Abstract
Human milk fat globules were used to explore how dietary triglycerides are hydrolyzed by pancreatic lipase. These triglycerides were hydrolyzed very slowly by lipase alone as if the surface layer of proteins and phospholipids impeded the action of the enzyme. The inhibition of lipase activity could be overcome by addition either of colipase or of pancreatic phospholipase A2. Colipase enhanced triglyceride hydrolysis in a dose-dependent manner whether bile salts were present or not. Bile salts had no effect on the activity of pancreatic lipase alone but further enhanced the activity at all concentrations of colipase tested. Bile salts were a prerequisite to relieve inhibition of lipase activity by phospholipase A2. Human milk fat globules exposed to phospholipase A2 should be representative of a physiological substrate for pancreatic lipase. A major new observation was that bile salts, even at high concentrations, stimulated triglyceride hydrolysis of such phospholipase-treated globules by pancreatic lipase also in the absence of colipase.
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- Bengtsson G., Olivecrona T. Lipoprotein lipase: some effects of activator proteins. Eur J Biochem. 1980 May;106(2):549–555. doi: 10.1111/j.1432-1033.1980.tb04602.x. [DOI] [PubMed] [Google Scholar]
- Björkstén B., Burman L. G., De Château P., Fredrikzon B., Gothefors L., Hernell O. Collecting and banking human milk: to heat or not to heat? Br Med J. 1980 Sep 20;281(6243):765–769. doi: 10.1136/bmj.281.6243.765. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bläckberg L., Hernell O., Bengtsson G., Olivecrona T. Colipase enhances hydrolysis of dietary triglycerides in the absence of bile salts. J Clin Invest. 1979 Nov;64(5):1303–1308. doi: 10.1172/JCI109586. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Brockerhoff H. On the function of bile salts and proteins as cofactors of lipase. J Biol Chem. 1971 Sep 25;246(18):5828–5831. [PubMed] [Google Scholar]
- Brogström B., Hildebrand H. Lipase and co-lipase activities of human small intestinal contents after a liquid test meal. Scand J Gastroenterol. 1975;10(6):585–591. [PubMed] [Google Scholar]
- DOLE V. P., MEINERTZ H. Microdetermination of long-chain fatty acids in plasma and tissues. J Biol Chem. 1960 Sep;235:2595–2599. [PubMed] [Google Scholar]
- Figarella C., De Caro A., Leupold D., Poley J. R. Congenital pancreatic lipase deficiency. J Pediatr. 1980 Mar;96(3 Pt 1):412–416. doi: 10.1016/s0022-3476(80)80683-4. [DOI] [PubMed] [Google Scholar]
- Fredrikzon B., Olivecrona T. Decrease of lipase and esterase activities in intestinal contents of newborn infants during test meals. Pediatr Res. 1978 May;12(5):631–634. doi: 10.1203/00006450-197805000-00004. [DOI] [PubMed] [Google Scholar]
- Garner C. W., Smith L. C. Hydrolysis of monomolecular films of trioctanoin by porcine pancreatic lipase. Biochem Biophys Res Commun. 1970 May 22;39(4):672–682. doi: 10.1016/0006-291x(70)90258-5. [DOI] [PubMed] [Google Scholar]
- Grand R. J., Watkins J. B., Torti F. M. Development of the human gastrointestinal tract. A review. Gastroenterology. 1976 May;70(5 PT1):790–810. [PubMed] [Google Scholar]
- Hamosh M. A review. Fat digestion in the newborn: role of lingual lipase and preduodenal digestion. Pediatr Res. 1979 May;13(5 Pt 1):615–622. doi: 10.1203/00006450-197905000-00008. [DOI] [PubMed] [Google Scholar]
