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The effect of Giardia lamblia trophozoites on trypsin, chymotrypsin and amylase in vitro

Published online by Cambridge University Press:  06 April 2009

F. Seow ,
P. Katelaris  and
M. Ngu
F. Seow
Affiliation:
Gastroenterology Unit, Repatriation General Hospital, Concord 2139, Sydney, Australia
P. Katelaris
Affiliation:
Gastroenterology Unit, Repatriation General Hospital, Concord 2139, Sydney, Australia
M. Ngu
Affiliation:
Gastroenterology Unit, Repatriation General Hospital, Concord 2139, Sydney, Australia
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Summary

Giardia lamblia localize and multiply in the small intestine and may cause acute or chronic diarrhoea with malabsorption of fat, protein and other nutrients. Abnormal pancreatic function has been documented in giardiasis and trophozoites directly inhibit pancreatic lipase activity in vitro. The aim of this study was to examine the effect of Giardia trophozoites on pancreatic trypsin, chymotrypsin and amylase activity in vitro. Axenically cultured Giardia trophozoites (Portland-1 stock) were incubated with a range of concentrations of trypsin, chymotrypsin and amylase and enzyme activity assayed over time. Tryptic activity was decreased after incubation with Giardia trophozoites. This reduction was time dependent and linear over the incubation period of 2 h. At a trypsin concentration of 18 BAEE units/ml, there was a 35.5±4% reduction in enzyme activity after 2 h compared to controls. The total amount of activity lost was proportional to the initial trypsin concentration up to 185 BAEE units/ml. At this initial concentration, the activity was reduced by 46.5±3 units/ml after 2 h. Above this concentration, little further loss of enzyme activity was seen. To investigate the nature and specificity of this effect, similar experiments were conducted using killed trophozoites and with a related protozoan. Trichomonas vaginalis. No loss of enzyme activity was evident. Media previously incubated for 2 h with trophozoites did not diminish tryptic activity. Trophozoites had no effect on chymotrypsin or amylase activities over the range of concentrations tested. Giardia trophozoites directly diminish pancreatic tryptic activity in vitro, by an active process which appears specific and not mediated via a secretory product. This mechanism may enhance parasite survival in the small intestine by allowing trophozoites to escape destruction by luminal proteases and may also contribute to malabsorption.

Keywords

Giardia lambliatrypsinchymotrypsinamylasepancreatic functionmalabsorption
Type
Research Article
Information
Parasitology , Volume 106 , Issue 3 , April 1993 , pp. 233 - 238
Copyright
Copyright © Cambridge University Press 1993

