1
|
Kakavas S, Karayiannis D, Mastora Z. The Complex Interplay between Immunonutrition, Mast Cells, and Histamine Signaling in COVID-19. Nutrients 2021; 13:nu13103458. [PMID: 34684460 PMCID: PMC8537261 DOI: 10.3390/nu13103458] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/17/2021] [Accepted: 09/27/2021] [Indexed: 12/23/2022] Open
Abstract
There is an ongoing need for new therapeutic modalities against SARS-CoV-2 infection. Mast cell histamine has been implicated in the pathophysiology of COVID-19 as a regulator of proinflammatory, fibrotic, and thrombogenic processes. Consequently, mast cell histamine and its receptors represent promising pharmacological targets. At the same time, nutritional modulation of immune system function has been proposed and is being investigated for the prevention of COVID-19 or as an adjunctive strategy combined with conventional therapy. Several studies indicate that several immunonutrients can regulate mast cell activity to reduce the de novo synthesis and/or release of histamine and other mediators that are considered to mediate, at least in part, the complex pathophysiology present in COVID-19. This review summarizes the effects on mast cell histamine of common immunonutrients that have been investigated for use in COVID-19.
Collapse
Affiliation(s)
- Sotirios Kakavas
- Critical Care Department, “Sotiria” General Hospital of Chest Diseases, 152 Mesogeion Avenue, 11527 Athens, Greece;
| | - Dimitrios Karayiannis
- Department of Clinical Nutrition, Evangelismos General Hospital of Athens, Ypsilantou 45-47, 10676 Athens, Greece
- Correspondence: ; Tel.: +30-213-2045035; Fax: +30-213-2041385
| | - Zafeiria Mastora
- First Department of Critical Care Medicine and Pulmonary Services, Evangelismos General Hospital, National and Kapodistrian University of Athens, 11527 Athens, Greece;
| |
Collapse
|
2
|
Mast Cell Regulation and Irritable Bowel Syndrome: Effects of Food Components with Potential Nutraceutical Use. Molecules 2020; 25:molecules25184314. [PMID: 32962285 PMCID: PMC7570512 DOI: 10.3390/molecules25184314] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/12/2020] [Accepted: 09/17/2020] [Indexed: 12/12/2022] Open
Abstract
Mast cells are key actors in inflammatory reactions. Upon activation, they release histamine, heparin and nerve growth factor, among many other mediators that modulate immune response and neuron sensitization. One important feature of mast cells is that their population is usually increased in animal models and biopsies from patients with irritable bowel syndrome (IBS). Therefore, mast cells and mast cell mediators are regarded as key components in IBS pathophysiology. IBS is a common functional gastrointestinal disorder affecting the quality of life of up to 20% of the population worldwide. It is characterized by abdominal pain and altered bowel habits, with heterogeneous phenotypes ranging from constipation to diarrhea, with a mixed subtype and even an unclassified form. Nutrient intake is one of the triggering factors of IBS. In this respect, certain components of the daily food, such as fatty acids, amino acids or plant-derived substances like flavonoids, have been described to modulate mast cells' activity. In this review, we will focus on the effect of these molecules, either stimulatory or inhibitory, on mast cell degranulation, looking for a nutraceutical capable of decreasing IBS symptoms.
Collapse
|
3
|
Hagemann PM, Nsiah-Dosu S, Hundt JE, Hartmann K, Orinska Z. Modulation of Mast Cell Reactivity by Lipids: The Neglected Side of Allergic Diseases. Front Immunol 2019; 10:1174. [PMID: 31191542 PMCID: PMC6549522 DOI: 10.3389/fimmu.2019.01174] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Accepted: 05/08/2019] [Indexed: 12/20/2022] Open
Abstract
Mast cells (MCs) have long been mainly regarded as effector cells in IgE-associated allergic disorders with potential immunoregulatory roles. Located close to the allergen entry sites in the skin and mucosa, MCs can capture foreign substances such as allergens, toxins, or noxious substances and are exposed to the danger signals produced by epithelial cells. MC reactivity shaped by tissue-specific factors is crucial for allergic responses ranging from local skin reactions to anaphylactic shock. Development of Th2 response leading to allergen-specific IgE production is a prerequisite for MC sensitization and induction of FcεRI-mediated MC degranulation. Up to now, IgE production has been mainly associated with proteins, whereas lipids present in plant pollen grains, mite fecal particles, insect venoms, or food have been largely overlooked regarding their immunostimulatory and immunomodulatory properties. Recent studies, however, have now demonstrated that lipids affect the sensitization process by modulating innate immune responses of epithelial cells, dendritic cells, and NK-T cells and thus crucially contribute to the outcome of sensitization. Whether and how lipids affect also MC effector functions in allergic reactions has not yet been fully clarified. Here, we discuss how lipids can affect MC responses in the context of allergic inflammation. Direct effects of immunomodulatory lipids on MC degranulation, changes in local lipid composition induced by allergens themselves and changes in lipid transport affecting MC reactivity are possible mechanisms by which the function of MC might be modulated.
