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Sari Y, Swiss GM, Alrashedi FA, Baeshen KA, Alshammari SA, Alsharari SD, Ali N, Alasmari AF, Alhoshani A, Alameen AA, Childers WE, Abou-Gharbia M, Alasmari F. Effects of novel beta-lactam, MC-100093, and ceftriaxone on astrocytic glutamate transporters and neuroinflammatory factors in nucleus accumbens of C57BL/6 mice exposed to escalated doses of morphine. Saudi Pharm J 2024; 32:102108. [PMID: 38868175 PMCID: PMC11166880 DOI: 10.1016/j.jsps.2024.102108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2024] Open
Abstract
Chronic exposure to opioids can lead to downregulation of astrocytic glutamate transporter 1 (GLT-1), which regulates the majority of glutamate uptake. Studies from our lab revealed that beta-lactam antibiotic, ceftriaxone, attenuated hydrocodone-induced downregulation of GLT-1 as well as cystine/glutamate antiporter (xCT) expression in central reward brain regions. In this study, we investigated the effects of escalating doses of morphine and tested the efficacy of novel synthetic non-antibiotic drug, MC-100093, and ceftriaxone in attenuating the effects of morphine exposure in the expression of GLT-1, xCT, and neuroinflammatory factors (IL-6 and TGF-β) in the nucleus accumbens (NAc). This study also investigated the effects of morphine and beta-lactams in locomotor activity, spontaneous alternation percentage (SAP) and number of entries in Y maze since opioids have effects in locomotor sensitization. Mice were exposed to moderate dose of morphine (20 mg/kg, i.p.) on days 1, 3, 5, 7, and a higher dose of morphine (150 mg/kg, i.p.) on day 9, and these mice were then behaviorally tested and euthanized on Day 10. Western blot analysis showed that exposure to morphine downregulated GLT-1 and xCT expression in the NAc, and both MC-100093 and ceftriaxone attenuated these effects. In addition, morphine exposure increased IL-6 mRNA and TGF-β mRNA expression, and MC-100093 and ceftriaxone attenuated only the effect on IL-6 mRNA expression in the NAc. Furthermore, morphine exposure induced an increase in distance travelled, and MC-100093 and ceftriaxone attenuated this effect. In addition, morphine exposure decreased the SAP and increased the number of arm entries in Y maze, however, neither MC-100093 nor ceftriaxone showed any attenuating effect. Our findings demonstrated for the first time that MC-100093 and ceftriaxone attenuated morphine-induced downregulation of GLT-1 and xCT expression, and morphine-induced increase in neuroinflammatory factor, IL-6, as well as hyperactivity. These findings revealed the beneficial therapeutic effects of MC-100093 and ceftriaxone against the effects of exposure to escalated doses of morphine.
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Affiliation(s)
- Youssef Sari
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, OH 43614, USA
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ghadeer M.S. Swiss
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Fatin A. Alrashedi
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Kholoud A. Baeshen
- Department of Forensic Sciences, College of Criminal Justice, Naif Arab University for Security Sciences, Riyadh, Saudi Arabia
| | - Sultan A. Alshammari
- Department of Forensic Sciences, College of Criminal Justice, Naif Arab University for Security Sciences, Riyadh, Saudi Arabia
| | - Shakir D. Alsharari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Nemat Ali
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Abdullah F. Alasmari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ali Alhoshani
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Alaa A. Alameen
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Wayne E. Childers
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, PA 19140, USA
| | - Magid Abou-Gharbia
- Department of Pharmaceutical Sciences, Temple University School of Pharmacy, Philadelphia, PA 19140, USA
| | - Fawaz Alasmari
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
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Jiang R, Li L, Wang B, Liu L, Liu L, Xian X, Li W. Ceftriaxone Modulates Ubiquitination of α-Amino-3-Hydroxy-5-Methyl-4-Isoxazole Propionic Acid Receptors to Improve Long-Term Potentiation Impairment Induced by Exogenous β-Amyloid in a Glutamate Transporter-1 Dependent Manner. Mol Neurobiol 2024:10.1007/s12035-024-04037-3. [PMID: 38374316 DOI: 10.1007/s12035-024-04037-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Accepted: 02/09/2024] [Indexed: 02/21/2024]
Abstract
Α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptors (AMPARs) are crucial for properties of synaptic plasticity, such as long-term potentiation (LTP). LTP impairment can occur early in the onset of Alzheimer's disease (AD). The downregulation or decreased abundance of AMPAR expression in the postsynaptic membrane is closely associated with LTP impairment. Ceftriaxone (Cef) can improve LTP impairment in the early stages of AD in a mouse model. The purpose of this study was to explore the mechanism underlying this process from the aspects of AMPAR expression and ubiquitination degree. In this study, we found that β-amyloid (Aβ) treatment induced hippocampal LTP impairment and AMPAR downregulation and ubiquitination. Cef pretreatment ameliorated Aβ-induced hippocampal LTP impairment, reduced AMPAR ubiquitination, and increased AMPAR expression, especially in the plasma membrane, in Aβ-treated mice. Administration of USP46 siRNA and DHK (a specific blocker of glutamate transporter-1) significantly inhibited the above effects of Cef, suggesting a role for anti-AMPAR ubiquitination and upregulation of glutamate transporter-1 (GLT-1) in the Cef-induced improvements mentioned above. The above findings demonstrate that pretreatment with Cef effectively mitigated Aβ-induced impairment of hippocampal LTP by suppressing the ubiquitination process of AMPARs in a GLT-1-dependent manner. These results provide novel insights into the underlying mechanisms elucidating the anti-AD by Cef.
