Yasuyuki Nasuhara

Annual change in pulmonary function and clinical phenotype in chronic obstructive pulmonary disease.

RATIONALE Although the rate of annual decline in FEV1 is one of the most important outcome measures in chronic obstructive pulmonary disease (COPD), little is known about intersubject variability based on clinical phenotypes. OBJECTIVES To examine the intersubject variability in a 5-year observational cohort study, particularly focusing on emphysema severity. METHODS A total of 279 eligible patients with COPD (stages I-IV: 26, 45, 24, and 5%) participated. We conducted a detailed assessment of pulmonary function and computed tomography (CT) at baseline, and performed spirometry every 6 months before and after inhalation of bronchodilator. Smoking status, exacerbation, and pharmacotherapy were carefully monitored. Emphysema severity was evaluated by CT and annual measurements of carbon monoxide transfer coefficient. MEASUREMENTS AND MAIN RESULTS Using mixed effects model analysis, the annual decline in post-bronchodilator FEV1 was -32±24 (SD) ml/yr (n=261). We classified the subjects of less than the 25th percentile as Rapid decliners, the 25th to 75th percentile as Slow decliners, and greater than the 75th percentile as Sustainers (-63±2, -31±1, and -2±1 [SE] ml/yr). Emphysema severity, but not %FEV1, showed significant differences among the three groups. Multiple logistic regression analysis demonstrated that the Rapid decliners were independently associated with emphysema severity assessed either by CT or carbon monoxide transfer coefficient. The Sustainers displayed less emphysema and higher levels of circulating eosinophils. CONCLUSIONS Emphysema severity is independently associated with a rapid annual decline in FEV1 in COPD. Sustainers and Rapid decliners warrant specific attention in clinical practice.

Down-regulated NF-E2-related factor 2 in pulmonary macrophages of aged smokers and patients with chronic obstructive pulmonary disease.

Pulmonary macrophages are one of the sources of various antioxidant and detoxification enzymes for which NF-E2-related factor 2 (Nrf2) is a key transcriptional factor. Although Nrf2 deficiency reportedly induces severe emphysema in mice exposed to cigarette smoke (CS), no reports have studied Nrf2 regulation in chronic obstructive pulmonary disease (COPD). In this study, Nrf2 activation in response to CS was evaluated in human alveolar macrophages, and age-related differences in CS-induced Nrf2 regulation in mouse alveolar macrophages were determined. Furthermore, Nrf2 mRNA levels in human macrophages harvested by bronchoalveolar lavage or laser capture microdissection were measured. CS induced nuclear Nrf2 accumulation and up-regulation of Nrf2 target genes without substantial changes in Nrf2 mRNA levels in human alveolar macrophages. In humans, the Nrf2 mRNA level in lavaged macrophages of young subjects (n = 14) was independent of smoking status; however, the Nrf2 mRNA level was down-regulated in the lavaged macrophages of older current smokers (n = 14) compared with older nonsmokers (n = 9) (P < 0.001). Among older subjects, the macrophage Nrf2 mRNA level was inversely correlated with oxidized glutathione and carbonylated albumin levels in bronchoalveolar lavage fluid. In mice, aging suppressed the CS-induced up-regulation of Nrf2 target genes, as well as Nrf2, in alveolar macrophages. Furthermore, the Nrf2 mRNA level was decreased in laser capture microdissection-retrieved macrophages obtained from subjects with COPD (n = 10) compared with control subjects (n = 10) (P = 0.001). In conclusion, CS induces Nrf2 activation in macrophages, and Nrf2 expression is decreased in the macrophages of older current smokers and patients with COPD.

Characterisation of phenotypes based on severity of emphysema in chronic obstructive pulmonary disease

Background: Airflow limitation in chronic obstructive pulmonary disease (COPD) is caused by a mixture of small airway disease and emphysema, the relative contributions of which may vary among patients. Phenotypes of COPD classified purely based on severity of emphysema are not well defined and may be different from the classic phenotypes of “pink puffers” and “blue bloaters”. Methods: To characterise clinical phenotypes based on severity of emphysema, 274 subjects with COPD were recruited, excluding those with physician-diagnosed bronchial asthma. For all subjects a detailed interview of disease history and symptoms, quality of life (QOL) measurement, blood sampling, pulmonary function tests before and after inhalation of salbutamol (0.4 mg) and high-resolution CT scanning were performed. Results: Severity of emphysema visually evaluated varied widely even among subjects with the same stage of disease. No significant differences were noted among three groups of subjects classified by severity of emphysema in age, smoking history, chronic bronchitis symptoms, blood eosinophil count, serum IgE level or bronchodilator response. However, subjects with severe emphysema had significantly lower body mass index (BMI) and poorer QOL scores, evaluated using St George’s Respiratory Questionnaire (SGRQ), than those with no/mild emphysema (mean (SD) BMI 21.2 (0.5) vs 23.5 (0.3) kg/m2, respectively; SGRQ total score 40 (3) vs 28 (2), respectively; p<0.001 for both). These characteristics held true even if subjects with the same degree of airflow limitation were chosen. Conclusions: The severity of emphysema varies widely even in patients with the same stage of COPD, and chronic bronchitis symptoms are equally distributed irrespective of emphysema severity. Patients with the phenotype in which emphysema predominates have lower BMI and poorer health-related QOL.

