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Yao XQ, Chen JY, Garcia-Segura ME, Wen ZH, Yu ZH, Huang ZC, Hamel R, Liu JH, Shen X, Huang ZP, Lu YM, Zhou ZT, Liu CT, Shi JM, Zhu QA, Peruzzotti-Jametti L, Chen JT. Integrated multi-omics analysis reveals molecular changes associated with chronic lipid accumulation following contusive spinal cord injury. Exp Neurol 2024; 380:114909. [PMID: 39097074 DOI: 10.1016/j.expneurol.2024.114909] [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: 05/09/2024] [Revised: 06/23/2024] [Accepted: 07/29/2024] [Indexed: 08/05/2024]
Abstract
Functional and pathological recovery after spinal cord injury (SCI) is often incomplete due to the limited regenerative capacity of the central nervous system (CNS), which is further impaired by several mechanisms that sustain tissue damage. Among these, the chronic activation of immune cells can cause a persistent state of local CNS inflammation and damage. However, the mechanisms that sustain this persistent maladaptive immune response in SCI have not been fully clarified yet. In this study, we integrated histological analyses with proteomic, lipidomic, transcriptomic, and epitranscriptomic approaches to study the pathological and molecular alterations that develop in a mouse model of cervical spinal cord hemicontusion. We found significant pathological alterations of the lesion rim with myelin damage and axonal loss that persisted throughout the late chronic phase of SCI. This was coupled by a progressive lipid accumulation in myeloid cells, including resident microglia and infiltrating monocyte-derived macrophages. At tissue level, we found significant changes of proteins indicative of glycolytic, tricarboxylic acid cycle (TCA), and fatty acid metabolic pathways with an accumulation of triacylglycerides with C16:0 fatty acyl chains in chronic SCI. Following transcriptomic, proteomic, and epitranscriptomic studies identified an increase of cholesterol and m6A methylation in lipid-droplet-accumulating myeloid cells as a core feature of chronic SCI. By characterizing the multiple metabolic pathways altered in SCI, our work highlights a key role of lipid metabolism in the chronic response of the immune and central nervous system to damage.
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Affiliation(s)
- Xin-Qiang Yao
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Jia-Ying Chen
- Comprehensive Medical Treatment Ward, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Monica Emili Garcia-Segura
- Department of Metabolism, Digestion and Reproduction, Imperial College London, United Kingdom; Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Zi-Han Wen
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zi-Han Yu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zu-Cheng Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Regan Hamel
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Jun-Hao Liu
- Division of Spine Surgery, Department of Orthopaedics, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong, China
| | - Xing Shen
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhi-Ping Huang
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Yan-Meng Lu
- Central Laboratory, Southern Medical University, Guangzhou, Guangdong, China
| | - Zhi-Tao Zhou
- Central Laboratory, Southern Medical University, Guangzhou, Guangdong, China
| | - Cui-Ting Liu
- Central Laboratory, Southern Medical University, Guangzhou, Guangdong, China
| | - Jun-Min Shi
- Central Laboratory, Southern Medical University, Guangzhou, Guangdong, China
| | - Qing-An Zhu
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Luca Peruzzotti-Jametti
- Department of Metabolism, Digestion and Reproduction, Imperial College London, United Kingdom; Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Jian-Ting Chen
- Division of Spine Surgery, Department of Orthopaedics, Nanfang hospital, Southern Medical University, Guangzhou, Guangdong, China.
