Regulation of schistosome egg production by HMG CoA reductase
Hydroxymethylglutaryl coenzyme A reductase (HMG CoA reductase) catalyzes the conversion of HMG CoA to mevalonate in the synthesis of steroids, isoprenoids and terpenes. Mevinolin, an inhibitor of this enzyme, decreased egg production in Schistosoma mansoni during in vitro incubations. This was associated with a reduction in the incorporation of /sup 14/C-acetate into polyisoprenoids and a reduction in the formation of a lipid-linked oligosaccharide. In vivo, mevinolin in daily doses of 50 mg/kg (p.o., from days 30-48 post-infection) caused no change in gross liver pathology in S. mansoni infected mice. However, when parasites exposed to mevinolin or its vehicle in vivo were cultured in vitro, worms from mevinolin-treated mice produced six times more eggs than control parasites. When infected mice were dosed with 250 mg/kg mevinolin daily (p.o., from days 35-45 post-infection), liver pathology was reduced in comparison to control mice. Thus, during in vivo exposure to a high dose of the drug egg production is decreased, while at a lower dose it appears unaffected until the parasites are cultured in a drug-free in vitro system wherein egg production is stimulated to extraordinarily high levels. It may be that at low doses mevinolin, by inhibiting the enzyme, is blocking the formation of a product (such as an isoprenoid) which normally acts to down-regulate enzyme synthesis, resulting in enzyme induction. Induction of HMG CoA reductase is then expressed as increased egg production when the worms are removed from the drug. These data suggest that HMG CoA reductase plays a role in schistosome egg production.
- Research Organization:
- Michigan State Univ., East Lansing
- OSTI ID:
- 6936768
- Report Number(s):
- CONF-8604222-; TRN: 87-008618
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
- Country of Publication:
- United States
- Language:
- English
Similar Records
Dynamics of glutathione regulation in Schistosoma mansoni: correlations with the acute effects of oltipraz
Murine eosinophils labeled with indium-111 oxine: localization to delayed hypersensitivity reactions against a schistosomal antigen and to lymphokine in vivo
Related Subjects
OXIDOREDUCTASES
ENZYME ACTIVITY
SCHISTOSOMA
INFECTIVITY
CARBON 14 COMPOUNDS
EGGS
ENZYME INHIBITORS
MICE
TRACER TECHNIQUES
ANIMALS
ENZYMES
HELMINTHS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
PLATYHELMINTHS
RODENTS
TREMATODES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques