1
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Fernandes MGF, Pernin F, Antel JP, Kennedy TE. From BBB to PPP: Bioenergetic requirements and challenges for oligodendrocytes in health and disease. J Neurochem 2024. [PMID: 39253904 DOI: 10.1111/jnc.16219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2024] [Revised: 06/24/2024] [Accepted: 08/08/2024] [Indexed: 09/11/2024]
Abstract
Mature myelinating oligodendrocytes, the cells that produce the myelin sheath that insulates axons in the central nervous system, have distinct energetic and metabolic requirements compared to neurons. Neurons require substantial energy to execute action potentials, while the energy needs of oligodendrocytes are directed toward building the lipid-rich components of myelin and supporting neuronal metabolism by transferring glycolytic products to axons as additional fuel. The utilization of energy metabolites in the brain parenchyma is tightly regulated to meet the needs of different cell types. Disruption of the supply of metabolites can lead to stress and oligodendrocyte injury, contributing to various neurological disorders, including some demyelinating diseases. Understanding the physiological properties, structures, and mechanisms involved in oligodendrocyte energy metabolism, as well as the relationship between oligodendrocytes and neighboring cells, is crucial to investigate the underlying pathophysiology caused by metabolic impairment in these disorders. In this review, we describe the particular physiological properties of oligodendrocyte energy metabolism and the response of oligodendrocytes to metabolic stress. We delineate the relationship between oligodendrocytes and other cells in the context of the neurovascular unit, and the regulation of metabolite supply according to energetic needs. We focus on the specific bioenergetic requirements of oligodendrocytes and address the disruption of metabolic energy in demyelinating diseases. We encourage further studies to increase understanding of the significance of metabolic stress on oligodendrocyte injury, to support the development of novel therapeutic approaches for the treatment of demyelinating diseases.
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Affiliation(s)
- Milton Guilherme Forestieri Fernandes
- Neuroimmunological Diseases and Glia Biology Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Florian Pernin
- Neuroimmunological Diseases and Glia Biology Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Jack P Antel
- Neuroimmunological Diseases and Glia Biology Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Timothy E Kennedy
- Neuroimmunological Diseases and Glia Biology Research Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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2
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Shen K, Shi Y, Wang X, Leung SW. Cellular Components of the Blood-Brain Barrier and Their Involvement in Aging-Associated Cognitive Impairment. Aging Dis 2024:AD.202.0424. [PMID: 39122454 DOI: 10.14336/ad.202.0424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Accepted: 07/01/2024] [Indexed: 08/12/2024] Open
Abstract
Human life expectancy has been significantly extended, which poses major challenges to our healthcare and social systems. Aging-associated cognitive impairment is attributed to endothelial dysfunction in the cardiovascular system and neurological dysfunction in the central nervous system. The central nervous system is considered an immune-privileged tissue due to the exquisite protection provided by the blood-brain barrier. The present review provides an overview of the structure and function of blood-brain barrier, extending the cell components of blood-brain barrier from endothelial cells and pericytes to astrocytes, perivascular macrophages and oligodendrocyte progenitor cells. In particular, the pathological changes in the blood-brain barrier in aging, with special focus on the underlying mechanisms and molecular changes, are presented. Furthermore, the potential preventive/therapeutic strategies against aging-associated blood-brain barrier disruption are discussed.
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Affiliation(s)
- Kaiyuan Shen
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yi Shi
- Institute of Clinical Science, Zhongshan Hospital, Fudan University, Shanghai, China
- Key Laboratory of Organ Transplantation, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Xin Wang
- Department of Neurology, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Susan Ws Leung
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
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3
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Oliveira A, Azevedo M, Seixas R, Martinho R, Serrão P, Moreira-Rodrigues M. Glucose may Contribute to Retrieval and Reconsolidation of Contextual Fear Memory Through Hippocampal Nr4a3 and Bdnf mRNA Expression and May Act Synergically with Adrenaline. Mol Neurobiol 2024; 61:2784-2797. [PMID: 37938511 PMCID: PMC11043124 DOI: 10.1007/s12035-023-03745-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 10/27/2023] [Indexed: 11/09/2023]
Abstract
Adrenaline (Ad) and glucose released into the bloodstream during stress may strengthen contextual fear memory. However, no previous studies have detached the effects of glucose from Ad in this paradigm. Using Ad-deficient mice, we aimed to evaluate the effect of glucose on contextual fear memory when endogenous Ad is absent. Fear conditioning was performed in wild-type (WT) and Ad-deficient mice (129 × 1/SvJ) administered with glucose (30 or 10 mg/kg; i.p.) or/and Ad (0.01 mg/kg; i.p.) or vehicle (0.9% NaCl; i.p.). Catecholamines were quantified using HPLC-ED. Real-time qPCR was used to assess mRNA expression of hippocampal genes. WT and Ad-deficient mice display increased contextual fear memory when administered with glucose both in acquisition and context days when compared to vehicle. Also, Nr4a3 and Bdnf mRNA expression increased in glucose-administered Ad-deficient mice. Sub-effective doses of glucose plus Ad administered simultaneously to Ad-deficient mice increased contextual fear memory, contrary to independent sub-effective doses. Concluding, glucose may be an important part of the peripheral to central pathway involved in the retrieval and reconsolidation of fear contextual memories independently of Ad, possibly due to increased hippocampal Nr4a3 and Bdnf gene expression. Furthermore, Ad and glucose may act synergically to strengthen contextual fear memory.
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Affiliation(s)
- Ana Oliveira
- Department of Immuno-physiology and Pharmacology, Laboratory of General Physiology, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (UP), R. Jorge Viterbo Ferreira, 228, Building 2, Floor 4, Cabinet 22, Porto, 4050-313, Portugal
- Center for Drug Discovery and Innovative Medicines, University of Porto (MedInUP), Porto, Portugal
| | - Márcia Azevedo
- Department of Immuno-physiology and Pharmacology, Laboratory of General Physiology, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (UP), R. Jorge Viterbo Ferreira, 228, Building 2, Floor 4, Cabinet 22, Porto, 4050-313, Portugal
- Center for Drug Discovery and Innovative Medicines, University of Porto (MedInUP), Porto, Portugal
| | - Rafaela Seixas
- Department of Immuno-physiology and Pharmacology, Laboratory of General Physiology, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (UP), R. Jorge Viterbo Ferreira, 228, Building 2, Floor 4, Cabinet 22, Porto, 4050-313, Portugal
- Center for Drug Discovery and Innovative Medicines, University of Porto (MedInUP), Porto, Portugal
| | - Raquel Martinho
- Department of Immuno-physiology and Pharmacology, Laboratory of General Physiology, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (UP), R. Jorge Viterbo Ferreira, 228, Building 2, Floor 4, Cabinet 22, Porto, 4050-313, Portugal
- Center for Drug Discovery and Innovative Medicines, University of Porto (MedInUP), Porto, Portugal
| | - Paula Serrão
- Center for Drug Discovery and Innovative Medicines, University of Porto (MedInUP), Porto, Portugal
- Department of Biomedicine, Faculty of Medicine, University of Porto (FMUP), Porto, Portugal
| | - Mónica Moreira-Rodrigues
- Department of Immuno-physiology and Pharmacology, Laboratory of General Physiology, School of Medicine and Biomedical Sciences (ICBAS), University of Porto (UP), R. Jorge Viterbo Ferreira, 228, Building 2, Floor 4, Cabinet 22, Porto, 4050-313, Portugal.
- Center for Drug Discovery and Innovative Medicines, University of Porto (MedInUP), Porto, Portugal.
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Abstract
The brain is a complex organ, fundamentally changing across the day to perform basic functions like sleep, thought, and regulating whole-body physiology. This requires a complex symphony of nutrients, hormones, ions, neurotransmitters and more to be properly distributed across the brain to maintain homeostasis throughout 24 hours. These solutes are distributed both by the blood and by cerebrospinal fluid. Cerebrospinal fluid contents are distinct from the general circulation because of regulation at brain barriers including the choroid plexus, glymphatic system, and blood-brain barrier. In this review, we discuss the overlapping circadian (≈24-hour) rhythms in brain fluid biology and at the brain barriers. Our goal is for the reader to gain both a fundamental understanding of brain barriers alongside an understanding of the interactions between these fluids and the circadian timing system. Ultimately, this review will provide new insight into how alterations in these finely tuned clocks may lead to pathology.
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Affiliation(s)
- Velia S Vizcarra
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
| | - Ryann M Fame
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Lauren M Hablitz
- Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, NY, 14642, USA
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Simon Machado R, Mathias K, Joaquim L, Willig de Quadros R, Petronilho F, Tezza Rezin G. From diabetic hyperglycemia to cerebrovascular Damage: A narrative review. Brain Res 2023; 1821:148611. [PMID: 37793604 DOI: 10.1016/j.brainres.2023.148611] [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: 07/13/2023] [Revised: 09/04/2023] [Accepted: 09/28/2023] [Indexed: 10/06/2023]
Abstract
Diabetes mellitus is a globally significant disease that can lead to systemic complications, particularly vascular damage, including cardiovascular and cerebrovascular diseases of relevance. The physiological changes resulting from the imbalance in blood glucose levels play a crucial role in initiating vascular endothelial damage. Elevated glucose levels can also penetrate the central nervous system, triggering diabetic encephalopathy characterized by oxidative damage to brain components and activation of alternative and neurotoxic pathways. This brain damage increases the risk of ischemic stroke, a leading cause of mortality worldwide and a major cause of disability among surviving patients. The aim of this review is to highlight important pathways related to hyperglycemic damage that extend to the brain and result in vascular dysfunction, ultimately leading to the occurrence of a stroke. Understanding how diabetes mellitus contributes to the development of ischemic stroke and its impact on patient outcomes is crucial for implementing therapeutic strategies that reduce the incidence of diabetes mellitus and its complications, ultimately decreasing morbidity and mortality associated with the disease.
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Affiliation(s)
- Richard Simon Machado
- Laboratory of Experimental Neurology, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciuma, SC, Brazil; Laboratory of Neurobiology of Inflammatory and Metabolic Processes, Graduate Program in Health Sciences, Health Sciences Unit, University of South Santa Catarina, Tubarão, SC, Brazil.
| | - Khiany Mathias
- Laboratory of Experimental Neurology, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciuma, SC, Brazil
| | - Larissa Joaquim
- Laboratory of Experimental Neurology, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciuma, SC, Brazil
| | - Rafaella Willig de Quadros
- Laboratory of Experimental Neurology, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciuma, SC, Brazil
| | - Fabricia Petronilho
- Laboratory of Experimental Neurology, Graduate Program in Health Sciences, Health Sciences Unit, University of Southern Santa Catarina, Criciuma, SC, Brazil
| | - Gislaine Tezza Rezin
- Laboratory of Neurobiology of Inflammatory and Metabolic Processes, Graduate Program in Health Sciences, Health Sciences Unit, University of South Santa Catarina, Tubarão, SC, Brazil
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Kotchetkov P, Blakeley N, Lacoste B. Involvement of brain metabolism in neurodevelopmental disorders. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2023; 173:67-113. [PMID: 37993180 DOI: 10.1016/bs.irn.2023.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2023]
Abstract
Neurodevelopmental disorders (NDDs) affect a significant portion of the global population and have a substantial social and economic impact worldwide. Most NDDs manifest in early childhood and are characterized by deficits in cognition, communication, social interaction and motor control. Due to a limited understanding of the etiology of NDDs, current treatment options primarily focus on symptom management rather than on curative solutions. Moreover, research on NDDs is problematic due to its reliance on a neurocentric approach. However, recent studies are broadening the scope of research on NDDs, to include dysregulations within a diverse network of brain cell types, including vascular and glial cells. This review aims to summarize studies from the past few decades on potential new contributions to the etiology of NDDs, with a special focus on metabolic signatures of various brain cells. In particular, we aim to convey how the metabolic functions are intimately linked to the onset and/or progression of common NDDs such as autism spectrum disorders, fragile X syndrome, Rett syndrome and Down syndrome.
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Affiliation(s)
- Pavel Kotchetkov
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Nicole Blakeley
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Baptiste Lacoste
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Cellular & Molecular Medicine, University of Ottawa, Ottawa, ON, Canada; University of Ottawa Brain and Mind Research Institute, Ottawa, ON, Canada.
