1
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Newman M, Lynch C, Connery H, Goldsmith W, Nurkiewicz T, Raylman R, Boyd J. Fentanyl overdose: Temporal effects and prognostic factors in SKH1 mice. Basic Clin Pharmacol Toxicol 2024; 134:460-471. [PMID: 38284460 PMCID: PMC10939806 DOI: 10.1111/bcpt.13984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 01/09/2024] [Accepted: 01/12/2024] [Indexed: 01/30/2024]
Abstract
Fentanyl exposure and overdose are growing concerns in public health and occupational safety. This study aimed to establish parameters of fentanyl lethality in SKH1 mice for future overdose research. Lethality was determined using the up-down procedure, with subjects monitored post-administration using pulse oximetry (5 min) and then whole-body plethysmography (40 min). Following the determination of subcutaneous dose-response, [18F]Fluorodeoxyglucose positron emission tomography (18 F-FDG PET) was performed after LD10 fentanyl at 40 min, 6 h, 24 h or 7 days post-dose. LD10 and LD50 were observed to be 110 and 135 mg/kg, respectively, and consistent with four-parameter logistic fit values of 111.2 and 134.6 mg/kg (r2 = 0.9996). Overdose (LD10 or greater) yielded three distinct cardiovascular groups: survival, non-survival with blood oxygen saturation (SpO2) minimum ≥37% and non-survival with SpO2 <37%. Breaths per minute, minute volume and inspiratory quotient were significantly different between surviving and non-surviving animals for up to 40 min post-injection. 18 F-FDG PET revealed decreased glucose uptake in the heart, lungs and brain for up to 24 h. These findings provide critical insights into fentanyl lethality in SKH1 mice, including non-invasive respiratory effects and organ-specific impacts that are invaluable for future translational studies investigating the temporal effects of fentanyl overdose.
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Affiliation(s)
- Mackenzie Newman
- Department of Orthopaedic Surgery, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA
- Department of Orthopaedics, West Virginia University School of Medicine, Morgantown, West Virginia, USA
| | - Cayla Lynch
- Department of Physiology, Pharmacology and Toxicology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV, USA
| | - Heather Connery
- Department of Physiology, Pharmacology and Toxicology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV, USA
| | - William Goldsmith
- Department of Physiology, Pharmacology and Toxicology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV, USA
- Center for Inhalation Toxicology (iTOX), West Virginia University School of Medicine, Morgantown, WV, USA
| | - Timothy Nurkiewicz
- Department of Physiology, Pharmacology and Toxicology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV, USA
- Center for Inhalation Toxicology (iTOX), West Virginia University School of Medicine, Morgantown, WV, USA
| | - Raymond Raylman
- Department of Radiology, West Virginia University School of Medicine, Morgantown, WV, USA
| | - Jonathan Boyd
- Department of Orthopaedic Surgery, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA
- Department of Orthopaedics, West Virginia University School of Medicine, Morgantown, West Virginia, USA
- Department of Physiology, Pharmacology and Toxicology, Robert C. Byrd Health Sciences Center, West Virginia University, Morgantown, WV, USA
- Center for Inhalation Toxicology (iTOX), West Virginia University School of Medicine, Morgantown, WV, USA
- Department of Pharmacology and Toxicology, Virginia Commonwealth University School of Medicine, Richmond, Virginia, USA
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2
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Méndez-Flores OG, Hernández-Kelly LC, Olivares-Bañuelos TN, López-Ramírez G, Ortega A. Brain energetics and glucose transport in metabolic diseases: role in neurodegeneration. Nutr Neurosci 2024:1-12. [PMID: 38294500 DOI: 10.1080/1028415x.2024.2306427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
OBJECTIVES Neurons and glial cells are the main functional and structural elements of the brain, and the former depends on the latter for their nutritional, functional and structural organization, as well as for their energy maintenance. METHODS Glucose is the main metabolic source that fulfills energetic demands, either by direct anaplerosis or through its conversion to metabolic intermediates. Development of some neurodegenerative diseases have been related with modifications in the expression and/or function of glial glucose transporters, which might cause physiological and/or pathological disturbances of brain metabolism. In the present contribution, we summarized the experimental findings that describe the exquisite adjustment in expression and function of glial glucose transporters from physiologic to pathologic metabolism, and its relevance to neurodegenerative diseases. RESULTS A exhaustive literature review was done in order to gain insight into the role of brain energetics in neurodegenerative disease. This study made evident a critical involvement of glucose transporters and thus brain energetics in the development of neurodegenerative diseases. DISCUSSION An exquisite adjustment in the expression and function of glial glucose transporters from physiologic to pathologic metabolism is a biochemical signature of neurodegenerative diseases.
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Affiliation(s)
- Orquídea G Méndez-Flores
- División Académica de Ciencias de la Salud, Universidad Juárez Autónoma de Tabasco (UJAT), Villahermosa, México
| | - Luisa C Hernández-Kelly
- Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México, México
| | | | - Gabriel López-Ramírez
- División Académica de Ciencias de la Salud, Universidad Juárez Autónoma de Tabasco (UJAT), Villahermosa, México
| | - Arturo Ortega
- Laboratorio de Neurotoxicología, Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Ciudad de México, México
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3
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Li X, Hu S, Cai Y, Liu X, Luo J, Wu T. Revving the engine: PKB/AKT as a key regulator of cellular glucose metabolism. Front Physiol 2024; 14:1320964. [PMID: 38264327 PMCID: PMC10804622 DOI: 10.3389/fphys.2023.1320964] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 12/12/2023] [Indexed: 01/25/2024] Open
Abstract
Glucose metabolism is of critical importance for cell growth and proliferation, the disorders of which have been widely implicated in cancer progression. Glucose uptake is achieved differently by normal cells and cancer cells. Even in an aerobic environment, cancer cells tend to undergo metabolism through glycolysis rather than the oxidative phosphorylation pathway. Disordered metabolic syndrome is characterized by elevated levels of metabolites that can cause changes in the tumor microenvironment, thereby promoting tumor recurrence and metastasis. The activation of glycolysis-related proteins and transcription factors is involved in the regulation of cellular glucose metabolism. Changes in glucose metabolism activity are closely related to activation of protein kinase B (PKB/AKT). This review discusses recent findings on the regulation of glucose metabolism by AKT in tumors. Furthermore, the review summarizes the potential importance of AKT in the regulation of each process throughout glucose metabolism to provide a theoretical basis for AKT as a target for cancers.
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Affiliation(s)
- Xia Li
- General Practice Medical Center, West China Hospital, Sichuan University, Chengdu, China
| | - Shuying Hu
- General Practice Medical Center, West China Hospital, Sichuan University, Chengdu, China
| | - Yaoting Cai
- General Practice Medical Center, West China Hospital, Sichuan University, Chengdu, China
| | - Xuelian Liu
- General Practice Medical Center, West China Hospital, Sichuan University, Chengdu, China
| | - Jing Luo
- General Practice Medical Center, West China Hospital, Sichuan University, Chengdu, China
| | - Tao Wu
- Department of Rehabilitation Medicine, West China Hospital, Sichuan University, Chengdu, China
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4
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Pierce M, Ji J, Novak SX, Sieburg MA, Nangia S, Nangia S, Hougland JL. Combined Computational-Biochemical Approach Offers an Accelerated Path to Membrane Protein Solubilization. J Chem Inf Model 2023; 63:7159-7170. [PMID: 37939203 PMCID: PMC10685452 DOI: 10.1021/acs.jcim.3c00917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 10/25/2023] [Accepted: 10/25/2023] [Indexed: 11/10/2023]
Abstract
Membrane proteins are difficult to isolate and purify due to their dependence on the surrounding lipid membrane for structural stability. Detergents are often used to solubilize these proteins, with this approach requiring a careful balance between protein solubilization and denaturation. Determining which detergent is most appropriate for a given protein has largely been done empirically through screening, which requires large amounts of membrane protein and associated resources. Here, we describe an alternative to conventional detergent screening using a computational modeling approach to identify the most likely candidate detergents for solubilizing a protein of interest. We demonstrate our approach using ghrelin O-acyltransferase (GOAT), a member of the membrane-bound O-acyltransferase family of integral membrane enzymes that has not been solubilized or purified in active form. A computationally derived GOAT structural model provides the only structural information required for this approach. Using computational analysis of detergent ability to penetrate phospholipid bilayers and stabilize the GOAT structure, a panel of common detergents were rank-ordered for their proposed ability to solubilize GOAT. The simulations were performed at all-atom resolution for a combined simulation time of 24 μs. Independently, we biologically screened these detergents for their solubilization of fluorescently tagged GOAT constructs. We found computational prediction of protein structural stabilization was the better predictor of detergent solubilization ability, but neither approach was effective for predicting detergents that would support GOAT enzymatic function. The current rapid expansion of membrane protein computational models lacking experimental structural information and our computational detergent screening approach can greatly improve the efficiency of membrane protein detergent solubilization, supporting downstream functional and structural studies.
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Affiliation(s)
- Mariah
R. Pierce
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | - Jingjing Ji
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
| | - Sadie X. Novak
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | - Michelle A. Sieburg
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
| | - Shivangi Nangia
- Department
of Chemistry, University of Hartford, West Hartford, Connecticut 06117, United States
| | - Shikha Nangia
- Department
of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, United States
- BioInspired
Syracuse, Syracuse, New York 13244, United States
| | - James L. Hougland
- Department
of Chemistry, Syracuse University, Syracuse, New York 13244, United States
- BioInspired
Syracuse, Syracuse, New York 13244, United States
- Department
of Biology, Syracuse University, Syracuse, New York 13244, United States
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5
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Kim DY, Park J, Han IO. Hexosamine biosynthetic pathway and O-GlcNAc cycling of glucose metabolism in brain function and disease. Am J Physiol Cell Physiol 2023; 325:C981-C998. [PMID: 37602414 DOI: 10.1152/ajpcell.00191.2023] [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: 05/23/2023] [Revised: 08/03/2023] [Accepted: 08/03/2023] [Indexed: 08/22/2023]
Abstract
Impaired brain glucose metabolism is considered a hallmark of brain dysfunction and neurodegeneration. Disruption of the hexosamine biosynthetic pathway (HBP) and subsequent O-linked N-acetylglucosamine (O-GlcNAc) cycling has been identified as an emerging link between altered glucose metabolism and defects in the brain. Myriads of cytosolic and nuclear proteins in the nervous system are modified at serine or threonine residues with a single N-acetylglucosamine (O-GlcNAc) molecule by O-GlcNAc transferase (OGT), which can be removed by β-N-acetylglucosaminidase (O-GlcNAcase, OGA). Homeostatic regulation of O-GlcNAc cycling is important for the maintenance of normal brain activity. Although significant evidence linking dysregulated HBP metabolism and aberrant O-GlcNAc cycling to induction or progression of neuronal diseases has been obtained, the issue of whether altered O-GlcNAcylation is causal in brain pathogenesis remains uncertain. Elucidation of the specific functions and regulatory mechanisms of individual O-GlcNAcylated neuronal proteins in both normal and diseased states may facilitate the identification of novel therapeutic targets for various neuronal disorders. The information presented in this review highlights the importance of HBP/O-GlcNAcylation in the neuronal system and summarizes the roles and potential mechanisms of O-GlcNAcylated neuronal proteins in maintaining normal brain function and initiation and progression of neurological diseases.
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Affiliation(s)
- Dong Yeol Kim
- Department of Biomedical Science, Program in Biomedical Science and Engineering, College of Medicine, Inha University, Incheon, South Korea
| | - Jiwon Park
- Department of Biomedical Science, Program in Biomedical Science and Engineering, College of Medicine, Inha University, Incheon, South Korea
| | - Inn-Oc Han
- Department of Biomedical Science, Program in Biomedical Science and Engineering, College of Medicine, Inha University, Incheon, South Korea
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6
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Hart G, Huang CW, Rust N, Wu HF. Altered O-GlcNAcylation and mitochondrial dysfunction, a molecular link between brain glucose dysregulation and sporadic Alzheimer’s disease. Neural Regen Res 2023; 18:779-783. [DOI: 10.4103/1673-5374.354515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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7
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Brosch PK, Korsa T, Taban D, Eiring P, Hildebrand S, Neubauer J, Zimmermann H, Sauer M, Shirakashi R, Djuzenova CS, Sisario D, Sukhorukov VL. Glucose and Inositol Transporters, SLC5A1 and SLC5A3, in Glioblastoma Cell Migration. Cancers (Basel) 2022; 14:5794. [PMID: 36497276 PMCID: PMC9738886 DOI: 10.3390/cancers14235794] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 11/04/2022] [Accepted: 11/20/2022] [Indexed: 11/27/2022] Open
Abstract
(1) Background: The recurrence of glioblastoma multiforme (GBM) is mainly due to invasion of the surrounding brain tissue, where organic solutes, including glucose and inositol, are abundant. Invasive cell migration has been linked to the aberrant expression of transmembrane solute-linked carriers (SLC). Here, we explore the role of glucose (SLC5A1) and inositol transporters (SLC5A3) in GBM cell migration. (2) Methods: Using immunofluorescence microscopy, we visualized the subcellular localization of SLC5A1 and SLC5A3 in two highly motile human GBM cell lines. We also employed wound-healing assays to examine the effect of SLC inhibition on GBM cell migration and examined the chemotactic potential of inositol. (3) Results: While GBM cell migration was significantly increased by extracellular inositol and glucose, it was strongly impaired by SLC transporter inhibition. In the GBM cell monolayers, both SLCs were exclusively detected in the migrating cells at the monolayer edge. In single GBM cells, both transporters were primarily localized at the leading edge of the lamellipodium. Interestingly, in GBM cells migrating via blebbing, SLC5A1 and SLC5A3 were predominantly detected in nascent and mature blebs, respectively. (4) Conclusion: We provide several lines of evidence for the involvement of SLC5A1 and SLC5A3 in GBM cell migration, thereby complementing the migration-associated transportome. Our findings suggest that SLC inhibition is a promising approach to GBM treatment.
