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Bakun P, Mlynarczyk DT, Koczorowski T, Cerbin-Koczorowska M, Piwowarczyk L, Kolasiński E, Stawny M, Kuźmińska J, Jelińska A, Goslinski T. Tea-break with epigallocatechin gallate derivatives - Powerful polyphenols of great potential for medicine. Eur J Med Chem 2023; 261:115820. [PMID: 37776575 DOI: 10.1016/j.ejmech.2023.115820] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 09/09/2023] [Accepted: 09/12/2023] [Indexed: 10/02/2023]
Abstract
Epigallocatechin gallate (EGCG) is a polyphenol present in green tea (Camellia sinensis), which has revealed anti-cancer effects toward a variety of cancer cells in vitro and protective potential against neurodegenerative diseases such as Alzheimer's and Parkinson's. Unfortunately, EGCG presents disappointing bioavailability after oral administration, primarily due to its chemical instability and poor absorption. Due to these limitations, EGCG is currently not used in medication, but only as a dietary supplement in the form of green tea extract. Therefore, it needs further modifications before being considered suitable for extensive medical applications. In this article, we review the scientific literature about EGCG derivatives focusing on their biological properties and potential medical applications. The most common chemical modifications of epigallocatechin gallate rely on introducing fatty acid chains or sugar molecules to its chemical structure to modify solubility. Another frequently employed procedure is based on blocking EGCG's hydroxyl groups with various substituents. Novel derivatives reveal interesting properties, of which, antioxidant, anti-inflammatory, antitumor and antimicrobial, are especially important. It is worth noting that the most promising EGCG derivatives present higher stability and activity than base EGCG.
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Affiliation(s)
- Paweł Bakun
- Chair and Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland.
| | - Dariusz T Mlynarczyk
- Chair and Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland
| | - Tomasz Koczorowski
- Chair and Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland
| | - Magdalena Cerbin-Koczorowska
- Chair and Department of Medical Education, Poznan University of Medical Sciences, Rokietnicka 7, Poznań, 60-806, Poland; Edinburgh Medical School: Medical Education, University of Edinburgh, Chancellor's Building, EH16 4SB, Edinburgh, Scotland, United Kingdom
| | - Ludwika Piwowarczyk
- Chair and Department of Pharmaceutical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland
| | - Emil Kolasiński
- Chair and Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland
| | - Maciej Stawny
- Chair and Department of Pharmaceutical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland
| | - Joanna Kuźmińska
- Chair and Department of Pharmaceutical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland
| | - Anna Jelińska
- Chair and Department of Pharmaceutical Chemistry, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland
| | - Tomasz Goslinski
- Chair and Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, Poznań, 60-780, Poland.
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Mechanism of (−)-epigallocatechin gallate (EGCG) dimerization by low-temperature plasma. Sci Rep 2022; 12:15396. [PMID: 36100688 PMCID: PMC9470551 DOI: 10.1038/s41598-022-19806-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 09/05/2022] [Indexed: 11/12/2022] Open
Abstract
The efficient dimerization of (−)-Epigallocatechin gallate (EGCG), which is the major bioactive constituent isolated from the leaves of Camellia sinensis, was initially reported without changes in its stereochemistry using low-temperature plasma. The contribution of plasma during the dimerization of EGCG in a methanolic solution was quantified using a major factor, with the major factor demonstrated based on the contents of newly generated products, in this case the sum of oolonghomobisflavans A and B depending on the plasma treatment method. Samples were treated in three methods: plasma direct treatment, an indirect treatment using only reactive species, and an indirect treatment using effects other than those by reactive species. Ozone was identified as a major factor during the plasma treatment, and the operating ranges of the ozone concentration for regulated dimerization were evaluated. The mechanism by which EGCG synthesizes dimers A and B during the treatment process using low-temperature plasma was investigated using the derived major factor and prior literature. The ozone generated by the plasma reacted with methanol to form formaldehyde, and dimers A and B were synthesized by oligomers through a methylene-bridge by the formaldehyde. A plausible pathway of regulated dimerization was deduced based on these results, and the mechanism of EGCG dimerization by plasma is described using this pathway.
