Katrina Volk Robertson, Alec S Rodriguez, Jean-Philippe Cartailler, Shristi Shrestha, Michael W Schleh, Kyle R Schroeder, Arianna M Valenti, Alec T Kramer, Fiona E Harrison, Alyssa H Hasty
{"title":"Knockdown of microglial iron import gene, Slc11a2, worsens cognitive function and alters microglial transcriptional landscape in a sex-specific manner in the APP/PS1 model of Alzheimer's disease.","authors":"Katrina Volk Robertson, Alec S Rodriguez, Jean-Philippe Cartailler, Shristi Shrestha, Michael W Schleh, Kyle R Schroeder, Arianna M Valenti, Alec T Kramer, Fiona E Harrison, Alyssa H Hasty","doi":"10.1186/s12974-024-03238-w","DOIUrl":"10.1186/s12974-024-03238-w","url":null,"abstract":"<p><strong>Background: </strong>Microglial cell iron load and inflammatory activation are significant hallmarks of late-stage Alzheimer's disease (AD). In vitro, microglia preferentially upregulate the iron importer, divalent metal transporter 1 (DMT1, gene name Slc11a2) in response to inflammatory stimuli, and excess iron can augment cellular inflammation, suggesting a feed-forward loop between iron import mechanisms and inflammatory signaling. However, it is not understood whether microglial iron import mechanisms directly contribute to inflammatory signaling and chronic disease in vivo. These studies determined the effects of microglial-specific knockdown of Slc11a2 on AD-related cognitive decline and microglial transcriptional phenotype.</p><p><strong>Methods: </strong>In vitro experiments and RT-qPCR were used to assess a role for DMT1 in amyloid-β-associated inflammation. To determine the effects of microglial Slc11a2 knockdown on AD-related phenotypes in vivo, triple-transgenic Cx3cr1<sup>Cre-ERT2</sup>;Slc11a2<sup>flfl</sup>;APP/PS1<sup>+or -</sup> mice were generated and administered corn oil or tamoxifen to induce knockdown at 5-6 months of age. Both sexes underwent behavioral analyses to assess cognition and memory (12-15 months of age). Hippocampal CD11b+ microglia were magnetically isolated from female mice (15-17 months) and bulk RNA-sequencing analysis was conducted.</p><p><strong>Results: </strong>DMT1 inhibition in vitro robustly decreased Aβ-induced inflammatory gene expression and cellular iron levels in conditions of excess iron. In vivo, Slc11a2<sup>KD</sup> APP/PS1 female, but not male, mice displayed a significant worsening of memory function in Morris water maze and a fear conditioning assay, along with significant hyperactivity compared to control WT and APP/PS1 mice. Hippocampal microglia from Slc11a2<sup>KD</sup> APP/PS1 females displayed significant increases in Enpp2, Ttr, and the iron-export gene, Slc40a1, compared to control APP/PS1 cells. Slc11a2<sup>KD</sup> cells from APP/PS1 females also exhibited decreased expression of markers associated with subsets of disease-associated microglia (DAMs), such as Apoe, Ctsb, Ly9, Csf1, and Hif1α.</p><p><strong>Conclusions: </strong>This work suggests a sex-specific role for microglial iron import gene Slc11a2 in propagating behavioral and cognitive phenotypes in the APP/PS1 model of AD. These data also highlight an association between loss of a DAM-like phenotype in microglia and cognitive deficits in Slc11a2<sup>KD</sup> APP/PS1 female mice. Overall, this work illuminates an iron-related pathway in microglia that may serve a protective role during disease and offers insight into mechanisms behind disease-related sex differences.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11438269/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348527","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marta Reguera-Gomez, Melissa E Munzen, Mohamed F Hamed, Claudia L Charles-Niño, Luis R Martinez
