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Farmen K, Tofiño-Vian M, Wellfelt K, Olson L, Iovino F. Spatio-temporal brain invasion pattern of Streptococcus pneumoniae and dynamic changes in the cellular environment in bacteremia-derived meningitis. Neurobiol Dis 2024; 195:106484. [PMID: 38583642 DOI: 10.1016/j.nbd.2024.106484] [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: 03/18/2024] [Accepted: 03/22/2024] [Indexed: 04/09/2024] Open
Abstract
Streptococcus pneumoniae (the pneumococcus) is the major cause of bacterial meningitis globally, and pneumococcal meningitis is associated with increased risk of long-term neurological sequelae. These include several sensorimotor functions that are controlled by specific brain regions which, during bacterial meningitis, are damaged by a neuroinflammatory response and the deleterious action of bacterial toxins in the brain. However, little is known about the invasion pattern of the pneumococcus into the brain. Using a bacteremia-derived meningitis mouse model, we combined 3D whole brain imaging with brain microdissection to show that all brain regions were equally affected during disease progression, with the presence of pneumococci closely associated to the microvasculature. In the hippocampus, the invasion provoked microglial activation, while the neurogenic niche showed increased proliferation and migration of neuroblasts. Our results indicate that, even before the outbreak of symptoms, the bacterial load throughout the brain is high and causes neuroinflammation and cell death, a pathological scenario which ultimately leads to a failing regeneration of new neurons.
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Affiliation(s)
- Kristine Farmen
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | - Katrin Wellfelt
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Lars Olson
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Federico Iovino
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
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2
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Yan W, Mengke W, Zhiqiang S, Jiaao G, Fulin G. Clinical features, cerebrospinal fluid changes, and prognosis in Chinese patients with autoimmune encephalitis. Acta Neurol Belg 2024:10.1007/s13760-024-02537-6. [PMID: 38635129 DOI: 10.1007/s13760-024-02537-6] [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: 12/06/2023] [Accepted: 03/13/2024] [Indexed: 04/19/2024]
Abstract
INTRODUCTION Autoimmune encephalitis (AE) is a rare, treatable disease of the central nervous system (CNS) caused by an antibody-related immune response. This study is to investigate the correlation of clinical features, cerebrospinal fluid (CSF) characteristics, and prognosis in patients with AE. METHODS A total of 71 patients diagnosed with antibody-positive AE were retrospectively analyzed. The patients were divided into three groups: anti-NMDAR group, anti-LGI1 group, and other types. Clinical data were collected to analyze clinical features and CSF results, and prognosis was determined by modified Rankin Scale (mRS). RESULTS There was statistical difference in the incidences of decreased consciousness level (P < 0.001), memory loss (P = 0.017), speech disorders (P = 0.035), and dyskinesia (P = 0.001) in different antibodies groups. Younger age (P = 0.018), elevated CSF chloride content (P = 0.006), and white blood cells > 50/mm3 (P = 0.026) were highly correlated with ICU admission. Anti-LGI1 encephalitis had a relatively small risk for ICU admission (P = 0.034), and a lower risk of poor functional recovery (P = 0.048) and recurrence (P = 0.041). Patients with first-line treatment failure (P = 0.021) had an increased risk of poor functional recovery. Delayed treatment (P = 0.011) would increase the risk of recurrence. CONCLUSION There are differences in age, gender, clinical characteristics, and CSF results in different subtypes of AE. First-line therapy failure would have poor functional recovery, and delayed therapy would increase the risk of relapse. Chloride ion content and white blood cell count in cerebrospinal fluid are positively correlated with the patient's exacerbation and admission to ICU. These indicators have certain clinical value for the prognosis of AE patients.
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Affiliation(s)
- Wu Yan
- First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
- Xinqiao Hospital and Second Affiliated Hospital of Army Medical University, Chongqing, China
| | - Wang Mengke
- First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Su Zhiqiang
- First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Gu Jiaao
- First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China.
| | - Guan Fulin
- First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China.
- Dushu Lake Hospital Affiliated to Soochow University, Soochow, Jiangsu, China.
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3
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Koning R, van Roon MA, Brouwer MC, van de Beek D. Adjunctive treatments for pneumococcal meningitis: a systematic review of experimental animal models. Brain Commun 2024; 6:fcae131. [PMID: 38707710 PMCID: PMC11069119 DOI: 10.1093/braincomms/fcae131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/22/2023] [Accepted: 04/10/2024] [Indexed: 05/07/2024] Open
Abstract
New treatments are needed to improve the prognosis of pneumococcal meningitis. We performed a systematic review on adjunctive treatments in animal models of pneumococcal meningitis in order to identify treatments with the most potential to progress to clinical trials. Studies testing therapy adjunctive to antibiotics in animal models of pneumococcal meningitis were included. A literature search was performed using Medline, Embase and Scopus for studies published from 1990 up to 17 February 2023. Two investigators screened studies for inclusion and independently extracted data. Treatment effect was assessed on the clinical parameters disease severity, hearing loss and cognitive impairment and the biological parameters inflammation, brain injury and bacterial load. Adjunctive treatments were evaluated by their effect on these outcomes and the quality, number and size of studies that investigated the treatments. Risk of bias was assessed with the SYRCLE risk of bias tool. A total of 58 of 2462 identified studies were included, which used 2703 experimental animals. Disease modelling was performed in rats (29 studies), rabbits (13 studies), mice (12 studies), gerbils (3 studies) or both rats and mice (1 study). Meningitis was induced by injection of Streptococcus pneumoniae into the subarachnoid space. Randomization of experimental groups was performed in 37 of 58 studies (64%) and 12 studies (12%) were investigator-blinded. Overall, 54 treatment regimens using 46 adjunctive drugs were evaluated: most commonly dexamethasone (16 studies), daptomycin (5 studies), complement component 5 (C5; 3 studies) antibody and Mn(III)tetrakis(4-benzoicacid)porphyrin chloride (MnTBAP; 3 studies). The most frequently evaluated outcome parameters were inflammation [32 studies (55%)] and brain injury [32 studies (55%)], followed by disease severity [30 studies (52%)], hearing loss [24 studies (41%)], bacterial load [18 studies (31%)] and cognitive impairment [9 studies (16%)]. Adjunctive therapy that improved clinical outcomes in multiple studies was dexamethasone (6 studies), C5 antibodies (3 studies) and daptomycin (3 studies). HMGB1 inhibitors, matrix metalloproteinase inhibitors, neurotrophins, antioxidants and paquinimod also improved clinical parameters but only in single or small studies. Evaluating the treatment effect of adjunctive therapy was complicated by study heterogeneity regarding the animal models used and outcomes reported. In conclusion, 24 of 54 treatment regimens (44%) tested improved clinically relevant outcomes in experimental pneumococcal meningitis but few were tested in multiple well-designed studies. The most promising new adjunctive treatments are with C5 antibodies or daptomycin, suggesting that these drugs could be tested in clinical trials.
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Affiliation(s)
- Rutger Koning
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, 1100DD Amsterdam, The Netherlands
| | - Marian A van Roon
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, 1100DD Amsterdam, The Netherlands
| | - Matthijs C Brouwer
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, 1100DD Amsterdam, The Netherlands
| | - Diederik van de Beek
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, 1100DD Amsterdam, The Netherlands
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4
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Kumar VS. Parainfectious cerebral vasculopathy complicating bacterial meningitis: Acute-short lived vasospasm followed by delayed-long lasting vasculitis. Brain Circ 2023; 9:135-147. [PMID: 38020954 PMCID: PMC10679625 DOI: 10.4103/bc.bc_95_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 01/29/2023] [Accepted: 02/14/2023] [Indexed: 12/01/2023] Open
Abstract
Bacterial meningitis is a serious, life-threatening infection of the meninges. Several radiological studies highlight prominent structural alterations occurring in the cerebral vasculature, leading to significant cerebrovascular consequences during bacterial meningitis. Beginning with reflexive arterial vasospasm , cerebrovascular disease during bacterial meningitis proceeds through a orderly sequence of arterial vasculitis with inflammatory cell infiltration, medial smooth muscle migration and proliferation, medial necrosis, adventitial fibrosis and eventual intimal stenosis. As such, this review focuses on changes occurring within cerebral arteries during disease progression, highlighting the various structural modifications occurring in the arterial vessels that contribute to disturbances in cerebral hemodynamics and, ultimately, cerebrovascular consequences during bacterial meningitis.
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Affiliation(s)
- Vivig Shantha Kumar
- Department of Internal Medicine, California Institute of Behavioral Neurosciences and Psychology, Fairfield, USA
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5
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Maas SL, Donners MMPC, van der Vorst EPC. ADAM10 and ADAM17, Major Regulators of Chronic Kidney Disease Induced Atherosclerosis? Int J Mol Sci 2023; 24:ijms24087309. [PMID: 37108478 PMCID: PMC10139114 DOI: 10.3390/ijms24087309] [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: 03/15/2023] [Revised: 04/06/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Chronic kidney disease (CKD) is a major health problem, affecting millions of people worldwide, in particular hypertensive and diabetic patients. CKD patients suffer from significantly increased cardiovascular disease (CVD) morbidity and mortality, mainly due to accelerated atherosclerosis development. Indeed, CKD not only affects the kidneys, in which injury and maladaptive repair processes lead to local inflammation and fibrosis, but also causes systemic inflammation and altered mineral bone metabolism leading to vascular dysfunction, calcification, and thus, accelerated atherosclerosis. Although CKD and CVD individually have been extensively studied, relatively little research has studied the link between both diseases. This narrative review focuses on the role of a disintegrin and metalloproteases (ADAM) 10 and ADAM17 in CKD and CVD and will for the first time shed light on their role in CKD-induced CVD. By cleaving cell surface molecules, these enzymes regulate not only cellular sensitivity to their micro-environment (in case of receptor cleavage), but also release soluble ectodomains that can exert agonistic or antagonistic functions, both locally and systemically. Although the cell-specific roles of ADAM10 and ADAM17 in CVD, and to a lesser extent in CKD, have been explored, their impact on CKD-induced CVD is likely, yet remains to be elucidated.
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Affiliation(s)
- Sanne L Maas
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
| | - Marjo M P C Donners
- Department of Pathology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University Medical Centre, 6229 ER Maastricht, The Netherlands
| | - Emiel P C van der Vorst
- Institute for Molecular Cardiovascular Research (IMCAR), RWTH Aachen University, 52074 Aachen, Germany
- Aachen-Maastricht Institute for CardioRenal Disease (AMICARE), RWTH Aachen University, 52074 Aachen, Germany
- Interdisciplinary Center for Clinical Research (IZKF), RWTH Aachen University, 52074 Aachen, Germany
- Institute for Cardiovascular Prevention (IPEK), Ludwig-Maximilians-University Munich (LMU), 80336 Munich, Germany
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Le ND, Steinfort M, Grandgirard D, Maleska A, Leppert D, Kuhle J, Leib SL. The CCR5 antagonist maraviroc exerts limited neuroprotection without improving neurofunctional outcome in experimental pneumococcal meningitis. Sci Rep 2022; 12:12945. [PMID: 35902720 PMCID: PMC9334283 DOI: 10.1038/s41598-022-17282-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/22/2022] [Indexed: 11/10/2022] Open
Abstract
One-third of pneumococcal meningitis (PM) survivors suffer from neurological sequelae including learning disabilities and hearing loss due to excessive neuroinflammation. There is a lack of efficacious compounds for adjuvant therapy to control this long-term consequence of PM. One hallmark is the recruitment of leukocytes to the brain to combat the bacterial spread. However, this process induces excessive inflammation, causing neuronal injury. Maraviroc (MVC)—a CCR5 antagonist—was demonstrated to inhibit leukocyte recruitment and attenuate neuroinflammation in several inflammatory diseases. Here, we show that in vitro, MVC decreased nitric oxide production in astroglial cells upon pneumococcal stimulation. In vivo, infant Wistar rats were infected with 1 × 104 CFU/ml S. pneumoniae and randomized for treatment with ceftriaxone plus MVC (100 mg/kg) or ceftriaxone monotherapy. During the acute phase, neuroinflammation in the CSF was measured and histopathological analyses were performed to determine neuronal injury. Long-term neurofunctional outcome (learning/memory and hearing capacity) after PM was assessed. MVC treatment reduced hippocampal cell apoptosis but did not affect CSF neuroinflammation and the neurofunctional outcome after PM. We conclude that MVC treatment only exerted limited effect on the pathophysiology of PM and is, therefore, not sufficiently beneficial in this experimental paradigm of PM.
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Affiliation(s)
- Ngoc Dung Le
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Bern, Switzerland
| | - Marel Steinfort
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Aleksandra Maleska
- Multiple Sclerosis Centre, Neurology, Departments of Head, Spine and Neuromedicine, Biomedicine and Clinical Research, University Hospital Basel and University of Basel, Basel, Switzerland.,Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB), University Hospital and University of Basel, Basel, Switzerland
| | - David Leppert
- Multiple Sclerosis Centre, Neurology, Departments of Head, Spine and Neuromedicine, Biomedicine and Clinical Research, University Hospital Basel and University of Basel, Basel, Switzerland.,Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB), University Hospital and University of Basel, Basel, Switzerland
| | - Jens Kuhle
- Multiple Sclerosis Centre, Neurology, Departments of Head, Spine and Neuromedicine, Biomedicine and Clinical Research, University Hospital Basel and University of Basel, Basel, Switzerland.,Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB), University Hospital and University of Basel, Basel, Switzerland
| | - Stephen L Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland.