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7
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Wątroba M, Grabowska AD, Szukiewicz D. Effects of Diabetes Mellitus-Related Dysglycemia on the Functions of Blood-Brain Barrier and the Risk of Dementia. Int J Mol Sci 2023; 24:10069. [PMID: 37373216 DOI: 10.3390/ijms241210069] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 06/11/2023] [Accepted: 06/12/2023] [Indexed: 06/29/2023] Open
Abstract
Diabetes mellitus is one of the most common metabolic diseases worldwide, and its long-term complications include neuropathy, referring both to the peripheral and to the central nervous system. Detrimental effects of dysglycemia, especially hyperglycemia, on the structure and function of the blood-brain barrier (BBB), seem to be a significant backgrounds of diabetic neuropathy pertaining to the central nervous system (CNS). Effects of hyperglycemia, including excessive glucose influx to insulin-independent cells, may induce oxidative stress and secondary innate immunity dependent inflammatory response, which can damage cells within the CNS, thus promoting neurodegeneration and dementia. Advanced glycation end products (AGE) may exert similar, pro-inflammatory effects through activating receptors for advanced glycation end products (RAGE), as well as some pattern-recognition receptors (PRR). Moreover, long-term hyperglycemia can promote brain insulin resistance, which may in turn promote Aβ aggregate accumulation and tau hyperphosphorylation. This review is focused on a detailed analysis of the effects mentioned above towards the CNS, with special regard to mechanisms taking part in the pathogenesis of central long-term complications of diabetes mellitus initiated by the loss of BBB integrity.
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Affiliation(s)
- Mateusz Wątroba
- Laboratory of the Blood-Brain Barrier, Department of Biophysics, Physiology & Pathophysiology, Medical University of Warsaw, Chałubinskiego 5, 02-004 Warsaw, Poland
| | - Anna D Grabowska
- Laboratory of the Blood-Brain Barrier, Department of Biophysics, Physiology & Pathophysiology, Medical University of Warsaw, Chałubinskiego 5, 02-004 Warsaw, Poland
| | - Dariusz Szukiewicz
- Laboratory of the Blood-Brain Barrier, Department of Biophysics, Physiology & Pathophysiology, Medical University of Warsaw, Chałubinskiego 5, 02-004 Warsaw, Poland
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8
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The role of the blood-brain barrier during neurological disease and infection. Biochem Soc Trans 2023; 51:613-626. [PMID: 36929707 DOI: 10.1042/bst20220830] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/18/2023]
Abstract
A healthy brain is protected by the blood-brain barrier (BBB), which is formed by the endothelial cells that line brain capillaries. The BBB plays an extremely important role in supporting normal neuronal function by maintaining the homeostasis of the brain microenvironment and restricting pathogen and toxin entry to the brain. Dysfunction of this highly complex and regulated structure can be life threatening. BBB dysfunction is implicated in many neurological diseases such as stroke, Alzheimer's disease, multiple sclerosis, and brain infections. Among other mechanisms, inflammation and/or flow disturbances are major causes of BBB dysfunction in neurological infections and diseases. In particular, in ischaemic stroke, both inflammation and flow disturbances contribute to BBB disruption, leading to devastating consequences. While a transient or minor disruption to the barrier function could be tolerated, chronic or a total breach of the barrier can result in irreversible brain damage. It is worth noting that timing and extent of BBB disruption play an important role in the process of any repair of brain damage and treatment strategies. This review evaluates and summarises some of the latest research on the role of the BBB during neurological disease and infection with a focus on the effects of inflammation and flow disturbances on the BBB. The BBB's crucial role in protecting the brain is also the bottleneck in central nervous system drug development. Therefore, innovative strategies to carry therapeutics across the BBB and novel models to screen drugs, and to study the complex, overlapping mechanisms of BBB disruption are urgently needed.
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Nakayama-Kitamura K, Shigemoto-Mogami Y, Toyoda H, Mihara I, Moriguchi H, Naraoka H, Furihata T, Ishida S, Sato K. Usefulness of a humanized tricellular static transwell blood-brain barrier model as a microphysiological system for drug development applications. - A case study based on the benchmark evaluations of blood-brain barrier microphysiological system. Regen Ther 2023; 22:192-202. [PMID: 36891355 PMCID: PMC9988422 DOI: 10.1016/j.reth.2023.02.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/21/2023] [Accepted: 02/08/2023] [Indexed: 03/06/2023] Open
Abstract
Microphysiological system (MPS), a new technology for in vitro testing platforms, have been acknowledged as a strong tool for drug development. In the central nervous system (CNS), the blood‒brain barrier (BBB) limits the permeation of circulating substances from the blood vessels to the brain, thereby protecting the CNS from circulating xenobiotic compounds. At the same time, the BBB hinders drug development by introducing challenges at various stages, such as pharmacokinetics/pharmacodynamics (PK/PD), safety assessment, and efficacy assessment. To solve these problems, efforts are being made to develop a BBB MPS, particularly of a humanized type. In this study, we suggested minimal essential benchmark items to establish the BBB-likeness of a BBB MPS; these criteria support end users in determining the appropriate range of applications for a candidate BBB MPS. Furthermore, we examined these benchmark items in a two-dimensional (2D) humanized tricellular static transwell BBB MPS, the most conventional design of BBB MPS with human cell lines. Among the benchmark items, the efflux ratios of P-gp and BCRP showed high reproducibility in two independent facilities, while the directional transports meditated through Glut1 or TfR were not confirmed. We have organized the protocols of the experiments described above as standard operating procedures (SOPs). We here provide the SOPs with the flow chart including entire procedure and how to apply each SOP. Our study is important developmental step of BBB MPS towards the social acceptance, which enable end users to check and compare the performance the BBB MPSs.
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Key Words
- BBB, blood-brain barrier
- BCRP
- BCRP, Breast cancer resistance protein
- Blood‒brain barrier (BBB)
- CNS, central nervous system
- Glut1, Glucose transporter 1
- HASTR, Human astrocytes
- HBMEC, Human brain microvascular endothelial cells
- HBPC, Human brain pericyte
- LC-MS/MS, Liquid chromatography with tandem mass spectrometry
- LY, Lucifer yellow
- MPS, Microphysiological system
- Microphysiological system (MPS)
- P-gp
- P-gp, P-glycoprotein
- TEER, Trans-endothelial electrical resistance
- TfR, Transferrin receptor
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Affiliation(s)
- Kimiko Nakayama-Kitamura
- Laboratory of Neuropharmacology, Division of Pharmacology, National Institute of Health Science, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki City, Kanagawa, Japan
| | - Yukari Shigemoto-Mogami
- Laboratory of Neuropharmacology, Division of Pharmacology, National Institute of Health Science, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki City, Kanagawa, Japan
| | - Hiroko Toyoda
- Stem Cell Evaluation Technology Research Association, Grande Building 8F, 2-26-9 Hatchobori, Chuo-ku, Tokyo 104-0032, Japan
| | - Ikue Mihara
- Stem Cell Evaluation Technology Research Association, Grande Building 8F, 2-26-9 Hatchobori, Chuo-ku, Tokyo 104-0032, Japan
| | - Hiroyuki Moriguchi
- Stem Cell Evaluation Technology Research Association, Grande Building 8F, 2-26-9 Hatchobori, Chuo-ku, Tokyo 104-0032, Japan
| | - Hitoshi Naraoka
- Stem Cell Evaluation Technology Research Association, Grande Building 8F, 2-26-9 Hatchobori, Chuo-ku, Tokyo 104-0032, Japan
| | - Tomomi Furihata
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 Japan
| | - Seiichi Ishida
- Laboratory of Neuropharmacology, Division of Pharmacology, National Institute of Health Science, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki City, Kanagawa, Japan.,Division of Applied Life Science, Graduate School of Engineering, Sojo University, 4-22-1 Ikeda, Nishi-ku, Kumamoto City, Kumamoto, Japan
| | - Kaoru Sato
- Laboratory of Neuropharmacology, Division of Pharmacology, National Institute of Health Science, 3-25-26 Tonomachi, Kawasaki-ku, Kawasaki City, Kanagawa, Japan
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Phukan BC, Roy R, Paul R, Mazumder MK, Nath J, Bhattacharya P, Borah A. Traversing through the cell signaling pathways of neuroprotection by betanin: therapeutic relevance to Alzheimer's Disease and Parkinson's Disease. Metab Brain Dis 2023; 38:805-817. [PMID: 36745251 DOI: 10.1007/s11011-023-01177-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/23/2023] [Indexed: 02/07/2023]
Abstract
Modulation of cell signaling pathways is the key area of research towards the treatment of neurodegenerative disorders. Altered Nrf2-Keap1-ARE (Nuclear factor erythroid-2-related factor 2-Kelch-like ECH-associated protein 1-Antioxidant responsive element) and SIRT1 (Sirtuin 1) cell signaling pathways are considered to play major role in the etiology and pathogenesis of Alzheimer's disease (AD) and Parkinson's disease (PD). Strikingly, betanin, a betanidin 5-O-β-D-glucoside compound is reported to show commendable anti-oxidative, anti-inflammatory and anti-apoptotic effects in several disease studies including AD and PD. The present review discusses the pre-clinical studies demonstrating the neuroprotective effects of betanin by virtue of its potential to ameliorate oxidative stress, neuroinflammation, abnormal protein aggregation and cell death. It highlights the direct linkage between the neuroprotective abilities of betanin and upregulation of the Nrf2-Keap1-ARE and SIRT1 signaling pathways. The review further hypothesizes the involvement of the betanin-Nrf2-ARE route in the inhibition of beta-amyloid aggregation through beta-site amyloid precursor protein cleaving enzyme 1 (BACE1), one of the pivotal hallmarks of AD. The present review hereby for the first time elaborately discusses the reported neuroprotective abilities of betanin and decodes the Nrf2 and SIRT1 modulating potential of betanin as a primary mechanism of action behind, hence highlighting it as a novel drug candidate for the treatment of neurodegenerative diseases in the near future.
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Affiliation(s)
- Banashree Chetia Phukan
- Cellular and Molecular Neurobiology Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India, 788011
| | - Rubina Roy
- Cellular and Molecular Neurobiology Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India, 788011
| | - Rajib Paul
- Department of Zoology, Pandit Deendayal Upadhyaya Adarsha Mahavidyalaya (PDUAM), Eraligool, Karimganj, Assam, India, 788723
| | | | - Joyobrato Nath
- Department of Zoology, Cachar College, Silchar, Assam, India, 788001
| | - Pallab Bhattacharya
- Department of Pharmacology and Toxicology, National Institute of Pharmaceutical Education and Research (NIPER), Ahmedabad, 382355, Gandhinagar, Gujarat, India
| | - Anupom Borah
- Cellular and Molecular Neurobiology Laboratory, Department of Life Science and Bioinformatics, Assam University, Silchar, Assam, India, 788011.
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11
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Mantecón-Oria M, Rivero MJ, Diban N, Urtiaga A. On the quest of reliable 3D dynamic in vitro blood-brain barrier models using polymer hollow fiber membranes: Pitfalls, progress, and future perspectives. Front Bioeng Biotechnol 2022; 10:1056162. [PMID: 36483778 PMCID: PMC9723404 DOI: 10.3389/fbioe.2022.1056162] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 11/07/2022] [Indexed: 09/10/2024] Open
Abstract
With the increasing concern of neurodegenerative diseases, the development of new therapies and effective pharmaceuticals targeted to central nervous system (CNS) illnesses is crucial for ensuring social and economic sustainability in an ageing world. Unfortunately, many promising treatments at the initial stages of the pharmaceutical development process, that is at the in vitro screening stages, do not finally show the expected results at the clinical level due to their inability to cross the human blood-brain barrier (BBB), highlighting the inefficiency of in vitro BBB models to recapitulate the real functionality of the human BBB. In the last decades research has focused on the development of in vitro BBB models from basic 2D monolayer cultures to 3D cell co-cultures employing different system configurations. Particularly, the use of polymeric hollow fiber membranes (HFs) as scaffolds plays a key role in perfusing 3D dynamic in vitro BBB (DIV-BBB) models. Their incorporation into a perfusion bioreactor system may potentially enhance the vascularization and oxygenation of 3D cell cultures improving cell communication and the exchange of nutrients and metabolites through the microporous membranes. The quest for developing a benchmark 3D dynamic in vitro blood brain barrier model requires the critical assessment of the different aspects that limits the technology. This article will focus on identifying the advantages and main limitations of the HFs in terms of polymer materials, microscopic porous morphology, and other practical issues that play an important role to adequately mimic the physiological environment and recapitulate BBB architecture. Based on this study, we consider that future strategic advances of this technology to become fully implemented as a gold standard DIV-BBB model will require the exploration of novel polymers and/or composite materials, and the optimization of the morphology of the membranes towards thinner HFs (<50 μm) with higher porosities and surface pore sizes of 1-2 µm to facilitate the intercommunication via regulatory factors between the cell co-culture models of the BBB.