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Affiliation(s)
- Rui Jiang
- Hebei Key Laboratory of Critical Disease Mechanism and Intervention, Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, People's Republic of China
- School of Nursing, Hebei Medical University, 309 Jianhua South Street, Shijiazhuang, 050000, People's Republic of China
| | - Li Li
- Central Laboratory, The Second Hospital of Hebei Medical University, 215 Heping West Road, Shijiazhuang, 050000, People's Republic of China
| | - Bu Wang
- Department of Emergency Critical Care Medicine, The Second Hospital of Hebei Medical University, 215 Heping West Road, Shijiazhuang, 050000, People's Republic of China
| | - Lizhe Liu
- Hebei Key Laboratory of Critical Disease Mechanism and Intervention, Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, People's Republic of China
| | - Lirong Liu
- Hebei Key Laboratory of Critical Disease Mechanism and Intervention, Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, People's Republic of China
| | - Xiaohui Xian
- Hebei Key Laboratory of Critical Disease Mechanism and Intervention, Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, People's Republic of China.
| | - Wenbin Li
- Hebei Key Laboratory of Critical Disease Mechanism and Intervention, Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, People's Republic of China.
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Li L, Li W, Jiang W, Xu R. Sulbactam protects neurons against double neurotoxicity of amyloid beta and glutamate load by upregulating glial glutamate transporter 1. Cell Death Discov 2024; 10:64. [PMID: 38320997 PMCID: PMC10847450 DOI: 10.1038/s41420-024-01827-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 01/15/2024] [Accepted: 01/17/2024] [Indexed: 02/08/2024] Open
Abstract
Amyloid beta (Abeta) synergistically enhances excitotoxicity of glutamate load by impairing glutamate transporter 1 (GLT1) expression and function, which exacerbates the development of Alzheimer's disease (AD). Our previous studies suggested that sulbactam can upregulate the expression levels and capacity of GLT1. Therefore, this study aims to investigate whether sulbactam improves neuronal tolerance against neurotoxicity of Abeta and glutamate load by up-regulating GLT1 in primary neuron-astrocyte co-cultures. Early postnatal P0-P1 Wistar rat pups' cortices were collected for primary neuron-astrocyte cultures. Hoechst-propidium iodide (HO-PI) stain and lactate dehydrogenase (LDH) assays were used to analyze neuronal death. Cell counting kit 8 (CCK8) was applied to determine cell viability. Immunofluorescence staining and western blotting were used to assess protein expressions including GLT1, B-cell lymphoma 2 (BCL2), BCL2 associated X (BAX), and cleaved caspase 3 (CCP3). Under the double effect of Abeta and glutamate load, more neurons were lost than that induced by Abeta or glutamate alone, shown as decreased cell viability, increased LDH concentration in the cultural medium, HO-PI positive stains, high CCP3 expression, and high BAX/BCL2 ratio resulting from increased BAX and decreased BCL2 expressions. Notably, pre-incubation with sulbactam significantly attenuated the neuronal loss and activation of apoptosis induced by both Abeta and glutamate in a dose-dependent manner. Simultaneously, both astrocytic and neuronal GLT1 expressions were upregulated after sulbactam incubation. Taken together, it could be concluded that sulbactam protected neurons against double neurotoxicity of Abeta and glutamate load by upregulating GLT1 expression. The conclusion provides evidence for potential intervention using sulbactam in AD research.
