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Lokesh M, Bandaru LJM, Rajanna A, Rao JS, Challa S. Unveiling Potential Neurotoxic Mechansisms: Pb-Induced Activation of CDK5-p25 Signaling Axis in Alzheimer's Disease Development, Emphasizing CDK5 Inhibition and Formation of Toxic p25 Species. Mol Neurobiol 2024; 61:3090-3103. [PMID: 37968421 DOI: 10.1007/s12035-023-03783-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 11/06/2023] [Indexed: 11/17/2023]
Abstract
Alzheimer's disease (AD) is a complex neurodegenerative disorder with an etiology influenced by various genetic and environmental factors. Heavy metals, such as lead (Pb), have been implicated in AD pathogenesis, but the underlying mechanisms remain poorly understood. This study investigates the potential neurodegenerative role of Pb and amyloid β peptides (1-40 and 25-35) via their interaction with cyclin-dependent kinase 5 (CDK5) and its activator, p25, in an attempt to unravel the molecular basis of Pb-induced neurotoxicity in neuronal cells. To this end, a CDK5 inhibitor was utilized to selectively inhibit CDK5 activity and investigate its impact on neurodegeneration. The results revealed that Pb exposure led to elevated Pb uptake (56.7% at 15 μM Pb) and disturbances in intracellular calcium (19.6% increase upon Pb treatment). The results revealed a significant decrease in total antioxidant capacity (by 88.6% upon Pb treatment) and also elevation in protein carbonylation (by 26.2% upon Pb and Aβp's combination treatment), indicative of oxidative damage, suggesting an impaired cellular defence against oxidative stress and elevated DNA oxidative damage (178 pg/ml and 182 pg/ml of 8-OH-dG upon Pb and All treatment). Additionally, dysregulations in levels of calpain, p25-35 and CDK5 are observed and markers associated with antioxidant metabolism (phospho-Peroxiredoxin 1), DNA damage responses (phospho-ATM and phospho-p53), and nuclear membrane disruption (phospho-lamin A/C) were observed, supporting the role of Pb-induced CDK5-p25 signaling in AD pathogenesis. These findings shed light on the intricate molecular events underlying Pb-induced neurotoxicity and provide valuable insights into the mechanisms that contribute to AD development.
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Affiliation(s)
- Murumulla Lokesh
- Cell Biology Division, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India
| | - Lakshmi Jaya Madhuri Bandaru
- Cell Biology Division, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India
| | - Ajumeera Rajanna
- Cell Biology Division, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India
| | - J Sreenivasa Rao
- Cell Biology Division, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India
| | - Suresh Challa
- Cell Biology Division, National Institute of Nutrition, Indian Council of Medical Research (ICMR), Hyderabad, Telangana, 500007, India.
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Yu G, Wu L, Su Q, Ji X, Zhou J, Wu S, Tang Y, Li H. Neurotoxic effects of heavy metal pollutants in the environment: Focusing on epigenetic mechanisms. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 345:123563. [PMID: 38355086 DOI: 10.1016/j.envpol.2024.123563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 02/04/2024] [Accepted: 02/11/2024] [Indexed: 02/16/2024]
Abstract
The pollution of heavy metals (HMs) in the environment is a significant global environmental issue, characterized by its extensive distribution, severe contamination, and profound ecological impacts. Excessive exposure to heavy metal pollutants can damage the nervous system. However, the mechanisms underlying the neurotoxicity of most heavy metals are not completely understood. Epigenetics is defined as a heritable change in gene function that can influence gene and subsequent protein expression levels without altering the DNA sequence. Growing evidence indicates that heavy metals can induce neurotoxic effects by triggering epigenetic changes and disrupting the epigenome. Compared with genetic changes, epigenetic alterations are more easily reversible. Epigenetic reprogramming techniques, drugs, and certain nutrients targeting specific epigenetic mechanisms involved in gene expression regulation are emerging as potential preventive or therapeutic tools for diseases. Therefore, this review provides a comprehensive overview of epigenetic modifications encompassing DNA/RNA methylation, histone modifications, and non-coding RNAs in the nervous system, elucidating their association with various heavy metal exposures. These primarily include manganese (Mn), mercury (Hg), lead (Pb), cobalt (Co), cadmium (Cd), nickel (Ni), sliver (Ag), toxic metalloids arsenic (As), and etc. The potential epigenetic mechanisms in the etiology, precision prevention, and target therapy of various neurodevelopmental disorders or different neurodegenerative diseases are emphasized. In addition, the current gaps in research and future areas of study are discussed. From a perspective on epigenetics, this review offers novel insights for prevention and treatment of neurotoxicity induced by heavy metal pollutants.
