Figure 4

Morphologic changes of CIA. Representative hematoxylin/eosin-stained section of the joint was examined with light microscopy. The histologic evaluation of a joint from CIA-control mice (A, A1, and I) revealed inflammatory cell infiltration and bone erosion. The histologic alterations were significantly reduced in the tissues from CIA-PEA-LUT treated mice (B, B1, and I). Toluidine blue staining was also performed. A significant mast cell infiltration was observed in joint tissues of CIA-subjected mice (C, C1) compared with sham animals (data not shown). PEA-LUT enhanced the reduction of mast cell infiltration (D, D1). In addition, a significant increase in chymase and tryptase expression was found mainly in the joint tissues collected after CIA induction (E, E1, G, G1, and L). Chymase and tryptase expression was significantly attenuated in the joint from CIA-PEA-LUT-treated mice (F, F1, H, H1, and see L). Densitometry analysis of immunocytochemistry photographs (n = 5) for chymase and tryptase from paw sections was assessed (L). Data are expressed as percentage of total tissue area. *P < 0.01 versus Sham-control. °P < 0.01 versus CIA. ^# P < 0.01 versus CIA-PEA. ^§ P < 0.01 versus CIA-LUT.