The role of STAT3 in osteoclast mediated bone resorption

Abstract

Signal Transducer and Activator of Transcription 3 (STAT3) is known to be related to bone metabolism. Mutation of STAT3 causes a rare disorder in which serum levels of IgE are elevated. This causes various skeletal problems similar to osteoporosis. To examine the effect of STAT3 in the osteoclast, we obtained two osteoclast specific STAT3 knockout mouse models: one using the CTSK promoter to drive Cre recombinase and another using a TRAP promoter. Examination of these mice at 8 weeks of age revealed a decreased trabecular bone volume in CTSK specific STAT3 knockout mice along with a slight decrease in osteoclast number in both CTSK and TRAP specific STAT3 knockout females. We also noticed changes in bone mineral density and bone mechanical strength in females. These data suggest that STAT3 plays a part in the function of the osteoclast.