Liu
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Zhongfeng Zhang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
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Farag MA, Maamoun AA, Meyer A, Wessjohann LA. Salicylic acid and its derivatives elicit the production of diterpenes and sterols in corals and their algal symbionts: a metabolomics approach to elicitor SAR. Metabolomics 2018; 14:127. [PMID: 30830394 DOI: 10.1007/s11306-018-1416-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/21/2018] [Indexed: 10/28/2022]
Abstract
INTRODUCTION The production of marine drugs in its normal habitats is often low and depends greatly on ecological conditions. Chemical synthesis of marine drugs is not economically feasible owing to their complex structures. Biotechnology application via elicitation represents a promising tool to enhance metabolites yield that has yet to be explored in soft corals. OBJECTIVES Study the elicitation impact of salicylic acid (SA) and six analogues in addition to a systemic acquired resistance inducer on secondary metabolites accumulation in the soft coral Sarcophyton ehrenbergi along with the symbiont zooxanthellae and if SA elicitation effect is extended to other coral species S. glaucum and Lobophyton pauciliforum. METHODS Post elicitation in the three corals and zooxanthella, metabolites were extracted and analyzed via UHPLC-MS coupled with chemometric tools. RESULTS Multivariate data analysis of the UHPLC-MS data set revealed clear segregation of SA, amino-SA, and acetyl-SA elicited samples. An increased level ca. 6- and 8-fold of the diterpenes viz., sarcophytonolide I, sarcophine and a C28-sterol, was observed in SA and amino-SA groups, respectively. Post elicitation, the level of diepoxy-cembratriene increased 1.5-fold and 2.4-fold in 1 mM SA, and acetyl-SA (aspirin) treatment groups, respectively. S. glaucum and Lobophyton pauciliforum showed a 2-fold increase of diepoxy-cembratriene levels. CONCLUSION These results suggest that SA could function as a general and somewhat selective diterpene inducing signaling molecule in soft corals. Structural consideration reveals initial structure-activity relationship (SAR) in SA derivatives that seem important for efficient diterpene and sterol elicitation.
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Affiliation(s)
- Mohamed A Farag
- Pharmacognosy Department, College of Pharmacy, Cairo University, Kasr El Aini St., P.B. 11562, Cairo, Egypt.
- Department of Chemistry, School of Sciences & Engineering, The American University in Cairo, New Cairo, 11835, Egypt.
| | - Amal A Maamoun
- 3Pharmacognosy Department, National Research Centre, 33 El-BuhouthSt., Dokki, P.O.12622, Giza, Egypt
| | - Achim Meyer
- Leibniz Centre for Tropical Marine Research, Fahrenheit Str.6, 28359, Bremen, Germany
| | - Ludger A Wessjohann
- Dept. Bioorganic Chemistry, Leibniz Institute of Plant Biochemistry, Weinberg 3, 06120, Halle (Saale), Germany
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Le‐Huu P, Rekow D, Krüger C, Bokel A, Heidt T, Schaubach S, Claasen B, Hölzel S, Frey W, Laschat S, Urlacher VB. Chemoenzymatic Route to Oxyfunctionalized Cembranoids Facilitated by Substrate and Protein Engineering. Chemistry 2018; 24:12010-12021. [DOI: 10.1002/chem.201802250] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/27/2018] [Indexed: 01/19/2023]
Affiliation(s)
- Priska Le‐Huu
- Institute of BiochemistryHeinrich-Heine University Düsseldorf Universitätsstrasse 1 40225 Düsseldorf Germany
| | - Dominik Rekow
- Institute of Organic ChemistryUniversity Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Claudia Krüger
- Institute of Organic ChemistryUniversity Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Ansgar Bokel
- Institute of BiochemistryHeinrich-Heine University Düsseldorf Universitätsstrasse 1 40225 Düsseldorf Germany
| | - Tanja Heidt
- Institute of Organic ChemistryUniversity Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Sebastian Schaubach
- Institute of Organic ChemistryUniversity Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Birgit Claasen
- Institute of Organic ChemistryUniversity Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Sebastian Hölzel
- Institute of BiochemistryHeinrich-Heine University Düsseldorf Universitätsstrasse 1 40225 Düsseldorf Germany
| | - Wolfgang Frey
- Institute of Organic ChemistryUniversity Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Sabine Laschat
- Institute of Organic ChemistryUniversity Stuttgart Pfaffenwaldring 55 70569 Stuttgart Germany
| | - Vlada B. Urlacher
- Institute of BiochemistryHeinrich-Heine University Düsseldorf Universitätsstrasse 1 40225 Düsseldorf Germany
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Hu J, Ferchmin PA, Hemmerle AM, Seroogy KB, Eterovic VA, Hao J. 4R-Cembranoid Improves Outcomes after 6-Hydroxydopamine Challenge in Both In vitro and In vivo Models of Parkinson's Disease. Front Neurosci 2017; 11:272. [PMID: 28611572 PMCID: PMC5447022 DOI: 10.3389/fnins.2017.00272] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 04/28/2017] [Indexed: 11/13/2022] Open
Abstract
(1S, 2E, 4R, 6R,-7E, 11E)-2, 7, 11-cembratriene-4, 6-diol (4R) is one of the cembranoids found in tobacco leaves. Previous studies have found that 4R protected acute rat hippocampal slices against neurotoxicity induced by N-methyl-D-aspartate (NMDA) and against the toxic organophosphorus compounds paraoxon and diisopropylfluorophosphate (DFP). Furthermore, in vivo, 4R reduced the infarct size in a rodent ischemic stroke model and neurodegeneration caused by DFP. The present study expanded our previous study by focusing on the effect of 4R in Parkinson's disease (PD) and elucidating its underlying mechanisms using 6-hydroxydopamine (6-OHDA)-induced injury models. We found that 4R exhibited significant neuroprotective activity in the rat unilateral 6-OHDA-induced PD model in vivo. The therapeutic effect was evident both at morphological and behavioral levels. 4R (6 and 12 mg/kg) treatments significantly improved outcomes of 6-OHDA-induced PD in vivo as indicated by reducing forelimb asymmetry scores and corner test scores 4 weeks after injection of 6-OHDA (p < 0.05). The therapeutic effect of 4R was also reflected by decreased depletion of tyrosine hydroxylase (TH) in the striatum and substantia nigra (SN) on the side injected with 6-OHDA. TH expression was 70.3 and 62.8% of the contralateral side in striatum and SN, respectively, after 6 mg/kg 4R treatment; furthermore, it was 80.1 and 79.3% after treatment with 12 mg/kg of 4R. In the control group, it was 51.9 and 23.6% of the contralateral striatum and SN (p < 0.05). Moreover, 4R also protected differentiated neuro-2a cells from 6-OHDA-induced cytotoxicity in vitro. The activation of p-AKT and HAX-1, and inhibition of caspase-3 and endothelial inflammation, were involved in 4R-mediated protection against 6-OHDA-induced injury. In conclusion, the present study indicates that 4R shows a therapeutic effect in the rat 6-OHDA-induced PD model in vivo and in 6-OHDA-challenged neuro-2a cells in vitro.
