Microbiomics Researchers to Explain How Changes in Diet May Help Treat OA

The various disciplines that make up the field of omics play an increasing role in cutting-edge research across medicine, and rheumatology is no exception. Microbiomics will be the subject of the Sunday, Nov. 12, session State of the Art: Microbiome Niches in OA.

The session will begin at 9 a.m. PT in Exhibit Hall A-B of the San Diego Convention Center. It will be livestreamed for online viewing and available on demand within 24 hours of the session for registered ACR Convergence 2023 participants.

While researchers have previously focused on the role of the human gut microbiome in autoimmune disease, relatively little attention has been paid to the microbiome in osteoarthritis (OA).

“Unlike many other autoimmune rheumatologic conditions, we don’t have any disease-modifying drugs at all in osteoarthritis,” said Matlock Jeffries, MD, Associate Professor at the Oklahoma Medical Research Foundation. He will discuss the articular microbiome in OA, including its potential role in OA pathogenesis.  

“OA is at least an order of magnitude more common than many of our autoimmune rheumatic diseases, and yet we have a surprisingly poor understanding of OA pathogenesis,” Dr. Jeffries said. “There is a genetic component to OA, but genetic risk is not particularly strong, especially for knee OA. Therefore, many of us in the OA research field have begun focusing on non-genetic factors.”

Researchers are just beginning to piece together the roles of various environmental perturbations on OA.

“The microbiome is a really interesting integrator of environmental inputs, including diet, exercise, etc. If patients change their diet in certain ways, it certainly has an effect on the gut microbiome, and may also change microbial signatures in other locations like joints,” Dr. Jeffries explained. “Furthermore, we know from work in other chronic diseases that the microbiome drives chronic inflammation, and OA, as we understand it now, has a component of chronic, low-level inflammation.”

New data is emerging on the potential role of cartilage microbial signatures in obesity, aging, and other conditions associated with OA.

“Our initial work was in human subjects, but a lot of this more recent work will be in mouse models,” said Dr. Jeffries, who was senior author on “Identification of Cartilage Microbial DNA Signatures and Associations With Knee and Hip Osteoarthritis,” published in Arthritis & Rheumatology in 2020.

Dr. Jeffries also intends to review recent publications on the microbiome of the synovium (the lining of the joint) and the synovial fluid.

“What we and others have found is that a lot of risk factors like aging and obesity are independently inducing a number of microbiome changes that are strikingly similar to those associated with OA itself,” he explained.

Dr. Jeffries noted that the recent expansion of microbiome work is in no small part due to the ever-falling cost of sequencing.  

“Historically, it was prohibitively expensive to do the depth of sequencing necessary to get species-level data, but the cost has come down dramatically over the past few years,” he said.

Another speaker during the session, Liubov Arbeeva, MSc, a Biostatistician at the University of North Carolina in Chapel Hill, will discuss the dynamics of fecal and plasma microbiome composition, microbial metabolomics, and leaky gut in obesity-associated OA.