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Affiliation(s)
- Philippa K. Brosch
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Tessa Korsa
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
- Fraunhofer Institute for Biomedical Engineering (IBMT), 66280 Sulzbach, Germany
| | - Danush Taban
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Patrick Eiring
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Sascha Hildebrand
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Julia Neubauer
- Fraunhofer Institute for Biomedical Engineering (IBMT), 66280 Sulzbach, Germany
| | - Heiko Zimmermann
- Fraunhofer Institute for Biomedical Engineering (IBMT), 66280 Sulzbach, Germany
- Department of Molecular and Cellular Biotechnology, Saarland University, 66123 Saarbrücken, Germany
- Faculty of Marine Science, Universidad Católica del Norte, Coquimbo 1281, Chile
| | - Markus Sauer
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Ryo Shirakashi
- Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505, Japan
| | - Cholpon S. Djuzenova
- Department of Radiation Oncology, University Hospital of Würzburg, 97080 Würzburg, Germany
| | - Dmitri Sisario
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
| | - Vladimir L. Sukhorukov
- Department of Biotechnology & Biophysics, Biocenter, University of Würzburg, 97074 Würzburg, Germany
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8
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Nakhal MM, Aburuz S, Sadek B, Akour A. Repurposing SGLT2 Inhibitors for Neurological Disorders: A Focus on the Autism Spectrum Disorder. Molecules 2022; 27:7174. [PMID: 36364000 PMCID: PMC9653623 DOI: 10.3390/molecules27217174] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 10/13/2022] [Accepted: 10/19/2022] [Indexed: 09/29/2023] Open
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a substantially increasing incidence rate. It is characterized by repetitive behavior, learning difficulties, deficits in social communication, and interactions. Numerous medications, dietary supplements, and behavioral treatments have been recommended for the management of this condition, however, there is no cure yet. Recent studies have examined the therapeutic potential of the sodium-glucose cotransporter 2 (SGLT2) inhibitors in neurodevelopmental diseases, based on their proved anti-inflammatory effects, such as downregulating the expression of several proteins, including the transforming growth factor beta (TGF-β), interleukin-6 (IL-6), C-reactive protein (CRP), nuclear factor κB (NF-κB), tumor necrosis factor alpha (TNF-α), and the monocyte chemoattractant protein (MCP-1). Furthermore, numerous previous studies revealed the potential of the SGLT2 inhibitors to provide antioxidant effects, due to their ability to reduce the generation of free radicals and upregulating the antioxidant systems, such as glutathione (GSH) and superoxide dismutase (SOD), while crossing the blood brain barrier (BBB). These properties have led to significant improvements in the neurologic outcomes of multiple experimental disease models, including cerebral oxidative stress in diabetes mellitus and ischemic stroke, Alzheimer's disease (AD), Parkinson's disease (PD), and epilepsy. Such diseases have mutual biomarkers with ASD, which potentially could be a link to fill the gap of the literature studying the potential of repurposing the SGLT2 inhibitors' use in ameliorating the symptoms of ASD. This review will look at the impact of the SGLT2 inhibitors on neurodevelopmental disorders on the various models, including humans, rats, and mice, with a focus on the SGLT2 inhibitor canagliflozin. Furthermore, this review will discuss how SGLT2 inhibitors regulate the ASD biomarkers, based on the clinical evidence supporting their functions as antioxidant and anti-inflammatory agents capable of crossing the blood-brain barrier (BBB).
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Affiliation(s)
- Mohammed Moutaz Nakhal
- Department of Biochemistry, College of Medicine and Health Sciences, Al-Ain P.O. Box 15551, United Arab Emirates
| | - Salahdein Aburuz
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, Al-Ain P.O. Box 15551, United Arab Emirates
- Zayed Center for Health Sciences, United Arab Emirates University, Al-Ain P.O. Box 17666, United Arab Emirates
- Department of Biopharmaceutics and Clinical Pharmacy, School of Pharmacy, The University of Jordan, Amman 11942, Jordan
| | - Bassem Sadek
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, Al-Ain P.O. Box 15551, United Arab Emirates
- Zayed Center for Health Sciences, United Arab Emirates University, Al-Ain P.O. Box 17666, United Arab Emirates
| | - Amal Akour
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, Al-Ain P.O. Box 15551, United Arab Emirates
- Zayed Center for Health Sciences, United Arab Emirates University, Al-Ain P.O. Box 17666, United Arab Emirates
- Department of Biopharmaceutics and Clinical Pharmacy, School of Pharmacy, The University of Jordan, Amman 11942, Jordan
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9
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Kundu P, Holden S, Paraiso IL, Sudhakar R, McQuesten C, Choi J, Miranda CL, Maier CS, Bobe G, Stevens JF, Raber J. ApoE isoform-dependent effects of xanthohumol on high fat diet-induced cognitive impairments and hippocampal metabolic pathways. Front Pharmacol 2022; 13:954980. [PMID: 36278228 PMCID: PMC9583926 DOI: 10.3389/fphar.2022.954980] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 07/25/2022] [Indexed: 11/25/2022] Open
Abstract
Consumption of a high fat diet (HFD) is linked to metabolic syndrome and cognitive impairments. This is exacerbated in age-related cognitive decline (ACD) and in individuals with a genetic risk for Alzheimer's disease (AD). Apolipoprotein E (apoE) is involved in cholesterol metabolism. In humans, there are three major isoforms, E2, E3, and E4. Compared to E3, E4 increases ACD and AD risk and vulnerability to the deleterious cognitive effects of a HFD. The plant compound Xanthohumol (XN) had beneficial effects on cognition and metabolism in C57BL/6J wild-type (WT) male mice put on a HFD at 9 weeks of age for 13 weeks. As the effects of XN in the context of a HFD in older WT, E3, and E4 female and male mice are not known, in the current study male and female WT, E3, and E4 mice were fed a HFD alone or a HFD containing 0.07% XN for 10 or 19 weeks, starting at 6 months of age, prior to the beginning of behavioral and cognitive testing. XN showed sex- and ApoE isoform-dependent effects on cognitive performance. XN-treated E4 and WT, but not E3, mice had higher glucose transporter protein levels in the hippocampus and cortex than HFD-treated mice. E3 and E4 mice had higher glucose transporter protein levels in the hippocampus and lower glucose transporter protein levels in the cortex than WT mice. In the standard experiment, regardless of XN treatment, E4 mice had nearly double as high ceramide and sphingomyelin levels than E3 mice and male mice had higher level of glycosylated ceramide than female mice. When the differential effects of HFD in E3 and E4 males were assessed, the arginine and proline metabolism pathway was affected. In the extended exposure experiment, in E3 males XN treatment affected the arginine and proline metabolism and the glycine, serine, and threonine metabolism. Myristic acid levels were decreased in XN-treated E3 males but not E3 females. These data support the therapeutic potential for XN to ameliorate HFD-induced cognitive impairments and highlight the importance of considering sex and ApoE isoform in determining who might most benefit from this dietary supplement.
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Affiliation(s)
- Payel Kundu
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Sarah Holden
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Ines L. Paraiso
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR, United States
| | - Reetesh Sudhakar
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Chloe McQuesten
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
| | - Jaewoo Choi
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
| | - Cristobal L. Miranda
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR, United States
| | - Claudia S. Maier
- Department of Chemistry, Oregon State University, Corvallis, OR, United States
| | - Gerd Bobe
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
- Department of Animal and Rangeland Sciences, Oregon State University, Corvallis, OR, United States
| | - Jan F. Stevens
- Linus Pauling Institute, Oregon State University, Corvallis, OR, United States
- Department of Pharmaceutical Sciences, Oregon State University, Corvallis, OR, United States
| | - Jacob Raber
- Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, OR, United States
- Departments of Neurology and Radiation Medicine, Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, Portland, OR, United States
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10
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Engel MG, Smith J, Mao K, Quipildor GF, Cui MH, Gulinello M, Branch CA, Gandy SE, Huffman DM. Evidence for preserved insulin responsiveness in the aging rat brain. GeroScience 2022; 44:2491-2508. [PMID: 35798912 PMCID: PMC9768080 DOI: 10.1007/s11357-022-00618-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 06/27/2022] [Indexed: 01/06/2023] Open
Abstract
Insulin appears to exert salutary effects in the central nervous system (CNS). Thus, brain insulin resistance has been proposed to play a role in brain aging and dementia but is conceptually complex and unlikely to fit classic definitions established in peripheral tissues. Thus, we sought to characterize brain insulin responsiveness in young (4-5 months) and old (24 months) FBN male rats using a diverse set of assays to determine the extent to which insulin effects in the CNS are impaired with age. When performing hyperinsulinemic-euglycemic clamps in rats, intracerebroventricular (ICV) infusion of insulin in old animals improved peripheral insulin sensitivity by nearly two-fold over old controls and comparable to young rats, suggesting preservation of this insulin-triggered response in aging per se (p < 0.05). We next used an imaging-based approach by comparing ICV vehicle versus insulin and performed resting state functional magnetic resonance imaging (rs-fMRI) to evaluate age- and insulin-related changes in network connectivity within the default mode network. In aging, lower connectivity between the mesial temporal (MT) region and other areas, as well as reduced MT signal complexity, was observed in old rats, which correlated with greater cognitive deficits in old. Despite these stark differences, ICV insulin failed to elicit any significant alteration to the BOLD signal in young rats, while a significant deviation of the BOLD signal was observed in older animals, characterized by augmentation in regions of the septal nucleus and hypothalamus, and reduction in thalamus and nucleus accumbens. In contrast, ex vivo stimulation of hippocampus with 10 nM insulin revealed increased Akt activation in young (p < 0.05), but not old rats. Despite similar circulating levels of insulin and IGF-1, cerebrospinal fluid concentrations of these ligands were reduced with age. Thus, these data highlight the complexity of capturing brain insulin action and demonstrate preserved or heightened brain responses to insulin with age, despite dampened canonical signaling, thereby suggesting impaired CNS input of these ligands may be a feature of reduced brain insulin action, providing further rationale for CNS replacement strategies.
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Affiliation(s)
- Matthew G Engel
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
- Institute for Aging Research, Albert Einstein College of Medicine, 1300 Morris Park Ave, Golding Building Room 201, BronxBronx, NY, 10461, USA
| | - Jeremy Smith
- Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, GA, USA
| | - Kai Mao
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
- Institute for Aging Research, Albert Einstein College of Medicine, 1300 Morris Park Ave, Golding Building Room 201, BronxBronx, NY, 10461, USA
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Gabriela Farias Quipildor
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
- Institute for Aging Research, Albert Einstein College of Medicine, 1300 Morris Park Ave, Golding Building Room 201, BronxBronx, NY, 10461, USA
| | - Min-Hui Cui
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Maria Gulinello
- Dominick S. Purpura Department of Neuroscience, Behavioral Core Facility, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Craig A Branch
- Department of Radiology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Samuel E Gandy
- Department of Neurology and the Mount Sinai Center for Cognitive Health, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
- Department of Psychiatry and the Mount Sinai Alzheimer's Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, 10029, USA
| | - Derek M Huffman
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
- Institute for Aging Research, Albert Einstein College of Medicine, 1300 Morris Park Ave, Golding Building Room 201, BronxBronx, NY, 10461, USA.
- Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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11
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Kuebler IRK, Jolton JA, Hermreck C, Hubbard NA, Wakabayashi KT. Contrasting dose-dependent effects of acute intravenous methamphetamine on lateral hypothalamic extracellular glucose dynamics in male and female rats. J Neurophysiol 2022; 128:819-836. [PMID: 36043803 PMCID: PMC9529272 DOI: 10.1152/jn.00257.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/22/2022] [Accepted: 08/24/2022] [Indexed: 11/22/2022] Open
Abstract
Glucose is the brain's primary energetic resource. The brain's use of glucose is dynamic, balancing delivery from the neurovasculature with local metabolism. Although glucose metabolism is known to differ in humans with and without methamphetamine use disorder (MUD), it is unknown how central glucose regulation changes with acute methamphetamine experience. Here, we determined how intravenous methamphetamine regulates extracellular glucose levels in a brain region implicated in MUD-like behavior, the lateral hypothalamus (LH). We measured extracellular LH glucose in awake adult male and female drug-naive Wistar rats using enzyme-linked amperometric glucose biosensors. Changes in LH glucose were monitored during a single session after: 1) natural nondrug stimuli (novel object presentation and a tail-touch), 2) increasing cumulative doses of intravenous methamphetamine (0.025, 0.05, 0.1, and 0.2 mg/kg), and 3) an injection of 60 mg of glucose. We found second-scale fluctuations in LH glucose in response to natural stimuli that differed by both stimulus type and sex. Although rapid, second-scale changes in LH glucose during methamphetamine injections were variable, slow, minute-scale changes following most injections were robust and resulted in a reduction in LH glucose levels. Dose and sex differences at this timescale indicated that female rats may be more sensitive to the impact of methamphetamine on central glucose regulation. These findings suggest that the effects of MUD on healthy brain function may be linked to how methamphetamine alters extracellular glucose regulation in the LH and point to possible mechanisms by which methamphetamine influences central glucose metabolism more broadly.NEW & NOTEWORTHY Enzyme-linked glucose biosensors were used to monitor lateral hypothalamic (LH) extracellular fluctuations during nondrug stimuli and intravenous methamphetamine injections in drug-naive awake male and female rats. Second-scale glucose changes occurred after nondrug stimuli, differing by modality and sex. Robust minute-scale decreases followed most methamphetamine injections. Sex differences at the minute-scale indicate female central glucose regulation is more sensitive to methamphetamine effects. We discuss likely mechanisms underlying these fluctuations, and their implications in methamphetamine use disorder.
