BACKGROUND Pancreatic cholesterol esterase has three proposed functions in the intestine: 1) to control the bioavailability of cholesterol from dietary cholesterol esters; 2) to contribute to incorporation of cholesterol into mixed micelles; and 3) to aid in transport of free cholesterol to the enterocyte. Inhibitors of cholesterol esterase are anticipated to limit the absorption of dietary cho...

The fraction of human serum designated as C'1 esterase inhibitor is known to inhibit the action of C'1 esterase, a plasma kallikrein, and PF/Dil, an enzyme in plasma enhancing cutaneous vascular permeability. In the present study, C'1 esterase inhibitor has been found to block the actions of plasmin and the C'1r subcomponent of the first component of complement, and to retard the generation of ...

p-Nitrophenyl and cholesteryl-N-alkyl carbamates are good inhibitors of porcine pancreatic cholesterol esterase-catalyzed hydrolysis of p-nitrophenyl butyrate. p-Nitrophenyl-N-butyl and N-octyl carbamates (compounds 1 and 2, respectively) are potent active site-directed irreversible inhibitors of this enzyme. The inhibition of cholesterol esterase by compound 1 or 2 shows saturation kinetics wi...

Angioedema of the upper airways is a severe and potentially life-threatening condition. The incidence has been increasing in the past two decades, primarily due to pharmaceuticals influencing the generation or degradation of the vasoactive molecule bradykinin. Plasma-derived C1-esterase inhibitor concentrate is a well-established treatment option of hereditary and acquired complement C1-esteras...

Vol. 34 No. 6 • June 2009 • P&T® 293 INTRODUCTION Hereditary angioedema (HAE) is a rare genetic disorder resulting from an inherited deficiency or dysfunction of the C1 inhibitor (C1-INH), a molecule that inhibits kallikrein and other serine proteinases. HAE is characterized by un predictable and recurrent attacks of inflammation affecting the hands, feet, face, abdomen, urogenital tract, and l...

Stimulation of platelets and neutrophils occurs during clinical cardiopulmonary bypass. We investigated whether the classical complement. contact. or fibrinolytic pathways are activated as potential sources of neutrophil agonists. Using enzyme-linked immunosorbent “sandwich” assays specific for Cl 8-C1 -and kallikrein-C1 -inhibitor complexes respectively. we found that there was a modest increa...

Bioassay-guided fractionation of methanol extract of Ganoderma lucidum gave a pure cholesterol esterase inhibitor. On the basis of spectroscopic analysis and comparison with data from the literature, its structure was identified as 5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (compound I). Compound (I) inhibited cholesterol esterase with an IC50 value of 42 micronM. A Lineweaver-Burk plot r...

Studies on an esterase derived from partially purified preparations of the first component of complement are described. The esterase hydrolyzed certain synthetic amino acid esters, among which N-acetyl-L-tyrosine ethyl ester was most susceptible. This was hydrolyzed maximally between pH 7.5 and 8.2, and at 41 degrees C. The esterase could not be identified with other previously described hydrol...

Effect of genistein, a protein tyrosine kinase inhibitor, on TAME-esterase induced contractions were studied on rat aorta strips in vitro. Data showed that TAME-esterase induced contractions were concentration dependent and these contractions were significantly inhibited when rat aorta strips were pre-incubated with genistein. The present findings provide evidence for the possible contribution ...