Death Receptor 3 (TNFRSF25) Increases Mineral Apposition by Osteoblasts and Region Specific New Bone Formation in the Axial Skeleton of Male DBA/1 Mice

Figure 2

Expression of ALP, OPN, pro MMP-9, and mineral apposition in DR and DR osteoblast cultures. (a) DR () and DR () derived OB were cultured and the percentage of well area covered by ALP⁺ cells was calculated. ALP staining was significantly higher in the DR compared to the DR cultures across the 26-day time course (). Supernatants from OB cultures were tested for soluble levels of (b) OPN and (c) pro MMP-9. Across the time course significantly increased levels of OPN were detected in DR versus DR cultures (). (d) Levels of mineral apposition in the cultures were tested by alizarin-red staining. Significantly increased levels of mineralization were observed in the DR cultures at days 23 and 26 () compared to the DR. This translated into a significant increase in the level of mineral apposition across the 26-day time course ().

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