Collapse
Affiliation(s)
- Philipp M Hagemann
- Division of Experimental Pneumology, Research Center Borstel, Leibniz Lungenzentrum, Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
| | | | | | - Karin Hartmann
- Department of Dermatology, University of Luebeck, Luebeck, Germany.,Division of Allergy, Department of Dermatology, University of Basel, Basel, Switzerland
| | - Zane Orinska
- Division of Experimental Pneumology, Research Center Borstel, Leibniz Lungenzentrum, Airway Research Center North, German Center for Lung Research (DZL), Borstel, Germany
| |
Collapse
|
4
|
Li XI, Dong Z, Zhang F, Dong J, Zhang Y. Vitamin E slows down the progression of osteoarthritis. Exp Ther Med 2016; 12:18-22. [PMID: 27347011 DOI: 10.3892/etm.2016.3322] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 04/11/2016] [Indexed: 12/24/2022] Open
Abstract
Osteoarthritis is a chronic degenerative joint disorder with the characteristics of articular cartilage destruction, subchondral bone alterations and synovitis. Clinical signs and symptoms of osteoarthritis include pain, stiffness, restricted motion and crepitus. It is the major cause of joint dysfunction in developed nations and has enormous social and economic consequences. Current treatments focus on symptomatic relief, however, they lack efficacy in controlling the progression of this disease, which is a leading cause of disability. Vitamin E is safe to use and may delay the progression of osteoarthritis by acting on several aspects of the disease. In this review, how vitamin E may promote the maintenance of skeletal muscle and the regulation of nucleic acid metabolism to delay osteoarthritis progression is explored. In addition, how vitamin E may maintain the function of sex organs and the stability of mast cells, thus conferring a greater resistance to the underlying disease process is also discussed. Finally, the protective effect of vitamin E on the subchondral vascular system, which decreases the reactive remodeling in osteoarthritis, is reviewed.
Collapse
Affiliation(s)
- X I Li
- Department of Orthopaedic Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, P.R. China
| | - Zhongli Dong
- Department of Orthopaedic Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, P.R. China
| | - Fuhou Zhang
- Department of Orthopaedic Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, P.R. China
| | - Junjie Dong
- Department of Orthopaedic Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, P.R. China
| | - Yuan Zhang
- Department of Orthopaedic Surgery, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan 650032, P.R. China
| |
Collapse
|
5
|
Sridharan V, Tripathi P, Sharma S, Corry PM, Moros EG, Singh A, Compadre CM, Hauer-Jensen M, Boerma M. Effects of late administration of pentoxifylline and tocotrienols in an image-guided rat model of localized heart irradiation. PLoS One 2013; 8:e68762. [PMID: 23894340 PMCID: PMC3718790 DOI: 10.1371/journal.pone.0068762] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 06/02/2013] [Indexed: 01/15/2023] Open
Abstract
Radiation-induced heart disease (RIHD) is a long-term side effect of radiotherapy of intrathoracic, chest wall and breast tumors when radiation fields encompass all or part of the heart. Previous studies have shown that pentoxifylline (PTX) in combination with α-tocopherol reduced manifestations of RIHD in rat models of local heart irradiation. The relative contribution of PTX and α-tocopherol to these beneficial effects are not known. This study examined the effects of PTX alone or in combination with tocotrienols, forms of vitamin E with potential potent radiation mitigation properties. Rats received localized X-irradiation of the heart with an image-guided irradiation technique. At 3 months after irradiation rats received oral treatment with vehicle, PTX, or PTX in combination with a tocotrienol-enriched formulation. At 6 months after irradiation, PTX-treated rats showed arrhythmia in 5 out of 14 animals. PTX alone or in combination with tocotrienols did not alter cardiac radiation fibrosis, left ventricular protein expression of the endothelial markers von Willebrand factor and neuregulin-1, or phosphorylation of the signal mediators Akt, Erk1/2, or PKCα. On the other hand, tocotrienols reduced cardiac numbers of mast cells and macrophages, but enhanced the expression of tissue factor. While this new rat model of localized heart irradiation does not support the use of PTX alone, the effects of tocotrienols on chronic manifestations of RIHD deserve further investigation.
