scholarly journals Multiple Roles of Peripheral Immune System in Modulating Ischemia/Hypoxia-Induced Neuroinflammation

2021 ◽  
Vol 8 ◽  
Author(s):  
Liang Guo ◽  
Lingling Zhu

Given combined efforts of neuroscience and immunology, increasing evidence has revealed the critical roles of the immune system in regulating homeostasis and disorders of the central nervous system (CNS). Microglia have long been considered as the only immune cell type in parenchyma, while at the interface between CNS and the peripheral (meninges, choroid plexus, and perivascular space), embryonically originated border-associated macrophages (BAMs) and multiple surveilling leukocytes capable of migrating into and out of the brain have been identified to function in the healthy brain. Hypoxia-induced neuroinflammation is the key pathological procedure that can be detected in healthy people at high altitude or in various neurodegenerative diseases, during which a very thin line between a beneficial response of the peripheral immune system in maintaining brain homeostasis and a pathological role in exacerbating neuroinflammation has been revealed. Here, we are going to focus on the role of the peripheral immune system and its crosstalk with CNS in the healthy brain and especially in hypobaric or ischemic hypoxia-associated neuroinflammation.

2021 ◽  
Vol 10 (11) ◽  
pp. 2358
Author(s):  
Maria Grazia Giovannini ◽  
Daniele Lana ◽  
Chiara Traini ◽  
Maria Giuliana Vannucchi

The microbiota–gut system can be thought of as a single unit that interacts with the brain via the “two-way” microbiota–gut–brain axis. Through this axis, a constant interplay mediated by the several products originating from the microbiota guarantees the physiological development and shaping of the gut and the brain. In the present review will be described the modalities through which the microbiota and gut control each other, and the main microbiota products conditioning both local and brain homeostasis. Much evidence has accumulated over the past decade in favor of a significant association between dysbiosis, neuroinflammation and neurodegeneration. Presently, the pathogenetic mechanisms triggered by molecules produced by the altered microbiota, also responsible for the onset and evolution of Alzheimer disease, will be described. Our attention will be focused on the role of astrocytes and microglia. Numerous studies have progressively demonstrated how these glial cells are important to ensure an adequate environment for neuronal activity in healthy conditions. Furthermore, it is becoming evident how both cell types can mediate the onset of neuroinflammation and lead to neurodegeneration when subjected to pathological stimuli. Based on this information, the role of the major microbiota products in shifting the activation profiles of astrocytes and microglia from a healthy to a diseased state will be discussed, focusing on Alzheimer disease pathogenesis.


Author(s):  
Katarzyna Chamera ◽  
Magdalena Szuster-Głuszczak ◽  
Agnieszka Basta-Kaim

AbstractSchizophrenia has a complex and heterogeneous molecular and clinical picture. Over the years of research on this disease, many factors have been suggested to contribute to its pathogenesis. Recently, the inflammatory processes have gained particular interest in the context of schizophrenia due to the increasing evidence from epidemiological, clinical and experimental studies. Within the immunological component, special attention has been brought to chemokines and their receptors. Among them, CX3C chemokine receptor 1 (CX3CR1), which belongs to the family of seven-transmembrane G protein-coupled receptors, and its cognate ligand (CX3CL1) constitute a unique system in the central nervous system. In the view of regulation of the brain homeostasis through immune response, as well as control of microglia reactivity, the CX3CL1–CX3CR1 system may represent an attractive target for further research and schizophrenia treatment. In the review, we described the general characteristics of the CX3CL1–CX3CR1 axis and the involvement of this signaling pathway in the physiological processes whose disruptions are reported to participate in mechanisms underlying schizophrenia. Furthermore, based on the available clinical and experimental data, we presented a guide to understanding the implication of the CX3CL1–CX3CR1 dysfunctions in the course of schizophrenia.


2020 ◽  
Vol 11 ◽  
Author(s):  
Quirijn P. Verhoog ◽  
Linda Holtman ◽  
Eleonora Aronica ◽  
Erwin A. van Vliet

Astrocytes are key homeostatic regulators in the central nervous system and play important roles in physiology. After brain damage caused by e.g., status epilepticus, traumatic brain injury, or stroke, astrocytes may adopt a reactive phenotype. This process of reactive astrogliosis is important to restore brain homeostasis. However, persistent reactive astrogliosis can be detrimental for the brain and contributes to the development of epilepsy. In this review, we will focus on physiological functions of astrocytes in the normal brain as well as pathophysiological functions in the epileptogenic brain, with a focus on acquired epilepsy. We will discuss the role of astrocyte-related processes in epileptogenesis, including reactive astrogliosis, disturbances in energy supply and metabolism, gliotransmission, and extracellular ion concentrations, as well as blood-brain barrier dysfunction and dysregulation of blood flow. Since dysfunction of astrocytes can contribute to epilepsy, we will also discuss their role as potential targets for new therapeutic strategies.


2003 ◽  
Vol 5 (2) ◽  
pp. 139-153

Recent research has overcome the old paradigms of the brain as an immunologically privileged organ, and of the exclusive role of neurotransmitters and neuropeptides as signal transducers in the central nervous system. Growing evidence suggests that the signal proteins of the immune system - the cytokines - are also involved in modulation of behavior and induction of psychiatric symptoms. This article gives an overview on the nature of cytokines and the proposed mechanisms of immune-to-brain interaction. The role of cytokines in psychiatric symptoms, syndromes, and disorders like sickness behavior, major depression, and schizophrenia are discussed together with recent immunogenetic findings.


