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Nakatomi T, Itaya-Takahashi M, Horikoshi Y, Shimizu N, Parida IS, Jutanom M, Eitsuka T, Tanaka Y, Zingg JM, Matsura T, Nakagawa K. The difference in the cellular uptake of tocopherol and tocotrienol is influenced by their affinities to albumin. Sci Rep 2023; 13:7392. [PMID: 37149706 PMCID: PMC10164177 DOI: 10.1038/s41598-023-34584-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 05/03/2023] [Indexed: 05/08/2023] Open
Abstract
Vitamin E is classified into tocopherol (Toc) and tocotrienol (T3) based on its side chains. T3 generally has higher cellular uptake than Toc, though the responsible mechanism remains unclear. To elucidate this mechanism, we hypothesized and investigated whether serum albumin is a factor that induces such a difference in the cellular uptake of Toc and T3. Adding bovine serum albumin (BSA) to serum-depleted media increased the cellular uptake of T3 and decreased that of Toc, with varying degrees among α-, β-, γ-, and δ-analogs. Such enhanced uptake of α-T3 was not observed when cells were incubated under low temperature (the uptake of α-Toc was also reduced), suggesting that Toc and T3 bind to albumin to form a complex that results in differential cellular uptake of vitamin E. Fluorescence quenching study confirmed that vitamin E certainly bound to BSA, and that T3 showed a higher affinity than Toc. Molecular docking further indicated that the differential binding energy of Toc or T3 to BSA is due to the Van der Waals interactions via their side chain. Overall, these results suggested that the affinity of Toc and T3 to albumin differs due to their side chains, causing the difference in their albumin-mediated cellular uptake. Our results give a better mechanistic insight into the physiological action of vitamin E.
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Affiliation(s)
- Takashi Nakatomi
- Laboratory of Food Function Analysis, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8572, Japan
| | - Mayuko Itaya-Takahashi
- Laboratory of Food Function Analysis, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8572, Japan
| | - Yosuke Horikoshi
- Division of Medical Biochemistry, Department of Pathophysiological and Therapeutic Sciences, Tottori University Faculty of Medicine, 86 Nishi-cho, Yonago, 683-8503, Japan
| | - Naoki Shimizu
- Laboratory of Food Function Analysis, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8572, Japan
| | - Isabella Supardi Parida
- Laboratory of Food Function Analysis, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8572, Japan
| | - Mirinthorn Jutanom
- Laboratory of Food Function Analysis, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8572, Japan
| | - Takahiro Eitsuka
- Laboratory of Food Function Analysis, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8572, Japan
| | - Yoshikazu Tanaka
- Applied Biological Molecular Science, Graduate School of Life Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Jean-Marc Zingg
- Department of Biochemistry and Molecular Biology, University of Miami, 1011 NW 15th St, Miami, FL, 33136-1019, USA
| | - Tatsuya Matsura
- Division of Medical Biochemistry, Department of Pathophysiological and Therapeutic Sciences, Tottori University Faculty of Medicine, 86 Nishi-cho, Yonago, 683-8503, Japan
- Department of Nutritional Sciences, Faculty of Human Ecology, Yasuda Women's University, 6-13-1 Yasuhigashi, Asaminami-ku, Hiroshima, 731-0153, Japan
| | - Kiyotaka Nakagawa
- Laboratory of Food Function Analysis, Graduate School of Agricultural Science, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8572, Japan.
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Magalingam KB, Somanath SD, Md S, Haleagrahara N, Fu JY, Selvaduray KR, Radhakrishnan AK. Tocotrienols protect differentiated SH-SY5Y human neuroblastoma cells against 6-hydroxydopamine-induced cytotoxicity by ameliorating dopamine biosynthesis and dopamine receptor D2 gene expression. Nutr Res 2022; 98:27-40. [DOI: 10.1016/j.nutres.2021.09.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 09/20/2021] [Accepted: 09/20/2021] [Indexed: 11/15/2022]
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3
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Zakharova IO, Akhmetshina AO, Bayunova LV, Kizhaeva LR, Avrova NF. The Effect of Alpha-Tocopherol on
Viability of PC12 Cells during Oxidative Stress and Expression of
Genes Encoding Pro- and Anti-Apoptotic Mitochondrial Proteins, SOD2
and Transcription Factors NRF-1, NRF-2 and TFAM. J EVOL BIOCHEM PHYS+ 2020. [DOI: 10.1134/s0022093020030084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Pipová Kokošová N, Kisková T, Vilhanová K, Štafuriková A, Jendželovský R, Račeková E, Šmajda B. Melatonin mitigates hippocampal and cognitive impairments caused by prenatal irradiation. Eur J Neurosci 2020; 52:3575-3594. [PMID: 31985866 DOI: 10.1111/ejn.14687] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 01/10/2020] [Accepted: 01/17/2020] [Indexed: 12/11/2022]
Abstract
Formation of new neurons and glial cells in the brain is taking place in mammals not only during prenatal embryogenesis but also during adult life. As an enhancer of oxidative stress, ionizing radiation represents a potent inhibitor of neurogenesis and gliogenesis in the brain. It is known that the pineal hormone melatonin is a potent free radical scavenger and counteracts inflammation and apoptosis in brain injuries. The aim of our study was to establish the effects of melatonin on cells in the hippocampus and selected forms of behaviour in prenatally irradiated rats. The male progeny of irradiated (1 Gy of gamma rays; n = 38) and sham-irradiated mothers (n = 19), aged 3 weeks or 2 months, were used in the experiment. Melatonin was administered daily in drinking water (4 mg/kg b. w.) to a subset of animals from each age group. Prenatal irradiation markedly suppressed proliferative activity in the dentate gyrus in both age groups. Melatonin significantly increased the number of proliferative BrdU-positive cells in hilus of young irradiated animals, and the number of mature NeuN-positive neurons in hilus and granular cell layer of the dentate gyrus in these rats and in CA1 region of adult irradiated rats. Moreover, melatonin significantly improved the spatial memory impaired by irradiation, assessed in Morris water maze. A significant correlation between the number of proliferative cells and cognitive performances was found, too. Our study indicates that melatonin may decrease the loss of hippocampal neurons in the CA1 region and improve cognitive abilities after irradiation.
