[Evaluation of matrix metalloproteinases (pro-MMP-1, MMP-2,8) and their inhibitor (TIMP-1) contents in patients with occupational lung diseases].

Studies of matrix metalloproteinases in patients with occupational bronchopulmonary diseases and in individuals exposed to asbestos dust revealed hyperactivated protease system--lower level of MMP-1 proenzyme and increased production of TIMP-1 (metalloproteinases inhibitor)--in all the examinees groups. Patients with pneumoconiosis and occupational dust bronchitis demonstrated increased neutrophilic elastase that is activator of metalloproteinases inducing sclerotic changes and pulmonary fibrosis.

The chemopreventive agent myoinositol inhibits Akt and extracellular signal-regulated kinase in bronchial lesions from heavy smokers.

Myoinositol is an isomer of glucose that has chemopreventive activity in animal models of cancer. In a recent phase I clinical trial, myoinositol administration correlated with a statistically significant regression of preexisting bronchial dysplastic lesions in heavy smokers. To shed light on the potential mechanisms involved, activation of Akt and extracellular signal-regulated kinase (ERK), two kinases that control cellular proliferation and survival, was assessed in 206 paired bronchial biopsies from 21 patients who participated in this clinical trial. Before myoinositol treatment, strongly positive staining for activation of Akt was detected in 27% of hyperplastic/metaplastic lesions and 58% of dysplastic lesions (P = 0.05, chi(2) test). There was also a trend toward increased activation of ERK (28% in regions of hyperplasia/metaplasia to 42% of dysplastic lesions). Following myoinositol treatment, significant decreases in Akt and ERK phosphorylation were observed in dysplastic (P < 0.01 and 0.05, respectively) but not hyperplastic/metaplastic lesions (P > 0.05). In vitro, myoinositol decreased endogenous and tobacco carcinogen-induced activation of Akt and ERK in immortalized human bronchial epithelial cells, which decreased cell proliferation and induced a G(1)-S cell cycle arrest. These results show that the phenotypic progression of premalignant bronchial lesions from smokers correlates with increased activation of Akt and ERK and that these kinases are targets of myoinositol. Moreover, they suggest that myoinositol might cause regression of bronchial dysplastic lesions through inhibition of active Akt and ERK.

Matrix metalloproteinase-1 polymorphism in Taiwanese patients with endobronchial tuberculosis.

Endobronchial tuberculosis (TB) often leads to some degree of tracheobronchial stenosis. Because matrix metalloproteinases (MMPs) play an essential role in tissue remodeling in the airways, we investigated the role of MMP-1 polymorphism in patients with endobronchial TB. One hundred and one cases of pulmonary TB in Taiwanese patients were genotyped for the 1G/2G polymorphism of MMP-1 promoter (-1607 bp). Bronchoscopic examination was performed to determine the presence of endobronchial involvement. Levels of MMP-1 in peripheral blood monocytes and in bronchial biopsies were also determined. 1G genotypes of MMP-1 polymorphism, containing at least one 1G allele, were associated with the presence of endobronchial TB. Using multivariate analysis, 1G genotypes and female gender were independent predictors of the development of endobronchial TB. Endobronchial TB patients with 1G genotypes had a 9.86-fold greater risk of developing tracheobronchial stenosis. IL-1beta increased levels of MMP-1 in peripheral blood monocytes of TB patients with 1G genotypes. MMP-1 activity was also present in the endobronchial TB granuloma from patients with 1G/1G genotype. 1G genotypes of MMP-1 polymorphism were associated with a greater risk of developing tracheobronchial stenosis through up-regulation of MMP-1 activity.

Acetylcholine and tachykinin receptor antagonists attenuate wood smoke-induced bronchoconstriction in guinea pigs.

To study the mechanisms of wood smoke-induced bronchoconstriction, we measured total lung resistance (RL) and dynamic lung compliance (Cdyn) in anesthetized and mechanically ventilated guinea pigs. Airway exposure to various doses of wood smoke (lauan wood; 5, 10, and 15 breaths) resulted in a dose-dependent increase in RL and decrease in Cdyn. The smoke-induced changes in RL and Cdyn were significantly attenuated by pretreatment with atropine, CP-96,345 [(2S,3S)-cis-2-(diphenylmethyl)-N-((2-methoxyphenyl)-methyl)-1-aza bicyclo(2.2.2.)-octan-3-amine; a tachykinin NK1 receptor antagonist], and SR-48,968 [(S)-N-methyl-N(4-(4-acetylamino-4-phenylpiperidino)-2-(3,4-dichlorophen yl)-butyl)benzamide; a tachykinin NK2 receptor antagonist] in combination, atropine alone, and SR-48,968 alone, but were not significantly affected by pretreatment with the inactive enantiomers of CP-96,345 and SR-48,968, CP-96,345 alone, indomethacin (a cyclooxygenase inhibitor), and MK-571 [((3-(3-(2-(7-chloro-2-quinolinyl)ethenyl)phenyl((3-dimethyl amino-3-oxo-propyl)thio)methyl)propanoic acid; a leukotriene D4 receptor antagonist]. The activity of airway neutral endopeptidase, a major enzyme for tachykinin degradation, was not significantly influenced by wood smoke during the development of bronchoconstriction. We conclude that: (1) both cholinergic mechanisms and endogenous tachykinins, but not cyclooxygenase products or leukotriene D4, play an important role in the acute bronchoconstriction induced by wood smoke, and (2) the contribution of tachykinins to this airway response is primarily mediated via the activation of tachykinin NK2 receptors, but is not associated with inactivation of the airway neutral endopeptidase.

