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Metabolic Toxification of 1,2-Unsaturated Pyrrolizidine Alkaloids Causes Human Hepatic Sinusoidal Obstruction Syndrome: The Update. Int J Mol Sci 2021; 22:ijms221910419. [PMID: 34638760 PMCID: PMC8508847 DOI: 10.3390/ijms221910419] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 09/09/2021] [Accepted: 09/14/2021] [Indexed: 12/15/2022] Open
Abstract
Saturated and unsaturated pyrrolizidine alkaloids (PAs) are present in more than 6000 plant species growing in countries all over the world. They have a typical heterocyclic structure in common, but differ in their potential toxicity, depending on the presence or absence of a double bond between C1 and C2. Fortunately, most plants contain saturated PAs without this double bond and are therefore not toxic for consumption by humans or animals. In a minority of plants, however, PAs with this double bond between C1 and C2 exhibit strong hepatotoxic, genotoxic, cytotoxic, neurotoxic, and tumorigenic potentials. If consumed in error and in large emouns, plants with 1,2-unsaturated PAs induce metabolic breaking-off of the double bonds of the unsaturated PAs, generating PA radicals that may trigger severe liver injury through a process involving microsomal P450 (CYP), with preference of its isoforms CYP 2A6, CYP 3A4, and CYP 3A5. This toxifying CYP-dependent conversion occurs primarily in the endoplasmic reticulum of the hepatocytes equivalent to the microsomal fraction. Toxified PAs injure the protein membranes of hepatocytes, and after passing their plasma membranes, more so the liver sinusoidal endothelial cells (LSECs), leading to life-threatening hepatic sinusoidal obstruction syndrome (HSOS). This injury is easily diagnosed by blood pyrrolizidine protein adducts, which are perfect diagnostic biomarkers, supporting causality evaluation using the updated RUCAM (Roussel Uclaf Causality Assessment Method). HSOS is clinically characterized by weight gain due to fluid accumulation (ascites, pleural effusion, and edema), and may lead to acute liver failure, liver transplantation, or death. In conclusion, plant-derived PAs with a double bond between C1 and C2 are potentially hepatotoxic after metabolic removal of the double bond, and may cause PA-HSOS with a potential lethal outcome, even if PA consumption is stopped.
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Trifan A, Wolfram E, Esslinger N, Grubelnik A, Skalicka-Woźniak K, Minceva M, Luca SV. Globoidnan A, rabdosiin and globoidnan B as new phenolic markers in European-sourced comfrey (Symphytum officinale L.) root samples. PHYTOCHEMICAL ANALYSIS : PCA 2021; 32:482-494. [PMID: 33015885 DOI: 10.1002/pca.2996] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 09/03/2020] [Accepted: 09/07/2020] [Indexed: 05/25/2023]
Abstract
INTRODUCTION Symphytum officinale L. (comfrey, Boraginaceae) is a cultivated or spontaneously growing medicinal plant that is traditionally used for the treatment of bone fractures, hematomas, muscle pains and joint pains. A wide range of topical preparations and dried roots for ex tempore applications are marketed in European drug stores or pharmacies. OBJECTIVE The aim of this study was to perform the qualitative and quantitative analysis of pyrrolizidine alkaloids (PAs) and phenolic compounds in the hydroethanolic extracts of 16 commercial comfrey root batches purchased from 12 different European countries. METHODS Liquid chromatography hyphenated with high-resolution tandem mass spectrometry (LC-HRMS/MS) was used for the profiling of PAs and phenolic compounds, whereas LC-MS/MS and liquid chromatography with diode array detection (LC-DAD) were used for their quantification. RESULTS 20 PAs (i.e. intermedine, lycopsamine, acetylintermedine, acetyllycopsamine, symphytine, symphytine-N-oxide), 17 phenolic compounds (i.e. caffeic and rosmarinic acids, rabdosiin, globoidnan A, globoidnan B) and 9 nonphenolic compounds (sugars, organic and fatty acids) were fully or partly annotated in the analysed samples. In addition, the quantitative analyses revealed that globoidnan B, rabdosiin and globoidnan A are new phenolic markers that can be used together with rosmarinic acid and PAs for the quality control of commercial comfrey root batches. CONCLUSIONS This study brings new insights into the phytochemical complexity of S. officinale, revealing not only numerous toxic PAs, but also a significant number of valuable phenolic compounds that could contribute to the bioactivities of comfrey-based preparations.
