1
|
Cabral-França T, Cruz FF, Silva PC, Pannain VLN, Fernandes A, Eulálio JMR, Paiva MM, Macedo-Ramos H, Manso JEF, Baetas-da-Cruz W. Hippocampal Microglia Activation Induced by Acute Pancreatic Injury in Rats. Dig Dis Sci 2024; 69:148-160. [PMID: 37957410 DOI: 10.1007/s10620-023-08167-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 10/19/2023] [Indexed: 11/15/2023]
Abstract
BACKGROUND Acute pancreatitis is an inflammation of the pancreatic glandular parenchyma that causes injury with or without the destruction of pancreatic acini. Clinical and experimental evidence suggest that certain systemic proinflammatory mediators may be responsible for initiating the fundamental mechanisms involved in microglial reactivity. Here, we investigated the possible repercussions of acute pancreatitis (AP) on the production of inflammatory mediators in the brain parenchyma focusing on microglial activation in the hippocampus. METHODS The acute pancreatic injury in rats was induced by a pancreas ligation surgical procedure (PLSP) on the splenic lobe, which corresponds to approximately 10% of total mass of the pancreas. Blood samples were collected via intracardiac puncture for the measurement of serum amylase. After euthanasia, frozen or paraffin-embedded brains and pancreas were analyzed using qRT-PCR or immunohistochemistry, respectively. RESULTS Immunohistochemistry assays showed a large number of Iba1 and PU.1-positive cells in the CA1, CA3, and dentate gyrus (DG) regions of the hippocampus of the PLSP group. TNF-α mRNA expression was significantly higher in the brain from PLSP group. NLRP3 inflammasome expression was found to be significantly increased in the pancreas and brain of rats of the PLSP group. High levels of BNDF mRNA were found in the rat brain of PLSP group. In contrast, NGF mRNA levels were significantly higher in the control group versus PLSP group. CONCLUSION Our findings suggest that AP has the potential to induce morphological changes in microglia consistent with an activated phenotype.
Collapse
Affiliation(s)
- Tamires Cabral-França
- Postgraduate Program in Surgical Science, Department of Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Surgery, Centre for Experimental Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Translational Laboratory in Molecular Physiology, Department of Surgery, School of Medicine, Centre for Experimental Surgery, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fernanda Ferreira Cruz
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo Cesar Silva
- Department of Surgery, Centre for Experimental Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Vera Lucia Nunes Pannain
- Postgraduate Program in Surgical Science, Department of Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Pathology, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Arlete Fernandes
- Laboratory of Pulmonary Investigation, Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Pathology, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - José Marcus Raso Eulálio
- Postgraduate Program in Surgical Science, Department of Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Surgery, Centre for Experimental Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Hugo Macedo-Ramos
- Translational Laboratory in Molecular Physiology, Department of Surgery, School of Medicine, Centre for Experimental Surgery, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jose Eduardo Ferreira Manso
- Postgraduate Program in Surgical Science, Department of Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
- Department of Surgery, Centre for Experimental Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Wagner Baetas-da-Cruz
- Postgraduate Program in Surgical Science, Department of Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
- Department of Surgery, Centre for Experimental Surgery, School of Medicine, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
- Translational Laboratory in Molecular Physiology, Department of Surgery, School of Medicine, Centre for Experimental Surgery, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
- Laboratório Translacional em Fisiologia Molecular, Faculdade de Medicina, Centro de Cirurgia Experimental, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho 373, CCS, Bloco J, 2º and, Rio de Janeiro, RJ, 21941-902, Brazil.
