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Idriss M, Younes M, Najem SA, Hodroj MH, Fakhoury R, Rizk S. Gamma-tocotrienol Synergistically Promotes the Anti-proliferative and Pro-apoptotic Effects of Etoposide on Breast Cancer Cell Lines. Curr Mol Pharmacol 2022; 15:980-986. [PMID: 35100963 DOI: 10.2174/1874467215666220131095611] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/05/2021] [Accepted: 11/16/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Breast Cancer is one of the most commonly diagnosed cancers worldwide and a major cause of death among women. Although chemotherapeutic agents remain the keystones in cancer therapy, significant side effects have failed to provide a safe and tolerable treatment for cancer patients. Dietary antioxidant vitamins were extensively investigated over the past years and their relevance in cancer chemotherapy remains to be elucidated. OBJECTIVE In the current study, we aimed to investigate the anti-proliferative and apoptotic effects of combining γ-tocotrienol, a member of the vitamin E family, with the chemotherapeutic drug etoposide in MCF-7 and MDA-MB-231 breast cancer cell lines. METHODS The antiproliferative effect of etoposide combined with γ-tocotrienol was measured using MTS viability reagent. The pro-apoptotic effect was elucidated through Cell Death ELISA and dual Annexin V/PI staining followed by flow cytometric analysis. RESULTS Our results showed that etoposide significantly decreased the cell growth of both cell lines with MDA-MB-231 cells being more sensitive to etoposide treatment than MCF-7. Moreover, the simultaneous treatment of both breast cancer cell lines with low doses of γ-tocotrienol and etoposide induced a synergistic antiproliferative effect (CI<1). Furthermore, the combination therapy significantly increased the percentage of total apoptotic cells in the MDA-MB-231 cell line and the degree of DNA fragmentation as compared to treatment with either compound alone. CONCLUSION In conclusion, our results provide evidence for the profound anti-tumorigenic effect of combined etoposide and γ-tocotrienol in the breast cancer cell lines.
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Affiliation(s)
- Maya Idriss
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos 36, Lebanon
| | - Maria Younes
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos 36, Lebanon
| | - Sonia Abou Najem
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos 36, Lebanon
| | - Mohammad Hassan Hodroj
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos 36, Lebanon
| | - Rajaa Fakhoury
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos 36, Lebanon
| | - Sandra Rizk
- Department of Natural Sciences, School of Arts and Sciences, Lebanese American University, Byblos 36, Lebanon
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Ungurianu A, Zanfirescu A, Nițulescu G, Margină D. Vitamin E beyond Its Antioxidant Label. Antioxidants (Basel) 2021; 10:634. [PMID: 33919211 PMCID: PMC8143145 DOI: 10.3390/antiox10050634] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Revised: 04/14/2021] [Accepted: 04/19/2021] [Indexed: 02/07/2023] Open
Abstract
Vitamin E, comprising tocopherols and tocotrienols, is mainly known as an antioxidant. The aim of this review is to summarize the molecular mechanisms and signaling pathways linked to inflammation and malignancy modulated by its vitamers. Preclinical reports highlighted a myriad of cellular effects like modulating the synthesis of pro-inflammatory molecules and oxidative stress response, inhibiting the NF-κB pathway, regulating cell cycle, and apoptosis. Furthermore, animal-based models have shown that these molecules affect the activity of various enzymes and signaling pathways, such as MAPK, PI3K/Akt/mTOR, JAK/STAT, and NF-κB, acting as the underlying mechanisms of their reported anti-inflammatory, neuroprotective, and anti-cancer effects. In clinical settings, not all of these were proven, with reports varying considerably. Nonetheless, vitamin E was shown to improve redox and inflammatory status in healthy, diabetic, and metabolic syndrome subjects. The anti-cancer effects were inconsistent, with both pro- and anti-malignant being reported. Regarding its neuroprotective properties, several studies have shown protective effects suggesting vitamin E as a potential prevention and therapeutic (as adjuvant) tool. However, source and dosage greatly influence the observed effects, with bioavailability seemingly a key factor in obtaining the preferred outcome. We conclude that this group of molecules presents exciting potential for the prevention and treatment of diseases with an inflammatory, redox, or malignant component.
