1
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Romanucci V, Pagano R, Kandhari K, Zarrelli A, Petrone M, Agarwal C, Agarwal R, Di Fabio G. 7- O-tyrosyl Silybin Derivatives as a Novel Set of Anti-Prostate Cancer Compounds. Antioxidants (Basel) 2024; 13:418. [PMID: 38671866 PMCID: PMC11047488 DOI: 10.3390/antiox13040418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 03/24/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Silybin is a natural compound extensively studied for its hepatoprotective, neuroprotective and anticancer properties. Envisioning the enhancement of silybin potential by suitable modifications in its chemical structure, here, a series of new 7-O-alkyl silybins derivatives were synthesized by the Mitsunobu reaction starting from the silybins and tyrosol-based phenols, such as tyrosol (TYR, 3), 3-methoxytyrosol (MTYR, 4), and 3-hydroxytyrosol (HTYR, 5). This research sought to explore the antioxidant and anticancer properties of eighteen new derivatives and their mechanisms. In particular, the antioxidant properties of new derivatives outlined by the DPPH assay showed a very pronounced activity depending on the tyrosyl moiety (HTYR > MTYR >> TYR). A significant contribution of the HTYR moiety was observed for silybins and 2,3-dehydro-silybin-based derivatives. According to the very potent antioxidant activity, 2,3-dehydro-silybin derivatives 15ab, 15a, and 15b exerted the most potent anticancer activity in human prostate cancer PC-3 cells. Furthermore, flow cytometric analysis for cell cycle and apoptosis revealed that 15ab, 15a, and 15b induce strong G1 phase arrest and increase late apoptotic population in PC-3 cells. Additionally, Western blotting for apoptotic marker cleaved caspase-3 confirmed apoptosis induction by these silybin derivatives in PC-3 cells. These findings hold significant importance in the investigation of anticancer properties of silybin derivatives and strongly encourage swift investigation in pre-clinical models and clinical trials.
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Affiliation(s)
- Valeria Romanucci
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Monte Sant’Angelo, Via Cintia 4, I-80126 Napoli, Italy; (V.R.); (R.P.); (A.Z.); (M.P.)
| | - Rita Pagano
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Monte Sant’Angelo, Via Cintia 4, I-80126 Napoli, Italy; (V.R.); (R.P.); (A.Z.); (M.P.)
| | - Kushal Kandhari
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (K.K.); (C.A.); (R.A.)
| | - Armando Zarrelli
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Monte Sant’Angelo, Via Cintia 4, I-80126 Napoli, Italy; (V.R.); (R.P.); (A.Z.); (M.P.)
| | - Maria Petrone
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Monte Sant’Angelo, Via Cintia 4, I-80126 Napoli, Italy; (V.R.); (R.P.); (A.Z.); (M.P.)
| | - Chapla Agarwal
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (K.K.); (C.A.); (R.A.)
| | - Rajesh Agarwal
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; (K.K.); (C.A.); (R.A.)
| | - Giovanni Di Fabio
- Department of Chemical Sciences, University of Naples “Federico II”, Complesso Monte Sant’Angelo, Via Cintia 4, I-80126 Napoli, Italy; (V.R.); (R.P.); (A.Z.); (M.P.)
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2
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Xu C, Yuan Y, Pang P, Yang H, Zhang Q, Yuan D, Qi W. Urinary excretion of silibinin diastereoisomers and their conjugated metabolites in rat and human at different dosages. Biomed Chromatogr 2022; 36:e5480. [PMID: 35962523 DOI: 10.1002/bmc.5480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 07/31/2022] [Accepted: 08/10/2022] [Indexed: 11/11/2022]
Abstract
Silibinin is a mixture of two flavonoid lignan silibinins A and B from the seeds of milk thistle (Silybum marianum L.). Using UPLC/Q-TOFMS, a total of 18 metabolites were identified in rat and human urine samples after oral administration of Silibinin Capsule. Furthermore, nine glucuronides and/or sulfated metabolites and two prototype compounds were simultaneously quantified in rat urine after oral administration of Silibinin Capsule at 50 and 100 mg/kg. Over a 72-h period, 27.6% and 23.3% of the silibinin were excreted in the forms of eleven metabolites in urine, among which, 5 major metabolites, including silibinin A-7-O-β-glucuronide (SA-7G), silibinin B-7-O-β-glucuronide (SB-7G), silibinin A-5-O-β-glucuronide (SA-5G), silibinin B-5-O-β-glucuronide (SB-5G) and silibinin A-20-O-glucuronide (SA-20G), accounted for 20.5% and 15.5% of the dosages separatively at doses of 50 and 100 mg/kg. These results suggested that glucuronidation at the C7-, C5- and C20- hydroxyls was the primary metabolic pathway of silibinin diastereoisomers in vivo. The present results provide helpful information for in vivo metabolism and clinical usage of Silibinin Capsule.
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Affiliation(s)
- Cong Xu
- Department of Traditional Chinese Medicine, Shenyang Pharmaceutical University, Shenyang, China
| | - Yuan Yuan
- Outpatient Department of Emergency Science, Sichuan Armed Police Corps Hospital, Leshan, China
| | - Ping Pang
- Department of Traditional Chinese Medicine, Shenyang Pharmaceutical University, Shenyang, China
| | - Huanhuan Yang
- Department of Traditional Chinese Medicine, Shenyang Pharmaceutical University, Shenyang, China
| | - Qiang Zhang
- Department of Traditional Chinese Medicine, Shenyang Pharmaceutical University, Shenyang, China
| | - Dan Yuan
- Department of Traditional Chinese Medicine, Shenyang Pharmaceutical University, Shenyang, China
| | - Wen Qi
- Department of Traditional Chinese Medicine, Shenyang Pharmaceutical University, Shenyang, China
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3
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Persico M, García-Viñuales S, Santoro AM, Lanza V, Tundo GR, Sbardella D, Coletta M, Romanucci V, Zarrelli A, Di Fabio G, Fattorusso C, Milardi D. Silybins are stereospecific regulators of the 20S proteasome. Bioorg Med Chem 2022; 66:116813. [PMID: 35576657 DOI: 10.1016/j.bmc.2022.116813] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 05/05/2022] [Accepted: 05/05/2022] [Indexed: 11/15/2022]
Abstract
A reduced proteasome activity tiles excessive amyloid growth during the progress of protein conformational diseases (PCDs). Hence, the development of safe and effective proteasome enhancers represents an attractive target for the therapeutic treatment of these chronic disorders. Here we analyze two natural diastereoisomers belonging to the family of flavonolignans, Sil A and Sil B, by evaluating their capacity to increase proteasome activity. Enzyme assays carried out on yeast 20S (y20S) proteasome and in parallel on a permanently "open gate" mutant (α3ΔN) evidenced that Sil B is a more efficient 20S activator than Sil A. Conversely, in the case of human 20S proteasome (h20S) a higher affinity and more efficient activation is observed for Sil A. Driven by experimental data, computational studies further demonstrated that the taxifolin group of both diastereoisomers plays a crucial role in their anchoring to the α5/α6 groove of the outer α-ring. However, due to the different stereochemistry at C-7" and C-8" of ring D, only Sil A was able to reproduce the interactions responsible for h20S proteasome activation induced by their cognate regulatory particles. The provided silybins/h20S interaction models allowed us to rationalize their different ability to activate the peptidase activities of h20S and y20S. Our results provide structural details concerning the important role played by stereospecific interactions in driving Sil A and Sil B binding to the 20S proteasome and may support future rational design of proteasome enhancers.
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Affiliation(s)
- Marco Persico
- Department of Pharmacy, Università di Napoli "Federico II", Via D. Montesano 49, 80131 Napoli, Italy
| | - Sara García-Viñuales
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Anna Maria Santoro
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Valeria Lanza
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | | | | | | | - Valeria Romanucci
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Armando Zarrelli
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Giovanni Di Fabio
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Caterina Fattorusso
- Department of Pharmacy, Università di Napoli "Federico II", Via D. Montesano 49, 80131 Napoli, Italy.
| | - Danilo Milardi
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy.
