Depression is an important comorbidity of asthma. However, little information is available about depression and its potential impact on asthma control in Korean adult asthma patients. We aimed to estimate the prevalence and risk factors for depression in Korean adults with persistent asthma. The 127 non-elderly (20-64 yr) and 75 elderly (≥65 yr) patients with asthma were recruited. Demographic and clinical data were extracted, and the patients completed the Asthma Specific Quality of Life (AQOL) questionnaire and asthma control test (ACT). Depression status was defined using the Korean version of the Patient Health Questionnaire-9 (PHQ-9). Depression was more prevalent in non-elderly (18.9%) than in elderly patients with asthma (13.3%). Patients with depression were significantly younger, had lower economic status, shorter disease duration, poorer asthma control, and worse AQOL scores (P<0.05). Within the non-elderly group, younger age and shorter disease duration were significantly associated with depression (P<0.05). Within the elderly group, a higher body mass index and current smoking status were significantly associated with depression (P<0.05). The PHQ-9 score was significantly correlated with worse ACT and AQOL scores in both groups. In conclusion, depression is strongly associated with poor asthma control and quality of life in Korean adult asthma patients. Our results provide important clues that used to target modifiable factors which contribute to development of depression in asthma patients.
Adult Asthma; Asthma Control; Depression; Quality of Life
Glycogen storage disease type-Ia (GSD-Ia) patients deficient in glucose-6-phosphatase-α (G6Pase-α or G6PC) manifest impaired glucose homeostasis characterized by fasting hypoglycemia, growth retardation, hepatomegaly, nephromegaly, hyperlipidemia, hyperuricemia, and lactic acidemia. Two efficacious recombinant adeno-associated virus pseudotype 2/8 (rAAV8) vectors expressing human G6Pase-α have been independently developed. One is a single-stranded vector containing a 2864-bp of the G6PC promoter/enhancer (rAAV8-GPE) and the other is a double-stranded vector containing a shorter 382-bp minimal G6PC promoter/enhancer (rAAV8-miGPE). To identify the best construct, a direct comparison of the rAAV8-GPE and the rAAV8-miGPE vectors was initiated to determine the best vector to take forward into clinical trials. We show that the rAAV8-GPE vector directed significantly higher levels of hepatic G6Pase-α expression, achieved greater reduction in hepatic glycogen accumulation, and led to a better toleration of fasting in GSD-Ia mice than the rAAV8-miGPE vector. Our results indicated that additional control elements in the rAAV8-GPE vector outweigh the gains from the double-stranded rAAV8-miGPE transduction efficiency, and that the rAAV8-GPE vector is the current choice for clinical translation in human GSD-Ia.
glycogen storage disease type I; glucose-6-phosphatase; adeno-associated virus; gene therapy
Glycogen storage disease type Ia (GSD-Ia), characterized by impaired glucose homeostasis and chronic risk of hepatocellular adenoma (HCA), is caused by deficiencies in the endoplasmic reticulum (ER)-associated glucose-6-phosphatase-α (G6Pase-α or G6PC) that hydrolyzes glucose-6-phosphate (G6P) to glucose. G6Pase-α activity depends upon the G6P transporter (G6PT) that translocates G6P from the cytoplasm into the ER lumen. The functional coupling of G6Pase-α and G6PT maintains interprandial glucose homeostasis. We have previously shown that gene therapy mediated by AAV-GPE, an adeno-associated virus (AAV) vector expressing G6Pase-α directed by the human G6PC promoter/enhancer (GPE), completely normalizes hepatic G6Pase-α deficiency in GSD-Ia (G6pc−/−) mice for at least 24 weeks. However, a recent study showed that, within 78 weeks of gene deletion, all mice lacking G6Pase-α in the liver develop HCA. We now show that gene therapy mediated by AAV-GPE maintains efficacy for at least 70–90 weeks for mice expressing more than 3% of wild type hepatic G6Pase-α activity. The treated mice displayed normal hepatic fat storage, normal blood metabolite and glucose tolerance profiles, reduced fasting blood insulin levels, maintained normoglycemia over a 24-hour fast, and had no evidence of hepatic abnormalities. After a 24-hour fast, hepatic G6PT mRNA levels in G6pc−/− mice receiving gene therapy were markedly increased. Since G6PT transport is the rate-limiting step in microsomal G6P metabolism it may explain why the treated G6pc−/− mice could sustain prolonged fasts. The low fasting blood insulin levels and lack of hepatic steatosis may explain the absence of HCA.
