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Azzi A, Atkinson J, Ozer NK, Manor D, Wallert M, Galli F. Vitamin E discussion forum position paper on the revision of the nomenclature of vitamin E. Free Radic Biol Med 2023; 207:178-180. [PMID: 37463635 PMCID: PMC10681751 DOI: 10.1016/j.freeradbiomed.2023.06.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 06/22/2023] [Accepted: 06/26/2023] [Indexed: 07/20/2023]
Abstract
This position paper opens a discussion forum of this Journal dedicated to a scientific debate on Vitamin E nomenclature. With this article we provide the scientific and medical communities with what we consider relevant information in favor of revising the nomenclature of vitamin E. To our knowledge, only RRR-α-tocopherol has been medically used to protect against a deficiency disease in humans, and therefore, it would be appropriate to restrict the term vitamin to this molecule. The direct demonstration of a vitamin function to other tocochromanols (including other tocopherols, tocotrienols and eventually tocomonoenols), has not yet been scientifically shown. In fact, the medical prescription of a molecule against the deficiency disease only because it has been included in the "Vitamin E family", but not tested as vitamin E, could lead to ineffective therapy and potentially dangerous consequences for patients. The idea of this revision launched during the recent 3rd Satellite Symposium on Vitamin E of the 2022 SFRR-Europe meeting, offers a open platform of discussion for the scientists involved in vitamin E research and scientific societies interested to this subject.
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Affiliation(s)
- Angelo Azzi
- School of Graduate Biomedical Pharmacology and Drug Development Program, Tufts University, Boston, MA, USA.
| | - Jeffrey Atkinson
- Department of Chemistry and Centre for Biotechnology, Brock University, St. Catharines, L2S3A1, Ontario, Canada
| | - Nesrin Kartal Ozer
- Department of Biochemistry, Faculty of Medicine, Uskudar University, 34662, Uskudar, Istanbul, Turkey
| | - Danny Manor
- Department of Nutrition, School of Medicine, Case Western Reserve University, 44106, Cleveland, OH, USA
| | - Maria Wallert
- Biochemistry and Physiology of Nutrition, Institute of Nutritional Science, Friedrich Schiller University, Jena, Germany
| | - Francesco Galli
- Human Nutrition and Nutrigenomics Lab, Dept of Pharmaceutical Sciences, University of Perugia, 06122, Perugia, Italy.
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Fontana F, Marzagalli M, Raimondi M, Zuco V, Zaffaroni N, Limonta P. δ-Tocotrienol sensitizes and re-sensitizes ovarian cancer cells to cisplatin via induction of G1 phase cell cycle arrest and ROS/MAPK-mediated apoptosis. Cell Prolif 2021; 54:e13111. [PMID: 34520051 PMCID: PMC8560608 DOI: 10.1111/cpr.13111] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 07/20/2021] [Accepted: 07/30/2021] [Indexed: 12/12/2022] Open
Abstract
OBJECTIVES Among gynaecologic malignancies, ovarian cancer (OC) represents the leading cause of death for women worldwide. Current OC treatment involves cytoreductive surgery followed by platinum-based chemotherapy, which is associated with severe side effects and development of drug resistance. Therefore, new therapeutic strategies are urgently needed. Herein, we evaluated the anti-tumour effects of Vitamin E-derived δ-tocotrienol (δ-TT) in two human OC cell lines, IGROV-1 and SKOV-3 cells. MATERIALS AND METHODS MTT and Trypan blue exclusion assays were used to assess δ-TT cytotoxicity, alone or in combination with other molecules. δ-TT effects on cell cycle, apoptosis, ROS generation and MAPK phosphorylation were investigated by flow cytometry, Western blot and immunofluorescence analyses. The synergism between δ-TT and chemotherapy was evaluated by isobologram analysis. RESULTS We demonstrated that δ-TT could induce cell cycle block at G1-S phase and mitochondrial apoptosis in OC cell lines. In particular, we found that the proapoptotic activity of δ-TT correlated with mitochondrial ROS production and subsequent JNK and p38 activation. Finally, we observed that the compound was able to synergize with cisplatin, not only enhancing its cytotoxicity in IGROV-1 and SKOV-3 cells but also re-sensitizing IGROV-1/Pt1 cell line to its anti-tumour effects. CONCLUSIONS δ-TT triggers G1 phase cell cycle arrest and ROS/MAPK-mediated apoptosis in OC cells and sensitizes them to platinum treatment, thus representing an interesting option for novel chemopreventive/therapeutic strategies for OC.
