Beneficial Effects of Batimastat (BB-94), a Matrix Metalloproteinase Inhibitor, in Rat Experimental Colitis

Abstract

Background and Aims: Matrix metalloproteinases (MMPs) represent a group of enzymes that regulate cell-matrix composition playing a major role in the inflammatory response. In the present study we evaluated the ability of the MMP inhibitor Batimastat (BB-94) to modify the course of experimental colitis induced in the rat by trinitrobenzensulfonic acid (TNB). Methods: Colitis was induced in 40 rats by intracolonic administration of TNB. Animals were divided into four groups of ten rats each: group 1 received only intracolonic TNB, group 2 received TNB+5 mg/kg intraperitoneal BB-94, group 3 TNB+10 mg/kg BB-94 and group 4 TNB+20 mg/kg BB-94. The MMP inhibitor was administered 30 min before induction of colitis and twice daily until death. Ten rats receiving only intracolonic 0.9% saline served as controls. Animals were killed after seven days; segments of colon were removed and used for histological score of inflammation and myeloperoxidase (MPO) activity. Results: Rats receiving only intracolonic 0.9% saline showed no evidence of colitis. The inflammation score was 0.9, MPO activity 0.235 U/mg. Group 1 (TNB-treated rats) exhibited a high inflammation score (12.4) and MPO activity (0.715 U/mg). Conversely, BB-94-treated rats showed, compared to the TNB group, a significantly lower inflammation score and MPO activity in a dose-dependent fashion. Group 2: inflammatory score 10.1, MPO activity 0.474 (p < 0.05 vs. TNB); group 3: inflammatory score 8.3, MPO activity 0.287 (p < 0.01 vs. TNB); group 4: inflammatory score 5.0, MPO activity 0.256 (p < 0.01 vs. TNB). Conclusions: Treatment with BB-94 has dose-dependent beneficial effects on the inflammatory alterations in rat experimental colitis. Thus, the inhibition of MMPs may represent a novel therapeutic approach for treatment of intestinal inflammation.