1
|
Hasavci D, Blank T. A microglial compliment: controlling neuronal function from within. Signal Transduct Target Ther 2024; 9:267. [PMID: 39370427 PMCID: PMC11456583 DOI: 10.1038/s41392-024-01989-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2024] [Revised: 09/15/2024] [Accepted: 09/24/2024] [Indexed: 10/08/2024] Open
Affiliation(s)
- Dilara Hasavci
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Thomas Blank
- Institute of Neuropathology, Faculty of Medicine, University of Freiburg, Freiburg, Germany.
| |
Collapse
|
2
|
Chokr SM, Bui-Tran A, Cramer KS. Loss of C1q alters the auditory brainstem response. Front Cell Neurosci 2024; 18:1464670. [PMID: 39416682 PMCID: PMC11480778 DOI: 10.3389/fncel.2024.1464670] [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: 07/14/2024] [Accepted: 08/30/2024] [Indexed: 10/19/2024] Open
Abstract
Neural circuits in the auditory brainstem compute interaural time and intensity differences used to determine the locations of sound sources. These circuits display features that are specialized for these functions. The projection from the ventral cochlear nucleus (VCN) to the medial nucleus of the trapezoid (MNTB) body travels along highly myelinated fibers and terminates in the calyx of Held. This monoinnervating synapse emerges during development as multiple inputs are eliminated. We previously demonstrated that elimination of microglia with a colony stimulating factor-1 inhibitor results in impaired synaptic pruning so that multiple calyceal terminals reside on principal cells of MNTB. This inhibitor also resulted in impaired auditory brainstem responses (ABRs), with elevated thresholds and increased peak latencies. Loss of the microglial fractalkine receptor, CX3CR1, decreased peak latencies in the ABR. The mechanisms underlying these effects are not known. One prominent microglial signaling pathway involved in synaptic pruning and plasticity during development and aging is the C1q-initiated compliment cascade. Here we investigated the classical complement pathway initiator, C1q, in auditory brainstem maturation. We found that C1q expression is detected in the MNTB by the first postnatal week. C1q levels increased with age and were detected within microglia and surrounding the soma of MNTB principal neurons. Loss of C1q did not affect microglia-dependent calyceal pruning. Excitatory and inhibitory synaptic markers in the MNTB and LSO were not altered with C1q deletion. ABRs showed that C1q KO mice had normal hearing thresholds but shortened peak latencies. Altogether this study uncovers the developmental time frame of C1q expression in the sound localization pathway and shows a subtle functional consequence of C1q knockdown.
Collapse
Affiliation(s)
| | | | - Karina S. Cramer
- Department of Neurobiology and Behavior, University of California Irvine, Irvine, CA, United States
| |
Collapse
|
3
|
DeVries SA, Dimovasili C, Medalla M, Moore TL, Rosene DL. Dysregulated C1q and CD47 in the aging monkey brain: association with myelin damage, microglia reactivity, and cognitive decline. Front Immunol 2024; 15:1426975. [PMID: 39399501 PMCID: PMC11466761 DOI: 10.3389/fimmu.2024.1426975] [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: 05/02/2024] [Accepted: 08/28/2024] [Indexed: 10/15/2024] Open
Abstract
Normal aging, though lacking widespread neurodegeneration, is nevertheless characterized by cognitive impairment in learning, memory, and executive function. The aged brain is spared from neuron loss, but white matter is lost and damage to myelin sheaths accumulates. This myelin damage is strongly associated with cognitive impairment. Although the cause of the myelin damage is not known, microglia dysregulation is a likely contributor. Immunologic proteins interact with microglial receptors to modulate microglia-mediated phagocytosis, which mediates myelin damage clearance and turn-over. Two such proteins, "eat me" signal C1q and "don't eat me" signal CD47, act in opposition with microglia. Both C1q and CD47 have been implicated in Multiple Sclerosis, a demyelinating disease, but whether they play a role in age-related myelin pathology is currently unknown. The present study investigates C1q and CD47 in relation to age-related myelin degeneration using multilabel immunofluorescence, RNAscope, and confocal microscopy in the cingulum bundle of male and female rhesus monkeys across the lifespan. Our findings showed significant age-related elevation in C1q localized to myelin basic protein, and this increase is associated with more severe cognitive impairment. In contrast, CD47 localization to myelin decreased in middle age and oligodendrocyte expression of CD47 RNA decreased with age. Lastly, microglia reactivity increased with age in association with the changes in C1q and CD47. Together, these results suggest disruption in the balance of "eat me" and "don't eat me" signals during normal aging, biasing microglia toward increased reactivity and phagocytosis of myelin, resulting in cognitive deficits.