{"title":"IL-6 deficiency accelerates cerebral cryptococcosis and alters glial cell responses.","authors":"Marta Reguera-Gomez, Melissa E Munzen, Mohamed F Hamed, Claudia L Charles-Niño, Luis R Martinez","doi":"10.1186/s12974-024-03237-x","DOIUrl":"https://doi.org/10.1186/s12974-024-03237-x","url":null,"abstract":"<p><p>Cryptococcus neoformans (Cn) is an opportunistic encapsulated fungal pathogen that causes life-threatening meningoencephalitis in immunosuppressed individuals. Since IL-6 is important for blood-brain barrier support and its deficiency has been shown to facilitate Cn brain invasion, we investigated the impact of IL-6 on systemic Cn infection in vivo, focusing on central nervous system (CNS) colonization and glial responses, specifically microglia and astrocytes. IL-6 knock-out (IL-6<sup>-/-</sup>) mice showed faster mortality than C57BL/6 (Wild-type) and IL-6<sup>-/-</sup> supplemented with recombinant IL-6 (rIL-6; 40 pg/g/day) mice. Despite showing early lung inflammation but no major histological differences in pulmonary cryptococcosis progression among the experimental groups, IL-6<sup>-/-</sup> mice had significantly higher blood and brain tissue fungal burden at 7-days post infection. Exposure of cryptococci to rIL-6 in vitro increased capsule growth. In addition, IL-6<sup>-/-</sup> brains were characterized by an increased dystrophic microglia number during Cn infection, which are associated with neurodegeneration and senescence. In contrast, the brains of IL-6-producing or -supplemented mice displayed high numbers of activated and phagocytic microglia, which are related to a stronger anti-cryptococcal response or tissue repair. Likewise, culture of rIL-6 with microglia-like cells promoted high fungal phagocytosis and killing, whereas IL-6 silencing in microglia decreased fungal phagocytosis. Lastly, astrogliosis was high and moderate in infected brains removed from Wild-type and IL-6<sup>-/-</sup> supplemented with rIL-6 animals, respectively, while minimal astrogliosis was observed in IL-6<sup>-/-</sup> tissue, highlighting the potential of astrocytes in containing and combating cryptococcal infection. Our findings suggest a critical role for IL-6 in Cn CNS dissemination, neurocryptococcosis development, and host defense.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11437997/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348526","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuanjian Fang, Yibo Liu, Luxi Chen, Junjie Wang, Jiahao Zhang, Haocheng Zhang, Sixuan Tian, Anke Zhang, Jianmin Zhang, John H Zhang, Xiaoyu Wang, Jun Yu, Sheng Chen
{"title":"Cerebrospinal fluid markers of neuroinflammation and coagulation in severe cerebral edema and chronic hydrocephalus after subarachnoid hemorrhage: a prospective study.","authors":"Yuanjian Fang, Yibo Liu, Luxi Chen, Junjie Wang, Jiahao Zhang, Haocheng Zhang, Sixuan Tian, Anke Zhang, Jianmin Zhang, John H Zhang, Xiaoyu Wang, Jun Yu, Sheng Chen","doi":"10.1186/s12974-024-03236-y","DOIUrl":"https://doi.org/10.1186/s12974-024-03236-y","url":null,"abstract":"<p><strong>Background: </strong>Early severe cerebral edema and chronic hydrocephalus are the primary cause of poor prognosis in patients with subarachnoid hemorrhage (SAH). This study investigated the role of cerebrospinal fluid (CSF) inflammatory cytokines and coagulation factors in the development of severe cerebral edema and chronic hydrocephalus in patients with SAH.</p><p><strong>Methods: </strong>Patients with SAH enrolled in this study were categorized into mild and severe cerebral edema groups based on the Subarachnoid Hemorrhage Early Brain Edema Score at admission. During long-term follow-up, patients were further classified into hydrocephalus and non-hydrocephalus groups. CSF samples were collected within 48 h post-SAH, and levels of inflammatory cytokines and coagulation factors were measured. Univariate and multivariate logistic regression analyses were performed to identify independent factors associated with severe cerebral edema and chronic hydrocephalus. The correlation between inflammatory cytokines and coagulation factors was further investigated and validated in a mouse model of SAH.</p><p><strong>Results: </strong>Seventy-two patients were enrolled in the study. Factors from the extrinsic coagulation pathway and inflammatory cytokines were associated with both severe cerebral edema and chronic hydrocephalus. Coagulation products thrombin-antithrombin complexes (TAT) and fibrin, as well as inflammatory cytokines IL-1β, IL-2, IL-5, IL-7, and IL-4, were independently associated with severe cerebral edema. Additionally, Factor VII, fibrin, IL-2, IL-5, IL-12, TNF-α, and CCL-4 were independently associated with chronic hydrocephalus. A positive correlation between extrinsic coagulation factors and inflammatory cytokines was observed. In the SAH mouse model, tissue plasminogen activator was shown to alleviate neuroinflammation and cerebral edema, potentially by restoring glymphatic-meningeal lymphatic function.