Kojiro Hirano

Tiotropium bromide inhibits TGF-β-induced MMP production from lung fibroblasts by interfering with Smad and MAPK pathways in vitro.

Background: Chronic obstructive pulmonary disease (COPD) is characterized by chronic inflammation and structural alterations (ie, tissue remodeling) throughout the conducting airways, parenchyma, and pulmonary vasculature. Matrix metalloproteinases (MMPs) are extracellular degrading enzymes that play a critical role in inflammatory cell infiltration and tissue remodeling, but the influence of the agents that are used for the treatment of COPD on the production of MMPs is not well understood. Purpose: The present study aimed to examine the influence of tiotropium bromide hydrate (TBH) on the production of MMPs from lung fibroblasts (LFs) induced by transforming growth factor (TGF)-β in vitro. Methods: LFs, at a concentration of 5 × 105 cells·mL−1, were stimulated with TGF-β in the presence of various concentrations of TBH. MMP-1 and MMP-2 levels in culture supernatants were examined by enzyme-linked immunosorbent assay (ELISA), and MMP messenger ribonucleic acid (mRNA) expression was examined by real-time polymerase chain reaction (RT-PCR). The influence of TBH on TGF-β signaling pathways was also analyzed by examining Smad activation and signaling protein phosphorylation by ELISA. Results: TBH at more than 15 pg·mL−1 inhibited the production of MMP-1 and MMP-2, but not tissue inhibitor of matrix metalloproteinase (TIMP)-1 and TIMP-2, from LFs, after TGF-β stimulation. TBH also suppressed MMP mRNA expression through the inhibition of Smad activation and signaling protein, extracellular-signal-regulated kinase (ERK) 1 and 2, and c-Jun N-terminal kinase (JNK), phosphorylation. Conclusion: These results may suggest that TBH suppresses MMP production from LFs, through interference of TGF-β-mediated signaling pathways and results in favorable modification of the clinical status of COPD.

Effect of histamine H1 receptor antagonists on TARC/CCL17 and MDC/CCL22 production from CD14+ cells induced by antigenic stimulation in vitro.

Background: Thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) are accepted to be important molecules in the development and maintenance of allergic diseases. Although several types of histamine H1 receptor antagonist (antihistamine) have been developed and used for the treatment of allergic diseases, the influence of antihistamines on TARC and MDC production is not well understood. Objective: The present study was undertaken to examine the influence of antihistamines on TARC and MDC production from CD14+ cells after antigenic stimulation in vitro. Methods: CD14+ cells prepared from patients with pollinosis to Japanese cedar pollen were stimulated with specific allergen extracted from Japanese cedar pollen (Cry j 1) in the presence of azelastine (AZE), ketotifen (KET), fexofenadine (FEX) and oxatomide (OXA) for 6 days. TARC and MDC levels in culture supernatants were examined by ELISA. We also examined the influence of FEX on TARC and MDC mRNA expression, phosphorylation of mitogen-activated protein kinases (MAPKs) and transcription factor activation in CD14+ cells after Cry j 1 stimulation. Results: FEX at 250 ng/ml, which is almost equal to therapeutic blood levels, caused a significant inhibition of TARC and MDC production.However, AZE, OXA and KET required higher concentrations than their therapeutic blood levels to suppress production of these factors. FEX at 250 ng/ml also suppressed NF-ĸB activation, phosphorylation of p38 MAPK and extracellular signal-regulated kinases 1 and 2 and expression of mRNA for TARC and MDC. Conclusions: These results suggest that antihistamines, especially FEX, suppress CC chemokine production from CD14+ cells through interference with antigen-mediated signaling and result in favorable modification of allergic disease states or conditions.

