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Mathomes RT, Koulas SM, Tsialtas I, Stravodimos G, Welsby PJ, Psarra AMG, Stasik I, Leonidas DD, Hayes JM. Multidisciplinary docking, kinetics and X-ray crystallography studies of baicalein acting as a glycogen phosphorylase inhibitor and determination of its' potential against glioblastoma in cellular models. Chem Biol Interact 2023; 382:110568. [PMID: 37277066 DOI: 10.1016/j.cbi.2023.110568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/19/2023] [Accepted: 05/24/2023] [Indexed: 06/07/2023]
Abstract
Glycogen phosphorylase (GP) is the rate-determining enzyme in the glycogenolysis pathway. Glioblastoma (GBM) is amongst the most aggressive cancers of the central nervous system. The role of GP and glycogen metabolism in the context of cancer cell metabolic reprogramming is recognised, so that GP inhibitors may have potential treatment benefits. Here, baicalein (5,6,7-trihydroxyflavone) is studied as a GP inhibitor, and for its effects on glycogenolysis and GBM at the cellular level. The compound is revealed as a potent GP inhibitor against human brain GPa (Ki = 32.54 μM), human liver GPa (Ki = 8.77 μM) and rabbit muscle GPb (Ki = 5.66 μM) isoforms. It is also an effective inhibitor of glycogenolysis (IC50 = 119.6 μM), measured in HepG2 cells. Most significantly, baicalein demonstrated anti-cancer potential through concentration- and time-dependent decrease in cell viability for three GBM cell-lines (U-251 MG, U-87 MG, T98-G) with IC50 values of ∼20-55 μM (48- and 72-h). Its effectiveness against T98-G suggests potential against GBM with resistance to temozolomide (the first-line therapy) due to a positive O6-methylguanine-DNA methyltransferase (MGMT) status. The solved X-ray structure of rabbit muscle GP-baicalein complex will facilitate structure-based design of GP inhibitors. Further exploration of baicalein and other GP inhibitors with different isoform specificities against GBM is suggested.
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Affiliation(s)
- Rachel T Mathomes
- School of Pharmacy & Biomedical Sciences, University of Central Lancashire, Preston, PR1 2HE, United Kingdom
| | - Symeon M Koulas
- Department of Biochemistry & Biotechnology, University of Thessaly, Biopolis, 41500, Larissa, Greece
| | - Ioannis Tsialtas
- Department of Biochemistry & Biotechnology, University of Thessaly, Biopolis, 41500, Larissa, Greece
| | - George Stravodimos
- Department of Biochemistry & Biotechnology, University of Thessaly, Biopolis, 41500, Larissa, Greece
| | - Philip J Welsby
- Department of Postgraduate Medical Education, Edge Hill University, Ormskirk, L39 4QP, United Kingdom
| | - Anna-Maria G Psarra
- Department of Biochemistry & Biotechnology, University of Thessaly, Biopolis, 41500, Larissa, Greece
| | - Izabela Stasik
- School of Pharmacy & Biomedical Sciences, University of Central Lancashire, Preston, PR1 2HE, United Kingdom
| | - Demetres D Leonidas
- Department of Biochemistry & Biotechnology, University of Thessaly, Biopolis, 41500, Larissa, Greece.
| | - Joseph M Hayes
- School of Pharmacy & Biomedical Sciences, University of Central Lancashire, Preston, PR1 2HE, United Kingdom.
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Ahmad S, Rafiq H, Khan A, Tikmani P, Batool Z, Tabassum S, Arain F, Siddiqi S, Khaliq S, Amin F, Wasim M, Haider S. Ameliorative effects of half-dose saffron and chamomile combination on Psycho-endocrinological changes in a diabetic murine model. PLoS One 2022; 17:e0276236. [PMID: 36302045 PMCID: PMC9612524 DOI: 10.1371/journal.pone.0276236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 10/03/2022] [Indexed: 11/06/2022] Open
Abstract
INTRODUCTION Diabetes mellitus is a chronic metabolic disorder with an increasing prevalence worldwide. Reduction in blood insulin level alters brain function by inducing oxidative stress with changes in dopamine and norepinephrine neurotransmission, ultimately leading to neuropsychological symptoms. The efficacy of currently available psychotropic drugs is not satisfactory. Therefore, this study was conducted to explore the beneficial effects of a combination of the natural herbs, saffron and chamomile, in treating diabetes and its resultant neuropsychological effects using a rodent model of diabetes mellitus. METHOD The rats were randomly divided in to eight groups (n = 10), healthy control (HC), diabetic control (DC) and six groups of diabetic rats treated with various concentrations and combinations of saffron and chamomile. Diabetic treatment groups individually received methanolic extract and water decoction of chamomile (30 mg/kg) and saffron (10mg/kg) and their combined half doses (saffron 5mg/kg and chamomile 15mg/kg) for two weeks. Open field test (OFT) and forced swim test (FST) were used to measure the anxiolytic and antidepressant effects of herbs, respectively. Finally, biochemical, and neurochemical estimations were made. RESULTS The present study suggests the therapeutic effects of herbs especially in co-administrated decoction, against diabetes with improved antioxidant profile and enhanced levels of dopamine and norepinephrine. Anxiolytic and antidepressant effects were evident with improvements in the OFT and FST. Examination of the cortex of the diabetic group revealed cellular damage and tangle formation, which indicates advanced stages of dementia. CONCLUSION This study shows that the use of a combination of saffron and chamomile improves diabetes control and reduces its related psychiatric effects.
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Affiliation(s)
- Saara Ahmad
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
- * E-mail: ,
| | - Hamna Rafiq
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
| | - Asra Khan
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
| | - Prashant Tikmani
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
| | - Zehra Batool
- Dr Panjwani Center for Molecular Medicine and Drug Research, International Center for Chemical and Biological Sciences, University of Karachi, Karachi, Pakistan
| | - Saiqa Tabassum
- Department of Biosciences, Shaheed Zulfikar Ali Bhutto Institute of Science and Technology, Dubai, United Arab Emirates
| | - Fazal Arain
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
| | - Salman Siddiqi
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
| | - Saima Khaliq
- Department of Biochemistry, Federal Urdu University of Science, Arts and Technology, Karachi, Pakistan
| | - Faiq Amin
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
| | - Muhammad Wasim
- Department of Biological and Biomedical Sciences, The Aga Khan University, Karachi, Pakistan
| | - Saida Haider
- Department of Biochemistry, University of Karachi, Karachi, Pakistan
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Flavonoids as Antidiabetic and Anti-Inflammatory Agents: A Review on Structural Activity Relationship-Based Studies and Meta-Analysis. Int J Mol Sci 2022; 23:ijms232012605. [PMID: 36293459 PMCID: PMC9604264 DOI: 10.3390/ijms232012605] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 10/06/2022] [Accepted: 10/10/2022] [Indexed: 12/15/2022] Open
Abstract
Flavonoids are a group of naturally occurring polyphenolic secondary metabolites which have been reported to demonstrate a wide range of pharmacological properties, most importantly, antidiabetic and anti-inflammatory effects. The relationship between hyperglycaemia and inflammation and vascular complications in diabetes is now well established. Flavonoids possessing antidiabetic properties may alleviate inflammation by reducing hyperglycaemia through different mechanisms of action. It has been suggested that the flavonoids’ biochemical properties are structure-dependent; however, they are yet to be thoroughly grasped. Hence, the main aim of this review is to understand the antidiabetic and anti-inflammatory properties of various structurally diverse flavonoids and to identify key positions responsible for the effects, their correlation, and the effect of different substitutions on both antidiabetic and anti-inflammatory properties. The general requirement of flavonoids for exerting both anti-inflammatory and antidiabetic effects is found to be the presence of a C2–C3 double bond (C-ring) and hydroxyl groups at the C3’, C4’, C5, and C7 positions of both rings A and B of a flavonoid skeleton. Furthermore, it has been demonstrated that substitution at the C3 position of a C-ring decreases the anti-inflammatory action of flavonoids while enhancing their antidiabetic activity. Correlation is discussed at length to support flavonoids possessing essential pharmacophores to demonstrate equipotent effects. The consideration of these structural features may play an important role in synthesizing better flavonoid-based drugs possessing dual antidiabetic and anti-inflammatory effects. A meta-analysis further established the role of flavonoids as antidiabetic and anti-inflammatory agents.
