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Sousa RAL, Yehia A, Abulseoud OA. Attenuation of ferroptosis as a potential therapeutic target for neuropsychiatric manifestations of post-COVID syndrome. Front Neurosci 2023; 17:1237153. [PMID: 37554293 PMCID: PMC10405289 DOI: 10.3389/fnins.2023.1237153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 07/10/2023] [Indexed: 08/10/2023] Open
Abstract
Coronavirus disease-19 (COVID-19), caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), is associated with the persistence of pre-existing or the emergence of new neurological and psychiatric manifestations as a part of a multi-system affection known collectively as "post-COVID syndrome." Cognitive decline is the most prominent feature among these manifestations. The underlying neurobiological mechanisms remain under intense investigation. Ferroptosis is a form of cell death that results from the excessive accumulation of intracellular reactive iron, which mediates lipid peroxidation. The accumulation of lipid-based reactive oxygen species (ROS) and the impairment of glutathione peroxidase 4 (GPX4) activity trigger ferroptosis. The COVID-19-associated cytokine storm enhances the levels of circulating pro-inflammatory cytokines and causes immune-cell hyper-activation that is tightly linked to iron dysregulation. Severe COVID-19 presents with iron overload as one of the main features of its pathogenesis. Iron overload promotes a state of inflammation and immune dysfunction. This is well demonstrated by the strong association between COVID-19 severity and high levels of ferritin, which is a well-known inflammatory and iron overload biomarker. The dysregulation of iron, the high levels of lipid peroxidation biomarkers, and the inactivation of GPX4 in COVID-19 patients make a strong case for ferroptosis as a potential mechanism behind post-COVID neuropsychiatric deficits. Therefore, here we review the characteristics of iron and the attenuation of ferroptosis as a potential therapeutic target for neuropsychiatric post-COVID syndrome.
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Affiliation(s)
- Ricardo A. L. Sousa
- Department of Psychiatry and Psychology, Mayo Clinic Arizona, Phoenix, AZ, United States
| | - Asmaa Yehia
- Department of Psychiatry and Psychology, Mayo Clinic Arizona, Phoenix, AZ, United States
- Department of Medical Physiology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Osama A. Abulseoud
- Department of Psychiatry and Psychology, Mayo Clinic Arizona, Phoenix, AZ, United States
- Department of Neuroscience, Graduate School of Biomedical Sciences, Mayo Clinic College of Medicine, Phoenix, AZ, United States
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Wei Y, Xia X, Li H, Gao H. Influence factors on and potential strategies to amplify receptor-mediated nanodrug delivery across the blood-brain barrier. Expert Opin Drug Deliv 2023; 20:1713-1730. [PMID: 37542516 DOI: 10.1080/17425247.2023.2245332] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 07/22/2023] [Accepted: 08/03/2023] [Indexed: 08/07/2023]
Abstract
INTRODUCTION A major challenge in treating central nervous system (CNS) disorders is to achieve adequate drug delivery across the blood-brain barrier (BBB). Receptor-mediated nanodrug delivery as a Trojan horse strategy has become an exciting approach. However, these nanodrugs do not accumulate significantly in the brain parenchyma, which greatly limits the therapeutic effect of drugs. Amplifying the efficiency of receptor-mediated nanodrug delivery across the BBB becomes the holy grail in the treatment of CNS disorders. AREAS COVERED In this review, we tend to establish links between dynamic BBB and receptor-mediated nanodrug delivery, starting with the delivery processes across the BBB, describing factors affecting nanodrug delivery efficiency, and summarizing potential strategies that may amplify delivery efficiency. EXPERT OPINION Receptor-mediated nanodrug delivery is a common approach to significantly enhance the efficiency of brain-targeting delivery. As BBB is constantly undergoing changes, it is essential to investigate the impact of diseases on the effectiveness of brain-targeting nanodrug delivery. More critically, there are several barriers to achieving brain-targeting nanodrug delivery in the five stages of receptor-mediated transcytosis (RMT), and the impacts can be conflicting, requiring intricate balance. Further studies are also needed to investigate the material toxicity of nanodrugs to address the issue of clinical translation.
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Affiliation(s)
- Ya Wei
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu, P. R. China
| | - Xue Xia
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu, P. R. China
| | - Hanmei Li
- School of Food and Biological Engineering, Chengdu University, Chengdu, P. R. China
| | - Huile Gao
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu, P. R. China
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Unnisa A, Greig NH, Kamal MA. Nanotechnology: A Promising Targeted Drug Delivery System for Brain Tumours and Alzheimer's Disease. Curr Med Chem 2023; 30:255-270. [PMID: 35345990 DOI: 10.2174/0929867329666220328125206] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 01/26/2022] [Accepted: 02/02/2022] [Indexed: 02/08/2023]
Abstract
Nanotechnology is the process of modulating shape and size at the nanoscale to design and manufacture structures, devices, and systems. Nanotechnology's prospective breakthroughs are incredible, and some cannot even be comprehended right now. The blood-brain barrier, which is a prominent physiological barrier in the brain, limits the adequate elimination of malignant cells by changing the concentration of therapeutic agents at the target tissue. Nanotechnology has sparked interest in recent years as a way to solve these issues and improve drug delivery. Inorganic and organic nanomaterials have been found to be beneficial for bioimaging approaches and controlled drug delivery systems. Brain cancer (BC) and Alzheimer's disease (AD) are two of the prominent disorders of the brain. Even though the pathophysiology and pathways for both disorders are different, nanotechnology with common features can deliver drugs over the BBB, advancing the treatment of both disorders. This innovative technology could provide a foundation for combining diagnostics, treatments, and delivery of targeted drugs to the tumour site, further supervising the response and designing and delivering materials by employing atomic and molecular elements. There is currently limited treatment for Alzheimer's disease, and reversing further progression is difficult. Recently, various nanocarriers have been investigated to improve the bioavailability and efficacy of many AD treatment drugs. Nanotechnology-assisted drugs can penetrate the BBB and reach the target tissue. However, further research is required in this field to ensure the safety and efficacy of drug-loaded nanoparticles. The application of nanotechnology in the diagnosis and treatment of brain tumours and Alzheimer's disease is briefly discussed in this review.
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Affiliation(s)
- Aziz Unnisa
- Department of Pharmaceutical Chemistry, College of Pharmacy, University of Hail, Hail, KSA
| | - Nigel H Greig
- Drug Design & Development Section, Translational Gerontology Branch, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 21224, USA
| | - Mohammad A Kamal
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, Sichuan, China.,King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.,Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Dhaka, Bangladesh.,Novel Global Community Educational Foundation, Enzymoics, 7 Peterlee Place, Hebersham, NSW 2770, Australia
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Ishwar D, Haldavnekar R, Das S, Tan B, Venkatakrishnan K. Glioblastoma Associated Natural Killer Cell EVs Generating Tumour-Specific Signatures: Noninvasive GBM Liquid Biopsy with Self-Functionalized Quantum Probes. ACS NANO 2022; 16:10859-10877. [PMID: 35816089 DOI: 10.1021/acsnano.2c03055] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Diagnosis of glioblastoma (GBM) poses a recurring struggle due to many factors, including the presence of the blood-brain barrier (BBB) in addition to the significant tumor heterogeneity. Natural killer (NK) cells of the innate immune system are the primary immune surveillance mechanism for GBM and identify GBM tumors without any previous sensitization. The metabolic reprogramming of NK cells during GBM association is expected to be reflected in its extracellular vesicles. Therefore, tracking the activity of NK cell vesicles in circulation (circulating immune vesicles, CIVs) has great potential for accurate GBM diagnosis. However, identification GBM associated CIVs in circulation is immensely challenging as there is no availability of clinically validated GBM-specific circulating biomarkers. Here, we present GBM associated CIV profiling for noninvasive GBM diagnosis. We investigated the feasibility of using the signals derived from GBM associated CIVs as a de novo methodology for GBM diagnosis. An ultrasensitive sensor and a marker-free approach were essential for the detection of rare signals of GBM associated CIVs. For this purpose, we designed GBM ImmunoProfiler platform using scalable ultrafast laser multiphoton ionization mechanism and adopted surface enhanced Raman spectroscopy (SERS) ensuring simultaneous detection of multiple CIV signals to identify GBM. We experimentally demonstrated that GBM associated CIVs carry unique, tumor-specific signals. The features of GBM associated CIVs were explored through machine learning identifying its similarity with GBM patient blood (without cell isolation) using a very small amount of peripheral blood (5 μL) with 96.82% sensitivity and 100% specificity. In addition, we demonstrated that a tumor associated CIV profile can classify between multiple brain cancer types (astrocytoma, oligodendroglioma, and glioblastoma). We also experimentally demonstrated significant variation in the immune checkpoint protein expression (PDL-1 and CTLA-4) between GBM associated CIVs and uninteracted CIVs. Preclinical analysis with serum specimens of GBM patients showed the possibility of using our technology for minimally invasive GBM diagnosis. With clinical validation, our technology has potential to improve GBM diagnostics with a useful, minimally invasive GBM liquid biopsy.
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Affiliation(s)
- Deeptha Ishwar
- Institute for Biomedical Engineering, Science and Technology (iBEST), Partnership between Toronto Metropolitan University and St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada
- Ultrashort Laser Nanomanufacturing Research Facility, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
- Nano Characterization Laboratory, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
- Nano-Bio Interface Facility, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
| | - Rupa Haldavnekar
- Institute for Biomedical Engineering, Science and Technology (iBEST), Partnership between Toronto Metropolitan University and St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada
- Ultrashort Laser Nanomanufacturing Research Facility, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
- Nano Characterization Laboratory, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
- Nano-Bio Interface Facility, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
| | - Sunit Das
- Department of Surgery, Division of Neurosurgery, University of Toronto, 30 Bond Street, Toronto, M5B1W8, Canada
| | - Bo Tan
- Keenan Research Centre for Biomedical Science, Unity Health Toronto, Toronto, Ontario M5B 1W8, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST), Partnership between Toronto Metropolitan University and St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada
- Nano Characterization Laboratory, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
- Nano-Bio Interface Facility, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
| | - Krishnan Venkatakrishnan
- Keenan Research Centre for Biomedical Science, Unity Health Toronto, Toronto, Ontario M5B 1W8, Canada
- Institute for Biomedical Engineering, Science and Technology (iBEST), Partnership between Toronto Metropolitan University and St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada
- Ultrashort Laser Nanomanufacturing Research Facility, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
- Nano-Bio Interface Facility, Faculty of Engineering and Architectural Sciences, Toronto Metropolitan University, 350 Victoria Street, Toronto, ON M5B 2K3, Canada
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Erickson MA, Banks WA. Transcellular routes of blood-brain barrier disruption. Exp Biol Med (Maywood) 2022; 247:788-796. [PMID: 35243912 DOI: 10.1177/15353702221080745] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Disruption of the blood-brain barrier (BBB) can occur through different mechanisms and pathways. As these pathways result in increased permeability to different classes of substances, it is likely that the neurological insults that occur will also differ for these pathways. The major categories of BBB disruption are paracellular (between cells) and transcellular (across cells) with a subcategory of transcellular leakage involving vesicles (transcytotic). Older literature, as well as more recent studies, highlights the importance of the transcellular pathways in BBB disruption. Of the various transcytotic mechanisms that are thought to be active at the BBB, some are linked to receptor-mediated transcytosis, whereas others are likely involved in BBB disruption. For most capillary beds, transcytotic mechanisms are less clearly linked to permeability than are membrane spanning canaliculi and fenestrations. Disruption pathways share cellular mechanisms to some degree as exemplified by transcytotic caveolar and transcellular canaliculi formations. The discovery of some of the cellular components involved in transcellular mechanisms of BBB disruption and the ability to measure them are adding greatly to our classic knowledge, which is largely based on ultrastructural studies. Future work will likely address the conditions and diseases under which the various pathways of disruption are active, the different impacts that they have, and the cellular biology that underlies the different pathways to disruption.
