Influence of amrinone on intestinal villus blood flow during endotoxemia

Indomethacin-induced small intestinal injury is ameliorated by cilostazol, a specific PDE-3 inhibitor

BACKGROUND

Neutrophil migration, one of the major factors predisposing to nonsteroidal anti-inflammatory drugs (NSAIDs)-induced intestinal lesions, consists of several steps, including interaction with P-selectin from platelets. Cilostazol, a specific phosphodiesterase (PDE)-3 inhibitor, suppresses the expression of P-selectin from platelets and reduces interaction between platelets and leukocytes, leading to inflammatory amelioration in several disease models. We tried to clarify the therapeutic effectiveness of cilostazol for NSAID-induced small intestinal lesions.

SUBJECTS AND METHODS

1) Anti-PSGL-1 antibody (2 mg/kg) or cilostazol (100 mg/kg) was administered to mice one hour before Indomethacin (IND, 2.5 mg/kg) administration for 4 days to evaluate small intestinal lesions. 2) IND-induced migratory behaviors of neutrophils and platelets were evaluated in intestinal vessels by an intravital microscopy.

RESULTS

i) IND induced small intestinal lesions with an increase in MPO activity. Anti-PSGL-1 antibody and cilostazol ameliorated intestinal lesions along with suppression of MPO activity. ii) Intravital microscopy revealed that administration of IND increased migration of platelet-bearing neutrophils. Cilostazol treatment ameliorated neutrophil migration by blocking interaction between platelets and neutrophils.

CONCLUSION

Our results suggest that enhanced platelets-bearing neutrophil migration is critically involved in the pathogenesis of IND-induced small intestinal lesions and suggest a potential application of cilostazol for prevention of NSAID-induced small intestinal lesions.

Cilostazol, a specific PDE-3 inhibitor, ameliorates chronic ileitis via suppression of interaction of platelets with monocytes

Excessive migration of monocytes to a site of intestinal inflammation contributes to tissue damage in Crohn's disease. It is known that cilostazol, a specific phosphodiesterase-3 (PDE-3) inhibitor of platelets, decreases monocyte recruitment to intestinal mucosa through suppression of platelet-monocyte interactions. The objective of this study was to clarify whether cilostazol ameliorates murine ileitis by suppression of monocyte migration. Significant inflammation was induced in the ileum of SAMP1/Yit mice at 23 wk of age after piroxicam treatment for 3 wk. Weight of the terminal ileum of mice was significantly greater with inflammatory cell infiltration in SAMP1/Yit mice than in control mice (AKR-J). Treatment of SAMP1/Yit mice with cilostazol-containing food (200 ppm) for 3 wk significantly attenuated the increase in intestinal weight and the histological changes, including invasion of F4/80-positive macrophages. A significant increase in migration of monocytes and platelets to microvessels of the ileal mucosa was observed in SAMP/Yit mice in vivo by using an intravital fluorescence microscope. Pretreatment with cilostazol significantly attenuated the increased migration of monocytes, possibly through suppression of platelet-monocyte interactions. In conclusion, a PDE-3 inhibitor ameliorates murine ileitis through attenuating migration of monocytes to the intestinal mucosa, suggesting a potential usefulness of antiplatelet drugs for treatment of Crohn's disease.