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4
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Romanucci V, Giordano M, Pagano R, Zimbone S, Giuffrida ML, Milardi D, Zarrelli A, Di Fabio G. Investigation on the solid-phase synthesis of silybin prodrugs and their timed-release. Bioorg Med Chem 2021; 50:116478. [PMID: 34695708 DOI: 10.1016/j.bmc.2021.116478] [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: 09/03/2021] [Revised: 10/07/2021] [Accepted: 10/11/2021] [Indexed: 12/15/2022]
Abstract
Prodrugs are ingenious derivatives of therapeutic agents designed to improve the pharmacokinetic profile of the drug. Here, we report an efficient and regioselective solid phase approach for obtaining new prodrugs of 9″-silybins conjugated with 3'-ribonucleotide units (uridine and adenosine) as pro-moieties. Uridine and adenosine conjugates were obtained in good yields (41-50%), beginning with silibinin and its diastereomers (silybin A and silybin B), using a NovaSyn® support functionalized with an ad hoc linker, which allowed selective detachment of only the desired products. As expected, the solubility of both uridine and adenosine conjugates was higher than that of the parental natural product (5 mg/mL and 3 mg/mL for uridine and adenosine, respectively). Our investigations revealed that uridine conjugates were quickly cleaved by RNase A, releasing silybin drugs, even at low enzyme concentrations. No toxic effects were found for any ribonucleotide conjugate on differentiated neuroblastoma SH-SY5Y cells when tested at increasing concentrations. All results strongly encourage further investigations of uridine-silybin prodrugs as potential therapeutic agents for both oral and intravenous administration. The present synthetic approach represents a valuable strategy to the future design of new prodrugs with modified nucleoside pro-moieties to modulate the pharmacokinetics of silybins or different natural products with strong pharmacological activities but poor bioavailability.
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Affiliation(s)
- Valeria Romanucci
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Maddalena Giordano
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Rita Pagano
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Stefania Zimbone
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Maria Laura Giuffrida
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Danilo Milardi
- Istituto di Cristallografia, Consiglio Nazionale delle Ricerche, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Armando Zarrelli
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Giovanni Di Fabio
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy.
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5
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Fallah M, Davoodvandi A, Nikmanzar S, Aghili S, Mirazimi SMA, Aschner M, Rashidian A, Hamblin MR, Chamanara M, Naghsh N, Mirzaei H. Silymarin (milk thistle extract) as a therapeutic agent in gastrointestinal cancer. Biomed Pharmacother 2021; 142:112024. [PMID: 34399200 PMCID: PMC8458260 DOI: 10.1016/j.biopha.2021.112024] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Revised: 08/01/2021] [Accepted: 08/07/2021] [Indexed: 02/07/2023] Open
Abstract
Silymarin contains a group of closely-related flavonolignan compounds including silibinin, and is extracted from Silybum marianum species, also called milk thistle. Silymarin has been shown to protect the liver in both experimental models and clinical studies. The chemopreventive activity of silymarin has shown some efficacy against cancer both in vitro and in vivo. Silymarin can modulate apoptosis in vitro and survival in vivo, by interfering with the expression of cell cycle regulators and apoptosis-associated proteins. In addition to its anti-metastatic activity, silymarin has also been reported to exhibit anti-inflammatory activity. The chemoprotective effects of silymarin and silibinin (its major constituent) suggest they could be applied to reduce the side effects and increase the anti-cancer effects of chemotherapy and radiotherapy in various cancer types, especially in gastrointestinal cancers. This review examines the recent studies and summarizes the mechanistic pathways and down-stream targets of silymarin in the therapy of gastrointestinal cancer.
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Affiliation(s)
- Maryam Fallah
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran; Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Amirhossein Davoodvandi
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran; Cancer Immunology Project (CIP), Universal Scientific Education and Research Network (USERN), Tehran, Iran
| | - Shahin Nikmanzar
- Department of Neurosurgery, School of Medicine, Baqiyatallah University of Medical Sciences, Tehran, Iran
| | - Sarehnaz Aghili
- Department of Gynecology and Obstetrics, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Seyed Mohammad Ali Mirazimi
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran; School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10463, USA
| | - Amir Rashidian
- Department of Pharmacology, School of Medicine, Aja University of Medical Sciences, Tehran, Iran
| | - Michael R Hamblin
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein 2028, South Africa
| | - Mohsen Chamanara
- Department of Pharmacology, School of Medicine, Aja University of Medical Sciences, Tehran, Iran; Toxicology Research Center, Aja University of Medical Sciences, Tehran, Iran.
| | - Navid Naghsh
- Faculty of Pharmacy, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
| | - Hamed Mirzaei
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran.
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6
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Křen V. Chirality Matters: Biological Activity of Optically Pure Silybin and Its Congeners. Int J Mol Sci 2021; 22:ijms22157885. [PMID: 34360650 PMCID: PMC8346157 DOI: 10.3390/ijms22157885] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 07/19/2021] [Indexed: 12/31/2022] Open
Abstract
This review focuses on the specific biological effects of optically pure silymarin flavo-nolignans, mainly silybins A and B, isosilybins A and B, silychristins A and B, and their 2,3-dehydro derivatives. The chirality of these flavonolignans is also discussed in terms of their analysis, preparative separation and chemical reactions. We demonstrated the specific activities of the respective diastereomers of flavonolignans and also the enantiomers of their 2,3-dehydro derivatives in the 3D anisotropic systems typically represented by biological systems. In vivo, silymarin flavonolignans do not act as redox antioxidants, but they play a role as specific ligands of biological targets, according to the "lock-and-key" concept. Estrogenic, antidiabetic, anticancer, antiviral, and antiparasitic effects have been demonstrated in optically pure flavonolignans. Potential application of pure flavonolignans has also been shown in cardiovascular and neurological diseases. Inhibition of drug-metabolizing enzymes and modulation of multidrug resistance activity by these compounds are discussed in detail. The future of "silymarin applications" lies in the use of optically pure components that can be applied directly or used as valuable lead structures, and in the exploration of their true molecular effects.
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Affiliation(s)
- Vladimír Křen
- Laboratory of Biotransformation, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic
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7
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Tvrdý V, Pourová J, Jirkovský E, Křen V, Valentová K, Mladěnka P. Systematic review of pharmacokinetics and potential pharmacokinetic interactions of flavonolignans from silymarin. Med Res Rev 2021; 41:2195-2246. [PMID: 33587317 DOI: 10.1002/med.21791] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 01/06/2021] [Accepted: 01/29/2021] [Indexed: 12/15/2022]
Abstract
Silymarin is an extract from the seeds (fruits) of Silybum marianum that contains flavonolignans and flavonoids. Although it is frequently used as a hepatoprotective agent, its application remains somewhat debatable, in particular, due to the low oral bioavailability of flavonolignans. Moreover, there are claims of its potential interactions with concomitantly used drugs. This review aims at a systematic summary and critical assessment of known information on the pharmacokinetics of particular silymarin flavonolignans. There are two known major reasons for poor systemic oral bioavailability of flavonolignans: (1) rapid conjugation in intestinal cells or the liver and (2) efflux of parent flavonolignans or formed conjugates back to the lumen of the gastrointestinal tract by intestinal cells and rapid excretion by the liver into the bile. The metabolism of phase I appears to play a minor role, in contrast to extensive conjugation and indeed the unconjugated flavonolignans reach low plasma levels after common doses. Only about 1%-5% of the administered dose is eliminated by the kidneys. Many in vitro studies tested the inhibitory potential of silymarin and its components toward different enzymes and transporters involved in the absorption, metabolism, and excretion of xenobiotics. In most cases, effective concentrations are too high to be relevant under real biological conditions. Most human studies showed no silymarin-drug interactions explainable by these suggested interferences. More interactions were found in animal studies, likely due to the much higher doses administered.
