1
|
Bellingacci L, Canonichesi J, Mancini A, Parnetti L, Di Filippo M. Cytokines, synaptic plasticity and network dynamics: a matter of balance. Neural Regen Res 2023; 18:2569-2572. [PMID: 37449591 DOI: 10.4103/1673-5374.371344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/18/2023] Open
Abstract
The modern view of the immune system as a sensitizing and modulating machinery of the central nervous system is now well recognized. However, the specific mechanisms underlying this fine crosstalk have yet to be fully disentangled. To control cognitive function and behavior, the two systems are engaged in a subtle interacting act. In this scenario, a dual action of pro-inflammatory cytokines in the modulation of brain network connections is emerging. Pro-inflammatory cytokines are indeed required to express physiological plasticity in the hippocampal network while being detrimental when over-expressed during uncontrolled inflammatory processes. In this dynamic equilibrium, synaptic functioning and the performance of neural networks are ensured by maintaining an appropriate balance between pro- and anti-inflammatory molecules in the central nervous system microenvironment.
Collapse
Affiliation(s)
- Laura Bellingacci
- Section of Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| | - Jacopo Canonichesi
- Section of Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| | - Andrea Mancini
- Section of Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| | - Lucilla Parnetti
- Section of Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| | - Massimiliano Di Filippo
- Section of Neurology, Department of Medicine and Surgery, University of Perugia, Perugia, Italy
| |
Collapse
|
2
|
Su C, Miao J, Guo J. The relationship between TGF-β1 and cognitive function in the brain. Brain Res Bull 2023; 205:110820. [PMID: 37979810 DOI: 10.1016/j.brainresbull.2023.110820] [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: 09/13/2023] [Revised: 11/05/2023] [Accepted: 11/15/2023] [Indexed: 11/20/2023]
Abstract
Transforming growth factor-β1 (TGF-β1), a multifunctional cytokine, plays a pivotal role in synaptic formation, plasticity, and neurovascular unit regulation. This review highlights TGF-β1's potential impact on cognitive function, particularly in the context of neurodegenerative disorders. However, despite the growing body of evidence, a comprehensive understanding of TGF-β1's precise role remains elusive. Further research is essential to unravel the complex mechanisms through which TGF-β1 influences cognitive function and to explore therapeutic avenues for targeting TGF-β1 in neurodegenerative conditions. This investigation sheds light on TGF-β1's contribution to cognitive function and offers prospects for innovative treatments and interventions. This review delves into the intricate relationship between TGF-β1 and cognitive function.
Collapse
Affiliation(s)
- Chen Su
- Department of Neurology, First Hospital of Shanxi Medical University, Taiyuan, Shanxi Province 030000, China
| | - Jie Miao
- Department of Neurology, First Hospital of Shanxi Medical University, Taiyuan, Shanxi Province 030000, China
| | - Junhong Guo
- Department of Neurology, First Hospital of Shanxi Medical University, Taiyuan, Shanxi Province 030000, China.
| |
Collapse
|
3
|
Raschick M, Richter A, Fischer L, Knopf L, Schult A, Yakupov R, Behnisch G, Guttek K, Düzel E, Dunay IR, Seidenbecher CI, Schraven B, Reinhold D, Schott BH. Plasma concentrations of anti-inflammatory cytokine TGF-β are associated with hippocampal structure related to explicit memory performance in older adults. J Neural Transm (Vienna) 2023:10.1007/s00702-023-02638-1. [PMID: 37115329 PMCID: PMC10374779 DOI: 10.1007/s00702-023-02638-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/19/2023] [Indexed: 04/29/2023]
Abstract
Human cognitive abilities, and particularly hippocampus-dependent memory performance typically decline with increasing age. Immunosenescence, the age-related disintegration of the immune system, is increasingly coming into the focus of research as a considerable factor contributing to cognitive decline. In the present study, we investigated potential associations between plasma levels of pro- and anti-inflammatory cytokines and learning and memory performance as well as hippocampal anatomy in young and older adults. Plasma concentrations of the inflammation marker CRP as well as the pro-inflammatory cytokines IL-6 and TNF-α and the anti-inflammatory cytokine TGF-β1 were measured in 142 healthy adults (57 young, 24.47 ± 4.48 years; 85 older, 63.66 ± 7.32 years) who performed tests of explicit memory (Verbal Learning and Memory Test, VLMT; Wechsler Memory Scale, Logical Memory, WMS) with an additional delayed recall test after 24 h. Hippocampal volumetry and hippocampal subfield segmentation were performed using FreeSurfer, based on T1-weighted and high-resolution T2-weighted MR images. When investigating the relationship between memory performance, hippocampal structure, and plasma cytokine levels, we found that TGF-β1 concentrations were positively correlated with the volumes of the hippocampal CA4-dentate gyrus region in older adults. These volumes were in turn positively associated with better performance in the WMS, particularly in the delayed memory test. Our results support the notion that endogenous anti-inflammatory mechanisms may act as protective factors in neurocognitive aging.