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Wang XX, Li ZH, Du HY, Liu WB, Zhang CJ, Xu X, Ke H, Peng R, Yang DG, Li JJ, Gao F. The role of foam cells in spinal cord injury: challenges and opportunities for intervention. Front Immunol 2024; 15:1368203. [PMID: 38545108 PMCID: PMC10965697 DOI: 10.3389/fimmu.2024.1368203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 02/22/2024] [Indexed: 04/17/2024] Open
Abstract
Spinal cord injury (SCI) results in a large amount of tissue cell debris in the lesion site, which interacts with various cytokines, including inflammatory factors, and the intrinsic glial environment of the central nervous system (CNS) to form an inhibitory microenvironment that impedes nerve regeneration. The efficient clearance of tissue debris is crucial for the resolution of the inhibitory microenvironment after SCI. Macrophages are the main cells responsible for tissue debris removal after SCI. However, the high lipid content in tissue debris and the dysregulation of lipid metabolism within macrophages lead to their transformation into foamy macrophages during the phagocytic process. This phenotypic shift is associated with a further pro-inflammatory polarization that may aggravate neurological deterioration and hamper nerve repair. In this review, we summarize the phenotype and metabolism of macrophages under inflammatory conditions, as well as the mechanisms and consequences of foam cell formation after SCI. Moreover, we discuss two strategies for foam cell modulation and several potential therapeutic targets that may enhance the treatment of SCI.
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Affiliation(s)
- Xiao-Xin Wang
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Ze-Hui Li
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Hua-Yong Du
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Wu-Bo Liu
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
- Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Chun-Jia Zhang
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Xin Xu
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Han Ke
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
- Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Run Peng
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - De-Gang Yang
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
| | - Jian-Jun Li
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
- Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
- Institute of Rehabilitation Medicine, China Rehabilitation Research Center, Beijing, China
| | - Feng Gao
- School of Rehabilitation, Capital Medical University, Beijing, China
- Department of Spinal and Neural Functional Reconstruction, China Rehabilitation Research Center, Beijing, China
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Liu S, Yang S, Zhu X, Li X, Zhang X, Zhou X, Cheng H, Huo FQ, Mao Q, Liang L. Spinal apolipoprotein E is involved in inflammatory pain via regulating lipid metabolism and glial activation in the spinal dorsal horn. Biol Direct 2023; 18:85. [PMID: 38071369 PMCID: PMC10710718 DOI: 10.1186/s13062-023-00444-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 12/06/2023] [Indexed: 12/18/2023] Open
Abstract
INTRODUCTION Inflammation and nerve injury promote astrocyte activation, which regulates the development and resolution of pain, in the spinal dorsal horn. APOE regulates lipid metabolism and is predominantly expressed in the astrocytes. However, the effect of astrocytic APOE and lipid metabolism on spinal cellular function is unclear. This study aimed to investigate the effect of spinal Apoe on spinal cellular functions using the complete Freund's adjuvant (CFA)-induced inflammatory pain mouse model. METHODS After intraplantar injection of CFA, we assessed pain behaviors in C57BL6 and Apoe knockout (Apoe-/-) mice using von Frey and Hargreaves' tests and analyzed dorsal horn samples (L4-5) using western blotting, immunofluorescence, quantitative real-time polymerase chain reaction, and RNA sequencing. RESULTS The Apoe levels were markedly upregulated at 2 h and on days 1 and 3 post-CFA treatment. Apoe was exclusively expressed in the astrocytes. Apoe-/- mice exhibited decreased pain on day 1, but not at 2 h, post-CFA treatment. Apoe-/- mice also showed decreased spinal neuron excitability and paw edema on day 1 post-CFA treatment. Global transcriptomic analysis of the dorsal horn on day 1 post-CFA treatment revealed that the differentially expressed mRNAs in Apoe-/- mice were associated with lipid metabolism and the immune system. Astrocyte activation was impaired in Apoe-/- mice on day 1 post-CFA treatment. The intrathecal injection of Apoe antisense oligonucleotide mitigated CFA-induced pain hypersensitivity. CONCLUSIONS Apoe deficiency altered lipid metabolism in astrocytes, exerting regulatory effects on immune response, astrocyte activation, and neuronal activity and consequently disrupting the maintenance of inflammatory pain after peripheral inflammation. Targeting APOE is a potential anti-nociception and anti-inflammatory strategy.
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Affiliation(s)
- Siyi Liu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
| | - Shuting Yang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
| | - Xuan Zhu
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Department of Anesthesiology, Central Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, People's Republic of China
| | - Xiang Li
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
| | - Xi Zhang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
| | - Xiaoqiong Zhou
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
| | - Hong Cheng
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
| | - Fu-Quan Huo
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education, Xi'an, Shaanxi, People's Republic of China
| | - Qingxiang Mao
- Department of Anesthesiology, Daping Hospital, Army Medical University, Chongqing, People's Republic of China.
| | - Lingli Liang
- Department of Physiology and Pathophysiology, School of Basic Medical Sciences, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China.