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Affiliation(s)
- Václav Tvrdý
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Hradec Králové, Czech Republic
| | - Jana Pourová
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Hradec Králové, Czech Republic
| | - Eduard Jirkovský
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Hradec Králové, Czech Republic
| | - Vladimír Křen
- Laboratory of Biotransformation, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Kateřina Valentová
- Laboratory of Biotransformation, Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
| | - Přemysl Mladěnka
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Hradec Králové, Czech Republic
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8
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Chen X, Deng X, Han X, Liang Y, Meng Z, Liu R, Su W, Zhu H, Fu T. Inhibition of Lysozyme Amyloid Fibrillation by Silybin Diastereoisomers: The Effects of Stereochemistry. ACS OMEGA 2021; 6:3307-3318. [PMID: 33553948 PMCID: PMC7860231 DOI: 10.1021/acsomega.0c05788] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 01/08/2021] [Indexed: 05/24/2023]
Abstract
Silybin is a flavonoid lignin compound consisting of two diastereomers with nearly equal molar ratios. It has been reported that silybin can effectively inhibit the aggregation of amyloid protein, but the difference between the two silybin diastereomers has been rarely studied. In this work, the inhibitory ability of silybin to hen egg-white lysozyme (HEWL) was demonstrated, and the difference of kinetic parameters of two diastereomers was analyzed. Fluorescence quenching titration was utilized to analyze the binding differences to native HEWL between the diastereomers, and transmission electron microscopy (TEM) was utilized to analyze the characteristics of the surface of various samples. The differences between hydrophobicity and the secondary structure among several HEWL samples were measured by the 8-anilino-1-naphthalene sulfonic (ANS) acid fluorescence probe, Raman spectra, and far-UV circular dichroism. Moreover, the differences in the binding energy of these two diastereomers with HEWL were analyzed by molecular docking. Also, we have investigated the effect of silybin diastereomers on HEWL fibril-induced cytotoxicity in SH-SY5Y cells. Results show that silybin has a certain inhibitory effect on the HEWL fibrillogenesis process, while silybin B (SB) has a more significant inhibitory effect than silybin A (SA), especially at high concentrations. This work provides some insights into the screening of amyloid inhibitors from complicated natural products and indicates that SB has the prospect of further development as an amyloid inhibitor.
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Affiliation(s)
- Xuanyu Chen
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Xiaomin Deng
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Xingxing Han
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Yinmei Liang
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Zhiping Meng
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Rui Liu
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
| | - Wenqiang Su
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
| | - Huaxu Zhu
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
- Separation
Engineering of Chinese Traditional Medicine Compound, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Tingming Fu
- School
of Pharmacy, Nanjing University of Chinese
Medicine, Nanjing 210023, China
- Plant
Medicine Research and Technological Development Center of Jiangsu
Province, Nanjing 210023, China
- Separation
Engineering of Chinese Traditional Medicine Compound, Nanjing University of Chinese Medicine, Nanjing 210023, China
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9
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Tuli HS, Mittal S, Aggarwal D, Parashar G, Parashar NC, Upadhyay SK, Barwal TS, Jain A, Kaur G, Savla R, Sak K, Kumar M, Varol M, Iqubal A, Sharma AK. Path of Silibinin from diet to medicine: A dietary polyphenolic flavonoid having potential anti-cancer therapeutic significance. Semin Cancer Biol 2020; 73:196-218. [PMID: 33130037 DOI: 10.1016/j.semcancer.2020.09.014] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 09/11/2020] [Accepted: 09/29/2020] [Indexed: 02/07/2023]
Abstract
In the last few decades, targeting cancer by the use of dietary phytochemicals has gained enormous attention. The plausible reason and believe or mind set behind this fact is attributed to either lesser or no side effects of natural compounds as compared to the modern chemotherapeutics, or due to their conventional use as dietary components by mankind for thousands of years. Silibinin is a naturally derived polyphenol (a flavonolignans), possess following biochemical features; molecular formula C25H22O10, Molar mass: 482.44 g/mol, Boiling point 793 °C, with strikingly high antioxidant and anti-tumorigenic properties. The anti-cancer properties of Silibinin are determined by a variety of cellular pathways which include induction of apoptosis, cell cycle arrest, inhibition of angiogenesis and metastasis. In addition, Silibinin controls modulation of the expression of aberrant miRNAs, inflammatory response, and synergism with existing anti-cancer drugs. Therefore, modulation of a vast array of cellular responses and homeostatic aspects makes Silibinin an attractive chemotherapeutic agent. However, like other polyphenols, the major hurdle to declare Silibinin a translational chemotherapeutic agent, is its lesser bioavailability. After summarizing the chemistry and metabolic aspects of Silibinin, this extensive review focuses on functional aspects governed by Silibinin in chemoprevention with an ultimate goal of summarizing the evidence supporting the chemopreventive potential of Silibinin and clinical trials that are currently ongoing, at a single platform.
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Affiliation(s)
- Hardeep Singh Tuli
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, 133 207, Haryana, India
| | - Sonam Mittal
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, India
| | - Diwakar Aggarwal
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, 133 207, Haryana, India
| | - Gaurav Parashar
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, 133 207, Haryana, India
| | | | - Sushil Kumar Upadhyay
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, 133 207, Haryana, India
| | - Tushar Singh Barwal
- Department of Zoology, Central University of Punjab, Bathinda, 151 001, Punjab, India
| | - Aklank Jain
- Department of Zoology, Central University of Punjab, Bathinda, 151 001, Punjab, India
| | - Ginpreet Kaur
- Department of Pharmacology, Shobhaben Pratapbhai Patel School of Pharmacy and Technology Management, SVKM's, NMIMS, Mumbai, 400 056, Maharastra, India
| | - Raj Savla
- Department of Pharmacology, Shobhaben Pratapbhai Patel School of Pharmacy and Technology Management, SVKM's, NMIMS, Mumbai, 400 056, Maharastra, India
| | | | - Manoj Kumar
- Department of Chemistry, Maharishi Markandeshwar University, Sadopur, India
| | - Mehmet Varol
- Department of Molecular Biology and Genetics, Faculty of Science, Mugla Sitki Kocman University, Mugla, TR48000, Turkey
| | - Ashif Iqubal
- Department of Pharmacology, School of Pharmaceutical Education and Research (Formerly Faculty of Pharmacy), Jamia Hamdard (Deemed to be University), Delhi, India
| | - Anil Kumar Sharma
- Department of Biotechnology, Maharishi Markandeshwar (Deemed to be University), Mullana-Ambala, 133 207, Haryana, India.
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10
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García-Viñuales S, Ahmed R, Sciacca MFM, Lanza V, Giuffrida ML, Zimbone S, Romanucci V, Zarrelli A, Bongiorno C, Spinella N, Galati C, Di Fabio G, Melacini G, Milardi D. Trehalose Conjugates of Silybin as Prodrugs for Targeting Toxic Aβ Aggregates. ACS Chem Neurosci 2020; 11:2566-2576. [PMID: 32687307 DOI: 10.1021/acschemneuro.0c00232] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Alzheimer's disease (AD) is linked to the abnormal accumulation of amyloid β peptide (Aβ) aggregates in the brain. Silybin B, a natural compound extracted from milk thistle (Silybum marianum), has been shown to significantly inhibit Aβ aggregation in vitro and to exert neuroprotective properties in vivo. However, further explorations of silybin B's clinical potential are currently limited by three main factors: (a) poor solubility, (b) instability in blood serum, and (c) only partial knowledge of silybin's mechanism of action. Here, we address these three limitations. We demonstrate that conjugation of a trehalose moiety to silybin significantly increases both water solubility and stability in blood serum without significantly compromising its antiaggregation properties. Furthermore, using a combination of biophysical techniques with different spatial resolution, that is, TEM, ThT fluorescence, CD, and NMR spectroscopy, we profile the interactions of the trehalose conjugate with both Aβ monomers and oligomers and evidence that silybin may shield the "toxic" surfaces formed by the N-terminal and central hydrophobic regions of Aβ. Finally, comparative analysis with silybin A, a less active diastereoisomer of silybin B, revealed how even subtle differences in chemical structure may entail different effects on amyloid inhibition. The resulting insight on the mechanism of action of silybins as aggregation inhibitors is anticipated to facilitate the future investigation of silybin's therapeutic potential.
