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Carmo F, Silva C, Martel F. Inhibition of Glutamine Cellular Uptake Contributes to the Cytotoxic Effect of Xanthohumol in Triple-Negative Breast Cancer Cells. Nutr Cancer 2022; 74:3413-3430. [PMID: 35594207 DOI: 10.1080/01635581.2022.2076889] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Breast cancer constitutes the most incident cancer and one of the most common causes of cancer-related death. "Glutamine addiction", an important metabolic feature of cancer cells, is dependent on supply of this amino acid from external sources. In this study, the effect of several polyphenols (catechin, epicatechin, EGCG, catechin:lysine, naringenin, hesperidin, malvidin, delphinidin, kaempferol, quercetin, rutin, myricetin, resveratrol, xanthohumol, and chrysin) upon glutamine (3H-GLN) uptake by human breast epithelial adenocarcinoma cell lines with distinct characteristics (MCF-7 and MDA-MB-231) was assessed.Several polyphenols interfere with 3H-GLN uptake by both cell lines. Xanthohumol markedly decreases total and Na+-dependent 3H-GLN uptake and showed a cytotoxic and anti-proliferative effect in MDA-MB-231 cells. Xanthohumol is as an uncompetitive inhibitor of Na+-dependent 3H-GLN uptake and inhibits GPNA (L-γ-glutamyl-p-nitroanilide)-sensitive, both ASCT2 (alanine, serine, cysteine transporter 2)-mediated and non-ASCT2-mediated 3H-GLN uptake. Xanthohumol does not interfere with the transcription rates of ASCT2. The cytotoxic effect of xanthohumol, but not its anti-proliferative effect, is GPNA-sensitive and related to ASCT2 inhibition. Combination of xanthohumol with the breast cancer chemotherapeutic agent doxorubicin results in an additive anti-proliferative, but not cytotoxic effect.We conclude that targeting glutamine uptake might constitute a potential interesting strategy for triple-negative breast cancer.
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Affiliation(s)
- F Carmo
- Unit of Biochemistry, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal.,Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - C Silva
- Unit of Biochemistry, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal.,Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - F Martel
- Unit of Biochemistry, Department of Biomedicine, Faculty of Medicine, University of Porto, Porto, Portugal.,Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Porto, Portugal
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Andrade N, Araújo JR, Correia-Branco A, Carletti JV, Martel F. Effect of dietary polyphenols on fructose uptake by human intestinal epithelial (Caco-2) cells. J Funct Foods 2017. [DOI: 10.1016/j.jff.2017.07.032] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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3
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Meireles M, Moura E, Vieira-Coelho MA, Santos-Buelga C, Gonzalez-Manzano S, Dueñas M, Mateus N, Faria A, Calhau C. Flavonoids as dopaminergic neuromodulators. Mol Nutr Food Res 2016; 60:495-501. [PMID: 26582321 DOI: 10.1002/mnfr.201500557] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 10/28/2015] [Accepted: 10/31/2015] [Indexed: 12/25/2022]
Abstract
SCOPE The present study aimed to characterize and evaluate flavonoids effects on organic cation uptake in neuronal cells. METHODS AND RESULTS Uptake experiments were conducted using radiolabeled methyl-4-phenylpyridinuim ([(3) H]-MPP(+) ), in human neuronal dopaminergic cells, SH-SY5Y. Catechin did not alter [(3) H]-MPP(+) uptake, however its metabolite 4'-methyl-catechin decreased it by almost 50%. Epicatechin and its methylated metabolites also decreased [(3) H]-MPP(+) uptake. Interestingly, the quercetin flavonol and its metabolite conjugated with glucuronic acid, as well as the flavanones naringenin and hesperitin, increased [(3) H]-MPP(+) uptake. CONCLUSION These results showed that different classes of flavonoids, as well as its metabolites, differently influence neuronal organic cation uptake. Several xeno- and endobiotics, including neurotransmitters, are organic cations. Specific food recommendations may be beneficial in pathological conditions where levels of neurotransmitters, as dopamine, are either increased or decreased.
