Lipase therapeutic enzyme

Mecfianism of Action A gastric and pancreatic lipase inhibitor that inhibits absorption of dietary fats by inactivating gastric and pancreatic enzymes. Therapeutic Effect Resulting caloric deficit may positively affect weight control. 

The biological and pharmaceutical properties of oxetanes have been highlighted throughout the chapter when other aspects such as their synthesis is described. For example, as discussed in Section 2.05.11, oxetanones form part of the structure of potent inhibitors of lipases and other enzymes. The naturally occurring amino acid oxetin is used as an antibiotic, and foldamers derived from analogues of oxetin have other potential therapeutic uses. The antiobesity drug tetrahydrolipstatin 119 was described in Section 2.05.11 and the /3-lactone F-244 (1223 A) has been reported with antibiotic properties <1998BMC1255>. 

Four major enzyme groups are secreted lipolytic, proteolytic, amylolytic, and nucleic acid splitting enzymes. These pancreatic enzymes, some of which are secreted in multipile forms, possess specificities complementary to die intestinal membrane-bound enzymes (Tabic 1). Fresh, uncontsnkinated pancreatic juice is without proteolytic activity because these enzymes am in the form of inactive zymogens. An important fraction of the calcium in pancreatic juice accompanies the enzymes, especially ct-amylase. Human pancreatic juice is moat dose to that of the pig, with high proportions of lipase and a-amylase in comparison with other mammals [1]. Therefore, pig pancreas extract, pancreatin, has up to now been die oreferred enzvme source for therapeutic tuncreas substitution. 

Abstract The major enzymatic barrier to the absorption of macromolecules, particularly therapeutic peptides, is the pancreatic enzymes the peptidases, nucleases, lipases and esterases that are secreted in considerable quantities into the intestinal lumen and rapidly hydrolyse macromolecules and lipids. In the case of the peptidases, they work in a co-ordinated fashion, whereby the action of the pancreatic enzymes is augmented by those in the brush borders of the intestinal cells. The sloughing-off of mucosal cells into the lumen also furnishes a mixture of enzymes that are a threat to macromolecules. As the specificity and activity of the enzymes are not always predictable, during pharmaceutical development it is important to test the stability of therapeutic macromolecules, and novel macromolecular-containing or lipid-containing formulations, in the presence of mixtures of pancreatic enzymes and bile salts, or in animal intestinal washouts or ideally, aspirates of human intestinal contents. 

Given the uncertainties of the quantities and the precise specificities of many digestive enzymes, notably the endopeptidases, and the surprises that biological systems sometimes throw up (who would have expected chitosan to be hydrolysed by pepsin, pancreatin, a lipase or a-amylase as has been reported (Muzzarelli 1997 Muzzarelli et al. 1995 Yalpani and Pantaleone 1994)) any therapeutic macromolecule or formulation destined for oral use should be... 

In the case of biocatalysis, enzymes [3] and catalytic antibodies [4] have attracted most attention. Since enzymes are inherently the more active catalysts, they have been used most often. Indeed, many industrial processes for the enantioselective production of certain chiral intermediates are based on the application of enzymes, as in the lipase-catalyzed kinetic resolution of an epoxy-ester used in the production of the anti-hypertensive therapeutic Diltiazem [5]. Recently, it has been noted that there seems to be a trend in industry to use enzymes more often than in the past... 

The types of enzymes used by organic chemists vary widely and include such well-known biocataiysts as lipases, esterases, oxidoreductases, oxinitrilases, transferases and aldolases [4]. An example which illustrates the industrial application of a lipase concerns the kinetic resolution of a chiral epoxy ester used as the key intermediate in the synthesis of the calcium antagonist Diltiazem, a major therapeutic in the treatment of high blood pressure [6] (Fig. 1). In developing the industrial process for the production of this drug, many different lipases were screened, but only the bacterial lipase from Serratia marescens showed both a sufficiently high activity and enantioselectivity. The intermediate is produced industrially on a scale of 50 tons/year. 

Chemical transformations carried out on the parent alkaloid (-)-162 are surprisingly uncommon when one considers current levels of interest in the therapeutic properties of the compound and its analogs. The stable hydrohalide salts have been described in a patent relating to the compound s antitumor potential 142). Several 2- and 8-0-acyl esters of 162 have been reported 143). The use of the enzyme subtilisin in pyridine permitted selective synthesis of 2-0-butyrylswainsonine (235) from 162 in 23% yield, while catalysis by porcine pancreatic lipase gave 235 (6%) and 1,2-di-O-butyrylswainsonine (236) (31%) 97). Swainsonine has been tethered at C-7 to an agarose matrix for evaluation as an affinity material for mannosidases 144). 

A09A A Enzyme Preparations Enzymes can be used therapeutically. Some are of animal origin (from the stomach and pancreas of food animals), some of vegetable origin and others of microbiological origin. Examples of the first type include pepsin and pancreatin, a mixture of amylase, lipase and trypsin (a protease) which catalyses the metabolism of proteins into smaller peptides and amino-acids. Pancreatin is frequently prescribed for patients with cystic fibrosis. 

Corn seed-derived dog gastric lipase is under development by Meristem Therapeutics for the treatment of gastric lipase deficiency (steatorrhea), neonatal deficient pancreatic function, or when pancreatic function is compromised by diseases such as cystic fibrosis or chronic alcoholism [159]. The absence of gastric lipase in steatorrhea patients prevents the digestion of food lipids. Pre-term infants have difficulty digesting lipids and, unless they are breast-fed, have no access to this enzyme. 

Other recombinant versions of gastric lipases are available from yeast. Pseudomonas and filamentous fungi [369]. Sheep milk-derived human bile salt-stimulated H-pase (BSSL) - an enzyme produced in the pancreas and in human milk - was developed by PPL Therapeutics for similar indications, and it is discussed below [63]. 

P. pastoris is most favorably employed to produce secreted recombinant proteins. The major advantage is that the product is derived in a quite pure form after cell removal, so that recovery and purification are much easier than from cell lysates. Secondly, proteins that are naturally secreted in their native host often require the passage through the secretory pathway of the recombinant host for correct folding and processing. Most human proteins of potential therapeutic value are secretory proteins (antibodies, hormones, cytokines, enzymes), as well as many technical enzymes (e.g., cellulases, proteases, lipases, etc.), so that the secretory route is of high practical value. 

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