Effect of TNFα on osteoblastogenesis from mesenchymal stem cells

Background: Bone destruction and osteoporosis are accelerated in chronic inflammatory diseases, such as rheumatoid arthritis (RA) and periodontitis, in which many studies have shown the proinflammatory cytokines, especially TNF alpha, play an important role; TNF alpha causes osteoclast-induced bone destruction as well as the inhibition of osteoblastogenesis. Scope of review: Here we review our current understanding of the mechanism of the effect of TNF alpha on osteoblastogenesis from mesenchymal stem cells (MSCs). We also highlight the function of MSC in the pathogenesis of autoimmune diseases. Major conclusions: Many studies have revealed that TNF alpha inhibits osteoblastogenesis through several mechanisms. On the other hand, it has been also reported that TNF alpha promotes osteoblastogenesis. These discrepancies may depend on the cellular types, the model animals, and the timing and duration of TNF alpha administration. General significance: A full understanding of the role and function of TNF alpha on osteoblastogenesis from MSC may lead to targeted new therapies for chronic inflammation diseases, such as RA and periodontitis. (C) 2013 Elsevier B.V. All rights reserved.