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Affiliation(s)
- Marián Mantecón-Oria
- Departamento de Ingenierias Química y Biomolecular, Universidad de Cantabria, Santander, Spain
- Instituto Marqués de Valdecilla (IDIVAL), Santander, Spain
| | - María J. Rivero
- Departamento de Ingenierias Química y Biomolecular, Universidad de Cantabria, Santander, Spain
| | - Nazely Diban
- Departamento de Ingenierias Química y Biomolecular, Universidad de Cantabria, Santander, Spain
- Instituto Marqués de Valdecilla (IDIVAL), Santander, Spain
| | - Ane Urtiaga
- Departamento de Ingenierias Química y Biomolecular, Universidad de Cantabria, Santander, Spain
- Instituto Marqués de Valdecilla (IDIVAL), Santander, Spain
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12
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Sato Y, Falcone-Juengert J, Tominaga T, Su H, Liu J. Remodeling of the Neurovascular Unit Following Cerebral Ischemia and Hemorrhage. Cells 2022; 11:2823. [PMID: 36139398 PMCID: PMC9496956 DOI: 10.3390/cells11182823] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 08/18/2022] [Accepted: 08/30/2022] [Indexed: 11/23/2022] Open
Abstract
Formulated as a group effort of the stroke community, the transforming concept of the neurovascular unit (NVU) depicts the structural and functional relationship between brain cells and the vascular structure. Composed of both neural and vascular elements, the NVU forms the blood-brain barrier that regulates cerebral blood flow to meet the oxygen demand of the brain in normal physiology and maintain brain homeostasis. Conversely, the dysregulation and dysfunction of the NVU is an essential pathological feature that underlies neurological disorders spanning from chronic neurodegeneration to acute cerebrovascular events such as ischemic stroke and cerebral hemorrhage, which were the focus of this review. We also discussed how common vascular risk factors of stroke predispose the NVU to pathological changes. We synthesized existing literature and first provided an overview of the basic structure and function of NVU, followed by knowledge of how these components remodel in response to ischemic stroke and brain hemorrhage. A greater understanding of the NVU dysfunction and remodeling will enable the design of targeted therapies and provide a valuable foundation for relevant research in this area.
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Affiliation(s)
- Yoshimichi Sato
- Department of Neurological Surgery, UCSF, San Francisco, CA 94158, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA 94158, USA
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
| | - Jaime Falcone-Juengert
- Department of Neurological Surgery, UCSF, San Francisco, CA 94158, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA 94158, USA
| | - Teiji Tominaga
- Department of Neurosurgery, Graduate School of Medicine, Tohoku University, 1-1 Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan
| | - Hua Su
- Department of Anesthesia, UCSF, San Francisco, CA 94143, USA
- Center for Cerebrovascular Research, UCSF, San Francisco, CA 94143, USA
| | - Jialing Liu
- Department of Neurological Surgery, UCSF, San Francisco, CA 94158, USA
- Department of Neurological Surgery, SFVAMC, San Francisco, CA 94158, USA
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13
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Abstract
The central nervous system (CNS) has been viewed as an immunologically privileged site, but emerging works are uncovering a large array of neuroimmune interactions primarily occurring at its borders. CNS barriers sites host diverse population of both innate and adaptive immune cells capable of, directly and indirectly, influence the function of the residing cells of the brain parenchyma. These structures are only starting to reveal their role in controlling brain function under normal and pathological conditions and represent an underexplored therapeutic target for the treatment of brain disorders. This review will highlight the development of the CNS barriers to host neuro-immune interactions and emphasize their newly described roles in neurodevelopmental, neurological, and neurodegenerative disorders, particularly for the meninges.
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Affiliation(s)
- Natalie M Frederick
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Gabriel A Tavares
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Antoine Louveau
- Department of Neurosciences, Lerner Research Institute, Cleveland Clinic, Cleveland, Ohio, USA.,Department of Molecular Medicine, Cleveland Clinic College of Medicine, Case Western Reserve University, Cleveland, Ohio, USA.,Kent University, Neurosciences, School of Biomedical Sciences, Cleveland, Ohio, USA
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14
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Mir M, Palma-Florez S, Lagunas A, López-Martínez MJ, Samitier J. Biosensors Integration in Blood-Brain Barrier-on-a-Chip: Emerging Platform for Monitoring Neurodegenerative Diseases. ACS Sens 2022; 7:1237-1247. [PMID: 35559649 PMCID: PMC9150172 DOI: 10.1021/acssensors.2c00333] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
![]()
Over the most recent
decades, the development of new biological
platforms to study disease progression and drug efficacy has been
of great interest due to the high increase in the rate of neurodegenerative
diseases (NDDs). Therefore, blood–brain barrier (BBB) as an
organ-on-a-chip (OoC) platform to mimic brain-barrier performance
could offer a deeper understanding of NDDs as well as a very valuable
tool for drug permeability testing for new treatments. A very attractive
improvement of BBB-oC technology is the integration of detection systems
to provide continuous monitoring of biomarkers in real time and a
fully automated analysis of drug permeably, rendering more efficient
platforms for commercialization. In this Perspective, an overview
of the main BBB-oC configurations is introduced and a critical vision
of the BBB-oC platforms integrating electronic read out systems is
detailed, indicating the strengths and weaknesses of current devices,
proposing the great potential for biosensors integration in BBB-oC.
In this direction, we name potential biomarkers to monitor the evolution
of NDDs related to the BBB and/or drug cytotoxicity using biosensor
technology in BBB-oC.
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Affiliation(s)
- Mònica Mir
- Biomedical Research Networking Center in Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN) Monforte de Lemos 3-5, Pabellón 11, 28029 Madrid, Spain
- Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), 12 Baldiri Reixac 15-21, Barcelona 08028, Spain
- Department of Electronics and Biomedical Engineering, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Sujey Palma-Florez
- Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), 12 Baldiri Reixac 15-21, Barcelona 08028, Spain
- Department of Electronics and Biomedical Engineering, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Anna Lagunas
- Biomedical Research Networking Center in Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN) Monforte de Lemos 3-5, Pabellón 11, 28029 Madrid, Spain
- Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), 12 Baldiri Reixac 15-21, Barcelona 08028, Spain
| | - Maria José López-Martínez
- Biomedical Research Networking Center in Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN) Monforte de Lemos 3-5, Pabellón 11, 28029 Madrid, Spain
- Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), 12 Baldiri Reixac 15-21, Barcelona 08028, Spain
- Department of Electronics and Biomedical Engineering, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Josep Samitier
- Biomedical Research Networking Center in Bioengineering, Biomaterials, and Nanomedicine (CIBER-BBN) Monforte de Lemos 3-5, Pabellón 11, 28029 Madrid, Spain
- Nanobioengineering Group, Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), 12 Baldiri Reixac 15-21, Barcelona 08028, Spain
- Department of Electronics and Biomedical Engineering, University of Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
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15
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Immediate Early Gene c-fos in the Brain: Focus on Glial Cells. Brain Sci 2022; 12:brainsci12060687. [PMID: 35741573 PMCID: PMC9221432 DOI: 10.3390/brainsci12060687] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 05/18/2022] [Accepted: 05/19/2022] [Indexed: 12/13/2022] Open
Abstract
The c-fos gene was first described as a proto-oncogene responsible for the induction of bone tumors. A few decades ago, activation of the protein product c-fos was reported in the brain after seizures and other noxious stimuli. Since then, multiple studies have used c-fos as a brain activity marker. Although it has been attributed to neurons, growing evidence demonstrates that c-fos expression in the brain may also include glial cells. In this review, we collect data showing that glial cells also express this proto-oncogene. We present evidence demonstrating that at least astrocytes, oligodendrocytes, and microglia express this immediate early gene (IEG). Unlike neurons, whose expression changes used to be associated with depolarization, glial cells seem to express the c-fos proto-oncogene under the influence of proliferation, differentiation, growth, inflammation, repair, damage, plasticity, and other conditions. The collected evidence provides a complementary view of c-fos as an activity marker and urges the introduction of the glial cell perspective into brain activity studies. This glial cell view may provide additional information related to the brain microenvironment that is difficult to obtain from the isolated neuron paradigm. Thus, it is highly recommended that detection techniques are improved in order to better differentiate the phenotypes expressing c-fos in the brain and to elucidate the specific roles of c-fos expression in glial cells.
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16
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Blood-Brain Barrier Transporters: Opportunities for Therapeutic Development in Ischemic Stroke. Int J Mol Sci 2022; 23:ijms23031898. [PMID: 35163820 PMCID: PMC8836701 DOI: 10.3390/ijms23031898] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/02/2022] [Accepted: 02/04/2022] [Indexed: 12/20/2022] Open
Abstract
Globally, stroke is a leading cause of death and long-term disability. Over the past decades, several efforts have attempted to discover new drugs or repurpose existing therapeutics to promote post-stroke neurological recovery. Preclinical stroke studies have reported successes in identifying novel neuroprotective agents; however, none of these compounds have advanced beyond a phase III clinical trial. One reason for these failures is the lack of consideration of blood-brain barrier (BBB) transport mechanisms that can enable these drugs to achieve efficacious concentrations in ischemic brain tissue. Despite the knowledge that drugs with neuroprotective properties (i.e., statins, memantine, metformin) are substrates for endogenous BBB transporters, preclinical stroke research has not extensively studied the role of transporters in central nervous system (CNS) drug delivery. Here, we review current knowledge on specific BBB uptake transporters (i.e., organic anion transporting polypeptides (OATPs in humans; Oatps in rodents); organic cation transporters (OCTs in humans; Octs in rodents) that can be targeted for improved neuroprotective drug delivery. Additionally, we provide state-of-the-art perspectives on how transporter pharmacology can be integrated into preclinical stroke research. Specifically, we discuss the utility of in vivo stroke models to transporter studies and considerations (i.e., species selection, co-morbid conditions) that will optimize the translational success of stroke pharmacotherapeutic experiments.
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17
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Leung SWS, Shi Y. The glycolytic process in endothelial cells and its implications. Acta Pharmacol Sin 2022; 43:251-259. [PMID: 33850277 PMCID: PMC8791959 DOI: 10.1038/s41401-021-00647-y] [Citation(s) in RCA: 52] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Accepted: 02/22/2021] [Indexed: 02/06/2023] Open
Abstract
Endothelial cells play an obligatory role in regulating local vascular tone and maintaining homeostasis in vascular biology. Cell metabolism, converting food to energy in organisms, is the primary self-sustaining mechanism for cell proliferation and reproduction, structure maintenance, and fight-or-flight responses to stimuli. Four major metabolic processes take place in the energy-producing process, including glycolysis, oxidative phosphorylation, glutamine metabolism, and fatty acid oxidation. Among them, glycolysis is the primary energy-producing mechanism in endothelial cells. The present review focused on glycolysis in endothelial cells under both physiological and pathological conditions. Since the switches among metabolic processes precede the functional changes and disease developments, some prophylactic and/or therapeutic strategies concerning the role of glycolysis in cardiovascular disease are discussed.