</p><p><strong>Conclusions: </strong>Elevated levels of inflammatory cytokines and extrinsic coagulation pathway factors in the CSF are associated with the development of early severe cerebral edema and chronic hydrocephalus following SAH. These factors are interrelated and may contribute to post-SAH glymphatic-meningeal lymphatic dysfunction.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11438016/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Valerie Joers, Benjamin C Murray, Caroline McLaughlin, Danielle Oliver, Hannah E Staley, Jazmyn Coronado, Cindy Achat-Mendes, Sanam Golshani, Sean D Kelly, Matthew Goodson, Danica Lee, Fredric P Manfredsson, Bob M Moore Ii, Malú Gámez Tansey
{"title":"Modulation of cannabinoid receptor 2 alters neuroinflammation and reduces formation of alpha-synuclein aggregates in a rat model of nigral synucleinopathy.","authors":"Valerie Joers, Benjamin C Murray, Caroline McLaughlin, Danielle Oliver, Hannah E Staley, Jazmyn Coronado, Cindy Achat-Mendes, Sanam Golshani, Sean D Kelly, Matthew Goodson, Danica Lee, Fredric P Manfredsson, Bob M Moore Ii, Malú Gámez Tansey","doi":"10.1186/s12974-024-03221-5","DOIUrl":"10.1186/s12974-024-03221-5","url":null,"abstract":"<p><p>Research into the disequilibrium of microglial phenotypes has become an area of intense focus in neurodegenerative disease as a potential mechanism that contributes to chronic neuroinflammation and neuronal loss in Parkinson's disease (PD). There is growing evidence that neuroinflammation accompanies and may promote progression of alpha-synuclein (Asyn)-induced nigral dopaminergic (DA) degeneration. From a therapeutic perspective, development of immunomodulatory strategies that dampen overproduction of pro-inflammatory cytokines from chronically activated immune cells and induce a pro-phagocytic phenotype is expected to promote Asyn removal and protect vulnerable neurons. Cannabinoid receptor-2 (CB2) is highly expressed on activated microglia and peripheral immune cells, is upregulated in the substantia nigra of individuals with PD and in mouse models of nigral degeneration. Furthermore, modulation of CB2 protects against rotenone-induced nigral degeneration; however, CB2 has not been pharmacologically and selectively targeted in an Asyn model of PD. Here, we report that 7 weeks of peripheral administration of CB2 inverse agonist SMM-189 reduced phosphorylated (pSer129) Asyn in the substantia nigra compared to vehicle treatment. Additionally, SMM-189 delayed Asyn-induced immune cell infiltration into the brain as determined by flow cytometry, increased CD68 protein expression, and elevated wound-healing-immune-mediator gene expression. Additionally, peripheral immune cells increased wound-healing non-classical monocytes and decreased pro-inflammatory classical monocytes. In vitro analysis of RAW264.7 macrophages treated with lipopolysaccharide (LPS) and SMM-189 revealed increased phagocytosis as measured by the uptake of fluorescence of pHrodo E. coli bioparticles. Together, results suggest that targeting CB2 with SMM-189 skews immune cell function toward a phagocytic phenotype and reduces toxic aggregated species of Asyn. Our novel findings demonstrate that CB2 may be a target to modulate inflammatory and immune responses in proteinopathies.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11438102/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Aberrant copper metabolism and hepatic inflammation cause neurological manifestations in a mouse model of Wilson's disease.","authors":"Jianjian Dong, Guanghai Xiang, Xiaoxue Xia, Lewen Xu, Peihua Wen, Chenchen Xu, Yin Xu, Yushuang Su, Yanze Song, Haiyang Tong, Qingjun Zhu, Yongzhu Han, Yongsheng Han, Nan Cheng, Haoyi Wang, Hong Zhou","doi":"10.1186/s12974-024-03178-5","DOIUrl":"https://doi.org/10.1186/s12974-024-03178-5","url":null,"abstract":"<p><p>Pathogenic germline mutations in the P-type copper-transporting ATPase (ATP7B) gene cause Wilson's disease (WD), a hereditary disorder characterized by disrupted copper metabolism. The Arg778Leu (R778L) mutation in exon 8 is prevalent among individuals with WD in East Asia and is associated with more severe phenotypes. In this study, we generated a WD mouse model harboring R778L mutation (R778L