No abstract

SummaryThe effects of water-soluble and -insoluble indigestible saccharides (IDS) on immune responses of the intestinal tract were studied. Male 4-week-old Sprague Dawley rats were fed for three weeks on diets containing several kinds of IDS at 5%. The results revealed that the proportion of u-light chain and IgA-presenting lymphocytes in small intestinal and cecal mucosa differed in increased number depending on the type of IDS. The response of colonic mucosa was not pronounced.

Significant increases in the amounts of short-chain fatty acids and lactate, and in numbers of bifidobacteria were observed in the cecum of curdlan (CD) -fed rats as compared with those of cellulose-fed ones. The in vitro proliferation of 5 species of bifidobacteria was markedly increased in the cultures containing the supernatant obtained from the cecal contents of CD-fed rats. These findings suggest that bifidus factors have been produced in the cecum of CD-fed rats.

No abstract

The aim of this study was to estimate the contributions of dietary n–3 polyunsaturated fatty acid (PUFA), a representative dietary immunosuppressant, to the activity of both alveolar macrophages (AM) and natural killer (NK) cells, and compare them to those of n–6 PUFA. Twelve 5-week-old female Sprague-Dawley rats were divided into two dietary groups, one fed a 10% fat diet for 9 weeks enriched with n–3 PUFA (n–3 diet) and the other an n–6 PUFA (n–6 diet). AM reduced the release of nitric oxide, monocyte chemoattractant protein 1 and tumor necrosis factor α in the rats fed the n–3 diet, compared with rats fed the n–6 diet. NK cell activity was reduced by consumption of the n–3 diet. This study suggests that consumption of n–3 PUFA can ameliorate pulmonary inflammatory disorders which are affected by the reduction of not only proinflammatory cytokines but also chemokine released from AM.