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Affiliation(s)
- Adriana Trifan
- Department of Pharmacognosy, Grigore T. Popa University of Medicine and Pharmacy Iasi, Iasi, 700115, Romania
| | - Evelyn Wolfram
- Phytopharmacy and Natural Products Research Group, Zurich University of Applied Sciences, Wädenswil, 8820, Switzerland
| | | | | | - Krystyna Skalicka-Woźniak
- Independent Laboratory of Natural Products Chemistry, Department of Pharmacognosy, Medical University of Lublin, Lublin, 20-093, Poland
| | - Mirjana Minceva
- Biothermodynamics, TUM School of Life and Food Sciences Weihenstephan, Technical University of Munich, Freising, 85354, Germany
| | - Simon Vlad Luca
- Biothermodynamics, TUM School of Life and Food Sciences Weihenstephan, Technical University of Munich, Freising, 85354, Germany
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Kopp T, Abdel-Tawab M, Mizaikoff B. Extracting and Analyzing Pyrrolizidine Alkaloids in Medicinal Plants: A Review. Toxins (Basel) 2020; 12:E320. [PMID: 32413969 PMCID: PMC7290370 DOI: 10.3390/toxins12050320] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 04/27/2020] [Accepted: 05/05/2020] [Indexed: 12/11/2022] Open
Abstract
Pyrrolizidine alkaloids (PAs) are distributed in plant families of Asteraceae, Boraginaceae, and Fabaceae and serve in the chemical defense mechanism against herbivores. However, they became a matter of concern due to their toxicity associated with the high risk of intake within herbal preparations, e.g., phytopharmaceutical formulations, medicinal teas, or other plant-derived drug products. In 1992, the German Federal Ministry of Health established the first limits of PA content for fourteen medicinal plants. Because of the toxic effects of PAs, the Federal Institute of Risk Assessment (BfR) established more stringent limits in 2011, whereby a daily intake <0.007 µg/kg body weight was recommended and valid until 2018. A threefold higher limit was then advised by BfR. To address consumer safety, there is the need for more efficient extraction procedures along with robust, selective, and sensitive analytical methods to address these concerns. With the increased prevalence of, e.g., phytopharmaceutical formulations, this timely review comprehensively focuses on the most relevant extraction and analysis strategies for each of those fourteen plant genera. While a variety of extraction procedures has been reported, differences in PA content of up to 1110 ppm (0.11% (w/w)) were obtained dependent on the nature of the solvent and the applied extraction technique. It is evident that the efficient extraction of PAs requires further improvements or at least standardization of the extraction conditions. Comparing the various analytical techniques applied regarding selectivity and sensitivity, LC-MS methods appear most suited. This review shows that both standardized extraction and sensitive determination of PAs is required for achieving appropriate safety levels concerning public health in future.
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Affiliation(s)
- Thomas Kopp
- Department of Chemistry, Institute of Analytical and Bioanalytical Chemistry, Ulm University, 89081 Ulm, Germany;
- Central Laboratory of German Pharmacists, 65760 Eschborn, Germany;
| | - Mona Abdel-Tawab
- Central Laboratory of German Pharmacists, 65760 Eschborn, Germany;
| | - Boris Mizaikoff
- Department of Chemistry, Institute of Analytical and Bioanalytical Chemistry, Ulm University, 89081 Ulm, Germany;
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Kellogg JJ, Paine MF, McCune JS, Oberlies NH, Cech NB. Selection and characterization of botanical natural products for research studies: a NaPDI center recommended approach. Nat Prod Rep 2019; 36:1196-1221. [PMID: 30681109 PMCID: PMC6658353 DOI: 10.1039/c8np00065d] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Covering: up to the end of 2018 Dietary supplements, which include botanical (plant-based) natural products, constitute a multi-billion-dollar industry in the US. Regulation and quality control for this industry is an ongoing challenge. While there is general agreement that rigorous scientific studies are needed to evaluate the safety and efficacy of botanical natural products used by consumers, researchers conducting such studies face a unique set of challenges. Botanical natural products are inherently complex mixtures, with composition that differs depending on myriad factors including variability in genetics, cultivation conditions, and processing methods. Unfortunately, many studies of botanical natural products are carried out with poorly characterized study material, such that the results are irreproducible and difficult to interpret. This review provides recommended approaches for addressing the critical questions that researchers must address prior to in vitro or in vivo (including clinical) evaluation of botanical natural products. We describe selection and authentication of botanical material and identification of key biologically active compounds, and compare state-of-the-art methodologies such as untargeted metabolomics with more traditional targeted methods of characterization. The topics are chosen to be of maximal relevance to researchers, and are reviewed critically with commentary as to which approaches are most practical and useful and what common pitfalls should be avoided.
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Affiliation(s)
- Joshua J. Kellogg
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA.
| | - Mary F. Paine
- Department of Pharmaceutical Sciences, College of Pharmacy, Washington State University, Spokane, Washington, USA
| | - Jeannine S. McCune
- Department of Population Sciences, City of Hope, Duarte, California, USA
| | - Nicholas H. Oberlies
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA.
| | - Nadja B. Cech
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA.
