Inflammation and Regeneration Vol. 26, No. 1, pp.49-53, 2006

Original Article

Evaluation of the combined effect of Mesalazine (Pentasa) and sodium ferrous citrate (SFC) on neutrophil functions

Daisuke KITAMURA1, Jian HUA2, Masaki HATA1, Tsutomu MAEDA1, Naohito TAKITA1, Masayuki KITAJIMA1, Takumi OCHIAI3, Isao NAGAOKA2, Toshiki KAMANO1

1Department of Coloproctological Surgery, 2Department of Host Defense and Biochemical Research, Juntendo University, School of Medicine, 3Department of Surgery, Tobu Chiiki Hospital, Tokyo Metropolitan Health and Medical Treatment Corporation

Abstract : INTRODUCTION: Mesalazine (Pentasa) is widely used for ulcerative colitis (UC). However, the anti-inflammatory actions of Mesalazine are not fully understood. In this study, we evaluated the actions of Mesalazine in vitro on the functions of neutrophil, a major inflammatory cell. Furthermore, we evaluated the combined effects of Mesalazine and sodium ferrous citrate (SFC) on neutrophil functions, since SFC is clinically administered to UC patients together with Mesalazine for treatment of chronic anemia associated with UC.
METHODS: Superoxide production by neutrophils was measured on the basis of superoxide dismutase-inhibitable cytochrome c reduction. Preincubated neutrophils were stimulated with fMLP, PMA or complement-opsonized zymosan particles. Cytochrome c reduction was calculated by the absorbance difference at 550 nm. Neutrophil migration was measured by a Boyden chamber assay with using zymosan-activated serum (C5a) as a chemotactic factor. Neutrophils were preincubated in the presence of 0.01-0.5 mM Mesalazine and then incubated with fMLP. The cells were further incubated with phycoerythrin (PE)-labeled anti-CD11b monoclonal antibody, and the expression of CD11b was analyzed by flow cytometry. Neutrophils were preincubated with 5 μg/ml SFC and 0.01-0.1 mM Mesalazine, and superoxide generation and migration were measured.
RESULTS: Mesalazine dose-dependently inhibited the superoxide production induced by PMA and fMLP at >0.05 mM. Furthermore, Mesalazine inhibited chemotaxis toward zymosan-activated serum in a dose-dependent fashion. Moreover, 0.5mM Mesalazine inhibited the fMLP-induced upregulation of CD11b expression. Interestingly, Mesalazine combined with SFC inhibited the superoxide generation and migration by neutrophils, compared with Mesalazine alone. Thus, the present observations suggest that a combined administration of Mesalazine and SFC may have a potential to reduce mucosal injury by suppressing neutrophil functions (migration, ROS generation and expression of adhesion molecule) in UC.