Mechanisms of Action of Prebiotics and Their Effects on Gastro-Intestinal Disorders in Adults

Abstract

In recent years, research has focused on the use of dietary fibers and prebiotics, since many of these polysaccharides can be metabolized by intestinal microbiota, leading to the production of short-chain fatty acids. The metabolites of prebiotic fermentation also show anti-inflammatory and immunomodulatory capabilities, suggesting an interesting role in the treatment of several pathological conditions. Galacto-oligosaccharide and short-and long-chain fructans (Fructo-oligosaccharides and inulin) are the most studied prebiotics, even if other dietary compounds seem to show the same features. There is an increasing interest in dietary strategies to modulate microbiota. The aim of this review is to explore the mechanisms of action of prebiotics and their effects on the principal gastro-intestinal disorders in adults, with a special focus on Galacto-oligosaccharides, Fructo-oligosaccharides, lactulose and new emerging substances which currently have evidence of prebiotics effects, such as xilooligosaccharides, soybean oligosaccharides, isomaltooligosaccharides, lactobionic acid, resistant starch and polyphenols.

The Effectiveness of Synbiotic Preparation Containing Lactobacillus and Bifidobacterium Probiotic Strains and Short Chain Fructooligosaccharides in Patients with Diarrhea Predominant Irritable Bowel Syndrome—A Randomized Double-Blind, Placebo-Controlled Study

“…The mechanism of probiotic efficacy is supposed to be connected with the impact on the gut microbiota and its metabolome and with a direct activation of the gut associated lymphoid tissue as well as a modification of the microbiome-gut-brain axis. However, prebiotic oligosaccharides also play an important role in modulation of the intestinal microbiota and are the main source of short chain fatty acids such as acetate, propionate and butyrate [ 34 ]. Recent analyses of the gut microbiota of IBS patients have shown that microbial dysbiosis in IBS depends on IBS subtypes, and IBS-D but not IBS-C is characterized by a reduction of butyrate producing bacteria such as Ruminococcaeae , unknown Clostridiales and Erisipelotrichaceae [ 14 ].…”

The Pros and Cons of Using Algal Polysaccharides as Prebiotics

“…Finally, prebiotic-derived SCFAs also stimulate the immune system and exert anti-inflammatory activities by inhibiting NFKB pathway, reinforcing the defense of the individuals and reducing the development of allergic and inflammatory diseases ( 36 ). The mechanisms of action of prebiotics at molecular and cellular level were the subject of several recent reviews ( 37 , 38 ). However, it is important to state that soluble dietary fiber can also exert physiological effects through mechanisms independent of their prebiotic effects.…”

Effect of Unripe Banana Flour on Gut-Derived Uremic Toxins in Individuals Undergoing Peritoneal Dialysis: A Randomized, Double-Blind, Placebo-Controlled, Crossover Trial

“…In healthy individuals, it was observed that the bifidogenic effect of prebiotics is dose-dependent and the minimum dose required may vary depending on the type of prebiotic. While for FOS it seems the minimum dose is 10 g/day, for inulin, a lower dose seems to be enough (2.5–5 g/day) [ 61 ]. As far as we know, there is no study in CKD that evaluated the dose–response effect of prebiotics on the serum level of uremic toxins.…”