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Affiliation(s)
- Guangxia Yu
- Key Lab of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Lingyan Wu
- Key Lab of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Qianqian Su
- Key Lab of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Xianqi Ji
- Key Lab of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Jinfu Zhou
- Key Lab of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Fujian Maternity and Child Hospital College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou 350001, China
| | - Siying Wu
- Key Lab of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Department of Epidemiology and Health Statistics, School of Public Health, Fujian Medical University, Fuzhou 350122, China
| | - Ying Tang
- Fujian Center for Prevention and Control Occupational Diseases and Chemical Poisoning, Fuzhou 350125, China
| | - Huangyuan Li
- Key Lab of Environment and Health, School of Public Health, Fujian Medical University, Fuzhou 350122, China; Department of Preventive Medicine, School of Public Health, Fujian Medical University, Fuzhou 350122, China.
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Zou RX, Gu X, Huang C, Wang HL, Chen XT. Chronic Pb exposure impairs learning and memory abilities by inhibiting excitatory projection neuro-circuit of the hippocampus in mice. Toxicology 2024; 502:153717. [PMID: 38160928 DOI: 10.1016/j.tox.2023.153717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 12/21/2023] [Accepted: 12/28/2023] [Indexed: 01/03/2024]
Abstract
Lead (Pb) is an environmental neurotoxic metal. Chronic Pb exposure causes behavioral changes in humans and rodents, such as dysfunctional learning and memory. Nevertheless, it is not clear whether Pb exposure disrupts the neural circuit. Thus, here we aim at investigating the effects the chronic Pb exposure on neural-behavioral and neural circuits in mice from prenatal to postnatal day (PND) 63. Pregnant mice and their male offspring were treated with Pb (150 ppm) until postnatal day 63. In this study, several behavior tests and Golgi-Cox staining methods were used to assess spatial memory ability and synaptogenesis. Virus-based tracing systems and immunohistochemistry assays were used to test the relevance of chronic Pb exposure with disrupted neural circuits. The behavioral experiments and Golgi-Cox staining results showed that Pb exposure impaired spatial memory and spine density in mice. The virus tracing results revealed that the Entorhinal cortex (EC) neurons could be directly projected to Cornuammonis 1 (CA1) and Dentate gyrus (DG), forming a critical circuit inhibited, in either a direct or indirect way, by Pb invasion. In addition, excitatory neural input from EC(labeled with CaMKII)to CA1 and DG was significantly attenuated by Pb exposure. In conclusion, our data indicated that Pb significantly impaired the excitatory connections from EC to the hippocampus (CA1 and DG), providing a novel neuro-circuitry basis for Pb neurotoxicity.
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Affiliation(s)
- Rong-Xin Zou
- School of Pharmacy, Anhui University of Chinese Medicine, Hefei, Anhui 230012, PR China
| | - Xiaozhen Gu
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Chenqing Huang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Hui-Li Wang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China.
| | - Xiang-Tao Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui 230032, PR China.
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Zhou R, Huang C, Bi N, Li L, Li C, Gu X, Song Y, Wang HL. Chronic Pb Exposure Induces Anxiety and Depression-like Behaviors in Mice via Excitatory Neuronal Hyperexcitability in Ventral Hippocampal Dentate Gyrus. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:12222-12233. [PMID: 37559393 DOI: 10.1021/acs.est.3c03426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/11/2023]
Abstract
Lead (Pb) is a widespread neurotoxic pollutant. Pb exposure is associated with mood disorders, with no well-established neural mechanisms elucidated. In the present study, we aimed to investigate whether excitatory neurons in the dentate gyrus subregion of the ventral hippocampus (vDG) played a key role in Pb-induced anxiety and depression-like behaviors. C57BL/6 mice were exposed to 100 ppm Pb starting on day 1 of pregnancy until experiments were performed using the offspring. Behavioral studies suggested that chronic Pb exposure triggered anxiety and depression-like behaviors. A combination of electrophysiological, optogenetic, and immunohistochemistry experiments was conducted. Results showed that Pb exposure resulted in excitatory neuronal hyperexcitability in vDG and that the behavioral deficits caused by Pb exposure could be rescued by inhibition of excitatory neuronal activity. Moreover, it was found that the action potential (AP) threshold of excitatory neurons was decreased by electrophysiological recordings. Our study demonstrates a significant role for excitatory neurons in vDG in Pb-induced anxiety and depression-like behaviors in mice, which is likely a result of decreased AP threshold. These outcomes can serve as an important basis for understanding mechanisms of anxiety and depression under environmental Pb exposure and help in the design of therapeutic strategies.
