66, 1.69 and 1.48 in comparison to animals fed the control diet on days 2, 5 and 9 post infection, respectively (p < 0.05). Animals fed the 20% rice bran diet showed a reduction in Salmonella fecal shedding by a log10 value check details of
2.13, 1.69, 2.04 and 1.73 in comparison to the animals fed the control diet on days 2, 5, 7 and 9, respectively. No significant difference was observed in Salmonella fecal shedding between the 10 and 20% rice bran diet groups. These data demonstrate that pre-feeding dietary rice bran for one week reduced the susceptibility of mice to oral infection with the Salmonella pathogen as measured by fecal shedding. Figure 1 Effect of dietary rice bran on Salmonella fecal shedding of mice. Fecal shedding was examined in Salmonella infected animals fed control, 10% and 20% rice bran diet for 3 weeks (one week prior and 2 weeks post challenge). Data are shown as mean ± standard deviation of mean
log10 CFU per gram of feces (n = 5 mice/diet group), and data are representative of three independently conducted experiments. Repeated measures ANOVA and post hoc Tukey’s test were applied. Significance is shown by * (P < 0.05) and ** (P < 0.01). Effect of dietary rice bran on serum cytokines Previous research demonstrated that in response to primary Salmonella infection, the host immune system releases massive amounts of the cytokines MG-132 purchase such as TNF-α, IFN-γ and IL-12 locally and systemically [24]. The local inflammatory response has been shown to shift the microbiota composition allowing Salmonella the opportunity to efficiently colonize in the gut [25]. Therefore, due to the fact that rice bran mediated a decrease in fecal shedding, we next measured the cytokine level
in the serum of mice consuming either the 10 or 20% rice bran diets (Figure 2). Mice fed the 10% rice bran diet for 7 days had decreased serum levels of TNF-α, IFN-γ, and IL-12 by 60.4, 136.3 and 27.6 pg/ml respectively in comparison Nintedanib (BIBF 1120) to animals on the control diet (p < 0.05). Additionally, mice fed the 20% rice bran diet showed decreased levels of serum IFN-γ in comparison to control animals (p < 0.05). These data suggests that rice bran induced suppression of systemic cytokine production may play a role in reducing the colonization of Salmonella. Figure 2 Effect of dietary rice bran on serum TNF- α, IFN-γ and IL-12 levels in Salmonella infected mice. Blood was drawn at days 0, 7 and 14 following Salmonella infection and serum was analyzed for TNF- α (A), IFN-γ (B) and IL-12 (C) levels in control, 10% and 20% rice bran diet groups. Data are shown as mean ± standard deviation of mean (n = 3 mice/diet group). Significance was measured by two-way ANOVA and Bonferroni post hoc test. Effect of dietary rice bran on fecal Lactobacillus spp Members of the genus Lactobacillus are potent commensal bacteria with potential for eradication of Salmonella infection [26].