Author(s):  
Azahara María García-Serna ◽  
Elena Martín-Orozco ◽  
Trinidad Hernández-Caselles ◽  
Eva Morales

It is suggested that programming of the immune system starts before birth and is shaped by environmental influences acting during critical windows of susceptibility for human development. Prenatal and perinatal exposure to physiological, biological, physical, or chemical factors can trigger permanent, irreversible changes to the developing immune system, which may be reflected in cord blood of neonates. The aim of this narrative review is to summarize the evidence on the role of the prenatal and perinatal environment, including season of birth, mode of delivery, exposure to common allergens, a farming environment, pet ownership, and exposure to tobacco smoking and pollutants, in shaping the immune cell populations and cytokines at birth in humans. We also discuss how reported disruptions in the immune system at birth might contribute to the development of asthma and related allergic manifestations later in life.


2021 ◽  
Vol 22 (11) ◽  
pp. 6141
Author(s):  
Teodora Larisa Timis ◽  
Ioan Alexandru Florian ◽  
Sergiu Susman ◽  
Ioan Stefan Florian

Aneurysms and vascular malformations of the brain represent an important source of intracranial hemorrhage and subsequent mortality and morbidity. We are only beginning to discern the involvement of microglia, the resident immune cell of the central nervous system, in these pathologies and their outcomes. Recent evidence suggests that activated proinflammatory microglia are implicated in the expansion of brain injury following subarachnoid hemorrhage (SAH) in both the acute and chronic phases, being also a main actor in vasospasm, considerably the most severe complication of SAH. On the other hand, anti-inflammatory microglia may be involved in the resolution of cerebral injury and hemorrhage. These immune cells have also been observed in high numbers in brain arteriovenous malformations (bAVM) and cerebral cavernomas (CCM), although their roles in these lesions are currently incompletely ascertained. The following review aims to shed a light on the most significant findings related to microglia and their roles in intracranial aneurysms and vascular malformations, as well as possibly establish the course for future research.


2021 ◽  
Vol 11 (3) ◽  
pp. 334
Author(s):  
Giulia Bivona ◽  
Bruna Lo Sasso ◽  
Caterina Maria Gambino ◽  
Rosaria Vincenza Giglio ◽  
Concetta Scazzone ◽  
...  

Vitamin D and cognition is a popular association, which led to a remarkable body of literature data in the past 50 years. The brain can synthesize, catabolize, and receive Vitamin D, which has been proved to regulate many cellular processes in neurons and microglia. Vitamin D helps synaptic plasticity and neurotransmission in dopaminergic neural circuits and exerts anti-inflammatory and neuroprotective activities within the brain by reducing the synthesis of pro-inflammatory cytokines and the oxidative stress load. Further, Vitamin D action in the brain has been related to the clearance of amyloid plaques, which represent a feature of Alzheimer Disease (AD), by the immune cell. Based on these considerations, many studies have investigated the role of circulating Vitamin D levels in patients affected by a cognitive decline to assess Vitamin D’s eventual role as a biomarker or a risk factor in AD. An association between low Vitamin D levels and the onset and progression of AD has been reported, and some interventional studies to evaluate the role of Vitamin D in preventing AD onset have been performed. However, many pitfalls affected the studies available, including substantial discrepancies in the methods used and the lack of standardized data. Despite many studies, it remains unclear whether Vitamin D can have a role in cognitive decline and AD. This narrative review aims to answer two key questions: whether Vitamin D can be used as a reliable tool for diagnosing, predicting prognosis and response to treatment in AD patients, and whether it is a modifiable risk factor for preventing AD onset.


2017 ◽  
Vol 23 (6) ◽  
pp. 587-604 ◽  
Author(s):  
Julien Gibon ◽  
Philip A. Barker

Neurotrophins have been intensively studied and have multiple roles in the brain. Neurotrophins are first synthetized as proneurotrophins and then cleaved intracellularly and extracellularly. Increasing evidences demonstrate that proneurotrophins and mature neurotrophins exerts opposing role in the central nervous system. In the present review, we explore the role of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3), and neurotrophin 4 (NT4) and their respective proform in cellular processes related to learning and memory. We focused on their roles in synaptic activity and plasticity in the brain with an emphasis on long-term potentiation, long-term depression, and basal synaptic transmission in the hippocampus and the temporal lobe area. We also discuss new findings on the role of the Val66Met polymorphism on the BDNF propeptide on synaptic activity.


2020 ◽  
Vol 11 (3) ◽  
pp. 3807-3812
Author(s):  
Aziez Chettoum ◽  
Kamilia Guedri ◽  
Zouhir Djerrou ◽  
Rachid Mosbah ◽  
Latifa Khattabi ◽  
...  

Psychoneuroimmunology or the study of the relationships between the brain and the immune system is an area of research that has experienced significant development over the decade. Stress does not appear without consequences on the state of health, the role of fears, emotions and significant constraints in the appearance of organic and mental diseases. In this research, we studied the effect of stress and anxiety during exams at the end of the academic year (2018/2019) on the distribution of leukocyte subpopulations and the immune system, questionnaires has been completed by student volunteers, to estimate the anxio-depressive comorbidities through the (HADS) test during and outside exams, and in the same time we asked them for a blood sample the next morning day to carry out some biological assays (CBC). We also found that stress during exams caused a change in the distribution of different types of white blood cells, a total decrease in white blood cell counts with neutropenia and lymphopenia were found in students during exams compared to controls, and an increase in monocyte and other types of polymorphonuclear levels in students during exams compared to controls. Other tests measuring the effects of stress on specific functions of the immune system can be used.


Sign in / Sign up

Export Citation Format

Share Document