mice) using CRISPR/Cas9. R778L mice exhibit a range of pathological characteristics resembling those of patients with WD and the same point mutations, including aberrant copper metabolism, pathological cellular injury, inflammation, and severe hepatic fibrosis. At 3-5 months of age, these mice started to display neurological deficits in motor coordination and cognitive dysfunction, accompanied by increased expression of inflammatory cytokines in the central nervous system. Microglia in the striatum and cortex exhibit significant activation, shorter processes, and decreased branch points. However, the Cu<sup>2+</sup> levels in the brain tissue of R778L mice did not differ significantly from those of wild-type mice. Notably, inhibition of hepatic inflammation with PJ34 or siNfkb markedly alleviated the deficiencies in cognitive performance and improved locomotor activity in R778L mice. Thus, this study establishes a novel murine model to investigate the pathophysiology of WD, highlights the liver-brain crosstalk responsible for neurological manifestations in individuals with WD caused by the R778L point mutation, and demonstrates the potential of modulating liver inflammation as a therapeutic strategy for alleviating the neurological manifestations of WD.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11437830/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eleanor M Marshall, Lisa Bauer, Tessa Nelemans, Syriam Sooksawasdi Na Ayudhya, Feline Benavides, Kristina Lanko, Femke M S de Vrij, Steven A Kushner, Marion Koopmans, Debby van Riel, Barry Rockx
{"title":"Differential susceptibility of human motor neurons to infection with Usutu and West Nile virus.","authors":"Eleanor M Marshall, Lisa Bauer, Tessa Nelemans, Syriam Sooksawasdi Na Ayudhya, Feline Benavides, Kristina Lanko, Femke M S de Vrij, Steven A Kushner, Marion Koopmans, Debby van Riel, Barry Rockx","doi":"10.1186/s12974-024-03228-y","DOIUrl":"10.1186/s12974-024-03228-y","url":null,"abstract":"<p><p>West Nile virus (WNV) and Usutu virus (USUV) are closely related flaviviruses with differing capacities to cause neurological disease in humans. WNV is thought to use a transneural route of neuroinvasion along motor neurons and causes severe motor deficits. The potential for use of transneural routes of neuroinvasion by USUV has not been investigated experimentally, and evidence from the few clinical case reports of USUV-associated neuroinvasive disease is lacking. We hypothesised that, compared with WNV, USUV is less able to infect motor neurons, and therefore determined the susceptibility of human induced pluripotent stem cell (iPSC)-derived spinal cord motor neurons to infection. Both viruses could grow to high titres in iPSC-derived neural cultures. However, USUV could not productively infect motor neurons due to restriction by the antiviral response, which was not induced upon WNV infection. Inhibition of the antiviral response allowed for widespread infection and transportation of USUV along motor neurons within a compartmented culture system. These results show a stark difference in the ability of these two viruses to evade initiation of intrinsic antiviral immunity. Our data suggests that USUV cannot infect motor neurons in healthy individuals but in case of immunodeficiency may pose a risk for motor-related neurological disease and transneural invasion.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11437828/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carolin Otto, Rea Kalantzis, Dorothee Kübler-Weller, Andrea A Kühn, Tina Böld, Armin Regler, Selina Strathmeyer, Johannes Wittmann, Klemens Ruprecht, Steffen Heelemann
{"title":"Comprehensive analysis of the cerebrospinal fluid and serum metabolome in neurological diseases.","authors":"Carolin Otto, Rea Kalantzis, Dorothee Kübler-Weller, Andrea A Kühn, Tina Böld, Armin Regler, Selina Strathmeyer, Johannes Wittmann, Klemens Ruprecht, Steffen Heelemann","doi":"10.1186/s12974-024-03218-0","DOIUrl":"https://doi.org/10.1186/s12974-024-03218-0","url":null,"abstract":"<p><strong>Background: </strong>Comprehensive characterization of the metabolome in cerebrospinal fluid (CSF) and serum by Nuclear Magnetic Resonance (NMR) spectroscopy may identify biomarkers and contribute to the understanding of the pathophysiology of neurological diseases.