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Loeffler DA. Enhancing of cerebral Abeta clearance by modulation of ABC transporter expression: a review of experimental approaches. Front Aging Neurosci 2024; 16:1368200. [PMID: 38872626 PMCID: PMC11170721 DOI: 10.3389/fnagi.2024.1368200] [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: 01/10/2024] [Accepted: 05/01/2024] [Indexed: 06/15/2024] Open
Abstract
Clearance of amyloid-beta (Aβ) from the brain is impaired in both early-onset and late-onset Alzheimer's disease (AD). Mechanisms for clearing cerebral Aβ include proteolytic degradation, antibody-mediated clearance, blood brain barrier and blood cerebrospinal fluid barrier efflux, glymphatic drainage, and perivascular drainage. ATP-binding cassette (ABC) transporters are membrane efflux pumps driven by ATP hydrolysis. Their functions include maintenance of brain homeostasis by removing toxic peptides and compounds, and transport of bioactive molecules including cholesterol. Some ABC transporters contribute to lowering of cerebral Aβ. Mechanisms suggested for ABC transporter-mediated lowering of brain Aβ, in addition to exporting of Aβ across the blood brain and blood cerebrospinal fluid barriers, include apolipoprotein E lipidation, microglial activation, decreased amyloidogenic processing of amyloid precursor protein, and restricting the entrance of Aβ into the brain. The ABC transporter superfamily in humans includes 49 proteins, eight of which have been suggested to reduce cerebral Aβ levels. This review discusses experimental approaches for increasing the expression of these ABC transporters, clinical applications of these approaches, changes in the expression and/or activity of these transporters in AD and transgenic mouse models of AD, and findings in the few clinical trials which have examined the effects of these approaches in patients with AD or mild cognitive impairment. The possibility that therapeutic upregulation of ABC transporters which promote clearance of cerebral Aβ may slow the clinical progression of AD merits further consideration.
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Affiliation(s)
- David A. Loeffler
- Department of Neurology, Beaumont Research Institute, Corewell Health, Royal Oak, MI, United States
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Martella N, Colardo M, Sergio W, Petraroia M, Varone M, Pensabene D, Russo M, Di Bartolomeo S, Ranalli G, Saviano G, Segatto M. Lavender Essential Oil Modulates Hepatic Cholesterol Metabolism in HepG2 Cells. Curr Issues Mol Biol 2023; 45:364-378. [PMID: 36661512 PMCID: PMC9857966 DOI: 10.3390/cimb45010026] [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: 12/13/2022] [Revised: 12/23/2022] [Accepted: 12/28/2022] [Indexed: 01/06/2023] Open
Abstract
Cholesterol is an essential lipid that guarantees several biological processes in eukaryotic cells. Its metabolism is regulated by a complex protein network that could be significantly influenced by numerous exogenous sources, such as essential oils (EOs). For instance, it has been speculated that monoterpenoid and sesquiterpenoid compounds contained in lavender essential oil (LEO) may exert important hypocholesterolemic activities. However, the molecular mechanisms by which LEO influences cholesterol homeostasis are not characterized. In this work, we evaluated the ability of LEO to regulate the protein network that controls cholesterol metabolism in the HepG2 cell line. The main findings indicate that LEO administration increases intracellular cholesterol content. Concurrently, LEO affects the expression of proteins involved in cholesterol uptake, biosynthesis, and trafficking. These effects are partially mediated by terpinene-4-ol, one of the most abundant compounds in LEO. These results demonstrate that LEO modulates cholesterol metabolism in hepatic cells.
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Affiliation(s)
- Noemi Martella
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Mayra Colardo
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - William Sergio
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Michele Petraroia
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Michela Varone
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Daniele Pensabene
- Department of Science, University Roma Tre, Viale Marconi 446, 00146 Rome, Italy
| | - Miriam Russo
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Sabrina Di Bartolomeo
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Giancarlo Ranalli
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
| | - Gabriella Saviano
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
- Correspondence: (G.S.); (M.S.)
| | - Marco Segatto
- Department of Biosciences and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche, Italy
- Correspondence: (G.S.); (M.S.)
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3
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Martins B, Novo JP, Fonseca É, Raposo R, Sardão VA, Pereira F, Oriá RB, Fontes-Ribeiro C, Malva J. Necrotic-like BV-2 microglial cell death due to methylmercury exposure. Front Pharmacol 2022; 13:1003663. [PMID: 36408241 PMCID: PMC9667718 DOI: 10.3389/fphar.2022.1003663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 10/18/2022] [Indexed: 12/01/2022] Open
Abstract
Methylmercury (MeHg) is a dangerous environmental contaminant with strong bioaccumulation in the food chain and neurotoxic properties. In the nervous system, MeHg may cause neurodevelopment impairment and potentially interfere with immune response, compromising proper control of neuroinflammation and aggravating neurodegeneration. Human populations are exposed to environmental contamination with MeHg, especially in areas with strong mining or industrial activity, raising public health concerns. Taking this into consideration, this work aims to clarify pathways leading to acute toxic effects caused by MeHg exposure in microglial cells. BV-2 mouse microglial cells were incubated with MeHg at different concentrations (0.01, 0.1, 1 and 10 µM) for 1 h prior to continuous Lipopolysaccharide (LPS, 0.5 μg/ml) exposure for 6 or 24 h. After cell exposure, reactive oxygen species (ROS), IL-6 and TNF-α cytokines production, inducible nitric oxide synthase (iNOS) expression, nitric oxide (NO) release, metabolic activity, propidium iodide (PI) uptake, caspase-3 and -9 activities and phagocytic activity were assessed. MeHg 10 µM decreased ROS formation, the production and secretion of pro-inflammatory cytokines IL-6, TNF-α, iNOS immunoreactivity, the release of NO in BV-2 cells. Furthermore, MeHg 10 µM decreased the metabolic activity of BV-2 and increased the number of PI-positive cells (necrotic-like cell death) when compared to the respective control group. Besides, MeHg did not interfere with caspase activity or the phagocytic profile of cells. The short-term effects of a high concentration of MeHg on BV-2 microglial cells lead to impaired production of several pro-inflammatory mediators, as well as a higher microglial cell death via necrosis, compromising their neuroinflammatory response. Clarifying the mechanisms underlying MeHg-induced neurotoxicity and neurodegeneration in brain cells is relevant to better understand acute and long-term chronic neuroinflammatory responses following MeHg exposure.
