Yoshiharu Nagaoka

Increase of tumor necrosis factor-α in the blood induces early activation of matrix metalloproteinase-9 in the brain

Increases of cytokine in the blood play important roles in the pathogenesis of influenza‐associated encephalopathy. TNF‐α was administered intravenously to wild‐type mice, after which blood, CSF and brain tissue were obtained, and changes in BBB permeability, the amounts of MMP‐9 and TIMP‐1, and the localization of activated MMP were assessed. There was a significant increase in BBB permeability after 6 and 12 hr. MMP‐9 was increased after 3 hr in the brain and cerebrospinal fluid, which was earlier than in the serum. TIMP‐1 protein in the brain increased significantly after MMP‐9 had increased. Activation of MMP‐9 was observed in neurons in the cerebral cortex and hippocampus, and in vascular endothelial cells. These findings suggest that an increase in blood TNF‐α promotes activation of MMP‐9 in the brain, and may also induce an increase in permeability of the BBB. Early activation of MMP‐9 in the brain may contribute to an early onset of neurological disorders and brain edema prior to multiple organ failure in those inflammatory diseases associated with highly increased concentrations of TNF‐α in the blood, such as sepsis, burns, trauma and influenza‐associated encephalopathy.

Redox-Active Protein Thioredoxin-1 Administration Ameliorates Influenza A Virus (H1N1)-Induced Acute Lung Injury in Mice

Objectives:Influenza virus infections can cause severe acute lung injury leading to significant morbidity and mortality. Thioredoxin-1 is a redox-active defensive protein induced in response to stress conditions. Animal experiments have revealed that thioredoxin-1 has protective effects against various severe disorders. This study was undertaken to evaluate the protective effects of recombinant human thioredoxin-1 administration on influenza A virus (H1N1)-induced acute lung injury in mice. Design:Prospective animal trial. Setting:Research laboratory. Subjects:Nine-week-old male C57BL/6 mice inoculated with H1N1. Intervention:The mice were divided into a vehicle-treated group and recombinant human thioredoxin-1-treated group. For survival rate analysis, the vehicle or recombinant human thioredoxin-1 was administered intraperitoneally every second day from day –1 to day 13. For lung lavage and pathological analyses, vehicle or recombinant human thioredoxin-1 was administered intraperitoneally on days –1, 1, and 3. Measurements and Main Results:Lung lavage and pathological analyses were performed at 24, 72, and 120 hrs after inoculation. The recombinant human thioredoxin-1 treatment significantly improved the survival rate of H1N1-inoculated mice, although the treatment did not affect virus propagation in the lung. The treatment significantly attenuated the histological changes and neutrophil infiltration in the lung of H1N1-inoculated mice. The treatment significantly attenuated the production of tumor necrosis factor-&agr; and chemokine (C-X-C motif) ligand 1 in the lung and oxidative stress enhancement, which were observed in H1N1-inoculated mice. H1N1 induced expressions of tumor necrosis factor-&agr; and chemokine (C-X-C motif) ligand 1 in murine lung epithelial cells MLE-12, which were inhibited by the addition of recombinant human thioredoxin-1. The recombinant human thioredoxin-1 treatment started 30 mins after H1N1 inoculation also significantly improved the survival of the mice. Conclusions:Exogenous administration of recombinant human thioredoxin-1 significantly improved the survival rate and attenuated lung histological changes in the murine model of influenza pneumonia. The protective mechanism of thioredoxin-1 might be explained by its potent antioxidative and anti-inflammatory actions. Consequently, recombinant human thioredoxin-1 might be a possible pharmacological strategy for severe influenza virus infection in humans.

Prognostic value of brain injury biomarkers in acute encephalitis/encephalopathy

Acute encephalitis/encephalopathy (AEE) is a devastating cause of severe neurodevelopmental sequelae or death in children. Assessing ongoing brain injury and predicting outcomes using bedside point‐of‐care testing is expected to be extremely valuable.

Gene expression analysis in children with complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis

Viral infections have been implicated as a cause of complex seizures in children. The pathogenic differences in complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis remain unclear. This study analyzed the gene expression profiles in the peripheral whole blood from pediatric patients with complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis. The gene expression profiles of ten patients (five with seizures and five without) with influenza A(H1N1)pdm09 and six patients (three with seizures and three without) with rotavirus gastroenteritis were examined. Gene expression profiles in the whole blood were different in complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis. Transcripts related to the immune response were significantly differentially expressed in complex seizures with influenza A(H1N1)pdm09, and transcripts related to the stress response were significantly differentially expressed in complex seizures with rotavirus gastroenteritis. Pathway analysis showed that the mitogen-activated protein kinases in the T cell receptor signaling pathway were activated in complex seizures due to influenza A(H1N1)pdm09. Dysregulation of the genes related to immune response or stress response could contribute to the pathogenic differences of the complex seizures due to influenza A(H1N1)pdm09 or rotavirus gastroenteritis.

Pathogenic mechanisms of influenza A(H1N1)pdm09 infection elucidated on gene expression profiling

The pathogenic mechanisms underlying influenza A(H1N1)pdm09‐associated central nervous system (CNS) manifestations and pneumonia remain unclear. This study examined A(H1N1)pdm09 host responses using gene expression profiles of patients’ peripheral blood.