</p><p><strong>Methods: </strong>Metabolites were determined by NMR spectroscopy in stored CSF/serum samples of 20 patients with Parkinson's disease, 25 patients with other neuro-degenerative diseases, 22 patients with cerebral ischemia, 48 patients with multiple sclerosis, and 58 control patients with normal CSF findings. The data set was analysed using descriptive and multivariate statistics, as well as machine learning models.</p><p><strong>Results: </strong>CSF glucose and lactic acid measured by NMR spectroscopy and routine clinical chemistry showed a strong correlation between both methods (glucose, R<sup>2</sup> = 0.87, n = 173; lactic acid, R<sup>2</sup> = 0.74, n = 173). NMR spectroscopy detected a total of 99 metabolites; 51 in both, CSF and serum, 16 in CSF only, and 32 in serum only. CSF concentrations of some metabolites increased with age and/or decreasing blood-brain-barrier function. Metabolite detection rates were overall similar among the different disease groups. However, in two-group comparisons, absolute metabolite levels in CSF and serum discriminated between multiple sclerosis and neurodegenerative diseases (area under the curve (AUC) = 0.96), multiple sclerosis and Parkinson's disease (AUC = 0.89), and Parkinson's disease and control patients (AUC = 0.91), as demonstrated by random forest statistical models. Orthogonal partial least square discriminant analysis using absolute metabolite levels in CSF and serum furthermore permitted separation of Parkinson's disease and neurodegenerative diseases. CSF propionic acid levels were about fourfold lower in Parkinson's disease as compared to neurodegenerative diseases.</p><p><strong>Conclusions: </strong>These findings outline the landscape of the CSF and serum metabolome in different categories of neurological diseases and identify age and blood-brain-barrier function as relevant co-factors for CSF levels of certain metabolites. Metabolome profiles as determined by NMR spectroscopy may potentially aid in differentiating groups of patients with different neurological diseases, including clinically meaningful differentiations, such as Parkinson's disease from other neurodegenerative diseases.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11430517/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142348523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jennifer Kim, Olivia Sullivan, Kristen Lee, Justin Jao, Juan Tamayo, Abdullah Muhammad Madany, Brandon Wong, Paul Ashwood, Annie Vogel Ciernia
{"title":"Repeated LPS induces training and tolerance of microglial responses across brain regions.","authors":"Jennifer Kim, Olivia Sullivan, Kristen Lee, Justin Jao, Juan Tamayo, Abdullah Muhammad Madany, Brandon Wong, Paul Ashwood, Annie Vogel Ciernia","doi":"10.1186/s12974-024-03198-1","DOIUrl":"10.1186/s12974-024-03198-1","url":null,"abstract":"<p><strong>Background: </strong>Neuroinflammation is involved in the pathogenesis of almost every central nervous system disorder. As the brain's innate immune cells, microglia fine tune their activity to a dynamic brain environment. Previous studies have shown that repeated bouts of peripheral inflammation can trigger long-term changes in microglial gene expression and function, a form of innate immune memory.</p><p><strong>Methods and results: </strong>In this study, we used multiple low-dose lipopolysaccharide (LPS) injections in adult mice to study the acute cytokine, transcriptomic, and microglia morphological changes that contribute to the formation of immune memory in the frontal cortex, hippocampus, and striatum, as well as the long-term effects of these changes on behavior. Training and tolerance of gene expression was shared across regions, and we identified 3 unique clusters of DEGs (2xLPS-sensitive, 4xLPS-sensitive, LPS-decreased) enriched for different biological functions. 2xLPS-sensitive DEG promoters were enriched for binding sites for IRF and NFkB family transcription factors, two key regulators of innate immune memory. We quantified shifts in microglia morphological populations and found that while the proportion of ramified and rod-like microglia mostly remained consistent within brain regions and sexes with LPS treatment, there was a shift from ameboid towards hypertrophic morphological states across immune memory states and a dynamic emergence and resolution of events of microglia aligning end-to-end with repeated LPS.