A compound in the curry spice turmeric appears to correct the cystic fibrosis defect in mice, report Canadian scientists, demonstrating the potential for treating the disease in humans.
The study is the latest to highlight the medicinal value of curcumin, which gives turmeric or Curcuma longa, its yellow colour and bright taste.
Previous trials suggest that the spice could prevent the onset of alcoholic liver disease, may slow down the blood cancer multiple myeloma and multiple sclerosis, and could be an inexpensive, well-tolerated, treatment for inflammatory bowel disease.
While the current trial, and most of the earlier studies, only tested cells in a lab, researchers believe that there is enough evidence to progress to a human clinical trial.
Cystic fibrosis is a fatal genetic disease affecting around 30,000 people in the US and another 30,000 around the world. One person in 25 carries the defective gene that causes the disease in which thick mucous clogs the lungs and the pancreas due to problems with the secretion of ions and fluid by cells of the airways and gastrointestinal tract. Normal secretion depends upon the function of a protein called CFTR (cystic fibrosis transmembrane conductance regulator), which was discovered at the Toronto-based Hospital for Sick Children in 1989.
Mutations in the gene encoding CFTR are responsible for cystic fibrosis. In the most common form of cystic fibrosis, the CFTR protein is trapped inside the cell, and is therefore unable to carry out its proper function at the cell surface.
Marie Egan and Michael Caplan from Yale University School of Medicine, and Gergely Lukacs from Sick Kids report in today's issue of Science (pp600-602) that curcumin treatment in a mouse model can release the mutant CFTR protein from this inappropriate compartment inside the cell and allow it to reach its proper destination, where it is able to function.
"We were able to prove at the cellular level what the Yale group observed in the mouse model of the disease," said Dr Lukacs. "After having received curcumin treatment, mice with the genetic defect that causes CF survived at a rate almost equal to normal mice. The CFTR protein also functioned normally in the cells lining the nose and rectum, which are areas of the body affected by cystic fibrosis."
Dr Caplan added: "In the next phase of this research, we will work to determine precisely how curcumin is achieving these effects and to optimize its potential as a possible drug."
Cystic Fibrosis Foundation Therapeutics, the nonprofit drug discovery and development affiliate of the Cystic Fibrosis Foundation charity, is currently working with Seer Pharmaceuticals on a Phase I clinical trial of curcumin to assess safety and dosage parameters in humans.
The small trial will be conducted in four to six sites and will include approximately 25 patients.