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Affiliation(s)
- Michelle A Erickson
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA.,Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - William A Banks
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA 98108, USA.,Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
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Li YX, Wang HB, Jin JB, Yang CL, Hu JB, Li J. Advances in the research of nano delivery systems in ischemic stroke. Front Bioeng Biotechnol 2022; 10:984424. [PMID: 36338131 PMCID: PMC9634573 DOI: 10.3389/fbioe.2022.984424] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 10/07/2022] [Indexed: 11/29/2022] Open
Abstract
Ischemic stroke is the most common type of cerebrovascular disease with high disability rate and mortality. The blood-brain barrier (BBB) protects the homeostasis of the brain's microenvironment and impedes the penetration of 98% of drugs. Therefore, effective treatment requires the better drug transport across membranes and increased drug distribution. Nanoparticles are a good choice for drugs to cross BBB. The main pathways of nano delivery systems through BBB include passive diffusion, adsorption-mediated endocytosis, receptor-mediated transport, carrier-mediated transport, etc. At present, the materials used in brain-targeted delivery can be divided into natural polymer, synthetic polymers, inorganic materials and phospholipid. In this review, we first introduced several ways of nano delivery systems crossing the BBB, and then summarized their applications in ischemic stroke. Based on their potential and challenges in the treatment of ischemic stroke, new ideas and prospects are proposed for designing feasible and effective nano delivery systems.
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Affiliation(s)
- Yi-Xuan Li
- Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo, China
| | - Hong-Bo Wang
- Department of Pharmacy, Ningbo University Affiliated Yangming Hospital, Yuyao, China
| | - Jian-Bo Jin
- Department of Pharmacy, Ningbo University Affiliated Yangming Hospital, Yuyao, China
| | - Chun-Lin Yang
- Department of Pharmacy, Ningbo University Affiliated Yangming Hospital, Yuyao, China
| | - Jing-Bo Hu
- Faculty of Materials Science and Chemical Engineering, Ningbo University, Ningbo, China
| | - Jing Li
- Department of Pharmacy, Ningbo University Affiliated Yangming Hospital, Yuyao, China
- *Correspondence: Jing Li,
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7
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Pinheiro RGR, Coutinho AJ, Pinheiro M, Neves AR. Nanoparticles for Targeted Brain Drug Delivery: What Do We Know? Int J Mol Sci 2021; 22:ijms222111654. [PMID: 34769082 PMCID: PMC8584083 DOI: 10.3390/ijms222111654] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 10/18/2021] [Accepted: 10/25/2021] [Indexed: 12/26/2022] Open
Abstract
The blood-brain barrier (BBB) is a barrier that separates the blood from the brain tissue and possesses unique characteristics that make the delivery of drugs to the brain a great challenge. To achieve this purpose, it is necessary to design strategies to allow BBB passage, in order to reach the brain and target the desired anatomic region. The use of nanomedicine has great potential to overcome this problem, since one can modify nanoparticles with strategic molecules that can interact with the BBB and induce uptake through the brain endothelial cells and consequently reach the brain tissue. This review addresses the potential of nanomedicines to treat neurological diseases by using nanoparticles specially developed to cross the BBB.
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Affiliation(s)
- Rúben G. R. Pinheiro
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Ana Joyce Coutinho
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Marina Pinheiro
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
| | - Ana Rute Neves
- LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal
- CQM—Centro de Química da Madeira, Campus da Penteada, Universidade da Madeira, 9020-105 Funchal, Portugal
- Correspondence:
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Erickson MA, Rhea EM, Knopp RC, Banks WA. Interactions of SARS-CoV-2 with the Blood-Brain Barrier. Int J Mol Sci 2021; 22:2681. [PMID: 33800954 PMCID: PMC7961671 DOI: 10.3390/ijms22052681] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 03/03/2021] [Accepted: 03/04/2021] [Indexed: 01/08/2023] Open
Abstract
Emerging data indicate that neurological complications occur as a consequence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The blood-brain barrier (BBB) is a critical interface that regulates entry of circulating molecules into the CNS, and is regulated by signals that arise from the brain and blood compartments. In this review, we discuss mechanisms by which SARS-CoV-2 interactions with the BBB may contribute to neurological dysfunction associated with coronavirus disease of 2019 (COVID-19), which is caused by SARS-CoV-2. We consider aspects of peripheral disease, such as hypoxia and systemic inflammatory response syndrome/cytokine storm, as well as CNS infection and mechanisms of viral entry into the brain. We also discuss the contribution of risk factors for developing severe COVID-19 to BBB dysfunction that could increase viral entry or otherwise damage the brain.
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Affiliation(s)
- Michelle A. Erickson
- Geriatric Research Education and Clinical Center, VA Puget Sound Healthcare System, Seattle, WA 98108, USA; (E.M.R.); (R.C.K.)
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - Elizabeth M. Rhea
- Geriatric Research Education and Clinical Center, VA Puget Sound Healthcare System, Seattle, WA 98108, USA; (E.M.R.); (R.C.K.)
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - Rachel C. Knopp
- Geriatric Research Education and Clinical Center, VA Puget Sound Healthcare System, Seattle, WA 98108, USA; (E.M.R.); (R.C.K.)
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
| | - William A. Banks
- Geriatric Research Education and Clinical Center, VA Puget Sound Healthcare System, Seattle, WA 98108, USA; (E.M.R.); (R.C.K.)
- Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington School of Medicine, Seattle, WA 98104, USA
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Lu L, Chen H, Wang L, Zhao L, Cheng Y, Wang A, Wang F, Zhang X. A Dual Receptor Targeting- and BBB Penetrating- Peptide Functionalized Polyethyleneimine Nanocomplex for Secretory Endostatin Gene Delivery to Malignant Glioma. Int J Nanomedicine 2020; 15:8875-8892. [PMID: 33209022 PMCID: PMC7669533 DOI: 10.2147/ijn.s270208] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/01/2020] [Indexed: 01/09/2023] Open
Abstract
PURPOSE Vascular endothelial growth factor receptor 2 (VEGFR-2) and neuropilin-1 (NRP-1) are two prominent synergistic receptors overexpressed on new blood vessels in glioma and may be promising targets for antiglioma therapy. The aim of this study was to design a dual receptor targeting and blood-brain barrier (BBB) penetrating peptide-modified polyethyleneimine (PEI) nanocomplex that can efficiently deliver the angiogenesis-inhibiting secretory endostatin gene (pVAXI-En) to treat glioma. MATERIALS AND METHODS We first constructed the tandem peptide TAT-AT7 by conjugating AT7 to TAT and evaluated its binding affinity to VEGFR-2 and NRP-1, vasculature-targeting ability and BBB crossing capacity. Then, TAT-AT7-modified PEI polymer (PPTA) was synthesized, and a pVAXI-En-loaded PPTA nanocomplex (PPTA/pVAXI-En) was prepared. The physicochemical properties, cytotoxicity, transfection efficiency, capacities to cross the BBB and BTB (blood-tumor barrier) and glioma-targeting properties of PPTA/pVAXI-En were investigated. Moreover, the in vivo anti-angiogenic behaviors and anti-glioma effects of PPTA/pVAXI-En were evaluated in nude mice. RESULTS The binding affinity of TAT-AT7 to VEGFR-2 and NRP-1 was approximately 3 to 10 times greater than that of AT7 or TAT. The cellular uptake of TAT-AT7 in endothelial cells was 5-fold and 119-fold greater than that of TAT and AT7 alone, respectively. TAT-AT7 also displayed remarkable efficiency in penetrating the BBB and glioma tissue in vivo. PPTA/pVAXI-En exhibited lower cytotoxicity, stronger BBB and BTB traversing abilities, higher selective glioma targeting and better gene transfection efficiency than PEI/pVAXI-En. More importantly, PPTA/pVAXI-En significantly suppressed the tube formation and migration of endothelial cells, inhibited glioma growth, and reduced the microvasculature in orthotopic U87 glioma-bearing nude mice. CONCLUSION Our study demonstrates that PPTA/pVAXI-En can be exploited as an efficient dual-targeting nanocomplex to cross the BBB and BTB, and hence it represents a feasible and promising nonviral gene delivery system for effective glioma therapy.
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Affiliation(s)
- Lu Lu
- Key Laboratory of Chemical Biology (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China
| | - Hongyuan Chen
- Department of General Surgery, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China
| | - Longkun Wang
- Key Laboratory of Chemical Biology (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China
| | - Lin Zhao
- Key Laboratory of Chemical Biology (Ministry of Education), Department of Pharmacology, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China
| | - Yanna Cheng
- Key Laboratory of Chemical Biology (Ministry of Education), Department of Pharmacology, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China
| | - Aijun Wang
- Surgical Bioengineering Laboratory, Department of Surgery, UC Davis Health Medical Center, Sacramento, CA, USA
| | - Fengshan Wang
- Key Laboratory of Chemical Biology (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China
| | - Xinke Zhang
- Key Laboratory of Chemical Biology (Ministry of Education), Department of Pharmacology, School of Pharmaceutical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, People’s Republic of China
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Salameh TS, Rhea EM, Talbot K, Banks WA. Brain uptake pharmacokinetics of incretin receptor agonists showing promise as Alzheimer's and Parkinson's disease therapeutics. Biochem Pharmacol 2020; 180:114187. [PMID: 32755557 PMCID: PMC7606641 DOI: 10.1016/j.bcp.2020.114187] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/29/2020] [Accepted: 07/30/2020] [Indexed: 12/15/2022]
Abstract
Among the more promising treatments proposed for Alzheimer's disease (AD) and Parkinson's disease (PD) are those reducing brain insulin resistance. The antidiabetics in the class of incretin receptor agonists (IRAs) reduce symptoms and brain pathology in animal models of AD and PD, as well as glucose utilization in AD cases and clinical symptoms in PD cases after their systemic administration. At least 9 different IRAs are showing promise as AD and PD therapeutics, but we still lack quantitative data on their relative ability to cross the blood-brain barrier (BBB) reaching the brain parenchyma. We consequently compared brain uptake pharmacokinetics of intravenous 125I-labeled IRAs in adult CD-1 mice over the course of 60 min. We tested single IRAs (exendin-4, liraglutide, lixisenatide, and semaglutide), which bind receptors for one incretin (glucagon-like peptide-1 [GLP-1]), and dual IRAs, which bind receptors for two incretins (GLP-1 and glucose-dependent insulinotropic polypeptide [GIP]), including unbranched, acylated, PEGylated, or C-terminally modified forms (Finan/Ma Peptides 17, 18, and 20 and Hölscher peptides DA3-CH and DA-JC4). The non-acylated and non-PEGylated IRAs (exendin-4, lixisenatide, Peptide 17, DA3-CH and DA-JC4) had significant rates of blood-to-brain influx (Ki), but the acylated IRAs (liraglutide, semaglutide, and Peptide 18) did not measurably cross the BBB. The brain influx of the non-acylated, non-PEGylated IRAs were not saturable up to 1 μg of these drugs and was most likely mediated by adsorptive transcytosis across brain endothelial cells, as observed for exendin-4. Of the non-acylated, non-PEGylated IRAs tested, exendin-4 and DA-JC4 were best able to cross the BBB based on their rate of brain influx, percentage reaching the brain that accumulated in brain parenchyma, and percentage of the systemic dose taken up per gram of brain tissue. Exendin-4 and DA-JC4 thus merit special attention as IRAs well-suited to enter the central nervous system (CNS), thus reaching areas pathologic in AD and PD.
