Efffects of 17β-estradiol(17β-E2) on the cytoskeleton and bone resorption of cultured osteoclasts in vitro

Objective To study the effects of 17β-E 2 on the cytoskeleton of cultured osteoclasts and how it effects on bone resorption via osteoclasts in vitro.Methods 17β-E 2 with different concentration were added to osteoclasts culture medium and the cytoskeleton of osteoclasts were stained with F-actin specified immunofluorescence antibody. The changes of cytoskeleton were observed with laser scanning cinocal microscopy(LSCM) and the area and number of resorption pits were observed with scanning electric microscopy.Results With the concentration of 17β-E 2 increased relative fluorescence value of F-actin of osteoclasts decreased from (89.6±7.5)% to (34.7±5.4)% actin filaments in osteoclasts contracts shortens and were disarranged the spreading area of osteoclasts decreased from (1289±53)μm 2/nucleus to (406±42)μm 2 nucleus at the same time the area and number of the resorption pits reduced from (2157±51)μm 2 and (131.5±11.7)/slice to (965±75)μm 2 and (16.8±4.0)/slice respectively.Conclusion 17β-E 2 can not only regulate the expression of F-actin of osteoclasts, but also change the arrangement of cytoskeleton to inhibits the motility of osteoclasts. Therefore to inhibit the bone resorption by osteoclasts.