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Flavones: Six Selected Flavones and Their Related Signaling Pathways That Induce Apoptosis in Cancer. Int J Mol Sci 2022; 23:ijms231810965. [PMID: 36142874 PMCID: PMC9505532 DOI: 10.3390/ijms231810965] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/18/2022] Open
Abstract
Cancer is a horrific disease that, to date, has no cure. It is caused by various factors and takes many lives. Apoptosis is a programmed cell death mechanism and if it does not function correctly in cancer cells, it can lead to severe disease. There are various signaling pathways for regulating apoptosis in cancer cells. Flavonoids are non-artificial natural bioactive compounds that are gaining attention as being capable of for inducing apoptosis in cancer cells. Among these, in this study, we focus on flavones. Flavones are a subclass of the numerous available flavonoids and possess several bioactive functions. Some of the most reported and well-known critical flavones, namely apigenin, acacetin, baicalein, luteolin, tangeretin, and wogonin, are discussed in depth in this review. Our main aim is to investigate the effects of the selected flavones on apoptosis and cell signaling pathways that contribute to death due to various types of cancers.
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Boshkayeva AK, Omarova RA, Ordabayeva SK, Serikbayeva AD, Umurzakhova GG, Massakbayev AJ. Modeling of the Structure and Forecasting Properties of Dihydroquercetin Derivatives. Drug Dev Ind Pharm 2022; 48:52-57. [PMID: 35748812 DOI: 10.1080/03639045.2022.2094398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIMS To study new chemical compounds with the potential cure proper, and to develop modifications of the preferred structure of dihydroquercetin. BACKGROUND Producing of the new drugs needs the study of the cure properties of the chemical composes first of all, and computer modeling can make this process more informative and easily. OBJECTIVE Computer projection of the chemical compounds potential cure properties. METHODS The reactivity of the studied models was evaluated by comparing the energies of the boundary molecular orbitals (HOMO and LUMO), as well as the difference in their values. The reaction center of the model molecules was determined via the analysis of the charge characteristics on atoms in each of them. RESULTS A theoretical model of new chemical compounds with the potential properties of drugs was substantiated and modifications of the preferred structure of dihydroquercetin have been developed. The concept of new compounds has been expanded and opportunities for the modification of compounds with high pharmacological activity have been discussed. Using the AM1, PM3, RM1 methods spatial characteristics were calculated. The results of quantum-chemical studies of model derivatives of dihydroquercetin via the RM1 method were carried out. CONCLUSIONS Calculation of the enthalpies of formation of model molecules allowed evaluating their thermodynamic stability. An analysis of the electric dipole moments made a possibility determining the preferred (polar) nature of the solvents for the studied model molecular systems.
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Affiliation(s)
- A K Boshkayeva
- Department of Pharmaceutical and Toxicological Chemistry, Pharmacognosy and Botany, Asfendiyarov Kazakh National Medical University, Almaty, Republic of Kazakhstan
| | - R A Omarova
- Department of engineering disciplines, Asfendiyarov Kazakh National Medical University, Almaty, Republic of Kazakhstan
| | - S K Ordabayeva
- Department of Pharmaceutical and Toxicological Chemistry, South Kazakhstan Medical Academy JSC, Shymkent, Republic of Kazakhstan
| | - A D Serikbayeva
- Department of Pharmaceutical and Toxicological Chemistry, South Kazakhstan Medical Academy JSC, Shymkent, Republic of Kazakhstan
| | - G G Umurzakhova
- Department of Organization and Management of Pharmaceutical Affairs, South Kazakhstan Medical Academy JSC, Shymkent, Republic of Kazakhstan
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Kim KH. Outliers in SAR and QSAR: 4. effects of allosteric protein-ligand interactions on the classical quantitative structure-activity relationships. Mol Divers 2022; 26:3057-3092. [PMID: 35192113 DOI: 10.1007/s11030-021-10365-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/10/2021] [Indexed: 11/26/2022]
Abstract
Effects of allosteric interactions on the classical structure-activity relationship (SAR) and quantitative SAR (QSAR) have been investigated. Apprehending the outliers in SAR and QSAR studies can improve the quality, predictability, and use of QSAR in designing unknown compounds in drug discovery research. We explored allosteric protein-ligand interactions as a possible source of outliers in SAR/QSAR. We used glycogen phosphorylase as an example of a protein that has an allosteric site. Examination of the ligand-bound x-ray crystal structures of glycogen phosphorylase revealed that many inhibitors bound at more than one binding site. The results of QSAR analyses of the inhibitors included a QSAR that recognized an outlier bound at a distinctive allosteric binding site. The case provided an example of constructive use of QSAR identifying outliers with alternative binding modes. Other allosteric QSARs that captured our attention were the inverted parabola/bilinear QSARs. The x-ray crystal structures and the QSAR analyses indicated that the inverted parabola QSARs could be associated with the conformational changes in the allosteric interactions. Our results showed that the normal parabola, as well as the inverted parabola QSARs, can describe the allosteric interactions. Examination of the ligand-bound X-ray crystal structures of glycogen phosphorylase revealed that many inhibitors bound at more than one binding site. The results of QSAR analyses of the inhibitors included a QSAR that recognized an outlier bound at a distinctive allosteric binding site.
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Rocha S, Aniceto N, Guedes RC, Albuquerque HMT, Silva VLM, Silva AMS, Corvo ML, Fernandes E, Freitas M. An In Silico and an In Vitro Inhibition Analysis of Glycogen Phosphorylase by Flavonoids, Styrylchromones, and Pyrazoles. Nutrients 2022; 14:nu14020306. [PMID: 35057487 PMCID: PMC8781192 DOI: 10.3390/nu14020306] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/03/2022] [Accepted: 01/05/2022] [Indexed: 02/01/2023] Open
Abstract
Glycogen phosphorylase (GP) is a key enzyme in the glycogenolysis pathway. GP inhibitors are currently under investigation as a new liver-targeted approach to managing type 2 diabetes mellitus (DM). The aim of the present study was to evaluate the inhibitory activity of a panel of 52 structurally related chromone derivatives; namely, flavonoids, 2-styrylchromones, 2-styrylchromone-related derivatives [2-(4-arylbuta-1,3-dien-1-yl)chromones], and 4- and 5-styrylpyrazoles against GP, using in silico and in vitro microanalysis screening systems. Several of the tested compounds showed a potent inhibitory effect. The structure–activity relationship study indicated that for 2-styrylchromones and 2-styrylchromone-related derivatives, the hydroxylations at the A and B rings, and in the flavonoid family, as well as the hydroxylation of the A ring, were determinants for the inhibitory activity. To support the in vitro experimental findings, molecular docking studies were performed, revealing clear hydrogen bonding patterns that favored the inhibitory effects of flavonoids, 2-styrylchromones, and 2-styrylchromone-related derivatives. Interestingly, the potency of the most active compounds increased almost four-fold when the concentration of glucose increased, presenting an IC50 < 10 µM. This effect may reduce the risk of hypoglycemia, a commonly reported side effect of antidiabetic agents. This work contributes with important considerations and provides a better understanding of potential scaffolds for the study of novel GP inhibitors.
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Affiliation(s)
- Sónia Rocha
- LAQV-REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (S.R.); (E.F.)
| | - Natália Aniceto
- Research Institute for Medicines, Faculdade de Farmácia, Universidade de Lisboa, 1649-003 Lisboa, Portugal; (N.A.); (R.C.G.); (M.L.C.)
| | - Rita C. Guedes
- Research Institute for Medicines, Faculdade de Farmácia, Universidade de Lisboa, 1649-003 Lisboa, Portugal; (N.A.); (R.C.G.); (M.L.C.)
| | - Hélio M. T. Albuquerque
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (H.M.T.A.); (V.L.M.S.); (A.M.S.S.)
| | - Vera L. M. Silva
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (H.M.T.A.); (V.L.M.S.); (A.M.S.S.)
| | - Artur M. S. Silva
- LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (H.M.T.A.); (V.L.M.S.); (A.M.S.S.)
| | - Maria Luísa Corvo
- Research Institute for Medicines, Faculdade de Farmácia, Universidade de Lisboa, 1649-003 Lisboa, Portugal; (N.A.); (R.C.G.); (M.L.C.)
| | - Eduarda Fernandes
- LAQV-REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (S.R.); (E.F.)
| | - Marisa Freitas
- LAQV-REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4050-313 Porto, Portugal; (S.R.); (E.F.)
