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Zahoor SM, Ishaq S, Ahmed T. Neurotoxic effects of metals on blood brain barrier impairment and possible therapeutic approaches. VITAMINS AND HORMONES 2024; 126:1-24. [PMID: 39029969 DOI: 10.1016/bs.vh.2024.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/21/2024]
Abstract
Exposure to neurotoxic and heavy metals (Pb2+, As3+, Mn2+, Cd2+, etc) has increased over time and has shown to negatively affect brain health. Heavy metals can cross the blood brain barrier (BBB) in various ways including receptor or carrier-mediated transport, passive diffusion, or transport via gaps in the endothelial cells of the brain. In high concentrations, these metals have been shown to cause structural and functional impairment to the BBB, by inducing oxidative stress, ion dyshomeostasis, tight junction (TJ) loss, astrocyte/pericyte damage and interference of gap junctions. The structural and functional impairment of the BBB results in increased BBB permeability, which ultimately leads to accumulation of these heavy metals in the brain and their subsequent toxicity. As a result of these effects, heavy metals are correlated with various neurological disorders. The pathological effects of these heavy metals can be effectively mitigated via chelation. In addition, it is possible to treat the associated disorders by counteracting the molecular mechanisms associated with the brain and BBB impairment.
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Affiliation(s)
- Saba Mehak Zahoor
- Neurobiology Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
| | - Sara Ishaq
- Neurobiology Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan
| | - Touqeer Ahmed
- Neurobiology Laboratory, Department of Healthcare Biotechnology, Atta-ur-Rahman School of Applied Biosciences, National University of Sciences and Technology, Islamabad, Pakistan.
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2
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Korszun-Karbowniczak J, Krysiak ZJ, Saluk J, Niemcewicz M, Zdanowski R. The Progress in Molecular Transport and Therapeutic Development in Human Blood-Brain Barrier Models in Neurological Disorders. Cell Mol Neurobiol 2024; 44:34. [PMID: 38627312 PMCID: PMC11021242 DOI: 10.1007/s10571-024-01473-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2023] [Accepted: 03/18/2024] [Indexed: 04/19/2024]
Abstract
The blood-brain barrier (BBB) is responsible for maintaining homeostasis within the central nervous system (CNS). Depending on its permeability, certain substances can penetrate the brain, while others are restricted in their passage. Therefore, the knowledge about BBB structure and function is essential for understanding physiological and pathological brain processes. Consequently, the functional models can serve as a key to help reveal this unknown. There are many in vitro models available to study molecular mechanisms that occur in the barrier. Brain endothelial cells grown in culture are commonly used to modeling the BBB. Current BBB platforms include: monolayer platforms, transwell, matrigel, spheroidal, and tissue-on-chip models. In this paper, the BBB structure, molecular characteristic, as well as its dysfunctions as a consequence of aging, neurodegeneration, or under hypoxia and neurotoxic conditions are presented. Furthermore, the current modelling strategies that can be used to study BBB for the purpose of further drugs development that may reach CNS are also described.
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Affiliation(s)
- Joanna Korszun-Karbowniczak
- Laboratory of Molecular Oncology and Innovative Therapies, Military Institute of Medicine National Research Institute, 128 Szaserów Street, 04-141, Warsaw, Poland
- BioMedChem Doctoral School of the University of Lodz and Lodz Institutes of the Polish Academy of Sciences, 21/23 Matejki Street, 90-237, Lodz, Poland
| | - Zuzanna Joanna Krysiak
- Laboratory of Molecular Oncology and Innovative Therapies, Military Institute of Medicine National Research Institute, 128 Szaserów Street, 04-141, Warsaw, Poland.
| | - Joanna Saluk
- Department of General Biochemistry, Faculty of Biology and Environmental Protection, Institute of Biochemistry, University of Lodz, 68 Narutowicza Street, 90-136, Lodz, Poland
| | - Marcin Niemcewicz
- Biohazard Prevention Centre, Faculty of Biology and Environmental Protection, University of Lodz, 68 Narutowicza Street, 90-136, Lodz, Poland
| | - Robert Zdanowski
- Laboratory of Molecular Oncology and Innovative Therapies, Military Institute of Medicine National Research Institute, 128 Szaserów Street, 04-141, Warsaw, Poland
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Leal-Nazaré CG, Arrifano GP, Lopes-Araújo A, Santos-Sacramento L, Barthelemy JL, Soares-Silva I, Crespo-Lopez ME, Augusto-Oliveira M. Methylmercury neurotoxicity: Beyond the neurocentric view. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:170939. [PMID: 38365040 DOI: 10.1016/j.scitotenv.2024.170939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 02/09/2024] [Accepted: 02/10/2024] [Indexed: 02/18/2024]
Abstract
Mercury is a highly toxic metal widely used in human activities worldwide, therefore considered a global public health problem. Many cases of mercury intoxication have occurred in history and represent a huge challenge nowadays. Of particular importance is its methylated form, methylmercury (MeHg). This mercurial species induces damage to several organs in the human body, especially to the central nervous system. Neurological impairments such as executive, memory, motor and visual deficits are associated with MeHg neurotoxicity. Molecular mechanisms involved in MeHg-induced neurotoxicity include excitotoxicity due to glutamatergic imbalance, disturbance in calcium homeostasis and oxidative balance, failure in synaptic support, and inflammatory response. Although neurons are largely affected by MeHg intoxication, they only represent half of the brain cells. Glial cells represent roughly 50 % of the brain cells and are key elements in the functioning of the central nervous system. Particularly, astrocytes and microglia are deeply involved in MeHg-induced neurotoxicity, resulting in distinct neurological outcomes depending on the context. In this review, we discuss the main findings on astroglial and microglial involvement as mediators of neuroprotective and neurotoxic responses to MeHg intoxication. The literature shows that these responses depend on chemical and morphophysiological features, thus, we present some insights for future investigations, considering the particularities of the context, including time and dose of exposure, brain region, and species of study.
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Affiliation(s)
- Caio Gustavo Leal-Nazaré
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Gabriela P Arrifano
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Amanda Lopes-Araújo
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Leticia Santos-Sacramento
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Jean Ludger Barthelemy
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Isabela Soares-Silva
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil
| | - Maria Elena Crespo-Lopez
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil.
| | - Marcus Augusto-Oliveira
- Laboratório de Farmacologia Molecular, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, PA, Brazil.