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Affiliation(s)
- Fabrizio Fontana
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Monica Marzagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Michela Raimondi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Valentina Zuco
- Department of Applied Research and Technological Development, Molecular Pharmacology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Nadia Zaffaroni
- Department of Applied Research and Technological Development, Molecular Pharmacology Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
| | - Patrizia Limonta
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
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3
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Shen J, Yang T, Tang Y, Guo T, Guo T, Hu T, Luo F, Lin Q. δ-Tocotrienol induces apoptosis and inhibits proliferation of nasopharyngeal carcinoma cells. Food Funct 2021; 12:6374-6388. [PMID: 34056642 DOI: 10.1039/d1fo00461a] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Nasopharyngeal carcinoma has a notably high incidence rate in Southern China, Southeast Asia, North Africa, Middle East, and the Arctic. δ-Tocotrienol is abundant in cereal and has some health benefits. In our recent study, we showed that δ-tocotrienol exerted anti-inflammatory effects in murine macrophages in vitro. The aim of this study was to further investigate the chemopreventive effects of δ-tocotrienol on human CNE1 cells. We showed that δ-tocotrienol induced apoptosis and cell cycle arrest at G0/G1 and M phases in nasopharyngeal carcinoma cells. Microarray analysis revealed that after CNE1 cells were treated with δ-tocotrienol, 169 genes were up-regulated and 167 down-regulated. ERK1/2 was shown to play a vital role in cell cycle arrest by gene chips. The results suggest that δ-tocotrienol induces cell cycle arrest in CNE1 cells via the p16/CDK4/cyclin D1 signaling pathway. Western blots showed that CNE1 apoptosis was related to dysregulated expression of Bax-2 and Bcl-2. Furthermore, caspase-3, -8, -9 up-regulation was related to the apoptotic effect of δ-tocotrienol; therefore, δ-tocotrienol triggers apoptosis in CNE1 cells through caspase-3 signaling. δ-Tocotrienol may potentially be developed as an anti-cancer agent in the management of nasopharyngeal carcinoma.
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Affiliation(s)
- Junjun Shen
- Laboratory of Molecular Nutrition, College of Food Science and Engineering, National Engineering Laboratory for Deep Processing of Rice and Byproducts, Central South University of Forestry and Technology, Changsha, Hunan 410004, China.
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4
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Raimondi M, Fontana F, Marzagalli M, Audano M, Beretta G, Procacci P, Sartori P, Mitro N, Limonta P. Ca 2+ overload- and ROS-associated mitochondrial dysfunction contributes to δ-tocotrienol-mediated paraptosis in melanoma cells. Apoptosis 2021; 26:277-292. [PMID: 33811561 PMCID: PMC8197726 DOI: 10.1007/s10495-021-01668-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/16/2021] [Indexed: 12/13/2022]
Abstract
Melanoma is an aggressive tumor with still poor therapy outcomes. δ-tocotrienol (δ-TT) is a vitamin E derivative displaying potent anti-cancer properties. Previously, we demonstrated that δ-TT triggers apoptosis in human melanoma cells. Here, we investigated whether it might also activate paraptosis, a non-canonical programmed cell death. In accordance with the main paraptotic features, δ-TT was shown to promote cytoplasmic vacuolization, associated with endoplasmic reticulum/mitochondrial dilation and protein synthesis, as well as MAPK activation in A375 and BLM cell lines. Moreover, treated cells exhibited a significant reduced expression of OXPHOS complex I and a marked decrease in oxygen consumption and mitochondrial membrane potential, culminating in decreased ATP synthesis and AMPK phosphorylation. This mitochondrial dysfunction resulted in ROS overproduction, found to be responsible for paraptosis induction. Additionally, δ-TT caused Ca2+ homeostasis disruption, with endoplasmic reticulum-derived ions accumulating in mitochondria and activating the paraptotic signaling. Interestingly, by using both IP3R and VDAC inhibitors, a close cause-effect relationship between mitochondrial Ca2+ overload and ROS generation was evidenced. Collectively, these results provide novel insights into δ-TT anti-melanoma activity, highlighting its ability to induce mitochondrial dysfunction-mediated paraptosis. δ-tocotrienol induces paraptotic cell death in human melanoma cells, causing endoplasmic reticulum dilation and mitochondrial swelling. These alterations induce an impairment of mitochondrial function, ROS production and calcium overload.
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Affiliation(s)
- Michela Raimondi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Fabrizio Fontana
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Monica Marzagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Matteo Audano
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Giangiacomo Beretta
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy
| | - Patrizia Procacci
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
| | - Patrizia Sartori
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy
| | - Nico Mitro
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy
| | - Patrizia Limonta
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
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de Oliveira VA, Pereira IC, Nogueira TR, Martins JA, Péres-Rodrigues G, de Jesus e Silva de Almendra B, Silva VC, Júnior DD, Leal FL, de Castro e Sousa JM, da Silva FC, de Carvalho Melo Cavalcanti AA, de Azevedo Paiva A. The Role of Vitamin E in Breast Cancer Treatment and Prevention: Current Perspectives. CURRENT NUTRITION & FOOD SCIENCE 2021. [DOI: 10.2174/1573401316999200614164711] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:
Regarding the multifactorial etiology of breast cancer, food choices, as well
as dietary intake, are the main modified factors in cancer prevention. In this sense, understanding
molecular pathways involved in breast cancer proliferation can help determine the mechanisms of
action of organic compounds such as antioxidant vitamins that are known to protect against cancer.