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Affiliation(s)
- Susan, Wai Sum Leung
- grid.194645.b0000000121742757Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China
| | - Yi Shi
- grid.8547.e0000 0001 0125 2443Institute of Clinical Science, Zhongshan Hospital, Fudan University, Shanghai, 200032 China ,grid.8547.e0000 0001 0125 2443Key Laboratory of Organ Transplantation, Zhongshan Hospital, Fudan University, Shanghai, 200032 China
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18
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Ljubimov VA, Ramesh A, Davani S, Danielpour M, Breunig JJ, Black KL. Neurosurgery at the crossroads of immunology and nanotechnology. New reality in the COVID-19 pandemic. Adv Drug Deliv Rev 2022; 181:114033. [PMID: 34808227 PMCID: PMC8604570 DOI: 10.1016/j.addr.2021.114033] [Citation(s) in RCA: 2] [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: 09/06/2021] [Revised: 10/19/2021] [Accepted: 10/28/2021] [Indexed: 12/12/2022]
Abstract
Neurosurgery as one of the most technologically demanding medical fields rapidly adapts the newest developments from multiple scientific disciplines for treating brain tumors. Despite half a century of clinical trials, survival for brain primary tumors such as glioblastoma (GBM), the most common primary brain cancer, or rare ones including primary central nervous system lymphoma (PCNSL), is dismal. Cancer therapy and research have currently shifted toward targeted approaches, and personalized therapies. The orchestration of novel and effective blood-brain barrier (BBB) drug delivery approaches, targeting of cancer cells and regulating tumor microenvironment including the immune system are the key themes of this review. As the global pandemic due to SARS-CoV-2 virus continues, neurosurgery and neuro-oncology must wrestle with the issues related to treatment-related immune dysfunction. The selection of chemotherapeutic treatments, even rare cases of hypersensitivity reactions (HSRs) that occur among immunocompromised people, and number of vaccinations they have to get are emerging as a new chapter for modern Nano neurosurgery.
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Affiliation(s)
- Vladimir A Ljubimov
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA.
| | | | | | - Moise Danielpour
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Joshua J Breunig
- Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Keith L Black
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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19
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20
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Costa YPD, Freitas-Júnior C, Lima-Júnior DD, Soares-Silva EL, Batista GR, Hayes L, Fortes LDS. Mental fatigue and ball sports: a narrative review focused on physical, technical, and tactical performance. MOTRIZ: REVISTA DE EDUCACAO FISICA 2022. [DOI: 10.1590/s1980-657420220004822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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21
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The Blood-Brain Barrier: Much More Than a Selective Access to the Brain. Neurotox Res 2021; 39:2154-2174. [PMID: 34677787 DOI: 10.1007/s12640-021-00431-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 09/30/2021] [Accepted: 10/15/2021] [Indexed: 12/15/2022]
Abstract
The blood-brain barrier is a dynamic structure, collectively referred to as the neurovascular unit. It is responsible for the exchange of blood, oxygen, ions, and other molecules between the peripheral circulation and the brain compartment. It is the main entrance to the central nervous system and as such critical for the maintenance of its homeostasis. Dysfunction of the blood-brain barrier is a characteristic of several neurovascular pathologies. Moreover, physiological changes, environmental factors, nutritional habits, and psychological stress can modulate the tightness of the barrier. In this contribution, we summarize our current understanding of structure and function of this important component of the brain. We also describe the neurological deficits associated with its damage. A special emphasis is placed in the effect of the exposure to xenobiotics and pollutants in the permeability of the barrier. Finally, current protective strategies as well as the culture models to study this fascinating structure are discussed.
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22
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Kugler EC, Greenwood J, MacDonald RB. The "Neuro-Glial-Vascular" Unit: The Role of Glia in Neurovascular Unit Formation and Dysfunction. Front Cell Dev Biol 2021; 9:732820. [PMID: 34646826 PMCID: PMC8502923 DOI: 10.3389/fcell.2021.732820] [Citation(s) in RCA: 84] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/01/2021] [Indexed: 12/15/2022] Open
Abstract
The neurovascular unit (NVU) is a complex multi-cellular structure consisting of endothelial cells (ECs), neurons, glia, smooth muscle cells (SMCs), and pericytes. Each component is closely linked to each other, establishing a structural and functional unit, regulating central nervous system (CNS) blood flow and energy metabolism as well as forming the blood-brain barrier (BBB) and inner blood-retina barrier (BRB). As the name suggests, the “neuro” and “vascular” components of the NVU are well recognized and neurovascular coupling is the key function of the NVU. However, the NVU consists of multiple cell types and its functionality goes beyond the resulting neurovascular coupling, with cross-component links of signaling, metabolism, and homeostasis. Within the NVU, glia cells have gained increased attention and it is increasingly clear that they fulfill various multi-level functions in the NVU. Glial dysfunctions were shown to precede neuronal and vascular pathologies suggesting central roles for glia in NVU functionality and pathogenesis of disease. In this review, we take a “glio-centric” view on NVU development and function in the retina and brain, how these change in disease, and how advancing experimental techniques will help us address unanswered questions.
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Affiliation(s)
- Elisabeth C Kugler
- Institute of Ophthalmology, Faculty of Brain Sciences, University College London, London, United Kingdom
| | - John Greenwood
- Institute of Ophthalmology, Faculty of Brain Sciences, University College London, London, United Kingdom
| | - Ryan B MacDonald
- Institute of Ophthalmology, Faculty of Brain Sciences, University College London, London, United Kingdom
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23
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Kim MH, Kim D, Sung JH. A Gut-Brain Axis-on-a-Chip for studying transport across epithelial and endothelial barriers. J IND ENG CHEM 2021. [DOI: 10.1016/j.jiec.2021.06.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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24
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Gonzalez-Resines S, Quinn PJ, Naftalin RJ, Domene C. Multiple Interactions of Glucose with the Extra-Membranous Loops of GLUT1 Aid Transport. J Chem Inf Model 2021; 61:3559-3570. [PMID: 34260246 DOI: 10.1021/acs.jcim.1c00310] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Molecular dynamics simulations amounting to ≈8 μs demonstrate that the glucose transporter GLUT1 undergoes structural fluctuations mediated by the fluidity of the lipid bilayer and the proximity to glucose. The fluctuations of GLUT1 increase as the glucose concentration is raised. These fluctuations are more pronounced when the lipid bilayer is in the fluid compared to the gel phase. Glucose interactions are confined to the extra-membranous residues when the lipid is in the gel phase but diffuses into the transmembrane regions in the fluid phase. Proximity of glucose to GLUT1 causes asynchronous expansions of key bottlenecks at the internal and external openings of the central pore. This is accomplished only by small conformational changes at the single residue level that lower the resistance to glucose movements, thereby permitting unsteered glucose and water movements along the entire length of the pore. When glucose is near salt bridges located at the external and internal openings of the central pore, the distance separating the polar amino acid residues guarding these apertures tends to increase in both fluid and gel phases. It is evident that the multiplicity of glucose interactions, obtained with high concentrations, amplifies the structural fluctuations in GLUT1. The findings that most of the salt bridges and the bottlenecks appear to be operated by glucose proximity suggest that the main triggers to activation of transport are located within the solvent accessible linker regions in the extramembranous zones.
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Affiliation(s)
| | - Peter J Quinn
- Department of Biochemistry, King's College London, London WC2R 2LS, U.K
| | - Richard J Naftalin
- BHF Centre of Research Excellence, School of Medicine and Life Sciences, King's College London, London WC2R 2LS, U.K
| | - Carmen Domene
- Departments of Chemistry, University of Bath, Bath BA2 7AX, U.K.,Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, U.K
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25
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Rojas M, Chávez-Castillo M, Bautista J, Ortega Á, Nava M, Salazar J, Díaz-Camargo E, Medina O, Rojas-Quintero J, Bermúdez V. Alzheimer’s disease and type 2 diabetes mellitus: Pathophysiologic and pharmacotherapeutics links. World J Diabetes 2021; 12:745-766. [PMID: 34168725 PMCID: PMC8192246 DOI: 10.4239/wjd.v12.i6.745] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Revised: 03/20/2021] [Accepted: 05/21/2021] [Indexed: 02/06/2023] Open
Abstract
At present, Alzheimer’s disease (AD) and type 2 diabetes mellitus (T2DM) are two highly prevalent disorders worldwide, especially among elderly individuals. T2DM appears to be associated with cognitive dysfunction, with a higher risk of developing neurocognitive disorders, including AD. These diseases have been observed to share various pathophysiological mechanisms, including alterations in insulin signaling, defects in glucose transporters (GLUTs), and mitochondrial dysfunctions in the brain. Therefore, the aim of this review is to summarize the current knowledge regarding the molecular mechanisms implicated in the association of these pathologies as well as recent therapeutic alternatives. In this context, the hyperphosphorylation of tau and the formation of neurofibrillary tangles have been associated with the dysfunction of the phosphatidylinositol 3-kinase and mitogen-activated protein kinase pathways in the nervous tissues as well as the decrease in the expression of GLUT-1 and GLUT-3 in the different areas of the brain, increase in reactive oxygen species, and production of mitochondrial alterations that occur in T2DM. These findings have contributed to the implementation of overlapping pharmacological interventions based on the use of insulin and antidiabetic drugs, or, more recently, azeliragon, amylin, among others, which have shown possible beneficial effects in diabetic patients diagnosed with AD.
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Affiliation(s)
- Milagros Rojas
- Endocrine and Metabolic Diseases Research Center, School of Medicine, University of Zulia, Maracaibo 4004, Venezuela
| | - Mervin Chávez-Castillo
- Endocrine and Metabolic Diseases Research Center, School of Medicine, University of Zulia, Maracaibo 4004, Venezuela
| | - Jordan Bautista
- Endocrine and Metabolic Diseases Research Center, School of Medicine, University of Zulia, Maracaibo 4004, Venezuela
| | - Ángel Ortega
- Endocrine and Metabolic Diseases Research Center, School of Medicine, University of Zulia, Maracaibo 4004, Venezuela
| | - Manuel Nava
- Endocrine and Metabolic Diseases Research Center, School of Medicine, University of Zulia, Maracaibo 4004, Venezuela
| | - Juan Salazar
- Endocrine and Metabolic Diseases Research Center, School of Medicine, University of Zulia, Maracaibo 4004, Venezuela
| | - Edgar Díaz-Camargo
- Universidad Simón Bolívar, Facultad de Ciencias Jurídicas y Sociales, Cúcuta 540006, Colombia
| | - Oscar Medina
- Universidad Simón Bolívar, Facultad de Ciencias Jurídicas y Sociales, Cúcuta 540006, Colombia
| | - Joselyn Rojas-Quintero
- Pulmonary and Critical Care Medicine Department, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02155, United States
| | - Valmore Bermúdez
- Universidad Simón Bolívar, Facultad de Ciencias de la Salud, Barranquilla 080001, Colombia
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26
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Seo S, Choi CH, Yi KS, Kim SU, Lee K, Choi N, Lee HJ, Cha SH, Kim HN. An engineered neurovascular unit for modeling neuroinflammation. Biofabrication 2021; 13. [PMID: 33849004 DOI: 10.1088/1758-5090/abf741] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 04/13/2021] [Indexed: 12/25/2022]
Abstract
The neurovascular unit (NVU) comprises multiple types of brain cells, including brain endothelial cells, astrocytes, pericytes, neurons, microglia, and oligodendrocytes. Each cell type contributes to the maintenance of the molecular transport barrier and brain tissue homeostasis. Several disorders and diseases of the central nervous system, including neuroinflammation, Alzheimer's disease, stroke, and multiple sclerosis, have been associated with dysfunction of the NVU. As a result, there has been increased demand for the development of NVUin vitromodels. Here, we present a three-dimensional (3D) immortalized human cell-based NVU model generated by organizing the brain microvasculature in a collagen matrix embedded with six different types of cells that comprise the NVU. By surrounding a perfusable brain endothelium with six types of NVU-composing cells, we demonstrated a significant impact of the 3D co-culture on the maturation of barrier function, which is supported by cytokines secreted from NVU-composing cells. Furthermore, NVU-composing cells alleviated the inflammatory responses induced by lipopolysaccharides. Our human cell-based NVUin vitromodel could enable elucidation of both physiological and pathological mechanisms in the human brain and evaluation of safety and efficacy in the context of high-content analysis during the process of drug development.