Collapse
Affiliation(s)
- Sarah A. DeVries
- Laboratory for Cognitive Neurobiology, Dept of Anatomy & Neurobiology, Chobanian and Avedisian School of Medicine, Boston University, Boston, MA, United States
| | - Christina Dimovasili
- Laboratory for Cognitive Neurobiology, Dept of Anatomy & Neurobiology, Chobanian and Avedisian School of Medicine, Boston University, Boston, MA, United States
| | - Maria Medalla
- Laboratory of Neural Circuits and Ultrastructure, Dept of Anatomy & Neurobiology, Chobanian and Avedisian School of Medicine, Boston University, Boston, MA, United States
- Center for Systems Neuroscience, Boston University, Boston, MA, United States
| | - Tara L. Moore
- Center for Systems Neuroscience, Boston University, Boston, MA, United States
- Laboratory of Interventions for Cortical Injury and Cognitive Decline, Dept of Anatomy & Neurobiology, Chobanian and Avedisian School of Medicine, Boston University, Boston, MA, United States
| | - Douglas L. Rosene
- Laboratory for Cognitive Neurobiology, Dept of Anatomy & Neurobiology, Chobanian and Avedisian School of Medicine, Boston University, Boston, MA, United States
- Center for Systems Neuroscience, Boston University, Boston, MA, United States
| |
Collapse
|
4
|
Pavlou A, Mulenge F, Gern OL, Busker LM, Greimel E, Waltl I, Kalinke U. Orchestration of antiviral responses within the infected central nervous system. Cell Mol Immunol 2024; 21:943-958. [PMID: 38997413 PMCID: PMC11364666 DOI: 10.1038/s41423-024-01181-7] [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: 03/29/2024] [Accepted: 05/05/2024] [Indexed: 07/14/2024] Open
Abstract
Many newly emerging and re-emerging viruses have neuroinvasive potential, underscoring viral encephalitis as a global research priority. Upon entry of the virus into the CNS, severe neurological life-threatening conditions may manifest that are associated with high morbidity and mortality. The currently available therapeutic arsenal against viral encephalitis is rather limited, emphasizing the need to better understand the conditions of local antiviral immunity within the infected CNS. In this review, we discuss new insights into the pathophysiology of viral encephalitis, with a focus on myeloid cells and CD8+ T cells, which critically contribute to protection against viral CNS infection. By illuminating the prerequisites of myeloid and T cell activation, discussing new discoveries regarding their transcriptional signatures, and dissecting the mechanisms of their recruitment to sites of viral replication within the CNS, we aim to further delineate the complexity of antiviral responses within the infected CNS. Moreover, we summarize the current knowledge in the field of virus infection and neurodegeneration and discuss the potential links of some neurotropic viruses with certain pathological hallmarks observed in neurodegeneration.
Collapse
Affiliation(s)
- Andreas Pavlou
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Felix Mulenge
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Olivia Luise Gern
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Lena Mareike Busker
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
- Department of Pathology, University of Veterinary Medicine Hannover, Foundation, 30559, Hannover, Germany
| | - Elisabeth Greimel
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Inken Waltl
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany
| | - Ulrich Kalinke
- Institute for Experimental Infection Research, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Helmholtz Centre for Infection Research and the Hannover Medical School, 30625, Hannover, Germany.
