Consumption of Rice Bran Increases Mucosal Immunoglobulin A Concentrations and Numbers of IntestinalLactobacillusspp.

Abstract

Gut-associated lymphoid tissue maintains mucosal homeostasis by combating pathogens and inducing a state of hyporesponsiveness to food antigens and commensal bacteria. Dietary modulation of the intestinal immune environment represents a novel approach for enhancing protective responses against pathogens and inflammatory diseases. Dietary rice bran consists of bioactive components with disease-fighting properties. Therefore, we conducted a study to determine the effects of whole dietary rice bran intake on mucosal immune responses and beneficial gut microbes. Mice were fed a 10% rice bran diet for 28 days. Serum and fecal samples were collected throughout the study to assess total immunoglobulin A (IgA) concentrations. Tissue samples were collected for cellular immune phenotype analysis, and concentrations of native gut Lactobacillus spp. were enumerated in the fecal samples. We found that dietary rice bran induced an increase in total IgA locally and systemically. In addition, B lymphocytes in the Peyer's patches of mice fed rice bran displayed increased surface IgA expression compared with lymphocytes from control mice. Antigen-presenting cells were also influenced by rice bran, with a significant increase in myeloid dendritic cells residing in the lamina propria and mesenteric lymph nodes. Increased colonization of native Lactobacillus was observed in rice bran-fed mice compared with control mice. These findings suggest that rice bran-induced microbial changes may contribute to enhanced mucosal IgA responses, and we conclude that increased rice bran consumption represents a promising dietary intervention to modulate mucosal immunity for protection against enteric infections and induction of beneficial gut bacteria.

Dietary Rice Bran Protects against Rotavirus Diarrhea and Promotes Th1-Type Immune Responses to Human Rotavirus Vaccine in Gnotobiotic Pigs

“…Importantly, ␥-oryzanol significantly promoted the development of antibody responses in rats stimulated with sheep red blood cells (4). Total local (feces) and systemic (serum) IgA levels and IgA expression of Peyer's patches B cells were also enhanced in mice fed a 10% RB diet, suggesting that RB promoted both mucosal and systemic B cell development (2). These studies demonstrated the immunostimulatory effects of RB on multiple components of the immune system.…”

“…It has been studied for bioactive functions such as the prevention and treatment of chronic diseases, growth of beneficial intestinal microbes, induction of mucosal and systemic immune responses, and protection against enteric pathogens (2)(3)(4)(5). Thus, this agricultural by-product represents a promising and practical diet-based solution for increasing the innate resistance against enteric pathogens that cause diarrhea.…”

“…Given that RB can support colonization of gut probiotics (e.g., Lactobacillus spp. ), enhance mucosal IgA production (2), and significantly reduce the enteric burden of Salmonella infection in mice (5), continued investigation of the mechanisms of dietary RB in its protection against viral pathogens that cause significant global morbidity and mortality (e.g., rotavirus) is warranted.…”

Rice co-products in pig feed during the starter phase (15 to 30 kg)

“…Rice and corn co-products have shown similar effects on animal performance, but rice may induce a prebiotic effect and increased serum concentrations of IgA, indicating an improved immune response (HENDERSON et al, 2012), without effect of inclusion of defatted rice bran on concentration of peptide YY (PYY), indicating that the energy status of the pigs was not changed (CASAS; STEIN, 2016a). In addition, the tendency for decreasing concentrations of TNF-α in plasma observed in pigs fed diets with increasing concentrations of full-fat rice bran (FFRB) indicates a potential for reducing inflammatory responses in the intestine (CASAS; STEIN, 2016a).…”

Effects of Graded Levels of Rice Bran Oil on Laying Performance, Blood Parameters and Egg Yolk Cholesterol in Hy-Line Laying Hens

“…Dietary supplementation of rice bran or RBO in mice or broilers has shown to enhance improved immune response (Henderson et al, 2012;Kang and Kim, 2016). However, data pertaining to the effects of dietary supplementation of RBO on the laying performance, egg quality, and egg yolk cholesterol of laying hens are limited.…”