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Affiliation(s)
- Anca Ungurianu
- Department of Biochemistry, Faculty of Pharmacy, “Carol Davila” University of Medicine and Pharmacy, Traian Vuia 6, 020956 Bucharest, Romania;
| | - Anca Zanfirescu
- Department of Pharmacology and Clinical Pharmacy, Faculty of Pharmacy, “Carol Davila” University of Medicine and Pharmacy, Traian Vuia 6, 020956 Bucharest, Romania;
| | - Georgiana Nițulescu
- Department Pharmaceutical Technology, Faculty of Pharmacy, “Carol Davila” University of Medicine and Pharmacy, Traian Vuia 6, 020956 Bucharest, Romania;
| | - Denisa Margină
- Department of Biochemistry, Faculty of Pharmacy, “Carol Davila” University of Medicine and Pharmacy, Traian Vuia 6, 020956 Bucharest, Romania;
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3
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Therapeutic aspects of AMPK in breast cancer: Progress, challenges, and future directions. Biochim Biophys Acta Rev Cancer 2020; 1874:188379. [PMID: 32439311 DOI: 10.1016/j.bbcan.2020.188379] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Revised: 05/06/2020] [Accepted: 05/10/2020] [Indexed: 12/17/2022]
Abstract
Breast cancer is the most ubiquitous type of neoplasms among women worldwide. Molecular aberrations associated with breast development and progressions have been extensively investigated in recent years. An AMP-activated kinase (AMPK) initially identified as a cellular energy sensor that plays a crucial role in cellular energy homeostasis. Intensive research over the last decade about the molecular mechanisms of AMPK has demonstrated that AMPK mediated diverse biological functions are achieved through phosphorylation and regulation of multiple downstream signaling molecules in normal tissue. Downregulation of AMPK activity or decreased level involved in the promotion of breast tumorigenesis, and thus activation of AMPK found to oppose tumor progression. In this review, we epitomize the recent advances in exploring the tumor suppressor function of AMPK pathways. Besides, we discuss the developments in the area of AMPK activator and its molecular mechanisms for breast cancer treatment.
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Barbosa AM, Martel F. Targeting Glucose Transporters for Breast Cancer Therapy: The Effect of Natural and Synthetic Compounds. Cancers (Basel) 2020; 12:cancers12010154. [PMID: 31936350 PMCID: PMC7016663 DOI: 10.3390/cancers12010154] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 01/06/2020] [Accepted: 01/07/2020] [Indexed: 02/07/2023] Open
Abstract
Reprogramming of cellular energy metabolism is widely accepted to be a cancer hallmark. The deviant energetic metabolism of cancer cells-known as the Warburg effect-consists in much higher rates of glucose uptake and glycolytic oxidation coupled with the production of lactic acid, even in the presence of oxygen. Consequently, cancer cells have higher glucose needs and thus display a higher sensitivity to glucose deprivation-induced death than normal cells. So, inhibitors of glucose uptake are potential therapeutic targets in cancer. Breast cancer is the most commonly diagnosed cancer and a leading cause of cancer death in women worldwide. Overexpression of facilitative glucose transporters (GLUT), mainly GLUT1, in breast cancer cells is firmly established, and the consequences of GLUT inhibition and/or knockout are under investigation. Herein we review the compounds, both of natural and synthetic origin, found to interfere with uptake of glucose by breast cancer cells, and the consequences of interference with that mechanism on breast cancer cell biology. We will also present data where the interaction with GLUT is exploited in order to increase the efficiency or selectivity of anticancer agents, in breast cancer cells.
