Background: The comorbidity of asthma and allergic rhinitis is remarkably high, but not much is known about the effects of this combined condition on the quality of life. We aimed to evaluate the factors associated with asthma exacerbations and the effect of the exacerbations on the quality of life (QOL) through a one-year, large-scale, observational study in Japanese patients with asthma and rhinitis. Methods: A case survey by attending physicians and a patient survey was conducted at each assessment timepoint over a period of one year. Patients were divided into two groups according to the presence or absence of asthmatic attacks after enrollment and were matched using propensity scores to evaluate the factors associated with asthma exacerbations and the effect of the exacerbation on QOL. Results: Potential factors associated with asthma exacerbations included high body mass index value, low forced expiratory flow 75% of forced vital capacity (FEF75%), severe rhinitis as determined based on ARIA (Allergic Rhinitis and its Impact on Asthma). Although patients with asthma exacerbations had significantly impaired quality of life at baseline as evidenced by the economic aspects, in addition to physical, mental, and social activities, no further reduction with the attacks was observed. Conclusions: This study suggested that higher body mass index (BMI) and severe asthma as well as severe rhinitis were factors associated with asthma exacerbations. Although patients with asthma exacerbations had impaired QOL, attacks caused no further reduction. Copyright (C) 2019, Japanese Society of Allergology. Production and hosting by Elsevier B.V.

Active metabolites of vitamin A, retinoic acids (RAs), are known to play critical roles in mucosal immune responses and dramatically inhibit human eosinophil apoptosis, but the detailed mechanisms have not been elucidated. We previously screened for ICAM-1 (CD54) upregulation in RA-stimulated human eosinophils by gene microarray analysis. As ICAM-1 induction and activation were observed to have a role in maintenance of eosinophil survival, we tested the hypothesis that RAs prolong eosinophil survival through ICAM-1 outside-in signaling. Blood-derived isolated eosinophils cultured with 9-cis RA and all-trans RA showed significant upregulation of ICAM-1 mRNA and cell surface expression. TTNPB, a retinoic acid receptor agonist, also induced ICAM-1 expression, while HX630, a retinoid X receptor agonist, did not. Furthermore, an RAR antagonist, HX531, completely inhibited the effect of RAs. Upregulated ICAM-1 was associated with altered kinetics of Akt, ERK, and p38 MAP kinase phosphorylation through ICAM-1 cross-linking, but an ICAM-1-blocking antibody did not affect RA-mediated cell survival. These findings indicate that RAs induce functional ICAM-1 expression through RARs, but the induced ICAM-1 does not contribute to prolongation of eosinophil survival.

The comorbidity of asthma and allergic rhinitis is remarkably high, but not much is known about the effects of this combined condition on the quality of life (QOL). So we aimed to evaluate the predictors of asthma exacerbations and the effect of the exacerbations on QOL through a one-year, large-scale, observational study in Japanese patients with asthma and rhinitis. A case survey by attending physicians and a patient survey were conducted at each assessment timepoint, i.e. on the day of enrollment and at 1, 3, 6, 9, and 12 months after enrollment over a period of one year. Patients were divided into two groups according to the presence or absence of asthmatic attacks after enrollment and were matched using propensity scores to evaluate the predictors of asthma exacerbations and the effect of the exacerbation on QOL. Potential predictors of asthma exacerbations included high body mass index value, low forced expiratory flow 75% of forced vital capacity (FEF75%), severe rhinitis as determined based on ARIA (Allergic Rhinitis and its Impact on Asthma). Although patients with asthma exacerbations had significantly impaired QOL at baseline as evidenced by the economic aspects, in addition to physical, mental, and social activities, no further reduction with the attacks was observed. This study suggested that higher body mass index (BMI) and severe asthma as well as severe rhinitis were predictors of asthma exacerbations. Although patients with asthma exacerbations had impaired QOL, attacks caused no further reduction.