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Salehi B, Sharopov F, Boyunegmez Tumer T, Ozleyen A, Rodríguez-Pérez C, Ezzat SM, Azzini E, Hosseinabadi T, Butnariu M, Sarac I, Bostan C, Acharya K, Sen S, Nur Kasapoglu K, Daşkaya-Dikmen C, Özçelik B, Baghalpour N, Sharifi-Rad J, Valere Tsouh Fokou P, Cho WC, Martins N. Symphytum Species: A Comprehensive Review on Chemical Composition, Food Applications and Phytopharmacology. Molecules 2019; 24:2272. [PMID: 31216776 PMCID: PMC6631335 DOI: 10.3390/molecules24122272,] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 06/28/2023] Open
Abstract
Symphytum species belongs to the Boraginaceae family and have been used for centuries for bone breakages, sprains and rheumatism, liver problems, gastritis, ulcers, skin problems, joint pain and contusions, wounds, gout, hematomas and thrombophlebitis. Considering the innumerable potentialities of the Symphytum species and their widespread use in the world, it is extremely important to provide data compiling the available literature to identify the areas of intense research and the main gaps in order to design future studies. The present review aims at summarizing the main data on the therapeutic indications of the Symphytum species based on the current evidence, also emphasizing data on both the efficacy and adverse effects. The present review was carried out by consulting PubMed (Medline), Web of Science, Embase, Scopus, Cochrane Database, Science Direct and Google Scholar (as a search engine) databases to retrieve the most updated articles on this topic. All articles were carefully analyzed by the authors to assess their strengths and weaknesses, and to select the most useful ones for the purpose of review, prioritizing articles published from 1956 to 2018. The pharmacological effects of the Symphytum species are attributed to several chemical compounds, among them allantoin, phenolic compounds, glycopeptides, polysaccharides and some toxic pyrrolizidine alkaloids. Not less important to highlight are the risks associated with its use. In fact, there is increasing consumption of over-the-counter drugs, which when associated with conventional drugs can cause serious and even fatal adverse events. Although clinical trials sustain the folk topical application of Symphytum species in musculoskeletal and blunt injuries, with minor adverse effects, its antimicrobial potency was still poorly investigated. Further studies are needed to assess the antimicrobial spectrum of Symphytum species and to characterize the active molecules both in vitro and in vivo.
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Affiliation(s)
- Bahare Salehi
- Student Research Committee, School of Medicine, Bam University of Medical Sciences, Bam 44340847, Iran.
| | - Farukh Sharopov
- Department of Pharmaceutical Technology, Avicenna Tajik State Medical University, Rudaki 139, Dushanbe 734003, Tajikistan.
| | - Tugba Boyunegmez Tumer
- Department of Molecular Biology and Genetics, Faculty of Arts and Science, Canakkale Onsekiz Mart University, Canakkale 17020, Turkey.
| | - Adem Ozleyen
- Graduate Program of Biomolecular Sciences, Institute of Natural and Applied Sciences, Canakkale Onsekiz Mart University, Canakkale 17020, Turkey.
| | - Celia Rodríguez-Pérez
- Department of Nutrition and Food Science, University of Granada, Campus of Cartuja, E-18071 Granada, Spain.
- Institute of Nutrition and Food Technology (INYTA) 'José Mataix', Biomedical Research Centre, University of Granada, Avenida del Conocimiento s/n, E-18071 Granada, Spain.
| | - Shahira M Ezzat
- Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El-Ainy Street, Cairo 11562, Egypt.
- Department of Pharmacognosy, Faculty of Pharmacy, October University for Modern Science and Arts (MSA), 6th October City 12566, Egypt.
| | - Elena Azzini
- Centre for Research on Food and Nutrition, Council for Agricultural Research and Economics, Rome 546-00178 , Italy.
| | - Tahereh Hosseinabadi
- Department of Pharmacognosy and Biotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran.
| | - Monica Butnariu
- Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara, 300645 Calea Aradului 119, Timis, Romania.
| | - Ioan Sarac
- Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara, 300645 Calea Aradului 119, Timis, Romania.
| | - Cristian Bostan
- Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara, 300645 Calea Aradului 119, Timis, Romania.
| | - Krishnendu Acharya
- Molecular and Applied Mycology and Plant Pathology Laboratory, Department of Botany, University of Calcutta, Kolkata 700019, India.
| | - Surjit Sen
- Molecular and Applied Mycology and Plant Pathology Laboratory, Department of Botany, University of Calcutta, Kolkata 700019, India.
- Department of Botany, Fakir Chand College, Diamond Harbour, West Bengal 743331, India.
| | - Kadriye Nur Kasapoglu
- Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Food Engineering Department, Ayazağa Campus, Maslak 34469, Istanbul, Turkey.
| | - Ceren Daşkaya-Dikmen
- Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Food Engineering Department, Ayazağa Campus, Maslak 34469, Istanbul, Turkey.
- Istanbul Gedik University, Department of Gastronomy and Culinary Arts, 34876 Kartal, Istanbul, Turkey.
| | - Beraat Özçelik
- Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Food Engineering Department, Ayazağa Campus, Maslak 34469, Istanbul, Turkey.
- Bioactive Research & Innovation Food Manufac. Indust. Trade Ltd., Katar Street, Teknokent ARI-3, B110, Sarıyer 34467, Istanbul, Turkey.
| | - Navid Baghalpour
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran.
| | - Javad Sharifi-Rad
- Zabol Medicinal Plants Research Center, Zabol University of Medical Sciences, Zabol 61615-585, Iran.
| | - Patrick Valere Tsouh Fokou
- Antimicrobial and Biocontrol Agents Unit, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Ngoa Ekelle, Annex Fac. Sci, Yaounde 812, Cameroon.
| | - William C Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, 30 Gascoigne Road, Hong Kong, China.
| | - Natália Martins
- Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
- Institute for Research and Innovation in Health (i3S), University of Porto, 4200-135 Porto, Portugal.
