Effects of Dexamethasone on Proliferation of Mesenchymal Stem Cells in Long Term Culture

Homeostasis of the body is maintained by balance of cell renewal, differentiation, and death. Dexamethasone has been used long time in field of MSCs research as differentiation inducer while, in contrast, there has been little work on the effect of dexamethasone on apoptosis and proliferation of MSCs. To determine the effect of dexamethasone on apoptosis and proliferation, MSCs were cultivated with (Dex) or without (Con) dexamethasone for 3 weeks. During this period weekly cell count, DNA assay, mitosis, apoptosis as well as alkaline phosphatase assay observation were recorded. DNA and cell number of Dex group was lower than Con group in early period but exceed at 3th week. There is no significant difference in mitosis between both groups whereas apoptosis frequency in Dex group was lower than that of in Con group. These results indicate that dexamethasone influences cell proliferation of MSCs in long term confluent culture by suppression of apoptosis.