Collapse
Affiliation(s)
- Matthias Raschick
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
| | - Anni Richter
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
- Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Larissa Fischer
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Lea Knopf
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
| | - Annika Schult
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
| | - Renat Yakupov
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
- Institute of Cognitive Neurology and Dementia Research, Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Gusalija Behnisch
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
| | - Karina Guttek
- Institute of Molecular and Clinical Immunology, Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Emrah Düzel
- Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
- Institute of Cognitive Neurology and Dementia Research, Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Ildiko Rita Dunay
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
- Institute for Inflammation and Neurodegeneration, Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Health Campus Immunology, Infectiology and Inflammation (GC-I3), Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Constanze I Seidenbecher
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany
- Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany
| | - Burkhart Schraven
- Institute of Molecular and Clinical Immunology, Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Health Campus Immunology, Infectiology and Inflammation (GC-I3), Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Center for Health and Medical Prevention (CHaMP), Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Dirk Reinhold
- Institute of Molecular and Clinical Immunology, Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Health Campus Immunology, Infectiology and Inflammation (GC-I3), Medical Faculty, Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
- Center for Health and Medical Prevention (CHaMP), Otto-Von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Björn H Schott
- Leibniz Institute for Neurobiology, Brenneckestr. 6, 39118, Magdeburg, Germany.
- Center for Behavioral Brain Sciences (CBBS), Magdeburg, Germany.
- Department of Psychiatry and Psychotherapy, University Medical Center, Göttingen, Germany.
- German Center for Neurodegenerative Diseases (DZNE), Göttingen, Germany.
| |
Collapse
|
4
|
Varghese N, Morrison B. Partial Depletion of Microglia Attenuates Long-Term Potentiation Deficits following Repeated Blast Traumatic Brain Injury in Organotypic Hippocampal Slice Cultures. J Neurotrauma 2023; 40:547-560. [PMID: 36508265 PMCID: PMC10081725 DOI: 10.1089/neu.2022.0284] [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] [Indexed: 12/14/2022] Open
Abstract
Blast-induced traumatic brain injury (bTBI) has been a health concern in both military and civilian populations due to recent military and geopolitical conflicts. Military service members are frequently exposed to repeated bTBI throughout their training and deployment. Our group has previously reported compounding functional deficits as a result of increased number of blast exposures. In this study, we further characterized the decrease in long-term potentiation (LTP) by varying the blast injury severity and the inter-blast interval between two blast exposures. LTP deficits were attenuated with increasing inter-blast intervals. We also investigated changes in microglial activation; expression of CD68 was increased and expression of CD206 was decreased after multiple blast exposures. Expression of macrophage inflammatory protein (MIP)-1α, interleukin (IL)-1β, monocyte chemoattractant protein (MCP)-1, interferon gamma-inducible protein (IP)-10, and regulated on activation, normal T cell expressed and secreted (RANTES) increased, while expression of IL-10 decreased in the acute period after both single and repeated bTBI. By partially depleting microglia prior to injury, LTP deficits after injury were significantly reduced. Treatment with the novel drug, MW-189, prevented LTP deficits when administered immediately following a repeated bTBI and even when administered only for an acute period (24 h) between two blast injuries. These findings could inform the development of therapeutic strategies to treat the neurological deficits of repeated bTBI suggesting that microglia play a major role in functional neuronal deficits and may be a viable therapeutic target to lessen the neurophysiological deficits after bTBI.
