| Osteoblasts are important cells in bone formation and, therefore, agents stimulating osteoblastic bone formation would have potential activity of anti-osteoporosis. In order to exploit novel and effective medicines preventing and treating osteoporosis and to promote the modernization of anti-osteoporostic Chinese Traditional Compound Medicines (CTCM), osteoblast-like UMR106 cells were employed as an in vitro model for investigating anti-osteoporostic medicines. The cell proliferation and differentiation were measured as active indices of stimulating osteoblastic bone formation. Qing'e prescription, which was one of "kidney-tonifying" CTCM on the basis of the theory of traditional Chinese medicines recorded in < TAIPING HUIMIN HEJI JUFANG>, was selected and examined extensively for the activity of stimulating osteoblastic bone formation in vitro in this study. The ethanol (75%) extract of Qing 'e prescription exhibited the maximal activity promoting osteoblastic proliferation and differentiation. The fractions of various polarity fractionated from the ethanol extract were further examined. The ethyl acetate fraction and aqueous fraction were found to be primarily active.The subtractive drug analysis method was used in the study of the disassemble formulae of Qing'e prescription. The effects of 11 subsidiary formulae from Qing'e prescription on osteoblastic proliferation and differentiation were examined. The results testified the compatibility of the four botanical drugs in Qing 'e prescription in cellular level for the first time and proved the rationality of prescription in a modernscientific way.In order to isolate the active constituents in ethyl acetate fraction of Qing'e prescription, ethyl acetate fraction and aqueous fractions of Eucommia ulmoides Oliv., activity-guided isolation was performed along with chromatographic techniques. Seven compounds were isolated and six compounds were identified with IR, NMR and MS data and physical-chemical properties. They were pinoresinol diglucopyranoside, psoralen and isopsoralen, which showed stimulating effects on osteoblastic proliferation and diffentiation, betulic acid and daucosterol exhibited activity of promoting cell proliferation significantly, and p-sitosterol. These results showed that pinoresinol diglucopyranoside, psoralen and isopsoralen were the mainly active constituents promoting osteoblastic proliferation and differentiation in Qing 'e prescription.The optimal extraction process of Qing'e prescription was studied by orthogonal design with extractive yield and the content of pinoresinol diglucopyranoside, psoralen and isopsoralen as the indices. Factors including the solvent ammount, concentration of ethanol and time of extraction were investigated in this experiment. The optimal condition was 75% ethanol, ten times of the amount of raw material, and three times for 2 hours each time.Eucommia ulmoides Oliv. and Psoralea corylifolia L. in Qing'e prescription were identified by TLC. Pinoresinol diglucopyranoside, psoralen and isopsoralen in Qing'e prescription were determined by RP-HPLC. The average content of pinoresinol diglucopyranoside, psoralen and isopsoralen in Qing'e prescription of 10 batches was 0.520 mgg-1'(RSD=3.2 %), 1.143 mgg-1(RSD=2.2 %) and 1.007 mgg-1(RSD=2.3%) respectively. The above methods were simple, rapid and accurate, and provided a qualitative and quantitative basis for the quality assessment of Qing 'e prescription.The ethanol extract of Qing'e prescription on ovariectimized rats, as a pharmacological model of osteoporosis, was studied and Gushukang granule served as a positive control. Compared with the OVX group, high dosage group (OVX+QEHgroup) increased bone mineral density and bone strength of rats, decreased alkaline phosphatase (ALP) activity and improved serum osteocalcin (BGP) and estradiol (E2) level markedly (P<0.05). These results indicated that Qing'e prescription might have some estrogen-like activity, inhibiting high bone turn-over effectively and have potential activity of anti-osteop...
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