</p><p><strong>Conclusions: </strong>Together, findings support the dynamic regulation of microglia during the formation of immune memories in the brain and support future work to exploit this model in brain disease contexts.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11414187/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142289408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A comprehensive review of AAV-mediated strategies targeting microglia for therapeutic intervention of neurodegenerative diseases.","authors":"Livia Zhou, Yafeng Wang, Yiran Xu, Yaodong Zhang, Changlian Zhu","doi":"10.1186/s12974-024-03232-2","DOIUrl":"https://doi.org/10.1186/s12974-024-03232-2","url":null,"abstract":"<p><p>Neurodegenerative diseases pose a significant health burden globally, with limited treatment options available. Among the various cell types involved in the pathogenesis of these disorders, microglia, the resident immune cells of the central nervous system, play a pivotal role. Dysregulated microglial activation contributes to neuroinflammation and neuronal damage, making them an attractive target for therapeutic intervention. Adeno-associated virus (AAV) vectors have emerged as powerful tools for delivering therapeutic genes to specific cell types in the central nervous system with remarkable precision and safety. In the current review, we discuss the strategies employed to achieve selective transduction of microglia, including the use of cell-specific promoters, engineered capsids, and microRNA (miRNA) strategies. Additionally, we address the challenges and future directions in the development of AAV-based therapies targeting microglia. Overall, AAV-mediated targeting of microglia holds promise as a novel therapeutic approach for neurodegenerative diseases, offering the potential to modify disease progression and improve patient outcomes.</p>","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11414267/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142289407","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Peiyu Bian, Haijun Zhang, Chuantao Ye, Chuanyu Luo, Hong Jiang, Yuan Wang, Yangchao Dong, Jing Yang, Fanglin Zhang, Xiaoming Wang, Ying Zhang, Zhansheng Jia, Yingfeng Lei
{"title":"GAS6 as a potential target to alleviate neuroinflammation during Japanese encephalitis in mouse models","authors":"Peiyu Bian, Haijun Zhang, Chuantao Ye, Chuanyu Luo, Hong Jiang, Yuan Wang, Yangchao Dong, Jing Yang, Fanglin Zhang, Xiaoming Wang, Ying Zhang, Zhansheng Jia, Yingfeng Lei","doi":"10.1186/s12974-024-03225-1","DOIUrl":"https://doi.org/10.1186/s12974-024-03225-1","url":null,"abstract":"Viral encephalitis is characterized by inflammation of the brain parenchyma caused by a variety of viruses, among which the Japanese encephalitis (JE) virus (JEV) is a typical representative arbovirus. Neuronal death, neuroinflammation, and breakdown of the blood brain barrier (BBB) constitute vicious circles of JE progression. Currently, there is no effective therapy to prevent this damage. Growth arrest specific gene 6 (GAS6) is a secreted growth factor that binds to the TYRO3, AXL, and MERTK (TAM) family of receptor tyrosine kinases and has been demonstrated to participate in neuroprotection and suppression of inflammation in many central nervous system (CNS) diseases which has great potential for JE intervention. In this study, we found that GAS6 expression in the brain was decreased and was reversely correlated with viral load and neuronal loss. Mice with GAS6/TAM signalling deficiency showed higher mortality and accelerated neuroinflammation during peripheral JEV infection, accompanied by BBB breakdown. GAS6 directly promoted the expression of tight junction proteins in bEnd.3 cells and strengthened BBB integrity, partly via AXL. Mice administered GAS6 were more resistant to JEV infection due to increased BBB integrity, as well as decreased viral load and neuroinflammation. Thus, targeted GAS6 delivery may represent a strategy for the prevention and treatment of JE especially in patients with impaired BBB.","PeriodicalId":16577,"journal":{"name":"Journal of Neuroinflammation","volume":null,"pages":null},"PeriodicalIF":9.3,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}