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Affiliation(s)
- Therese S Salameh
- Veterans Affairs Puget Sound Health Care System, Geriatrics Research Education and Clinical Center, Seattle, WA 98108, USA; University of Washington School of Medicine, Division of Gerontology and Geriatric Medicine, Department of Medicine, Seattle, WA 98498, USA
| | - Elizabeth M Rhea
- Veterans Affairs Puget Sound Health Care System, Geriatrics Research Education and Clinical Center, Seattle, WA 98108, USA; University of Washington School of Medicine, Division of Gerontology and Geriatric Medicine, Department of Medicine, Seattle, WA 98498, USA
| | - Konrad Talbot
- Loma Linda University School of Medicine, Departments of Neurosurgery, Basic Sciences, and Pathology and Human Anatomy, Loma Linda, CA 92354, USA
| | - William A Banks
- Veterans Affairs Puget Sound Health Care System, Geriatrics Research Education and Clinical Center, Seattle, WA 98108, USA; University of Washington School of Medicine, Division of Gerontology and Geriatric Medicine, Department of Medicine, Seattle, WA 98498, USA.
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Mansor NI, Nordin N, Mohamed F, Ling KH, Rosli R, Hassan Z. Crossing the Blood-Brain Barrier: A Review on Drug Delivery Strategies for Treatment of the Central Nervous System Diseases. Curr Drug Deliv 2020; 16:698-711. [PMID: 31456519 DOI: 10.2174/1567201816666190828153017] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Revised: 07/24/2019] [Accepted: 07/27/2019] [Indexed: 01/24/2023]
Abstract
Many drugs have been designed to treat diseases of the central nervous system (CNS), especially neurodegenerative diseases. However, the presence of tight junctions at the blood-brain barrier has often compromised the efficiency of drug delivery to target sites in the brain. The principles of drug delivery systems across the blood-brain barrier are dependent on substrate-specific (i.e. protein transport and transcytosis) and non-specific (i.e. transcellular and paracellular) transport pathways, which are crucial factors in attempts to design efficient drug delivery strategies. This review describes how the blood-brain barrier presents the main challenge in delivering drugs to treat brain diseases and discusses the advantages and disadvantages of ongoing neurotherapeutic delivery strategies in overcoming this limitation. In addition, we discuss the application of colloidal carrier systems, particularly nanoparticles, as potential tools for therapy for the CNS diseases.
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Affiliation(s)
- Nur Izzati Mansor
- Medical Genetics Unit, Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Genetics & Regenerative Medicine Research Centre, Faculty of Medicine and Health Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Norshariza Nordin
- Medical Genetics Unit, Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Genetics & Regenerative Medicine Research Centre, Faculty of Medicine and Health Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Farahidah Mohamed
- Department of Pharmaceutical Technology, Faculty of Pharmacy, International Islamic University Malaysia (IIUM), Kuantan, Malaysia.,IKOP Sdn. Bhd., Pilot Plant Pharmaceutical Manufacturing, Faculty of Pharmacy, IIUM, Kuantan, Malaysia.,International Institute of Halal Research & Training (INHART), IIUM, Kuala Lumpur, Malaysia
| | - King Hwa Ling
- Medical Genetics Unit, Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Genetics & Regenerative Medicine Research Centre, Faculty of Medicine and Health Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Rozita Rosli
- Medical Genetics Unit, Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,Genetics & Regenerative Medicine Research Centre, Faculty of Medicine and Health Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia.,UPM-MAKNA Cancer Research Laboratory, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia
| | - Zurina Hassan
- Centre for Drug Research, Universiti Sains Malaysia, Gelugor, Penang, Malaysia
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12
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Chen MB, Yang AC, Yousef H, Lee D, Chen W, Schaum N, Lehallier B, Quake SR, Wyss-Coray T. Brain Endothelial Cells Are Exquisite Sensors of Age-Related Circulatory Cues. Cell Rep 2020; 30:4418-4432.e4. [PMID: 32234477 PMCID: PMC7292569 DOI: 10.1016/j.celrep.2020.03.012] [Citation(s) in RCA: 114] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 11/13/2019] [Accepted: 03/05/2020] [Indexed: 12/28/2022] Open
Abstract
Brain endothelial cells (BECs) are key constituents of the blood-brain barrier (BBB), protecting the brain from pathogens and restricting access of circulatory factors. Yet, because circulatory proteins have prominent age-related effects on adult neurogenesis, neuroinflammation, and cognitive function in mice, we wondered whether BECs receive and potentially relay signals between the blood and brain. Using single-cell RNA sequencing of hippocampal BECs, we discover that capillary BECs-compared with arterial and venous BECs-undergo the greatest transcriptional changes in normal aging, upregulating innate immunity and oxidative stress response pathways. Short-term infusions of aged plasma into young mice recapitulate key aspects of this aging transcriptome, and remarkably, infusions of young plasma into aged mice exert rejuvenation effects on the capillary transcriptome. Together, these findings suggest that the transcriptional age of BECs is exquisitely sensitive to age-related circulatory cues and pinpoint the BBB itself as a promising therapeutic target to treat brain disease.
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Affiliation(s)
- Michelle B Chen
- Department of Bioengineering, Stanford University, Stanford, CA, USA
| | - Andrew C Yang
- Department of Bioengineering, Stanford University, Stanford, CA, USA; Department of Neurology and Neurological Sciences, Stanford School of Medicine, Stanford, CA, USA; ChEM-H, Stanford University, Stanford, CA, USA
| | - Hanadie Yousef
- Department of Neurology and Neurological Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Davis Lee
- Department of Neurology and Neurological Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Winnie Chen
- Department of Neurology and Neurological Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Nicholas Schaum
- Department of Neurology and Neurological Sciences, Stanford School of Medicine, Stanford, CA, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Benoit Lehallier
- Department of Neurology and Neurological Sciences, Stanford School of Medicine, Stanford, CA, USA
| | - Stephen R Quake
- Department of Bioengineering, Stanford University, Stanford, CA, USA; Chan Zuckerberg Biohub, Stanford, CA 94305, USA.
| | - Tony Wyss-Coray
- Department of Neurology and Neurological Sciences, Stanford School of Medicine, Stanford, CA, USA; ChEM-H, Stanford University, Stanford, CA, USA; Department of Veterans Affairs, VA Palo Alto Health Care System, Palo Alto, CA 94304, USA; Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA, USA.
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13
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Hu J, Gao G, He M, Yin Q, Gao X, Xu H, Sun T. Optimal route of gold nanoclusters administration in mice targeting Parkinson’s disease. Nanomedicine (Lond) 2020; 15:563-580. [DOI: 10.2217/nnm-2019-0268] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Aim: To explore the optimal route of gold nanoclusters (AuNCs) administration in mice targeting Parkinson’s disease. Materials & methods: Assessing the pharmacokinetic and bioavailability of AuNCs in mice administrated following intravenous, intraperitoneal, gavage and intranasal injection. Investigating the biodistribution of AuNCs in mice by atomic absorption spectrometry and transmission electron microscope. Toxicity assessments of AuNCs were carried out both in cells and in mice. Results: Administration of AuNCs via intraperitoneal injection showed the greatest bioavailability and the longest residence in brain. AuNCs could penetrate blood–brain barrier and be excreted mainly through kidney. No obvious toxicity of AuNCs found in cells and in mice. Conclusion: The optimal route of AuNCs administration in mice targeting Parkinson’s disease is intraperitoneal administration.
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Affiliation(s)
- Jinqi Hu
- School of Chemistry, Chemical Engineering & Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, PR China
| | - Guanbin Gao
- State Key Laboratory of Advanced Technology for Materials Synthesis & Processing, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, PR China
| | - Meng He
- School of Chemistry, Chemical Engineering & Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, PR China
| | - Qiang Yin
- School of Chemistry, Chemical Engineering & Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, PR China
| | - Xiaobing Gao
- General Hospital of Central Theater Command, No. 627 Wuluo Road, Wuhan, 430070, PR China
| | - Haixing Xu
- School of Chemistry, Chemical Engineering & Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, PR China
| | - Taolei Sun
- School of Chemistry, Chemical Engineering & Life Science, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, PR China
- State Key Laboratory of Advanced Technology for Materials Synthesis & Processing, Wuhan University of Technology, No. 122 Luoshi Road, Wuhan, 430070, PR China
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14
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The application of positron emission tomography (PET) imaging in CNS drug development. Brain Imaging Behav 2019; 13:354-365. [PMID: 30259405 DOI: 10.1007/s11682-018-9967-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
As drug discovery and development in Neuroscience push beyond symptom management to disease modification, neuroimaging becomes a key area of translational research that enables measurements of the presence of drugs and downstream physiological consequences of drug action within the living brain. As such, neuroimaging can be used to help optimize decision-making processes throughout the various phases of drug development. Positron Emission Tomography (PET) is a functional imaging technique that allows the quantification and visualization of biochemical processes, by monitoring the time dependent distribution of molecules labelled with short-lived positron-emitting isotopes. This review focuses on the application of PET to support CNS drug development, particularly in the early clinical phases, by allowing us to measure tissue exposure, target engagement, and pharmacological activity. We will also discuss the application of PET imaging as tools to image the pathological hallmarks of disease and evaluate the potential disease-modifying effect of candidate drugs in slowing disease progression.
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15
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Castillo X, Castro-Obregón S, Gutiérrez-Becker B, Gutiérrez-Ospina G, Karalis N, Khalil AA, Lopez-Noguerola JS, Rodríguez LL, Martínez-Martínez E, Perez-Cruz C, Pérez-Velázquez J, Piña AL, Rubio K, García HPS, Syeda T, Vanoye-Carlo A, Villringer A, Winek K, Zille M. Re-thinking the Etiological Framework of Neurodegeneration. Front Neurosci 2019; 13:728. [PMID: 31396030 PMCID: PMC6667555 DOI: 10.3389/fnins.2019.00728] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023] Open
Abstract
Neurodegenerative diseases are among the leading causes of disability and death worldwide. The disease-related socioeconomic burden is expected to increase with the steadily increasing life expectancy. In spite of decades of clinical and basic research, most strategies designed to manage degenerative brain diseases are palliative. This is not surprising as neurodegeneration progresses "silently" for decades before symptoms are noticed. Importantly, conceptual models with heuristic value used to study neurodegeneration have been constructed retrospectively, based on signs and symptoms already present in affected patients; a circumstance that may confound causes and consequences. Hence, innovative, paradigm-shifting views of the etiology of these diseases are necessary to enable their timely prevention and treatment. Here, we outline four alternative views, not mutually exclusive, on different etiological paths toward neurodegeneration. First, we propose neurodegeneration as being a secondary outcome of a primary cardiovascular cause with vascular pathology disrupting the vital homeostatic interactions between the vasculature and the brain, resulting in cognitive impairment, dementia, and cerebrovascular events such as stroke. Second, we suggest that the persistence of senescent cells in neuronal circuits may favor, together with systemic metabolic diseases, neurodegeneration to occur. Third, we argue that neurodegeneration may start in response to altered body and brain trophic interactions established via the hardwire that connects peripheral targets with central neuronal structures or by means of extracellular vesicle (EV)-mediated communication. Lastly, we elaborate on how lifespan body dysbiosis may be linked to the origin of neurodegeneration. We highlight the existence of bacterial products that modulate the gut-brain axis causing neuroinflammation and neuronal dysfunction. As a concluding section, we end by recommending research avenues to investigate these etiological paths in the future. We think that this requires an integrated, interdisciplinary conceptual research approach based on the investigation of the multimodal aspects of physiology and pathophysiology. It involves utilizing proper conceptual models, experimental animal units, and identifying currently unused opportunities derived from human data. Overall, the proposed etiological paths and experimental recommendations will be important guidelines for future cross-discipline research to overcome the translational roadblock and to develop causative treatments for neurodegenerative diseases.
