A Randomized, Placebo-controlled Trial of Roflumilast. Effect on Proline-Glycine-Proline and Neutrophilic Inflammation in Chronic Obstructive Pulmonary Disease.

RATIONALE: Roflumilast is a therapeutic agent in the treatment of chronic obstructive pulmonary disease (COPD). It has antiinflammatory effects; however, it is not known whether it can affect a biologic pathway implicated in COPD pathogenesis and progression. The self-propagating acetyl-proline-glycine-proline (AcPGP) pathway is a novel means of neutrophilic inflammation that is pathologic in the development of COPD. AcPGP is produced by extracellular matrix collagen breakdown with prolyl endopeptidase and leukotriene A4 hydrolase serving as the enzymes responsible for its production and degradation, respectively. OBJECTIVES: We hypothesized that roflumilast would decrease AcPGP, halting the feed-forward cycle of inflammation. METHODS: We conducted a single-center, placebo-controlled, randomized study investigating 12 weeks of roflumilast treatment added to current therapy in moderate-to-severe COPD with chronic bronchitis. Subjects underwent sputum and blood analyses, pulmonary function testing, exercise tolerance, and quality-of-life assessment at 0, 4, and 12 weeks. MEASUREMENTS AND MAIN RESULTS: Twenty-seven patients were enrolled in the intention-to-treat analysis. Roflumilast treatment decreased sputum AcPGP by more than 50% (P < 0.01) and prolyl endopeptidase by 46% (P = 0.02), without significant improvement in leukotriene A4 hydrolase activity compared with placebo. Roflumilast also reduces other inflammatory markers. There were no significant changes in lung function, quality of life, or exercise tolerance between roflumilast- and placebo-treated groups. CONCLUSIONS: Roflumilast reduces pulmonary inflammation through decreasing prolyl endopeptidase activity and AcPGP. As expected for lower AcPGP levels, markers of neutrophilic inflammation are blunted. Inhibiting this self-propagating pathway lessens the overall inflammatory burden, which may alter the natural history of COPD, including the risk of exacerbation. Clinical trial registered with www.clinicaltrials.gov (NCT 01572948).

Significance of serum peptidylarginine deiminase type 4 in ANCA-associated vasculitis.

OBJECTIVE: To investigate the clinical significance of peptidylarginine deiminase type 4 (PAD4) in the pathogenesis of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). To make a primary observation on the relationship of chronic bronchitis and bronchiectasis (CB) with the pathogenesis of AAV by PAD4. METHODS: The sera from 13 patients with AAV, 13 patients with CB, 11 patients with rheumatoid arthritis (RA), 11 patients with primary chronic kidney disease (CKD) and 12 normal controls were collected. Serum PAD4 was detected using commercial ELISA kits. The serum levels of PAD4 were compared not only among the different groups but also between the activity and remission stage of the same disease. The associations between serum PAD4 and the Birmingham Vasculitis Activity Score (BVAS) of AAV were further investigated. RESULTS: (1) The serum levels of PAD4 in patients with AAV, RA and CB at activity stage were all higher than that in the normal controls (P<0.001, respectively, α'=0.007). The serum level of PAD4 in patients with CB at remission stage and that in CKD group were not found elevated compared with the normal controls (P=0.02, P=0.085, respectively, α'=0.007). (2) At activity stage, among the groups of simple AAV, AAV with a long history of CB and CB without AAV, no significant difference was detected. While at remission stage among the 3 groups, the serum level of PAD4 was at the lowest level in CB group without AAV. (3) The serum level of PAD4 in some patients with CB without AAV were found still higher at remission stage. (4) The serum level of PAD4 in AAV with renal damage at activity stage was positively correlated with BVAS (the activity score of AAV, r=0.71, P=0.02). CONCLUSION: PAD4 is involved in the pathogenesis of AAV. Whether some patients with CB might progress to AAV by the link with PAD4 still need further investigation.