Collapse
Affiliation(s)
- Vijayalakshmi Sridharan
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Preeti Tripathi
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Sunil Sharma
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Peter M. Corry
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Eduardo G. Moros
- Department of Radiation Oncology, Moffitt Cancer Center and Research Institute, Tampa, Florida, United States of America
| | - Awantika Singh
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Cesar M. Compadre
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Martin Hauer-Jensen
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- Surgical Service, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, United States of America
| | - Marjan Boerma
- Division of Radiation Health, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| |
Collapse
|
6
|
Aan GJ, Zainudin MSA, Karim NA, Ngah WZW. Effect of the tocotrienol-rich fraction on the lifespan and oxidative biomarkers in Caenorhabditis elegans under oxidative stress. Clinics (Sao Paulo) 2013; 68:599-604. [PMID: 23778402 PMCID: PMC3654308 DOI: 10.6061/clinics/2013(05)04] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 12/02/2012] [Accepted: 01/04/2013] [Indexed: 01/10/2023] Open
Abstract
OBJECTIVE This study was performed to determine the effect of the tocotrienol-rich fraction on the lifespan and oxidative status of C. elegans under oxidative stress. METHOD Lifespan was determined by counting the number of surviving nematodes daily under a dissecting microscope after treatment with hydrogen peroxide and the tocotrienol-rich fraction. The evaluated oxidative markers included lipofuscin, which was measured using a fluorescent microscope, and protein carbonyl and 8-hydroxy-2'-deoxyguanosine, which were measured using commercially available kits. RESULTS Hydrogen peroxide-induced oxidative stress significantly decreased the mean lifespan of C. elegans, which was restored to that of the control by the tocotrienol-rich fraction when administered before or both before and after the hydrogen peroxide. The accumulation of the age marker lipofuscin, which increased with hydrogen peroxide exposure, was decreased with upon treatment with the tocotrienol-rich fraction (p<0.05). The level of 8-hydroxy-2'-deoxyguanosine significantly increased in the hydrogen peroxide-induced group relative to the control. Treatment with the tocotrienol-rich fraction before or after hydrogen peroxide induction also increased the level of 8-hydroxy-2'-deoxyguanosine relative to the control. However, neither hydrogen peroxide nor the tocotrienol-rich fraction treatment affected the protein carbonyl content of the nematodes. CONCLUSION The tocotrienol-rich fraction restored the lifespan of oxidative stress-induced C. elegans and reduced the accumulation of lipofuscin but did not affect protein damage. In addition, DNA oxidation was increased.
Collapse
Affiliation(s)
- Goon Jo Aan
- Universiti Kebangsaan Malaysia, Department of Biochemistry, Faculty of Medicine, Kuala Lumpur City Campus, 50300 Kuala Lumpur/Malaysia.
| | | | | | | |
Collapse
|
7
|
Pie JE, Kim YR, Kim IK, Seo SH, Lee SH, Lee HR, Yoo Y, Chung JT, Youn JP, Oh M, Hwang SY, Kim MK. Correlation between nutrition intake and gene expression profiles in children with asthma. Mol Cell Toxicol 2010. [DOI: 10.1007/s13273-010-0042-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
8
|
Hemmerling J, Nell S, Kipp A, Schumann S, Deubel S, Haack M, Brigelius-Flohé R. alpha-Tocopherol enhances degranulation in RBL-2H3 mast cells. Mol Nutr Food Res 2010; 54:652-60. [PMID: 20169586 DOI: 10.1002/mnfr.200900462] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Based on the observation that 3 months alpha-tocopherol supplementation caused an up-regulation of the mRNA of vesicular transport proteins in livers of mice, the functional relevance was investigated in RBL-2H3 cells, a model for mast cell degranulation. In total, 24 h incubation with 100 muM alpha-tocopherol enhanced the basal and phorbol-12-myristyl-13-acetate/ionomycin-stimulated release of beta-hexosaminidase and cathepsin D as measured by enzymatic analysis as well as Western blotting and immunocytochemistry, respectively. beta-Tocopherol exerted the same effect, whereas alpha-tocopheryl phosphate and trolox were inactive, indicating that both the side chain and the 6-OH group at the chroman ring are essential for activation of degranulation. alpha-Tocopherol did not induce mRNA expression of soluble NSF-attachment protein receptor (soluble N-ethylmaleimide-sensitive factor-attachment protein receptor) proteins, such as N-ethylmaleimide sensitive fusion protein, complexin-2, SNAP23 or syntaxin-3, in the RBL-2H3 cell model. In view of the well known alpha-tocopherol-mediated activation of protein phosphatases, which regulate soluble NSF-attachment protein receptor activities by dephosphorylation, underlying mechanisms are discussed in terms of preventing oxidative inactivation of protein phosphatases and so far unknown functions in certain membrane domains.
