Abstract
Avascular necrosis (AVN) is a disorder leading to femoral head (FH) destruction, while BMPs are known for their osteogenic ability. In this study we analyzed BMP-2, BMP-4, BMP-6 and BMP-7 expression at the RNA and protein level in the normal and necrotic sites of the FHs.
Quantitative RT-PCR for BMP-2,-4,-6,-7 genes was performed in samples from the normal and necrotic sites of 52 FHs with AVN. Protein levels of BMP-2,-4,-6 were estimated by Western Blot analysis. Statistical analysis was performed using the t-test (p< 0.05).
BMP-2 and BMP-6 mRNA levels were higher in the normal than the necrotic site (BMP-2 and BMP-6, normal vs necrotic: 16.8 vs 7.5 and 2 vs 1.66, respectively). On the contrary, BMP-4 mRNA levels were higher in the necrotic (1.2) than the normal site (0.97), while BMP-7 mRNA levels were low in both sites. At the protein level, BMP-2 expressed higher in the normal (0.63) than the necrotic region (0.58), while BMP-4 and BMP-6 detected at higher levels in the necrotic site (BMP-4 and BMP-6, normal vs necrotic: 0.51 vs 0.61 and 0.52 vs 0.57, respectively).
Different mRNA levels between the normal and necrotic site, as well as discrepancies between the gene and protein BMPs expression levels suggest a different regulation mechanism between the two regions. Better understanding of the expression pattern of BMPs could lead to a more successful use of these molecules in the prevention and treatment of AVN
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