- Correspondence: ; Tel.: +351-220-428-664
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Optimization and Validation of an In Vitro Standardized Glycogen Phosphorylase Activity Assay. Molecules 2021; 26:molecules26154635. [PMID: 34361792 PMCID: PMC8347172 DOI: 10.3390/molecules26154635] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 07/22/2021] [Accepted: 07/23/2021] [Indexed: 12/25/2022] Open
Abstract
Glycogen phosphorylase (GP) is a key enzyme in the glycogenolysis pathway and a potential therapeutic target in the management of type 2 diabetes. It catalyzes a reversible reaction: the release of the terminal glucosyl residue from glycogen as glucose 1-phosphate; or the transfer of glucose from glucose 1-phosphate to glycogen. A colorimetric method to follow in vitro the activity of GP with usefulness in structure-activity relationship studies and high-throughput screening capability is herein described. The obtained results allowed the choice of the optimal concentration of enzyme of 0.38 U/mL, 0.25 mM glucose 1-phosphate, 0.25 mg/mL glycogen, and temperature of 37 °C. Three known GP inhibitors, CP-91149, a synthetic inhibitor, caffeine, an alkaloid, and ellagic acid, a polyphenol, were used to validate the method, CP-91149 being the most active inhibitor. The effect of glucose on the IC50 value of CP-91149 was also investigated, which decreased when the concentration of glucose increased. The assay parameters for a high-throughput screening method for discovery of new potential GP inhibitors were optimized and standardized, which is desirable for the reproducibility and comparison of results in the literature. The optimized method can be applied to the study of a panel of synthetic and/or natural compounds, such as polyphenols.
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Dietary Anti-Aging Polyphenols and Potential Mechanisms. Antioxidants (Basel) 2021; 10:antiox10020283. [PMID: 33668479 PMCID: PMC7918214 DOI: 10.3390/antiox10020283] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 12/15/2022] Open
Abstract
For years, the consumption of a diet rich in fruits and vegetables has been considered healthy, increasing longevity, and decreasing morbidities. With the assistance of basic research investigating the potential mechanisms, it has become clear that the beneficial effects of plant-based foods are mainly due to the large amount of bioactive phenolic compounds contained. Indeed, substantial dietary intervention studies in humans have supported that the supplementation of polyphenols have various health-promoting effects, especially in the elderly population. In vitro examinations on the anti-aging mechanisms of polyphenols have been widely performed, using different types of natural and synthetic phenolic compounds. The aim of this review is to critically evaluate the experimental evidence demonstrating the beneficial effects of polyphenols on aging-related diseases. We highlight the potential anti-aging mechanisms of polyphenols, including antioxidant signaling, preventing cellular senescence, targeting microRNA, influencing NO bioavailability, and promoting mitochondrial function. While the trends on utilizing polyphenols in preventing aging-related disorders are getting growing attention, we suggest the exploration of the beneficial effects of the combination of multiple polyphenols or polyphenol-rich foods, as this would be more physiologically relevant to daily life.
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Brás NF, Neves RPP, Lopes FAA, Correia MAS, Palma AS, Sousa SF, Ramos MJ. Combined in silico and in vitro studies to identify novel antidiabetic flavonoids targeting glycogen phosphorylase. Bioorg Chem 2020; 108:104552. [PMID: 33357981 DOI: 10.1016/j.bioorg.2020.104552] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/13/2020] [Accepted: 12/09/2020] [Indexed: 02/02/2023]
Abstract
Novel pharmacological strategies for the treatment of diabetic patients are now focusing on inhibiting glycogenolysis steps. In this regard, glycogen phosphorylase (GP) is a validated target for the discovery of innovative antihyperglycemic molecules. Natural products, and in particular flavonoids, have been reported as potent inhibitors of GP at the cellular level. Herein, free-energy calculations and microscale thermophoresis approaches were performed to get an in-depth assessment of the binding affinities and elucidate intermolecular interactions of several flavonoids at the inhibitor site of GP. To our knowledge, this is the first study indicating genistein, 8-prenylgenistein, apigenin, 8-prenylapigenin, 8-prenylnaringenin, galangin and valoneic acid dilactone as natural molecules with high inhibitory potency toward GP. We identified: i) the residues Phe285, Tyr613, Glu382 and/or Arg770 as the most relevant for the binding of the best flavonoids to the inhibitor site of GP, and ii) the 5-OH, 7-OH, 8-prenyl substitutions in ring A and the 4'-OH insertion in ring B to favor flavonoid binding at this site. Our results are invaluable to plan further structural modifications through organic synthesis approaches and develop more effective pharmaceuticals for Type 2 Diabetes treatment, and serve as the starting point for the exploration of food products for therapeutic usage, as well as for the development of novel bio-functional food and dietary supplements/herbal medicines.
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Affiliation(s)
- Natércia F Brás
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
| | - Rui P P Neves
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal.
| | - Filipa A A Lopes
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia-Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Márcia A S Correia
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia-Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Angelina S Palma
- UCIBIO-REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia-Universidade NOVA de Lisboa, 2829-516 Caparica, Portugal
| | - Sérgio F Sousa
- UCIBIO-REQUIMTE, BioSIM, Departamento de Biomedicina, Faculdade de Medicina da Universidade do Porto, Alameda Professor Hernâni Monteiro, 4200-319 Porto, Portugal
| | - Maria J Ramos
- LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências Universidade do Porto, Rua do Campo Alegre s/n, 4169-007 Porto, Portugal
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Drakou CE, Gardeli C, Tsialtas I, Alexopoulos S, Mallouchos A, Koulas SM, Tsagkarakou AS, Asimakopoulos D, Leonidas DD, Psarra AMG, Skamnaki VT. Affinity Crystallography Reveals Binding of Pomegranate Juice Anthocyanins at the Inhibitor Site of Glycogen Phosphorylase: The Contribution of a Sugar Moiety to Potency and Its Implications to the Binding Mode. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2020; 68:10191-10199. [PMID: 32840370 DOI: 10.1021/acs.jafc.0c04205] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Anthocyanins (ACNs) are dietary phytochemicals with an acknowledged therapeutic significance. Pomegranate juice (PJ) is a rich source of ACNs with potential applications in nutraceutical development. Glycogen phosphorylase (GP) catalyzes the first step of glycogenolysis and is a molecular target for the development of antihyperglycemics. The inhibitory potential of the ACN fraction of PJ is assessed through a combination of in vitro assays, ex vivo investigation in hepatic cells, and X-ray crystallography studies. The ACN extract potently inhibits muscle and liver isoforms of GP. Affinity crystallography reveals the structural basis of inhibition through the binding of pelargonidin-3-O-glucoside at the GP inhibitor site. The glucopyranose moiety is revealed as a major determinant of potency as it promotes a structural binding mode different from that observed for other flavonoids. This inhibitory effect of the ACN scaffold and its binding mode at the GP inhibitor binding site may have significant implications for future structure-based drug design endeavors.