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, 30625, Hannover, Germany.
| |
Collapse
|
5
|
An W, Zhou J, Qiu Z, Wang P, Han X, Cheng Y, He Z, An Y, Li S. Identification of crosstalk genes and immune characteristics between Alzheimer's disease and atherosclerosis. Front Immunol 2024; 15:1443464. [PMID: 39188714 PMCID: PMC11345154 DOI: 10.3389/fimmu.2024.1443464] [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: 06/04/2024] [Accepted: 07/25/2024] [Indexed: 08/28/2024] Open
Abstract
Background Advancements in modern medicine have extended human lifespan, but they have also led to an increase in age-related diseases such as Alzheimer's disease (AD) and atherosclerosis (AS). Growing research evidence indicates a close connection between these two conditions. Methods We downloaded four gene expression datasets related to AD and AS from the Gene Expression Omnibus (GEO) database (GSE33000, GSE100927, GSE44770, and GSE43292) and performed differential gene expression (DEGs) analysis using the R package "limma". Through Weighted gene correlation network analysis (WGCNA), we selected the gene modules most relevant to the diseases and intersected them with the DEGs to identify crosstalk genes (CGs) between AD and AS. Subsequently, we conducted functional enrichment analysis of the CGs using DAVID. To screen for potential diagnostic genes, we applied the least absolute shrinkage and selection operator (LASSO) regression and constructed a logistic regression model for disease prediction. We established a protein-protein interaction (PPI) network using STRING (https://cn.string-db.org/) and Cytoscape and analyzed immune cell infiltration using the CIBERSORT algorithm. Additionally, NetworkAnalyst (http://www.networkanalyst.ca) was utilized for gene regulation and interaction analysis, and consensus clustering was employed to determine disease subtypes. All statistical analyses and visualizations were performed using various R packages, with a significance level set at p<0.05. Results Through intersection analysis of disease-associated gene modules identified by DEGs and WGCNA, we identified a total of 31 CGs co-existing between AD and AS, with their biological functions primarily associated with immune pathways. LASSO analysis helped us identify three genes (C1QA, MT1M, and RAMP1) as optimal diagnostic CGs for AD and AS. Based on this, we constructed predictive models for both diseases, whose accuracy was validated by external databases. By establishing a PPI network and employing four topological algorithms, we identified four hub genes (C1QB, CSF1R, TYROBP, and FCER1G) within the CGs, closely related to immune cell infiltration. NetworkAnalyst further revealed the regulatory networks of these hub genes. Finally, defining C1 and C2 subtypes for AD and AS respectively based on the expression profiles of CGs, we found the C2 subtype exhibited immune overactivation. Conclusion This study utilized gene expression matrices and various algorithms to explore the potential links between AD and AS. The identification of CGs revealed interactions between these two diseases, with immune and inflammatory imbalances playing crucial roles in their onset and progression. We hope these findings will provide valuable insights for future research on AD and AS.
Collapse
Affiliation(s)
- Wenhao An
- Department of Neurosurgery, Sanbo Brain Hospital, Capital Medical University, Beijing, China
| | - Jiajun Zhou
- Department of Neurosurgery, Sanbo Brain Hospital, Capital Medical University, Beijing, China
| | - Zhiqiang Qiu
- Department of Neurosurgery, Sanbo Brain Hospital, Capital Medical University, Beijing, China
| | - Peishen Wang
- Department of Research and Development, Beijing Yihua Biotechnology Co., Ltd, Beijing, China
| | - Xinye Han
- Department of Research and Development, Beijing Yihua Biotechnology Co., Ltd, Beijing, China
| | - Yanwen Cheng
- Department of Research and Development, Beijing Yihua Biotechnology Co., Ltd, Beijing, China
| | - Zi He
