However, a series of papers from the Kelly lab has shown that several other treatment approaches hold promise.
The Promise of a New Treatment Approach
In a paper published in PLoS Biology in 2008, the lab found that the prescription drugs diltiazem and verapamil were effective in restoring partial cellular folding, trafficking, and function to mutant enzymes responsible for three lysosomal storage disorders, including Gaucher's disease.
The scientists suspected that the drugs enhanced the interaction between the mutant lysosomal enzyme and the machinery of the cell that folds proteins, the so-called "chaperones" (helper proteins). Enhanced chaperone function, the scientists believed, might enhance the extent of mutant enzyme folding in the endoplasmic reticulum, allowing more of the mutant enzymes to engage the trafficking pathway that transports them to the lysosome. Even though the mutant enzymes are not completely normal, they exhibit sufficient function (greater than 10 percent) to improve the lysosomal storage phenomenon that causes these maladies.
But to make a more persuasive case for expensive clinical trials, the scientists wanted to understand the mechanism(s) by which the drugs were altering the cellular chaperones. The new study helps answer this question.
Using biochemical, pharmacologic, and siRNA techniques, the scientists examined the hypothesis that these drugs increased calcium levels in the endoplasmic reticulum post-translationally enhancing the calcium-regulated chaperones.
"We interrogated the importance of two calcium efflux channels and one pump
|Contact: Keith McKeown|
Scripps Research Institute