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Affiliation(s)
- Jing Hu
- Division of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of CincinnatiCincinnati, OH, United States
| | - P A Ferchmin
- Department of Neurosciences, School of Medicine, Universidad Central del CaribeBayamón, Puerto Rico
| | - Ann M Hemmerle
- Department of Neurology and Rehabilitation Medicine, University of CincinnatiCincinnati, OH, United States
| | - Kim B Seroogy
- Department of Neurology and Rehabilitation Medicine, University of CincinnatiCincinnati, OH, United States
| | - Vesna A Eterovic
- Department of Neurosciences, School of Medicine, Universidad Central del CaribeBayamón, Puerto Rico
| | - Jiukuan Hao
- Division of Pharmaceutical Sciences, James L. Winkle College of Pharmacy, University of CincinnatiCincinnati, OH, United States
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12
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Farag MA, Al-Mahdy DA, Meyer A, Westphal H, Wessjohann LA. Metabolomics reveals biotic and abiotic elicitor effects on the soft coral Sarcophyton ehrenbergi terpenoid content. Sci Rep 2017; 7:648. [PMID: 28381824 PMCID: PMC5428729 DOI: 10.1038/s41598-017-00527-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 03/01/2017] [Indexed: 01/06/2023] Open
Abstract
The effects of six biotic and abiotic elicitors, i.e. MeJA (methyl jasmonate), SA (salicylic acid), ZnCl2, glutathione and β-glucan BG (fungal elicitor), and wounding, on the secondary metabolite accumulation in the soft coral Sarcophyton ehrenbergi were assessed. Upon elicitation, metabolites were extracted and analysed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS). Except for MeJA, no differences in photosynthetic efficiency were observed after treatments, suggesting the absence of a remarkable stress on primary production. Chemometric analyses of UPLC-MS data showed clear segregation of SA and ZnCl2 elicited samples at 24 and 48 h post elicitation. Levels of acetylated diterpene and sterol viz., sarcophytonolide I and cholesteryl acetate, was increased in ZnCl2 and SA groups, respectively, suggesting an activation of specific acetyl transferases. Post elicitation, sarcophytonolide I level increased 132 and 17-folds at 48 h in 0.1 mM SA and 1 mM ZnCl2 groups, respectively. Interestingly, decrease in sarcophine, a major diterpene was observed only in response to ZnCl2, whereas no change was observed in sesquiterpene content following treatments. To the best of our knowledge, this study provides the first documentation for elicitation effects on a soft corals secondary metabolome and suggests that SA could be applied to increase diterpenoid levels in corals.
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Affiliation(s)
- Mohamed A Farag
- Pharmacognosy department, College of Pharmacy, Cairo University, Cairo, Kasr El Aini st., P.B. 11562, Egypt.
| | - Dalia A Al-Mahdy
- Pharmacognosy department, College of Pharmacy, Cairo University, Cairo, Kasr El Aini st., P.B. 11562, Egypt
| | - Achim Meyer
- Leibniz Centre for Tropical Marine Research, Fahrenheit Str.6, D-28359, Bremen, Germany
| | - Hildegard Westphal
- Leibniz Centre for Tropical Marine Research, Fahrenheit Str.6, D-28359, Bremen, Germany
- Bremen University, Bremen, Germany
| | - Ludger A Wessjohann
- Leibniz Institute of Plant Biochemistry, Dept. Bioorganic Chemistry, Weinberg 3, D-06120, Halle (Saale), Germany.
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13
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Bogdanov A, Hertzer C, Kehraus S, Nietzer S, Rohde S, Schupp PJ, Wägele H, König GM. Secondary metabolome and its defensive role in the aeolidoidean Phyllodesmium longicirrum, (Gastropoda, Heterobranchia, Nudibranchia). Beilstein J Org Chem 2017; 13:502-519. [PMID: 28405231 PMCID: PMC5372768 DOI: 10.3762/bjoc.13.50] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 02/08/2017] [Indexed: 11/23/2022] Open
Abstract
Phyllodesmium longicirrum is the largest aeolidoidean species known to date, and extremely rich in terpenoid chemistry. Herein we report the isolation of a total of 19 secondary metabolites from a single specimen of this species, i.e., steroids 1-4, cembranoid diterpenes 5-13, complex biscembranoids 14 and 15, and the chatancin-type diterpenes 16-19. These compounds resemble those from soft corals of the genus Sarcophyton, of which to date, however, only S. trocheliophorum is described as a food source for P. longicirrum. Fish feeding deterrent activity was determined using the tropical puffer fish Canthigaster solandri, and showed activity for (2S)-isosarcophytoxide (10), cembranoid bisepoxide 12 and 4-oxochatancin (16). Determining the metabolome of P. longicirrum and its bioactivity, makes it evident that this seemingly vulnerable soft bodied animal is well protected from fish by its chemical arsenal.