- Department of Research and Development, Beijing Yihua Biotechnology Co., Ltd, Beijing, China
| | - Yihua An
- Department of Neurosurgery, Sanbo Brain Hospital, Capital Medical University, Beijing, China
| | - Shouwei Li
- Department of Neurosurgery, Sanbo Brain Hospital, Capital Medical University, Beijing, China
| |
Collapse
|
6
|
Monselise EBI, Vyazmensky M, Scherf T, Batushansky A, Fishov I. D-Glutamate production by stressed Escherichia coli gives a clue for the hypothetical induction mechanism of the ALS disease. Sci Rep 2024; 14:18247. [PMID: 39107374 PMCID: PMC11303787 DOI: 10.1038/s41598-024-68645-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2024] [Accepted: 07/25/2024] [Indexed: 08/10/2024] Open
Abstract
In the search for the origin of Amyotrophic Lateral Sclerosis disease (ALS), we hypothesized earlier (Monselise, 2019) that D-amino acids produced by stressed microbiome may serve as inducers of the disease development. Many examples of D-amino acid accumulation under various stress conditions were demonstrated in prokaryotic and eukaryotic cells. In this work, wild-type Escherichia coli, members of the digestive system, were subjected to carbon and nitrogen starvation stress. Using NMR and LC-MS techniques, we found for the first time that D-glutamate accumulated in the stressed bacteria but not in control cells. These results together with the existing knowledge, allow us to suggest a new insight into the pathway of ALS development: D-glutamate, produced by the stressed microbiome, induces neurobiochemical miscommunication setting on C1q of the complement system. Proving this insight may have great importance in preventive medicine of such MND modern-age diseases as ALS, Alzheimer, and Parkinson.
Collapse
Affiliation(s)
- Edna Ben-Izhak Monselise
- Department of Life Science, Bergman Campus, Ben-Gurion University of the Negev, 8441901, Beer-Sheva, Israel.
| | - Maria Vyazmensky
- Department of Life Science, Bergman Campus, Ben-Gurion University of the Negev, 8441901, Beer-Sheva, Israel
| | - Tali Scherf
- Department of Chemical Research Support, The Weizmann Institute of Science, 7610001, Rehovot, Israel
| | - Albert Batushansky
- Ilse Katz Institute for Nanoscale Science & Technology, Marcus Campus, Ben-Gurion University of the Negev, 8410501, Beer-Sheva, Israel
| | - Itzhak Fishov
- Department of Life Science, Bergman Campus, Ben-Gurion University of the Negev, 8441901, Beer-Sheva, Israel.
| |
Collapse
|
7
|
Ge R, Luan Z, Guo T, Xia S, Ye J, Xu J. The expression and biological role of complement C1s in esophageal squamous cell carcinoma. Open Life Sci 2024; 19:20220915. [PMID: 39071493 PMCID: PMC11282917 DOI: 10.1515/biol-2022-0915] [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: 10/31/2023] [Revised: 05/23/2024] [Accepted: 06/06/2024] [Indexed: 07/30/2024] Open
Abstract
The present work focused on investigating the role of the altered expression of complement C1s in proliferation and apoptosis of esophageal squamous cell carcinoma (ESCC) cells and explore its biological functions in ESCC, so as to lay a theoretical foundation and provide certain clinical reference for diagnosing and treating ESCC. Complement C1s expression within ESCC was assessed, and its clinical pathological characteristics in ESCC patients were analyzed. Subsequently, in vitro experiments were performed to further explore the mechanisms by which complement C1s affected ESCC. According to the results, complement C1s expression within ESCC markedly increased relative to adjacent non-cancerous samples. High C1s expression showed positive relation to race, residual lesion, and tumor location of ESCC patients. Complement C1s affected ESCC cell proliferation and apoptosis. Notably, C1s knockdown significantly inhibited ESCC cell proliferation and enhanced their apoptosis. C1s suppressed ESCC cell proliferation via Wnt1/β-catenin pathway and promoted their apoptosis through modulating the expression of Bcl2, Bax, and cleaved-caspase3.
