Ai-antiproteinase

AP ai-antiproteinase also known as ai-antitrypsin and ai-proteinase inhibitor... 

In this method, ai-antiproteinase inhibits the hydrolytic enzyme elastase, and the remaining elastase activity is measured by monitoring increases in absorbance at410 nm. Martmez-Tome and others (2001) used a method based on this reaction to measure the antioxidant activity of broccoli amino acids and of Mediterranean spices. 

A phenylbutazone radical has been identified spectrophotometrically using pulse radiolysis during which a solution of phenylbutazone was bombarded with hydroxyl radicals (Evans and Aruoma, unpublished work). It is therefore likely that ferryl systems oxidise the drug to free radical forms which cause oxidative damage to arachidonic acid and ai-antiproteinase. 

Those that are strictly proteinases - acting on a protein, rather than a peptide substrate - are discussed first. Members of the serpin family - notably ai-antitrypsin (also called Oi-antiproteinase), inhibit trypsin and similar proteases by binding to the active site. A deficiency of a,-antitrypsin, such as is seen in some genetic disorders expressing mutant -... 

There are several other factors that may play a role in the development of emphysema in ai-PI-sufficient individuals, however, one can conclude that the proteinase-antiproteinase imbalance is involved, as in the case of hereditary emphysema. If the protective shield of the lung is diminished either due to oxidative or proteolytic inactivation of inhibitors, then uncontrolled elastinolytic activity will occur resulting in tissue damage (Fig. 1). This protective shield can... 

The tissue-destructive potential of neutrophil-derived enzymes are countered by powerful plasma antiproteinases. These include ai-proteinase inhibitor, a2-macroglobulin, leukoproteinase inhibitor, plasminogen activator inhibitor (PAI-1), and tissue inhibitor of metalloproteinases (TIMPs) (4). Together, these inhibitors create an antiprotease shield in both plasma and in interstitial fluids. There is growing evidence that this antiprotease shield can be overwhelmed by the over exuberant neutrophil response in chronic wounds. 

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