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Salehi B, Sharopov F, Boyunegmez Tumer T, Ozleyen A, Rodríguez-Pérez C, Ezzat SM, Azzini E, Hosseinabadi T, Butnariu M, Sarac I, Bostan C, Acharya K, Sen S, Nur Kasapoglu K, Daşkaya-Dikmen C, Özçelik B, Baghalpour N, Sharifi-Rad J, Valere Tsouh Fokou P, Cho WC, Martins N. Symphytum Species: A Comprehensive Review on Chemical Composition, Food Applications and Phytopharmacology. Molecules 2019; 24:E2272. [PMID: 31216776 PMCID: PMC6631335 DOI: 10.3390/molecules24122272] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/05/2019] [Accepted: 06/11/2019] [Indexed: 12/20/2022] Open
Abstract
Symphytum species belongs to the Boraginaceae family and have been used for centuries for bone breakages, sprains and rheumatism, liver problems, gastritis, ulcers, skin problems, joint pain and contusions, wounds, gout, hematomas and thrombophlebitis. Considering the innumerable potentialities of the Symphytum species and their widespread use in the world, it is extremely important to provide data compiling the available literature to identify the areas of intense research and the main gaps in order to design future studies. The present review aims at summarizing the main data on the therapeutic indications of the Symphytum species based on the current evidence, also emphasizing data on both the efficacy and adverse effects. The present review was carried out by consulting PubMed (Medline), Web of Science, Embase, Scopus, Cochrane Database, Science Direct and Google Scholar (as a search engine) databases to retrieve the most updated articles on this topic. All articles were carefully analyzed by the authors to assess their strengths and weaknesses, and to select the most useful ones for the purpose of review, prioritizing articles published from 1956 to 2018. The pharmacological effects of the Symphytum species are attributed to several chemical compounds, among them allantoin, phenolic compounds, glycopeptides, polysaccharides and some toxic pyrrolizidine alkaloids. Not less important to highlight are the risks associated with its use. In fact, there is increasing consumption of over-the-counter drugs, which when associated with conventional drugs can cause serious and even fatal adverse events. Although clinical trials sustain the folk topical application of Symphytum species in musculoskeletal and blunt injuries, with minor adverse effects, its antimicrobial potency was still poorly investigated. Further studies are needed to assess the antimicrobial spectrum of Symphytum species and to characterize the active molecules both in vitro and in vivo.
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Affiliation(s)
- Bahare Salehi
- Student Research Committee, School of Medicine, Bam University of Medical Sciences, Bam 44340847, Iran.
| | - Farukh Sharopov
- Department of Pharmaceutical Technology, Avicenna Tajik State Medical University, Rudaki 139, Dushanbe 734003, Tajikistan.
| | - Tugba Boyunegmez Tumer
- Department of Molecular Biology and Genetics, Faculty of Arts and Science, Canakkale Onsekiz Mart University, Canakkale 17020, Turkey.
| | - Adem Ozleyen
- Graduate Program of Biomolecular Sciences, Institute of Natural and Applied Sciences, Canakkale Onsekiz Mart University, Canakkale 17020, Turkey.
| | - Celia Rodríguez-Pérez
- Department of Nutrition and Food Science, University of Granada, Campus of Cartuja, E-18071 Granada, Spain.
- Institute of Nutrition and Food Technology (INYTA) 'José Mataix', Biomedical Research Centre, University of Granada, Avenida del Conocimiento s/n, E-18071 Granada, Spain.
| | - Shahira M Ezzat
- Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El-Ainy Street, Cairo 11562, Egypt.
- Department of Pharmacognosy, Faculty of Pharmacy, October University for Modern Science and Arts (MSA), 6th October City 12566, Egypt.
| | - Elena Azzini
- Centre for Research on Food and Nutrition, Council for Agricultural Research and Economics, Rome 546-00178 , Italy.
| | - Tahereh Hosseinabadi
- Department of Pharmacognosy and Biotechnology, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran.
| | - Monica Butnariu
- Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara, 300645 Calea Aradului 119, Timis, Romania.
| | - Ioan Sarac
- Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara, 300645 Calea Aradului 119, Timis, Romania.
| | - Cristian Bostan
- Banat's University of Agricultural Sciences and Veterinary Medicine "King Michael I of Romania" from Timisoara, 300645 Calea Aradului 119, Timis, Romania.
| | - Krishnendu Acharya
- Molecular and Applied Mycology and Plant Pathology Laboratory, Department of Botany, University of Calcutta, Kolkata 700019, India.
| | - Surjit Sen
- Molecular and Applied Mycology and Plant Pathology Laboratory, Department of Botany, University of Calcutta, Kolkata 700019, India.
- Department of Botany, Fakir Chand College, Diamond Harbour, West Bengal 743331, India.
| | - Kadriye Nur Kasapoglu
- Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Food Engineering Department, Ayazağa Campus, Maslak 34469, Istanbul, Turkey.
| | - Ceren Daşkaya-Dikmen
- Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Food Engineering Department, Ayazağa Campus, Maslak 34469, Istanbul, Turkey.
- Istanbul Gedik University, Department of Gastronomy and Culinary Arts, 34876 Kartal, Istanbul, Turkey.
| | - Beraat Özçelik
- Istanbul Technical University, Chemical and Metallurgical Engineering Faculty, Food Engineering Department, Ayazağa Campus, Maslak 34469, Istanbul, Turkey.