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Affiliation(s)
- Isabel R K Kuebler
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Joshua A Jolton
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Chase Hermreck
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Nicholas A Hubbard
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Ken T Wakabayashi
- Neurocircuitry of Motivated Behavior Laboratory, Department of Psychology, University of Nebraska-Lincoln, Lincoln, Nebraska
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12
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Effect of cx-DHED on Abnormal Glucose Transporter Expression Induced by AD Pathologies in the 5xFAD Mouse Model. Int J Mol Sci 2022; 23:ijms231810602. [PMID: 36142509 PMCID: PMC9505457 DOI: 10.3390/ijms231810602] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 09/06/2022] [Accepted: 09/08/2022] [Indexed: 11/17/2022] Open
Abstract
Alzheimer’s disease (AD) is a form of dementia associated with abnormal glucose metabolism resulting from amyloid-beta (Aβ) plaques and intracellular neurofibrillary tau protein tangles. In a previous study, we confirmed that carboxy-dehydroevodiamine∙HCl (cx-DHED), a derivative of DHED, was effective at improving cognitive impairment and reducing phosphorylated tau levels and synaptic loss in an AD mouse model. However, the specific mechanism of action of cx-DHED is unclear. In this study, we investigated how the cx-DHED attenuates AD pathologies in the 5xFAD mouse model, focusing particularly on abnormal glucose metabolism. We analyzed behavioral changes and AD pathologies in mice after intraperitoneal injection of cx-DHED for 2 months. As expected, cx-DHED reversed memory impairment and reduced Aβ plaques and astrocyte overexpression in the brains of 5xFAD mice. Interestingly, cx-DHED reversed the abnormal expression of glucose transporters in the brains of 5xFAD mice. In addition, otherwise low O-GlcNac levels increased, and the overactivity of phosphorylated GSK-3β decreased in the brains of cx-DHED-treated 5xFAD mice. Finally, the reduction in synaptic proteins was found to also improve by treatment with cx-DHED. Therefore, we specifically demonstrated the protective effects of cx-DHED against AD pathologies and suggest that cx-DHED may be a potential therapeutic drug for AD.
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13
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Luo M, Zeng Q, Jiang K, Zhao Y, Long Z, Du Y, Wang K, He G. Estrogen deficiency exacerbates learning and memory deficits associated with glucose metabolism disorder in APP/PS1 double transgenic female mice. Genes Dis 2022; 9:1315-1331. [PMID: 35873026 PMCID: PMC9293702 DOI: 10.1016/j.gendis.2021.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 01/15/2021] [Accepted: 01/27/2021] [Indexed: 11/27/2022] Open
Abstract
Alterations in glucose metabolism occur in the brain in the early stage of Alzheimer's disease (AD), and menopausal women have more severe metabolic dysfunction and are more prone to dementia than men. Although estrogen deficiency-induced changes in glucose metabolism have been previously studied in animal models, their molecular mechanisms in AD remain elusive. To investigate this issue, double transgenic (APP/PS1) female mice were subjected to bilateral ovariectomy at 3 months of age and were sacrificed 1 week, 1 month and 3 months after surgery to simulate early, middle and late postmenopause, respectively. Our analysis demonstrated that estrogen deficiency exacerbates learning and memory deficits in this mouse model of postmenopause. Estrogen deficiency impairs the function of mitochondria in glucose metabolism. It is possible that the occurrence of AD is associated with the aberrant mitochondrial ERβ-mediated IGF-1/IGF-1R/GSK-3β signaling pathway. In this study, we established a potential mechanism for the increased risk of AD in postmenopausal women and proposed a therapeutic target for AD due to postmenopause.
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Affiliation(s)
- Min Luo
- Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing 400016, PR China.,Department of Pathology, Suining Municipal Hospital of TCM, Suining, Sichuan 629000, PR China
| | - Qinghua Zeng
- Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing 400016, PR China.,Department of Anatomy, Chongqing Medical University, Chongqing 400016, PR China
| | - Kai Jiang
- Department of Gastroenterology, Suining Central Hospital, Suining, Sichuan 629000, PR China
| | - Yueyang Zhao
- Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing 400016, PR China
| | - Zhimin Long
- Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing 400016, PR China.,Department of Anatomy, Chongqing Medical University, Chongqing 400016, PR China
| | - Yexiang Du
- Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing 400016, PR China
| | - Kejian Wang
- Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing 400016, PR China.,Department of Anatomy, Chongqing Medical University, Chongqing 400016, PR China
| | - Guiqiong He
- Chongqing Key Laboratory of Neurobiology, Chongqing Medical University, Chongqing 400016, PR China.,Department of Anatomy, Chongqing Medical University, Chongqing 400016, PR China
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14
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Kaggie JD, Khan AS, Matys T, Schulte RF, Locke MJ, Grimmer A, Frary A, Menih IH, Latimer E, Graves MJ, McLean MA, Gallagher FA. Deuterium metabolic imaging and hyperpolarized 13C-MRI of the normal human brain at clinical field strength reveals differential cerebral metabolism. Neuroimage 2022; 257:119284. [PMID: 35533826 DOI: 10.1016/j.neuroimage.2022.119284] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 05/02/2022] [Accepted: 05/04/2022] [Indexed: 12/01/2022] Open
Abstract
Deuterium metabolic imaging (DMI) and hyperpolarized 13C-pyruvate MRI (13C-HPMRI) are two emerging methods for non-invasive and non-ionizing imaging of tissue metabolism. Imaging cerebral metabolism has potential applications in cancer, neurodegeneration, multiple sclerosis, traumatic brain injury, stroke, and inborn errors of metabolism. Here we directly compare these two non-invasive methods at 3 T for the first time in humans and show how they simultaneously probe both oxidative and non-oxidative metabolism. DMI was undertaken 1-2 h after oral administration of [6,6'-2H2]glucose, and 13C-MRI was performed immediately following intravenous injection of hyperpolarized [1-13C]pyruvate in ten and nine normal volunteers within each arm respectively. DMI was used to generate maps of deuterium-labelled water, glucose, lactate, and glutamate/glutamine (Glx) and the spectral separation demonstrated that DMI is feasible at 3 T. 13C-HPMRI generated maps of hyperpolarized carbon-13 labelled pyruvate, lactate, and bicarbonate. The ratio of 13C-lactate/13C-bicarbonate (mean 3.7 ± 1.2) acquired with 13C-HPMRI was higher than the equivalent 2H-lactate/2H-Glx ratio (mean 0.18 ± 0.09) acquired using DMI. These differences can be explained by the route of administering each probe, the timing of imaging after ingestion or injection, as well as the biological differences in cerebral uptake and cellular physiology between the two molecules. The results demonstrate these two metabolic imaging methods provide different yet complementary readouts of oxidative and reductive metabolism within a clinically feasible timescale. Furthermore, as DMI was undertaken at a clinical field strength within a ten-minute scan time, it demonstrates its potential as a routine clinical tool in the future.
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Affiliation(s)
- Joshua D Kaggie
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK.
| | - Alixander S Khan
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK
| | - Tomasz Matys
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK
| | | | - Matthew J Locke
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK
| | - Ashley Grimmer
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK
| | - Amy Frary
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK
| | - Ines Horvat Menih
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK
| | - Elizabeth Latimer
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK
| | - Martin J Graves
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK
| | - Mary A McLean
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK; Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge UK
| | - Ferdia A Gallagher
- Department of Radiology, University of Cambridge, Box 218, Cambridge Biomedical Campus, Cambridge CB2 0QQ, UK; Cambridge University Hospitals, Addenbrooke's Hospital, Cambridge, UK; Cancer Research UK Cambridge Centre, University of Cambridge, Cambridge, UK
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15
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Abstract
Alzheimer’s disease (AD) is the most common major neurocognitive disorder of ageing. Although largely ignored until about a decade ago, accumulating evidence suggests that deteriorating brain energy metabolism plays a key role in the development and/or progression of AD-associated cognitive decline. Brain glucose hypometabolism is a well-established biomarker in AD but was mostly assumed to be a consequence of neuronal dysfunction and death. However, its presence in cognitively asymptomatic populations at higher risk of AD strongly suggests that it is actually a pre-symptomatic component in the development of AD. The question then arises as to whether progressive AD-related cognitive decline could be prevented or slowed down by correcting or bypassing this progressive ‘brain energy gap’. In this review, we provide an overview of research on brain glucose and ketone metabolism in AD and its prodromal condition – mild cognitive impairment (MCI) – to provide a clearer basis for proposing keto-therapeutics as a strategy for brain energy rescue in AD. We also discuss studies using ketogenic interventions and their impact on plasma ketone levels, brain energetics and cognitive performance in MCI and AD. Given that exercise has several overlapping metabolic effects with ketones, we propose that in combination these two approaches might be synergistic for brain health during ageing. As cause-and-effect relationships between the different hallmarks of AD are emerging, further research efforts should focus on optimising the efficacy, acceptability and accessibility of keto-therapeutics in AD and populations at risk of AD.
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16
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Reiterer M, Eakin A, Johnson RS, Branco CM. Hyperoxia Reprogrammes Microvascular Endothelial Cell Response to Hypoxia in an Organ-Specific Manner. Cells 2022; 11:cells11162469. [PMID: 36010546 PMCID: PMC9406746 DOI: 10.3390/cells11162469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/27/2022] [Accepted: 08/02/2022] [Indexed: 11/16/2022] Open
Abstract
Organ function relies on microvascular networks to maintain homeostatic equilibrium, which varies widely in different organs and during different physiological challenges. The endothelium role in this critical process can only be evaluated in physiologically relevant contexts. Comparing the responses to oxygen flux in primary murine microvascular EC (MVEC) obtained from brain and lung tissue reveals that supra-physiological oxygen tensions can compromise MVEC viability. Brain MVEC lose mitochondrial activity and undergo significant alterations in electron transport chain (ETC) composition when cultured under standard, non-physiological atmospheric oxygen levels. While glycolytic capacity of both lung and brain MVEC are unchanged by environmental oxygen, the ability to trigger a metabolic shift when oxygen levels drop is greatly compromised following exposure to hyperoxia. This is particularly striking in MVEC from the brain. This work demonstrates that the unique metabolism and function of organ-specific MVEC (1) can be reprogrammed by external oxygen, (2) that this reprogramming can compromise MVEC survival and, importantly, (3) that ex vivo modelling of endothelial function is significantly affected by culture conditions. It further demonstrates that physiological, metabolic and functional studies performed in non-physiological environments do not represent cell function in situ, and this has serious implications in the interpretation of cell-based pre-clinical models.
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Affiliation(s)
- Moritz Reiterer
- Patrick G Johnston Centre for Cancer Research, Queen’s University, Belfast BT9 7AE, UK
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Amanda Eakin
- Patrick G Johnston Centre for Cancer Research, Queen’s University, Belfast BT9 7AE, UK
| | - Randall S. Johnson
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3EG, UK
| | - Cristina M. Branco
- Patrick G Johnston Centre for Cancer Research, Queen’s University, Belfast BT9 7AE, UK
- Correspondence:
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17
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The Therapeutic Role of Ketogenic Diet in Neurological Disorders. Nutrients 2022; 14:nu14091952. [PMID: 35565918 PMCID: PMC9102882 DOI: 10.3390/nu14091952] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 04/30/2022] [Accepted: 05/04/2022] [Indexed: 02/01/2023] Open
Abstract
The ketogenic diet (KD) is a high-fat, low-carbohydrate and adequate-protein diet that has gained popularity in recent years in the context of neurological diseases (NDs). The complexity of the pathogenesis of these diseases means that effective forms of treatment are still lacking. Conventional therapy is often associated with increasing tolerance and/or drug resistance. Consequently, more effective therapeutic strategies are being sought to increase the effectiveness of available forms of therapy and improve the quality of life of patients. For the moment, it seems that KD can provide therapeutic benefits in patients with neurological problems by effectively controlling the balance between pro- and antioxidant processes and pro-excitatory and inhibitory neurotransmitters, and modulating inflammation or changing the composition of the gut microbiome. In this review we evaluated the potential therapeutic efficacy of KD in epilepsy, depression, migraine, Alzheimer’s disease and Parkinson’s disease. In our opinion, KD should be considered as an adjuvant therapeutic option for some neurological diseases.