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Affiliation(s)
- Natália Pipová Kokošová
- Department of Animal Physiology, Faculty of Science, Institute of Biology and Ecology, P. J. Šafárik University in Košice, Košice, Slovak Republic
| | - Terézia Kisková
- Department of Animal Physiology, Faculty of Science, Institute of Biology and Ecology, P. J. Šafárik University in Košice, Košice, Slovak Republic
| | - Katarína Vilhanová
- Department of Animal Physiology, Faculty of Science, Institute of Biology and Ecology, P. J. Šafárik University in Košice, Košice, Slovak Republic
| | - Andrea Štafuriková
- Department of Animal Physiology, Faculty of Science, Institute of Biology and Ecology, P. J. Šafárik University in Košice, Košice, Slovak Republic
| | - Rastislav Jendželovský
- Department of Cell Biology, Faculty of Science, Institute of Biology and Ecology, P. J. Šafárik University in Košice, Košice, Slovak Republic
| | - Enikő Račeková
- Institute of Neurobiology, Biomedical Research Center, Slovak Academy of Sciences, Košice, Slovak Republic
| | - Beňadik Šmajda
- Department of Animal Physiology, Faculty of Science, Institute of Biology and Ecology, P. J. Šafárik University in Košice, Košice, Slovak Republic
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5
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Musa I, Khaza’ai H, Abdul Mutalib MS, Yusuf F, Sanusi J, Chang SK. Effects of oil palm tocotrienol rich fraction on the viability and morphology of astrocytes injured with glutamate. FOOD BIOSCI 2017. [DOI: 10.1016/j.fbio.2017.10.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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Zakharova IO, Sokolova TV, Vlasova YA, Bayunova LV, Rychkova MP, Avrova NF. α-Tocopherol at Nanomolar Concentration Protects Cortical Neurons against Oxidative Stress. Int J Mol Sci 2017; 18:ijms18010216. [PMID: 28117722 PMCID: PMC5297845 DOI: 10.3390/ijms18010216] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/08/2017] [Accepted: 01/14/2017] [Indexed: 12/14/2022] Open
Abstract
The aim of the present work is to study the mechanism of the α-tocopherol (α-T) protective action at nanomolar and micromolar concentrations against H2O2-induced brain cortical neuron death. The mechanism of α-T action on neurons at its nanomolar concentrations characteristic for brain extracellular space has not been practically studied yet. Preincubation with nanomolar and micromolar α-T for 18 h was found to increase the viability of cortical neurons exposed to H2O2; α-T effect was concentration-dependent in the nanomolar range. However, preincubation with nanomolar α-T for 30 min was not effective. Nanomolar and micromolar α-T decreased the reactive oxygen species accumulation induced in cortical neurons by the prooxidant. Using immunoblotting it was shown that preincubation with α-T at nanomolar and micromolar concentrations for 18 h prevented Akt inactivation and decreased PKCδ activation induced in cortical neurons by H2O2. α-T prevented the ERK1/2 sustained activation during 24 h caused by H2O2. α-T at nanomolar and micromolar concentrations prevented a great increase of the proapoptotic to antiapoptotic proteins (Bax/Bcl-2) ratio, elicited by neuron exposure to H2O2. The similar neuron protection mechanism by nanomolar and micromolar α-T suggests that a “more is better” approach to patients’ supplementation with vitamin E or α-T is not reasonable.
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Affiliation(s)
- Irina O Zakharova
- Department of Molecular Endocrinology and Neurochemistry, I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Thorez avenue, 44, Saint-Petersburg 194223, Russia.
| | - Tatiana V Sokolova
- Department of Molecular Endocrinology and Neurochemistry, I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Thorez avenue, 44, Saint-Petersburg 194223, Russia.
| | - Yulia A Vlasova
- Department of Molecular Endocrinology and Neurochemistry, I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Thorez avenue, 44, Saint-Petersburg 194223, Russia.
- Preventive Medicine Department, Mechnikov North-West StateMedical University, Saint-Petersburg, Kirochnaya ul. 41, Saint-Petersburg 191015, Russia.
| | - Liubov V Bayunova
- Department of Molecular Endocrinology and Neurochemistry, I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Thorez avenue, 44, Saint-Petersburg 194223, Russia.
| | - Maria P Rychkova
- Department of Molecular Endocrinology and Neurochemistry, I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Thorez avenue, 44, Saint-Petersburg 194223, Russia.
| | - Natalia F Avrova
- Department of Molecular Endocrinology and Neurochemistry, I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences, Thorez avenue, 44, Saint-Petersburg 194223, Russia.