| |
Collapse
|
2
|
Salmani H, Hosseini M, Nabi MM, Samadi-Noshahr Z, Baghcheghi Y, Sadeghi M. Exacerbated immune response of the brain to peripheral immune challenge in post-septic mice. Brain Res Bull 2022; 185:74-85. [PMID: 35523357 DOI: 10.1016/j.brainresbull.2022.04.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 04/24/2022] [Accepted: 04/26/2022] [Indexed: 11/02/2022]
Abstract
BACKGROUND Mounting evidence indicates that sepsis can induce long-lasting brain dysfunction. Recently, it has been proposed that the brain may become more sensitive to systemic inflammation if microglial cells are already primed. Microglial priming has been demonstrated in aging, traumatic brain injury, and neurodegenerative diseases. There is evidence suggesting that systemic inflammation may also prime microglia. This study aimed to investigate the brain's response to a second immune challenge in sepsis survivors and the possible role of microglial priming. METHODS Adult BALB/c mice were intraperitoneally (ip) injected with 5 mg/kg lipopolysaccharide (LPS) for sepsis induction. One month later, mice received a second immune challenge (LPS, 0.33 mg/kg). A cohort of mice was sacrificed 2 h post-LPS injection to measure inflammatory mediators mRNA expression. The second cohort of mice was tested on a battery of behavioral tests and then sacrificed, and brain tissues were removed for biochemical analyses. RESULTS Results showed that in septic mice, secondary LPS challenge induced heightened neuroinflammation compared to the control mice, as evident by a significant increase of IL-1β, TNF-α, and iNOS mRNA expression. In the immunochallenged septic mice, the anti-inflammatory cytokine IL-10 expression was also significantly increased compared to the control mice. Sepsis induction significantly disrupted the recognition ability in the novel object recognition, but the second immune challenge had no significant effect. However, immunochallenged septic mice exhibited more anxiety-like behavior in the marble burying task and intensive depressive-like behavior in the forced swim test. Additionally, the second immune challenge reduced arginase-1 levels in septic but not control mice. On the other hand, CIITA levels were increased more significantly in the LPS injected control mice compared to septic mice. Neither sepsis nor the second immune challenge significantly affected inhibitory avoidance behavior and Aβ1-42 levels in brain tissue. CONCLUSION Our finding suggests that low-grade immune challenge can induce exacerbated behavioral change and exaggerated inflammatory response in the brain of post-septic mice.
Collapse
Affiliation(s)
- Hossein Salmani
- Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Student Research Committee, Jiroft University of Medical Sciences, Jiroft, Iran.
| | - Mahmoud Hosseini
- Division of Neurocognitive Sciences, Psychiatry and Behavioral Sciences Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; Applied Biomedical Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
| | - Mohammad Mahdi Nabi
- Mashhad Branch, Razi Vaccine and Serum Research Institute, Agricultural Research, Education and Extension Organization (AREEO), Mashhad, Iran; Department of Animal Science, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
| | | | - Yousef Baghcheghi
- Student Research Committee, Jiroft University of Medical Sciences, Jiroft, Iran.
| | - Mostafa Sadeghi
- Department of Animal Science, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran.
| |
Collapse
|
3
|
Recasens M, Almolda B, Pérez-Clausell J, Campbell IL, González B, Castellano B. Chronic exposure to IL-6 induces a desensitized phenotype of the microglia. J Neuroinflammation 2021; 18:31. [PMID: 33482848 DOI: 10.1186/s12974-020-02063-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 12/16/2020] [Indexed: 12/14/2022] Open
Abstract
Background When the homeostasis of the central nervous system (CNS) is altered, microglial cells become activated displaying a wide range of phenotypes that depend on the specific site, the nature of the activator, and particularly the microenvironment generated by the lesion. Cytokines are important signals involved in the modulation of the molecular microenvironment and hence play a pivotal role in orchestrating microglial activation. Among them, interleukin-6 (IL-6) is a pleiotropic cytokine described in a wide range of pathological conditions as a potent inducer and modulator of microglial activation, but with contradictory results regarding its detrimental or beneficial functions. The objective of the present study was to evaluate the effects of chronic IL-6 production on the immune response associated with CNS-axonal anterograde degeneration. Methods The perforant pathway transection (PPT) paradigm was used in transgenic mice with astrocyte-targeted IL6-production (GFAP-IL6Tg). At 2, 3, 7, 14, and 21 days post-lesion, the hippocampal areas were processed for immunohistochemistry, flow cytometry, and protein microarray. Results An increase in the microglia/macrophage density was observed in GFAP-IL6Tg animals in non-lesion conditions and at later time-points after PPT, associated with higher microglial proliferation and a major monocyte/macrophage cell infiltration. Besides, in homeostasis, GFAP-IL6Tg showed an environment usually linked with an innate immune response, with more perivascular CD11b+/CD45high/MHCII+/CD86+ macrophages, higher T cell infiltration, and higher IL-10, IL-13, IL-17, and IL-6 production. After PPT, WT animals show a change in microglia phenotype expressing MHCII and co-stimulatory molecules, whereas transgenic mice lack this shift. This lack of response in the GFAP-IL6Tg was associated with lower axonal sprouting. Conclusions Chronic exposure to IL-6 induces a desensitized phenotype of the microglia. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-020-02063-1.
