Osteoblast recruitment from stem cells does not decrease by age at late adulthood

This study was aimed to characterize the ability of human bone marrow mesenchymal stem cells (MSC) to differentiate into osteoblasts in vitro. Twenty-three women and 20 men at late adulthood (52-92 years of age) were selected for the study. MSCs were isolated and cultured in vitro and alkaline phosphatase (ALP) activity, secretion of amino-terminal propeptide of type I procollagen (PINP), type III procollagen (PIIINP) and osteocalcin were analyzed. Matrix mineralization was analyzed by the von Kossa staining and by calcium quantification. We found that the ALP and PINP levels compared with control increased to 2.8- and 2.9-fold, respectively, when cells were cultured for three weeks. ALP activity, PINP and calcium deposition in response to dexamethasone treatment increased by age in women and was unchanged in men. Overall our data suggests that the osteogenic potential of MSCs does not decrease by age in either women or men at late adulthood. (C) 2003 Elsevier Inc. All rights reserved.