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7
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Vlasova YA, Zakharova IO, Avrova NF. The effects of alpha-tocoferol and H2O2 on the mitochondrial membrane potential and Bax/Bcl-xL ratio in PC12 cells. NEUROCHEM J+ 2016. [DOI: 10.1134/s1819712416040152] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Zalfa C, Verpelli C, D'Avanzo F, Tomanin R, Vicidomini C, Cajola L, Manara R, Sala C, Scarpa M, Vescovi AL, De Filippis L. Glial degeneration with oxidative damage drives neuronal demise in MPSII disease. Cell Death Dis 2016; 7:e2331. [PMID: 27512952 PMCID: PMC5108318 DOI: 10.1038/cddis.2016.231] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Revised: 06/22/2016] [Accepted: 07/04/2016] [Indexed: 12/13/2022]
Abstract
Mucopolysaccharidosis type II (MPSII) is a lysosomal storage disorder due to the deficit of the iduronate 2-sulfatase (IDS) enzyme, causing progressive neurodegeneration in patients. Neural stem cells (NSCs) derived from the IDS-ko mouse can recapitulate MPSII pathogenesis in vitro. In differentiating IDS-ko NSCs and in the aging IDS-ko mouse brain, glial degeneration precedes neuronal degeneration. Here we show that pure IDS-ko NSC-derived astrocytes are selectively able to drive neuronal degeneration when cocultured with healthy neurons. This phenotype suggests concurrent oxidative damage with metabolic dysfunction. Similar patterns were observed in murine IDS-ko animals and in human MPSII brains. Most importantly, the mutant phenotype of IDS-ko astrocytes was reversed by low oxygen conditions and treatment with vitamin E, which also reversed the toxic effect on cocultured neurons. Moreover, at very early stages of disease we detected in vivo the development of a neuroinflammatory background that precedes astroglial degeneration, thus suggesting a novel model of MPSII pathogenesis, with neuroinflammation preceding glial degeneration, which is finally followed by neuronal death. This hypothesis is also consistent with the progression of white matter abnormalities in MPSII patients. Our study represents a novel breakthrough in the elucidation of MPSII brain pathogenesis and suggests the antioxidant molecules as potential therapeutic tools to delay MPSII onset and progression.
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Affiliation(s)
- Cristina Zalfa
- Department of Biotechnology and Biosciences, University Milan Bicocca, Piazza della Scienza 2, Milano 20126, Italy
| | - Chiara Verpelli
- CNR Neuroscience Institute and Department of Biotechnology and Translational Medicine, University of Milan, Via Vanvitelli 32, Milano 20129, Italy
| | - Francesca D'Avanzo
- Laboratory of Diagnosis and Therapy of Lysosomal Disorders, Department of Women's and Children's Health, University of Padova, Via Giustiniani 3, Padova 35128, Italy
| | - Rosella Tomanin
- Laboratory of Diagnosis and Therapy of Lysosomal Disorders, Department of Women's and Children's Health, University of Padova, Via Giustiniani 3, Padova 35128, Italy
| | - Cinzia Vicidomini
- CNR Neuroscience Institute and Department of Biotechnology and Translational Medicine, University of Milan, Via Vanvitelli 32, Milano 20129, Italy
| | | | - Renzo Manara
- Department of Neuroradiology, University of Salerno, Via S Allende, Baronissi 84081, Italy
| | - Carlo Sala
- CNR Neuroscience Institute and Department of Biotechnology and Translational Medicine, University of Milan, Via Vanvitelli 32, Milano 20129, Italy
| | - Maurizio Scarpa
- Laboratory of Diagnosis and Therapy of Lysosomal Disorders, Department of Women's and Children's Health, University of Padova, Via Giustiniani 3, Padova 35128, Italy
| | - Angelo Luigi Vescovi
- Department of Biotechnology and Biosciences, University Milan Bicocca, Piazza della Scienza 2, Milano 20126, Italy.,Stemgen Srl, Viale Ca' Granda, Milano, Italy.,Stem Cells Laboratory, Cell Factory and Biobank, Azienda Ospedaliera 'Santa Maria', Viale Tristano da Joannuccio 1, Terni 05100, Italy.,Casa Sollievo della Sofferenza, Viale Cappuccini 2, San Giovanni Rotondo (FG) 71013, Italy
| | - Lidia De Filippis
- Department of Biotechnology and Biosciences, University Milan Bicocca, Piazza della Scienza 2, Milano 20126, Italy.,Casa Sollievo della Sofferenza, Viale Cappuccini 2, San Giovanni Rotondo (FG) 71013, Italy
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9
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Tan JK, Then SM, Mazlan M, Raja Abdul Rahman RNZ, Jamal R, Wan Ngah WZ. Gamma-tocotrienol acts as a BH3 mimetic to induce apoptosis in neuroblastoma SH-SY5Y cells. J Nutr Biochem 2016; 31:28-37. [DOI: 10.1016/j.jnutbio.2015.12.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 12/09/2015] [Accepted: 12/29/2015] [Indexed: 11/17/2022]
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10
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Tan JK, Then SM, Mazlan M, Jamal R, Ngah WZW. Vitamin E, γ-tocotrienol, Protects Against Buthionine Sulfoximine-Induced Cell Death by Scavenging Free Radicals in SH-SY5Y Neuroblastoma Cells. Nutr Cancer 2016; 68:507-17. [PMID: 27008382 DOI: 10.1080/01635581.2016.1153671] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The induction of reactive oxygen species (ROS) to selectively kill cancer cells is an important feature of radiotherapy and various chemotherapies. Depletion of glutathione can induce apoptosis in cancer cells or sensitize them to anticancer treatments intended to modulate ROS levels. In contrast, antioxidants protect cancer cells from oxidative stress-induced cell death by scavenging ROS. The role of exogenous antioxidants in cancer cells under oxidative insults remains controversial and unclear. This study aimed to identify protective pathways modulated by γ-tocotrienol (γT3), an isomer of vitamin E, in human neuroblastoma SH-SY5Y cells under oxidative stress. Using buthionine sulfoximine (BSO) as an inhibitor of glutathione synthesis, we found that BSO treatment reduced the viability of SH-SY5Y cells. BSO induced cell death by increasing apoptosis, decreased the level of reduced glutathione (GSH), and increased ROS levels in SH-SY5Y cells. Addition of γT3 increased the viability of BSO-treated cells, suppressed apoptosis, and decreased the ROS level induced by BSO, while the GSH level was unaffected. These results suggest that decreasing GSH levels by BSO increased ROS levels, leading to apoptosis in SH-SY5Y cells. γT3 attenuated the BSO-induced cell death by scavenging free radicals.
