Elastase Activity

In the past number of years a number of studies have shown that in a variety of diseases there is a significant oxidation of Met residues to Met(O) in specific proteins that results in a loss of biological activity. These diseases include cataracts, rheumatoid arthritis, adult respiratory distress syndrome and emphysema. The most convincing evidence that Met(O) in proteins may be involved in the etiology of a pathological condition comes from studies with a-l-PI. It is well accepted that a-l-PI is inactivated upon oxidation of its Met residues. A decreased activity of a-l-PI in lung tissue that would result in an increased elastase activity has been associated with pulmonary emphysema. In patients who have a... 

There are other substrates for the E. coli Met(0)-peptide reductase, one of which is Met(0)-a-l-PI. The native protein is the major serum elastase inhibitor that functions by forming a binary complex with elastase which inhibits its activity. Met(0)-a-l-PI, on the other hand, which can be formed by treatment of the protein with JV-chlorosuccinimide, cannot form a complex with elastase and therefore is not able to inhibit elastase activity . Table 6 shows, however, that when Met(0)-a-l-PI is incubated in the presence of Met(0)-peptide reductase and dithiothreitol the protein regains its ability to form a complex with elastase and inhibit elastase activity . Similar to results found with Met(0)-L12 reduced thioredoxin could replace the dithiothreitol as reductant in the enzymatic reaction. 

A substance known as elastase is involved in various inflammatory diseases such as arthritis, pulmonary emphysema, and pancreatitis. Elastase activity can be inhibited by a compound known as elasnin, obtained from a microorganism. 

A significant advance in the understanding of the anti-inflammatory properties of Bupleurum fruticescens has been provided by Prieto et al. (36). The showed that a methanol extract from the aerial parts had a significant effect on 5-lipoxygenase activity, inhibiting both LTB4 and 5(S)-HETE production, with IC50 values of 112 and 95 (xg/mL, respectively. At concentrations of 200 (Xg/mL, the extract inhibited COX-1 (90%) and elastase activities (54%). What are the principles involved here, saponin ... 

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 substance known as elastase is involved in arthritis, various inflammations, pulmonary emphysema, and pancreatitis. Elastase activity can be inhibited by a compound known as elasnin, obtained from the culture broth of a particular microorganism. The structure of elasnin is shown. A synthesis of elasnin has been reported which utilized compound E as a key intermediate. Suggest a synthesis of compound E from methyl hexanoate and hexanal. 

Gonzales, J. R., Hermann, J. M., Boedeker, R. H., Francz, P. L, Biesalski, H. K., and Meyle, J. (2001). Concentration of interleukin-1 p and neutrophil elastase activity in gingival crevi-cular fluid during experimental gingivitis. /. Clin. Periodontol. 28,544—549. 

C. Deficiency in dietary vitamin C D Decreased elastase activity E. Increase collaginase activity... 

Correct answer = B. o1-Antitrypsin deficiency is a genetic disorder that can cause pulmonary emphysema even in the absence of cigarette use. An deficiency of a1-antitrypsin permits increased elastase activity to destroy elastin in the alveolar walls, even in nonsmokers. a1-antitrypsin deficiency should be suspected when chronic obstructive pulmonary disease develops in a patient younger than 45 years who does not have a history of chronic bronchitis or tobacco use, or when multiple family members develop obstructive lung disease at an early age. 

Bahgat, M. and Ruppel, A. (2002) Biochemical comparison of the serine protease (elastase) activities in cercar-ial secretions from Trichobilharzia ocellata and Schistosoma mansoni. Parasitology Research 88, 495-500. 

Collier A, Jackson M, Bell D, Patrick AW, Matthews DM, Young RJ, et al. Neutrophil activation detected by increased neutrophil elastase activity in type 1 (insulin-dependent) diabetes mellitus. Diabetes Res 1989 10 135-138. 

Lestienne, P. and Bieth, J.G. 1980 Activation of human leukocyte elastase activity by excess substrate, hydro-phobic solvents and ionic strengths. J. Biol. Chem. 255, 9289-9294. 

Human leukocyte elastase (40mU/ml) and 0.1% of the experimental agent were applied to the substrate methyl-O-succinate alanine alanine proline valine-/ -nitroanilide, then incubated at 37°C for 60 minutes. Elastase activity was then evaluated by spectrophotometry. Testing results are provided in Tables 1 and 2. 

Elastase activity is not a universal property of proteolytic sulfhydryl-activated enzymes. There are abundant reports in the literature describing the disappearance of elastic fibers in vivo preceding the repair of damaged tissues, but there is no evidence as to how this is brought about. The tissue cathepsins, most of which are SH-activated, have received little systematic study, but Thomas and Partridge (1960) reported that cathepsins extracted from kidney and spleen by the method of De La Haba et al. (1955) did not digest elastin either in the presence or the absence of cysteine. 

It was found that a keratinase from Streptomyces fradiae had the greatest elastase activity of any of the enzyme preparations tested. A similar line of thought recently led Fiizi et al. (1960) to examine the use of elastase for the isolation of cells during tissue culture. The effect of pancreatic elastase in separating the cells for the preparation of cell suspensions was examined. It was found that pancreatic elastase solutions in phosphate buffer were effective within 3-10 min for rabbit epithelial cell cultures and human amnion epithelial cell cultures. The toxicity of the elastase preparations towards the cells did not appear to exceed that of trypsin. 

Two new cyclodepsipeptides, pitipeptolides A 297 and B 298, were isolated from a population of marine cyanobacterium Lyngbya majuscula collected at Piti Bomb Holes, Guam. Compounds 297 and 298 possessed stimulated elastase activity and moderate anti-mycobacterial activity and both compounds exhibited weak C5dotoxicity against LoVo cancer cells with IC50 values of 2.25 and 1.95pg mL respectively. 

AAT can be quantified by all immunochemical methods, with immunoturbidimetry and immunonephelometry the most commonly used methods. Because it constitutes about 90% of the serum inhibition of trypsin or elastase activity against small substrates, such as benzoyl-DL-arginine p-nitroanilide, it can also be semiquantified by the inhibitory capacity of serum for these enzymes however, this assay is not specific for AAT. 

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