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Affiliation(s)
- Sara García-Viñuales
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Rashik Ahmed
- Departments of Chemistry and Chemical Biology & Biochemistry and Biomedical Sciences, McMaster University, Hamilton ON L8S 4M1, Canada
| | - Michele F. M. Sciacca
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Valeria Lanza
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Maria Laura Giuffrida
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Stefania Zimbone
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Valeria Romanucci
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Armando Zarrelli
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Corrado Bongiorno
- Institute for Microelectronics and Microsystems, National Research Council, Stradale Primosole 50, 95121 Catania, Italy
| | | | - Clelia Galati
- STMicroelectronics, Stradale Primosole 50, 95121 Catania, Italy
| | - Giovanni Di Fabio
- Department of Chemical Sciences, University of Naples Federico II, Via Cintia 4, I-80126 Napoli, Italy
| | - Giuseppe Melacini
- Departments of Chemistry and Chemical Biology & Biochemistry and Biomedical Sciences, McMaster University, Hamilton ON L8S 4M1, Canada
| | - Danilo Milardi
- Consiglio Nazionale delle Ricerche, Istituto di Cristallografia, Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
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11
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Xie Y, Zhang D, Zhang J, Yuan J. Metabolism, Transport and Drug-Drug Interactions of Silymarin. Molecules 2019; 24:E3693. [PMID: 31615114 PMCID: PMC6832356 DOI: 10.3390/molecules24203693] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/11/2019] [Accepted: 10/14/2019] [Indexed: 02/07/2023] Open
Abstract
Silymarin, the extract of milk thistle, and its major active flavonolignan silybin, are common products widely used in the phytotherapy of liver diseases. They also have promising effects in protecting the pancreas, kidney, myocardium, and the central nervous system. However, inconsistent results are noted in the different clinical studies due to the low bioavailability of silymarin. Extensive studies were conducted to explore the metabolism and transport of silymarin/silybin as well as the impact of its consumption on the pharmacokinetics of other clinical drugs. Here, we aimed to summarize and highlight the current knowledge of the metabolism and transport of silymarin. It was concluded that the major efflux transporters of silybin are multidrug resistance-associated protein (MRP2) and breast cancer resistance protein (BCRP) based on results from the transporter-overexpressing cell lines and MRP2-deficient (TR-) rats. Nevertheless, compounds that inhibit the efflux transporters MRP2 and BCRP can enhance the absorption and activity of silybin. Although silymarin does inhibit certain drug-metabolizing enzymes and drug transporters, such effects are unlikely to manifest in clinical settings. Overall, silymarin is a safe and well-tolerated phytomedicine.
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Affiliation(s)
- Ying Xie
- School of Pharmacy, Macau University of Science and Technology, Taipa, Macao 999078, China.
| | - Dingqi Zhang
- School of Pharmacy, Macau University of Science and Technology, Taipa, Macao 999078, China.
| | - Jin Zhang
- School of Pharmacy, Macau University of Science and Technology, Taipa, Macao 999078, China.
| | - Jialu Yuan
- School of Pharmacy, Macau University of Science and Technology, Taipa, Macao 999078, China.
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12
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Pourová J, Applová L, Macáková K, Vopršalová M, Migkos T, Bentanachs R, Biedermann D, Petrásková L, Tvrdý V, Hrubša M, Karlíčková J, Křen V, Valentová K, Mladěnka P. The Effect of Silymarin Flavonolignans and Their Sulfated Conjugates on Platelet Aggregation and Blood Vessels Ex Vivo. Nutrients 2019; 11:nu11102286. [PMID: 31554252 PMCID: PMC6836034 DOI: 10.3390/nu11102286] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 09/20/2019] [Accepted: 09/20/2019] [Indexed: 12/11/2022] Open
Abstract
Silymarin is a traditional drug and food supplement employed for numerous liver disorders. The available studies indicate that its activities may be broader, in particular due to claimed benefits in some cardiovascular diseases, but the contributions of individual silymarin components are unclear. Therefore, we tested silymarin flavonolignans as pure diastereomers as well as their sulfated metabolites for potential vasorelaxant and antiplatelet effects in isolated rat aorta and in human blood, respectively. Eleven compounds from a panel of 17 tested exhibited a vasorelaxant effect, with half maximal effective concentrations (EC50) ranging from 20 to 100 µM, and some substances retained certain activity even in the range of hundreds of nM. Stereomers A were generally more potent as vasorelaxants than stereomers B. Interestingly, the most active compound was a metabolite—silychristin-19-O-sulfate. Although initial experiments showed that silybin, 2,3-dehydrosilybin, and 2,3-dehydrosilychristin were able to substantially block platelet aggregation, their effects were rapidly abolished with decreasing concentration, and were negligible at concentrations ≤100 µM. In conclusion, metabolites of silymarin flavonolignans seem to have biologically relevant vasodilatory properties, but the effect of silymarin components on platelets is low or negligible.
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Affiliation(s)
- Jana Pourová
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Lenka Applová
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Kateřina Macáková
- Department of Pharmaceutical Botany, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Marie Vopršalová
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Thomas Migkos
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Roger Bentanachs
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
- Department of Pharmacology, Toxicology and Therapeutic Chemistry, School of Pharmacy and Food Science, University of Barcelona, Avda. Joan XXII 27-31, 08028 Barcelona, Spain.
| | - David Biedermann
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Lucie Petrásková
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Václav Tvrdý
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Marcel Hrubša
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Jana Karlíčková
- Department of Pharmaceutical Botany, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
| | - Vladimír Křen
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Kateřina Valentová
- Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague, Czech Republic.
| | - Přemysl Mladěnka
- Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Králové, Charles University, Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
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13
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Bijak M. Silybin, a Major Bioactive Component of Milk Thistle (Silybum marianum L. Gaernt.)-Chemistry, Bioavailability, and Metabolism. Molecules 2017; 22:E1942. [PMID: 29125572 PMCID: PMC6150307 DOI: 10.3390/molecules22111942] [Citation(s) in RCA: 167] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 10/28/2017] [Accepted: 11/08/2017] [Indexed: 01/04/2023] Open
Abstract
Milk thistle (Silybum marianum) is a medicinal plant that has been used for thousands of years as a remedy for a variety of ailments. The main component of S. marianum fruit extract (silymarin) is a flavonolignan called silybin, which is not only the major silymarin element but is also the most active ingredient of this extract, which has been confirmed in various studies. This compound belongs to the flavonoid group known as flavonolignans. Silybin's structure consists in two main units. The first is based on a taxifolin, the second a phenyllpropanoid unit, which in this case is conyferil alcohol. These two units are linked together into one structure by an oxeran ring. Since the 1970s, silybin has been regarded in official medicine as a substance with hepatoprotective properties. There is a large body of research that demonstrates silybin's many other healthy properties, but there are still a lack of papers focused on its molecular structure, chemistry, metabolism, and novel form of administration. Therefore, the aim of this paper is a literature review presenting and systematizing our knowledge of the silybin molecule, with particular emphasis on its structure, chemistry, bioavailability, and metabolism.