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Affiliation(s)
- Jen-Kit Tan
- a UKM Medical Molecular Biology Institute, Universiti Kebangsaan Malaysia Medical Center , Kuala Lumpur , Malaysia
| | - Sue-Mian Then
- a UKM Medical Molecular Biology Institute, Universiti Kebangsaan Malaysia Medical Center , Kuala Lumpur , Malaysia
| | - Musalmah Mazlan
- b Faculty of Medicine, Universiti Teknologi MARA , Selangor , Malaysia
| | - Rahman Jamal
- a UKM Medical Molecular Biology Institute, Universiti Kebangsaan Malaysia Medical Center , Kuala Lumpur , Malaysia
| | - Wan Zurinah Wan Ngah
- a UKM Medical Molecular Biology Institute, Universiti Kebangsaan Malaysia Medical Center , Kuala Lumpur , Malaysia.,c Department of Biochemistry , Faculty of Medicine, Universiti Kebangsaan Malaysia Medical Center , Kuala Lumpur , Malaysia
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11
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New antioxidant drugs for neonatal brain injury. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:108251. [PMID: 25685254 PMCID: PMC4313724 DOI: 10.1155/2015/108251] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 12/19/2014] [Indexed: 11/17/2022]
Abstract
The brain injury concept covers a lot of heterogeneity in terms of aetiology involving multiple factors, genetic, hemodynamic, metabolic, nutritional, endocrinological, toxic, and infectious mechanisms, acting in antenatal or postnatal period. Increased vulnerability of the immature brain to oxidative stress is documented because of the limited capacity of antioxidant enzymes and the high free radicals (FRs) generation in rapidly growing tissue. FRs impair transmembrane enzyme Na+/K+-ATPase activity resulting in persistent membrane depolarization and excessive release of FR and excitatory aminoacid glutamate. Besides being neurotoxic, glutamate is also toxic to oligodendroglia, via FR effects. Neuronal cells die of oxidative stress. Excess of free iron and deficient iron/binding metabolising capacity are additional features favouring oxidative stress in newborn. Each step in the oxidative injury cascade has become a potential target for neuroprotective intervention. The administration of antioxidants for suspected or proven brain injury is still not accepted for clinical use due to uncertain beneficial effects when treatments are started after resuscitation of an asphyxiated newborn. The challenge for the future is the early identification of high-risk babies to target a safe and not toxic antioxidant therapy in combination with standard therapies to prevent brain injury and long-term neurodevelopmental impairment.
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12
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Selvaraju TR, Khaza'ai H, Vidyadaran S, Abd Mutalib MS, Vasudevan R. The neuroprotective effects of tocotrienol rich fraction and alpha tocopherol against glutamate injury in astrocytes. Bosn J Basic Med Sci 2014; 14:195-204. [PMID: 25428670 DOI: 10.17305/bjbms.2014.4.91] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 09/12/2014] [Accepted: 09/12/2014] [Indexed: 01/01/2023] Open
Abstract
Tocotrienol rich fraction (TRF) is an extract of palm oil, which consists of 25% alpha tocopherol (α-TCP) and 75% tocotrienols. TRF has been shown to possess potent antioxidant, anti-inflammatory, anticancer, neuroprotection, and cholesterol lowering activities. Glutamate is the main excitatory amino acid neurotransmitter in the central nervous system of mammalian, which can be excitotoxic, and it has been suggested to play a key role in neurodegenerative disorders like Parkinson's and Alzheimer's diseases. In this present study, the effects of vitamin E (TRF and α-TCP) in protecting astrocytes against glutamate injury were elucidated. Astrocytes induced with 180 mM of glutamate lead to significant cell death. However, glutamate mediated cytotoxicity was diminished via pre and post supplementation of TRF and α-TCP. Hence, vitamin E acted as a potent antioxidant agent in recovering mitochondrial injury due to elevated oxidative stress, and enhanced better survivability upon glutamate toxicity.