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Affiliation(s)
- Ruiqing Zhou
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230000, Anhui, PR China
| | - Chengqing Huang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230000, Anhui, PR China
| | - Nanxi Bi
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230000, Anhui, PR China
| | - Ling Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230000, Anhui, PR China
| | - Changqing Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230000, Anhui, PR China
| | - Xiaozhen Gu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230000, Anhui, PR China
| | - Yang Song
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, PR China
| | - Hui-Li Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei 230000, Anhui, PR China
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Liu M, Liu R, Yang M, Ba Y, Deng Q, Zhang Y, Han L, Gao L, Huang H. Combined exposure to lead and high-fat diet induced neuronal deficits in rats: Anti-neuroinflammatory role of SIRT1. Food Chem Toxicol 2023; 177:113857. [PMID: 37244597 DOI: 10.1016/j.fct.2023.113857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/19/2023] [Accepted: 05/23/2023] [Indexed: 05/29/2023]
Abstract
INTRODUCTION Lead (Pb) exposure and high-fat diet (HFD) trigger neurotoxicity, which may involve neuroinflammation. However, the mechanism by which combined Pb and HFD exposure induces nucleotide oligomerization domain-like receptor family pyrin domain 3 (NLRP3) inflammasome activation has not been fully elucidated. MATERIAL AND METHODS The Sprague-Dawley (SD) rat model of exposure to Pb and HFD was established to reveal the influence of co-exposure on cognition and identify signaling clues that mediate neuroinflammation and synaptic dysregulation. PC12 cells was treated with Pb and PA in vitro. Silent information regulator 1 (SIRT1) agonist (SRT 1720) was employed as intervention agent. RESULTS Our results showed that Pb and HFD exposure induced cognitive impairment and lead to neurological damage in rats. Meanwhile, Pb and HFD could stimulate the NLRP3 inflammasome assembly and activate caspase 1, releasing proinflammatory cytokines interleukin-1β (IL-1β) and interleukin-18 (IL-18), further promoting neuronal cell activation and amplifying neuroinflammatory responses. Additionally, our findings suggest that SIRT1 plays a role in Pb and HFD induced neuroinflammation. However, the use of SRT 1720 agonists showed some potential in alleviating these impairments. CONCLUSION Pb exposure and HFD intake could induce neuronal damage through activation of the NLRP3 inflammasome pathway and synaptic dysregulation, while the NLRP3 inflammasome pathway may be rescued via activating SIRT1.
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Affiliation(s)
- Mengchen Liu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China.
| | - Rundong Liu
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China.
| | - Mingzhi Yang
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China.
| | - Yue Ba
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China.
| | - Qihong Deng
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China.
| | - Yu Zhang
- State Key Laboratory of Microbial Technology, Qingdao, Shandong, 266000, China; Shandong Engineering Research Center of Biomarker and Artificial Intelligence Application, Jinan, Shandong, 250100, China; Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong, 266000, China.
| | - Lin Han
- Shandong Engineering Research Center of Biomarker and Artificial Intelligence Application, Jinan, Shandong, 250100, China; Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong, 266000, China.
| | - Lihua Gao
- Zhengzhou Center for Disease Control and Prevention, Zhengzhou, Henan, 450052, China.
| | - Hui Huang
- Department of Environmental Health, College of Public Health, Zhengzhou University, Zhengzhou, Henan province, 450001, China.
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Ai S, Li D, Gu X, Xu Y, Wang Y, Wang HL, Chen XT. Profile of N6-methyladenosine of Pb-exposed neurons presents epitranscriptomic alterations in PI3K-AKT pathway-associated genes. Food Chem Toxicol 2023:113821. [PMID: 37269892 DOI: 10.1016/j.fct.2023.113821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 04/21/2023] [Accepted: 05/08/2023] [Indexed: 06/05/2023]
Abstract
Lead (Pb) is a pervasive heavy metal with multi-organ toxicity. However, the molecular mechanisms of Pb-induced neurotoxicity are not fully understood. The dynamics of N6-methylademine (m6A) is an emerging regulatory mechanism for gene expression, which is closely related to nervous system diseases. To elucidate the association between m6A modification and Pb-mediated neurotoxicity, primary hippocampal neurons exposed to 5 μM Pb for 48 h were used as the paradigm neurotoxic model in this study. According to the results, Pb exposure reprogrammed the transcription spectrum. Simultaneously, Pb exposure remodeled the transcriptome-wide distribution of m6A while disrupting the overall level of m6A in cellular transcripts. United analysis of MeRIP-Seq and RNA-Seq was applied to further identify the core genes whose expression levels are regulated by m6A in the process of lead-induced nerve injury. GO and KEGG analysis unveiled that the modified transcripts were overrepresented by the PI3K-AKT pathway. Mechanically, we elucidated the regulatory role of the methyltransferase like3 (METTL3) in the process of lead-induced neurotoxicity and the downregulation of the PI3K-AKT pathway. In conclusion, our novel findings shed new light on the functional roles of m6A modification in the expressional alternations of downstream transcripts caused by lead, providing an innovative molecular basis to explain Pb neurotoxicity.
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Affiliation(s)
- Shu Ai
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Danyang Li
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Xiaozhen Gu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Yi Xu
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China
| | - Yi Wang
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, PR China
| | - Hui-Li Wang
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, Anhui, PR China.
| | - Xiang-Tao Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui, PR China.