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Affiliation(s)
- Suyeong Seo
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Republic of Korea.,These authors contributed equally to this work
| | - Chi-Hoon Choi
- Department of Radiology, Chung Buk National University Hospital, Cheongju, Chung Buk, Republic of Korea.,College of Medicine, Chung Buk National University, Cheongju, Chung Buk 28644, Republic of Korea.,These authors contributed equally to this work
| | - Kyung Sik Yi
- Department of Radiology, Chung Buk National University Hospital, Cheongju, Chung Buk, Republic of Korea
| | - Seung U Kim
- Division of Neurology, Department of Medicine, UBC Hospital, University of British Columbia, Vancouver, BC, Canada
| | - Kangwon Lee
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Seoul 08826, Republic of Korea
| | - Nakwon Choi
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea.,KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Republic of Korea
| | - Hong Jun Lee
- College of Medicine, Chung Buk National University, Cheongju, Chung Buk 28644, Republic of Korea.,Research Institute, eBiogen Inc., Seoul, Republic of Korea
| | - Sang-Hoon Cha
- Department of Radiology, Chung Buk National University Hospital, Cheongju, Chung Buk, Republic of Korea.,College of Medicine, Chung Buk National University, Cheongju, Chung Buk 28644, Republic of Korea
| | - Hong Nam Kim
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Republic of Korea.,Division of Bio-Medical Science and Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea
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27
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Patabendige A, Singh A, Jenkins S, Sen J, Chen R. Astrocyte Activation in Neurovascular Damage and Repair Following Ischaemic Stroke. Int J Mol Sci 2021; 22:4280. [PMID: 33924191 PMCID: PMC8074612 DOI: 10.3390/ijms22084280] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 04/11/2021] [Accepted: 04/15/2021] [Indexed: 12/11/2022] Open
Abstract
Transient or permanent loss of tissue perfusion due to ischaemic stroke can lead to damage to the neurovasculature, and disrupt brain homeostasis, causing long-term motor and cognitive deficits. Despite promising pre-clinical studies, clinically approved neuroprotective therapies are lacking. Most studies have focused on neurons while ignoring the important roles of other cells of the neurovascular unit, such as astrocytes and pericytes. Astrocytes are important for the development and maintenance of the blood-brain barrier, brain homeostasis, structural support, control of cerebral blood flow and secretion of neuroprotective factors. Emerging data suggest that astrocyte activation exerts both beneficial and detrimental effects following ischaemic stroke. Activated astrocytes provide neuroprotection and contribute to neurorestoration, but also secrete inflammatory modulators, leading to aggravation of the ischaemic lesion. Astrocytes are more resistant than other cell types to stroke pathology, and exert a regulative effect in response to ischaemia. These roles of astrocytes following ischaemic stroke remain incompletely understood, though they represent an appealing target for neurovascular protection following stroke. In this review, we summarise the astrocytic contributions to neurovascular damage and repair following ischaemic stroke, and explore mechanisms of neuroprotection that promote revascularisation and neurorestoration, which may be targeted for developing novel therapies for ischaemic stroke.
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Affiliation(s)
- Adjanie Patabendige
- Brain Barriers Group, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2321, Australia;
- Priority Research Centre for Stroke and Brain Injury, and Priority Research Centre for Brain & Mental Health, University of Newcastle, Callaghan, NSW 2321, Australia
- Hunter Medical Research Institute, New Lambton Heights, NSW 2305, Australia
- Institute of Infection & Global Health, University of Liverpool, Liverpool L7 3EA, UK
| | - Ayesha Singh
- School of Pharmacy and Bioengineering, Keele University, Staffordshire ST5 5BG, UK;
| | - Stuart Jenkins
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (S.J.); (J.S.)
- Neural Tissue Engineering: Keele (NTEK), Keele University, Staffordshire ST5 5BG, UK
| | - Jon Sen
- School of Medicine, Keele University, Staffordshire ST5 5BG, UK; (S.J.); (J.S.)
- Clinical Informatics and Neurosurgery Fellow, The Cleveland Clinic, 33 Grosvenor Square, London SW1X 7HY, UK
| | - Ruoli Chen
- School of Pharmacy and Bioengineering, Keele University, Staffordshire ST5 5BG, UK;
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Weber CM, Clyne AM. Sex differences in the blood-brain barrier and neurodegenerative diseases. APL Bioeng 2021; 5:011509. [PMID: 33758788 PMCID: PMC7968933 DOI: 10.1063/5.0035610] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 02/03/2021] [Indexed: 02/06/2023] Open
Abstract
The number of people diagnosed with neurodegenerative diseases is on the rise. Many of these diseases, including Alzheimer's disease, Parkinson's disease, multiple sclerosis, and motor neuron disease, demonstrate clear sexual dimorphisms. While sex as a biological variable must now be included in animal studies, sex is rarely included in in vitro models of human neurodegenerative disease. In this Review, we describe these sex-related differences in neurodegenerative diseases and the blood-brain barrier (BBB), whose dysfunction is linked to neurodegenerative disease development and progression. We explain potential mechanisms by which sex and sex hormones affect BBB integrity. Finally, we summarize current in vitro BBB bioengineered models and highlight their potential to study sex differences in BBB integrity and neurodegenerative disease.
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Affiliation(s)
- Callie M Weber
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, USA
| | - Alisa Morss Clyne
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland 20742, USA
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Li J, Huang J, He Y, Wang W, Leung CK, Zhang D, Zhang R, Wang S, Li Y, Liu L, Zeng X, Li Z. The protective effect of gastrodin against the synergistic effect of HIV-Tat protein and METH on the blood-brain barrier via glucose transporter 1 and glucose transporter 3. Toxicol Res (Camb) 2021; 10:91-101. [PMID: 33613977 DOI: 10.1093/toxres/tfaa102] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 11/04/2020] [Accepted: 12/01/2020] [Indexed: 12/14/2022] Open
Abstract
Many individuals infected with human immunodeficiency virus (HIV) are also afflicted with HIV-associated neurocognitive disorders (HANDs). Methamphetamine (METH) abuse puts HIV-1 patients at risk for HANDs because METH and HIV-1 proteins, such as trans-activator of transcription (Tat), can synergistically damage the blood-brain barrier (BBB). However, the underlying mechanism of METH- and HIV-Tat-induced BBB damage remains unclear. In this study, male adult tree shrews and human brain capillary endothelial cells were treated with HIV-Tat, METH, and gastrodin. We used western blotting to examine the expressions of glucose transporters (GLUT1 and GLUT3), tight junctions, and junctional adhesion molecule A (JAMA) and to evaluate the damage and detect Evans blue (EB) and fluorescein sodium in the brain to assess BBB permeability to study the effect of METH and the HIV-1 Tat protein on BBB function in vitro and in vivo. The results showed that the group treated with Tat and METH experienced a significant change at the ultrastructural level of the tree shrew cerebral cortex, decreased protein levels of occluding, claudin-5, Zonula occludens 1 (ZO1), and JAMA in vitro and in vivo, and increased levels of EB and fluorescein sodium in the tree shrew cerebral cortex. The protein levels of GLUT1 and GLUT3 was downregulated in patients with Tat- and METH-induced BBB damage. Pretreatment with gastrodin significantly increased the levels of EB and fluorescein sodium in the tree shrew cerebral cortex and increased the expressions of occluding, ZO1, JAMA, and GLUT1 and GLUT. These results indicate that gastrodin may offer a potential therapeutic option for patients with HANDs.
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Affiliation(s)
- Juan Li
- School of Basic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China.,Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Yunnan Innovation Team of Standardization and Application Research in Tree Shrew, Chinese Academy of Medical Science and Peking Union Medical College, 935 Jiaoling road,Yunnan 650531, China
| | - Jian Huang
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China.,School of Forensic Medicine, Southern Medical University, 1838 Guangzhou Dadao Bei, Baiyun District, Guangzhou 510515, Guangdong, China
| | - Yongwang He
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
| | - Wenguang Wang
- Center of Tree Shrew Germplasm Resources, Institute of Medical Biology, Yunnan Key Laboratory of Vaccine Research and Development on Severe Infectious Diseases, Yunnan Innovation Team of Standardization and Application Research in Tree Shrew, Chinese Academy of Medical Science and Peking Union Medical College, 935 Jiaoling road,Yunnan 650531, China
| | - Chi-Kwan Leung
- School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China.,CUHK-SDU Joint Laboratory of Reproductive Genetics, School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Dongxian Zhang
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
| | - Ruilin Zhang
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
| | - Shangwen Wang
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
| | - Yuanyuan Li
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
| | - Liu Liu
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
| | - Xiaofeng Zeng
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
| | - Zhen Li
- School of Forensic Medicine, Kunming Medical University, 1168 West Chunrong Road, Yuhua Avenue Chenggong, Kunming, Yunnan 650500, China
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Freitas-Andrade M, Raman-Nair J, Lacoste B. Structural and Functional Remodeling of the Brain Vasculature Following Stroke. Front Physiol 2020; 11:948. [PMID: 32848875 PMCID: PMC7433746 DOI: 10.3389/fphys.2020.00948] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 07/14/2020] [Indexed: 12/12/2022] Open
Abstract
Maintenance of cerebral blood vessel integrity and regulation of cerebral blood flow ensure proper brain function. The adult human brain represents only a small portion of the body mass, yet about a quarter of the cardiac output is dedicated to energy consumption by brain cells at rest. Due to a low capacity to store energy, brain health is heavily reliant on a steady supply of oxygen and nutrients from the bloodstream, and is thus particularly vulnerable to stroke. Stroke is a leading cause of disability and mortality worldwide. By transiently or permanently limiting tissue perfusion, stroke alters vascular integrity and function, compromising brain homeostasis and leading to widespread consequences from early-onset motor deficits to long-term cognitive decline. While numerous lines of investigation have been undertaken to develop new pharmacological therapies for stroke, only few advances have been made and most clinical trials have failed. Overall, our understanding of the acute and chronic vascular responses to stroke is insufficient, yet a better comprehension of cerebrovascular remodeling following stroke is an essential prerequisite for developing novel therapeutic options. In this review, we present a comprehensive update on post-stroke cerebrovascular remodeling, an important and growing field in neuroscience, by discussing cellular and molecular mechanisms involved, sex differences, limitations of preclinical research design and future directions.
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Affiliation(s)
| | - Joanna Raman-Nair
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Baptiste Lacoste
- Neuroscience Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
- Brain and Mind Research Institute, University of Ottawa, Ottawa, ON, Canada
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31
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Eiselt É, Otis V, Belleville K, Yang G, Larocque A, Régina A, Demeule M, Sarret P, Gendron L. Use of a Noninvasive Brain-Penetrating Peptide-Drug Conjugate Strategy to Improve the Delivery of Opioid Pain Relief Medications to the Brain. J Pharmacol Exp Ther 2020; 374:52-61. [DOI: 10.1124/jpet.119.263566] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Indexed: 02/04/2023] Open
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Liu L, Li X, Zhang X, Xu T. Biomanufacturing of a novel in vitro biomimetic blood-brain barrier model. Biofabrication 2020; 12:035008. [PMID: 31536969 DOI: 10.1088/1758-5090/ab4647] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A glioma is a malignant tumor that severely threatens human health. However, it is difficult for most therapeutic agents to penetrate through the blood-brain barrier (BBB) and exhibit their antineoplastic activity in the brain. In this article, a biomimetic in vitro BBB model was created by a composite process, this model can provide a significant foundation for the research of drug transport, tumor treatment, tumor microenvironment and other fields. A series of tests and comparative experiments were performed to evaluate this model. The tests showed that the model enabled preliminary simulation of the structure and function of the BBB. Experimental results demonstrated: (1) the new technology enabled controlled release of growth factors and successfully induced endothelial progenitor cells into endothelial cells. Compared with the traditional gold standard, the Transwell model, the expression of four specific proteins that are related to the BBB characteristics was significantly increased (alkaline phosphatase(ALP) by 89.82%, γ-GT by 88.86%, zonula occludens-1 (ZO-1) by 57.40%, and Claudin-5 by 102.32%) in this model; (2) astrocytes had a promoting effect on the microvascular endothelial cells to form tight junction (ZO-1 increased by 249.35%, Claudin-5 increased by 184.99%), and there was a great difference between whether these two types of cells were contact cultured or not; (3) the gelatinous cell U118 had a destructive effect on the tight junction of BBB (ZO-1 decreased by 55.86%, Claudin-5 decreased by 37.84%).