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References

REFERENCES

Aggarwal, A., Merritt, J. W. Jr. & Nash, T. E. (1989). Cysteine-rich variant surface proteins of Giardia lamblia. Molecular and Biochemical Parasitology 32, 39–48.CrossRefGoogle ScholarPubMed
Birk, Y. (1976). Trypsin and chymotrypsin inhibitors from soybeans. Methods in Enzymology 45, 700–7.CrossRefGoogle ScholarPubMed
Buret, A., Gall, D. G. & Olsen, M. E. (1991). Growth, activities of enzymes in the small intestine and ultrastructure of microvillous border in gerbils infected with Giardia duodenalis. Parasitology Research 77, 109–14.CrossRefGoogle ScholarPubMed
Chawla, L. S., Sehgal, A. K., Broor, S. L., Verma, R. S. & Chhuttani, P. N. (1975) Tryptic activity in the duodenal aspirate following a standard test meal in giardiasis. Scandinavian Journal of Gastroenterology 10, 445–7.CrossRefGoogle ScholarPubMed
Das, S., Reiner, D. S., Zenian, J., Hogan, D. L., Koss, M. A., Wang, C.-S. & Gillin, F. D. (1988). Killing of Giardia lamblia trophozoites by human intestinal fluid in vitro. Journal of Infectious Diseases 157, 1257–60.CrossRefGoogle ScholarPubMed
Erlanger, B. F. N., Kokowsky, W. & Cohen, W. (1961). The preparation and properties of two new chromogenic substrates of trypsin. Archives of Biochemistry 95, 271–8.CrossRefGoogle ScholarPubMed
Gupta, P. K. & Mehta, S. (1973). Giardiasis in children: a study of pancreatic functions. Indian Journal of Medical Research 61, 743–8.Google ScholarPubMed
Halliday, C. E. W., Clark, C. & Farthing, M. J. G. (1988). Giardia–bile salt interaction in vitro and in vivo. Transactions of the Royal Society of Tropical Medicine and Hygiene 82, 428–32.CrossRefGoogle ScholarPubMed
Hartong, W. A., Gourley, W. K. & Arvanitakis, C. (1979). Giardiasis: clnical spectrum and functional–structural abnormalities of the small intestine mucosa. Gastroenterology 77, 61–9.CrossRefGoogle Scholar
Hoskins, L. C., Winawer, S. J., Broitman, S. A., Gottlieb, L. S. & Zamchek, N. (1967). Clinical giardiasis and intestinal malabsorption. Gastroenterology 53, 265–79.CrossRefGoogle Scholar
Katelaris, P. H. & Farthing, M. J. G. (1992). Malabsorption and diarrhoea in giardiasis: a multifactorial process? Gut 33, 295–7.CrossRefGoogle ScholarPubMed
Katelaris, P., Seow, F. & Ngu, M. (1991). The effect of Giardia lamblia on lipolysis in vitro. Parasitology 103, 35–9.CrossRefGoogle ScholarPubMed
Keister, D. B. (1983). Axenic culture of Giardia lamblia in TYI-S-33 medium supplemented with bile. Transactions of the Royal Society of Tropical Medicine and Hygiene 77, 487–8.CrossRefGoogle ScholarPubMed
Lockwood, B. C., North, M. J. & Coombs, G. H. (1984). Trichomonas vaginalis, Trichomonas foetus and Trichomitus batrachorum: comparative proteolytic activity. Experimental Parasitology 58, 245–53.CrossRefGoogle ScholarPubMed
Lockwood, B. C., North, M. J., Scott, K. I., Bremmer, A. F. & Coombs, G. H. (1987). The use of a highly sensitive electrophoretic method to compare the proteinases of trichomonads. Molecular and Biochemical Parasitology 24, 89–95.CrossRefGoogle ScholarPubMed
Nash, T. E., Merritt, J. W. Jr. & Conrad, J. T. (1991). Isolate and epitope variability in susceptibility of Giardia lamblia to intestinal proteases. Infection and Immunity 59, 1334–40.CrossRefGoogle ScholarPubMed
Okada, M., Fuchigami, T., Ri, S., Kohrogi, N. & Omae, T. (1983). The BTPABA pancreatic function test in giardiasis. Postgraduate Medical Journal 59, 79–82.CrossRefGoogle ScholarPubMed
Pappas, P. W. & Read, C. P. (1972). Trypsin inactivation by intact Hymenolepis diminuta. Journal of Parasitology 58, 864–71.CrossRefGoogle Scholar
Rauscher, E., Neumann, U., Schaich, E., von Bulow, S. & Wahlefeld, A. w. (1985). Optimised conditions for determining activity concentrations of alpha amylase in serum, with l,4-alpha-D-4 nitrophenylmalto- heptaoside as substrate. Clinical Chemistry 31, 14.CrossRefGoogle Scholar
Reiner, D. S., Wang, C.-S. & Gillin, F. D. (1986). Human milk kills Giardia lamblia by generating toxic lipolytic products. Journal of Infectious Diseases 154, 825–32.CrossRefGoogle ScholarPubMed
Rhodes, M. D., Marsh, C. L. & Kelley, G. W. (1963). Trypsin and chymotrypsin inhibitors from Ascaris. Experimental Parasitology 13, 266–72.CrossRefGoogle ScholarPubMed
Smith, P. D. (1985). Pathophysiology and immunology of giardiasis. Annual Review of Medicine 36, 295–307.CrossRefGoogle ScholarPubMed
Tandon, B. N., Tandon, R. K., Satpathy, B. K. & Shriniwas, (1977). Mechanism of malabsorption in giardiasis: a study of bacterial flora and bile salt deconjugation in upper jejunum. Gut 18, 176–81.CrossRefGoogle ScholarPubMed
Tomkins, A. M., Drasar, B. S., Bradley, A. K. & Williamson, W. A. (1978). Bacterial colonisation of jejunal mucosa in giardiasis. Transactions of the Royal Society of Tropical Medicine and Hygiene 72, 33–6.CrossRefGoogle ScholarPubMed
Wright, S. G., Tomkins, A. M. & Ridley, D. S. (1977). Giardiasis: clinical and therapeutic aspects. Gut 18, 343–50.CrossRefGoogle ScholarPubMed