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Liu H, Zhou R, Yin L, Si N, Yang C, Huang C, Wang R, Chen X. β-asarone prolongs sleep via regulating the level of glutamate in the PVN. Biochem Biophys Res Commun 2023; 665:71-77. [PMID: 37149985 DOI: 10.1016/j.bbrc.2023.05.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 04/20/2023] [Accepted: 05/02/2023] [Indexed: 05/09/2023]
Abstract
People of all ages could suffer from sleep disorders, which are increasingly recognized as common manifestations of neurologic disease. Acorus tatarinowii is a herb that has been used in traditional medicine to promote sleep. β-asarone, as the main component of volatile oil obtained from Acorus tatarinowii, may be the main contributor to the sleeping-promoting efficacy of Acorus tatarinowii. In the study, adult male C57BL/6 mice were administered β-asarone at 12.5 mg/kg, 25 mg/kg, and 50 mg/kg. Behavioral experiments showed that β-asarone at 25 mg/kg could significantly improve sleep duration. It was also observed that the proportion of NREM (Non-Rapid Eye Movement) sleep increased considerably after administration of β-asarone. In the PVN (paraventricular nucleus of hypothalamus) region of the hypothalamus, it was observed that the glutamate content decreased after β-asarone treatment. At the same time, the expression of VGLUT2 (vesicular glutamate transporters 2) decreased while the expression of GAD65 (glutamic acid decarboxylase 65) and GABARAP (GABA Type A Receptor-Associated Protein) increased in the hypothalamus, suggesting that β-asarone may suppress arousal by reducing glutamate and promoting transformation of glutamate to the inhibitory neurotransmitter GABA (γ-aminobutyric acid). This study is the first to focus on the association between β-asarone and sleep, shedding perspectives for pharmacological applications of β-asarone and providing a new direction for future research.
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Affiliation(s)
- Haoyu Liu
- School of Pharmacy, Anhui Medical University, Hefei, 230032, China
| | - Ruiqing Zhou
- School of Food Science and Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Lanxiang Yin
- School of Pharmacy, Anhui Medical University, Hefei, 230032, China
| | - Nana Si
- School of Pharmacy, Anhui Medical University, Hefei, 230032, China
| | - Chenglin Yang
- School of Pharmacy, Anhui Medical University, Hefei, 230032, China
| | - Chengqing Huang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Rongrong Wang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, 230009, China
| | - Xiangtao Chen
- School of Pharmacy, Anhui Medical University, Hefei, 230032, China.
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Wang T, Guan RL, Zou YF, Zheng G, Shen XF, Cao ZP, Yang RH, Liu MC, Du KJ, Li XH, Aschner M, Zhao MG, Chen JY, Luo WJ. MiR-130/SNAP-25 axis regulate presynaptic alteration in anterior cingulate cortex involved in lead induced attention deficits. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130249. [PMID: 36332276 DOI: 10.1016/j.jhazmat.2022.130249] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 10/18/2022] [Accepted: 10/21/2022] [Indexed: 06/16/2023]
Abstract
Brain volume decrease in the anterior cingulate cortex (ACC) after lead (Pb) exposure has been linked to persistent impairment of attention behavior. However, the precise structural change and molecular mechanism for the Pb-induced ACC alteration and its contribution to inattention have yet to be fully characterized. The present study determined the role of miRNA regulated synaptic structural and functional impairment in the ACC and its relationship to attention deficit disorder in Pb exposed mice. Results showed that Pb exposure induced presynaptic impairment and structural alterations in the ACC. Furthermore, we screened for critical miRNA targets responsible for the synaptic alteration. We found that miR-130, which regulates presynaptic vesicle releasing protein SNAP-25, was responsible for the presynaptic impairment in the ACC and attention deficits in mice. Blocking miR-130 function reversed the Pb-induced decrease in the expression of its presynaptic target SNAP-25, leading to the redistribution of presynaptic vesicles, as well as improved presynaptic function and attention in Pb exposed mice. We report, for the first time, that miR-130 regulating SNAP-25 mediates Pb-induced presynaptic structural and functional impairment in the ACC along with attention deficit disorder in mice.
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Affiliation(s)
- Tao Wang
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China.
| | - Rui-Li Guan
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Yun-Feng Zou
- Department of Toxicology, School of Public Health, Guangxi Medical University, Nanning 530021, China
| | - Gang Zheng
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Xue-Feng Shen
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Zi-Peng Cao
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Rui-Hua Yang
- Department of Nutrition & Food Hygiene and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Ming-Chao Liu
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Ke-Jun Du
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Xue-Hang Li
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Ming-Gao Zhao
- Precision Pharmacy & Drug Development Center, Department of Pharmacy, Tangdu Hospital, Fourth Military Medical University, Xi'an 710032, China.
| | - Jing Yuan Chen
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China.
| | - Wen-Jing Luo
- Department of Occupational & Environmental Health and the Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment, School of Public Health, Fourth Military Medical University, Xi'an 710032, China.