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7
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Farmen K, Tofiño-Vian M, Iovino F. Neuronal Damage and Neuroinflammation, a Bridge Between Bacterial Meningitis and Neurodegenerative Diseases. Front Cell Neurosci 2021; 15:680858. [PMID: 34149363 PMCID: PMC8209290 DOI: 10.3389/fncel.2021.680858] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 05/03/2021] [Indexed: 12/13/2022] Open
Abstract
Bacterial meningitis is an inflammation of the meninges which covers and protects the brain and the spinal cord. Such inflammation is mostly caused by blood-borne bacteria that cross the blood-brain barrier (BBB) and finally invade the brain parenchyma. Pathogens such as Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae are the main etiological causes of bacterial meningitis. After trafficking across the BBB, bacterial pathogens in the brain interact with neurons, the fundamental units of Central Nervous System, and other types of glial cells. Although the specific molecular mechanism behind the interaction between such pathogens with neurons is still under investigation, it is clear that bacterial interaction with neurons and neuroinflammatory responses within the brain leads to neuronal cell death. Furthermore, clinical studies have shown indications of meningitis-caused dementia; and a variety of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease and Huntington's disease are characterized by the loss of neurons, which, unlike many other eukaryotic cells, once dead or damaged, they are seldom replaced. The aim of this review article is to provide an overview of the knowledge on how bacterial pathogens in the brain damage neurons through direct and indirect interactions, and how the neuronal damage caused by bacterial pathogen can, in the long-term, influence the onset of neurodegenerative disorders.
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Affiliation(s)
| | | | - Federico Iovino
- Department of Neuroscience, Karolinska Institutet Biomedicum, Stockholm, Sweden
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8
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Aljohmani A, Yildiz D. A Disintegrin and Metalloproteinase-Control Elements in Infectious Diseases. Front Cardiovasc Med 2020; 7:608281. [PMID: 33392273 PMCID: PMC7772189 DOI: 10.3389/fcvm.2020.608281] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 11/09/2020] [Indexed: 12/12/2022] Open
Abstract
Despite recent advances in treatment strategies, infectious diseases are still under the leading causes of death worldwide. Although the activation of the inflammatory cascade is one prerequisite of defense, persistent and exuberant immune response, however, may lead to chronicity of inflammation predisposing to a temporal or permanent tissue damage not only of the site of infection but also among different body organs. The initial response to invading pathogens is mediated by the recognition through various pattern-recognition receptors along with cellular engulfment resulting in a coordinated release of soluble effector molecules and cytokines aiming to terminate the external stimuli. Members of the ‘a disintegrin and metalloproteinase’ (ADAM) family have the capability to proteolytically cleave transmembrane molecules close to the plasma membrane, a process called ectodomain shedding. In fact, in infectious diseases dysregulation of numerous ADAM substrates such as junction molecules (e.g., E-cadherin, VE-cadherin, JAM-A), adhesion molecules (e.g., ICAM-1, VCAM-1, L-selectin), and chemokines and cytokines (e.g., CXCL16, TNF-α) has been observed. The alpha-cleavage by ADAM proteases represents a rate limiting step for downstream regulated intramembrane proteolysis (RIPing) of several substrates, which influence cellular differentiation, cell signaling pathways and immune modulation. Both the substrates mentioned above and RIPing crucially contribute to a systematic damage in cardiovascular, endocrine, and/or gastrointestinal systems. This review will summarize the current knowledge of ADAM function and the subsequent RIPing in infectious diseases (e.g., pathogen recognition and clearance) and discuss the potential long-term effect on pathophysiological changes such as cardiovascular diseases.
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Affiliation(s)
- Ahmad Aljohmani
- Institute of Experimental and Clinical Pharmacology and Toxicology, PZMS, ZHMB, Saarland University, Homburg, Germany
| | - Daniela Yildiz
- Institute of Experimental and Clinical Pharmacology and Toxicology, PZMS, ZHMB, Saarland University, Homburg, Germany
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9
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Pan SD, Grandgirard D, Leib SL. Adjuvant Cannabinoid Receptor Type 2 Agonist Modulates the Polarization of Microglia Towards a Non-Inflammatory Phenotype in Experimental Pneumococcal Meningitis. Front Cell Infect Microbiol 2020; 10:588195. [PMID: 33251159 PMCID: PMC7674855 DOI: 10.3389/fcimb.2020.588195] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/14/2020] [Indexed: 12/26/2022] Open
Abstract
Background Microglia initiates and sustains the inflammatory reaction that drives the pathogenesis of pneumococcal meningitis. The expression of the G-protein cannabinoid receptor type 2 (CB2) in the brain is low, but is upregulated in glial cells during infection. Its activation down-regulates pro-inflammatory processes, driving microglia towards an anti-inflammatory phenotype. CB2 agonists are therefore therapeutic candidates in inflammatory conditions like pneumococcal meningitis. We evaluated the effects of JWH-133, a specific CB2 agonist on microglial cells, inflammation, and damage driven by S. pneumoniae in vitro and in experimental pneumococcal meningitis. Materials/methods Primary mixed glial cultures were stimulated with live or heat-inactivated S. pneumoniae, or lipopolysaccharide and treated with JWH-133 or vehicle. Nitric oxide and cytokines levels were measured in the supernatant. In vivo, pneumococcal meningitis was induced by intracisternal injection of live S. pneumoniae in 11 days old Wistar rats. Animals were treated with antibiotics (Ceftriaxone, 100 mg/kg, s.c. bid) and JWH-133 (1 mg/kg, i.p. daily) or vehicle (10% Ethanol in saline, 100 µl/25g body weight) at 18 h after infection. Brains were harvested at 24 and 42 h post infection (hpi) for histological assessment of hippocampal apoptosis and cortical damage and determination of cyto/chemokines in tissue homogenates. Microglia were characterized using Iba-1 immunostaining. Inflammation in brain homogenates was determined using membrane-based antibody arrays. Results In vitro, nitric oxide and cytokines levels were significantly lowered by JWH-133 treatment. In vivo, clinical parameters were not affected by the treatment. JWH-133 significantly lowered microglia activation assessed by quantification of cell process length and endpoints per microglia. Animals treated with JWH-133 demonstrated significantly lower parenchymal levels of chemokines (CINC-1, CINC-2α/β, and MIP-3α), TIMP-1, and IL-6 at 24 hpi, and CINC-1, MIP-1α, and IL-1α at 42 hpi. Quantitative analysis of brain damage did not reveal an effect of JWH-133. Conclusions JWH-133 attenuates microglial activation and downregulates the concentrations of pro-inflammatory mediators in pneumococcal infection in vitro and in vivo. However, we didn't observe a reduction in cortical or hippocampal injury. This data provides evidence that inhibition of microglia by adjuvant CB2 agonists therapy effectively downmodulates neuroinflammation but does not reduce brain damage in experimental pneumococcal meningitis.
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Affiliation(s)
- Steven D Pan
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Stephen L Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
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10
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Le ND, Muri L, Grandgirard D, Kuhle J, Leppert D, Leib SL. Evaluation of neurofilament light chain in the cerebrospinal fluid and blood as a biomarker for neuronal damage in experimental pneumococcal meningitis. J Neuroinflammation 2020; 17:293. [PMID: 33028339 PMCID: PMC7539528 DOI: 10.1186/s12974-020-01966-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022] Open
Abstract
Background Pneumococcal meningitis (PM) remains a global public health concern and affects all age groups. If acquired during infancy or childhood, permanent neurofunctional deficits including cognitive impairment, cerebral palsy, and secondary epilepsy are typical sequelae of neuronal injury. Determination of patients at risk for the development of brain injury and subsequent neurofunctional sequelae could help to identify patients for focused management. Neurofilament light chain (NfL) is an axonal cytoskeletal protein released upon neuronal injury into the cerebrospinal fluid (CSF) and blood. As little is known about the course of neurofilament release in the course of PM, we measured CSF and serum NfL levels longitudinally in experimental PM (ePM). Methods Eleven-day-old infant Wistar rats were infected intracisternally with Streptococcus pneumoniae and treated with ceftriaxone. At 18 and 42 h post-infection (hpi), the blood and CSF were sampled for NfL measurements by a single molecule array technology. Inflammatory cytokines and MMP-9 in CSF were quantified by magnetic bead multiplex assay (Luminex®) and by gel zymography, respectively. Results In ePM, CSF and serum NfL levels started to increase at 18 hpi and were 26- and 3.5-fold increased, respectively, compared to mock-infected animals at 42 hpi (p < 0.0001). CSF and serum NfL correlated at 18 hpi (p < 0.05, r = 0.4716) and 42 hpi (p < 0.0001, r = 0.8179). Both CSF and serum NfL at 42 hpi strongly correlated with CSF levels of IL-1β, TNF-α, and IL-6 and of MMP-9 depending on their individual kinetics. Conclusion Current results demonstrate that during the peak inflammatory phase of ePM, NfL levels in CSF and serum are the highest among CNS disease models studied so far. Given the strong correlation of CSF versus serum NfL, and its CNS-specific signal character, longitudinal measurements to monitor the course of PM could be performed based on blood sample tests, i.e., without the need of repetitive spinal taps. We conclude that NfL in the serum should be evaluated as a biomarker in PM.
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Affiliation(s)
- Ngoc Dung Le
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Bern, Switzerland
| | - Lukas Muri
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001, Bern, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001, Bern, Switzerland
| | - Jens Kuhle
- Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital and University of Basel, Basel, Switzerland
| | - David Leppert
- Neurologic Clinic and Policlinic, Departments of Medicine, Biomedicine and Clinical Research, University Hospital and University of Basel, Basel, Switzerland
| | - Stephen L Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001, Bern, Switzerland.
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Angiostrongylus cantonensis infection induces MMP-9 and causes tight junction protein disruption associated with Purkinje cell degeneration. Parasitol Res 2020; 119:3433-3441. [PMID: 32789733 DOI: 10.1007/s00436-020-06840-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 08/02/2020] [Indexed: 10/23/2022]
Abstract
Angiostrongylus cantonensis causes a human central nervous system (CNS) infection characterized by eosinophilic meningitis or meningoencephalitis. Individuals infected with A. cantonensis exhibit unbalanced walking. The mechanism of extensive neurological impairments of hosts caused by A. cantonensis larvae remains unclear. Tight junction proteins (e.g., claudin-5 and zonula occludens-1) are the most important regulators of paracellular permeability and cellular adhesion. In a previous study, we found that increased matrix metalloproteinase-9 (MMP-9) activity may be associated with blood-CNS barrier disruption and/or the degeneration of Purkinje cells in eosinophilic meningitis caused by A. cantonensis. In the present study, the co-localization of MMP-9 and tight junction proteins on the degeneration of Purkinje cells was measured via confocal laser scanning immunofluorescence microscopy. The statistical evidence indicated that MMP-9 correlated between tight junction protein disruption and Purkinje cell degeneration at 20 days post-infection with A. cantonensis. In conclusion, Purkinje cell degeneration is highly correlated with tight junction protein disruption via the MMP-9 activation pathway.
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12
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Ricci S, Grandgirard D, Masouris I, Braccini T, Pozzi G, Oggioni MR, Koedel U, Leib SL. Combined therapy with ceftriaxone and doxycycline does not improve the outcome of meningococcal meningitis in mice compared to ceftriaxone monotherapy. BMC Infect Dis 2020; 20:505. [PMID: 32660552 PMCID: PMC7359289 DOI: 10.1186/s12879-020-05226-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 07/03/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Meningococcal meningitis (MM) is a life-threatening disease associated with approximately 10% case fatality rates and neurological sequelae in 10-20% of the cases. Recently, we have shown that the matrix metalloproteinase (MMP) inhibitor BB-94 reduced brain injury in a mouse model of MM. The present study aimed to assess whether doxycycline (DOX), a tetracycline that showed a neuroprotective effect as adjuvant therapy in experimental pneumococcal meningitis (PM), would also exert a beneficial effect when given as adjunctive therapy to ceftriaxone (CRO) in experimental MM. METHODS BALB/c mice were infected by the intracisternal route with a group C Neisseria meningitidis strain. Eighteen h post infection (hpi), animals were randomised for treatment with CRO [100 mg/kg subcutaneously (s.c.)], CRO plus DOX (30 mg/kg s.c.) or saline (control s.c.). Antibiotic treatment was repeated 24 and 40 hpi. Mouse survival and clinical signs, bacterial counts in cerebella, brain damage, MMP-9 and cyto/chemokine levels were assessed 48 hpi. RESULTS Analysis of bacterial load in cerebella indicated that CRO and CRO + DOX were equally effective at controlling meningococcal replication. No differences in survival were observed between mice treated with CRO (94.4%) or CRO + DOX (95.5%), (p > 0.05). Treatment with CRO + DOX significantly diminished both the number of cerebral hemorrhages (p = 0.029) and the amount of MMP-9 in the brain (p = 0.046) compared to untreated controls, but not to CRO-treated animals (p > 0.05). Levels of inflammatory markers in the brain of mice that received CRO or CRO + DOX were not significantly different (p > 0.05). Overall, there were no significant differences in the parameters assessed between the groups treated with CRO alone or CRO + DOX. CONCLUSIONS Treatment with CRO + DOX showed similar bactericidal activity to CRO in vivo, suggesting no antagonist effect of DOX on CRO. Combined therapy significantly improved mouse survival and disease severity compared to untreated animals, but addition of DOX to CRO did not offer significant benefits over CRO monotherapy. In contrast to experimental PM, DOX has no adjunctive activity in experimental MM.
