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Wu X, Wu Y, Tang F, Wang Y, Li C, Wu S, Wang G, Zhang J. Foxq1 activates CB2R with oleamide to alleviate POCD. Brain Pathol 2024:e13289. [PMID: 39046224 DOI: 10.1111/bpa.13289] [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: 02/26/2024] [Accepted: 07/05/2024] [Indexed: 07/25/2024] Open
Abstract
Postoperative cognitive dysfunction (POCD) is a major concern, particularly among older adults. This study used social isolation (ISO) and multiomics analyses in aged mice to investigate potential mechanisms underlying POCD development. Aged mice were divided into two groups: ISO and paired housing (PH). Oleamide and the cannabinoid receptor type 2 (CB2R) antagonist AM630 were administered intraperitoneally, while Foxq1 adeno-associated viral (AAV) vector was injected directly into the hippocampus. Intramedullary tibial surgeries were subsequently performed to establish the POCD models. Behavioral tests comprising the Y-maze, open field test, and novel object recognition were conducted 2 days after surgery. Hippocampal and serum inflammatory cytokines were assessed. Following surgery, ISO mice demonstrated intensified cognitive impairments and escalated inflammatory markers. Integrative transcriptomic and metabolomic analysis revealed elevated oleamide concentrations in the hippocampus and serum of PH mice, with associative investigations indicating a close relationship between the Foxq1 gene and oleamide levels. While oleamide administration and Foxq1 gene overexpression substantially ameliorated postoperative cognitive performance and systemic inflammation in mice, CB2R antagonist AM630 impeded these enhancements. The Foxq1 gene and oleamide may be crucial in alleviating POCD. While potentially acting through CB2R-mediated pathways, these factors may modulate neuroinflammation and attenuate proinflammatory cytokine levels within the hippocampus, substantially improving cognitive performance postsurgery. This study lays the groundwork for future research into therapeutic approaches targeting the Foxq1-oleamide-CB2R axis, with the ultimate goal of preventing or mitigating POCD.
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Affiliation(s)
- Xiaoying Wu
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan, China
| | - Yuming Wu
- Department of Critical Care Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Fudong Tang
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan, China
| | - Yangyang Wang
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan, China
| | - Chenxi Li
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan, China
| | - Su Wu
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan, China
| | - Guangzhi Wang
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan, China
| | - Jiaqiang Zhang
- Department of Anesthesiology and Perioperative Medicine, People's Hospital of Zhengzhou University, Henan Provincial People's Hospital, Zhengzhou, Henan, China
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Sun J, Fleishman JS, Liu X, Wang H, Huo L. Targeting novel regulated cell death:Ferroptosis, pyroptosis, and autophagy in sepsis-associated encephalopathy. Biomed Pharmacother 2024; 174:116453. [PMID: 38513593 DOI: 10.1016/j.biopha.2024.116453] [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: 01/03/2024] [Revised: 03/04/2024] [Accepted: 03/15/2024] [Indexed: 03/23/2024] Open
Abstract
Sepsis-associated encephalopathy (SAE), a common neurological complication of sepsis, is a heterogenous complex clinical syndrome caused by the dysfunctional response of a host to infection. This dysfunctional response leads to excess mortality and morbidity worldwide. Despite clinical relevance with high incidence, there is a lack of understanding for its both its acute/chronic pathogenesis and therapeutic management. A better understanding of the molecular mechanisms behind SAE may provide tools to better enhance therapeutic efficacy. Mounting evidence indicates that some types of non-apoptotic regulated cell death (RCD), such as ferroptosis, pyroptosis, and autophagy, contribute to SAE. Targeting these types of RCD may provide meaningful targets for future treatments against SAE. This review summarizes the core mechanism by which non-apoptotic RCD leads to the pathogenesis of SAE. We focus on the emerging types of therapeutic compounds that can inhibit RCD and delineate their beneficial pharmacological effects against SAE. Within this review we suggest that pharmacological inhibition of non-apoptotic RCD may serve as a potential therapeutic strategy against SAE.
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Affiliation(s)
- Jingjing Sun
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang 11004, China
| | - Joshua S Fleishman
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, NY 11439, USA
| | - Xueyan Liu
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang 11004, China
| | - Hongquan Wang
- Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, 300060, China
| | - Liang Huo
- Department of Pediatrics, Shengjing Hospital of China Medical University, Shenyang 11004, China.