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Affiliation(s)
- Christina E Drakou
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Chrysavgi Gardeli
- Department of Food Science and Human Nutrition, Agricultural University of Athens, Athens 118 55, Greece
| | - Ioannis Tsialtas
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Serafeim Alexopoulos
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Athanasios Mallouchos
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Symeon M Koulas
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Anastasia S Tsagkarakou
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Demetres Asimakopoulos
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Demetres D Leonidas
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Anna-Maria G Psarra
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
| | - Vasiliki T Skamnaki
- Department of Biochemistry and Biotechnology, University of Thessaly, Biopolis 41500, Larisa, Greece
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Synthetic flavonoid derivatives targeting the glycogen phosphorylase inhibitor site: QM/MM-PBSA motivated synthesis of substituted 5,7-dihydroxyflavones, crystallography, in vitro kinetics and ex-vivo cellular experiments reveal novel potent inhibitors. Bioorg Chem 2020; 102:104003. [DOI: 10.1016/j.bioorg.2020.104003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 06/02/2020] [Accepted: 06/07/2020] [Indexed: 01/31/2023]
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Zhang L, Yan Z, Wang Y, Song C, Miao G. Design, Synthesis, and Biological Application of Novel Photoaffinity Probes of Dihydropyridine Derivatives, BAY R3401. Molecules 2019; 24:molecules24132394. [PMID: 31261804 PMCID: PMC6652023 DOI: 10.3390/molecules24132394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/23/2019] [Accepted: 06/28/2019] [Indexed: 11/16/2022] Open
Abstract
To explore the molecular mechanisms of BAY R3401, four types of novel photoaffinity probes bearing different secondary tags were synthesized. Their potency for glycogenolysis was evaluated in primary human liver HL-7702 cells and HepG2 cells. Probe 2d showed the best activity in primary human liver HL-7702 cells and HepG2 cells, with IC50 values of 4.45 μM and 28.49 μM, respectively. Likewise, probe 5d showed IC50 values of 6.46 μM in primary human liver HL-7702 cells and 15.29 μM in HepG2 cells, respectively. Photoaffinity labeling experiments were also performed and protein bands larger than 170 kDa were specifically tagged by probe 2d. The results suggest that the synthesized probe 2d might be a very promising tool for the isolation of the target proteins of BAY R3401.
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Affiliation(s)
- Liying Zhang
- Key Laboratory of Traditional Chinese Medicine Research and Development of Hebei Province, Institute of Traditional Chinese Medicine, Chengde Medical University, Chengde 067000, China.
| | - Zhiwei Yan
- Key Laboratory of Traditional Chinese Medicine Research and Development of Hebei Province, Institute of Traditional Chinese Medicine, Chengde Medical University, Chengde 067000, China
| | - Youde Wang
- Key Laboratory of Traditional Chinese Medicine Research and Development of Hebei Province, Institute of Traditional Chinese Medicine, Chengde Medical University, Chengde 067000, China
| | - Chengjun Song
- Department of Human Anatomy, Chengde Medical University, Chengde 067000, China
| | - Guangxin Miao
- Key Laboratory of Traditional Chinese Medicine Research and Development of Hebei Province, Institute of Traditional Chinese Medicine, Chengde Medical University, Chengde 067000, China
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Jasmin, Jaitak V. A Review on Molecular Mechanism of Flavonoids as Antidiabetic Agents. Mini Rev Med Chem 2019; 19:762-786. [DOI: 10.2174/1389557519666181227153428] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 12/17/2018] [Accepted: 12/18/2018] [Indexed: 02/06/2023]
Abstract
The development of drugs possessing anti-diabetic activities is a long pursued goal in drug
discovery. It has been shown that deregulated insulin mediated signaling, oxidative stress, obesity, and
β-cell dysfunction are the main factors responsible for the disease. With the advent of new and more
powerful screening assays and prediction tools, the idea of a drug that can effectively treat diabetes by
targeting different pathways has re-bloomed. Current anti-diabetic therapy is based on synthetic drugs
that very often have side effects. For this reason, there is an instantaneous need to develop or search
new alternatives. Recently, more attention is being paid to the study of natural products. Their huge
advantage is that they can be ingested in everyday diet. Here, we discuss various causes, putative targets,
and treatment strategies, mechanistic aspects as well as structural features with a particular focus
on naturally occurring flavonoids as promising starting points for anti-diabetic led development.
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Affiliation(s)
- Jasmin
- Laboratory of Natural Products, Department of Pharmaceutical Sciences and Natural Products, Central University of Punjab, Bathinda (Pb.) 151001, India
| | - Vikas Jaitak
- Laboratory of Natural Products, Department of Pharmaceutical Sciences and Natural Products, Central University of Punjab, Bathinda (Pb.) 151001, India
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15
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Szabó K, Kandra L, Gyémánt G. Studies on the reversible enzyme reaction of rabbit muscle glycogen phosphorylase b using isothermal titration calorimetry. Carbohydr Res 2019; 477:58-65. [PMID: 31005807 DOI: 10.1016/j.carres.2019.03.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/27/2019] [Accepted: 03/30/2019] [Indexed: 10/27/2022]
Abstract
Glycogen phosphorylase enzymes (GP) catalyse reversible reactions; the glucose transfer from glycogen to inorganic phosphate (Pi, phosphorolysis) or the reverse glucose transfer from glucose-1-phosphate (G-1-P) to glycogen (synthesis). Rabbit muscle GPb (rmGPb) was used as a model enzyme to study the reversible enzyme reaction. To follow both directions of this reversible reaction, we have developed a novel isothermal titration calorimetry (ITC) method for the determination of the direct reaction rate. The preference of forward or reverse reaction was ensured by the 0.1 or 10 concentration ratios of G-1-P/Pi, respectively. Substrate specificity was studied using different maltooligosaccharides and glycogen. Based on the KM values, glycogen and 2-chloro-4-nitrophenyl maltoheptaoside (CNP-G7) were found to be analogous substrates, which allowed to optimize the method by taking advantage of the CNP chromophore being detectable in HPLC. In case of CNP-G7, substrate inhibition was observed and characterised by Ki of 23 ± 7 mM. Inhibition of human GP is a promising strategy for the treatment of diabetes. Our ITC measurements have confirmed that caffeine and glucopyranosylidene-spiro-thiohydantoin (GTH), as known GPb inhibitors, inhibit the rmGPb-catalysed reversible reaction in both directions. Ki values obtained in the direction of synthesis (1.92 ± 0.14 mM for caffeine and 11.5 ± 2.0 μM for GTH) have been shown to be in good agreement with the Ki values obtained in the direction of phosphorolysis (4.05 ± 0.26 mM for caffeine and 13.8 ± 1.6 μM for GTH). The higher difference between the inhibition constants of caffeine was explained by the non-competitive mechanism. The described ITC method using the developed experimental design and reaction conditions is suitable for activity measurements of different phosphorylase enzymes on various substrates and is applicable for inhibition studies as well.
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Affiliation(s)
- Kármen Szabó
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Lili Kandra
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary
| | - Gyöngyi Gyémánt
- Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary.
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16
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Xiao J. Dietary flavonoid aglycones and their glycosides: Which show better biological significance? Crit Rev Food Sci Nutr 2017; 57:1874-1905. [PMID: 26176651 DOI: 10.1080/10408398.2015.1032400] [Citation(s) in RCA: 178] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The dietary flavonoids, especially their glycosides, are the most vital phytochemicals in diets and are of great general interest due to their diverse bioactivity. The natural flavonoids almost all exist as their O-glycoside or C-glycoside forms in plants. In this review, we summarized the existing knowledge on the different biological benefits and pharmacokinetic behaviors between flavonoid aglycones and their glycosides. Due to various conclusions from different flavonoid types and health/disease conditions, it is very difficult to draw general or universally applicable comments regarding the impact of glycosylation on the biological benefits of flavonoids. It seems as though O-glycosylation generally reduces the bioactivity of these compounds - this has been observed for diverse properties including antioxidant activity, antidiabetes activity, anti-inflammation activity, antibacterial, antifungal activity, antitumor activity, anticoagulant activity, antiplatelet activity, antidegranulating activity, antitrypanosomal activity, influenza virus neuraminidase inhibition, aldehyde oxidase inhibition, immunomodulatory, and antitubercular activity. However, O-glycosylation can enhance certain types of biological benefits including anti-HIV activity, tyrosinase inhibition, antirotavirus activity, antistress activity, antiobesity activity, anticholinesterase potential, antiadipogenic activity, and antiallergic activity. However, there is a lack of data for most flavonoids, and their structures vary widely. There is also a profound lack of data on the impact of C-glycosylation on flavonoid biological benefits, although it has been demonstrated that in at least some cases C-glycosylation has positive effects on properties that may be useful in human healthcare such as antioxidant and antidiabetes activity. Furthermore, there is a lack of in vivo data that would make it possible to make broad generalizations concerning the influence of glycosylation on the benefits of flavonoids for human health. It is possible that the effects of glycosylation on flavonoid bioactivity in vitro may differ from that seen in vivo. With in vivo (oral) treatment, flavonoid glycosides showed similar or even higher antidiabetes, anti-inflammatory, antidegranulating, antistress, and antiallergic activity than their flavonoid aglycones. Flavonoid glycosides keep higher plasma levels and have a longer mean residence time than those of aglycones. We should pay more attention to in vivo benefits of flavonoid glycosides, especially C-glycosides.
