In the ongoing search to find medications for breathing disorders like sleep apnea and asthma, two teams of researchers based at the University of Chicago have received grants from the National Institutes of Health for the development of possible solutions. One team, lead by Nanduri Prabhakar, PhD, will focus on researching and perfecting a possible drug to prevent sleep-disordered breathing. The other team, lead by Julian Solway, MD, the Walter L. Palmer Distinguished Service professor of medicine and pediatrics, will focus on the development of a potential drug to control severe asthma.
Each team will receive funding that amounts to roughly $1.7 million annually for up to five years. Both teams will collaborate with other medical professionals based at universities around the nation during every stage of the development and clinical trials. Whether or not this will lead to the production of effective drugs that may help people with sleep apnea or asthma is uncertain at this time.
A Hopeful Outlook
For almost 20 years, Dr. Prabhakar and his colleagues have conducted studies focusing on chemical signals released by the carotid bodies, small clusters of cells found in the carotid artery on either side of the throat. These cell clusters are the primary sensors of blood oxygen levels, and are extremely sensitive to changes in these levels. When blood oxygen levels drop, the carotid bodies send signals to the brainstem neurons to prompt the next breath. In people with sleep apnea, these cell clusters become hypersensitive to oxygen level fluctuations and fail to maintain a steady respiration rate.
One factor Prabhakar and colleagues found that contributed to this malfunction of the carotid bodies was an overactivation of an enzyme produced by the body. This enzyme, known as cystathionine-gamma-lyase (CSE), increases the production of hydrogen sulfide. Overstimulation of the system appeared to make the carotid body hypersensitive to certain signals, but ineffective at initiating breathing.
Based on their findings, the team produced a molecule to target CSE and inhibit activity. Their early tests found that their molecule could normalize sleep in a rodent population model of sleep apnea. From the molecule they created a compound that could be taken by mouth. “Our mice typically have about 60 apneas per hour,” Prabhakar said. “Thirty milligrams of our compound produces a marked reduction in apneas. At 90 milligrams they have very few at all.”
Using the funding from the National Institutes of Health, Dr. Prabhakar and his team hope to increase the efficiency, potency, and safety of their compound. Once they have maximized its efficiency and safety, the experimental drug will be tested in clinical trials.
Waiting Takes Patience
Currently, there are no effective drugs to treat sleep apnea. A range of other non-surgical treatment options including CPAP and oral appliances have helped people suffering from sleep apnea. A number of drugs have been tested in the past, but have not shown significant differences during clinical trials. These results may leave people feeling hopeless about future drug testing, but it is important to remember that the successful production of medication takes time.
Only time will tell whether or not Dr. Prabhakar and his team will see success with their experimental drug to treat sleep apnea, but this is how medicine advances. Learning from the clinical trials that came before them, it is possible that Dr. Prabhakar’s team will successfully create a drug to help sleep apnea patients sleep soundly. Success could reduce or eliminate health risks such as heart failure, diabetes, and depression.
Interested in learning more about effective, drug-free treatment of sleep apnea while we wait to see how clinical trials play out? Please call (303) 691-0267 for an appointment at the TMJ Therapy & Sleep Center of Colorado in Denver.