- Institute of Neuroscience, Translational Medicine Institute, Xi'an Jiaotong University Health Science Center, Xi'an, Shaanxi, People's Republic of China.
- Key Laboratory of Environment and Genes Related to Diseases, Xi'an Jiaotong University, Ministry of Education, Xi'an, Shaanxi, People's Republic of China.
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Li H, Liu P, Deng S, Zhu L, Cao X, Bao X, Xia S, Xu Y, Zhang B. Pharmacological Upregulation of Microglial Lipid Droplet Alleviates Neuroinflammation and Acute Ischemic Brain Injury. Inflammation 2023; 46:1832-1848. [PMID: 37450211 PMCID: PMC10567859 DOI: 10.1007/s10753-023-01844-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/09/2023] [Accepted: 05/16/2023] [Indexed: 07/18/2023]
Abstract
Lipid droplets (LDs) were reported to play an important role in the modulation of inflammation and various cellular processes among multiple cell types. However, LDs accumulation, its function and mechanisms of its formation during ischemic stroke remained poorly-identified. In this study, we observed increased LDs accumulation in microglia at the acute stage of ischemic stroke by immunofluorescence and flow cytometry. Transcriptomic analysis indicated that microglia accumulated with LDs were associated with inflammation and phagocytosis. Both inflammatory activation and phagocytosis of tissue debris in microglia could contribute to LDs formation. Moreover, through specific LDs depletion and overload experiments by pharmacological approaches, we proposed that LDs was critical for the maintenance of anti-inflammatory properties of microglia. Furthermore, Atglistatin, a specific adipose triglyceride lipase (ATGL) inhibitor, was shown to prevent proinflammatory cytokines production in primary microglia through decreased LDs lipolysis. After Atglistatin treatment, middle cerebral artery occlusion (MCAO) mice showed decreased infarct volume and improved neurobehavioral performance at the acute stage of stroke. Our findings provided a biological basis for microglial LDs regulation as a potential therapeutic strategy for acute ischemic stroke and uncovered the neuroprotective role of Atglistatin in the treatment of MCAO mice.
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Affiliation(s)
- Huiya Li
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Pinyi Liu
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Shiji Deng
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Liwen Zhu
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Xiang Cao
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Xinyu Bao
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Shengnan Xia
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Yun Xu
- Department of Neurology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China
| | - Bing Zhang
- Department of Radiology, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China.
- Institute of Medical Imaging and Artificial Intelligence, Nanjing University, Nanjing, 210008, China.
- Medical Imaging Center, Nanjing Drum Tower Hospital, Affiliated Hospital of Medical School, Nanjing University, Nanjing, 210008, China.
- Jiangsu Key Laboratory of Molecular Medicine, Nanjing, 210008, China.
- Institute of Brain Science, Nanjing University, Nanjing, 210008, China.
