Washington, Nov 19 A new study has revealed that protein content of women's saliva changes with advancing age.

According to study's researchers, the discovery could lead to a simple, non-invasive test for better diagnosing and treating certain age-related diseases in women.

These diseases include lupus, Sjögrens syndrome (linked to dry mouth and dry eye), and other immune-related disorders that affect millions of women worldwide.

John Yates and colleagues note that human saliva contains many different proteins involved in digestion, disease fighting, and other functions.

Scientists are seeking ways to use the proteins as molecular "fingerprints" to develop quick diagnostic tests that provide an alternative to the needle sticks currently needed for blood tests.

For that, they conducted a study to determine how normal aging affects these proteins.

The researchers analyzed saliva proteins in healthy women aged 20-30 and 55-65.

They identified 293 proteins differed between the two age groups. Most were involved in the immune system's defences against infection.

Older women had almost twice as many immune-related proteins than younger women.

The results suggest: "It is critical to take into consideration these normal differences in protein expression when searching for clinically relevant, disease specific biomarkers."

The study has been reported in ACS' Journal of Proteome Research, a monthly publication. (ANI)