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Mehmood S, Maqsood M, Mahtab N, Khan MI, Sahar A, Zaib S, Gul S. Epigallocatechin gallate: Phytochemistry, bioavailability, utilization challenges, and strategies. J Food Biochem 2022; 46:e14189. [PMID: 35474461 DOI: 10.1111/jfbc.14189] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/05/2022] [Accepted: 03/29/2022] [Indexed: 12/17/2022]
Abstract
Epigallocatechin gallate (EGCG), a green tea catechin, has gained the attention of current study due to its excellent health-promoting effects. It possesses anti-obesity, antimicrobial, anticancer, anti-inflammatory activities, and is under extensive investigation in functional foods for improvement. It is susceptible to lower stability, lesser bioavailability, and lower absorption rate due to various environmental, processing, formulations, and gastrointestinal conditions of the human body. Therefore, it is the foremost concern for the researchers to enhance its bioactivity and make it the most suitable therapeutic compound for its clinical applications. In the current review, factors affecting the bioavailability of EGCG and the possible strategies to overcome these issues are reviewed and discussed. This review summarizes structural modifications and delivery through nanoparticle-based approaches including nano-emulsions, encapsulations, and silica-based nanoparticles for effective use of EGCG in functional foods. Moreover, recent advances to enhance EGCG therapeutic efficacy by specifically targeting its molecules to increase its bioavailability and stability are also described. PRACTICAL APPLICATIONS: The main green tea constituent EGCG possesses several health-promoting effects making EGCG a potential therapeutic compound to cure ailments. However, its low stability and bioavailability render its uses in many disorders. Synthesizing EGCG prodrugs by structural modifications helps against its low bioavailability and stability by overcoming premature degradation and lower absorption rate. This review paper summarizes various strategies that benefit EGCG under different physiological conditions. The esterification, nanoparticle approaches, silica-based EGCG-NPs, and EGCG formulations serve as ideal EGCG modification strategies to deliver superior concentrations with lesser toxicity for its efficient penetration and absorption across cells both in vitro and in vivo. As a result of EGCG modifications, its bioactivities would be highly improved at lower doses. The protected or modified EGCG molecule would have enhanced potential effects and stability that would contribute to the clinical applications and expand its use in various food and cosmetic industries.
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Affiliation(s)
- Shomaila Mehmood
- Anhui Key Laboratory of Modern Biomanufacturing, School of Life Sciences, Anhui University, Hefei, P. R. China
| | - Maria Maqsood
- National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan
| | - Nazia Mahtab
- School of Resources and Environmental Engineering, Anhui University, Hefei, P. R. China
| | - Muhammad Issa Khan
- National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan
| | - Amna Sahar
- Department of Food Engineering, University of Agriculture, Faisalabad, Pakistan
| | - Sania Zaib
- Department of Biochemistry, Quaid-i-Azam University, Islamabad, Pakistan
| | - Shehla Gul
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad, Pakistan
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Rampino A, Annese T, Margari A, Tamma R, Ribatti D. Nutraceuticals and their role in tumor angiogenesis. Exp Cell Res 2021; 408:112859. [PMID: 34637764 DOI: 10.1016/j.yexcr.2021.112859] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/28/2021] [Accepted: 10/02/2021] [Indexed: 01/15/2023]
Abstract
Angiogenesis plays a pivotal role in cancer initiation, maintenance, and progression. Diet may inhibit, retard or reverse these processes affecting angiogenesis (angioprevention). Nutraceuticals, such as omega-3 fatty acids, amino acids, proteins, vitamins, minerals, fibers, and phenolic compounds, improve health benefits as they are a source of bioactive compounds that, among other effects, can regulate angiogenesis. The literature concerning the pro-angiogenic and/or anti-angiogenic nutraceuticals and the possible activated pathways in cancer and other non-neoplastic diseases by in vivo and in vitro experiments are reviewed.
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Affiliation(s)
- Antonio Rampino
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Medical School, Bari, Italy
| | - Tiziana Annese
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Medical School, Bari, Italy
| | - Anna Margari
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Medical School, Bari, Italy
| | - Roberto Tamma
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Medical School, Bari, Italy
| | - Domenico Ribatti
- Department of Basic Medical Sciences, Neurosciences and Sensory Organs, University of Bari Medical School, Bari, Italy.
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Gallemit PEM, Yoodee S, Malaitad T, Thongboonkerd V. Epigallocatechin-3-gallate plays more predominant roles than caffeine for inducing actin-crosslinking, ubiquitin/proteasome activity and glycolysis, and suppressing angiogenesis features of human endothelial cells. Biomed Pharmacother 2021; 141:111837. [PMID: 34175818 DOI: 10.1016/j.biopha.2021.111837] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 06/13/2021] [Accepted: 06/14/2021] [Indexed: 01/06/2023] Open
Abstract
A recent expression proteomics study has reported changes in cellular proteome (set of proteins) of human endothelial cells (ECs) induced by caffeine and epigallocatechin-3-gallate (EGCG), the most abundant bioactive compounds in coffee and green tea, respectively. Although both common and differential changes were highlighted by bioinformatics prediction, no experimental validation was performed. Herein, we reanalyzed these proteome datasets and performed protein-protein interactions network analysis followed by functional investigations using various assays to address the relevance of such proteome changes in human ECs functions. Protein-protein interactions network analysis revealed actin-crosslink formation, ubiquitin-proteasome activity and glycolysis as the three main networks among those significantly altered proteins induced by caffeine and EGCG. The experimental data showed predominant increases of actin-crosslink formation, ubiquitin-proteasome activity, and glycolysis (as reflected by increased F-actin and β-actin, declined ubiquitinated proteins and increased intracellular ATP, respectively) in the EGCG-treated cells. Investigations on angiogenesis features revealed that EGCG predominantly reduced ECs proliferation, migration/invasion, endothelial tube formation (as determined by numbers of nodes/junctions and meshes), barrier function (as determined by levels of VE-cadherin, zonula occludens-1 (ZO-1) and transendothelial resistance (TER)), and angiopoietin-2 secretion. However, both caffeine and EGCG had no effects on matrix metalloproteinase-2 (MMP-2) secretion. These data indicate that EGCG exhibits more potent effects on human ECs functions to induce actin-crosslink, ubiquitin-proteasome activity and glycolysis, and to suppress angiogenesis processes that commonly occur in various diseases, particularly cancers.
