INHIBITION OF OSTEOCLAST-LIKE CELL-FORMATION BY SODIUM-SALICYLATE ANDINDOMETHACIN IN MOUSE BONE-MARROW CULTURE

The present study examined the effect of sodium salicylate and indomet hacin on the recruitment of osteoclast-like cells in vitro. When mouse bone marrow cells were cultured for 8 days with 1 alpha,25-dihydroxyv itamin D-3 (1 alpha,25-(OH)(2)D-3, 10(-8) M), prostaglandin E(2) (PGE( 2), 10(-6) M) and recombinant human interleukin-1 alpha (rHIL-1 alpha, 2 ng/ml), numerous tartrate-resistant acid phosphatase (TRAP-positive ) multinucleated cells (MNCs) formed. Adding sodium salicylate or indo methacin inhibited the formation of TRAP-positive MNCs in a dose-depen dent manner. This inhibitory effect was more pronounced when the drugs were given at a later stage in the culture period. Indomethacin appea red to be more potent than sodium salicylate. PGE(2) production was in hibited by sodium salicylate or indomethacin. Exogenous PGE(2) failed to overcome the inhibitory effect of both drugs. These results suggest that sodium salicylate and indomethacin have inhibitory effects on th e recruitment of osteoclast-iike MNCs, preferentially on the later sta ge, and that PGE(2) is not the only compound targeted by these drugs i n reducing osteoclast-like cell formation in mouse bone marrow culture .