Collapse
Affiliation(s)
- Ruomu Ge
- Central Laboratory, The Affiliated Taizhou People’s Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Taizhou, Jiangsu, 225300, P.R. China
- Anhui Province Key Laboratory of Infectious Diseases, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhengyun Luan
- Department of Clinical Laboratory, The Affiliated Taizhou People’s Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Taizhou, Jiangsu, 225300, P.R. China
| | - Ting Guo
- Central Laboratory, The Affiliated Taizhou People’s Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Taizhou, Jiangsu, 225300, P.R. China
| | - Sheng Xia
- School of Medicine, Jiangsu University School, Zhenjiang, Jiangsu, 212000, P.R. China
| | - Jun Ye
- Central Laboratory, The Affiliated Taizhou People’s Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Taizhou, Jiangsu, 225300, P.R. China
| | - Jie Xu
- Central Laboratory, The Affiliated Taizhou People’s Hospital of Nanjing Medical University, Taizhou School of Clinical Medicine, Nanjing Medical University, Taizhou, Jiangsu, 225300, P.R. China
| |
Collapse
|
8
|
Zhang G, Wang L, Wang J, Zeng J, Yu C. RNA sequencing of the thalamus and rostral ventral medulla in rats with chronic orofacial pain. J Neural Transm (Vienna) 2024; 131:739-753. [PMID: 38630191 DOI: 10.1007/s00702-024-02780-4] [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: 01/24/2024] [Accepted: 04/11/2024] [Indexed: 06/27/2024]
Abstract
Diagnosing and treating chronic orofacial pain is challenging due to its complex structure and limited understanding of its causes and mechanisms. In this study, we used RNA sequencing to identify differentially expressed genes (DEGs) in the rostral ventral medulla (RVM) and thalamus of rats with persistent orofacial pain, aiming to explore its development. DEGs were functionally analyzed using gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. Results showed a significant association between immune response and pain in this model. Key DEG mRNA expression trends were further validated using real-time quantitative polymerase chain reaction (RT-PCR), confirming their crucial roles in chronic orofacial pain. After injecting complete Freund's adjuvant (CFA) into the bilateral temporomandibular joint cavity for 14 days, we observed 293 upregulated genes and 14 downregulated genes in the RVM, and 1086 upregulated genes and 37 downregulated genes in the thalamus. Furthermore, we identified 27 common DEGs with altered expression (upregulation) in both the thalamus and RVM, including Cd74, C3, Cxcl13, C1qb, Itgal, Fcgr2b, C5ar1, and Tlr2, which are pain-associated genes. Protein-protein interaction (PPI) analysis using Cytoscape revealed the involvement of Toll-like receptors, complement system, differentiation clusters, and antigen presentation-related proteins in the interaction between the thalamus and RVM. The results of this study show that the immune system seems to have a more significant influence on chronic orofacial pain. There may be direct or indirect influence between the thalamus and RVM, which may participate in the regulation of chronic orofacial pain.
Collapse
Affiliation(s)
- Guangyan Zhang
- Department of Anesthesiology, Stomatological Hospital of Chongqing Medical University, No. 426 Songshi North Road, Yubei District, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Lan Wang
- Department of Anesthesiology, Stomatological Hospital of Chongqing Medical University, No. 426 Songshi North Road, Yubei District, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Jing Wang
- Department of Anesthesiology, Stomatological Hospital of Chongqing Medical University, No. 426 Songshi North Road, Yubei District, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Jie Zeng
- Department of Anesthesiology, Stomatological Hospital of Chongqing Medical University, No. 426 Songshi North Road, Yubei District, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases, Chongqing, China
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China
| | - Cong Yu
- Department of Anesthesiology, Stomatological Hospital of Chongqing Medical University, No. 426 Songshi North Road, Yubei District, Chongqing, China.
- Chongqing Key Laboratory of Oral Diseases, Chongqing, China.
