By Cristy Lytal

DNA (Creative Commons image by Christoph Bock/Max Planck Institute for Informatics)

A new study in Aging Cell describes how a key protein, called Signal Transducer and Activator of Transcription 3 (STAT3), might turn back the clock on aging cartilage that leads to osteoarthritis.

“STAT3 performs an astonishing repertoire of roles in development and regeneration, as well as inflammatory disease and cancer. In this study, we found an innovative chemical approach for reversing aging of joint-forming cells in a clinically relevant manner, because this intervention is simple and fully controlled,” said the study’s co-corresponding author Denis Evseenko, who is a Professor of Orthopaedic Surgery, and Stem Cell Biology and Regenerative Medicine at USC, and holds the J. Harold and Edna LaBriola Chair in Genetic Orthopedic Research.

“We wanted to understand the role of STAT3 in cartilage cells during embryonic development as well as in the context of osteoarthritis,” said co-corresponding author Steve Horvath, a Professor of Human Genetics and Biostatstics at UCLA.

To accomplish this, first authors Arijita Sarkar, Nancy Q. Liu and their colleagues at USC and UCLA performed a series of experiments to uncover how STAT3 turns genes on and off through a process known as epigenetic regulation. Specifically, the team identified patterns of epigenetic regulation that correlate with the age of cartilage cells. These correlations served as the basis for creating what the researchers dubbed an “epigenetic clock” for cartilage cells. (…Learn More)