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Bramatti I, Aschner M, Branco V, Carvalho C. Exposure of human glioblastoma cells to thimerosal inhibits the thioredoxin system and decreases tumor growth-related factors. Toxicol Appl Pharmacol 2024; 484:116844. [PMID: 38325586 DOI: 10.1016/j.taap.2024.116844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 01/25/2024] [Accepted: 02/04/2024] [Indexed: 02/09/2024]
Abstract
Glioblastoma multiforme (GBM) is the most common, aggressive, and fatal primary malignant brain tumor in adults. The therapeutic efficacy of temozolomide (TMZ) is limited owing to frequent treatment resistance. The latter is in part related to the overexpression of redox systems such as the thioredoxin system. This system is fundamental for cell survival and proliferation, regulating hypoxia inducible factor-1alpha (HIF-1α) activity, in turn controlling vascular endothelial growth factor (VEGF), which is indispensable for tumor invasiveness, angiogenesis and microenvironment maintenance. HIF-1α can also be regulated by the signal transducer and activator of transcription 3 (STAT3), an oncogene stimulated by pro-inflammatory cytokines and growth factors. The thioredoxin system has several known inhibitors including mercury compounds such as Thimerosal (TmHg) which readily crosses the blood-brain barrier (BBB) and accumulates in the brain. Though previously used in various applications epidemiological evidence on TmHg's neurotoxicity is lacking. The objective of this study was to verify whether thimerosal is a suitable candidate for hard repurposing to control glioblastoma; therefore, the effects of this molecule were evaluated in human GBM (U87) cells. Our novel results show that TmHg decreased cellular viability (>50%) and migration (up to 90% decrease in wound closure), reduced thioredoxin reductase (TrxR/TXNRD1) and thioredoxin (Trx) activity, and increased reactive oxygen species (ROS) generation. Moreover, TmHg reduced HIF-1α expression (35%) as observed by immunofluorescence. Co-exposure of U87 cells to TmHg and TMZ reduced HIF-1α, VEGF, and phosphorylated STAT3. Consequently, TmHg alone or combined with chemotherapeutic drugs can reduce neoangiogenesis and ameliorate glioblastoma progression and treatment.
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Affiliation(s)
- Isabella Bramatti
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, Lisboa 1649-003, Portugal
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Vasco Branco
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, Lisboa 1649-003, Portugal; Department of Pharmaceutical Sciences and Medicines, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Cristina Carvalho
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Prof. Gama Pinto, Lisboa 1649-003, Portugal; Department of Pharmaceutical Sciences and Medicines, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal.
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Dürig J, Calcagni M, Buschmann J. Transition metals in angiogenesis - A narrative review. Mater Today Bio 2023; 22:100757. [PMID: 37593220 PMCID: PMC10430620 DOI: 10.1016/j.mtbio.2023.100757] [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: 06/01/2023] [Revised: 07/14/2023] [Accepted: 07/31/2023] [Indexed: 08/19/2023] Open
Abstract
The aim of this paper is to offer a narrative review of the literature regarding the influence of transition metals on angiogenesis, excluding lanthanides and actinides. To our knowledge there are not any reviews up to date offering such a summary, which inclined us to write this paper. Angiogenesis describes the process of blood vessel formation, which is an essential requirement for human growth and development. When the complex interplay between pro- and antiangiogenic mediators falls out of balance, angiogenesis can quickly become harmful. As it is so fundamental, both its inhibition and enhancement take part in various diseases, making it a target for therapeutic treatments. Current methods come with limitations, therefore, novel agents are constantly being researched, with metal agents offering promising results. Various transition metals have already been investigated in-depth, with studies indicating both pro- and antiangiogenic properties, respectively. The transition metals are being applied in various formulations, such as nanoparticles, complexes, or scaffold materials. Albeit the increasing attention this field is receiving, there remain many unanswered questions, mostly regarding the molecular mechanisms behind the observed effects. Notably, approximately half of all the transition metals have not yet been investigated regarding potential angiogenic effects. Considering the promising results which have already been established, it should be of great interest to begin investigating the remaining elements whilst also further analyzing the established effects.
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Affiliation(s)
- Johannes Dürig
- University of Zürich, Faculty of Medicine, Pestalozzistrasse 3, 8032, Zurich, Switzerland
- University Hospital of Zürich, Department of Plastic Surgery and Hand Surgery, Rämistrasse 100, 8091, Zürich, Switzerland
| | - Maurizio Calcagni
- University Hospital of Zürich, Department of Plastic Surgery and Hand Surgery, Rämistrasse 100, 8091, Zürich, Switzerland
| | - Johanna Buschmann
- University Hospital of Zürich, Department of Plastic Surgery and Hand Surgery, Rämistrasse 100, 8091, Zürich, Switzerland
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Aschner M, Skalny AV, Lu R, Santamaria A, Zhou JC, Ke T, Karganov MY, Tsatsakis A, Golokhvast KS, Bowman AB, Tinkov AA. The role of hypoxia-inducible factor 1 alpha (HIF-1α) modulation in heavy metal toxicity. Arch Toxicol 2023; 97:1299-1318. [PMID: 36933023 DOI: 10.1007/s00204-023-03483-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 03/02/2023] [Indexed: 03/19/2023]
Abstract
Hypoxia-inducible factor 1 (HIF-1) is an oxygen-sensing transcriptional regulator orchestrating a complex of adaptive cellular responses to hypoxia. Several studies have demonstrated that toxic metal exposure may also modulate HIF-1α signal transduction pathway, although the existing data are scarce. Therefore, the present review aims to summarize the existing data on the effects of toxic metals on HIF-1 signaling and the potential underlying mechanisms with a special focus on prooxidant effect of the metals. The particular effect of metals was shown to be dependent on cell type, varying from down- to up-regulation of HIF-1 pathway. Inhibition of HIF-1 signaling may contribute to impaired hypoxic tolerance and adaptation, thus promoting hypoxic damage in the cells. In contrast, its metal-induced activation may result in increased tolerance to hypoxia through increased angiogenesis, thus promoting tumor growth and contributing to carcinogenic effect of heavy metals. Up-regulation of HIF-1 signaling is mainly observed upon Cr, As, and Ni exposure, whereas Cd and Hg may both stimulate and inhibit HIF-1 pathway. The mechanisms underlying the influence of toxic metal exposure on HIF-1 signaling involve modulation of prolyl hydroxylases (PHD2) activity, as well as interference with other tightly related pathways including Nrf2, PI3K/Akt, NF-κB, and MAPK signaling. These effects are at least partially mediated by metal-induced ROS generation. Hypothetically, maintenance of adequate HIF-1 signaling upon toxic metal exposure through direct (PHD2 modulation) or indirect (antioxidant) mechanisms may provide an additional strategy for prevention of adverse effects of metal toxicity.