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Affiliation(s)
- Thilaga Rati Selvaraju
- Biochemistry Unit, Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, 43400 Selangor, Malaysia.
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13
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Li Y, Li Y, Wu Q, Ye H, Sun L, Ye B, Wang D. High concentration of vitamin E decreases thermosensation and thermotaxis learning and the underlying mechanisms in the nematode Caenorhabditis elegans. PLoS One 2013; 8:e71180. [PMID: 23951104 PMCID: PMC3741368 DOI: 10.1371/journal.pone.0071180] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Accepted: 06/28/2013] [Indexed: 11/19/2022] Open
Abstract
α-tocopherol is a powerful liposoluble antioxidant and the most abundant isoform of vitamin E in the body. Under normal physiological conditions, adverse effects of relatively high concentration of vitamin E on organisms and the underlying mechanisms are still largely unclear. In the present study, we used the nematode Caenorhabditis elegans as an in vivo assay system to investigate the possible adverse effects of high concentration of vitamin E on thermosensation and thermotaxis learning and the underlying mechanisms. Our data show that treatment with 100-200 µg/mL of vitamin E did not noticeably influence both thermosensation and thermotaxis learning; however, treatment with 400 µg/mL of vitamin E altered both thermosensation and thermotaxis learning. The observed decrease in thermotaxis learning in 400 µg/mL of vitamin E treated nematodes might be partially due to the moderate but significant deficits in thermosensation, but not due to deficits in locomotion behavior or perception to food and starvation. Treatment with 400 µg/mL of vitamin E did not noticeably influence the morphology of GABAergic neurons, but significantly decreased fluorescent intensities of the cell bodies in AFD sensory neurons and AIY interneurons, required for thermosensation and thermotaxis learning control. Treatment with 400 µg/mL of vitamin E affected presynaptic function of neurons, but had no remarkable effects on postsynaptic function. Moreover, promotion of synaptic transmission by activating PKC-1 effectively retrieved deficits in both thermosensation and thermotaxis learning induced by 400 µg/mL of vitamin E. Therefore, relatively high concentrations of vitamin E administration may cause adverse effects on thermosensation and thermotaxis learning by inducing damage on the development of specific neurons and presynaptic function under normal physiological conditions in C. elegans.
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Affiliation(s)
- Yiping Li
- Key Laboratory of Developmental Genes and Human Diseases in Ministry of Education, Medical School of Southeast University, Nanjing, China
| | - Yinxia Li
- Key Laboratory of Developmental Genes and Human Diseases in Ministry of Education, Medical School of Southeast University, Nanjing, China
| | - Qiuli Wu
- Key Laboratory of Developmental Genes and Human Diseases in Ministry of Education, Medical School of Southeast University, Nanjing, China
| | - Huayue Ye
- Key Laboratory of Developmental Genes and Human Diseases in Ministry of Education, Medical School of Southeast University, Nanjing, China
- College of Life Sciences and Technology, China Pharmaceutical University, Nanjing, China
| | - Lingmei Sun
- Key Laboratory of Developmental Genes and Human Diseases in Ministry of Education, Medical School of Southeast University, Nanjing, China
| | - Boping Ye
- College of Life Sciences and Technology, China Pharmaceutical University, Nanjing, China
| | - Dayong Wang
- Key Laboratory of Developmental Genes and Human Diseases in Ministry of Education, Medical School of Southeast University, Nanjing, China
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14
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Effects of Low-Dose versus High-Dose γ-Tocotrienol on the Bone Cells Exposed to the Hydrogen Peroxide-Induced Oxidative Stress and Apoptosis. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:680834. [PMID: 22956976 PMCID: PMC3432387 DOI: 10.1155/2012/680834] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Accepted: 07/24/2012] [Indexed: 11/18/2022]
Abstract
Oxidative stress and apoptosis can disrupt the bone formation activity of osteoblasts which can lead to osteoporosis. This study was conducted to investigate the effects of γ-tocotrienol on lipid peroxidation, antioxidant enzymes activities, and apoptosis of osteoblast exposed to hydrogen peroxide (H2O2). Osteoblasts were treated with 1, 10, and 100 μM of γ-tocotrienol for 24 hours before being exposed to 490 μM (IC50) H2O2 for 2 hours. Results showed that γ-tocotrienol prevented the malondialdehyde (MDA) elevation induced by H2O2 in a dose-dependent manner. As for the antioxidant enzymes assays, all doses of γ-tocotrienol were able to prevent the reduction in SOD and CAT activities, but only the dose of 1 μM of GTT was able to prevent the reduction in GPx. As for the apoptosis assays, γ-tocotrienol was able to reduce apoptosis at the dose of 1 and 10 μM. However, the dose of 100 μM of γ-tocotrienol induced an even higher apoptosis than H2O2. In conclusion, low doses of γ-tocotrienol offered protection for osteoblasts against H2O2 toxicity, but itself caused toxicity at the high doses.
