Harmful Algal Blooms and Cystic Fibrosis: A Surprising Connection

Daniel C. Baden, Ph.D.
University of North Carolina at Wilmington
P01ES10594

Background: The harmful algal bloom known as Florida red tide is caused by a dinoflagellate organism known as Karenia brevis. These blooms can cause respiratory distress in exposed people and usually occur during the summer when the potential for exposure is higher. Toxins produced by the organism cause upper and lower airway symptoms in normal individuals and more severe effects in people with a preexisting airway disease such as asthma. NIEHS-supported researchers at the University of North Carolina at Wilmington conducting research on the toxins, recently made a surprising discovery linking Florida red tide antitoxins to the treatment of cystic fibrosis.

Cystic fibrosis (CF) is a genetic disease affecting approximately 30,000 children and adults in the United States. A defective gene causes the body to produce abnormally thick, sticky mucus that clogs the lungs and can lead to life-threatening lung infections. Every year about 1000 people are diagnosed with the disease in the U.S. Life expectancy is generally shorter for people with the disease although medical advancements have prolonged life for many.

Advance: While trying to determine if the respiratory effects caused by exposure to the toxins could be prevented, these researchers discovered a natural antitoxin produced by the algae and a synthetic antitoxin. In studies conducted in laboratory animals, this team noticed that the antitoxins acted in much the same way as drugs used to treat cystic fibrosis. The antitoxins sped up the clearance of mucus from the lungs. The researchers suspect that the antitoxins work by increasing the movement of cilia, tiny hair-like structures that line airways, and also by thinning the mucus.

Implications: Other studies in laboratory animals demonstrated that the newly discovered compounds are effective at much lower doses than current therapies. Also important is that there were no side effects from the treatments. Additional research will be necessary to confirm these results; however, the antitoxins may lead to better, more effective treatments for cystic fibrosis and other similar lung diseases.

Citation: Abraham WM, Bourdelais AJ, Sabater JR, Ahmed A, Lee TA, Serebriakov I, Baden DG. Airway responses to aerosolized brevetoxins in an animal model of asthma. Am J Respir Crit Care Med. 2005 Jan 1;171(1):26-34. Epub 2004 Sep 24.