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Affiliation(s)
| | - Sunisa Yoodee
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Thanyalak Malaitad
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Visith Thongboonkerd
- Medical Proteomics Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
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Oladimeji O, Akinyelu J, Daniels A, Singh M. Modified Gold Nanoparticles for Efficient Delivery of Betulinic Acid to Cancer Cell Mitochondria. Int J Mol Sci 2021; 22:ijms22105072. [PMID: 34064888 PMCID: PMC8150271 DOI: 10.3390/ijms22105072] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 04/26/2021] [Accepted: 04/28/2021] [Indexed: 02/07/2023] Open
Abstract
Advances in nanomedicine have seen the adaptation of nanoparticles (NPs) for subcellular delivery for enhanced therapeutic impact and reduced side effects. The pivotal role of the mitochondria in apoptosis and their potential as a target in cancers enables selective induction of cancer cell death. In this study, we examined the mitochondrial targeted delivery of betulinic acid (BA) by the mitochondriotropic TPP+-functionalized epigallocatechin gallate (EGCG)-capped gold NPs (AuNPs), comparing the impact of polyethylene glycol (PEG) and poly-L-lysine-graft-polyethylene glycol (PLL-g-PEG) copolymer on delivery efficacy. This included the assessment of their cellular uptake, mitochondrial localization and efficacy as therapeutic delivery platforms for BA in the human Caco-2, HeLa and MCF-7 cancer cell lines. These mitochondrial-targeted nanocomplexes demonstrated significant inhibition of cancer cell growth, with targeted nanocomplexes recording IC50 values in the range of 3.12–13.2 µM compared to that of the free BA (9.74–36.31 µM) in vitro, demonstrating the merit of mitochondrial targeting. Their mechanisms of action implicated high amplitude mitochondrial depolarization, caspases 3/7 activation, with an associated arrest at the G0/G1 phase of the cell cycle. This nano-delivery system is a potentially viable platform for mitochondrial-targeted delivery of BA and highlights mitochondrial targeting as an option in cancer therapy.
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Tafazoli A, Tafazoli Moghadam E. Camellia Sinensis Mouthwashes in Oral Care: a Systematic Review. JOURNAL OF DENTISTRY (SHIRAZ, IRAN) 2020; 21:249-262. [PMID: 33344675 PMCID: PMC7737926 DOI: 10.30476/dentjods.2020.83204.1045] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herbal products are increasingly growing in the oral care market. Some of the related herbal compounds in this field have considerable clinical evidence for use in mouthwashes in their background. Camellia sinensis or tea plant has attracted numerous researchers of dentistry and pharmaceutical sciences, in recent years, for its biologic and medicinal properties. The effects such as anti-septic, anti-oxidative, and anti-inflammatory activities have made this plant a suitable candidate for preparation of mouthwashes. In this systematic review, we tried to find, evaluate, and categorize the sparse evidence in medical literature about Camellia sinensis mouthwashes. We explored three scientific databases with keywords including tea, dental care, Camellia sinensis, and mouthwashes and found 69 relevant studies including 41 randomized controlled trials (RCTs), which are generally proposing anti-microbial, anti-plaque, and analgesic indications for these tea formulations. Considering the main trend in clinical evidence and favorable safety profile, Camellia sinensis products are able to act as antiseptic, anti-plaque, and anti-inflammatory agents and can be used as useful mouthwashes in the future clinical studies and practice.