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Affiliation(s)
- B. Martins
- Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal,Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
| | - J. P. Novo
- Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal,Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
| | - É. Fonseca
- Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal,Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
| | - R. Raposo
- Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal,Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal,Experimental Biology Core, Health Sciences Center, University of Fortaleza, Fortaleza, Brazil
| | - V. A. Sardão
- Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal,Center for Neuroscience and Cell Biology (CNC), UC Biotech, University of Coimbra, Cantanhede, Portugal
| | - F. Pereira
- Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal,Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
| | - R. B. Oriá
- Laboratory of Tissue Healing, Ontogeny, and Nutrition, Department of Morphology and Institute of Biomedicine, School of Medicine, Federal University of Ceará, Fortaleza, Brazil
| | - C. Fontes-Ribeiro
- Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal,Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal
| | - J. Malva
- Coimbra Institute for Clinical and Biomedical Research (iCBR), University of Coimbra, Coimbra, Portugal,Institute of Pharmacology and Experimental Therapeutics, Faculty of Medicine, University of Coimbra, Coimbra, Portugal,Center for Innovative Biomedicine and Biotechnology (CIBB), University of Coimbra, Coimbra, Portugal,*Correspondence: J. Malva,
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Brain cell type-specific cholesterol metabolism and implications for learning and memory. Trends Neurosci 2022; 45:401-414. [DOI: 10.1016/j.tins.2022.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/06/2022] [Accepted: 01/25/2022] [Indexed: 12/21/2022]
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Ho HJ, Komai M, Shirakawa H. Beneficial Effects of Vitamin K Status on Glycemic Regulation and Diabetes Mellitus: A Mini-Review. Nutrients 2020; 12:nu12082485. [PMID: 32824773 PMCID: PMC7469006 DOI: 10.3390/nu12082485] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/12/2020] [Accepted: 08/13/2020] [Indexed: 12/16/2022] Open
Abstract
Type 2 diabetes mellitus is a chronic disease that is characterized by hyperglycemia, insulin resistance, and dysfunctional insulin secretion. Glycemic control remains a crucial contributor to the progression of type 2 diabetes mellitus as well as the prevention or delay in the onset of diabetes-related complications. Vitamin K is a fat-soluble vitamin that plays an important role in the regulation of the glycemic status. Supplementation of vitamin K may reduce the risk of diabetes mellitus and improve insulin sensitivity. This mini-review summarizes the recent insights into the beneficial effects of vitamin K and its possible mechanism of action on insulin sensitivity and glycemic status, thereby suppressing the progression of diabetes mellitus.
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Affiliation(s)
- Hsin-Jung Ho
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (M.K.); (H.S.)
- Correspondence: ; Tel.: +81-11-706-3395
| | - Michio Komai
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (M.K.); (H.S.)
| | - Hitoshi Shirakawa
- Laboratory of Nutrition, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan; (M.K.); (H.S.)
- International Education and Research Center for Food Agricultural Immunology, Graduate School of Agricultural Science, Tohoku University, Sendai 980-8572, Japan
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Jeannin AC, Salem JE, Massy Z, Aubert CE, Vemeer C, Amouyal C, Phan F, Halbron M, Funck-Brentano C, Hartemann A, Bourron O. Inactive matrix gla protein plasma levels are associated with peripheral neuropathy in Type 2 diabetes. PLoS One 2020; 15:e0229145. [PMID: 32092076 PMCID: PMC7039520 DOI: 10.1371/journal.pone.0229145] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 01/30/2020] [Indexed: 02/06/2023] Open
Abstract
AIMS/HYPOTHESIS Diabetic peripheral neuropathy is a frequent and severe complication of diabetes. As Matrix-gla-protein (MGP) is expressed in several components of the nervous system and is involved in some neurological disease, MGP could play a role in peripheral nervous system homeostasis. The aim of this study was to evaluate factors associated with sensitive diabetic neuropathy in Type 2 Diabetes, and, in particular, dephospho-uncarboxylated MGP (dp-ucMGP), the inactive form of MGP. METHODS 198 patients with Type 2 Diabetes were included. Presence of sensitive diabetic neuropathy was defined by a neuropathy disability score (NDS) ≥6. Plasma levels of dp-ucMGP were measured by ELISA. RESULTS In this cohort, the mean age was 64+/-8.4 years old, and 80% of patients were men. Peripheral neuropathy was present in 15.7% of the patients and was significantly associated (r = 0.51, p<0.0001) with dp-ucMGP levels (β = -0.26, p = 0.045) after integrating effects of height (β = -0.38, p = 0.01), insulin treatment (β = 0.42, p = 0.002), retinopathy treated by laser (β = 0.26, p = 0.02), and total cholesterol levels (β = 0.3, p = 0.03) by multivariable analysis. CONCLUSIONS The association between diabetic neuropathy and the inactive form of MGP suggests the existence of new pathophysiological pathways to explore. Further studies are needed to determine if dp-ucMGP may be used as a biomarker of sensitive neuropathy. Since dp-ucMGP is a marker of poor vitamin K status, clinical studies are warranted to explore the potential protective effect of high vitamin K intake on diabetic peripheral neuropathy.
