Dr. Huffman’s research interests are at the intersection of physical activity, inflammation, metabolism, aging, and skeletal muscle. An ultimate goal is to develop evidenced-based exercise interventions for persons with rheumatologic disease, specifically osteoarthritis and rheumatoid arthritis. Additionally, her research aims to improve understanding of the many molecular, inflammatory and metabolic changes within skeletal muscle that that occur with both aging and disease, and how physical activity might be used best to counteract these changes.
Since 2004, Dr. Huffman has worked with Dr. William Kraus focusing on inflammatory and metabolic predictors of skeletal muscle insulin sensitivity and responses to exercise training. Using data from Studies of a Targeted Risk Reduction Intervention through Defined Exercise (STRRIDE), Drs. Huffman, Kraus and others have shown that the degree of insulin resistance corresponds to amounts of circulating branched chain amino acids (1). Additionally, they found that exercise training improves insulin sensitivity in concert with reductions in fatty acids as well as increases in the amino acids, glycine and proline (2). Dr. Huffman’s ongoing collaborations with Dr. W. Kraus involve integration and analysis of multiple data types, including physiologic, genetic, metabolic, and skeletal muscle molecular data. This work will contribute to understanding how multi-systemic responses to exercise training lead to improved cardio-metabolic health.
In collaboration with the Duke Division of Rheumatology, Dr. Huffman is investigating mechanisms of skeletal muscle insulin sensitivity in persons with rheumatoid arthritis (RA). When matched for age, gender, and body mass index, persons with RA were similarly inactive, both groups being almost entirely sedentary. Also, when matched for age, gender, and body mass index, persons with RA has similar levels of insulin resistance, and the greatest determinant of insulin action in those with RA was body composition rather than disease activity. Additional analyses from this investigation are ongoing.
Dr. Huffman works closely with a number of members of the Duke Center for Aging and the Duke Pepper Center including Drs. Virginia Kraus, Harvey Cohen, Miriam Morey, Carl Pieper, Katherine Hall, Gerda Fillenbaum, and Matthew Peterson. This work has focused on inflammatory and metabolic markers of osteoarthritis and functional decline (3,4). As one example, using the Duke Established Populations for Epidemiologic Studies of the Elderly (EPESE), these collaborative efforts found that soluble vascular cellular adhesion molecule (s-VCAM) was related to degree of functional limitation and was a short-term predictor of mortality independent of a number of previously reported markers (5).
Dr. Huffman’s clinical work is performed as part of the Physical Medicine and Rehabilitation Service at the Durham Veterans Affairs Medical Center. Dr. Huffman directs a Musculoskeletal Medicine Clinic for regional musculoskeletal disease and maintains a weekly continuity clinic for persons with rheumatologic disease. In these clinics, Dr. Huffman’s treatment approach emphasizes rehabilitation and exercise training as means to rheumatologic, cardiovascular, and general health. Additionally, these clinics serve as a site for clinic teaching for a number of Internal Medicine Residents, Geriatrics Fellows, and Rheumatology Fellows.