- Hernell O. Human milk lipases. III. Physiological implications of the bile salt-stimulated lipase. Eur J Clin Invest. 1975 Jun 12;5(3):267–272. doi: 10.1111/j.1365-2362.1975.tb02294.x. [DOI] [PubMed] [Google Scholar]
- Hernell O., Olivecrona T. Human milk lipases. I. Serum-stimulated lipase. J Lipid Res. 1974 Jul;15(4):367–374. [PubMed] [Google Scholar]
- Klein E., Lyman R. B., Jr, Peterson L., Berger R. I. The effect of lecithin on the activity of pancreatic lipase. Life Sci. 1967 Jun 15;6(12):1305–1307. doi: 10.1016/0024-3205(67)90026-4. [DOI] [PubMed] [Google Scholar]
- Maylié M. F., Charles M., Astier M., Desnuelle P. On porcine pancreatic colipase: large scale purification and some properties. Biochem Biophys Res Commun. 1973 May 1;52(1):291–297. doi: 10.1016/0006-291x(73)90986-8. [DOI] [PubMed] [Google Scholar]
- Muller D. P., McCollum J. P., Trompeter R. S., Harries J. T. Proceedings: Studies on the mechanism of fat absorption in congenital isolated lipase deficiency. Gut. 1975 Oct;16(10):838–838. [PubMed] [Google Scholar]
- Murphy G. M., Signer E. Bile acid metabolism in infants and children. Gut. 1974 Feb;15(2):151–163. doi: 10.1136/gut.15.2.151. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Patton S., Keenan T. W. The milk fat globule membrane. Biochim Biophys Acta. 1975 Oct 31;415(3):273–309. doi: 10.1016/0304-4157(75)90011-8. [DOI] [PubMed] [Google Scholar]
- Pieroni G., Verger R. Hydrolysis of mixed monomolecular films of triglyceride/lecithin by pancreatic lipase. J Biol Chem. 1979 Oct 25;254(20):10090–10094. [PubMed] [Google Scholar]
- Porter H. P., Saunders D. R., Tytgat G., Brunser O., Rubin C. E. Fat absorption in bile fistula man. A morphological and biochemical study. Gastroenterology. 1971 Jun;60(6):1008–1019. [PubMed] [Google Scholar]
- Vandermeers A., Vandermeers-Piret M. C., Rathé J., Christophe J. Effect of colipase on adsorption and activity of rat pancreatic lipase on emulsified tributyrin in the presence of bile salt. FEBS Lett. 1975 Jan 1;49(3):334–337. doi: 10.1016/0014-5793(75)80779-4. [DOI] [PubMed] [Google Scholar]
- Verger R., Rietsch J., Desnuelle P. Effects of colipase on hydrolysis of monomolecular films by lipase. J Biol Chem. 1977 Jun 25;252(12):4319–4325. [PubMed] [Google Scholar]
- Verger R., Rietsch J., Van Dam-Mieras M. C., de Haas G. H. Comparative studies of lipase and phospholipase A2 acting on substrate monolayers. J Biol Chem. 1976 May 25;251(10):3128–3133. [PubMed] [Google Scholar]
- Verger R., de Haas G. H., Sarda L., Desnuelle Purification from porcine pancreas of two molecular species with lipase activity. Biochim Biophys Acta. 1969;188(2):272–282. doi: 10.1016/0005-2795(69)90075-0. [DOI] [PubMed] [Google Scholar]
- Watkins J. B. Mechanisms of fat absorption and the development of gastrointestinal function. Pediatr Clin North Am. 1975 Nov;22(4):721–730. doi: 10.1016/s0031-3955(16)33203-5. [DOI] [PubMed] [Google Scholar]
- Williamson S., Finucane E., Ellis H., Gamsu H. R. Effect of heat treatment of human milk on absorption of nitrogen, fat, sodium, calcium, and phosphorus by preterm infants. Arch Dis Child. 1978 Jul;53(7):555–563. doi: 10.1136/adc.53.7.555. [DOI] [PMC free article] [PubMed] [Google Scholar]