Protection of apoptosis of osteoblast cultured in vitro by Morinda Root Polysaccharide / 中国骨伤

ABSTRACT

<p><b>OBJECTIVE</b>To explore the protection on apoptosis and the mechanism of promoting the cytoactive of osteoblast by Morinda Root Polysaccharide through the observations of the cultured osteoblast in vitro.</p><p><b>METHODS</b>Prepared blood serum with Morinda Root Polysaccharide and Morinda Root aqueous extract and cultured Osteoblast in vitro with it. The second generation osteoblasts in vitro were separated from the cranium of 24-hours newborn SD rat, which were divided into control group (adding only rat serum during cultivation), induction apoptosis group (adding trans-retinoic acid in control group), Morinda Root aqueous extract group (adding serum prepared by Morinda Root aqueous extract in induction apoptosis group) and Morinda Root Polysaccharide group (adding serum prepared by Morinda Root Polysaccharide in induction apoptosis group). Adopting fluorescence microscope, apoptosis detected by flow cytometry and gene expression of Bcl-2 and Bax detected by RT-PCR, to evaluate the effect of Morinda Root Polysaccharide on the course of osteoblast apoptosis.</p><p><b>RESULTS</b>The apoptotic rate of Morinda Root aqueous extract group and Morinda Root Polysaccharide group were significantly lower than that of induction apoptosis group (P < 0.01). The apoptosis ratio of Morinda Root Polysaccharide group was lower than that of Morinda Root aqueous extract group (P < 0.05). Expression level of Bcl-2 mRNA of apoptosis cell control group > Morinda Root Polysaccharide group > Morinda Root aqueous extract group > induction apoptosis group (P < 0.01). Expression level of Bax mRNA induction apoptosis group > Morinda Root aqueous extract group > control group > Morinda Root Polysaccharide group (P < 0.01). Bcl-2/Bax control group > Morinda Root Polysaccharide group > Morinda Root aqueous extract group > induction apoptosis group (P < 0.01).</p><p><b>CONCLUSION</b>Morinda Root can inhibit the apoptosis of osteoblast induced by trans-retinoic acid in some extent. The above role of Morinda Root Polysaccharide is significant better than that of Morinda Root aqueous extract. It is indicated that Morinda Root Polysaccharide is one of the essential component of inhibiting osteoblast apotosis.</p>