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Affiliation(s)
- Libiao Liu
- Department of Mechanical Engineering, Biomanufacturing Center, Tsinghua University, Beijing 100084, People's Republic of China
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33
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Abrahamson EE, Ikonomovic MD. Brain injury-induced dysfunction of the blood brain barrier as a risk for dementia. Exp Neurol 2020; 328:113257. [PMID: 32092298 DOI: 10.1016/j.expneurol.2020.113257] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 01/31/2020] [Accepted: 02/20/2020] [Indexed: 02/06/2023]
Abstract
The blood-brain barrier (BBB) is a complex and dynamic physiological interface between brain parenchyma and cerebral vasculature. It is composed of closely interacting cells and signaling molecules that regulate movement of solutes, ions, nutrients, macromolecules, and immune cells into the brain and removal of products of normal and abnormal brain cell metabolism. Dysfunction of multiple components of the BBB occurs in aging, inflammatory diseases, traumatic brain injury (TBI, severe or mild repetitive), and in chronic degenerative dementing disorders for which aging, inflammation, and TBI are considered risk factors. BBB permeability changes after TBI result in leakage of serum proteins, influx of immune cells, perivascular inflammation, as well as impairment of efflux transporter systems and accumulation of aggregation-prone molecules involved in hallmark pathologies of neurodegenerative diseases with dementia. In addition, cerebral vascular dysfunction with persistent alterations in cerebral blood flow and neurovascular coupling contribute to brain ischemia, neuronal degeneration, and synaptic dysfunction. While the idea of TBI as a risk factor for dementia is supported by many shared pathological features, it remains a hypothesis that needs further testing in experimental models and in human studies. The current review focusses on pathological mechanisms shared between TBI and neurodegenerative disorders characterized by accumulation of pathological protein aggregates, such as Alzheimer's disease and chronic traumatic encephalopathy. We discuss critical knowledge gaps in the field that need to be explored to clarify the relationship between TBI and risk for dementia and emphasize the need for longitudinal in vivo studies using imaging and biomarkers of BBB dysfunction in people with single or multiple TBI.
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Affiliation(s)
- Eric E Abrahamson
- Geriatric Research Education and Clinical Center, VA Pittsburgh Healthcare System, University of Pittsburgh, Pittsburgh, PA, United States; Department of Neurology, University of Pittsburgh, Pittsburgh, PA, United States
| | - Milos D Ikonomovic
- Geriatric Research Education and Clinical Center, VA Pittsburgh Healthcare System, University of Pittsburgh, Pittsburgh, PA, United States; Department of Neurology, University of Pittsburgh, Pittsburgh, PA, United States; Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA, United States.
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34
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Feng F, Fawcett JP, Zhang H, Tucker IG. Cell-based, animal and H 1 receptor binding studies relative to the sedative effects of ketotifen and norketotifen atropisomers. ACTA ACUST UNITED AC 2020; 72:507-518. [PMID: 32030755 DOI: 10.1111/jphp.13220] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 11/29/2019] [Indexed: 12/01/2022]
Abstract
OBJECTIVES Ketotifen (K) and its active metabolite norketotifen (N) exist as optically active atropisomers. They both have antihistaminic and anti-inflammatory properties but the S-atropisomer of N (SN) causes less sedation than K and RN in rodents. This study investigated whether this could be related to a lower concentration of SN in brain or a lower affinity of SN for rat brain H1 receptors. METHODS Ketotifen and norketotifen atropisomers were quantified using a validated chiral HPLC assay. RBE4 and Caco-2 cell monolayers were used in uptake and permeability studies, respectively. Free and total brain-to-plasma (B/P) ratios were determined after injecting racemic K and N into rat tail veins. Affinity for rat brain H1 receptors (KI ) was determined using the [3 H]mepyramine binding assay. KEY FINDINGS Uptake and permeation studies indicate no stereoselective transport for K or N. B/P ratios reveal the brain concentration of N is lower than K with no stereoselective transport into brain. Finally, the [3 H]mepyramine binding assay shows SN has the lowest affinity for rat brain H1 receptors. CONCLUSION The lower sedative effect of SN in rodents is probably due to a combination of a lower uptake of N than K into the brain and less affinity of SN for CNS H1 receptors.
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Affiliation(s)
- Feifei Feng
- School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - J Paul Fawcett
- School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - Hu Zhang
- School of Pharmacy, University of Otago, Dunedin, New Zealand
| | - Ian G Tucker
- School of Pharmacy, University of Otago, Dunedin, New Zealand
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35
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Mazurek M, Litak J, Kamieniak P, Kulesza B, Jonak K, Baj J, Grochowski C. Metformin as Potential Therapy for High-Grade Glioma. Cancers (Basel) 2020; 12:E210. [PMID: 31952173 PMCID: PMC7016983 DOI: 10.3390/cancers12010210] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 01/09/2020] [Accepted: 01/13/2020] [Indexed: 12/15/2022] Open
Abstract
Metformin (MET), 1,1-dimethylbiguanide hydrochloride, is a biguanide drug used as the first-line medication in the treatment of type 2 diabetes. The recent years have brought many observations showing metformin in its new role. The drug, commonly used in the therapy of diabetes, may also find application in the therapy of a vast variety of tumors. Its effectiveness has been demonstrated in colon, breast, prostate, pancreatic cancer, leukemia, melanoma, lung and endometrial carcinoma, as well as in gliomas. This is especially important in light of the poor options offered to patients in the case of high-grade gliomas, which include glioblastoma (GBM). A thorough understanding of the mechanism of action of metformin can make it possible to discover new drugs that could be used in neoplasm therapy.
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Affiliation(s)
- Marek Mazurek
- Department of Neurosurgery and Pediatric Neurosurgery, Medical University of Lublin, Jaczewskiego 8, 20-954 Lublin, Poland; (M.M.); (J.L.); (P.K.); (B.K.)
| | - Jakub Litak
- Department of Neurosurgery and Pediatric Neurosurgery, Medical University of Lublin, Jaczewskiego 8, 20-954 Lublin, Poland; (M.M.); (J.L.); (P.K.); (B.K.)
- Department of Immunology, Medical University of Lublin, Jaczewskiego 8, 20-954 Lublin, Poland
| | - Piotr Kamieniak
- Department of Neurosurgery and Pediatric Neurosurgery, Medical University of Lublin, Jaczewskiego 8, 20-954 Lublin, Poland; (M.M.); (J.L.); (P.K.); (B.K.)
| | - Bartłomiej Kulesza
- Department of Neurosurgery and Pediatric Neurosurgery, Medical University of Lublin, Jaczewskiego 8, 20-954 Lublin, Poland; (M.M.); (J.L.); (P.K.); (B.K.)
| | - Katarzyna Jonak
- Department of Foregin Languages, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland;
| | - Jacek Baj
- Department of Anatomy, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland;
| | - Cezary Grochowski
- Department of Anatomy, Medical University of Lublin, Jaczewskiego 4, 20-090 Lublin, Poland;
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Seo S, Kim H, Sung JH, Choi N, Lee K, Kim HN. Microphysiological systems for recapitulating physiology and function of blood-brain barrier. Biomaterials 2019; 232:119732. [PMID: 31901694 DOI: 10.1016/j.biomaterials.2019.119732] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 12/20/2019] [Accepted: 12/25/2019] [Indexed: 12/27/2022]
Abstract
Central nervous system (CNS) diseases are emerging as a major issue in an aging society. Although extensive research has focused on the development of CNS drugs, the limited transport of therapeutic agents across the blood-brain barrier (BBB) remains a major challenge. Conventional two-dimensional culture dishes do not recapitulate in vivo physiology and real-time observations of molecular transport are not possible in animal models. Recent advances in engineering techniques have enabled the generation of more physiologically relevant in vitro BBB models, and their applications have expanded from fundamental biological research to practical applications in the pharmaceutical industry. In this article, we provide an overview of recent advances in the development of in vitro BBB models, with a particular focus on the recapitulation of BBB function. The development of biomimetic BBB models is postulated to revolutionize not only fundamental biological studies but also drug screening.
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Affiliation(s)
- Suyeong Seo
- Center for BioMicrosystems, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, 08826, Republic of Korea
| | - Hwieun Kim
- Center for BioMicrosystems, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Department of Chemical Engineering, Hongik University, Seoul, 04066, Republic of Korea
| | - Jong Hwan Sung
- Department of Chemical Engineering, Hongik University, Seoul, 04066, Republic of Korea
| | - Nakwon Choi
- Center for BioMicrosystems, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul, 02792, Republic of Korea; KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea
| | - Kangwon Lee
- Program in Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, 08826, Republic of Korea.
| | - Hong Nam Kim
- Center for BioMicrosystems, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology, Seoul, 02792, Republic of Korea.
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Parker A, Fonseca S, Carding SR. Gut microbes and metabolites as modulators of blood-brain barrier integrity and brain health. Gut Microbes 2019; 11:135-157. [PMID: 31368397 PMCID: PMC7053956 DOI: 10.1080/19490976.2019.1638722] [Citation(s) in RCA: 318] [Impact Index Per Article: 63.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/22/2019] [Accepted: 06/26/2019] [Indexed: 02/03/2023] Open
Abstract
The human gastrointestinal (gut) microbiota comprises diverse and dynamic populations of bacteria, archaea, viruses, fungi, and protozoa, coexisting in a mutualistic relationship with the host. When intestinal homeostasis is perturbed, the function of the gastrointestinal tract and other organ systems, including the brain, can be compromised. The gut microbiota is proposed to contribute to blood-brain barrier disruption and the pathogenesis of neurodegenerative diseases. While progress is being made, a better understanding of interactions between gut microbes and host cells, and the impact these have on signaling from gut to brain is now required. In this review, we summarise current evidence of the impact gut microbes and their metabolites have on blood-brain barrier integrity and brain function, and the communication networks between the gastrointestinal tract and brain, which they may modulate. We also discuss the potential of microbiota modulation strategies as therapeutic tools for promoting and restoring brain health.
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Affiliation(s)
- Aimée Parker
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, UK
| | - Sonia Fonseca
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, UK
| | - Simon R. Carding
- Gut Microbes and Health Research Programme, Quadram Institute Bioscience, Norwich, UK
- Norwich Medical School, University of East Anglia, Norwich, UK
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Borges MH, Pullockaran J, Catalano PM, Baumann MU, Zamudio S, Illsley NP. Human placental GLUT1 glucose transporter expression and the fetal insulin-like growth factor axis in pregnancies complicated by diabetes. Biochim Biophys Acta Mol Basis Dis 2019; 1865:2411-2419. [PMID: 31175930 DOI: 10.1016/j.bbadis.2019.06.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 04/30/2019] [Accepted: 06/03/2019] [Indexed: 12/14/2022]
Abstract
We have previously described regulation of syncytial GLUT1 glucose transporters by IGF-I. Despite this, it is not clear what signal regulates transplacental glucose transport. In this report we asked whether changes in GLUT1 expression and glucose transport activity in diabetic pregnancies were associated with alterations in the fetal IGF axis. Cord blood samples and paired syncytial microvillous and basal membranes were isolated from normal term pregnancies and pregnancies characterized by gestational diabetes type A2 (GDM A2) and pre-existing insulin-dependent diabetes mellitus (IDDM). Circulating IGF-I, basal membrane GLUT1 expression and glucose transporter activity were correlated with birth weight, but only in control, not diabetic groups. Basal membrane GLUT1 and transporter activity were correlated with IGF-I concentrations in control, but not diabetic groups. IGF binding protein (IGFBP) binding capacity showed a ≥50% reduction in the diabetic groups compared to control; both showed a higher level of free IGF-I. The absence of a correlation between birth weight and factors such as fetal IGF-I or GLUT1 expression in the diabetic groups suggests that IGF-I-stimulated effects may have reached a limiting threshold, such that further increases in IGF-I (or GLUT1) are without effect. These data support that fetal IGF-I acts as a fetal nutritional signal, modulating placental GLUT1 expression and birth weight via altered levels of fetal circulating IGFBPs. Diabetes appears to exert its effects on fetal and placental factors prior to the third trimester and, despite good glycemic control immediately prior to, and in the third trimester, these effects persist to term.
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Affiliation(s)
- Marcus H Borges
- Department of Obstetrics, Gynecology and Women's Health, Rutgers-New Jersey Medical School, Newark, NJ, United States of America
| | - Janet Pullockaran
- Department of Obstetrics, Gynecology and Women's Health, Rutgers-New Jersey Medical School, Newark, NJ, United States of America
| | - Patrick M Catalano
- Department of Obstetrics and Gynecology, MetroHealth Medical Center, Cleveland, OH, United States of America
| | - Marc U Baumann
- Department of Obstetrics, Gynecology and Women's Health, Rutgers-New Jersey Medical School, Newark, NJ, United States of America
| | - Stacy Zamudio
- Department of Obstetrics and Gynecology, Hackensack University Medical Center, Hackensack, NJ, United States of America
| | - Nicholas P Illsley
- Department of Obstetrics and Gynecology, Hackensack University Medical Center, Hackensack, NJ, United States of America.