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Affiliation(s)
- Alexander Bogdanov
- Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
| | - Cora Hertzer
- Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
| | - Stefan Kehraus
- Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
| | - Samuel Nietzer
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl-von-Ossietzki University Oldenburg, Schleusenstraße 1, 26382 Wilhelmshaven, Germany
| | - Sven Rohde
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl-von-Ossietzki University Oldenburg, Schleusenstraße 1, 26382 Wilhelmshaven, Germany
| | - Peter J Schupp
- Institute for Chemistry and Biology of the Marine Environment (ICBM), Carl-von-Ossietzki University Oldenburg, Schleusenstraße 1, 26382 Wilhelmshaven, Germany
| | - Heike Wägele
- Zoologisches Forschungsmuseum Alexander Koenig, Adenauerallee 160, 53113 Bonn, Germany
| | - Gabriele M König
- Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany
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14
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Duan CBOTFAOTEAVMS, Du Y, Hou X, Yan N, Dong W, Mao X, Zhang Z. Chemical Basis of the Fungicidal Activity of Tobacco Extracts against Valsa mali. Molecules 2016; 21:E1743. [PMID: 27999348 PMCID: PMC6273253 DOI: 10.3390/molecules21121743] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 12/08/2016] [Accepted: 12/13/2016] [Indexed: 12/21/2022] Open
Abstract
Under pressure from social criticism and an unclear future, tobacco researchers have begun to seek alternative uses for the product. Here, we present our study on isolating tobacco compounds with fungicidal activity, which could be used as plant-derived pesticides. Using Valsa mali as the target fungus, agar plate tests were conducted to evaluate the fungicidal activity of various tobacco extracts, including tobacco leaves extracts prepared with different solvents, extracts of different tobacco cultivars, and samples from different tobacco organs. Fungal growth morphology was used as the criterion to evaluate the fungicidal activity of tobacco extracts. Correlation analyses between the fungicidal activities and the chemical components of tobacco extracts indicated the major chemical constituents with fungicidal activity. Then, the active compounds were isolated and their effects on the ultra-microstructures of V. mali was analyzed using scanning- and transmission-electron microscopy. The results suggested that tobacco extracts prepared with solvents of weaker polarity had higher fungicidal activity, and the inhibitory activity of tobacco extracts against V. mali was also cultivar dependent. Furthermore, the fungicidal effects of tobacco flower extracts were higher than those of the leaf extracts. Chemical analysis indicated that cembranoids were the main fungicidal substances, which act by destroying the endometrial structure of the fungus. Tobacco cembranoids at 80 μg/mL could completely inhibit the growth of V.mali, with an EC50 value of 13.18 μg/mL. Our study therefore suggests that tobacco leaves and inflorescences are excellent plant resources for the biological control of V. mali.
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Affiliation(s)
| | - Yongmei Du
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Xiaodong Hou
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Ning Yan
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
| | - Weijie Dong
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
- Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Xinxin Mao
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
- Graduate School of Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Zhongfeng Zhang
- Tobacco Research Institute of Chinese Academy of Agricultural Sciences, Qingdao 266101, China.
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15
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Le-Huu P, Petrović D, Strodel B, Urlacher VB. One-Pot, Two-Step Hydroxylation of the Macrocyclic Diterpenoid β-Cembrenediol Catalyzed by P450 BM3 Mutants. ChemCatChem 2016. [DOI: 10.1002/cctc.201600973] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Priska Le-Huu
- Institute of Biochemistry; Heinrich-Heine University Düsseldorf; Universitätsstrasse 1, Bldg. 26.42.U1 40225 Düsseldorf Germany
| | - Dušan Petrović
- Institute of Complex Systems: Structural Biochemistry (ICS-6); Forschungszentrum Jülich GmbH; 52425 Jülich Germany
| | - Birgit Strodel
- Institute of Complex Systems: Structural Biochemistry (ICS-6); Forschungszentrum Jülich GmbH; 52425 Jülich Germany
- Institute of Theoretical and Computational Chemistry; Heinrich-Heine University Düsseldorf; Universitätsstrasse 1 40225 Düsseldorf Germany
| | - Vlada B. Urlacher
- Institute of Biochemistry; Heinrich-Heine University Düsseldorf; Universitätsstrasse 1, Bldg. 26.42.U1 40225 Düsseldorf Germany
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16
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Ebrahim HY, Mohyeldin MM, Hailat MM, El Sayed KA. (1S,2E,4S,7E,11E)-2,7,11-Cembratriene-4,6-diol semisynthetic analogs as novel c-Met inhibitors for the control of c-Met-dependent breast malignancies. Bioorg Med Chem 2016; 24:5748-5761. [PMID: 27681240 PMCID: PMC5079820 DOI: 10.1016/j.bmc.2016.09.032] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 09/09/2016] [Accepted: 09/12/2016] [Indexed: 11/18/2022]
Abstract
(1S,2E,4S,6R,7E,11E)-2,7,11-Cembratriene-4,6-diol (1) and its 4-epi-analog (2) are the cembranoid precursors to several key flavor ingredients in most Nicotiana (tobacco) species. Nearly 40-60% of 1 and 2 are purposely degraded during the commercial tobacco fermentation. However, 1 and 2 display promising bioactivities, including anticancer. Breast cancer is the most diagnosed cancer in women and ranked second female disease killer. The receptor tyrosine kinase c-Met correlates with aggressiveness of certain breast cancer phenotypes and thus considered a valid therapeutic target. This study reports the discovery and optimization of the tobacco-based cembranoid 1 as a novel c-Met inhibitory scaffold using combined structure- and ligand-based approaches. 1 displayed antiproliferative, anti-migratory and anti-invasive effects against the c-Met overexpressing MDA-MB-231 breast cancer cells at moderate μM concentrations. The Z'-LYTE kinase platform and Western blot analysis identified c-Met as a potential macromolecular target. Rationally designed carbamate analogs were proposed to probe additional targeted c-Met interactions and improve the cellular potency. The 6-phenyl carbamate 3 showed enhanced c-Met inhibitory activity. Structure-activity relationships of different substituents on the 3's phenyl moiety were studied. The most active analog 20 showed potent in vitro anticancer activity against the MDA-MB-231 breast cancer cells at low μM concentrations, with minimal toxicity on the non-tumorigenic MCF-10A mammary epithelial cells. Cembranoid 20 potently inhibited the c-Met catalytic activity in Z'-LYTE kinase assay and various cellular c-Met-driven signaling pathways. Furthermore, 20 displayed a robust antitumor activity in a breast cancer xenograft athymic mouse model and thus promoted to the lead rank. Cembranoids are novel c-Met inhibitors appropriate for future use to control c-Met dependent malignancies.