Objective:
Assess the mechanism of action of vitamin E in breast cancer modulation, with emphasis
on important markers of tumor development.
Methods:
It is a systematic review carried out in PubMed and Web of Science databases, from the
last 5 years, in Portuguese, English and Spanish. The following terms were selected according to The
Medical Subject Headings (MeSH): “breast cancer” OR “breast neoplasms”, “tocopherol” OR
“tocotrienols” OR “vitamin E”, as equated terms.
Results:
A total of 595 articles were found and 25 were selected according to inclusion criteria.
Vitamin E has been related to suppression/overexpression of important tumorigenic pathways,
mainly associated with proliferation, energy metabolism, chemosensitivity and invasion/metastasis.
Clinical studies of vitamin E supplementation are needed to assess the dose/response effect on breast
cancer patients.
Conclusion:
The safety of vitamin E supplementation is still controversial due to current studies design
available. However, when vitamin E is supplemented, the dose and therapeutic regimen must be
carefully decided, including the route of administration and breast cancer subtypes to enhance
desired effects and minimize unwanted side effects.
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Affiliation(s)
- Victor A. de Oliveira
- Department of Nutrition, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | - Irislene C. Pereira
- Postgraduate Program in Food and Nutrition, Department of Nutrition, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | - Thaís R. Nogueira
- Postgraduate Program in Food and Nutrition, Department of Nutrition, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | - Jorddam A. Martins
- Postgraduate Program in Food and Nutrition, Department of Nutrition, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | | | | | - Vladimir C. Silva
- Department of Biochemistry and Pharmacology, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | - Dalton D. Júnior
- Department of Biochemistry and Pharmacology, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | - Francisco L.T. Leal
- Department of Biophysics and Physiology, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | - Joáo M. de Castro e Sousa
- Department of Biochemistry and Pharmacology, Federal University of Piaui, UFPI, Piaui State, Teresina, Brazil
| | - Felipe C.C. da Silva
- Department of Biology, Federal University of Piaui, UFPI, Piaui State, Picos, Brazil
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Fontana F, Raimondi M, Marzagalli M, Audano M, Beretta G, Procacci P, Sartori P, Mitro N, Limonta P. Mitochondrial functional and structural impairment is involved in the antitumor activity of δ-tocotrienol in prostate cancer cells. Free Radic Biol Med 2020; 160:376-390. [PMID: 32738396 DOI: 10.1016/j.freeradbiomed.2020.07.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 06/19/2020] [Accepted: 07/08/2020] [Indexed: 02/07/2023]
Abstract
The therapeutic options for castration-resistant prostate cancer (CRPC) are still limited. Natural bioactive compounds were shown to possess pro-death properties in different tumors. We previously reported that δ-tocotrienol (δ-TT) induces apoptosis, paraptosis and autophagy in CRPC cells. Here, we investigated whether δ-TT might exert its activity by impairing mitochondrial functions. We demonstrated that, in PC3 and DU145 cells, δ-TT impairs mitochondrial respiration and structural dynamics. In both cell lines, δ-TT triggers mitochondrial Ca2+ and ROS overload. In PC3 cells, both Ca2+ and ROS mediate the δ-TT-related anticancer activities (decrease of cell viability, apoptosis, paraptosis, autophagy and mitophagy). As expected, in autophagy-defective DU145 cells, Ca2+ overload was involved in δ-TT-induced pro-death effects but not in autophagy and mitophagy. In this cell line, we also demonstrated that ROS overload is not involved in the anticancer activities of δ-TT, supporting a low susceptibility of these cells to ROS-related oxidative stress. Taken together, these data demonstrate that, in CRPC cells, δ-TT triggers cell death by inducing mitochondrial functional and structural impairments, providing novel mechanistic insights in its antitumor activity.
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Affiliation(s)
- Fabrizio Fontana
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
| | - Michela Raimondi
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
| | - Monica Marzagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
| | - Matteo Audano
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
| | - Giangiacomo Beretta
- Department of Environmental Science and Policy, Università degli Studi di Milano, Milan, Italy.
| | - Patrizia Procacci
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.
| | - Patrizia Sartori
- Department of Biomedical Sciences for Health, Università degli Studi di Milano, Milan, Italy.
| | - Nico Mitro
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
| | - Patrizia Limonta
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milan, Italy.