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Affiliation(s)
- Li Li
- The Central Laboratory, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
| | - Wenbin Li
- Department of Pathophysiology, Hebei Medical University, Shijiazhuang, Hebei, China
| | - Wei Jiang
- Hebei Collaborative Innovation Center for Cardio-Cerebrovascular Disease, Hebei Vascular Homeostasis Key Laboratory, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
| | - Renhao Xu
- Hebei Collaborative Innovation Center for Cardio-Cerebrovascular Disease, Hebei Vascular Homeostasis Key Laboratory, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei, China
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Naumenko Y, Yuryshinetz I, Zabenko Y, Pivneva T. Mild traumatic brain injury as a pathological process. Heliyon 2023; 9:e18342. [PMID: 37519712 PMCID: PMC10372741 DOI: 10.1016/j.heliyon.2023.e18342] [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: 11/22/2022] [Revised: 07/10/2023] [Accepted: 07/13/2023] [Indexed: 08/01/2023] Open
Abstract
Traumatic brain injury (TBI) is defined as dysfunction or other evidence of brain pathology caused by external physical force. More than 69 million new cases of TBI are registered worldwide each year, 80% of them - mild TBI. Based on the physical mechanism of induced trauma, we can separate its pathophysiology into primary and secondary injuries. Many literature sources have confirmed that mechanically induced brain injury initiates ionic, metabolic, inflammatory, and neurovascular changes in the CNS, which can lead to acute, subacute, and chronic neurological consequences. Despite the global nature of the disease, its high heterogeneity, lack of a unified classification system, rapid fluctuation of epidemiological trends, and variability of long-term consequences significantly complicate research and the development of new therapeutic strategies. In this review paper, we systematize current knowledge of biomechanical and molecular mechanisms of mild TBI and provide general information on the classification and epidemiology of this complex disorder.
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Affiliation(s)
- Yana Naumenko
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
| | - Irada Yuryshinetz
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
| | - Yelyzaveta Zabenko
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
| | - Tetyana Pivneva
- Bogomoletz Institute of Physiology, Department of Sensory Signalization, Kyiv, Ukraine
- Kyiv Academic University, Kyiv, Ukraine
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Liu LZ, Fan SJ, Gao JX, Li WB, Xian XH. Ceftriaxone ameliorates hippocampal synapse loss by inhibiting microglial/macrophages activation in glial glutamate transporter-1 dependent manner in the APP/PS1 mouse model of Alzheimer's disease. Brain Res Bull 2023:110683. [PMID: 37301482 DOI: 10.1016/j.brainresbull.2023.110683] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 05/29/2023] [Accepted: 06/06/2023] [Indexed: 06/12/2023]
Abstract
Synapse loss is a major contributor to cognitive dysfunction in Alzheimer's disease (AD). Impairments in the expression and/or glutamate uptake activity of glia glutamate transporter-1 (GLT-1) contribute to synapse loss in AD. Hence, targeting the restoration of GLT-1 activity may have potential for alleviating synapse loss in AD. Ceftriaxone (Cef) can upregulate the expression and glutamate uptake activity of GLT-1 in many disease models, including those for AD. The present study investigated the effects of Cef on synapse loss and the role of GLT-1 using APP/PS1 transgenic and GLT-1 knockdown APP/PS1 AD mice. Furthermore, the involvement of microglia in the process was investigated due to its important role in synapse loss in AD. We found that Cef treatment significantly ameliorated synapse loss and dendritic degeneration in APP/PS1 AD mice, evidenced by an increased dendritic spine density, decreased dendritic beading density, and upregulated levels of postsynaptic density protein 95 (PSD95) and synaptophysin. The effects of Cef were suppressed by GLT-1 knockdown in GLT-1+/-/APP/PS1 AD mice. Simultaneously, Cef treatment inhibited ionized calcium binding adapter molecule 1 (Iba1) expression, decreased the proportion of CD11b+CD45hi cells, declined interleukin-6 (IL-6) content, and reduced the co-expression of Iba1 with PSD95 or synaptophysin in APP/PS1 AD mice. In conclusion, Cef treatment ameliorated synapse loss and dendritic degeneration in APP/PS1 AD mice in a GLT-1-dependent manner, and the inhibitory effect of Cef on the activation of microglia/macrophages and their phagocytosis for synaptic elements contributed to the mechanism.
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Affiliation(s)
- Li-Zhe Liu
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, P.R. China; Department of Pathophysiology, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, P. R. China.
| | - Shu-Juan Fan
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, P.R. China; Department of Pathophysiology, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, P. R. China.
| | - Jun-Xia Gao
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, P.R. China; Department of Pathophysiology, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, P. R. China.
| | - Wen-Bin Li
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, P.R. China; Department of Pathophysiology, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, P. R. China.
| | - Xiao-Hui Xian
- Department of Pathophysiology, Neuroscience Research Center, Hebei Medical University, P.R. China; Department of Pathophysiology, Hebei Medical University, 361 Zhongshan East Road, Shijiazhuang, 050017, P. R. China.