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Affiliation(s)
- Ali Tafazoli
- Dept. Clinical Pharmacy, Faculty of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ehsan Tafazoli Moghadam
- Dept. of Orthodontics, School of Dentistry, Qazvin University of Medical Sciences, Qazvin, Iran
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Silva AM, Martins-Gomes C, Fangueiro JF, Andreani T, Souto EB. Comparison of antiproliferative effect of epigallocatechin gallate when loaded into cationic solid lipid nanoparticles against different cell lines. Pharm Dev Technol 2019; 24:1243-1249. [PMID: 31437118 DOI: 10.1080/10837450.2019.1658774] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Several therapeutic properties have been attributed to epigallocatechin gallate (EGCG), a phytopharmaceutical polyphenol with antioxidant and antiproliferative activity. EGCG is, however, very prone to oxidation in aqueous solutions which changes its bioactive properties. Its loading in nanoparticles has been proposed to reduce its degradation while increasing its in vivo efficacy. The aim of this study was to compare the antiproliferative effect of EGCG before and after its loading in solid lipid nanoparticles (SLNs), against five different cell lines (Caco-2, HepG2, MCF-7, SV-80 and Y-79). EGCG produced concentration- and time-dependent antiproliferative effect, with efficacy dependent on the cell line. The order of potency was: MCF-7>SV-80>HepG2>Y-79>Caco-2, for 24 h exposure (MCF-7 IC50=58.60 ± 3.29 µg/mL; Caco-2 IC50>500.00 µg/mL). To the best of our knowledge this is the first study reporting EGCG antiproliferative effect in SV-80 and Y-79 cells. DDAB-SLN physicochemical properties (size ∼134 nm; PI∼0.179; ZP ∼+28mV) were only slightly modified with EGCG loading (EGCG-DDAB-SLN: ∼144 nm; PI∼0.160; ZP ∼+26mV). EGCG loading in SLN, only slightly increases the EGCG antiproliferative effect in MCF-7 and SV-80 cells. SLN exhibited intrinsic toxicity, attributed to the surfactant used in its production. From the obtained results, the biocompatibility of blank SLN must be also considered when testing the efficacy of loaded phytopharmaceutics.
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Affiliation(s)
- Amélia M Silva
- Department of Biology and Environment, University of Trás-os Montes e Alto Douro (UTAD) , Vila Real , Portugal.,Centre for Research and Technology of Agro-Environmental and Biological Sciences (CITAB-UTAD) , Vila Real , Portugal
| | - Carlos Martins-Gomes
- Department of Biology and Environment, University of Trás-os Montes e Alto Douro (UTAD) , Vila Real , Portugal.,Centre for Research and Technology of Agro-Environmental and Biological Sciences (CITAB-UTAD) , Vila Real , Portugal
| | - Joana F Fangueiro
- Centre for Research and Technology of Agro-Environmental and Biological Sciences (CITAB-UTAD) , Vila Real , Portugal.,Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC) , Coimbra , Portugal
| | - Tatiana Andreani
- Department of Biology and Environment, University of Trás-os Montes e Alto Douro (UTAD) , Vila Real , Portugal.,Centre for Research and Technology of Agro-Environmental and Biological Sciences (CITAB-UTAD) , Vila Real , Portugal.,Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto (FCUP) , Porto , Portugal
| | - Eliana B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC) , Coimbra , Portugal.,CEB - Centre of Biological Engineering, University of Minho , Braga , Portugal
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Diniz C, Suliburska J, Ferreira IMPLVO. New insights into the antiangiogenic and proangiogenic properties of dietary polyphenols. Mol Nutr Food Res 2017; 61. [PMID: 27981783 DOI: 10.1002/mnfr.201600912] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/02/2016] [Accepted: 12/08/2016] [Indexed: 12/14/2022]
Abstract
Polyphenols can be found in natural products of plant origin, including vegetables, fruits, and beverages. A large number of these plant origin compounds are an integral part of the human diet and in the past decade evidence has shown their beneficial properties in human health, by acting in several cell signaling pathways. Among other beneficial effects, polyphenols have been associated with angiogenesis. Increasing evidence highlighting the ability of dietary polyphenols to influence angiogenesis by interfering with multiple signaling pathways is debated. Particular emphasis is given to the mechanisms that ultimately may induce the formation of capillary-like structures (by increasing endothelial cell proliferation, migration, and invasion) or, conversely, may inhibit the steps of angiogenesis leading to the inhibition/regress of vascular development. Dietary polyphenols can, therefore, be viewed as promising nutraceuticals but important aspects have still to be further investigated, to deep knowledge concerning their concentration-mediated effects, effect of specific polyphenols, and respective metabolites, to ensure their appropriate and effective usefulness as proangiogenic or antiangiogenic nutraceuticals.
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Affiliation(s)
- Carmen Diniz
- LAQV/REQUIMTE-Departamento de Ciências do Medicamento, Laboratório de Farmacologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Joanna Suliburska
- Department of Human Nutrition and Hygiene, Poznan University of Life Sciences, Poznan, Poland
| | - Isabel M P L V O Ferreira
- LAQV/REQUIMTE-Departamento de Ciências Químicas, Laboratório de Bromatologia e Hidrologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
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Asakawa T. Synthesis of Effective Food Constituents toward the Development of Chemical Biology Investigations. YAKUGAKU ZASSHI 2016; 136:1613-1621. [PMID: 27904095 DOI: 10.1248/yakushi.16-00204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This article describes the development of various probes and immunogens for chemical-biological investigations of food flavonoids. We accomplished a large (gram)-scale asymmetric synthesis of a key intermediate, 5-aminopentyl deoxy epigallocatechin-3-gallate (APDOEGCg; 3), an analogue of green tea polyphenol EGCg, in which the key step was cationic cyclization utilizing neighboring group participation of the gallate carbonyl group. The synthetic APDOEGCg (3) was efficiently converted to a fluorescent probe 18 and an immunogen 19 by utilizing the high reactivity of the amine functional group. We confirmed the usefulness of these probes for imaging studies and the generation of antibodies, respectively. We also describe the efficient synthesis of a positron emission tomography (PET) probe [11C]20 by incorporation of 11C into EGCg (1), for which synthetic 4″-Me-EGCg (20) was utilized as an authentic sample. Our synthetic strategy was also applied for the practical synthesis of nobiletin (21), a polymethoxylated flavone from citrus. Synthetic nobiletin was readily converted to various probes by selective demethylation and incorporation of fluorescein, biotin or 11C. These probes should be useful for a range of biological applications. Detailed examination of the mechanisms and further applications are in progress.