Implication of dipeptidylpeptidase IV activity in human bronchial inflammation and in bronchoconstriction evaluated in anesthetized rabbits.

BACKGROUND: Decreased dipeptidylpeptidase IV (DPPIV) activity within the human nasal mucosa has previously been shown to contribute to the severity of chronic inflammatory rhinosinusitis. OBJECTIVE: To investigate and correlate the role of DPPIV activity with regard to bronchial inflammation. METHODS: DPPIV/CD26 activity/concentration was investigated in the bronchial tissue of human subjects suffering from chronic bronchial inflammation. In addition, the effect of a recombinant Aspergillus fumigatus DPPIV (fuDPPIV) was investigated on histamine-induced bronchoconstriction in anesthetized rabbits. RESULTS AND CONCLUSIONS: DPPIV/CD26 was present in submucosal seromucous glands, in leukocytes and to a very low degree in endothelial cells of human bronchi. DPPIV activity was correlated with tissue CD26 content measured by immunoassay. As previously reported for the nasal mucosa, DPPIV/CD26 activity was inversely correlated with the degree of airway inflammation. Systemic pretreatment with recombinant fuDPPIV markedly reduced the increase in histamine-induced airway resistance in rabbits. In conclusion, DPPIV activity modulates lower airway tone by degrading unknown peptidic substrates released by histamine in response to an allergen. Contrasting with our observations in the nose, this modulation is apparently not mediated via a neurokinin (NK1) receptor.

[Vapor condensate of exhaled air in evaluating the impaired metabolism of the bronchopulmanory system in nonspecific lung diseases]. / Kondensat parov vydykhaemogo vozdukha v otsenke stepeni narusheniia metabolizma bronkholegochnoi sistemy pri nespetsificheskikh zabolevaniiakh legkikh.

The degree of metabolic rehabilitation of the bronchopulmonary system was evaluated in non-specific pulmonary diseases, like pneumonia or chronic obstructive bronchitis, by using the data of biochemical testing of the exhaled-air vapor condensate. Nine parameters were investigated, i.e. enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase, alkaline phosphatase (AP), gamma-glutamate amino-transpeptidase (GGT) as well as parameters of protein metabolism--common protein, seromucoid (SC), C-reactive protein and urea. AST, ALT, AP, GGT, SC and urea were acknowledged as the most informative parameters. The results are indicative of that the recovery of metabolic processes in the bronchopulmonary system was not completed.

[Changes in the functional status of the liver in the course of chronic obstructive bronchitis]. / Izmenenie funktsional'nogo sostoianiia pecheni v techenii khronicheskogo obstruktivnogo bronkhita.

Hypoxia conditioned by chronic pulmonary insufficiency is associated in patients with chronic obstructive bronchitis with a more intense free-radical oxidation. A reduced ventilation of the lungs is concurrent in patients with a higher level of malonic aldehyde, as well as with a lower activity of superoxide dismutase and catalase. The liver is involved into the pathological process as a back-feed mechanism in response to the oxidation shift in tissues. Changes of the blood amine-acid spectrum, disproteimenia and hyper-fermentation observed in patients with chronic obstructive bronchitis (COB) denote the impaired hepatocyte condition. The regulating liver function is displayed through an intensified synthesis of endogenous antioxidants: 1) high-molecular--superoxide dismutase, catalase, ceruloplasmia and albumin; 2) low-molecular--uric acid, thiol compounds, biogenic amines, bilirubin, cholesterol as well as molecules of the bioenergetics cycles. As for the early COB stages, a higher level of antioxidant enzymes is more pronounced, whereas, the low-molecule endogenous antioxidants are in the forefront in the disease later stages.

[Effect of omega-3 polyunsaturated fatty acids on activity of glutathione-dependent enzymes in the liver cytosol and blood erythrocytes in rats with experimental chronic bronchitis and in the norm]. / Vliianie omega-3 polinenasyshchennykh zhirnykh kislot na aktivnost' glutationzavisimykh fermentov v tsitozole pecheni i éritrotsitakh krovi krys v norme i pri éksperimental'nom khronicheskom bronkhite.