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Affiliation(s)
- Anne-Caroline Jeannin
- Sorbonne Université, Paris, France
- Assistance Publique-Hôpitaux de Paris (APHP), Diabetology Department, Pitié-Salpêtrière Hospital, Paris, France
| | - Joe-Elie Salem
- Sorbonne Université, Paris, France
- Department of Pharmacology and CIC-1421, AP-HP, Pitié-Salpêtrière Hospital, Paris, France
- INSERM, CIC-1421, Paris, France
- Institute of Cardiometabolism and Nutrition ICAN, Paris, France
| | - Ziad Massy
- Division of Nephrology, Ambroise Paré Hospital, AP-HP, Pitié-Salpêtrière Hospital, Université Paris-Saclay, Paris, France
| | - Carole Elodie Aubert
- Department of General Internal Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Institute of Primary Health Care (BIHAM), University of Bern, Bern, Switzerland
| | - Cees Vemeer
- Cardiovascular Research Institute CARIM, Maastricht University, Maastricht, The Netherlands
| | - Chloé Amouyal
- Sorbonne Université, Paris, France
- Assistance Publique-Hôpitaux de Paris (APHP), Diabetology Department, Pitié-Salpêtrière Hospital, Paris, France
- Institute of Cardiometabolism and Nutrition ICAN, Paris, France
| | - Franck Phan
- Sorbonne Université, Paris, France
- Assistance Publique-Hôpitaux de Paris (APHP), Diabetology Department, Pitié-Salpêtrière Hospital, Paris, France
- Institute of Cardiometabolism and Nutrition ICAN, Paris, France
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France
| | - Marine Halbron
- Sorbonne Université, Paris, France
- Assistance Publique-Hôpitaux de Paris (APHP), Diabetology Department, Pitié-Salpêtrière Hospital, Paris, France
- Institute of Cardiometabolism and Nutrition ICAN, Paris, France
| | - Christian Funck-Brentano
- Sorbonne Université, Paris, France
- Department of Pharmacology and CIC-1421, AP-HP, Pitié-Salpêtrière Hospital, Paris, France
- INSERM, CIC-1421, Paris, France
- Institute of Cardiometabolism and Nutrition ICAN, Paris, France
| | - Agnès Hartemann
- Sorbonne Université, Paris, France
- Assistance Publique-Hôpitaux de Paris (APHP), Diabetology Department, Pitié-Salpêtrière Hospital, Paris, France
- Institute of Cardiometabolism and Nutrition ICAN, Paris, France
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France
| | - Olivier Bourron
- Sorbonne Université, Paris, France
- Assistance Publique-Hôpitaux de Paris (APHP), Diabetology Department, Pitié-Salpêtrière Hospital, Paris, France
- Institute of Cardiometabolism and Nutrition ICAN, Paris, France
- INSERM, UMR_S 1138, Centre de Recherche des Cordeliers, Paris, France
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Tonini C, Colardo M, Colella B, Di Bartolomeo S, Berardinelli F, Caretti G, Pallottini V, Segatto M. Inhibition of Bromodomain and Extraterminal Domain (BET) Proteins by JQ1 Unravels a Novel Epigenetic Modulation to Control Lipid Homeostasis. Int J Mol Sci 2020; 21:ijms21041297. [PMID: 32075110 PMCID: PMC7072965 DOI: 10.3390/ijms21041297] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 02/08/2020] [Accepted: 02/13/2020] [Indexed: 12/19/2022] Open
Abstract
The homeostatic control of lipid metabolism is essential for many fundamental physiological processes. A deep understanding of its regulatory mechanisms is pivotal to unravel prospective physiopathological factors and to identify novel molecular targets that could be employed to design promising therapies in the management of lipid disorders. Here, we investigated the role of bromodomain and extraterminal domain (BET) proteins in the regulation of lipid metabolism. To reach this aim, we used a loss-of-function approach by treating HepG2 cells with JQ1, a powerful and selective BET inhibitor. The main results demonstrated that BET inhibition by JQ1 efficiently decreases intracellular lipid content, determining a significant modulation of proteins involved in lipid biosynthesis, uptake and intracellular trafficking. Importantly, the capability of BET inhibition to slow down cell proliferation is dependent on the modulation of cholesterol metabolism. Taken together, these data highlight a novel epigenetic mechanism involved in the regulation of lipid homeostasis.
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Affiliation(s)
- Claudia Tonini
- Department of Science, University of Rome “Roma Tre”, Viale Marconi 446, 00146 Rome, Italy; (C.T.); (F.B.); (V.P.)
| | - Mayra Colardo
- Department of Bioscience and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche (Is), Italy; (M.C.); (B.C.); (S.D.B.)
| | - Barbara Colella
- Department of Bioscience and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche (Is), Italy; (M.C.); (B.C.); (S.D.B.)
| | - Sabrina Di Bartolomeo
- Department of Bioscience and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche (Is), Italy; (M.C.); (B.C.); (S.D.B.)
| | - Francesco Berardinelli
- Department of Science, University of Rome “Roma Tre”, Viale Marconi 446, 00146 Rome, Italy; (C.T.); (F.B.); (V.P.)
| | - Giuseppina Caretti
- Department of Biosciences, University of Milan, Via Celoria 26, 20133 Milan, Italy;
| | - Valentina Pallottini
- Department of Science, University of Rome “Roma Tre”, Viale Marconi 446, 00146 Rome, Italy; (C.T.); (F.B.); (V.P.)
| | - Marco Segatto
- Department of Bioscience and Territory, University of Molise, Contrada Fonte Lappone, 86090 Pesche (Is), Italy; (M.C.); (B.C.); (S.D.B.)
- Correspondence:
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Wei FF, Trenson S, Verhamme P, Vermeer C, Staessen JA. Vitamin K-Dependent Matrix Gla Protein as Multifaceted Protector of Vascular and Tissue Integrity. Hypertension 2019; 73:1160-1169. [PMID: 31006332 PMCID: PMC6510326 DOI: 10.1161/hypertensionaha.119.12412] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Supplemental Digital Content is available in the text.
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Affiliation(s)
- Fang-Fei Wei
- From the Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences (F.-F.W., J.A.S.), University Hospitals Leuven, Belgium
| | - Sander Trenson
- Division of Cardiology (S.T.), University Hospitals Leuven, Belgium
| | - Peter Verhamme
- Centre for Molecular and Vascular Biology, Department of Cardiovascular Sciences, University of Leuven, Belgium (P.V.)
| | - Cees Vermeer
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, The Netherlands (C.V., J.A.S.)
| | - Jan A. Staessen
- From the Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences (F.-F.W., J.A.S.), University Hospitals Leuven, Belgium
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, The Netherlands (C.V., J.A.S.)
