Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Secretory leukocyte protease inhibitor (SLPI) and elafin are structurally similar, low-molecular-weight antiproteases produced in the lung. We have developed a simple method for distinguishing the antiprotease activities of SLPI and elafin in lung lavage fluid from those of alpha 1-antitrypsin (alpha 1-AT) that is based on the resistance of the low-molecular-weight antiproteases to inactivation by cetyltrimethylammonium bromide. In a study of 23 healthy, nonsmoking volunteers, we found that the low-molecular-weight antiproteases accounted for 22 +/- 2% (mean +/- SEM, n = 23) of the total neutrophil elastase-inhibitory capacity of human bronchoalveolar lavage fluid (BALF). Elafin activity was below the limit of detection. SLPI activity (as measured by inhibition of alpha-chymotrypsin) accounted for 72 +/- 4% (mean +/- SEM, n = 23) of the low-molecular-weight antiprotease activity in BALF. Measurements of SLPI in the lavage fluid samples by enzyme-linked immunosorbent assay (ELISA) agreed closely with values obtained by measuring the activity of this inhibitor. The activity of the low-molecular-weight antiproteases decreased significantly (p < 0.05), from 9.0 +/- 0.8 to 7.0 +/- 0.6 pmol of neutrophil elastase inhibited per mL (mean +/- SEM, n = 23), following acute ozone exposure.
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PMID:Contribution of secretory leukocyte proteinase inhibitor to the antiprotease defense system of the peripheral lung: effect of ozone-induced acute inflammation. 758

Alpha-1-protease inhibitor (alpha(1)-PI) and secretory leukocyte protease inhibitor (SLPI) are two natural airway serine protease inhibitors. While inhibition of neutrophil elastase is a function common to both alpha(1)-PI and SLPI, we showed previously that they exhibit different patterns of protection against antigen-induced changes in airway function in allergic sheep. Specifically, the protective effect seen with SLPI was similar to the profile of action of synthetic tryptase inhibitors in the model. Based on these data, and the fact that tryptase is a serine protease, we hypothesized that SLPI, but not alpha(1)-PI, would block tryptase-induced bronchoconstriction. To test this, we compared the responses to inhaled tryptase in five sheep without treatment or after treatment with either aerosol alpha(1)-PI (10 mg) or aerosol SLPI (50 mg). The doses of alpha(1)-PI and SLPI selected had been shown to be effective in previous antigen-provocation studies. Treatments were given 30 min before aerosol challenge with tryptase (500 ng). Tryptase alone increased (mean+/-SEM) pulmonary resistance (R(L)) 142 +/- 24% over baseline. Pretreatment with alpha(1)-PI had no effect on the tryptase response (R(L)increased 122 +/- 20%). Pretreatment with SLPI, however, blocked the tryptase-induced response (R(L) increased only 40 +/- 4% P<0.05 vs. tryptase). These are the first studies comparing the inhibitory activity of SLPI and alpha(1)-PI on inhaled tryptase-induced bronchoconstriction. We conclude that, in vivo, SLPI, but not alpha(1)-PI, can block tryptase-induced bronchoconstriction and that this activity may explain the differential effects of these two serine protease inhibitors on antigen-induced airway responses in allergic sheep.
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PMID:Secretory leukocyte protease inhibitor, but not alpha-1 protease inhibitor, blocks tryptase-induced bronchoconstriction. 1127 91

Previous studies identified serine, cysteine and metalloproteases in normal aqueous humours (AH) and suggested that a balance between proteases and their inhibitors may play a role in the modulation of the AH outflow. We aimed to determine whether secretory leukocyte protease inhibitor (SLPI), a serine protease inhibitor, is present in AH of patients with cataract and other eye pathologies. AH was collected from 117 cataract patients of which 55 were diagnosed with more when one eye disease: cataract only (n=62), pseudoexfoliation (PEX) (n=26), glaucoma (n=6), diabetes retinopathy (n=4), iritis-uveitis (n=4) and macular degeneration (n=28). The total protein in AH was determined by a Bradford assay and SLPI was analyzed by Western blot and ELISA methods. The average concentration of total protein and SLPI in AH samples was 160+/-15 microg/ml (n=117, +/-SEM) and 500+/-94 pg/ml (n=105), respectively. The cataract patients with additional eye disease(s) showed higher protein levels (201+/-35 microg/ml) than cataract (controls) (128+/-31 microg/ml), P<0.01. It is noteworthy that no correlation was found between SLPI and the total protein concentrations in AH, but SLPI was positively correlated with age (r=0.2, P<0.05). No statistical difference in SLPI levels was found between controls (cataract) and other pathologies, while patients with iritis/uveitis had higher SLPI levels compared to those with diabetes (P<0.05). We show here for the first time that SLPI is present in AH and may play a role as well as serve as a marker in pathological states.
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PMID:Secreted leukocyte protease inhibitor is present in aqueous humours from cataracts and other eye pathologies. 1620 5