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7
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Fontana F, Raimondi M, Marzagalli M, Moretti RM, Marelli MM, Limonta P. Tocotrienols and Cancer: From the State of the Art to Promising Novel Patents. Recent Pat Anticancer Drug Discov 2019; 14:5-18. [PMID: 30652648 DOI: 10.2174/1574892814666190116111827] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/04/2019] [Accepted: 01/04/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Tocotrienols (TTs) are vitamin E derivatives naturally occurring in several plants and vegetable oils. Like Tocopherols (TPs), they comprise four isoforms, α, β, γ and δ, but unlike TPs, they present an unsaturated isoprenoid chain. Recent studies indicate that TTs provide important health benefits, including neuroprotective, anti-inflammatory, anti-oxidant, cholesterol lowering and immunomodulatory effects. Moreover, they have been found to possess unique anti-cancer properties. OBJECTIVE The purpose of this review is to present an overview of the state of the art of TTs role in cancer prevention and treatment, as well as to describe recent patents proposing new methods for TTs isolation, chemical modification and use in cancer prevention and/or therapy. METHODS Recent literature and patents focusing on TTs anti-cancer applications have been identified and reviewed, with special regard to their scientific impact and novelty. RESULTS TTs have demonstrated significant anti-cancer activity in multiple tumor types, both in vitro and in vivo. Furthermore, they have shown synergistic effects when given in combination with standard anti-cancer agents or other anti-tumor natural compounds. Finally, new purification processes and transgenic sources have been designed in order to improve TTs production, and novel TTs formulations and synthetic derivatives have been developed to enhance their solubility and bioavailability. CONCLUSION The promising anti-cancer effects shown by TTs in several preclinical studies may open new opportunities for therapeutic interventions in different tumors. Thus, clinical trials aimed at confirming TTs chemopreventive and tumor-suppressing activity, particularly in combination with standard therapies, are urgently needed.
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Affiliation(s)
- Fabrizio Fontana
- Department of Excellence, Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Michela Raimondi
- Department of Excellence, Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Monica Marzagalli
- Department of Excellence, Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Roberta M Moretti
- Department of Excellence, Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Marina Montagnani Marelli
- Department of Excellence, Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
| | - Patrizia Limonta
- Department of Excellence, Department of Pharmacological and Biomolecular Sciences, University of Milan, Milan, Italy
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γ-Tocotrienol inhibits oxidative phosphorylation and triggers apoptosis by inhibiting mitochondrial complex I subunit NDUFB8 and complex II subunit SDHB. Toxicology 2019; 417:42-53. [PMID: 30769052 DOI: 10.1016/j.tox.2019.01.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 01/23/2019] [Accepted: 01/29/2019] [Indexed: 12/19/2022]
Abstract
Tocotrienols (T3s) are a subgroup of vitamin E and they have been widely tested to inhibit cell growth in various tumor types. Previous studies have shown that T3s inhibit cancer cell growth by targeting multiple signaling transduction and cellular processes. However, the role of T3s in the regulation of cellular bioenergetic processes remains unclear. In this study, we found that γ-T3 interacts with mitochondrial electron transfer chain NDUFB8 (a subunit of complex I) and SDHB (a subunit of complex II) and inhibits oxidative phosphorylation (OXPHOS), and triggers the production of reactive oxygen species (ROS). In addition, we observed that γ-T3 upregulates the glycolytic capacity in cells, but it did not compensate for cellular ATP generation and decreased the ATP levels in cells. Furthermore, we performed western blots and RT-PCR to measure the mRNA and protein levels of mitochondrial electron transfer chain (ETC) proteins and complex V (ATP synthase), where the results indicated that γ-T3 specifically inhibited the levels of NDUFB8 and SDHB, whereas it had little effect on UQCRC2 (a subunit of complex III), COX4I1 (a subunit of complex IV), and ATP5F1A (a subunit of complex V). The inhibition of NDUFB8 and SDHB by γ-T3 led to the overproduction of ROS and the depletion of ATP, which may be responsible for inducing apoptosis in cancer cells. Our results suggest that mitochondrial respiration may be an effective target for anticancer treatments based on γ-T3.
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Tham SY, Loh HS, Mai CW, Fu JY. Tocotrienols Modulate a Life or Death Decision in Cancers. Int J Mol Sci 2019; 20:E372. [PMID: 30654580 PMCID: PMC6359475 DOI: 10.3390/ijms20020372] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/05/2019] [Accepted: 01/10/2019] [Indexed: 02/06/2023] Open
Abstract
Malignancy often arises from sophisticated defects in the intricate molecular mechanisms of cells, rendering a complicated molecular ground to effectively target cancers. Resistance toward cell death and enhancement of cell survival are the common adaptations in cancer due to its infinite proliferative capacity. Existing cancer treatment strategies that target a single molecular pathway or cancer hallmark fail to fully resolve the problem. Hence, multitargeted anticancer agents that can concurrently target cell death and survival pathways are seen as a promising alternative to treat cancer. Tocotrienols, a minor constituent of the vitamin E family that have previously been reported to induce various cell death mechanisms and target several key survival pathways, could be an effective anticancer agent. This review puts forward the potential application of tocotrienols as an anticancer treatment from a perspective of influencing the life or death decision of cancer cells. The cell death mechanisms elicited by tocotrienols, particularly apoptosis and autophagy, are highlighted. The influences of several cell survival signaling pathways in shaping cancer cell death, particularly NF-κB, PI3K/Akt, MAPK, and Wnt, are also reviewed. This review may stimulate further mechanistic researches and foster clinical applications of tocotrienols via rational drug designs.
