1
|
Woulfe J, Munoz DG, Gray DA, Jinnah HA, Ivanova A. Inosine monophosphate dehydrogenase intranuclear inclusions are markers of aging and neuronal stress in the human substantia nigra. Neurobiol Aging 2024; 134:43-56. [PMID: 37992544 DOI: 10.1016/j.neurobiolaging.2023.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 11/03/2023] [Accepted: 11/06/2023] [Indexed: 11/24/2023]
Abstract
We explored mechanisms involved in the age-dependent degeneration of human substantia nigra (SN) dopamine (DA) neurons. Owing to its important metabolic functions in post-mitotic neurons, we investigated the developmental and age-associated changes in the purine biosynthetic enzyme inosine monophosphate dehydrogenase (IMPDH). Tissue microarrays prepared from post-mortem samples of SN from 85 neurologically intact participants humans spanning the age spectrum were immunostained for IMPDH combined with other proteins. SN DA neurons contained two types of IMPDH structures: cytoplasmic IMPDH filaments and intranuclear IMPDH inclusions. The former were not age-restricted and may represent functional units involved in sustaining purine nucleotide supply in these highly metabolically active cells. The latter showed age-associated changes, including crystallization, features reminiscent of pathological inclusion bodies, and spatial associations with Marinesco bodies; structures previously associated with SN neuron dysfunction and death. We postulate dichotomous roles for these two subcellularly distinct IMPDH structures and propose a nucleus-based model for a novel mechanism of SN senescence that is independent of previously known neurodegeneration-associated proteins.
Collapse
Affiliation(s)
- John Woulfe
- Neuroscience Program, The Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, Canada.
| | - David G Munoz
- Li Ka Shing Knowledge Institute & Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada; Department of Laboratory Medicine, St. Michael's Hospital, Unity Health, University of Toronto, Toronto, Ontario, Canada
| | - Douglas A Gray
- Center for Cancer Therapeutics, The Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Hyder A Jinnah
- Departments of Neurology, Human Genetics & Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Alyona Ivanova
- The Arthur and Sonia Labatt Brain Tumor Research Center, The Hospital for Sick Children and Neurosurgery Research Department, St. Michael's Hospital, Toronto Unity Health, Toronto, Ontario, Canada
| |
Collapse
|
2
|
Wang M, Sun P, Li Z, Li J, Lv X, Chen S, Zhu X, Chai X, Zhao S. Eucommiae cortex polysaccharides attenuate gut microbiota dysbiosis and neuroinflammation in mice exposed to chronic unpredictable mild stress: Beneficial in ameliorating depressive-like behaviors. J Affect Disord 2023; 334:278-292. [PMID: 37156274 DOI: 10.1016/j.jad.2023.04.117] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 04/13/2023] [Accepted: 04/29/2023] [Indexed: 05/10/2023]
Abstract
BACKGROUND Chronic stress alters gut microbiota composition, as well as induces inflammatory responses and behavioral deficits. Eucommiae cortex polysaccharides (EPs) have been reported to remodel gut microbiota and ameliorate obesogenic diet-induced systemic low-grade inflammation, but their role in stress-induced behavioral and physiological changes is poorly understood. METHODS Male Institute of Cancer Research (ICR) mice were exposed to chronic unpredictable stress (CUMS) for 4 weeks and then supplemented with EPs at a dose of 400 mg/kg once per day for 2 weeks. Behavioral test-specific antidepressant and anxiolytic effects of EPs were assessed in FST, TST, EPM, and OFT. Microbiota composition and inflammation were detected using 16S ribosomal RNA (rRNA) gene sequencing, quantitative RT-PCR, western blot, and immunofluorescence. RESULTS We found that EPs ameliorated gut dysbiosis caused by CUMS, as evidenced by increasing the abundance of Lactobacillaceae and suppressing the expansion of the Proteobacteria, thereby mitigating intestinal inflammation and barrier derangement. Importantly, EPs reduced the release of bacterial-derived lipopolysaccharides (LPS, endotoxin) and inhibited the microglia-mediated TLR4/NFκB/MAPK signaling pathway, thereby attenuating the pro-inflammatory response in the hippocampus. These contributed to restoring the rhythm of hippocampal neurogenesis and alleviating behavioral abnormalities in CUMS mice. Correlation analysis showed that the perturbed-gut microbiota was strongly correlated with behavioral abnormalities and neuroinflammation. LIMITATIONS This study did not clarify the causal relationship between EPs remodeling the gut microbiota and improved behavior in CUMS mice. CONCLUSIONS EPs exert ameliorative effects on CUMS-induced neuroinflammation and depression-like symptoms, which may be strongly related to their beneficial effects on gut microbial composition.