Collapse
Affiliation(s)
- Nevin Varghese
- Department of Biomedical Engineering, Columbia University, New York, New York, USA
| | - Barclay Morrison
- Department of Biomedical Engineering, Columbia University, New York, New York, USA
| |
Collapse
|
5
|
Ghaderi S, Komaki A, Salehi I, Basir Z, Rashno M. Possible mechanisms involved in the protective effects of chrysin against lead-induced cognitive decline: An in vivo study in a rat model. Biomed Pharmacother 2023; 157:114010. [PMID: 36402029 DOI: 10.1016/j.biopha.2022.114010] [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: 09/17/2022] [Revised: 11/04/2022] [Accepted: 11/11/2022] [Indexed: 11/17/2022] Open
Abstract
Lead (Pb) is a highly poisonous environmental pollutant that can induce cognitive decline. Chrysin, a natural flavonoid compound, has anti-oxidative, anti-inflammatory, and neuroprotective properties in different neurodegenerative disorders. The present study was designed to examine the putative effects of chrysin against Pb-induced cognitive impairment and the possible involved mechanisms. Adult male Wistar rats were exposed to Pb acetate (500 ppm in standard drinking water) either alone or in combination with daily oral administration of chrysin (30 mg/kg) for eight consecutive weeks. During the eight-week period of the study, the cognitive capacity of the rats was evaluated by employing both novel object recognition and passive avoidance tests. On day 56, hippocampal synaptic plasticity (long-term potentiation; LTP) was recorded in perforant path-dentate gyrus (PP-DG) synapses to assess field excitatory postsynaptic potentials (fEPSPs) slope and population spike (PS) amplitude. Subsequently, pro- and anti-inflammatory cytokines and histological changes were evaluated in the cerebral cortex and hippocampus of the rats. Moreover, Pb levels in blood and brain tissues were assessed. The results showed that Pb exposure causes cognitive decline, inhibition of hippocampal LTP induction, imbalance of pro- and anti-inflammatory cytokines, enhancement of Pb levels in blood and brain tissues, and neuronal loss. However, chrysin treatment improved cognitive dysfunction, ameliorated hippocampal LTP impairment, modulated inflammatory status, reduced Pb concentration, and prevented neuronal loss in the Pb-exposed rats. The results suggest that chrysin alleviates Pb-induced cognitive deficit, possibly through mitigation of hippocampal synaptic dysfunction, modulation of inflammatory status, reduction of Pb concentration, and prevention of neuronal loss.
Collapse
Affiliation(s)
- Shahab Ghaderi
- Department of Neuroscience, School of Science and Advanced Technologies in Medicine, Hamadan University of Medical Sciences, Hamadan, Iran; Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Alireza Komaki
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Iraj Salehi
- Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran; Asadabad School of Medical Sciences, Asadabad, Iran
| | - Zahra Basir
- Department of Basic Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
| | - Masome Rashno
- Asadabad School of Medical Sciences, Asadabad, Iran; Student Research Committee, Asadabad School of Medical Sciences, Asadabad, Iran.
| |
Collapse
|
6
|
Stone TW, Clanchy FIL, Huang YS, Chiang NY, Darlington LG, Williams RO. An integrated cytokine and kynurenine network as the basis of neuroimmune communication. Front Neurosci 2022; 16:1002004. [PMID: 36507331 PMCID: PMC9729788 DOI: 10.3389/fnins.2022.1002004] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 10/31/2022] [Indexed: 11/25/2022] Open
Abstract
Two of the molecular families closely associated with mediating communication between the brain and immune system are cytokines and the kynurenine metabolites of tryptophan. Both groups regulate neuron and glial activity in the central nervous system (CNS) and leukocyte function in the immune system, although neither group alone completely explains neuroimmune function, disease occurrence or severity. This essay suggests that the two families perform complementary functions generating an integrated network. The kynurenine pathway determines overall neuronal excitability and plasticity by modulating glutamate receptors and GPR35 activity across the CNS, and regulates general features of immune cell status, surveillance and tolerance which often involves the Aryl Hydrocarbon Receptor (AHR). Equally, cytokines and chemokines define and regulate specific populations of neurons, glia or immune system leukocytes, generating more specific responses within restricted CNS regions or leukocyte populations. In addition, as there is a much larger variety of these compounds, their homing properties enable the superimposition of dynamic variations of cell activity upon local, spatially limited, cell populations. This would in principle allow the targeting of potential treatments to restricted regions of the CNS. The proposed synergistic interface of 'tonic' kynurenine pathway affecting baseline activity and the superimposed 'phasic' cytokine system would constitute an integrated network explaining some features of neuroimmune communication. The concept would broaden the scope for the development of new treatments for disorders involving both the CNS and immune systems, with safer and more effective agents targeted to specific CNS regions.