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Affiliation(s)
- Hassan Y Ebrahim
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Drive, Monroe, LA 71201, USA
| | - Mohamed M Mohyeldin
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Drive, Monroe, LA 71201, USA
| | - Mohammad M Hailat
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Drive, Monroe, LA 71201, USA
| | - Khalid A El Sayed
- Department of Basic Pharmaceutical Sciences, School of Pharmacy, University of Louisiana at Monroe, 1800 Bienville Drive, Monroe, LA 71201, USA.
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17
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Ferchmin PA, Pérez D, Cuadrado BL, Carrasco M, Martins AH, Eterović VA. Neuroprotection Against Diisopropylfluorophosphate in Acute Hippocampal Slices. Neurochem Res 2015; 40:2143-51. [PMID: 26438150 DOI: 10.1007/s11064-015-1729-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 09/23/2015] [Indexed: 12/12/2022]
Abstract
Diisopropylfluorophosphate (DFP) is an irreversible inhibitor of acetylcholine esterase and a surrogate of the organophosphorus (OP) nerve agent sarin. The neurotoxicity of DFP was assessed as a reduction of population spike (PS) area elicited by synaptic stimulation in acute hippocampal slices. Two classical antidotes, atropine, and pralidoxime, and two novel antidotes, 4R-cembranotriene-diol (4R) and a caspase nine inhibitor, were tested. Atropine, pralidoxime, and 4R significantly protected when applied 30 min after DFP. The caspase inhibitor was neuroprotective when applied 5-10 min before or after DFP, suggesting that early synaptic apoptosis is responsible for the loss of PSs. It is likely that apoptosis starts at the synapses and, if antidotes are not applied, descends to the cell bodies, causing death. The acute slice is a reliable tool for mechanistic studies, and the assessment of neurotoxicity and neuroprotection with PS areas is, in general, pharmacologically congruent with in vivo results and predicts the effect of drugs in vivo. 4R was first found to be neuroprotective in slices and later we demonstrated that 4R is neuroprotective in vivo. The mechanism of neurotoxicity of OPs is not well understood, and there is a need for novel antidotes that could be discovered using acute slices.
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Affiliation(s)
- P A Ferchmin
- Department of Biochemistry, Universidad Central Del Caribe, School of Medicine, Ave. Laurel, Santa Juanita, Bayamón, PR, 00956, USA. .,, PO BOX 60327, Bayamón, PR, 00960-6032, USA.
| | - Dinely Pérez
- Department of Biochemistry, Universidad Central Del Caribe, School of Medicine, Ave. Laurel, Santa Juanita, Bayamón, PR, 00956, USA
| | - Brenda L Cuadrado
- Department of Biochemistry, Universidad Central Del Caribe, School of Medicine, Ave. Laurel, Santa Juanita, Bayamón, PR, 00956, USA
| | - Marimée Carrasco
- Department of Biochemistry, Universidad Central Del Caribe, School of Medicine, Ave. Laurel, Santa Juanita, Bayamón, PR, 00956, USA
| | - Antonio H Martins
- Department of Pharmacology and Toxicology, Medical Science Campus UPR, San Juan, PR, USA
| | - Vesna A Eterović
- Department of Biochemistry, Universidad Central Del Caribe, School of Medicine, Ave. Laurel, Santa Juanita, Bayamón, PR, 00956, USA
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18
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Heidt T, Baro A, Köhn A, Laschat S. Synthesis of Cembranoid Analogues through Ring-Closing Metathesis of Terpenoid Precursors: A Challenge Regarding Ring-Size Selectivity. Chemistry 2015; 21:12396-404. [PMID: 26227568 DOI: 10.1002/chem.201502051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Tanja Heidt
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany)
| | - Angelika Baro
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany)
| | - Andreas Köhn
- Institut für Theoretische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany)
| | - Sabine Laschat
- Institut für Organische Chemie, Universität Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany).
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19
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Vélez-Carrasco W, Green CE, Catz P, Furimsky A, O’Loughlin K, Eterović VA, Ferchmin PA. Pharmacokinetics and Metabolism of 4R-Cembranoid. PLoS One 2015; 10:e0121540. [PMID: 25811857 PMCID: PMC4374761 DOI: 10.1371/journal.pone.0121540] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 02/03/2015] [Indexed: 11/18/2022] Open
Abstract
4R-cembranoid (4R) is a natural cyclic diterpenoid found in tobacco leaves that displays neuroprotective activity. 4R protects against NMDA, paraoxon (POX), and diisopropylfluorophosphate (DFP) damage in rat hippocampal slices and against DFP in rats in vivo. The purpose of this study was to examine the metabolism and pharmacokinetics of 4R as part of its preclinical development as a neuroprotective drug. 10 µM 4R was found to be very stable in plasma for up to 1 hr incubation. 4R metabolism in human microsomes was faster than in the rat. Ten metabolites of 4R were detected in the microsomal samples; 6 dihydroxy and 4 monohydroxy forms of 4R. Male rats received a single dose of 4R at 6 mg/kg i.v., i.m., or s.c. The i.v. group had the highest plasma concentration of 1017 ng/mL. The t1/2 was 36 min and reached the brain within 10 min. The brain peak concentration was 6516 ng/g. The peak plasma concentration in the i.m. group was 163 ng/mL compared to 138 ng/mL in the s.c. group. The t1/2 of 4R after i.m. and s.c. administration was approximately 1.5 hr. The brain peak concentration was 329 ng/g in the i.m. group and 323 ng/g for the s.c. group. The brain to plasma ratio in the i.v. group was 6.4, reached 10 min after dose, whereas in the i.m. and s.c. groups was 2.49 and 2.48, respectively, at 90 min after dose. Our data show that 4R crosses the BBB and concentrates in the brain where it exerts its neuroprotective effect.
