Mineralized tissue cells are a principal source of FGF23.

While fibroblast growth factor (FGF) 23 is known as a phosphaturic factor in inherited and/or acquired hypophosphatemic disorders, it also serves an endocrine role in normal phosphate homeostasis. FGF23 acts negatively on the NaPi2a cotransporter and 25-hydroxy D(3)-1 alpha-hydroxylase with a resultant decrease in renal phosphate (Pi) reabsorption, while osteoblasts appear to be a primary source of FGF23 whose expression is counter-upregulated by 1 alpha,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)). Here we have shown the distribution of FGF23 in normal rat bone and tooth, and its expression profile in fetal rat calvaria (RC) cell cultures.

Expression and activity of hyaluronidase in human periodontal ligament fibroblasts.

Background: Hyaluronan is a major component of the extracellular matrix of periodontal ligament (PDL) contributing to the structural and functional integrity. Hyaluronans contribute to the buffering effect of the PDL during chewing, and they are also important in inflammation and wound healing. Hyaluronan is known to be synthesized and turned over by the resident PDL cells, although the mechanisms of hyaluronan metabolism still remain unclear.