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Yu Z, Shi H, Zhang J, Ma C, He C, Yang F, Zhao L. ROLE OF MICROGLIA IN SEPSIS-ASSOCIATED ENCEPHALOPATHY PATHOGENESIS: AN UPDATE. Shock 2024; 61:498-508. [PMID: 38150368 DOI: 10.1097/shk.0000000000002296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
ABSTRACT Sepsis-associated encephalopathy (SAE) is a serious complication of sepsis, which is characterized by cognitive dysfunction, a poor prognosis, and high incidences of morbidity and mortality. Substantial levels of systemic inflammatory factors induce neuroinflammatory responses during sepsis, ultimately disrupting the central nervous system's (CNS) homeostasis. This disruption results in brain dysfunction through various underlying mechanisms, contributing further to SAE's development. Microglia, the most important macrophage in the CNS, can induce neuroinflammatory responses, brain tissue injury, and neuronal dysregulation, resulting in brain dysfunction. They serve an important regulatory role in CNS homeostasis and can be activated through multiple pathways. Consequently, activated microglia are involved in several pathogenic mechanisms related to SAE and play a crucial role in its development. This article discusses the role of microglia in neuroinflammation, dysfunction of neurotransmitters, disruption of the blood-brain barrier, abnormal control of cerebral blood flow, mitochondrial dysfunction, and reduction in the number of good bacteria in the gut as main pathogenic mechanisms of SAE and focuses on studies targeting microglia to ameliorate SAE to provide a theoretical basis for targeted microglial therapy for SAE.
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Affiliation(s)
| | - Hui Shi
- Department of Critical Care Medicine, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, China
| | - Jingjing Zhang
- Department of Central Laboratory, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, China
| | - Chunhan Ma
- Chifeng Clinical Medical College of Inner Mongolia Medical University, Hohhot, China
| | - Chen He
- Chifeng Clinical Medical College of Inner Mongolia Medical University, Hohhot, China
| | - Fei Yang
- Department of Critical Care Medicine, Chifeng Municipal Hospital, Chifeng Clinical Medical College of Inner Mongolia Medical University, Chifeng, China
| | - Lina Zhao
- Department of Critical Care Medicine, General Hospital of Tianjin Medical University, Tianjin, China
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Wang CM, Zhang Y, Yang YS, Lin S, He HF. Effect of esketamine pretreatment on acute sepsis-associated encephalopathy. Exp Neurol 2024; 372:114646. [PMID: 38070725 DOI: 10.1016/j.expneurol.2023.114646] [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: 08/27/2023] [Revised: 11/12/2023] [Accepted: 12/03/2023] [Indexed: 12/17/2023]
Abstract
PURPOSE Esketamine, the S(+) enantiomer of ketamine, exhibits good anesthetic efficacy and controllability; however, its potential clinical applications, particularly in sepsis-associated encephalopathy (SAE), remain underexplored. SAE involves the development of diffuse brain dysfunction after sepsis, leading to markedly increased sepsis-related disability and mortality. In this study, we investigated the effects of esketamine pretreatment on acute SAE. METHODS Mice were randomly divided into four groups: control (C, n = 22), acute SAE (L, n = 22), esketamine pretreatment + acute SAE (EL, n = 22), and nuclear factor erythroid 2-related factor 2 (Nrf2) inhibitor (ML385) + esketamine pretreatment + acute SAE (N + EL, n = 22). Acute SAE was established using intraperitoneal (i.p.) injection of lipopolysaccharide (LPS; 10 mg/kg), while controls received equal amounts of saline. The EL group received daily i.p. injections of esketamine (10 mg/kg) for 5 consecutive days, followed by LPS on day 6. The N + EL group received i.p. injections of ML385 (30 mg/kg) 1 h before esketamine pretreatment. The remainder of treatment followed the same protocol as the EL group. Behavioral tests were performed 24 h post-LPS injection, and whole blood and brain tissues were collected for further analysis. RESULTS Esketamine improved sepsis symptoms, 7-day survival, and spatial cognitive impairment, without altering locomotor activity. Moreover, esketamine reversed the LPS-induced increase in serum S100 calcium-binding protein β and neuron-specific enolase levels and reduced hippocampal neuroinflammation, oxidative stress, and neuronal apoptosis in the EL group. However, these neuroprotective effects of esketamine were reversed by ML385. CONCLUSION The results of our study suggest that esketamine pretreatment mitigates acute SAE, highlighting the involvement of the Nrf2/heme oxygenase-1 pathway in mediating its neuroprotective effects.