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Affiliation(s)
- Ana M. Barbosa
- Instituto de Ciências Biomédicas Abel Salazar, University of Porto, 4169-007 Porto, Portugal;
| | - Fátima Martel
- Unit of Biochemistry, Department of Biomedicine, Faculty of Medicine, University of Porto, 4200-319 Porto, Portugal
- Instituto de Investigação e Inovação em Saúde, University of Porto, 4200-135 Porto, Portugal
- Correspondence: ; Tel.: +351-22-042-6654
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5
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Dronamraju V, Ibrahim BA, Briski KP, Sylvester PW. γ-Tocotrienol Suppression of the Warburg Effect Is Mediated by AMPK Activation in Human Breast Cancer Cells. Nutr Cancer 2019; 71:1214-1228. [PMID: 30955359 DOI: 10.1080/01635581.2019.1599969] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Cancer cell metabolism is characterized by aerobic glycolysis or the "Warburg effect". Enhanced Akt signaling is associated with activation of various downstream enzymes involved in the glycolytic process, whereas activation of 5'-AMP-activated kinase (AMPK) acts to terminate energy expending mechanisms and decrease glycolytic enzyme expression. Studies were conducted to determine if the anticancer effects of γ-tocotrienol, are mediated through a suppression in aerobic glycolysis. Results show that treatment with 0-7 μM γ-tocotrienol throughout a 4-day culture period resulted in a dose-responsive increase in AMPK activation, and corresponding decrease in Akt activity in human MCF-7 and MDA-MB-231 breast cancer cells. γ-Tocotrienol treatment was also found to induce a dose-responsive decrease in phosphorylated-Fox03 (inactivated), a transcription factor that acts to inhibit in the levels of glycolytic enzyme, and this decrease was associated with a reduction in glycolytic enzyme levels and activity, as well as glucose consumption in these cells. PCR microarray analysis shows that γ-tocotrienol treatment decreases the expression of genes associate with metabolic signaling and glycolysis in MCF-7 and MDA-MB-231 breast cancer cells. In summary, these findings demonstrate that the anticancer effects of γ-tocotrienol are mediated, at least in part, by a suppression in the Warburg effect.
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Affiliation(s)
| | - Baher A Ibrahim
- College of Pharmacy, University of Louisiana at Monroe , Monroe , Louisiana , USA
| | - Karen P Briski
- College of Pharmacy, University of Louisiana at Monroe , Monroe , Louisiana , USA
| | - Paul W Sylvester
- College of Pharmacy, University of Louisiana at Monroe , Monroe , Louisiana , USA
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6
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Malavolta M, Pierpaoli E, Giacconi R, Basso A, Cardelli M, Piacenza F, Provinciali M. Anti-inflammatory Activity of Tocotrienols in Age-related Pathologies: A SASPected Involvement of Cellular Senescence. Biol Proced Online 2018; 20:22. [PMID: 30479579 PMCID: PMC6247629 DOI: 10.1186/s12575-018-0087-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 11/11/2018] [Indexed: 12/11/2022] Open
Abstract
Tocotrienols (T3) have been shown to represent a very important part of the vitamin E family since they have opened new opportunities to prevent or treat a multitude of age-related chronic diseases. The beneficial effects of T3 include the amelioration of lipid profile, the promotion of Nrf2 mediated cytoprotective activity and the suppression of inflammation. All these effects may be the consequence of the ability of T3 to target multiple pathways. We here propose that these effects may be the result of a single target of T3, namely senescent cells. Indeed, T3 may act by a direct suppression of the senescence-associated secretory phenotype (SASP) produced by senescent cells, mediated by inhibition of NF-kB and mTOR, or may potentially remove the origin of the SASP trough senolysis (selective death of senescent cells). Further studies addressed to investigate the impact of T3 on cellular senescence “in vitro” as well as in experimental models of age-related diseases “in vivo” are clearly encouraged.
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Affiliation(s)
- Marco Malavolta
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Elisa Pierpaoli
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Robertina Giacconi
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Andrea Basso
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Maurizio Cardelli
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Francesco Piacenza
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, via Birarelli 8, 60121 Ancona, Italy
| | - Mauro Provinciali
- Advanced Technology Center for Aging Research, Scientific Technological Area, IRCCS INRCA, via Birarelli 8, 60121 Ancona, Italy
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7
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Montagnani Marelli M, Marzagalli M, Fontana F, Raimondi M, Moretti RM, Limonta P. Anticancer properties of tocotrienols: A review of cellular mechanisms and molecular targets. J Cell Physiol 2018; 234:1147-1164. [PMID: 30066964 DOI: 10.1002/jcp.27075] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 06/28/2018] [Indexed: 12/13/2022]
Abstract
Vitamin E is composed of two groups of compounds: α-, β-, γ-, and δ-tocopherols (TPs), and the corresponding unsaturated tocotrienols (TTs). TTs are found in natural sources such as red palm oil, annatto seeds, and rice bran. In the last decades, TTs (specifically, γ-TT and δ-TT) have gained interest due to their health benefits in chronic diseases, based on their antioxidant, neuroprotective, cholesterol-lowering, anti-inflammatory activities. Several in vitro and in vivo studies pointed out that TTs also exert a significant antitumor activity in a wide range of cancer cells. Specifically, TTs were shown to exert antiproliferative/proapoptotic effects and to reduce the metastatic or angiogenic properties of different cancer cells; moreover, these compounds were reported to specifically target the subpopulation of cancer stem cells, known to be deeply involved in the development of resistance to standard therapies. Interestingly, recent studies pointed out that TTs exert a synergistic antitumor effect on cancer cells when given in combination with either standard antitumor agents (i.e., chemotherapeutics, statins, "targeted" therapies) or natural compounds with anticancer activity (i.e., sesamin, epigallocatechin gallate (EGCG), resveratrol, ferulic acid). Based on these observations, different TT synthetic derivatives and formulations were recently developed and demonstrated to improve TT water solubility and to reduce TT metabolism in cancer cells, thus increasing their biological activity. These promising results, together with the safety of TT administration in healthy subjects, suggest that these compounds might represent a new chemopreventive or anticancer treatment (i.e., in combination with standard therapies) strategy. Clinical trials aimed at confirming this antitumor activity of TTs are needed.