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Affiliation(s)
- Ximena Castillo
- Instituto de Neurobiología, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Institute of Neurobiology, University of Puerto Rico, San Juan, PR, United States
| | - Susana Castro-Obregón
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Benjamin Gutiérrez-Becker
- Artificial Intelligence in Medical Imaging KJP, Ludwig Maximilian University of Munich, Munich, Germany
| | - Gabriel Gutiérrez-Ospina
- Laboratorio de Biología de Sistemas, Departamento de Biología Celular y Fisiología, Instituto de Investigaciones Biomédicas y Coordinación de Psicobiología y Neurociencias, Facultad de Psicología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Nikolaos Karalis
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | - Ahmed A. Khalil
- Center for Stroke Research Berlin, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | | | - Liliana Lozano Rodríguez
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Eduardo Martínez-Martínez
- Cell Communication & Extracellular Vesicles Laboratory, Instituto Nacional de Medicina Genómica, Mexico City, Mexico
| | - Claudia Perez-Cruz
- National Polytechnic Institute, Center of Research in Advanced Studies, Mexico City, Mexico
| | - Judith Pérez-Velázquez
- Departamento de Matemáticas y Mecánica, Instituto de Investigaciones en Matemáticas Aplicadas y Sistemas, Universidad Nacional Autónoma de México, Mexico City, Mexico
- Mathematische Modellierung Biologischer Systeme, Fakultät für Mathematik, Technische Universität München, Munich, Germany
| | - Ana Luisa Piña
- Department of Neurosurgery, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Karla Rubio
- Lung Cancer Epigenetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | | | - Tauqeerunnisa Syeda
- National Polytechnic Institute, Center of Research in Advanced Studies, Mexico City, Mexico
| | - America Vanoye-Carlo
- Laboratorio de Neurociencias, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Arno Villringer
- Center for Stroke Research Berlin, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Berlin, Germany
- Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany
| | - Katarzyna Winek
- The Shimon Peres Postdoctoral Fellow at the Edmond and Lily Safra Center for Brain Sciences, The Hebrew University of Jerusalem, Jerusalem, Israel
- Department of Experimental Neurology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Marietta Zille
- Institute for Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
- Institute for Medical and Marine Biotechnology, University of Lübeck, Lübeck, Germany
- Fraunhofer Research Institution for Marine Biotechnology and Cell Technology, Lübeck, Germany
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16
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Rhea EM, Banks WA. Role of the Blood-Brain Barrier in Central Nervous System Insulin Resistance. Front Neurosci 2019; 13:521. [PMID: 31213970 PMCID: PMC6558081 DOI: 10.3389/fnins.2019.00521] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 05/06/2019] [Indexed: 01/01/2023] Open
Abstract
The blood-brain barrier (BBB) mediates the communication between the periphery and the central nervous system (CNS). Recently, CNS insulin resistance has been elucidated to play a role in neurodegenerative disease. This has stimulated a wealth of information on the molecular impact of insulin in the brain, particularly in the improvement of cognition. Since the BBB regulates the transport of insulin into the brain and thus, helps to regulate CNS levels, alterations in the BBB response to insulin could impact CNS insulin resistance. In this review, we summarize the effect of insulin on some of the cell types that make up the BBB, including endothelial cells, neurons, astrocytes, and pericytes. We broadly discuss how these changes in specific cell types could ultimately impact the BBB. We also summarize how insulin can regulate levels of the pathological hallmarks of Alzheimer's disease, including amyloid beta (Aβ) and tau within each cell type. Finally, we suggest interventional approaches to overcome detrimental effects on the BBB in regards to changes in insulin transport.
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Affiliation(s)
- Elizabeth M Rhea
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, United States
| | - William A Banks
- Geriatric Research Education and Clinical Center, Veterans Affairs Puget Sound Health Care System, Seattle, WA, United States.,Division of Gerontology and Geriatric Medicine, Department of Medicine, University of Washington, Seattle, WA, United States
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17
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Hladky SB, Barrand MA. Elimination of substances from the brain parenchyma: efflux via perivascular pathways and via the blood-brain barrier. Fluids Barriers CNS 2018; 15:30. [PMID: 30340614 PMCID: PMC6194691 DOI: 10.1186/s12987-018-0113-6] [Citation(s) in RCA: 126] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 08/30/2018] [Indexed: 02/06/2023] Open
Abstract
This review considers efflux of substances from brain parenchyma quantified as values of clearances (CL, stated in µL g-1 min-1). Total clearance of a substance is the sum of clearance values for all available routes including perivascular pathways and the blood-brain barrier. Perivascular efflux contributes to the clearance of all water-soluble substances. Substances leaving via the perivascular routes may enter cerebrospinal fluid (CSF) or lymph. These routes are also involved in entry to the parenchyma from CSF. However, evidence demonstrating net fluid flow inwards along arteries and then outwards along veins (the glymphatic hypothesis) is still lacking. CLperivascular, that via perivascular routes, has been measured by following the fate of exogenously applied labelled tracer amounts of sucrose, inulin or serum albumin, which are not metabolized or eliminated across the blood-brain barrier. With these substances values of total CL ≅ 1 have been measured. Substances that are eliminated at least partly by other routes, i.e. across the blood-brain barrier, have higher total CL values. Substances crossing the blood-brain barrier may do so by passive, non-specific means with CLblood-brain barrier values ranging from < 0.01 for inulin to > 1000 for water and CO2. CLblood-brain barrier values for many small solutes are predictable from their oil/water partition and molecular weight. Transporters specific for glucose, lactate and many polar substrates facilitate efflux across the blood-brain barrier producing CLblood-brain barrier values > 50. The principal route for movement of Na+ and Cl- ions across the blood-brain barrier is probably paracellular through tight junctions between the brain endothelial cells producing CLblood-brain barrier values ~ 1. There are large fluxes of amino acids into and out of the brain across the blood-brain barrier but only small net fluxes have been observed suggesting substantial reuse of essential amino acids and α-ketoacids within the brain. Amyloid-β efflux, which is measurably faster than efflux of inulin, is primarily across the blood-brain barrier. Amyloid-β also leaves the brain parenchyma via perivascular efflux and this may be important as the route by which amyloid-β reaches arterial walls resulting in cerebral amyloid angiopathy.
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Affiliation(s)
- Stephen B. Hladky
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD UK
| | - Margery A. Barrand
- Department of Pharmacology, University of Cambridge, Cambridge, CB2 1PD UK
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18
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Enhancement of drug permeability across blood brain barrier using nanoparticles in meningitis. Inflammopharmacology 2018; 26:675-684. [PMID: 29582240 DOI: 10.1007/s10787-018-0468-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 03/15/2018] [Indexed: 10/17/2022]
Abstract
The central nervous system, one of the most delicate microenvironments of the body, is protected by the blood-brain barrier regulating its homeostasis. Blood-brain barrier is a highly complex structure that tightly regulates the movement of ions of a limited number of small molecules and of an even more restricted number of macromolecules from the blood to the brain, protecting it from injuries and diseases. However, the blood-brain barrier also significantly precludes the delivery of drugs to the brain, thus, preventing the therapy of a number of neurological disorders. As a consequence, several strategies are currently being sought after to enhance the delivery of drugs across the blood-brain barrier. Within this review a brief description of the structural and physiological features of the barriers and the recently born strategy of brain drug delivery based on the use of nanoparticles are described. Finally, the future technological approaches are described. The strong efforts to allow the translation from preclinical to concrete clinical applications are worth the economic investments.
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19
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Paris-Robidas S, Brouard D, Emond V, Parent M, Calon F. Internalization of targeted quantum dots by brain capillary endothelial cells in vivo. J Cereb Blood Flow Metab 2016; 36:731-42. [PMID: 26661181 PMCID: PMC4820005 DOI: 10.1177/0271678x15608201] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 08/27/2015] [Indexed: 12/21/2022]
Abstract
Receptors located on brain capillary endothelial cells forming the blood-brain barrier are the target of most brain drug delivery approaches. Yet, direct subcellular evidence of vectorized transport of nanoformulations into the brain is lacking. To resolve this question, quantum dots were conjugated to monoclonal antibodies (Ri7) targeting the murine transferrin receptor. Specific transferrin receptor-mediated endocytosis of Ri7-quantum dots was first confirmed in N2A and bEnd5 cells. After intravenous injection in mice, Ri7-quantum dots exhibited a fourfold higher volume of distribution in brain tissues, compared to controls. Immunofluorescence analysis showed that Ri7-quantum dots were sequestered throughout the cerebral vasculature 30 min, 1 h, and 4 h post injection, with a decline of signal intensity after 24 h. Transmission electron microscopic studies confirmed that Ri7-quantum dots were massively internalized by brain capillary endothelial cells, averaging 37 ± 4 Ri7-quantum dots/cell 1 h after injection. Most quantum dots within brain capillary endothelial cells were observed in small vesicles (58%), with a smaller proportion detected in tubular structures or in multivesicular bodies. Parenchymal penetration of Ri7-quantum dots was extremely low and comparable to control IgG. Our results show that systemically administered Ri7-quantum dots complexes undergo extensive endocytosis by brain capillary endothelial cells and open the door for novel therapeutic approaches based on brain endothelial cell drug delivery.
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Affiliation(s)
- Sarah Paris-Robidas
- Faculty of Pharmacy, Université Laval, Quebec, Canada Centre de recherche du CHU de Québec, Neurosciences Axis, Quebec, Canada
| | - Danny Brouard
- Research and Development, Héma-Québec, Quebec, Canada
| | - Vincent Emond
- Faculty of Pharmacy, Université Laval, Quebec, Canada Centre de recherche du CHU de Québec, Neurosciences Axis, Quebec, Canada
| | - Martin Parent
- Faculty of Medicine, Université Laval, Quebec, Canada Centre de recherche de l'Institut universitaire en santé mentale de Québec, Quebec, Canada
| | - Frédéric Calon
- Faculty of Pharmacy, Université Laval, Quebec, Canada Centre de recherche du CHU de Québec, Neurosciences Axis, Quebec, Canada
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20
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Targeting of gastrointestinal tract for amended delivery of protein/peptide therapeutics: Strategies and industrial perspectives. J Control Release 2014; 196:168-83. [DOI: 10.1016/j.jconrel.2014.09.031] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 09/26/2014] [Accepted: 09/30/2014] [Indexed: 12/17/2022]
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21
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Park TE, Singh B, Li H, Lee JY, Kang SK, Choi YJ, Cho CS. Enhanced BBB permeability of osmotically active poly(mannitol-co-PEI) modified with rabies virus glycoprotein via selective stimulation of caveolar endocytosis for RNAi therapeutics in Alzheimer's disease. Biomaterials 2014; 38:61-71. [PMID: 25457984 DOI: 10.1016/j.biomaterials.2014.10.068] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/19/2014] [Indexed: 01/02/2023]
Abstract
RNA interference (RNAi) holds one of the promising tools for Alzheimer's disease (AD) treatment by directly arresting the causative genes. For successful RNAi therapeutics for AD, limited access of therapeutic genes to the brain needs to be overcome by developing siRNA delivery system that could cross the blood-brain barrier (BBB). Here, we report a non-viral vector, rabies virus glycoprotein (RVG)-modified poly(mannitol-co-PEI) gene transporter (PMT), R-PEG-PMT. The RVG ligand directed the PMT/siRNA complexes toward the brain through binding to nicotinic acetylcholine receptors expressed on BBB. In mechanistic study using in vitro BBB model, we observed that osmotically-active PMT enhanced the receptor-mediated transcytosis by stimulating the caveolar endocytosis. The potential of RNAi therapeutics for AD using R-PEG-PMT/siBACE1 complexes was demonstrated in vitro and in vivo. Our results suggest that R-PEG-PMT is a powerful gene carrier system for brain targeted RNAi therapeutics with synergistic effect of RVG ligand and PMT on well-modulated receptor-mediated transcytosis through BBB.