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6
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Wang C, Liu H, Xu S, Deng Y, Xu B, Yang T, Liu W. Ferroptosis and Neurodegenerative Diseases: Insights into the Regulatory Roles of SLC7A11. Cell Mol Neurobiol 2023:10.1007/s10571-023-01343-7. [PMID: 36988772 DOI: 10.1007/s10571-023-01343-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 03/22/2023] [Indexed: 03/30/2023]
Abstract
Programed cell death plays a key role in promoting human development and maintaining homeostasis. Ferroptosis is a recently identified pattern of programmed cell death that is closely associated with the onset and progression of neurodegenerative diseases. Ferroptosis is mainly caused by the intracellular accumulation of iron-dependent lipid peroxides. The cysteine/glutamate antibody Solute carrier family 7 member 11 (SLC7A11, also known as xCT) functions to import cysteine for glutathione biosynthesis and antioxidant defense. SLC7A11 has a significant impact on ferroptosis, and inhibition of SLC7A11 expression promotes ferroptosis. Moreover, SLC7A11 is also closely associated with neurodegenerative diseases. In this paper, we summarize the relationship between ferroptosis and neurodegenerative diseases and the role of SLC7A11 during this process. The various regulatory mechanisms of SLC7A11 are also discussed. In conclusion, we are looking forward to a theoretical basis for further understanding the occurrence and development of ferroptosis in SLC7A11 and neurodegenerative diseases, and to seek new clues for the treatment of neurodegenerative diseases.
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Affiliation(s)
- Chen Wang
- Department of Environmental Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, Liaoning, China
| | - Haihui Liu
- Department of Environmental Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, Liaoning, China
| | - Si Xu
- Department of Environmental Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, Liaoning, China
| | - Yu Deng
- Department of Environmental Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, Liaoning, China
| | - Bin Xu
- Department of Environmental Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, Liaoning, China
| | - Tianyao Yang
- Department of Environmental Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, Liaoning, China
| | - Wei Liu
- Department of Environmental Health, School of Public Health, China Medical University, No. 77 Puhe Road, Shenbei New District, Shenyang, 110122, Liaoning, China.
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7
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Smaga I, Gawlińska K, Gawliński D, Surówka P, Filip M. A maternal high-fat diet during pregnancy and lactation disrupts short-term memory functions via altered hippocampal glutamatergic signaling in female rat offspring. Behav Brain Res 2023; 445:114396. [PMID: 36934986 DOI: 10.1016/j.bbr.2023.114396] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/07/2023] [Accepted: 03/16/2023] [Indexed: 03/19/2023]
Abstract
A maternal high-fat diet (HFD) provokes changes in the offspring's brain's structure, function, and development. These changes may cause neuropsychiatric disorders in the early life of offspring the basis of which may be memory impairment. In this study, the effects of maternal HFD during pregnancy and lactation on the short-term memory in adolescent and young adult offspring were evaluated. We analyzed the expression of genes encoding the glutamatergic transporters in the hippocampus to verify the association between changes in glutamatergic transporters and behavioral changes in offspring. Next, we examined whether maternal diet-induced changes in the mRNA levels of genes encoding the NMDA receptor subunits and the AMPA receptor subunits, as well as BDNF in this structure in offspring. All significant changes were validated at the protein level. We found that a maternal HFD during pregnancy and lactation disrupts short-term memory in adolescent and young adult females. The latter change is likely related to the dysregulation of hippocampal levels of GluN2B subunit of NMDA receptors and of reduced levels of BDNF. In summary, we showed that a maternal HFD during pregnancy and lactation triggered several changes within the glutamatergic system in the hippocampus of rat offspring, which may be related to producing behavioral changes in offspring.