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Zhang S, Ma Y, Luo X, Xiao H, Cheng R, Jiang A, Qin X. Integrated Analysis of Immune Infiltration and Hub Pyroptosis-Related Genes for Multiple Sclerosis. J Inflamm Res 2023; 16:4043-4059. [PMID: 37727371 PMCID: PMC10505586 DOI: 10.2147/jir.s422189] [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: 06/08/2023] [Accepted: 09/02/2023] [Indexed: 09/21/2023] Open
Abstract
Purpose Studies on overall immune infiltration and pyroptosis in patients with multiple sclerosis (MS) are limited. This study explored immune cell infiltration and pyroptosis in MS using bioinformatics and experimental validation. Methods The GSE131282 and GSE135511 microarray datasets including brain autopsy tissues from controls and MS patients were downloaded for bioinformatic analysis. The gene expression-based deconvolution method, CIBERSORT, was used to determine immune infiltration. Differentially expressed genes (DEGs) and functional enrichments were analyzed. We then extracted pyroptosis-related genes (PRGs) from the DEGs by using machine learning strategies. Their diagnostic ability for MS was evaluated in both the training set (GSE131282 dataset) and validation set (GSE135511 dataset). In addition, messenger RNA (mRNA) expression of PRGs was validated using quantitative real-time polymerase chain reaction (qRT-PCR) in cortical tissue from an experimental autoimmune encephalomyelitis (EAE) model of MS. Moreover, the functional enrichment pathways of each hub PRG were estimated. Finally, co-expressed competitive endogenous RNA (ceRNA) networks of PRGs in MS were constructed. Results Among the infiltrating cells, naive CD4+ T cells (P=0.006), resting NK cells (P=0.002), activated mast cells (P=0.022), and neutrophils (P=0.002) were significantly higher in patients with MS than in controls. The DEGs of MS were screened. Analysis of enrichment pathways showed that the pathways of transcriptional regulatory mechanisms and ion channels associating with pyroptosis. Four PRGs genes CASP4, PLCG1, CASP9 and NLRC4 were identified. They were validated in both the GSE135511 dataset and the EAE model by using qRT-PCR. CASP4 and NLRC4 were ultimately identified as stable hub PRGs for MS. Single-gene Gene Set Enrichment Analysis showed that they mainly participated in biosynthesis, metabolism, and organism resistance. ceRNA networks containing CASP4 and NLRC4 were constructed. Conclusion MS was associated with immune infiltration. CASP4 and NLRC4 were key biomarkers of pyroptosis in MS.
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Affiliation(s)
- Shaoru Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Yue Ma
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Xiaoqin Luo
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Hongmei Xiao
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Ruiqi Cheng
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Anan Jiang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
| | - Xinyue Qin
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, People’s Republic of China
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Jiang C, Chen Z, Wang X, Zhang Y, Guo X, Fan H, Huang D, He Y, Tang X, Ai Y, Liu Y, Yang H, Hao D. Curcumin-activated Olfactory Ensheathing Cells Improve Functional Recovery After Spinal Cord Injury by Modulating Microglia Polarization Through APOE/TREM2/NF-κB Signaling Pathway. J Neuroimmune Pharmacol 2023; 18:476-494. [PMID: 37658943 PMCID: PMC10577109 DOI: 10.1007/s11481-023-10081-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 08/02/2023] [Indexed: 09/05/2023]
Abstract
Transplantation of curcumin-activated olfactory ensheathing cells (aOECs) improved functional recovery in spinal cord injury (SCI) rats. Nevertheless, little is known considering the underlying mechanisms. At the present study, we investigated the promotion of regeneration and functional recovery after transplantation of aOECs into rats with SCI and the possible underlying molecular mechanisms. Primary OECs were prepared from the olfactory bulb of rats, followed by treatment with 1µM CCM at 7-10 days of culture, resulting in cell activation. Concomitantly, rat SCI model was developed to evaluate the effects of transplantation of aOECs in vivo. Subsequently, microglia were isolated, stimulated with 100 ng/mL lipopolysaccharide (LPS) for 24 h to polarize to M1 phenotype and treated by aOECs conditional medium (aOECs-CM) and OECs conditional medium (OECs-CM), respectively. Changes in the expression of pro-inflammatory and anti-inflammatory phenotypic markers expression were detected using western blotting and immunofluorescence staining, respectively. Finally, a series of molecular biological experiments including knock-down of triggering receptor expressed on myeloid cells 2 (TREM2) and analysis of the level of apolipoprotein E (APOE) expression were performed to investigate the underlying mechanism of involvement of CCM-activated OECs in modulating microglia polarization, leading to neural regeneration and function recovery. CCM-activated OECs effectively attenuated deleterious inflammation by regulating microglia polarization from the pro-inflammatory (M1) to anti-inflammatory (M2) phenotype in SCI rats and facilitated functional recovery after SCI. In addition, microglial polarization to M2 elicited by aOECs-CM in LPS-induced microglia was effectively reversed when TREM2 expression was downregulated. More importantly, the in vitro findings indicated that aOECs-CM potentiating LPS-induced microglial polarization to M2 was partially mediated by the TREM2/nuclear factor kappa beta (NF-κB) signaling pathway. Besides, the expression of APOE significantly increased in CCM-treated OECs. CCM-activated OECs could alleviate inflammation after SCI by switching microglial polarization from M1 to M2, which was likely mediated by the APOE/TREM2/NF-κB pathway, and thus ameliorated neurological function. Therefore, the present finding is of paramount significance to enrich the understanding of underlying molecular mechanism of aOECs-based therapy and provide a novel therapeutic approach for treatment of SCI.