- Bioactive Research & Innovation Food Manufac. Indust. Trade Ltd., Katar Street, Teknokent ARI-3, B110, Sarıyer 34467, Istanbul, Turkey.
| | - Navid Baghalpour
- Phytochemistry Research Center, Shahid Beheshti University of Medical Sciences, Tehran 11369, Iran.
| | - Javad Sharifi-Rad
- Zabol Medicinal Plants Research Center, Zabol University of Medical Sciences, Zabol 61615-585, Iran.
| | - Patrick Valere Tsouh Fokou
- Antimicrobial and Biocontrol Agents Unit, Department of Biochemistry, Faculty of Science, University of Yaounde 1, Ngoa Ekelle, Annex Fac. Sci, Yaounde 812, Cameroon.
| | - William C Cho
- Department of Clinical Oncology, Queen Elizabeth Hospital, 30 Gascoigne Road, Hong Kong, China.
| | - Natália Martins
- Faculty of Medicine, University of Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
- Institute for Research and Innovation in Health (i3S), University of Porto, 4200-135 Porto, Portugal.
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Colegate SM, Gardner DR, Betz JM, Panter KE. Semi-automated separation of the epimeric dehydropyrrolizidine alkaloids lycopsamine and intermedine: preparation of their N-oxides and NMR comparison with diastereoisomeric rinderine and echinatine. PHYTOCHEMICAL ANALYSIS : PCA 2014; 25:429-438. [PMID: 24816769 DOI: 10.1002/pca.2511] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2013] [Revised: 01/29/2014] [Accepted: 02/02/2014] [Indexed: 06/03/2023]
Abstract
INTRODUCTION The diversity of structure and, particularly, stereochemical variation of the dehydropyrrolizidine alkaloids can present challenges for analysis and the isolation of pure compounds for the preparation of analytical standards and for toxicology studies. OBJECTIVE To investigate methods for the separation of gram-scale quantities of the epimeric dehydropyrrolizidine alkaloids lycopsamine and intermedine and to compare their NMR spectroscopic data with those of their heliotridine-based analogues echinatine and rinderine. METHODS Lycopsamine and intermedine were extracted, predominantly as their N-oxides and along with their acetylated derivatives, from commercial samples of comfrey (Symphytum officinale) root. Alkaloid enrichment involved liquid-liquid partitioning of the crude methanol extract between dilute aqueous acid and n-butanol, reduction of N-oxides and subsequent continuous liquid-liquid extraction of free base alkaloids into CHCl3 . The alkaloid-rich fraction was further subjected to semi-automated flash chromatography using boronated soda glass beads or boronated quartz sand. RESULTS Boronated soda glass beads (or quartz sand) chromatography adapted to a Biotage Isolera Flash Chromatography System enabled large-scale separation (at least up to 1-2 g quantities) of lycopsamine and intermedine. The structures were confirmed using one- and two-dimensional (1) H- and (13) C-NMR spectroscopy. Examination of the NMR data for lycopsamine, intermedine and their heliotridine-based analogues echinatine and rinderine allowed for some amendments of literature data and provided useful comparisons for determining relative configurations in monoester dehydropyrrolizidine alkaloids. A similar NMR comparison of lycopsamine and intermedine with their N-oxides showed the effects of N-oxidation on some key chemical shifts. A levorotatory shift in specific rotation from +3.29° to -1.5° was observed for lycopsamine when dissolved in ethanol or methanol respectively. CONCLUSION A semi-automated flash chromatographic process using boronated soda glass beads was standardised and confirmed as a useful, larger scale preparative approach for separating the epimers lycopsamine and intermedine. The useful NMR correlations to stereochemical arrangements within this specific class of dehydropyrrolizidine alkaloid cannot be confidently extrapolated to other similar dehydropyrrolizidine alkaloids. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
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Affiliation(s)
- Steven M Colegate
- Poisonous Plant Research Laboratory, Agriculture Research Service, US Department of Agriculture, 1150 East 1400 North, Logan, Utah, 84341, USA
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Mei N, Guo L, Fu PP, Fuscoe JC, Luan Y, Chen T. Metabolism, genotoxicity, and carcinogenicity of comfrey. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2010; 13:509-26. [PMID: 21170807 PMCID: PMC5894094 DOI: 10.1080/10937404.2010.509013] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Comfrey has been consumed by humans as a vegetable and a tea and used as an herbal medicine for more than 2000 years. Comfrey, however, produces hepatotoxicity in livestock and humans and carcinogenicity in experimental animals. Comfrey contains as many as 14 pyrrolizidine alkaloids (PA), including 7-acetylintermedine, 7-acetyllycopsamine, echimidine, intermedine, lasiocarpine, lycopsamine, myoscorpine, symlandine, symphytine, and symviridine. The mechanisms underlying comfrey-induced genotoxicity and carcinogenicity are still not fully understood. The available evidence suggests that the active metabolites of PA in comfrey interact with DNA in liver endothelial cells and hepatocytes, resulting in DNA damage, mutation induction, and cancer development. Genotoxicities attributed to comfrey and riddelliine (a representative genotoxic PA and a proven rodent mutagen and carcinogen) are discussed in this review. Both of these compounds induced similar profiles of 6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP)-derived DNA adducts and similar mutation spectra. Further, the two agents share common mechanisms of drug metabolism and carcinogenesis. Overall, comfrey is mutagenic in liver, and PA contained in comfrey appear to be responsible for comfrey-induced toxicity and tumor induction.
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Affiliation(s)
- Nan Mei
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, Arkansas 72079, USA.