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Affiliation(s)
- Jianbo Xiao
- a Institute of Chinese Medical Sciences, State Key Laboratory of Quality Research in Chinese Medicine, University of Macau , Taipa , Macau.,b Institut für Pharmazie und Lebensmittelchemie, Universität Würzburg , Am Hubland , Würzburg , Germany
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17
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Sordon S, Madej A, Popłoński J, Bartmańska A, Tronina T, Brzezowska E, Juszczyk P, Huszcza E. Regioselective ortho-Hydroxylations of Flavonoids by Yeast. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2016; 64:5525-5530. [PMID: 27324975 DOI: 10.1021/acs.jafc.6b02210] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Natural flavonoids, such as naringenin, hesperetin, chrysin, apigenin, luteolin, quercetin, epicatechin, and biochanin A, were subjected to microbiological transformations by Rhodotorula glutinis. Yeast was able to regioselectively C-8 hydroxylate hesperetin, luteolin, and chrysin. Naringenin was transformed to 8- and 6-hydroxyderivatives. Quercetin, epicatechin, and biochanin A did not undergo biotransformation. A metabolic pathway for the degradation of chrysin has been elucidated. The metabolism of chrysin proceeds via an initial C-8 hydroxylation to norwogonin, followed by A-ring cleavage to 4-hydroxy-6-phenyl-2H-pyran-2-one.
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Affiliation(s)
- Sandra Sordon
- Department of Chemistry, Wrocław University of Environmental and Life Sciences , Norwida 25, 50-375 Wroclaw, Poland
| | - Anna Madej
- Department of Chemistry, Wrocław University of Environmental and Life Sciences , Norwida 25, 50-375 Wroclaw, Poland
| | - Jarosław Popłoński
- Department of Chemistry, Wrocław University of Environmental and Life Sciences , Norwida 25, 50-375 Wroclaw, Poland
| | - Agnieszka Bartmańska
- Department of Chemistry, Wrocław University of Environmental and Life Sciences , Norwida 25, 50-375 Wroclaw, Poland
| | - Tomasz Tronina
- Department of Chemistry, Wrocław University of Environmental and Life Sciences , Norwida 25, 50-375 Wroclaw, Poland
| | - Ewa Brzezowska
- Department of Chemistry, Wrocław University of Environmental and Life Sciences , Norwida 25, 50-375 Wroclaw, Poland
| | - Piotr Juszczyk
- Department of Biotechnology and Food Microbiology, Wrocław University of Environmental and Life Sciences , Chełmońskiego 37/41, 51-630 Wrocław, Poland
| | - Ewa Huszcza
- Department of Chemistry, Wrocław University of Environmental and Life Sciences , Norwida 25, 50-375 Wroclaw, Poland
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Kyriakis E, Stravodimos GA, Kantsadi AL, Chatzileontiadou DS, Skamnaki VT, Leonidas DD. Natural flavonoids as antidiabetic agents. The binding of gallic and ellagic acids to glycogen phosphorylase b. FEBS Lett 2015; 589:1787-94. [DOI: 10.1016/j.febslet.2015.05.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 04/28/2015] [Accepted: 05/01/2015] [Indexed: 12/17/2022]
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19
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Natural Flavonoids as Potential Herbal Medication for the Treatment of Diabetes Mellitus and its Complications. Nat Prod Commun 2015. [DOI: 10.1177/1934578x1501000140] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Diabetes mellitus, together with its various complications, is becoming a serious threat to human health. Natural products are secondary metabolites widely distributed in plants, having a broad range of biological activities. The development of antidiabetic medication from natural products, especially those originating from plants with a traceable folk-usage history in treating diabetes, is receiving more attention. Many studies highlighted not only the benefits of natural flavonoids with hypoglycemic effects, but also their importance in the management of diabetic complications. This review describes selected natural flavonoids that have been validated for their hypoglycemic properties, together with their mechanisms of action. Also discussed are their activities in the treatment of diabetic complications demonstrated via laboratory diabetic animal models, in vitro and clinical trials using human subjects. Published papers from 2000 to date on flavonoids and diabetes were covered through accessing Web of Science and multiple databases for biomedical sciences. The major potential benefits of natural flavonoids discussed in this review clearly suggest that these substances are lead compounds with sufficient structural diversity of great importance in the antidiabetic drug developing process.
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20
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A novel copigment of quercetagetin for stabilization of grape skin anthocyanins. Food Chem 2015; 166:50-55. [DOI: 10.1016/j.foodchem.2014.05.125] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 05/22/2014] [Accepted: 05/23/2014] [Indexed: 11/24/2022]
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21
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Xiao J, Muzashvili TS, Georgiev MI. Advances in the biotechnological glycosylation of valuable flavonoids. Biotechnol Adv 2014; 32:1145-56. [PMID: 24780153 DOI: 10.1016/j.biotechadv.2014.04.006] [Citation(s) in RCA: 211] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 04/16/2014] [Accepted: 04/17/2014] [Indexed: 02/08/2023]
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22
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Sanae F, Kamiyama O, Ikeda-Obatake K, Higashi Y, Asano N, Adachi I, Kato A. Effects of eugenol-reduced clove extract on glycogen phosphorylase b and the development of diabetes in db/db mice. Food Funct 2014; 5:214-9. [PMID: 24336787 DOI: 10.1039/c3fo60514k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We found that the 50% aqueous EtOH extract of clove (Syzygium aromaticum) had potent dose-dependent inhibitory activity toward glycogen phosphorylase b and glucagon-stimulated glucose production in primary rat hepatocytes. Among the components, eugeniin inhibited glycogen phosphorylase b and glucagon-stimulated glucose production in primary rat hepatocytes, with IC50 values of 0.14 and 4.7 μM, respectively. In sharp contrast, eugenol showed no significant inhibition toward glycogen phosphorylase b, even at a concentration of 400 μM. Eugenol-reduced clove extracts (erCE) were prepared and when fed to a db/db mouse they clearly suppressed the blood glucose and HbA1c levels. Furthermore, plasma triglyceride and non-esterified fatty acid levels in 5% and 10% erCE-fed db/db mice were significantly lowered, compared with control db/db mice without erCE supplementation. These results suggested that dietary supplementation with the erCE could beneficially modify glucose and lipid metabolism and contribute to the prevention of the progress of hyperglycemia and metabolic syndrome.
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Affiliation(s)
- Fujiko Sanae
- Faculty of Pharmaceutical Sciences, Hokuriku University, Kanazawa 920-1181, Japan
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23
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Prasath GS, Pillai SI, Subramanian SP. Fisetin improves glucose homeostasis through the inhibition of gluconeogenic enzymes in hepatic tissues of streptozotocin induced diabetic rats. Eur J Pharmacol 2014; 740:248-54. [PMID: 25064342 DOI: 10.1016/j.ejphar.2014.06.065] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 06/13/2014] [Accepted: 06/17/2014] [Indexed: 11/26/2022]
Abstract
Liver plays a vital role in blood glucose homeostasis. Recent studies have provided considerable evidence that hepatic glucose production (HGP) plays an important role in the development of fasting hyperglycemia in diabetes. From this perspective, diminution of HGP has certainly been considered for the treatment of diabetes. In the present study, we have analyzed the modulatory effects of fisetin, a flavonoid of strawberries, on the expression of key enzymes of carbohydrate metabolism in STZ induced experimental diabetic rats. The physiological criterions such as food and fluid intake were regularly monitored. The levels of blood glucose, plasma insulin, hemoglobin and glycosylated hemoglobin were analyzed. The mRNA and protein expression levels of gluconeogenic genes such as phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) were determined by immunoblot as well as PCR analysis. Diabetic group of rats showed significant increase in food and water intake when compared with control group of rats. Upon oral administration of fisetin as well as gliclazide to diabetic group of rats, the levels were found to be decreased. Oral administration of fisetin (10 mg/kg body weight) to diabetic rats for 30 days established a significant decline in blood glucose and glycosylated hemoglobin levels and a significant increase in plasma insulin level. The mRNA and protein expression levels of gluconeogenic genes, such as phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase), were decreased in liver tissues upon treatment with fisetin. The results of the present study suggest that fisetin improves glucose homeostasis by direct inhibition of gluconeogenesis in liver.
