Submitted to: Planta Medica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/22/2001
Publication Date: N/A
Interpretive Summary: Cryptosporidium parvum is an intestinal protozoan parasite that causes diarrheal disease in calves. This disease is costly to dairy and beef producers and the disease can also spread to humans. Unfortunately, there are no effective drug treatments available for this parasite. A group of compounds, called aurones, have activity against another intracellular protozoan parasite, Leishmanian sp.. In the present study, it was determined that aurones are effective at inhibiting the in vitro growth of Cryptosporidium. These compounds also diminished Cryptosporidium infection of immune deficient mice. Further study of these compounds may lead to ways to treat Cryptosporidium infection in calves, thus reducing economic losses to producers and reducing the risk of human disease through exposure to sick calves.
Technical Abstract: A series of aurones and 4-methoxy-alpha-pyrones from natural sources were tested for their potential to inhibit growth of Cryptosporidium parvum in vitro and in vivo. The compounds were active in vitro at concentrations form 25 to 100 uM. Ten (10) of 19 compounds tested were aurones that exhibited greater than 90% inhibitin of growth in vitro with moderate or no toxicity. The most active derivative was 3', 4', 6-Trihydroxy-2- [phenylmethylene]-3(2H)-benzofuranone which, at 100 uM, inhibited growth of C. parvum in vitro by 98%, and in mice reduced the infectivity score within the caecum to 0.49 (0.30) of experimentally infected mice. For all compounds tested in vivo, no acute or chronic toxicity was observed. The structure-activity relationships of aurones, auronols, and alpha-pyrones is discussed.