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9
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Wei FF, Huang QF, Zhang ZY, Van Keer K, Thijs L, Trenson S, Yang WY, Cauwenberghs N, Mujaj B, Kuznetsova T, Allegaert K, Struijker-Boudier HAJ, Verhamme P, Vermeer C, Staessen JA. Inactive matrix Gla protein is a novel circulating biomarker predicting retinal arteriolar narrowing in humans. Sci Rep 2018; 8:15088. [PMID: 30305657 PMCID: PMC6180139 DOI: 10.1038/s41598-018-33257-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 09/17/2018] [Indexed: 12/15/2022] Open
Abstract
Active matrix Gla protein (MGP), a potent inhibitor of calcification in large arteries, protects against macrovascular complications. Recent studies suggested that active MGP helps maintaining the integrity of the renal and myocardial microcirculation, but its role in preserving the retinal microcirculation remains unknown. In 935 randomly recruited Flemish participants (mean age, 40.9 years; 50.3% women), we measured plasma desphospho-uncarboxylated MGP (dp-ucMGP), a marker of poor vitamin K status using an ELISA-based assay at baseline (1996-2010) and retinal microvascular diameters using IVAN software (Vasculomatic ala Nicola, version 1.1) including the central retinal arteriolar (CRAE) and venular (CRVE) equivalent and the arteriole-to-venule ratio (AVR) at follow-up (2008-2015). CRAE (P = 0.005) and AVR (P = 0.080) at follow-up decreased across tertiles of the dp-ucMGP distribution. In unadjusted models, for a doubling of dp-ucMGP at baseline, CRAE and AVR at follow-up respectively decreased by 1.40 µm (95% confidence interval [CI], 0.32 to 2.48; P = 0.011) and 0.006 (CI, 0.001 to 0.011; P = 0.016). In multivariable-adjusted models accounting for sex, baseline characteristics and follow-up duration, these estimates were -1.03 µm (CI, -1.96 to -0.11; P = 0.028) and -0.007 (CI, -0.011 to -0.002; P = 0.007). Additional adjustment for changes from baseline to follow-up in major baseline characteristics yielded as estimates -0.91 µm (CI, -1.82 to -0.01; P = 0.048) and -0.006 (95% CI, -0.011 to -0.001; P = 0.014), respectively. Circulating inactive dp-ucMGP is a long-term predictor of smaller retinal arteriolar diameter in the general population. Our observations highlight the possibility that vitamin K supplementation might promote retinal health.
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Affiliation(s)
- Fang-Fei Wei
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Qi-Fang Huang
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Zhen-Yu Zhang
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Karel Van Keer
- Department of Ophthalmology, University Hospitals Leuven, Leuven, Belgium
| | - Lutgarde Thijs
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Sander Trenson
- Division of Cardiology, University Hospitals Leuven, Leuven, Belgium
| | - Wen-Yi Yang
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Nicholas Cauwenberghs
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Blerim Mujaj
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Tatiana Kuznetsova
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Karel Allegaert
- Research Unit Organ Systems, Department of Development and Regeneration, University of Leuven, Leuven, Belgium
- Department of Pediatric Surgery and Intensive Care and Neonatology, Erasmus Medical Centre, Sophia Children's Hospital, Rotterdam, The Netherlands
| | | | - Peter Verhamme
- Centre for Molecular and Vascular Biology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Cees Vermeer
- R&D Group VitaK, Maastricht University, Maastricht, The Netherlands
| | - Jan A Staessen
- Studies Coordinating Centre, Research Unit Hypertension and Cardiovascular Epidemiology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium.
- Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, The Netherlands.
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Bollaerts I, Veys L, Geeraerts E, Andries L, De Groef L, Buyens T, Salinas-Navarro M, Moons L, Van Hove I. Complementary research models and methods to study axonal regeneration in the vertebrate retinofugal system. Brain Struct Funct 2017; 223:545-567. [DOI: 10.1007/s00429-017-1571-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 11/15/2017] [Indexed: 01/18/2023]
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11
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van Deijk ALF, Camargo N, Timmerman J, Heistek T, Brouwers JF, Mogavero F, Mansvelder HD, Smit AB, Verheijen MHG. Astrocyte lipid metabolism is critical for synapse development and function in vivo. Glia 2017; 65:670-682. [PMID: 28168742 DOI: 10.1002/glia.23120] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 01/08/2017] [Accepted: 01/10/2017] [Indexed: 12/21/2022]
Abstract
The brain is considered to be autonomous in lipid synthesis with astrocytes producing lipids far more efficiently than neurons. Accordingly, it is generally assumed that astrocyte-derived lipids are taken up by neurons to support synapse formation and function. Initial confirmation of this assumption has been obtained in cell cultures, but whether astrocyte-derived lipids support synapses in vivo is not known. Here, we address this issue and determined the role of astrocyte lipid metabolism in hippocampal synapse formation and function in vivo. Hippocampal protein expression for the sterol regulatory element-binding protein (SREBP) and its target gene fatty acid synthase (Fasn) was found in astrocytes but not in neurons. Diminishing SREBP activity in astrocytes using mice in which the SREBP cleavage-activating protein (SCAP) was deleted from GFAP-expressing cells resulted in decreased cholesterol and phospholipid secretion by astrocytes. Interestingly, SCAP mutant mice showed more immature synapses, lower presynaptic protein SNAP-25 levels as well as reduced numbers of synaptic vesicles, indicating impaired development of the presynaptic terminal. Accordingly, hippocampal short-term and long-term synaptic plasticity were defective in mutant mice. These findings establish a critical role for astrocyte lipid metabolism in presynaptic terminal development and function in vivo. GLIA 2017;65:670-682.
