桑白皮提取物对破骨细胞 和成骨细胞活性的影响

目的:探究桑白皮提取物对破骨细胞和成骨细胞活性的影响。方法:通过回流提取和大孔树脂、聚酰胺柱层析制备桑白皮的四种提取物(水提物W、醇提物E、纯化提取物R和PA),采用可见分光光度法对不同提取物中的黄酮含量进行测定。采用1α,25-(OH)₂VitD₃诱导兔原代骨髓细胞以获得破骨细胞,诱导培养8 d后进行TRAP染色,通过TRAP+细胞计数考察桑白皮提取物对破骨细胞形成的影响。培养MC3T3-E1 Subclone 14细胞,采用MTT法考察桑白皮提取物对成骨细胞增殖的影响。结果:桑白皮四种提取物中黄酮的含量为:PA(37.23%) > R(26.80%) > E(21.83%) > W(15.38%)。提取物PA(10、20、50 mg/L)、R(20、50 mg/L)、E(10、20 mg/L)和W(20 mg/L)实验组与空白对照组相比,TRAP+细胞个数减少,且具有显著性差异(P<0.01或P<0.05)。MTT法增殖试验结果表明,四种提取物各剂量组均能促进MC3T3-E1 Subclone 14的增殖,与空白组相比具有极显著性差异(P<0.01),且促增殖作用随黄酮含量增加而增强。结论:桑白皮提取物能够抑制破骨细胞的形成,且对成骨细胞的增殖有促进作用,黄酮类化合物可能是桑白皮发挥活性作用的重要成分。

Effect of Cortex Mori Extract on the Activity of Osteoclasts and Osteoblasts

Objective:To evaluate the effect of Cortex Mori extract on the activity of osteoclasts and osteoblasts. Method:The water extract(W),ethanol extract(E),purified extract(R and PA) from Cortex Mori were prepared by reflux extraction,macroporous resin and polyamide column chromatography. The content of flavonoids in Cortex Mori extract was determined by visible spectrophotometry. Rabbit bone marrow cells were induced by 1α,25-(OH)₂VitD₃ to obtain the osteoclasts. After an 8-day osteoclastic induction,the cells were stained using the tartrate-resistant acid phosphatase(TRAP)kit. TRAP-positive cells were counted to evaluate the effect of Cortex Mori extract on osteoclast formation. MC3T3-E1 Subclone 14 cells were cultured and the effect of Cortex Mori extract on cell proliferation was determined by MTT assay. Result:The content of flavonoids in Cortex Mori extract was as follows:PA(37.23%)>R(26.80%)>E(21.83%)>W(15.38%). Extract PA(10,20,50 mg/L),R(20,50 mg/L),E(10,20 mg/L)and W(20 mg/L)were found to exhibit a lower number of TRAP-positive cells compared to the control group(P<0.01 or P<0.05). MTT assay indicated that all of the extracts could promote the proliferation of MC3T3-E1 Subclone 14 cell compared with the control group(P<0.01),and the proliferation effect was enhanced with the increase of flavonoid content. Conclusion:The study indicated that Cortex Mori extract could inhibit osteoclast formation and promote the proliferation of osteoblasts. Presumably,flavonoids might be the important bioactive component of Cortex Mori.