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Affiliation(s)
- Susanna Ricci
- Department of Medical Biotechnologies, Laboratory of Molecular Microbiology and Biotechnology (LA.M.M.B.), Ospedale Santa Maria alle Scotte, University of Siena, Siena, Italy. .,ESCMID Study Group for Infectious Diseases of the Brain (ESGIB), Basel, Switzerland.
| | - Denis Grandgirard
- ESCMID Study Group for Infectious Diseases of the Brain (ESGIB), Basel, Switzerland.,Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Ilias Masouris
- Department of Neurology, Ludwig-Maximilians University, Munich, Germany
| | - Tiziana Braccini
- Department of Medical Biotechnologies, Laboratory of Molecular Microbiology and Biotechnology (LA.M.M.B.), Ospedale Santa Maria alle Scotte, University of Siena, Siena, Italy
| | - Gianni Pozzi
- Department of Medical Biotechnologies, Laboratory of Molecular Microbiology and Biotechnology (LA.M.M.B.), Ospedale Santa Maria alle Scotte, University of Siena, Siena, Italy
| | - Marco R Oggioni
- ESCMID Study Group for Infectious Diseases of the Brain (ESGIB), Basel, Switzerland.,Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Uwe Koedel
- ESCMID Study Group for Infectious Diseases of the Brain (ESGIB), Basel, Switzerland.,Department of Neurology, Ludwig-Maximilians University, Munich, Germany
| | - Stephen L Leib
- ESCMID Study Group for Infectious Diseases of the Brain (ESGIB), Basel, Switzerland.,Institute for Infectious Diseases, University of Bern, Bern, Switzerland
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de Queiroz KB, Cavalcante-Silva V, Lopes FL, Rocha GA, D'Almeida V, Coimbra RS. Vitamin B 12 is neuroprotective in experimental pneumococcal meningitis through modulation of hippocampal DNA methylation. J Neuroinflammation 2020; 17:96. [PMID: 32238192 PMCID: PMC7115084 DOI: 10.1186/s12974-020-01763-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 02/27/2020] [Indexed: 02/08/2023] Open
Abstract
Background Bacterial meningitis (BM) causes apoptotic damage to the hippocampus and homocysteine (Hcy) accumulation to neurotoxic levels in the cerebrospinal fluid of children. The Hcy pathway controls bioavailability of methyl, and its homeostasis can be modulated by vitamin B12, a cofactor of the methionine synthase enzyme. Herein, the neuroprotective potential and the underlying mode of action of vitamin B12 adjuvant therapy were assessed in an infant rat model of BM. Methods Eleven-day old rats were intracysternally infected with Streptococcus pneumoniae serotype 3, or saline, treated with B12 or placebo, and, 24 h after infection, their hippocampi were analyzed for apoptosis in the dentate gyrus, sulfur amino acids content, global DNA methylation, transcription, and proximal promoter methylation of candidate genes. Differences between groups were compared using 2-way ANOVA followed by Bonferroni post hoc test. Correlations were tested with Spearman’s test. Results B12 attenuated BM-induced hippocampal apoptosis in a Hcy-dependent manner (r = 0.80, P < 0.05). BM caused global DNA hypomethylation; however, B12 restored this parameter. Accordingly, B12 increased the methylation capacity of hippocampal cells from infected animals, as inferred from the ratio S-adenosylmethionine (SAM):S-adenosylhomocysteine (SAH) in infected animals. BM upregulated selected pro-inflammatory genes, and this effect was counteracted by B12, which also increased methylation of CpGs at the promoter of Ccl3 of infected animals. Conclusion Hcy is likely to play a central role in hippocampal damage in the infant rat model of BM, and B12 shows an anti-inflammatory and neuroprotective action through methyl-dependent epigenetic mechanisms.
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Affiliation(s)
- Karina Barbosa de Queiroz
- Neurogenômica/Imunopatologia, Instituto René Rachou (IRR), Fundação Oswaldo Cruz (FIOCRUZ), Av. Augusto de Lima, 1715, Belo Horizonte, MG, CEP 30190-002, Brazil
| | - Vanessa Cavalcante-Silva
- Departamento de Psicobiologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP-EPM), Rua Botucatu, 740, São Paulo, SP, CEP 04023-062, Brazil
| | - Flávia Lombardi Lopes
- Faculdade de Medicina Veterinária de Araçatuba, Universidade Estadual Paulista (UNESP), R. Clóvis Pestana, 793, Araçatuba, SP, CEP 16050-680, Brazil
| | - Gifone Aguiar Rocha
- Laboratório de Pesquisa em Bacteriologia, Departamento de Propedêutica Complementar, Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG), Av. Prof. Alfredo Balena, 190, Belo Horizonte, MG, CEP 30130-100, Brazil
| | - Vânia D'Almeida
- Departamento de Psicobiologia, Escola Paulista de Medicina, Universidade Federal de São Paulo (UNIFESP-EPM), Rua Botucatu, 740, São Paulo, SP, CEP 04023-062, Brazil
| | - Roney Santos Coimbra
- Neurogenômica/Imunopatologia, Instituto René Rachou (IRR), Fundação Oswaldo Cruz (FIOCRUZ), Av. Augusto de Lima, 1715, Belo Horizonte, MG, CEP 30190-002, Brazil.
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Principi N, Esposito S. Bacterial meningitis: new treatment options to reduce the risk of brain damage. Expert Opin Pharmacother 2019; 21:97-105. [PMID: 31675255 DOI: 10.1080/14656566.2019.1685497] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Introduction: Bacterial meningitis (BM) is a medical emergency and its etiology varies according to the age group and geographic area. Studies have shown that brain damage, sequelae and neuropsychological deficits depend not only on the direct deleterious action of the pathogens, but also on the host defenses themselves.Areas covered: Corticosteroids (CS) were the first drugs used with the intent to limit the exaggerated host response. However, as steroid addition to antibiotics is frequently unsatisfactory, other measures have been suggested. In this study, the most important adjuvant therapies that are potentially useful to limit the neuropsychological damage of BM are discussed.Expert opinion: The pathophysiological mechanisms leading to the development of brain damage are not completely defined. Moreover, the efficacy of adjuvant therapies can vary according to the aetiologic cause of BM, and differences in immune system function of the host can play a relevant role in the expression of inflammation and related problems. It is likely that none of the measures with demonstrated efficacy in animal models can be translated into clinical practice in the next few years, suggesting that to reduce the total burden of BM, the increased use of vaccines seems to be the best solution.
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Affiliation(s)
- Nicola Principi
- Emeritus of Pediatrics, Università degli Studi di Milano, Milan, Italy
| | - Susanna Esposito
- Pietro Barilla Children's Hospital, Department of Medicine and Surgery, University of Parma, Parma, Italy
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15
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Milioli MVM, Burger H, Olivieri R, Michels M, Ávila P, Abatti M, Indalécio A, Ritter C, Dal-Pizzol F. The impact of age on long-term behavioral and neurochemical parameters in an animal model of severe sepsis. Neurosci Lett 2019; 708:134339. [DOI: 10.1016/j.neulet.2019.134339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/12/2019] [Accepted: 06/17/2019] [Indexed: 11/29/2022]
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16
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Muri L, Leppert D, Grandgirard D, Leib SL. MMPs and ADAMs in neurological infectious diseases and multiple sclerosis. Cell Mol Life Sci 2019; 76:3097-3116. [PMID: 31172218 PMCID: PMC7079810 DOI: 10.1007/s00018-019-03174-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 05/23/2019] [Accepted: 05/29/2019] [Indexed: 12/24/2022]
Abstract
Metalloproteinases-such as matrix metalloproteinases (MMPs) and a disintegrin and metalloproteinases (ADAMs)-are involved in various diseases of the nervous system but also contribute to nervous system development, synaptic plasticity and neuroregeneration upon injury. MMPs and ADAMs proteolytically cleave many substrates including extracellular matrix components but also signaling molecules and receptors. During neuroinfectious disease with associated neuroinflammation, MMPs and ADAMs regulate blood-brain barrier breakdown, bacterial invasion, neutrophil infiltration and cytokine signaling. Specific and broad-spectrum inhibitors for MMPs and ADAMs have experimentally been shown to decrease neuroinflammation and brain damage in diseases with excessive neuroinflammation as a common denominator, such as pneumococcal meningitis and multiple sclerosis, thereby improving the disease outcome. Timing of metalloproteinase inhibition appears to be critical to effectively target the cascade of pathophysiological processes leading to brain damage without inhibiting the neuroregenerative effects of metalloproteinases. As the critical role of metalloproteinases in neuronal repair mechanisms and regeneration was only lately recognized, the original idea of chronic MMP inhibition needs to be conceptually revised. Recently accumulated research urges for a second chance of metalloproteinase inhibitors, which-when correctly applied and dosed-harbor the potential to improve the outcome of different neuroinflammatory diseases.
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Affiliation(s)
- Lukas Muri
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Freiestrasse 1, 3012, Bern, Switzerland
| | - David Leppert
- Department of Neurology, University Hospital Basel, Petersgraben 4, 4031, Basel, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001, Bern, Switzerland
| | - Stephen L Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001, Bern, Switzerland.
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17
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Muri L, Le ND, Zemp J, Grandgirard D, Leib SL. Metformin mediates neuroprotection and attenuates hearing loss in experimental pneumococcal meningitis. J Neuroinflammation 2019; 16:156. [PMID: 31351490 PMCID: PMC6660697 DOI: 10.1186/s12974-019-1549-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/18/2019] [Indexed: 12/16/2022] Open
Abstract
Background Pneumococcal meningitis is associated with high risk of neurological sequelae such as cognitive impairment and hearing loss. These sequelae are due to parenchymal brain and inner ear damage primarily induced by the excessive inflammatory reaction in response to bacterial brain invasion. Metformin—a biguanide drug to treat diabetes mellitus type 2—was recently found to suppress neuroinflammation and induce neuroregeneration. This study evaluated the effect of metformin adjunctive to antibiotics on neuroinflammation, brain and inner ear damage, and neurofunctional outcome in experimental pediatric pneumococcal meningitis. Methods Eleven-day-old Wistar rats were infected intracisternally with 5.22 ± 1.27 × 103 CFU Streptococcus pneumoniae and randomized for treatment with metformin (50 mg/kg, i.p., once daily for 3 weeks) plus ceftriaxone (100 mg/kg, i.p., bid, n = 61) or ceftriaxone monotherapy (n = 79). Cortical damage and hippocampal apoptosis were evaluated histomorphometrically 42 h post infection. Cerebrospinal fluid cytokine levels were analyzed during acute infection. Five weeks post infection, auditory brainstem responses were measured to determine hearing thresholds. Spiral ganglion neuron density and abundance of recently proliferated and integrated hippocampal granule neurons were assessed histologically. Additionally, the anti-inflammatory effect of metformin was studied in primary rat astroglial cells in vitro. Results Upon pneumococcal infection, metformin treatment significantly reduced levels of inflammatory cytokines and nitric oxide production in cerebrospinal fluid and in astroglial cell cultures in vitro (p < 0.05). Compared to animals receiving ceftriaxone monotherapy, adjunctive metformin significantly reduced cortical necrosis (p < 0.02) during acute infection and improved median click-induced hearing thresholds (60 dB vs. 100 dB, p < 0.002) 5 weeks after infection. Adjuvant metformin significantly improved pure tone hearing thresholds at all assessed frequencies compared to ceftriaxone monotherapy (p < 0.05) and protected from PM-induced spiral ganglion neuron loss in the inner ear (p < 0.05). Conclusion Adjuvant metformin reduces brain injury during pneumococcal meningitis by decreasing the excessive neuroinflammatory response. Furthermore, it protects spiral ganglion neurons in the inner ear and improves hearing impairments after experimental pneumococcal meningitis. These results identify adjuvant metformin as a promising therapeutic option to improve the outcome after pediatric pneumococcal meningitis. Electronic supplementary material The online version of this article (10.1186/s12974-019-1549-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lukas Muri
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3010, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Mittelstrasse 43, 3012, Bern, Switzerland
| | - Ngoc Dung Le
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3010, Bern, Switzerland.,Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Mittelstrasse 43, 3012, Bern, Switzerland
| | - Jonas Zemp
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3010, Bern, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3010, Bern, Switzerland
| | - Stephen L Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3010, Bern, Switzerland.