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Li Z, He Z, Li Z, Sun T, Zhang W, Xiang H. Differential synaptic mechanism underlying the neuronal modulation of prefrontal cortex, amygdala, and hippocampus in response to chronic postsurgical pain with or without cognitive deficits in rats. Front Mol Neurosci 2022; 15:961995. [PMID: 36117908 PMCID: PMC9478413 DOI: 10.3389/fnmol.2022.961995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 08/12/2022] [Indexed: 11/15/2022] Open
Abstract
Chronic Postsurgical Pain (CPSP) is well recognized to impair cognition, particularly memory. Mounting evidence suggests anatomic and mechanistic overlap between pain and cognition on several levels. Interestingly, the drugs currently used for treating chronic pain, including opioids, gabapentin, and NMDAR (N-methyl-D-aspartate receptor) antagonists, are also known to impair cognition. So whether pain-related cognitive deficits have different synaptic mechanisms as those underlying pain remains to be elucidated. In this context, the synaptic transmission in the unsusceptible group (cognitively normal pain rats) was isolated from that in the susceptible group (cognitively compromised pain rats). It was revealed that nearly two-thirds of the CPSP rats suffered cognitive impairment. The whole-cell voltage-clamp recordings revealed that the neuronal excitability and synaptic transmission in the prefrontal cortex and amygdala neurons were enhanced in the unsusceptible group, while these parameters remained the same in the susceptible group. Moreover, the neuronal excitability and synaptic transmission in hippocampus neurons demonstrated the opposite trend. Correspondingly, the levels of synaptic transmission-related proteins demonstrated a tendency similar to that of the excitatory and inhibitory synaptic transmission. Furthermore, morphologically, the synapse ultrastructure varied in the postsynaptic density (PSD) between the CPSP rats with and without cognitive deficits. Together, these observations indicated that basal excitatory and inhibitory synaptic transmission changes were strikingly different between the CPSP rats with and without cognitive deficits.
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Chen L, Liu Y, Jia P, Zhang H, Yin Z, Hu D, Ning H, Ge Y. Acute lead acetate induces neurotoxicity through decreased synaptic plasticity-related protein expression and disordered dendritic formation in nerve cells. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:58927-58935. [PMID: 35377123 DOI: 10.1007/s11356-022-20051-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/29/2022] [Indexed: 06/14/2023]
Abstract
Lead (Pb) is a widespread environmental heavy metal that can damage the cerebral cortex and hippocampus, and reduce the learning and memory ability in humans and animals. In vivo and in vitro models of acute lead acetate exposure were established to further study the mechanism of neurons injury. In this study, 4-week-old female Kunming mice were randomly divided into four groups. Each group was treated with distilled water with different Pb concentrations (0, 2.4, 4.8 and 9.6 mM). Mice were killed, and brain tissues were collected to detect the changes in synaptic plasticity-related protein expression. Furthermore, Neuro-2A cells were treated with 0, 5, 25 and 50 μM lead acetate for 24 h to observe the changes in cell morphology and function. In in vivo experiment, results showed that the expression levels of cytoskeleton-associated and neural function-related proteins decreased in a dose-dependent manner in the mouse brain tissue. In in vitro experiment, compared with the control group, Pb treatment groups were observed with smaller and round cells, decreased cell density and number of synapses. In the Pb exposure group, the survival rate of nerve cells decreased evidently, and the permeability of the cell membrane was increased. Western blot results showed that the expression of cytoskeleton-associated and function-related proteins decreased gradually with increased Pb exposure dose. Confocal laser scanning microscopy results revealed the morphological and volumetric changes in Neuro-2A cells, and a dose-dependent reduction in the number of axon and dendrites. These results suggested that abnormal neural structures and inhibiting expression of synaptic plasticity-related proteins might be the possible mechanisms of Pb-induced mental retardation in human and animals, thereby laying a foundation for the molecular mechanism of Pb neurotoxicity.
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Affiliation(s)
- Lingli Chen
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China
- Postdoctoral Research and Development Base, Henan Institute of Science and Technology, Xinxiang, Henan, People's Republic of China
| | - Yuye Liu
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China
| | - Penghuan Jia
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China
| | - Hongli Zhang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China
| | - Zhihong Yin
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China
- Postdoctoral Research and Development Base, Henan Institute of Science and Technology, Xinxiang, Henan, People's Republic of China
| | - Dongfang Hu
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China
- Postdoctoral Research and Development Base, Henan Institute of Science and Technology, Xinxiang, Henan, People's Republic of China
| | - Hongmei Ning
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China
| | - Yaming Ge
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, Henan, 453003, People's Republic of China.
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11
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Li Z, Sun T, He Z, Li Z, Zhang W, Wang J, Xiang H. SCFAs Ameliorate Chronic Postsurgical Pain-Related Cognition Dysfunction via the ACSS2-HDAC2 Axis in Rats. Mol Neurobiol 2022; 59:6211-6227. [PMID: 35902549 PMCID: PMC9463230 DOI: 10.1007/s12035-022-02971-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 07/20/2022] [Indexed: 11/25/2022]
Abstract
Patients with chronic postsurgical pain (CPSP) frequently exhibit comorbid cognitive deficits. Recent observations have emphasized the critical effects of gut microbial metabolites, like short-chain fatty acids (SCFAs), in regulating cognitive function. However, the underlying mechanisms and effective interventions remain unclear. According to hierarchical clustering and 16S rRNA analysis, over two-thirds of the CPSP rats had cognitive impairment, and the CPSP rats with cognitive impairment had an aberrant composition of gut SCFA-producing bacteria. Then, using feces microbiota transplantation, researchers identified a causal relationship between cognitive-behavioral and microbic changes. Similarly, the number of genera that generated SCFAs was decreased in the feces from recipients of cognitive impairment microbiota. Moreover, treatment with the SCFAs alleviated the cognitive-behavioral deficits in the cognitively compromised pain rats. Finally, we observed that SCFA supplementation improved histone acetylation and abnormal synaptic transmission in the medial prefrontal cortex (mPFC), hippocampal CA1, and central amygdala (CeA) area via the ACSS2 (acetyl-CoA synthetase2)-HDAC2 (histone deacetylase 2) axis. These findings link pain-related cognition dysfunction, gut microbiota, and short-chain fatty acids, shedding fresh insight into the pathogenesis and therapy of pain-associated cognition dysfunction.