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Affiliation(s)
- Gopalan Sriram Prasath
- Department of Biochemistry, University of Madras, Guindy Campus, Chennai 600025, Tamil Nadu, India
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24
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Xiao J, Chen T, Cao H. WITHDRAWN: Flavonoid glycosylation and biological benefits. Biotechnol Adv 2014:S0734-9750(14)00092-5. [PMID: 24858477 DOI: 10.1016/j.biotechadv.2014.05.004] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2014] [Revised: 05/09/2014] [Accepted: 05/11/2014] [Indexed: 01/16/2023]
Abstract
This article has been withdrawn at the request of the editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
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Affiliation(s)
- Jianbo Xiao
- Department of Biology, Shanghai Normal University, 100 Guilin Rd, Shanghai 200234, China; Institut für Pharmazie und Lebensmittelchemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany; Anhui Academy of Applied Technology, Suixi Road 312, 230031 Hefei, Anhui, China.
| | - Tingting Chen
- School of Chemistry and Chemical Engineering, Nantong University, Nantong 226007, China
| | - Hui Cao
- Institut für Pharmazie und Lebensmittelchemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany; School of Chemistry and Chemical Engineering, Nantong University, Nantong 226007, China.
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25
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Da Silva D, Casanova LM, Marcondes MC, Espindola-Netto JM, Paixão LP, De Melo GO, Zancan P, Sola-Penna M, Costa SS. Antidiabetic activity ofSedum dendroideum: Metabolic enzymes as putative targets for the bioactive flavonoid kaempferitrin. IUBMB Life 2014; 66:361-70. [DOI: 10.1002/iub.1270] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Accepted: 04/23/2014] [Indexed: 01/08/2023]
Affiliation(s)
- Daniel Da Silva
- Laboratório de Enzimologia e Controle do Metabolismo (LabECoM), BioTecFar, Faculdade de Farmácia; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Livia Marques Casanova
- Laboratório de Química de Produtos Naturais Bioativos (LPN-Bio), Núcleo de Pesquisa de Produtos Naturais; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Mariah Celestino Marcondes
- Laboratório de Oncobiologia Molecular (LabOMol), BioTecFar, Faculdade de Farmácia; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Jair Machado Espindola-Netto
- Laboratório de Enzimologia e Controle do Metabolismo (LabECoM), BioTecFar, Faculdade de Farmácia; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Larissa Pereira Paixão
- Laboratório de Oncobiologia Molecular (LabOMol), BioTecFar, Faculdade de Farmácia; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Giany Oliveira De Melo
- Laboratório de Química de Produtos Naturais Bioativos (LPN-Bio), Núcleo de Pesquisa de Produtos Naturais; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Patricia Zancan
- Laboratório de Oncobiologia Molecular (LabOMol), BioTecFar, Faculdade de Farmácia; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Mauro Sola-Penna
- Laboratório de Enzimologia e Controle do Metabolismo (LabECoM), BioTecFar, Faculdade de Farmácia; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
| | - Sônia Soares Costa
- Laboratório de Química de Produtos Naturais Bioativos (LPN-Bio), Núcleo de Pesquisa de Produtos Naturais; Universidade Federal do Rio de Janeiro; Rio de Janeiro Brazil
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Biochemical and biological assessment of the inhibitory potency of extracts from vinification byproducts of Vitis vinifera extracts against glycogen phosphorylase. Food Chem Toxicol 2014; 67:35-43. [DOI: 10.1016/j.fct.2014.01.055] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 01/23/2014] [Accepted: 01/31/2014] [Indexed: 01/22/2023]
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27
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Gaboriaud-Kolar N, Skaltsounis AL. Glycogen phosphorylase inhibitors: a patent review (2008 - 2012). Expert Opin Ther Pat 2013; 23:1017-32. [PMID: 23627914 DOI: 10.1517/13543776.2013.794790] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
INTRODUCTION Glycogen phosphorylase (GP) is the enzyme responsible for the synthesis of glucose-1-phosphate, the source of energy for muscles and the rest of the body. The binding of different ligands in catalytic or allosteric sites assures activation and deactivation of the enzyme. A description of the regulation mechanism and the implications in glycogen metabolism are given. AREAS COVERED Deregulation of GP has been observed in diseases such as diabetes mellitus or cancers. Therefore, it appears as an attractive therapeutic target for the treatment of such pathologies. Numbers of inhibitors have been published in academic literature or patented in the last two decades. This review presents the main patent claims published between 2008 and 2012. EXPERT OPINION Good inhibitors with interesting IC50 and in vivo results are presented. However, such therapeutic strategy raises questions and some answers are proposed to bring new insights in the field.
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Krych J, Gebicka L. Catalase is inhibited by flavonoids. Int J Biol Macromol 2013; 58:148-53. [PMID: 23567286 DOI: 10.1016/j.ijbiomac.2013.03.070] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 03/27/2013] [Accepted: 03/29/2013] [Indexed: 01/01/2023]
Abstract
Catalases, heme enzymes, which catalyze decomposition of hydrogen peroxide to water and molecular oxygen, belong to the antioxidant defense system of the cell. In this work we have shown that catalase from bovine liver is inhibited by flavonoids. The inhibition is, at least partially, due to the formation of hydrogen bonds between catalase and flavonoids. In the presence of some flavonoids the formation of unreactive catalase compound II has been detected. The most potent catalase inhibitors among the tested flavonoids have appeared myricetin, epicatechin gallate and epigallocatechin gallate. The relationship between the degree of enzyme inhibition and molecular structure of flavonoids has been analyzed.
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Affiliation(s)
- Justyna Krych
- Institute of Applied Radiation Chemistry, Faculty of Chemistry, Lodz University of Technology (TUL), Lodz, Poland
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29
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Sourcing the affinity of flavonoids for the glycogen phosphorylase inhibitor site via crystallography, kinetics and QM/MM-PBSA binding studies: comparison of chrysin and flavopiridol. Food Chem Toxicol 2012; 61:14-27. [PMID: 23279842 DOI: 10.1016/j.fct.2012.12.030] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Revised: 12/18/2012] [Accepted: 12/20/2012] [Indexed: 11/21/2022]
Abstract
Flavonoids have been discovered as novel inhibitors of glycogen phosphorylase (GP), a target to control hyperglycemia in type 2 diabetes. To elucidate the mechanism of inhibition, we have determined the crystal structure of the GPb-chrysin complex at 1.9 Å resolution. Chrysin is accommodated at the inhibitor site intercalating between the aromatic side chains of Phe285 and Tyr613 through π-stacking interactions. Chrysin binds to GPb approximately 15 times weaker (Ki=19.01 μM) than flavopiridol (Ki=1.24 μM), exclusively at the inhibitor site, and both inhibitors display similar behavior with respect to AMP. To identify the source of flavopiridols' stronger affinity, molecular docking with Glide and postdocking binding free energy calculations using QM/MM-PBSA have been performed and compared. Whereas docking failed to correctly rank inhibitor binding conformations, the QM/MM-PBSA method employing M06-2X/6-31+G to model the π-stacking interactions correctly reproduced the experimental results. Flavopiridols' greater binding affinity is sourced to favorable interactions of the cationic 4-hydroxypiperidin-1-yl substituent with GPb, with desolvation effects limited by the substituent conformation adopted in the crystallographic complex. Further successful predictions using QM/MM-PBSA for the flavonoid quercetagetin (which binds at the allosteric site) leads us to propose the methodology as a useful and inexpensive tool to predict flavonoid binding.
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30
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Chang LS, Li CB, Qin N, Jin MN, Duan HQ. Synthesis and antidiabetic activity of 5,7-dihydroxyflavonoids and analogs. Chem Biodivers 2012; 9:162-9. [PMID: 22253113 DOI: 10.1002/cbdv.201100049] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
In a study to evaluate the structural elements essential for the antidiabetic activity of flavonoids, we synthesized two series of flavonoids, 5,7-dihydroxyflavanones and 5,7-dihydroxyflavones. In a screening for potential antidiabetic activity, most of the flavonoids showed a remarkable in vitro activity, and compounds 1f, 2d, and 3c were significantly more effective than the positive control, metformin. The biological activity was mainly affected by structural modification at the ring B moiety of the flavonoid skeleton. The results suggest that 5,7-dihydroxyflavonoids can be considered as promising candidates in the development of new antidiabetic lead compounds.
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Affiliation(s)
- Liu-Shuan Chang
- School of Pharmaceutical Sciences, Research Center of Basic Medical Sciences, Tianjin Medical University, Tianjin 300070, P. R. China
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Khan HBH, Vinayagam KS, Sekar A, Palanivelu S, Panchanadham S. Antidiabetic and antioxidant effect of Semecarpus anacardium Linn. nut milk extract in a high-fat diet STZ-induced type 2 diabetic rat model. J Diet Suppl 2012; 9:19-33. [PMID: 22432800 DOI: 10.3109/19390211.2011.631099] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Semecarpus anacardium commonly known as marking nut has been used in the Siddha system of medicine against various ailments. The antidiabetic and antioxidant potential of the drug was evaluated in Type 2 diabetic rats induced by feeding a high-fat diet (HFD) for 2 weeks followed by single intraperitoneal injection of streptozotocin (STZ) 35 mg/kg body weight. Three days after STZ induction, the hyperglycemic rats were treated with Semecarpus anacardium nut milk extract (SA) orally at a dosage of 200 mg/kg body weight daily for 30 days. Metformin (500 mg/kg body weight, orally) was used as a reference drug. The fasting blood glucose, insulin, Hb, HbA1c levels, and HOMA-IR and HOMA-β were measured, and also the levels of lipid peroxidation and antioxidant enzymes were observed. SA significantly (p < .05) reduced and normalized blood glucose levels and also decreased the levels of HbA1c as compared with that of HFD STZ control group. SA treatment also significantly (p < .05) increased the levels of antioxidant enzymes while decreasing the levels of lipid peroxidation. The potential antihyperglycemic action and antioxidant role might be due to the presence of flavonoids in the drug.
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Colturato CP, Constantin RP, Maeda AS, Constantin RP, Yamamoto NS, Bracht A, Ishii-Iwamoto EL, Constantin J. Metabolic effects of silibinin in the rat liver. Chem Biol Interact 2012; 195:119-32. [DOI: 10.1016/j.cbi.2011.11.006] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Revised: 11/11/2011] [Accepted: 11/15/2011] [Indexed: 10/15/2022]
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Xiao J, Kai G. A Review of Dietary Polyphenol-Plasma Protein Interactions: Characterization, Influence on the Bioactivity, and Structure-Affinity Relationship. Crit Rev Food Sci Nutr 2012; 52:85-101. [PMID: 21991992 DOI: 10.1080/10408398.2010.499017] [Citation(s) in RCA: 164] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Qin N, Li CB, Jin MN, Shi LH, Duan HQ, Niu WY. Synthesis and biological activity of novel tiliroside derivants. Eur J Med Chem 2011; 46:5189-95. [DOI: 10.1016/j.ejmech.2011.07.059] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 07/18/2011] [Accepted: 07/31/2011] [Indexed: 02/05/2023]
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Wilson T, Luebke JL, Morcomb EF, Carrell EJ, Leveranz MC, Kobs L, Schmidt TP, Limburg PJ, Vorsa N, Singh AP. Glycemic responses to sweetened dried and raw cranberries in humans with type 2 diabetes. J Food Sci 2011; 75:H218-23. [PMID: 21535498 DOI: 10.1111/j.1750-3841.2010.01800.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
This study assessed the metabolic response to sweetened dried cranberries (SDC), raw cranberries (RC), and white bread (WB) in humans with type 2 diabetes. Development of palatable cranberry preparations associated with lower glycemic responses may be useful for improving fruit consumption and glycemic control among those with diabetes. In this trial, type 2 diabetics (n= 13) received WB (57 g, 160 cal, 1 g fiber), RC (55 g, 21 cal, 1 g fiber), SDC (40 g, 138 cal, 2.1 g fiber), and SDC containing less sugar (SDC-LS, 40 g, 113 cal, 1.8 g fiber + 10 g polydextrose). Plasma glucose (mmol/L) peaked significantly at 60 min for WB, and at 30 min for RC, SDC, and SDC-LS at 9.6 ± 0.4, 7.0 ± 0.4, 9.6 ± 0.5, and 8.7 ± 0.5, respectively, WB remained significantly elevated from the other treatments at 120 min. Plasma insulin (pmol/mL) peaked at 60 min for WB and SDC and at 30 min for RC and SDC-LS at 157 ± 15, 142 ± 27, 61 ± 8, and 97 ± 11, respectively. Plasma insulin for SDC-LS was significantly lower at 60 min than either WB or SDC. Insulin area under the curve (AUC) values for RC and SDC-LS were both significantly lower than WB or SDC. Phenolic content of SDC and SDC-LS was determined following extraction with 80% acetone prior to high-performance liquid chromatography (HPLC) and electronspray ionization-mass spectrometry (ESI-MS) and found to be rich in 5-caffeoylquinic cid, quercetin-3-galactoside, and quercetin-3-galactoside, and the proanthocyanidin dimer epicatechin. In conclusion, SDC-LS was associated with a favorable glycemic and insulinemic response in type 2 diabetics. Practical Application: This study compares phenolic content and glycemic responses among different cranberry products. The study seeks to expand the palatable and portable healthy food choices for persons with type 2 diabetes. The novel use of polydextrose as a bulking agent making possible a reduction in caloric content and potential glycemic response is also characterized in this study.
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Affiliation(s)
- Ted Wilson
- Dept. of Biology, Winona State Univ., Winona, MN, USA.
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Synthesis and biological activity of trans-tiliroside derivatives as potent anti-diabetic agents. Molecules 2010; 15:9174-83. [PMID: 21150832 PMCID: PMC6259203 DOI: 10.3390/molecules15129174] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2010] [Revised: 12/07/2010] [Accepted: 12/08/2010] [Indexed: 11/16/2022] Open
Abstract
A set of novel trans-tiliroside derivatives were synthesized. The structures of the derivatives were identified by their IR, 1H-NMR, and MS spectra analysis. Their anti-diabetic activities were evaluated on the insulin resistant (IR) HepG2 cell model. As a result, compounds 7a, 7c, 7h, and trans-tiliroside exhibited significant glucose consumption-enhancing effects in IR-HepG2 cells compared with the positive control (metformin). This research provides useful clues for further design and discovery of anti-diabetic agents.
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Constantin RP, Constantin J, Pagadigorria CLS, Ishii-Iwamoto EL, Bracht A, de Castro CV, Yamamoto NS. Prooxidant activity of fisetin: effects on energy metabolism in the rat liver. J Biochem Mol Toxicol 2010; 25:117-26. [PMID: 20957679 DOI: 10.1002/jbt.20367] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 06/18/2010] [Accepted: 07/07/2010] [Indexed: 11/08/2022]
Abstract
Flavonols, which possess the B-catechol ring, as quercetin, are capable of producing o-hemiquinones and to oxidize NADH in a variety of mammalian cells. The purpose of this study was to investigate whether fisetin affects the liver energy metabolism and the mitochondrial NADH to NAD+ ratio. The action of fisetin on hepatic energy metabolism was investigated in the perfused rat liver and isolated mitochondria. In isolated mitochondria, fisetin decreased the respiratory control and ADP/O ratios with the substrates α-ketoglutarate and succinate. In the presence of ADP, respiration of isolated mitochondria was inhibited with both substrates, indicating an inhibitory action on the ATP-synthase. The stimulation of the ATPase activity of coupled mitochondria and the inhibition of NADH-oxidase activity pointed toward a possible uncoupling action and the interference of fisetin with mitochondrial energy transduction mechanisms. In livers from fasted rats, fisetin inhibited ketogenesis from endogenous sources. The β-hydroxybutyrate/ acetoacetate ratio, which reflects the mitochondrial NADH/NAD+ redox ratio, was also decreased. In addition, fisetin (200 μM) increased the production of (14)CO2 from exogenous oleate. The results of this investigation suggest that fisetin causes a shift in the mitochondrial redox potential toward a more oxidized state with a clear predominance of its prooxidant activity.
