Figure 7
Effect of diosgenin on DNA fragmentation after incubation with celecoxib (an inhibitor of cyclooxygenase-2 [COX-2]) (a) or exogenous prostaglandin E2 (PGE2) (b). (a) Human rheumatoid arthritis fibroblast-like synoviocytes (FLS) were preincubated with or without celecoxib (1 μM) for 4 hours and then 40 μM diosgenin was added for 24 or 48 hours. Measurements were made on FLS from four different patients. Data are expressed as mean ± SD of four experiments. *,#A P value of less than 0.05 (Fisher's protected-least-significant-difference test [PLSD]) was considered to indicate significance in comparison with diosgenin alone. (b) Cells were preincubated with or without celecoxib (1 μM) in the absence or presence of PGE2 (10 nM) for 4 hours, followed by incubation with 40 μM diosgenin for an additional 24 hours. Measurements were made on FLS from four different patients. Data are expressed as mean ± SD of four experiments. *A P-value of less than 0.05 (Fisher's PLSD test) was considered to indicate significance in comparison with diosgenin alone. OD, optical density.