These results confirm that AAV-GPE-mediated gene transfer corrects hepatic G6Pase-α deficiency in murine GSD-Ia and prevents chronic HCA formation.
Adeno-associated virus; glucose-6-phosphatase-α; glucose-6-phosphate transporter; blood insulin; glucose homeostasis
A canine model of Glycogen storage disease type Ia (GSDIa) is described. Affected dogs are homozygous for a previously described M121I mutation resulting in a deficiency of glucose-6-phosphatase-α. Metabolic, clinicopathologic, pathologic, and clinical manifestations of GSDIa observed in this model are described and compared to those observed in humans. The canine model shows more complete recapitulation of the clinical manifestations seen in humans including “lactic acidosis”, larger size, and longer lifespan compared to other animal models. Use of this model in preclinical trials of gene therapy is described and briefly compared to the murine model. Although the canine model offers a number of advantages for evaluating potential therapies for GSDIa, there are also some significant challenges involved in its use. Despite these challenges, the canine model of GSDIa should continue to provide valuable information about the potential for generating curative therapies for GSDIa as well as other genetic hepatic diseases.
Leukotriene receptor antagonists (LTRAs) are used to treat aspirin-intolerant asthma (AIA); however, the protective effects of long-term LTRA administration against aspirin-induced bronchospasm have not been evaluated.
We investigated the efficacy of a 12-week treatment with a LTRA in protecting against aspirin-induced asthma in AIA patients.
Fifty-two adult patients with AIA underwent an aspirin challenge test just before administration of montelukast (10 mg/day) and just after 12 weeks of treatment. The protective effect was assessed as the disappearance of aspirin-induced bronchospasm after 12 weeks of treatment. The results were compared according to the patients' clinical and physiological parameters.
The decline in FEV1 following aspirin challenge was significantly reduced from 28.6±1.9% to 10.2±1.7% (P=0.0001) after 12 weeks of montelukast treatment. However, 14 subjects (30%) still showed a positive response (>15% decline in FEV1) to aspirin challenge. Grouping the subjects into good and poor responders according to post-treatment responses revealed that the pretreatment aspirin-induced FEV1 decline was significantly greater in the poor responders and that the triggering dose of aspirin and the induction time for a positive response were lower and shorter, respectively, in the poor responders. Histories of aspirin hypersensitivity and sinusitis were more prevalent among the poor responders than among the good responders.
Twelve weeks of treatment with montelukast protected against aspirin-induced bronchospasm in 70% of the AIA cases. A poor response was associated with more severe aspirin-induced bronchospasms before treatment and a history of aspirin hypersensitivity or sinusitis.
A severe response to aspirin challenge may be a predictor of poor responsiveness to leukotriene antagonist treatment.
Asthma; leukotriene antagonists; aspirin; eosinophils
Rationale: Severe respiratory syncytial virus (RSV) bronchiolitis has been associated with deficient IFN-γ production in humans, but the role of this cytokine in determining the outcome of reinfection is unknown.
Objectives: To define the role of IFN-γ in the development of RSV-mediated airway hyperresponsiveness (AHR) and lung histopathology in mice.
Methods: Wild-type (WT) and IFN-γ knockout mice were infected with RSV in the newborn or weaning stages and reinfected 5 weeks later. Airway responses were assessed on Day 6 after the primary or secondary infection.
Measurements and Main Results: Both WT and IFN-γ knockout mice developed similar levels of AHR and airway inflammation after primary infection. After reinfection, IFN-γ knockout mice, but not WT mice, developed AHR, airway eosinophilia, and mucus hyperproduction. Intranasal administration of IFN-γ during primary infection but not during reinfection prevented the development of these altered airway responses on reinfection in IFN-γ knockout mice. Adoptive transfer of WT T cells into IFN-γ knockout mice before primary infection restored IFN-γ production in the lungs and prevented the development of altered airway responses on reinfection. Treatment of mice with IFN-γ during primary neonatal infection prevented the enhancement of AHR and the development of airway eosinophilia and mucus hyperproduction on reinfection.