- Chongqing Municipal Key Laboratory of Oral Biomedical Engineering of Higher Education, Chongqing, China.
| |
Collapse
|
9
|
Beaver M, Bergdolt L, Dunaevsky A, Kielian T, Skar GL. C1q is elevated during chronic Staphylococcus epidermidis central nervous system catheter infection. Front Immunol 2024; 15:1342467. [PMID: 38881889 PMCID: PMC11176433 DOI: 10.3389/fimmu.2024.1342467] [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: 11/21/2023] [Accepted: 05/13/2024] [Indexed: 06/18/2024] Open
Abstract
Introduction Significant neurologic morbidity is caused by pediatric cerebrospinal fluid (CSF) shunt infections. The underlying mechanisms leading to impaired school performance and increased risk of seizures are unknown, however, a better understanding of these mechanisms may allow us to temper their consequences. Recent evidence has demonstrated important roles for complement proteins in neurodevelopment and neuroinflammation. Methods We examined complement activation throughout Staphylococcus epidermidis (S. epidermidis) central nervous system (CNS) catheter infection. In addition, based on accumulating evidence that C3 plays a role in synaptic pruning in other neuroinflammatory states we determined if C3 and downstream C5 led to alterations in synaptic protein levels. Using our murine model of S. epidermidis catheter infection we quantified levels of the complement components C1q, Factor B, MASP2, C3, and C5 over the course of infection along with bacterial burdens. Results We found that MASP2 predominated early in catheter infection, but that Factor B was elevated at intermediate time points. Unexpectedly C1q was elevated at late timepoints when bacterial burdens were low or undetectable. Based on these findings and the wealth of information regarding the emerging roles of C1q in the CNS, this suggests functions beyond pathogen elimination during S. epidermidis CNS catheter infection. To identify if C3 impacted synaptic protein levels we performed synaptosome isolation and quantified levels of VGLUT1 and PSD95 as well as pre-, post- and total synaptic puncta in cortical layer V of C3 knockout (KO) and wild type mice. We also used C5 KO and wild type mice to determine if there was any difference in pre-, post- and total synaptic puncta. Discussion Neither C3 nor C5 impacted synaptic protein abundance. These findings suggest that chronic elevations in C1q in the brain that persist once CNS catheter infection has resolved may be modulating disease sequalae.
Collapse
Affiliation(s)
- Matthew Beaver
- Department of Pediatrics, University of Nebraska Medical Center, Omaha, NE, United States
| | - Lara Bergdolt
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, United States
| | - Anna Dunaevsky
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha, NE, United States
| | - Tammy Kielian
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, United States
| | - Gwenn L. Skar
- Department of Pediatrics, University of Nebraska Medical Center, Omaha, NE, United States
| |
Collapse
|
10
|
Field SE, Curle AJ, Barker RA. Inflammation and Huntington's disease - a neglected therapeutic target? Expert Opin Investig Drugs 2024; 33:451-467. [PMID: 38758356 DOI: 10.1080/13543784.2024.2348738] [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: 12/19/2023] [Accepted: 04/24/2024] [Indexed: 05/18/2024]
Abstract
INTRODUCTION Huntington's Disease (HD) is a genetic neurodegenerative disease for which there is currently no disease-modifying treatment. One of several underlying mechanisms proposed to be involved in HD pathogenesis is inflammation; there is now accumulating evidence that the immune system may play an integral role in disease pathology and progression. As such, modulation of the immune system could be a potential therapeutic target for HD. AREAS COVERED To date, the number of trials targeting immune aspects of HD has been limited. However, targeting it, may have great advantages over other therapeutic areas, given that many drugs already exist that have actions in this system coupled to the fact that inflammation can be measured both peripherally and, to some extent, centrally using CSF and PET imaging. In this review, we look at evidence that the immune system and the newly emerging area of the microbiome are altered in HD patients, and then present and discuss clinical trials that have targeted different parts of the immune system. EXPERT OPINION We then conclude by discussing how this field might develop going forward, focusing on the role of imaging and other biomarkers to monitor central immune activation and response to novel treatments in HD.
