Mitochondria and mitochondrial variation have been recognized during the last years as important factors in the development of osteoarthritis (OA). Mitochondria are the energy powerhouse of the cell that also regulate different processes involved in the pathogenesis of OA. These include inflammation, apoptosis, calcium metabolism and the generation of reactive oxygen/nitrogen species (ROS/RNS).
Mitochondria contain their own genetic material, mitochondrial DNA (mtDNA), which evolved by the sequential accumulation of mtDNA variants permitting humans to adapt to different climates. ROS and reactive metabolic intermediates from mitochondrial metabolism are both regulated in part by mtDNA and are some of the signals transmitting information between mitochondria and the nucleus. These signals are able to alter nuclear gene expression and, when disrupted, affect a number of cellular processes and metabolic pathways leading to disease. In this session I will review the influence of mtDNA variation on OA-associated phenotypes, including those related to metabolism, inflammation and even aging, as well as nuclear epigenetic regulation,. This influence also enables the use of specific mtDNA haplogroups as complementary diagnostic and prognostic biomarkers of disease.