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Affiliation(s)
- Marina Montagnani Marelli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, Italy
| | - Monica Marzagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, Italy
| | - Fabrizio Fontana
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, Italy
| | - Michela Raimondi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, Italy
| | - Roberta Manuela Moretti
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, Italy
| | - Patrizia Limonta
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, Italy
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8
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Tocotrienols: The promising analogues of vitamin E for cancer therapeutics. Pharmacol Res 2018; 130:259-272. [DOI: 10.1016/j.phrs.2018.02.017] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 02/06/2018] [Accepted: 02/12/2018] [Indexed: 12/16/2022]
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9
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Lu Y, Li H, Geng Y. Analysis of the Effects of δ-Tocopherol on RAW264.7 and K562 Cells Based on 1H NMR Metabonomics. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:1039-1046. [PMID: 29313349 DOI: 10.1021/acs.jafc.7b04667] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
δ-Tocopherol (δ-TOH) is a form of vitamin E with higher bioactivity. In this study, we studied the bioactivity of δ-TOH using the IC50 of δ-TOH on RAW264.7 (80 μM) and K562 (110 μM) cells. We compared the differential metabolites from the cell lines with and without δ-TOH treatment by 1H NMR metabonomics analysis. It was found that δ-TOH affected the protein biosynthesis, betaine metabolism, and urea cycle in various ways in both cell lines. Metabolic levels of the cell lines were changed after treatment with δ-TOH as differential metabolites were produced. The betaine level in RAW264.7 cells was reduced significantly, while the l-lactic acid level in K562 cells was significantly enhanced. The metabolic changes might contribute to the switch of the respiration pattern from aerobic respiration to anaerobic respiration in K562 cells. These results are helpful in further understanding the subtoxicity of δ-TOH.
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Affiliation(s)
- Yang Lu
- Key Laboratory of Food Nutrition and Safety of SDNU, Provincial Key Laboratory of Animal Resistant Biology, College of Life Science, Shandong Normal University , Jinan 250014, China
| | - Hui Li
- Key Laboratory of Food Nutrition and Safety of SDNU, Provincial Key Laboratory of Animal Resistant Biology, College of Life Science, Shandong Normal University , Jinan 250014, China
| | - Yue Geng
- Key Laboratory of Food Nutrition and Safety of SDNU, Provincial Key Laboratory of Animal Resistant Biology, College of Life Science, Shandong Normal University , Jinan 250014, China
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10
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Limon-Miro AT, Lopez-Teros V, Astiazaran-Garcia H. Dietary Guidelines for Breast Cancer Patients: A Critical Review. Adv Nutr 2017; 8:613-623. [PMID: 28710147 PMCID: PMC5502868 DOI: 10.3945/an.116.014423] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Current dietary guidelines for breast cancer patients (BCPs) fail to address adequate dietary intakes of macro- and micronutrients that may improve patients' nutritional status. This review includes information from the PubMed and Biomed Central databases over the last 15 y concerning dietary guidelines for BCPs and the potential impact of a personalized, nutrient-specific diet on patients' nutritional status during and after antineoplastic treatment. Results indicated that BCPs should receive a nutritional assessment immediately after diagnosis. In addition, they should be encouraged to pursue and maintain a healthy body weight [body mass index (BMI; in kg/m2) 20-24.9], preserving their lean mass and avoiding an increase in fat mass. Therefore, after nutritional status diagnosis, a conservative energy restriction of 500-1000 kcal/d could be considered in the dietary intervention when appropriate. Based on the reviewed information, we propose a personalized nutrition intervention for BCPs during and after antineoplastic treatment. Specifications in the nutritional therapy should be based on the patients' nutritional status, dietary habits, schedule, activities, and cultural preferences. BCPs' daily energy intake should be distributed as follows: <30% fat/d (mainly monounsaturated and polyunsaturated fatty acids), ∼55% carbohydrates (primarily whole foods such as oats, brown rice, and fruits), and 1.2-1.5 g protein ⋅ kg-1 ⋅ d-1 to avoid sarcopenic obesity. Findings suggest that 5-9 servings/d of fruits (∼150 g/serving) and vegetables (∼75 g/serving) should be encouraged. Garlic and cruciferous vegetables must also be part of the nutrition therapy. Adequate dietary intakes of food-based macro- and micronutrients rich in β-carotene and vitamins A, E, and C can both prevent deterioration in BCPs' nutritional status and improve their overall health and prognosis.