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18
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Brain Endothelial Cells Utilize Glycolysis for the Maintenance of the Transcellular Permeability. Mol Neurobiol 2022; 59:4315-4333. [PMID: 35508867 DOI: 10.1007/s12035-022-02778-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 02/19/2022] [Indexed: 10/18/2022]
Abstract
Among the components of the blood-brain barrier (BBB), endothelial cells (ECs) play an important role in supplying limited materials, especially glucose, to the brain. However, the mechanism by which glucose is metabolized in brain ECs is still elusive. To address this topic, we assessed the metabolic signature of glucose utilization using live-cell metabolic assays and liquid chromatography-tandem mass spectrometry metabolomic analysis. We found that brain ECs are highly dependent on aerobic glycolysis, generating lactate as its final product with minimal consumption of glucose. Glucose treatment decreased the oxygen consumption rate in a dose-dependent manner, indicating the Crabtree effect. Moreover, when glycolysis was inhibited, brain ECs showed impaired permeability to molecules utilizing transcellular pathway. In addition, we found that the blockade of glycolysis in mouse brain with 2-deoxyglucose administration resulted in decreased transcellular permeability of the BBB. In conclusion, utilizing glycolysis in brain ECs has critical roles in the maintenance and permeability of the BBB. Overall, we could conclude that brain ECs are highly glycolytic, and their energy can be used to maintain the transcellular permeability of the BBB.
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19
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Dysmetabolism and Neurodegeneration: Trick or Treat? Nutrients 2022; 14:nu14071425. [PMID: 35406040 PMCID: PMC9003269 DOI: 10.3390/nu14071425] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 03/24/2022] [Accepted: 03/25/2022] [Indexed: 02/06/2023] Open
Abstract
Accumulating evidence suggests the existence of a strong link between metabolic syndrome and neurodegeneration. Indeed, epidemiologic studies have described solid associations between metabolic syndrome and neurodegeneration, whereas animal models contributed for the clarification of the mechanistic underlying the complex relationships between these conditions, having the development of an insulin resistance state a pivotal role in this relationship. Herein, we review in a concise manner the association between metabolic syndrome and neurodegeneration. We start by providing concepts regarding the role of insulin and insulin signaling pathways as well as the pathophysiological mechanisms that are in the genesis of metabolic diseases. Then, we focus on the role of insulin in the brain, with special attention to its function in the regulation of brain glucose metabolism, feeding, and cognition. Moreover, we extensively report on the association between neurodegeneration and metabolic diseases, with a particular emphasis on the evidence observed in animal models of dysmetabolism induced by hypercaloric diets. We also debate on strategies to prevent and/or delay neurodegeneration through the normalization of whole-body glucose homeostasis, particularly via the modulation of the carotid bodies, organs known to be key in connecting the periphery with the brain.
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20
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Watanabe J, Watanabe M, Yamaoka K, Adachi M, Suzuki A, Tango T, Professor V. Effects of 'SPRAT' programme for dietary and lifestyle education to improve psychosomatic symptoms and dietary habits among adolescents: a cluster randomised controlled trial. BMC Public Health 2022; 22:461. [PMID: 35255866 PMCID: PMC8903559 DOI: 10.1186/s12889-022-12832-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 02/22/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dietary and lifestyle modifications to reduce subjective psychosomatic symptoms (SPS) have become an important topic worldwide. We developed a school-based dietary and lifestyle education programme that involved parents/guardians in reducing SPS in adolescents (SPRAT). The programme encouraged parents/guardians to participate in adolescents' healthy dietary and lifestyle modifications to reduce SPS, increase enjoyment of school life, and foster appropriate dietary intake. This study evaluated the effectiveness of SPRAT in reducing SPS and in altering dietary behaviour among adolescents. METHODS A 6-month cluster randomised controlled trial using SPRAT and the usual school programme (control) was performed. Participants were middle school students in Japan who provided informed consent. Outcomes were SPS scores assessed at baseline and 2, 4, and 6 months after baseline and the proportions of dietary and lifestyle factors achieved such as enjoyment of school life and dietary intakes assessed by FFQW82. Change from baseline (CFB) at 6 months was the primary endpoint. A linear mixed-effects model was applied. As for dietary intake, the treatment effect was estimated as an interaction term between baseline and treatment "baseline*treatment". RESULTS The intention-to treat analysis included 951 (94.7%) and 1035 (89.8%) individuals in the SPRAT and control groups, respectively. The CFB in the 6-month SPS score adjusted for baseline was lower in the SPRAT group (-0.29) than in the control group (0.62), but the difference was not statistically significant -0.91 (p = 0.093). CONCLUSIONS Although the primary endpoint tended to denote improvement in the SPRAT group compared to the control group, the improvement was not significant. Favourable effects were observed in some secondary outcomes and statistically significant treatment*baseline interactions were observed for several dietary intakes. These results imply that CFBs of dietary intake were increased or decreased in a favourable direction depending on the baseline intake, especially in the SPRAT group. TRIAL REGISTRATION UMIN000026715. (27/03/2017).
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Affiliation(s)
- Junko Watanabe
- The Department of Nutrition Management, Minami Kyushu University, Miyazaki, Japan
| | | | - Kazue Yamaoka
- Teikyo University Graduate School of Public Health, 2-11-1, Kaga Itabashi-ku, 1738605, Tokyo, Japan.
| | - Misa Adachi
- Nutrition Support Network LLC, Kanagawa, Japan
| | - Asuka Suzuki
- Teikyo University Graduate School of Public Health, 2-11-1, Kaga Itabashi-ku, 1738605, Tokyo, Japan
| | | | - Visiting Professor
- Teikyo University Graduate School of Public Health, 2-11-1, Kaga Itabashi-ku, 1738605, Tokyo, Japan
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21
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Cacciatore M, Grasso EA, Tripodi R, Chiarelli F. Impact of glucose metabolism on the developing brain. Front Endocrinol (Lausanne) 2022; 13:1047545. [PMID: 36619556 PMCID: PMC9816389 DOI: 10.3389/fendo.2022.1047545] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Accepted: 12/13/2022] [Indexed: 12/24/2022] Open
Abstract
Glucose is the most important substrate for proper brain functioning and development, with an increased glucose consumption in relation to the need of creating new brain structures and connections. Therefore, alterations in glucose homeostasis will inevitably be associated with changes in the development of the Nervous System. Several studies demonstrated how the alteration of glucose homeostasis - both hyper and hypoglycemia- may interfere with the development of brain structures and cognitivity, including deficits in intelligence quotient, anomalies in learning and memory, as well as differences in the executive functions. Importantly, differences in brain structure and functionality were found after a single episode of diabetic ketoacidosis suggesting the importance of glycemic control and stressing the need of screening programs for type 1 diabetes to protect children from this dramatic condition. The exciting progresses of the neuroimaging techniques such as diffusion tensor imaging, has helped to improve the understanding of the effects, outcomes and mechanisms underlying brain changes following dysglycemia, and will lead to more insights on the physio-pathological mechanisms and related neurological consequences about hyper and hypoglycemia.
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22
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Nguyen YTK, Ha HTT, Nguyen TH, Nguyen LN. The role of SLC transporters for brain health and disease. Cell Mol Life Sci 2021; 79:20. [PMID: 34971415 PMCID: PMC11071821 DOI: 10.1007/s00018-021-04074-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 09/05/2021] [Accepted: 10/21/2021] [Indexed: 12/19/2022]
Abstract
The brain exchanges nutrients and small molecules with blood via the blood-brain barrier (BBB). Approximately 20% energy intake for the body is consumed by the brain. Glucose is known for its critical roles for energy production and provides substrates for biogenesis in neurons. The brain takes up glucose via glucose transporters GLUT1 and 3, which are expressed in several neural cell types. The brain is also equipped with various transport systems for acquiring amino acids, lactate, ketone bodies, lipids, and cofactors for neuronal functions. Unraveling the mechanisms by which the brain takes up and metabolizes these nutrients will be key in understanding the nutritional requirements in the brain. This could also offer opportunities for therapeutic interventions in several neurological disorders. For instance, emerging evidence suggests a critical role of lactate as an alternative energy source for neurons. Neuronal cells express monocarboxylic transporters to acquire lactate. As such, treatment of GLUT1-deficient patients with ketogenic diets to provide the brain with alternative sources of energy has been shown to improve the health of the patients. Many transporters are present in the brain, but only a small number has been characterized. In this review, we will discuss about the roles of solute carrier (SLC) transporters at the blood brain barrier (BBB) and neural cells, in transport of nutrients and metabolites in the brain.
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Affiliation(s)
- Yen T K Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117596, Singapore
| | - Hoa T T Ha
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117596, Singapore
| | - Tra H Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117596, Singapore
| | - Long N Nguyen
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117596, Singapore.
- SLING/Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, 117456, Singapore.
- Immunology Translational and Cardiovascular Disease Research Programme, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117545, Singapore.
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23
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An identification of MARK inhibitors using high throughput MALDI-TOF mass spectrometry. Biomed Pharmacother 2021; 146:112549. [PMID: 34923338 DOI: 10.1016/j.biopha.2021.112549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 12/08/2021] [Accepted: 12/13/2021] [Indexed: 01/06/2023] Open
Abstract
MAP/microtubule affinity-regulating kinases (MARKs) were recently identified as potential drug targets for Alzheimer's disease (AD) due to their role in pathological hyperphosphorylation of tau protein. Hyperphosphorylated tau has decreased affinity for microtubule binding, impairing their stability and associated functions. Destabilization of microtubules in neuronal cells leads to neurodegeneration, and microtubule-unbound tau forms neurofibrillary tangles, one of the primary hallmarks of AD. Many phosphorylation sites of tau protein have been identified, but phosphorylation at Ser262, which occurs in early stages of AD, plays a vital role in the pathological hyperphosphorylation of tau. It has been found that Ser262 is phosphorylated by MARK4, which is currently an intensively studied target for treating Alzheimer's disease and other neurodegenerative diseases. Our present study aimed to develop a high throughput compatible assay to directly detect MARK enzymatic activity using echoacoustic transfer and MALDI-TOF mass spectrometer. We optimized the assay for all four isoforms of MARK and validated its use for identifying potential inhibitors by the screening of 1280 compounds from the LOPAC®1280 International (Library Of Pharmacologically Active Compounds). Six MARK4 inhibitors with IC50 < 1 µM were identified. To demonstrate their therapeutic potential, active compounds were further tested for MARK4 selectivity and ability to cross the blood-brain barrier. Lastly, the molecular docking with the most active inhibitors to predict their interaction with MARK4 was performed.
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Udrea AM, Gradisteanu Pircalabioru G, Boboc AA, Mares C, Dinache A, Mernea M, Avram S. Advanced Bioinformatics Tools in the Pharmacokinetic Profiles of Natural and Synthetic Compounds with Anti-Diabetic Activity. Biomolecules 2021; 11:1692. [PMID: 34827690 PMCID: PMC8615418 DOI: 10.3390/biom11111692] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/06/2021] [Accepted: 11/08/2021] [Indexed: 12/12/2022] Open
Abstract
Diabetes represents a major health problem, involving a severe imbalance of blood sugar levels, which can disturb the nerves, eyes, kidneys, and other organs. Diabes management involves several synthetic drugs focused on improving insulin sensitivity, increasing insulin production, and decreasing blood glucose levels, but with unclear molecular mechanisms and severe side effects. Natural chemicals extracted from several plants such as Gymnema sylvestre, Momordica charantia or Ophiopogon planiscapus Niger have aroused great interest for their anti-diabetes activity, but also their hypolipidemic and anti-obesity activity. Here, we focused on the anti-diabetic activity of a few natural and synthetic compounds, in correlation with their pharmacokinetic/pharmacodynamic profiles, especially with their blood-brain barrier (BBB) permeability. We reviewed studies that used bioinformatics methods such as predicted BBB, molecular docking, molecular dynamics and quantitative structure-activity relationship (QSAR) to elucidate the proper action mechanisms of antidiabetic compounds. Currently, it is evident that BBB damage plays a significant role in diabetes disorders, but the molecular mechanisms are not clear. Here, we presented the efficacy of natural (gymnemic acids, quercetin, resveratrol) and synthetic (TAK-242, propofol, or APX3330) compounds in reducing diabetes symptoms and improving BBB dysfunctions. Bioinformatics tools can be helpful in the quest for chemical compounds with effective anti-diabetic activity that can enhance the druggability of molecular targets and provide a deeper understanding of diabetes mechanisms.
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Affiliation(s)
- Ana Maria Udrea
- Laser Department, National Institute for Laser, Plasma and Radiation Physics, 077125 Maurele, Romania; (A.M.U.); (A.D.)
- Earth, Environmental and Life Sciences Section, Research Institute of the University of Bucharest, University of Bucharest, 1 B. P. Hașdeu St., 50567 Bucharest, Romania;
| | - Gratiela Gradisteanu Pircalabioru
- Earth, Environmental and Life Sciences Section, Research Institute of the University of Bucharest, University of Bucharest, 1 B. P. Hașdeu St., 50567 Bucharest, Romania;
| | - Anca Andreea Boboc
- “Maria Sklodowska Curie” Emergency Children’s Hospital, 20, Constantin Brancoveanu Bd., 077120 Bucharest, Romania;
- Department of Pediatrics 8, “Carol Davila” University of Medicine and Pharmacy, Eroii Sanitari Bd., 020021 Bucharest, Romania
| | - Catalina Mares
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independentei, 050095 Bucharest, Romania; (C.M.); (S.A.)
| | - Andra Dinache
- Laser Department, National Institute for Laser, Plasma and Radiation Physics, 077125 Maurele, Romania; (A.M.U.); (A.D.)
| | - Maria Mernea
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independentei, 050095 Bucharest, Romania; (C.M.); (S.A.)
| | - Speranta Avram
- Department of Anatomy, Animal Physiology and Biophysics, Faculty of Biology, University of Bucharest, 91–95 Splaiul Independentei, 050095 Bucharest, Romania; (C.M.); (S.A.)
