UNASSIGNED: Several inflammatory processes underlie excessive bone formation, including chronic inflammation of the spine, acute infections, or periarticular ossifications after trauma. This suggests that local factors in these conditions have osteogenic properties. Mesenchymal stem cells (MSCs) and their differentiated progeny contribute to bone healing by synthesizing extracellular matrix and inducing mineralization. Due to the variation in experimental designs used in vitro, there is controversy about the osteogenic potential of proinflammatory factors on MSCs. Our goal was to determine the specific conditions allowing the pro-osteogenic effects of distinct inflammatory stimuli. @entity1 bone marrow MSCs were exposed to @entity310 ( @entity310 ) and lipopolysaccharide (LPS). Cells were cultured in growth medium or osteogenic differentiation medium. Alternatively, @entity1841 ( @entity1841 ) was used as osteogenic supplement to simulate the conditions in vivo. Alkaline phosphatase activity and @entity460 deposition were indicators of osteogenicity. To elucidate lineage commitment-dependent effects, MSCs were pre-differentiated prior treatment. Our results show that @entity310 and LPS do not affect the expression of osteogenic markers by MSCs in the absence of an osteogenic supplement. In osteogenic differentiation medium or together with @entity1841 however, these mediators highly stimulated their alkaline phosphatase activity and subsequent matrix mineralization. In pre-osteoblasts, matrix mineralization was significantly increased by these mediators, but irrespective of the culture conditions. Our study shows that inflammatory factors potently enhance the osteogenic capacity of MSCs. These properties may be harnessed in bone regenerative strategies. Importantly, the commitment of MSCs to the osteogenic lineage greatly enhances their responsiveness to inflammatory signals.

Proinflammatory Mediators Enhance the Osteogenesis of XXXX Mesenchymal Stem Cells after Lineage Commitment.

@entity1 :: ('9606', 'Species') :: ['Human'] @entity310 :: ('7124', 'Gene') :: ['tumor necrosis factor alpha', 'TNF-a'] @entity1841 :: ('650', 'Gene') :: ['BMP-2', 'bone morphogenetic protein 2'] @entity460 :: ('MESH:D002118', 'Chemical') :: ['calcium']
@entity1 :: (9606,Species) :: ['Human']