Collapse
Affiliation(s)
- Mengli Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Penghao Sun
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Zhuoni Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Jing Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Xin Lv
- College of Food Science and Engineering, Northwest A&F University, Yangling, China
| | - Shulin Chen
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Xiaoyan Zhu
- College of Veterinary Medicine, Northwest A&F University, Yangling, China.
| | - Xuejun Chai
- College of Basic Medicine, Xi'an Medical University, Xi'an, China.
| | - Shanting Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling, China.
| |
Collapse
|
3
|
Smeele PH, Vaccari T. Snapshots from within the cell: Novel trafficking and non trafficking functions of Snap29 during tissue morphogenesis. Semin Cell Dev Biol 2023; 133:42-52. [PMID: 35256275 DOI: 10.1016/j.semcdb.2022.02.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 02/17/2022] [Accepted: 02/24/2022] [Indexed: 01/27/2023]
Abstract
Membrane trafficking is a core cellular process that supports diversification of cell shapes and behaviors relevant to morphogenesis during development and in adult organisms. However, how precisely trafficking components regulate specific differentiation programs is incompletely understood. Snap29 is a multifaceted Soluble N-ethylmaleimide-sensitive factor Attachment protein Receptor, involved in a wide range of trafficking and non-trafficking processes in most cells. A body of knowledge, accrued over more than two decades since its discovery, reveals that Snap29 is essential for establishing and maintaining the operation of a number of cellular events that support cell polarity and signaling. In this review, we first summarize established functions of Snap29 and then we focus on novel ones in the context of autophagy, Golgi trafficking and vesicle fusion at the plasma membrane, as well as on non-trafficking activities of Snap29. We further describe emerging evidence regarding the compartmentalisation and regulation of Snap29. Finally, we explore how the loss of distinct functions of human Snap29 may lead to the clinical manifestations of congenital disorders such as CEDNIK syndrome and how altered SNAP29 activity may contribute to the pathogenesis of cancer, viral infection and neurodegenerative diseases.
Collapse
Affiliation(s)
- Paulien H Smeele
- Department of Biosciences, Università Degli Studi Di Milano, Milan, Italy
| | - Thomas Vaccari
- Department of Biosciences, Università Degli Studi Di Milano, Milan, Italy.
| |
Collapse
|
4
|
Thangadurai S, Bajgiran M, Manickam S, Mohana-Kumaran N, Azzam G. CTP synthase: the hissing of the cellular serpent. Histochem Cell Biol 2022; 158:517-534. [PMID: 35881195 PMCID: PMC9314535 DOI: 10.1007/s00418-022-02133-w] [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] [Accepted: 06/26/2022] [Indexed: 12/24/2022]
Abstract
CTP biosynthesis is carried out by two pathways: salvage and de novo. CTPsyn catalyzes the latter. The study of CTPsyn activity in mammalian cells began in the 1970s, and various fascinating discoveries were made regarding the role of CTPsyn in cancer and development. However, its ability to fit into a cellular serpent-like structure, termed 'cytoophidia,' was only discovered a decade ago by three independent groups of scientists. Although the self-assembly of CTPsyn into a filamentous structure is evolutionarily conserved, the enzyme activity upon this self-assembly varies in different species. CTPsyn is required for cellular development and homeostasis. Changes in the expression of CTPsyn cause developmental changes in Drosophila melanogaster. A high level of CTPsyn activity and formation of cytoophidia are often observed in rapidly proliferating cells such as in stem and cancer cells. Meanwhile, the deficiency of CTPsyn causes severe immunodeficiency leading to immunocompromised diseases caused by bacteria, viruses, and parasites, making CTPsyn an attractive therapeutic target. Here, we provide an overview of the role of CTPsyn in cellular and disease perspectives along with its potential as a drug target.
