ABSTRACT: Inflammatory Bowel Disease (IBD) is a term describing a collection of conditions characterised by chronic inflammatory disorder of the gastrointestinal tract involving an inappropriate immune response to commensal microorganisms in a genetically susceptible host. Four kiwifruit extracts, aqueous and ethyl acetate extracts of gold kiwifruit (Actinidia chinensis) or green kiwifruit (A. deliciosa), have previously demonstrated anti-inflammatory activity using in vitro models of IBD. This study examined whether these kiwifruit extracts had immune modulating effects in vivo against inflammatory processes known to be increased in patients with IBD. KFEs were used as a dietary intervention in Il10-/- mice (an in vivo model of IBD) and the C57BL/6J background strain in a 3 x 2 factorial design. While all Il10-/- mice developed significant colonic inflammation compared to the C57BL/6J mice, this was not affected by the inclusion of KFE in the diet. Whole genome gene and protein expression level profiling indicated that KFEs influenced immune signalling pathways and metabolic processes within the colonic tissue; however, the effects were subtle. In particular, adaptive immune pathways were reduced by three out of four kiwifruit extracts, with greater reduction seen in the C57BL/6J mice. This suggests that while immune-modulating activity was present in vivo, KFEs did not reduce inflammatory processes relevant to IBD. Experimental design. Two experiments were conducted, one using extracts from gold kiwifruit and one using extracts from green kiwifruit. Within each experiment, both Il10-/- and C57 mice were randomly divided into three diet treatment groups, to ive the following 12 treatments: 1) Gold Kiwifruit Experiment, C57BL/6J mice, Control diet (AIN-76A), 2) Gold Kiwifruit Experiment, C57BL/6J mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 3) Gold Kiwifruit Experiment, C57BL/6J mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) 4) Gold Kiwifruit Experiment, Il10-/- mice, Control diet (AIN-76A), 5) Gold Kiwifruit Experiment, Il10-/- mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 6) Gold Kiwifruit Experiment, Il10-/- mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) 7) Green Kiwifruit Experiment, C57BL/6J mice, Control diet (AIN-76A), 8) Green Kiwifruit Experiment, C57BL/6J mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 9) Green Kiwifruit Experiment, C57BL/6J mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) 10) Green Kiwifruit Experiment, Il10-/- mice, Control diet (AIN-76A), 11) Green Kiwifruit Experiment, Il10-/- mice, Aqueous Kiwifruit Extract Supplemented Diet (AIN-76A + 5% Aqueous KFE) 12) Green Kiwifruit Experiment, Il10-/- mice, Ethyl Acetate Kiwifruit Extract Supplemented Diet (AIN-76A + 0.11% Ethyl Acetate KFE) Six biological replicates were analysed from each treatment group, except for groups 3 and 7 where five replicates were analysed due to array quality issues with the sixth replicate. Each replicate contained mRNA from one mouse. A reference design was used, where each slide was hybridised with mRNA from one sample (green channel) and mRNA from a common reference pool (red channel).
