Comparison of glycolysis and glutaminolysis in Onchocerca volvulus and Brugia pahangi by 13C nuclear magnetic resonance spectroscopy

Mackenzie, Neil E.; Waa, E. A. Van De; Gooley, Paul R.; Williams, Jeffrey F.; Bennett, James L.; Bjorge, S. M.; Baille, Thomas A.; Geary, Timothy G.

doi:10.1017/s0031182000059151

Cited by 17 publications

(1 citation statement)

References 31 publications

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“…The motility parameter is considered to be an indirect measurement of the activity of the parasite's nervous system whereas formazan production measures the activity of various dehydrogenase enzymes in the mitochondria of living cells (Mosmann, 1988). Lactate is one of the predominant excretory products of living filarial worms (MacKenzie et al 1989) and estimation of the lactate content in aliquots of the spent culture medium provides valuable additional information on the metabolic status of female O. volvulus worms (Walter, 1988). These viability indicators have been classified as fast and slow response parameters, depending on their ability to detect either early changes in worm viability, like motility and X T T reduction, or irreversible changes that are associated with worm death, like M T T reduction and lactate output (Comley et al 19896;Strote et al 19906).…”

Section: Discussionmentioning

confidence: 99%

Viability of Onchocerca volvulus in vitro

1993

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The use of a selective schedule of tests to identify a viable population of isolated adult Onchocerca volvulus (Nematoda: Filarioidea) has been investigated in a large worm population. The study was initiated to develop methodology appropriate to test new candidate macrofilaricides for their in vitro activity against O. volvulus. After removal from the host the viability of isolated intact parasites was estimated by assessing the motility indices of male worms, and the colorimetric quantification of the reduction of the bioreducible tetrazolium reagent XTT and lactate output by female worms. Additionally the motility of whole females and the movement of inner organs of female worms were scored quantitatively. These response parameters were used to sort the adult worms into viability groups at the start of the in vitro culture. The adult worms were then observed for 6 days and viability was assessed regularly during the culture period. At the end of the culture period, the reduction of the water-insoluble tetrazolium reagent MTT was used to determine the formazan formed by the entire male and female worms. The response parameters used at the start of the culture proved to be highly predictive for detecting viable and non-viable adult worms. In the group of worms selected as 'viable' around 70% kept their motility and metabolic activity at a high level until the end of the culture compared to the initial level. In contrast, none of the female worms and only 13% of the male worms categorized as 'poorly viable' demonstrated a motility index or metabolic level at the end of the culture period that was comparable to that of the worms in the 'viable' groups. For female worms the lactate output correlated significantly with weight whereas no correlation was seen between MTT reduction and weight.

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Section: Discussionmentioning

confidence: 99%