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Affiliation(s)
- Tae-Eun Park
- Department of Agricultural Biotechnology & Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, South Korea
| | - Bijay Singh
- Department of Agricultural Biotechnology & Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, South Korea
| | - Huishan Li
- Department of Agricultural Biotechnology & Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, South Korea
| | - Jun-Yeong Lee
- Department of Agricultural Biotechnology & Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, South Korea
| | - Sang-Kee Kang
- Institute of Green-Bio Science & Technology, Seoul National University, Pyeongchanggun, Gangwondo 232-916, South Korea
| | - Yun-Jaie Choi
- Department of Agricultural Biotechnology & Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, South Korea.
| | - Chong-Su Cho
- Department of Agricultural Biotechnology & Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, South Korea.
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22
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Liu D, Lin B, Shao W, Zhu Z, Ji T, Yang C. In vitro and in vivo studies on the transport of PEGylated silica nanoparticles across the blood-brain barrier. ACS APPLIED MATERIALS & INTERFACES 2014; 6:2131-2136. [PMID: 24417514 DOI: 10.1021/am405219u] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Transport of PEGylated silica nanoparticles (PSiNPs) with diameters of 100, 50, and 25 nm across the blood-brain barrier (BBB) was evaluated using an in vitro BBB model based on mouse cerebral endothelial cells (bEnd.3) cultured on transwell inserts within a chamber. In vivo animal experiments were further performed by noninvasive in vivo imaging and ex vivo optical imaging after injection via carotid artery. Confocal fluorescence studies were carried out to evaluate the uptake of PSiNPs by brain endothelial cells. The results showed that PSiNPs can traverse the BBB in vitro and in vivo. The transport efficiency of PSiNPs across BBB was found to be size-dependent, with increased particle size resulting in decreased efficiency. This work points to the potential application of small sized silica nanoparticles in brain imaging or drug delivery.
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Affiliation(s)
- Dan Liu
- Affiliated Chenggong Hospital, State Key Laboratory of Physical Chemistry of Solid Surfaces, the Key Laboratory for Chemical Biology of Fujian Province, The MOE Key Laboratory of Spectrochemical Analysis & Instrumentation, Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, People's Republic of China
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23
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Masserini M. Nanoparticles for brain drug delivery. ISRN BIOCHEMISTRY 2013; 2013:238428. [PMID: 25937958 PMCID: PMC4392984 DOI: 10.1155/2013/238428] [Citation(s) in RCA: 256] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 04/11/2013] [Indexed: 12/24/2022]
Abstract
The central nervous system, one of the most delicate microenvironments of the body, is protected by the blood-brain barrier (BBB) regulating its homeostasis. BBB is a highly complex structure that tightly regulates the movement of ions of a limited number of small molecules and of an even more restricted number of macromolecules from the blood to the brain, protecting it from injuries and diseases. However, the BBB also significantly precludes the delivery of drugs to the brain, thus, preventing the therapy of a number of neurological disorders. As a consequence, several strategies are currently being sought after to enhance the delivery of drugs across the BBB. Within this review, the recently born strategy of brain drug delivery based on the use of nanoparticles, multifunctional drug delivery systems with size in the order of one-billionth of meters, is described. The review also includes a brief description of the structural and physiological features of the barrier and of the most utilized nanoparticles for medical use. Finally, the potential neurotoxicity of nanoparticles is discussed, and future technological approaches are described. The strong efforts to allow the translation from preclinical to concrete clinical applications are worth the economic investments.
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Affiliation(s)
- Massimo Masserini
- Department of Health Sciences, University of Milano-Bicocca, Via Cadore 48, 20900 Monza, Italy
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de Lange EC. The mastermind approach to CNS drug therapy: translational prediction of human brain distribution, target site kinetics, and therapeutic effects. Fluids Barriers CNS 2013; 10:12. [PMID: 23432852 PMCID: PMC3602026 DOI: 10.1186/2045-8118-10-12] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 02/01/2013] [Indexed: 01/11/2023] Open
Abstract
Despite enormous advances in CNS research, CNS disorders remain the world's leading cause of disability. This accounts for more hospitalizations and prolonged care than almost all other diseases combined, and indicates a high unmet need for good CNS drugs and drug therapies.Following dosing, not only the chemical properties of the drug and blood-brain barrier (BBB) transport, but also many other processes will ultimately determine brain target site kinetics and consequently the CNS effects. The rate and extent of all these processes are regulated dynamically, and thus condition dependent. Therefore, heterogenious conditions such as species, gender, genetic background, tissue, age, diet, disease, drug treatment etc., result in considerable inter-individual and intra-individual variation, often encountered in CNS drug therapy.For effective therapy, drugs should access the CNS "at the right place, at the right time, and at the right concentration". To improve CNS therapies and drug development, details of inter-species and inter-condition variations are needed to enable target site pharmacokinetics and associated CNS effects to be translated between species and between disease states. Specifically, such studies need to include information about unbound drug concentrations which drive the effects. To date the only technique that can obtain unbound drug concentrations in brain is microdialysis. This (minimally) invasive technique cannot be readily applied to humans, and we need to rely on translational approaches to predict human brain distribution, target site kinetics, and therapeutic effects of CNS drugs.In this review the term "Mastermind approach" is introduced, for strategic and systematic CNS drug research using advanced preclinical experimental designs and mathematical modeling. In this way, knowledge can be obtained about the contributions and variability of individual processes on the causal path between drug dosing and CNS effect in animals that can be translated to the human situation. On the basis of a few advanced preclinical microdialysis based investigations it will be shown that the "Mastermind approach" has a high potential for the prediction of human CNS drug effects.
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Affiliation(s)
- Elizabeth Cm de Lange
- Division of Pharmacology, Leiden-Academic Center for Drug Research, Leiden University, Leiden, the Netherlands.
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Drug transport into the central nervous system: using newer findings about the blood–brain barriers. Drug Deliv Transl Res 2012; 2:152-9. [DOI: 10.1007/s13346-012-0058-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Redzic Z. Molecular biology of the blood-brain and the blood-cerebrospinal fluid barriers: similarities and differences. Fluids Barriers CNS 2011; 8:3. [PMID: 21349151 PMCID: PMC3045361 DOI: 10.1186/2045-8118-8-3] [Citation(s) in RCA: 247] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Accepted: 01/18/2011] [Indexed: 01/11/2023] Open
Abstract
Efficient processing of information by the central nervous system (CNS) represents an important evolutionary advantage. Thus, homeostatic mechanisms have developed that provide appropriate circumstances for neuronal signaling, including a highly controlled and stable microenvironment. To provide such a milieu for neurons, extracellular fluids of the CNS are separated from the changeable environment of blood at three major interfaces: at the brain capillaries by the blood-brain barrier (BBB), which is localized at the level of the endothelial cells and separates brain interstitial fluid (ISF) from blood; at the epithelial layer of four choroid plexuses, the blood-cerebrospinal fluid (CSF) barrier (BCSFB), which separates CSF from the CP ISF, and at the arachnoid barrier. The two barriers that represent the largest interface between blood and brain extracellular fluids, the BBB and the BCSFB, prevent the free paracellular diffusion of polar molecules by complex morphological features, including tight junctions (TJs) that interconnect the endothelial and epithelial cells, respectively. The first part of this review focuses on the molecular biology of TJs and adherens junctions in the brain capillary endothelial cells and in the CP epithelial cells. However, normal function of the CNS depends on a constant supply of essential molecules, like glucose and amino acids from the blood, exchange of electrolytes between brain extracellular fluids and blood, as well as on efficient removal of metabolic waste products and excess neurotransmitters from the brain ISF. Therefore, a number of specific transport proteins are expressed in brain capillary endothelial cells and CP epithelial cells that provide transport of nutrients and ions into the CNS and removal of waste products and ions from the CSF. The second part of this review concentrates on the molecular biology of various solute carrier (SLC) transport proteins at those two barriers and underlines differences in their expression between the two barriers. Also, many blood-borne molecules and xenobiotics can diffuse into brain ISF and then into neuronal membranes due to their physicochemical properties. Entry of these compounds could be detrimental for neural transmission and signalling. Thus, BBB and BCSFB express transport proteins that actively restrict entry of lipophilic and amphipathic substances from blood and/or remove those molecules from the brain extracellular fluids. The third part of this review concentrates on the molecular biology of ATP-binding cassette (ABC)-transporters and those SLC transporters that are involved in efflux transport of xenobiotics, their expression at the BBB and BCSFB and differences in expression in the two major blood-brain interfaces. In addition, transport and diffusion of ions by the BBB and CP epithelium are involved in the formation of fluid, the ISF and CSF, respectively, so the last part of this review discusses molecular biology of ion transporters/exchangers and ion channels in the brain endothelial and CP epithelial cells.
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Affiliation(s)
- Zoran Redzic
- Department of Physiology, Faculty of Medicine, Kuwait University, SAFAT 13110, Kuwait.
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Abstract
The blood-brain barrier (BBB) regulates passage of nutrients and signaling molecules from the circulation into the brain. Whether lipoproteins cross the BBB in vivo has been controversial, and no clear requirement for circulating lipoproteins in brain development has been shown. We address these issues in Drosophila, which has an functionally conserved BBB, and lipoproteins that resemble those of vertebrates. We show that the Drosophila lipoprotein lipophorin exists in two isoforms. Both isoforms cross the BBB, but accumulate on distinct subsets of cells within the brain. In addition to acting as a lipid carrier, lipophorin carries both sterol-linked and GPI-linked proteins into the circulation and transports them across the BBB. Finally, lipophorin promotes neuroblast proliferation by a mechanism that does not depend on delivery of dietary lipids. Transport of lipophorin and its cargo across the BBB represents a novel mechanism by which peripherally synthesized proteins might enter the brain and influence its development. Furthermore, lipid-linkage may be an efficient method to transport therapeutic molecules across the BBB.
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Chen W, Zhan C, Gu B, Meng Q, Wang H, Lu W, Hou H. Targeted brain delivery of itraconazole via RVG29 anchored nanoparticles. J Drug Target 2010; 19:228-34. [PMID: 20540685 DOI: 10.3109/1061186x.2010.492523] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The blood-brain barrier is a major barrier in the neurological diseases treatment and precludes the entry of drugs from blood to brain. Here, we developed 29-amino-acid peptide derived from rabies virus glycoprotein (RVG29) peptide conjugated itraconazole-loaded albumin nanoparticles (RVG29-ITZ-NPs). The RVG29 peptide was conjugated to the albumin NPs using biotin-binding streptavidin as crosslinker. The NPs were characterized in terms of particle size, zeta potential, drug loading and release behavior in vitro. Cellular uptake of RVG29-ITZ-NPs was investigated by flow cytometry. Pharmacokinetics and brain distribution of RVG29-ITZ-NPs were investigated after intravenous administration of NPs. The particle size of RVG29-ITZ-NPs was 89.3 ± 1.9 nm as determined by dynamic light scattering. The zeta potential of RVG29-ITZ-NPs was -33.1 ± 0.9 mV. RVG29-ITZ-NPs exhibited a sustained release profile within 24 h. In vitro cellular uptake studies demonstrated that RVG29 significantly facilitated the intracellular delivery of NPs. A significant (P < 0.05) accumulation of ITZ in brain was observed for RVG29-ITZ-NPs as compared with ITZ-NPs and cyclodextrin formulation of ITZ (ITZ-CD). These results suggested that RVG29-ITZ-NPs can be exploited as a potential therapeutic formulation for the intracranial fungal infection.