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Affiliation(s)
- Wanda Vélez-Carrasco
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, Puerto Rico, United States of America
| | - Carol E. Green
- SRI International Biosciences Division, Menlo Park, California, United States of America
| | - Paul Catz
- SRI International Biosciences Division, Menlo Park, California, United States of America
| | - Anna Furimsky
- SRI International Biosciences Division, Menlo Park, California, United States of America
| | - Kathleen O’Loughlin
- SRI International Biosciences Division, Menlo Park, California, United States of America
| | - Vesna A. Eterović
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, Puerto Rico, United States of America
| | - P. A. Ferchmin
- Department of Biochemistry, Universidad Central del Caribe, Bayamon, Puerto Rico, United States of America
- * E-mail:
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20
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Vasamsetty L, Khan FA, Mehta G. A model approach towards the polycyclic framework present in cembranoid natural products dissectolide A, plumarellide and mandapamate. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.10.141] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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21
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Leong RL, Xing H, Braekman JC, Kem WR. Non-competitive Inhibition of Nicotinic Acetylcholine Receptors by Ladybird Beetle Alkaloids. Neurochem Res 2014; 40:2078-86. [PMID: 25370792 DOI: 10.1007/s11064-014-1466-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2014] [Revised: 10/15/2014] [Accepted: 10/25/2014] [Indexed: 12/01/2022]
Abstract
Ladybird beetles (Family Coccinellidae) secrete an alkaloid rich venom from their leg joints that protects them from predators. Coccinellines, the major venom constituents, are alkaloids composed of three fused piperidine rings that share a common nitrogen atom. Although many coccinellines have been isolated and chemically characterized, their pharmacological properties are essentially unknown. Using radioligand binding and functional assays we investigated the actions of several coccinellines on skeletal muscle and α7 nicotinic acetylcholine receptors (nAChRs). The alkaloids were shown to displace the specific binding of tritiated piperidyl-N-(1-(2-thienyl)cyclohexyl)-3,4-piperidine ([(3)H]-TCP), which has been shown to bind deep within the ion channel of the electric fish (Torpedo) muscle nAChR. The stereoisomers precoccinelline and hippodamine (whose nitrogens are predicted to be ionized at physiological pH) and their respective analogs N-methyl-precoccinelline and N-methyl-hippodamine (whose quaternary nitrogens are permanently charged) displayed similar IC50s for inhibition of [(3)H]-TCP binding. However, the corresponding precoccinelline and hippodamine N-oxides, coccinelline and convergine (which have an electronegative oxygen bonded to an electropositive nitrogen) displayed significantly higher binding IC50s. Finally, exochomine, a dimeric coccinelline containing the hippodamine structure, displayed the highest IC50 (lowest affinity) for displacing specific [(3)H]-TCP binding. The presence of a desensitizing concentration (10(-3) M) of carbachol (CCh) had little or no effect on the affinity of the Torpedo nAChR for the three coccinellines tested. High concentrations of the coccinellid alkaloids did not affect binding of [(3)H]-cytisine to Torpedo receptor ACh binding sites. Inhibition of the alpha7 nAChR with pre-equilibrated precoccinelline was insurmountable with respect to ACh concentration. We conclude that the coccinellines bind to one or more allosteric sites rather than to the ACh binding sites, and inhibit nAChR responses to ACh through a non-competitive mechanism. Future chemical and pharmacological investigations of other ladybird beetle alkaloids are likely to reveal other interesting alkaloids affecting ligand-gated receptors.
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Affiliation(s)
- Ron L Leong
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, 32610, USA
| | - Hong Xing
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, 32610, USA
| | - Jean-Claude Braekman
- Laboratory of Bioorganic Chemistry, Faculty of Sciences, University of Brussels, 1050, Brussels, Belgium
| | - William R Kem
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, 32610, USA.