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Moura RP, Martins C, Pinto S, Sousa F, Sarmento B. Blood-brain barrier receptors and transporters: an insight on their function and how to exploit them through nanotechnology. Expert Opin Drug Deliv 2019; 16:271-285. [PMID: 30767695 DOI: 10.1080/17425247.2019.1583205] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
INTRODUCTION The blood-brain barrier (BBB) is a highly limiting barrier that prevents the brain from contacting with several circulating molecules, including harmful agents. However, certain systemic nutrients and macromolecules are able to cross the BBB and reach the brain parenchyma, involving the interaction with multiple receptors and/or transporters at the BBB surface. Nanotechnology allows the creation of drug vehicles, functionalized with targeting ligands for binding specific BBB receptors and/or transporters, hence triggering the transport through this biobarrier. AREAS COVERED This review focuses the BBB receptors/transporters to be exploited in regard to their overall structure and biologic function, as well as their role in the development of strategies envisaging drug delivery to the brain. Then, the interplay between the targeting of these BBB receptors/transporters and nanotechnology is explored, as they can increase by several-fold the effectiveness of brain-targeted therapies. EXPERT OPINION Nanomedicine may be particularly useful in brain drug delivery, mainly due to the possibility of functionalizing nanoparticles to target specific receptors/transporters. Since the BBB is endowed with numerous receptors and transporters responsible for regulating the proper metabolic activity of the brain, their targeting can be a promising bypass strategy to circumvent the hurdle that the BBB represents for brain drug delivery.
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Affiliation(s)
- Rui Pedro Moura
- a CESPU - Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde , Gandra , Portugal
| | - Cláudia Martins
- b I3S - Instituto de Investigação e Inovação em Saúde , Universidade do Porto , Porto , Portugal.,c INEB - Instituto de Engenharia Biomédica , Universidade do Porto , Porto , Portugal.,d ICBAS - Instituto de Ciências Biomédicas Abel Salazar , Universidade do Porto , Porto , Portugal
| | - Soraia Pinto
- b I3S - Instituto de Investigação e Inovação em Saúde , Universidade do Porto , Porto , Portugal.,c INEB - Instituto de Engenharia Biomédica , Universidade do Porto , Porto , Portugal
| | - Flávia Sousa
- a CESPU - Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde , Gandra , Portugal.,b I3S - Instituto de Investigação e Inovação em Saúde , Universidade do Porto , Porto , Portugal.,c INEB - Instituto de Engenharia Biomédica , Universidade do Porto , Porto , Portugal.,d ICBAS - Instituto de Ciências Biomédicas Abel Salazar , Universidade do Porto , Porto , Portugal
| | - Bruno Sarmento
- a CESPU - Instituto de Investigação e Formação Avançada em Ciências e Tecnologias da Saúde , Gandra , Portugal.,b I3S - Instituto de Investigação e Inovação em Saúde , Universidade do Porto , Porto , Portugal.,c INEB - Instituto de Engenharia Biomédica , Universidade do Porto , Porto , Portugal
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Dakic T, Jevdjovic T, Lakic I, Djurasevic SF, Djordjevic J, Vujovic P. Food For Thought: Short-Term Fasting Upregulates Glucose Transporters in Neurons and Endothelial Cells, But Not in Astrocytes. Neurochem Res 2018; 44:388-399. [PMID: 30460639 DOI: 10.1007/s11064-018-2685-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 10/30/2018] [Accepted: 11/15/2018] [Indexed: 12/22/2022]
Abstract
Our group previously reported that 6-h fasting increased both insulin II mRNA expression and insulin level in rat hypothalamus. Given that insulin effects on central glucose metabolism are insufficiently understood, we wanted to examine if the centrally produced insulin affects expression and/or regional distribution of glucose transporters, and glycogen stores in the hypothalamus during short-term fasting. In addition to determining the amount of total and activated insulin receptor, glucose transporters, and glycogen, we also studied distribution of insulin receptors and glucose transporters within the hypothalamus. We found that short-term fasting did not affect the astrocytic 45 kDa GLUT1 isoform, but it significantly increased the amount of endothelial 55 kDa GLUT1, and neuronal GLUT3 in the membrane fractions of hypothalamic proteins. The level of GLUT2 whose presence was detected in neurons, ependymocytes and tanycytes was also elevated. Unlike hepatic glycogen which was decreased, hypothalamic glycogen content was not changed after 6-h fasting. Our findings suggest that neurons may be given a priority over astrocytes in terms of glucose supply even during the initial phase of metabolic response to fasting. Namely, increase in glucose influx into the brain extracellular fluid and neurons by increasing the translocation of GLUT1, and GLUT3 in the cell membrane may represent the first line of defense in times of scarcity. The absence of co-localization of these membrane transporters with the activated insulin receptor suggests this process takes place in an insulin-independent manner.
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Affiliation(s)
- Tamara Dakic
- Department for Comparative Physiology and Ecophysiology, Institute for Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia.
| | - Tanja Jevdjovic
- Department for Comparative Physiology and Ecophysiology, Institute for Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Iva Lakic
- Department for Comparative Physiology and Ecophysiology, Institute for Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Sinisa F Djurasevic
- Department for Comparative Physiology and Ecophysiology, Institute for Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Jelena Djordjevic
- Department for Comparative Physiology and Ecophysiology, Institute for Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
| | - Predrag Vujovic
- Department for Comparative Physiology and Ecophysiology, Institute for Physiology and Biochemistry, Faculty of Biology, University of Belgrade, Belgrade, Serbia
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Ludewig P, Winneberger J, Magnus T. The cerebral endothelial cell as a key regulator of inflammatory processes in sterile inflammation. J Neuroimmunol 2018; 326:38-44. [PMID: 30472304 DOI: 10.1016/j.jneuroim.2018.10.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 09/17/2018] [Accepted: 10/24/2018] [Indexed: 11/18/2022]
Abstract
Cerebral endothelial cells accomplish numerous tasks connected to the maintenance of homeostasis of the central nervous system. They create a barrier between the central nervous system and peripheral blood and regulate mechanotransduction, vascular permeability, rheology, thrombogenesis, and leukocyte adhesion. In pathophysiological conditions (e.g., stroke or ischemia-reperfusion injury) the endothelial functions are impaired, leading to increased vascular permeability, vascular inflammation, leukocyte-endothelium interactions, and transendothelial migration, driving CNS inflammation and neuronal destruction. This review describes the current knowledge on the regulatory roles of endothelial cells in neuroinflammatory processes.
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Affiliation(s)
- Peter Ludewig
- Department of Neurology at the University Medical Center Hamburg- Eppendorf, Hamburg, Germany.
| | - Jack Winneberger
- Department of Neurology at the University Medical Center Hamburg- Eppendorf, Hamburg, Germany
| | - Tim Magnus
- Department of Neurology at the University Medical Center Hamburg- Eppendorf, Hamburg, Germany
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Ziablitsev SV, Pishchulina SV, Kolesnikova SV, Boris RN. Disorders of carbohydrate metabolism in experimental brain injury. ACTA ACUST UNITED AC 2018; 62:18-22. [PMID: 29975470 DOI: 10.15407/fz62.04.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In experimental heavy closed brain injury (mortality infive days - 86%) it is shown that from the first hours the violations of carbohydrate metabolism in the form of triad were formed: the marked hyperglycemia (3.3-3.6 times), hyperinsulinemia (2.4-3.2 times) and insulin resistance (HOMA-indexes increased to 8.0-11.7 times). These changes were caused by a decrease in tissue sensitivity to insulin and were accompanied by decrease in functional activity of the pancreatic β-cells. In total it is possible to consider these changes as a pentad of the typical disorders of carbohydrate metabolism at brain injury.
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Modarres HP, Janmaleki M, Novin M, Saliba J, El-Hajj F, RezayatiCharan M, Seyfoori A, Sadabadi H, Vandal M, Nguyen MD, Hasan A, Sanati-Nezhad A. In vitro models and systems for evaluating the dynamics of drug delivery to the healthy and diseased brain. J Control Release 2018; 273:108-130. [PMID: 29378233 DOI: 10.1016/j.jconrel.2018.01.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 01/22/2018] [Accepted: 01/23/2018] [Indexed: 12/12/2022]
Abstract
The blood-brain barrier (BBB) plays a crucial role in maintaining brain homeostasis and transport of drugs to the brain. The conventional animal and Transwell BBB models along with emerging microfluidic-based BBB-on-chip systems have provided fundamental functionalities of the BBB and facilitated the testing of drug delivery to the brain tissue. However, developing biomimetic and predictive BBB models capable of reasonably mimicking essential characteristics of the BBB functions is still a challenge. In addition, detailed analysis of the dynamics of drug delivery to the healthy or diseased brain requires not only biomimetic BBB tissue models but also new systems capable of monitoring the BBB microenvironment and dynamics of barrier function and delivery mechanisms. This review provides a comprehensive overview of recent advances in microengineering of BBB models with different functional complexity and mimicking capability of healthy and diseased states. It also discusses new technologies that can make the next generation of biomimetic human BBBs containing integrated biosensors for real-time monitoring the tissue microenvironment and barrier function and correlating it with the dynamics of drug delivery. Such integrated system addresses important brain drug delivery questions related to the treatment of brain diseases. We further discuss how the combination of in vitro BBB systems, computational models and nanotechnology supports for characterization of the dynamics of drug delivery to the brain.
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Affiliation(s)
- Hassan Pezeshgi Modarres
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Mohsen Janmaleki
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Mana Novin
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - John Saliba
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Fatima El-Hajj
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon
| | - Mahdi RezayatiCharan
- Breast Cancer Research Center (BCRC), ACECR, Tehran, Iran; School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Amir Seyfoori
- Breast Cancer Research Center (BCRC), ACECR, Tehran, Iran; School of Metallurgy and Materials Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Hamid Sadabadi
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada
| | - Milène Vandal
- Departments of Clinical Neurosciences, Cell Biology and Anatomy, Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Minh Dang Nguyen
- Departments of Clinical Neurosciences, Cell Biology and Anatomy, Biochemistry and Molecular Biology, University of Calgary, Calgary, Canada
| | - Anwarul Hasan
- Biomedical Engineering, Department of Mechanical Engineering, Faculty of Engineering and Architecture, American University of Beirut, Beirut 1107 2020, Lebanon; Department of Mechanical and Industrial Engineering, College of Engineering, Qatar University, Doha, 2713, Qatar
| | - Amir Sanati-Nezhad
- BioMEMS and Bioinspired Microfluidic Laboratory, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Canada; Center for BioEngineering Research and Education, University of Calgary, Calgary, Canada.
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Zhou Y, Peng Z, Seven ES, Leblanc RM. Crossing the blood-brain barrier with nanoparticles. J Control Release 2017; 270:290-303. [PMID: 29269142 DOI: 10.1016/j.jconrel.2017.12.015] [Citation(s) in RCA: 429] [Impact Index Per Article: 61.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/14/2017] [Accepted: 12/17/2017] [Indexed: 01/21/2023]
Abstract
The blood-brain barrier (BBB) is one of the most essential protection mechanisms in the central nervous system (CNS). It selectively allows individual molecules such as small lipid-soluble molecules to pass through the capillary endothelial membrane while limiting the passage of pathogens or toxins. However, this protection mechanism is also a major obstacle during disease state since it dramatically hinders the drug delivery. In recent years, various tactics have been applied to assist drugs to cross the BBB including osmotic disruption of the BBB and chemical modification of prodrugs. Additionally, nanoparticles (NPs)-mediated drug delivery is emerging as an effective and non-invasive system to treat cerebral diseases. In this review, we will summarize and analyze the advances in the drug delivery across the BBB using various NPs in the last decade. The NPs will cover both traditional and novel nanocarriers. The traditional nanocarriers consist of poly(butylcyanoacrylate), poly(lactic-co-glycolic acid), poly(lactic acid) NPs, liposomes and inorganic systems. In the meanwhile, novel nanocarriers such as carbon quantum dots with their recent applications in drug delivery will also be introduced. In terms of significance, this review clearly depicts the BBB structure and comprehensively describes various NPs-mediated drug delivery systems according to different NPs species. Also, the BBB penetration mechanisms are concluded in general, emphasized and investigated in each drug delivery system.
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Affiliation(s)
- Yiqun Zhou
- Department of Chemistry, University of Miami, Coral Gables, FL 33146, USA
| | - Zhili Peng
- Department of Chemistry, University of Miami, Coral Gables, FL 33146, USA; College of Pharmacy and Chemistry, Dali University, Dali, Yunnan 671000, PR China
| | - Elif S Seven
- Department of Chemistry, University of Miami, Coral Gables, FL 33146, USA
| | - Roger M Leblanc
- Department of Chemistry, University of Miami, Coral Gables, FL 33146, USA.
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Kim EH, Lee JH, Oh Y, Koh I, Shim JK, Park J, Choi J, Yun M, Jeon JY, Huh YM, Chang JH, Kim SH, Kim KS, Cheong JH, Kim P, Kang SG. Inhibition of glioblastoma tumorspheres by combined treatment with 2-deoxyglucose and metformin. Neuro Oncol 2017; 19:197-207. [PMID: 27571886 DOI: 10.1093/neuonc/now174] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Background Deprivation of tumor bioenergetics by inhibition of multiple energy pathways has been suggested as an effective therapeutic approach for various human tumors. However, this idea has not been evaluated in glioblastoma (GBM). We hypothesized that dual inhibition of glycolysis and oxidative phosphorylation could effectively suppress GBM tumorspheres (TS). Methods Effects of 2-deoxyglucose (2DG) and metformin, alone and in combination, on GBM-TS were evaluated. Viability, cellular energy metabolism status, stemness, invasive properties, and GBM-TS transcriptomes were examined. In vivo efficacy was tested in a mouse orthotopic xenograft model. Results GBM-TS viability was decreased by the combination of 2DG and metformin. ATP assay and PET showed that cellular energy metabolism was also decreased by this combination. Sphere formation, expression of stemness-related proteins, and invasive capacity of GBM-TS were also significantly suppressed by combined treatment with 2DG and metformin. A transcriptome analysis showed that the expression levels of stemness- and epithelial mesenchymal transition-related genes were also significantly downregulated by combination of 2DG and metformin. Combination treatment also prolonged survival of tumor-bearing mice and decreased invasiveness of GBM-TS. Conclusion The combination of 2DG and metformin effectively decreased the stemness and invasive properties of GBM-TS and showed a potential survival benefit in a mouse orthotopic xenograft model. Our findings suggest that targeting TS-forming cells by this dual inhibition of cellular bioenergetics warrants expedited clinical evaluation for the treatment of GBM.
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Affiliation(s)
- Eui Hyun Kim
- Departments of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Ji-Hyun Lee
- Departments of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Yoonjee Oh
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Ilkyoo Koh
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Jin-Kyoung Shim
- Departments of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Junseong Park
- Departments of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Junjeong Choi
- Departments of Pharmacy, Yonsei University College of Pharmacy, Songdo, Incheon, Republic of Korea
| | - Mijin Yun
- Departments of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jeong Yong Jeon
- Departments of Nuclear Medicine, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Yong Min Huh
- Departments of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jong Hee Chang
- Departments of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sun Ho Kim
- Departments of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Kyung-Sup Kim
- Department of Biochemistry and Molecular Biology, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jae-Ho Cheong
- Department of Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Pilnam Kim
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - Seok-Gu Kang
- Departments of Neurosurgery, Brain Tumor Center, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea
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Endothelial cell-oligodendrocyte interactions in small vessel disease and aging. Clin Sci (Lond) 2017; 131:369-379. [PMID: 28202749 PMCID: PMC5310718 DOI: 10.1042/cs20160618] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Revised: 11/28/2016] [Accepted: 12/14/2016] [Indexed: 12/11/2022]
Abstract
Cerebral small vessel disease (SVD) is a prevalent, neurological disease that significantly increases the risk of stroke and dementia. The main pathological changes are vascular, in the form of lipohyalinosis and arteriosclerosis, and in the white matter (WM), in the form of WM lesions. Despite this, it is unclear to what extent the key cell types involved–the endothelial cells (ECs) of the vasculature and the oligodendrocytes of the WM–interact. Here, we describe the work that has so far been carried out suggesting an interaction between ECs and oligodendrocytes in SVD. As these interactions have been studied in more detail in other disease states and in development, we explore these systems and discuss the role these mechanisms may play in SVD.
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Nguyen HM, Mejia EM, Chang W, Wang Y, Watson E, On N, Miller DW, Hatch GM. Reduction in cardiolipin decreases mitochondrial spare respiratory capacity and increases glucose transport into and across human brain cerebral microvascular endothelial cells. J Neurochem 2016; 139:68-80. [PMID: 27470495 DOI: 10.1111/jnc.13753] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 06/22/2016] [Accepted: 07/15/2016] [Indexed: 02/02/2023]
Abstract
Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. Cardiolipin is a mitochondrial phospholipid required for function of the electron transport chain and ATP generation. We examined the role of cardiolipin in maintaining mitochondrial function necessary to support barrier properties of brain microvessel endothelial cells. Knockdown of the terminal enzyme of cardiolipin synthesis, cardiolipin synthase, in hCMEC/D3 cells resulted in decreased cellular cardiolipin levels compared to controls. The reduction in cardiolipin resulted in decreased mitochondrial spare respiratory capacity, increased pyruvate kinase activity, and increased 2-deoxy-[(3) H]glucose uptake and glucose transporter-1 expression and localization to membranes in hCMEC/D3 cells compared to controls. The mechanism for the increase in glucose uptake was an increase in adenosine-5'-monophosphate kinase and protein kinase B activity and decreased glycogen synthase kinase 3 beta activity. Knockdown of cardiolipin synthase did not affect permeability of fluorescent dextran across confluent hCMEC/D3 monolayers grown on Transwell(®) inserts. In contrast, knockdown of cardiolipin synthase resulted in an increase in 2-deoxy-[(3) H]glucose transport across these monolayers compared to controls. The data indicate that in hCMEC/D3 cells, spare respiratory capacity is dependent on cardiolipin. In addition, reduction in cardiolipin in these cells alters their cellular energy status and this results in increased glucose transport into and across hCMEC/D3 monolayers. Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. In human adult brain endothelial cell hCMEC/D3 monolayers cultured on Transwell(®) plates, knockdown of cardiolipin synthase results in decrease in mitochondrial cardiolipin and decreased mitochondrial spare respiratory capacity. The reduced cardiolipin results in an increased activity of adenosine monophosphate kinase (pAMPK) and protein kinase B (pAKT) and decreased activity of glycogen synthase kinase 3 beta (pGSK3β) which results in elevated glucose transporter-1 (GLUT-1) expression and association with membranes. This in turn increases 2-dexoyglucose uptake from the apical medium into the cells with a resultant 2-deoxyglucose movement into the basolateral medium.
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Affiliation(s)
- Hieu M Nguyen
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
| | - Edgard M Mejia
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
| | - Wenguang Chang
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
| | - Ying Wang
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
| | - Emily Watson
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
| | - Ngoc On
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
| | - Donald W Miller
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada
| | - Grant M Hatch
- Department of Pharmacology and Therapeutics, University of Manitoba, Winnipeg, MB, Canada. .,Biochemistry and Medical Genetics, Center for Research and Treatment of Atherosclerosis, University of Manitoba, DREAM Manitoba Institute of Child Health, Winnipeg, MB, Canada.
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Koutsiaris AG. Wall shear stress in the human eye microcirculation in vivo, segmental heterogeneity and performance of in vitro cerebrovascular models. Clin Hemorheol Microcirc 2016; 63:15-33. [DOI: 10.3233/ch-151976] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Das S, Carnicer-Lombarte A, Fawcett JW, Bora U. Bio-inspired nano tools for neuroscience. Prog Neurobiol 2016; 142:1-22. [PMID: 27107796 DOI: 10.1016/j.pneurobio.2016.04.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 04/14/2016] [Accepted: 04/15/2016] [Indexed: 01/19/2023]
Abstract
Research and treatment in the nervous system is challenged by many physiological barriers posing a major hurdle for neurologists. The CNS is protected by a formidable blood brain barrier (BBB) which limits surgical, therapeutic and diagnostic interventions. The hostile environment created by reactive astrocytes in the CNS along with the limited regeneration capacity of the PNS makes functional recovery after tissue damage difficult and inefficient. Nanomaterials have the unique ability to interface with neural tissue in the nano-scale and are capable of influencing the function of a single neuron. The ability of nanoparticles to transcend the BBB through surface modifications has been exploited in various neuro-imaging techniques and for targeted drug delivery. The tunable topography of nanofibers provides accurate spatio-temporal guidance to regenerating axons. This review is an attempt to comprehend the progress in understanding the obstacles posed by the complex physiology of the nervous system and the innovations in design and fabrication of advanced nanomaterials drawing inspiration from natural phenomenon. We also discuss the development of nanomaterials for use in Neuro-diagnostics, Neuro-therapy and the fabrication of advanced nano-devices for use in opto-electronic and ultrasensitive electrophysiological applications. The energy efficient and parallel computing ability of the human brain has inspired the design of advanced nanotechnology based computational systems. However, extensive use of nanomaterials in neuroscience also raises serious toxicity issues as well as ethical concerns regarding nano implants in the brain. In conclusion we summarize these challenges and provide an insight into the huge potential of nanotechnology platforms in neuroscience.
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Affiliation(s)
- Suradip Das
- Bioengineering Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Alejandro Carnicer-Lombarte
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge CB2 0PY, United Kingdom
| | - James W Fawcett
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Robinson Way, Cambridge CB2 0PY, United Kingdom
| | - Utpal Bora
- Bioengineering Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India; Mugagen Laboratories Private Limited, Technology Incubation Complex, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
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Naftalin RJ. A computer model simulating human glucose absorption and metabolism in health and metabolic disease states. F1000Res 2016; 5:647. [PMID: 27347379 PMCID: PMC4909112 DOI: 10.12688/f1000research.8299.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/31/2016] [Indexed: 12/16/2022] Open
Abstract
A computer model designed to simulate integrated glucose-dependent changes in splanchnic blood flow with small intestinal glucose absorption, hormonal and incretin circulation and hepatic and systemic metabolism in health and metabolic diseases e.g. non-alcoholic fatty liver disease, (NAFLD), non-alcoholic steatohepatitis, (NASH) and type 2 diabetes mellitus, (T2DM) demonstrates how when glucagon-like peptide-1, (GLP-1) is synchronously released into the splanchnic blood during intestinal glucose absorption, it stimulates superior mesenteric arterial (SMA) blood flow and by increasing passive intestinal glucose absorption, harmonizes absorption with its distribution and metabolism. GLP-1 also synergises insulin-dependent net hepatic glucose uptake (NHGU). When GLP-1 secretion is deficient post-prandial SMA blood flow is not increased and as NHGU is also reduced, hyperglycaemia follows. Portal venous glucose concentration is also raised, thereby retarding the passive component of intestinal glucose absorption. Increased pre-hepatic sinusoidal resistance combined with portal hypertension leading to opening of intrahepatic portosystemic collateral vessels are NASH-related mechanical defects that alter the balance between splanchnic and systemic distributions of glucose, hormones and incretins.The model reveals the latent contribution of portosystemic shunting in development of metabolic disease. This diverts splanchnic blood content away from the hepatic sinuses to the systemic circulation, particularly during the glucose absorptive phase of digestion, resulting in inappropriate increases in insulin-dependent systemic glucose metabolism. This hastens onset of hypoglycaemia and thence hyperglucagonaemia. The model reveals that low rates of GLP-1 secretion, frequently associated with T2DM and NASH, may be also be caused by splanchnic hypoglycaemia, rather than to intrinsic loss of incretin secretory capacity. These findings may have therapeutic implications on GLP-1 agonist or glucagon antagonist usage.
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Affiliation(s)
- Richard J Naftalin
- Departments of Physiology and Vascular Biology, BHF centre of research excellence, King's College London School of Medicine, London, UK
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