Researchers at the University of Ulster in Ireland have uncovered a vital weapon in the fight against killer diseases such as cancer and heart disease - frog venom.The team, headed by Professor Chris Shaw, has discovered that molecules called peptides, secreted by rain forest frogs to ward off predators, have the potential to:
* Dramatically reduce high blood pressure;
* Stop blood clotting, an effective tool in the fight against Deep Vein Thrombosis and heart disease;
* Tackle conditions that are resistant to treatment by conventional antibiotics;
* Make crops resistant to insect attack;
* Help tackle cancer tumors and leukemia and protect bone marrow against damage during chemotherapy.
Professor Shaw, from the School of Biomedical Sciences at the University’s Coleraine campus, said: “Biological warfare has been going on in the rain forest for millions of years as each organism living there has fought for its survival. I believe that we can put that biological weaponry to use for the good of humankind in the ultimate defeat of those diseases which have thus far remained intractable”.
The Ulster researchers have been investigating the medical properties of rain forest frog venom for several years. They use very mild electrical stimulation to encourage the frogs to secrete their venom, which is then broken down into its component parts in the laboratory.
After screening the venom, the researchers are able to explore its medical potential, if any.
* Peptides obtained from the Giant Mexican Leaf Frog have been found to reduce blood pressure by 50% when administered in very low doses under laboratory conditions. This unlocks the potential for new drugs to help people suffering from high blood pressure.
The same frog also produces a peptide which stops blood from clotting, opening the way for new treatments for Deep Vein Thrombosis -- the so-called "economy class syndrome" recently highlighted when passengers on long haul aircraft flights suffered lethal blood clots and heart disease.
* The African Running Frog produces a venom which paralyzes giant insects which prey on it. Peptides from the venom could be incorporated into food crops or crops such as cotton to prevent insect attack without the use of pesticides.
* A Tree Frog from Australia has peptides which are effective in tackling conditions which are resistant to conventional antibiotics, an increasingly alarming problem in medicine. The peptides work in a novel way, embedding themselves in the membrane of the bacteria and effectively bursting the cell. Bacteria cannot become resistant to them.
* Molecules from a North American Pond Frog are similar to messenger molecules in the human body which are known to stimulate or inhibit the growth of cancer tumors. This could lead to the development of treatments for tackling tumors. Other potential uses are in the fight against leukemia and in reducing the damage to bone marrow from chemotherapy treatment.
Professor Shaw said: “This could be a giant leap forward for medicine. We can use the biological weaponry evolved in the frog’s venom to fight against cancer, heart disease and neurodegenerative diseases. I believe the cure for these exist in the rain forest in the molecules that have evolved over millions of years.”
Much of Professor Shaw’s field research was carried out in the rainforests of China in association with researchers from the University of Fuzhou in China. Professor Shaw will be returning to the rainforests shortly in search of new specimens.
20-Sep-2001