Diets containing different fermentable substrates can affect mucosal and systemic immune parameters in rats under homeostatic conditions

• Published in: Journal of functional foods Vol. 20; pp. 422 - 432
• Main Authors: Shastri, Padmaja, McCarville, Justin L., Brooks, Stephen P.J., Kalmokoff, Martin, Green-Johnson, Julia M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-01-2016; Elsevier
• Subjects: Cytokines; Dietary fibre; Liver; Resistant starch; SCFA; Sex; RS; IgA; IL; BCFA; CINC; Cytokines; IEC; Liver; Sex; Resistant starch; WB; SCFA; MLN; PRR; OB; TGF-β; Dietary fibre; TLR
• ISSN: 1756-4646; 2214-9414
• DOI: 10.1016/j.jff.2015.11.021

•Immune effects varied with diet and tissue examined.•A wheat bran-containing diet increased levels of IL-10 in the ileum of male rats and spleen of female rats.•Diets containing oat bran or resistant starch induced pro-inflammatory cytokine profiles in the colon and MLN, respectively.•Oat bran and resistant starch heightened levels of the regulatory cytokine TGF-β1 in the liver under resting conditions.
The effect of diets containing different fermentable substrates (resistant starch (RS), oat bran (OB) or wheat bran (WB)) on immune parameters in rat gastrointestinal and systemic tissues under homeostatic immune conditions was examined. Only the diet containing WB altered T and B cell populations in mesenteric lymph nodes (MLN) and spleen. Analysis of tissue cytokine profiles showed ileal cytokine-induced neutrophil chemoattractant (CINC)-1, interleukin 4 (IL-4), IL-10 and transforming growth factor (TGF)-β1 levels increased in rats fed WB, whereas CINC-1, IL-6, and TGF-β1 levels were highest in the colon of OB-fed rats. In the liver, levels of TGF-β1 increased in rats fed diets containing RS or OB. Sex-based differences in immune parameters were observed in rats fed WB. It is apparent that different dietary fermentable substrates have distinct effects on immune activity under homeostatic conditions. These findings provide new insight into immunological outcomes associated with fibres and starches as dietary supplements.