Estrogen influences the disease severity and sexual dimorphism in asthma, which is caused by complex mechanisms. Besides classical nuclear estrogen receptors (ERαβ), G-protein-coupled estrogen receptor (GPER) was recently established as an estrogen receptor on the cell membrane. Although GPER is associated with immunoregulatory functions of estrogen, the pathophysiological role of GPER in allergic inflammatory lung disease has not been examined. We investigated the effect of GPER-specific agonist G-1 in asthmatic mice. GPER expression in asthmatic lung was confirmed by immunofluorescent staining. OVA-sensitized BALB/c and C57BL/6 mice were treated with G-1 by daily subcutaneous injections during an airway challenge phase, followed by histological and biochemical examination. Strikingly, administration of G-1 attenuated airway hyperresponsiveness, accumulation of inflammatory cells, and levels of Th2 cytokines (IL-5 and IL-13) in BAL fluid. G-1 treatment also decreased serum levels of anti-OVA IgE antibodies. The frequency of splenic Foxp3+CD4+ regulatory T cells and IL-10-producing GPER+CD4+ T cells was significantly increased in G-1-treated mice. Additionally, splenocytes isolated from G-1-treated mice showed greater IL-10 production. G-1-induced amelioration of airway inflammation and IgE production were abolished in IL-10-deficient mice. Taken together, these results indicate that extended GPER activation negatively regulates the acute asthmatic condition by altering the IL-10-producing lymphocyte population. The current results have potential importance for understanding the mechanistic aspects of function of estrogen in allergic inflammatory response.

Sexual dimorphism in asthma links the estrogen and allergic immune responses. The function of estrogen was classically believed to be mediated through its nuclear receptors, i.e., estrogen receptors (ERs). However, recent studies established the important roles of G-protein-coupled estrogen receptor (GPER/GPR30) as a novel membrane receptor for estrogen. To date, the role of GPER in allergic inflammation is poorly understood. The purpose of this study was to examine whether GPER might affect the functions of eosinophils, which play an important role in the pathogenesis of asthma. Here, we demonstrated that GPER was expressed in purified human peripheral blood eosinophils both at the mRNA and protein levels. Although GPER agonist G-1 did not induce eosinophil chemotaxis or chemokinesis, preincubation with G-1 enhanced eotaxin (CCL11)-directed eosinophil chemotaxis. G-1 inhibited eosinophil spontaneous apoptosis and caspase-3 activities. The anti-apoptotic effect was not affected by the cAMP-phospodiesterase inhibitor rolipram or phosphoinositide 3-kinase inhibitors. In contrast to resting eosinophils, G-1 induced apoptosis and increased caspase-3 activities when eosinophils were co-stimulated with IL-5. No effect of G-1 was observed on eosinophil degranulation in terms of release of eosinophil-derived neurotoxin (EDN). The current study indicates the functional capacities of GPER on human eosinophils and also provides the previously unrecognized mechanisms of interaction between estrogen and allergic inflammation.

Background: Asthma is characterized by chronic inflammation caused by activation of immune cells including Th2 lymphocytes and eosinophils. Phosphoinositide 3-kinase (PI3K) gamma deficient asthmatic mice did not develop lung eosinophilia, although the detailed mechanisms are not well known. A CC chemokine eotaxin (CCL11) plays a prominent role in developing eosinophilic inflammation through CCR3. In this study, we tested the roles of PI3K gamma in eotaxin-induced eosinophil functions using a pharmacological inhibitor.Method: Human peripheral blood eosinophils were isolated by CD16-negative selection method. The effect of AS605240, synthetic PI3K gamma inhibitor on eotaxin-induced adhesion, chemotaxis, and degranulation were studied using intracellular adhesion molecule-1 (ICAM-1)-coated plates, Boyden chamber system, ELISA for eosinophil-derived neurotoxin (EDN) levels in the culture supernatant, respectively. CCR3 expression levels and extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation were assessed by flowcytometry. Involvement of PI3K gamma in spontaneous apoptosis was studied using flowcytometry.Results: Although AS605240 did not affect the eosinophil spontaneous apoptosis, eotaxin-induced chemotaxis, adhesion to ICAM-1 coated plate, and EDN release were inhibited by AS605240. AS605240 also inhibited the eotaxin-induced ERK1/2 phosphorylation without down-regulation of surface CCR3 expression.Conclusion: These results indicate that PI3K gamma inhibitor attenuates eotaxin-induced eosinophil functions by suppressing the downstream signaling of CCR3 without significant cytotoxicity. PI3K gamma plays an important role in the development of eosinophilic inflammation and blockade of PI3K gamma might be a therapeutic strategy for treatment of eosinophil-related diseases including asthma. Crown Copyright (C) 2013 Published by Elsevier Ltd. All rights reserved.