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Cisternas P, Gherardelli C, Salazar P, Inestrosa NC. Disruption of Glucose Metabolism in Aged Octodon degus: A Sporadic Model of Alzheimer's Disease. Front Integr Neurosci 2021; 15:733007. [PMID: 34707484 PMCID: PMC8542902 DOI: 10.3389/fnint.2021.733007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/07/2021] [Indexed: 01/04/2023] Open
Abstract
Alzheimer's disease is a progressive neurodegenerative disorder and the most common cause of dementia. Although transgenic Alzheimer's disease (AD) animal models have greatly contributed to our understanding of the disease, therapies tested in these animals have resulted in a high rate of failure in preclinical trials for AD. A promising model is Octodon degus (degu), a Chilean rodent that spontaneously develops AD-like neuropathology. Previous studies have reported that, during aging, degus exhibit a progressive decline in cognitive function, reduced neuroinflammation, and concomitant increases in the number and size of amyloid β (Aβ) plaques in several brain regions. Importantly, in humans and several AD models, a correlation has been shown between brain dysfunction and neuronal glucose utilization impairment, a critical aspect considering the high-energy demand of the brain. However, whether degus develop alterations in glucose metabolism remains unknown. In the present work, we measured several markers of glucose metabolism, namely, glucose uptake, ATP production, and glycolysis and pentose phosphate pathway (PPP) flux, in hippocampal slices from degus of different ages. We found a significant decrease in hippocampal glucose metabolism in aged degus, caused mainly by a drop in glucose uptake, which in turn, reduced ATP synthesis. Moreover, we observed a negative correlation between age and PPP flux. Together, our data further support the use of degus as a model for studying the neuropathology involved in sporadic AD-like pathology and as a potentially valuable tool in the search for effective treatments against the disease.
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Affiliation(s)
- Pedro Cisternas
- Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
| | - Camila Gherardelli
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Centro de Envejecimiento y Regeneración (CARE-UC), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Paulina Salazar
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Centro de Envejecimiento y Regeneración (CARE-UC), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Nibaldo C Inestrosa
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Centro de Envejecimiento y Regeneración (CARE-UC), Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
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26
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Wardzinski EK, Hyzy C, Duysen KU, Melchert UH, Jauch-Chara K, Oltmanns KM. Hypocaloric Dieting Unsettles the Neuroenergetic Homeostasis in Humans. Nutrients 2021; 13:nu13103433. [PMID: 34684431 PMCID: PMC8541113 DOI: 10.3390/nu13103433] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Revised: 09/23/2021] [Accepted: 09/25/2021] [Indexed: 12/15/2022] Open
Abstract
Background: The effects of low-calorie dieting in obesity are disappointing in the long run. The brain’s energy homeostasis plays a key role in the regulation of body weight. We hypothesized that the cerebral energy status underlies an adaptation process upon body weight loss due to hypocaloric dieting in humans. Objective: We instructed 26 healthy obese participants to reduce body weight via replacement of meals by a commercial diet product for two weeks. The cerebral energy status was assessed by 31 phosphorus magnetic resonance spectroscopy (31 PMRS) before and after low-caloric dieting as well as at follow-up. A standardized test buffet was quantified after body weight loss and at follow-up. Blood glucose metabolism and neurohormonal stress axis activity were monitored. Results: Weight loss induced a decline in blood concentrations of insulin (p = 0.002), C-peptide (p = 0.005), ACTH (p = 0.006), and norepinephrine (p = 0.012). ATP/Pi (p = 0.003) and PCr/Pi ratios (p = 0.012) were increased and NADH levels reduced (p = 0.041) after hypocaloric dieting. At follow-up, weight loss persisted (p < 0.001), while insulin, C-peptide, and ACTH increased (p < 0.005 for all) corresponding to baseline levels again. Despite repealed hormonal alterations, ratios of PCr/Pi remained higher (p = 0.039) and NADH levels lower (p = 0.007) 6 weeks after ending the diet. ATP/Pi ratios returned to baseline levels again (p = 0.168). Conclusion: Low-calorie dieting reduces neurohormonal stress axis activity and increases the neuroenergetic status in obesity. This effect was of a transient nature in terms of stress hormonal measures. In contrast, PCr/Pi ratios remained increased after dieting and at follow-up while NADH levels were still reduced, which indicates a persistently unsettled neuroenergetic homeostasis upon diet-induced rapid body weight loss.
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Scavuzzo CJ, Newman LA, Gold PE, Korol DL. Extracellular levels of glucose in the hippocampus and striatum during maze training for food or water reward in male rats. Behav Brain Res 2021; 411:113385. [PMID: 34048874 PMCID: PMC8238909 DOI: 10.1016/j.bbr.2021.113385] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 05/15/2021] [Accepted: 05/22/2021] [Indexed: 12/19/2022]
Abstract
Glucose potently enhances cognitive functions whether given systemically or directly to the brain. The present experiments examined changes in brain extracellular glucose levels while rats were trained to solve hippocampus-sensitive place or striatum-sensitive response learning tasks for food or water reward. Because there were no task-related differences in glucose responses, the glucose results were pooled across tasks to form combined trained groups. During the first 1-3 min of training for food reward, glucose levels in extracellular fluid (ECF) declined significantly in the hippocampus and striatum; the declines were not seen in untrained, rewarded rats. When trained for water reward, similar decreases were observed in both brain areas, but these findings were less consistent than those seen with food rewards. After the initial declines in ECF glucose levels, glucose increased in most groups, approaching asymptotic levels ∼15-30 min into training. Compared to untrained food controls, training with food reward resulted in significant glucose increases in the hippocampus but not striatum; striatal glucose levels exhibited large increases to food intake in both trained and untrained groups. In rats trained to find water, glucose levels increased significantly above the values seen in untrained rats in both hippocampus and striatum. The decreases in glucose early in training might reflect an increase in brain glucose consumption, perhaps triggering increased brain uptake of glucose from blood, as evident in the increases in glucose later in training. The increased brain uptake of glucose may provide additional neuronal metabolic substrate for metabolism or provide astrocytic substrate for production of glycogen and lactate.
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Affiliation(s)
- C J Scavuzzo
- Department of Psychology, University of Alberta, Edmonton, Alberta, T6G 2E9, Canada.
| | - L A Newman
- Department of Psychological Science, Vassar College, 124 Raymond Avenue, Box 713, Poughkeepsie, NY, 12604, United States
| | - P E Gold
- Department of Biology, Syracuse University, Syracuse, NY, 13244, United States
| | - D L Korol
- Department of Biology, Syracuse University, Syracuse, NY, 13244, United States.
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Abstract
The ageing population is becoming a significant socio-economic issue. To address the expanding health gap, it is important to deepen our understanding of the mechanisms underlying ageing in various organisms at the single-cell level. The discovery of the antifungal, immunosuppressive, and anticancer drug rapamycin, which possesses the ability to extend the lifespan of several species, has prompted extensive research in the areas of cell metabolic regulation, development, and senescence. At the centre of this research is the mTOR pathway, with key roles in cell growth, proteosynthesis, ribosomal biogenesis, transcriptional regulation, glucose and lipid metabolism, and autophagy. Recently, it has become obvious that mTOR dysregulation is involved in several age-related diseases, such as cancer, neurodegenerative diseases, and type 2 diabetes mellitus. Additionally, mTOR hyperactivation affects the process of ageing per se. In this review, we provide an overview of recent insights into the mTOR signalling pathway, including its regulation and its influence on various hallmarks of ageing at the cellular level.
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Affiliation(s)
- Zofia Chrienova
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czechia
| | - Eugenie Nepovimova
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czechia
| | - Kamil Kuca
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czechia
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29
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Tsai KF, Chen YL, Chiou TTY, Chu TH, Li LC, Ng HY, Lee WC, Lee CT. Emergence of SGLT2 Inhibitors as Powerful Antioxidants in Human Diseases. Antioxidants (Basel) 2021; 10:1166. [PMID: 34439414 PMCID: PMC8388972 DOI: 10.3390/antiox10081166] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 07/10/2021] [Accepted: 07/19/2021] [Indexed: 12/14/2022] Open
Abstract
Sodium-glucose cotransporter 2 (SGLT2) inhibitors are a new class of oral glucose-lowering agents. Apart from their glucose-lowering effects, large clinical trials assessing certain SGLT2 inhibitors have revealed cardiac and renal protective effects in non-diabetic patients. These excellent outcomes motivated scientists and clinical professionals to revisit their underlying mechanisms. In addition to the heart and kidney, redox homeostasis is crucial in several human diseases, including liver diseases, neural disorders, and cancers, with accumulating preclinical studies demonstrating the therapeutic benefits of SGLT2 inhibitors. In the present review, we aimed to update recent advances in the antioxidant roles of SGLT2 inhibitors in common but debilitating human diseases. We anticipate that this review will guide new research directions and novel therapeutic strategies for diabetes, cardiovascular diseases, nephropathies, liver diseases, neural disorders, and cancers in the era of SGLT2 inhibitors.
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Affiliation(s)
- Kai-Fan Tsai
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (K.-F.T.); (T.T.-Y.C.); (L.-C.L.); (H.-Y.N.)
| | - Yung-Lung Chen
- Section of Cardiology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan;
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan
| | - Terry Ting-Yu Chiou
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (K.-F.T.); (T.T.-Y.C.); (L.-C.L.); (H.-Y.N.)
- School of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan
| | - Tian-Huei Chu
- Department of Medical Research, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan;
- Biobank and Tissue Bank, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan
| | - Lung-Chih Li
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (K.-F.T.); (T.T.-Y.C.); (L.-C.L.); (H.-Y.N.)
- Institute for Translational Research in Biomedicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung 83301, Taiwan
| | - Hwee-Yeong Ng
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (K.-F.T.); (T.T.-Y.C.); (L.-C.L.); (H.-Y.N.)
| | - Wen-Chin Lee
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (K.-F.T.); (T.T.-Y.C.); (L.-C.L.); (H.-Y.N.)
| | - Chien-Te Lee
- Division of Nephrology, Department of Internal Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung 83301, Taiwan; (K.-F.T.); (T.T.-Y.C.); (L.-C.L.); (H.-Y.N.)
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30
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Fessel J. Does synaptic hypometabolism or synaptic dysfunction, originate cognitive loss? Analysis of the evidence. ALZHEIMER'S & DEMENTIA (NEW YORK, N. Y.) 2021; 7:e12177. [PMID: 34027027 PMCID: PMC8129845 DOI: 10.1002/trc2.12177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 03/31/2021] [Indexed: 11/25/2022]
Abstract
Elderly persons with currently normal cognition who have cerebral hypometabolism as shown by low uptake of 18fluorine-fluorodeoxyglucose (18F-FDG), are at risk of future loss of cognition and, thus, of future Alzheimer's dementia (AD). Reduction of either 18F-FDG or cognition is assumed to reflect synaptic dysfunction, since synapses account for the majority of glucose use by the brain and cognition depends upon accurate synaptic function. The chronology of the connection between reduced cerebral synaptic function and hypometabolism is, therefore, a critical question, because if synaptic dysfunction came first, then correcting the hypometabolism would likely not benefit synaptic function; but if hypometabolism came first, then correcting the hypometabolism probably would benefit synaptic function. That correction might prevent initiation of the cognitive loss that eventuates in AD and, thereby, would benefit the vast numbers of persons in their eighth to tenth decades of life who are at risk for AD. Among the many citations reviewed in this presentation, seven show hypometabolism that precedes synaptic dysfunction, and two show the reverse. Thus the preponderance of evidence, 78%, suggests that the initiating event is synaptic hypometabolism and that it is 3.5-fold less likely that synaptic dysfunction is the initiator. In addition, it is inherently unlikely that synaptic dysfunction causes hypometabolism. This conclusion could be tested by a clinical trial whose primary objective would be to assess the benefit to cognition of improving synaptic metabolism in patients who are at risk for cognitive loss.
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Affiliation(s)
- Jeffrey Fessel
- Department of MedicineUniversity of CaliforniaSan FranciscoCaliforniaUSA
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31
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Rollo I, Gonzalez JT, Fuchs CJ, van Loon LJC, Williams C. Primary, Secondary, and Tertiary Effects of Carbohydrate Ingestion During Exercise. Sports Med 2021; 50:1863-1871. [PMID: 32936440 PMCID: PMC8159838 DOI: 10.1007/s40279-020-01343-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The purpose of this current opinion paper is to describe the journey of ingested carbohydrate from 'mouth to mitochondria' culminating in energy production in skeletal muscles during exercise. This journey is conveniently described as primary, secondary, and tertiary events. The primary stage is detection of ingested carbohydrate by receptors in the oral cavity and on the tongue that activate reward and other centers in the brain leading to insulin secretion. After digestion, the secondary stage is the transport of monosaccharides from the small intestine into the systemic circulation. The passage of these monosaccharides is facilitated by the presence of various transport proteins. The intestinal mucosa has carbohydrate sensors that stimulate the release of two 'incretin' hormones (GIP and GLP-1) whose actions range from the secretion of insulin to appetite regulation. Most of the ingested carbohydrate is taken up by the liver resulting in a transient inhibition of hepatic glucose release in a dose-dependent manner. Nonetheless, the subsequent increased hepatic glucose (and lactate) output can increase exogenous carbohydrate oxidation rates by 40-50%. The recognition and successful distribution of carbohydrate to the brain and skeletal muscles to maintain carbohydrate oxidation as well as prevent hypoglycaemia underpins the mechanisms to improve exercise performance.
