Original Article

Cancer Chemotherapy and Pharmacology

, Volume 65, Issue 6, pp 1117-1123

First online:

Oxidative stress and enhanced paracellular permeability in the small intestine of methotrexate-treated rats

  • Tomoko MaedaAffiliated withDepartment of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
  • , Yuko MiyazonoAffiliated withDepartment of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
  • , Kousei ItoAffiliated withDepartment of Pharmacy, Faculty of Medicine, The University of Tokyo Hospital, The University of Tokyo
  • , Kazuma HamadaAffiliated withDepartment of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
  • , Shuichi SekineAffiliated withDepartment of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University
  • , Toshiharu HorieAffiliated withDepartment of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Chiba University Email author 

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

Purpose

We previously demonstrated the increase of reactive oxygen species (ROS) production and myeloperoxidase (MPO) activity in the small intestine of methotrexate (MTX)-treated rats. In the present study, we investigated the role of ROS modulating intestinal mucosal permeability in this damage.

Method

MTX (20 mg/kg body weight) was administered to rats intravenously. N-Acetylcysteine (NAC; 80 mg/kg body wt), an antioxidant and a precursor of glutathione (GSH) was administered to rats intraperitoneally to investigate the contribution of ROS to the intestinal permeability enhancement. Intestinal permeability was evaluated by determining that of a poorly absorbable marker, fluorescein isothiocyanate-labeled dextran (FD-4; average molecular mass, 4.4 kDa) using the in vitro everted intestine technique. The occurrence of oxidative stress in the small intestine was assayed by measuring chemiluminescence and thiobarbituric acid reactive substances (TBARS) productions in mucosal homogenates of the small intestine.

Results

The mucosal permeability of FD-4 significantly (p < 0.01) increased in MTX-treated rats compared with control rats, as demonstrated by a twofold increase of FD-4 permeation clearance. This suggests an increase in paracellular permeability. Interestingly, the ROS production was observed preceding the increase of paracellular permeability. Treatment with NAC prevented the MTX-induced ROS production and the increase of paracellular permeability.

Conclusions

NAC protected the small intestine of rats from MTX-induced change in paracellular permeability, suggesting that ROS played an important role in the enhanced paracellular permeability.

Keywords

Methotrexate Reactive oxygen species Intestinal permeability Chemiluminescence N-Acetylcysteine Glutathione