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Affiliation(s)
- Manuela Meireles
- Department of Biochemistry, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Eduardo Moura
- Department of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Porto, Portugal
| | | | - Celestino Santos-Buelga
- Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno s/n, Salamanca, Espanha
| | - Susana Gonzalez-Manzano
- Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno s/n, Salamanca, Espanha
| | - Montserrat Dueñas
- Unidad de Nutrición y Bromatología, Facultad de Farmacia, Universidad de Salamanca, Campus Miguel de Unamuno s/n, Salamanca, Espanha
| | - Nuno Mateus
- REQUIMTE/LAQV, Faculty of Sciences, University of Porto, Porto, Portugal
| | - Ana Faria
- Department of Biochemistry, Faculty of Medicine, University of Porto, Porto, Portugal.,REQUIMTE/LAQV, Faculty of Sciences, University of Porto, Porto, Portugal.,Faculty of Nutrition and Food Sciences, University of Porto, Porto, Portugal
| | - Conceição Calhau
- Department of Biochemistry, Faculty of Medicine, University of Porto, Porto, Portugal.,CINTESIS - Center for Research in Health Technologies and Information Systems, Faculty of Medicine, University of Porto, Porto, Portugal
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Hussain SA, Sulaiman AA, Alhaddad H, Alhadidi Q. Natural polyphenols: Influence on membrane transporters. JOURNAL OF COMPLEMENTARY MEDICINE RESEARCH 2016; 5:97-104. [PMID: 27069731 PMCID: PMC4805155 DOI: 10.5455/jice.20160118062127] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 01/18/2016] [Indexed: 02/02/2023]
Abstract
Accumulated evidence has focused on the use of natural polyphenolic compounds as nutraceuticals since they showed a wide range of bioactivities and exhibited protection against variety of age-related disorders. Polyphenols have variable potencies to interact, and hence alter the activities of various transporter proteins, many of them classified as anion transporting polypeptide-binding cassette transporters like multidrug resistance protein and p-glycoprotein. Some of the efflux transporters are, generally, linked with anticancer and antiviral drug resistance; in this context, polyphenols may be beneficial in modulating drug resistance by increasing the efficacy of anticancer and antiviral drugs. In addition, these effects were implicated to explain the influence of dietary polyphenols on drug efficacy as result of food-drug interactions. However, limited data are available about the influence of these components on uptake transporters. Therefore, the objective of this article is to review the potential efficacies of polyphenols in modulating the functional integrity of uptake transporter proteins, including those terminated the effect of neurotransmitters, and their possible influence in neuropharmacology.
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Affiliation(s)
- Saad Abdulrahman Hussain
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Baghdad, Baghdad, Iraq
| | - Amal Ajaweed Sulaiman
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Baghdad, Baghdad, Iraq
| | - Hasan Alhaddad
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Baghdad, Baghdad, Iraq
| | - Qasim Alhadidi
- Department of Medicinal and Biological Chemistry, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, 3000 Arlington Avenue, Toledo, OH, 43614, USA
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5
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Jaiyen C, Jutabha P, Anzai N, Lungkaphin A, Soodvilai S, Srimaroeng C. Interaction of green tea catechins with renal organic cation transporter 2. Xenobiotica 2015; 46:641-650. [PMID: 26576923 DOI: 10.3109/00498254.2015.1107785] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
1. Green tea extract (GTE) and EGCG have previously shown to increase the uptake of MPP+ into Caco-2 cells. However, whether GTE and its derivatives interact with renal basolateral organic cation transporter 2 (Oct2) which plays a crucial role for cationic clearance remains unknown. Thus, this study assessed the potential of drug-green tea (GT) catechins and its derivatives interactions with rat Oct2 using renal cortical slices and S2 stably expressing rat Oct2 (S2rOct2). 2. Both GTE and ECG inhibited MPP+ uptake in renal slices in a concentration-dependent manner (IC50 = 2.71 ± 0.360 mg/ml and 0.87 ± 0.151 mM), and this inhibitory effect was reversible. Inhibition of [3H]MPP+ transport in S2rOct2 by either GTE or ECG (IC50 = 1.90 ± 0.087 mg/ml and 1.67 ± 0.088 mM) was also observed. 3. The weak and reversible interactions of GTE and ECG with rOct2 indicate that consumption of GT beverages could not interfere with cationic drugs secreted via renal OCT2 in humans. However, the rise of therapeutic use of GTE and ECG might have to take into account the significant possibility of adverse drug-green tea catechins interactions which could alter renal organic cation drug clearance.
