Myocarditis mimicking acute coronary syndrome following influenza B virus infection: a case report

We present a notable case of a 15-year-old male infected with influenza B virus who showed the clinical manifestations of myocardial ischemia. He was admitted to our hospital with sudden chest pain. He had febrile illness for the past 2 days. Rapid antigen test for influenza revealed positive influenza B virus antigen. The initial electrocardiogram showed elevation of the ST-segments in leads II, II, aVF and reciprocal depression in leads V1 and V2. Serum test showed elevation of creatine kinase and troponin T. Gadlinium-enchanced magnetic resonance imaging, Tl-201 and I-123 beta-methyl-p-iodephenyl-pentadecanoic acid scintigram, coronary angiography revealed no abnormality. Follow-up electrocardiogram showed ST-segment change improvement over the course. Myocarditis associated with influenza B virus seemed to be caused by endothelial impairment and disturbance of microcirculation rather than direct injury to cardiac myocytes

Anti-fibrotic Effects of ONO-EF-345, a Specific Phosphodiesterase IV inhibitor, on Lung Fibroblasts

Phosphodiesterase (PDE) IV inhibitors have been shown to inhibit various inflammatory reactions in pulmonary diseases such as bronchial asthma and chronic obstructive lung diseases (COPD). However, there have been no studies evaluating the effect of PDE IV inhibitors on airway fibrosis, which is a critical feature of airway remodeling in asthma and COPD. We therefore examined whether ONO-EF-345 (ONO), a PDE IV inhibitor, affected the function of lung fibroblasts. ONO suppressed TGF-ß-induced type I collagen (COL1) mRNA expression in lung fibroblasts and also inhibited TGF-ß-induced a- smooth muscle actin (SMA) protein expression. ONO did not affect Smad2 phosphorylation or Smad7 expression. However, ONO reduced JNK and p38 activation, which regulates TGF-ß-induced COL1 expression. These results indicate that PDE IV inhibitors exert anti-fibrotic effects through the JNK and/or p38 pathways

IL-10 Inhibits Transforming Growth Factor-ß-Induction of Type I Collagen mRNA Expression via Both JNK and p38 Pathways in Human Lung Fibroblasts

Transforming growth factor-ß (TGF-ß) is a key factor for understanding the pathogenesis of fibrotic disorders such as idiopathic pulmonary fibrosis (IPF). We have demonstrated that interleukin-10 (IL-10) suppresses TGF-ß-induced expression of type I collagen (COL1) mRNA in a human lung fibroblast cell line (WI-38). However, the inhibitory mechanism has not yet been clearly elucidated. Thus, in the current study, we investigate the effects of IL-10 blockade of TGF-ß signaling which regulates COL1 mRNA expression. In WI-38 cells, IL-10 inhibits TGF-ß-mediated phosphorylation of both, c-Jun HN2-terminal kinase (JNK) and p38, but does not suppress TGF-ß- mediated phosphorylation of Smad2 or affect TGF-ß-upregulation of Smad7 mRNA expression. In addition, SP600125 and SB203580, specific inhibitors of JNK and p38, respectively, attenuate TGF-ß-induced COL1 mRNA expression in WI-38 cells. These results suggest that IL-10 inhibits TGF-ß-induced COL1 mRNA expression via both JNK and p38 pathways but not Smad pathways in WI-38 cells. This inhibitory mechanism may provide a novel insight into therapeutic strategies for fibrotic disorders such as IPF

Serum Biomarkers in a Radiological Pattern of Non-Fibrotic Hypersensitivity Pneumonitis: Implications for Mechanistic Difference and Differential Diagnosis

Hypersensitivity pneumonitis (HP) is a consequence of immune-mediated reactions caused by recurrent exposure to environmental agents. Recently, clinical practice guidelines for the diagnosis of HP were published and increased interest in HP. On the other hand, novel therapies have recently emerged for various diseases, and the management of drug-related pneumonitis (DRP) has become increasingly important. Among DRP, the HP pattern (DRP-HP) shows small, poorly defined centrilobular nodules with or without widespread areas of ground-glass opacity or lobular areas of decreased attenuation and vascularity. A similar radiological pattern of non-fibrotic HP can be induced, irrespective of inhalation (non-fibrotic HP) or intravenous administration (DRP-HP). However, their difference has not been well described, although the distribution of lesions in the lungs was slightly different between these two conditions. In this review, we focus on serum biomarkers of lung epithelial cells in order to investigate the difference between DRP-HP and non-fibrotic HP (common-HP). Serum levels of Krebs von den Lungen 6 (KL-6) might be relatively lower (occasionally normal) in DRP-HP than in common-HP, implying a mechanistic difference. KL-6 could be useful in discriminating between DRP and non-fibrotic HP (common type)