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Affiliation(s)
- Wei Chen
- Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
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Ghabriel MN, Lawrenson JG, Reid AR, Allt G. Endothelial Anionic Surface Charge: The Effect of its Neutralization on the Blood-Nerve Barrier. ACTA ACUST UNITED AC 2009. [DOI: 10.3109/10623329409053381] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Abstract
Substances cross the blood-brain barrier (BBB) by a variety of mechanisms. These include transmembrane diffusion, saturable transporters, adsorptive endocytosis, and the extracellular pathways. Here, we focus on the chief characteristics of two mechanisms especially important in drug delivery: transmembrane diffusion and transporters. Transmembrane diffusion is non-saturable and depends, on first analysis, on the physicochemical characteristics of the substance. However, brain-to-blood efflux systems, enzymatic activity, plasma protein binding, and cerebral blood flow can greatly alter the amount of the substance crossing the BBB. Transport systems increase uptake of ligands by roughly 10-fold and are modified by physiological events and disease states. Most drugs in clinical use to date are small, lipid soluble molecules that cross the BBB by transmembrane diffusion. However, many drug delivery strategies in development target peptides, regulatory proteins, oligonucleotides, glycoproteins, and enzymes for which transporters have been described in recent years. We discuss two examples of drug delivery for newly discovered transporters: that for phosphorothioate oligonucleotides and for enzymes.
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Affiliation(s)
- William A Banks
- Veterans Affairs Medical Center-St Louis, 915 N, Grand Blvd, St, Louis, MO 63106, USA.
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Banks WA. Developing drugs that can cross the blood-brain barrier: applications to Alzheimer's disease. BMC Neurosci 2008; 9 Suppl 3:S2. [PMID: 19090999 PMCID: PMC2604887 DOI: 10.1186/1471-2202-9-s3-s2] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Development of therapeutics for the central nervous system is one of the most challenging areas in drug development. This is primarily because, in addition to all of the other complications one faces in developing new drugs targeting peripheral sites, one must also negotiate the blood-brain barrier (BBB). There are dozens of strategies to overcome the obstacle of the BBB, but many of these are bound to fail, barring extreme serendipity, because they are based on an inaccurate or incomplete picture of the BBB. This article therefore starts with a brief review of the BBB as it pertains to drug development. It then examines some examples of the delivery of drugs to the central nervous system that are relevant to Alzheimer's disease, placing emphasis on peptides, antibodies, and antisense oligonucleotides.
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Affiliation(s)
- William A Banks
- GRECC, Veterans Affairs Medical Center-St. Louis, and Saint Louis University School of Medicine, Division of Geriatrics, Department of Internal Medicine, 915 N. Grand Blvd, St. Louis, MO 63106, USA.
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Smith MW, Gumbleton M. Endocytosis at the blood–brain barrier: From basic understanding to drug delivery strategies. J Drug Target 2008; 14:191-214. [PMID: 16777679 DOI: 10.1080/10611860600650086] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The blood-brain barrier (BBB) protects the central nervous system (CNS) from potentially harmful xenobiotics and endogenous molecules. Anatomically, it comprises the brain microvasculature whose functionality is nevertheless influenced by associated astrocyte, pericyte and neuronal cells. The highly restrictive paracellular pathway within brain microvasculature restricts significant CNS penetration to only those drugs whose physicochemical properties afford ready penetration into hydrophobic cell membranes or are capable of exploiting endogenous active transport processes such as solute carriers or endocytosis pathways. Endocytosis at the BBB is an essential pathway by which the brain obtains its nutrients and affords communication with the periphery. The development of strategies to exploit these endocytic pathways for the purposes of drug delivery to the CNS is still an immature field although some impressive results have been documented with the targeting of particular receptors. This current article initially provides an overview of general endocytosis processes and pathways showing evidence of their functional existence within the BBB. Subsequent sections provide, in an entity-specific manner, comprehensive reviews on BBB transport investigations of endocytosis involving: transferrin and the targeting of the transferrin receptor; hormones; cytokines; cell penetrating peptides; microorganisms and toxins, and nanoparticles aimed at more effectively delivering drugs to the CNS.
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Affiliation(s)
- Mathew W Smith
- Pharmaceutical Cell Biology, Welsh School of Pharmacy, Cardiff University, Redwood Building, Cardiff CF10 3XF, UK
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Mishra V, Mahor S, Rawat A, Gupta PN, Dubey P, Khatri K, Vyas SP. Targeted brain delivery of AZT via transferrin anchored pegylated albumin nanoparticles. J Drug Target 2008; 14:45-53. [PMID: 16603451 DOI: 10.1080/10611860600612953] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Hydrophilic drugs/peptides have poor cross Blood-brain permeability. Various drug delivery systems with diverse surfacial characteristics have been reported for effective translocation of drugs across Blood-brain barrier. In present investigation, the potential of engineered albumin nanoparticles was evaluated for brain specific delivery after intravenous administration. Long circulatory PEGylated albumin nanoparticles encapsulating water-soluble antiviral drug azidothymidine (AZT) were prepared by ultra-emulsification method using chemical cross-linking by glutaraldehyde. Surface of the PEGylated nanoparticles was modified by anchoring transferrin as a ligand for brain targeting. Nanoparticles were characterized for their size, polydispersity, surfacial charge, drug loading and in vitro drug release. Fluorescence studies revealed the enhanced uptake of transferrin-anchored nanoparticles in the brain tissues when compared with unmodified nanoparticles. In vivo evaluation was carried out on albino rats to evaluate tissue distribution of engineered nanoparticles after intravenous administration. A significant ((*)P < 0.01) enhancement of brain localization of AZT was observed for transferrin anchored pegylated albumin nanopariticles (Tf-PEG-NPs). Hence, the specific role of transferrin ligand on nanoparticles for brain targeting was confirmed.
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Affiliation(s)
- Vivek Mishra
- Dr Hari Singh Gour Vishvavidyalaya, Drug Delivery Research Laboratory, Department of Pharmaceutical Sciences, Sagar, (M.P.), 470 002, India
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Hervé F, Ghinea N, Scherrmann JM. CNS delivery via adsorptive transcytosis. AAPS J 2008; 10:455-72. [PMID: 18726697 PMCID: PMC2761699 DOI: 10.1208/s12248-008-9055-2] [Citation(s) in RCA: 363] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2008] [Accepted: 06/30/2008] [Indexed: 11/30/2022] Open
Abstract
Adsorptive-mediated transcytosis (AMT) provides a means for brain delivery of medicines across the blood-brain barrier (BBB). The BBB is readily equipped for the AMT process: it provides both the potential for binding and uptake of cationic molecules to the luminal surface of endothelial cells, and then for exocytosis at the abluminal surface. The transcytotic pathways present at the BBB and its morphological and enzymatic properties provide the means for movement of the molecules through the endothelial cytoplasm. AMT-based drug delivery to the brain was performed using cationic proteins and cell-penetrating peptides (CPPs). Protein cationization using either synthetic or natural polyamines is discussed and some examples of diamine/polyamine modified proteins that cross BBB are described. Two main families of CPPs belonging to the Tat-derived peptides and Syn-B vectors have been extensively used in CPP vector-mediated strategies allowing delivery of a large variety of small molecules as well as proteins across cell membranes in vitro and the BBB in vivo. CPP strategy suffers from several limitations such as toxicity and immunogenicity--like the cationization strategy--as well as the instability of peptide vectors in biological media. The review concludes by stressing the need to improve the understanding of AMT mechanisms at BBB and the effectiveness of cationized proteins and CPP-vectorized proteins as neurotherapeutics.
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Affiliation(s)
- Françoise Hervé
- UFR Biomédicale, Université Paris Descartes, CNRS, UPR2228, 45 rue des Saints-Pères, 75270 Paris, France.
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Norsted E, Gömüç B, Meister B. Protein components of the blood-brain barrier (BBB) in the mediobasal hypothalamus. J Chem Neuroanat 2008; 36:107-21. [PMID: 18602987 DOI: 10.1016/j.jchemneu.2008.06.002] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2008] [Revised: 06/09/2008] [Accepted: 06/09/2008] [Indexed: 01/27/2023]
Abstract
The blood-brain barrier (BBB) plays an important role in controlling the access of substances to the brain. Of the circumventricular organs (CVO), i.e. areas that lack a BBB, the median eminence and its close relationship with the hypothalamic arcuate nucleus plays an important role in controlling the entry of blood-borne substances to neurons of the mediobasal hypothalamus. In order to clarify the nature of the BBB in the median eminence-arcuate nucleus complex, we have used immunohistochemistry and antisera to protein components of the BBB-(1) tight junctions, claudin-5 and zona occludens-1 (ZO-1); (2) endothelial cells: (a) all endothelial cells: rat endothelial cell antigen-1 (RECA-1), (b) endothelial cells at BBB: endothelial barrier antigen (EBA), glucose transporter 1 (GLUT1) and transferrin receptor (TfR), and (c) endothelial cells at CVOs: dysferlin; (3) basal lamina: laminin; (4) vascular smooth muscle cells: smooth muscle actin (SMA); (5) pericytes: chondroitin sulfate proteoglycan (NG2); (6) glial cells: (a) astrocytes: glial fibrillary acidic protein (GFAP), (b) tanycytes: dopamine- and cAMP-regulated phosphoprotein of 32kDA (DARPP-32), (c) microglia: CD11b. Neuronal cell bodies located in the ventromedial aspect of the arcuate nucleus were visualized by antiserum to agouti-related protein (AgRP). The study provides a detailed analysis on the cellular localization of BBB components in the mediobasal hypothalamus. Some vessels in the ventromedial aspect of the arcuate nucleus lacked the BBB markers EBA and TfR, suggesting an absence of an intact BBB. These vessels may represent a route of entry for circulating substances to a subpopulation of arcuate nucleus neurons.
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Affiliation(s)
- Ebba Norsted
- Department of Neuroscience, The Retzius Laboratory, Karolinska Institutet, Retzius väg 8, SE-171 77 Stockholm, Sweden
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36
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Banks WA. Delivery of peptides to the brain: Emphasis on therapeutic development. Biopolymers 2008; 90:589-94. [DOI: 10.1002/bip.20980] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Smith M, Omidi Y, Gumbleton M. Primary porcine brain microvascular endothelial cells: biochemical and functional characterisation as a model for drug transport and targeting. J Drug Target 2007; 15:253-68. [PMID: 17487694 DOI: 10.1080/10611860701288539] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The blood-brain barrier (BBB) remains a significant obstacle to the delivery of therapeutic agents into the central nervous system (CNS). Primary cell cultures of brain capillary endothelial cells represent the closest possible phenotype to the in vivo BBB cell providing a convenient model for the study of transport systems and events that mediate solute delivery to the CNS. In this investigation we have characterized an in vitro primary BBB model from porcine brain microvascular endothelial capillary (PBMVEC) cells after recovery from cryopreservation of upto 12 months and studied their modulation by astrocytes. Co-cultures of PBMVECs with astrocytes (C6 astroglioma) resulted in trans-endothelial electrical resistance of up to approximately 900Omega cm2 and marked discrimination between the para- and trans- cellular markers sucrose and propranolol. Micrographs of confluent monolayers of PBMVECs showed the presence of tight junction complexes and vesicles with the morphological characteristics of either caveolae or clathrin coated pits. Extensive RT-PCR evaluation highlighted the expression of tight junction transcripts, ABC transporters, leptin receptor and select nutrient transporters. Functional studies examined the kinetics of transport of glucose, large neutral amino acids and p-glycoprotein (P-gp). Our findings indicate primary PBMVECs retain many barrier characteristics and transport pathways of the in vivo BBB. Further, primary cells can be stored as frozen stocks which can be thawed and cultured without phenotypic drift many months after isolation. Frozen PBMVECs therefore serve as a robust and convenient in vitro cell culture tool for research programs involving CNS drug delivery and targeting and in studies addressing blood-brain barrier transport mechanisms.