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Affiliation(s)
- Chao Jiang
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
| | - Zhe Chen
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
| | - Xiaohui Wang
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
| | - Yongyuan Zhang
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
| | - Xinyu Guo
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
- Translational Medicine Center, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
| | - Hong Fan
- Translational Medicine Center, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Department of Neurology, The Second Affiliated Hospital of Xi’an Jiaotong University, Xi’an, 710004 China
| | - Dageng Huang
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
| | - Yuqing He
- Translational Medicine Center, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
| | - Xiangwen Tang
- Translational Medicine Center, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Basic Medical School Academy, Shaanxi University of Traditional Chinese Medicine, Xianyang, 712046 China
| | - Yixiang Ai
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
| | - Youjun Liu
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
| | - Hao Yang
- Translational Medicine Center, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
| | - Dingjun Hao
- Department of Spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Xi’an, 710054 China
- Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
- Department of spine Surgery, Hong Hui Hospital, Xi’an Jiaotong University, Shaanxi Key Laboratory of Spine Bionic Treatment, Xi’an, 710054 China
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7
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Li Q, Kang X, Liu L, Xiao Y, Xu D, Zhuang H, Liu H, Zhao J, Zou H, Yang J, Zhan X, Li T, Wang X, Liu L. Adult mice with noise-induced hearing loss exhibited temporal ordering memory deficits accompanied by microglia-associated neuroplastic changes in the medial prefrontal cortex. Neurobiol Dis 2023:106181. [PMID: 37271287 DOI: 10.1016/j.nbd.2023.106181] [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: 12/17/2022] [Revised: 05/17/2023] [Accepted: 05/30/2023] [Indexed: 06/06/2023] Open
Abstract
Acquired peripheral hearing loss in midlife is considered the primary modifiable risk factor for dementia, while the underlying pathological mechanism remains poorly understood. Excessive noise exposure is the most common cause of acquired peripheral hearing loss in modern society. This study was designed to investigate the impact of noise-induced hearing loss (NIHL) on cognition, with a focus on the medial prefrontal cortex (mPFC), a brain region that is involved in both auditory and cognitive processes and is highly affected in patients with cognitive impairment. Adult C57BL/6 J mice were randomly assigned to a control group and seven noise groups: 0HPN, 12HPN, 1DPN, 3DPN, 7DPN, 14DPN, and 28DPN, which were exposed to broadband noise at a 123 dB sound pressure level (SPL) for 2 h and sacrificed immediately (0 h), 12 h, or 1, 3, 7, 14, or 28 days post-noise exposure (HPN, DPN), respectively. Hearing assessment, behavioral tests, and neuromorphological studies in the mPFC were performed in control and 28DPN mice. All experimental animals were included in the time-course analysis of serum corticosterone (CORT) levels and mPFC microglial morphology. The results illustrated that noise exposure induced early-onset transient serum CORT elevation and permanent moderate-to-severe hearing loss in mice. 28DPN mice, in which permanent NIHL has been verified, exhibited impaired performance in temporal order object recognition tasks concomitant with reduced structural complexity of mPFC pyramidal neurons. The time-course immunohistochemical analysis in the mPFC revealed significantly higher morphological microglial activation at 14 and 28 DPN, preceded by a remarkably higher amount of microglial engulfed postsynaptic marker PSD95 at 7 DPN. Additionally, lipid accumulation in microglia was observed in 7DPN, 14DPN and 28DPN mice, suggesting a driving role of lipid handling deficits following excessive phagocytosis of synaptic elements in delayed and sustained microglial abnormalities. These findings provide fundamentally novel information concerning mPFC-related cognitive impairment in mice with NIHL and empirical evidence suggesting the involvement of microglial malfunction in the mPFC neurodegenerative consequences of NIHL.