Collapse
Affiliation(s)
- Shallinie Thangadurai
- grid.11875.3a0000 0001 2294 3534School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Morteza Bajgiran
- grid.11875.3a0000 0001 2294 3534School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Sharvin Manickam
- grid.11875.3a0000 0001 2294 3534School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Nethia Mohana-Kumaran
- grid.11875.3a0000 0001 2294 3534School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia
| | - Ghows Azzam
- grid.11875.3a0000 0001 2294 3534School of Biological Sciences, Universiti Sains Malaysia, 11800 Penang, Malaysia ,grid.454125.3Malaysia Genome and Vaccine Institute, National Institutes of Biotechnology Malaysia, Jalan Bangi, 43000 Kajang, Selangor Malaysia
| |
Collapse
|
5
|
Simonet JC, Burrell AL, Kollman JM, Peterson JR. Freedom of assembly: metabolic enzymes come together. Mol Biol Cell 2021; 31:1201-1205. [PMID: 32463766 PMCID: PMC7353150 DOI: 10.1091/mbc.e18-10-0675] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Many different enzymes in intermediate metabolism dynamically assemble filamentous polymers in cells, often in response to changes in physiological conditions. Most of the enzyme filaments known to date have only been observed in cells, but in a handful of cases structural and biochemical studies have revealed the mechanisms and consequences of assembly. In general, enzyme polymerization functions as a mechanism to allosterically tune enzyme kinetics, and it may play a physiological role in integrating metabolic signaling. Here, we highlight some principles of metabolic filaments by focusing on two well-studied examples in nucleotide biosynthesis pathways—inosine-5’-monophosphate (IMP) dehydrogenase and cytosine triphosphate (CTP) synthase.
Collapse
Affiliation(s)
| | - Anika L Burrell
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Justin M Kollman
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | | |
Collapse
|
6
|
Zhu X, Wu Y, Pan J, Li C, Huang J, Cui E, Chen Z, Zhou W, Chai X, Zhao S. Neuroinflammation Induction and Alteration of Hippocampal Neurogenesis in Mice Following Developmental Exposure to Gossypol. Int J Neuropsychopharmacol 2020; 24:419-433. [PMID: 33283869 PMCID: PMC8130202 DOI: 10.1093/ijnp/pyaa093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 11/12/2020] [Accepted: 12/03/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Neurogenesis in the neonatal period involves the proliferation and differentiation of neuronal stem/progenitor cells and the establishment of synaptic connections. This process plays a critical role in determining the normal development and maturation of the brain throughout life. Exposure to certain physical or chemical factors during the perinatal period can lead to many neuropathological defects that cause high cognitive dysfunction and are accompanied by abnormal hippocampal neurogenesis and plasticity. As an endocrine disruptor, gossypol is generally known to exert detrimental effects in animals exposed under experimental conditions. However, it is unclear whether gossypol affects neurogenesis in the hippocampal dentate gyrus during early developmental stages. METHODS Pregnant Institute of Cancer Research mice were treated with gossypol at a daily dose of 0, 20, and 50 mg/kg body weight from embryonic day 6.5 to postnatal day (P) 21. The changes of hippocampal neurogenesis as well as potential mechanisms were investigated by 5-bromo-2-deoxyuridine labeling, behavioral tests, immunofluorescence, quantitative reverse transcription-polymerase chain reaction, and western-blot analyses. RESULTS At P8, maternal gossypol exposure impaired neural stem cell proliferation in the dentate gyrus and decreased the number of newborn cells as a result of reduced proliferation of BLBP+ radial glial cells and Tbr2+ intermediate progenitor cells. At P21, the numbers of NeuN+ neurons and parvalbumin+ γ-aminobutyric acid-ergic interneurons were increased following 50 mg/kg gossypol exposure. In addition, gossypol induced hippocampal neuroinflammation, which may contribute to behavioral abnormalities and cognitive deficits and decrease synaptic plasticity. CONCLUSIONS Our findings suggest that developmental gossypol exposure affects hippocampal neurogenesis by targeting the proliferation and differentiation of neuronal stem/progenitor cells, cognitive functions, and neuroinflammation. The present data provide novel insights into the neurotoxic effects of gossypol on offspring.