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Affiliation(s)
- Michal Bijak
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
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14
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Albassam AA, Frye RF, Markowitz JS. The effect of milk thistle (Silybum marianum) and its main flavonolignans on CYP2C8 enzyme activity in human liver microsomes. Chem Biol Interact 2017; 271:24-29. [PMID: 28457856 DOI: 10.1016/j.cbi.2017.04.025] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 04/27/2017] [Indexed: 01/04/2023]
Abstract
Milk thistle is a widely-consumed botanical used for an array of purported health benefits. The primary extract of milk thistle is termed silymarin, a complex mixture that contains a number of structurally-related flavonolignans, the flavonoid, taxifolin, and a number of other constituents. The major flavonolignans present in most extracts are silybin A, silybin B, isosilybin A and isosilybin B, silydianin, silychristin and isosilychristin. Silymarin itself has been reported to inhibit CYP2C8 activity in vitro, but the effect of the individual flavonolignans on this enzyme has not been studied. To investigate the effects of milk thistle extract and its main flavonolignans (silybin A, silybin B, isosilybin A and isosilybin B) on CYP2C8 activity at relevant concentrations, the effect of milk thistle extract and the flavonolignans on CYP2C8 enzyme activity was studied in vitro using human liver microsomes (HLM) incorporating an enzyme-selective substrate for CYP2C8, amodiaquine. Metabolite formation was analyzed using liquid chromatography-tandem mass spectrometry (LC/MS-MS). The concentration causing 50% inhibition of enzyme activity (IC50) was used to express the degree of inhibition. Isosilibinin, a mixture of the diastereoisomers isosilybin A and isosilybin B, was found to be the most potent inhibitor, followed by isosilybin B with IC50 values (mean ± SE) of 1.64 ± 0.66 μg/mL and 2.67 ± 1.18 μg/mL, respectively. The rank order of observed inhibitory potency after isosilibinin was silibinin > isosilybin A > silybin A > milk thistle extract > and silybin B. These in vitro results suggest a potentially significant inhibitory effect of isosilibinin and isosilybin B on CYP2C8 activity. However, the observed IC50 values are unlikely to be achieved in humans supplemented with orally administered milk thistle extracts due to the poor bioavailability of flavonolignans documented with most commercially available formulations.
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Affiliation(s)
- Ahmed A Albassam
- Department of Pharmacotherapy and Translational Research, University of Florida College of Pharmacy, Gainesville, FL, USA; Department of Clinical Pharmacy, College of Pharmacy, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia.
| | - Reginald F Frye
- Department of Pharmacotherapy and Translational Research, University of Florida College of Pharmacy, Gainesville, FL, USA
| | - John S Markowitz
- Department of Pharmacotherapy and Translational Research, University of Florida College of Pharmacy, Gainesville, FL, USA
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15
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Xie Y, Miranda SR, Hoskins JM, Hawke RL. Role of UDP-Glucuronosyltransferase 1A1 in the Metabolism and Pharmacokinetics of Silymarin Flavonolignans in Patients with HCV and NAFLD. Molecules 2017; 22:E142. [PMID: 28098838 PMCID: PMC6155777 DOI: 10.3390/molecules22010142] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2016] [Revised: 12/30/2016] [Accepted: 01/08/2017] [Indexed: 02/06/2023] Open
Abstract
Silymarin is the most commonly used herbal medicine by patients with chronic liver disease. Silymarin flavonolignans undergo rapid first-pass metabolism primarily by glucuronidation. The aims of this investigation were: (1) to determine the association of UGT1A1*28 polymorphism with the area under the plasma concentration-time curves (AUCs) for silybin A (SA) and silybin B (SB); (2) to evaluate the effect of UGT1A1*28 polymorphism on the profile of flavonolignan glucuronide conjugates found in the plasma; and (3) to investigate the role of UGT1A1 enzyme kinetics on the pharmacokinetics of SA and SB. AUCs and metabolic ratios for thirty-three patients with chronic liver disease administered oral doses of silymarin were compared between different UGT1A1*28 genotypes. The AUCs, metabolic ratios, and the profiles of major SA and SB glucuronides did not differ significantly among the three UGT1A1 genotypes. In contrast, an increase in the proportion of sulfated flavonolignan conjugates in plasma was observed in subjects with UGT1A1*28/*28 genotype compared to subjects carrying wild type alleles. Differences in SA and SB in vitro intrinsic clearance estimates for UGTIA1 correlated inversely with SA and SB exposures observed in vivo indicating a major role for UGT1A1 in silymarin metabolism. In addition, a significant difference in the metabolic ratio observed between patients with NAFLD and HCV suggests that any effect of UGT1A1 polymorphism may be obscured by a greater effect of liver disease on the pharmacokinetics of silymarin. Taken together, these results suggest the presence of the UGT1A1*28 allele does not contribute significantly to a large inter-subject variability in the pharmacokinetics of silybin A and silybin B which may obscure the ability to detect beneficial effects of silymarin in patients with liver disease.
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Affiliation(s)
- Ying Xie
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
- State Key Laboratory for Quality Research of Chinese Medicines, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau, China.
| | - Sonia R Miranda
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Janelle M Hoskins
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
| | - Roy L Hawke
- Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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16
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Gufford BT, Graf TN, Paguigan ND, Oberlies NH, Paine MF. Chemoenzymatic Synthesis, Characterization, and Scale-Up of Milk Thistle Flavonolignan Glucuronides. Drug Metab Dispos 2015; 43:1734-43. [PMID: 26316643 PMCID: PMC4613946 DOI: 10.1124/dmd.115.066076] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 08/26/2015] [Indexed: 11/22/2022] Open
Abstract
Plant-based therapeutics, including herbal products, continue to represent a growing facet of the contemporary health care market. Mechanistic descriptions of the pharmacokinetics and pharmacodynamics of constituents composing these products remain nascent, particularly for metabolites produced following herbal product ingestion. Generation and characterization of authentic metabolite standards are essential to improve the quantitative mechanistic understanding of herbal product disposition in both in vitro and in vivo systems. Using the model herbal product, milk thistle, the objective of this work was to biosynthesize multimilligram quantities of glucuronides of select constituents (flavonolignans) to fill multiple knowledge gaps in the understanding of herbal product disposition and action. A partnership between clinical pharmacology and natural products chemistry expertise was leveraged to optimize reaction conditions for efficient glucuronide formation and evaluate alternate enzyme and reagent sources to improve cost effectiveness. Optimized reaction conditions used at least one-fourth the amount of microsomal protein (from bovine liver) and cofactor (UDP glucuronic acid) compared with typical conditions using human-derived subcellular fractions, providing substantial cost savings. Glucuronidation was flavonolignan-dependent. Silybin A, silybin B, isosilybin A, and isosilybin B generated five, four, four, and three monoglucuronides, respectively. Large-scale synthesis (40 mg of starting material) generated three glucuronides of silybin A: silybin A-7-O-β-D-glucuronide (15.7 mg), silybin A-5-O-β-D-glucuronide (1.6 mg), and silybin A-4´´-O-β-D-glucuronide (11.1 mg). This optimized, cost-efficient method lays the foundation for a systematic approach to synthesize and characterize herbal product constituent glucuronides, enabling an improved understanding of mechanisms underlying herbal product disposition and action.
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Affiliation(s)
- Brandon T Gufford
- Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington (B.T.G., M.F.P.); and Department of Chemistry and Biochemistry, The University of North Carolina at Greensboro, Greensboro, North Carolina (T.N.G., N.D.P., N.H.O.)
| | - Tyler N Graf
- Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington (B.T.G., M.F.P.); and Department of Chemistry and Biochemistry, The University of North Carolina at Greensboro, Greensboro, North Carolina (T.N.G., N.D.P., N.H.O.)
| | - Noemi D Paguigan
- Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington (B.T.G., M.F.P.); and Department of Chemistry and Biochemistry, The University of North Carolina at Greensboro, Greensboro, North Carolina (T.N.G., N.D.P., N.H.O.)
| | - Nicholas H Oberlies
- Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington (B.T.G., M.F.P.); and Department of Chemistry and Biochemistry, The University of North Carolina at Greensboro, Greensboro, North Carolina (T.N.G., N.D.P., N.H.O.)
| | - Mary F Paine
- Experimental and Systems Pharmacology, College of Pharmacy, Washington State University, Spokane, Washington (B.T.G., M.F.P.); and Department of Chemistry and Biochemistry, The University of North Carolina at Greensboro, Greensboro, North Carolina (T.N.G., N.D.P., N.H.O.)