Tumor necrosis factor-α can induce Langhans-type multinucleated giant cell formation derived from myeloid dendritic cells

The formation of the rich cellular features of MGCs, where the nuclei are arranged circularly at the periphery of the cell (morphologically epithelioid; Langhans‐type), is assumed to be associated with any granulomatous disease. The mechanism by which TNF controls the formation of human MGCs in vitro was investigated, focusing on the effect of the TNF‐neutralizing antibody.

Thalidomide prevents formation of multinucleated giant cells (Langhans-type cells) from cultured monocytes: possible pharmaceutical applications for granulomatous disorders.

Thalidomide is an effective drug for chronic inflammatory diseases, but the mechanism underlying its immunomodulatory action remains uncertain. Thalidomide has been reported to clinically improve chronic inflammatory granulomatous disorders. In such disorders, the granulomas consist of epithelioid cells, scattered lymphocytes and multinucleated giant cells (MNGC; Langhans-type cells). The present experimental approach permitted the reproduction of MNGC formation from peripheral blood monocytes and examination of thalidomides effect on it. MNGC can be effectively generated from monocytes cultured in the presence of interleukin-4 (IL-4) and macrophage colony-stimulating factor (M-CSF) for 14 days. Thalidomide can inhibit the formation of MNGC in a dose-dependent manner. MNGC formation was partly inhibited by the presence of neutralizing TNF-α antibody in the responses induced by IL-4 and M-CSF. Autocrinal TNF-α production and modulation of cadhelin expression to regulate cell adhesion might be involved in this inhibitory action of thalidomide. Our results support thalidomides clinical efficacy in the treatment of chronic granulomatous disorders (granulomatosis).

Late-onset Lymphedema and Protein-losing Enteropathy with Noonan Syndrome

Noonan syndrome is characterized by facial dysmorphology, congenital heart disease and growth failure. Although it is also accompanied by deranged lymph-vessel formation, protein-losing enteropathy (PLE) with Noonan syndrome is rarely reported. We report clinical information about a boy with Noonan syndrome and late-onset lymphedema and PLE after standing for long periods of time during athletic practice sessions. The boy recovered from lymphedema and PLE after administration of 2.5 g of albumin followed by resting and raising his legs. They did not recur after he began walking again. Standing for long periods of time congested the lymph stream at the abdominal lymph vessel, whose formation is frequently disturbed in Noonan syndrome, and the increased pressure caused lymphedema and PLE. PLE is one of the clinical manifestations of Noonan syndrome.

Local and Systemic Immune Responses to Influenza A Virus Infection in Pneumonia and Encephalitis Mouse Models

Objective To compare local and systemic profiles between different disease pathologies (pneumonia and encephalitis) induced by influenza A virus (IAV). Methods An IAV pneumonia model was created by intranasal inoculation of C57BL/6 mice with influenza A/WSN/33 (H1N1) virus. Lung lavage and blood collection were performed on day 3 after IAV inoculation. Similarly, an IAV encephalitis mouse model was created by direct intracranial IAV inoculation. Cerebrospinal fluid (CSF) and blood collection were conducted according to the same schedule. Cytokine/chemokine profiles were produced for each collected sample. Then the data were compared visually using radar charts. Results Serum cytokine profiles were similar in pneumonia and encephalitis models, but local responses between the bronchoalveolar lavage fluid (BALF) in the pneumonia model and CSF in the encephalitis model differed. Moreover, to varying degrees, the profiles of local cytokines/chemokines differed from those of serum in both the pneumonia and encephalitis models. Conclusion Investigating local samples such as BALF and CSF is important for evaluating local immune responses, providing insight into pathology at the primary loci of infection. Serum data alone might be insufficient to elucidate local immune responses and might not enable clinicians to devise the most appropriate treatment strategies.

Recurrent Chronic Cough, Wheeze and their Control without Corticosteroids in 1 to 5 Year-old Children

Background: Recurrent persistent cough and wheezing often begin in early childhood; however, not all episodes of them are caused by asthma and/or an allergic reaction, they are exacerbated with several respiratory infections. Previous research suggests that the best treatment for toddlers and preschool-age children with persistent cough and/or wheeze is a difficult clinical challenge. Methods: In this single-center prospective clinical trial, HIROSIMA study, we observed the clinical effect of oral leukotriene receptor antagonists (LTRAs: montelukast, pranlukast) with carbocystein and lysozyme chloride or ambroxol for over a year and assessed the relationship between infantile wheeze, chronic cough and rhinosinusitis. The patients were allocated to the intervention with their consent. Results: Eighty patients, who were admitted to hospital for persistent cough and dyspnea episodes, completed the study for a year and showed significantly fewer asthma exacerbation episodes (clinical asthma scores/week; 16.1 ± 3.1 vs 7.9 ± 2.7) during the first eight weeks (p < 0.01), comparing to the use of LTRA alone (n = 40).; and the improvement of conditions persisted for over the twelve-month period. None of the subjects was admitted to the hospital for asthma exacerbation, and had any corticosteroid treatment during the study. Conclusion: Our strategy for chronic cough including the management of allergic rhinitis and sinusitis significantly evaded persistent cough and wheeze of children age from 1 to 5 years, and reduced the frequency of recurrent otitis media. Note: HIROSIMA study provides promising data for the control of persistent cough and wheeze of children age from 1 to 5 years without the use of corticosteroids for over a year with a good adherence to the treatment.