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Lewandowska U, Fichna J, Gorlach S. Enhancement of anticancer potential of polyphenols by covalent modifications. Biochem Pharmacol 2016; 109:1-13. [PMID: 26776305 DOI: 10.1016/j.bcp.2015.12.019] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 12/23/2015] [Indexed: 12/23/2022]
Abstract
As evidenced by a growing number of respective clinical trials, a promising and increasingly valued approach to cancer prevention is chemoprevention which is based on using synthetic, semisynthetic, or natural compounds with the aim of preventing, delaying, arresting, or reversing carcinogenesis. Research carried out in the last two decades indicates that natural polyphenols isolated from plants (as well as their derivatives and synthetic analogs) exhibit pleiotropic actions toward cancer cells and therefore they could be used in both cancer prevention and therapy. This review discusses selected covalent modifications of polyphenols as a means for increasing their anticancer potential in relation to the parent compounds. The modifications include hydroxylation, methylation, acylation, and galloylation, among others. They were demonstrated to enhance cytotoxic, pro-oxidant, antiproliferative, proapoptotic, proautophagic, and antimigratory activities of phenolics toward various cancer cell lines in vitro. Importantly, some derivatives proved to suppress tumor growth and metastasis in animal models more strongly than the parent compounds. Some of the above-mentioned covalent modifications were also shown to increase absorption and tissue distribution of tested phenolic compounds in vivo. Anticancer clinical trials with polyphenol derivatives therefore seem warranted.
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Affiliation(s)
| | - Jakub Fichna
- Department of Biochemistry, Medical University of Lodz, Lodz, Poland
| | - Sylwia Gorlach
- Department of Biochemistry, Medical University of Lodz, Lodz, Poland
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Asakawa T, Yoshida A, Hirooka Y, Suzuki T, Itoh K, Shimizu K, Oku N, Furuta T, Wakimoto T, Inai M, Kan T. Synthesis of Chemical-Biology Tools Enabling in vivo Imaging and Analysis of Epigallocatechin Gallate. HETEROCYCLES 2016. [DOI: 10.3987/com-15-s(t)25] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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13
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Inai M, Asakawa T, Kan T. Synthesis of Food Effective Constituents toward the Development for Chemical Biology Investigations. J SYN ORG CHEM JPN 2016. [DOI: 10.5059/yukigoseikyokaishi.74.412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | | | - Toshiyuki Kan
- School of Pharmaceutical Sciences, University of Shizuoka
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Tofolean IT, Ganea C, Ionescu D, Filippi A, Garaiman A, Goicea A, Gaman MA, Dimancea A, Baran I. Cellular determinants involving mitochondrial dysfunction, oxidative stress and apoptosis correlate with the synergic cytotoxicity of epigallocatechin-3-gallate and menadione in human leukemia Jurkat T cells. Pharmacol Res 2015; 103:300-17. [PMID: 26687095 DOI: 10.1016/j.phrs.2015.12.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 12/09/2015] [Accepted: 12/09/2015] [Indexed: 12/17/2022]
Abstract
We have investigated the growth-suppressive action of epigallocatechin-3-gallate (EGCG) on human leukemia Jurkat T cells. Results show a strong correlation between the dose-dependent reduction of clonogenic survival following acute EGCG treatments and the EGCG-induced decline of the mitochondrial level of Ca(2+). The cell killing ability of EGCG was synergistically enhanced by menadione. In addition, the cytotoxic effect of EGCG applied alone or in combination with menadione was accompanied by apoptosis induction. We also observed that in acute treatments EGCG displays strong antioxidant properties in the intracellular milieu, but concurrently triggers some oxidative stress generating mechanisms that can fully develop on a longer timescale. In parallel, EGCG dose-dependently induced mitochondrial depolarization during exposure, but this condition was subsequently reversed to a persistent hyperpolarized mitochondrial state that was dependent on the activity of respiratory Complex I. Fluorimetric measurements suggest that EGCG is a mitochondrial Complex III inhibitor and indicate that EGCG evokes a specific cellular fluorescence with emission at 400nm and two main excitation bands (at 330nm and 350nm) that may originate from a mitochondrial supercomplex containing dimeric Complex III and dimeric ATP-synthase, and therefore could provide a valuable means to characterize the functional properties of the respiratory chain.