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Gomes MFPL, de Oliveira Massoco C, Xavier JG, Bonamin LV. Comfrey (Symphytum Officinale. l.) and Experimental Hepatic Carcinogenesis: A Short-term Carcinogenesis Model Study. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2010; 7:197-202. [PMID: 18955295 PMCID: PMC2862927 DOI: 10.1093/ecam/nem172] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2005] [Accepted: 09/25/2007] [Indexed: 02/05/2023]
Abstract
Comfrey or Symphytum officinale (L.) (Boraginaceae) is a very popular plant used for therapeutic purposes. Since the 1980s, its effects have been studied in long-term carcinogenesis studies, in which Comfrey extract is administered at high doses during several months and the neoplastic hepatic lesions are evaluated. However, the literature on this topic is very poor considering the studies performed under short-term carcinogenesis protocols, such as the 'resistant hepatocyte model' (RHM). In these studies, it is possible to observe easily the phenomena related to the early phases of tumor development, since pre-neoplastic lesions (PNLs) rise in about 1-2 months of chemical induction. Herein, the effects of chronic oral treatment of rats with 10% Comfrey ethanolic extract were evaluated in a RHM. Wistar rats were sequentially treated with N-nitrosodiethylamine (ip) and 2-acetilaminofluorene (po), and submitted to hepatectomy to induce carcinogenesis promotion. Macroscopic/microscopic quantitative analysis of PNL was performed. Non-parametric statistical tests (Mann-Whitney and χ(2)) were used, and the level of significance was set at P ≤ 0.05. Comfrey treatment reduced the number of pre-neoplastic macroscopic lesions up to 1 mm (P ≤ 0.05), the percentage of oval cells (P = 0.0001) and mitotic figures (P = 0.007), as well as the number of Proliferating Cell Nuclear Antigen (PCNA) positive cells (P = 0.0001) and acidophilic pre-neoplastic nodules (P = 0.05). On the other hand, the percentage of cells presenting megalocytosis (P = 0.0001) and vacuolar degeneration (P = 0.0001) was increased. Scores of fibrosis, glycogen stores and the number of nucleolus organizing regions were not altered. The study indicated that oral treatment of rats with 10% Comfrey alcoholic extract reduced cell proliferation in this model.
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Affiliation(s)
- Maria Fernanda Pereira Lavieri Gomes
- Laboratory of Veterinary Pathology, Faculty of Veterinary Medicine, University of Santo Amaro, Oncocell biotecnologia LTDA and Laboratory of Pathology, Health Sciences Institute, University Paulista, São Paulo, Brazil
| | - Cristina de Oliveira Massoco
- Laboratory of Veterinary Pathology, Faculty of Veterinary Medicine, University of Santo Amaro, Oncocell biotecnologia LTDA and Laboratory of Pathology, Health Sciences Institute, University Paulista, São Paulo, Brazil
| | - José Guilherme Xavier
- Laboratory of Veterinary Pathology, Faculty of Veterinary Medicine, University of Santo Amaro, Oncocell biotecnologia LTDA and Laboratory of Pathology, Health Sciences Institute, University Paulista, São Paulo, Brazil
| | - Leoni Villano Bonamin
- Laboratory of Veterinary Pathology, Faculty of Veterinary Medicine, University of Santo Amaro, Oncocell biotecnologia LTDA and Laboratory of Pathology, Health Sciences Institute, University Paulista, São Paulo, Brazil
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Brantley SJ, Oberlies NH, Kroll DJ, Paine MF. Two flavonolignans from milk thistle (Silybum marianum) inhibit CYP2C9-mediated warfarin metabolism at clinically achievable concentrations. J Pharmacol Exp Ther 2010; 332:1081-7. [PMID: 19934397 PMCID: PMC2835426 DOI: 10.1124/jpet.109.161927] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Accepted: 11/23/2009] [Indexed: 12/20/2022] Open
Abstract
Milk thistle (Silybum marianum) is a popular herbal product used for hepatoprotection and chemoprevention. Two commercially available formulations are the crude extract, silymarin, and the semipurified product, silibinin. Silymarin consists of at least seven flavonolignans, of which the most prevalent are the diastereoisomers silybin A and silybin B; silibinin consists only of silybin A and silybin B. Based on a recent clinical study showing an interaction between a silymarin product and the CYP2C9 substrate losartan, the CYP2C9 inhibition properties of silybin A and silybin B and corresponding regioisomers, isosilybin A and isosilybin B, were evaluated using human liver microsomes (HLMs), recombinant CYP2C9 (rCYP2C9) enzymes, and the clinically relevant probe, (S)-warfarin. Silybin B was the most potent inhibitor in HLMs, followed by silybin A, isosilybin B, and isosilybin A (IC(50) of 8.2, 18, 74, and >100 microM, respectively). Next, silybin A and silybin B were selected for further characterization. As with HLMs, silybin B was more potent than silybin A toward rCYP2C9 1 (6.7 versus 12 microM), rCYP2C9 2 (9.3 versus 19 microM), and rCYP2C9 3 (2.4 versus 9.3 microM). Using a matrix of five substrate (1-15 microM) and six inhibitor (1-80 microM) concentrations and HLMs, both diastereoisomers inhibited (S)-warfarin 7-hydroxylation in a manner described best by a mixed-type inhibition model (K(i) values of 4.8 and 10 microM for silybin B and silybin A, respectively). These observations, combined with the high systemic silibinin concentrations (>5-75 microM) achieved in a phase I study involving prostate cancer patients, prompt clinical evaluation of a potential warfarin-milk thistle interaction.