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22
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Qian XB, Ye JP, Chen XM, Zhang CH, Liang YJ, Li ZH, Yang J. Analysis of Cembranoids in Flue-cured Tobacco by Accelerated Solvent Extraction and Gas Chromatography-Mass Spectrometry-Selected Ion Monitoring. J CHIN CHEM SOC-TAIP 2014. [DOI: 10.1002/jccs.201400045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Ferchmin PA, Andino M, Reyes Salaman R, Alves J, Velez-Roman J, Cuadrado B, Carrasco M, Torres-Rivera W, Segarra A, Martins AH, Lee JE, Eterovic VA. 4R-cembranoid protects against diisopropylfluorophosphate-mediated neurodegeneration. Neurotoxicology 2014; 44:80-90. [PMID: 24928201 DOI: 10.1016/j.neuro.2014.06.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Revised: 06/01/2014] [Accepted: 06/01/2014] [Indexed: 11/26/2022]
Abstract
Many organophosphorous esters synthesized for applications in industry, agriculture, or warfare irreversibly inhibit acetylcholinesterase, and acute poisoning with these compounds causes life-threatening cholinergic overstimulation. Following classical emergency treatment with atropine, an oxime, and a benzodiazepine, surviving victims often suffer brain neurodegeneration. Currently, there is no pharmacological treatment to prevent this brain injury. Here we show that a cyclic diterpenoid, (1S,2E,4R,6R,7E,11E)-cembra-2,7,11-triene-4,6-diol (4R) ameliorates the damage caused by diisopropylfluorophosphate (DFP) in the hippocampal area CA1. DFP has been frequently used as a surrogate for the warfare nerve agent sarin. In rats, DFP is lethal at the dose used to cause brain damage. Therefore, to observe brain damage in survivors, the death rate was reduced by pre-administration of the peripherally acting antidotes pyridostigmine and methyl atropine or its analog ipratropium. Pyridostigmine bromide, methyl atropine nitrate, and ipratropium bromide were dissolved in saline and injected intramuscularly at 0.1mg/kg, 20mg/kg, and 23mg/kg, respectively. DFP (9mg/kg) dissolved in cold water was injected intraperitoneally. 4R (6mg/kg) dissolved in DMSO was injected subcutaneously, either 1h before or 5 or 24h after DFP. Neurodegeneration was assessed with Fluoro-Jade B and amino cupric silver staining; neuroinflammation was measured by the expression of nestin, a marker of activated astrocytes. Forty-eight hours after DFP administration, 4R decreased the number of dead neurons by half when injected before or after DFP. 4R also significantly decreased the number of activated astrocytes. These data suggest that 4R is a promising new drug that could change the therapeutic paradigm for acute poisoning with organophosphorous compounds by the implementation of a second-stage intervention after the classical countermeasure treatment.
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Affiliation(s)
- P A Ferchmin
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA.
| | - Myrna Andino
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
| | - Rebeca Reyes Salaman
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
| | - Janaina Alves
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
| | - Joyce Velez-Roman
- Department of Pharmacology, University of Puerto Rico Medical Sciences Campus, San Juan, PR 00936, USA
| | - Brenda Cuadrado
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
| | - Marimeé Carrasco
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
| | - Wilmarie Torres-Rivera
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
| | - Annabell Segarra
- Department of Pharmacology, University of Puerto Rico Medical Sciences Campus, San Juan, PR 00936, USA
| | - Antonio Henrique Martins
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
| | - Jae Eun Lee
- RTRN Data Coordinating Center, Jackson State University, Jackson, MI 39204, USA
| | - Vesna A Eterovic
- Department of Biochemistry, Universidad Central del Caribe School of Medicine, Bayamón, PR 00960, USA
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24
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Abstract
This review covers the isolation, chemical structure, biological activity, structure activity relationships including synthesis of chemical probes, and pharmacological characterization of neuroactive marine natural products; 302 references are cited.
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Affiliation(s)
- Ryuichi Sakai
- Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan.
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Görner C, Häuslein I, Schrepfer P, Eisenreich W, Brück T. Targeted Engineering of Cyclooctat-9-en-7-ol Synthase: A Stereospecific Access to Two New Non-natural Fusicoccane-Type Diterpenes. ChemCatChem 2013. [DOI: 10.1002/cctc.201300285] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Protective activity of (1S,2E,4R,6R,7E,11E)-2,7,11-cembratriene-4,6-diol analogues against diisopropylfluorophosphate neurotoxicity: preliminary structure-activity relationship and pharmacophore modeling. Bioorg Med Chem 2013; 21:4678-86. [PMID: 23769165 DOI: 10.1016/j.bmc.2013.05.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 05/03/2013] [Accepted: 05/10/2013] [Indexed: 01/09/2023]
Abstract
Diisopropylfluorophosphate (DFP) is an organophosphorous insecticide used as a surrogate for the more toxic chemical warfare nerve agent sarin. DFP produces neurotoxicity in vivo and irreversibly decreases the area of population spikes recorded from the CA1 region of acute hippocampal slices. (1S,2E,4R,6R,7E,11E)-2,7,11-Cembratriene-4,6-diol (1) is a neuroprotective natural cembranoid that reverses DFP-induced damage both in vivo and in the hippocampal slice. Cembranoid 1 acts by noncompetitive inhibition of the α7 nicotinic acetylcholine receptor. This study aims at establishing a preliminary structure-activity relationship to define the neuroprotective cembranoid pharmacophores using the hippocampal slice assay and pharmacophore modeling. Fourteen natural, semisynthetic, or biocatalytic cembranoid analogues 2-15 related to 1 were tested for their capacity to protect the population spikes from DFP-induced damage and intrinsic toxicity. Twelve cembranoids caused significant reversal of DFP toxicity; only 3 active analogues displayed minor intrinsic toxicity at 10 μM. The C-4 epimer of 1 (2) and the 4-O-methyl ether analogue of 1 (3), were totally devoid of neuroprotective activity. The results suggested a model for cembranoid binding where the hydrophobic ring surface binds to a hydrophobic (Hbic) patch on the receptor molecule and an electronegative atom (oxygen or sulfur) in proper spatial relationship to the ring surface interacts with an electropositive group in the receptor binding site. A pharmacophore model consisting of 1 hydrogen bond acceptor (HBA), 2 Hbic, and 10 exclusion spheres was established using HipHop-REFINE and supported the above mentioned pharmacophoric hypothesis.