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Affiliation(s)
- Anne-Lieke F van Deijk
- Department of Molecular & Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
| | - Nutabi Camargo
- Department of Molecular & Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
| | - Jaap Timmerman
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
| | - Tim Heistek
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
| | - Jos F Brouwers
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Yalelaan 1, 3584 CL Utrecht University, Utrecht, The Netherlands
| | - Floriana Mogavero
- Department of Molecular & Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
| | - Huibert D Mansvelder
- Department of Integrative Neurophysiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
| | - August B Smit
- Department of Molecular & Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
| | - Mark H G Verheijen
- Department of Molecular & Cellular Neurobiology, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam, De Boelelaan 1085, Amsterdam, 1081 HV, The Netherlands
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13
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Valenza M, Marullo M, Di Paolo E, Cesana E, Zuccato C, Biella G, Cattaneo E. Disruption of astrocyte-neuron cholesterol cross talk affects neuronal function in Huntington's disease. Cell Death Differ 2014; 22:690-702. [PMID: 25301063 DOI: 10.1038/cdd.2014.162] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Revised: 08/13/2014] [Accepted: 09/03/2014] [Indexed: 01/22/2023] Open
Abstract
In the adult brain, neurons require local cholesterol production, which is supplied by astrocytes through apoE-containing lipoproteins. In Huntington's disease (HD), such cholesterol biosynthesis in the brain is severely reduced. Here we show that this defect, occurring in astrocytes, is detrimental for HD neurons. Astrocytes bearing the huntingtin protein containing increasing CAG repeats secreted less apoE-lipoprotein-bound cholesterol in the medium. Conditioned media from HD astrocytes and lipoprotein-depleted conditioned media from wild-type (wt) astrocytes were equally detrimental in a neurite outgrowth assay and did not support synaptic activity in HD neurons, compared with conditions of cholesterol supplementation or conditioned media from wt astrocytes. Molecular perturbation of cholesterol biosynthesis and efflux in astrocytes caused similarly altered astrocyte-neuron cross talk, whereas enhancement of glial SREBP2 and ABCA1 function reversed the aspects of neuronal dysfunction in HD. These findings indicate that astrocyte-mediated cholesterol homeostasis could be a potential therapeutic target to ameliorate neuronal dysfunction in HD.
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Affiliation(s)
- M Valenza
- Department of Biosciences and Centre for Stem Cell Research, Università degli Studi di Milano, Milano, Italy
| | - M Marullo
- Department of Biosciences and Centre for Stem Cell Research, Università degli Studi di Milano, Milano, Italy
| | - E Di Paolo
- Department of Biosciences and Centre for Stem Cell Research, Università degli Studi di Milano, Milano, Italy
| | - E Cesana
- Department of Biology and Biotechnology, Università degli Studi di Pavia, Pavia, Italy
| | - C Zuccato
- Department of Biosciences and Centre for Stem Cell Research, Università degli Studi di Milano, Milano, Italy
| | - G Biella
- Department of Biology and Biotechnology, Università degli Studi di Pavia, Pavia, Italy
| | - E Cattaneo
- Department of Biosciences and Centre for Stem Cell Research, Università degli Studi di Milano, Milano, Italy
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Suga A, Sadamoto K, Fujii M, Mandai M, Takahashi M. Proliferation potential of Müller glia after retinal damage varies between mouse strains. PLoS One 2014; 9:e94556. [PMID: 24747725 PMCID: PMC3991641 DOI: 10.1371/journal.pone.0094556] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 03/18/2014] [Indexed: 01/12/2023] Open
Abstract
Retinal Müller glia can serve as a source for regeneration of damaged retinal neurons in fish, birds and mammals. However, the proliferation rate of Müller glia has been reported to be low in the mammalian retina. To overcome this problem, growth factors and morphogens have been studied as potent promoters of Müller glial proliferation, but the molecular mechanisms that limit the proliferation of Müller glia in the mammalian retina remain unknown. In the present study, we found that the degree of damage-induced Müller glia proliferation varies across mouse strains. In mouse line 129×1/SvJ (129), there was a significantly larger proliferative response compared with that observed in C57BL/6 (B6) after photoreceptor cell death. Treatment with a Glycogen synthase kinase 3 (GSK3) inhibitor enhanced the proliferation of Müller glia in 129 but not in B6 mouse retinas. We therefore focused on the different gene expression patterns during retinal degeneration between B6 and 129. Expression levels of Cyclin D1 and Nestin correlated with the degree of Müller glial proliferation. A comparison of genome-wide gene expression between B6 and 129 showed that distinct sets of genes were upregulated in the retinas after damage, including immune response genes and chromatin remodeling factors.
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Affiliation(s)
- Akiko Suga
- Laboratory for Retinal Regeneration, Center for Developmental Biology, RIKEN, Minatojima, Chu-O-ku, Kobe, Japan
| | - Kazuyo Sadamoto
- Laboratory for Retinal Regeneration, Center for Developmental Biology, RIKEN, Minatojima, Chu-O-ku, Kobe, Japan
| | - Momo Fujii
- Laboratory for Retinal Regeneration, Center for Developmental Biology, RIKEN, Minatojima, Chu-O-ku, Kobe, Japan
| | - Michiko Mandai
- Laboratory for Retinal Regeneration, Center for Developmental Biology, RIKEN, Minatojima, Chu-O-ku, Kobe, Japan
| | - Masayo Takahashi
- Laboratory for Retinal Regeneration, Center for Developmental Biology, RIKEN, Minatojima, Chu-O-ku, Kobe, Japan
- * E-mail:
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15
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Boraldi F, Annovi G, Vermeer C, Schurgers LJ, Trenti T, Tiozzo R, Guerra D, Quaglino D. Matrix gla protein and alkaline phosphatase are differently modulated in human dermal fibroblasts from PXE patients and controls. J Invest Dermatol 2013; 133:946-54. [PMID: 23223140 DOI: 10.1038/jid.2012.460] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mineralization of elastic fibers in pseudoxanthoma elasticum (PXE) has been associated with low levels of carboxylated matrix gla protein (MGP), most likely as a consequence of reduced vitamin K (vit K) availability. Unexpectedly, vit K supplementation does not exert beneficial effects on soft connective tissue mineralization in the PXE animal model. To understand the effects of vit K supplementation and in the attempt to interfere with pathways leading to the accumulation of calcium and phosphate within PXE-mineralized soft connective tissues, we have conducted in vitro studies on dermal fibroblasts isolated from control subjects and from PXE patients. Cells were cultured in standard conditions and in calcifying medium (CM) in the presence of vit K1 and K2, or levamisole, an alkaline phosphatase (ALP) inhibitor. Control and PXE fibroblasts were characterized by a similar dose-dependent uptake of both vit K1 and vit K2, thus promoting a significant increase of total protein carboxylation in all cell lines. Nevertheless, MGP carboxylation remained much less in PXE fibroblasts. Interestingly, PXE fibroblasts exhibited a significantly higher ALP activity. Consistently, the mineralization process induced in vitro by a long-term culture in CM appeared unaffected by vit K, whereas it was abolished by levamisole.