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Affiliation(s)
- Ian Rollo
- Gatorade Sports Science Institute, PepsiCo Life Sciences, Global R&D, Leicestershire, UK. .,School of Sports Exercise and Health Sciences, Loughborough University, Loughborough, UK.
| | | | - Cas J Fuchs
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Luc J C van Loon
- Department of Human Biology, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Clyde Williams
- School of Sports Exercise and Health Sciences, Loughborough University, Loughborough, UK
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Abstract
The intranasal (IN) route enables the delivery of insulin to the central nervous system in the relative absence of systemic uptake and related peripheral side effects. Intranasally administered insulin is assumed to travel along olfactory and adjacent pathways and has been shown to rapidly accumulate in cerebrospinal fluid, indicating efficient transport to the brain. Two decades of studies in healthy humans and patients have demonstrated that IN insulin exerts functional effects on metabolism, such as reductions in food intake and body weight and improvements of glucose homeostasis, as well as cognition, ie, enhancements of memory performance both in healthy individuals and patients with mild cognitive impairment or Alzheimer's disease; these studies moreover indicate a favourable safety profile of the acute and repeated use of IN insulin. Emerging findings suggest that IN insulin also modulates neuroendocrine activity, sleep-related mechanisms, sensory perception and mood. Some, but not all studies point to sex differences in the response to IN insulin that need to be further investigated along with the impact of age. "Brain insulin resistance" is an evolving concept that posits impairments in central nervous insulin signalling as a pathophysiological factor in metabolic and cognitive disorders such as obesity, type 2 diabetes and Alzheimer's disease, and, notably, a target of interventions that rely on IN insulin. Still, the negative outcomes of longer-term IN insulin trials in individuals with obesity or Alzheimer's disease highlight the need for conceptual as well as methodological advances to translate the promising results of proof-of-concept experiments and pilot clinical trials into the successful clinical application of IN insulin.
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Affiliation(s)
- Manfred Hallschmid
- Institute of Medical Psychology and Behavioural Neurobiology, University of Tübingen, Tübingen, Germany
- German Centre for Diabetes Research (DZD), Tübingen, Germany
- Institute for Diabetes Research and Metabolic Diseases, Helmholtz Centre Munich at the University of Tübingen, Tübingen, Germany
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33
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Vidal C, Zhang L. An Analysis of the Neurological and Molecular Alterations Underlying the Pathogenesis of Alzheimer's Disease. Cells 2021; 10:cells10030546. [PMID: 33806317 PMCID: PMC7998384 DOI: 10.3390/cells10030546] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 02/26/2021] [Accepted: 03/03/2021] [Indexed: 12/19/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by amyloid beta (Aβ) plaques, neurofibrillary tangles, and neuronal loss. Unfortunately, despite decades of studies being performed on these histological alterations, there is no effective treatment or cure for AD. Identifying the molecular characteristics of the disease is imperative to understanding the pathogenesis of AD. Furthermore, uncovering the key causative alterations of AD can be valuable in developing models for AD treatment. Several alterations have been implicated in driving this disease, including blood–brain barrier dysfunction, hypoxia, mitochondrial dysfunction, oxidative stress, glucose hypometabolism, and altered heme homeostasis. Although these alterations have all been associated with the progression of AD, the root cause of AD has not been identified. Intriguingly, recent studies have pinpointed dysfunctional heme metabolism as a culprit of the development of AD. Heme has been shown to be central in neuronal function, mitochondrial respiration, and oxidative stress. Therefore, dysregulation of heme homeostasis may play a pivotal role in the manifestation of AD and its various alterations. This review will discuss the most common neurological and molecular alterations associated with AD and point out the critical role heme plays in the development of this disease.
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Affiliation(s)
| | - Li Zhang
- Correspondence: ; Tel.: +1-972-883-5757
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34
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Ecker M, Redpath GMI, Nicovich PR, Rossy J. Quantitative visualization of endocytic trafficking through photoactivation of fluorescent proteins. Mol Biol Cell 2021; 32:892-902. [PMID: 33534630 PMCID: PMC8108533 DOI: 10.1091/mbc.e20-10-0669] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Endocytic trafficking controls the density of molecules at the plasma membrane and by doing so, the cell surface profile, which in turn determines how cells interact with their environment. A full apprehension of any cellular process necessitates understanding how proteins associated with the plasma membrane are endocytosed, how they are sorted after internalization, and if and how they are recycled to the plasma membrane. To date, it is still difficult to experimentally gain access to this information, even more to do it in a quantitative way. Here we present a toolset based on photoactivation of fluorescent proteins that enabled us to generate quantitative information on endocytosis, incorporation into sorting and recycling endosomes, delivery from endosomes to the plasma membrane, and on the type of vesicles performing intracellular transport. We illustrate these approaches by revealing striking differences in the endocytic trafficking of T-cell receptor and CD4, which bind to the same molecule at the surface of antigen-presenting cells during T-cell activation.
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Affiliation(s)
- Manuela Ecker
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW 2052, Australia
| | - Gregory M I Redpath
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW 2052, Australia
| | | | - Jérémie Rossy
- EMBL Australia Node in Single Molecule Science, School of Medical Sciences and the ARC Centre of Excellence in Advanced Molecular Imaging, University of New South Wales, Sydney, NSW 2052, Australia.,Biotechnology Institute Thurgau (BITg) at the University of Konstanz, 8280 Kreuzlingen, Switzerland.,Department of Biology, University of Konstanz, 78457 Konstanz, Germany
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35
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Xu XJ, Yang MS, Zhang B, Niu F, Dong JQ, Liu BY. Glucose metabolism: A link between traumatic brain injury and Alzheimer's disease. Chin J Traumatol 2021; 24:5-10. [PMID: 33358332 PMCID: PMC7878452 DOI: 10.1016/j.cjtee.2020.10.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 10/08/2020] [Accepted: 10/15/2020] [Indexed: 02/04/2023] Open
Abstract
Traumatic brain injury (TBI), a growing public health problem, is a leading cause of death and disability worldwide, although its prevention measures and clinical cares are substantially improved. Increasing evidence shows that TBI may increase the risk of mood disorders and neurodegenerative diseases, including Alzheimer's disease (AD). However, the complex relationship between TBI and AD remains elusive. Metabolic dysfunction has been the common pathology in both TBI and AD. On the one hand, TBI perturbs the glucose metabolism of the brain, and causes energy crisis and subsequent hyperglycolysis. On the other hand, glucose deprivation promotes amyloidogenesis via β-site APP cleaving enzyme-1 dependent mechanism, and triggers tau pathology and synaptic function. Recent findings suggest that TBI might facilitate Alzheimer's pathogenesis by altering metabolism, which provides clues to metabolic link between TBI and AD. In this review, we will explore how TBI-induced metabolic changes contribute to the development of AD.
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Affiliation(s)
- Xiao-Jian Xu
- Beijing Key Laboratory of Central Nervous System Injury, Beijing Neurosurgical Institute, Capital Medical University, Beijing, 100070, China
| | - Meng-Shi Yang
- Beijing Key Laboratory of Central Nervous System Injury and Department of Neurosurgery, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Bin Zhang
- Beijing Key Laboratory of Central Nervous System Injury and Department of Neurosurgery, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Fei Niu
- Beijing Key Laboratory of Central Nervous System Injury, Beijing Neurosurgical Institute, Capital Medical University, Beijing, 100070, China
| | - Jin-Qian Dong
- Beijing Key Laboratory of Central Nervous System Injury and Department of Neurosurgery, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Bai-Yun Liu
- Beijing Key Laboratory of Central Nervous System Injury, Beijing Neurosurgical Institute, Capital Medical University, Beijing, 100070, China,Beijing Key Laboratory of Central Nervous System Injury and Department of Neurosurgery, Beijing Neurosurgical Institute and Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China,Nerve Injury and Repair Center of Beijing Institute for Brain Disorders, Beijing, 100070, China,China National Clinical Research Center for Neurological Diseases, Beijing, 100070, China,Corresponding author. Department of Neurosurgery, Beijing Tian Tan Hospital, Capital Medical University, Beijing, 100070, China.
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36
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Abstract
Brain insulin signaling contributes to memory function and might be a viable target in the prevention and treatment of memory impairments including Alzheimer's disease. This short narrative review explores the potential of central nervous system (CNS) insulin administration via the intranasal pathway to improve memory performance in health and disease, with a focus on the most recent results. Proof-of-concept studies and (pilot) clinical trials in individuals with mild cognitive impairment or Alzheimer's disease indicate that acute and prolonged intranasal insulin administration enhances memory performance, and suggest that brain insulin resistance is a pathophysiological factor in Alzheimer's disease with or without concomitant metabolic dysfunction. Intranasally administered insulin is assumed to trigger improvements in synaptic plasticity and regional glucose uptake as well as alleviations of Alzheimer's disease neuropathology; additional contributions of changes in hypothalamus-pituitary-adrenocortical axis activity and sleep-related mechanisms are discussed. While intranasal insulin delivery has been conclusively demonstrated to be effective and safe, the recent outcomes of large-scale clinical studies underline the need for further investigations, which might also yield new insights into sex differences in the response to intranasal insulin and contribute to the optimization of delivery devices to grasp the full potential of intranasal insulin for Alzheimer's disease.
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Affiliation(s)
- Manfred Hallschmid
- Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Otfried-Müller-Str. 25, 72076, Tübingen, Germany.
- German Center for Diabetes Research (DZD), Tübingen, Germany.
- Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany.
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Liao CC, Hou TH, Yu HP, Li A, Liu FC. Cerebrospinal fluid electrolytes and acid-base in diabetic patients. Transl Neurosci 2021; 12:448-455. [PMID: 34804603 PMCID: PMC8578811 DOI: 10.1515/tnsci-2020-0196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/16/2021] [Accepted: 10/20/2021] [Indexed: 12/17/2022] Open
Abstract
Background Diabetes mellitus (DM) has detrimental effects on the function of microvascular beds, resulting in blood–brain barrier (BBB) dysfunction. The objective of the study was to investigate whether DM affects the brain physiology through composition of cerebrospinal fluid (CSF) and compare gas tension and electrolyte levels in CSF between the diabetic and nondiabetic populations. Methods Patients aged between 20 and 70 years scheduled for elective orthopedic or urologic surgery requiring spinal anesthesia were enrolled. They were assigned to either of the two groups (control or type 2 DM). Gas tension and electrolytes in the CSF and whole blood samples were measured in both groups. Results All 49 enrolled patients (24 in the control and 25 in the DM group) completed the study. The concentrations of Na+ and Mg2+ in the blood were significantly lower in the DM group than those in the control. The levels of pCO2 and HCO3−\documentclass[10pt]{article}\usepackage{wasysym}\usepackage[substack]{amsmath}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage[mathscr]{eucal}\usepackage{mathrsfs}\usepackage{pmc}\usepackage[Euler]{upgreek}\pagestyle{empty}\oddsidemargin -1.0in\begin{document}{\text{HCO}}_{3}^{-}]\end{document} in the CSF were lower in the DM group than in the control group. In addition, there was a marked increase in the glucose level in both the blood and CSF in the DM group. Conclusion The results show that there were some homeostatic changes in blood and CSF in patients with DM.
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Affiliation(s)
- Chia-Chih Liao
- Department of Anesthesiology, Chang Gung Memorial Hospital, No. 5, Fushing 1st Rd, Gueishan, Taoyuan 33305, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Te-Hsin Hou
- Department of Anesthesiology, Chang Gung Memorial Hospital, No. 5, Fushing 1st Rd, Gueishan, Taoyuan 33305, Taiwan
| | - Huang-Ping Yu
- Department of Anesthesiology, Chang Gung Memorial Hospital, No. 5, Fushing 1st Rd, Gueishan, Taoyuan 33305, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Allen Li
- Department of Anesthesiology, Chang Gung Memorial Hospital, No. 5, Fushing 1st Rd, Gueishan, Taoyuan 33305, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Fu-Chao Liu
- Department of Anesthesiology, Chang Gung Memorial Hospital, No. 5, Fushing 1st Rd, Gueishan, Taoyuan 33305, Taiwan.,College of Medicine, Chang Gung University, Taoyuan, Taiwan
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38
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Brzecka A, Madetko N, Nikolenko VN, Ashraf GM, Ejma M, Leszek J, Daroszewski C, Sarul K, Mikhaleva LM, Somasundaram SG, Kirkland CE, Bachurin SO, Aliev G. Sleep Disturbances and Cognitive Impairment in the Course of Type 2 Diabetes-A Possible Link. Curr Neuropharmacol 2020; 19:78-91. [PMID: 32148197 PMCID: PMC7903492 DOI: 10.2174/1570159x18666200309101750] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 02/28/2020] [Accepted: 03/05/2020] [Indexed: 02/06/2023] Open
Abstract
There is an increasing number of patients worldwide with sleep disturbances and diabetes. Various sleep disorders, including long or short sleep duration and poor sleep quality of numerous causes, may increase the risk of diabetes. Some symptoms of diabetes, such as painful peripheral neuropathy and nocturia, or associated other sleep disorders, such as sleep breathing disorders or sleep movement disorders, may influence sleep quality and quantity. Both sleep disorders and diabetes may lead to cognitive impairment. The risk of development of cognitive impairment in diabetic patients may be related to vascular and non-vascular and other factors, such as hypoglycemia, hyperglycemia, central insulin resistance, amyloid and tau deposits and other causes. Numerous sleep disorders, e.g., sleep apnea, restless legs syndrome, insomnia, and poor sleep quality are most likely are also associated with cognitive impairment. Adequate functioning of the system of clearance of the brain from toxic substances, such as amyloid β, i.e. glymphatic system, is related to undisturbed sleep and prevents cognitive impairment. In the case of coexistence, sleep disturbances and diabetes either independently lead to and/or mutually aggravate cognitive impairment.
