Award: Arthritis and Related Autoimmune Disease Research Grant
Biography: Dr. Naomi Dirckx, PhD, is an Assistant Professor in the Department of Orthopaedic Surgery at Washington University in St. Louis, where she leads an independent research program focused on the metabolic regulation of skeletal tissues. Her work centers on citrate biology and the plasma membrane citrate transporter SLC13A5 (NaCT), with the goal of uncovering metabolism-based mechanisms that control bone and cartilage integrity in health, aging, and disease.
Dr. Dirckx received her doctoral training at KU Leuven in Belgium and completed her postdoctoral studies at Johns Hopkins University. There, she identified a critical role for SLC13A5-dependent citrate metabolism in osteoblast function and bone mineralization, establishing citrate as a key regulator of skeletal material properties and linking cellular metabolism to bone quality.
Since launching her laboratory in 2024, Dr. Dirckx has expanded her research into articular cartilage and osteoarthritis, integrating multi-omics approaches (including metabolomics, spatial transcriptomics, and in vivo metabolic tracing) to define how citrate supports extracellular matrix assembly and tissue resilience.
As a bone biologist entering the osteoarthritis field, support from the ANRF is particularly meaningful. This award provides critical momentum to establish a new research direction focused on cartilage biology and post-traumatic osteoarthritis, and enables Dr. Dirckx to build a strong foundation for future translational and NIH-funded studies.
Dr. Dirckx is dedicated to mentoring trainees and fostering interdisciplinary collaboration. Her research aims to develop innovative, metabolism-based strategies to preserve skeletal health and prevent degenerative musculoskeletal diseases.
Research Summary: Articular cartilage is the smooth tissue that covers the ends of bones in joints and allows painless movement. Once damaged, cartilage has very little ability to heal on its own. Current treatments for cartilage injury and osteoarthritis mainly focus on reducing pain and inflammation, and ultimately, replacing the joint. There are no therapies that truly repair or rebuild damaged cartilage. One major reason is that we do not fully understand how cartilage cells make and maintain the strong matrix that gives cartilage its protective function. Cartilage cells, called chondrocytes, must continuously produce large amounts of matrix molecules to keep joints healthy. This process requires energy and specific building blocks, but the metabolic pathways that support cartilage matrix production are not well understood.
Citrate is a small molecule that plays an important role in cell metabolism, helping cells generate energy and produce materials needed for tissue growth. However, its role in cartilage has not been studied. Our early findings show that cartilage cells actively take up citrate using a transporter called SLC13A5. When this transporter is missing, cartilage cells cannot properly form their matrix. We also found that SLC13A5 levels are higher in damaged regions of human osteoarthritis cartilage, suggesting it may be part of the body’s attempt to repair injury. This project will study how citrate metabolism supports cartilage formation and repair after joint injury. Using advanced metabolic and imaging tools, we will determine how changes in citrate use affect cartilage health. This work aims to uncover new biological targets that could lead to therapies that help cartilage heal, rather than simply treating symptoms.
Links:
https://orthopaedicresearch.wustl.edu/labs/naomi-dirckx