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15
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Then SM, Sanfeliu C, Top GM, Wan Ngah WZ, Mazlan M. γ-Tocotrienol does not substantially protect DS neurons from hydrogen peroxide-induced oxidative injury. Nutr Metab (Lond) 2012; 9:1. [PMID: 22217149 PMCID: PMC3285086 DOI: 10.1186/1743-7075-9-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 01/05/2012] [Indexed: 01/06/2023] Open
Abstract
Background Down syndrome (DS) neurons are more susceptible to oxidative stress and previous studies have shown that vitamin E was able to reduce oxidative stress and improve DS neurons' viability. Therefore, this study was done to investigate the protective role of γ-tocotrienol (γT3) in DS neurons from hydrogen peroxide (H2O2) -induced oxidative stress. The pro-apoptosis tendency of γT3 was compared to α-tocopherol (αT) in non-stress condition as well. Methods Primary culture of DS and euploid neurons were divided into six groups of treatment: control, H2O2, γT3 pre-treatment with H2O2, γT3 only, αT pre-treatment with H2O2 and αT only. The treatments were assessed by MTS assay and apoptosis assay by single-stranded DNA (ssDNA) apoptosis ELISA assay, Hoechst and Neu-N immunofluorescence staining. The cellular uptake of γT3 and αT was determined by HPLC while protein expressions were determined by Western blot. Comparison between groups was made by the Student's t test, one-way ANOVA and Bonferroni adjustment as well as two-way ANOVA for multiple comparisons. Results One day incubation of γT3 was able to reduced apoptosis of DS neurons by 10%, however γT3 was cytotoxic at longer incubation period (14 days) and at concentrations ≥ 100 μM. Pre-treatment of αT and γT3 only attenuate apoptosis and increase cell viability in H2O2-treated DS and euploid neurons by 10% in which the effects were minimal to maintain most of the DS cells' morphology. γT3 act as a free radical scavenger by reducing ROS generated by H2O2. In untreated controls, DS neurons showed lower Bcl-2/Bax ratio and p53 expression compared to normal neurons, while cPKC and PKC-δ expressions were higher in DS neurons. On the other hand, pre-treatment of γT3 in H2O2-treated DS neurons have reduced Bcl-2/Bax ratio, which was not shown in euploid neurons. This suggests that pre-treatment of γT3 did not promote DS cell survival. Meanwhile γT3 and αT treatments without H2O2 as well as pre-treatment of γT3 and αT induced changes in cPKC and PKC-δ expression in DS neurons suggesting interaction of γT3 and αT with PKC activity. Conclusion Our study suggests that γT3 pre-treatment are not sufficient to protect DS neurons from H2O2-induced oxidative assault, instead induced the apoptosis process.
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Affiliation(s)
- Sue-Mian Then
- UKM Medical Molecular Biology Institute (UMBI), Universiti Kebangsaan Malaysia (UKM), Kuala Lumpur, Malaysia.
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16
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Frank J, Chin XWD, Schrader C, Eckert GP, Rimbach G. Do tocotrienols have potential as neuroprotective dietary factors? Ageing Res Rev 2012; 11:163-80. [PMID: 21763788 DOI: 10.1016/j.arr.2011.06.006] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 06/28/2011] [Accepted: 06/30/2011] [Indexed: 11/17/2022]
Abstract
Tocotrienols (T(3)) belong to the family of vitamin E compounds (α-, β-, γ-, δ-tocopherols and -tocotrienols) and have unique biological properties that make them potential neuroprotective dietary factors. In addition to their antioxidant activity, T(3) at micromolar concentrations exert cholesterol-lowering activities in cells, animal models and some, but not all, human studies by means of inhibition of the activity of the rate-limiting enzyme in cholesterol biosynthesis, 3-hydroxy-3-methylglutaryl coenzyme A reductase. At lower concentrations (∼10 nmol/L), T(3) modulate signalling pathways involved in neuronal cell death in cell culture experiments. Targets of T(3) include prenyl transferases, non-receptor tyrosine kinase, phospholipase A(2), 12-lipoxygenase, cyclooxygenase-2, and nuclear factor κB. The low bioavailability and rapid excretion of T(3) represents a major hurdle in their preventive use. Fasting plasma concentrations, even after supplementation with high doses, are below 1 μmol/L. T(3) bioavailability may be enhanced by ingestion with a high-fat meal, self-emulsifying drug delivery systems, or phytochemicals that inhibit T(3) metabolism and excretion. T(3) have no known adverse effects when consumed as part of a normal diet and the studies reviewed here support the notion that they may have potential as neuroprotective agents. However, experiments in relevant animal models and randomised human intervention trials addressing the neuroprotection mediated by T(3) are scarce and, thus, highly warranted.
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Affiliation(s)
- Jan Frank
- Institute of Biological Chemistry and Nutrition, University of Hohenheim, Stuttgart, Germany.
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17
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Miller SL, Wallace EM, Walker DW. Antioxidant therapies: a potential role in perinatal medicine. Neuroendocrinology 2012; 96:13-23. [PMID: 22377769 DOI: 10.1159/000336378] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 12/30/2011] [Indexed: 11/19/2022]
Abstract
Pregnancies complicated by impaired placentation, acute severe reductions in oxygen supply to the fetus, or intrauterine infection are associated with oxidative stress to the mother and developing baby. Such oxidative stress is characterized as an upregulation in the production of oxidative or nitrative free radicals and a concomitant decrease in the availability of antioxidant species, thereby creating a state of fetoplacental oxidative imbalance. Recently, there has been a good deal of interest in the potential for the use of antioxidant therapies in the perinatal period to protect the fetus, particularly the developing brain, against oxidative stress in complications of pregnancy and birth. This review will examine why the immature brain is particularly susceptible to oxidative imbalance and will provide discussion on antioxidant treatments currently receiving attention in the adult and perinatal literature - allopurinol, melatonin, α-lipoic acid, and vitamins C and E. In addition, we aim to address the interaction between oxidative stress and the fetal inflammatory response, an interaction that may be vital when proposing antioxidant or other neuroprotective strategies.
