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Ponomareva D, Ivanov A, Bregestovski P. Analysis of the Effects of Pentose Phosphate Pathway Inhibition on the Generation of Reactive Oxygen Species and Epileptiform Activity in Hippocampal Slices. Int J Mol Sci 2024; 25:1934. [PMID: 38339211 PMCID: PMC10856462 DOI: 10.3390/ijms25031934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Revised: 01/27/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024] Open
Abstract
The pentose phosphate pathway (PPP) is one of three major pathways involved in glucose metabolism, which is regulated by glucose-6-phosphate dehydrogenase (G6PD) controls NADPH formation. NADPH, in turn, regulates the balance of oxidative stress and reactive oxygen species (ROS) levels. G6PD dysfunction, affecting the PPP, is implicated in neurological disorders, including epilepsy. However, PPP's role in epileptogenesis and ROS production during epileptic activity remains unclear. To clarify these points, we conducted electrophysiological and imaging analyses on mouse hippocampal brain slices. Using the specific G6PD inhibitor G6PDi-1, we assessed its effects on mouse hippocampal slices, examining intracellular ROS, glucose/oxygen consumption, the NAD(P)H level and ROS production during synaptic stimulation and in the 4AP epilepsy model. G6PDi-1 increased basal intracellular ROS levels and reduced synaptically induced glucose consumption but had no impact on baselevel of NAD(P)H and ROS production from synaptic stimulation. In the 4AP model, G6PDi-1 did not significantly alter spontaneous seizure frequency or H2O2 release amplitude but increased the frequency and peak amplitude of interictal events. These findings suggest that short-term PPP inhibition has a minimal impact on synaptic circuit activity.
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Affiliation(s)
- Daria Ponomareva
- Department of Physiology, Kazan State Medical University, 420012 Kazan, Russia;
- Institute of Neuroscience, Kazan State Medical University, 420012 Kazan, Russia
- INSERM, Institut de Neurosciences des Systèmes (INS), UMR1106, Aix-Marseille Université, 13005 Marseille, France;
| | - Anton Ivanov
- INSERM, Institut de Neurosciences des Systèmes (INS), UMR1106, Aix-Marseille Université, 13005 Marseille, France;
| | - Piotr Bregestovski
- Department of Physiology, Kazan State Medical University, 420012 Kazan, Russia;
- Institute of Neuroscience, Kazan State Medical University, 420012 Kazan, Russia
- INSERM, Institut de Neurosciences des Systèmes (INS), UMR1106, Aix-Marseille Université, 13005 Marseille, France;
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2
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Zilberter Y, Tabuena DR, Zilberter M. NOX-induced oxidative stress is a primary trigger of major neurodegenerative disorders. Prog Neurobiol 2023; 231:102539. [PMID: 37838279 DOI: 10.1016/j.pneurobio.2023.102539] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 10/10/2023] [Indexed: 10/16/2023]
Abstract
Neurodegenerative diseases (NDDs) causing cognitive impairment and dementia are difficult to treat due to the lack of understanding of primary initiating factors. Meanwhile, major sporadic NDDs share many risk factors and exhibit similar pathologies in their early stages, indicating the existence of common initiation pathways. Glucose hypometabolism associated with oxidative stress is one such primary, early and shared pathology, and a likely major cause of detrimental disease-associated cascades; targeting this common pathology may therefore be an effective preventative strategy for most sporadic NDDs. However, its exact cause and trigger remain unclear. Recent research suggests that early oxidative stress caused by NADPH oxidase (NOX) activation is a shared initiating mechanism among major sporadic NDDs and could prove to be the long-sought ubiquitous NDD trigger. We focus on two major NDDs - Alzheimer's disease (AD) and Parkinson's disease (PD), as well as on acquired epilepsy which is an increasingly recognized comorbidity in NDDs. We also discuss available data suggesting the relevance of the proposed mechanisms to other NDDs. We delve into the commonalities among these NDDs in neuroinflammation and NOX involvement to identify potential therapeutic targets and gain a deeper understanding of the underlying causes of NDDs.
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Affiliation(s)
- Yuri Zilberter
- Aix-Marseille Université, INSERM UMR1106, Institut de Neurosciences des Systèmes, Marseille, France
| | - Dennis R Tabuena
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA
| | - Misha Zilberter
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA.