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Affiliation(s)
- Shiau-Ying Tham
- School of Biosciences, Faculty of Science and Engineering, University of Nottingham Malaysia Campus, Jalan Broga, Semenyih 43500, Selangor, Malaysia.
| | - Hwei-San Loh
- School of Biosciences, Faculty of Science and Engineering, University of Nottingham Malaysia Campus, Jalan Broga, Semenyih 43500, Selangor, Malaysia.
- Biotechnology Research Centre, University of Nottingham Malaysia Campus, Jalan Broga, Semenyih 43500, Selangor, Malaysia.
| | - Chun-Wai Mai
- School of Pharmacy, International Medical University, Bukit Jalil, Kuala Lumpur 57000, Malaysia.
- Centre for Cancer and Stem Cell Research, Institute for Research, Development and Innovation, International Medical University, Bukit Jalil, Kuala Lumpur 57000, Malaysia.
| | - Ju-Yen Fu
- Nutrition Unit, Product Development and Advisory Services Division, Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, Kajang 43000, Selangor, Malaysia.
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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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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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12
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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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13
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Piroddi M, Albini A, Fabiani R, Giovannelli L, Luceri C, Natella F, Rosignoli P, Rossi T, Taticchi A, Servili M, Galli F. Nutrigenomics of extra-virgin olive oil: A review. Biofactors 2017; 43:17-41. [PMID: 27580701 DOI: 10.1002/biof.1318] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2016] [Revised: 07/08/2016] [Accepted: 07/08/2016] [Indexed: 12/11/2022]
Abstract
Nutrigenomics data on the functional components of olive oil are still sparse, but rapidly increasing. Olive oil is the main source of fat and health-promoting component of the Mediterranean diet. Positive effects have been observed on genes involved in the pathobiology of most prevalent age- and lifestyle-related human conditions, such as cancer, cardiovascular disease and neurodegeneration. Other effects on health-promoting genes have been identified for bioactive components of olives and olive leafs. Omics technologies are offering unique opportunities to identify nutritional and health biomarkers associated with these gene responses, the use of which in personalized and even predictive protocols of investigation, is a main breakthrough in modern medicine and nutrition. Gene regulation properties of the functional components of olive oil, such as oleic acid, biophenols and vitamin E, point to a role for these molecules as natural homeostatic and even hormetic factors with applications as prevention agents in conditions of premature and pathologic aging. Therapeutic applications can be foreseen in conditions of chronic inflammation, and particularly in cancer, which will be discussed in detail in this review paper as major clinical target of nutritional interventions with olive oil and its functional components. © 2016 BioFactors, 43(1):17-41, 2017.
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Affiliation(s)
- Marta Piroddi
- Department of Pharmaceutical Sciences, Nutrition and Clinical Biochemistry Lab, University of Perugia, Italy
| | - Adriana Albini
- IRCCS MultiMedica, Scientific and Technology Pole, Milan, Italy
| | - Roberto Fabiani
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Italy
| | - Lisa Giovannelli
- NEUROFARBA - Section of Phamacology and Toxicology, University of Firenze, Italy
| | - Cristina Luceri
- NEUROFARBA - Section of Phamacology and Toxicology, University of Firenze, Italy
| | - Fausta Natella
- CREA-NUT, Consiglio per La Ricerca in Agricoltura E L'Analisi Dell'Economia Agraria, Food and Nutrition Research Centre, via Ardeatina 546, 00178, Roma, Italy
| | - Patrizia Rosignoli
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Italy
| | - Teresa Rossi
- Research and Statistics, Department, IRCCS "Tecnologie Avanzate E Modelli Assistenziali in Oncologia", Laboratory of Translational Research, Arcispedale S. Maria Nuova-IRCCS, Reggio Emilia, Italy
| | - Agnese Taticchi
- Department of Agricultural Food and Environmental Sciences, University of Perugia, Italy
| | - Maurizio Servili
- Department of Agricultural Food and Environmental Sciences, University of Perugia, Italy
| | - Francesco Galli
- Department of Pharmaceutical Sciences, Nutrition and Clinical Biochemistry Lab, University of Perugia, Italy
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14
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Montagnani Marelli M, Marzagalli M, Moretti RM, Beretta G, Casati L, Comitato R, Gravina GL, Festuccia C, Limonta P. Vitamin E δ-tocotrienol triggers endoplasmic reticulum stress-mediated apoptosis in human melanoma cells. Sci Rep 2016; 6:30502. [PMID: 27461002 PMCID: PMC4996065 DOI: 10.1038/srep30502] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 07/06/2016] [Indexed: 12/13/2022] Open
Abstract
Malignant melanoma is the leading cause of death from skin cancer. Drug toxicity and resistance represent a serious challange for melanoma treatments. Evidence demonstrates that natural compounds may play a crucial role in cancer prevention, growth and progression. Vitamin E tocotrienols (TT) were shown to possess antitumor activity. Here, we analyzed the effects of δ-TT on melanoma cell growth and the involvement of the endoplasmic reticulum (ER) stress in this activity. The experiments were performed on human melanoma cell lines, BLM and A375. δ-TT exerted a significant proapoptotic effect on both cell lines, involving the intrinsic apoptosis pathway; importantly, this compound did not affect the viability of normal human melanocytes. In melanoma cells, δ-TT exerted its antitumor effect through activation of the PERK/p-eIF2α/ATF4/CHOP, IRE1α and caspase-4 ER stress-related branches. Salubrinal, an inhibitor of the ER stress, counteracted the cytotoxic activity of δ-TT. In vivo experiments performed in nude mice bearing A375 xenografts evidenced that δ-TT reduces tumor volume and tumor mass; importantly, tumor progression was significantly delayed by δ-TT treatment. In conclusion, δ-TT exerts a proapoptotic activity on melanoma cells, through activation of the ER stress-related pathways. δ-TT might represent an effective option for novel chemopreventive/therapeutic strategies for melanoma.