Collapse
Affiliation(s)
- Xiaoyan Zhu
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China,Correspondence: Xiaoyan Zhu, PhD, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, PR China ()
| | - Yongji Wu
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Jiarong Pan
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Cixia Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Jian Huang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Enhui Cui
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Ziluo Chen
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Wentai Zhou
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| | - Xuejun Chai
- College of Basic Medicine, Xi’An Medical University, Xi’An, PR China
| | - Shanting Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, PR China
| |
Collapse
|
7
|
Montrose K, López Cabezas RM, Paukštytė J, Saarikangas J. Winter is coming: Regulation of cellular metabolism by enzyme polymerization in dormancy and disease. Exp Cell Res 2020; 397:112383. [PMID: 33212148 DOI: 10.1016/j.yexcr.2020.112383] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 11/12/2020] [Accepted: 11/14/2020] [Indexed: 12/20/2022]
Abstract
Metabolism feeds growth. Accordingly, metabolism is regulated by nutrient-sensing pathways that converge growth promoting signals into biosynthesis by regulating the activity of metabolic enzymes. When the environment does not support growth, organisms invest in survival. For cells, this entails transitioning into a dormant, quiescent state (G0). In dormancy, the activity of biosynthetic pathways is dampened, and catabolic metabolism and stress tolerance pathways are activated. Recent work in yeast has demonstrated that dormancy is associated with alterations in the physicochemical properties of the cytoplasm, including changes in pH, viscosity and macromolecular crowding. Accompanying these changes, numerous metabolic enzymes transition from soluble to polymerized assemblies. These large-scale self-assemblies are dynamic and depolymerize when cells resume growth. Here we review how enzyme polymerization enables metabolic plasticity by tuning carbohydrate, nucleic acid, amino acid and lipid metabolic pathways, with particular focus on its potential adaptive value in cellular dormancy.
Collapse
Affiliation(s)
- Kristopher Montrose
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Finland; Research Programme in Molecular and Integrative Biosciences, Faculty of Biological and Environmental Sciences, University of Helsinki, Finland
| | - Rosa María López Cabezas
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Finland; Research Programme in Molecular and Integrative Biosciences, Faculty of Biological and Environmental Sciences, University of Helsinki, Finland
| | - Jurgita Paukštytė
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Finland; Research Programme in Molecular and Integrative Biosciences, Faculty of Biological and Environmental Sciences, University of Helsinki, Finland
| | - Juha Saarikangas
- Helsinki Institute of Life Science, HiLIFE, University of Helsinki, Finland; Research Programme in Molecular and Integrative Biosciences, Faculty of Biological and Environmental Sciences, University of Helsinki, Finland; Neuroscience Center, University of Helsinki, Finland.
| |
Collapse
|
8
|
Zhu X, Wu Y, Li C, Yan W, Pan J, Wang S, Zhao S. Prenatal Exposure to Gossypol Impairs Corticogenesis of Mouse. Front Neurosci 2020; 14:318. [PMID: 32317927 PMCID: PMC7146080 DOI: 10.3389/fnins.2020.00318] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 03/18/2020] [Indexed: 12/16/2022] Open
Abstract
Gossypol is a yellow polyphenolic compounds extracted from roots, stems and seeds of cotton plants. Excessive intake of gossypol induces severe pathological signs of toxicity in livestock and wildlife. Currently, gossypol has received widespread attention for its toxic effects on the reproductive system. However, reports of the effects of gossypol during corticogenesis and the development of the mouse cerebral cortex are unavailable. In the present study, gossypol was orally administrated at a dose of 0, 20, and 50 mg/kg body weight/day to pregnant mice from embryonic day 6.5 to the time of sample collection. We used in utero electroporation and immunofluorescence to demonstrate that gossypol impaired cortical neuronal migration. Furthermore, labeling with 5-bromo-2-deoxyuridine and western blot analysis revealed that gossypol disturbed the balance between proliferation and differentiation of neural progenitors, inhibited neural progenitor cell proliferation, neuronal differentiation, and maturation. Additionally, cortical progenitor apoptotic cell death increased in the developing gossypol-treated cortex, which was associated with NF-κB and MAPK pathways. In conclusion, our findings indicate that gossypol exposure disrupted neurogenesis in the developing neocortex, suggesting the potentially harmful impact of gossypol on the cerebral cortex development of humans and livestock.