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3
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Luo Y, Yang J, Zhang L, Tai Z, Huang H, Xu Z, Zhang H. Phosphoglycerate kinase (PGK) 1 succinylation modulates epileptic seizures and the blood-brain barrier. Exp Anim 2023; 72:475-489. [PMID: 37258131 PMCID: PMC10658094 DOI: 10.1538/expanim.23-0019] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 05/22/2023] [Indexed: 06/02/2023] Open
Abstract
Epilepsy is the most common chronic disorder in the nervous system, mainly characterized by recurrent, periodic, unpredictable seizures. Post-translational modifications (PTMs) are important protein functional regulators that regulate various physiological and pathological processes. It is significant for cell activity, stability, protein folding, and localization. Phosphoglycerate kinase (PGK) 1 has traditionally been studied as an important adenosine triphosphate (ATP)-generating enzyme of the glycolytic pathway. PGK1 catalyzes the reversible transfer of a phosphoryl group from 1, 3-bisphosphoglycerate (1, 3-BPG) to ADP, producing 3-phosphoglycerate (3-PG) and ATP. In addition to cell metabolism regulation, PGK1 is involved in multiple biological activities, including angiogenesis, autophagy, and DNA repair. However, the exact role of PGK1 succinylation in epilepsy has not been thoroughly investigated. The expression of PGK1 succinylation was analyzed by Immunoprecipitation. Western blots were used to assess the expression of PGK1, angiostatin, and vascular endothelial growth factor (VEGF) in a rat model of lithium-pilocarpine-induced acute epilepsy. Behavioral experiments were performed in a rat model of lithium-pilocarpine-induced acute epilepsy. ELISA method was used to measure the level of S100β in serum brain biomarkers' integrity of the blood-brain barrier. The expression of the succinylation of PGK1 was decreased in a rat model of lithium-pilocarpine-induced acute epilepsy compared with the normal rats in the hippocampus. Interestingly, the lysine 15 (K15), and the arginine (R) variants of lentivirus increased the susceptibility in a rat model of lithium-pilocarpine-induced acute epilepsy, and the K15 the glutamate (E) variants, had the opposite effect. In addition, the succinylation of PGK1 at K15 affected the expression of PGK1 succinylation but not the expression of PGK1total protein. Furthermore, the study found that the succinylation of PGK1 at K15 may affect the level of angiostatin and VEGF in the hippocampus, which also affects the level of S100β in serum. In conclusion, the mutation of the K15 site of PGK1 may alter the expression of the succinylation of PGK1 and then affect the integrity of the blood-brain barrier through the angiostatin / VEGF pathway altering the activity of epilepsy, which may be one of the new mechanisms of treatment strategies.
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Affiliation(s)
- Yuemei Luo
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi, Guizhou 563003, P.R. China
| | - Juan Yang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi, Guizhou 563003, P.R. China
| | - Lijia Zhang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi, Guizhou 563003, P.R. China
| | - Zhenzhen Tai
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi, Guizhou 563003, P.R. China
| | - Hao Huang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi, Guizhou 563003, P.R. China
| | - Zucai Xu
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi, Guizhou 563003, P.R. China
| | - Haiqing Zhang
- Department of Neurology, Affiliated Hospital of Zunyi Medical University, 149 Dalian Road, Zunyi, Guizhou 563003, P.R. China
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4
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Zhao W, Li M, Wang S, Li Z, Li H, Li S. CircRNA SRRM4 affects glucose metabolism by regulating PKM alternative splicing via SRSF3 deubiquitination in epilepsy. Neuropathol Appl Neurobiol 2023; 49:e12850. [PMID: 36168302 DOI: 10.1111/nan.12850] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 07/10/2022] [Accepted: 07/23/2022] [Indexed: 11/30/2022]
Abstract
OBJECTIVES Several reports suggest that epigenetic therapy may be a potential method for treating epilepsy, and circular RNAs (circRNAs) play important roles in mediating the epigenetic mechanisms associated with epilepsy; however, currently there are no effective treatment methods to prevent the progression of epileptogenesis. The circRNA serine/arginine repetitive matrix 4 (circSRRM4) was found to exert regulatory effects in temporal lobe epilepsy (TLE); however, the mechanisms involved are still unknown. MATERIALS AND METHODS To elucidate the molecular mechanism of circSRRM4, we investigated human epileptic brain tissue, epileptic rats, neuron and astrocyte cell lines using RT-qPCR, western blot, fluorescence in situ hybridisation, immunofluorescence staining, Nissl stain, micro-PET-CT, RNA-pulldown, liquid chromatography-mass spectrometry, and RBP immunoprecipitation techniques. Furthermore, we evaluated the pyruvate kinase M1/2 (PKM) expression patterns in the human and rat models of TLE. RESULTS We detected the increased circSRRM4 expression in the hypometabolic lesions of patients with TLE and discovered that circSrrm4 has specific spatiotemporal characteristics in rats with kainic acid-induced epilepsy. The decreased PKM1 expression and increased PKM2 expression were similar to the Warburg effect in tumours. Notably, circSrrm4 silencing reduced the incidence and frequency of epilepsy, improved local hypometabolism, and prevented neuronal loss and astrocyte activation. CONCLUSION PKM2 promotes lactic acid production in the astrocytes by inducing glycolysis, thereby contributing to the energy source for epileptic seizures. Notably, circSRRM4 combines with and inhibits serine and arginine rich splicing factor 3 (SRSF3) from joining the ubiquitin-proteasome pathway, improving the SRSF3-regulated alternative splicing of PKM, and consequently stimulating glycolysis in cells.