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Nunes-Alves A, Nery AA, Ulrich H. Tobacco nitrosamine N-nitrosonornicotine as inhibitor of neuronal nicotinic acetylcholine receptors. J Mol Neurosci 2012; 49:52-61. [PMID: 22847530 DOI: 10.1007/s12031-012-9859-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 07/12/2012] [Indexed: 12/22/2022]
Abstract
Nitrosamines are well known for their carcinogenic potential. Recently, it was found that some of them may also interact with human nicotinic acetylcholine receptor (nAChR) subtypes. This work studied the effects of N-nitrosonornicotine (NNN) on recombinant rat α3β4 nAChR in HEK cells as well as on nAChR endogenously expressed in PC12 pheochromocytoma cells and in BC3H1 muscle-type cells. Whole-cell recording in combination with the cell-flow technique for agonist and inhibitor application in the millisecond time region revealed that NNN inhibits the activity of neuronal nAChR expressed in HEK or PC12, whereas weak inhibitory effects on muscle-type nAChR were observed at NNN concentrations up to 3 mM. Pharmacological actions of NNN and the inhibition mechanism were studied in detail using recombinant α3β4 nAChR expressed in HEK cells as a model. NNN-induced inhibition of nicotine-evoked α3β4 nAChR activity was dose-dependent with an inhibitory constant (IC(50)) of 0.92 ± 0.05 mM. Analysis based on mathematical models indicated a noncompetitive inhibition mechanism of the rat α3β4 nAChR by NNN. NNN's mechanism of action involves acceleration of conversion of the receptor from active to desensitized forms. In summary, this work shows that NNN inhibits rat α3β4 nAChR in a noncompetitive way and interacts weakly with muscular nAChR.
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Affiliation(s)
- Ariane Nunes-Alves
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, Av. Prof. Lineu Prestes 748, São Paulo, São Paulo 05508-900, Brazil
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Cheffer A, Mustafa EV, T-do Amaral A, Ulrich H. Lipophilicity as a determinant of binding of procaine analogs to rat α3β4 nicotinic acetylcholine receptor. J Neurosci Res 2012; 90:1607-14. [PMID: 22504865 DOI: 10.1002/jnr.23047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 01/19/2012] [Accepted: 01/31/2012] [Indexed: 11/10/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) have been studied in detail with regard to their interaction with therapeutic and drug addiction-related compounds. Using a structure-activity approach, we have examined the relationship among the molecular features of a set of eight para-R-substituted N,N-[(dimethylamino)ethyl] benzoate hydrochlorides, structurally related to procaine and their affinity for the α(3)β(4) nAChR heterologously expressed in KXα3β4R2 cells. Affinity values (log[1/IC50]) of these compounds for the α(3)β(4) nAChR were determined by their competition with [(3)H]TCP binding. Log(1/IC50) values were analyzed considering different hydrophobic and electronic parameters and those related to molar refractivity. These have been experimentally determined or were taken from published literature. In accordance with literature observations, the generated cross-validated quantitative structure-activity relationship (QSAR) equations indicated a significant contribution of hydrophobic term to binding affinity of procaine analogs to the receptor and predicted affinity values for several local anesthetics (LAs) sets taken from the literature. The predicted values by using the QSAR model correlated well with the published values both for neuronal and for electroplaque nAChRs. Our work also reveals the general structure features of LAs that are important for interaction with nAChRs as well as the structural modifications that could be made to enhance binding affinity.
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Affiliation(s)
- Arquimedes Cheffer
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
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Eterović VA, Pérez D, Martins AH, Cuadrado BL, Carrasco M, Ferchmin PA. A cembranoid protects acute hippocampal slices against paraoxon neurotoxicity. Toxicol In Vitro 2011; 25:1468-74. [PMID: 21569834 DOI: 10.1016/j.tiv.2011.04.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 04/01/2011] [Accepted: 04/22/2011] [Indexed: 11/18/2022]
Abstract
Many neurotoxic organophosphates (OPs) inhibit acetylcholinesterase (AChE) and as a result can cause a life threatening cholinergic crisis. Current medical countermeasures, which typically include atropine and oximes target the cholinergic crisis and are effective in decreasing mortality but do not sufficiently protect against delayed neurological deficits. There is, therefore, a need to develop neuroprotective drugs to prevent long-term neurological deficits. We used acute hippocampal slices to test the hypothesis that 4R,6R-cembratrienediol (4R) protects against functional damage caused by the OP paraoxon (POX). To assess hippocampal function, we measured synaptically evoked population spikes (PSs). Application of 4R reversed POX inhibition of PSs and the EC(50) of this effect was 0.8 μM. Atropine alone did not protect against POX neurotoxicity, but it did enhance protection by 4R. Pralidoxime partially regenerated AChE activity and protected against POX inhibition of PSs. 4R did not regenerate AChE suggesting that under our experimental conditions, the deleterious effect of POX on hippocampal function is not directly related to AChE inhibition. In conclusion, 4R is a promising neuroprotective compound against OP neurotoxins.
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Affiliation(s)
- Vesna A Eterović
- Department of Biochemistry, Universidad Central Del Caribe, Bayamón, PR 00960-6032
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Cheffer A, Ulrich H. Inhibition mechanism of rat α₃β₄ nicotinic acetylcholine receptor by the Alzheimer therapeutic tacrine. Biochemistry 2011; 50:1763-70. [PMID: 21247200 DOI: 10.1021/bi101789y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Nicotinic acetylcholine receptors (nAChRs) were studied in detail in the past regarding their interaction with therapeutic and drug addiction related compounds. Using fast kinetic whole-cell recording, we have now studied effects of tacrine, an agent used clinically to treat Alzheimer's disease, on currents elicited by activation of rat α(3)β(4) nAChR heterologously expressed in KXα3β4R2 cells. Characterization of receptor activation by nicotine used as agonist revealed a K(d) of 23 ± 0.2 μM and 4.3 ± 1.3 for the channel opening equilibrium constant, Φ(-1). Experiments were performed to investigate whether tacrine is able to activate the α(3)β(4) nAChR. Tacrine did not activate whole-cell currents in KXα3β4R2 cells but inhibited receptor activity at submicromolar concentration. Dose-response curves obtained with increasing agonist or inhibitor concentration revealed competitive inhibition of nAChRs by tacrine, with an apparent inhibition constant, K(I), of 0.8 μM. The increase of Φ(-1) in the presence of tacrine suggests that the drug stabilizes a nonconducting open channel form of the receptor. Binding studies with TCP and MK-801 ruled out tacrine binding to common allosteric sites of the receptor. Our study suggests a novel mechanism for action of tacrine on nAChRs besides inhibition of acetylcholine esterase.