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Affiliation(s)
- Marina Montagnani Marelli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, 20133, Italy
| | - Monica Marzagalli
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, 20133, Italy
| | - Roberta M. Moretti
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, 20133, Italy
| | - Giangiacomo Beretta
- Department of Pharmaceutical Sciences, Università degli Studi di Milano, Milano, 20133, Italy
| | - Lavinia Casati
- Department of Medical Biotechnologies and Translational Medicine, Università degli Studi di Milano, Milano, 20129, Italy
| | - Raffaella Comitato
- Council for Agricultural Research and Economics, Food and Nutrition Research Centre, Roma, 00178, Italy
| | - Giovanni L. Gravina
- Department of Applied and Biotechnological Clinical Sciences, Università degli Studi dell’Aquila, L’Aquila, 67100, Italy
| | - Claudio Festuccia
- Department of Applied and Biotechnological Clinical Sciences, Università degli Studi dell’Aquila, L’Aquila, 67100, Italy
| | - Patrizia Limonta
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Milano, 20133, Italy
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15
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Do MH, Kim SN, Seo SY, Yeo EJ, Kim SY. δ-Tocopherol prevents methylglyoxal-induced apoptosis by reducing ROS generation and inhibiting apoptotic signaling cascades in human umbilical vein endothelial cells. Food Funct 2016; 6:1568-77. [PMID: 25832198 DOI: 10.1039/c4fo01110d] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Methylglyoxal (MGO) is a highly reactive metabolite of glucose, which is known to cause damage and induce apoptosis in endothelial cells. Endothelial cell damage is implicated in the progression of diabetes-associated complications and atherosclerosis. Nuts are high in vitamin E. Consumption of nuts has been recommended for the prevention of cardiovascular disease. However, different nuts contain different forms of vitamin E, which can have different effects on endothelial cells. In this work, we investigated the protective effect of different isoforms of vitamin E on MGO-induced apoptosis in human umbilical vein endothelial cells (HUVECs). Among all forms of vitamin E, δ-tocopherol showed the highest effect on apoptosis of HUVECs. We also compared the anti-apoptotic activity of δ-tocopherol with that of α-tocopherol in MGO-treated HUVECs. Pretreatment with α- or δ-tocopherol significantly inhibited MGO-induced changes in cell morphology, cell death, and production of intracellular reactive oxygen species. δ-Tocopherol prevented MGO-induced apoptosis in HUVECs by increasing Bcl-2 expression and decreasing Bax expression. Interestingly, α-tocopherol also inhibited these factors but to a lesser extent than δ-tocopherol. MGO was found to activate mitogen-activated protein kinases (MAPKs). Compared to pretreatment with α-tocopherol, pretreatment with δ-tocopherol more strongly inhibited the activation of MAPKs, such as JNK and ERK1/2. These findings suggest that δ-tocopherol may be a more effective regulator of MGO-induced apoptosis than α-tocopherol.
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Affiliation(s)
- Moon ho Do
- College of Pharmacy, Gachon University, Incheon, Republic of Korea.