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Affiliation(s)
- Cong-Mei Wang
- Department of Anesthesiology, Shishi General Hospital, Fujian Province, China
| | - Yan Zhang
- Department of Anesthesiology, Zhuzhou Central Hospital, Hunan Province, China
| | - Yu-Shen Yang
- Department of Anesthesiology, the Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian Province, China
| | - Shu Lin
- Department of Anesthesiology, the Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian Province, China; Group of Neuroendocrinology, Garvan Institute of Medical Research, 384 Victoria St, Sydney, Australia; Center of Neurological and Metabolic Research, the Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian Province, China
| | - He-Fan He
- Department of Anesthesiology, the Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian Province, China.
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Hu J, Xie S, Zhang H, Wang X, Meng B, Zhang L. Microglial Activation: Key Players in Sepsis-Associated Encephalopathy. Brain Sci 2023; 13:1453. [PMID: 37891821 PMCID: PMC10605398 DOI: 10.3390/brainsci13101453] [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: 08/20/2023] [Revised: 10/03/2023] [Accepted: 10/11/2023] [Indexed: 10/29/2023] Open
Abstract
Sepsis-associated encephalopathy (SAE) is a common brain dysfunction, which results in severe cognitive and neurological sequelae and an increased mortality rate in patients with sepsis. Depending on the stimulus, microglia (resident macrophages in the brain that are involved in SAE pathology and physiology) can adopt two polarization states (M1/M2), corresponding to altered microglial morphology, gene expression, and function. We systematically described the pathogenesis, morphology, function, and phenotype of microglial activation in SAE and demonstrated that microglia are closely related to SAE occurrence and development, and concomitant cognitive impairment. Finally, some potential therapeutic approaches that can prime microglia and neuroinflammation toward the beneficial restorative microglial phenotype in SAE were outlined.
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Affiliation(s)
- Jiyun Hu
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Shucai Xie
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Haisong Zhang
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Xinrun Wang
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Binbin Meng
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
| | - Lina Zhang
- Department of Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- Hunan Provincial Clinical Research Center for Critical Care Medicine, Xiangya Hospital, Central South University, Changsha 410008, China
- National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Central South University, Changsha 410008, China
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Ji MH, Gao YZ, Shi CN, Wu XM, Yang JJ. Acute and long-term cognitive impairment following sepsis: mechanism and prevention. Expert Rev Neurother 2023; 23:931-943. [PMID: 37615511 DOI: 10.1080/14737175.2023.2250917] [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: 05/28/2023] [Accepted: 08/18/2023] [Indexed: 08/25/2023]
Abstract
INTRODUCTION Sepsis is a severe host response to infection, which induces both acute and long-term cognitive impairment. Despite its high incidence following sepsis, the underlying mechanisms remain elusive and effective treatments are not available clinically. AREA COVERED This review focuses on elucidating the pathological mechanisms underlying cognitive impairment following sepsis. Specifically, the authors discuss the role of systemic inflammation response, blood-brain barrier disruption, neuroinflammation, mitochondrial dysfunction, neuronal dysfunction, and Aβ accumulation and tau phosphorylation in cognitive impairment after sepsis. Additionally, they review current strategies to ameliorate cognitive impairment. EXPERT OPINION Potential interventions to reduce cognitive impairment after sepsis include earlier diagnosis and effective infection control, hemodynamic homeostasis, and adequate brain perfusion. Furthermore, interventions to reduce inflammatory response, reactive oxygen species, blood-brain barrier disruption, mitochondrial dysfunction, neuronal injury or death could be beneficial. Implementing strategies to minimize delirium, sleep disturbance, stress factors, and immobility are also recommended. Furthermore, avoiding neurotoxins and implementing early rehabilitation may also be important for preventing cognitive impairment after sepsis.
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Affiliation(s)
- Mu-Huo Ji
- Department of Anesthesiology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Yu-Zhu Gao
- Department of Anesthesiology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Cui-Na Shi
- Department of Anesthesiology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Xin-Miao Wu
- Department of Anesthesiology, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, China
| | - Jian-Jun Yang
- Department of Anesthesiology, Pain and Perioperative Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Yang X, Tang Z. The role of pyroptosis in cognitive impairment. Front Neurosci 2023; 17:1206948. [PMID: 37332874 PMCID: PMC10272378 DOI: 10.3389/fnins.2023.1206948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 05/18/2023] [Indexed: 06/20/2023] Open
Abstract
Cognitive impairment is a major global disease, manifests as a decline in cognitive functioning and endangers the health of the population worldwide. The incidence of cognitive impairment has increased rapidly with an increasingly aging population. Although the mechanisms of cognitive impairment have partly been elucidated with the development of molecular biological technology, treatment methods are very limited. As a unique form of programmed cell death, pyroptosis is highly pro-inflammatory and is closely associated with the incidence and progression of cognitive impairment. In this review, we discuss the molecular mechanisms of pyroptosis briefly and the research progress on the relationship between pyroptosis and cognitive impairment and its potential therapeutic values, to provide a reference for research in the field of cognitive impairment.