Collapse
Affiliation(s)
- Trevor W. Stone
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom,*Correspondence: Trevor W. Stone,
| | - Felix I. L. Clanchy
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Yi-Shu Huang
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - Nien-Yi Chiang
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| | - L. Gail Darlington
- Department of Internal Medicine, Ashtead Hospital, Ashtead, United Kingdom
| | - Richard O. Williams
- The Kennedy Institute of Rheumatology, NDORMS, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
7
|
Hikosaka M, Kawano T, Wada Y, Maeda T, Sakurai T, Ohtsuki G. Immune-Triggered Forms of Plasticity Across Brain Regions. Front Cell Neurosci 2022; 16:925493. [PMID: 35978857 PMCID: PMC9376917 DOI: 10.3389/fncel.2022.925493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 06/16/2022] [Indexed: 01/03/2023] Open
Abstract
Immune cells play numerous roles in the host defense against the invasion of microorganisms and pathogens, which induces the release of inflammatory mediators (e.g., cytokines and chemokines). In the CNS, microglia is the major resident immune cell. Recent efforts have revealed the diversity of the cell types and the heterogeneity of their functions. The refinement of the synapse structure was a hallmark feature of the microglia, while they are also involved in the myelination and capillary dynamics. Another promising feature is the modulation of the synaptic transmission as synaptic plasticity and the intrinsic excitability of neurons as non-synaptic plasticity. Those modulations of physiological properties of neurons are considered induced by both transient and chronic exposures to inflammatory mediators, which cause behavioral disorders seen in mental illness. It is plausible for astrocytes and pericytes other than microglia and macrophage to induce the immune-triggered plasticity of neurons. However, current understanding has yet achieved to unveil what inflammatory mediators from what immune cells or glia induce a form of plasticity modulating pre-, post-synaptic functions and intrinsic excitability of neurons. It is still unclear what ion channels and intracellular signaling of what types of neurons in which brain regions of the CNS are involved. In this review, we introduce the ubiquitous modulation of the synaptic efficacy and the intrinsic excitability across the brain by immune cells and related inflammatory cytokines with the mechanism for induction. Specifically, we compare neuro-modulation mechanisms by microglia of the intrinsic excitability of cerebellar Purkinje neurons with cerebral pyramidal neurons, stressing the inverted directionality of the plasticity. We also discuss the suppression and augmentation of the extent of plasticity by inflammatory mediators, as the meta-plasticity by immunity. Lastly, we sum up forms of immune-triggered plasticity in the different brain regions with disease relevance. Together, brain immunity influences our cognition, sense, memory, and behavior via immune-triggered plasticity.
Collapse
|
8
|
Jiang S, Wang YQ, Tang Y, Lu X, Guo D. Environmental Enrichment Protects Against Sepsis-Associated Encephalopathy-Induced Learning and Memory Deficits by Enhancing the Synthesis and Release of Vasopressin in the Supraoptic Nucleus. J Inflamm Res 2022; 15:363-379. [PMID: 35079222 PMCID: PMC8776728 DOI: 10.2147/jir.s345108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 01/07/2022] [Indexed: 12/28/2022] Open
Abstract
Background As a severe complication of sepsis, sepsis-associated encephalopathy (SAE) usually manifests as impaired learning and memory ability in survivors. Previous studies have reported that environmental enrichment (EE) can increase the learning and memory ability in different brain injury models. However, there has been no research on the possible positive effect of EE on SAE. Aim The present study aimed to test the effect of EE on SAE-induced impairment of learning and memory and its related mechanisms. Methods A Morris water maze test (MWM) was used to evaluate the learning and memory ability of SAE rats that received EE housing or not. The expression of vasopressin (VP) was assessed using immunofluorescence microscopy and enzyme-linked immunosorbent assays (ELISAs). The synthesis of VP in the supraoptic nucleus (SON) was determined using quantitative real-time reverse transcription-PCR analysis. Moreover, inflammatory markers and brain-derived neurotrophic factor (BDNF) were detected using ELISA. Results The results showed that SAE induced a decreased learning and memory ability, while EE reversed this impairment. EE also enhanced the synthesis and secretion of VP in the SON. Blocking the action of VP in the hippocampus interrupted the EE-induced amelioration of learning and memory impairment. Moreover, EE induced changes to the levels of BDNF and cytokines in the hippocampus and these effects were mediated by VP binding to the VP receptor 1a. Conclusion Our findings demonstrated that the enhanced synthesis and secretion of VP in the SON are a key determinant responsible for EE-induced alleviation of learning and memory deficits caused by SAE.
Collapse
Affiliation(s)
- Shan Jiang
- Department of Rehabilitation Medicine, the China-Japan Friendship Hospital, Beijing, 100029, People’s Republic of China
- Correspondence: Shan Jiang, Department of Rehabilitation Medicine, the China-Japan Friendship Hospital, No. 2 Ying Hua Yuan East Street, Beijing, 100029, People’s Republic of China, Tel +86 10 84205288, Fax +86 10 64217749, Email
| | - Yong-Qiang Wang
- Department of Ophthalmology, the Sunshine Union Hospital, Weifang, Shandong, 261071, People’s Republic of China
| | - Yifei Tang
- Department of Rehabilitation Medicine, the China-Japan Friendship Hospital, Beijing, 100029, People’s Republic of China
| | - Xi Lu
- Department of Rehabilitation Medicine, the China-Japan Friendship Hospital, Beijing, 100029, People’s Republic of China
| | - Dan Guo
- Department of Rehabilitation Medicine, the China-Japan Friendship Hospital, Beijing, 100029, People’s Republic of China
| |
Collapse
|
9
|
Ding Z, Guo S, Luo L, Zheng Y, Gan S, Kang X, Wu X, Zhu S. Emerging Roles of Microglia in Neuro-vascular Unit: Implications of Microglia-Neurons Interactions. Front Cell Neurosci 2021; 15:706025. [PMID: 34712121 PMCID: PMC8546170 DOI: 10.3389/fncel.2021.706025] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 09/10/2021] [Indexed: 12/20/2022] Open
Abstract
Microglia, which serve as the defensive interface of the nervous system, are activated in many neurological diseases. Their role as immune responding cells has been extensively studied in the past few years. Recent studies have demonstrated that neuronal feedback can be shaped by the molecular signals received and sent by microglia. Altered neuronal activity or synaptic plasticity leads to the release of various communication messages from neurons, which in turn exert effects on microglia. Research on microglia-neuron communication has thus expanded from focusing only on neurons to the neurovascular unit (NVU). This approach can be used to explore the potential mechanism of neurovascular coupling across sophisticated receptor systems and signaling cascades in health and disease. However, it remains unclear how microglia-neuron communication happens in the brain. Here, we discuss the functional contribution of microglia to synapses, neuroimmune communication, and neuronal activity. Moreover, the current state of knowledge of bidirectional control mechanisms regarding interactions between neurons and microglia are reviewed, with a focus on purinergic regulatory systems including ATP-P2RY12R signaling, ATP-adenosine-A1Rs/A2ARs, and the ATP-pannexin 1 hemichannel. This review aims to organize recent studies to highlight the multifunctional roles of microglia within the neural communication network in health and disease.
Collapse
Affiliation(s)
- Zhe Ding
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Shaohui Guo
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Lihui Luo
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Yueying Zheng
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Shuyuan Gan
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xianhui Kang
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaomin Wu
- Department of Anesthesiology, Zhejiang Provincial People's Hospital, People's Hospital of Hangzhou Medical College, Hangzhou, China
| | - Shengmei Zhu
- Department of Anesthesiology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| |
Collapse
|
10
|
Levin SG, Pershina EV, Bugaev-Makarovskiy NA, Chernomorets IY, Konakov MV, Arkhipov VI. Why Do Levels Of Anti-inflammatory Cytokines Increase During Memory Acquisition? Neuroscience 2021; 473:159-169. [PMID: 34418518 DOI: 10.1016/j.neuroscience.2021.08.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 07/14/2021] [Accepted: 08/12/2021] [Indexed: 12/24/2022]
Abstract
The role of anti-inflammatory cytokines in the mechanisms of learning and memory, modulation of synaptic plasticity in the mammalian brain has not received sufficient attention. These issues are discussed in this review, and among the many cytokines, attention is paid to the most studied in this respect IL-10, IL-4, IL-13 and TGF-β. The level of anti-inflammatory cytokines in the brain tends to increase during memory acquisition, but the significance of such an increase is unclear. We hypothesize that anti-inflammatory cytokines primarily protect and optimize the functioning of neuronal circuits involved in information processing. The increased local activity of neurons during memory acquisition activates many signaling molecules, and some of them can trigger unwanted processes (including neuroinflammation), but increased levels of anti-inflammatory cytokines prevent this triggering. Each of the anti-inflammatory cytokines plays a specific role in supporting information processing. For example, the role of IL-4 and IL-13 in recruiting T cells to the meninges during training in healthy animals has been most studied. It has also been shown that TGF-β is able to optimize late stage LTP in the hippocampus and support the consolidation of memory traces in behavioral studies. Cytokines have an effect on learning and memory through their influence on neuroplasticity, neurogenesis in the hippocampus and regulation of the neurovascular unit. Experiments have shown such an effect, and the data obtained create the prerequisites for new therapeutic approaches to the correction of cognitive impairments.
Collapse
Affiliation(s)
- Sergey G Levin
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Ekaterina V Pershina
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia.