Collapse
Affiliation(s)
- Xiaoyan Zhu
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Yongji Wu
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Cixia Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Wenyong Yan
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Jiarong Pan
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Shuzhong Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| | - Shanting Zhao
- College of Veterinary Medicine, Northwest A&F University, Yangling, China
| |
Collapse
|
9
|
Andreadis C, Hulme L, Wensley K, Liu JL. The TOR pathway modulates cytoophidium formation in Schizosaccharomyces pombe. J Biol Chem 2019; 294:14686-14703. [PMID: 31431504 PMCID: PMC6779450 DOI: 10.1074/jbc.ra119.009913] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 08/09/2019] [Indexed: 12/30/2022] Open
Abstract
CTP synthase (CTPS) has been demonstrated to form evolutionarily-conserved filamentous structures termed cytoophidia whose exact cellular functions remain unclear, but they may play a role in intracellular compartmentalization. We have previously shown that the mammalian target of rapamycin complex 1 (mTORC1)-S6K1 pathway mediates cytoophidium assembly in mammalian cells. Here, using the fission yeast Schizosaccharomyces pombe as a model of a unicellular eukaryote, we demonstrate that the target of rapamycin (TOR)-signaling pathway regulates cytoophidium formation (from the S. pombe CTPS ortholog Cts1) also in S. pombe Conducting a systematic analysis of all viable single TOR subunit-knockout mutants and of several major downstream effector proteins, we found that Cts1 cytoophidia are significantly shortened and often dissociate when TOR is defective. We also found that the activities of the downstream effector kinases of the TORC1 pathway, Sck1, Sck2, and Psk1 S6, as well as of the S6K/AGC kinase Gad8, the major downstream effector kinase of the TORC2 pathway, are necessary for proper cytoophidium filament formation. Interestingly, we observed that the Crf1 transcriptional corepressor for ribosomal genes is a strong effector of Cts1 filamentation. Our findings connect TOR signaling, a major pathway required for cell growth, with the compartmentalization of the essential nucleotide synthesis enzyme CTPS, and we uncover differences in the regulation of its filamentation among higher multicellular and unicellular eukaryotic systems.
Collapse
Affiliation(s)
- Christos Andreadis
- School of Life Sciences and Technology, ShanghaiTech University, 201210 Shanghai, China
| | - Lydia Hulme
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Katherine Wensley
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Ji-Long Liu
- School of Life Sciences and Technology, ShanghaiTech University, 201210 Shanghai, China .,MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| |
Collapse
|
10
|
Cheng X, Li K, Liu M, Xu M, Hu X, Yan R, Förster E, Zhao S. The effect of P85 on neuronal proliferation and differentiation during development of mouse cerebral cortex. Dev Biol 2018; 441:95-103. [DOI: 10.1016/j.ydbio.2018.06.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 05/23/2018] [Accepted: 06/23/2018] [Indexed: 12/28/2022]
|
11
|
Löffler M, Carrey EA, Zameitat E. New perspectives on the roles of pyrimidines in the central nervous system. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2018; 37:290-306. [PMID: 29693489 DOI: 10.1080/15257770.2018.1453076] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Since 1956, when exogenous uridine and cytidine were found to be necessary for the maintenance of perfused rat brain function, the co-existence of de novo synthesis, salvage pathways and removal of pyrimidine bases in the CNS has been a controversial subject. Here, we review studies on metabolites and enzymes of pyrimidine metabolism through more than 60 years. In view of known and newly-described inherited pyrimidine and purine disorders - some with complex clinical profiles of neurological impairments - we underline the necessity to investigate how the different pathways work together in the developing brain and then sustain plasticity, regeneration and neuro-transmission in the adult CNS. Experimentally, early incorporation studies in animal brain slices and homogenates with radio-labelled nucleosides or precursors demonstrated salvage activity or de novo synthesis. Later, the nucleoside transporters and organic anionic transporters underlying uptake of metabolites and anti-pyrimidine drugs in the CNS were identified. Recently, the expression of de novo enzymes in glial cells and neurons was verified using (immuno) histochemical and in-situ-hybridization techniques. Adult brain was shown to take up or produce all pyrimidine (deoxy) ribonucleosides or, after uptake and phosphorolysis of nucleosides, to make use of ribose for different purposes, including energy. More recently, non-canonical pyrimidine bases (5mC, 5hmC) have been found most notably in brain, pointing to considerable postreplicative DNA metabolism, with the need for pyrimidine-specific enzymes. Even more perspectives are emerging, with advances in genome analysis and in the manipulation of expression from the gene.
Collapse
Affiliation(s)
- M Löffler
- a Institute of Physiological Chemistry, Faculty of Medicine, Philipps-University Marburg , Marburg , Germany
| | - E A Carrey
- b Institute of Child Health, University College London , GB
| | - E Zameitat
- a Institute of Physiological Chemistry, Faculty of Medicine, Philipps-University Marburg , Marburg , Germany
| |
Collapse
|