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Affiliation(s)
- Chaliya Jaiyen
- a Department of Physiology , Faculty of Medicine, Chiang Mai University , Chiang Mai , Thailand.,b Department of Pharmacology and Toxicology , Dokkyo Medical University, School of Medicine , Tochigi , Japan , and
| | - Promsuk Jutabha
- b Department of Pharmacology and Toxicology , Dokkyo Medical University, School of Medicine , Tochigi , Japan , and
| | - Naohiko Anzai
- b Department of Pharmacology and Toxicology , Dokkyo Medical University, School of Medicine , Tochigi , Japan , and
| | - Anusorn Lungkaphin
- a Department of Physiology , Faculty of Medicine, Chiang Mai University , Chiang Mai , Thailand
| | - Sunhapas Soodvilai
- c Department of Physiology , Faculty of Science, Mahidol University , Bangkok , Thailand
| | - Chutima Srimaroeng
- a Department of Physiology , Faculty of Medicine, Chiang Mai University , Chiang Mai , Thailand
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6
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Norberto S, Silva S, Meireles M, Faria A, Pintado M, Calhau C. Blueberry anthocyanins in health promotion: A metabolic overview. J Funct Foods 2013. [DOI: 10.1016/j.jff.2013.08.015] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
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7
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Marques C, Teixeira D, Cunha A, Meireles M, Pestana D, Keating E, Calhau C, Monteiro R, Faria A. Methotrexate enhances 3T3-L1 adipocytes hypertrophy. Cell Biol Toxicol 2013; 29:293-302. [PMID: 23955089 DOI: 10.1007/s10565-013-9255-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 08/05/2013] [Indexed: 11/26/2022]
Abstract
Methotrexate (MTX) is broadly used in the treatment of chronic inflammatory diseases such as rheumatoid arthritis (RA). The prevalence of metabolic syndrome (MeS) in patients with this condition is relatively high. Given the importance of adipose tissue in the development of obesity metabolic complications, this study aimed to investigate the effect of methotrexate on preadipocyte proliferation, adipogenesis, and glucose uptake by adipocytes. 3T3-L1 preadipocytes proliferation was evaluated by sulforhodamine B staining and (3)H-thymidine incorporation, after 24 or 48 h of treatment with MTX (0.1 and 10 μM). Preadipocytes were induced to differentiate with an appropriate adipogenic cocktail in the presence or absence of MTX. Adipogenesis was determined by measuring lipid accumulation after staining with oil red O. (3)H-Deoxyglucose ((3)H-DG) uptake was determined by liquid scintillation counting. MTX treatment reduced culture protein content in a concentration-dependent manner and (3)H-thymidine incorporation (P < 0.05). MTX (0.1 μM) treatment increased lipid accumulation and basal (3)H-DG uptake by adipocytes (P < 0.05). In 0.1 μM MTX-treated adipocytes, insulin stimulation did not result in an increase of (3)H-DG uptake, contrarily to what was observed in control cells. These results demonstrate that methotrexate interferes with adipocyte proliferation and promotes the hypertrophic growth of adipocytes. These molecular effects may have implications on metabolic profile of RA patients treated with MTX.
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Affiliation(s)
- Cláudia Marques
- Departamento de Bioquímica (U38-FCT), Faculdade de Medicina, Universidade do Porto, Alameda Prof. Hernâni Monteiro, 4200-319, Oporto, Portugal.