Conclusions: IFN-γ production during primary RSV infection is critical to the development of protection against AHR and lung histopathology on reinfection. Provision of IFN-γ during primary infection in infancy may be a potential therapeutic approach to alter the course of RSV-mediated long-term sequelae.
respiratory syncytial virus; interferon-γ; asthma; airway hyperresponsiveness; mice
The mechanism and cause of acute eosinophilic pneumonia are largely unknown. Many factors including the smoking of cigarettes have been suggested, but none have been proven to directly cause acute eosinophilic pneumonia. The authors report a case of acute eosinophilic pneumonia in a young Asian male who recently started smoking. The diagnosis was made based on his clinical course and results of chest radiography, lung spirometry, bronchoalveolar lavage, and transbronchial lung biopsies. After administration of methylprednisolone, his clinical course rapidly improved. A provocation test was designed to establish a connection between cigarette smoking and the development of acute eosinophilic pneumonia. After the provocation test, the patient showed identical symptoms, increase in sputum eosinophils, and worsening of pulmonary function. The results of the provocation test suggest that smoking may directly cause acute eosinophilic pneumonia, and support previous reports of cigarette smoking-induced acute eosinophilic pneumonia.
Acute Eosinophilic Pneumonia; Smoking; Provocation Test
We report a case of hypersensitivity pneumonitis in a 30-yr-old female housewife caused by Penicillium species found in her home environment. The patient was diagnosed according to history, chest radiograph, spirometry, high-resolution chest CT, and transbronchial lung biopsy. To identify the causative agent, cultured aeromolds were collected by the open-plate method. From the main fungi cultured, fungal antigens were prepared, and immunoblot analysis with the patient's serum and each fungal antigen was performed. A fungal colonies were isolated from the patient's home. Immunoblotting analysis with the patient's sera demonstrated a IgG-binding fractions to Penicillium species extract, while binding was not noted with control subject. This study indicates that the patient had hypersensitivity pneumonitis on exposure to Penicillium species in her home environment.
Penicillium; Home Environment; Hypersensitivity Pneumonitis; Aleveolitis, Extrinsic Allergic
Glutathion S-transferase P1 (GSTP1), the abundant isoform of glutathione S-transferase in lung epithelium, plays an important role in cellular protection against oxidative stress and toxic foreign chemicals. GSTP1 (Ile105Val) polymorphism has been reported to be associated with asthma related phenotypes such as atopy and bronchial hyperresponsiveness. Therefore we investigated whether this polymorphism may be associated with the development of aspirin-intolerant asthma (AIA).
GSTP1 Ile105Val polymorphism was determined using a single based extension method in 88 AIA subjects and compared to 154 aspirin-tolerant asthma (ATA) subjects and 119 normal healthy controls (NC) recruited from the Korean population.
No significant differences in allele and genotype frequencies of the GSTP1 Ilel105Val polymorphism were observed in the three groups (p>0.05). However, minor G allele frequency of the GSTP1 Ilel105Val polymorphism in AIA group (16.5%) tended to be lower than in the NC group (20.6%).
These results suggest a lack of association of the GSTPI Ilel105Val gene polymorphism with AIA phenotype in the Korean population [word count: 159].
Aspirin-intolerant asthma; Hyperresponsiveness; Glutathione-S-transferase
This investigation was designed to confirm IL-8 production from human bronchial epithelial cells with toluene diisocyanate (TDI) exposure and to examine the effects of pro-inflammatory cytokine and dexamethasone. We cultured Beas-2B, a bronchial epithelial cell line with TDI-HSA conjugate and compared with those without conjugate. IL-8 in the supernatant was measured by ELISA. To evaluate the effect of proinflammatory cytokines, peripheral blood mononuclear cells (PBMC) were collected from TDI- and non-TDI asthma patients, and were added to the epithelial cell culture. Dexamethasone or antibodies to TNF-alpha and IL-1beta were pre-incubated with PBMC supernatant. There was a significant production of IL-8 from bronchial epithelial cells with addition of TDI-HSA conjugate in a dose-dependent manner, which was significantly augmented with addition of PBMC supernatant. Higher production of IL-8 was noted with addition of PBMC supernatant from TDI-asthma patients than in those from non-TDI asthma patients. IL-1beta and IL-1beta/TNF alpha antibodies were able to suppress the IL-8 productions. Pre-treatment of dexamethasone induced dose-dependent inhibition of the IL-8 production. These results suggest that the IL-8 production from bronchial epithelial cells contribute to neutrophil recruitment occurring in TDI-induced airway inflammation. IL-1beta released from PBMC of TDI-induced asthma patients may be one of the pro-inflammatory cytokines to enhance IL-8 production.