Purification, characterization, and localization of a novel trypsin-like protease found in the human airway.

A novel trypsin-like protease was purified to homogeneity from the sputum of patients with chronic airway diseases, by sequential chromatographic procedures. The enzyme migrated on SDS-polyacrylamide gel electrophoresis to a position corresponding to a molecular weight of 28 kDa under both reducing and non-reducing conditions, and showed an apparent molecular weight of 27 kDa by gel filtration, indicating that it exists as a monomer. It had an NH2-terminal sequence of Ile-Leu-Gly-Gly-Thr-Glu-Ala-Glu-Glu-Gly-Ser-Trp-Pro-Trp-Gln-Val-Ser-Leu- Arg-Leu, which differed from that of any known protease. Studies with model peptide substrates showed that the enzyme preferentially cleaves the COOH-terminal side of arginine residues at the P1 position of certain peptides, cleaving Boc-Phe-Ser-Arg-4-methylcoumaryl-7-amide most efficiently and having an optimum pH of 8.6 with this substrate. The enzyme was strongly inhibited by diisopropyl fluorophosphate, leupeptin, antipain, aprotinin, and soybean trypsin inhibitor, but hardly inhibited by secretory leukocyte protease inhibitor at 10 microM. An immunohistochemical study indicated that the enzyme is located in the cells of the submucosal serous glands of the bronchi and trachea. These results suggest that the enzyme is secreted from submucosal serous glands onto the mucous membrane in patients with chronic airway diseases.

[On phenotype and genotype features of serum and erythrocyte proteins in occupation-related bronchopulmonary pathology]. / Fenotipicheskie i genotipicheskie osobennosti syvorotochnykh i éritrotsitarnykh belkov pri professional'noi bronkholegochnoi patologii.

Electrophoresis and isoelectric focusing assessed distribution of phenotypic and gene frequency for 7 highly polymorphic proteins in 163 patients having occupational chronic bronchitis, pneumoconiosis and bronchial asthma. Phenotypic frequency studies, when compared to the reference group, revealed significant differences in the following parameters: proteinase inhibitor, 3rd component of complement, transferrin, serum blood-group specific component, phosphoglucomutase of RBC. Gene frequency studies revealed the significant differences in 3rd component of complement (C3), transferrin (Tf) and phosphoglucomutase of RBC (PGM): the patients demonstrated increased amounts of C3 F, Tf C3 and PGM 2b alleles. The results could be used for individual forecasting the risk of occupational diseases and for choosing the individual prophylactics.

Role of neutral endopeptidase in exercise-induced bronchoconstriction in asthmatic subjects.

The membrane-bound metalloproteinase, neutral endopeptidase (NEP), is a degrading enzyme of both bronchoconstrictor and bronchodilator peptides within the airways. To examine the role of NEP in exercise-induced bronchoconstriction (EIB) in asthmatic subjects, we used inhaled thiorphan, a NEP inhibitor, as pretreatment to a 6-min standardized exercise challenge. Thirteen clinically stable asthmatic subjects participated in this double-blind, placebo-controlled, crossover study that was performed on 2 days separated by 48 h. Thiorphan was administered by two inhalations of 0.5 ml containing 1.25 mg/ml. Subsequently, exercise was performed on a bicycle ergometer at 40-50% of predicted maximal voluntary ventilation while inhaling dry air (20 degrees C, relative humidity 6%). The airway response to exercise was measured by forced expiratory volume in 1 s (FEV1) every 3 min, up to 30 min postexercise challenge, and was expressed both as the maximal percent fall in FEV1 from baseline and as the area under the time-response curve (AUC) (0-30 min). The acute effects of both pretreatments on baseline FEV1 were not different (P > 0.2), neither was there any difference in maximal percent fall in FEV1 between thiorphan and placebo (P > 0.7). However, compared with placebo, thiorphan reduced the AUC by, on average, 26% [AUC (0-30 min, +/-SE): 213.6 +/- 47.7 (thiorphan) and 288.6 +/- 46.0%fall.h (placebo); P = 0.047]. These data indicate that NEP inhibition by thiorphan reduces EIB during the recovery period. This suggests that bronchodilator NEP substrates, such as vasoactive intestinal polypeptide or atrial natriuretic peptide, modulate EIB in patients with asthma.