Suppression of nitric oxide production from nasal fibroblasts by metabolized clarithromycin in vitro

BackgroundLow-dose and long-term administration of 14-membered macrolide antibiotics, so called macrolide therapy, has been reported to favorably modify the clinical conditions of chronic airway diseases. Since there is growing evidence that macrolide antibiotic-resistant bacterias spreaders in the populations received macrolide therapy, it is strongly desired to develop macrolide antibiotics, which showed only anti-inflammatory action. The present study was designed to examine the influence of clarithromycin (CAM) and its metabolized materials, M-1, M-4 and M-5, on free radical generation from nasal polyp fibroblasts (NPFs) through the choice of nitric oxide (NO), which is one of important effector molecule in the development of airway inflammatory disease in vitro.MethodsNPFs (5 × 105 cells/ml) were stimulated with 1.0 μg/ml lipopolysaccharide (LPS) in the presence of agents for 24 hours. NO levels in culture supernatants were examined by the Griess method. We also examined the influence of agents on the phosphorylation of MAPKs, NF-κB activation, iNOS mRNA expression and iNOS production in NPFs cultured for 2, 4, 8, and 12 hours, respectively.ResultsThe addition of CAM (> 0.4 μg/ml) and M-4 (> 0.04 μg/ml) could suppress NO production from NPFs after LPS stimulation through the suppression of iNOS mRNA expression and NF-κB activation. CAM and M-4 also suppressed phosphorylation of MAPKs, ERK and p38 MAPK, but not JNK, which are increased LPS stimulation. On the other hand, M-1 and M-5 could not inhibit the NO generation, even when 0.1 μg/ml of the agent was added to cell cultures.ConclusionThe present results may suggest that M-4 will be a good candidate for the agent in the treatment of chronic airway inflammatory diseases, since M-4 did not have antimicribiological effects on gram positive and negative bacteria.

Successful treatment of eosinophilic otitis media associated with severe bronchial asthma with an anti-IL-5 monoclonal antibody, mepolizumab

Eosinophilic otitis media (EOM), which is characterized by the accumulation of eosinophils in middle ear effusion and the middle ear mucosa, is a refractory type of otitis media that is often associated with asthma. Although an early diagnosis and appropriate treatment are necessary to prevent the progression of hearing loss in patients with EOM, there are currently no well-established treatments for this condition. We treated a 60-year-old male patient with asthma and EOM. The patients asthma was poorly controlled, despite the use of high-dose inhaled corticosteroids, long-acting beta-agonist treatment, and the regular use of systemic corticosteroids. Mepolizumab, an anti-IL-5 monoclonal antibody, was started to treat the patients refractory asthma. At 4 months after the initiation of mepolizumab treatment, the patients asthma, hearing, and middle ear effusion improved. The present case suggests that mepolizumab therapy can control EOM and asthma.

Suppression of osteopontin functions by levocetirizine, a histamine H1 receptor antagonist, in vitro.

Objectives. Osteopontin (OPN), a multifunctional glycoprotein secreted from a wide variety of cells after inflammatory stimulation, is well accepted to contribute to the development of allergic diseases. However, the influence of histamine H1 receptor antagonists (antihistamines) on OPN functions is not well understood. The present study was undertaken to examine the influence of antihistamines on OPN functions in vitro. Methods. Human nasal epithelial cells (5 × 105 cells) were stimulated with 250 ng/mL OPN in the presence of either desloratadine (DL), fexofenadine (FEX), or levocetirizine (LCT). The levels of OPN, GM-CSF, Eotaxin, and RANTES in 24 h culture supernatants were examined by ELISA. The influence of LCT on mRNA expression and transcription factor activation in cells were also examined by real-time RT-PCR and ELISA, respectively. Key Findings. The antihistamines examined significantly suppressed the production of GM-CSF, Eotaxin, and RANTES from cells after OPN stimulation. LCT also exhibited the suppression of mRNA expression for chemokines and transcription factor, NF-κB and AP-1, activation, which were increased by the stimulation of cells with OPN. Conclusions. The suppressive activity of LCT on OPN functions on nasal epithelial cells may be responsible for the attenuating effect of the agent on allergic diseases.