Inhaled granulocyte/macrophage-colony stimulating factor as therapy for pulmonary alveolar proteinosis.

RATIONALE Inhaled granulocyte/macrophage-colony stimulating factor (GM-CSF) is a promising therapy for pulmonary alveolar proteinosis (PAP) but has not been adequately studied. OBJECTIVES To evaluate safety and efficacy of inhaled GM-CSF in patients with unremitting or progressive PAP. METHODS We conducted a national, multicenter, self-controlled, phase II trial at nine pulmonary centers throughout Japan. Patients who had lung biopsy or cytology findings diagnostic of PAP, an elevated serum GM-CSF antibody level, and a Pa(O(2)) of less than 75 mm Hg entered a 12-week observation period. Those who improved (i.e., alveolar-arterial oxygen difference [A-aDO(2)] decreased by 10 mm Hg) during observation were excluded. The rest entered sequential periods of high-dose therapy (250 microg Days 1-8, none Days 9-14; x six cycles; 12 wk); low-dose therapy (125 microg Days 1-4, none Days 5-14; x six cycles; 12 wk), and follow-up (52 wk). MEASUREMENTS AND MAIN RESULTS Fifty patients with PAP were enrolled in the study. During observation, nine improved and two withdrew; all of these were excluded. Of 35 patients completing the high- and low-dose therapy, 24 improved, resulting in an overall response rate of 62% (24/39; intention-to-treat analysis) and reduction in A-aDO(2) of 12.3 mm Hg (95% confidence interval, 8.4-16.2; n = 35, P < 0.001). No serious adverse events occurred, and serum GM-CSF autoantibody levels were unchanged. A treatment-emergent correlation occurred between A-aDO(2) and diffusing capacity of the lung, and high-resolution CT revealed improvement of ground-glass opacity. Twenty-nine of 35 patients remained stable without further therapy for 1 year. CONCLUSIONS Inhaled GM-CSF therapy is safe, effective, and provides a sustained therapeutic effect in autoimmune PAP. Clinical trial registered with www.controlled-trials.com/isrctn (ISRCTN18931678), www.jmacct.med.or.jp/english (JMA-IIA00013).

Effects of ageing and smoking on SP-A and SP-D levels in bronchoalveolar lavage fluid.

Surfactant protein (SP)-A and SP-D are collagen-like glycoproteins that are synthesised in the distal pulmonary epithelium. This study examined the effects of ageing and long-term smoking on SP-A and SP-D in the lungs. The possible links to the development of pulmonary emphysema were also investigated. Sequential lavage was performed in young and middle-aged or elderly nonsmokers and asymptomatic current smokers with various smoking histories. Middle-aged or elderly smokers were further categorised according to the presence of emphysema by high-resolution computed tomography. Levels of SP-A and SP-D in bronchial lavage (BL) fluid and in bronchoalveolar lavage (BAL) fluid were quantified by ELISA. Significant decreases in SP-A were seen with age in nonsmokers in BL fluid, but not in BAL fluid. Middle-aged or elderly smokers with emphysema had lower levels of SP-A in both BL and BAL fluids when compared with young subjects, and in BL fluid when compared with middle-aged or elderly smokers without emphysema. SP-D did not change with age alone, however, it was decreased in middle-aged or elderly smokers when compared with similarly aged nonsmokers. In conclusion, surfactant protein-A may decrease with age alone or due to the cumulative effects of long-term smoking and development of emphysema, while surfactant protein-D decreases due to long-term smoking.

Curcumin attenuates elastase- and cigarette smoke-induced pulmonary emphysema in mice

Curcumin, a yellow pigment obtained from turmeric (Curcumina longa), is a dietary polyphenol that has been reported to possess anti-inflammatory and antioxidant properties. The effect of curcumin against the development of pulmonary emphysema in animal models is unknown. The aim of this study was to determine whether curcumin is able to attenuate the development of pulmonary emphysema in mice. Nine-week-old male C57BL/6J mice were treated with intratracheal porcine pancreatic elastase (PPE) or exposed to mainstream cigarette smoke (CS) (60 min/day for 10 consecutive days or 5 days/wk for 12 wk) to induce pulmonary inflammation and emphysema. Curcumin (100 mg/kg) or vehicle was administrated daily by oral gavage 1 h and 24 h before intratracheal PPE treatment and daily thereafter throughout a 21-day period in PPE-exposed mice and 1 h before each CS exposure in CS-exposed mice. As a result, curcumin treatment significantly inhibited PPE-induced increase of neutrophils in bronchoalveolar lavage fluid at 6 h and on day 1 after PPE administration, with an increase in antioxidant gene expression at 6 h and significantly attenuated PPE-induced air space enlargement on day 21. It was also found that curcumin treatment significantly inhibited CS-induced increase of neutrophils and macrophages in bronchoalveolar lavage fluid after 10 consecutive days of CS exposure and significantly attenuated CS-induced air space enlargement after 12 wk of CS exposure. In conclusion, oral curcumin administration attenuated PPE- and CS-induced pulmonary inflammation and emphysema in mice.