Background and objective Epidemiological studies have shown that the prevalence of adult asthma and severe asthma is higher in women. It has also been reported that female mice are more susceptible than males to the development of allergic airway inflammation and airway hyperresponsiveness (AHR). The influence of gender difference in the pathogenesis of severe asthma, especially airway remodelling in an animal model, has been studied rarely. We investigated gender difference in the development of airway remodelling using a long-term antigen-challenged mouse asthma model. Methods Following ovalbumin (OVA)/alum intraperitoneal injection, male or female mice (BALB/c) were challenged with aerosolized 1% OVA on 3 days/week for 5 weeks, and differences in AHR, airway inflammation and airway remodelling between the sexes were investigated. Results In OVA-sensitized and OVA-challenged (OVA/OVA) female mice, eosinophils, lymphocytes, T-helper type 2 cytokines and growth factors in bronchoalveolar lavage fluid were increased compared with OVA/OVA male mice. Histological features of airway remodelling were also increased in OVA/OVA female mice. Serum total and OVA-specific immunoglobulin E (IgE) and serum IgA were significantly elevated in OVA/OVA female mice. Conclusions These results indicate that female mice experience more airway remodelling compared with male mice. These results suggest the involvement of sex hormones and gender differences in cellular functions in airway remodelling.

Objective: Growing evidence has shown an association between obesity and asthma. Adiponectin, an adipocyte-derived cytokine, is known to have anti-inflammatory effects with reduced concentrations in obese subjects. Recent findings raised the intriguing possibility that adiponectin might play a role in allergic inflammation, although the mechanistic basis for their relationship remains unclear. The purpose of this study was to examine whether adiponectin might affect functions of eosinophils, which play an important role in the pathogenesis of asthma. Methods: Human peripheral blood eosinophils were purified to study expression of adiponectin receptors AdipoR1 and AdipoR2 using RT-PCR and flow cytometry. The effect of adiponectin on eosinophil survival was investigated using annexin V and propidium iodide staining. Eotaxin-induced cell adhesion was investigated using ICAM-1-coated plates. A Boyden chamber and real-time horizontal migration system were used for eotaxin-directed chemotaxis assay. Expression of eotaxin receptor CCR3 and intracellular calcium influx were assessed by flow cytometry. Results: AdipoR1 and AdipoR2 were expressed in human eosinophils. Adiponectin did not affect eosinophil survival or CCR3 expression; however, eotaxin-enhanced adhesion was inhibited by pretreatment with adiponectin. Adiponectin also diminished eotaxin-directed chemotactic responses by disturbing both velocity and directionality. Calcium influx in response to eotaxin was attenuated by adiponectin. Conclusions: These results indicate that adiponectin attenuates the eosinophil functions induced by eotaxin without affecting cell viability. The inhibitory effect was associated with diminished calcium signaling rather than altering of surface receptor expression. Increasing circulating adiponectin might be a novel therapeutic modality for treatment of asthma, especially in obese asthmatics.

Pulmonary metastasis from leiomyosarcoma is rare and its clinical management is challenging. A single lung metastasis from a perineal leiomyosarcoma occurred in a 79-year-old woman. Five months after resection of the lung metastasis, a new metastatic tumor developed in the contralateral lung. Since the patient did not desire to receive hospitalized treatment, TS-1 (an oral agent consisting of a combination of tegafur, gimeracil, and oteracil potassium) therapy was started on an outpatient basis. The lung metastasis has been successfully controlled for at least 17 months with excellent tolerability. The clinical features and the treatment of this case are discussed.

Eotaxins and their receptor CCR 3 have a definitive role for tissue accumulation of eosinophils both under homeostatic and pathologic conditions. However, physiological stimuli that can up‐regulate CCR 3 in blood‐derived human eosinophils have not been recognized. As a prior gene microarray study revealed up‐regulation of CCR 3 in eosinophils stimulated with retinoic acids ( RA s), the expression of functional CCR 3 was examined. We found that 9‐cis RA and all‐trans RA ( ATRA ) significantly induced surface CCR 3 expression regardless of the presence of IL ‐3 or IL ‐5. Pharmacological manipulations with receptor‐specific agonists and antagonists indicated that retinoic acid receptor‐α activation is critical for CCR 3 up‐regulation. RA ‐induced CCR 3 was associated with its functional capacity, in terms of the calcium mobilization and chemotactic response to eotaxin‐1 ( CCL 11). Our study suggests an important role of vitamin A derivatives in the tissue accumulation of eosinophils.