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Affiliation(s)
- Anna Brzecka
- Department of Pulmonology and Lung Cancer, Wroclaw Medical University, Wroclaw, Poland
| | - Natalia Madetko
- Department of Neurology, Wroclaw Medical University, Wroclaw, Poland
| | - Vladimir N Nikolenko
- I. M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University), 8/2 Trubetskaya Str., Moscow, 119991, Russian Federation
| | - Ghulam M Ashraf
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Maria Ejma
- Department of Neurology, Wroclaw Medical University, Wroclaw, Poland
| | - Jerzy Leszek
- Department of Psychiatry, Wroclaw Medical University, Wroclaw, Poland
| | - Cyryl Daroszewski
- Department of Pulmonology and Lung Cancer, Wroclaw Medical University, Wroclaw, Poland
| | - Karolina Sarul
- Department of Pulmonology and Lung Cancer, Wroclaw Medical University, Wroclaw, Poland
| | - Liudmila M Mikhaleva
- Research Institute of Human Morphology,3 Tsyurupy Street, Moscow, 117418, Russian Federation
| | - Siva G Somasundaram
- Department of Biological Sciences, Salem University, Salem, WV, 26426, United States
| | - Cecil E Kirkland
- Department of Biological Sciences, Salem University, Salem, WV, 26426, United States
| | - Sergey O Bachurin
- Institute of Physiologically Active Compounds, Russian Academy of Sciences, Chernogolovka, 142432, Russian Federation
| | - Gjumrakch Aliev
- I. M. Sechenov First Moscow State Medical University of the Ministry of Health of the Russian Federation (Sechenov University), 8/2 Trubetskaya Str., Moscow, 119991, Russian Federation
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39
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Yan X, Hu Y, Wang B, Wang S, Zhang X. Metabolic Dysregulation Contributes to the Progression of Alzheimer's Disease. Front Neurosci 2020; 14:530219. [PMID: 33250703 PMCID: PMC7674854 DOI: 10.3389/fnins.2020.530219] [Citation(s) in RCA: 91] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 09/25/2020] [Indexed: 12/15/2022] Open
Abstract
Alzheimer's disease (AD) is an incurable neurodegenerative disease. Numerous studies have demonstrated a critical role for dysregulated glucose metabolism in its pathogenesis. In this review, we summarize metabolic alterations in aging brain and AD-related metabolic deficits associated with glucose metabolism dysregulation, glycolysis dysfunction, tricarboxylic acid (TCA) cycle, oxidative phosphorylation (OXPHOS) deficits, and pentose phosphate pathway impairment. Additionally, we discuss recent treatment strategies targeting metabolic defects in AD, including their limitations, in an effort to encourage the development of novel therapeutic strategies.
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Affiliation(s)
- Xu Yan
- The VIP Department, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China
| | - Yue Hu
- The VIP Department, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China
| | - Biyao Wang
- The VIP Department, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China
| | - Sijian Wang
- Center of Implant Dentistry, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China
| | - Xinwen Zhang
- Center of Implant Dentistry, School and Hospital of Stomatology, China Medical University, Liaoning Provincial Key Laboratory of Oral Diseases, Shenyang, China
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40
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de Melo IS, Pacheco ALD, Dos Santos YMO, Figueiredo LM, Nicacio DCSP, Cardoso-Sousa L, Duzzioni M, Gitaí DLG, Tilelli CQ, Sabino-Silva R, de Castro OW. Modulation of Glucose Availability and Effects of Hypo- and Hyperglycemia on Status Epilepticus: What We Do Not Know Yet? Mol Neurobiol 2020; 58:505-519. [PMID: 32975651 DOI: 10.1007/s12035-020-02133-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 09/14/2020] [Indexed: 12/22/2022]
Abstract
Status epilepticus (SE) can lead to serious neuronal damage and act as an initial trigger for epileptogenic processes that may lead to temporal lobe epilepsy (TLE). Besides promoting neurodegeneration, neuroinflammation, and abnormal neurogenesis, SE can generate an extensive hypometabolism in several brain areas and, consequently, reduce intracellular energy supply, such as adenosine triphosphate (ATP) molecules. Although some antiepileptic drugs show efficiency to terminate or reduce epileptic seizures, approximately 30% of TLE patients are refractory to regular antiepileptic drugs (AEDs). Modulation of glucose availability may provide a novel and robust alternative for treating seizures and neuronal damage that occurs during epileptogenesis; however, more detailed information remains unknown, especially under hypo- and hyperglycemic conditions. Here, we review several pathways of glucose metabolism activated during and after SE, as well as the effects of hypo- and hyperglycemia in the generation of self-sustained limbic seizures. Furthermore, this study suggests the control of glucose availability as a potential therapeutic tool for SE.
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Affiliation(s)
- Igor Santana de Melo
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil
| | - Amanda Larissa Dias Pacheco
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil
| | - Yngrid Mickaelli Oliveira Dos Santos
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil
| | - Laura Mello Figueiredo
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil
| | - Dannyele Cynthia Santos Pimentel Nicacio
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil
| | - Leia Cardoso-Sousa
- Department of Physiology, Institute of Biomedical Sciences, Federal University of Uberlandia (UFU), ARFIS, Av. Pará, 1720, Campus Umuruama, Uberlandia, MG, CEP 38400-902, Brazil
| | - Marcelo Duzzioni
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil
| | - Daniel Leite Góes Gitaí
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil
| | - Cristiane Queixa Tilelli
- Physiology Laboratory, Federal University of Sao Joao del Rei (UFSJ), Central-West Campus, Divinopolis, MG, Brazil
| | - Robinson Sabino-Silva
- Department of Physiology, Institute of Biomedical Sciences, Federal University of Uberlandia (UFU), ARFIS, Av. Pará, 1720, Campus Umuruama, Uberlandia, MG, CEP 38400-902, Brazil.
| | - Olagide Wagner de Castro
- Department of Physiology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Av. Lourival de Melo Mota, km 14, Campus A. C. Simões, Cidade Universitária, Maceió, AL, CEP 57072-970, Brazil.
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Shippy DC, Ulland TK. Microglial Immunometabolism in Alzheimer's Disease. Front Cell Neurosci 2020; 14:563446. [PMID: 33192310 PMCID: PMC7531234 DOI: 10.3389/fncel.2020.563446] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/28/2020] [Indexed: 12/11/2022] Open
Abstract
Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by amyloid-β (Aβ) plaques and the formation of neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau. In response to Aβ and tau aggregates, microglia, the primary innate immune cells of the central nervous system (CNS), facilitate Aβ and tau clearance and contribute to neuroinflammation that damages neurons. Microglia also perform a wide range of other functions, e.g., synaptic pruning, within the CNS that require a large amount of energy. Glucose appears to be the primary energy source, but microglia can utilize several other substrates for energy production including other sugars and ketone bodies. Recent studies have demonstrated that changes in the metabolic profiles of immune cells, including macrophages, are important in controlling their activation and effector functions. Additional studies have focused on the role of metabolism in neuron and astrocyte function while until recently microglia metabolism has been considerably less well understood. Considering many neurological disorders, such as neurodegeneration associated with AD, are associated with chronic inflammation and alterations in brain energy metabolism, it is hypothesized that microglial metabolism plays a significant role in the inflammatory responses of microglia during neurodegeneration. Here, we review the role of microglial immunometabolism in AD.
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Affiliation(s)
- Daniel C Shippy
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI, United States
| | - Tyler K Ulland
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, WI, United States
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42
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Baron DC, Marko DM, Tsiani E, MacPherson REK. Rosemary extract increases neuronal cell glucose uptake and activates AMPK. Appl Physiol Nutr Metab 2020; 46:141-147. [PMID: 32791009 DOI: 10.1139/apnm-2020-0014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Glucose is the primary metabolic substrate of neurons and is responsible for supporting many vital functions including neuronal signalling. Decreases in glucose uptake and utilization are common characteristics of dementia, particularly Alzheimer's disease, and thus agents that can restore neuronal glucose availability may be especially valuable to the field. Diets rich in antioxidants and polyphenols have been associated with reductions in the risk of chronic disease that are associated with aging. In previous studies, rosemary extract (RE) has been reported to have antioxidant, anti-inflammatory, anticancer, and antidiabetic properties. The purpose of the present study was to explore the effects of RE on neuronal glucose uptake. Human SH-SY5Y neuroblastoma cells exposed to varied concentrations of RE showed a dose-dependent increase in glucose uptake, with a significant increase observed following treatment with 5 µg/mL RE for 2 h (159% ± 20.81% of control) that was comparable to maximum insulin stimulation (135.6% ± 3.2% of control). This increase in glucose uptake was paralleled by increases in AMP-activated protein kinase (AMPK), but not Akt, phosphorylation/activation. The present study is the first to report that treatment with rosemary extract can stimulate glucose uptake in a neuronal cell line. These results demonstrate the potential of RE to be used as an agent to regulate neuronal glucose homeostasis. Novelty: RE increases neuronal glucose uptake. RE activates AMPK in neurons. RE increases neuronal glucose uptake independently of insulin signalling.
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Affiliation(s)
- David C Baron
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Daniel M Marko
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Evangelia Tsiani
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada.,Centre for Bone and Muscle Health, Brock University, St. Catharines, ON L2S 3A1, Canada
| | - Rebecca E K MacPherson
- Department of Health Sciences, Brock University, St. Catharines, ON L2S 3A1, Canada.,Centre for Neuroscience, Brock University, St. Catharines, ON L2S 3A1, Canada
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43
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Bouvier ML, Fehsel K, Schmitt A, Meisenzahl-Lechner E, Gaebel W, von Wilmsdorff M. Sex-dependent alterations of dopamine receptor and glucose transporter density in rat hypothalamus under long-term clozapine and haloperidol medication. Brain Behav 2020; 10:e01694. [PMID: 32525610 PMCID: PMC7428470 DOI: 10.1002/brb3.1694] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/04/2020] [Indexed: 12/25/2022] Open
Abstract
OBJECTIVE Sex-dependent disturbances of peripheral glucose metabolism are known complications of antipsychotic drug treatment. The influence of long-term clozapine and haloperidol medication on hypothalamus, maintaining aspects of internal body homeostasis, has not yet been completely clarified. METHODS After puberty, male and female Sprague Dawley rats were fed orally with ground pellets containing haloperidol (1 mg/kgBW/day) or clozapine (20 mg/kgBW/day) for 12 weeks. The hypothalamic protein expression of dopamine receptors D2R and D4R, melanocortin receptor MC4R, and glucose transporters Glut1 and Glut3 was examined. Glucose, glycogen, lactate, and pyruvate levels were determined, also malondialdehyde equivalents as markers of oxidative stress. RESULTS D2R expression was increased in the male haloperidol and clozapine group but decreased in females medicated with clozapine. D4R expression was upregulated under clozapine medication. While females showed increased Glut1, Glut3 was elevated in both male and female clozapine-medicated animals. We found no changes of hypothalamic malondialdehyde, glycogen, and MC4R. Hypothalamic lactate was elevated in the female clozapine group. CONCLUSION Clozapine sex-dependently affects the expression of D2R, Glut1, and Glut3. The upregulation of the glucose transporters indicates glucose deprivation in the endothelial cells and consequently in astrocytes and neurons. Increased hypothalamic lactate in females under clozapine points to enhanced glycolysis with a higher glucose demand to produce the required energy. Haloperidol did not change the expression of the glucose transporters and upregulated D2R only in males.
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Affiliation(s)
- Marie-Luise Bouvier
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Karin Fehsel
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Andrea Schmitt
- Department of Psychiatry and Psychotherapy, University Hospital, Ludwig-Maximilians University Munich, München, Germany.,Laboratory of Neuroscience (LIM27), Institute of Psychiatry, University of Sao Paulo, São Paulo, Brazil
| | - Eva Meisenzahl-Lechner
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Wolfgang Gaebel
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Martina von Wilmsdorff
- Department of Psychiatry and Psychotherapy, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
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44
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Pifferi F, Cunnane SC, Guesnet P. Evidence of the Role of Omega-3 Polyunsaturated Fatty Acids in Brain Glucose Metabolism. Nutrients 2020; 12:nu12051382. [PMID: 32408634 PMCID: PMC7285025 DOI: 10.3390/nu12051382] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 05/11/2020] [Accepted: 05/11/2020] [Indexed: 11/30/2022] Open
Abstract
In mammals, brain function, particularly neuronal activity, has high energy needs. When glucose is supplemented by alternative oxidative substrates under different physiological conditions, these fuels do not fully replace the functions fulfilled by glucose. Thus, it is of major importance that the brain is almost continuously supplied with glucose from the circulation. Numerous studies describe the decrease in brain glucose metabolism during healthy or pathological ageing, but little is known about the mechanisms that cause such impairment. Although it appears difficult to determine the exact role of brain glucose hypometabolism during healthy ageing or during age-related neurodegenerative diseases such as Alzheimer’s disease, uninterrupted glucose supply to the brain is still of major importance for proper brain function. Interestingly, a body of evidence suggests that dietary n-3 polyunsaturated fatty acids (PUFAs) might play significant roles in brain glucose regulation. Thus, the goal of the present review is to summarize this evidence and address the role of n-3 PUFAs in brain energy metabolism. Taken together, these data suggest that ensuring an adequate dietary supply of n-3 PUFAs could constitute an essential aspect of a promising strategy to promote optimal brain function during both healthy and pathological ageing.