Decreased Airway Expression of Vascular Endothelial Growth Factor in Cigarette Smoke-Induced Emphysema in Mice and COPD Patients

Vascular endothelial growth factor (VEGF) signaling is crucial for lung structure maintenance. Although VEGF deficiency plays a role in the pathogenesis of emphysema in animals, little is known about VEGF expression levels and functions, as well as VEGF receptors, in airway epithelial cells, which are in direct contact with the environment. In this study, C57BL/6J mice were exposed to cigarette smoke (CS) for short (∼ 10 days) and long (4–24 wk) time periods, and bronchiolar expressions of VEGF and its receptors VEGFR-1 and VEGFR-2 were examined. The relationships between the expressions of VEGF, VEGFR-1, and VEGFR-2 and smoking histories and/or chronic obstructive pulmonary disease (COPD) were examined in humans. The mRNA levels were quantified in bronchiolar epithelium harvested by laser capture microdissection in both mouse and human lung tissues or in human bronchial epithelium harvested by bronchoscopic brushing. The VEGF protein level was assessed by immunohistochemistry or enzyme-linked immunosorbent assay. Repeated CS exposure downregulated bronchiolar expressions of VEGF and both VEGF receptors at various time points prior to the development of emphysema. In humans, bronchiolar VEGF was significantly decreased in smokers with COPD compared to lifelong nonsmokers, as well as to smokers without COPD; however, there was no difference in bronchiolar VEGF levels between lifelong nonsmokers and smokers without COPD. On the other hand, bronchiolar VEGFR-2 was downregulated in smokers with and without COPD compared to lifelong nonsmokers. These findings suggest the association of downregulation of bronchiolar VEGF and its receptors with cigarette smoking and COPD.

Effect of low-dose theophylline on airway inflammation in COPD

Objective:  Recent studies have shown that theophylline may exert anti‐inflammatory effects on neutrophils. We undertook to assess the effect of theophylline on airway inflammation in COPD.

Long term smoking with age builds up excessive oxidative stress in bronchoalveolar lavage fluid

Background: Epithelial lining fluid plays a critical role in protecting the lung from oxidative stress, in which the oxidised status may change by ageing, smoking history, and pulmonary emphysema. Methods: Bronchoalveolar lavage (BAL) was performed on 109 young and older subjects with various smoking histories. The protein carbonyls, total and oxidised glutathione were examined in BAL fluid. Results: By Western blot analysis, the major carbonylated protein in the BAL fluid was sized at 68 kDa, corresponding to albumin. The amount of carbonylated albumin per mg total albumin in BAL fluid was four times higher in older current smokers and three times higher in older former smokers than in age matched non-smokers (p<0.0001, p = 0.0003, respectively), but not in young smokers. Total glutathione in BAL fluid was significantly increased both in young (p = 0.006) and older current smokers (p = 0.0003) compared with age matched non-smokers. In contrast, the ratio of oxidised to total glutathione was significantly raised (72%) only in older current smokers compared with the other groups. There was no significant difference in these parameters between older smokers with and without mild emphysema. Conclusions: Oxidised glutathione associated with excessive protein carbonylation accumulates in the lung of older smokers with long term smoking histories even in the absence of lung diseases, but they are not significantly enhanced in smokers with mild emphysema.

Relationship between improved airflow limitation and changes in airway calibre induced by inhaled anticholinergic agents in COPD

Background: Although airflow limitation improved by inhaled anticholinergic drugs varies among individuals with chronic obstructive pulmonary disease (COPD), the relationship between actual bronchodilation and improved pulmonary function and where in the lung such bronchodilation occurs remains unknown. A study was undertaken to determine the relationship between improved pulmonary function and changes in airway calibre at various sites in the airways in response to inhaled anticholinergic agents in patients with COPD using three-dimensional computed tomography (CT). Methods: CT scans were performed at deep inspiration and detailed pulmonary function tests before and 1 week after daily inhalations of tiotropium bromide in 15 patients with clinically stable COPD. The airway luminal area was examined at the third (segmental) to the sixth generations of eight bronchi in the right lung. Results: Bronchodilation was demonstrated by an overall average increase of 39% in the inner luminal area, and the mean (SE) forced expiratory volume in 1 s (FEV1) increased from 1.23 (0.11) l to 1.47 (0.13) l. The magnitude of bronchodilation was closely correlated with improved pulmonary function, particularly with that of FEV1 (r = 0.843, p<0.001). Such correlations were significant at the fourth to the sixth generation but not at the third generation of bronchi, and the slope of the regression lines became steeper from the third to the sixth generation. Conclusions: Inhaled anticholinergic agents induce overall bronchodilation which is in proportion to improvements in FEV1 in patients with COPD. Bronchodilation at the distal rather than the proximal airways is the determinant of functional improvement.