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17
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Marhol P, Bednář P, Kolářová P, Večeřa R, Ulrichová J, Tesařová E, Vavříková E, Kuzma M, Křen V. Pharmacokinetics of pure silybin diastereoisomers and identification of their metabolites in rat plasma. J Funct Foods 2015. [DOI: 10.1016/j.jff.2015.02.031] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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18
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Silymarin as a Natural Antioxidant: An Overview of the Current Evidence and Perspectives. Antioxidants (Basel) 2015; 4:204-47. [PMID: 26785346 PMCID: PMC4665566 DOI: 10.3390/antiox4010204] [Citation(s) in RCA: 305] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2015] [Revised: 02/06/2015] [Accepted: 03/09/2015] [Indexed: 12/16/2022] Open
Abstract
Silymarin (SM), an extract from the Silybum marianum (milk thistle) plant containing various flavonolignans (with silybin being the major one), has received a tremendous amount of attention over the last decade as a herbal remedy for liver treatment. In many cases, the antioxidant properties of SM are considered to be responsible for its protective actions. Possible antioxidant mechanisms of SM are evaluated in this review. (1) Direct scavenging free radicals and chelating free Fe and Cu are mainly effective in the gut. (2) Preventing free radical formation by inhibiting specific ROS-producing enzymes, or improving an integrity of mitochondria in stress conditions, are of great importance. (3) Maintaining an optimal redox balance in the cell by activating a range of antioxidant enzymes and non-enzymatic antioxidants, mainly via Nrf2 activation is probably the main driving force of antioxidant (AO) action of SM. (4) Decreasing inflammatory responses by inhibiting NF-κB pathways is an emerging mechanism of SM protective effects in liver toxicity and various liver diseases. (5) Activating vitagenes, responsible for synthesis of protective molecules, including heat shock proteins (HSPs), thioredoxin and sirtuins and providing additional protection in stress conditions deserves more attention. (6) Affecting the microenvironment of the gut, including SM-bacteria interactions, awaits future investigations. (7) In animal nutrition and disease prevention strategy, SM alone, or in combination with other hepatho-active compounds (carnitine, betaine, vitamin B12, etc.), might have similar hepatoprotective effects as described in human nutrition.
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Abstract
Silybin, a secondary metabolite isolated from the seeds of the blessed milk thistle (Silybum marianum) was discovered as the first member of a new family of natural compounds called flavonolignans in 1959. Over the years it has received the research attention of many organic chemists. This research has resulted in a number of semisynthetic derivatives prepared in an effort to modulate and better target the biological activities of silybin or to improve its physical properties, such as its solubility. A fundamental breakthrough in silybin chemistry was the determination of the absolute configurations of silybin A and silybin B, and the development of methods for their separation. This review covers articles dealing with silybin chemistry and also summarizes all the derivatives prepared.
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Affiliation(s)
- D Biedermann
- Institute of Microbiology AS CR, Centre of Biocatalysis and Biotransformation, Vídeňská 1083, Prague 4, CZ 14220, Czech Republic.
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20
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Charrier C, Azerad R, Marhol P, Purchartová K, Kuzma M, Křen V. Preparation of silybin phase II metabolites: Streptomyces catalyzed glucuronidation. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.molcatb.2014.02.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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Zenger K, Chen X, Decker M, Kraus B. In-vitro stability and metabolism of a tacrine–silibinin codrug. J Pharm Pharmacol 2013; 65:1765-72. [DOI: 10.1111/jphp.12070] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Accepted: 03/25/2013] [Indexed: 12/01/2022]
Abstract
Abstract
Objectives
A tacrine-silibinin codrug showed promising results in pharmacological and toxicity testing, superior to an equimolar mixture of tacrine and silibinin. The aim of this study was to get more information about its stability, possible degradation products, metabolites, and especially its active principle in vitro and in vivo.
Methods
The stability of the codrug was analysed under in-vitro assay conditions. Additionally, its metabolism was investigated using pooled human liver microsomes. Metabolites were identified via liquid chromatography-high resolution electrospray ionization mass spectrometry. Furthermore, the influence of one of the main cleavage products, tacrine hemi succinamide, on viability and mitochondria of hepatic stellate cells was analysed.
Key findings
The codrug remained stable in culture medium (Dulbecco's modified Eagle's medium) over an incubation period of 24 h, whereas exposition to microsomal enzymes led to rapid cleavage of the ester bond to form silibinin and a tacrine hemi succinamide. In addition, glucuronidated metabolites of both silibinin and the codrug were detected. For the tacrine hemi succinamide, no effects were observed with regard to cell viability and mitochondrial impairment.
Conclusions
This study helps understand and interpret previous results concerning the effects and the absence of toxicity of the tacrine–silibinin codrug and supplies important information for further identification of the active principles of the codrug in vivo.
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Affiliation(s)
- Katharina Zenger
- Institut für Pharmazie, Universität Regensburg, Regensburg, Germany
| | - Xinyu Chen
- Institut für Pharmazie, Universität Regensburg, Regensburg, Germany
- Institut für Pharmazie und Lebensmittelchemie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Michael Decker
- Institut für Pharmazie, Universität Regensburg, Regensburg, Germany
- Institut für Pharmazie und Lebensmittelchemie, Julius-Maximilians-Universität Würzburg, Würzburg, Germany
| | - Birgit Kraus
- Institut für Pharmazie, Universität Regensburg, Regensburg, Germany
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22
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Jančová P, Siller M, Anzenbacherová E, Křen V, Anzenbacher P, Simánek V. Evidence for differences in regioselective and stereoselective glucuronidation of silybin diastereomers from milk thistle (Silybum marianum) by human UDP-glucuronosyltransferases. Xenobiotica 2011; 41:743-51. [PMID: 21524189 DOI: 10.3109/00498254.2011.573017] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The flavonolignan silybin, the main component of silymarin, extract from the seeds of Silybum marianum, is used mostly as a hepatoprotectant. Silybin is almost 1:1 mixture of two diastereomers A and B. The individual UDP-glucuronosyltransferases (UGTs) contributing to the metabolism of silybin diastereomers have not been identified yet. In this study, the contribution of UGTs to silybin metabolism was examined. The potential silybin metabolites were formed in vitro by incubating silybin (i) with the human liver microsomal fraction, (ii) with human hepatocytes and finally (iii) with 12 recombinant UGTs (UGT1A1, 1A3, 1A4, 1A6, 1A7, 1A8, 1A9, 1A10, 2B4, 2B7, 2B15 and 2B17). High-performance liquid chromatographic (HPLC) techniques with UV detection and additionally MS detection were used for metabolite identification. Hepatocytes and microsomes formed silybin A-7-O-β-D-glucuronides, B-7-O-β-D-glucuronides, A-20-O-β-D-glucuronides and B-20-O-β-D-glucuronides. With recombinant UGTs, the major role of the UGT1A1, 1A3, 1A8 and 1A10 enzymes but also of the UGT1A6, 1A7, 1A9, 2B7 and 2B15 in the stereoselective reactions leading to the respective silybin glucuronides was confirmed. UGT1A4, UGT2B4 and UGT2B17 did not participate in silybin glucuronidation. The predominant formation of 7-O-β-D-glucuronides and the preferential glucuronidation of silybin B diastereomer in vitro by human UGTs were confirmed.
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Affiliation(s)
- Petra Jančová
- Department of Medical Chemistry and Biochemistry, Faculty of Medicine and Dentistry, Palacky University, Olomouc, Czech Republic
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23
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Loguercio C, Festi D. Silybin and the liver: From basic research to clinical practice. World J Gastroenterol 2011; 17:2288-301. [PMID: 21633595 PMCID: PMC3098397 DOI: 10.3748/wjg.v17.i18.2288] [Citation(s) in RCA: 223] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 12/23/2010] [Accepted: 12/30/2010] [Indexed: 02/06/2023] Open
Abstract
Herbal products are increasingly used, mainly in chronic liver disease. Extracts of milk thistle, Silymarin and silybin, are the most prescribed natural compounds, with different indications, but with no definitive results in terms of clinical efficacy. This review analyzes the available studies on the effects of the purified product silybin, both as a free and a conjugated molecule, on liver cells or on experimentally induced liver damage, and in patients with liver disease. We searched PUBMED for articles pertaining to the in vitro and in vivo effects of silybin, its antifibrotic, anti-inflammatory, and antioxidant properties, as well as its metabolic effects, combined with the authors’ own knowledge of the literature. Results indicate that the bioavailability of silybin phytosome is higher than that of silymarin and is less influenced by liver damage; silybin does not show significant interactions with other drugs and at doses < 10 g/d has no significant side effects. Experimental studies have clearly demonstrated the antifibrotic, antioxidant and metabolic effects of silybin; previous human studies were insufficient for confirming the clinical efficacy in chronic liver disease, while ongoing clinical trials are promising. On the basis of literature data, silybin seems a promising drug for chronic liver disease.
