Nothing to spit at
There’s thirsty. There’s parched. And then there’s clinically dry mouth.
Help may be on the way for the millions of people in the US affected by clinical dry mouth–an uncomfortable feeling of insufficient saliva that can lead to serious health problems. A team of researchers from the University of Texas at San Antonio is studying how silk fibers could help to generate new salivary glands out of stem cells.
Dry mouth is the result of low-producing or non-functioning salivary glands. The condition has a number of causes including medication use, radiation treatment for specific cancers, autoimmune diseases, diabetes, aging and Sjögren’s syndrome–an autoimmune disease diagnosed in 4 million Americans in which the body attacks its own tear ducts and salivary glands.
There isn’t a treatment for chronic dry mouth, and salivary glands have little capacity to renew themselves, highlighting a need for cell-based therapies that grow new tissue and restore gland function.
Salivary glands are part of a healthy mouth.
Silk and Saliva
“The cells had many of the same characteristics as salivary gland cells that grow in the mouth,” says Chih-Ko Yeh the study’s senior author and a professor in comprehensive dentistry who runs a lab focused on salivary gland research. “Salivary gland stem cells are some of the most difficult cells to grow in culture and retain their function.”
Saliva produced in our mouth is critical to good health. In addition to initiating digestion, keeping bits of food off our teeth and preventing oral infection, saliva helps us swallow and speak. Insufficient saliva can lead to bad breath, tooth decay, gum disease and infections in other parts of the body.
The team created a silk framework from purified silk fibers, and populated it with stem cells from rat salivary glands. Then they added a nourishing medium to encourage growth.
“After several weeks in culture, the cells produced a 3D matrix covering the silk scaffolds,” says Yeh. “Silk is a good choice as a scaffolding for the stem cells because it is a natural product, it biodegrades and is flexible and porous. These properties help oxygen and nutrients reach the growing cells easily, and do not lead to inflammation, which has been a problem with other scaffolding materials.”Eventually, the team hopes to use stem cells to regenerate human salivary glands.
Yeh believes that within 10 years we’ll be repairing damaged salivary glands in patients by transfusing stem cells–or engineering artificial salivary gland tissue to replace damaged glands.
“This unique culture system has great potential for future salivary gland research and for the development of new cell-based therapeutics,” explains Yeh.
For those who suffer from chronic dry-mouth this therapy has the potential to improve their quality of life.