The influence of omega-3 polyunsaturated fatty acids (omega-3 PUFA) on the activity of glutathione reductase, glutathione transferase and glutathione peroxidase in the liver cytosole and red blood cells of normal rats and animals with experimental chronic bronchitis. omega-3 PUFA ("Tekom" medication) activate glutathione reductase of liver cytosole and glutathionperoxidase in the red blood cells in rats. In the rats with chronic inflammatory process in bronchia omega-3 PUFA corrects the glutathione-dependent systems of detoxication. Effects were more expressed in the liver cytosole in comparison with the red blood cells. The using of omega-3 PUFA as a means for treatment and prophylaxis was more effective than for treatment only.

[Impaired balance of the lung proteolytic system in patients with pneumoconiosis and chronic dust-induced bronchitis]. / Narushenie ravnovesiia sistemy proteoliza legkikh u bol'nykh pnevmokoniozom i khronicheskim pylevym bronkhitom.

The activity of neutrophilic elastase and the level of its major inhibitor--an alpha 1-inhibitor of proteinases were studied to evaluate the protease-antiprotease system in the bronchoalveolar lavage fluid (BALF) of patients with chronic dust-induced bronchitis (CDB) and pneumoconiosis (PC). It was found that CDB, as compared with PC, was characterized by a higher elastase activity in the BALF (70%) and that there were a larger number of patients with elastase activity (40%), which correlated with the detection rate of emphysema. Free elastase activity and relative proteinase alpha 1-inhibitor deficiency suggest that the BALF protease-antiprotease system is impaired in patients with CDB and PC, which is more pronounced in patients with CDB.

Gene expression and immunolocalization of 15-lipoxygenase isozymes in the airway mucosa of smokers with chronic bronchitis.

15-lipoxygenase (15-LO) has been implicated in the inflammation of chronic bronchitis (CB), but it is unclear which of its isoforms, 15-LOa or 15-LOb, is primarily involved. To detect 15-LO gene (mRNA) and protein expression, we have applied in situ hybridization (ISH) and immunohistochemistry (IHC), respectively, to bronchial biopsies obtained from 7 healthy nonsmokers (HNS), 5 healthy smokers (HS), and 8 smokers with CB, and additionally include the airways of lungs resected from 11 asymptomatic smokers (AS) and 11 smokers with CB. Compared with HNS, biopsies in CB demonstrated increased numbers of 15-LOa mRNA+ cells (median: HNS = 31.3/mm(2) versus CB = 84.9/mm(2), P < 0.01) and protein+ cells (HNS = 2.9/mm(2) versus CB = 32.1/mm(2), P < 0.01). The HS group also showed a significant increase in protein+ cells (HNS = 2.9/mm(2) versus HS = 14/mm(2), P < 0.05). In the resected airways, 15-LOa protein+ cells in the submucosal glands of the CB group were more numerous than in the AS group (AS = 33/mm(2) versus CB = 208/mm(2); P < 0.001). 15-LOa mRNA+ and protein+ cells consistently outnumbered 15-LOb by approximately 7- and 5-fold, respectively (P < 0.01). Quantitative reverse transcriptase polymerase chain reaction of complementary biopsies confirmed the increased levels of 15-LOa in CB compared with that in either HNS or HS (P < 0.05). There was no difference between the subject groups with respect to 15-LOb expression. The numbers of cells expressing mRNA for 15-LOa in CB showed a positive association with those expressing interleukin (IL)-4 mRNA (r = 0.80; P < 0.01). We conclude that the upregulation of 15-LO activity in the airways of HS and of smokers with CB primarily involves the 15-LOa isoform: the functional consequences of its association the upregulation of IL-4 in chronic bronchitis requires further study.