Collapse
Affiliation(s)
- Jana Hemmerling
- German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany
| | | | | | | | | | | | | |
Collapse
|
9
|
Abstract
Nearly after one century of research and thousands of publications, the physiological function(s) of vitamin E remain unclear. Available evidence suggests a role in cell homeostasis that occurs through the modulation of specific signaling pathways and genes involved in proliferative, metabolic, inflammatory, and antioxidant pathways. Vitamin E presence in the human body is under close metabolic control so that only alpha-tocopherol and, to a lower extent, gamma-tocopherol are retained and delivered to tissues. Other vitamin E forms that are not retained in the body in significant amounts, exhibit responses in vitro that are different form those of alpha-tocopherol and may include tumor cell specific toxicity and apoptosis. These responses provide a therapeutic potential for these minor forms, either as such or metabolically modified, to produce bioactive metabolites. These cellular effects go beyond the properties of lipophilic antioxidant attributed to alpha-tocopherol particularly investigated for its alleged protective role in atherosclerosis or other oxidative stress conditions. Understanding signaling and gene expression effects of vitamin E could help assign a physiological role to this vitamin, which will be discussed in this review. Besides vitamin E signaling, attention will be given to tocotrienols as one of the emerging topics in vitamin E research and a critical re-examination of the most recent clinical trials will be provided together with the potential use of vitamin E in disease prevention and therapy.
Collapse
Affiliation(s)
- Francesco Galli
- Department of Internal Medicine, Laboratory of Clinical Biochemistry and Nutrition, University of Perugia, Perugia, Italy
| | | |
Collapse
|
10
|
Mabalirajan U, Aich J, Leishangthem GD, Sharma SK, Dinda AK, Ghosh B. Effects of vitamin E on mitochondrial dysfunction and asthma features in an experimental allergic murine model. J Appl Physiol (1985) 2009; 107:1285-92. [PMID: 19628725 DOI: 10.1152/japplphysiol.00459.2009] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We showed recently that IL-4 causes mitochondrial dysfunction in allergic asthma. IL-4 is also known to induce 12/15-lipoxygenase (12/15-LOX), a potent candidate molecule in asthma. Because vitamin E (Vit-E) reduces IL-4 and inhibits 12/15-LOX in vitro, here we tested the hypothesis that Vit-E may be effective in restoring key mitochondrial dysfunctions, thus alleviating asthma features in an experimental allergic murine model. Ovalbumin (OVA)-sensitized and challenged male BALB/c mice showed the characteristic features of asthma such as airway hyperresponsiveness (AHR), airway inflammation, and airway remodeling. In addition, these mice showed increase in the expression and metabolites of 12/15-LOX, reduction in the activity and expression of the third subunit of mitochondrial cytochrome-c oxidase, and increased cytochrome c in lung cytosol, which indicate that OVA sensitization and challenge causes mitochondrial dysfunction. Vit-E was administered orally to these mice, and 12/15-LOX expression, key mitochondrial functions, ultrastructural changes of mitochondria in bronchial epithelia, and asthmatic parameters were determined. Vit-E treatment reduced AHR, Th2 response including IL-4, IL-5, IL-13, and OVA-specific IgE, eotaxin, transforming growth factor-beta1, airway inflammation, expression and metabolites of 12/15-LOX in lung cytosol, lipid peroxidation, and nitric oxide metabolites in the lung, restored the activity and expression of the third subunit of cytochrome-c oxidase in lung mitochondria and bronchial epithelia, respectively, reduced the appearance of cytochrome c in lung cytosol, and also restored mitochondrial ultrastructural changes of bronchial epithelia. In summary, these findings show that Vit-E reduces key mitochondrial dysfunctions and alleviates asthmatic features.