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Affiliation(s)
- Wujun Zhao
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China.,Department of Neurosurgery, The First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Miaomiao Li
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Shuai Wang
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Zhuang Li
- The Third Department of Neurosurgery, The People's Hospital of Liaoning Province, Shenyang, China
| | - Han Li
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
| | - Shaoyi Li
- Department of Neurosurgery, Shengjing Hospital of China Medical University, Shenyang, China
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5
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Affiliation(s)
- Gerald A. Dienel
- Department of Neurology University of Arkansas for Medical Sciences Little Rock Arkansas USA
- Department of Cell Biology and Physiology University of New Mexico School of Medicine Albuquerque New Mexico USA
| | - Lisa Gillinder
- Mater Hospital South Brisbane Queensland Australia
- Faculty of Medicine Mater Research Institute, University of Queensland St Lucia Queensland Australia
| | - Aileen McGonigal
- Mater Hospital South Brisbane Queensland Australia
- Faculty of Medicine Mater Research Institute, University of Queensland St Lucia Queensland Australia
| | - Karin Borges
- Faculty of Medicine School of Biomedical Sciences, University of Queensland St Lucia Queensland Australia
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6
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Dienel GA, Gillinder L, McGonigal A, Borges K. Potential new roles for glycogen in epilepsy. Epilepsia 2023; 64:29-53. [PMID: 36117414 PMCID: PMC10952408 DOI: 10.1111/epi.17412] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/15/2022] [Accepted: 09/15/2022] [Indexed: 01/21/2023]
Abstract
Seizures often originate in epileptogenic foci. Between seizures (interictally), these foci and some of the surrounding tissue often show low signals with 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) in many epileptic patients, even when there are no radiologically detectable structural abnormalities. Low FDG-PET signals are thought to reflect glucose hypometabolism. Here, we review knowledge about metabolism of glucose and glycogen and oxidative stress in people with epilepsy and in acute and chronic rodent seizure models. Interictal brain glucose levels are normal and do not cause apparent glucose hypometabolism, which remains unexplained. During seizures, high amounts of fuel are needed to satisfy increased energy demands. Astrocytes consume glycogen as an additional emergency fuel to supplement glucose during high metabolic demand, such as during brain stimulation, stress, and seizures. In rodents, brain glycogen levels drop during induced seizures and increase to higher levels thereafter. Interictally, in people with epilepsy and in chronic epilepsy models, normal glucose but high glycogen levels have been found in the presumed brain areas involved in seizure generation. We present our new hypothesis that as an adaptive response to repeated episodes of high metabolic demand, high interictal glycogen levels in epileptogenic brain areas are used to support energy metabolism and potentially interictal neuronal activity. Glycogenolysis, which can be triggered by stress or oxidative stress, leads to decreased utilization of plasma glucose in epileptogenic brain areas, resulting in low FDG signals that are related to functional changes underlying seizure onset and propagation. This is (partially) reversible after successful surgery. Last, we propose that potential interictal glycogen depletion in epileptogenic and surrounding areas may cause energy shortages in astrocytes, which may impair potassium buffering and contribute to seizure generation. Based on these hypotheses, auxiliary fuels or treatments that support glycogen metabolism may be useful to treat epilepsy.
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Affiliation(s)
- Gerald A. Dienel
- Department of NeurologyUniversity of Arkansas for Medical SciencesLittle RockArkansasUSA
- Department of Cell Biology and PhysiologyUniversity of New Mexico School of MedicineAlbuquerqueNew MexicoUSA
| | - Lisa Gillinder
- Mater HospitalSouth BrisbaneQueenslandAustralia
- Faculty of MedicineMater Research Institute, University of QueenslandSt LuciaQueenslandAustralia
| | - Aileen McGonigal
- Mater HospitalSouth BrisbaneQueenslandAustralia
- Faculty of MedicineMater Research Institute, University of QueenslandSt LuciaQueenslandAustralia
| | - Karin Borges
- Faculty of MedicineSchool of Biomedical Sciences, University of QueenslandSt LuciaQueenslandAustralia
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7
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Fabisiak T, Patel M. Crosstalk between neuroinflammation and oxidative stress in epilepsy. Front Cell Dev Biol 2022; 10:976953. [PMID: 36035987 PMCID: PMC9399352 DOI: 10.3389/fcell.2022.976953] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 07/18/2022] [Indexed: 11/24/2022] Open
Abstract
The roles of both neuroinflammation and oxidative stress in the pathophysiology of epilepsy have begun to receive considerable attention in recent years. However, these concepts are predominantly studied as separate entities despite the evidence that neuroinflammatory and redox-based signaling cascades have significant crosstalk. Oxidative post-translational modifications have been demonstrated to directly influence the function of key neuroinflammatory mediators. Neuroinflammation can further be controlled on the transcriptional level as the transcriptional regulators NF-KB and nrf2 are activated by reactive oxygen species. Further, neuroinflammation can induce the increased expression and activity of NADPH oxidase, leading to a highly oxidative environment. These factors additionally influence mitochondria function and the metabolic status of neurons and glia, which are already metabolically stressed in epilepsy. Given the implication of this relationship to disease pathology, this review explores the numerous mechanisms by which neuroinflammation and oxidative stress influence one another in the context of epilepsy. We further examine the efficacy of treatments targeting oxidative stress and redox regulation in animal and human epilepsies in the literature that warrant further investigation. Treatment approaches aimed at rectifying oxidative stress and aberrant redox signaling may enable control of neuroinflammation and improve patient outcomes.