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Affiliation(s)
- Federica Boraldi
- Department of Life Sciences, University of Modena and Reggio Emilia, Modena, Italy
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16
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Wu WJ, Ahn BY. Improved menaquinone (Vitamin K2) production in cheonggukjang by optimization of the fermentation conditions. Food Sci Biotechnol 2011. [DOI: 10.1007/s10068-011-0219-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022] Open
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17
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Jennemann R, Rabionet M, Gorgas K, Epstein S, Dalpke A, Rothermel U, Bayerle A, van der Hoeven F, Imgrund S, Kirsch J, Nickel W, Willecke K, Riezman H, Gröne HJ, Sandhoff R. Loss of ceramide synthase 3 causes lethal skin barrier disruption. Hum Mol Genet 2011; 21:586-608. [PMID: 22038835 DOI: 10.1093/hmg/ddr494] [Citation(s) in RCA: 218] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The stratum corneum as the outermost epidermal layer protects against exsiccation and infection. Both the underlying cornified envelope (CE) and the intercellular lipid matrix contribute essentially to these two main protective barriers. Epidermis-unique ceramides with ultra-long-chain acyl moities (ULC-Cers) are key components of extracellular lipid lamellae (ELL) and are bound to CE proteins, thereby contributing to the cornified lipid envelope (CLE). Here, we identified human and mouse ceramide synthase 3 (CerS3), among CerS1-6, to be exclusively required for the ULC-Cer synthesis in vitro and of mouse CerS3 in vivo. Deficiency of CerS3 in mice results in complete loss of ULC-Cers (≥C26), lack of continuous ELL and a non-functional CLE. Consequently, newborn mutant mice die shortly after birth from transepidermal water loss. Mutant skin is prone to Candida albicans infection highlighting ULC-Cers to be pivotal for both barrier functions. Persistent periderm, hyperkeratosis and deficient cornification are hallmarks of mutant skin demonstrating loss of Cers to trigger a keratinocyte maturation arrest at an embryonic pre-barrier stage.
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Affiliation(s)
- Richard Jennemann
- Cellular & Molecular Pathology, German Cancer Research Center, 69120 Heidelberg, Germany
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18
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Ni M, Li X, Yin Z, Sidoryk-Węgrzynowicz M, Jiang H, Farina M, Rocha JBT, Syversen T, Aschner M. Comparative study on the response of rat primary astrocytes and microglia to methylmercury toxicity. Glia 2011; 59:810-20. [PMID: 21351162 DOI: 10.1002/glia.21153] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Accepted: 01/11/2011] [Indexed: 12/16/2022]
Abstract
As the two major glial cell types in the brain, astrocytes and microglia play pivotal but different roles in maintaining optimal brain function. Although both cell types have been implicated as major targets of methylmercury (MeHg), their sensitivities and adaptive responses to this metal can vary given their distinctive properties and physiological functions. This study was carried out to compare the responses of astrocytes and microglia following MeHg treatment, specifically addressing the effects of MeHg on cell viability, reactive oxygen species (ROS) generation and glutathione (GSH) levels, as well as mercury (Hg) uptake and the expression of NF-E2-related factor 2 (Nrf2). Results showed that microglia are more sensitive to MeHg than astrocytes, a finding that is consistent with their higher Hg uptake and lower basal GSH levels. Microglia also demonstrated higher ROS generation compared with astrocytes. Nrf2 and its downstream genes were upregulated in both cell types, but with different kinetics (much faster in microglia). In summary, microglia and astrocytes each exhibit a distinct sensitivity to MeHg, resulting in their differential temporal adaptive responses. These unique sensitivities appear to be dependent on the cellular thiol status of the particular cell type.
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Affiliation(s)
- Mingwei Ni
- Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA
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Markiewicz I, Sypecka J, Domanska-Janik K, Wyszomirski T, Lukomska B. Cellular environment directs differentiation of human umbilical cord blood-derived neural stem cells in vitro. J Histochem Cytochem 2011; 59:289-301. [PMID: 21378283 DOI: 10.1369/0022155410397997] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cord blood-derived neural stem cells (NSCs) are proposed as an alternative cell source to repair brain damage upon transplantation. However, there is a lack of data showing how these cells are driven to generate desired phenotypes by recipient nervous tissue. Previous research indicates that local environment provides signals driving the fate of stem cells. To investigate the impact of these local cues interaction, the authors used a model of cord blood-derived NSCs co-cultured with different rat brain-specific primary cultures, creating the neural-like microenvironment conditions in vitro. Neuronal and astro-, oligo-, and microglia cell cultures were obtained by the previously described methods. The CMFDA-labeled neural stem cells originated from, non-transformed human umbilical cord blood cell line (HUCB-NSCs) established in a laboratory. The authors show that the close vicinity of astrocytes and oligodendrocytes promotes neuronal differentiation of HUCB-NSCs, whereas postmitotic neurons induce oligodendrogliogenesis of these cells. In turn, microglia or endothelial cells do not favor any phenotypes of their neural commitment. Studies have confirmed that HUCB-NSCs can read cues from the neurogenic microenvironment, attaining features of neurons, astrocytes, or oligodendrocytes. The specific responses of neurally committed cord blood-derived cells, reported in this work, are very much similar to those described previously for NSCs derived from other "more typical" sources. This further proves their genuine neural nature. Apart from having a better insight into the neurogenesis in the adult brain, these findings might be important when predicting cord blood cell derivative behavior after their transplantation for neurological disorders.