Collapse
Affiliation(s)
- Ulaganathan Mabalirajan
- Molecular Immunogenetics Laboratory, Inst. of Genomics and Integrative Biology, Mall Road, Delhi-110007, India
| | | | | | | | | | | |
Collapse
|
11
|
Yamaki K, Yoshino S. Comparison of inhibitory activities of zinc oxide ultrafine and fine particulates on IgE-induced mast cell activation. Biometals 2009; 22:1031-40. [DOI: 10.1007/s10534-009-9254-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Accepted: 07/03/2009] [Indexed: 10/20/2022]
|
12
|
Complementary and alternative medicine: herbs, phytochemicals and vitamins and their immunologic effects. J Allergy Clin Immunol 2009; 123:283-94; quiz 295-6. [PMID: 19203652 DOI: 10.1016/j.jaci.2008.12.023] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2008] [Revised: 12/18/2008] [Accepted: 12/19/2008] [Indexed: 12/14/2022]
Abstract
Complementary and alternative medicines (CAMs) are used in more than 80% of the world's population and are becoming an increasing component of the US health care system, with more than 70% of the population using CAM at least once and annual spending reaching as much as $34 billion. Since the inception of the National Center for Complementary and Alternative Medicine, there has been an enormous increase in the number of basic science and therapy-based clinical trials exploring CAM. The subspecialty of allergy and immunology represents a particularly fertile area with a large number of CAM therapies that have been shown to affect the immune system. Recent work has uncovered potential biochemical mechanisms involved in the immunomodulatory pathway of many supplemental vitamins (A, D, and E) that appear to affect the differentiation of CD4(+) cell T(H)1 and T(H)2 subsets. Other research has shown that herbs such as resveratrol, quercetin, and magnolol may affect transcription factors such as nuclear factor-kappaB and the signal transducer and activator of transcription/Janus kinase pathways with resultant changes in cytokines and inflammatory mediators. Clinically, there have been hundreds of trials looking at the effect of CAM on asthma, allergic rhinitis, and atopic dermatitis. This article reviews the history of CAM and its use among patients, paying special attention to new research focusing on herbals, phytochemicals, and vitamins and their potential interaction with the immune system.
Collapse
|
13
|
Reiter E, Azzi A, Zingg JM. Enhanced anti-proliferative effects of combinatorial treatment of delta-tocopherol and resveratrol in human HMC-1 cells. Biofactors 2007; 30:67-77. [PMID: 18356579 DOI: 10.1002/biof.5520300201] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The tocopherols (alpha, beta-, gamma-, and delta-tocopherol) and resveratrol are phytochemicals with alleged beneficial effects against atherosclerosis, vascular diseases and different cancers. They both can act as antioxidants, but they also modulate signal transduction and gene expression by non-antioxidant mechanisms. Here we wanted to determine whether the combined treatment of mast cells with the two compounds inhibits cell proliferation more efficiently when compared to individual treatments. Both compounds inhibit HMC-1 mastocytoma cell proliferation and reduce the activity of Protein Kinase B (PKB/Akt) by inhibiting its Ser473-phosphorylation. The combination of 50 microM delta-tocopherol and 50 microM resveratrol inhibits proliferation of HMC-1 cells more efficiently when compared to single treatments. In line with this, PKB Ser473-phosphorylation is inhibited best by delta-tocopherol and resveratrol combinatory treatment. Resveratrol acts more efficiently as an inhibitor of PKB phosphorylation than alpha-, beta-, gamma-tocopherols, whereas delta-tocopherol shows a stronger inhibition possibly as a result of its apoptotic secondary effects. Our data suggest that delta-tocopherol and resveratrol can act additively in reducing cell proliferation and PKB phosphorylation. The combination of phytochemicals with relatively broad specificity on enzymes involved in signal transduction and gene expression may increase their activity in disease prevention by modulating several different molecular targets.
Collapse
Affiliation(s)
- Elke Reiter
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
| | | | | |
Collapse
|