Eosinophil and mast cell infiltrations are consistent findings in nasal polyp tissue. Previous studies have shown that matrix metalloproteinases (MMPs) may be involved in eosinophil infiltration in airway mucosa of asthmatic patients, and that transforming growth factor-beta1 (TGF-beta1) induces extracellular matrix deposition in nasal polyp tissue. The aim of this study was to evaluate the role of MMPs and tissue-inhibitor of metalloproteinase-1 (TIMP-1) in association with TGF-beta1, eosinophils and mast cell activation in nasal polyp tissue. Nasal polyp tissues from 20 patients who underwent polypectomies were collected and prepared into tissue homogenate. Eosinophil cationic protein (ECP) and tryptase levels were measured by CAP system (Pharmacia, Sweden). MMP-2, MMP-9, TIMP-1 and TGF-beta1 levels were measured by enzyme-liked immunosorbent assay. MMP-2 was the predominant form of MMPs, followed by MMP-9 and TIMP-1. There were significant correlations between ECP, and MMP-9, MMP-2, TGF-beta1 and tryptase, but not with TIMP-1. Significant correlations were noted between tryptase, and MMP-2, MMP-9, and TGF-beta1, but not with TIMP-1. Close correlations were noted between TGF-beta1, and MMP-9 and MMP-2, but not with TIMP-1. MMP-2, MMP-9, and TGF-beta1 may contribute to eosinophil and mast cell migrations into nasal polyp tissue.
To investigate the pathogenic mechanism of late asthmatic response in comparison to early asthmatic response, changes of serum neutrophil chemotactic activity (NCA) using the Boyden chamber method and histamine level using the automated fluorometric analyzer were observed in 13 aspirin (ASA)-sensitive asthma subjects (group I: 7 early responders and group II: 6 dual responders) during lysine aspirin bronchoprovocation test (L-ASA BPT). Sera were collected before, and 30 min and 240 min after L-ASA BPT. Serum NCA increased significantly after 30 min (p=0.02) and decreased significantly at 240 min (p=0.02) in group I, while serum NCA of group II increased significantly at 30 min (p=0.04), tending to increase further up to 240 min with no statistical significance. NCA at 240 min in group II subjects was significantly higher than baseline NCA (p=0.02). The serum NCAs collected before and 240 min were significantly higher in group II than in group I (p<0.05, respectively). There were no significant changes in serum histamine levels during L-ASA BPT in both groups. NCA derived from mast cell may contribute to the development of early asthmatic response induced by L-ASA inhalation. There may be a possible involvement of NCA derived from mononuclear cells during late asthmatic response.
To confirm local production of IgE, and evaluate role of immunoglobulins on eosinophil activation in nasal polyp (NP) tissue, we measured IgG, IgA, secretory IgA(sIgA), total (tIgE) and specific IgE (sIgE) to Dermatophagoides pteronyssinus(DP) by ELISA in NP tissue homogenates from 51 subjects. They were classified according to skin reactivity to DP: group I, 15 highly atopic subjects; group II, 18 weakly atopic subjects; and group III, 18 non-atopic subjects. Eosinophil cationic protein (ECP) level was measured by CAP system. Highest level of DP-sIgE was noted in group I, followed by group II and III (p<0.05). Nine (60%) of group I and 4 (22%) of group II subjects had detectable level of DP-sIgE with no significant differences in IgA, sIgA, and IgG. All of NP tissue had eosinophilic infiltration with no significant difference in activated eosinophil count or ECP level among 3 groups. A significant correlation was noted between EG2+ cell count and tIgE (r=0.55, p<0.05), and DP-sIgE level (r=0.60, p<0.05). A significant correlation was also noted between ECP and IgG (r=0.51, p<0.05) and DP-sIgE level (r=0.47, p<0.05) with no significant correlation with IgA or sIgA. These results suggest that DP-sIgE was detectable in NP tissue from weakly atopic subjects as well as highly atopic subjects. IgG and sIgE may have potential roles in eosinophil degranulation in NP tissue.