Abstract
Periosteum is a specialized connective tissue that surrounds bone, containing progenitor cells that develop into osteoblasts. The osteo-progenitor cells along with growth factors, such as BMPs, play critical role in development, reconstruction and bone formation. Aim: to evaluate the expression of BMPs in human periosteum and in different subrgroups, including different donor sites, gender, and smoking habits.
Gene expression of BMPs 2,4,6,7 was performed in 60 periosteal samples using quantitative RT-PCR. Samples were obtained from 32 men/28 women, 22 smokers/38 non-smokers, 29 lower/31 upper extremities.
BMP2 gene expression was significantly higher (median: 12.02, p< 0.05) than the mRNA levels of BMPs 4,6,7 (median: 1.36, 2.55, 0.04) in all samples. BMP2 mRNA levels were higher in large compared to small bones (median: 13.4 vs 9.48), while BMPs 4,6,7 gene expression was similar (1.3 vs 1.4, 2.7 vs 2.1, 0.04 vs 0.03, respectively). In lower extremities, BMPs mRNA levels were higher than in the upper; the same was detected in non-smokers versus smokers group (BMPs2,4,6,7: 13.9 vs 1.5, 3.1 vs 0.048, 8.7 vs 1.06, 1.6 vs 0.026, respectively). mRNA transcripts of BMP2 were higher in men than women (median: 13.1 vs 10.8).
In our study, BMP2 expression is characteristically higher than that of BMP4, BMP6 and BMP7, highlighting the critical role that BMP2 plays in bone homeostasis. Furthermore, the elevated expression of BMP2 in men towards women, and of all BMPs of the lower extremity samples indicate the effect of hormones and mechanical factors in periosteal BMPs gene regulation; while the effect of smoking is reflected in the reduction of BMPs expression in smokers.
Correspondence should be addressed to Anastasia C. Tilentzoglou MD, General Secretary of the Board of Directors of HAOST, 20 A. Fleming Str. (N.Filothei), Gr. 15123 Maroussi, Athens Greece. E-mail: info@eexot.gr