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Affiliation(s)
- Mathew Smith
- Pharmaceutical Cell Biology, Welsh School of Pharmacy, Cardiff University, Cardiff, UK
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39
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Abstract
The specialized cerebral microvascular endothelium interacts with the cellular milieu of the brain and extracellular matrix to form a neurovascular unit, one aspect of which is a regulated interface between the blood and central nervous system (CNS). The concept of this blood-brain barrier (BBB) as a dynamically regulated system rather than a static barrier has wide-ranging implications for pathophysiology of the CNS. While in vitro models of the BBB are useful for screening drugs targeted to the CNS and indispensable for studies of cerebral endothelial cell biology, the complex interactions of the neurovascular unit make animal-based models and methods essential tools for understanding the pathophysiology of the BBB. BBB dysfunction is a complication of neurodegenerative disease and brain injury. Studies on animal models have shown that diseases of the periphery, such as diabetes and inflammatory pain, have deleterious effects on the BBB which may contribute to neurological complications associated with these conditions. Furthermore, genetic and/or epigenetic abnormalities in constituents of the BBB may be significant contributing factors in disease etiology. Research that approaches the BBB as a dynamic system integrated with both the CNS and the periphery is therefore critical to understanding and treating diseases of the CNS. Herein, we review various methodological approaches used to study BBB function in the context of disease. These include measurement of transport between blood and brain, imaging-based technologies, and genomic/proteomic approaches.
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Cheunsuang O, Stewart AL, Morris R. Differential uptake of molecules from the circulation and CSF reveals regional and cellular specialisation in CNS detection of homeostatic signals. Cell Tissue Res 2006; 325:397-402. [PMID: 16555054 DOI: 10.1007/s00441-006-0162-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2005] [Accepted: 12/20/2005] [Indexed: 12/12/2022]
Abstract
The uptake of hydroxystilbamidine (OHSt, FluoroGold equivalent) and wheat germ agglutinin (WGA), into the hypothalamus, two hours after injections into either the circulation or the cerebrospinal fluid, were compared in adult rats. Following intravenous injection, OHSt was found in astrocytes of the median eminence and medial part of the arcuate nucleus whereas WGA intensely labelled the blood vessels and ependymal cells throughout the hypothalamus. In complete contrast, intracerebroventricular (icv) injection into the lateral ventricle resulted in OHSt uptake by ependymocytes and astrocytes in the area adjacent to the third ventricle, with virtually no uptake in regions taking up this dye following systematic injections, i.e., the median eminence and medial arcuate. Following icv injection WGA labelling was intense in all parts of the ependymal layer of the third ventricle, including the alpha- and beta-tanycytes. Injections into the cisterna magna gave a different pattern of uptake with OHSt being found only in astrocytes in the ventral part of the hypothalamus lateral to the arcuate nucleus whilst WGA uptake was virtually absent. This highlights the regional and cellular specialisation for uptake of molecules from the circulation and CSF. The median eminence and medial arcuate take up molecules from the circulation, with different cell types taking up different molecules. As the CSF flows through the ventricular system, different cells lining the ventricular and subarachnoid spaces take up molecules differentially. Molecules in the CSF appear to be excluded from the median eminence and medial arcuate region.
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Affiliation(s)
- Ornsiri Cheunsuang
- Department of Veterinary Anatomy, Chulalongkorn University, Bangkok, Thailand
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41
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The Endothelium. Vasc Med 2006. [DOI: 10.1016/b978-0-7216-0284-4.50007-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Visser CC, Stevanović S, Voorwinden LH, van Bloois L, Gaillard PJ, Danhof M, Crommelin DJA, de Boer AG. Targeting liposomes with protein drugs to the blood–brain barrier in vitro. Eur J Pharm Sci 2005; 25:299-305. [PMID: 15911226 DOI: 10.1016/j.ejps.2005.03.008] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2004] [Revised: 03/01/2005] [Accepted: 03/08/2005] [Indexed: 11/22/2022]
Abstract
In this study, we aim to target pegylated liposomes loaded with horseradish peroxidase (HRP) and tagged with transferrin (Tf) to the BBB in vitro. Liposomes were prepared with the post-insertion technique: micelles of polyethylene glycol (PEG) and PEG-Tf were inserted into pre-formed liposomes containing HRP. Tf was measured indirectly by measuring iron via atomic absorption spectroscopy. All liposomes were around 100 nm in diameter, contained 5-13 microg HRP per mumol phospholipid and 63-74 Tf molecules per liposome (lipo Tf) or no Tf (lipo C). Brain capillary endothelial cells (BCEC) were incubated with liposomes at 4 degrees C (to determine binding) or at 37 degrees C (to determine association, i.e. binding+endocytosis) and the HRP activity, rather than the HRP amount was determined in cell lysates. Association of lipo Tf was two- to three-fold higher than association of lipo C. Surprisingly, the binding of lipo Tf at 4 degrees C was four-fold higher than the association of at 37 degrees C. Most likely this high binding and low endocytosis is explained by intracellular degradation of endocytosed HRP. In conclusion, we have shown targeting of liposomes loaded with protein or peptide drugs to the BCEC and more specifically to the lysosomes. This is an advantage for the treatment of lysosomal storage disease. However, drug targeting to other intracellular targets also results in intracellular degradation of the drug. Our experiments suggest that liposomes release some of their content within the BBB, making targeting of liposomes to the TfR on BCEC an attractive approach for brain drug delivery.
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Affiliation(s)
- Corine C Visser
- Leiden/Amsterdam Centre for Drug Research (LACDR), Leiden University, Division of Pharmacology, PO Box 9502, 2300 RA Leiden, The Netherlands
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Ueno M, Akiguchi I, Yagi H, Naiki H, Fujibayashi Y, Kimura J, Takeda T. Age-related changes in barrier function in mouse brain I. Accelerated age-related increase of brain transfer of serum albumin in accelerated senescence prone SAM-P/8 mice with deficits in learning and memory. Arch Gerontol Geriatr 2005; 16:233-48. [PMID: 15374337 DOI: 10.1016/0167-4943(93)90035-g] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/1992] [Revised: 04/16/1993] [Accepted: 04/22/1993] [Indexed: 10/27/2022]
Abstract
The time course of brain accumulation of radiolabelled human serum albumin ((125)I-HSA) injected intravenously and the transfer of (125)I-HSA from blood to brain were evaluated in DDD mice using a double isotope technique. The brain accumulation of (125)I-HSA at 3 and 9 h but not at 24 h postinjection and the brain transfer rates were significantly higher in 22-month-old DDD mice than in 4-month-old ones. The brain transfer rates of (125)I-HSA were measured also in senescence accelerated prone mice (SAM-P/8) with age-related deficits in learning and memory, and in senescence accelerated resistant mice (SAM-R/I) without these deficits. The brain transfer rates were significantly higher in 13-month-old SAM-P/8 and 22-month-old SAM-R/1 than in 3-month-old mice of the same strains, respectively. The mean brain transfer rates in five regions observed in 22-month-old DDD mice, 22-month-old SAM-R/1 and 13-month-old SAM-P/8 increased by 31%, 41% and 51% compared with corresponding values in 3- or 4-month-old mice of the same strains. DDD mice and SAM-R/1 mice with normal characteristics of aging showed similar age-related significant changes in brain transfer rates. Age-related increase in the brain transfer rate was manifested at the youngest age in SAM-P/8 among the three strains examined. These findings show that the transfer of human serum albumin into the mouse brain increases with aging and suggest that the barrier function in the mouse brain against macromolecules changes with aging.
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Affiliation(s)
- M Ueno
- Department of Senescence Biology, Chest Disease Research Institute, Kyoto University, Japan
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44
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Bendayan R, Lee G, Bendayan M. Functional expression and localization of P-glycoprotein at the blood brain barrier. Microsc Res Tech 2002; 57:365-80. [PMID: 12112443 DOI: 10.1002/jemt.10090] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Until recently, the blood-brain barrier was viewed as a static lipid membrane barrier. Physical attributes of the cerebral endothelial cells such as the presence of tight junctions, paucity of vesicles or caveolae, and high electrical resistance were believed to be the primary components that provide the membrane selectivity of the blood-brain barrier to a variety of circulating compounds from the periphery. However, results from molecular biology, immunocytochemistry, biochemistry, and transport studies show that the cerebral endothelial cells possess an asymmetrical array of metabolic enzymes (i.e., alkaline phosphatase, cytochrome P450 enzymes, glutathione transferases) and energy-dependent efflux transport proteins (i.e., P-glycoprotein and Multidrug-resistance proteins) that are instrumental to the barrier function. P-glycoprotein, a membrane-associated, energy-dependent, efflux transporter, is expressed in brain parenchyma (i.e., astrocytes and microglia) as well as in blood-brain and blood-cerebrospinal fluid barriers. Its function along the blood-brain barrier is believed to prevent the accumulation of potentially harmful compounds in the brain by actively removing them from the brain into the peripheral circulation. This is a brief review on the expression and activity of P-glycoprotein at the blood-brain barrier, which reports on the localization of the protein in rat brain capillaries in situ as well as in a well-characterized in vitro model of the blood-brain barrier, an immortalized rat brain endothelial cell line, the RBE4. Immunocytochemical analysis employing various P-glycoprotein monoclonal antibodies, demonstrated the presence of the protein along the plasma membrane, in plasmalemmal vesicles and nuclear envelope of rat cerebral endothelial cells, both in situ and in vitro. Western blot analysis revealed a single band with a molecular weight of 170-180 kDa, a size previously reported for P-glycoprotein, in RBE4 cells. In addition, results from functional studies show that the accumulation of the P-glycoprotein substrate digoxin by RBE4 monolayer cells is significantly enhanced in the presence of standard P-glycoprotein inhibitors (verapamil, cyclosporin A, PSC 833), protease inhibitors (saquinavir, ritonavir, indinavir), and the metabolic inhibitor, sodium azide. These results demonstrate the functional expression of P-glycoprotein in the immortalized rat brain endothelial cell line, RBE4. Novel in situ and in vitro intracellular locations of P-glycoprotein in cerebral endothelial cells have been identified suggesting that this transporter may play a significant role in the subcellular distribution of substrates in the brain.
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Affiliation(s)
- Reina Bendayan
- Department of Pharmaceutical Sciences, Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada.
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Grasso G, Buemi M, Alafaci C, Sfacteria A, Passalacqua M, Sturiale A, Calapai G, De Vico G, Piedimonte G, Salpietro FM, Tomasello F. Beneficial effects of systemic administration of recombinant human erythropoietin in rabbits subjected to subarachnoid hemorrhage. Proc Natl Acad Sci U S A 2002; 99:5627-31. [PMID: 11943864 PMCID: PMC122821 DOI: 10.1073/pnas.082097299] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2001] [Accepted: 02/19/2002] [Indexed: 12/27/2022] Open
Abstract
Cerebral vasospasm and ischemic damage are important causes of mortality and morbidity in patients affected by aneurysmal subarachnoid hemorrhage (SAH). Recently, i.p. administration of recombinant human erythropoietin (r-Hu-EPO) has been shown to exert a neuroprotective effect during experimental SAH. The present study was conducted to evaluate further the effect of r-Hu-EPO administration after SAH in rabbits on neurological outcome, degree of basilar artery spasm, and magnitude of neuronal ischemic damage. Experimental animals were divided into six groups: group 1 (n = 8), control; group 2 (n = 8), control plus placebo; group 3 (n = 8), control plus r-Hu-EPO; group 4 (n = 8), SAH; group 5 (n = 8), SAH plus placebo; group 6 (n = 8), SAH plus r-Hu-EPO. r-Hu-EPO, at a dose of 1,000 units/kg, and placebo were injected i.p. starting 5 min after inducing SAH and followed by clinical and pathological assessment 72 h later. Systemic administration of r-Hu-EPO produced significant increases in cerebrospinal fluid EPO concentrations (P < 0.001), and reduced vasoconstriction of the basilar artery (P < 0.05), ischemic neuronal damage (P < 0.001), and subsequent neurological deterioration (P < 0.05). These observations suggest that r-Hu-EPO may provide an effective treatment to reduce the post-SAH morbidity.