Collapse
Affiliation(s)
- Sophie E Field
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, and MRC-WT Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Annabel J Curle
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, and MRC-WT Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| | - Roger A Barker
- Department of Clinical Neurosciences, John van Geest Centre for Brain Repair, and MRC-WT Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK
| |
Collapse
|
11
|
Tang S, Hu W, Zou H, Luo Q, Deng W, Cao S. The complement system: a potential target for the comorbidity of chronic pain and depression. Korean J Pain 2024; 37:91-106. [PMID: 38433474 PMCID: PMC10985490 DOI: 10.3344/kjp.23284] [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: 10/10/2023] [Revised: 11/28/2023] [Accepted: 12/16/2023] [Indexed: 03/05/2024] Open
Abstract
The mechanisms of the chronic pain and depression comorbidity have gained significant attention in recent years. The complement system, widely involved in central nervous system diseases and mediating non-specific immune mechanisms in the body, remains incompletely understood in its involvement in the comorbidity mechanisms of chronic pain and depression. This review aims to consolidate the findings from recent studies on the complement system in chronic pain and depression, proposing that it may serve as a promising shared therapeutic target for both conditions. Complement proteins C1q, C3, C5, as well as their cleavage products C3a and C5a, along with the associated receptors C3aR, CR3, and C5aR, are believed to have significant implications in the comorbid mechanism. The primary potential mechanisms encompass the involvement of the complement cascade C1q/C3-CR3 in the activation of microglia and synaptic pruning in the amygdala and hippocampus, the role of complement cascade C3/C3a-C3aR in the interaction between astrocytes and microglia, leading to synaptic pruning, and the C3a-C3aR axis and C5a-C5aR axis to trigger inflammation within the central nervous system. We focus on studies on the role of the complement system in the comorbid mechanisms of chronic pain and depression.
Collapse
Affiliation(s)
- Shanshan Tang
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Wen Hu
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Helin Zou
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Qingyang Luo
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Wenwen Deng
- Department of Cardiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
| | - Song Cao
- Department of Anesthesiology, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- Department of Pain Medicine, Affiliated Hospital of Zunyi Medical University, Zunyi, China
- Guizhou Key Laboratory of Anesthesia and Organ Protection, Zunyi Medical University, Zunyi, China
| |
Collapse
|
12
|
Nimmo J, Byrne R, Daskoulidou N, Watkins L, Carpanini S, Zelek W, Morgan B. The complement system in neurodegenerative diseases. Clin Sci (Lond) 2024; 138:387-412. [PMID: 38505993 PMCID: PMC10958133 DOI: 10.1042/cs20230513] [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: 10/31/2023] [Revised: 02/15/2024] [Accepted: 03/01/2024] [Indexed: 03/21/2024]
Abstract
Complement is an important component of innate immune defence against pathogens and crucial for efficient immune complex disposal. These core protective activities are dependent in large part on properly regulated complement-mediated inflammation. Dysregulated complement activation, often driven by persistence of activating triggers, is a cause of pathological inflammation in numerous diseases, including neurological diseases. Increasingly, this has become apparent not only in well-recognized neuroinflammatory diseases like multiple sclerosis but also in neurodegenerative and neuropsychiatric diseases where inflammation was previously either ignored or dismissed as a secondary event. There is now a large and rapidly growing body of evidence implicating complement in neurological diseases that cannot be comprehensively addressed in a brief review. Here, we will focus on neurodegenerative diseases, including not only the 'classical' neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease, but also two other neurological diseases where neurodegeneration is a neglected feature and complement is implicated, namely, schizophrenia, a neurodevelopmental disorder with many mechanistic features of neurodegeneration, and multiple sclerosis, a demyelinating disorder where neurodegeneration is a major cause of progressive decline. We will discuss the evidence implicating complement as a driver of pathology in these diverse diseases and address briefly the potential and pitfalls of anti-complement drug therapy for neurodegenerative diseases.
