Timothy M. Griffin, Ph.D.
Associate Member
Aging & Metabolism Research Program
Research Biologist, Oklahoma City VA Health Care System Adjunct Associate Professor, Department of Physiology and Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center
Member, Reynolds Oklahoma Center on Aging and Oklahoma Center for Neuroscience, University of Oklahoma Health Sciences Center
My 101
When we imagine retirement, we often picture ourselves traveling to new lands and getting back in touch with nature through gardening or taking hikes. We take for granted that our bodies will carry us forward into these hard-earned dreams. However, for over 32 million Americans, these dreams may be put on hold due to joint pain and stiffness caused by osteoarthritis. Osteoarthritis is the most common form of arthritis, and it’s the leading cause of disability in the U.S. My lab is studying how this disease begins and how we can treat people already suffering from it.
The chances of developing osteoarthritis increase as we age, put on weight, or injure our joints. Although conventional wisdom holds that increased pressure on joints from carrying excess weight causes osteoarthritis, this is far from a complete answer. Recent discoveries suggest that fat itself is a critical mediator of the disease. Fat is not just storing excess energy from food. Rather, fat acts like an organ by releasing molecules that affect how the body functions. When the body has too much fat, it can release molecules that activate immune cells and cause inflammation.
My lab is studying how obesity alters the metabolic machinery of tissues and cells within the joint. We believe that excess fat causes metabolic changes that promote joint inflammation, tissue damage, and ultimately joint pain. Luckily, these negative effects of excess fat can be reversed through exercise, even without weight loss. Many studies show that staying active is the best way to reduce osteoarthritis pain. Therefore, we're also studying how exercise breaks the cycle of metabolic inflammation and pain to develop new treatment options for people to live more active lives free from limitations. By focusing on the metabolic basis of osteoarthritis, we expect to open up new treatment strategies by painting a more complete picture of this costly disease.
Research
Osteoarthritis is a disease characterized by cartilage destruction and abnormal bone growth resulting in joint pain and severe disability. It is the primary cause of disability in the United States, and it contributes significantly to reductions in health that occur with aging. Although osteoarthritis is often considered an inevitable consequence of aging, numerous genetic and environment risk factors have been identified that mediate its occurrence and severity. One of the most significant and modifiable risk factors is obesity.
Our laboratory uses integrative and interdisciplinary approaches to study how obesity dysregulates biomechanical, inflammatory, and metabolic processes that are associated with the development of osteoarthritis. We are seeking to determine how dietary fats, adipokines (e.g., leptin), and cyclic joint loading regulate articular cartilage homeostasis via effects on chondrocyte mitochondrial function and free radical biology. We are particularly interested in the role of sirtuins (e.g., Sirt3) as regulators of cellular metabolism and oxidative stress responses that help maintain chondrocyte function during aging, obesity, and injury. In addition, we are investigating how intra-articular adipose tissue modulates joint inflammation by altering the metabolic environment of the joint.
We are also interested in understanding how physical activity interacts with obesity-related phenotypes to regulate these processes in healthy and diseased tissue. Therefore, we use a variety of models spanning multiple levels of organization (e.g., cell, tissue, and animal) to study the effect of voluntary exercise (in vivo) and controlled biomechanical loading regimes (in vitro) on inflammatory, metabolic, and anti-oxidant processes in cartilage.
By studying the interaction of diet and physical activity (i.e., two modifiable risk factors for obesity) during aging, we hope to reveal novel pathways that regulate cartilage matrix homeostasis. Furthermore, by examining behavioral changes in our animal models that are associated with motor function and pain, we emphasize clinically relevant outcome measures so that we can better translate our finding to patients. These studies provide a basis for examining how therapeutic interventions that target inflammatory, metabolic, or oxidative processes affect joint-specific pathophysiology and functional outcomes.