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Combining Ceftriaxone with Doxycycline and Daptomycin Reduces Mortality, Neuroinflammation, Brain Damage, and Hearing Loss in Infant Rat Pneumococcal Meningitis. Antimicrob Agents Chemother 2019; 63:AAC.00220-19. [PMID: 31061158 DOI: 10.1128/aac.00220-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/30/2019] [Indexed: 02/07/2023] Open
Abstract
Despite appropriate antibiotic therapy, pneumococcal meningitis (PM) is associated with a case fatality rate of up to 30% in high-income countries. Survivors often suffer from severe lifelong disabilities. An excessive inflammatory reaction drives the pathophysiology, leading to brain damage and neurologic sequelae. We aimed to improve the outcome of experimental PM by simultaneously targeting different pathophysiological mechanisms with combined adjunctive therapies previously shown to be neuroprotective. In vitro, the anti-inflammatory effects of doxycycline and daptomycin were evaluated on primary rat astroglial cells stimulated with Streptococcus pneumoniae Eleven-day-old infant Wistar rats were infected intracisternally with S. pneumoniae and randomized for treatment with ceftriaxone or combination adjuvant therapy consisting of ceftriaxone, daptomycin, and doxycycline. During acute PM, combined-adjuvant therapy with ceftriaxone, daptomycin, and doxycycline increased the survival rate from 64.1% to 85.8% (P < 0.01) and alleviated weight loss compared to ceftriaxone monotherapy (P < 0.01). Levels of inflammatory cytokines were significantly reduced by combined-adjuvant therapy in vitro (P < 0.0001) and in cerebrospinal fluid in vivo (P < 0.05). In infected animals treated with combined adjunctive therapy, cortical damage was significantly reduced (P < 0.05), and animals showed a trend toward better hearing capacity 3 weeks after the infection (P = 0.089), an effect which was significant in mildly infected animals (48 decibels [dB] versus 67.22 dB; P < 0.05). These mildly infected animals showed significantly reduced cochlear fibrous occlusion (P < 0.01). By combining nonbacteriolytic daptomycin and anti-inflammatory doxycycline with ceftriaxone, the previously reported beneficial effects of the drugs were cumulated and identified the triple-antibiotic therapy as a promising therapeutic option for pediatric PM.
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19
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Myeloid-Related Protein 8/14 Participates in the Progression of Experimental Pneumococcal Meningitis by Augmentation of Inflammation. J Mol Neurosci 2019; 68:631-639. [PMID: 31049785 DOI: 10.1007/s12031-019-01314-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 03/25/2019] [Indexed: 10/26/2022]
Abstract
It has been reported that myeloid-related protein 8/14 (MRP8/14) participates in the progression of inflammation after release from neutrophils and monocytes. This study aimed to clarify the mechanism(s) of the MRP8/14-augmented inflammatory response in mice with pneumococcal meningitis. Streptococcus pneumoniae (SP) meningitis was established by intracerebral injection of SP suspension. Balb/c mice were randomly divided into four groups and received the following injections: phosphate-buffer saline (PBS), MRP8/14 alone, SP alone, and SP plus MRP8/14. At 6 h, 24 h and 48 h postinfection, the clinical disease status was measured by the modified neurological severity score test, body weight loss and degree of cerebral edema; mice were anaesthetized, blood samples and brain samples were collected and brain inflammation was detected by haematoxylin and eosin (HE) staining; tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP) and monocyte chemoattractant protein-1 (MCP-1) levels in serum and brain homogenates were assessed by an enzyme-linked immunosorbent assay (ELISA), and the mRNA levels of the above cytokines in brain homogenates were measured by polymerase chain reaction (PCR); and the expression of nuclear factor-kappa B (NF-κB) p65 in brain tissues was determined by immunohistochemical assay. In this study, we identified that MRP8/14 substantially augmented the SP-stimulated inflammatory response, aggravated clinical disease status and exacerbated SP-induced brain edema in a murine model of pneumococcal meningitis. Exogenous administration of MRP8/14 significantly enhanced mRNA and protein expression of the proinflammatory cytokines and chemokines TNF-α, CRP, IL-6 and MCP-1 in brain homogenates and serum from mice with pneumococcal meningitis, which may be related to the NF-κB signalling pathway. We further found that MRP8/14 strongly augmented SP-induced phosphorylation of NF-κB p65 in brain tissue slices from the same model. In conclusion, our results indicated that MRP8/14 augmented the inflammatory response in mice with pneumococcal meningitis and contributed to the development of disease, which was probably through NF-κB signalling pathway activation.
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20
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Blood‒Brain Barrier Pathology and CNS Outcomes in Streptococcus pneumoniae Meningitis. Int J Mol Sci 2018; 19:ijms19113555. [PMID: 30423890 PMCID: PMC6275034 DOI: 10.3390/ijms19113555] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 11/05/2018] [Accepted: 11/09/2018] [Indexed: 12/20/2022] Open
Abstract
Streptococcus pneumoniae is a major meningitis-causing pathogen globally, bringing about significant morbidity and mortality, as well as long-term neurological sequelae in almost half of the survivors. Subsequent to nasopharyngeal colonisation and systemic invasion, translocation across the blood‒brain barrier (BBB) by S. pneumoniae is a crucial early step in the pathogenesis of meningitis. The BBB, which normally protects the central nervous system (CNS) from deleterious molecules within the circulation, becomes dysfunctional in S. pneumoniae invasion due to the effects of pneumococcal toxins and a heightened host inflammatory environment of cytokines, chemokines and reactive oxygen species intracranially. The bacteria‒host interplay within the CNS likely determines not only the degree of BBB pathological changes, but also host survival and the extent of neurological damage. This review explores the relationship between S. pneumoniae bacteria and the host inflammatory response, with an emphasis on the BBB and its roles in CNS protection, as well as both the acute and long-term pathogenesis of meningitis.
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Muri L, Grandgirard D, Buri M, Perny M, Leib SL. Combined effect of non-bacteriolytic antibiotic and inhibition of matrix metalloproteinases prevents brain injury and preserves learning, memory and hearing function in experimental paediatric pneumococcal meningitis. J Neuroinflammation 2018; 15:233. [PMID: 30131074 PMCID: PMC6103863 DOI: 10.1186/s12974-018-1272-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 08/08/2018] [Indexed: 12/04/2022] Open
Abstract
BACKGROUND Pneumococcal meningitis is associated with high mortality and morbidity rates. Up to 50% of survivors show neurologic sequelae including hearing loss, cognitive impairments and learning disabilities, being particularly detrimental in affected infants and children where adjuvant therapy with dexamethasone has no proven beneficial effect. We evaluated the effect of concomitantly targeting specific pathophysiological mechanisms responsible for brain damage-i.e. matrix-metalloproteinase (MMP) activity and the exacerbated cerebral inflammation provoked through antibiotic-induced bacterial lysis. Here, we combined adjunctive therapies previously shown to be neuroprotective when used as single adjuvant therapies. METHODS Eleven-day-old Wistar rats were infected intracisternally with 6.44 ± 2.17 × 103 CFU Streptococcus pneumoniae and randomised for treatment with ceftriaxone combined with (a) single adjuvant therapy with daptomycin (n = 24), (b) single adjuvant therapy with Trocade (n = 24), (c) combined adjuvant therapy (n = 66) consisting of daptomycin and Trocade, or (d) ceftriaxone monotherapy (n = 42). Clinical parameters and inflammatory CSF cytokine levels were determined during acute meningitis. Cortical damage and hippocampal apoptosis were assessed 42 h after infection. Morris water maze and auditory brainstem responses were used to assess neurofunctional outcome 3 weeks after infection. RESULTS We found significantly reduced apoptosis in the hippocampal subgranular zone in infant rats receiving adjuvant Trocade (p < 0.01) or combined adjuvant therapy (p < 0.001). Cortical necrosis was significantly reduced in rats treated with adjuvant daptomycin (p < 0.05) or combined adjuvant therapy (p < 0.05) compared to ceftriaxone monotherapy. Six hours after treatment initiation, CSF cytokine levels were significantly reduced for TNF-α (p < 0.01), IL-1β (p < 0.01), IL-6 (p < 0.001) and IL-10 (p < 0.01) in animals receiving combined adjuvant intervention compared to ceftriaxone monotherapy. Importantly, combined adjuvant therapy significantly improved learning and memory performance in infected animals and reduced hearing loss (77.14 dB vs 60.92 dB, p < 0.05) by preserving low frequency hearing capacity, compared to ceftriaxone monotherapy. CONCLUSION Combined adjuvant therapy with the non-bacteriolytic antibiotic daptomycin and the MMP inhibitor Trocade integrates the neuroprotective effects of both single adjuvants in experimental paediatric pneumococcal meningitis by reducing neuroinflammation and brain damage, thereby improving neurofunctional outcome. This strategy represents a promising therapeutic option to improve the outcome of paediatric patients suffering from pneumococcal meningitis.
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Affiliation(s)
- Lukas Muri
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001 Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences (GCB), University of Bern, Freiestrasse 1, 3012 Bern, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001 Bern, Switzerland
| | - Michelle Buri
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001 Bern, Switzerland
| | - Michael Perny
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001 Bern, Switzerland
| | - Stephen L. Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, 3001 Bern, Switzerland
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de Queiroz KB, dos Santos Fontes Pereira T, Araújo MSS, Gomez RS, Coimbra RS. Resveratrol Acts Anti-Inflammatory and Neuroprotective in an Infant Rat Model of Pneumococcal Meningitis by Modulating the Hippocampal miRNome. Mol Neurobiol 2018; 55:8869-8884. [DOI: 10.1007/s12035-018-1037-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 03/23/2018] [Indexed: 12/21/2022]
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23
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Xu D, Lian D, Wu J, Liu Y, Zhu M, Sun J, He D, Li L. Brain-derived neurotrophic factor reduces inflammation and hippocampal apoptosis in experimental Streptococcus pneumoniae meningitis. J Neuroinflammation 2017; 14:156. [PMID: 28778220 PMCID: PMC5545027 DOI: 10.1186/s12974-017-0930-6] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 07/27/2017] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Streptococcus pneumoniae meningitis is a serious inflammatory disease of the central nervous system (CNS) and is associated with high morbidity and mortality rates. The inflammatory processes initiated by recognition of bacterial components contribute to apoptosis in the hippocampal dentate gyrus. Brain-derived neurotrophic factor (BDNF) has long been recommended for the treatment of CNS diseases due to its powerful neuro-survival properties, as well as its recently reported anti-inflammatory and anti-apoptotic effects in vitro and in vivo. METHODS In this study, we investigated the effects of BDNF-related signaling on the inflammatory response and hippocampal apoptosis in experimental models of pneumococcal meningitis. Pretreatment with exogenous BDNF or the tropomyosin-receptor kinase B (TrkB) inhibitor k252a was performed to assess the activation or inhibition of the BDNF/TrkB-signaling axis prior to intracisternal infection with live S. pneumoniae. At 24 h post-infection, rats were assessed for clinical severity and sacrificed to harvest the brains. Paraffin-embedded brain sections underwent hematoxylin and eosin staining to evaluate pathological severity, and cytokine and chemokine levels in the hippocampus and cortex were evaluated by enzyme-linked immunosorbent assay. Additionally, apoptotic neurons were detected in the hippocampal dentate gyrus by terminal deoxynucleotidyl transferase dUTP-nick-end labeling, key molecules associated with the related signaling pathway were analyzed by real-time polymerase chain reaction and western blot, and the DNA-binding activity of nuclear factor kappa B (NF-κB) was measured by electrophoretic mobility shift assay. RESULTS Rats administered BDNF exhibited reduced clinical impairment, pathological severity, and hippocampal apoptosis. Furthermore, BDNF pretreatment suppressed the expression of inflammatory factors, including tumor necrosis factor α, interleukin (IL)-1β, and IL-6, and increased the expression of the anti-inflammatory factor IL-10. Moreover, BDNF pretreatment increased TrkB expression, activated downstream phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling, and inhibited the myeloid differentiation primary response gene 88 (MyD88)/NF-κB-signaling pathway. CONCLUSIONS These data suggested that BDNF administration exerted anti-inflammatory and anti-apoptotic effects on an experimental pneumococcal meningitis model via modulation of MyD88/NF-κB- and PI3K/AKT-signaling pathways. Our results indicated that treatment with exogenous BDNF might constitute a potential therapeutic strategy for the treatment of bacterial meningitis.
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Affiliation(s)
- Danfeng Xu
- Department of Pediatric Neurology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Kongjiang Rd 1665, Shanghai, 200092, People's Republic of China
| | - Di Lian
- Department of Pediatric Neurology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Kongjiang Rd 1665, Shanghai, 200092, People's Republic of China
| | - Jing Wu
- Department of Pediatric Neurology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Kongjiang Rd 1665, Shanghai, 200092, People's Republic of China
| | - Ying Liu
- Department of Clinical Laboratory, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, 200092, People's Republic of China
| | - Mingjie Zhu
- Department of Pathology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, 200092, People's Republic of China
| | - Jiaming Sun
- Department of Pathology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, 200092, People's Republic of China
| | - Dake He
- Department of Pediatric Neurology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Kongjiang Rd 1665, Shanghai, 200092, People's Republic of China
| | - Ling Li
- Department of Pediatric Neurology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine, Kongjiang Rd 1665, Shanghai, 200092, People's Republic of China.