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Affiliation(s)
- Ioana Teodora Tofolean
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Constanta Ganea
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Diana Ionescu
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Alexandru Filippi
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Alexandru Garaiman
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Alexandru Goicea
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Mihnea-Alexandru Gaman
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Alexandru Dimancea
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania
| | - Irina Baran
- "Carol Davila" University of Medicine and Pharmacy, Dept. of Biophysics, 8 Eroii Sanitari, 050474 Bucharest, Romania.
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15
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López-Gutiérrez N, Romero-González R, Plaza-Bolaños P, Martínez Vidal JL, Garrido Frenich A. Identification and quantification of phytochemicals in nutraceutical products from green tea by UHPLC-Orbitrap-MS. Food Chem 2014; 173:607-18. [PMID: 25466066 DOI: 10.1016/j.foodchem.2014.10.092] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2013] [Revised: 06/16/2014] [Accepted: 10/17/2014] [Indexed: 01/27/2023]
Abstract
A method has been developed and validated for the simultaneous detection and quantification of phytochemicals in nutraceutical products obtained from green tea. For that purpose, ultra-high performance liquid chromatography coupled to single-stage Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap-MS) has been used. A database containing 37 compounds has been used for the detection and identification of the target compounds. The developed methodology was based on solid-liquid extraction, using a mixture of methanol:H2O (80:20, v/v, pH 4), followed by dilution (10 times) with a mixture of ammonium acetate:methanol (50:50, v/v). Chromatographic conditions were optimised and full scan accurate mass data acquisition using electrospray ionisation in positive and negative ion mode was used. Moreover, all-ion fragmentation mode was used to get information of fragment ions, and they were used for identification purposes. The developed method was validated, obtaining repeatability (intra-day) and inter-day precision values (expressed as relative standard deviation, RSD) lower than 16% and 20%, respectively. Lower limits were also evaluated and limits of detection (LODs) ranged from 1 to 50 μg L(-1), while limits of quantification (LOQs) ranged from 2 to 150 μg L(-1). Recovery was performed at five levels and it ranged from 70% to 109%. Finally, this method was used to evaluate the phytochemical content in 10 samples (tablets or capsules), showing concentrations of (+)-catechin, (-)-epicatechin, gallic acid, (-)-gallocatechin and quercetin-3-O-rutinoside, ranging from 258 (C6) to 10,729 (C6) mg kg(-1).
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Affiliation(s)
- Noelia López-Gutiérrez
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain
| | - Roberto Romero-González
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain
| | - Patricia Plaza-Bolaños
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain
| | - José Luis Martínez Vidal
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain
| | - Antonia Garrido Frenich
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain.
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16
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Kan T, Hiza A, Tsukaguchi Y, Ogawa T, Inai M, Asakawa T, Hamashima Y. Synthetic Studies of Fisetin, Myricetin and Nobiletin Analogs and Related Probe Molecules. HETEROCYCLES 2014. [DOI: 10.3987/com-13-s(s)107] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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17
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Rizzi F, Naponelli V, Silva A, Modernelli A, Ramazzina I, Bonacini M, Tardito S, Gatti R, Uggeri J, Bettuzzi S. Polyphenon E(R), a standardized green tea extract, induces endoplasmic reticulum stress, leading to death of immortalized PNT1a cells by anoikis and tumorigenic PC3 by necroptosis. Carcinogenesis 2013; 35:828-39. [PMID: 24343359 DOI: 10.1093/carcin/bgt481] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Increasing doses of Polyphenon E®, a standardized green tea extract, were given to PNT1a and PC3 prostate epithelial cells mimicking initial and advanced stages of prostate cancer (PCa), respectively. Cell death occurred in both cell lines, with PNT1a being more sensitive [half-maximal inhibitory concentration (IC50) = 35 μg/ml] than PC3 (IC50 = 145 μg/ml) to Polyphenon E®. Cell cycle arrest occurred at G0/G1 checkpoint for PNT1a, and G2/M for PC3 cells. Endoplasmic reticulum stress (ERS) and unfolded protein response (UPR) occurred in both cell lines, with each exhibiting different timing in response to Polyphenon E®. Autophagy was transiently activated in PNT1a cells within 12 h after treatment as a survival response to overcome ERS; then activation of caspases and cleavage of poly (ADP ribose) polymerase 1 occurred, committing cells to anoikis death. Polyphenon E® induced severe ERS in PC3 cells, causing a dramatic enlargement of the ER; persistent activation of UPR produced strong upregulation of GADD153/CHOP, a key protein of ERS-mediated cell death. Thereafter, GADD153/CHOP activated Puma, a BH3-only protein, committing cells to necroptosis, a programmed caspase-independent mechanism of cell death. Our results provide a foundation for the identification of novel targets and strategies aimed at sensitizing apoptosis-resistant cells to alternative death pathways.