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16
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Drotleff AM, Büsing A, Willenberg I, Empl MT, Steinberg P, Ternes W. HPLC Separation of Vitamin E and Its Oxidation Products and Effects of Oxidized Tocotrienols on the Viability of MCF-7 Breast Cancer Cells in Vitro. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:8930-8939. [PMID: 26405759 DOI: 10.1021/acs.jafc.5b04388] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Tocotrienols, a vitamin E subgroup, exert potent anticancer effects, but easily degrade due to oxidation. Eight vitamin E reference compounds, α-, β-, γ-, or δ-tocopherols or -tocotrienols, were thermally oxidized in n-hexane. The corresponding predominantly dimeric oxidation products were separated from the parent compounds by diol-modified normal-phase HPLC-UV and characterized by mass spectroscopy. The composition of test compounds, that is, α-tocotrienol, γ-tocotrienol, or palm tocotrienol-rich fraction (TRF), before and after thermal oxidation was determined by HPLC-DAD, and MCF-7 cells were treated with both nonoxidized and oxidized test compounds for 72 h. Whereas all nonoxidized test compounds (0-100 μM) led to dose-dependent decreases in cell viability, equimolar oxidized α-tocotrienol had a weaker effect, and oxidized TRF had no such effect. However, the IC50 value of oxidized γ-tocotrienol was lower (85 μM) than that of nonoxidized γ-tocotrienol (134 μM), thereby suggesting that γ-tocotrienol oxidation products are able to reduce tumor cell viability in vitro.
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Affiliation(s)
- Astrid M Drotleff
- Department of Analytical Chemistry and ‡Department of Food Toxicology, Center for Food Sciences, Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover Foundation , Bischofsholer Damm 15, D-30173 Hannover, Germany
| | - Anne Büsing
- Department of Analytical Chemistry and ‡Department of Food Toxicology, Center for Food Sciences, Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover Foundation , Bischofsholer Damm 15, D-30173 Hannover, Germany
| | - Ina Willenberg
- Department of Analytical Chemistry and ‡Department of Food Toxicology, Center for Food Sciences, Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover Foundation , Bischofsholer Damm 15, D-30173 Hannover, Germany
| | - Michael T Empl
- Department of Analytical Chemistry and ‡Department of Food Toxicology, Center for Food Sciences, Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover Foundation , Bischofsholer Damm 15, D-30173 Hannover, Germany
| | - Pablo Steinberg
- Department of Analytical Chemistry and ‡Department of Food Toxicology, Center for Food Sciences, Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover Foundation , Bischofsholer Damm 15, D-30173 Hannover, Germany
| | - Waldemar Ternes
- Department of Analytical Chemistry and ‡Department of Food Toxicology, Center for Food Sciences, Institute for Food Toxicology and Analytical Chemistry, University of Veterinary Medicine Hannover Foundation , Bischofsholer Damm 15, D-30173 Hannover, Germany
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17
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Wang C, Husain K, Zhang A, Centeno BA, Chen DT, Tong Z, Sebti SM, Malafa MP. EGR-1/Bax pathway plays a role in vitamin E δ-tocotrienol-induced apoptosis in pancreatic cancer cells. J Nutr Biochem 2015; 26:797-807. [PMID: 25997867 DOI: 10.1016/j.jnutbio.2015.02.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 02/10/2015] [Accepted: 02/11/2015] [Indexed: 12/13/2022]
Abstract
The anticancer activity of δ-tocotrienol, a bioactive vitamin E present in whole grain cereals, annatto beans and palm fruit, is strongly dependent on its effect on the induction of apoptosis. δ-Tocotrienol-induced apoptosis is associated with consistent induction in the expression of the proapoptotic protein Bcl-2-associated X protein (Bax). The molecular mechanism by which δ-tocotrienol regulates Bax expression is unknown. We carried out a DNA microarray study that identified δ-tocotrienol induction of the zinc finger transcription factor EGR-1 in pancreatic cancer cells. Here, we provide evidence linking δ-tocotrienol-induced apoptosis in pancreatic cancer cells to EGR-1 regulation of Bax expression. Forced expression of EGR-1 induces Bax expression and apoptosis in pancreatic cancer cells. In contrast, knockdown of δ-tocotrienol-induced EGR-1 by small interfering RNA attenuated δ-tocotrienol-induced Bax expression and reduced δ-tocotrienol-induced apoptosis. Further analyses showed that de novo protein synthesis was not required for δ-tocotrienol-induced EGR-1 expression, suggesting a direct effect of δ-tocotrienol on EGR-1 expression. Furthermore, a chromatin immunoprecipitation assay demonstrated that EGR-1 binds to the Bax gene promoter. Finally, δ-tocotrienol treatment induced Bax expression and activated EGR-1 in the pancreatic neoplastic cells of the PDX-Cre Kras genetically engineered model of pancreatic cancer. Our study provides the first evidence for EGR-1 as a direct target of vitamin E δ-tocotrienol, suggesting that EGR-1 may act as a proapoptotic factor in pancreatic cancer cells via induction of Bax.
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Affiliation(s)
- Chen Wang
- Department of Gastrointestinal Oncology, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL; Department of Breast Oncology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Kazim Husain
- Department of Gastrointestinal Oncology, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL
| | - Anying Zhang
- Department of Gastrointestinal Oncology, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL; Department of School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China
| | - Barbara A Centeno
- Department of Pathology, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL
| | - Dung-Tsa Chen
- Department of Biostatistics, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL
| | - Zhongsheng Tong
- Department of Breast Oncology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Säid M Sebti
- Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL
| | - Mokenge P Malafa
- Department of Gastrointestinal Oncology, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL; Department of Drug Discovery, H. Lee Moffitt Cancer Center and Research Institute, 12902 Magnolia Drive, Tampa, FL.