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Chen X, Li Y, Blankson S, Liu M, Huang D, Redmond HP, Huang J, Wang JH, Wang J. B7-H3 Augments Inflammatory Responses and Exacerbates Brain Damage via Amplifying NF-κB p65 and MAPK p38 Activation during Experimental Pneumococcal Meningitis. PLoS One 2017; 12:e0171146. [PMID: 28141831 PMCID: PMC5283727 DOI: 10.1371/journal.pone.0171146] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 01/15/2017] [Indexed: 11/18/2022] Open
Abstract
The costimulatory protein B7-H3 has been shown to play a contributory role in the development and progression of experimental pneumococcal meningitis by augmentation of the innate immunity-associated inflammatory response via a TLR2-dependent manner. This study aimed to clarify the component(s) of TLR2-mediated signal transduction pathways responsible for B7-H3-augmented inflammatory response and subsequent brain damage during experimental pneumococcal meningitis. Administration of B7-H3 did not augment expression of TLR2 and other TLR2 upstream components, but led to an enhanced formation of MyD88-IRAK immunocomplex in the brain of S. pneumoniae-infected mice. Furthermore, B7-H3 substantially augmented S. pneumoniae-induced activation of TLR2 downstream NF-κB p65 and MAPK p38 pathways in the brain of S. pneumoniae-infected mice. Notably, blockage of NF-κB p65 and/or MAPK p38 with their specific inhibitors strongly attenuated B7-H3-amplified inflammatory response with significantly reduced proinflammatory cytokine and chemokine production, and markedly ameliorated B7-H3-exacerbated disruption of blood-brain barrier and severity of disease status in S. pneumoniae-infected mice. These results indicate that targeting NF-κB p65 and/or MAPK p38 may represent a promising therapeutic option for amelioration of overwhelming inflammatory response-associated brain injury frequently observed during pneumococcal meningitis.
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Affiliation(s)
- Xuqin Chen
- Department of Neurology, Children’s Hospital of Soochow University, Suzhou, China
- Pediatric Research Institute of Soochow University, Suzhou, China
| | - Yan Li
- Department of Neurology, Children’s Hospital of Soochow University, Suzhou, China
| | - Siobhan Blankson
- Department of Academic Surgery, University College Cork, Cork University Hospital, Cork, Ireland
| | - Min Liu
- Department of Neurology, Children’s Hospital of Soochow University, Suzhou, China
| | - Danping Huang
- Department of Neurology, Children’s Hospital of Soochow University, Suzhou, China
| | - H. Paul Redmond
- Department of Academic Surgery, University College Cork, Cork University Hospital, Cork, Ireland
| | - Jing Huang
- Department of Neurology, Children’s Hospital of Soochow University, Suzhou, China
| | - Jiang Huai Wang
- Department of Academic Surgery, University College Cork, Cork University Hospital, Cork, Ireland
- * E-mail: (WJ); (JHW)
| | - Jian Wang
- Pediatric Research Institute of Soochow University, Suzhou, China
- * E-mail: (WJ); (JHW)
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Peng L, Fan J, Tong C, Xie Z, Zhao C, Liu X, Zhu Y, Liu B. An ultrasensitive fluorescence method suitable for quantitative analysis of mung bean nuclease and inhibitor screening in vitro and vivo. Biosens Bioelectron 2016; 83:169-76. [DOI: 10.1016/j.bios.2016.04.052] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Revised: 04/10/2016] [Accepted: 04/18/2016] [Indexed: 02/02/2023]
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Lian D, He D, Wu J, Liu Y, Zhu M, Sun J, Chen F, Li L. Exogenous BDNF increases neurogenesis in the hippocampus in experimental Streptococcus pneumoniae meningitis. J Neuroimmunol 2016; 294:46-55. [PMID: 27138098 DOI: 10.1016/j.jneuroim.2016.03.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 02/24/2016] [Accepted: 03/22/2016] [Indexed: 12/15/2022]
Abstract
BACKGROUND Despite the effective use of antibiotics, occurrences of mortality and neurological sequelae following Streptococcus pneumoniae meningitis remain high. METHODS We investigated the neurogenesis of endogenous neural stem cells (NSCs) after inoculation with exogenous brain-derived neurotrophic factor (BDNF) in the hippocampus dentate gyrus following experimental S. pneumoniae meningitis using a double-labeling immunofluorescence analysis with 5-bromo-2'-deoxyuridine (BrdU), Nestin, DCX and NeuN. RESULTS Our results showed that 7days after inoculation, the number of BrdU & Nestin co-labeled cells increased in the hippocampus in meningitis rats compared with control rats (p<0.05). But the number of DCX-positive cells decreased in the dentate gyrus of infected rats treated with saline (p<0.05). However, these cell numbers returned to close to normal-control levels in infected rats treated with BDNF (p>0.05). After treatment with exogenous BDNF, the number of BrdU & Nestin co-labeled cells increased in the hippocampus in both the meningitis rats and normal control rats (p<0.05), but this increase was more significant in the former (p<0.05). We found that the percentage of BrdU & DCX/BrdU co-labeled cells increased in infected rats treated with BDNF both 7days and 14days after inoculation in a greater proportion compared to other groups (p<0.05). No significant differences were found in the percentage of BrdU & NeuN/BrdU 28days after inoculation among all of the groups (p>0.05). CONCLUSION Our findings suggest that S. pneumoniae meningitis activates the proliferation of endogenous NSCs, but impairs their early differentiation. Administration of exogenous BDNF might improve the neurogenesis of endogenous NSCs in the hippocampus and may provide a promising therapy after bacterial meningitis.
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Affiliation(s)
- Di Lian
- Department of Pediatric Neurology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China
| | - Dake He
- Department of Pediatric Neurology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China
| | - Jing Wu
- Department of Pediatric Neurology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China
| | - Ying Liu
- Department of Clinical Laboratory, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China
| | - Mingjie Zhu
- Department of Pathology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China
| | - Jiaming Sun
- Department of Pathology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China
| | - Feng Chen
- Department of Clinical Laboratory, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China
| | - Ling Li
- Department of Pediatric Neurology, Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, China.
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Lack of Proinflammatory Cytokine Interleukin-6 or Tumor Necrosis Factor Receptor-1 Results in a Failure of the Innate Immune Response after Bacterial Meningitis. Mediators Inflamm 2016; 2016:7678542. [PMID: 27057100 PMCID: PMC4749820 DOI: 10.1155/2016/7678542] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 01/04/2016] [Indexed: 12/27/2022] Open
Abstract
The most frequent pathogen that causes bacterial meningitis is the Gram-positive bacterium Streptococcus pneumoniae. By entering the brain, host cells will be activated and proinflammatory cytokines like interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) are released. The goal of the current study was to examine the interaction between IL-6 and TNFR1 as receptor for TNF-α and the innate immune response in vivo in a model of Streptococcus pneumoniae-induced meningitis. For the experiments IL-6(-/-), TNFR1(-/-), and TNFR1-IL-6(-/-) KO mice were used. Our results revealed higher mortality rates and bacterial burden after infection in TNFR1(-/-), IL-6(-/-), and TNFR1-IL-6(-/-) mice and a decreased immune response including lower neutrophil infiltration in the meninges of TNFR1(-/-) and TNFR1-IL-6(-/-) mice in contrast to IL-6(-/-) and wild type mice. Furthermore, the increased mortality of TNFR1(-/-) and TNFR1-IL-6(-/-) mice correlated with decreased glial cell activation compared to IL-6(-/-) or wild type mice after pneumococcal meningitis. Altogether, the results show the importance of TNFR1 and IL-6 in the regulation of the innate immune response. The lack of TNFR1 and IL-6 results in higher mortality by weakened immune defence, whereas the lack of TNFR1 results in more severe impairment of the innate immune response than the lack of IL-6 alone.
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Pettini E, Fiorino F, Cuppone AM, Iannelli F, Medaglini D, Pozzi G. Interferon-γ from Brain Leukocytes Enhances Meningitis by Type 4 Streptococcus pneumoniae. Front Microbiol 2015; 6:1340. [PMID: 26648922 PMCID: PMC4664635 DOI: 10.3389/fmicb.2015.01340] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 11/16/2015] [Indexed: 11/29/2022] Open
Abstract
Streptococcus pneumoniae is the leading cause of bacterial meningitis. Pneumococcal meningitis is a life-threatening disease with high rates of mortality and neurological sequelae. Immune targeting of S. pneumoniae is essential for clearance of infection; however, within the brain, the induced inflammatory response contributes to pathogenesis. In this study we investigate the local inflammatory response and the role of IFN-γ in a murine model of pneumococcal meningitis induced by intracranial injection of type 4 S. pneumoniae. Lymphoid and myeloid cell populations involved in meningitis, as well as cytokine gene expression, were investigated after infection. Animals were treated with a monoclonal antibody specific for murine IFN-γ to evaluate its role in animal survival. Intracranial inoculation of 3 × 104 colony-forming units of type 4 strain TIGR4 caused 75% of mice to develop meningitis within 4 days. The amount of lymphocytes, NK cells, neutrophils, monocytes and macrophages in the brain increased 48 h post infection. IFN-γ mRNA levels were about 240-fold higher in brains of infected mice compared to controls. Pro-inflammatory cytokines such as IL-1β and TNF-α, and TLR2 were also upregulated. In vivo treatment with anti-IFN-γ antibody increased survival of infected mice. This study shows that IFN-γ produced during meningitis by type 4 S. pneumoniae enhances bacterial pathogenesis exerting a negative effect on the disease outcome.
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Affiliation(s)
- Elena Pettini
- Laboratorio di Microbiologia Molecolare e Biotecnologia, Dipartimento di Biotecnologie Mediche, Università degli Studi di Siena Siena, Italy
| | - Fabio Fiorino
- Laboratorio di Microbiologia Molecolare e Biotecnologia, Dipartimento di Biotecnologie Mediche, Università degli Studi di Siena Siena, Italy
| | - Anna Maria Cuppone
- Laboratorio di Microbiologia Molecolare e Biotecnologia, Dipartimento di Biotecnologie Mediche, Università degli Studi di Siena Siena, Italy
| | - Francesco Iannelli
- Laboratorio di Microbiologia Molecolare e Biotecnologia, Dipartimento di Biotecnologie Mediche, Università degli Studi di Siena Siena, Italy
| | - Donata Medaglini
- Laboratorio di Microbiologia Molecolare e Biotecnologia, Dipartimento di Biotecnologie Mediche, Università degli Studi di Siena Siena, Italy
| | - Gianni Pozzi
- Laboratorio di Microbiologia Molecolare e Biotecnologia, Dipartimento di Biotecnologie Mediche, Università degli Studi di Siena Siena, Italy
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Liechti FD, Grandgirard D, Leib SL. Bacterial meningitis: insights into pathogenesis and evaluation of new treatment options: a perspective from experimental studies. Future Microbiol 2015; 10:1195-213. [PMID: 26119836 DOI: 10.2217/fmb.15.43] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Bacterial meningitis is associated with high mortality and morbidity rates. Bacterial components induce an overshooting inflammatory reaction, eventually leading to brain damage. Pathological correlates of neurofunctional deficits include cortical necrosis, damage of the inner ear and hippocampal apoptosis. The hippocampal dentate gyrus is important for memory acquisition and harbors a neuronal stem cell niche, thus being potentially well equipped for regeneration. Adjuvant therapies aimed at decreasing the inflammatory reaction, for example, dexamethasone, and those protecting the brain from injury have been evaluated in animal models of the disease. They include nonbacteriolytic antibiotics (e.g., daptomycin), metalloproteinase inhibitors and modulators of the immunological response, for example, granulocyte colony-stimulating factor. Increasing research interest has recently been focused on interventions aimed at supporting regenerative processes.
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Affiliation(s)
- Fabian D Liechti
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstr. 51, CH-3010 Bern, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstr. 51, CH-3010 Bern, Switzerland
| | - Stephen L Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstr. 51, CH-3010 Bern, Switzerland.,Biology Division, Spiez Laboratory, Swiss Federal Office for Civil Protection, Austrasse, CH-3700 Spiez, Switzerland
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Liechti FD, Grandgirard D, Leib SL. The antidepressant fluoxetine protects the hippocampus from brain damage in experimental pneumococcal meningitis. Neuroscience 2015; 297:89-94. [PMID: 25839149 DOI: 10.1016/j.neuroscience.2015.03.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Revised: 03/13/2015] [Accepted: 03/24/2015] [Indexed: 12/16/2022]
Abstract
BACKGROUND High mortality and morbidity rates are observed in patients with bacterial meningitis (BM) and urge for new adjuvant treatments in addition to standard antibiotic therapies. In BM the hippocampal dentate gyrus is injured by apoptosis while in cortical areas ischemic necrosis occurs. Experimental therapies aimed at reducing the inflammatory response and brain damage have successfully been evaluated in animal models of BM. Fluoxetine (FLX) is an anti-depressant of the selective serotonin reuptake inhibitors (SSRI) and was previously shown to be neuroprotective in vitro and in vivo. We therefore assessed the neuroprotective effect of FLX in experimental pneumococcal meningitis. METHODS Infant rats were infected intracisternally with live Streptococcus pneumoniae. Intraperitoneal treatment with FLX (10mgkg(-1)d(-1)) or an equal volume of NaCl was initiated 15min later. 18, 27, and 42h after infection, the animals were clinically (weight, clinical score, mortality) evaluated and subject to a cisternal puncture and inflammatory parameters (i.e., cyto-/chemokines, myeloperoxidase activity, matrix metalloproteinase concentrations) were measured in cerebrospinal fluid (CSF) samples. At 42h after infection, animals were sacrificed and the brains collected for histomorphometrical analysis of brain damage. RESULTS A significant lower number of animals treated with FLX showed relevant hippocampal apoptosis when compared to littermates (9/19 animals vs 18/23, P=0.038). A trend for less damage in cortical areas was observed in FLX-treated animals compared to controls (13/19 vs 13/23, P=ns). Clinical and inflammatory parameters were not affected by FLX treatment. CONCLUSION A significant neuroprotective effect of FLX on the hippocampus was observed in acute pneumococcal meningitis in infant rats.