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8
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Daněk J, Danačíková Š, Kala D, Svoboda J, Kapoor S, Pošusta A, Folbergrová J, Tauchmannová K, Mráček T, Otáhal J. Sulforaphane Ameliorates Metabolic Changes Associated With Status Epilepticus in Immature Rats. Front Cell Neurosci 2022; 16:855161. [PMID: 35370554 PMCID: PMC8965559 DOI: 10.3389/fncel.2022.855161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 02/16/2022] [Indexed: 11/24/2022] Open
Abstract
Status epilepticus (SE) is a common paediatric emergency with the highest incidence in the neonatal period and is a well-known epileptogenic insult. As previously established in various experimental and human studies, SE induces long-term alterations to brain metabolism, alterations that directly contribute to the development of epilepsy. To influence these changes, organic isothiocyanate compound sulforaphane (SFN) has been used in the present study for its known effect of enhancing antioxidative, cytoprotective, and metabolic cellular properties via the Nrf2 pathway. We have explored the effect of SFN in a model of acquired epilepsy induced by Li-Cl pilocarpine in immature rats (12 days old). Energy metabolites PCr, ATP, glucose, glycogen, and lactate were determined by enzymatic fluorimetric methods during the acute phase of SE. Protein expression was evaluated by Western blot (WB) analysis. Neuronal death was scored on the FluoroJadeB stained brain sections harvested 24 h after SE. To assess the effect of SFN on glucose metabolism we have performed a series of 18F-DG μCT/PET recordings 1 h, 1 day, and 3 weeks after the induction of SE. Responses of cerebral blood flow (CBF) to electrical stimulation and their influence by SFN were evaluated by laser Doppler flowmetry (LDF). We have demonstrated that the Nrf2 pathway is upregulated in the CNS of immature rats after SFN treatment. In the animals that had undergone SE, SFN was responsible for lowering glucose uptake in most regions 1 h after the induction of SE. Moreover, SFN partially reversed hypometabolism observed after 24 h and achieved full reversal at approximately 3 weeks after SE. Since no difference in cell death was observed in SFN treated group, these changes cannot be attributed to differences in neurodegeneration. SFN per se did not affect the glucose uptake at any given time point suggesting that SFN improves endogenous CNS ability to adapt to the epileptogenic insult. Furthermore, we had discovered that SFN improves blood flow and accelerates CBF response to electrical stimulation. Our findings suggest that SFN improves metabolic changes induced by SE which have been identified during epileptogenesis in various animal models of acquired epilepsy.
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Affiliation(s)
- Jan Daněk
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Šárka Danačíková
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - David Kala
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Jan Svoboda
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
- Department of Pathophysiology, Second Faculty of Medicine, Charles University, Prague, Czechia
| | - Sonam Kapoor
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Antonín Pošusta
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | | | | | - Tomáš Mráček
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
| | - Jakub Otáhal
- Institute of Physiology, Czech Academy of Sciences, Prague, Czechia
- Department of Pathophysiology, Second Faculty of Medicine, Charles University, Prague, Czechia
- *Correspondence: Jakub Otáhal,
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9
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Poff AM, Moss S, Soliven M, D'Agostino DP. Ketone Supplementation: Meeting the Needs of the Brain in an Energy Crisis. Front Nutr 2022; 8:783659. [PMID: 35004814 PMCID: PMC8734638 DOI: 10.3389/fnut.2021.783659] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 12/03/2021] [Indexed: 12/11/2022] Open
Abstract
Diverse neurological disorders are associated with a deficit in brain energy metabolism, often characterized by acute or chronic glucose hypometabolism. Ketones serve as the brain's only significant alternative fuel and can even become the primary fuel in conditions of limited glucose availability. Thus, dietary supplementation with exogenous ketones represents a promising novel therapeutic strategy to help meet the energetic needs of the brain in an energy crisis. Preliminary evidence suggests ketosis induced by exogenous ketones may attenuate damage or improve cognitive and motor performance in neurological conditions such as seizure disorders, mild cognitive impairment, Alzheimer's disease, and neurotrauma.
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Affiliation(s)
- Angela M Poff
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Sara Moss
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Maricel Soliven
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
| | - Dominic P D'Agostino
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, United States
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10
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Unifying mechanism behind the onset of acquired epilepsy. Trends Pharmacol Sci 2021; 43:87-96. [PMID: 34887128 DOI: 10.1016/j.tips.2021.11.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/08/2021] [Accepted: 11/09/2021] [Indexed: 12/15/2022]
Abstract
Acquired epilepsy (AE) can result from a number of brain insults and neurological diseases with wide etiological diversity sharing one common outcome of brain epileptiform activity. This implies that despite their disparity, all these initiating pathologies affect the same fundamental brain functions underlying network excitability. Identifying such mechanisms and their availability as therapeutic targets would help develop an effective strategy for epileptogenesis prevention. In this opinion article, we propose that the vicious cycle of NADPH oxidase (NOX)-mediated oxidative stress and glucose hypometabolism is the underlying cause of AE, as available data reveal a critical role for both pathologies in epileptogenesis and the process of seizure initiation. Altogether, here we present a novel view on the mechanisms behind the onset of AE and identify therapeutic targets for potential clinical applications.