Collapse
|
4
|
Nomura A, Noto D, Murayama G, Chiba A, Miyake S. Unique primed status of microglia under the systemic autoimmune condition of lupus-prone mice. Arthritis Res Ther 2019; 21:303. [PMID: 31888754 PMCID: PMC6936062 DOI: 10.1186/s13075-019-2067-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 11/25/2019] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of various autoantibodies. This disease causes disabling neuropsychiatric symptoms even in the absence of apparent inflammation in the central nervous system (CNS), but the mechanisms involved remain unknown. Innate immune-mediated inflammation has attracted attention as a pathogenic mechanism in neuropsychiatric diseases. METHODS We investigated the CNS of lupus-prone mice focusing on innate immunity. Three strains of lupus-prone mice, FcγRIIB-/-Yaa, an F1 hybrid of NZB and NZW (NZB/NZW) mice, and MRL/Faslpr (MRL/lpr) mice were used to analyze CNS immunopathology. RESULTS Flow cytometry analysis demonstrated the numbers of brain CD45+ cells were increased compared with controls in lupus-prone mice. Upregulation of MHC class I and PDCA1 was observed in microglia and CD11b+ myeloid cells of lupus-prone mice, indicating they were activated in response to interferons (IFN). Microglial gene expression analysis of FcγRIIB-/-Yaa mice revealed the upregulation of IFN-responsive genes and inflammation-related genes including Axl, Clec7a, and Itgax, which were previously reported in neurodegenerative conditions and primed conditions. Upregulated chemokine gene expressions including Ccl5 and Cxcl10 were concurrent with increased numbers of T cells and monocytes, especially Ly6Clo monocytes in the CNS. Upregulation of Axl, Clec7a, Itgax, Ccl5, and Cxcl10 was also observed in NZB/NZW mice, indicating common lupus pathology. The primed status of microglia in FcγRIIB-/-Yaa mice was also demonstrated by morphological changes such as enlarged cell bodies with hypertrophic processes, and hyperreactivity to lipopolysaccharide. Immunohistochemistry of FcγRIIB-/-Yaa mice indicated reactive responses of astrocytes and vascular endothelium. Behavioral studies of FcγRIIB-/-Yaa mice revealed depressive-like behavior and heat hyperalgesia in the forced swim test and the tail-flick test, respectively. CONCLUSIONS Our data indicated that microglia in lupus exhibit a unique primed phenotype characterized by the upregulated expressions of neurodegeneration-related genes and IFN-responsive genes. Interaction with peripheral cells and brain resident cells was presumed to orchestrate neuroinflammation. Targeting innate immune cells, such as microglia and monocytes, may be a promising therapeutic approach for neuropsychiatric SLE.
Collapse
Affiliation(s)
- Atsushi Nomura
- Department of Immunology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Daisuke Noto
- Department of Immunology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Goh Murayama
- Department of Immunology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.,Department of Internal Medicine and Rheumatology, Juntendo University School of Medicine, Tokyo, Japan
| | - Asako Chiba
- Department of Immunology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Sachiko Miyake
- Department of Immunology, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
| |
Collapse
|