Role of Extracellular Vesicle Cargo in Osteoclast Differentiation Traumatic Brain Injury Bone Loss Mouse Model

Abstract

MicroRNAs (miRNAs) have been known to play a key role in bone regulation. Some miRNAs have been observed to increase bone formation via osteoblast formation and others seem to be involved in bone resorption via osteoclast formation. In this study, we aim to observe which cargo in the bone marrow derived exosomes during a traumatic brain injury (TBI) are involved in bone resorption. Using mouse bone marrow monocytes (mBMCs), we have induced osteoclast formation by feeding media containing macrophage colony stimulating factor (MCSF) as well as receptor activator of nuclear factor kappa-B ligand (RANK-L). Along with osteoclastogenesis observed via tartrate resistant acid phosphatase (TRAP) staining, we report from mass spectrometry and quantitative reverse transcription real-time polymerase chain reaction (qRT-PCR) data that protein S100A9 and miR-199a, miR-151, miR-351, miR-92a, miR-92b, miR-1940 enhance osteoclast differentiation. Receptors for S100A9 as well as the inflammatory cytokine TNF-alpha are seen to be upregulated as a result of osteoclastogenesis. The observations from this study can contribute insight for creating possible therapeutic methods for osteoporosis related diseases.