This protocol collectively addresses the following goals: 1) What are the changes in gene expression in osteoblasts and osteocytes that lead to impaired bone formation with aging; 2) Since recent work from the investigators' group has demonstrated that osteoclasts produce a number of growth factors and cytokines (coupling factors) that enhance osteoblast proliferation and/or differentiation, is aging associated with reduced osteoclast coupling factor production; and 3) If osteoclasts are markedly reduced using the FDA-approved medication for osteoporosis, denosumab, how does that effect the quantity of coupling factors in the bone microenvironment and the target genes of these coupling factors in osteoblasts?
This protocol addresses: 1) How gene expression changes in bone cells are affected by aging? 2) Is aging associated with decreased signaling between bone cells? 3) How does treatment with the osteoporosis medication denosumab affect bone cell signaling?