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Affiliation(s)
- F D Liechti
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, CH-3010 Bern, Switzerland.
| | - D Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, CH-3010 Bern, Switzerland.
| | - S L Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Friedbühlstrasse 51, CH-3010 Bern, Switzerland; Biology Division, Spiez Laboratory, Swiss Federal Office for Civil Protection, Austrasse, Spiez CH-3700, Switzerland.
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Chen X, Wang Y, Wang Z, Yan R, Liu J, Meng X, Li Y, Wang J, Wang J. B7 homolog 3 aggravates brain injury in a murine model of Streptococcus pneumoniae-induced meningitis. Exp Ther Med 2015; 9:1984-1990. [PMID: 26136926 DOI: 10.3892/etm.2015.2333] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 02/13/2015] [Indexed: 11/08/2022] Open
Abstract
Despite the application of antibiotics, Streptococcus pneumoniae (SP)-induced meningitis continues to be a life-threatening disease with a high fatality rate and an elevated risk of serious neurological sequelae, particularly in developing countries. In this study, the contribution of the co-stimulatory molecule B7 homolog 3 (B7-H3) to the pathogenesis of experimental SP-induced meningitis was investigated. Mice were challenged with the intracerebroventricular injection of serotype 3 SP with or without B7-H3. The clinical status of mice with SP-induced meningitis was examined by body weight loss and spontaneous motor activity with neurological scoring. Coronal brain sections were analyzed by counting Nissl-positive neurons and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL)-positive cells. Protein expression of neuron-specific enolase (NSE) and S100B in brain tissues was examined with immunohistochemical staining. All experiments were performed in a randomized and blinded setting. By the intracerebroventricular injection of SP suspension, a murine model of pneumococcal meningitis was successfully established. In this SP-induced meningitis model, B7-H3 deteriorated the clinical status, as manifested by a decreased neurological score and increased body weight loss. Following the B7-H3 challenge, the number of Nissl-positive cells decreased and TUNEL-stained positive cells increased in the brain tissues of mice with SP meningitis, which demonstrates the enhancement of neuronal necrosis and apoptosis, respectively. Protein expression of NSE was decreased, while that of S100B was increased. These in vivo findings indicate that B7-H3 aggravates brain injury during the pathological process of experimental SP-induced meningitis.
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Affiliation(s)
- Xuqin Chen
- Department of Neurology, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China ; Jiangsu Key Laboratory of Translational Research and Therapy for Neuro-Psycho-Diseases, Institute of Neuroscience, Soochow University, Suzhou, Jiangsu 215006, P.R. China
| | - Yanping Wang
- Department of Neurology, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China
| | - Zhedong Wang
- Department of Neurology, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China
| | - Ruhong Yan
- Department of Clinical Laboratory, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
| | - Jie Liu
- Department of Neurology, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China
| | - Xiangying Meng
- Department of Neurology, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China
| | - Yan Li
- Department of Neurology, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China
| | - Jianghuai Wang
- Institute of Pediatric Medicine, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China
| | - Jian Wang
- Institute of Pediatric Medicine, Children's Hospital of Soochow University, Suzhou, Jiangsu 215003, P.R. China
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The matrix metalloproteinase inhibitor RS-130830 attenuates brain injury in experimental pneumococcal meningitis. J Neuroinflammation 2015; 12:43. [PMID: 25890041 PMCID: PMC4352253 DOI: 10.1186/s12974-015-0257-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 01/28/2015] [Indexed: 11/30/2022] Open
Abstract
Background Pneumococcal meningitis (PM) is characterized by high mortality and morbidity including long-term neurofunctional deficits. Neuropathological correlates of these sequelae are apoptosis in the hippocampal dentate gyrus and necrosis in the cortex. Matrix metalloproteinases (MMPs) play a critical role in the pathophysiology of PM. RS-130830 (Ro-1130830, CTS-1027) is a potent partially selective inhibitor of MMPs of a second generation and has been evaluated in clinical trials as an anti-arthritis drug. It inhibits MMPs involved in acute inflammation but has low activity against MMP-1 (interstitial collagenase), MMP-7 (matrilysin) and tumour necrosis factor α converting enzyme (TACE). Methods A well-established infant rat model of PM was used where live Streptococcus pneumoniae were injected intracisternally and antibiotic treatment with ceftriaxone was initiated 18 h post infection (hpi). Treatment with RS-130830 (75 mg/kg bis in die (bid) i.p., n = 40) was started at 3 hpi while control littermates received the vehicle (succinylated gelatine, n = 42). Results Cortical necrosis was significantly attenuated in animals treated with RS-130830, while the extent of hippocampal apoptosis was not influenced. At 18 hpi, concentrations of interleukin (IL)-1β and IL-10 were significantly lower in the cerebrospinal fluid of treated animals compared to controls. RS-130830 significantly reduced weight loss and leukocyte counts in the cerebrospinal fluid of survivors of PM. Conclusion This study identifies MMP inhibition, specifically with RS-130830, as an efficient strategy to attenuate disease severity and cortical brain injury in PM.
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Karadag-Oncel E, Cakir M, Kara A, Gonc N, Cengiz AB, Ozon A, Ciftci E, Alikasifoglu A, Ceyhan M, Kandemir N. Evaluation of hypothalamic-pituitary function in children following acute bacterial meningitis. Pituitary 2015; 18:1-7. [PMID: 24356781 DOI: 10.1007/s11102-013-0547-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Previous studies in adults and case reports in children have shown increased frequency of hypothalamo-pituitary dysfunction after infectious diseases of the central nervous system. The aim of this study was to evaluate the function of hypothalamo-pituitary axis in children with a history of bacterial meningitis. METHODS Patients diagnosed with bacterial meningitis between April 2000 and June 2011 was included. Baseline and stimulated hormonal tests were performed as required for hormonal evaluations following a diagnosis of meningitis. RESULTS Pituitary function was assessed following a period of 8-135 months (mean 53 months) after bacterial meningitis. Thirty-seven cases (27 male, 15 pubertal) with mean age of 11.1 ± 4.4 years were included. Mean height SDS was 0.01 ± 1.07 and mean BMI SDS was 0.54 ± 1.15 all patients had a SDS above -2 SD. Baseline cortisol and low dose ACTH stimulation revealed normal adrenal functions in all patients. Gonadotropin deficiency was not detected in any of the pubertal cases. Four cases (10.8%) had low IGF1 and IGFBP3 z-scores (<-2 SD) according to age, sex and Tanner stage, but peak GH response in clonidin test was >10 ng/ml in three of them suggesting neurosecretary dysfunction of GH in these cases. The fourth case has died before the test. No one had TSH deficiency and diabetes insipidus, only one case had mild hyperprolactinemia. CONCLUSIONS Our findings suggest that hypothalamo-pituitary dysfunction is not as common in childhood as in adulthood. The most remarkable finding was neurosecretary dysfunction of GH in some cases.
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Affiliation(s)
- Eda Karadag-Oncel
- Department of Pediatric Infectious Disease, Faculty of Medicine, Hacettepe University, Sıhhiye, 06100, Ankara, Turkey,
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Ricci S, Grandgirard D, Wenzel M, Braccini T, Salvatore P, Oggioni MR, Leib SL, Koedel U. Inhibition of matrix metalloproteinases attenuates brain damage in experimental meningococcal meningitis. BMC Infect Dis 2014; 14:726. [PMID: 25551808 PMCID: PMC4300156 DOI: 10.1186/s12879-014-0726-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 12/18/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Approximately 7% of survivors from meningococcal meningitis (MM) suffer from neurological sequelae due to brain damage in the course of meningitis. The present study focuses on the role of matrix metalloproteinases (MMPs) in a novel mouse model of MM-induced brain damage. METHODS The model is based on intracisternal infection of BALB/c mice with a serogroup C Neisseria meningitidis strain. Mice were infected with meningococci and randomised for treatment with the MMP inhibitor batimastat (BB-94) or vehicle. Animal survival, brain injury and host-response biomarkers were assessed 48 h after meningococcal challenge. RESULTS Mice that received BB-94 presented significantly diminished MMP-9 levels (p < 0.01), intracerebral bleeding (p < 0.01), and blood-brain barrier (BBB) breakdown (p < 0.05) in comparison with untreated animals. In mice suffering from MM, the amount of MMP-9 measured by zymography significantly correlated with both intracerebral haemorrhage (p < 0.01) and BBB disruption (p < 0.05). CONCLUSIONS MMPs significantly contribute to brain damage associated with experimental MM. Inhibition of MMPs reduces intracranial complications in mice suffering from MM, representing a potential adjuvant strategy in MM post-infection sequelae.
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Liu X, Han Q, Leng J. Analysis of nucleotide-binding oligomerization domain proteins in a murine model of pneumococcal meningitis. BMC Infect Dis 2014; 14:648. [PMID: 25443778 PMCID: PMC4256814 DOI: 10.1186/s12879-014-0648-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 11/21/2014] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND The innate immune system recognizes pathogens via its pattern recognition receptors. The objective of this study was to investigate the role of the nucleotide-binding oligomerization domain (NOD) proteins, a family of the novel bacterial pattern recognition receptors, in host responses to the gram-positive bacteria Streptococcus pneumoniae. METHODS Sprague-Dawley rats were infected via intracisternal injections of viable S. pneumoniae, and rats in the control group were injected with sterile saline. After infection, real-time PCR was performed to determine the presence of mRNAs encoding NOD1 and NOD2. Quantitative analyses of the NOD1, NOD2 and NF-kB proteins were also performed western blotting following challenge infections with viable S. pneumoniae. The TNF-α and IL-6 levels in brain homogenates were evaluated using enzyme-linked immunosorbent assays (ELISAs). RESULTS The results revealed up-regulations of the mRNA and protein levels of NOD2 within the CNS of rats with S. pneumoniae meningitis. Moreover, the activation of NF-κB in the brain tissues following infection with live S. pneumoniae was also significantly increased, which indicates that NOD2 mediated NF-κB activation in experimental pneumococcal meningitis. Similarly, TNF-α and IL-6 levels were increased in the brain following in vivo S. pneumoniae administration. CONCLUSIONS These results suggest that NOD2 is involved in the host response to the gram-positive bacteria S. pneumoniae in the CNS and that NOD2 might play an important role in the initiation and/or progression of CNS inflammation associated with pneumococcal meningitis.
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Affiliation(s)
- Xinjie Liu
- Department of Pediatrics, Qilu Hospital, Shandong University, No. 107 Wen Hua Xi Road, Jinan, People's Republic of China. .,Brain Science Research Institute, Shandong University, No. 107 Wen Hua Xi Road, Jinan, People's Republic of China.
| | - Qizheng Han
- Department of Respiratory Medicine, Provincial Hospital Affiliated to Shandong University, No. 4 Duan Xing Xi Road, Jinan, People's Republic of China.
| | - Junhong Leng
- Department of Ultrasonic Diagnosis, Jinan Maternity and Children Care Hospital, Jian Guo Xiao Jing San Road, Jinan, People's Republic of China.
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Liechti FD, Stüdle N, Theurillat R, Grandgirard D, Thormann W, Leib SL. The mood-stabilizer lithium prevents hippocampal apoptosis and improves spatial memory in experimental meningitis. PLoS One 2014; 9:e113607. [PMID: 25409333 PMCID: PMC4237452 DOI: 10.1371/journal.pone.0113607] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 10/28/2014] [Indexed: 12/20/2022] Open
Abstract
Pneumococcal meningitis is associated with high morbidity and mortality rates. Brain damage caused by this disease is characterized by apoptosis in the hippocampal dentate gyrus, a morphological correlate of learning deficits in experimental paradigms. The mood stabilizer lithium has previously been found to attenuate brain damage in ischemic and inflammatory diseases of the brain. An infant rat model of pneumococcal meningitis was used to investigate the neuroprotective and neuroregenerative potential of lithium. To assess an effect on the acute disease, LiCl was administered starting five days prior to intracisternal infection with live Streptococcus pneumoniae. Clinical parameters were recorded, cerebrospinal fluid (CSF) was sampled, and the animals were sacrificed 42 hours after infection to harvest the brain and serum. Cryosections of the brains were stained for Nissl substance to quantify brain injury. Hippocampal gene expression of Bcl-2, Bax, p53, and BDNF was analyzed. Lithium concentrations were measured in serum and CSF. The effect of chronic lithium treatment on spatial memory function and cell survival in the dentate gyrus was evaluated in a Morris water maze and by quantification of BrdU incorporation after LiCl treatment during 3 weeks following infection. In the hippocampus, LiCl significantly reduced apoptosis and gene expression of Bax and p53 while it increased expression of Bcl-2. IL-10, MCP-1, and TNF were significantly increased in animals treated with LiCl compared to NaCl. Chronic LiCl treatment improved spatial memory in infected animals. The mood stabilizer lithium may thus be a therapeutic alternative to attenuate neurofunctional deficits as a result of pneumococcal meningitis.