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Affiliation(s)
- Ana Teresa Limon-Miro
- Department of Nutrition, Research Center for Food and Development, Hermosillo, Sonora, Mexico; and
| | - Veronica Lopez-Teros
- Department of Chemical and Biological Sciences, University of Sonora, Hermosillo, Sonora, Mexico
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11
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Abstract
Mitochondria play a key role in ATP generation, redox homeostasis and regulation of apoptosis. Due to the essential role of mitochondria in metabolism and cell survival, targeting mitochondria in cancer cells is considered as an attractive therapeutic strategy. However, metabolic flexibility in cancer cells may enable the upregulation of compensatory pathways, such as glycolysis to support cancer cell survival when mitochondrial metabolism is inhibited. Thus, compounds capable of both targeting mitochondria and inhibiting glycolysis may be particularly useful to overcome such drug-resistant mechanism. This review provides an update on recent development in the field of targeting mitochondria and novel compounds that impact mitochondria, glycolysis or both. Key challenges in this research area and potential solutions are also discussed.
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12
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Torabi S, Yeganehjoo H, Shen CL, Mo H. Peroxisome proliferator-activated receptor γ down-regulation mediates the inhibitory effect of d-δ-tocotrienol on the differentiation of murine 3T3-F442A preadipocytes. Nutr Res 2016; 36:1345-1352. [PMID: 27884413 DOI: 10.1016/j.nutres.2016.11.001] [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: 07/17/2016] [Revised: 10/06/2016] [Accepted: 11/01/2016] [Indexed: 11/26/2022]
Abstract
Tocotrienols accelerate the degradation of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase that catalyzes the biosynthesis of mevalonate; the latter is essential for preadipocyte differentiation. Tocotrienols also down-regulate peroxisome proliferator-activated receptor γ (PPARγ), a key regulator of adipocyte differentiation. We hypothesized that mevalonate deprivation and PPARγ down-regulation mediate d-δ-tocotrienol-induced inhibition of adipocyte differentiation. The objectives of this study were to determine the effect of d-δ-tocotrienol on 3T3-F442A preadipocyte differentiation and the involvement of PPARγ and mevalonate. Murine 3T3-F442A preadipocytes were incubated with d-δ-tocotrienol (2.5-10 μmol/L) for 8 days. AdipoRed assay and Oil Red O staining showed that d-δ-tocotrienol dose-dependently reduced the intracellular triglyceride content. Concomitantly, d-δ-tocotrienol dose-dependently inhibited glucose uptake by 3T3-F442A cells and the expression of GLUT4, HMG CoA reductase, and p-Akt proteins. The effects of d-δ-tocotrienol on intracellular triglyceride content and glucose uptake were attenuated by rosiglitazone, an agonist of PPARγ, but not supplemental mevalonate (100 μmol/L). In contrast, mevalonate, but not rosiglitazone, reversed the effects of lovastatin, a competitive inhibitor of HMG CoA reductase shown to inhibit adipocyte differentiation via mevalonate deprivation. Trypan blue staining revealed no changes in cell viability after a 48-hour incubation of 3T3-F442A cells with d-δ-tocotrienol (0-80 μmol/L), suggesting that the adipogenesis-suppressive activity of d-δ-tocotrienol was independent of cytotoxicity. In conclusion, these findings demonstrate the antiadipogenic effect of d-δ-tocotrienol via PPARγ down-regulation.
