The Study Of The Effect Of Ginkgo Biloba Extract On Osteoclast And The Related Mechanism

Objective:To study the effect of Ginkgo biloba extract(GBE)on the osteoclast and explore the related-mechanisms.Methods:The RAW264.7 cells were induced by RANKL and disturbed by GBE.This study were designed through RAW264.7 group,RAW264.7+RANKL group,RAW264.7+RANKL+0.075g·L-1GBE group and RAW264.7+RANKL +0.15g·L-1GBE group.TRAP staining method was used to test the size and number of osteoclast,the activity of osteoclast was assessed by the area of corresponding bone resorption pit.The apoptosis and cell cycle of RAW264.7 cell were tested by Flow cytometer.RT-PCR was used to evaluate the relative expression level of MMP 9,Casthepin K,DC-STAMP,NFATc1,Bcl-2,Bax,P27 and Cyclin-D1 in RAW264.7 cells.Results:The size and number of osteoclast in RAW264.7+RANKL+0.075g·L-1GBE group and RAW264.7+RANKL+0.15g·L-1GBE group,compared with RAW264.7+RANKL group,were significantly decreased(P<0.05).The area of bone resorption pit in RAW264.7+RANKL+0.075g· L-1GBE group and RAW264.7+RANKL+ 0.15g· L-1GBE group,compared with RAW264.7+RANKL group,were correspondly decreased(P<0.05).GBE increased the apoptosis of RAW264.7(P<0.05),the relative expression level of Bcl-2 and Bax changed correspondly(P<0.05).Compared with RAW264.7+RANKL group,the cell intercellular G0-G1 phase of RAW264.7+RANKL+0.075g·L-1GBE and 0.15g·L-1GBE groups was significantly shortened,corresponding to changes in the relative expression level of P27 and Cyclin-D1 in G0-G1 phase(P < 0.05).GBE inhibited the relative expression level of MMP9,Casthepin K,DC-STAMP and NFATc1 of RAW264.7 cell(P<0.05).Conclusion:GBE could inhibit the differentiation of osteoclast in RAW264.7 and bone resorption activity of osteoclast,and its related mechanisms may be related to promoting the apoptosis of RAW264.7 cells and shortening G0-G1 phase.