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Choi KC, Chung WT, Kwon JK, Yu JY, Jang YS, Park SM, Lee SY, Lee JC. Inhibitory effects of quercetin on aflatoxin B1-induced hepatic damage in mice. Food Chem Toxicol 2010; 48:2747-53. [DOI: 10.1016/j.fct.2010.07.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 07/04/2010] [Accepted: 07/05/2010] [Indexed: 10/19/2022]
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Kato A, Kobayashi K, Narukawa K, Minoshima Y, Adachi I, Hirono S, Nash RJ. 6,7-Dihydroxy-4-phenylcoumarin as inhibitor of aldose reductase 2. Bioorg Med Chem Lett 2010; 20:5630-3. [DOI: 10.1016/j.bmcl.2010.08.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Revised: 08/06/2010] [Accepted: 08/09/2010] [Indexed: 11/17/2022]
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Kamiyama O, Sanae F, Ikeda K, Higashi Y, Minami Y, Asano N, Adachi I, Kato A. In vitro inhibition of α-glucosidases and glycogen phosphorylase by catechin gallates in green tea. Food Chem 2010. [DOI: 10.1016/j.foodchem.2010.03.075] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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41
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Torres-Piedra M, Ortiz-Andrade R, Villalobos-Molina R, Singh N, Medina-Franco JL, Webster SP, Binnie M, Navarrete-Vázquez G, Estrada-Soto S. A comparative study of flavonoid analogues on streptozotocin–nicotinamide induced diabetic rats: Quercetin as a potential antidiabetic agent acting via 11β-Hydroxysteroid dehydrogenase type 1 inhibition. Eur J Med Chem 2010; 45:2606-12. [DOI: 10.1016/j.ejmech.2010.02.049] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Revised: 12/21/2009] [Accepted: 02/19/2010] [Indexed: 10/19/2022]
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42
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Constantin RP, Constantin J, Pagadigorria CLS, Ishii-Iwamoto EL, Bracht A, Ono MDKC, Yamamoto NS. The actions of fisetin on glucose metabolism in the rat liver. Cell Biochem Funct 2010; 28:149-58. [PMID: 20084677 DOI: 10.1002/cbf.1635] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Fisetin is a flavonoid dietary ingredient found in the smoke tree (Cotinus coggyria) and in several fruits and vegetables. The effects of fisetin on glucose metabolism in the isolated perfused rat liver and some glucose-regulating enzymatic activities were investigated. Fisetin inhibited glucose, lactate, and pyruvate release from endogenous glycogen. Maximal inhibitions of glycogenolysis (49%) and glycolysis (59%) were obtained with the concentration of 200 microM. The glycogenolytic effects of glucagon and dinitrophenol were suppressed by fisetin 300 microM. No significant changes in the cellular contents of AMP, ADP, and ATP were found. Fisetin increased the cellular content of glucose 6-phosphate and inhibited the glucose 6-phosphatase activity. Gluconeogenesis from lactate and pyruvate or fructose was inhibited by fisetin 300 microM. Pyruvate carboxylation in isolated intact mitochondria was inhibited (IC(50) = 163.10 +/- 12.28 microM); no such effect was observed in freeze-thawing disrupted mitochondria. It was concluded that fisetin inhibits glucose release from the livers in both fed and fasted conditions. The inhibition of pyruvate transport into the mitochondria and the reduction of the cytosolic NADH-NAD(+) potential redox could be the causes of the gluconeogenesis inhibition. Fisetin could also prevent hyperglycemia by decreasing glycogen breakdown or blocking the glycogenolytic action of hormones.
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Rauter AP, Martins A, Borges C, Mota-Filipe H, Pinto R, Sepodes B, Justino J. Antihyperglycaemic and protective effects of flavonoids on streptozotocin-induced diabetic rats. Phytother Res 2010; 24 Suppl 2:S133-8. [DOI: 10.1002/ptr.3017] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Halbwirth H. The creation and physiological relevance of divergent hydroxylation patterns in the flavonoid pathway. Int J Mol Sci 2010; 11:595-621. [PMID: 20386656 PMCID: PMC2852856 DOI: 10.3390/ijms11020595] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2009] [Revised: 01/27/2010] [Accepted: 01/28/2010] [Indexed: 11/25/2022] Open
Abstract
Flavonoids and biochemically-related chalcones are important secondary metabolites, which are ubiquitously present in plants and therefore also in human food. They fulfill a broad range of physiological functions in planta and there are numerous reports about their physiological relevance for humans. Flavonoids have in common a basic C(6)-C(3)-C(6) skeleton structure consisting of two aromatic rings (A and B) and a heterocyclic ring (C) containing one oxygen atom, whereas chalcones, as the intermediates in the formation of flavonoids, have not yet established the heterocyclic C-ring. Flavonoids are grouped into eight different classes, according to the oxidative status of the C-ring. The large number of divergent chalcones and flavonoid structures is from the extensive modification of the basic molecules. The hydroxylation pattern influences physiological properties such as light absorption and antioxidative activity, which is the base for many beneficial health effects of flavonoids. In some cases antiinfective properties are also effected.
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Affiliation(s)
- Heidi Halbwirth
- Institut für Verfahrenstechnik, Umwelttechnik und Technische Biowissenschaften, Technische Universität Wien, Getreidemarkt 9/1665, A-1060 Wien, Austria; E-Mail:
; Tel.: +43-1-58801-17311; Fax: +43-1-58801-17399
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46
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Kim JH, Jang YO, Kim BT, Hwang KJ, Lee JC. Induction of caspase-dependent apoptosis in melanoma cells by the synthetic compound (E)-1-(3,4-dihydroxyphenethyl)-3-styrylurea. BMB Rep 2009; 42:806-11. [DOI: 10.5483/bmbrep.2009.42.12.806] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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47
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Liu G, Xu Z, Chen J, Lang G, Tian Q, Shen Y, Chen B, Yao S. On-line strategies for the identification of unknown flavone glycosides in Dracocephalum tanguticum Maxim. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 877:2545-50. [DOI: 10.1016/j.jchromb.2009.06.040] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Revised: 06/24/2009] [Accepted: 06/24/2009] [Indexed: 11/26/2022]
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48
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Kuriyama C, Kamiyama O, Ikeda K, Sanae F, Kato A, Adachi I, Imahori T, Takahata H, Okamoto T, Asano N. In vitro inhibition of glycogen-degrading enzymes and glycosidases by six-membered sugar mimics and their evaluation in cell cultures. Bioorg Med Chem 2008; 16:7330-6. [PMID: 18595718 DOI: 10.1016/j.bmc.2008.06.026] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Revised: 06/12/2008] [Accepted: 06/12/2008] [Indexed: 10/21/2022]
Abstract
We investigated in vitro inhibition of mammalian carbohydrate-degrading enzymes by six-membered sugar mimics and their evaluation in cell cultures. 1-Deoxynojirimycin (DNJ) showed no significant inhibition toward glycogen phosphorylase (GP) but was a potent inhibitor of another glycogen-degrading enzyme, amylo-1,6-glucosidase (1,6-GL), with an IC(50) value of 0.16 microM. In primary rat hepatocytes, the inhibition of glycogen breakdown by DNJ reached plateau at 100 microM with 25% inhibition and then remained unchanged. The potent GP inhibitor 1,4-dideoxy-1,4-imino-D-arabinitol (D-AB1) inhibited hepatic glucose production with an IC(50) value of about 9 microM and the inhibition by D-AB1 was further enhanced in the presence of DNJ. DNJ and alpha-homonojirimycin (HNJ) are very potent inhibitors of rat intestinal maltase, with IC(50) values of 0.13 and 0.08 microM, respectively, and also showed a similar strong inhibition toward maltase in Caco-2 cell model system, with IC(50) value of 0.05 and 0.10 microM, respectively. D-Isofagomine (D-IFG) and L-IFG are competitive and noncompetitive inhibitors of human lysosomal beta-glucosidase (beta-GL), respectively, with K(i) values of 8.4 nM and 6.9 microM. D-IFG increased intracellular beta-GL activity by twofold at 10 microM in Gaucher N370S cell line as an 'active-site-specific' chaperone, and surprisingly a noncompetitive inhibitor L-IFG also increased intracellular beta-GL activity by 1.6-fold at 500 microM.
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Affiliation(s)
- Chinami Kuriyama
- Faculty of Pharmaceutical Sciences, Hokuriku University, Ho-3 Kanagawa-machi, Kanazawa 920-1181, Japan
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