The dioxins and dioxin-like compounds in cigarette smoke and environmental pollutants modulate immunological responses. These environmental toxicants are known to cause lung cancer but have also recently been implicated in allergic and inflammatory diseases such as bronchitis, asthma, and chronic obstructive pulmonary disease (COPD). In a novel pathway of this response, the activation of a nuclear receptor, arylhydrocarbon receptor (AhR), mediates the effects of these toxins through the arachidonic acid cascade, cell differentiation, cell-cell adhesion interactions, cytokine expression, and mucin production that are implicated in the pathogenesis and exacerbation of asthma/COPD. We have previously reported that human bronchial epithelial cells express AhR, and AhR activation induces mucin production through reactive oxygen species. This review discusses the role of AhR in asthma and COPD, focusing in particular on inflammatory and resident cells in the lung. We describe the important impact that AhR activation may have on the inflammation phase in the pathology of asthma and COPD. In addition, crosstalk of AhR signaling with other ligand-activated transcription factors such as peroxisome proliferator-activated receptors (PPARs) has been well documented.

It has been pointed out that obesity is a risk factor for, and is involved in the exacerbation of asthma. Mounting evidence about adipose tissue-derived proteins (adipokines) gave rise to the current understanding of obesity as a systemic inflammatory disorder. In this review, we summarized the involvement of leptin, focusing on eosinophil functions. Several studies have indicated that leptin can restrain eosinophil apoptosis, enhance migration, increase adhesion molecules and induce cytokine production. Since leptin also acts on a variety of immune cells related to allergic response, increased leptin in obese individuals potentially explains the mechanism by which obesity leads to an exacerbation of asthma. Further studies targeting adipokines will delineate the association between obesity and eosinophil-associated diseases.

Background Epidemiological studies have already shown that females are dominant in terms of the sex ratio of adult asthma prevalence and severe asthma. It has also been reported that female mice are more susceptible to the development of allergic airway inflammation and airway hyperresponsiveness (AHR) than males. However, there have been few reports of studies on sex difference in the pathogenesis of severe asthma, especially airway remodeling in an animal model. In this study, we investigated sex difference in formation of airway remodeling using a long-term antigen challenged asthma model. Methods Following ovalbumin (OVA)/alum intraperitoneal injection, male or female mice (BALB/c) were challenged with aerosolized 1% OVA on 3 days/week for 5 weeks, and we investigated the sex difference in AHR, airway inflammation, as well as airway remodeling. Results In OVA-sensitized and -challenged (OVA/OVA) female mice, AHR, the number of eosinophils and lymphocytes, as well as Th2 cytokines and growth factors in BAL fluid were increased compared with OVA/OVA male mice. On the other hand, there is no significant difference in the level of eotaxin in BAL fluid. The histological features of airway remodeling, including goblet cell hyperplasia, subepithelial fibrosis and myofibroblast hypertrophy, were also increased in OVA/OVA female mice. Moreover, serum total and OVA-specific IgE were significantly elevated in OVA/OVA female mice. Conclusions These results indicate that female mice are dominant in terms of forming airway remodeling as compared with male mice. The involvement of sex difference for sensitization and growth factor release in lung tissue based on inflammatory cell infiltration is indicated for the mechanism of sex difference of airway remodeling.

Background: Despite the fact that previous studies have indicated the significant roles of polyunsaturated fatty acids (PUFAs) in the immune system through peroxisome proliferator-activated receptor alpha (PPARα) and PPARγ, the biological functions and the mechanisms of action in eosinophils are poorly understood. Methods: We investigated the functional effects of docosahexaenoic acid (DHA, n-3 PUFA) on human peripheral blood eosinophils, using in vitro systems to test the hypothesis that DHA negatively regulates eosinophil mechanisms through PPARα and PPARγ. Results: Eosinophil apoptosis that spontaneously occurs under normal culture conditions was accelerated in the presence of DHA. In addition, eotaxin-directed eosinophil chemotactic responses were inhibited by pretreatment with DHA, disturbing both the velocity and the directionality of the cell movement. Pharmacological manipulations with specific antagonists indicated that the effects of DHA were not mediated through PPARα and PPARγ, despite the presence of these nuclear receptors. DHA also induced Fas receptor expression and caspase-3 activation that appears to be associated with a proapoptotic effect of DHA. Further, DHA rapidly inhibited the expression of eotaxin receptor C-C chemokine receptor 3 and eotaxin-induced calcium influx and phosphorylation of extracellular signal-regulated kinase. Interestingly, these inhibitory effects were not observed with linoleic acid (n-6 PUFA). Conclusions: The data might explain one of the mechanisms found in previous research showing the favorable effects of n-3 PUFA supplementation on allergic diseases, and provide novel therapeutic strategies to treat eosinophilic disorders.