Collapse
Affiliation(s)
- Jacqui Nimmo
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Robert A.J. Byrne
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Nikoleta Daskoulidou
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Lewis M. Watkins
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Sarah M. Carpanini
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - Wioleta M. Zelek
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| | - B. Paul Morgan
- UK Dementia Research Institute Cardiff, Cardiff University, Cardiff CF24 4HQ, U.K
| |
Collapse
|
13
|
Rodriguez D, Church KA, Pietramale AN, Cardona SM, Vanegas D, Rorex C, Leary MC, Muzzio IA, Nash KR, Cardona AE. Fractalkine isoforms differentially regulate microglia-mediated inflammation and enhance visual function in the diabetic retina. J Neuroinflammation 2024; 21:42. [PMID: 38311721 PMCID: PMC10840196 DOI: 10.1186/s12974-023-02983-8] [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: 10/24/2023] [Accepted: 12/01/2023] [Indexed: 02/06/2024] Open
Abstract
Diabetic retinopathy (DR) affects about 200 million people worldwide, causing leakage of blood components into retinal tissues, leading to activation of microglia, the resident phagocytes of the retina, promoting neuronal and vascular damage. The microglial receptor, CX3CR1, binds to fractalkine (FKN), an anti-inflammatory chemokine that is expressed on neuronal membranes (mFKN), and undergoes constitutive cleavage to release a soluble domain (sFKN). Deficiencies in CX3CR1 or FKN showed increased microglial activation, inflammation, vascular damage, and neuronal loss in experimental mouse models. To understand the mechanism that regulates microglia function, recombinant adeno-associated viral vectors (rAAV) expressing mFKN or sFKN were delivered to intact retinas prior to diabetes. High-resolution confocal imaging and mRNA-seq were used to analyze microglia morphology and markers of expression, neuronal and vascular health, and inflammatory mediators. We confirmed that prophylactic intra-vitreal administration of rAAV expressing sFKN (rAAV-sFKN), but not mFKN (rAAV-mFKN), in FKNKO retinas provided vasculo- and neuro-protection, reduced microgliosis, mitigated inflammation, improved overall optic nerve health by regulating microglia-mediated inflammation, and prevented fibrin(ogen) leakage at 4 weeks and 10 weeks of diabetes induction. Moreover, administration of sFKN improved visual acuity. Our results elucidated a novel intervention via sFKN gene therapy that provides an alternative pathway to implement translational and therapeutic approaches, preventing diabetes-associated blindness.
Collapse
Affiliation(s)
- Derek Rodriguez
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Kaira A Church
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Alicia N Pietramale
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Sandra M Cardona
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Difernando Vanegas
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Colin Rorex
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Micah C Leary
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
| | - Isabel A Muzzio
- Department of Psychological and Brain Sciences, University of Iowa, Iowa City, IA, 52242, USA
| | - Kevin R Nash
- Department of Molecular Pharmacology and Physiology, University of South Florida, Tampa, FL, 33620, USA
| | - Astrid E Cardona
- Department of Molecular Microbiology and Immunology, UTSA Circle, The University of Texas at San Antonio, San Antonio, TX, 78249, USA.
| |
Collapse
|
14
|
Hou G, Wang X, Wang A, Yuan L, Zheng Q, Xiao H, Wang H. The role of secreted proteins in efferocytosis. Front Cell Dev Biol 2024; 11:1332482. [PMID: 38259511 PMCID: PMC10800375 DOI: 10.3389/fcell.2023.1332482] [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: 11/03/2023] [Accepted: 12/20/2023] [Indexed: 01/24/2024] Open
Abstract
The clearance of apoptotic cells known as efferocytosis is the final stage of apoptosis, and includes the recognition, phagocytosis, and degradation of apoptotic cells. The maintenance of tissue homeostasis requires the daily elimination of billions of apoptotic cells from the human body via the process of efferocytosis. Accordingly, aberrations in efferocytosis underlie a growing list of diseases, including atherosclerosis, cancer, and infections. During the initial phase of apoptosis, "Eat-Me" signals are exposed and recognized by phagocytes either directly through phagocyte receptors or indirectly through secreted proteins that function as bridge molecules that cross-link dying cells to phagocytes. Here, we set out to provide a comprehensive review of the molecular mechanisms and biological significance of secreted proteins in apoptotic cell clearance. Specifically, it focuses on how these secreted proteins act as bridging molecules to facilitate the clearance process.
Collapse
Affiliation(s)
| | | | | | | | | | - Hui Xiao
- College of Life Sciences, Shaanxi Normal University, Xi’an, China
| | - Hui Wang
- College of Life Sciences, Shaanxi Normal University, Xi’an, China
| |
Collapse
|