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Affiliation(s)
- Fabian D. Liechti
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | - Nicolas Stüdle
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Regula Theurillat
- Clinical Pharmacology Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Denis Grandgirard
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Wolfgang Thormann
- Clinical Pharmacology Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Stephen L. Leib
- Neuroinfection Laboratory, Institute for Infectious Diseases, University of Bern, Bern, Switzerland
- Biology Division, Spiez Laboratory, Swiss Federal Office for Civil Protection, Spiez, Switzerland
- * E-mail:
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Barichello T, Generoso JS, Simões LR, Steckert AV, Moreira AP, Dominguini D, Ferrari P, Gubert C, Kapczinski F, Jornada LK, Danielski LG, Petronilho F, Budni J, Quevedo J. Folic acid prevented cognitive impairment in experimental pneumococcal meningitis. J Neural Transm (Vienna) 2014; 122:643-51. [DOI: 10.1007/s00702-014-1302-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Accepted: 08/22/2014] [Indexed: 12/19/2022]
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Predictive value of cerebrospinal fluid matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 concentrations in childhood bacterial meningitis. Pediatr Infect Dis J 2014; 33:675-9. [PMID: 24445831 DOI: 10.1097/inf.0000000000000249] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Increased concentrations of matrix metalloproteinases (MMP) in cerebrospinal fluid are part of the host response in bacterial meningitis (BM). We investigated whether the concentrations of MMP-9 and the tissue inhibitor of metalloproteinase (TIMP)-1 predict the outcome in childhood BM. METHODS Cerebrospinal fluid MMP-9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) were quantified by an enzyme-linked immunosorbent assay from 264 and 335 patients, respectively; 43 children without BM served as controls. The results were compared with previously known independent predictors of death and sequelae. RESULTS Higher MMP-9 and TIMP-1 values distinguished the controls from the BM patients (P < 0.0001). A MMP-9 concentration >940 ng/mL proved an independent predictor of death [adjusted odds ratio: 4.03; 95% confidence interval (CI): 2.09-7.77; P < 0.0001]. If the patient additionally presented with a Glasgow Coma Score below 9, the odds increased to 13.21 (95% CI: 5.44-32.08; P < 0.0001). TIMP-1 levels correlated with the severity of sequelae (ρ: 0.30; P < 0.0001), but not with death. Its concentration above 390 ng/mL increased the likelihood of sequelae 3.43-fold (95% CI: 1·73-6·79; P = 0.0004), and up to 31.18-fold (95% CI: 4.05-239.8; P = 0.0009) if the patient also presented a Glasgow Coma Score < 12. CONCLUSIONS Elevated cerebrospinal fluid MMP-9 and TIMP-1 values predict 2 important outcomes in childhood BM. Combined with a clinical evaluation, quantification of these indices augments the chances to identify the patients in greatest need of better treatment modalities.
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Holler JG, Brandt CT, Leib SL, Rowland IJ, Østergaard C. Increase in hippocampal water diffusion and volume during experimental pneumococcal meningitis is aggravated by bacteremia. BMC Infect Dis 2014; 14:240. [PMID: 24886045 PMCID: PMC4016615 DOI: 10.1186/1471-2334-14-240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2014] [Accepted: 04/25/2014] [Indexed: 11/22/2022] Open
Abstract
Background The hippocampus undergoes apoptosis in experimental pneumococcal meningitis leading to neurofunctional deficits in learning and memory function. The aim of the present study was 1) to investigate hippocampal apparent diffusion coefficient (ADC) and volume with MRI during the course of experimental pneumococcal meningitis, 2) to explore the influence of accompanying bacteremia on hippocampal water distribution and volume, 3) and to correlate these findings to the extent of apoptosis in the hippocampus. Methods Experimental meningitis in rats was induced by intracisternal injection of live pneumococci. The study comprised of four experimental groups. I. Uninfected controls (n = 8); II. Meningitis (n = 11); III. Meningitis with early onset bacteremia by additional i.v. injection of live pneumococci (n = 10); IV. Meningitis with attenuated bacteremia by treatment with serotype-specific anti-pneumococcal antibodies (n = 14). T2 and diffusion weighted MR images were used to analyze changes in hippocampus volume and water diffusion (ADC). The results were correlated to ADC of the cortex, to ventricular volume, and to the extent of hippocampal apoptosis. Results Both ADC and the volume of hippocampus were significantly increased in meningitis rats compared to uninfected controls (Kruskal-Wallis test, p = 0.0001, Dunns Post Test, p < 0.05), and were significantly increased in meningitis rats with an early onset bacteremia as compared to meningitis rats with attenuated bacteremia (p < 0.05). Hippocampal ADC and the volume and size of brain ventricles were positively correlated (Spearman Rank, p < 0.05), whereas no association was found between ADC or volume and the extent of apoptosis (p > 0.05). Conclusions In experimental meningitis increase in volume and water diffusion of the hippocampus are significantly associated with accompanying bacteremia.
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Affiliation(s)
- Jon G Holler
- Department of Infectious Diseases, Copenhagen University Hospital Hvidovre, Kettegaard Alle 30, Hvidovre, Copenhagen 2650, Denmark.
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Barichello T, Simões LR, Generoso JS, Sangiogo G, Danielski LG, Florentino D, Dominguini D, Comim CM, Petronilho F, Quevedo J. Erythropoietin prevents cognitive impairment and oxidative parameters in Wistar rats subjected to pneumococcal meningitis. Transl Res 2014; 163:503-13. [PMID: 24440628 DOI: 10.1016/j.trsl.2013.12.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 12/19/2013] [Accepted: 12/21/2013] [Indexed: 01/29/2023]
Abstract
Pneumococcal meningitis is characterized by a severe inflammatory reaction in the subarachnoid and ventricular space of the brain, disruption of the blood-brain barrier, hearing loss, and neurologic sequelae in as many as 27% of surviving patients. Several experimental studies have shown that erythropoietin (EPO) and its receptor are expressed in the central nervous system and have neuroprotective properties through the inhibition of apoptosis, as well as anti-inflammatory, antioxidant, angiogenic, and neurotrophic effects. In the current study, we demonstrated the effect of erythropoietin (EPO) on lipid peroxidation, protein carbonylation, superoxide dismutase (SOD), catalase (CAT), myeloperoxidase (MPO), and behavioral parameters in rats with pneumococcal meningitis. EPO decreased lipid peroxidation and protein carbonylation, and it prevented protein degradation in the hippocampus and frontal cortex. MPO activity was decreased, and both SOD and CAT activity were increased in the first 6 hours after pneumococcal meningitis induction. Novel object recognition memory was impaired in the meningitis group; however, adjuvant treatment with EPO prevented memory impairment during both the short- and long-term retention tests. The meningitis group showed no difference in motor and exploratory activity between training and test sessions in the open-field task, which indicates that habituation memory was impaired; however, adjuvant treatment with EPO prevented habituation memory impairment. Although there are some limitations with respect to the animal model of pneumococcal meningitis, this study suggests that adjuvant treatment with EPO contributed to decreased oxidative stress and prevented cognitive impairment.
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Affiliation(s)
- Tatiana Barichello
- Laboratório de Microbiologia Experimental, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; Center for Experimental Models in Psychiatry, Department of Psychiatry and Behavioral Sciences, The University of Texas Medical School at Houston, Houston, TX, USA.
| | - Lutiana R Simões
- Laboratório de Microbiologia Experimental, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Jaqueline S Generoso
- Laboratório de Microbiologia Experimental, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Gustavo Sangiogo
- Laboratório de Microbiologia Experimental, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Lucineia Gainski Danielski
- Laboratório de Fisiopatologia Clínica e Experimental, Programa de Pós-Graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina, Tubarão, SC, Brazil
| | - Drielly Florentino
- Laboratório de Fisiopatologia Clínica e Experimental, Programa de Pós-Graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina, Tubarão, SC, Brazil
| | - Diogo Dominguini
- Laboratório de Neurociências, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil
| | - Clarissa M Comim
- Laboratório de Neurociências Experimental, Programa de Pós-Graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina, Palhoça, SC, Brazil
| | - Fabricia Petronilho
- Laboratório de Fisiopatologia Clínica e Experimental, Programa de Pós-Graduação em Ciências da Saúde, Universidade do Sul de Santa Catarina, Tubarão, SC, Brazil
| | - João Quevedo
- Laboratório de Neurociências, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil; Center for Experimental Models in Psychiatry, Department of Psychiatry and Behavioral Sciences, The University of Texas Medical School at Houston, Houston, TX, USA
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Matrix metalloproteinase inhibition lowers mortality and brain injury in experimental pneumococcal meningitis. Infect Immun 2014; 82:1710-8. [PMID: 24491581 DOI: 10.1128/iai.00073-14] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Pneumococcal meningitis (PM) results in high mortality rates and long-lasting neurological deficits. Hippocampal apoptosis and cortical necrosis are histopathological correlates of neurofunctional sequelae in rodent models and are frequently observed in autopsy studies of patients who die of PM. In experimental PM, inhibition of matrix metalloproteinases (MMPs) and/or tumor necrosis factor (TNF)-converting enzyme (TACE) has been shown to reduce brain injury and the associated impairment of neurocognitive function. However, none of the compounds evaluated in these studies entered clinical development. Here, we evaluated two second-generation MMP and TACE inhibitors with higher selectivity and improved oral availability. Ro 32-3555 (Trocade, cipemastat) preferentially inhibits collagenases (MMP-1, -8, and -13) and gelatinase B (MMP-9), while Ro 32-7315 is an efficient inhibitor of TACE. PM was induced in infant rats by the intracisternal injection of live Streptococcus pneumoniae. Ro 32-3555 and Ro 32-7315 were injected intraperitoneally, starting at 3 h postinfection. Antibiotic (ceftriaxone) therapy was initiated at 18 h postinfection, and clinical parameters (weight, clinical score, mortality rate) were recorded. Myeloperoxidase activities, concentrations of cytokines and chemokines, concentrations of MMP-2 and MMP-9, and collagen concentrations were measured in the cerebrospinal fluid. Animals were sacrificed at 42 h postinfection, and their brains were assessed by histomorphometry for hippocampal apoptosis and cortical necrosis. Both compounds, while exhibiting disparate MMP and TACE inhibitory profiles, decreased hippocampal apoptosis and cortical injury. Ro 32-3555 reduced mortality rates and cerebrospinal fluid TNF, interleukin-1β (IL-1β) and collagen levels, while Ro 32-7315 reduced weight loss and cerebrospinal fluid TNF and IL-6 levels.
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Baranger K, Rivera S, Liechti FD, Grandgirard D, Bigas J, Seco J, Tarrago T, Leib SL, Khrestchatisky M. Endogenous and synthetic MMP inhibitors in CNS physiopathology. PROGRESS IN BRAIN RESEARCH 2014; 214:313-51. [DOI: 10.1016/b978-0-444-63486-3.00014-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Zysset-Burri DC, Bellac CL, Leib SL, Wittwer M. Vitamin B6 reduces hippocampal apoptosis in experimental pneumococcal meningitis. BMC Infect Dis 2013; 13:393. [PMID: 23977941 PMCID: PMC3765858 DOI: 10.1186/1471-2334-13-393] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2013] [Accepted: 08/21/2013] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Bacterial meningitis caused by Streptococcus pneumoniae leads to death in up to 30% of patients and leaves up to half of the survivors with neurological sequelae. The inflammatory host reaction initiates the induction of the kynurenine pathway and contributes to hippocampal apoptosis, a form of brain damage that is associated with learning and memory deficits in experimental paradigms. Vitamin B6 is an enzymatic cofactor in the kynurenine pathway and may thus limit the accumulation of neurotoxic metabolites and preserve the cellular energy status. The aim of this study in a pneumococcal meningitis model was to investigate the effect of vitamin B6 on hippocampal apoptosis by histomorphology, by transcriptomics and by measurement of cellular nicotine amide adenine dinucleotide content. METHODS AND RESULTS Eleven day old Wistar rats were infected with 1x10(6) cfu/ml of S. pneumoniae and randomized for treatment with vitamin B6 or saline as controls. Vitamin B6 led to a significant (p > 0.02) reduction of hippocampal apoptosis. According to functional annotation based clustering, vitamin B6 led to down-regulation of genes involved in processes of inflammatory response, while genes encoding for processes related to circadian rhythm, neuronal signaling and apoptotic cell death were mostly up-regulated. CONCLUSIONS Our results provide evidence that attenuation of apoptosis by vitamin B6 is multi-factorial including down-modulation of inflammation, up-regulation of the neuroprotective brain-derived neurotrophic factor and prevention of the exhaustion of cellular energy stores. The neuroprotective effect identifies vitamin B6 as a potential target for the development of strategies to attenuate brain injury in bacterial meningitis.
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Affiliation(s)
- Denise C Zysset-Burri
- Biology Division, Spiez Laboratory, Federal Office for Civil Protection, Austrasse, CH-3700, Spiez, Switzerland.
