15 December 2005

Virgin Islands' sponges may assist in the treatment of human disease

The coral reefs of the Caribbean are showing potential as the next great frontier for drug researchers seeking to cure cancer, malaria and other deadly diseases.

This summer, a green sponge collected in St. Thomas' Brewers Bay yielded an extract that could one day be used to treat leishmaniasis, a disfiguring and often deadly disease of the developing world.

Researchers elsewhere in the Caribbean have uncovered a cancer-fighting substance in red algae and an anti-malarial compound in another marine sponge.

While this field of research is still in its infancy, scientists believe that tropical waters may be a treasure trove of lifesaving medicines. Because of its island location in the Caribbean, the University of the Virgin Islands is positioned to play a key role in finding useful marine organisms.

As a relatively small institution, UVI has limited research facilities, but its natural resources are unmatched. The solution -Â at least for now - is partnerships with larger universities.

"It's perfect that we are here surrounded by the tropical reefs, but we do have to work with research organizations in the states," said Jennifer Carroll, a UVI assistant professor of chemistry who specializes in marine natural products.

Carroll said in an interview last week that she began working in 2004 with two scientists from the University of Mississippi - Professor Deborah Gochfield and Professor Marc Slattery. The university is home to the federally funded National Center for Natural Products Research, which has state-of-the-art facilities for studying potential new drugs.

Under the arrangement, UVI handles the first steps of collecting and processing samples. Through the partnership, Mississippi researchers later test the extracts for activity against diseases including cancer and HIV.

Gochfield said in a telephone interview this week that the Virgin Islands coral reefs "hold great potential."

"The Virgin Islands is perfectly situated right at the center of the Caribbean, so you get an incredible diversity of species," Gochfield said. "We're lucky to have UVI as a partner."

The tropical waters are home to thousands of species, many of which secrete chemicals to protect themselves from predators, pathogens and competitors. As those compounds are discovered, their uses - particularly what role they could play in human health - are an intriguing puzzle.

The marine natural products field is just taking off because collecting samples became possible only in the mid-1900s with the invention of scuba - self-contained underwater breathing apparatus.

To obtain raw materials, the scientists scuba dive for sponges, soft corals and tunicates. To minimize their impact on reef ecosystems, they take only fist-sized samples, and they don't collect hard corals or protected species. The samples are processed into crude extracts, which must be refined through a long and painstaking process.

"We're hoping to find a new molecule or a synergistic combination of molecules that can be patented," Carroll said. From her past research, Carroll holds a patent to a molecule from a South American sea sponge that could one day be useful in organ transplantation.

UVI undergraduate student Jeffrey Purcell has been studying marine natural products under Carroll's supervision, and this summer he was invited to do work at Mississippi.

His job was to refine extracts of a green encrusting marine sponge collected in Brewers Bay.

While many of his classmates were lounging on the beach, Purcell was in Mississippi spending long hours in the lab. All his hard work paid off, however, when three samples showed activity against leishmaniasis - a disease that has developed resistance to many existing medicines.

Purcell said in an interview last week that learning the result was a high point of his undergraduate experience. "It was an amazing feeling," he said. "This work is needed, and it's not really a priority in mainstream research because it affects the Third World."

Leishmaniasis, caused by protozoans and transmitted through the bite of a sand fly, afflicts more than 2 million people a year, the majority of them in India. The disease causes crater-like scars, and certain forms are fatal.

For his work, Purcell won a "Best Poster" award when he presented his findings at the Annual Biomedical Research Conference for Minority Students, which was held in November in Atlanta.

This research is just the beginning of drug development, a long and expensive process involving laboratory tests, trials in animals and then in humans, testing for safety and effectiveness, government approval and finally production as a commercial drug.

Scientists say bringing a new drug to market can cost $1 billion, and the high cost means that development is usually sponsored by a pharmaceutical company or the government.

"It takes 20 or 30 years to go from a discovery like Jeffrey's to a product that is marketable and usable in humans," Carroll said.

Many new drugs are0 launched at the University of Mississippi, which has the nation's only center devoted to studying natural products. Much research has focused on plants, but marine products research is gathering momentum with the recent creation of the National Institute for Undersea Science and Technology.

Recent discoveries by Mississippi researchers in Caribbean waters have included a compound in red algae that shows anti-cancer activity and a species of sponge that shows activity against malaria.

Purcell is considering applying to Mississippi for graduate school.

Meanwhile, UVI is building its own research capacity. The territory is receiving a total of $4.5 million over four years from the National Science Foundation for the Virgin Islands Experimental Program to Stimulate Competitive Research, or EPSCoR. The grant program is aimed at promoting scientific progress by supporting innovative research and by improving the research infrastructure. UVI is using the funding to develop an international center of excellence in the study of coral reef ecosystems.

Thus far, EPSCoR has funded marine laboratory improvements and has paid for a research dive boat, based at UVI's MacLean Marine Science Center, which Carroll will use in collecting samples.

Carroll's research is among projects that are being supported by the EPSCoR funding.

Carroll said her dream is to perform drug discovery research without having to leave the U.S. Virgin Islands.

Next year, she plans to submit a grant proposal that would enable UVI to purchase a Nuclear Magnetic Resonance Spectrometer, equipment used to identify the structure of molecules. "Ultimately, I want to do the high-level research here," she said.

- Contact Tanya Mannes at 774-8772 ext. 317 or e-mail tmannes@dailynews.vi.

Source: www.virginislandsdailynews.com


Post a Comment

<< Home