| | - Nickolay A Bugaev-Makarovskiy
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Irina Yu Chernomorets
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Maxim V Konakov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Vladimir I Arkhipov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| |
Collapse
|
11
|
Porcher L, Bruckmeier S, Burbano SD, Finnell JE, Gorny N, Klett J, Wood SK, Kelly MP. Aging triggers an upregulation of a multitude of cytokines in the male and especially the female rodent hippocampus but more discrete changes in other brain regions. J Neuroinflammation 2021; 18:219. [PMID: 34551810 PMCID: PMC8459490 DOI: 10.1186/s12974-021-02252-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 08/25/2021] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Despite widespread acceptance that neuroinflammation contributes to age-related cognitive decline, studies comparing protein expression of cytokines in the young versus old brains are surprisingly limited in terms of the number of cytokines and brain regions studied. Complicating matters, discrepancies abound-particularly for interleukin 6 (IL-6)-possibly due to differences in sex, species/strain, and/or the brain regions studied. METHODS As such, we clarified how cytokine expression changes with age by using a Bioplex and Western blot to measure multiple cytokines across several brain regions of both sexes, using 2 mouse strains bred in-house as well as rats obtained from NIA. Parametric and nonparametric statistical tests were used as appropriate. RESULTS In the ventral hippocampus of C57BL/6J mice, we found age-related increases in IL-1α, IL-1β, IL-2, IL-3, IL-4, IL-6, IL-9, IL-10, IL-12p40, IL-12p70, IL-13, IL-17, eotaxin, G-CSF, interfeuron δ, KC, MIP-1a, MIP-1b, rantes, and TNFα that are generally more pronounced in females, but no age-related change in IL-5, MCP-1, or GM-CSF. We also find aging is uniquely associated with the emergence of a module (a.k.a. network) of 11 strongly intercorrelated cytokines, as well as an age-related shift from glycosylated to unglycosylated isoforms of IL-10 and IL-1β in the ventral hippocampus. Interestingly, age-related increases in extra-hippocampal cytokine expression are more discreet, with the prefrontal cortex, striatum, and cerebellum of male and female C57BL/6J mice demonstrating robust age-related increase in IL-6 expression but not IL-1β. Importantly, we found this widespread age-related increase in IL-6 also occurs in BALB/cJ mice and Brown Norway rats, demonstrating conservation across species and rearing environments. CONCLUSIONS Thus, age-related increases in cytokines are more pronounced in the hippocampus compared to other brain regions and can be more pronounced in females versus males depending on the brain region, genetic background, and cytokine examined.
Collapse
Affiliation(s)
- Latarsha Porcher
- Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, 6439 Garners Ferry Rd, Columbia, SC, 29209, USA
| | - Sophie Bruckmeier
- Department of Anatomy & Neurobiology, University of Maryland School of Medicine, 20 Penn St, HSFII Rm 216, Baltimore, MD, 21201, USA
| | - Steven D Burbano
- Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, 6439 Garners Ferry Rd, Columbia, SC, 29209, USA
| | - Julie E Finnell
- Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, 6439 Garners Ferry Rd, Columbia, SC, 29209, USA
| | - Nicole Gorny
- Department of Anatomy & Neurobiology, University of Maryland School of Medicine, 20 Penn St, HSFII Rm 216, Baltimore, MD, 21201, USA
| | - Jennifer Klett
- Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, 6439 Garners Ferry Rd, Columbia, SC, 29209, USA
| | - Susan K Wood
- Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, 6439 Garners Ferry Rd, Columbia, SC, 29209, USA
| | - Michy P Kelly
- Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, 6439 Garners Ferry Rd, Columbia, SC, 29209, USA. .,Department of Anatomy & Neurobiology, University of Maryland School of Medicine, 20 Penn St, HSFII Rm 216, Baltimore, MD, 21201, USA. .,Center for Research on Aging, University of Maryland School of Medicine, 20 Penn St, HSFII Rm 216, Baltimore, MD, 21201, USA.
| |
Collapse
|
12
|
Hayley S, Hakim AM, Albert PR. Depression, dementia and immune dysregulation. Brain 2021; 144:746-760. [PMID: 33279966 DOI: 10.1093/brain/awaa405] [Citation(s) in RCA: 83] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/26/2020] [Accepted: 09/20/2020] [Indexed: 12/17/2022] Open
Abstract
Major depression is a prevalent illness that increases the risk of several neurological conditions. These include stroke, cardiovascular disease, and dementia including Alzheimer's disease. In this review we ask whether certain types of depression and associated loneliness may be a harbinger of cognitive decline and possibly even dementia. We propose that chronic stress and inflammation combine to compromise vascular and brain function. The resulting increases in proinflammatory cytokines and microglial activation drive brain pathology leading to depression and mild cognitive impairment, which may progress to dementia. We present evidence that by treating the inflammatory changes, depression can be reversed in many cases. Importantly, there is evidence that anti-inflammatory and antidepressant treatments may reduce or prevent dementia in people with depression. Thus, we propose a model in which chronic stress and inflammation combine to increase brain permeability and cytokine production. This leads to microglial activation, white matter damage, neuronal and glial cell loss. This is first manifest as depression and mild cognitive impairment, but can eventually evolve into dementia. Further research may identify clinical subgroups with inflammatory depression at risk for dementia. It would then be possible to address in clinical trials whether effective treatment of the depression can delay the onset of dementia.
Collapse
Affiliation(s)
- Shawn Hayley
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Antoine M Hakim
- Ottawa Hospital Research Institute (Neuroscience), uOttawa Brain and Mind Research Institute, Ottawa, ON, Canada
| | - Paul R Albert
- Ottawa Hospital Research Institute (Neuroscience), uOttawa Brain and Mind Research Institute, Ottawa, ON, Canada
| |
Collapse
|
13
|
Cotrone TS, Hocog CB, Ramsey JT, Sanchez MA, Sullivan HM, Scrimgeour AG. Phenotypic characterization of frontal cortex microglia in a rat model of post-traumatic stress disorder. Brain Behav 2021; 11:e02011. [PMID: 33434400 PMCID: PMC7994680 DOI: 10.1002/brb3.2011] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 01/11/2023] Open
Abstract
INTRODUCTION Post-traumatic stress disorder (PTSD) is an anxiety disorder induced by psychologically traumatic events. Using a rat model, this study aimed to determine whether psychological trauma alters relative expression between pro-inflammatory and anti-inflammatory markers in microglia. To meet this goal, expression of genes encoding i-NOS, arginase, TNF-α, interleukin-10, CD74, and Mannose Receptor C was analyzed on multiple days following trauma exposure. METHODS Single-prolonged stress (SPS) was used to model PTSD in male Sprague-Dawley rats. Twenty-four rats (12 Controls and 12 SPS-exposed) were sacrificed on Days 1, 3, and 7 post-SPS. Twenty-four (12 Controls and 12 SPS-exposed) additional rats were exposed to classical fear conditioning on Day 7, and fear extinction on Days 8, 9, 10, 15, 16, and 17. Freezing behavior was measured to assess fear resolution. Microglial isolates were collected from the frontal cortex, and RNA was extracted. Changes in relative expression of target genes were quantified via RT-PCR. RESULTS SPS rats showed significant decreases in IL-10 and TNF-α expression and increases in the i-NOS:Arginase and TNF-α:IL-10 ratios compared to Controls on Day 1, but not on Day 3 or Day 7 for any of the dependent variables. Day 17 SPS rats showed a significant decrease in IL-10 expression and an increase in the TNF-α:IL-10 ratio, further characterized by a significant inverse relationship between IL-10 expression and fear persistence. CONCLUSION Psychological trauma impacts the immunological phenotype of microglia of the frontal cortex. Consequently, future studies should further evaluate the mechanistic role of microglia in PTSD pathology.
Collapse
Affiliation(s)
- Thomas S Cotrone
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Charina B Hocog
- Veterinary Support and Oversight Branch, U.S. Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Joseph T Ramsey
- Veterinary Support and Oversight Branch, U.S. Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Marcus A Sanchez
- Veterinary Support and Oversight Branch, U.S. Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Heather M Sullivan
- Veterinary Support and Oversight Branch, U.S. Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Angus G Scrimgeour
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA, USA
| |
Collapse
|
14
|
Lenz M, Eichler A, Kruse P, Strehl A, Rodriguez-Rozada S, Goren I, Yogev N, Frank S, Waisman A, Deller T, Jung S, Maggio N, Vlachos A. Interleukin 10 Restores Lipopolysaccharide-Induced Alterations in Synaptic Plasticity Probed by Repetitive Magnetic Stimulation. Front Immunol 2020; 11:614509. [PMID: 33391287 PMCID: PMC7772211 DOI: 10.3389/fimmu.2020.614509] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/16/2020] [Indexed: 12/26/2022] Open
Abstract
Systemic inflammation is associated with alterations in complex brain functions such as learning and memory. However, diagnostic approaches to functionally assess and quantify inflammation-associated alterations in synaptic plasticity are not well-established. In previous work, we demonstrated that bacterial lipopolysaccharide (LPS)-induced systemic inflammation alters the ability of hippocampal neurons to express synaptic plasticity, i.e., the long-term potentiation (LTP) of excitatory neurotransmission. Here, we tested whether synaptic plasticity induced by repetitive magnetic stimulation (rMS), a non-invasive brain stimulation technique used in clinical practice, is affected by LPS-induced inflammation. Specifically, we explored brain tissue cultures to learn more about the direct effects of LPS on neural tissue, and we tested for the plasticity-restoring effects of the anti-inflammatory cytokine interleukin 10 (IL10). As shown previously, 10 Hz repetitive magnetic stimulation (rMS) of organotypic entorhino-hippocampal tissue cultures induced a robust increase in excitatory neurotransmission onto CA1 pyramidal neurons. Furthermore, LPS-treated tissue cultures did not express rMS-induced synaptic plasticity. Live-cell microscopy in tissue cultures prepared from a novel transgenic reporter mouse line [C57BL/6-Tg(TNFa-eGFP)] confirms that ex vivo LPS administration triggers microglial tumor necrosis factor alpha (TNFα) expression, which is ameliorated in the presence of IL10. Consistent with this observation, IL10 hampers the LPS-induced increase in TNFα, IL6, IL1β, and IFNγ and restores the ability of neurons to express rMS-induced synaptic plasticity in the presence of LPS. These findings establish organotypic tissue cultures as a suitable model for studying inflammation-induced alterations in synaptic plasticity, thus providing a biological basis for the diagnostic use of transcranial magnetic stimulation in the context of brain inflammation.