[Proteinases in the bronchopulmonary apparatus of rats with bronchial anaphylaxis]. / Izuchenie proteinaz v bronkholegochnom apparate krys s bronkhial'noi anafilaksiei.

Proteolytic activity was studied in bronchoalveolar lavage in dynamics of rat bronchial anaphylaxis; in the disease alkaline proteinases were activated. Physico-chemical properties of an alkaline proteinase, isolated from the rat lavage, were studied. Quantitative metabolic patterns of the enzyme metabolism, involving the rates of its synthesis and decomposition as well as a period of the newly synthesized protein functioning, were evaluated. Under conditions of bronchial anaphylaxis the parameters of the proteinase turnover were altered in bronchopulmonary system.

Intermediate alpha 1-antitrypsin deficiency in atopic allergy.

In a population of over 200 patients with atopic bronchial disease, significantly increased frequencies of the alpha 1-antitrypsin Pi-types of intermediate deficiency (Pi MZ and Pi MS) were found. As far as we are aware of, this report is the first in which strictly objective criteria for patient classification with respect to atopy have been used. A possible biochemical basis for the phenomenon is presented.

[Activity of granulocyte proteinases and level of acid-stable proteinase inhibitors in the bronchial secretions of children with bronchopathies of different etiology]. / Aktivnost' proteinaz granulotsitov i uroven' kislotostabil'nykh ingibitorov proteinaz v bronkhial'nom sekrete detei s bronkhopatiiami razlichnoi étiologii.

Activities of elastase- and trypsin-like proteinases from granulocytes as well as content of their acid-stable inhibitors were studied in 80 samples of the bronchial secretory products obtained from 34 children from 4 to 15 years old suffering from various forms of bronchopulmonary pathology/primary chronic pneumonia, Cartagener's syndrom, mucoviscidosis, pulmonary malformations. Normal bronchial secretory products were characterized by high content of the acid-stable inhibitors as well as by absence of the granulocytic proteinases activity. Development of inflammatory impairments in bronchi was accompanied by 2-3-fold decrease in content of the inhibitors with simultaneous increase in the enzymatic activity. The data obtained suggest that the relationship between activity of granulocytic proteinases and content of acid-stable inhibitors in bronchial secretory products might be considered as an important index of inflammatory processes in bronchi. De novo synthesis of acid-stable inhibitors in lungs appears to be decreased in the course of development of inflammation.

[Diseases associated with chronic bronchopathies and plasma alpha-1-antitrypsin deficiency (author's transl)]. / Procesos asociados a broncopatías crónicas con deficiencias plasmáticas de alfa-1-antitripsina.

Two groups of patients were selected according to their plasma levels of alpha-1-antitrypsin deficiency from among 58 patients with a chronic bronchopathy. Group I had normal plasma levels of alpha-1-antytrypsin; group II had plasma values lower than normal. The pathologic conditions associated with chronic bronchopathies were studied in both groups and so were the gasometric characteristics of the same. Chronic bronchopathies in subjects belonging to group II showed a clear tendency to present normal levels of pCO2 and hydrogen ions possibly related to a greater bronchial impairment in these patients. Independently of the genetic characteristics of plasma alpha-1-antitrypsin deficiency, its general levels are the real indication of its possible etiopathogenic action. Patients with recurrent plasma alpha-1-antitrypsin deficiency, its general levels are the real indication of its possible etiopathogenic action. Patients with recurrent plasma alpha-1-antitrypsin deficiency are more susceptible to bacterial infections, liver cirrhosis, diabetes, and allergic states. All this would be related to the protective effect of this protein fraction, and its reduction according to the most recognized theories would decrease the resistance of hepatic and pancreatic cells.

Activity of serum inhibitory proteases in bronchial secretions from children with various chronic non-specific respiratory diseases.

In a group of 223 children with various chronic, non-specific respiratory diseases, the levels of serum inhibitory proteolytic enzymes in bronchial secretions was measured. Activity of inhibitory proteolytic enzymes was analyzed according to the nature of bronchial lesions observed at bronchoscopy and character and cellular composition of bronchial secretion. Statistically significant increase of the mean inhibitory value in comparison to values in the control group, was found in children with recurrent bronchitis (a-1-AT), cystic fibrosis (a-1-AT and a-1-X), chronic bronchitis (a-1-X), bronchiectases (a-1-X) and in children with obstructive bronchitis (a-2-M).