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Affiliation(s)
- S L Miller
- The Ritchie Centre, Monash Institute of Medical Research, Clayton, Vic., Australia
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Nowak G, Bakajsova D, Hayes C, Hauer-Jensen M, Compadre CM. γ-Tocotrienol protects against mitochondrial dysfunction and renal cell death. J Pharmacol Exp Ther 2011; 340:330-8. [PMID: 22040679 DOI: 10.1124/jpet.111.186882] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Oxidative stress is a major mechanism of a variety of renal diseases. Tocopherols and tocotrienols are well known antioxidants. This study aimed to determine whether γ-tocotrienol (GT3) protects against mitochondrial dysfunction and renal proximal tubular cell (RPTC) injury caused by oxidants. Primary cultures of RPTCs were injured by using tert-butyl hydroperoxide (TBHP) in the absence and presence of GT3 or α-tocopherol (AT). Reactive oxygen species (ROS) production increased 300% in TBHP-injured RPTCs. State 3 respiration, oligomycin-sensitive respiration, and respiratory control ratio (RCR) decreased 50, 63, and 47%, respectively. The number of RPTCs with polarized mitochondria decreased 54%. F₀F₁-ATPase activity and ATP content decreased 31 and 65%, respectively. Cell lysis increased from 3% in controls to 26 and 52% at 4 and 24 h, respectively, after TBHP exposure. GT3 blocked ROS production, ameliorated decreases in state 3 and oligomycin-sensitive respirations and F₀F₁-ATPase activity, and maintained RCR and mitochondrial membrane potential (ΔΨ(m)) in injured RPTCs. GT3 maintained ATP content, blocked RPTC lysis at 4 h, and reduced it to 13% at 24 h after injury. Treatment with equivalent concentrations of AT did not block ROS production and cell lysis and moderately improved mitochondrial respiration and coupling. This is the first report demonstrating the protective effects of GT3 against RPTC injury by: 1) decreasing production of ROS, 2) improving mitochondrial respiration, coupling, ΔΨ(m), and F₀F₁-ATPase function, 3) maintaining ATP levels, and 4) preventing RPTC lysis. Our data suggest that GT3 is superior to AT in protecting RPTCs against oxidant injury and may prove therapeutically valuable for preventing renal injury associated with oxidative stress.
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Affiliation(s)
- Grazyna Nowak
- Department of Pharmaceutical Sciences, University of Arkansas for Medical Sciences, 4301 West Markham St., MS 522-3, Little Rock, AR 72205, USA.
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Why tocotrienols work better: insights into the in vitro anti-cancer mechanism of vitamin E. GENES AND NUTRITION 2011; 7:29-41. [PMID: 21505906 DOI: 10.1007/s12263-011-0219-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Accepted: 03/24/2011] [Indexed: 12/23/2022]
Abstract
The selective constraint of liver uptake and the sustained metabolism of tocotrienols (T3) demonstrate the need for a prompt detoxification of this class of lipophilic vitamers, and thus the potential for cytotoxic effects in hepatic and extra-hepatic tissues. Hypomethylated (γ and δ) forms of T3 show the highest in vitro and in vivo metabolism and are also the most potent natural xenobiotics of the entire vitamin E family of compounds. These stimulate a stress response with the induction of detoxification and antioxidant genes. Depending on the intensity of this response, these genes may confer cell protection or alternatively they stimulate a senescence-like phenotype with cell cycle inhibition or even mitochondrial toxicity and apoptosis. In cancer cells, the uptake rate and thus the cell content of these vitamers is again higher for the hypomethylated forms, and it is the critical factor that drives the dichotomy between protection and toxicity responses to different T3 forms and doses. These aspects suggest the potential for marked biological activity of hypomethylated "highly metabolized" T3 that may result in cytoprotection and cancer prevention or even chemotherapeutic effects. Cytotoxicity and metabolism of hypomethylated T3 have been extensively investigated in vitro using different cell model systems that will be discussed in this review paper as regard molecular mechanisms and possible relevance in cancer therapy.
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Abstract
The developing brain is particularly vulnerable to reactive oxygen and reactive nitrogen species-mediated damage because of its high concentrations of unsaturated fatty acids, high rate of oxygen consumption, low concentrations of antioxidants, high content of metals catalyzing free radical formation, and large proportion of sensitive immature cells. In this review, we outline the dynamic changes of energy resources, metabolic requirements, and endogenous free radical scavenging systems during physiologic brain development. We further discuss the involvement of oxidative stress in the pathogenesis of neuronal death after exposure of the infant brain to hyperoxia, hypoxia/ischemia, sedative drugs, ethanol, and mechanical trauma. Several approaches have been developed to combat oxidative stress, but neuroprotective treatment strategies are limited in the clinical setting.
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Affiliation(s)
- Chrysanthy Ikonomidou
- Department of Neurology, University of Wisconsin, 600 Highland Avenue, Madison, WI 53792, USA.