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Affiliation(s)
- Giovanni Grasso
- Department of Neurosurgery, University of Messina, 98122 Messina, Italy.
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46
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Thorne RG, Frey WH. Delivery of neurotrophic factors to the central nervous system: pharmacokinetic considerations. Clin Pharmacokinet 2002; 40:907-46. [PMID: 11735609 DOI: 10.2165/00003088-200140120-00003] [Citation(s) in RCA: 364] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Neurotrophic factors are proteins with considerable potential in the treatment of central nervous system (CNS) diseases and traumatic injuries. However, a significant challenge to their clinical use is the difficulty associated with delivering these proteins to the CNS. Neurotrophic factors are hydrophilic, typically basic, monomeric or dimeric proteins, mostly in the size range of 5 to 30 kDa. Neurotrophic factors potently support the development, growth and survival of neurons, eliciting biological effects at concentrations in the nanomolar to femtomolar range. They are not orally bioavailable and the blood-brain and blood-cerebrospinal fluid barriers severely limit their ability to enter into and act on sites in the CNS following parenteral systemic routes of administration. Most neurotrophic factors have short in vivo half-lives and poor pharmacokinetic profiles. Their access to the CNS is restricted by rapid enzymatic inactivation, multiple clearance processes, potential immunogenicity and sequestration by binding proteins and other components of the blood and peripheral tissues. The development of targeted drug delivery strategies for neurotrophic factors will probably determine their clinical effectiveness for CNS conditions. Achieving significant CNS target site concentrations while limiting systemic exposure and distribution to peripheral sites of action will lessen unwanted pleiotropic effects and toxicity. Local introduction of neurotrophic factors into the CNS intraparenchymally by direct injection/infusion or by implantation of delivery vectors such as polymer matrices or genetically modified cells yields the highest degree of targeting, but is limited by diffusion restrictions and invasiveness. Delivery of neurotrophic factors into the cerebrospinal fluid (CSF) following intracerebroventricular or intrathecal administration is less invasive and allows access to a much wider area of the CNS through CSF circulation pathways. However, diffusional and cellular barriers to penetration into surrounding CNS tissue and significant clearance of CSF into the venous and lymphatic circulation are also limiting. Unconventional delivery strategies such as intranasal administration may offer some degree of CNS targeting with minimal invasiveness. This review presents a summary of the neurotrophic factors and their indications for CNS disorders, their physicochemical characteristics and the different approaches that have been attempted or suggested for their delivery to the CNS. Future directions for further research such as the potential for CNS disease treatment utilising combinations of neurotrophic factors, displacement strategies, small molecule mimetics, chimaeric molecules and gene therapy are also discussed.
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Affiliation(s)
- R G Thorne
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota, USA
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Ueno M, Tomimoto H, Akiguchi I, Wakita H, Sakamoto H. Blood-brain barrier disruption in white matter lesions in a rat model of chronic cerebral hypoperfusion. J Cereb Blood Flow Metab 2002; 22:97-104. [PMID: 11807399 DOI: 10.1097/00004647-200201000-00012] [Citation(s) in RCA: 114] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Blood-brain barrier damage has been implicated in the pathogenesis of cerebrovascular white matter lesions. This type of lesion is responsible for cognitive impairment in the elderly and can be induced by permanent ligation of the bilateral common carotid arteries in the rat. Because it is unclear whether the blood-brain barrier is impaired, we examined whether vascular permeability to horseradish peroxidase is altered using this model. According to light microscopic results, the reaction product of horseradish peroxidase was most intensely localized to the paramedian part of the corpus callosum in the brain, occurring to a small degree at 3 hours, day 1, markedly on day 3, but reduced on days 7 and 14. By electron microscopic study of the same area, the reaction product of horseradish peroxidase was localized to the plasmalemmal vesicles in the endothelial cells 3 hours after ligation, but appeared in the cytoplasm on days 1 and 3, suggesting a diffuse leakage of horseradish peroxidase. In addition, the reaction product was dispersed into the cytoplasm of glial cells in the perivascular regions on day 3. The luminal surface of the endothelial cell cytoplasm appeared irregular on day 7, suggesting a conformational change of the endothelial cells. Collagen fibrils proliferated in the thickened basal lamina and mitochondria degenerated in the pericyte on days 7 and 14. Perivascular glial endfeet were swollen throughout the survival period. In sham-operated rats, the reaction product of horseradish peroxidase was not observed at any time interval, except in vesicular structures. These findings indicate that chronic cerebral hypoperfusion induces blood-brain barrier damage with subsequent morphologic changes of the vascular structures in the corpus callosum. An extravasation of macromolecules, such as proteases and immunoglobulins, may contribute to the pathogenesis of white matter lesions.
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Affiliation(s)
- Masaki Ueno
- Second Department of Pathology, Kagawa Medical University, Kita-gun, Kagawa, Japan
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Librizzi L, Janigro D, De Biasi S, de Curtis M. Blood-brain barrier preservation in the in vitro isolated guinea pig brain preparation. J Neurosci Res 2001; 66:289-97. [PMID: 11592126 DOI: 10.1002/jnr.1223] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The morphofunctional preservation of the blood-brain barrier (BBB) was evaluated in the isolated guinea pig brain maintained in vitro by arterial perfusion. Electron microscopy evaluation after 5 hr in vitro demonstrated that cerebral capillaries and BBB specializations in this preparation retain features compatible with structural integrity. BBB-impermeable and -permeable atropine derivatives arterially perfused to antagonize carbachol-induced fast oscillatory activity confirmed the functional preservation of the BBB in vitro. To study BBB function further, changes in extracellular K+ concentration during arterial perfusion of a high-K+ solution were measured with K+-sensitive electrodes positioned in the cortex and, as control, at the brain venous outlet, where the solution perfused through the brain arterial system was collected. After 5 hr in vitro, the [K+](o) values measured during high-K+ perfusion in the piriform and entorhinal cortices were 5.02 +/- 0.17 mM (mean +/- SE) and 5.2 +/- 0.21 mM, respectively (n = 6). Coperfusion of the high-K+ solution with the Na+/K+ pump blocker ouabain (10 microM; n = 4) induced consistently spreading depression preceded by a rise in [K+](o). Finally, sporadic, isolated spots of extravasation of the fluorescent marker fluorescein isothiocyanate (FITC)-dextran preferentially circumscribed to deep cortical layers was observed in brains perfused with FITC-dextran after 5 hr in vitro. The study demonstrates that the in vitro isolated guinea pig brain is viable for studying cerebrovascular interactions and BBB permeability of compounds active in the central nervous system.
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Affiliation(s)
- L Librizzi
- Department of Neurophysiology, Istituto Nazionale Neurologico, via Celoria 11, 20133 Milan, Italy
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Fischer D, Kissel T. Histochemical characterization of primary capillary endothelial cells from porcine brains using monoclonal antibodies and fluorescein isothiocyanate-labelled lectins: implications for drug delivery. Eur J Pharm Biopharm 2001; 52:1-11. [PMID: 11438418 DOI: 10.1016/s0939-6411(01)00159-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Primary endothelial cells isolated from cerebral microvessels by combined mechanical and enzymatic treatment from porcine brains were characterized with regard to identity, purity and membrane surface characteristics. Cells were grown in culture to adherent monolayers and characterized morphologically and histochemically by their binding for fluorescently-labelled lectins and monoclonal antibodies detected by indirect immunofluorescence. The binding patterns of the cells were compared with the affinity of frozen tissue sections of porcine brain cortex for the markers. Endothelial cells in culture were characterized by the binding of von Willebrand factor, vimentin and fibronectin antibodies. They failed to react with anti-glial fibrillary acid protein, anti-galactocerebroside C and anti-neurofilament 160 antibodies characteristic for astrocytes, oligodendrocytes and neurons, respectively. Cell cultures were stained by the lectins, wheat germ agglutinin, horse gram agglutinin and soybean agglutinin, demonstrating the presence of N-acetylglucosamine and N-acetylgalactosamine residues on membrane surface. Binding sites for concanavalin A and peanut agglutinin characteristic for mannose and galactose could not be detected. Cell age and differentiation had no effect on lectin and antibody staining. Cell cultures gave staining results similar to those of microvessels in frozen tissue sections. The results of morphology, antibody and lectin staining pattern indicate that our in vitro endothelial cell culture model retained many histological characteristics observed for capillary microvessels in vivo and appears to be suitable for studying uptake and targeting properties of drug carrier systems with regard to the blood-brain barrier.
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Affiliation(s)
- D Fischer
- Department of Pharmaceutics and Biopharmacy, Philipps University of Marburg, Ketzerbach 63, 35032 Marburg, Germany
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50
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Ueno M, Sakamoto H, Kanenishi K, Onodera M, Akiguchi I, Hosokawa M. Ultrastructural and permeability features of microvessels in the hippocampus, cerebellum and pons of senescence-accelerated mice (SAM). Neurobiol Aging 2001; 22:469-78. [PMID: 11378254 DOI: 10.1016/s0197-4580(01)00213-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We previously reported that the accumulation of blood-borne radiolabelled serum albumin in brain parenchyma increased with aging, especially in senescence-accelerated mice (SAMP8), which showed age-related deficits in learning and memory. In this study, in order to examine morphological events related to the age-related increase of the brain accumulation of serum albumin, the transvascular passage of blood-borne horseradish peroxidase (HRP) and ultrastructural features of microvessels were examined in the hippocampus, cerebellum and pons of SAMP8 and SAMR1 (control) mice. Ultrastructural examination of the hippocampus showed that the staining for HRP was occasionally spreading throughout the parajunctional cytoplasm of the endothelial cell of aged SAMP8 mice, but not in young SAMP8 mice nor in SAMR1 mice. The number of vessels showing the staining reaction for HRP in the parajunctional cytoplasm of the endothelial cells in aged SAMP8 mice increased significantly compared with that in the others. Electron microscopic morphometry showed that there were no significant differences among the number of HRP-positive vesicles per unit area of the endothelial cell cytoplasm in young and old mice of both strains. The staining reaction for HRP was not seen in the basal lamina of microvessels and the perivascular neuropil in all mice examined. Perivascular lipofuscin-like granules and collagen deposits, swelling of astroglial perivascular endfeet and perivascular cells containing foamy, lipid-like droplets were frequently found in several brain regions of aged SAMP8 mice. The perivascular cells with a few lipid-like droplets and more electron-homogeneous lysosomes were occasionally seen in SAMR1 and young SAMP8, while the other findings were scarcely observed in SAMR1 and young SAMP8 mice. These findings suggest that the blood-brain barrier to HRP was preserved in microvessels in three brain regions of SAM mice but the blood microvessels showed some age-related ultrastructural alterations in SAMP8 brains. Uncontrolled passage of HRP through the parajunctional cytoplasm of the endothelial cells may partly contribute to the age-related increase of accumulation of serum albumin in SAMP8 brains.
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Affiliation(s)
- M Ueno
- Second Department of Pathology, Kagawa Medical University, 1750-1 Ikenobe, Miki-cho, Kita-gun, 761-0793, Kagawa, Japan.
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