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Affiliation(s)
- Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Anatoly V Skalny
- IM Sechenov First Moscow State Medical University (Sechenov University), 119435, Moscow, Russia
| | - Rongzhu Lu
- Department of Preventive Medicine and Public Health Laboratory Science, School of Medicine, Jiangsu University, Zhenjiang, 212013, Jiangsu, China
| | - Abel Santamaria
- Laboratorio de Aminoácidos Excitadores/Laboratorio de Neurofarmacología Molecular y Nanotecnología, Instituto Nacional de Neurología y Neurocirugía, 14269, Mexico City, Mexico
| | - Ji-Chang Zhou
- School of Public Health (Shenzhen), Sun Yat-Sen University, Shenzhen, 518100, China
| | - Tao Ke
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | | | - Aristides Tsatsakis
- IM Sechenov First Moscow State Medical University (Sechenov University), 119435, Moscow, Russia.,Laboratory of Toxicology, Medical School, University of Crete, Voutes, 700 13, Heraklion, Crete, Greece
| | - Kirill S Golokhvast
- Siberian Federal Scientific Centre of Agrobiotechnologies of the Russian Academy of Sciences, Krasnoobsk, Russia
| | - Aaron B Bowman
- School of Health Sciences, Purdue University, West Lafayette, USA
| | - Alexey A Tinkov
- IM Sechenov First Moscow State Medical University (Sechenov University), 119435, Moscow, Russia. .,Laboratory of Ecobiomonitoring and Quality Control, Yaroslavl State University, 150003, Yaroslavl, Russia.
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Abu-Zeid EH, Khalifa BA, Elewa YHA, Arisha AH, Ismail TA, Hendam BM, Abdel-Hamid SE. Bee venom Apis mellifera lamarckii rescues blood brain barrier damage and neurobehavioral changes induced by methyl mercury via regulating tight junction proteins expression in rat cerebellum. Food Chem Toxicol 2021; 154:112309. [PMID: 34062221 DOI: 10.1016/j.fct.2021.112309] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/21/2021] [Accepted: 05/25/2021] [Indexed: 12/22/2022]
Abstract
The objective of the current study is to investigate the protective effect of Egyptian bee venom (BV) against methyl mercury chloride (MMC) induced blood-brain barrier (BBB) damage and neurobehavioral changes. Eighty male Sprague-Dawley rats were randomly grouped into 1st control (C), 2nd BV (0.5 mg/kg S/C for14 days), 3rd MMC (6.7 mg/kg orally/14 days), and 4th MMC + BV group. MMC exposure significantly altered rat cognitive behavior, auditory startle habituation, and swimming performance, increased the exploratory, grooming, and stereotypic behavior. MMC significantly impaired BBB integrity via induction of inflammation, oxidative stress, and down-regulation of tight junction proteins genes (TJPs) mRNA expression levels: Occludin (OCC), Claudins-5 (CLDN5), Zonula occludens-1 (ZO-1), while up-regulated the transforming growth factor-beta (TGF-β) mRNA expression levels. MMC revealed a significantly higher percentage of IgG positive area ratio, a higher index ratio of Iba1, Sox10, and ss-DNA, while index ratio of CD31, neurofilament, and pan neuron showed a significant reduction. Administration of BV significantly regulates the MMC altered behavioral responses, TJPs relative mRNA expression, and the immune-expression markers for specific neural cell types. It could be concluded for the first time that BV retains a promising in vivo protection against MMC-induced BBB dysfunction and neurobehavioral toxicity.
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Affiliation(s)
- Ehsan H Abu-Zeid
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Zagazig University, 44511, Egypt.
| | - Bouthaina A Khalifa
- Department of Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Cairo University, Cairo, 12211, Egypt
| | - Yaser H A Elewa
- Department of Histology and Cytology, Faculty of Veterinary Medicine, Zagazig University, 44511, Egypt; Laboratory of Anatomy, Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
| | - Ahmed H Arisha
- Department of Animal Physiology and Biochemistry, Faculty of Veterinary Medicine, Badr University in Cairo (BUC), Badr City, Cairo, Egypt; Department of Physiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, 44511, Egypt
| | - Tamer A Ismail
- Department of Clinical Laboratory Sciences, Turabah University College, Taif University, P.O. Box 11099, Taif, 21944, Saudi Arabia
| | - Basma M Hendam
- Department of Husbandry and Development of Animal Wealth, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt
| | - Shereen El Abdel-Hamid
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Zagazig University, Zagazig, 44511, Egypt
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Revisiting Astrocytic Roles in Methylmercury Intoxication. Mol Neurobiol 2021; 58:4293-4308. [PMID: 33990914 DOI: 10.1007/s12035-021-02420-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 05/04/2021] [Indexed: 02/06/2023]
Abstract
Intoxication by heavy metals such as methylmercury (MeHg) is recognized as a global health problem, with strong implications in central nervous system pathologies. Most of these neuropathological conditions involve vascular, neurotransmitter recycling, and oxidative balance disruption leading to accelerated decline in fine balance, and learning, memory, and visual processes as main outcomes. Besides neurons, astrocytes are involved in virtually all the brain processes and perform important roles in neurological response following injuries. Due to astrocytes' strategic functions in brain homeostasis, these cells became the subject of several studies on MeHg intoxication. The most heterogenous glial cells, astrocytes, are composed of plenty of receptors and transporters to dialogue with neurons and other cells and to monitor extracellular environment responding tightly through fluctuation of cytosolic ions. The overall toxicity of MeHg might be determined on the basis of the balance between MeHg-mediated injury to neurons and protective responses from astrocytes. Although the role of neurons in MeHg intoxication is relatively well-established, the role of the astrocytes is only beginning to be understood. In this review, we update the information on astroglial modulation of the MeHg-induced neurotoxicity, providing remarks on their protective and deleterious roles and insights for future studies.
