FIGURE 2.

Celastrus/celastrol reduces bone resorption and osteoclast numbers in arthritic rats. A group each (n = 8 per group) of Mtb-immunized Lewis rats was fed either water (vehicle; A) or celastrus (3 g/kg; B) (left), whereas another group of each was injected intraperitoneally with either PBS (control; G) or celastrol (1 mg/kg; H) (right) as described in the legend to Fig. 1. Animals were euthanized on day 18, and their hind limbs were harvested, followed by embedding and processing for TRAP staining and bone histomorphometry. A, B, G, and H, representative micrographs of the stained histological sections showing TRAP-positive cells (20×); C and I, bone volume versus total tissue volume (BV/TV); D and J, the number of osteoclasts per tissue area (N.Oc/T Ar); E and K, active resorption per bone surface area (Oc.S/BS); F and L, the number of osteoclasts per bone perimeter (N.Oc/B.Pm). *, p < 0.05, comparing experimental and control groups. Error bars, S.E.