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Affiliation(s)
- Zhen Li
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Tianning Sun
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Zhigang He
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Zhixiao Li
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Wencui Zhang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China
| | - Jie Wang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences-Wuhan National Laboratory for Optoelectronics, Wuhan, 430071, Hubei, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Hongbing Xiang
- Department of Anesthesiology and Pain Medicine, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, China.
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12
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Gu X, Bi N, Wang T, Huang C, Wang R, Xu Y, Wang HL. Probiotic Lactobacillus rhamnosus GR-1 supplementation attenuates Pb-induced learning and memory deficits by reshaping the gut microbiota. Front Nutr 2022; 9:934118. [PMID: 35928850 PMCID: PMC9344877 DOI: 10.3389/fnut.2022.934118] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/27/2022] [Indexed: 12/20/2022] Open
Abstract
Lead (Pb) exposure during early life has been associated with an increased risk of neurodevelopmental disorders, including learning and memory deficits. The intestinal flora, via the microbiome–gut–brain axis, could play a significant role in the nervous system. However, the effects of probiotics on ameliorating Pb-induced learning and memory deficits are still unclear. In this study, we showed that adolescent Pb exposure (150 ppm) for 2 months impaired spatial learning and memory ability, accompanied by the decreasing diversity of gut microbiota, and the decreasing abundance of Lactobacillus at the genus level. Surprisingly, administration of the Lactobacillus rhamnosus GR-1 (1010 organisms/rat/day), not L. rhamnosus LGG or Lactobacillus reuteri RC-14, reversed learning and memory deficits induced by Pb exposure. Meanwhile, administration of the L. rhamnosus GR-1 increased the diversity of the gut microbiota composition and partially normalized the genus level of Lactobacillus, Parabacteroides, Enterococcus, and Akkermansia in Pb-exposed rats. Notably, supplementation of L. rhamnosus GR-1 decreased the gut permeability of Pb-exposed rats, reduced proinflammatory cytokines [interleukin-1β (IL-1β) and IL-6] expression, and promoted anti-inflammatory cytokines [granulocyte colony-stimulating factor (G-CSF)] expression. Interestingly, neural cell treatment with G-CSF rescued Pb-induced neurotoxicity. In general, L. rhamnosus GR-1 supplementation recovered the Pb-induced loss of intestinal bacteria (Lactobacillus), which may have reversed the damage to learning and memory ability. Collectively, our findings demonstrate an unexpectedly pivotal role of L. rhamnosus GR-1 in Pb-induced cognitive deficits and identify a potential probiotic therapy for cognitive dysfunction during early life.
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Affiliation(s)
- Xiaozhen Gu
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, China
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Nanxi Bi
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, China
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Tian Wang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, China
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Chengqing Huang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, China
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Rongrong Wang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, China
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
| | - Yi Xu
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, China
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
- *Correspondence: Yi Xu,
| | - Hui-Li Wang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, Hefei, China
- School of Food and Biological Engineering, Hefei University of Technology, Hefei, China
- Hui-Li Wang,
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13
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Abstract
Lead (Pb2+) is a non-essential metal with numerous industrial applications that have led to ts ubiquity in the environment. Thus, not only occupational-exposed individuals' health is compromised, but also that of the general population and in particular children. Notably, although the central nervous system is particularly susceptible to Pb2+, other systems are affected as well. The present study focuses on molecular mechanisms that underlie the effects that arise from the presence of Pb2+ in situ in the brain, and the possible toxic effects that follows. As the brain barriers represent the first target of systemic Pb2+, mechanisms of Pb2+ entry into the brain are discussed, followed by a detailed discussion on neurotoxic mechanisms, with special emphasis on theories of ion mimicry, mitochondrial dysfunction, redox imbalance, and neuroinflammation. Most importantly, the confluence and crosstalk between these events is combined into a cogent mechanism of toxicity, by intertwining recent and old evidences from humans, in vitro cell culture and experimental animals. Finally, pharmacological interventions, including chelators, antioxidants substances, anti-inflammatory drugs, or their combination are reviewed as integrated approaches to ameliorate Pb2+ harmful effects in both developing or adult organisms.