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21
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Maiese K, Chong ZZ, Shang YC, Hou J. Novel avenues of drug discovery and biomarkers for diabetes mellitus. J Clin Pharmacol 2011; 51:128-52. [PMID: 20220043 PMCID: PMC3033756 DOI: 10.1177/0091270010362904] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Globally, developed nations spend a significant amount of their resources on health care initiatives that poorly translate into increased population life expectancy. As an example, the United States devotes 16% of its gross domestic product to health care, the highest level in the world, but falls behind other nations that enjoy greater individual life expectancy. These observations point to the need for pioneering avenues of drug discovery to increase life span with controlled costs. In particular, innovative drug development for metabolic disorders such as diabetes mellitus becomes increasingly critical given that the number of diabetic people will increase exponentially over the next 20 years. This article discusses the elucidation and targeting of novel cellular pathways that are intimately tied to oxidative stress in diabetes mellitus for new treatment strategies. Pathways that involve wingless, β-nicotinamide adenine dinucleotide (NAD(+)) precursors, and cytokines govern complex biological pathways that determine both cell survival and longevity during diabetes mellitus and its complications. Furthermore, the role of these entities as biomarkers for disease can further enhance their utility irrespective of their treatment potential. Greater understanding of the intricacies of these unique cellular mechanisms will shape future drug discovery for diabetes mellitus to provide focused clinical care with limited or absent long-term complications.
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Affiliation(s)
- Kenneth Maiese
- Department of Neurology, 8C-1 UHC, Wayne State University School of Medicine, 4201 St. Antoine, Detroit, MI 48201, USA.
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Tan SW, Ramasamy R, Abdullah M, Vidyadaran S. Inhibitory effects of palm α-, γ- and δ-tocotrienol on lipopolysaccharide-induced nitric oxide production in BV2 microglia. Cell Immunol 2011; 271:205-9. [DOI: 10.1016/j.cellimm.2011.07.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 06/27/2011] [Accepted: 07/14/2011] [Indexed: 10/18/2022]
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Maiese K, Shang YC, Chong ZZ, Hou J. Diabetes mellitus: channeling care through cellular discovery. Curr Neurovasc Res 2010; 7:59-64. [PMID: 20158461 DOI: 10.2174/156720210790820217] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Accepted: 12/29/2009] [Indexed: 12/13/2022]
Abstract
Diabetes mellitus (DM) impacts a significant portion of the world's population and care for this disorder places an economic burden on the gross domestic product for any particular country. Furthermore, both Type 1 and Type 2 DM are becoming increasingly prevalent and there is increased incidence of impaired glucose tolerance in the young. The complications of DM are protean and can involve multiple systems throughout the body that are susceptible to the detrimental effects of oxidative stress and apoptotic cell injury. For these reasons, innovative strategies are necessary for the implementation of new treatments for DM that are generated through the further understanding of cellular pathways that govern the pathological consequences of DM. In particular, both the precursor for the coenzyme beta-nicotinamide adenine dinucleotide (NAD(+)), nicotinamide, and the growth factor erythropoietin offer novel platforms for drug discovery that involve cellular metabolic homeostasis and inflammatory cell control. Interestingly, these agents and their tightly associated pathways that consist of cell cycle regulation, protein kinase B, forkhead transcription factors, and Wnt signaling also function in a broader sense as biomarkers for disease onset and progression.
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Affiliation(s)
- Kenneth Maiese
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201, USA.
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24
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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.
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Affiliation(s)
- Francesco Galli
- Department of Internal Medicine, Laboratory of Clinical Biochemistry and Nutrition, University of Perugia, Perugia, Italy
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25
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Maiese K, Chong ZZ, Hou J, Shang YC. The vitamin nicotinamide: translating nutrition into clinical care. Molecules 2009; 14:3446-85. [PMID: 19783937 PMCID: PMC2756609 DOI: 10.3390/molecules14093446] [Citation(s) in RCA: 173] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2009] [Revised: 09/08/2009] [Accepted: 09/08/2009] [Indexed: 12/13/2022] Open
Abstract
Nicotinamide, the amide form of vitamin B(3) (niacin), is changed to its mononucleotide compound with the enzyme nicotinic acide/nicotinamide adenylyltransferase, and participates in the cellular energy metabolism that directly impacts normal physiology. However, nicotinamide also influences oxidative stress and modulates multiple pathways tied to both cellular survival and death. During disorders that include immune system dysfunction, diabetes, and aging-related diseases, nicotinamide is a robust cytoprotectant that blocks cellular inflammatory cell activation, early apoptotic phosphatidylserine exposure, and late nuclear DNA degradation. Nicotinamide relies upon unique cellular pathways that involve forkhead transcription factors, sirtuins, protein kinase B (Akt), Bad, caspases, and poly (ADP-ribose) polymerase that may offer a fine line with determining cellular longevity, cell survival, and unwanted cancer progression. If one is cognizant of the these considerations, it becomes evident that nicotinamide holds great potential for multiple disease entities, but the development of new therapeutic strategies rests heavily upon the elucidation of the novel cellular pathways that nicotinamide closely governs.
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Affiliation(s)
- Kenneth Maiese
- Division of Cellular and Molecular Cerebral Ischemia, Wayne State University School of Medicine, Detroit, Michigan 48201, USA.
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