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Affiliation(s)
- Qian Li
- Medical College, Southeast University, Nanjing 210009, China
| | - Xiaomin Kang
- School of Life Science and Technology, Southeast University, Nanjing 210096, China
| | - Linchen Liu
- Department of Rheumatology, Zhongda Hospital, Medical School of Southeast University, Nanjing 210009, China
| | - Yu Xiao
- Medical College, Southeast University, Nanjing 210009, China
| | - Dan Xu
- School of Public Health, Southeast University, Nanjing 210009, China
| | - Hong Zhuang
- Medical College, Southeast University, Nanjing 210009, China
| | - Haiqing Liu
- School of Life Science and Technology, Southeast University, Nanjing 210096, China
| | - Jingyi Zhao
- School of Life Science and Technology, Southeast University, Nanjing 210096, China
| | - Han Zou
- Medical College, Southeast University, Nanjing 210009, China
| | - Jianing Yang
- Medical College, Southeast University, Nanjing 210009, China
| | - Xindi Zhan
- Medical College, Southeast University, Nanjing 210009, China
| | - Tianxiao Li
- Medical College, Southeast University, Nanjing 210009, China
| | - Xinchen Wang
- Medical College, Southeast University, Nanjing 210009, China
| | - Lijie Liu
- Jiangsu Provincial Key Laboratory of Critical Care Medicine, Department of Physiology, School of Medicine, Southeast University, Nanjing 210009, China.
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8
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Zheng B, He Y, Yin S, Zhu X, Zhao Q, Yang H, Wang Z, Zhu R, Cheng L. Unresolved Excess Accumulation of Myelin-Derived Cholesterol Contributes to Scar Formation after Spinal Cord Injury. RESEARCH (WASHINGTON, D.C.) 2023; 6:0135. [PMID: 37223476 PMCID: PMC10202378 DOI: 10.34133/research.0135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 04/13/2023] [Indexed: 05/25/2023]
Abstract
Spinal cord injury triggers complex pathological cascades, resulting in destructive tissue damage and incomplete tissue repair. Scar formation is generally considered a barrier for regeneration in the central nervous system. However, the intrinsic mechanism of scar formation after spinal cord injury has not been fully elucidated. Here, we report that excess cholesterol accumulates in phagocytes and is inefficiently removed from spinal cord lesions in young adult mice. Interestingly, we observed that excessive cholesterol also accumulates in injured peripheral nerves but is subsequently removed by reverse cholesterol transport. Meanwhile, preventing reverse cholesterol transport leads to macrophage accumulation and fibrosis in injured peripheral nerves. Furthermore, the neonatal mouse spinal cord lesions are devoid of myelin-derived lipids and can heal without excess cholesterol accumulation. We found that transplantation of myelin into neonatal lesions disrupts healing with excessive cholesterol accumulation, persistent macrophage activation, and fibrosis. Myelin internalization suppresses macrophage apoptosis mediated by CD5L expression, indicating that myelin-derived cholesterol plays a critical role in impaired wound healing. Taken together, our data suggest that the central nervous system lacks an efficient approach for cholesterol clearance, resulting in excessive accumulation of myelin-derived cholesterol, thereby inducing scar formation after injury.
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Affiliation(s)
- Bolin Zheng
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
| | - Yijing He
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
| | - Shuai Yin
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
| | - Xu Zhu
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
| | - Qing Zhao
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
| | - Huiyi Yang
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
| | - Zhaojie Wang
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
- Frontier Science Center for Stem Cell Research, School of Life Science and Technology,
Tongji University, Shanghai 200092, China
| | - Rongrong Zhu
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
- Frontier Science Center for Stem Cell Research, School of Life Science and Technology,
Tongji University, Shanghai 200092, China
| | - Liming Cheng
- Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration, Ministry of Education, Department of Orthopedics, Tongji Hospital, School of Medicine,
Tongji University, Shanghai 200092, China
- Clinical Center for Brain and Spinal Cord Research,
Tongji University, Shanghai 200092, China
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