Figure 6.

DHA does not suppress LPS-induced osteoclast formation, bone resorption and production of osteoclast-related cytokines (TNF-α and RANKL) in Ffar4^(dE1/dE1) mice. (A) Microscopic images and numbers of TRAP-positive cells. Osteoclast precursor cells from Ffar4^(dE1/dE1) mice were treated with M-CSF, M-CSF+RANKL with or without DHA or DHA alone. TRAP staining was performed and TRAP-positive cells were counted. (B) Microscopic images and numbers of TRAP-positive cells. Osteoclast precursor cells from Ffar4^(dE1/dE1) mice were treated with M-CSF, M-CSF+TNF-α with or without DHA or DHA alone, and then TRAP staining was performed. TRAP-positive cells were counted. Scale bars = 100 μm. (C) Histological sections of calvariae were prepared from Ffar4^(dE1/dE1) mice after 5 days of daily supracalvarial administration of LPS (100 μg/day) with or without DHA (100 μg/day). Sections were stained with TRAP solution and hematoxylin counterstaining was performed. TRAP-positive cells were counted. Scale bars = 100 μm. (D) Histological sections of calvariae were prepared from Ffar4^dE1/dE1 mice after 5 days of daily supracalvarial administration of LPS (100 μg/day) with or without DHA (100 μg/day). The percentage of interface of bone marrow space covered by osteoclast and the number of TRAP-positive cell per millimeter of interface of bone marrow space were evaluated. (E) Micro-CT reconstruction images of calvariae. Images of calvariae excised from Ffar4^(dE1/dE1) mice after 5 days of daily supracalvarial administration of LPS (100 μg/day) with or without DHA (100 μg/day). Arrows indicate bone resorption areas and red areas indicate extensive bone resorption. Data are shown as means ± SD (n = 4; ^**p < 0.01, ^*p < 0.05). Differences were determined by Scheffe's test.