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Chin AC, Baskin LB. Effect of Herbal Supplement–Drug Interactions on Therapeutic Drug Monitoring. Ther Drug Monit 2012. [DOI: 10.1016/b978-0-12-385467-4.00019-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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9
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Yang J, Han Y, Sun H, Chen C, He D, Guo J, Yu C, Jiang B, Zhou L, Zeng C. (-)-Epigallocatechin gallate suppresses proliferation of vascular smooth muscle cells induced by high glucose by inhibition of PKC and ERK1/2 signalings. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:11483-11490. [PMID: 21973165 DOI: 10.1021/jf2024819] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Proliferation of vascular smooth muscle cells (VSMCs) plays an important role in the development and progression of diabetes-related vascular complications. (-)-Epigallocatechin gallate (EGCG), the major catechin derived from green tea, is able to exert antidiabetes effects in animal models. However, it is not known whether or not EGCG inhibits VSMC proliferation induced by high glucose. This study tested the hypothesis that EGCG might have an inhibitory effect on VSMC proliferation induced by high glucose. VSMC proliferation was determined by [(3)H]-thymidine incorporation and uptake of 3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide (MTT). Extracellular signal-regulated kinase (ERK) 1/2 phosphorylation was determined by immunoblotting, and ERK 1/2 activity was detected by measuring the ability to phosphorylate its substrate Elk-1. Glucose increased VSMC proliferation in a concentration-dependent manner, which was reduced in the presence of EGCG. VSMC proliferation mediated by high glucose (30 mM) was involved in protein kinase C (PKC) and ERK1/2 signalings, because its effect was blocked by PKC inhibitor (PKC inhibitor 19-31) and ERK1/2 inhibitor (PD98059). Pretreatment of VSMCs with EGCG significantly inhibited the stimulatory effect of high glucose on PKC and ERK1/2 activation, followed by attenuation of its downstream transcription factor Elk-1 phosphorylation. Taken together, these results suggest that EGCG could suppress VSMC proliferation induced by high glucose by inhibition of PKC and ERK1/2 signalings in VSMCs, which indicates that EGCG might be a possible medicine to reduce vascular complications in diabetes.
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Affiliation(s)
- Jian Yang
- Department of Nutrition, Daping Hospital, The Third Military Medical University, Chongqing, 400042 People's Republic of China
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10
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Effect of polyphenols on the intestinal and placental transport of some bioactive compounds. Nutr Res Rev 2010; 23:47-64. [DOI: 10.1017/s0954422410000053] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Polyphenols are a group of widely distributed phytochemicals present in most foods of vegetable origin. A growing number of biological effects have been attributed to these molecules in the past few years and only recently has their interference with the transport capacity of epithelial barriers received attention. This review will present data obtained concerning the effect of polyphenols upon the transport of some compounds (organic cations, glucose and the vitamins thiamin and folic acid) at the intestinal and placental barriers. Important conclusions can be drawn: (i) different classes of polyphenols affect transport of these bioactive compounds at the intestinal epithelia and the placenta; (ii) different compounds belonging to the same phenolic family often possess opposite effects upon transport of a given molecule; (iii) the acute and chronic/short-term and long-term exposures to polyphenols do not produce parallel results and, therefore, care should be taken when extrapolating results; (iv) the effect of polyphenolics in combination may be very different from the expected ones taking into account the effect of each of these compounds alone, and so care should be taken when speculating on the effect of a drink based on the effect of one component only; (v) care should be taken in drawing conclusions for alcoholic beverages from results obtained with ethanol alone. Although most of the data reviewed in the present paper refer to in vitro experiments with cell-culture systems, these studies raise a concern about possible changes in the bioavailability of substrates upon concomitant ingestion of polyphenols.
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11
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Lovejoy KS, Lippard SJ. Non-traditional platinum compounds for improved accumulation, oral bioavailability, and tumor targeting. Dalton Trans 2009:10651-9. [PMID: 20023892 PMCID: PMC2800312 DOI: 10.1039/b913896j] [Citation(s) in RCA: 190] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The five platinum anticancer compounds currently in clinical use conform to structure-activity relationships formulated (M. J. Cleare and J. D. Hoeschele, Bioinorg. Chem., 1973, 2, 187-210) shortly after the discovery that cis-diamminedichloroplatinum(II), cisplatin, has antitumor activity in mice. These compounds are neutral platinum(II) species with two am(m)ine ligands or one bidentate chelating diamine and two additional ligands that can be replaced by water through aquation reactions. The resulting cations ultimately form bifunctional adducts on DNA. Information about the chemistry of these platinum compounds and correlations of their structures with anticancer activity have provided guidance for the design of novel anticancer drug candidates based on the proposed mechanisms of action. This article discusses advances in the synthesis and evaluation of such non-traditional platinum compounds, including cationic and tumor-targeting constructs.
