Abstract:

BACKGROUND: Few studies addressing functional status of osteoblast integrin and regulation of integrin-signal transduction pathway. The effects of Jiangu granules on the expression of osteoblast integrin/focal adhesion kinase signal pathway remain poorly understood.

OBJECTIVE: To observe the effects of serum containing Jiangu granules on osteoblast adhesion, and to explore Jiangu granules on the expression of osteoblast integrin and regulation of signal transduction pathway. 
METHODS: Male healthy Sprague Dawley rats, aged 3-month, were prepared for serum containing Jiangu granules and intervented on the 3rd passages of rat osteoblasts. The expressions of fibronectin, type Ⅰ collagen and vitronectin were measured by ELISA. Phosphorylation of osteoblast focal adhesion kinase was detected by Western blot. And the mRNA expressions of fibronectin, type Ⅰ collagen, vitronectin and focal adhesion kinase were determined by real-time fluorescence quantitative PCR.
RESULTS AND CONCLUSION: The proliferation rate of osteoblasts was the fastest when the concentration of the serum containing Jiangu granules was 20%. The expressions of type Ⅰ collagen, fibronectin, vitronectin, focal adhesion kinase, as well as focal adhesion kinase phosphorylation were gradually increased with time prolonged (P < 0.05), which were obvious greater than those of the normal saline control group (P < 0.05 or P < 0.01). Jiangu granules-containing serum has direct or indirect role on osteoblast integrin signal transduction pathway relevant factors, promotes osteoblasts entering a virtuous circle of “secretion increasing→adhesion enhancing→activity enhancing, proliferation increased→secretion increasing”, and has a positive regulatory effect on the osteogenesis of osteoblasts.