Muramyl Dipeptide Enhances Lipopolysaccharide-Induced Osteoclast Formation and Bone Resorption through Increased RANKL Expression in Stromal Cells

Figure 8

Enhancing lipopolysaccharide- (LPS-) induced Toll-like receptor (TLR4) expression using muramyl dipeptide (MDP) in vitro. Total RNA from bone marrow stromal cells was isolated after 4 days of incubation in culture medium supplemented with 1 ng/mL PTH, 10 ng/mL PTH, 1 ng/mL PTH and 10 μg/mL MDP, 10 μg/mL MDP, 100 ng/mL LPS, or 10 ng/mL LPS + 10 μg/mL MDP. mRNA levels for TLR4 were normalized to those of GAPDH. Results are expressed as the mean ± SD (; ). Differences were determined using Scheffe’s test.