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Affiliation(s)
- Xin Yang
- Department of Oncology, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhe Tang
- Department of Thoracic Surgery, Tongji Hospital of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Grabon W, Rheims S, Smith J, Bodennec J, Belmeguenai A, Bezin L. CB2 receptor in the CNS: from immune and neuronal modulation to behavior. Neurosci Biobehav Rev 2023; 150:105226. [PMID: 37164044 DOI: 10.1016/j.neubiorev.2023.105226] [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: 12/30/2022] [Revised: 03/20/2023] [Accepted: 05/06/2023] [Indexed: 05/12/2023]
Abstract
Despite low levels of cannabinoid receptor type 2 (CB2R) expression in the central nervous system in human and rodents, a growing body of evidence shows CB2R involvement in many processes at the behavioral level, through both immune and neuronal modulations. Recent in vitro and in vivo evidence have highlighted the complex role of CB2R under physiological and inflammatory conditions. Under neuroinflammatory states, its activation seems to protect the brain and its functions, making it a promising target in a wide range of neurological disorders. Here, we provide a complete and updated overview of CB2R function in the central nervous system of rodents, spanning from modulation of immune function in microglia but also in other cell types, to behavior and neuronal activity, in both physiological and neuroinflammatory contexts.
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Affiliation(s)
- Wanda Grabon
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France.
| | - Sylvain Rheims
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France; Department of Functional Neurology and Epileptology, Hospices Civils de Lyon - France
| | - Jonathon Smith
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France
| | - Jacques Bodennec
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France
| | - Amor Belmeguenai
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France; Epilepsy Institute IDEE, 59 boulevard Pinel - F-69500 Bron, France
| | - Laurent Bezin
- Université Claude Bernard Lyon 1, CNRS, Inserm, Centre de Recherche en Neurosciences de Lyon, U10208 UMR5292, TIGER Team - F-69500 Bron, France.
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CB2R activation ameliorates late adolescent chronic alcohol exposure-induced anxiety-like behaviors during withdrawal by preventing morphological changes and suppressing NLRP3 inflammasome activation in prefrontal cortex microglia in mice. Brain Behav Immun 2023; 110:60-79. [PMID: 36754245 DOI: 10.1016/j.bbi.2023.02.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 01/08/2023] [Accepted: 02/03/2023] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Chronic alcohol exposure (CAE) during late adolescence increases the risk of anxiety development. Alcohol-induced prefrontal cortex (PFC) microglial activation, characterized by morphological changes and increased associations with neurons, plays a critical role in the pathogenesis of anxiety. Alcohol exposure increases NLRP3 inflammasome expression, increasing cytokine secretion by activated microglia. Cannabinoid type 2 receptor (CB2R), an essential receptor of the endocannabinoid system, regulates microglial activation and neuroinflammatory reactions. We aimed to investigate the role of CB2R activation in ameliorating late adolescent CAE-induced anxiety-like behaviors and microglial activation in C57BL/6J mice. METHODS Six-week-old C57BL/6J mice were acclimated for 7 days and then were administered alcohol by gavage (4 g/kg, 25 % w/v) for 28 days. The mice were intraperitoneally injected with the specific CB2R agonist AM1241 1 h before alcohol treatment. Anxiety-like behaviors during withdrawal were assessed by open field test and elevated plus maze test 24 h after the last alcohol administration. Microglial activation, microglia-neuron interactions, and CB2R and NLRP3 inflammasome-related molecule expression in the PFC were measured using immunofluorescence, immunohistochemical, qPCR, and Western blotting assays. Microglial morphology was evaluated by Sholl analysis and the cell body-to-total cell size index. Additionally, N9 microglia were activated by LPS in vitro, and the effects of AM1241 on NLRP3 and N9 microglial activation were investigated. RESULTS After CAE, mice exhibited severe anxiety-like behaviors during withdrawal. CAE induced obvious microglia-neuron associations, and increased expression of microglial activation markers, CB2R, and NLRP3 inflammasome-related molecules in the PFC. Microglia also showed marked filament retraction and reduction and cell body enlargement after CAE. AM1241 treatment ameliorated anxiety-like behaviors in CAE model mice, and it prevented microglial morphological changes, reduced microglial activation marker expression, and suppressed the microglial NLRP3 inflammasome activation and proinflammatory cytokine secretion induced by CAE. AM1241 suppressed the LPS-induced increase in NLRP3 inflammasome-related molecules, IL-1β release, and M1 phenotype markers (iNOS and CD86) in N9 cell, which was reversed by CB2R antagonist treatment. CONCLUSIONS CAE caused anxiety-like behaviors in late adolescent mice at least partly by inducing microglial activation and increasing microglia-neuron associations in the PFC. CB2R activation ameliorated these effects by preventing morphological changes and suppressing NLRP3 inflammasome activation in PFC microglia.