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Affiliation(s)
- Federica Rizzi
- Department of Biomedicine, Biotechnology and Translational Research and
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18
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Li KK, Liu CL, Tam JCW, Kwok HF, Lau CP, Leung PC, Ko CH, Ye CX. In vitro and in vivo mechanistic study of a novel proanthocyanidin, GC-(4→8)-GCG from cocoa tea (Camellia ptilophylla) in antiangiogenesis. J Nutr Biochem 2013; 25:319-28. [PMID: 24524904 DOI: 10.1016/j.jnutbio.2013.11.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 10/29/2013] [Accepted: 11/09/2013] [Indexed: 12/29/2022]
Abstract
Angiogenesis, the process of blood vessel formation, is critical to tumor growth. Ant-angiogenic strategies demonstrated importance in cancer therapy. Cocoa tea (Camellia ptilophylla), a naturally decaffeinated tea commonly consumed as a healthy drink in southern China, had recently been found to be a potential candidate for antiangiogenesis. A novel proanthocyanidin, GC-(4→8)-GCG, which consisted of gallocatechin and gallocatechin 3-O gallate moieties, was discovered and thought to be one of the effective candidates for antiangiogenesis. Hence, the present study aimed to evaluate the antiangiogenesis activities of GC-(4→8)-GCG in vitro and in vivo, and SU5416 was applied as a positive control. The inhibitory effects of GC-(4→8)-GCG on three important processes involved in angiogenesis, i.e., proliferation, migration and differentiation, were examined using human microvascular endothelial cell line HMEC-1 by MTT assay, scratch assay and tube formation assay, respectively. Using transgenic zebrafish embryos TG(fli1:EGFP)y1/+(AB) as an animal model of angiogenesis, the antiangiogenic effect of GC-(4→8)-GCG was further verified in vivo. Our results demonstrated that GC-(4→8)-GCG significantly inhibited migration (P<.001) and tubule formation (P<.001-.05) of HMEC-1 in dose-dependent manner. Regarding intracellular signal transduction, GC-(4→8)-GCG attenuated the phosphorylation of ERK, Akt and p38 dose-dependently in HMEC-1. In zebrafish embryo, the formation of new blood vessels was effectively inhibited by GC-(4→8)-GCG in a dose-dependent manner after 3 days of treatment (P<.001-.05). In conclusion, these results revealed that our novel proanthocyanidin, GC-(4→8)-GCG might be a potential and promising agent of natural resource to be further developed as an antiangiogenic agent.
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Affiliation(s)
- Kai-kai Li
- Department of Biology, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Cheuk-lun Liu
- Institute of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, Hong Kong, China
| | - Jacqueline Chor-wing Tam
- Institute of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, Hong Kong, China
| | - Hin-fai Kwok
- Institute of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, Hong Kong, China
| | - Ching-po Lau
- Institute of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, Hong Kong, China
| | - Ping-chung Leung
- Institute of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute
| | - Chun-hay Ko
- Institute of Chinese Medicine, The Chinese University of Hong Kong, Hong Kong, China; State Key Laboratory of Phytochemistry and Plant Resources in West China, The Chinese University of Hong Kong, Hong Kong, China; The Chinese University of Hong Kong Shenzhen Research Institute.
| | - Chuang-xing Ye
- Department of Biology, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
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19
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Valenti D, de Bari L, Manente GA, Rossi L, Mutti L, Moro L, Vacca RA. Negative modulation of mitochondrial oxidative phosphorylation by epigallocatechin-3 gallate leads to growth arrest and apoptosis in human malignant pleural mesothelioma cells. Biochim Biophys Acta Mol Basis Dis 2013; 1832:2085-96. [PMID: 23911347 DOI: 10.1016/j.bbadis.2013.07.014] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Revised: 07/11/2013] [Accepted: 07/23/2013] [Indexed: 12/29/2022]
Abstract
Increasing evidence reveals a large dependency of epithelial cancer cells on oxidative phosphorylation (OXPHOS) for energy production. In this study we tested the potential of epigallocatechin-3-gallate (EGCG), a natural polyphenol known to target mitochondria, in inducing OXPHOS impairment and cell energy deficit in human epitheliod (REN cells) and biphasic (MSTO-211H cells) malignant pleural mesothelioma (MMe), a rare but highly aggressive tumor with high unmet need for treatment. Due to EGCG instability that causes H2O2 formation in culture medium, the drug was added to MMe cells in the presence of exogenous superoxide dismutase and catalase, already proved to stabilize the EGCG molecule and prevent EGCG-dependent reactive oxygen species formation. We show that under these experimental conditions, EGCG causes the selective arrest of MMe cell growth with respect to normal mesothelial cells and the induction of mitochondria-mediated apoptosis, as revealed by early mitochondrial ultrastructure modification, swelling and cytochrome c release. We disclose a novel mechanism by which EGCG induces apoptosis through the impairment of mitochondrial respiratory chain complexes, particularly of complex I, II and ATP synthase. This induces a strong reduction in ATP production by OXPHOS, that is not adequately counterbalanced by glycolytic shift, resulting in cell energy deficit, cell cycle arrest and apoptosis. The EGCG-dependent negative modulation of mitochondrial energy metabolism, selective for cancer cells, gives an important input for the development of novel pharmacological strategies for MMe.