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Affiliation(s)
- Sheida Torabi
- Department of Nutrition and Food Sciences, Texas Woman's University, Denton, TX, USA.
| | - Hoda Yeganehjoo
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| | - Chwan-Li Shen
- Department of Pathology, Texas Tech University Health Sciences Center, Lubbock, TX, USA.
| | - Huanbiao Mo
- Department of Nutrition, Byrdine F. Lewis School of Nursing and Health Professions, Georgia State University, Atlanta, GA, USA; Center for Obesity Reversal, Georgia State University, Atlanta, GA, USA.
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13
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Ahmed RA, Alawin OA, Sylvester PW. γ-Tocotrienol reversal of epithelial-to-mesenchymal transition in human breast cancer cells is associated with inhibition of canonical Wnt signalling. Cell Prolif 2016; 49:460-70. [PMID: 27323693 DOI: 10.1111/cpr.12270] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 05/10/2016] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVES Frizzled-7 (FZD7) receptor-dependent activation of the canonical Wnt/β-catenin pathway plays a crucial role in epithelial-to-mesenchymal transition (EMT) and breast cancer metastasis. FZD7 and its co-receptor, low-density lipoprotein receptor-related protein 6 (LRP6), are highly expressed in MDA-MB-231 and T-47D breast cancer cells, and endogenous ligands for FZD7 include Wnt3a and Wnt5a/b. γ-Tocotrienol, a natural isoform of vitamin E, inhibits human breast cancer cell proliferation and EMT. Here, studies have been conducted to investigate the role of the canonical Wnt pathway in mediating inhibitory effects of γ-tocotrienol on EMT in human breast cancer cells. MATERIALS AND METHODS MDA-MB-231, T-47D and MCF-10A cells were maintained in serum-free defined media containing selected doses of γ-tocotrienol. Cell viability was determined using the MTT colorimetric assay, Western blot analysis was used to measure protein expression and the wound-healing assay was employed to study cell mobility and migration. Immunohistochemical fluorescence staining visualized expression and localization of EMT cell markers. RESULTS γ-Tocotrienol was found to induce dose-responsive inhibition of MDA-MB-231 and T-47D cell growth at doses that had no effect on immortalized normal MCF-10A mammary epithelial cells. These growth inhibitory effects were associated with suppression in canonical Wnt signalling, reversal of EMT and significant reduction in breast cancer cell motility. CONCLUSIONS γ-Tocotrienol suppression of metastatic breast cancer cell proliferation and EMT was associated with suppression of the canonical Wnt/β-catenin signalling pathway.
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Affiliation(s)
- R A Ahmed
- School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - O A Alawin
- School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
| | - P W Sylvester
- School of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
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14
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Branco AF, Ferreira A, Simões RF, Magalhães-Novais S, Zehowski C, Cope E, Silva AM, Pereira D, Sardão VA, Cunha-Oliveira T. Ketogenic diets: from cancer to mitochondrial diseases and beyond. Eur J Clin Invest 2016; 46:285-98. [PMID: 26782788 DOI: 10.1111/eci.12591] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/12/2016] [Indexed: 12/13/2022]
Abstract
BACKGROUND The employment of dietary strategies such as ketogenic diets, which force cells to alter their energy source, has shown efficacy in the treatment of several diseases. Ketogenic diets are composed of high fat, moderate protein and low carbohydrates, which favour mitochondrial respiration rather than glycolysis for energy metabolism. DESIGN This review focuses on how oncological, neurological and mitochondrial disorders have been targeted by ketogenic diets, their metabolic effects, and the possible mechanisms of action on mitochondrial energy homeostasis. The beneficial and adverse effects of the ketogenic diets are also highlighted. RESULTS AND CONCLUSIONS Although the full mechanism by which ketogenic diets improve oncological and neurological conditions still remains to be elucidated, their clinical efficacy has attracted many new followers, and ketogenic diets can be a good option as a co-adjuvant therapy, depending on the situation and the extent of the disease.
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Affiliation(s)
- Ana F Branco
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - André Ferreira
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Rui F Simões
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | | | - Cheryl Zehowski
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA
| | - Elisabeth Cope
- Department of Applied Medical Sciences, University of Southern Maine, Portland, ME, USA
| | - Ana Marta Silva
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Daniela Pereira
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Vilma A Sardão
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Teresa Cunha-Oliveira
- CNC - Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
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