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11
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Malkov A, Popova I, Ivanov A, Jang SS, Yoon SY, Osypov A, Huang Y, Zilberter Y, Zilberter M. Aβ initiates brain hypometabolism, network dysfunction and behavioral abnormalities via NOX2-induced oxidative stress in mice. Commun Biol 2021; 4:1054. [PMID: 34504272 PMCID: PMC8429759 DOI: 10.1038/s42003-021-02551-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 08/12/2021] [Indexed: 12/30/2022] Open
Abstract
A predominant trigger and driver of sporadic Alzheimer’s disease (AD) is the synergy of brain oxidative stress and glucose hypometabolism starting at early preclinical stages. Oxidative stress damages macromolecules, while glucose hypometabolism impairs cellular energy supply and antioxidant defense. However, the exact cause of AD-associated glucose hypometabolism and its network consequences have remained unknown. Here we report NADPH oxidase 2 (NOX2) activation as the main initiating mechanism behind Aβ1-42-related glucose hypometabolism and network dysfunction. We utilize a combination of electrophysiology with real-time recordings of metabolic transients both ex- and in-vivo to show that Aβ1-42 induces oxidative stress and acutely reduces cellular glucose consumption followed by long-lasting network hyperactivity and abnormalities in the animal behavioral profile. Critically, all of these pathological changes were prevented by the novel bioavailable NOX2 antagonist GSK2795039. Our data provide direct experimental evidence for causes and consequences of AD-related brain glucose hypometabolism, and suggest that targeting NOX2-mediated oxidative stress is a promising approach to both the prevention and treatment of AD. Anton Malkov, Irina Popova et al. demonstrate that beta-amyloid application induces oxidative stress and reduces glucose consumption in the mouse brain, leading to network hyperactivity and behavioral changes—pathologies similar to those observed early on in Alzheimer’s disease patients. Inhibition of NADPH oxidase 2 (NOX2) rescued these phenotypes, suggesting that NOX2 may represent an important therapeutic target for Alzheimer’s disease.
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Affiliation(s)
- Anton Malkov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - Irina Popova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - Anton Ivanov
- Aix Marseille Université, Inserm, Marseille, France
| | - Sung-Soo Jang
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA
| | - Seo Yeon Yoon
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA
| | - Alexander Osypov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russia.,Institute of Higher Nervous Activity and Neurophysiology, Russian Academy of Sciences, Moscow, Russia
| | - Yadong Huang
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA.,Department of Neurology, University of California, San Francisco, CA, USA
| | | | - Misha Zilberter
- Gladstone Institute of Neurological Disease, San Francisco, CA, USA.
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12
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Jiang G, Wang S, Chen M, Ding X, He W, Wang L, Wang S, Yu J, Wang X. Linsitinib (OSI-906) modulates brain energy metabolism and seizure activity in the lithium-pilocarpine rat model. ACTA EPILEPTOLOGICA 2021. [DOI: 10.1186/s42494-021-00054-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Epileptic seizure is a process of energy accumulation, bursting, and depletion accompanied by the production, spread, and termination of epileptic discharges. The energy required for a seizure is mainly provided through mitochondrial production of ATP. Mitochondrial diseases often lead to epileptic seizures, and energy depletion caused by seizures can lead to mitochondrial dysfunction. The energy metabolism has become a key target for treatment of epileptic diseases.
Method
The effect of OSI-906, an insulin receptor (IR)/ insulin-like growth factor 1 receptor (IGF-1R) inhibitor, on behaviors and electroencephalographic activity in the lithium-pilocarpine rats were tested. 18F-FDG positron emission tomography (PET)/ computed tomography (CT) was performed to detect the relative whole-brain glucose uptake values. Electron microscopy was performed to observe the ultrastructure of neuronal and mitochondrial damage. The changes in blood glucose at different time points before and after the intervention were tested and the effects of OSI-906 on IR/IGF-1R and downstream Akt signaling in the context of seizures were evaluated.
Results
The OSI-906 treatment applied 3 days before the pilocarpine-induced seizures significantly reduced the seizure severity, prolonged the seizure latency and decreased the EEG energy density. MicroPET/CT revealed that 50 mg/kg of OSI-906 inhibited the 18F-FDG glucose uptake after epileptic seizures, suggesting that OSI-906, through inhibiting IR/IGF-1R and the downstream AKT signaling, may regulate the excessive energy consumption of the epileptic brain. The OSI-906 treatment also reduced the mitochondrial damage caused by epileptic seizures.
Conclusion
The IR/IGF-1R inhibitor OSI-906 can significantly reduce the sensitivity and severity of pilocarpine-induced seizures by inhibiting the IR/IGF-1R and the downstream Akt signaling pathway.
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13
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Berk BA, Packer RMA, Law TH, Wessmann A, Bathen-Nöthen A, Jokinen TS, Knebel A, Tipold A, Pelligand L, Volk HA. Medium-chain triglycerides dietary supplement improves cognitive abilities in canine epilepsy. Epilepsy Behav 2021; 114:107608. [PMID: 33268017 DOI: 10.1016/j.yebeh.2020.107608] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Revised: 10/08/2020] [Accepted: 10/27/2020] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Cognitive impairments (CI) have recently been identified in canine epilepsy patients. A medium-chain triglyceride (MCT) enriched diet has been demonstrated to improve cognition in aged dogs and seizure control in canine epilepsy. This study evaluates the short-term effects of MCT-oil consumption on cognitive abilities in dogs with epilepsy, a naturally occurring animal model. METHODS A 6-month multicenter, prospective, randomized, double-blinded, controlled cross-over diet trial was conducted comparing dietary supplementation (DS) of MCT oil to a control oil. Allocation to dietary oil supplements, consisting of 9% total caloric intake, was block-randomized and supplemented into each dogs' diet for 3 months followed by a respective switch of DS-oil for a further 3 months. Noninvasive cognitive tests and a validated psychometric tool were utilized to evaluate cognitive function and perturbations associated with dietary intervention. RESULTS Twenty-nine dogs completed the trial, of which 18 completed noninvasive cognitive testing. Spatial-working memory (P = 0.008), problem-solving ability (P = 0.048), and owner-reported trainability (P = 0.041) were significantly improved during MCT-oil supplementation compared to control-DS. SIGNIFICANCE MCT-oil DS improves cognition in dogs with epilepsy when compared to a control-DS. MCT supplementation may represent a promising option to address CI associated with epilepsy.