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Girolamo F, de Trizio I, Errede M, Longo G, d'Amati A, Virgintino D. Neural crest cell-derived pericytes act as pro-angiogenic cells in human neocortex development and gliomas. Fluids Barriers CNS 2021; 18:14. [PMID: 33743764 PMCID: PMC7980348 DOI: 10.1186/s12987-021-00242-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 02/13/2021] [Indexed: 02/07/2023] Open
Abstract
Central nervous system diseases involving the parenchymal microvessels are frequently associated with a ‘microvasculopathy’, which includes different levels of neurovascular unit (NVU) dysfunction, including blood–brain barrier alterations. To contribute to the understanding of NVU responses to pathological noxae, we have focused on one of its cellular components, the microvascular pericytes, highlighting unique features of brain pericytes with the aid of the analyses carried out during vascularization of human developing neocortex and in human gliomas. Thanks to their position, centred within the endothelial/glial partition of the vessel basal lamina and therefore inserted between endothelial cells and the perivascular and vessel-associated components (astrocytes, oligodendrocyte precursor cells (OPCs)/NG2-glia, microglia, macrophages, nerve terminals), pericytes fulfil a central role within the microvessel NVU. Indeed, at this critical site, pericytes have a number of direct and extracellular matrix molecule- and soluble factor-mediated functions, displaying marked phenotypical and functional heterogeneity and carrying out multitasking services. This pericytes heterogeneity is primarily linked to their position in specific tissue and organ microenvironments and, most importantly, to their ontogeny. During ontogenesis, pericyte subtypes belong to two main embryonic germ layers, mesoderm and (neuro)ectoderm, and are therefore expected to be found in organs ontogenetically different, nonetheless, pericytes of different origin may converge and colonize neighbouring areas of the same organ/apparatus. Here, we provide a brief overview of the unusual roles played by forebrain pericytes in the processes of angiogenesis and barriergenesis by virtue of their origin from midbrain neural crest stem cells. A better knowledge of the ontogenetic subpopulations may support the understanding of specific interactions and mechanisms involved in pericyte function/dysfunction, including normal and pathological angiogenesis, thereby offering an alternative perspective on cell subtype-specific therapeutic approaches. ![]()
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Affiliation(s)
- Francesco Girolamo
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, Human Anatomy and Histology Unit, University of Bari School of Medicine, Bari, Italy.
| | - Ignazio de Trizio
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, Human Anatomy and Histology Unit, University of Bari School of Medicine, Bari, Italy.,Intensive Care Unit, Department of Intensive Care, Regional Hospital of Lugano, Ente Ospedaliero Cantonale, Lugano, Switzerland
| | - Mariella Errede
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, Human Anatomy and Histology Unit, University of Bari School of Medicine, Bari, Italy
| | - Giovanna Longo
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, Molecular Biology Unit, University of Bari School of Medicine, Bari, Italy
| | - Antonio d'Amati
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, Human Anatomy and Histology Unit, University of Bari School of Medicine, Bari, Italy.,Department of Emergency and Organ Transplantation, Pathology Section, University of Bari School of Medicine, Bari, Italy
| | - Daniela Virgintino
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, Human Anatomy and Histology Unit, University of Bari School of Medicine, Bari, Italy
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10
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Girolamo F, de Trizio I, Errede M, Longo G, d’Amati A, Virgintino D. Neural crest cell-derived pericytes act as pro-angiogenic cells in human neocortex development and gliomas. Fluids Barriers CNS 2021. [DOI: 10.1186/s12987-021-00242-7 union select null--] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractCentral nervous system diseases involving the parenchymal microvessels are frequently associated with a ‘microvasculopathy’, which includes different levels of neurovascular unit (NVU) dysfunction, including blood–brain barrier alterations. To contribute to the understanding of NVU responses to pathological noxae, we have focused on one of its cellular components, the microvascular pericytes, highlighting unique features of brain pericytes with the aid of the analyses carried out during vascularization of human developing neocortex and in human gliomas. Thanks to their position, centred within the endothelial/glial partition of the vessel basal lamina and therefore inserted between endothelial cells and the perivascular and vessel-associated components (astrocytes, oligodendrocyte precursor cells (OPCs)/NG2-glia, microglia, macrophages, nerve terminals), pericytes fulfil a central role within the microvessel NVU. Indeed, at this critical site, pericytes have a number of direct and extracellular matrix molecule- and soluble factor-mediated functions, displaying marked phenotypical and functional heterogeneity and carrying out multitasking services. This pericytes heterogeneity is primarily linked to their position in specific tissue and organ microenvironments and, most importantly, to their ontogeny. During ontogenesis, pericyte subtypes belong to two main embryonic germ layers, mesoderm and (neuro)ectoderm, and are therefore expected to be found in organs ontogenetically different, nonetheless, pericytes of different origin may converge and colonize neighbouring areas of the same organ/apparatus. Here, we provide a brief overview of the unusual roles played by forebrain pericytes in the processes of angiogenesis and barriergenesis by virtue of their origin from midbrain neural crest stem cells. A better knowledge of the ontogenetic subpopulations may support the understanding of specific interactions and mechanisms involved in pericyte function/dysfunction, including normal and pathological angiogenesis, thereby offering an alternative perspective on cell subtype-specific therapeutic approaches.
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11
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Olung NF, Aluko OM, Jeje SO, Adeagbo AS, Ijomone OM. Vascular Dysfunction in the Brain; Implications for Heavy Metal Exposures. Curr Hypertens Rev 2021; 17:5-13. [PMID: 33632106 DOI: 10.2174/1573402117666210225085528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/24/2020] [Accepted: 12/01/2020] [Indexed: 11/22/2022]
Abstract
Normal or diseased conditions that alter the brain's requirement for oxygen and nutrients via alterations to neurovascular coupling have an impact on the level of the neurovascular unit; comprising neuronal, glial and vascular components. The communications between the components of the neurovascular unit are precise and accurate for its functions; hence a minute disturbance can result in neurovascular dysfunction. Heavy metals such as cadmium, mercury, and lead have been identified to increase the vulnerability of the neurovascular unit to damage. This review examines the role of heavy metals in neurovascular dysfunctions and the possible mechanisms by which these metals act. Risk factors ranging from lifestyle, environment, genetics, infections, and physiologic ageing involved in neurological dysfunctions were highlighted, while stroke was discussed as the prevalent consequence of neurovascular dysfunctions. Furthermore, the role of these heavy metals in the pathogenesis of stroke consequently pinpoints the importance of understanding the mechanisms of neurovascular damage in a bid to curb the occurrence of neurovascular dysfunctions.