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Oleamide Reduces Mitochondrial Dysfunction and Toxicity in Rat Cortical Slices Through the Combined Action of Cannabinoid Receptors Activation and Induction of Antioxidant Activity. Neurotox Res 2022; 40:2167-2178. [PMID: 36069981 DOI: 10.1007/s12640-022-00575-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 08/12/2022] [Accepted: 08/30/2022] [Indexed: 12/31/2022]
Abstract
The potential treatment of neurodegenerative disorders requires the development of novel pharmacological strategies at the experimental level, such as the endocannabinoid-based therapies. The effects of oleamide (OEA), a fatty acid primary amide with activity on cannabinoid receptors, was tested against mitochondrial toxicity induced by the electron transport chain complex II inhibitor, 3-nitropropionic acid (3-NP), in rat cortical slices. OEA prevented the 3-NP-induced loss of mitochondrial function/cell viability at a concentration range of 5 nM-25 µM, and this protective effect was observed only when the amide was administered as pretreatment, but not as post-treatment. The preservation of mitochondrial function/cell viability induced by OEA in the toxic model induced by 3-NP was lost when the slices were pre-incubated with the cannabinoid receptor 1 (CB1R) selective inhibitor, AM281, or the cannabinoid receptor 2 (CB2R) selective inhibitor, JTE-907. The 3-NP-induced inhibition of succinate dehydrogenase (mitochondrial Complex II) activity was recovered by 25 nM OEA. The amide also prevented the increased lipid peroxidation and the changes in reduced/oxidized glutathione (GSH/GSSG) ratio induced by 3-NP. The cell damage induced by 3-NP, assessed as incorporation of cellular propidium iodide, was mitigated by OEA. Our novel findings suggest that the neuroprotective properties displayed by OEA during the early stages of damage to cortical cells involve the converging activation of CB1R and CB2R and the increase in antioxidant activity, which combined may emerge from the preservation of the functional integrity of mitochondria.
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Yan X, Yang K, Xiao Q, Hou R, Pan X, Zhu X. Central role of microglia in sepsis-associated encephalopathy: From mechanism to therapy. Front Immunol 2022; 13:929316. [PMID: 35958583 PMCID: PMC9361477 DOI: 10.3389/fimmu.2022.929316] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 06/22/2022] [Indexed: 11/20/2022] Open
Abstract
Sepsis-associated encephalopathy (SAE) is a cognitive impairment associated with sepsis that occurs in the absence of direct infection in the central nervous system or structural brain damage. Microglia are thought to be macrophages of the central nervous system, devouring bits of neuronal cells and dead cells in the brain. They are activated in various ways, and microglia-mediated neuroinflammation is characteristic of central nervous system diseases, including SAE. Here, we systematically described the pathogenesis of SAE and demonstrated that microglia are closely related to the occurrence and development of SAE. Furthermore, we comprehensively discussed the function and phenotype of microglia and summarized their activation mechanism and role in SAE pathogenesis. Finally, this review summarizes recent studies on treating cognitive impairment in SAE by blocking microglial activation and toxic factors produced after activation. We suggest that targeting microglial activation may be a putative treatment for SAE.
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Affiliation(s)
- Xiaoqian Yan
- Department of Critical Care Medicine, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Kaiying Yang
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Qi Xiao
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Rongyao Hou
- Department of Neurology, The Affiliated Hiser Hospital of Qingdao University, Qingdao, China
- *Correspondence: Rongyao Hou, ; Xudong Pan, ; Xiaoyan Zhu,
| | - Xudong Pan
- Department of Neurology, The Affiliated Hospital of Qingdao University, Qingdao, China
- *Correspondence: Rongyao Hou, ; Xudong Pan, ; Xiaoyan Zhu,
| | - Xiaoyan Zhu
- Department of Critical Care Medicine, The Affiliated Hospital of Qingdao University, Qingdao, China
- *Correspondence: Rongyao Hou, ; Xudong Pan, ; Xiaoyan Zhu,
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