(P20-030-23) Associations of Bacterially Derived Vitamin K Forms With the Intestinal Microbiome and Obesity-Related Osteoarthritis

Objectives: The overall goal of this study was to evaluate the association of intestinally-derived menaquinones with obesity-related osteoarthritis.

Methods: Fecal menaquinone concentrations and microbial composition were determined in 52 obese adults with hand and knee osteoarthritis and 42 age- and sex-matched obese controls without osteoarthritis. Principal component analysis was used to examine the inter-relationships between the fecal menaquinones. Differences in alpha and beta diversity and microbial composition across menaquinone clusters were evaluated using analysis of variance.

Results: Samples clustered into three groups: cluster 1 characterized by higher fecal menaquinone -8, -9, and -10 concentrations, cluster 2 characterized by lower overall menaquinone concentrations, and cluster 3 characterized by higher menaquinone-12 and -13. Overall, fecal menaquinone profiles did not differ between participants with or without osteoarthritis (p=0.707). Microbial diversity did not differ across the fecal menaquinone clusters (all F-test p >0.12). However, the relative abundance of bacterial taxa differed among clusters, with a higher abundance of Coprococcus, Prevotella, and Eggerthella in cluster 2 compared to cluster 1, a higher abundance of Oscilospira, Dorea and Eubacterium, and Bacteroides in cluster 3 compared to cluster 1, and a higher abundance of Prevotella, Sutterella and Dorea in cluster 3 compared to cluster 2 (all p< 0.001).

Conclusions: Menaquinones were variable and abundant in the human gut, but the fecal menaquinone profiles did not differ with osteoarthritis status. While the relative abundance of specific bacterial taxa differed among fecal menaquinone clusters, the relevance of these differences with respect to vitamin K status and human health is uncertain.

Funding Sources: Supported by the Tufts University CTSI NIH Clinical and Translational Science Award, the US Department of Agriculture, the Arthritis Foundation, the National Center for Advancing Translational Sciences (NCATS), and the National Institute of Arthritis and Musculoskeletal and Skin Diseases. The Johnston County Osteoarthritis Project is funded in part by the Centers for Disease Control and Prevention. The UNC Microbiome Core is supported in part by the National Institute of Diabetes and Digestive and Kidney Diseases.