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Affiliation(s)
- Katherine S Lovejoy
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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12
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pH dependent efflux of methamphetamine derivatives and their reversal through human Caco-2 cell monolayers. Eur J Pharmacol 2008; 592:7-12. [DOI: 10.1016/j.ejphar.2008.06.090] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Revised: 06/18/2008] [Accepted: 06/27/2008] [Indexed: 01/16/2023]
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13
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Faria A, Pestana D, Monteiro R, Oliveira J, Freitas VD, Azevedo I, Calhau C, Mateus N. Influence of anthocyanins and derivative pigments from blueberry (Vaccinium myrtillus) extracts on MPP+ intestinal uptake: A structure–activity approach. Food Chem 2008. [DOI: 10.1016/j.foodchem.2008.01.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lemos C, Peters GJ, Jansen G, Martel F, Calhau C. Modulation of folate uptake in cultured human colon adenocarcinoma Caco-2 cells by dietary compounds. Eur J Nutr 2007; 46:329-36. [PMID: 17712586 DOI: 10.1007/s00394-007-0670-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2006] [Accepted: 06/28/2007] [Indexed: 01/12/2023]
Abstract
Folate is a water-soluble B vitamin with a crucial role in the synthesis and methylation of DNA and in the metabolism of several amino acids. In the present study we investigated whether beverages like wine, beer and tea, or some of their specific constituents, affect the intestinal uptake of (3)H-folic acid or (3)H-methotrexate (an antifolate). All tested beverages significantly inhibited the uptake of (3)H-folic acid by Caco-2 cells. Most of these beverages, with the exception of wines (not tested), also inhibited (3)H-methotrexate uptake in these cells. Additionally, ethanol, when tested separately, inhibited the uptake of both compounds. Some of the tested phenolic compounds, namely myricetin, epigallocatechin gallate (EGCG) and isoxanthohumol, markedly inhibited (3)H-folic acid uptake. Myricetin and EGCG also had a concentration-dependent inhibitory effect upon the uptake of (3)H-methotrexate by Caco-2 cells. Resveratrol, quercetin and kaempferol were able to inhibit the transport of both compounds, but only in the concentration of 100 microM. In conclusion, dietary constituents may impact on intestinal folate uptake, as here shown for phenolic compounds.
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Affiliation(s)
- Clara Lemos
- Department of Biochemistry (U38-FCT), Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal.
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Intra J, Kuo SM. Physiological levels of tea catechins increase cellular lipid antioxidant activity of vitamin C and vitamin E in human intestinal caco-2 cells. Chem Biol Interact 2007; 169:91-9. [PMID: 17603031 PMCID: PMC1965493 DOI: 10.1016/j.cbi.2007.05.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2007] [Revised: 05/24/2007] [Accepted: 05/25/2007] [Indexed: 10/23/2022]
Abstract
Oxidative stress has been linked to the development of various chronic diseases. Vegetables and fruits, which contain polyphenols, were shown to have protective effects. (-)-Epigallocatechin-3-gallate (EGCG), a polyphenol abundant in tea, has been shown to have antioxidant activities in cell-free conditions and this study focused on the effect of cellular EGCG. Using an intestinal cell model to examine the oxidative stress induced by hydroxyl radicals, we report here that physiological concentrations (0.1-1 microM) of EGCG have dose- and incubation duration-dependent cell-associated lipid antioxidant activity (measuring malondialdehyde production). Vitamin E and vitamin C at 10-40 microM also showed cell-associated lipid antioxidant activities under shorter incubation durations. When EGCG was included in the incubation with vitamin E or C, more antioxidant activities were consistently observed than when vitamins were added alone. Catechin (widely present in fruits and vegetables) at 1 microM also significantly increased the antioxidant activity of vitamins E and C. Previous studies examining cell-associated activity of EGCG mainly focused on the 10-100 microM concentration range. Our results suggest that although the physiological level (0.1-1 microM) of dietary catechins is much lower than that of vitamins, they further contribute to the total antioxidant capacity even in the presence of vitamins.