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Affiliation(s)
- Miriam B. Virgolini
- IFEC CONICET. IFEC-CONICET. Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba. Haya de la Torre y Medina Allende, Ciudad Universitaria, 5016, Córdoba, Argentina
| | - Michael Aschner
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, Bronx, NY, USA and IM Sechenov First Moscow State Medical University (Sechenov University), 119146, Moscow, Russia
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14
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Gu X, Huang X, Li D, Bi N, Yu X, Wang HL. Nuclear accumulation of histone deacetylase 4 (HDAC4) by PP1-mediated dephosphorylation exerts neurotoxicity in Pb-exposed neural cells. Neurotoxicology 2020; 81:395-405. [PMID: 33080273 DOI: 10.1016/j.neuro.2020.10.006] [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: 05/12/2020] [Revised: 10/13/2020] [Accepted: 10/13/2020] [Indexed: 10/23/2022]
Abstract
Lead (Pb) is an environmental contaminant that primarily affects the central nervous system, particularly the developing brain. Recently, increasing evidence indicates the important roles of histone deacetylases (HDACs) in Pb-induced neurotoxicity. However, the precise molecular mechanisms involving HDAC4 remains unknown. The purpose of this study was to investigate the role of HDAC4 in Pb-induced neurotoxicity both in vivo and in vitro. In vitro study, PC12 cells were exposed to Pb (10 μM) for 24 h, then the mRNA and protein levels of HDAC4 were analyzed. In vivo study, pregnant rats and their female offspring were treated with lead (50 ppm) until postnatal day 30. Then the pups were sacrificed and the mRNA and protein levels of HDAC4 in the hippocampus were analyzed. The results showed that HDAC4 was significantly increased in both PC12 cells and rat hippocampus upon Pb exposure. Blockade of HDAC4 with either LMK-235 (an inhibitor of HDAC4) or shHDAC4 (HDAC4-knocking down plasmid) ameliorated the Pb-induced neurite outgrowth deficits. Interestingly, HDAC4 was aberrantly accumulated in the nucleus upon Pb exposure. By contrast, blocking the HDAC4 shuffling from the cytosol to the nucleus with ΔNLS2-HDAC4 (the cytosol-localized HDAC4 mutant) was able to rescue the neuronal impairment. In addition, Pb increased PP1 (protein phosphatase 1) expression which in turn influenced the subcellular localization of HDAC4 by dephosphorylation of specific serine/threonine residues. What's more, blockade of PP1 with PP1-knocking down construct (shPP1) ameliorated Pb-induced neurite outgrowth deficits. Taken together, nuclear accumulation of HDAC4 by PP1-mediated dephosphorylation involved in Pb-induced neurotoxicity. This study might provide a promising molecular target for medical intervention with environmental cues.
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Affiliation(s)
- Xiaozhen Gu
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Xiyao Huang
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Danyang Li
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Nanxi Bi
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Xi Yu
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China
| | - Hui-Li Wang
- School of Food and Biological Engineering, Hefei University of Technology, No. 193 of Tunxi Road, Baohe District, 230009, Hefei, China.
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15
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Xiao B, Han F, Shi Y. Administration of moclobemide facilitates fear extinction and attenuates anxiety-like behaviors by regulating synaptic-associated proteins in a rat model of post-traumatic stress disorder. Synapse 2020; 74:e22146. [PMID: 31869485 DOI: 10.1002/syn.22146] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 12/15/2019] [Accepted: 12/17/2019] [Indexed: 12/21/2022]
Abstract
Post-traumatic stress disorder (PTSD) is a long-lasting mental disorder and accompanied by worse fear extinction. Enhanced fear memory or poor fear extinction are typical features of PTSD. Dysfunction of the serotonergic neurotransmitter system is involved in numerous mental and behavioral disorders. Monoamine oxidase A (MAOA) is important in the metabolism of serotonin and play an important role in behavious. The aim of this study was to explore the change of MAOA and effect of MAOA on fear memory in PTSD. We used single prolonged stress (SPS) to create animal model of PTSD. A startle/fear box and elevated plus maze were used to observe fear memory and anxiety level, respectively. We examined the expression of MAOA and synaptic marker protein, as well as the immunological activity of MAOA in the infralimbic cortex (IL) area, which is a critical brain region involved in emotions, especially fear regulation. We found increased anxiety-like behavior, dysfunction in fear extinction, and increased MAOA in SPS rats. After treatment with moclobemide (a selective inhibitor of MAOA), SPS rats showed significantly improved fear memory and decreased anxiety-like behavior, which indicated that moclobemide could reverse fear extinction deficit and attenuate abnormally increased levels of anxiety caused by SPS in short term. On the contrary, decreased PSD-95 and SYN1 expression in the IL region were also reversed by moclobemide. These results suggest that increased MAOA play a negative role in fear extinction and levels of anxiety in PTSD, which may be involved in change in PSD-95 and SYN1.