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Affiliation(s)
- Fabien Pifferi
- Unité Mixte de Recherche (UMR), Centre Nationnal de la Recherche Scientifique (CNRS), Museum National d’Histoire Naturelle (MNHN) 7179, Mécanismes Adaptatifs et Evolution (MECADEV), 1 Avenue du Petit Château, 91800 Brunoy, France
- Correspondence:
| | - Stephen C. Cunnane
- Department of Medicine, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada;
- Research Center on Aging, Sherbrooke, QC J1H 4C4, Canada
- Department of Pharmacology and Physiology, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada
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Rajagopal N, Irudayanathan FJ, Nangia S. Computational Nanoscopy of Tight Junctions at the Blood-Brain Barrier Interface. Int J Mol Sci 2019; 20:E5583. [PMID: 31717316 PMCID: PMC6888702 DOI: 10.3390/ijms20225583] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 11/05/2019] [Accepted: 11/06/2019] [Indexed: 12/16/2022] Open
Abstract
The selectivity of the blood-brain barrier (BBB) is primarily maintained by tight junctions (TJs), which act as gatekeepers of the paracellular space by blocking blood-borne toxins, drugs, and pathogens from entering the brain. The BBB presents a significant challenge in designing neurotherapeutics, so a comprehensive understanding of the TJ architecture can aid in the design of novel therapeutics. Unraveling the intricacies of TJs with conventional experimental techniques alone is challenging, but recently developed computational tools can provide a valuable molecular-level understanding of TJ architecture. We employed the computational methods toolkit to investigate claudin-5, a highly expressed TJ protein at the BBB interface. Our approach started with the prediction of claudin-5 structure, evaluation of stable dimer conformations and nanoscale assemblies, followed by the impact of lipid environments, and posttranslational modifications on these claudin-5 assemblies. These led to the study of TJ pores and barriers and finally understanding of ion and small molecule transport through the TJs. Some of these in silico, molecular-level findings, will need to be corroborated by future experiments. The resulting understanding can be advantageous towards the eventual goal of drug delivery across the BBB. This review provides key insights gleaned from a series of state-of-the-art nanoscale simulations (or computational nanoscopy studies) performed on the TJ architecture.
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Affiliation(s)
| | | | - Shikha Nangia
- Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, NY 13244, USA
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46
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Barrio JR, Huang SC, Satyamurthy N, Scafoglio CS, Yu AS, Alavi A, Krohn KA. Does 2-FDG PET Accurately Reflect Quantitative In Vivo Glucose Utilization? J Nucl Med 2019; 61:931-937. [PMID: 31676728 DOI: 10.2967/jnumed.119.237446] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 10/22/2019] [Indexed: 12/29/2022] Open
Abstract
2-Deoxy-2-18F-fluoro-d-glucose (2-FDG) with PET is undeniably useful in the clinic, being able, among other uses, to monitor change over time using the 2-FDG SUV metric. This report suggests some potentially serious caveats for this and related roles for 2-FDG PET. Most critical is the assumption that there is an exact proportionality between glucose metabolism and 2-FDG metabolism, called the lumped constant, or LC. This report describes that LC is not constant for a specific tissue and may be variable before and after disease treatment. The purpose of this work is not to deny the clinical value of 2-FDG PET; it is a reminder that when one extends the use of an appropriately qualified imaging method, new observations may arise and further validation would be necessary. The current understanding of glucose-based energetics in vivo is based on the quantification of glucose metabolic rates with 2-FDG PET, a method that permits the noninvasive assessment of various human disorders. However, 2-FDG is a good substrate only for facilitated-glucose transporters (GLUTs), not for sodium-dependent glucose cotransporters (SGLTs), which have recently been shown to be distributed in multiple human tissues. Thus, the GLUT-mediated in vivo glucose utilization measured by 2-FDG PET would be masked to the potentially substantial role of functional SGLTs in glucose transport and use. Therefore, under these circumstances, the 2-FDG LC used to quantify in vivo glucose utilization should not be expected to remain constant. 2-FDG LC variations have been especially significant in tumors, particularly at different stages of cancer development, affecting the accuracy of quantitative glucose measures and potentially limiting the prognostic value of 2-FDG, as well as its accuracy in monitoring treatments. SGLT-mediated glucose transport can be estimated using α-methyl-4-deoxy-4-18F-fluoro-d-glucopyranoside (Me-4FDG). Using both 2-FDG and Me-4FDG should provide a more complete picture of glucose utilization via both GLUT and SGLT transporters in health and disease states. Given the widespread use of 2-FDG PET to infer glucose metabolism, it is relevant to appreciate the potential limitations of 2-FDG as a surrogate for glucose metabolic rate and the potential reasons for variability in LC. Even when the readout for the 2-FDG PET study is only an SUV parameter, variability in LC is important, particularly if it changes over the course of disease progression (e.g., an evolving tumor).
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Affiliation(s)
- Jorge R Barrio
- Department of Molecular and Medical Pharmacology, David Geffen UCLA School of Medicine, Los Angeles, California
| | - Sung-Cheng Huang
- Department of Molecular and Medical Pharmacology, David Geffen UCLA School of Medicine, Los Angeles, California
| | - Nagichettiar Satyamurthy
- Department of Molecular and Medical Pharmacology, David Geffen UCLA School of Medicine, Los Angeles, California
| | - Claudio S Scafoglio
- Department of Medicine, David Geffen UCLA School of Medicine, Los Angeles, California
| | - Amy S Yu
- Department of Molecular and Medical Pharmacology, David Geffen UCLA School of Medicine, Los Angeles, California
| | - Abass Alavi
- University of Pennsylvania, Philadelphia, Pennsylvania; and
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Spinelli M, Fusco S, Grassi C. Brain Insulin Resistance and Hippocampal Plasticity: Mechanisms and Biomarkers of Cognitive Decline. Front Neurosci 2019; 13:788. [PMID: 31417349 PMCID: PMC6685093 DOI: 10.3389/fnins.2019.00788] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 07/15/2019] [Indexed: 12/27/2022] Open
Abstract
In the last decade, much attention has been devoted to the effects of nutrient-related signals on brain development and cognitive functions. A turning point was the discovery that brain areas other than the hypothalamus expressed receptors for hormones related to metabolism. In particular, insulin signaling has been demonstrated to impact on molecular cascades underlying hippocampal plasticity, learning and memory. Here, we summarize the molecular evidence linking alteration of hippocampal insulin sensitivity with changes of both adult neurogenesis and synaptic plasticity. We also review the epidemiological studies and experimental models emphasizing the critical role of brain insulin resistance at the crossroad between metabolic and neurodegenerative disease. Finally, we brief novel findings suggesting how biomarkers of brain insulin resistance, involving the study of brain-derived extracellular vesicles and brain glucose metabolism, may predict the onset and/or the progression of cognitive decline.
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Affiliation(s)
- Matteo Spinelli
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Salvatore Fusco
- Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
| | - Claudio Grassi
- Institute of Human Physiology, Università Cattolica del Sacro Cuore, Rome, Italy.,Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
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Descalzi G, Gao V, Steinman MQ, Suzuki A, Alberini CM. Lactate from astrocytes fuels learning-induced mRNA translation in excitatory and inhibitory neurons. Commun Biol 2019; 2:247. [PMID: 31286064 PMCID: PMC6606643 DOI: 10.1038/s42003-019-0495-2] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Accepted: 06/05/2019] [Indexed: 12/12/2022] Open
Abstract
Glycogenolysis and lactate transport from astrocytes to neurons is required for long-term memory formation, but the role of this lactate is poorly understood. Here we show that the Krebs cycle substrates pyruvate and ketone body B3HB can functionally replace lactate in rescuing memory impairment caused by inhibition of glycogenolysis or expression knockdown of glia monocarboxylate transporters (MCTs) 1 and 4 in the dorsal hippocampus of rats. In contrast, either metabolite is unable to rescue memory impairment produced by expression knockdown of MCT2, which is selectively expressed by neurons, indicating that a critical role of astrocytic lactate is to provide energy for neuronal responses required for long-term memory. These responses include learning-induced mRNA translation in both excitatory and inhibitory neurons, as well as expression of Arc/Arg3.1. Thus, astrocytic lactate acts as an energy substrate to fuel learning-induced de novo neuronal translation critical for long-term memory.
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Affiliation(s)
- Giannina Descalzi
- Center for Neural Science, New York University, New York, NY 10003 USA
| | - Virginia Gao
- Center for Neural Science, New York University, New York, NY 10003 USA
| | | | - Akinobu Suzuki
- Center for Neural Science, New York University, New York, NY 10003 USA
- Present Address: Department of Biochemistry, Faculty of Medicine, Graduate School of Medicine & Pharmaceutical Sciences, University of Toyama, 2630 Sugitani, Toyama, 930-0194 Japan
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Kiyatkin EA. Respiratory depression and brain hypoxia induced by opioid drugs: Morphine, oxycodone, heroin, and fentanyl. Neuropharmacology 2019; 151:219-226. [PMID: 30735692 DOI: 10.1016/j.neuropharm.2019.02.008] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 01/30/2019] [Accepted: 02/04/2019] [Indexed: 12/27/2022]
Abstract
Opioid drugs are important tools to alleviate pain of different origins, but they have strong addictive potential and their abuse at higher doses often results in serious health complications. Respiratory depression that leads to brain hypoxia is perhaps the most dangerous symptom of acute intoxication with opioids, and it could result in lethality. The development of substrate-specific sensors coupled with amperometry made it possible to directly evaluate physiological and drug-induced fluctuations in brain oxygen levels in awake, freely-moving rats. The goal of this review paper is to consider changes in brain oxygen levels induced by several opioid drugs (heroin, fentanyl, oxycodone, morphine). While some of these drugs are widely used in clinical practice, they all are abused, often at doses exceeding the clinical range and often resulting in serious health complications. First, we consider some basic knowledge regarding brain oxygen, its physiological fluctuations, and mechanisms involved in regulating its entry into brain tissue. Then, we present and discuss data on brain oxygen changes induced by each opioid drug within a wide range of doses, from low, behaviorally relevant, to high, likely to be self-administered by drug users. These data allowed us to compare the effects of these drugs on brain oxygen in terms of their potency, time-course, and their potential danger when used at high doses via rapid-onset administration routes. While most data discussed in this work were obtained in rats, we believe that these data have clear human relevance in addressing the alarming rise in lethality associated with the opioid abuse.
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Affiliation(s)
- Eugene A Kiyatkin
- Behavioral Neuroscience Branch, National Institute on Drug Abuse - Intramural Research Program, National Institute of Health, DHHS, 333 Cassell Drive, Baltimore, MD, 21224, USA.
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Agrawal A, Pekkurnaz G, Koslover EF. Spatial control of neuronal metabolism through glucose-mediated mitochondrial transport regulation. eLife 2018; 7:40986. [PMID: 30561333 PMCID: PMC6322862 DOI: 10.7554/elife.40986] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 12/17/2018] [Indexed: 01/01/2023] Open
Abstract
Eukaryotic cells modulate their metabolism by organizing metabolic components in response to varying nutrient availability and energy demands. In rat axons, mitochondria respond to glucose levels by halting active transport in high glucose regions. We employ quantitative modeling to explore physical limits on spatial organization of mitochondria and localized metabolic enhancement through regulated stopping of processive motion. We delineate the role of key parameters, including cellular glucose uptake and consumption rates, that are expected to modulate mitochondrial distribution and metabolic response in spatially varying glucose conditions. Our estimates indicate that physiological brain glucose levels fall within the limited range necessary for metabolic enhancement. Hence mitochondrial localization is shown to be a plausible regulatory mechanism for neuronal metabolic flexibility in the presence of spatially heterogeneous glucose, as may occur in long processes of projection neurons. These findings provide a framework for the control of cellular bioenergetics through organelle trafficking. Cells are equipped with power factories called mitochondria that turn nutrients into chemical energy to fuel processes in the cell. Hundreds of mitochondria move throughout the cell, shifting their positions in response to energy demands. This happens via molecular motors that pick the mitochondria up and carry them to new locations. Such movements enable the mitochondria to accumulate in parts of the cell with the greatest energy needs. Mitochondria of nerve cells or neurons have a particular challenging job, as neurons can be very long and different parts within the cells can have different energy needs. It has been shown that mitochondria stop in regions where nutrients such as sugar are most concentrated. So far, it has been unclear whether this regulated stopping helps control energy balance in neurons. Here, Agrawal et al. used a computational model of rat neurons to find out whether sugar levels are sufficient in guiding mitochondria. The results showed that the mitochondria only accumulated in high-nutrient regions when the sugar concentrations were moderate – not too low and not too high. A specific range of sugar levels was necessary to make this mechanism useful for increasing the efficiency of energy production. Such concentrations match the ones observed in healthy rat brains. When neurons are unable to meet their energy demands, they stop working and sometimes even die. This is the case in many diseases, including diabetes, dementia, and Alzheimer’s disease. Computer models allow us to explore the complex energy regulation in detail. A better understanding of how neurons regulate their energy production and demand may help us discover how they become faulty in these diseases.
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Affiliation(s)
- Anamika Agrawal
- Department of Physics, University of California, San Diego, San Diego, United States
| | - Gulcin Pekkurnaz
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, San Diego, United States
| | - Elena F Koslover
- Department of Physics, University of California, San Diego, San Diego, United States
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