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24
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Bannwart CF, Peraçoli JC, Nakaira-Takahagi E, Peraçoli MTS. Inhibitory effect of silibinin on tumour necrosis factor-alpha and hydrogen peroxide production by human monocytes. Nat Prod Res 2010; 24:1747-57. [PMID: 20981616 DOI: 10.1080/14786410903314492] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Silibinin is a chemically defined flavonoid and the main active component of silymarin, a polyphenolic complex from Silybum marianum, which has anti-inflammatory, hepatoprotective and anticarcinogenic properties. Monocytes obtained from healthy individuals were incubated with silibinin to evaluate cell viability, hydrogen peroxide (H(2)O(2)) release and tumour necrosis factor-alpha (TNF-α) production by these cells. The duration of treatment and different silibinin concentrations had no significant effect on cell viability. Monocytes showed a dose-dependent inhibitory effect on H(2)O(2) release by phorbol myristate acetate-stimulated monocytes in silibinin concentrations ranging from 6.25 to 50 µg mL(-1). Significant inhibition of TNF-α production by lipopolysaccharide-stimulated monocytes was observed at concentrations of 12.5, 50 and 100 µg mL(-1) of silibinin. These results suggest that silibinin exerts antioxidant and anti-inflammatory properties on human monocytes through an inhibitory effect on H(2)O(2) release and on TNF-α production, respectively.
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Affiliation(s)
- C F Bannwart
- Department of Microbiology and Immunology, Biosciences Institute, São Paulo State University, Botucatu, SP, Brazil
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25
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Parveen R, Ahmad S, Baboota S, Ali J, Alka A. Stability-indicating HPTLC method for quantitative estimation of silybin in bulk drug and pharmaceutical dosage form. Biomed Chromatogr 2010; 24:639-47. [PMID: 19816854 DOI: 10.1002/bmc.1340] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In the present study a novel stability-indicating high-performance thin-layer chromatography (HPTLC) method for quantitative determination of silybin in bulk drug and nanoemulsion formulation has been developed and validated on silica using solvent chloroform-acetone-formic acid (9 : 2 : 1 v/v/v) (R(f )of silybin 0.46 +/- 0.05) in the absorbance mode at 296 nm. The method showed a good linear relationship (r(2) +/- 0.999) in the concentration range 25-1500 ng per spot. It was found to be linear, accurate, precise, specific, robust and stability-indicating and can be applied for quality control and standardization of several multi-component hepatoprotective formulations as well as for stability testing of different dosage forms. The method proposed was also used to investigate the kinetics of acidic and alkaline degradation processes by quantification of drug at different temperature to calculate the activation energy and half-life for silymarin degradation.
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Affiliation(s)
- Rabea Parveen
- Department of Pharmaceutics, Faculty of Pharmacy, Hamdard University, New Delhi 110062, India
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26
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Hawke RL, Schrieber SJ, Soule TA, Wen Z, Smith PC, Reddy KR, Wahed AS, Belle SH, Afdhal NH, Navarro VJ, Berman J, Liu QY, Doo E, Fried MW. Silymarin ascending multiple oral dosing phase I study in noncirrhotic patients with chronic hepatitis C. J Clin Pharmacol 2009; 50:434-49. [PMID: 19841158 DOI: 10.1177/0091270009347475] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Silymarin, derived from the milk thistle plant Silybum marianum, is widely used for self-treatment of liver diseases, including hepatitis C virus (HCV), and its antiviral activity has been demonstrated in vitro and in HCV patients administered an intravenous formulation of the major silymarin flavonolignans, silybin A and silybin B. The safety and dose-exposure relationships of higher than customary oral doses of silymarin and its acute effects on serum HCV RNA were evaluated in noncirrhotic HCV patients. Four cohorts of 8 patients with well-compensated, chronic noncirrhotic HCV who failed interferon-based therapy were randomized 3:1 to silymarin or placebo. Oral doses of 140, 280, 560, or 700 mg silymarin were administered every 8 hours for 7 days. Steady-state exposures for silybin A and silybin B increased 11-fold and 38-fold, respectively, with a 5-fold increase in dose, suggesting nonlinear pharmacokinetics. No drug-related adverse events were reported, and no clinically meaningful reductions from baseline serum transaminases or HCV RNA titer were observed. Oral doses of silymarin up to 2.1 g per day were safe and well tolerated. The nonlinear pharmacokinetics of silybin A and silybin B suggests low bioavailability associated with customary doses of silymarin may be overcome with doses above 700 mg.
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Affiliation(s)
- Roy L Hawke
- Clinical Assistant Division of Pharmacotherapy and Experimental Therapeutics, UNC Eshelman School of Pharmacy, CB #7360, Kerr Hall Rm 3310, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7360, USA.
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27
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Wu JW, Lin LC, Tsai TH. Drug-drug interactions of silymarin on the perspective of pharmacokinetics. JOURNAL OF ETHNOPHARMACOLOGY 2009; 121:185-93. [PMID: 19041708 DOI: 10.1016/j.jep.2008.10.036] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2008] [Revised: 10/21/2008] [Accepted: 10/30/2008] [Indexed: 05/27/2023]
Abstract
Silymarin, which is extracted from the milk thistle (Silybum marianum), has been used for centuries for treating hepatic disorders and its hepatoprotective effects have been known for hundreds of years. Silymarin is a mixture of polyphenoic flavonoids, which include silibinin (silybin A and silybin B), isosilyin A and B, silychristin A and B, silydianin and other phenol compounds. The pharmacokinetics of silibinin shows fast absorption and elimination. Silymarin undergoes phase I and phase II metabolism, especially phase II conjugation reactions, it undergoes multiple conjugation reactions, and is primarily excreted into bile and urine. Silymarin has a good safety profile, but little is known regarding its potential for drug interaction. Silymarin has limited effect on the pharmacokinetics of several drugs in vivo; despite silymarin decreasing the activity of cytochrome P-450 (CYPs) enzymes, UDP-glucuronosyltransferase (UGT) enzyme, and reducing P-glycoprotein (P-gp) transport. Health-care practitioners should caution patients against co-administration of silymarin and pharmaceutical drugs.
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Affiliation(s)
- Jhy-Wen Wu
- Centers for Disease Control, Department of Health, Taipei, Taiwan
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28
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Chen Y, Xie S, Chen S, Zeng S. Glucuronidation of flavonoids by recombinant UGT1A3 and UGT1A9. Biochem Pharmacol 2008; 76:416-25. [DOI: 10.1016/j.bcp.2008.05.007] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2008] [Revised: 05/05/2008] [Accepted: 05/07/2008] [Indexed: 11/25/2022]
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29
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Wen Z, Dumas TE, Schrieber SJ, Hawke RL, Fried MW, Smith PC. Pharmacokinetics and metabolic profile of free, conjugated, and total silymarin flavonolignans in human plasma after oral administration of milk thistle extract. Drug Metab Dispos 2008; 36:65-72. [PMID: 17913795 DOI: 10.1124/dmd.107.017566] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Silymarin, a mixture of polyphenolic flavonoids extracted from milk thistle (Silybum marianum), is composed mainly of silychristin, silydianin, silybin A, silybin B (SB(B)), isosilybin A (ISB(A)), and isosilybin B. In this study, the plasma concentrations of free (unconjugated), conjugated (sulfated and glucuronidated), and total (free and conjugated) silymarin flavonolignans were measured using liquid chromatography-electrospray ionization-mass spectrometry, after a single oral dose of 600 mg of standardized milk thistle extracts to three healthy volunteers. Pharmacokinetic analysis indicated that silymarin flavonolignans were rapidly eliminated with short half-lives (1-3 and 3-8 h for free and conjugated, respectively). The AUC(0-->infinity) values of the conjugated silymarin flavonolignans were 4- to 30-fold higher than those of their free fractions, with SB(B) (mean AUC(0-->infinity) = 51 and 597 microg x h/l for free and conjugated, respectively) and ISB(A) (mean AUC(0-->infinity) = 30 and 734 microg x h/l for free and conjugated, respectively) exhibiting higher AUC(0-->infinity) values in comparison with other flavonolignans. Near the plasma peak times (1-3 h), the free, sulfated, and glucuronidated flavonolignans represented approximately 17, 28, and 55% of the total silymarin, respectively. In addition, the individual silymarin flavonolignans exhibited quite different plasma profiles for both the free and conjugated fractions. These data suggest that, after oral administration, silymarin flavonolignans are quickly metabolized to their conjugates, primarily forming glucuronides, and the conjugates are primary components present in human plasma.