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Affiliation(s)
- Bing Xiao
- Basic Medical Sciences College, China Medical University, Shenyang, China
| | - Fang Han
- Basic Medical Sciences College, China Medical University, Shenyang, China
| | - Yuxiu Shi
- Basic Medical Sciences College, China Medical University, Shenyang, China
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16
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Zou RX, Gu X, Ding JJ, Wang T, Bi N, Niu K, Ge M, Chen XT, Wang HL. Pb exposure induces an imbalance of excitatory and inhibitory synaptic transmission in cultured rat hippocampal neurons. Toxicol In Vitro 2019; 63:104742. [PMID: 31785328 DOI: 10.1016/j.tiv.2019.104742] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 11/12/2019] [Accepted: 11/24/2019] [Indexed: 12/16/2022]
Abstract
An appropriate balance of excitatory and inhibitory synapse maintains the network stability of the central nervous system. Our recent work showed lead (Pb) exposure can inhibit synaptic transmission in cultured hippocampal neurons. However, it is not clear whether Pb exposure disrupt the balance of excitatory and inhibitory synaptic transmission. Here, primary cultured hippocampal neurons from Sprague-Dawley (SD) rats were exposed to Pb (0.2 μM, 1 μM, 5 μM, respectively) from Days in Vitro (DIV) 7 to DIV 12 for 5 days and the excitatory and inhibitory synaptic transmission was examined. Patch clamp recording results showed that distinct from exposures of 0.2 μM and 5 μM, 1 μM Pb exposure significantly increased the mIPSC frequency and decreased the mEPSC frequency, leading to a uniform inhibitory outcome. Further, the number of inhibitory presynaptic puncta was significantly increased after 1 μM Pb exposure, while the number of excitatory presynaptic terminals was decreased. In addition 1 μM Pb increased the glutamic acid decarboxylase (GAD65) expression and the surface GABAA receptor (GABAAR) clusters. This shift might potentiate the synthesis of GABA and enhance the surface distribution of postsynaptic GABAAR clusters in hippocampus neurons. Together, these data showed that Pb exposure disrupted the balance of excitatory and inhibitory synaptic transmission via abnormal GABAergic neurotransmission.
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Affiliation(s)
- Rong-Xin Zou
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Xiaozhen Gu
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Jin-Jun Ding
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Tiandong Wang
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Nanxi Bi
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Kang Niu
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Mengmeng Ge
- School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China
| | - Xiang-Tao Chen
- School of Pharmacy, Anhui Medical University, Hefei, Anhui 230031, PR China.
| | - Hui-Li Wang
- Engineering Research Center of Bio-process, Ministry of Education, Hefei University of Technology, 193 Tunxi Road, Hefei, Anhui 230009, PR China; School of Food Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, PR China.
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17
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Gu X, Xu Y, Xue WZ, Wu Y, Ye Z, Xiao G, Wang HL. Interplay of miR-137 and EZH2 contributes to the genome-wide redistribution of H3K27me3 underlying the Pb-induced memory impairment. Cell Death Dis 2019; 10:671. [PMID: 31511494 PMCID: PMC6739382 DOI: 10.1038/s41419-019-1912-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2019] [Revised: 08/13/2019] [Accepted: 08/26/2019] [Indexed: 01/20/2023]
Abstract
Compromised learning and memory is a common feature of multiple neurodegenerative disorders. A paradigm spatial memory impairment could be caused by developmental lead (Pb) exposure. Growing evidence implicates epigenetic modifications in the Pb-mediated memory deficits; however, how histone modifications exemplified by H3K27me3 (H3 Lys27 trimethylation) contribute to this pathogenesis remains poorly understood. Here we found that Pb exposure diminished H3K27me3 levels in vivo by suppressing EZH2 (enhancer of zeste homolog 2) expression at an early stage. EZH2 overexpression in Pb-treated rats rescued the H3K27me3 abundance and partially restored the normal spatial memory, as manifested by the rat performance in a Morris water maze test, and structural analysis of hippocampal spine densities. Furthermore, miR-137 and EZH2 constitute mutually inhibitory loop to regulate the H3K27me3 level, and this feedback regulation could be specifically activated by Pb treatment. Considering genes targeted by H3K27me3, ChIP-chip (chromatin immunoprecipitation on chip) studies revealed that Pb could remodel the genome-wide distribution of H3K27me3, represented by pathways like transcriptional regulation, developmental regulation, cell motion, and apoptosis, as well as a novel Wnt9b locus. As a Wnt isoform associated with canonical and noncanonical signaling, Wnt9b was regulated by the opposite modifications of H3K4me3 (H3 Lys4 trimethylation) and H3K27me3 in Pb-exposed neurons. Rescue trials further validated the contribution of Wnt9b to Pb-induced neuronal impairments, wherein canonical or noncanonical Wnt signaling potentially exhibited destructive or protective roles, respectively. In summary, the study reveals an epigenetic-based molecular change underlying Pb-triggered spatial memory deficits, and provides new potential avenues for our understanding of neurodegenerative diseases with environmental etiology.
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Affiliation(s)
- Xiaozhen Gu
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Yi Xu
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Wei-Zhen Xue
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Yulan Wu
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China
| | - Zi Ye
- College of Life Science and Bio-engineering, Beijing University of Technology, Beijing, 100022, People's Republic of China
| | - Guiran Xiao
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China.
| | - Hui-Li Wang
- School of Food and Bioengineering, Hefei University of Technology, Hefei, Anhui, 230009, People's Republic of China.
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