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Affiliation(s)
- Inga Markiewicz
- Neurorepair Department, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
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Buard I, Steinmetz CC, Claudepierre T, Pfrieger FW. Glial cells promote dendrite formation and the reception of synaptic input in Purkinje cells from postnatal mice. Glia 2010; 58:538-45. [PMID: 19908290 DOI: 10.1002/glia.20943] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Previous studies suggest that glial cells contribute to synaptogenesis in specific neurons from the postnatal CNS. Here, we studied whether this is true for Purkinje cells (PCs), which represent a unique neuronal cell type due to their large size, massive synaptic input, and high vulnerability. Using new glia-free cultures enriched in PCs from postnatal mice we show that these neurons survived and grew, but displayed only low levels of excitatory and inhibitory synaptic activity. Coculture with glial cells strongly enhanced the frequency and size of spontaneous and miniature excitatory synaptic currents as well as neurite growth and branching. Immunocytochemical staining for microtubule-associated protein 2- (MAP2-) positive neurites revealed impaired dendrite formation in PCs under glia-free conditions, which can explain the absence of synaptic activity. Glial signals strongly enhanced dendritogenesis in PCs and thus their ability to receive excitatory synaptic input from granule cells (GCs). The enhancement of dendrite formation was mimicked by glia-conditioned medium (GCM), whereas the increase in synaptic activity required physical presence of glia. This indicated that dendrite development is necessary but not sufficient for PCs to receive excitatory synaptic input and that synaptogenesis requires additional signals. The level of inhibitory synaptic activity was low even in cocultures due to a low incidence of inhibitory interneurons. Taken together, our results reinforce the idea that glial cells promote synaptogenesis in specific neuronal cell types.
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Affiliation(s)
- Isabelle Buard
- CNRS UPR 3212, University of Strasbourg, Institute for Cellular and Integrative Neurosciences (INCI), 5, rue Blaise Pascal, F-67084 Strasbourg Cedex, France
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Rochman M, Malicet C, Bustin M. HMGN5/NSBP1: a new member of the HMGN protein family that affects chromatin structure and function. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2010; 1799:86-92. [PMID: 20123071 DOI: 10.1016/j.bbagrm.2009.09.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2009] [Revised: 09/15/2009] [Accepted: 09/15/2009] [Indexed: 12/22/2022]
Abstract
The dynamic nature of the chromatin fiber provides the structural and functional flexibility required for the accurate transcriptional responses to various stimuli. In living cells, structural proteins such as the linker histone H1 and the high mobility group (HMG) proteins continuously modulate the local and global architecture of the chromatin fiber and affect the binding of regulatory factors to their nucleosomal targets. HMGN proteins specifically bind to the nucleosome core particle through a highly conserved "nucleosomal binding domain" (NBD) and reduce chromatin compaction. HMGN5 (NSBP1), a new member of the HMGN protein family, is ubiquitously expressed in mouse and human tissues. Similar to other HMGNs, HMGN5 is a nuclear protein which binds to nucleosomes via NBD, unfolds chromatin, and affects transcription. This protein remains mainly uncharacterized and its biological function is unknown. In this review, we describe the structure of the HMGN5 gene and the known properties of the HMGN5 protein. We present recent findings related to the expression pattern of the protein during development, the mechanism of HMGN5 action on chromatin, and discuss the possible role of HMGN5 in pathological and physiological processes.
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Affiliation(s)
- Mark Rochman
- Protein Section, Laboratory of Metabolism, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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22
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Schengrund CL. Lipid rafts: Keys to neurodegeneration. Brain Res Bull 2010; 82:7-17. [DOI: 10.1016/j.brainresbull.2010.02.013] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 02/16/2010] [Accepted: 02/23/2010] [Indexed: 01/11/2023]
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Role of glial cells in the formation and maintenance of synapses. ACTA ACUST UNITED AC 2009; 63:39-46. [PMID: 19931561 DOI: 10.1016/j.brainresrev.2009.11.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2009] [Revised: 11/06/2009] [Accepted: 11/11/2009] [Indexed: 11/23/2022]
Abstract
Synaptogenesis is a decisive process for the development of the brain, its plasticity during adulthood and its regeneration after injury and disease. Despite tremendous progress during the last decades, it remains unclear, whether neurons can form synapses autonomously. In this review, I will summarize recent evidence that this is probably not the case and that distinct phases of synapse development depend on help from glial cells. The results supporting this view come from studies on the central and peripheral nervous system and on different experimental models including cultured cells as well as living flies, worms and mice. Our understanding of synapse-glia interactions in the developing, adult and diseased brain is likely to advance more rapidly as new experimental approaches to identify, visualize and manipulate glial cells in vivo become available.
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Differential gene expression analysis of human entorhinal cortex support a possible role of some extracellular matrix proteins in the onset of Alzheimer disease. Neurosci Lett 2009; 468:225-8. [PMID: 19922771 DOI: 10.1016/j.neulet.2009.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Revised: 10/23/2009] [Accepted: 11/02/2009] [Indexed: 01/19/2023]
Abstract
The onset of Alzheimer's disease (AD) has been associated with the specific vulnerability of neurons in the upper layers of the entorhinal cortex. To define the molecular characteristics of those neurons, we have used microarrays to define the gene expression in that region. In this way, we identified several genes that are expressed distinctly in the upper and lower layers of the entorhinal cortex. These include the genes encoding the matrix Gla protein, collagen type 1alpha2, reelin, semaphorin 3C or the relaxin receptor, all related to the extracellular matrix. Thus, differences in the extracellular matrix components between the upper and lower layers of the entorhinal cortex may in part explain the vulnerability of neurons present in the upper layers of this brain region in disorders like AD.