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Affiliation(s)
- Scott J Brantley
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina, Chapel Hill, NC 27599-7569, USA
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Crews C, Berthiller F, Krska R. Update on analytical methods for toxic pyrrolizidine alkaloids. Anal Bioanal Chem 2009; 396:327-38. [DOI: 10.1007/s00216-009-3092-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2009] [Revised: 08/20/2009] [Accepted: 08/21/2009] [Indexed: 10/20/2022]
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Alali FQ, Tahboub YR, Ibrahim ES, Qandil AM, Tawaha K, Burgess JP, Sy A, Nakanishi Y, Kroll DJ, Oberlies NH. Pyrrolizidine alkaloids from Echium glomeratum (Boraginaceae). PHYTOCHEMISTRY 2008; 69:2341-2346. [PMID: 18691727 DOI: 10.1016/j.phytochem.2008.06.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Revised: 06/26/2008] [Accepted: 06/27/2008] [Indexed: 05/26/2023]
Abstract
The methanolic extract of the whole plant of Echium glomeratum Poir. (Boraginaceae) has afforded five pyrrolizidine alkaloids, three that were (7S, 8R)-petranine (1), (7S, 8S)-petranine (2), and (7R, 8R)-petranine (3a) or (7R, 8S)-petranine (3b), comprising a tricyclic pyrrolizidine alkaloids subclass; and two that were known but to the species: 7-angeloylretronecine (4) and 9-angeloylretronecine (5). All compounds were tested against a human tumor panel for cytotoxicity; no activity was observed (EC50 values>20microg/ml).
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Affiliation(s)
- Feras Q Alali
- Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan.
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Guo L, Mei N, Dial S, Fuscoe J, Chen T. Comparison of gene expression profiles altered by comfrey and riddelliine in rat liver. BMC Bioinformatics 2007; 8 Suppl 7:S22. [PMID: 18047722 PMCID: PMC2099491 DOI: 10.1186/1471-2105-8-s7-s22] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Background Comfrey (Symphytum officinale) is a perennial plant and has been consumed by humans as a vegetable, a tea and an herbal medicine for more than 2000 years. It, however, is hepatotoxic and carcinogenic in experimental animals and hepatotoxic in humans. Pyrrolizidine alkaloids (PAs) exist in many plants and many of them cause liver toxicity and/or cancer in humans and experimental animals. In our previous study, we found that the mutagenicity of comfrey was associated with the PAs contained in the plant. Therefore, we suggest that carcinogenicity of comfrey result from those PAs. To confirm our hypothesis, we compared the expression of genes and processes of biological functions that were altered by comfrey (mixture of the plant with PAs) and riddelliine (a prototype of carcinogenic PA) in rat liver for carcinogenesis in this study. Results Groups of 6 Big Blue Fisher 344 rats were treated with riddelliine at 1 mg/kg body weight by gavage five times a week for 12 weeks or fed a diet containing 8% comfrey root for 12 weeks. Animals were sacrificed one day after the last treatment and the livers were isolated for gene expression analysis. The gene expressions were investigated using Applied Biosystems Rat Whole Genome Survey Microarrays and the biological functions were analyzed with Ingenuity Analysis Pathway software. Although there were large differences between the significant genes and between the biological processes that were altered by comfrey and riddelliine, there were a number of common genes and function processes that were related to carcinogenesis. There was a strong correlation between the two treatments for fold-change alterations in expression of drug metabolizing and cancer-related genes. Conclusion Our results suggest that the carcinogenesis-related gene expression patterns resulting from the treatments of comfrey and riddelliine are very similar, and PAs contained in comfrey are the main active components responsible for carcinogenicity of the plant.
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Affiliation(s)
- Lei Guo
- Division of Systems Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA.
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Oberlies NH, Kim NC, Brine DR, Collins BJ, Handy RW, Sparacino CM, Wani MC, Wall ME. Analysis of herbal teas made from the leaves of comfrey (Symphytum officinale): reduction of N-oxides results in order of magnitude increases in the measurable concentration of pyrrolizidine alkaloids. Public Health Nutr 2007; 7:919-24. [PMID: 15482618 DOI: 10.1079/phn2004624] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
AbstractObjectives:To determine the relative quantities of two hepatotoxic pyrrolizidine alkaloids, symphytine and echimidine, in teas prepared from comfrey leaves (Symphytum officinale), and to determine the potential contribution of the N-oxide forms of these alkaloids to levels of the parent alkaloids.Design:Comfrey leaves were purchased from three commercial sources and used to prepare tea in a manner consistent with the methods used by consumers. An extraction scheme was devised for extraction of the alkaloids, and a gas chromatographic method was developed to quantify the two major alkaloids, symphytine and echimidine. Recognising that the N-oxide derivatives of these alkaloids have also been identified in comfrey preparations, chemical reduction was applied to determine the total quantities of the alkaloids as free bases and as N-oxide derivatives.Results:The concentration of symphytine and echimidine varied considerably between teas prepared from leaves purchased from the different vendors of plant material. Moreover, a much higher concentration of symphytine was found in the tea when steps were included to reduce N-oxides prior to analysis. The treatment of pure symphytine with hot water did not generate the N-oxide derivative de novo.Conclusions:Since the pyrrolizidine alkaloids are known to be hepatotoxic, consumption of herbal teas made from comfrey leaves may be ill-advised. The concentration of pyrrolizidine alkaloids in such teas may be underestimated substantially unless the concentration of N-oxides is taken into consideration.