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Affiliation(s)
- Benjamin Andreas Berk
- Royal Veterinary College, Department of Clinical Science and Services, Hatfield, United Kingdom; BrainCheck.Pet - Tierärztliche Praxis für Epilepsie, Sachsenstraße, Mannheim, Germany.
| | - Rowena Mary Anne Packer
- Royal Veterinary College, Department of Clinical Science and Services, Hatfield, United Kingdom
| | - Tsz Hong Law
- Royal Veterinary College, Department of Clinical Science and Services, Hatfield, United Kingdom
| | - Annette Wessmann
- Pride Veterinary Centre, Riverside Road, Pride Park, Derby, United Kingdom
| | | | - Tarja Susanna Jokinen
- Faculty of Veterinary Medicine, Dep. of Equine and Small Animal Medicine, Helsinki, Finland
| | - Anna Knebel
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
| | - Andrea Tipold
- Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
| | - Ludovic Pelligand
- Royal Veterinary College, Department of Comparative Biomedical Sciences, Hatfield, United Kingdom
| | - Holger Andreas Volk
- Royal Veterinary College, Department of Clinical Science and Services, Hatfield, United Kingdom; Department of Small Animal Medicine and Surgery, University of Veterinary Medicine, Hannover, Germany
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14
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Peng W, Liu X, Tan C, Zhou W, Jiang J, Zhou X, Du J, Mo L, Chen L. Zinc-α2-glycoprotein relieved seizure-Induced neuronal glucose uptake impairment via insulin-like growth factor 1 receptor-regulated glucose transporter 3 expression. J Neurochem 2020; 157:695-709. [PMID: 33258143 DOI: 10.1111/jnc.15254] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 10/30/2020] [Accepted: 11/19/2020] [Indexed: 12/14/2022]
Abstract
Glucose hypometabolism is observed in epilepsy and promotes epileptogenesis. Glucose hypometabolism in epilepsy may be attributed to decreased neuronal glucose uptake, but its molecular mechanism remains unclear. Zinc-α2-glycoprotein (ZAG) is related to glucose metabolism and is reported to suppress seizures. The anti-epileptic effect of ZAG may be attributed to its regulation of neuronal glucose metabolism. This study explored the effect of ZAG on neuronal glucose uptake and its molecular mechanism via insulin-like growth factor 1 receptor (IGF1R)-regulated glucose transporter 3 (GLUT-3) expression. The ZAG level was modulated by lentivirus in primary culture neurons. Neuronal seizure models were induced by Mg2+ -free artificial cerebrospinal fluid. We assessed neuronal glucose uptake by the 2-NBDG method and Glucose Uptake Colorimetric Assay Kit. IGF1R was activated by IGF1 and blocked by AXL1717. The expression and distribution of IGF1R and GLUT-3, together with IGF1R phosphorylation, were measured by western blot. The binding between ZAG and IGF1R was determined by coimmunoprecipitation. Neuronal glucose uptake and GLUT-3 expression were significantly decreased by seizure or ZAG knockdown, whereas ZAG over-expression or IGF1 treatment reversed this decrease. The effect of ZAG on neuronal glucose uptake and GLUT-3 expression was blocked by AXL1717. ZAG increased IGF1R distribution and phosphorylation possibly by binding. Additionally, IGF1R increased GLUT-3 activity by increasing GLUT-3 expression. In epilepsy/seizure, neuronal glucose uptake suppression may be attributed to a decrease in ZAG, which suppresses neuronal GLUT-3 expression by regulating the activity of IGF1R. ZAG, IGF1R, and GLUT-3 may be novel potential therapeutic targets of glucose hypometabolism in epilepsy and seizures.
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Affiliation(s)
- Wuxue Peng
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xi Liu
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Changhong Tan
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Wen Zhou
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jin Jiang
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xuan Zhou
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Juncong Du
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lijuan Mo
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lifen Chen
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
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15
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Zilberter Y, Zilberter T. Glucose-Sparing Action of Ketones Boosts Functions Exclusive to Glucose in the Brain. eNeuro 2020; 7:ENEURO.0303-20.2020. [PMID: 33168619 PMCID: PMC7768283 DOI: 10.1523/eneuro.0303-20.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 12/22/2022] Open
Abstract
The ketogenic diet (KD) has been successfully used for a century for treating refractory epilepsy and is currently seen as one of the few viable approaches to the treatment of a plethora of metabolic and neurodegenerative diseases. Empirical evidence notwithstanding, there is still no universal understanding of KD mechanism(s). An important fact is that the brain is capable of using ketone bodies for fuel. Another critical point is that glucose's functions span beyond its role as an energy substrate, and in most of these functions, glucose is irreplaceable. By acting as a supplementary fuel, ketone bodies may free up glucose for its other crucial and exclusive function. We propose that this glucose-sparing effect of ketone bodies may underlie the effectiveness of KD in epilepsy and major neurodegenerative diseases, which are all characterized by brain glucose hypometabolism.
