Pancreatic lipase in vitro

Krokan, H.E., Bjerve, K.S. and Mork, E. (1993) The enteral bioavailability of eicosapen-taenoic acid and docosahexaenoic acids is as good from ethyl ester as from glyceryl ester in spite of lower hydrolytic rates by pancreatic lipase in vitro. Biochim. Biophys. Acta. 1168 59-67. 

Hadvary, P., Lengsfeld, H. and Wolfer, H. (1988) Inhibition of pancreatic lipase in vitro by the covalent inhibitor tetrahydrolipstatin. Biochem. J. 256, 357-361... 

Marquez-Ruiz, G., Guevel, G., and Doharganes, M.C. (1998) Applications of Chromatographic Techniques to Evaluate Enzymatic Hydrolysis of Oxidized and Polymeric Triglycerides hy Pancreatic Lipase In Vitro, J. Am. Oil Chem. Soc. 75, 119-126. 

Within the small intestine, bile-acid binding interferes with micelle formation. Nauss et al. [268] reported that, in vitro, chitosan binds bile acid micelles in toto, with consequent reduced assimilation of all micelle components, i.e., bile acids, cholesterol, monoglycerides and fatty acids. Moreover, in vitro, chitosan inhibits pancreatic lipase activity [269]. Dissolved chitosan may further depress the activity of lipases by acting as an alternative substrate [270]. 

G. K. E. Scriba, Phenytoin-Lipid Conjugates Chemical, Plasma Esterase-Mediated, and Pancreatic Lipase-Mediated Hydrolysis in vitro, Pharm. Res. 1993, 10, 1181 — 1186. 

Mun, S., Decker, E.A., McClements, D.J. (2007). Influence of emulsifier type on in vitro digestibility of lipid droplets by pancreatic lipase. Food Research International, 40, 770-781. 

In another set of studies, it has been reported that the in vitro digestibility of lipid droplets by pancreatic lipase is significantly affected by emulsifier type (Mun et al, 2006, 2007 Park et al., 2007). Intuitively, one might expect that a thick dense layer of strongly bound protein-polysaccharide complex at the oil-water interface would reduce considerably the in vivo accessibility of lipases, and hence would reduce the rate of human metabolism of fats. Establishment of the validity of this hypothesis must still await consolidation of a substantial body of detailed results from independent systematic studies on a broad range of mixed biopolymer systems. 

Bemback, L fiiacabcig, and G. Hcmcli. The compieie digestion of human milk triacylglyccxol In vitro requires gastric lipase, pancreatic colipase-depcndent lipase and bile salt-stimulated lipase. J. Clio. Invest. Jf5 1221 (1990). 

M. UndsttOm, B. Stentby, and B. BotgstrtJrn. Conceited notion of human carboxyl ester lipase and pancreatic lipase during lipid digestion In vitro Impair-... 

Bernback, S., Blackberg, L., Hernell, O. 1989. The complete digestion of human milk triacyl-glycerol in vitro requires gastric lipase, pancreatic colipase-dependent lipase, and bile salt-stimulated lipase.. / Clin. Invest. 85, 1221-1226. 

The rates of dissolution on the one hand and in vitro hydrolysis of the solid by the enzyme pancreatic lipase on the other hand are given in Fig. 7.4. If dissolution is the first step in the total hydrolysis process, the reaction scheme may be written as... 

Human pancreatic lipase (HPL) alone is inactive in vitro on an emulsified TAG substrate in the presence of supramiceUar concentrations of bile salts such as those found in the small intestine. Bile salts are amphiphilic molecules that bind to the oil-water interface and prevent pancreatic hpase adsorption, and thus hpo-lysis, from occurring [3, 4]. The inhibition by bile salts can, however, be reversed by the specific pancreatic hpase cofactor cohpase [3, 5-7], via the formation of a specific 1 1 hpase-cohpase complex. 

Carriers, I., Rogalska, I., Cudrey, C., Per-RATO, F., Laugier, R. and Verger, R. (1997) In vivo and in vitro studies on the stereoselective hydrolysis of tri- and diglycerides by gastric and pancreatic lipases. Bioorg. Med. Chem. 5, 429-435. 

M. Lindstrom, J. Persson, L. Thum, and B. BorgstrOm. Effect of pancreatic phospholipase A2 and gastric lipase on the action of pancreatic carboxyl ester lipase against lipid substrates in vitro. Biochim. Biophys. Acta 1084 194 (1991). 

Fig. (6) Effects of the aqueous extract of Platycodi radix and inulin isolated from the aqueous extract of Platycodi radix on pancreatic lipase activity in vitro. Results are expressed as mean + s.e.m. of four experiments.

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