Heart drug derails algal toxin - Biomedicine - cholestyramine - Brief Article

Science News, June 7, 2003

A drug for treating high cholesterol might someday find use relieving the debilitating symptoms of poisoning from some algal toxins, animal data suggest.

Algal toxins accumulate in fish and shellfish, which, when eaten, can cause symptoms ranging from muscular weakness and pain to death. After heating anecdotes of physicians easing symptoms of such poisonings with the cholesterol-lowering drug cholestyramine, John S. Ramsdell of the National Oceanic and Atmospheric Administration in Charleston, S.C., decided to test it in mice.

He laced the rodents' food with the drug for a week and then exposed the animals to brevetoxin, the poison made by Florida's red tide algae (SN: 11/30/02, p. 344). Mice usually respond to this toxin with a quick drop in body temperature. However, temperatures remained normal in animals treated with cholestyramine. Ramsdell reported the finding in April at Experimental Biology 2003, in San Diego.

Although he initially suspected the drug was removing the toxin from the animals' blood, subsequent tests showed that blood brevetoxin was just as high in animals that received cholestyramine as in those that didn't. Those tests used the first diagnostic blood test for brevetoxin, which Ramsdell and his colleagues describe in an upcoming Environmental Health Perspectives.

Now, the team is testing an alternative hypothesis for cholestyramine's efficacy. Lowering cholesterol reduces the body's production of cholesterol-carrying molecules known as low-density lipoproteins. Ramsdell suspects those same molecules are responsible for transporting the fat-soluble brevetoxin from the blood into tissues where the poison can do its worst.