Immune-Modulatory Effects and Potential Working Mechanisms of Orally Applied Nondigestible Carbohydrates

Abstract

Orally applied nondigestible carbohydrates (NDC) have been associated with immune-modulating effects and other health benefits. The effects of prebiotic carbohydrates have recently received much attention, but other NDC have been reported to induce immune modulation as well. Many different effects have been shown on parameters of innate and specific immunity, mostly in animal experiments or in vitro. Data from clinical trials are limited, but promising studies have reported beneficial effects on mucosal and systemic immunity in humans. NDC are fermented to various degrees by the intestinal microbiota. Therefore, immune-modulatory properties have often been attributed to microbiota-dependent effects, especially in the case of prebiotic NDC. However, some NDC have been reported to bind to specific receptors on cells of the immune system, suggesting microbiota-independent, immune-modulatory effects play a role as well. This review aims to provide an overview of the published immune-modulatory effects in vitro and in vivo induced by NDC such as fructans, galactooligosaccharides, beta-glucans, pectins, and resistant starch. In addition, issues related to the underlying mechanisms are discussed: interaction between bacteria, their metabolites and the immune system, as well as direct effects of NDC via lectin receptors.

The bifidogenic effect of inulin and oligofructose and its consequences for gut health

“…This may be related to a fermentation product of inulin, as it has been reported that butyrate suppresses lymphocyte proliferation, reduces cytokine expression and enhances IL-10 production in rats. However, as Peyer's patches are located in the small intestine, whereas fructans are fermented mainly in the large intestine, it could be speculated that microbiota-independent mechanisms may also have a role in the observed effects (Vos et al, 2007).…”

Beneficial immune modulatory effects of a specific nutritional combination in a murine model for cancer cachexia

“…The optimal dose, formulation, relative contributions of EPA and DHA in fish oil and the target population remain yet to be defined (Fearon et al, 2006;Sijben and Calder, 2007). The use of non-digestible carbohydrates, especially of prebiotic oligosaccharides, is based on the immunemodulating activities observed in several animal experiments and clinical trials (Vos et al, 2007). In an influenza vaccination model in healthy C57BL/6 mice, a specific mixture of oligosaccharides stimulated the vaccine-specific delayed-type hypersensitivity response as a marker for T-helper 1 (Th1) immunity (Vos et al, 2006).…”

A dietary dairy/yeast prebiotic and flaxseed oil enhance growth, hematological and immunological parameters in channel catfish at a suboptimal temperature (15°C)

“…Prebiotics are nondigestible dietary compounds that can be metabolized by specific microflora in the gut (Gibson and Roberfroid, 1995). Typical benefits include improved nutrient assimilation, growth and immune function (Vos et al, 2007). A dairy/yeast prebiotic had beneficial effects in golden shiners Notemigonus crysoleucas and goldfish Carassius auratus in our laboratory (Lochmann et al, 2009;Lochmann et al, 2011), but the same dairy/yeast prebiotic did not enhance growth or feed conversion of channel catfish at optimal temperatures (27°C to 28°C) (Thompson, 2009).…”