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Affiliation(s)
- Yuri Zilberter
- Institut de Neurosciences des Systèmes, Aix-Marseille Universite, Institut National de la Santé et de la Recherche Médicale Unité Mixte de Recherche 1106, Marseille 13385, France
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, 142290, Pushchino, Russia
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16
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Malkov A, Ivanov AI, Latyshkova A, Bregestovski P, Zilberter M, Zilberter Y. Activation of nicotinamide adenine dinucleotide phosphate oxidase is the primary trigger of epileptic seizures in rodent models. Ann Neurol 2019; 85:907-920. [PMID: 30937971 DOI: 10.1002/ana.25474] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 03/05/2019] [Accepted: 03/31/2019] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Despite decades of epilepsy research, 30% of focal epilepsies remain resistant to antiseizure drugs, with effective drug development impeded by lack of understanding on how seizures are initiated. Here, we report the mechanism of seizure onset relevant to most seizures that are characteristic of focal epilepsies. METHODS Electric and metabolic network parameters were measured using several seizure models in mouse hippocampal slices and acutely induced seizures in rats in vivo to determine metabolic events occurring at seizure onset. RESULTS We show that seizure onset is associated with a rapid release of H2 O2 resulting from N-methyl-D-aspartate (NMDA) receptor-mediated activation of nicotinamide adenine dinucleotide phosphate oxidase (NOX). NOX blockade prevented the fast H2 O2 release as well as the direct current shift and seizurelike event induction in slices. Similarly, intracerebroventricular injection of NOX antagonists prevented acutely induced seizures in rats. INTERPRETATION Our results show that seizures are initiated by NMDA receptor-mediated NOX-induced oxidative stress and can be arrested by NOX inhibition. We introduce a novel use for blood-brain barrier-permeable NOX inhibitor with a significant potential to become the first seizure-specific medication. Thus, targeting NOX may provide a breakthrough treatment for focal epilepsies. ANN NEUROL 2019;85:907-920.
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Affiliation(s)
- Anton Malkov
- Aix-Marseille University, National Institute of Health and Medical Research, Institute of Neuroscience Systems, Mixed Unit of Research 1106, Marseille, France.,Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - Anton I Ivanov
- Aix-Marseille University, National Institute of Health and Medical Research, Institute of Neuroscience Systems, Mixed Unit of Research 1106, Marseille, France
| | - Alexandra Latyshkova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Russia
| | - Piotr Bregestovski
- Aix-Marseille University, National Institute of Health and Medical Research, Institute of Neuroscience Systems, Mixed Unit of Research 1106, Marseille, France.,Institute of Neurosciences, Kazan State Medical University, Kazan, Russia
| | - Misha Zilberter
- Gladstone Institute of Neurological Disease, San Francisco, CA
| | - Yuri Zilberter
- Aix-Marseille University, National Institute of Health and Medical Research, Institute of Neuroscience Systems, Mixed Unit of Research 1106, Marseille, France
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17
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Issa Roach AT, Pizarro D, Deshpande HD, Pati S, Szaflarski JP, Riley KO, Muhlhofer W, Houston T. Ictogenesis during sEEG evaluation after acute intracranial hemorrhage. EPILEPSY & BEHAVIOR CASE REPORTS 2019; 11:115-119. [PMID: 30963027 PMCID: PMC6434162 DOI: 10.1016/j.ebcr.2019.02.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 02/12/2019] [Accepted: 02/26/2019] [Indexed: 11/09/2022]
Abstract
We present a unique case of a patient with drug-resistant focal epilepsy undergoing stereoelectroencephalography (sEEG) who developed an acute posttraumatic intracranial hemorrhage during monitoring, first detected by changes on sEEG. Our case demonstrates the evolution of electrographic changes at the time of initial hemorrhage to the development of ictal activity. We conducted spectral analysis of the sEEG data to illustrate the transition from an interictal to ictal state. Initially, delta power increased in the region of acute hemorrhage, followed by sustained regional reduction in frequency variability. Our findings provide further information on the development of epileptiform activity in acute hemorrhage. sEEG shows new epileptiform activity in acute hemorrhage despite lack of clinical signs. In acute hemorrhage, there is initially an increase in delta power. There is loss of frequency variability in involved channels in acute hemorrhage.
