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Electron microscopical study to assess the in vitro effects of the synthetic trioxolane OZ78 against the liver fluke, Fasciola hepatica

Published online by Cambridge University Press:  07 August 2009

L. HALFERTY ,
J. F. O'NEILL ,
G. P. BRENNAN ,
J. KEISER  and
I. FAIRWEATHER
L. HALFERTY
Affiliation:
Parasite Therapeutics Research Group, School of Biological Sciences, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland
J. F. O'NEILL
Affiliation:
Parasite Therapeutics Research Group, School of Biological Sciences, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland
G. P. BRENNAN
Affiliation:
Parasite Therapeutics Research Group, School of Biological Sciences, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland
J. KEISER
Affiliation:
Department of Medical Parasitology and Infection Biology, Swiss Tropical Institute, P.O. Box, CH-4002 Basel, Switzerland
I. FAIRWEATHER*
Affiliation:
Parasite Therapeutics Research Group, School of Biological Sciences, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland
*
*Corresponding author: School of Biological Sciences, The Queen's University of Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland. Tel: +44 28 90972298. Fax: +44 28 90975877. E-mail: [email protected]
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Summary

Adult Fasciola hepatica were incubated for 48 h in vitro in the synthetic peroxide, OZ78 at a concentration of 100 μg/ml and then prepared for scanning and transmission electron microscopy. There was limited disruption to the external fluke surface, with only slight swelling and blebbing of the interspinal tegument in the midbody and ventral tail regions. By contrast, significant disruption was observed to the ultrastructure of the tegument and subtegumental tissues. There was severe swelling of the basal infolds in the tegumental syncytium and the flooding spread internally to affect the subtegumental tissues. In the tegumental system, there was swelling of the cisternae of granular endoplasmic reticulum and of the mitochondria, with the latter showing signs of breaking down. Autophagic vacuoles and lipid droplets were present and the synthesis of tegumental secretory bodies was much reduced. The gastrodermal cells were severely affected, with swelling and degeneration of the mitochondria and the presence of autophagic vacuoles and lipid droplets. The granular endoplasmic reticulum was swollen and vesiculated and the cells contained few secretory bodies. Both the vitelline and testis follicles showed evidence of extensive cellular disruption and degeneration. This study confirms previous data indicating the potential flukicidal activity of OZ78.

Keywords

Fasciola hepaticaliver flukesynthetic artemisinin derivativeOZ78scanning electron microscopytransmission electron microscopyin vitro culture
Type
Research Article
Information
Parasitology , Volume 136 , Issue 11 , September 2009 , pp. 1325 - 1337
Copyright
Copyright © Cambridge University Press 2009

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