Collapse
Affiliation(s)
- Maximilian Lenz
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Amelie Eichler
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Pia Kruse
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Andreas Strehl
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University Frankfurt, Frankfurt, Germany
| | - Silvia Rodriguez-Rozada
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University Frankfurt, Frankfurt, Germany
| | - Itamar Goren
- Pharmazentrum Frankfurt/ZAFES, Goethe-University Frankfurt, Frankfurt, Germany
| | - Nir Yogev
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Department of Dermatology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Stefan Frank
- Pharmazentrum Frankfurt/ZAFES, Goethe-University Frankfurt, Frankfurt, Germany
| | - Ari Waisman
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Thomas Deller
- Institute of Clinical Neuroanatomy, Neuroscience Center, Goethe-University Frankfurt, Frankfurt, Germany
| | - Steffen Jung
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
| | - Nicola Maggio
- Department of Neurology and Sagol Center for Neurosciences, Talpiot Medical Leadership Program, The Chaim Sheba Medical Center, Tel HaShomer, Israel
- Sackler Faculty of Medicine and Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel
| | - Andreas Vlachos
- Department of Neuroanatomy, Institute of Anatomy and Cell Biology, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Center Brain Links Brain Tools, University of Freiburg, Freiburg, Germany
- Center for Basics in NeuroModulation (NeuroModulBasics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| |
Collapse
|
15
|
Different Activation of IL-10 in the Hippocampus and Prefrontal Cortex During Neurodegeneration Caused by Trimethyltin Chloride. J Mol Neurosci 2020; 71:613-617. [PMID: 32803646 DOI: 10.1007/s12031-020-01682-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 08/10/2020] [Indexed: 12/24/2022]
Abstract
Anti-inflammatory cytokine interleukin-10 (IL-10) plays a crucial role in controlling the resolution of inflammation. In this study, we aimed to assess gene expression and the level of IL-10 in the hippocampus and prefrontal cortex of rats, after a single injection of neurotoxicant trimethyltin chloride (TMT). It was shown that 4 weeks after the treatment with TMT, the level of IL-10 in the prefrontal cortex, but not in the hippocampus of TMT-treated rats, was increased. However, expression level of IL-10 mRNA was upregulated both in the hippocampus and in the prefrontal cortex 3 weeks after the injection. Concomitantly, within the same post-treatment period, the expression level of the cyclooxygenase-2 was upregulated in both brain structures, indicating the induction of neuroinflammation. Considering that TMT leads to the death of neurons mainly in the hippocampus, we assume that in contrast to the prefrontal cortex, the level of anti-inflammatory cytokine IL-10 in the hippocampus is not sufficiently increased to prevent the damaging effect of the neurotoxicant. Therefore, an exogenous increase in the level of IL-10 may be useful for the survival of neurons in conditions of neurotoxic damage to the hippocampus.
Collapse
|
16
|
TGF-β/Smad3 Signalling Modulates GABA Neurotransmission: Implications in Parkinson's Disease. Int J Mol Sci 2020; 21:ijms21020590. [PMID: 31963327 PMCID: PMC7013528 DOI: 10.3390/ijms21020590] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 01/13/2020] [Accepted: 01/14/2020] [Indexed: 12/12/2022] Open
Abstract
γ-Aminobutiryc acid (GABA) is found extensively in different brain nuclei, including parts involved in Parkinson’s disease (PD), such as the basal ganglia and hippocampus. In PD and in different models of the disorder, an increase in GABA neurotransmission is observed and may promote bradykinesia or L-Dopa-induced side-effects. In addition, proteins involved in GABAA receptor (GABAAR) trafficking, such as GABARAP, Trak1 or PAELR, may participate in the aetiology of the disease. TGF-β/Smad3 signalling has been associated with several pathological features of PD, such as dopaminergic neurodegeneration; reduction of dopaminergic axons and dendrites; and α-synuclein aggregation. Moreover, TGF-β/Smad3 intracellular signalling was recently shown to modulate GABA neurotransmission in the context of parkinsonism and cognitive alterations. This review provides a summary of GABA neurotransmission and TGF-β signalling; their implications in PD; and the regulation of GABA neurotransmission by TGF-β/Smad3. There appear to be new possibilities to develop therapeutic approaches for the treatment of PD using GABA modulators.
Collapse
|