The protective effects of Ginkgo biloba extract (EGb 761) against free radical damage to osteoblast-like bone cells (MC3T3-E1) and the proliferative effects of EGb 761 on these cells
Jr. Brayboy et al., The protective effects of Ginkgo biloba extract (EGb 761) against free radical damage to osteoblast-like bone cells (MC3T3-E1) and the proliferative effects of EGb 761 on these cells, NUTR RES, 21(9), 2001, pp. 1275-1285
An extract of Ginkgo biloba which contains several antioxidative polyphenol
ics may prevent bone loss and osteoporosis-related bone fractures. The effe
cts of this Ginkgo biloba extract (EGb 761) on the proliferation of the MC3
T3-E1 cells, an osteoblast-like cell line, have been examined. Cells were c
ultured for 24 hr and then incubated with 1000 mug/mL or 2000 mug/mL of EGb
761 extract for another 6 hr. To test the antioxidative effects of EGb 761
, cells were exposed to the free radicals H2O2 and FeSO4. The MC3T3-E1 cell
proliferation was measured with the 3-(4,5-dimethylthiazolyl-2)-2,5-diphen
yltetrazolium bromide (MTT) cell proliferation assay, in which metabolicall
y active cells reduce tetrazolium MTT. Cell morphology was visualized using
BrdU (bromodeoxyuridine) labeling in order to establish necrosis as the me
chanism of cell death. A significant increase by 3.72-fold in MC3T3-E1 cell
proliferation was found with treatment of EGb 761 at 1000 mug/mL as compar
ed to the control (vehicle) group and 3.86-fold with treatment of EGb 761 a
t 2000 mug/mL as compared to the control group. EGb 761 may act by facilita
ting glucose uptake and pyruvate concentrations by these bone cells which l
eads to increased cellular energy and, hence, proliferation. In summary, a
dose-response of MC3T3-E1 cell proliferation was very positive for EGb 761.
However, the antioxidative effects of EGb 761 against free radical damage
showed a small but inconsistent protective effect. This study is the first
to examine the antioxidative effects of Ginkgo biloba extract on osteoblast
-like cells. These findings in cells in vitro may prove relevant to protect
ing against the loss of bone mass and the development of osteoporosis. in h
uman subjects. (C) 2001 Elsevier Science Inc. All rights reserved.