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Affiliation(s)
- Nzube F Olung
- The Neuro-Lab, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Oritoke M Aluko
- The Neuro-Lab, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Sikirullai O Jeje
- Department of Physiology, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Ayotunde S Adeagbo
- Department of Physiology, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
| | - Omamuyovwi M Ijomone
- The Neuro-Lab, School of Health and Health Technology, Federal University of Technology, Akure, Nigeria
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Chang J, Yang B, Zhou Y, Yin C, Liu T, Qian H, Xing G, Wang S, Li F, Zhang Y, Chen D, Aschner M, Lu R. Acute Methylmercury Exposure and the Hypoxia-Inducible Factor-1α Signaling Pathway under Normoxic Conditions in the Rat Brain and Astrocytes in Vitro. ENVIRONMENTAL HEALTH PERSPECTIVES 2019; 127:127006. [PMID: 31850806 PMCID: PMC6957278 DOI: 10.1289/ehp5139] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 11/07/2019] [Accepted: 11/18/2019] [Indexed: 06/10/2023]
Abstract
BACKGROUND As a ubiquitous environmental pollutant, methylmercury (MeHg) induces toxic effects in the nervous system, one of its main targets. However, the exact mechanisms of its neurotoxicity have not been fully elucidated. Hypoxia-inducible factor- 1 α (HIF- 1 α ), a transcription factor, plays a crucial role in adaptive and cytoprotective responses in cells and is involved in cell survival, proliferation, apoptosis, inflammation, angiogenesis, glucose metabolism, erythropoiesis, and other physiological activities. OBJECTIVES The aim of this study was to explore the role of HIF- 1 α in response to acute MeHg exposure in rat brain and primary cultured astrocytes to improve understanding of the mechanisms of MeHg-induced neurotoxicity and the development of effective neuroprotective strategies. METHODS Primary rat astrocytes were treated with MeHg (0 - 10 μ M ) for 0.5 h . Cell proliferation and cytotoxicity were assessed with a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl diphenyltetrazolium bromide (MTT) assay and a lactate dehydrogenase (LDH) release assay, respectively. Reactive oxygen species (ROS) levels were analyzed to assess the level of oxidative stress using 2',7'-dichlorofluorescin diacetate (DCFH-DA) fluorescence. HIF- 1 α , and its downstream proteins, glucose transporter 1 (GLUT-1), erythropoietin (EPO), and vascular endothelial growth factor A (VEGF-A) were analyzed by means of Western blotting. Real-time PCR was used to detect the expression of HIF- 1 α mRNA. Pretreatment with protein synthesis inhibitor (CHX), proteasome inhibitor (MG132), or proline hydroxylase inhibitor (DHB) were applied to explore the possible mechanisms of HIF- 1 α inhibition by MeHg. To investigate the role of HIF- 1 α in MeHg-induced neurotoxicity, cobalt chloride (CoC l 2 ), 2-methoxyestradiol (2-MeOE2), small interfering RNA (siRNA) transfection and adenovirus overexpression were used. Pretreatment with N-acetyl-L-cysteine (NAC) and vitamin E (Trolox) were used to investigate the putative role of oxidative stress in MeHg-induced alterations in HIF- 1 α levels. The expression of HIF- 1 α and related downstream proteins was detected in adult rat brain exposed to MeHg (0 - 10 mg / kg ) for 0.5 h in vivo. RESULTS MeHg caused lower cell proliferation and higher cytotoxicity in primary rat astrocytes in a time- and concentration-dependent manner. In comparison with the control cells, exposure to 10 μ M MeHg for 0.5 h significantly inhibited the expression of astrocytic HIF- 1 α , and the downstream genes GLUT-1, EPO, and VEGF-A (p < 0.05 ), in the absence of a significant decrease in HIF- 1 α mRNA levels. When protein synthesis was inhibited by CHX, MeHg promoted the degradation rate of HIF- 1 α . MG132 and DHB significantly blocked the MeHg-induced decrease in HIF- 1 α expression (p < 0.05 ). Overexpression of HIF- 1 α significantly attenuated the decline in MeHg-induced cell proliferation, whereas the inhibition of HIF- 1 α significantly increased the decline in cell proliferation (p < 0.05 ). NAC and Trolox, two established antioxidants, reversed the MeHg-induced decline in HIF- 1 α protein levels and the decrease in cell proliferation (p < 0.05 ). MeHg suppressed the expression of HIF- 1 α and related downstream target proteins in adult rat brain. DISCUSSION MeHg induced a significant reduction in HIF- 1 α protein by activating proline hydroxylase (PHD) and the ubiquitin proteasome system (UPS) in primary rat astrocytes. Additionally, ROS scavenging by antioxidants played a neuroprotective role via increasing HIF- 1 α expression in response to MeHg toxicity. Moreover, we established that up-regulation of HIF- 1 α might serve to mitigate the acute toxicity of MeHg in astrocytes, affording a novel therapeutic target for future exploration. https://doi.org/10.1289/EHP5139.