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44
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Merres J, Höss J, Albrecht LJ, Kress E, Soehnlein O, Jansen S, Pufe T, Tauber SC, Brandenburg LO. Role of the cathelicidin-related antimicrobial peptide in inflammation and mortality in a mouse model of bacterial meningitis. J Innate Immun 2013; 6:205-18. [PMID: 23969854 DOI: 10.1159/000353645] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 06/06/2013] [Indexed: 12/19/2022] Open
Abstract
Antimicrobial peptides (AP) are important components of the innate immune system, yet little is known about their expression and function in the brain. Our previous work revealed upregulated gene expression of cathelicidin-related AP (CRAMP) following bacterial meningitis in primary rat glial cells as well as bactericidal activity against frequent meningitis-causing bacteria. However, the effect of cathelicidin expression on the progression of inflammation and mortality in bacterial meningitis remains unknown. Therefore, we used CRAMP-deficient mice to investigate the effect of CRAMP on bacterial growth, inflammatory responses and mortality in meningitis. Meningitis was induced by intracerebral injection of type 3 Streptococcus pneumoniae. The degree of inflammation was analyzed in various brain regions by means of immunohistochemistry and real-time RT-PCR. CRAMP deficiency led to a higher mortality rate that was associated with increased bacterial titers in the cerebellum, blood and spleen as well as decreased meningeal neutrophil infiltration. CRAMP-deficient mice displayed a higher degree of glial cell activation that was accompanied by a more pronounced proinflammatory response. Taken together, this work provides insight into the important role of CRAMP as part of the innate immune defense against pathogens in bacterial CNS infections.
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Affiliation(s)
- Julika Merres
- Department of Anatomy and Cell Biology, RWTH Aachen University, Aachen, Germany
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Omran A, Peng J, Zheng C, Xue J, Xiang QL, Yin F. The Expression of Interleukin-1b and miRNA-146a in the Cerebral Cortex of Acute Escherichia Coli Meningitis Immature Rat Model. Afr J Infect Dis 2013; 6:41-7. [PMID: 23878714 DOI: 10.4314/ajid.v6i2.3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The main limitation to advances in treatment of bacterial meningitis and its complications is the incomplete knowledge of the pathogenesis and pathophysiology of this disease. The aim of this research is to detect the expression of interleukin (IL)-1β as pro-inflammatory cytokine and miRNA (miR)-146a as post transcriptional inflammation associated microRNA (miRNA) in the cerebral cortex of acute Escherichia coli (E. coli) meningitis immature rat model. Immature rats in the post natal day 11 (PN11) were used to construct a model of acute E. coli meningitis and served as controls. The expression of IL-1β and miR-146a were detected in the cerebral cortex by reverse transcription polymerase chain reaction (RT-PCR) and real-time quantitative PCR (qPCR) analysis respectively, 24 hours after bacterial inoculation. In the cerebral cortical tissue of acute E. coli meningitis immature rat model the IL-1β expression was significantly upregulated while the miR-146a expression was significantly downregulated. This study tried to add a new insight on the molecular basis of the E. coli meningitis pathogenesis at its very early stage through detecting the expression of IL-1β and miR-146a in the cerebral cortex of the infected immature rats. Consequently, modulation of the IL-1β- miR-146a axis may be a new target for treatment of acute E. coli meningitis.
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Affiliation(s)
- Ahmed Omran
- Department of Pediatrics, Xiangya Hospital of Central South University, No. 87 Xiangya Road, Changsha, Hunan, 410008, China
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Berger J, Sprague SM, Wu Y, Davis WW, Jimenez DF, Barone CM, Ding Y. Peripheral thermal injury causes early blood–brain barrier dysfunction and matrix metalloproteinase expression in rat. Neurol Res 2013; 29:610-4. [PMID: 17535571 DOI: 10.1179/016164107x172158] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
High mortality incidence after serious systemic thermal injury is believed to be linked to significant increases in cerebral permeability, ultimately leading to irreversible blood-brain barrier (BBB) breakdown. The aim of this study was to investigate whether disruption of microvascular integrity in a rat thermal injury model is associated with early matrix metalloproteinase (MMP) expression. A total of 35 Sprague-Dawley rats were studied in thermal injury and control groups, each group containing two subgroups, one for brain edema and Evans blue analysis and another for MMP mRNA analysis. Thermally injured animals were anesthetized and submerged vertically in 85 degrees C water to the neck for 6 seconds producing a third degree burn affecting 70% of the total body surface area. BBB integrity was determined by measuring amount of Evans blue after 7 hours of injury with a spectrophotometer. Brain edema was detected by calculating water content. Brain mRNA levels were determined with real-time PCR 3 and 7 hours post-injury. Brain water content was significantly increased after peripheral injury at hour 7. Evans blue leakage was also significantly increased at the same time, suggesting an impaired BBB function after injury. Expressions of MMP-2 and MMP-9 mRNA in brain were increased as early as 3 hours after injury and remained at hour 7. Our study demonstrated a significant increase in cerebral permeability that occurs after serious systemic thermal injury. The underlying mechanisms could be related to early expression of MMPs.
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Affiliation(s)
- Jamie Berger
- Division of Plastic and Reconstructive Surgery, The University of Texas Health Science Center at San Antonio, Floyd C Drive, San Antonio, TX 78229-3900, USA
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Rosendahl A, Bergmann S, Hammerschmidt S, Goldmann O, Medina E. Lung dendritic cells facilitate extrapulmonary bacterial dissemination during pneumococcal pneumonia. Front Cell Infect Microbiol 2013; 3:21. [PMID: 23802100 PMCID: PMC3689026 DOI: 10.3389/fcimb.2013.00021] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2013] [Accepted: 06/04/2013] [Indexed: 11/16/2022] Open
Abstract
Streptococcus pneumoniae is a leading cause of bacterial pneumonia worldwide. Given the critical role of dendritic cells (DCs) in regulating and modulating the immune response to pathogens, we investigated here the role of DCs in S. pneumoniae lung infections. Using a well-established transgenic mouse line which allows the conditional transient depletion of DCs, we showed that ablation of DCs resulted in enhanced resistance to intranasal challenge with S. pneumoniae. DCs-depleted mice exhibited delayed bacterial systemic dissemination, significantly reduced bacterial loads in the infected organs and lower levels of serum inflammatory mediators than non-depleted animals. The increased resistance of DCs-depleted mice to S. pneumoniae was associated with a better capacity to restrict pneumococci extrapulmonary dissemination. Furthermore, we demonstrated that S. pneumoniae disseminated from the lungs into the regional lymph nodes in a cell-independent manner and that this direct way of dissemination was much more efficient in the presence of DCs. We also provide evidence that S. pneumoniae induces expression and activation of matrix metalloproteinase-9 (MMP-9) in cultured bone marrow-derived DCs. MMP-9 is a protease involved in the breakdown of extracellular matrix proteins and is critical for DC trafficking across extracellular matrix and basement membranes during the migration from the periphery to the lymph nodes. MMP-9 was also significantly up-regulated in the lungs of mice after intranasal infection with S. pneumoniae. Notably, the expression levels of MMP-9 in the infected lungs were significantly decreased after depletion of DCs suggesting the involvement of DCs in MMP-9 production during pneumococcal pneumonia. Thus, we propose that S. pneumoniae can exploit the DC-derived proteolysis to open tissue barriers thereby facilitating its own dissemination from the local site of infection.
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Affiliation(s)
- Alva Rosendahl
- Infection Immunology Research Group, Department of Medical Microbiology, Helmholtz Centre for Infection ResearchBraunschweig, Germany
| | - Simone Bergmann
- Institute for Microbiology, Department of Cellular Infection Biology, Technische UniversitätBraunschweig, Germany
| | - Sven Hammerschmidt
- Department Genetics of Microorganisms, Interfaculty Institute for Genetics and Functional Genomics, Ernst Moritz University of GreifswaldGreifswald, Germany
| | - Oliver Goldmann
- Infection Immunology Research Group, Department of Medical Microbiology, Helmholtz Centre for Infection ResearchBraunschweig, Germany
| | - Eva Medina
- Infection Immunology Research Group, Department of Medical Microbiology, Helmholtz Centre for Infection ResearchBraunschweig, Germany
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The causative pathogen determines the inflammatory profile in cerebrospinal fluid and outcome in patients with bacterial meningitis. Mediators Inflamm 2013; 2013:312476. [PMID: 23864766 PMCID: PMC3705964 DOI: 10.1155/2013/312476] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 05/28/2013] [Accepted: 06/04/2013] [Indexed: 11/21/2022] Open
Abstract
Background. The brain's inflammatory response to the infecting pathogen determines the outcome of bacterial meningitis (BM), for example, the associated mortality and the extent of brain injury. The inflammatory cascade is initiated by the presence of bacteria in the cerebrospinal fluid (CSF) activating resident immune cells and leading to the influx of blood derived leukocytes. To elucidate the pathomechanisms behind the observed difference in outcome between different pathogens, we compared the inflammatory profile in the CSF of patients with BM caused by Streptococcus pneumonia (n = 14), Neisseria meningitidis (n = 22), and Haemophilus influenza (n = 9). Methods. CSF inflammatory parameters, including cytokines and chemokines, MMP-9, and nitric oxide synthase activity, were assessed in a cohort of patients with BM from Burkina Faso. Results. Pneumococcal meningitis was associated with significantly higher CSF concentrations of IFN-γ, MCP-1, and the matrix-metalloproteinase (MMP-) 9. In patients with a fatal outcome, levels of TNF-α, IL-1β, IL-1RA, IL-6, and TGF-α were significantly higher. Conclusion. The signature of pro- and anti-inflammatory mediators and the intensity of inflammatory processes in CSF are determined by the bacterial pathogen causing bacterial meningitis with pneumococcal meningitis being associated with a higher case fatality rate than meningitis caused by N. meningitidis or H. influenzae.
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Hawkins KE, DeMars KM, Yang C, Rosenberg GA, Candelario-Jalil E. Fluorometric immunocapture assay for the specific measurement of matrix metalloproteinase-9 activity in biological samples: application to brain and plasma from rats with ischemic stroke. Mol Brain 2013; 6:14. [PMID: 23522154 PMCID: PMC3620676 DOI: 10.1186/1756-6606-6-14] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/19/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Matrix metalloproteinases are important factors in the molecular mechanisms leading to neuronal injury in many neurological disorders. Matrix metalloproteinase (MMP)-9 is up-regulated after cerebral ischemia and neuroinflammation and is actively involved in blood-brain barrier disruption. Current methods of measuring MMP-9 activity, such as gelatin-substrate zymography, are unspecific and arduous. Here we developed an immunocapture assay with high efficiency, specificity, and sensitivity for quantifying endogenously active as well as total MMP-9 activity. RESULTS A fluorescence resonance energy transfer (FRET) peptide-based immunocapture assay was developed that enables the accurate assessment of total and active forms of MMP-9 in complex biological samples. The FRET assay demonstrated correct and efficient binding of MMP-9 to a mouse monoclonal MMP-9 antibody and high specificity of the immunocapture antibody for MMP-9. Total and active levels of MMP-9 were measured in rat brain homogenates, plasma, human HT-1080 conditioned media, and RBE4 endothelial cell lysates. The FRET immunocapture assay yielded highly similar results for total MMP-9 activity when compared to gelatin-substrate zymography. CONCLUSIONS We suggest that the new FRET peptide-based immunocapture assay is a viable replacement of zymography for sensitive and high throughput quantification of MMP-9 activity in biological samples.
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Affiliation(s)
- Kimberly E Hawkins
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Kelly M DeMars
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Changjun Yang
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Gary A Rosenberg
- Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
| | - Eduardo Candelario-Jalil
- Department of Neuroscience, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
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Barichello T, Generoso JS, Collodel A, Moreira AP, Almeida SMD. Pathophysiology of acute meningitis caused by Streptococcus pneumoniae and adjunctive therapy approaches. ARQUIVOS DE NEURO-PSIQUIATRIA 2012; 70:366-72. [PMID: 22618789 DOI: 10.1590/s0004-282x2012000500011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Accepted: 02/12/2012] [Indexed: 11/22/2022]
Abstract
Pneumococcal meningitis is a life-threatening disease characterized by an acute purulent infection affecting piamater, arachnoid and the subarachnoid space. The intense inflammatory host's response is potentially fatal and contributes to the neurological sequelae. Streptococcus pneumoniae colonizes the nasopharynx, followed by bacteremia, microbial invasion and blood-brain barrier traversal. S. pneumoniae is recognized by antigen-presenting cells through the binding of Toll-like receptors inducing the activation of factor nuclear kappa B or mitogen-activated protein kinase pathways and subsequent up-regulation of lymphocyte populations and expression of numerous proteins involved in inflammation and immune response. Many brain cells can produce cytokines, chemokines and others pro-inflammatory molecules in response to bacteria stimuli, as consequence, polymorphonuclear are attracted, activated and released in large amounts of superoxide anion and nitric oxide, leading to the peroxynitrite formation, generating oxidative stress. This cascade leads to lipid peroxidation, mitochondrial damage, blood-brain barrier breakdown contributing to cell injury during pneumococcal meningitis.
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Affiliation(s)
- Tatiana Barichello
- Laboratório de Microbiologia Experimental, Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil.
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