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Affiliation(s)
- Irena Smaga
- Maj Institute of Pharmacology Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smętna 12, 31-343 Kraków, Poland.
| | - Kinga Gawlińska
- Maj Institute of Pharmacology Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smętna 12, 31-343 Kraków, Poland
| | - Dawid Gawliński
- Maj Institute of Pharmacology Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smętna 12, 31-343 Kraków, Poland
| | - Paulina Surówka
- Maj Institute of Pharmacology Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smętna 12, 31-343 Kraków, Poland
| | - Małgorzata Filip
- Maj Institute of Pharmacology Polish Academy of Sciences, Department of Drug Addiction Pharmacology, Smętna 12, 31-343 Kraków, Poland
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Brymer KJ, Hurley EP, Barron JC, Mukherjee B, Barnes JR, Nafar F, Parsons MP. Asymmetric dysregulation of glutamate dynamics across the synaptic cleft in a mouse model of Alzheimer's disease. Acta Neuropathol Commun 2023; 11:27. [PMID: 36788598 PMCID: PMC9926626 DOI: 10.1186/s40478-023-01524-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 01/28/2023] [Indexed: 02/16/2023] Open
Abstract
Most research on glutamate spillover focuses on the deleterious consequences of postsynaptic glutamate receptor overactivation. However, two decades ago, it was noted that the glial coverage of hippocampal synapses is asymmetric: astrocytic coverage of postsynaptic sites exceeds coverage of presynaptic sites by a factor of four. The fundamental relevance of this glial asymmetry remains poorly understood. Here, we used the glutamate biosensor iGluSnFR, and restricted its expression to either CA3 or CA1 neurons to visualize glutamate dynamics at pre- and postsynaptic microenvironments, respectively. We demonstrate that inhibition of the primarily astrocytic glutamate transporter-1 (GLT-1) slows glutamate clearance to a greater extent at presynaptic compared to postsynaptic membranes. GLT-1 expression was reduced early in a mouse model of AD, resulting in slower glutamate clearance rates at presynaptic but not postsynaptic membranes that opposed presynaptic short-term plasticity. Overall, our data demonstrate that the presynapse is particularly vulnerable to GLT-1 dysfunction and may have implications for presynaptic impairments in a variety of brain diseases.
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Affiliation(s)
- Kyle J. Brymer
- grid.25055.370000 0000 9130 6822Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6 Canada
| | - Emily P. Hurley
- grid.25055.370000 0000 9130 6822Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6 Canada
| | - Jessica C. Barron
- grid.25055.370000 0000 9130 6822Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6 Canada
| | - Bandhan Mukherjee
- grid.25055.370000 0000 9130 6822Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6 Canada
| | - Jocelyn R. Barnes
- grid.25055.370000 0000 9130 6822Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6 Canada
| | - Firoozeh Nafar
- grid.25055.370000 0000 9130 6822Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6 Canada
| | - Matthew P. Parsons
- grid.25055.370000 0000 9130 6822Division of Biomedical Sciences, Faculty of Medicine, Memorial University of Newfoundland, St. John’s, NL A1B 3V6 Canada
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Mirzaei N, Davis N, Chau TW, Sastre M. Astrocyte Reactivity in Alzheimer's Disease: Therapeutic Opportunities to Promote Repair. Curr Alzheimer Res 2021; 19:1-15. [PMID: 34719372 DOI: 10.2174/1567205018666211029164106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/02/2021] [Accepted: 07/31/2021] [Indexed: 11/22/2022]
Abstract
Astrocytes are fast climbing the ladder of importance in neurodegenerative disorders, particularly in Alzheimer's disease (AD), with the prominent presence of reactive astrocytes sur- rounding amyloid β- plaques, together with activated microglia. Reactive astrogliosis, implying morphological and molecular transformations in astrocytes, seems to precede neurodegeneration, suggesting a role in the development of the disease. Single-cell transcriptomics has recently demon- strated that astrocytes from AD brains are different from "normal" healthy astrocytes, showing dys- regulations in areas such as neurotransmitter recycling, including glutamate and GABA, and im- paired homeostatic functions. However, recent data suggest that the ablation of astrocytes in mouse models of amyloidosis results in an increase in amyloid pathology as well as in the inflammatory profile and reduced synaptic density, indicating that astrocytes mediate neuroprotective effects. The idea that interventions targeting astrocytes may have great potential for AD has therefore emerged, supported by a range of drugs and stem cell transplantation studies that have successfully shown a therapeutic effect in mouse models of AD. In this article, we review the latest reports on the role and profile of astrocytes in AD brains and how manipulation of astrocytes in animal mod- els has paved the way for the use of treatments enhancing astrocytic function as future therapeutic avenues for AD.
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Affiliation(s)
- Nazanin Mirzaei
- Department of Neurosurgery, Maxine Dunitz Neurosurgical Research Institute, Cedars-Sinai Medical Center, 127 S. San Vicente Blvd., Los Angeles, CA, 90048. United States
| | - Nicola Davis
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
| | - Tsz Wing Chau
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
| | - Magdalena Sastre
- Department of Brain Sciences, Imperial College London, Hammer-smith Hospital, Du Cane Road, LondonW12 0NN. United Kingdom
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