Radiation therapy is an important treatment modality for abdominal or pelvic cancer, but there is a common and serious complication such as radiation-induced enteritis. Probiotics is reported to have positive effects against radiation-induced enteropathy. In this study, morphological changes of bowel mucosa were analyzed in rats to presume the effect of probiotics on radiation-induced enteritis and its correlation with radiation dose. A total of 48 adult male Sprague-Dawley rats were randomly assigned to two groups and received a solution containing 1.0x108 colony-forming units of Lactiobacillus acidophilus or water once daily for 10 days. Each of two groups was divided into three subgroups and abdomino-pelvic area of each subgroup was irradiated with 10, 15, and 20 Gy, respectively on the seventh day of feeding the solutions. All rats were sacrificed 3 days after irradiation and the mucosal thickness and villus height of jejunum, ileum and colon were measured. The morphological parameters of the small intestine represented significant differences between two solution groups irradiated 10 or 15 Gy, except for villus height of jejunum in 15 Gy-subgroup (P=0.065). There was no significant morphometric difference between two groups irradiated with 20 Gy of radiation. Probiotics appear to be effective for the morphological shortening of small intestinal mucosa damaged by radiation less than or equal to 15 Gy.
Animals ; Colon/pathology ; Disease Models, Animal ; Enteritis/pathology/prevention & control ; Ileum/pathology ; Intestinal Mucosa/microbiology/*radiation effects ; Intestine, Small ; Jejunum/pathology ; Lactobacillus acidophilus/*metabolism ; Male ; Probiotics/administration & dosage/*pharmacology ; Radiation Injuries, Experimental/*prevention & control/therapy ; Radiation Protection/*methods ; Random Allocation ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo observe the changes in intestinal mucosal permeability in rats with methotrexate (MTX)-induced small intestinal damage and investigate the protective effects of curcumin.

METHODSThe experiment was carried out using 4 groups of rats, namely the normal control group, enteritis model group, sulfasalazine (SASP) group and curcumin group. With the exception of the rats in the normal control group, all rats were subjected to intraperitoneal MTX injection to induce enteritis and received subsequent daily intragastric administration of SASP (100 mg/kg), curcumin (100 mg/kg), or normal saline for 5 days. The disease activity index (DAI), colonic mucosal damage index (CMDI) and histological score (HS) of the rats were evaluated. The levels of diamine oxidase (DAO) and D-lactate were assessed using spectrophotometric assay, and myeloperoxidase (MPO) activity and intracellular adhesion molecule-1 (ICAM-1) protein expression were measured by biochemical and immunohistochemical methods, respectively.

RESULTSCompared with the normal control group, the rats in the model group showed significantly increased DAI, CMDI and HS and levels of DAO, D-lactate, ICAM-1 and MPO. Curcumin treatment resulted in significantly decreased DAI, CMDI, HS and lowered activities of D-lactate, ICAM-1 and MPO in comparison with the model group (P<0.01).

CONCLUSIONMTX induces increased mucosal permeability of the small intestines in rats, and curcumin may offer protective effects against MTX-induced rat enteritis by lowering the intestinal mucosal permeability.

Amine Oxidase (Copper-Containing) ; metabolism ; Animals ; Anti-Inflammatory Agents, Non-Steroidal ; pharmacology ; Curcumin ; pharmacology ; Enteritis ; chemically induced ; pathology ; prevention & control ; Female ; Immunohistochemistry ; Intercellular Adhesion Molecule-1 ; metabolism ; Intestinal Mucosa ; drug effects ; metabolism ; pathology ; Intestine, Small ; drug effects ; metabolism ; pathology ; Methotrexate ; Peroxidase ; metabolism ; Rats ; Rats, Sprague-Dawley ; Spectrophotometry