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Affiliation(s)
- Arquimedes Cheffer
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo 05508-900, Brazil
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New lobane and cembrane diterpenes from two comorian soft corals. Mar Drugs 2010; 8:359-72. [PMID: 20390110 PMCID: PMC2852843 DOI: 10.3390/md8020359] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Revised: 02/08/2010] [Accepted: 02/20/2010] [Indexed: 01/24/2023] Open
Abstract
Preliminary biological investigation of a collection of Comorian soft corals resulted in the selection of two specimens, one of Sarcophyton and the other of Lobophytum, on the basis of their toxicity on larvae of the brine shrimp (Artemia salina) and inhibition of acetylcholinesterase, respectively. Bioassay-guided fractionations provided a known antitumor promoter cembrane diterpenoid, (+)-sarcophytol-A (1), along with a new lobane diterpenoid, carbomethoxyfuscol (2), from Sarcophyton sp., and a new cembranoid, crassumolide E (3), from Lobophytum sp. The structures of compounds 1–3 were determined by spectroscopic analysis and by comparison of the spectral data with previously reported values. The cembranoid 3 was found to exhibit a moderate inhibitory effect on acetylcholinesterase.
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Arias HR. Positive and negative modulation of nicotinic receptors. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2010; 80:153-203. [PMID: 21109220 DOI: 10.1016/b978-0-12-381264-3.00005-9] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nicotinic acetylcholine receptors (AChRs) are one of the best characterized ion channels from the Cys-loop receptor superfamily. The study of acetylcholine binding proteins and prokaryotic ion channels from different species has been paramount for the understanding of the structure-function relationship of the Cys-loop receptor superfamily. AChR function can be modulated by different ligand types. The neurotransmitter ACh and other agonists trigger conformational changes in the receptor, finally opening the intrinsic cation channel. The so-called gating process couples ligand binding, located at the extracellular portion, to the opening of the ion channel, located at the transmembrane region. After agonist activation, in the prolonged presence of agonists, the AChR becomes desensitized. Competitive antagonists overlap the agonist-binding sites inhibiting the pharmacological action of agonists. Positive allosteric modulators (PAMs) do not bind to the orthostetic binding sites but allosterically enhance the activity elicited by agonists by increasing the gating process (type I) and/or by decreasing desensitization (type II). Instead, negative allosteric modulators (NAMs) produce the opposite effects. Interestingly, this negative effect is similar to that found for another class of allosteric drugs, that is, noncompetitive antagonists (NCAs). However, the main difference between both categories of drugs is based on their distinct binding site locations. Although both NAMs and NCAs do not bind to the agonist sites, NACs bind to sites located in the ion channel, whereas NAMs bind to nonluminal sites. However, this classification is less clear for NAMs interacting at the extracellular-transmembrane interface where the ion channel mouth might be involved. Interestingly, PAMs and NAMs might be developed as potential medications for the treatment of several diseases involving AChRs, including dementia-, skin-, and immunological-related diseases, drug addiction, and cancer. More exciting is the potential combination of specific agonists with specific PAMs. However, we are still in the beginning of understanding how these compounds act and how these drugs can be used therapeutically.
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Affiliation(s)
- Hugo R Arias
- Department of Pharmaceutical Sciences, Midwestern University, Glendale, AZ, USA
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Dome P, Lazary J, Kalapos MP, Rihmer Z. Smoking, nicotine and neuropsychiatric disorders. Neurosci Biobehav Rev 2009; 34:295-342. [PMID: 19665479 DOI: 10.1016/j.neubiorev.2009.07.013] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2009] [Revised: 07/23/2009] [Accepted: 07/30/2009] [Indexed: 12/20/2022]
Abstract
Tobacco smoking is an extremely addictive and harmful form of nicotine (NIC) consumption, but unfortunately also the most prevalent. Although disproportionately high frequencies of smoking and its health consequences among psychiatric patients are widely known, the neurobiological background of this epidemiological association is still obscure. The diverse neuroactive effects of NIC and some other major tobacco smoke constituents in the central nervous system may underlie this association. This present paper summarizes the pharmacology of NIC and its receptors (nAChR) based on a systematic review of the literature. The role of the brain's reward system(s) in NIC addiction and the results of functional and structural neuroimaging studies on smoking-related states and behaviors (i.e. dependence, craving, withdrawal) are also discussed. In addition, the epidemiological, neurobiological, and genetic aspects of smoking in several specific neuropsychiatric disorders are reviewed and the clinical relevance of smoking in these disease states addressed.
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Affiliation(s)
- Peter Dome
- Department of Clinical and Theoretical Mental Health, Kutvolgyi Clinical Center, Semmelweis University, Faculty of Medicine, Kutvolgyi ut 4, 1125 Budapest, Hungary.
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Abstract
Cnidarians (Coelenterates), a very old and diverse animal phylum, possess a wide variety of biologically active substances that can be considered as toxins. Anthozoan toxins can be classified into two chemically very different groups, namely polypeptide toxins isolated from sea anemones and diterpenes isolated from octocorals. Cubozoan and scyphozoan protein toxins have been the most elusive cnidarian toxins to investigate - despite a tremendous effort in the past few decades, very few of these large, relatively unstable protein toxins were isolated, but recently this has been achieved for cubozoan venoms. Hydrozoans mainly contain large proteins with physiological mechanisms of action similar to the sea anemone and jellyfish pore-forming toxins. This article will focus on the in vivo physiological effects of cnidarian toxins and venoms; their actions at the cellular level will only be considered to understand their actions at the organ and whole animal levels. An understanding of mechanisms underlying the in vivo toxic effects will facilitate the development of more effective treatments of cnidarian envenomations.
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Affiliation(s)
- Dusan Suput
- University of Ljubljana, Faculty of Medicine, Vrazov trg 2, 1104 Ljubljana, Slovenia.
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