December 21, 2021

Eminent Mentor and Researcher – Charles A. O’Brien, Ph.D.

Charles A. O'Brien, Ph.D. 

Charles O’Brien, Ph.D., is the Director of the Center for Musculoskeletal Disease Research and from 2005 to 2021 was the Director of the Genetic Models Core which serves UAMS, ACRI, and the CAVHS.

Beyond his leadership roles in research, he is also a Professor of Medicine in the UAMS Division of Endocrinology and the Department of Orthopaedic Surgery and is a CAVHS Research Scientist.


His research focuses on understanding the cellular and molecular mechanisms that control bone remodeling in health and disease, particularly involving glucocorticoid excess and aging through the study of bone cells known as osteocytes.

In addition to the years of research dedicated to musculoskeletal studies, Dr. O’Brien mentors junior faculty, helping investigators develop their research and acquire federal funding for their studies. To support these efforts, in 2018, P20 funding from the NIH/NIGMS enabled Dr. O’Brien and his colleagues to establish the Center for Musculoskeletal Research, of which he is now the director.

Since 1993, the focus of Dr. O’Brien’s laboratory has been to uncover the molecular mechanisms that lead to osteoporosis. Other investigators at the center also focus on osteoporosis but other topics as well, including osteoarthritis, bone-related cancers, and joint repair. The bulk of that research involves animal modeling with genetically-modified rodents that help answer specific questions about the musculoskeletal system.

Investigators in the Center examine different causes of bone loss and degeneration—estrogen deficiency, aging, and glucocorticoid excess. Those three conditions are responsible for the bulk of osteoporosis in the world. And the Center for Musculoskeletal Disease Research studies animal models involving each of these.

One of the most recognized findings from the work of Dr. O’Brien and his colleagues has been the identification of osteocytes as an important orchestrator of bone remodeling. The results of their studies demonstrated that this particular cell type is integral to how bone responds to changes in hormone levels or loading. More specifically, they are a source of a protein that stimulates bone resorption.

While Dr. O’Brien still pursues his own research, his time is much more focused on guiding the junior faculty to become successful scientists. The Center, however, extends beyond the Division of Endocrinology and so there is an instrumental collaboration between basic scientists and clinicians that helps each group develop insights based on the shared communication and research efforts.