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Affiliation(s)
- Zhiming Wen
- School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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30
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Kroll DJ, Shaw HS, Oberlies NH. Milk thistle nomenclature: why it matters in cancer research and pharmacokinetic studies. Integr Cancer Ther 2007; 6:110-9. [PMID: 17548790 DOI: 10.1177/1534735407301825] [Citation(s) in RCA: 155] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Extracts of milk thistle have been recognized for centuries as "liver tonics" and are well-known to prevent or reverse hepatotoxicity of reactive drug metabolites or naturally occurring toxins. Milk thistle extracts are now under intense study in the experimental therapeutics of cancer for chemoprevention, treatment, and amelioration of chemotherapy side effects. Precision in nomenclature, however, has lagged behind this progress. The crude commercial product of milk thistle is termed silymarin, a complex of at least 7 flavonolignans and 1 flavonoid that comprises 65% to 80% of milk thistle extract. From silymarin is derived silibinin, a semipurified fraction once thought to be a single compound but now recognized as a 1:1 mixture of 2 diastereoisomers, silybin A and silybin B. The distinction between silymarin and silibinin is not only important to understanding the historical literature, but thorough characterization and use of chemically defined mixtures in preclinical and clinical studies are essential to the progress of these botanical compounds as human therapeutics. As a result, we urge clinicians and preclinical investigators alike to exercise rigor in nomenclature and use pure compounds or precisely defined chemical mixtures in subsequent studies. Herein, we provide a guide to the proper nomenclature and composition of milk thistle extracts and discuss the known pharmacokinetic studies of these botanical medicines. The drug-interaction potential of these extracts appears to be quite low, and in fact, silibinin appears to synergize with the antitumor effects of some commonly used chemotherapeutics. However, some precautions are advised as high-dose, phase II studies are conducted.
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Affiliation(s)
- David J Kroll
- Natural Products Laboratory, Research Triangle Institute (RTI), Research Triangle Park, NC 27709-2194, USA.
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31
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Kim HJ, Park HS, Lee IS. Microbial transformation of silybin by Trichoderma koningii. Bioorg Med Chem Lett 2006; 16:790-3. [PMID: 16309908 DOI: 10.1016/j.bmcl.2005.11.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2005] [Revised: 10/29/2005] [Accepted: 11/08/2005] [Indexed: 11/29/2022]
Abstract
Microbial transformation of silybin A (1) and silybin B (2), the major hepatoprotective flavonolignan diastereomers from the fruits of Silybum marianum, with the culture broth of Trichoderma koningii gave two pairs of glucosylated derivatives. Their structures were identified as silybin A 3-O-beta-D-glucopyranoside (3), silybin A 7-O-beta-D-glucopyranoside (4), silybin B 3-O-beta-D-glucopyranoside (5) and silybin B 7-O-beta-D-glucopyranoside (6) by spectroscopic methods.
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Affiliation(s)
- Hyun Jung Kim
- College of Pharmacy and Research Institute of Drug Development, Chonnam National University, Gwangju 500-757, Republic of Korea
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32
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Venkataramanan R, Komoroski B, Strom S. In vitro and in vivo assessment of herb drug interactions. Life Sci 2006; 78:2105-15. [PMID: 16427092 DOI: 10.1016/j.lfs.2005.12.021] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2005] [Accepted: 12/07/2005] [Indexed: 12/12/2022]
Abstract
Herbal products contain several chemicals that are metabolized by phase 1 and phase 2 pathways and also serve as substrates for certain transporters. Due to their interaction with these enzymes and transporters there is a potential for alteration in the activity of drug metabolizing enzymes and transporters in presence of herbal components. Induction and inhibition of drug metabolizing enzymes and transporters by herbal component has been documented in several in vitro studies. While these studies offer a system to determine the potential for a herbal component to alter the pharmacokinetics of a drug, they cannot always be used to predict the magnitude of any potential effect in vivo. In vivo studies are the ultimate way to determine the clinical importance of herb drug interactions. However, lack of content uniformity and lack of documentation of the bioavailability of herbal components makes even in vivo human studies difficult to interpret as the effect may be product specific. It appears that St. John's wort extract is probably one of the most important herbal product that increases the metabolism and decreases the efficacy of several drugs. Milk thistle on the other hand appears to have minimal effect on phase 1 pathways and limited data exists for phase 2 pathways and transporter activity in vivo. Further systematic studies are necessary to assess the significance of herb drug interactions.
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Affiliation(s)
- Raman Venkataramanan
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Pittsburgh, Pittsburgh PA 15261, USA.
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van Erp NPH, Baker SD, Zhao M, Rudek MA, Guchelaar HJ, Nortier JWR, Sparreboom A, Gelderblom H. Effect of milk thistle (Silybum marianum) on the pharmacokinetics of irinotecan. Clin Cancer Res 2005; 11:7800-6. [PMID: 16278402 DOI: 10.1158/1078-0432.ccr-05-1288] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Milk thistle (Silybum marianum) is one of the most commonly used herbal therapies, and its principal constituent silybin significantly inhibits cytochrome P450 isoform 3A4 (CYP3A4) and UDP glucuronosyltransferase isoform 1A1 (UGT1A1) in vitro. Here, we investigated whether milk thistle affects the pharmacokinetics of irinotecan, a substrate for CYP3A4 and UGT1A1, in humans. EXPERIMENTAL DESIGN Six cancer patients were treated with irinotecan (dose, 125 mg/m(2)) given as a 90-minute infusion once every week. Four days before the second dose, patients received 200 mg milk thistle, thrice a day, for 14 consecutive days. Pharmacokinetic studies of irinotecan and its metabolites 7-ethyl-10-hydroxycamptothecin (SN-38), 7-ethyl-10-[3,4,5-trihydroxy-pyran-2-carboxylic acid]-camptothecin (SN-38-glucuronide), and 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidino]-carbonyloxycamptothecin were done during the first three irinotecan administrations. RESULTS Short-term (4 days) or more prolonged intake of milk thistle (12 days) had no significant effect on irinotecan clearance (mean, 31.2 versus 25.4 versus 25.6 L/h; P = 0.16). The area under the curve ratio of SN-38 and irinotecan was slightly decreased by milk thistle (2.58% versus 2.23% versus 2.17%; P = 0.047), whereas the relative extent of glucuronidation of SN-38 was similar (10.8 versus 13.5 versus 13.1; P = 0.64). Likewise, the area under the curve ratio of 7-ethyl-10-[4-N-(5-aminopentanoic acid)-1-piperidino]-carbonyloxycamptothecin and irinotecan was unaffected by milk thistle (0.332 versus 0.285 versus 0.337; P = 0.53). The maximum plasma concentrations of silybin ranged between 0.0249 and 0.257 micromol/L. CONCLUSIONS Silybin concentrations after intake of milk thistle are too low to significantly affect the function of CYP3A4 and UGT1A1 in vivo, indicating that milk thistle is unlikely to alter the disposition of anticancer drugs metabolized by these enzymes.
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Affiliation(s)
- Nielka P H van Erp
- Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, the Netherlands
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