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Affiliation(s)
- Nicholas H Oberlies
- Natural Products Laboratory, RTI International, Research Triangle Park, NC 27709, USA.
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Mei N, Guo L, Zhang L, Shi L, Sun YA, Fung C, Moland CL, Dial SL, Fuscoe JC, Chen T. Analysis of gene expression changes in relation to toxicity and tumorigenesis in the livers of Big Blue transgenic rats fed comfrey (Symphytum officinale). BMC Bioinformatics 2006; 7 Suppl 2:S16. [PMID: 17118137 PMCID: PMC1683566 DOI: 10.1186/1471-2105-7-s2-s16] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Background Comfrey is consumed by humans as a vegetable and a tea, and has been used as an herbal medicine for more than 2000 years. Comfrey, however, is hepatotoxic in livestock and humans and carcinogenic in experimental animals. Our previous study suggested that comfrey induces liver tumors by a genotoxic mechanism and that the pyrrolizidine alkaloids in the plant are responsible for mutation induction and tumor initiation in rat liver. Results In this study, we identified comfrey-induced gene expression profile in the livers of rats. Groups of 6 male transgenic Big Blue rats were fed a basal diet and a diet containing 8% comfrey roots, a dose that resulted in liver tumors in a previous carcinogenicity bioassay. The animals were treated for 12 weeks and sacrificed one day after the final treatment. We used a rat microarray containing 26,857 genes to perform genome-wide gene expression studies. Dietary comfrey resulted in marked changes in liver gene expression, as well as in significant decreases in the body weight and increases in liver mutant frequency. When a two-fold cutoff value and a P-value less than 0.01 were selected, 2,726 genes were identified as differentially expressed in comfrey-fed rats compared to control animals. Among these genes, there were 1,617 genes associated by Ingenuity Pathway Analysis with particular functions, and the differentially expressed genes in comfrey-fed rat livers were involved in metabolism, injury of endothelial cells, and liver injury and abnormalities, including liver fibrosis and cancer development. Conclusion The gene expression profile provides us a better understanding of underlying mechanisms for comfrey-induced hepatic toxicity. Integration of gene expression changes with known pathological changes can be used to formulate a mechanistic scheme for comfrey-induced liver toxicity and tumorigenesis.
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Affiliation(s)
- Nan Mei
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA
| | - Lei Guo
- Division of Systems Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA
| | - Lu Zhang
- Molecular Biology-SDS/Arrays, Applied Biosystems, Foster City, CA 94404, USA
- Solexa, Inc., 25861 Industrial Boulevard, Hayward, CA 94545, USA
| | - Leming Shi
- Division of Systems Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA
| | - Yongming Andrew Sun
- Molecular Biology-SDS/Arrays, Applied Biosystems, Foster City, CA 94404, USA
| | - Chris Fung
- Molecular Biology-SDS/Arrays, Applied Biosystems, Foster City, CA 94404, USA
| | - Carrie L Moland
- Division of Systems Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA
| | - Stacey L Dial
- Division of Systems Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA
| | - James C Fuscoe
- Division of Systems Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA
| | - Tao Chen
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, FDA, Jefferson, AR 72079, USA
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Mei N, Guo L, Fu PP, Heflich RH, Chen T. Mutagenicity of comfrey (Symphytum Officinale) in rat liver. Br J Cancer 2005; 92:873-5. [PMID: 15726100 PMCID: PMC2361893 DOI: 10.1038/sj.bjc.6602420] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Comfrey is a rat liver toxin and carcinogen that has been used as a vegetable and herbal remedy by humans. In order to evaluate the mechanisms underlying its carcinogenicity, we examined the mutagenicity of comfrey in the transgenic Big Blue rat model. Our results indicate that comfrey is mutagenic in rat liver and the types of mutations induced by comfrey suggest that its tumorigenicity results from the genotoxicity of pyrrolizidine alkaloids in the plant.
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Affiliation(s)
- N Mei
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, US Food and Drug Administration, HFT-130, 3900 NCTR Road, Jefferson, AR 72079, USA
| | - L Guo
- Center for Hepatotoxicology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - P P Fu
- Division of Biochemical Toxicology, National Center for Toxicological Research, US Food and Drug Administration, Jefferson, AR 72079, USA
| | - R H Heflich
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, US Food and Drug Administration, HFT-130, 3900 NCTR Road, Jefferson, AR 72079, USA
| | - T Chen
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, US Food and Drug Administration, HFT-130, 3900 NCTR Road, Jefferson, AR 72079, USA
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, US Food and Drug Administration, HFT-130, 3900 NCTR Road, Jefferson, AR 72079, USA. E-mail:
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Current awareness in phytochemical analysis. PHYTOCHEMICAL ANALYSIS : PCA 2001; 12:286-291. [PMID: 11708301 DOI: 10.1002/pca.556] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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