Effect Of Fluoxetine On Differentiation Of Mouse Osteoclast In Vitro

Background and ObjectiveWith the development of society,people’s consciousness of oral health is increasing day by day,and the number of the orthodontic patients has increased dramatically.It is found one interseting clinical event that the speed of teeth movement of one orthodontic patient who are taking antidepressants slowed down obviously,and gradually returned to normal level after medicine dose reduction.Fluoxetine is a new type of antidepressant,which is widely used in the treatment of depression because of its few adverse effects.In recent years,studies have found that fluoxetine has an affect on bone metabolism,leading to bone degenerative changes such as the decrease of bone mineral density and bone mass,the increase of bone fracture rate,and even short-term use will have a long-term effect on bone tissue,which is contradictory to the clinical phenomenon.It is speculated that different fluoxetine may have different effects on bone resorption function and break the balance of bone metabolism.Therefore,the purpose of this experiment is to verify the effect of fluoxetine on the proliferation,formation and differentiation of osteoclasts,and to provide a theoretical basis for clinical diagnosis and treatment.Methods1.The mouse osteoclast cultured in vitro and the study divided into 5 groups according to the final concentrations of fluoxetine,including the control group and the experimental group(0.01 μM,0.1 μM,1 μM,10 μM).The survival rate,cytotoxicity and lipid oxidation of cell membranes in each group were measured after 2 days,and the number of cell clones in each group was observed after 10 days.2.After osteoclastic induction,observing osteoclast by tartrate-resistant acid phosphatase staining after 5 days.After 5 and 10 days,the expression levels of matrix metallo proteinase 9,cathepsin K and Integrin β3 genes and proteins related to osteoclast differentiation were detected by RT-qPCR and Western blot,and the data were statistically analyzed by single factor analysis of variance(ANOVA).Result1.After 2 days,the cell survival rate of 10 μM was decreased significantly(P<0.001),the cytotoxicity and the degree of cell lipid oxidation were increased significantly(P<0.001).After 10 days,the number of cell clones of 10 μM was significantly lower than those in other groups(P<0.001).2.After 5 days of osteoclast induction,tartrate-resistant acid phosphatase positive cells appeared in all groups except for the uninduced group.And the number of positive cells was significantly increased in the 0.01 μM group and significantly decreased in the 10 μM group.After 5 days of osteoclast induction,the expression levels of osteoclast phenotypic genes and proteins up-regulated significantly in 0.01μM,down-regulated significantly in 10 μM.And after 10 days,the expression in 0.01μM group was still significantly up-regulated,and the expression in 0.1 μM group was down-regulated..ConclusionThe antidepressant fluoxetine have an effect on the proliferation and differentiation of osteoclasts.The proliferation of osteoclasts in the high-concentration fluoxetine group(10 μM)is inhibited.And the effect of fluoxetine on osteoclast differentiation are bidirectional.Fluoxetine of low concentration promotes osteoclast differentiation and high concentration inhibits it.With the extension of time,osteoclast differentiation in the low-concentration group of 0.1 μM to 10μM are also inhibited.