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Affiliation(s)
- Jie Chang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Bobo Yang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Yun Zhou
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Changsheng Yin
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
- Institute of Life Sciences, Jiangsu University, Zhenjiang, China
| | - Tingting Liu
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Hai Qian
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Guangwei Xing
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Suhua Wang
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Fang Li
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
| | - Yubin Zhang
- Department of Occupational Health and Toxicology, School of Public Health, Fudan University, Shanghai, China
| | - Da Chen
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, China
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Rongzhu Lu
- Department of Preventive Medicine and Public Health Laboratory Sciences, School of Medicine, Jiangsu University, Zhenjiang, China
- Center for Experimental Research, Kunshan Hospital Affiliated to Jiangsu University, Kunshan, China
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Takahashi T, Shimohata T. Vascular Dysfunction Induced by Mercury Exposure. Int J Mol Sci 2019; 20:E2435. [PMID: 31100949 PMCID: PMC6566353 DOI: 10.3390/ijms20102435] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/10/2019] [Accepted: 05/16/2019] [Indexed: 12/15/2022] Open
Abstract
Methylmercury (MeHg) causes severe damage to the central nervous system, and there is increasing evidence of the association between MeHg exposure and vascular dysfunction, hemorrhage, and edema in the brain, but not in other organs of patients with acute MeHg intoxication. These observations suggest that MeHg possibly causes blood-brain barrier (BBB) damage. MeHg penetrates the BBB into the brain parenchyma via active transport systems, mainly the l-type amino acid transporter 1, on endothelial cell membranes. Recently, exposure to mercury has significantly increased. Numerous reports suggest that long-term low-level MeHg exposure can impair endothelial function and increase the risks of cardiovascular disease. The most widely reported mechanism of MeHg toxicity is oxidative stress and related pathways, such as neuroinflammation. BBB dysfunction has been suggested by both in vitro and in vivo models of MeHg intoxication. Therapy targeted at both maintaining the BBB and suppressing oxidative stress may represent a promising therapeutic strategy for MeHg intoxication. This paper reviews studies on the relationship between MeHg exposure and vascular dysfunction, with a special emphasis on the BBB.
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Affiliation(s)
- Tetsuya Takahashi
- Department of Neurology, National Hospital Organization Nishiniigata Chuo Hospital, Niigata 950-2085, Japan.
| | - Takayoshi Shimohata
- Department of Neurology, Gifu University Graduate School of Medicine, Gifu 501-1194, Japan.
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Shao Y, Wang L, Langlois P, Mironov G, Chan HM. Proteome changes in methylmercury-exposed mouse primary cerebellar granule neurons and astrocytes. Toxicol In Vitro 2019; 57:96-104. [PMID: 30776503 DOI: 10.1016/j.tiv.2019.02.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 01/14/2019] [Accepted: 02/14/2019] [Indexed: 11/29/2022]
Abstract
Methylmercury (MeHg) is a neurotoxicant, with the cerebellum as the main target of toxicity; however, the toxic effects of MeHg on specific cell types remain unclear. Here, primary cerebellar granule neurons (CGNs) and cerebellar astrocytes were isolated and analyzed for total mercury accumulation, cellular reactive oxygen species (ROS) production, and whole-cell proteome expression after exposure to 0-10 μM MeHg for 24 h. Intracellular mercury and ROS levels showed dose-dependent increases. Mercury accumulation was greater in CGNs than astrocytes. The proteomic analysis identified a total of 1966 and 3214 proteins in CGNs and astrocytes, among which 183 and 262 proteins were differentially expressed after mercury exposure, respectively. Enrichment analysis revealed mitochondrial-associated organelles as the main targets of MeHg in both cell types. Whereas multiple functions/pathways were affected in CGNs, the oxidation-reduction process was the most significantly changed function/pathway in astrocytes. CGNs were more sensitive to MeHg-mediated neurotoxicity than astrocytes. The two cell types showed distinct mechanistic responses to MeHg. In astrocytes, the mitochondrion was the primary target of toxicity, resulting in increases in oxidation-reduction process responses. In CGNs, the neurotrophin signaling pathway, cytoskeleton, cAMP signaling pathway, and thyroid hormone signaling pathway were affected.
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Affiliation(s)
- Yueting Shao
- School of Public Health, Guangzhou Medical University, Guangzhou, China
| | - Lewis Wang
- Department of Biology, University of Ottawa, Canada
| | | | - Gleb Mironov
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Canada
| | - Hing Man Chan
- Department of Biology, University of Ottawa, Canada.
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Yoshida E, Kurita M, Eto K, Kumagai Y, Kaji T. Methylmercury promotes prostacyclin release from cultured human brain microvascular endothelial cells via induction of cyclooxygenase-2 through activation of the EGFR-p38 MAPK pathway by inhibiting protein tyrosine phosphatase 1B activity. Toxicology 2017; 392:40-46. [PMID: 28958600 DOI: 10.1016/j.tox.2017.09.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 09/22/2017] [Accepted: 09/24/2017] [Indexed: 12/26/2022]
Abstract
Methylmercury is an environmental pollutant that exhibits neurotoxicity when ingested, primarily in the form of neuropathological lesions that localize along deep sulci and fissures, in addition to edematous and inflammatory changes in patient cerebrums. These conditions been known to give rise to a variety of ailments that have come to be collectively termed Minamata disease. Since prostaglandins I2 and E2 (PGI2 and PGE2) increase vascular permeability and contribute to the progression of inflammatory changes, we hypothesize that methylmercury induces the synthesis of these prostaglandins in brain microvascular endothelial cells and pericytes. To test this theory, human brain microvascular endothelial cells and pericytes were cultured and treated with methylmercury, after which the PGI2 and PGE2 released from endothelial cells and/or pericytes were quantified by enzyme-linked immunosorbent assay while protein and mRNA expressions in endothelial cells were analyzed by western blot analysis and real-time reverse transcription polymerase chain reaction, respectively. Experimental results indicate that methylmercury inhibits the activity of protein tyrosine phosphatase 1B, which in turn activates the epidermal growth factor receptor-p38 mitogen-activated protein kinase pathway that induces cyclooxygenase-2 expression. It was also found that the cyclic adenosine 3',5'-monophosphate pathway, which can be activated by PGI2 and PGE2, is involved in methylmercury-induced cyclooxygenase-2 expression. Since it appears that protein tyrosine phosphatase 1 B serves as a sensor protein for methylmercury in these mechanisms, it is our belief that the results of the present study may provide additional insights into the molecular mechanisms responsible for edematous and inflammatory changes in the cerebrum of patients with Minamata disease.
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Affiliation(s)
- Eiko Yoshida
- Department of Environmental Health, Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda 278-8510, Japan
| | - Masaru Kurita
- Department of Environmental Health, Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda 278-8510, Japan
| | - Komyo Eto
- Health and Nursing Facilities for the Aged, Jushindai, Shinwakai, 272 Ikura Kitakata, Tamana 865-0041, Japan
| | - Yoshito Kumagai
- Environmental Biology Section, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575, Japan
| | - Toshiyuki Kaji
- Department of Environmental Health, Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda 278-8510, Japan.