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18
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Sylvester PW, Akl MR, Malaviya A, Parajuli P, Ananthula S, Tiwari RV, Ayoub NM. Potential role of tocotrienols in the treatment and prevention of breast cancer. Biofactors 2014; 40:49-58. [PMID: 23804535 DOI: 10.1002/biof.1116] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2013] [Revised: 04/29/2013] [Accepted: 05/07/2013] [Indexed: 12/22/2022]
Abstract
Vitamin E is a generic term that refers to a family of compounds that is further divided into two subgroups called tocopherols and tocotrienols. Although all natural forms of vitamin E display potent antioxidant activity, tocotrienols are significantly more potent than tocopherols in inhibiting tumor cell growth and viability, and anticancer activity of tocotrienols is mediated independently of their antioxidant activity. In addition, the anticancer effects of tocotrienols are observed using treatment doses that have little or no effect on normal cell function or viability. This review will summarize experimental studies that have identified the intracellular mechanism mediating the anticancer effects of tocotrienols. Evidence is also provided showing that combined treatment of tocotrienol with other cancer chemotherapies can result in a synergistic inhibition in cancer cell growth and viability. Taken together, these findings strongly indicate that tocotrienols may provide significant health benefits in the prevention and/or treatment of cancer when used either alone as monotherapy or in combination with other anticancer agents.
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Affiliation(s)
- Paul W Sylvester
- Department of Basic Pharmaceutical Sciences, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA, USA
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19
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Gruber J, Staniek K, Krewenka C, Moldzio R, Patel A, Böhmdorfer S, Rosenau T, Gille L. Tocopheramine succinate and tocopheryl succinate: mechanism of mitochondrial inhibition and superoxide radical production. Bioorg Med Chem 2013; 22:684-91. [PMID: 24393721 DOI: 10.1016/j.bmc.2013.12.036] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 12/16/2013] [Accepted: 12/16/2013] [Indexed: 12/17/2022]
Abstract
Tocopherols (TOH) are lipophilic antioxidants which require the phenolic OH group for their redox activity. In contrast, non-redox active esters of α-TOH with succinate (α-TOS) were shown to possess proapoptotic activity in cancer cells. It was suggested that this activity is mediated via mitochondrial inhibition with subsequent O2(-) production triggering apoptosis and that the modification of the linker between the succinate and the lipophilic chroman may modulate this activity. However, the specific mechanism and the influence of the linker are not clear yet on the level of the mitochondrial respiratory chain. Therefore, this study systematically compared the effects of α-TOH acetate (α-TOA), α-TOS and α-tocopheramine succinate (α-TNS) in cells and submitochondrial particles (SMP). The results showed that not all cancer cell lines are highly sensitive to α-TOS and α-TNS. In HeLa cells α-TNS did more effectively reduce cell viability than α-TOS. The complex I activity of SMP was little affected by α-TNS and α-TOS while the complex II activity was much more inhibited (IC50=42±8μM α-TOS, 106±8μM α-TNS, respectively) than by α-TOA (IC50 >1000μM). Also the complex III activity was inhibited by α-TNS (IC50=137±6μM) and α-TOS (IC50=315±23μM). Oxygen consumption of NADH- or succinate-respiring SMP, involving the whole electron transfer machinery, was dose-dependently decreased by α-TOS and α-TNS, but only marginal effects were observed in the presence of α-TOA. In contrast to the similar inhibition pattern of α-TOS and α-TNS, only α-TOS triggered O2(-) formation in succinate- and NADH-respiring SMP. Inhibitor studies excluded complex I as O2(-) source and suggested an involvement of complex III in O2(-) production. In cancer cells only α-TOS was reproducibly able to increase O2(-) levels above the background level but neither α-TNS nor α-TOA. Furthermore, the stability of α-TNS in liver homogenates was significantly lower than that of α-TOS. In conclusion, this suggests that α-TNS although it has a structure similar to α-TOS is not acting via the same mechanism and that for α-TOS not only complex II but also complex III interactions are involved.
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Affiliation(s)
- Julia Gruber
- Institute of Pharmacology and Toxicology, Dept. of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria; University of Applied Sciences Wiener Neustadt (FHWN), Wiener Neustadt, Austria
| | - Katrin Staniek
- Institute of Pharmacology and Toxicology, Dept. of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Christopher Krewenka
- Institute of Medicinal Biochemistry, Dept. of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Rudolf Moldzio
- Institute of Medicinal Biochemistry, Dept. of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria
| | - Anjan Patel
- Dept. of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Stefan Böhmdorfer
- Dept. of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Thomas Rosenau
- Dept. of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Lars Gille
- Institute of Pharmacology and Toxicology, Dept. of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria.
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