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Affiliation(s)
- Alexandra T Issa Roach
- Department of Neurology, University of Alabama at Birmingham, AL, United States of America
| | - Diana Pizarro
- Department of Neurology, University of Alabama at Birmingham, AL, United States of America
| | - Hrishikesh D Deshpande
- Department of Neurology, University of Alabama at Birmingham, AL, United States of America
| | - Sandipan Pati
- Department of Neurology, University of Alabama at Birmingham, AL, United States of America
| | - Jerzy P Szaflarski
- Department of Neurology, University of Alabama at Birmingham, AL, United States of America
| | - Kristen O Riley
- Department of Neurosurgery, University of Alabama at Birmingham, AL, United States of America
| | - Wolfgang Muhlhofer
- Department of Neurology, University of Alabama at Birmingham, AL, United States of America
| | - Thomas Houston
- Department of Neurology, University of Alabama at Birmingham, AL, United States of America
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18
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Tang Y, Liow JS, Zhang Z, Li J, Long T, Li Y, Tang B, Hu S. The Evaluation of Dynamic FDG-PET for Detecting Epileptic Foci and Analyzing Reduced Glucose Phosphorylation in Refractory Epilepsy. Front Neurosci 2019; 12:993. [PMID: 30686968 PMCID: PMC6333859 DOI: 10.3389/fnins.2018.00993] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 12/11/2018] [Indexed: 12/15/2022] Open
Abstract
Aims: Static fluorodeoxyglucose (FDG)-positron emission tomographic (PET) imaging plays an important role in the localization of epileptic foci. Dynamic FDG PET allows calculation of kinetic parameters. The aim of this study was to investigate whether kinetic parameters have potential for identifying epileptic foci, and to assess the correlation of parameters asymmetry indexes (ASYM) between dynamic and static FDG PET for understanding the pathophysiology of hypometabolism within intractable epilepsy. Methods: Seventeen patients who had refractory epilepsy correctly localized by static FDG PET with good outcome after foci resection were included. Eight controls were also studied. We performed dynamic and static FDG PET scan before operation. Images of both scans were coregistered to the montreal neurological institute space, regional time activity curves and activity concentration (AC) were obtained by applying the automated anatomical labeling template to the two spatially normalized images, respectively. Kinetic parameters were obtained using a two-tissue non-reversible compartmental model with an image-derived input function. AC from the static scan was used. Side-to-side ASYM of both static AC and kinetic parameters were calculated and analyzed in the hypometabolic epileptogenic regions and non-epileptogenic regions. Results: Higher values of ASYM from both kinetic parameters and static AC were found in the patients compared to the controls from epileptogenic regions. In the non-epileptogenic regions, no ASYM differences were seen between patients and controls for all parameters. In patients, static AC showed larger ASYM than influx (K1) and efflux (k2) of capillaries, but there were no statistical differences of ASYM between net metabolic flux (Ki) or the phosphorylation (k3) and static AC. ASYM of static AC positively correlated with ASYM of k3. Conclusion: Dynamic FDG PET can provide equally effective in detecting the epileptic foci compared to static FDG PET in this small cohort. In addition, compared to capillary influx, the hypometabolism of epileptic foci may be related to reduced glucose phosphorylation.
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Affiliation(s)
- Yongxiang Tang
- Department of PET Center, Xiangya Hospital Central South University, Changsha, China
| | - Jeih-San Liow
- Molecular Imaging Branch, National Institute of Mental Health, Bethesda, MD, United States
| | - Zhimin Zhang
- Department of Blood Transfusion, Xiangya Hospital Central South University, Changsha, China
| | - Jian Li
- Department of PET Center, Xiangya Hospital Central South University, Changsha, China
| | - Tingting Long
- Department of PET Center, Xiangya Hospital Central South University, Changsha, China
| | - Yulai Li
- Department of PET Center, Xiangya Hospital Central South University, Changsha, China
| | - Beisha Tang
- National Clinical Research Center for Geriatric Diseases, Xiangya Hospital Central South University, Changsha, China
| | - Shuo Hu
- Department of PET Center, Xiangya Hospital Central South University, Changsha, China.,National Clinical Research Center for Geriatric Diseases, Xiangya Hospital Central South University, Changsha, China
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19
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McDonald T, Puchowicz M, Borges K. Impairments in Oxidative Glucose Metabolism in Epilepsy and Metabolic Treatments Thereof. Front Cell Neurosci 2018; 12:274. [PMID: 30233320 PMCID: PMC6127311 DOI: 10.3389/fncel.2018.00274] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 08/06/2018] [Indexed: 12/19/2022] Open
Abstract
There is mounting evidence that oxidative glucose metabolism is impaired in epilepsy and recent work has further characterized the metabolic mechanisms involved. In healthy people eating a traditional diet, including carbohydrates, fats and protein, the major energy substrate in brain is glucose. Cytosolic glucose metabolism generates small amounts of energy, but oxidative glucose metabolism in the mitochondria generates most ATP, in addition to biosynthetic precursors in cells. Energy is crucial for the brain to signal "normally," while loss of energy can contribute to seizure generation by destabilizing membrane potentials and signaling in the chronic epileptic brain. Here we summarize the known biochemical mechanisms that contribute to the disturbance in oxidative glucose metabolism in epilepsy, including decreases in glucose transport, reduced activity of particular steps in the oxidative metabolism of glucose such as pyruvate dehydrogenase activity, and increased anaplerotic need. This knowledge justifies the use of alternative brain fuels as sources of energy, such as ketones, TCA cycle intermediates and precursors as well as even medium chain fatty acids and triheptanoin.
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Affiliation(s)
- Tanya McDonald
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia
| | - Michelle Puchowicz
- Department of Nutrition, School of Medicine, Case Western Reserve University, Cleveland, OH, United States
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Karin Borges
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia
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