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The Putative Role of Environmental Mercury in the Pathogenesis and Pathophysiology of Autism Spectrum Disorders and Subtypes. Mol Neurobiol 2017; 55:4834-4856. [DOI: 10.1007/s12035-017-0692-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Accepted: 07/13/2017] [Indexed: 01/28/2023]
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Takahashi T, Fujimura M, Koyama M, Kanazawa M, Usuki F, Nishizawa M, Shimohata T. Methylmercury Causes Blood-Brain Barrier Damage in Rats via Upregulation of Vascular Endothelial Growth Factor Expression. PLoS One 2017; 12:e0170623. [PMID: 28118383 PMCID: PMC5261729 DOI: 10.1371/journal.pone.0170623] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 01/07/2017] [Indexed: 01/24/2023] Open
Abstract
Clinical manifestations of methylmercury (MeHg) intoxication include cerebellar ataxia, concentric constriction of visual fields, and sensory and auditory disturbances. The symptoms depend on the site of MeHg damage, such as the cerebellum and occipital lobes. However, the underlying mechanism of MeHg-induced tissue vulnerability remains to be elucidated. In the present study, we used a rat model of subacute MeHg intoxication to investigate possible MeHg-induced blood-brain barrier (BBB) damage. The model was established by exposing the rats to 20-ppm MeHg for up to 4 weeks; the rats exhibited severe cerebellar pathological changes, although there were no significant differences in mercury content among the different brain regions. BBB damage in the cerebellum after MeHg exposure was confirmed based on extravasation of endogenous immunoglobulin G (IgG) and decreased expression of rat endothelial cell antigen-1. Furthermore, expression of vascular endothelial growth factor (VEGF), a potent angiogenic growth factor, increased markedly in the cerebellum and mildly in the occipital lobe following MeHg exposure. VEGF expression was detected mainly in astrocytes of the BBB. Intravenous administration of anti-VEGF neutralizing antibody mildly reduced the rate of hind-limb crossing signs observed in MeHg-exposed rats. In conclusion, we demonstrated for the first time that MeHg induces BBB damage via upregulation of VEGF expression at the BBB in vivo. Further studies are required in order to determine whether treatment targeted at VEGF can ameliorate MeHg-induced toxicity.
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Affiliation(s)
- Tetsuya Takahashi
- Department of Neurology, Brain Research Institute, Niigata University, Niigata, Niigata, Japan
| | - Masatake Fujimura
- Department of Basic Medical Sciences, National Institute for Minamata Disease, Minamata, Kumamoto, Japan
| | - Misaki Koyama
- Department of Neurology, Brain Research Institute, Niigata University, Niigata, Niigata, Japan
| | - Masato Kanazawa
- Department of Neurology, Brain Research Institute, Niigata University, Niigata, Niigata, Japan
| | - Fusako Usuki
- Department of Clinical Medicine, National Institute for Minamata Disease, Minamata, Kumamoto, Japan
| | - Masatoyo Nishizawa
- Department of Neurology, Brain Research Institute, Niigata University, Niigata, Niigata, Japan
| | - Takayoshi Shimohata
- Department of Neurology, Brain Research Institute, Niigata University, Niigata, Niigata, Japan
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Hirooka T, Yoshida E, Eto K, Kaji T. Methylmercury induces hyaluronan synthesis in cultured human brain microvascular endothelial cells and pericytes via different mechanisms. J Toxicol Sci 2017; 42:329-333. [DOI: 10.2131/jts.42.329] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Takashi Hirooka
- Department of Environmental Health, Faculty of Pharmaceutical Sciences, Tokyo University of Science
- Kanagawa Academy of Science and Technology, KSP
| | - Eiko Yoshida
- Department of Environmental Health, Faculty of Pharmaceutical Sciences, Tokyo University of Science
| | - Komyo Eto
- Health and Nursing Facilities for the Aged, Jushindai
| | - Toshiyuki Kaji
- Department of Environmental Health, Faculty of Pharmaceutical Sciences, Tokyo University of Science
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Wu Q, Jing Y, Yuan X, Li B, Wang B, Liu M, Li H, Xiu R. The distinct abilities of tube-formation and migration between brain and spinal cord microvascular pericytes in rats. Clin Hemorheol Microcirc 2016; 60:231-40. [PMID: 24946754 DOI: 10.3233/ch-141856] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Pericytes are contractile cells that wrap around the endothelial cells of capillaries throughout the body. They play an important role in regulating the blood brain barrier (BBB) and blood spinal cord barrier (BSCB). The differences between brain and spinal cord microvascular endothelial cells have been investigated. However, no report has elucidated the similarities and differences between brain microvascular pericytes (BMPs) and spinal cord microvascular pericytes (SCMPs) in vitro. The similarities were found between the two types of pericytes not only in the proliferation ability but also in the expression of toll like receptor 4. On the other hand, BMPs showed more than 2 fold in tubular length formation compared with SCMPs. The number of migratory SCMPs was larger than that of migratory BMPs. The expressions of connexin 43 and vascular endothelial growth factor (VEGF) in BMPs were increased compared with those in SCMPs, while SCMPs expressed more desmin and N-cadherin than BMPs. The abilities of tube-formation and migration between BMPs and SCMPs were markedly different, which might be mediated by VEGF, connexin 43, N-cadherin and desmin. These distinguishing features may reflect the more widespread differences between the BBB and BSCB which directly impact pathophysiological processes in various major diseases.
