Fight parasites with compounds in worms

CORNELL (US) — A class of molecules used by all nematodes could lead to news ways to treat parasites that infects humans, animals, and crops.

Hookworms, whipworms, Ascaris, Guinea worms, and trichina worms are just a few parasitic nematodes that infect some 2 billion people. Researchers report that nematodes use the newly discovered class of small molecules to signal such processes as growing, developing, mating, and moving toward or away from an area.

“All of these nematodes speak the same chemical language,” through the use of compounds called ascarosides, says study co-author Frank Schroeder, a research scientist at the Boyce Thompson Institute for Plant Research and adjunct assistant professor at Cornell University.


The study, published online in the journal Current Biology, was led by Stephan von Reuss, a postdoctoral associate in Schroeder’s lab, and Andrea Choe, a postdoctoral scholar in the lab of co-author Paul Sternberg, a biologist at the California Institute of Technology.

Since nematodes are the only known organisms to use ascarosides, “we don’t have to be afraid of interfering with similar biochemistry in animals, plants, or humans,” Schroeder says, as researchers seek to identify species-specific ascaroside molecules that may enable novel approaches to deter or disrupt the survival or reproduction of parasitic worms.

Researchers in Schroeder’s lab have already filed for three patents, one that covers the structures of various ascarosides, one that covers ascarosides for use as agents to protect plants, and one that makes claims to how to use the compounds to treat or prevent human disease.

The researchers first discovered ascarosides as a signaling molecule in C. elegans, a nematode used as a model organism to study cell, developmental, and nervous system biology, as well as human aging and diabetes.

“We then thought, if C. elegans uses this chemical language, perhaps other nematodes do too,” Schroeder says.

Proving their hunch, the researchers found ascarosides in the secretions of every nematode they examined, and a few subsequent experiments showed that the small compounds also acted as signaling molecules in the species’ they investigated.

The ascaroside communication system in nematodes resembles communication modes in bacteria where very different bacteria species can communicate using a conserved chemical code, Schroeder explains.

The study was funded by the National Institutes of Health and the Howard Hughes Medical Institute.

More news from Cornell University: