ABSTRACT
Immortalized human precartilaginous stem cells (IPSCs) were established to provide stable cell resource for the study of the molecular mechanism of gene targeting on the differentiation of PSCs.Plasmid pCMVSV40T/PUR containing simian virus 40 large T antigen gene (SV40Tag) was transfected into human PSCs by using lipofectin transfection.Colonies were isolated by puromycin selection and expanded by multiple passages,lmmunohistochemistry,RT-PCR and Southern blotting were used to identify the transfected cells and to detect the expression and integration of SV40Tag in expanded cell lines.The positive colonies were isolated and subcultured,designated immortalized precartilaginous stem cells (IPSCs),which were confirmed as fibroblast growth factor receptor-3 (FGFR-3) positive cells by immunohistochemistry and RT-PCR.SV40Tag cDNA was found in cultured IPSCs of passage 8 by Southern blotting,and the expressions of SV40Tag mRNA and protein were confirmed by RT-PCR.These findings suggested that IPSCs strain with SV40Tag was constructed successfully.
ABSTRACT
To investigate the preventive effect of epimedium-defivod phytoestrogen (PE) on osteoporosis induced by ovariectomy (OVX) in rats, 11-month-old female Wistar rats were randomly di- vided into Sham, OVX and PE groups. One week after OVX, daily oral administration of PE (0.4 g·kg-1·day·-1) started in PE group, and rats in Sham and OVX groups were given vehicle accordingly. The administrations lasted for 12 weeks. The biological markers including serum osteocalcin (OC) and urinary deoxypyridinoline (DPD) for bone turnover were evaluated at the end of the 12th week. On the 13th week, all the rats were sacrificed. The right proximal tibiae were removed, subjected to micro CT for determination of trabeonlar bone structure and then bone histomorphometry was per- formed to assess bone remodeling. The OVX rats were in a high bone turnover status as evidenced by increased bone formation markers and bone resorption markers. Treatment with PE could suppress the high bone turnover rate in OVX rats. Micro CT data revealed that PE treatment could ameliorate the deterioration of the micro-architecture of proximal tibiae induced by OVX, as demonstrated by greater bone volume, increased trabecular thickness and less trahecular separation in PE group in comparison with OVX group. The static and dynamic parameters of bone histomorphometry indi- cated that there were significant increases in bone formation variables and significant decreases in bone resorption variables between PE and OVX groups. The findings suggest that PE has a beneficial effect on trabecular bone in OVX rat model and this effect is possibly associated with stimulation of bone formation as well as inhibition of bone resorption.