Brief CV
Education
B.A., Harvard University, Cambridge, MA, 1996
Ph.D., University of California, Berkeley, CA, 2002
Postdoc, Duke University Medical Center, Durham, NC, 2002–2007
Honors and Awards
2020 Merrick Award for Outstanding Medical Research
2020 Health Care Hero, The Journal Record
2018 Arthritis Foundation Medical Honoree, OKC Arthritis Walk
2016 Fred Jones Award for Scientific Achievement, Oklahoma Medical Research Foundation
2010 Top 10 Arthritis Advances, Arthritis Foundation
2010 Melba M. O’Connell Memorial Fellow, Arthritis National Research Foundation
2007 Outstanding Postdoc Award, Duke University
2007 Young Investigator Award, Osteoarthritis Research Society International (OARSI) World Congress on Osteoarthritis
2007 Hulda Irene Duggan Arthritis Investigator Award, Arthritis Foundation
2004 NIH Ruth L. Kirschstein National Research Service Award (NIAMS)
2003 New Investigator Award, American Physiological Society
Professional Activities
2019 - present: Associate Editor, Osteoarthritis and Cartilage
2017 - present: Ad hoc reviewer, SBSR Study Section (NIH)
2016 - 2019: Editorial Board Member, Osteoarthritis and Cartilage
2015: Section Leader (OA Laboratory Grants), Arthritis Foundation's Delivering on Discovery Peer Review
2015-present: Member, NIH NIAMS Biospecimen Review and Allocation Committee for the Osteoarthritis Initiative
2014-2016: Co-chair, Cartilage, Synovium & Osteoarthritis Topic Committee, Orthopaedic Research Society
2013-2016: Advisory Editor, Arthritis & Rheumatology
2013: Invited Participant, NIH NIAMS Roundtable on OA and Inflammation
Memberships
American Physiological Society
Orthopaedic Research Society
Osteoarthritis Research Society International
Joined OMRF Scientific Staff in 2008.
Publications
Recent Publications
Griffin TM, Lories RJ. Cracking the code on the innate immune program in OA. Osteoarthritis Cartilage, 2020 April, PMID: 32278072
Sun C, Sakashita H, Kim J, Tang Z, Upchurch GM, Yao L, Berry WL, Griffin TM, Olson LE. Mosaic Mutant Analysis Identifies PDGFRα/PDGFRβ as Negative Regulators of Adipogenesis. Cell Stem Cell, 2020 March, PMID: 32229310, PMCID: PMC7214206
Griffin TM, Batushansky A, Hudson J, Lopes EBP. Correlation network analysis shows divergent effects of a long-term, high-fat diet and exercise on early stage osteoarthritis phenotypes in mice. J Sport Health Sci 9:119-131, 2020 March, PMID: 32099720, PMCID: PMC7031811
Selected Publications
Griffin TM, Friedman JE. How can parental obesity promote OA across generations? Nature Rev Rheumatology. 2020. Mar;16(3):129-130. PMID: 31949286
Batushansky A, Lopes EBP, Zhu S, Humphries KM, Griffin TM. GC-MS Method for Metabolic Profiling of Mouse Femoral Head Articular Cartilage Reveals Distinct Effects of Tissue Culture and Development. Osteoarthritis and Cartilage. 2019. 27(9);1361-1371. PMID: 31136803 PMCID: PMC6702098
Issa R, Boeving M, Kinter M, Griffin TM. Effect of biomechanical stress on endogenous antioxidant networks in bovine articular cartilage. J Orthop Res. 2018 Feb; 36(2):760–9. PMID: 28892196 PMCID: 5839935
Berenbaum F, Griffin TM, Liu-Bryan R. Review: Metabolic regulation of inflammation in osteoarthritis. Arthritis Rheumatol. 2017 Jan;69(1):9-21. PMID: 27564539 PMCID: PMC5341385
Barboza E, Hudson J, Chang WP, Kovats S, Towner RA, Silasi-Mansat R, Lupu F, Kent C, Griffin TM. Pro-fibrotic infrapatellar fat pad remodeling without M1-macrophage polarization precedes knee osteoarthritis in diet-induced obese mice. Arthritis Rheumatol. 2017. Jun;69(6):1221-1232. PMID: 28141918 PMCID: PMC5449220
Fu Y, Kinter M, Hudson J, Humphries KM, Lane RS, White JR, Hakim M, Pan Y, Verdin E, Griffin TM. Aging promotes SIRT3-dependent cartilage SOD2 acetylation and osteoarthritis. Arthritis Rheumatol. 2016 Aug;68(8):1887-98. PMID: 26866626 PMCID: PMC5331855
Contact
Aging & Metabolism Research Program, MS 21
Oklahoma Medical Research Foundation
825 N.E. 13th Street
Oklahoma City, OK 73104
Phone: (405) 271-7579
Fax: (405) 271-1437
E-mail: Tim-Griffin@omrf.org
Lab Staff
Padmaja Mehta D'souza, Ph.D.
Staff Scientist
Albert Batushansky, Ph.D.
Assistant Staff Scientist
Ravi Komaravolu, Ph.D.
Postdoctoral Fellow
Sanique South, Ph.D.
Postdoctoral Fellow
Jessica Lumry
Biomedical Engineer
Taylor Block
Senior Research Technician
Kamil Kobak
Research Trainee (Polish Student Exchange Program)
News from the Griffin lab
A new wave of researchers has joined the Oklahoma Medical Research Foundation’s scientific staff as part of the foundation’s expansion. OMRF has added seven new scientists to its staff. In addition, two research assistants have been promoted to faculty-level positions. The new researchers have come to OMRF from a variety of institutions across the U.S. […]