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Affiliation(s)
- Janjira Intra
- Department of Exercise and Nutrition Sciences, University at Buffalo, 15 Farber Hall, Buffalo, NY 14214, USA
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Ulanowska K, Piosik J, Gwizdek-Wiśniewska A, Wegrzyn G. Impaired mutagenic activities of MPDP(+) (1-methyl-4-phenyl-2,3-dihydropyridinium) and MPP(+) (1-methyl-4-phenylpyridinium) due to their interactions with methylxanthines. Bioorg Med Chem 2007; 15:5150-7. [PMID: 17533133 DOI: 10.1016/j.bmc.2007.05.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2006] [Revised: 05/04/2007] [Accepted: 05/11/2007] [Indexed: 11/24/2022]
Abstract
MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) is a neurotoxin causing symptoms that resemble those observed in patients suffering from Parkinson's disease. However, in animal or human organisms, MPTP is converted to MPDP(+) (1-methyl-4-phenyl-2,3-dihydropyridinium) and further to MPP(+) (1-methyl-4-phenylpyridinium); the latter compound is the actual neurotoxin. In this report, we demonstrate that MPDP(+) and MPP(+) can form stacking complexes with methylxanthines (caffeine and penthoxifylline), which leads to significant impairment of the biological activity of these toxins (as measured by their mutagenicity).
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Affiliation(s)
- Katarzyna Ulanowska
- Department of Molecular Biology, University of Gdańsk, Kładki 24, Gdańsk, Poland
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Faria A, Mateus N, de Freitas V, Calhau C. Modulation of MPP+uptake by procyanidins in Caco-2 cells: Involvement of oxidation/reduction reactions. FEBS Lett 2005; 580:155-60. [PMID: 16364314 DOI: 10.1016/j.febslet.2005.11.068] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 11/15/2005] [Accepted: 11/27/2005] [Indexed: 11/26/2022]
Abstract
It is becoming increasingly evident that the absorption of certain nutrients and drugs and their effects are largely influenced by the concomitant ingestion of other substances. As various xeno- and endobiotics belong to the class of organic cations, the aim of this work was to study the modulation of the intestinal apical uptake of organic cations by diet procyanidins. Five procyanidin fractions with different structural complexity were obtained after fractionation of a grape seed extract. The effect of these compounds on 1-methyl-4-phenylpyridinium (MPP+) uptake was evaluated in Caco-2 cells. Apical uptake of 3H-MPP+ by Caco-2 cells was increased by a 60 min exposure to 600 microg ml(-1) of procyanidin fractions, that increase being positively related with procyanidins structural complexity. It was verified that 3H-MPP+ uptake increased with preincubation time. It was speculated that procyanidins were oxidized during preincubation, this change could interfered with transport activity. Tested oxidizing agents showed that the redox state of the transporter could affect its activity. Additionally, trans-stimulation experiments showed that catechin and fraction I (the simpler fraction) can use the same transporter as MPP+. The results are compatible with the hypothesis of these compounds being competitive inhibitors of MPP+ transport. In conclusion, procyanidins are capable to modulate MPP+ apical uptake in Caco-2 cells, this transport being most probably modulated through oxidation-reduction phenomena. Interactions between these compounds and drugs present in the diet may affect their absorption and bioavailability. Both the concentration and complexity of the procyanidin compounds should be taken into account in medical practice.
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Affiliation(s)
- Ana Faria
- Department of Biochemistry (U38-FCT), Faculty of Medicine of the University of Porto, Al. Prof. Hernani Monteiro, 4200-319 Porto, Portugal
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