is often associated with an imbalance of protease-antiprotease ..

Acquisition of M. catarrhalis in COPD causes increased airway inflammation and worsening protease-antiprotease imbalance during exacerbations and also in colonization, even in the absence of increased symptoms. These effects could contribute to progression of airway disease in COPD.

the protease-antiprotease imbalance hypothesis

inactivation of antiproteases is central to the protease–antiprotease imbalance hypothesis.

the protease-antiprotease hypothesis

Studies of collagen and elastin in pulmonary emphysema have been controversial. The problems involve methodologic differences; often whole lungs have been sampled and the types of emphysema have not been classified. Quantification of collagen and elastin is important since the increase in collagen supports the inflammatory-repair hypothesis of emphysema, which has been recently revived. On the other hand, loss of elastin supports the protease-antiprotease hypothesis. Accordingly, we measured collagen (hydroxyproline) and elastin (desmosine) in 147 small samples of human lungs removed for cancer. The amount and type of collagen were also assessed histochemically in tissue blocks adjacent to the tissue used for the biochemical analysis. We found that collagen in the homogenates was increased only in irregular air-space enlargement, but histochemically, collagen was consistently increased in centriacinar, distal acinar, and irregular air- space enlargement sections. Elastin was decreased in all grades of panacinar air-space enlargement and also in severe centriacinar air-space enlargement. Our data support both the protease-antiprotease imbalance hypothesis in panacinar and the inflammatory-repair hypothesis in centriacinar, distal acinar, and irregular air-space enlargement.

both the protease-antiprotease imbalance hypothesis in …

N2 - Studies of collagen and elastin in pulmonary emphysema have been controversial. The problems involve methodologic differences; often whole lungs have been sampled and the types of emphysema have not been classified. Quantification of collagen and elastin is important since the increase in collagen supports the inflammatory-repair hypothesis of emphysema, which has been recently revived. On the other hand, loss of elastin supports the protease-antiprotease hypothesis. Accordingly, we measured collagen (hydroxyproline) and elastin (desmosine) in 147 small samples of human lungs removed for cancer. The amount and type of collagen were also assessed histochemically in tissue blocks adjacent to the tissue used for the biochemical analysis. We found that collagen in the homogenates was increased only in irregular air-space enlargement, but histochemically, collagen was consistently increased in centriacinar, distal acinar, and irregular air- space enlargement sections. Elastin was decreased in all grades of panacinar air-space enlargement and also in severe centriacinar air-space enlargement. Our data support both the protease-antiprotease imbalance hypothesis in panacinar and the inflammatory-repair hypothesis in centriacinar, distal acinar, and irregular air-space enlargement.

Smoking is associated with lung inflammation and a protease-antiprotease imbalance
a protease–antiprotease imbalance caused by an excess of proteases released by inflammatory ..

An imbalance of protease-antiprotease ..

These data suggest that serine protease inhibitors attenuate the CSE-induced release of NCA and MCA from human fetal lung fibroblasts and that the inhibitory action of antiproteases might depend on NF-κB signaling pathway.AB - Smoking is associated with lung inflammation and a protease-antiprotease imbalance.

the oxidant–antioxidant imbalance hypothesis and the protease–antiprotease imbalance hypothesis

The protease-antiprotease imbalance hypothesis.

AB - Studies of collagen and elastin in pulmonary emphysema have been controversial. The problems involve methodologic differences; often whole lungs have been sampled and the types of emphysema have not been classified. Quantification of collagen and elastin is important since the increase in collagen supports the inflammatory-repair hypothesis of emphysema, which has been recently revived. On the other hand, loss of elastin supports the protease-antiprotease hypothesis. Accordingly, we measured collagen (hydroxyproline) and elastin (desmosine) in 147 small samples of human lungs removed for cancer. The amount and type of collagen were also assessed histochemically in tissue blocks adjacent to the tissue used for the biochemical analysis. We found that collagen in the homogenates was increased only in irregular air-space enlargement, but histochemically, collagen was consistently increased in centriacinar, distal acinar, and irregular air- space enlargement sections. Elastin was decreased in all grades of panacinar air-space enlargement and also in severe centriacinar air-space enlargement. Our data support both the protease-antiprotease imbalance hypothesis in panacinar and the inflammatory-repair hypothesis in centriacinar, distal acinar, and irregular air-space enlargement.

An imbalance of protease-antiprotease activity is also detected in the airways of patients with ..

the protease-antiprotease hypothesis.

We decided to study the effects of acquisition of pathogenic bacteria in COPD patients by individual bacterial species in order to minimize the variability in host response to different bacterial species. M. catarrhalis demonstrates well-defined periods of carriage in COPD and causes approximately 10% of acute exacerbations in COPD []. Therefore, we chose M. catarrhalis as the index pathogen in this study. Our hypothesis was that acquisition of a new strain of M. catarrhalis in COPD enhances airway inflammation from baseline and alters the protease-antiprotease balance towards a more proteolytic environment. We further hypothesize that these changes are greater during exacerbations associated with M. catarrhalis as compared to colonization by this pathogen.