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Schumacher L, Abbott LC. Effects of methyl mercury exposure on pancreatic beta cell development and function. J Appl Toxicol 2016; 37:4-12. [PMID: 27594070 DOI: 10.1002/jat.3381] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/29/2016] [Accepted: 07/31/2016] [Indexed: 12/31/2022]
Abstract
Methyl mercury is an environmental contaminant of worldwide concern. Since the discovery of methyl mercury exposure due to eating contaminated fish as the underlying cause of the Minamata disaster, the scientific community has known about the sensitivity of the developing central nervous system to mercury toxicity. Warnings are given to pregnant women and young children to limit consumption of foods containing methyl mercury to protect the embryonic, fetal and postnatally developing central nervous system. However, evidence also suggests that exposure to methyl mercury or various forms of inorganic mercury may also affect development and function of other organs. Numerous reports indicate a worldwide increase in diabetes, particularly type 2 diabetes. Quite recently, methyl mercury has been shown to have adverse effects on pancreatic beta (β) cell development and function, resulting in insulin resistance and hyperglycemia and may even lead to the development of diabetes. This review discusses possible mechanisms by which methyl mercury exposure may adversely affect pancreatic β cell development and function, and the role that methyl mercury exposure may have in the reported worldwide increase in diabetes, particularly type 2 diabetes. While additional information is needed regarding associations between mercury exposure and specific mechanisms of the pathogenesis of diabetes in the human population, methyl mercury's adverse effects on the body's natural sources of antioxidants suggest that one possible therapeutic strategy could involve supplementation with antioxidants. Thus, it is important that additional investigation be undertaken into the role of methyl mercury exposure and reduced pancreatic β cell function. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Lauren Schumacher
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, TX, 77843-4458, USA
| | - Louise C Abbott
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, TX, 77843-4458, USA
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Fujie T, Hara T, Kaji T. Toxicology of organic-inorganic hybrid molecules: bio-organometallics and its toxicology. J Toxicol Sci 2016; 41:SP81-SP88. [PMID: 28320985 DOI: 10.2131/jts.41.sp81] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Bio-organometallics is a research strategy of biology that uses organic-inorganic hybrid molecules. The molecules are expected to exhibit useful bioactivities based on the unique structure formed by interaction between the organic structure and intramolecular metal(s). However, studies on both biology and toxicology of organic-inorganic hybrid molecules have been incompletely performed. There can be two types of toxicological studies of bio-organometallics; one is evaluation of organic-inorganic hybrid molecules and the other is analysis of biological systems from the viewpoint of toxicology using organic-inorganic hybrid molecules. Our recent studies indicate that cytotoxicity of hybrid molecules containing a metal that is nontoxic in inorganic forms can be more toxic than that of hybrid molecules containing a metal that is toxic in inorganic forms when the structure of the ligand is the same. Additionally, it was revealed that organic-inorganic hybrid molecules are useful for analysis of biological systems important for understanding the toxicity of chemical compounds including heavy metals.
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Affiliation(s)
- Tomoya Fujie
- Faculty of Pharmaceutical Sciences, Toho University
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Ge HY, Han ZJ, Tian P, Sun WJ, Xue DX, Bi Y, Yang ZH, Liu P. VEGFA Expression Is Inhibited by Arsenic Trioxide in HUVECs through the Upregulation of Ets-2 and miRNA-126. PLoS One 2015; 10:e0135795. [PMID: 26274316 PMCID: PMC4537190 DOI: 10.1371/journal.pone.0135795] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 07/27/2015] [Indexed: 12/14/2022] Open
Abstract
Arsenic trioxide (ATO) has been used to treat patients with acute promyelocytic leukemia. Recently, studies have shown that ATO can induce apoptosis in leukemic cells and blood vessel endothelial cells in a time- and dose-dependent manner through the inhibition of vascular endothelial growth factor A (VEGFA) production. VEGFA is a key factor in angiogenesis initiation. Targeted inhibition of VEGF or VEGFA expression can suppress angiogenesis; however, little is known about the mechanism by which ATO inhibits VEGFA expression. In this study, we investigated the role of miRNA-126 in the mechanism of action of ATO in human umbilical vein endothelial cells (HUVECs). ATO significantly decreased the viability and proliferation of HUVECs and decreased their migration at 48 h. Cell proliferation was inhibited by 50% (IC50) when 5.0 μmol/L ATO was used. ATO treatment induced miR-126 upregulation and HUVEC apoptosis. Transfection with a miR-126 mimic significantly downregulated VEGFA mRNA levels, and transfection with a miR-126 inhibitor significantly upregulated VEGFA mRNA levels. Finally, we showed that ATO treatment upregulated Ets-2 and miR-126 expression in HUVECs. These results demonstrate that ATO inhibits the growth of HUVECs and induces apoptosis by downregulating VEGFA. One mechanism by which this occurs is Ets-2 upregulation, which results in an increase in miR-126 levels and downregulation of VEGFA expression.
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Affiliation(s)
- Hong-yan Ge
- Key Laboratory of Harbin Medical University Eye Center, Eye Hospital, First Affiliated Hospital, Harbin Medical University, 23 Youzheng Street, Harbin, China
| | - Zhong-jing Han
- Daqing Oilfield General Hospital,9 ZhongKang street, Saertu District of Daqing, China
- Department of Biochemistry and Molecular Biology, Harbin Medical University, Harbin, China
| | - Pei Tian
- Key Laboratory of Harbin Medical University Eye Center, Eye Hospital, First Affiliated Hospital, Harbin Medical University, 23 Youzheng Street, Harbin, China
| | - Wen-jie Sun
- Key Laboratory of Harbin Medical University Eye Center, Eye Hospital, First Affiliated Hospital, Harbin Medical University, 23 Youzheng Street, Harbin, China
- Department of Cardiology, The Second Affiliated Hospital of Harbin Medical University, Key Laboratory of Myocardial Ischemia Mechanism and Treatment (Harbin Medical University), Ministry of Education, Baojian Road, Harbin, Heilongjiang Province, PR China
| | - Da-xi Xue
- Key Laboratory of Harbin Medical University Eye Center, Eye Hospital, First Affiliated Hospital, Harbin Medical University, 23 Youzheng Street, Harbin, China
| | - Yu Bi
- Key Laboratory of Harbin Medical University Eye Center, Eye Hospital, First Affiliated Hospital, Harbin Medical University, 23 Youzheng Street, Harbin, China
| | - Zhang-hui Yang
- Key Laboratory of Harbin Medical University Eye Center, Eye Hospital, First Affiliated Hospital, Harbin Medical University, 23 Youzheng Street, Harbin, China
| | - Ping Liu
- Key Laboratory of Harbin Medical University Eye Center, Eye Hospital, First Affiliated Hospital, Harbin Medical University, 23 Youzheng Street, Harbin, China
- * E-mail:
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