ABSTRACT
Objective:To investigate the effects of different concentrations of Astragali Radix containing serum on the expression of 24-hydroxylase（CYP24A1），1α-OHase（CYP27B1） mRNA and protein in rat bone marrow mesenchymal stem cells （BMSCs）， and to explore the mechanism of primary osteoporosis （OP）. Method:The experiment was divided into 6 groups，like normal group， model group， low ，middle and high dose group of Astragali Radix containing serum（20%，40%，60%），Vitamin D group. Cell proliferation toxicity assay（CCK-8） was used to detect the effect of different concentrations of Astragali Radix containing serum on survival rate of aging BMSCs.Real-time quantitative PCR（Real-time PCR） and Western blot was used to detect the expression of CYP24A1 CYP27B1 mRNA and protein in senile BMSCs osteogenic differentiation cells by different concentrations of Astragali Radix containing serum. Result:Compared with normal group， the proliferation and survival rate of BMSCs osteoblasts induced by D-galactose in model group was significantly lower than that in normal group （P<0.01）. Compared with model group， medium and high dose groups and Vitamin D group could improve the proliferation and differentiation of aging BMSCs into osteoblasts in different degrees（P<0.01）. The relative expression of CYP27B1 mRNA and protein in model group was significantly lower than that in normal group， while the relative expression of CYP24A1 mRNA and protein in model group was significantly higher than that in normal group. Compared with model group， high dose Astragali Radix containing serum group could increase the relative expression of CYP27B1 mRNA and protein， and decrease the relative expression of CYP24A1 mRNA and protein in a dose-dependent manner（P<0.01）. Conclusion:The mechanism of different concentrations of Astragali Radix containing serum in the treatment of osteoporosis may be related to the regulation of CYP24A1， CYP27B1 mRNA and protein in the osteogenic differentiation of aging BMSCs.
ABSTRACT
Objective To study the expressions of 1,25 (OH) 2 D3,vitamin D receptor (VDR) and 24-hydroxylase (CYP24A1) and investigate the effects of 1,25 (OH)2D3 and its related molecules in the pathogenesis of Henoch-Sch(o)nlein purpura (HSP).Methods 1.The levels in the plasma 1,25 (OH) 2 D3 of 35 HSP patients and 14 healthy children were detected by enzyme-linked immunosorbent assay (ELISA).2.Total RNA of peripheral blood were extracted and transcribed into cDNA.Sybr green dye based real-time quantitative PCR method was used to compare the expression levels (indicated as 2-△ct value) of VDR and CYP24A1 in patients with HSP and those in the controls.Results The level of 1,25 (OH)2D3 was (13.29 ± 10.12) μg/L in plasma of HSP patients,lower than that of the healthy control group[(29.51-± 23.06) μg/L] (P ＜ 0.01).Compared with healthy control group,the level of VDR mRNA was higher but CYP24A1 mRNA was lower in HSP patients (P ＜ 0.05).Conclusion The patients with HSP have lower ability to synthesize active form of vitamin D and respond to VDR-mediated vitamin D effects,enhancing the ability to degrade this hormone.