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Mertsch S, Schurgers LJ, Weber K, Paulus W, Senner V. Matrix gla protein (MGP): an overexpressed and migration-promoting mesenchymal component in glioblastoma. BMC Cancer 2009; 9:302. [PMID: 19712474 PMCID: PMC2739228 DOI: 10.1186/1471-2407-9-302] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 08/27/2009] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Recent studies have demonstrated that a molecular subtype of glioblastoma is characterized by overexpression of extracellular matrix (ECM)/mesenchymal components and shorter survival. Specifically, gene expression profiling studies revealed that matrix gla protein (MGP), whose function has traditionally been linked to inhibition of calcification of arteries and cartilage, is overexpressed in glioblastomas and associated with worse outcome. METHODS In order to analyze the role of MGP in glioblastomas, we performed expression, migration and proliferation studies. RESULTS Real-time PCR and ELISA assays confirmed overexpression of MGP in glioblastoma biopsy specimens and cell lines at mRNA and protein levels as compared to normal brain tissue. Immunohistochemistry verified positivity of glial tumor cells for MGP. RNAi-mediated knockdown of MGP in three glioma cell lines (U343MG, U373MG, H4) led to marked reduction of migration, as demonstrated by wound healing and transwell assays, while no effect on proliferation was seen. CONCLUSION Our data suggest that upregulation of MGP (and possibly other ECM-related components as well) results in unfavorable prognosis via increased migration.
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Affiliation(s)
- Sonja Mertsch
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - Leon J Schurgers
- VitaK Inc. and Cardiovascular Research Institute CARIM, Maastricht, the Netherlands
| | - Kathrin Weber
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - Werner Paulus
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
| | - Volker Senner
- Institute of Neuropathology, University Hospital Münster, Münster, Germany
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Sypecka J, Sarnowska A, Domanska-Janik K. Crucial role of the local micro-environment in fate decision of neonatal rat NG2 progenitors. Cell Prolif 2009; 42:661-71. [PMID: 19614677 DOI: 10.1111/j.1365-2184.2009.00618.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVES The fate choice of neural progenitor cells could be dictated by local cellular environment of the adult CNS. The aim of our study was to investigate the effect of hippocampal tissue on differentiation and maturation of oligodendrocyte NG2 precursor cells. MATERIALS AND METHODS Hippocampal slice culture was established from the brains of 7-day-old rats. NG2 precursor cells, obtained from a 12-day-old mixed primary culture of neonatal rat cerebral hemispheres, were labelled with chloromethyl-fluorescein-diacetete and seeded on the hippocampal slices. After 7-14 days in co-culture, cells were stained with neural markers. RESULTS NG2 cells differentiated predominantly into oligodendrocytes, presenting various stages of maturation: progenitors (NG2), pre-oligodendrocytes (O4) and finally mature GalC-positive cells. However, except for a few cells with astrocyte-specific S100b staining, a considerable number of these cells differentiated into neurons: TUJ(+) and even MAP-2(+) cells were frequently observed. Moreover, a certain population of these cells preserved proliferative properties of primary precursor cells, as revealed by Ki67 expression. CONCLUSIONS The neuronal micro-environment provided by the culture of hippocampal slices is potent for induction of neurogenesis from oligodendrocyte NG2(+)/PDGFRalpha(+)/CNP(+) progenitor cells and promotes their differentiation not only into macroglia but also into neurons. It also sustains their proliferative capacity. The results indicate the crucial role of the local cellular environment in fate decision of primary NG2(+) multipotent neural progenitor cells, which may affect their behaviour after transplantation into the central nervous system.
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Affiliation(s)
- J Sypecka
- NeuroRepair Department, Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland.
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27
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Pfrieger FW. Roles of glial cells in synapse development. Cell Mol Life Sci 2009; 66:2037-47. [PMID: 19308323 PMCID: PMC2705714 DOI: 10.1007/s00018-009-0005-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2008] [Revised: 01/20/2009] [Accepted: 02/10/2009] [Indexed: 11/29/2022]
Abstract
Brain function relies on communication among neurons via highly specialized contacts, the synapses, and synaptic dysfunction lies at the heart of age-, disease-, and injury-induced defects of the nervous system. For these reasons, the formation-and repair-of synaptic connections is a major focus of neuroscience research. In this review, I summarize recent evidence that synapse development is not a cell-autonomous process and that its distinct phases depend on assistance from the so-called glial cells. The results supporting this view concern synapses in the central nervous system as well as neuromuscular junctions and originate from experimental models ranging from cell cultures to living flies, worms, and mice. Peeking at the future, I will highlight recent technical advances that are likely to revolutionize our views on synapse-glia interactions in the developing, adult and diseased brain.
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Affiliation(s)
- Frank W Pfrieger
- Institute of Cellular and Integrative Neurosciences, CNRS UPR-3212, University of Strasbourg, 5, rue Louis Pasteur, 67084, Strasbourg, France.
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28
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Nieweg K, Schaller H, Pfrieger FW. Marked differences in cholesterol synthesis between neurons and glial cells from postnatal rats. J Neurochem 2009; 109:125-34. [DOI: 10.1111/j.1471-4159.2009.05917.x] [Citation(s) in RCA: 168] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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29
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Whitfield JF. The road to LOAD: late-onset Alzheimer's disease and a possible way to block it. Expert Opin Ther Targets 2007; 11:1257-60. [PMID: 17907956 DOI: 10.1517/14728222.11.10.1257] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The ageing brain becomes increasingly less able to destroy or eject toxic amyloid (A) beta42 peptide byproducts of normal neuronal activity that consequently accumulate to induce Alzheimer's disease (AD). Therefore, the various components of the Abeta-clearing machinery are prime targets for AD therapeutics. In this connection, there are reports that taking statins to lower circulating cholesterol to prevent cardiovascular disease can also prevent late-onset AD (LOAD) the most common form of the disease. However, it seems unlikely that statins would prevent LOAD by lowering the very long-lived brain cholesterol that is controlled independently from the very much shorter-lived circulating cholesterol. In fact, reducing the ability of the brain astrocytes to make cholesterol for their closely associated neuron clients' synaptogenesis could damage the brain rather than protect it. However, a plausible way statins might prevent LOAD is to target a main component of the clearance machinery, low-density lipoprotein receptor-related protein 1 (LRP1), the brain's powerful Abeta-efflux driver. This is indicated by a reported ability of micromolar concentrations of lovastatin and simvastatin to strongly stimulate brain vascular endothelial cells to make this Abeta ejector. Therefore, if this holds up, taking a statin over the years would prevent the normal decline of LRP1 in the ageing brain and a LOAD-driving accumulation of Abeta.
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