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Affiliation(s)
- Daniela Valenti
- Institute of Biomembranes and Bioenergetics, National Council of Research, Bari, Italy.
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20
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Bansal S, Vyas S, Bhattacharya S, Sharma M. Catechin prodrugs and analogs: a new array of chemical entities with improved pharmacological and pharmacokinetic properties. Nat Prod Rep 2013; 30:1438-54. [DOI: 10.1039/c3np70038k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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21
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Detailed analysis of apoptosis and delayed luminescence of human leukemia Jurkat T cells after proton irradiation and treatments with oxidant agents and flavonoids. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2012; 2012:498914. [PMID: 22829956 PMCID: PMC3397210 DOI: 10.1155/2012/498914] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Accepted: 05/14/2012] [Indexed: 11/24/2022]
Abstract
Following previous work, we investigated in more detail the relationship between apoptosis and delayed luminescence (DL) in human leukemia Jurkat T cells under a wide variety of treatments. We used menadione and hydrogen peroxide to induce oxidative stress and two flavonoids, quercetin, and epigallocatechin gallate, applied alone or in combination with menadione or H2O2. 62 MeV proton beams were used to irradiate cells under a uniform dose of 2 or 10 Gy, respectively. We assessed apoptosis, cell cycle distributions, and DL. Menadione, H2O2 and quercetin were potent inducers of apoptosis and DL inhibitors. Quercetin decreased clonogenic survival and the NAD(P)H level in a dose-dependent manner. Proton irradiation with 2 Gy but not 10 Gy increased the apoptotic rate. However, both doses induced a substantial G2/M arrest. Quercetin reduced apoptosis and prolonged the G2/M arrest induced by radiation. DL spectroscopy indicated that proton irradiation disrupted the electron flow within Complex I of the mitochondrial respiratory chain, thus explaining the massive necrosis induced by 10 Gy of protons and also suggested an equivalent action of menadione and quercetin at the level of the Fe/S center N2, which may be mediated by their binding to a common site within Complex I, probably the rotenone-binding site.
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22
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PI3K/AKT/PTEN Signaling as a Molecular Target in Leukemia Angiogenesis. Adv Hematol 2012; 2012:843085. [PMID: 22505939 PMCID: PMC3299269 DOI: 10.1155/2012/843085] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 12/11/2011] [Indexed: 11/17/2022] Open
Abstract
PI3K/AKT/PTEN pathway is important in the regulation of angiogenesis mediated by vascular endothelial growth factor in many tumors including leukemia. The signaling pathway is activated in leukemia patients as well as leukemia cell lines together with a decrease in the expression of PTEN gene. The mechanism by which the signaling pathway regulates angiogenesis remains to be further elucidated. However, it has become an attractive target for drug therapy against leukemia, because angiogenesis is a key process in malignant cell growth. In this paper, we will focus on the roles and mechanisms of PI3K/AKT/PTEN pathway in regulating angiogenesis.
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23
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Konta L, Száraz P, Magyar JÉ, Révész K, Bánhegyi G, Mandl J, Csala M. Inhibition of glycoprotein synthesis in the endoplasmic reticulum as a novel anticancer mechanism of (-)-epigallocatechin-3-gallate. Biofactors 2011; 37:468-76. [PMID: 22162335 DOI: 10.1002/biof.189] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2011] [Accepted: 09/20/2011] [Indexed: 11/05/2022]
Abstract
(-)-Epigallocatechin-3-gallate (EGCG) has been found to trigger the unfolded protein response (UPR) likely due to the inhibition of glucosidase II, a key enzyme of glycoprotein processing and quality control in the endoplasmic reticulum (ER). These findings strongly suggest that EGCG interferes with glycoprotein maturation and sorting in the ER. This hypothesis was tested in SK-Mel28 human melanoma cells by assessing the effect of EGCG and deoxynojirimycin (DNJ) on the synthesis of two endogenous glycoproteins. Both tyrosinase and vascular endothelial growth factor (VEGF) protein levels were remarkably reduced despite unaltered mRNA expression in EGCG- or DNJ-treated cells compared to control. The hindrance of tyrosinase and VEGF protein synthesis could be prevented by proteasome inhibitor, lactacystine. Collectively, our results support that glucosidase II inhibitor EGCG interferes with protein processing and quality control in the ER, which diverts tyrosinase, VEGF, and likely other glycoproteins towards proteasomal degradation. This mechanism provides a novel therapeutic approach in dermatology and might play an important role in the antitumor effect or hepatotoxicity of EGCG.
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Affiliation(s)
- Laura Konta
- Department of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University & MTA-SE Pathobiochemistry Research Group, Budapest, Hungary
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24
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Révész K, Tüttő A, Szelényi P, Konta L. Tea flavan-3-ols as modulating factors in endoplasmic reticulum function. Nutr Res 2011; 31:731-40. [DOI: 10.1016/j.nutres.2011.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2011] [Revised: 09/07/2011] [Accepted: 09/15/2011] [Indexed: 01/04/2023]
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